@misc{OPUS4-10935, title = {Pr{\"u}fungsordnung f{\"u}r den viersemestrigen Masterstudiengang „Industrial Engineering" Fachbereich Wirtschaftswissenschaften Fachbereich Maschinenbau und Mechatronik an der Fachhochschule Aachen : vom 11. Dezember 2014 - FH-Mitteilung Nr. 156/2014 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 5. Februar 2019 - FH-Mitteilung Nr. 6/2019 (Nichtamtliche lesbare Fassung | Studienbeginn ab WS 2018/19)}, organization = {FH Aachen}, pages = {10 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10936, title = {4. Ordnung zur {\"A}nderung der Zugangsordnung f{\"u}r den Masterstudiengang Elektrotechnik im Fachbereich Elektrotechnik und Informationstechnik an der Fachhochschule Aachen : vom 5. November 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10937, title = {Zugangsordnung f{\"u}r die Masterstudieng{\"a}nge „Elektrotechnik" und „Elektrotechnik (Teilzeit)" im Fachbereich Elektrotechnik und Informationstechnik an der Fachhochschule Aachen : vom 22. Januar 2010 - FH-Mitteilung Nr. 6/2010 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 5. November 2019 - FH-Mitteilung Nr. 109/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10938, title = {Pr{\"u}fungsordnung f{\"u}r die Masterstudieng{\"a}nge „Elektrotechnik" und „Elektrotechnik (Teilzeit)" im Fachbereich Elektrotechnik und Informationstechnik an der Fachhochschule Aachen : vom 5. November 2019}, organization = {FH Aachen}, pages = {9 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10939, title = {4. Ordnung zur {\"A}nderung der Zugangsordnung f{\"u}r den Masterstudiengang Information Systems Engineering im Fachbereich Elektrotechnik und Informationstechnik an der Fachhochschule Aachen : vom 5. November 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10940, title = {Zugangsordnung f{\"u}r die Masterstudieng{\"a}nge „Information Systems Engineering" und „Information Systems Engineering (Teilzeit)" im Fachbereich Elektrotechnik und Informationstechnik an der Fachhochschule Aachen : vom 22. Januar 2010 - FH-Mitteilung Nr. 4/2010 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 5. November 2019 - FH-Mitteilung Nr. 112/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10850, title = {Ordnung zur {\"A}nderung der Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge „Schienenfahrzeugtechnik" „Schienenfahrzeugtechnik (Teilzeit)" und „Dualer Studiengang Schienenfahrzeugtechnik (DIRail)" im Fachbereich Maschinenbau und Mechatronik an der Fachhochschule Aachen}, organization = {FH Aachen}, pages = {2}, year = {2019}, language = {de} } @misc{OPUS4-10851, title = {Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge „Schienenfahrzeugtechnik" „Schienenfahrzeugtechnik (Teilzeit)" und „Dualer Studiengang Schienenfahrzeugtechnik (DIRail)" im Fachbereich Maschinenbau und Mechatronik an der Fachhochschule Aachen}, organization = {FH Aachen}, pages = {14 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10852, title = {2. Ordnung zur {\"A}nderung der Pr{\"u}fungsordnung f{\"u}r den dualen ausbildungsintegrierenden Bachelorstudiengang „Physiotherapie" und den berufsbegleitenden Bachelorstudiengang „Physiotherapie" an der Fachhochschule Aachen in Kooperation mit der Medizinischen Fakult{\"a}t der Rheinisch-Westf{\"a}lisch Technischen Hochschule Aachen und der Physiotherapieschule des Universit{\"a}tsklinikums Aachen (UK Aachen)}, organization = {FH Aachen}, pages = {6 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10853, title = {Pr{\"u}fungsordnung f{\"u}r den dualen ausbildungsintegrierenden Bachelorstudiengang „Physiotherapie" und den berufsbegleitenden Bachelorstudiengang „Physiotherapie" an der Fachhochschule Aachen in Kooperation mit der Medizinischen Fakult{\"a}t der Rheinisch-Westf{\"a}lisch Technischen Hochschule Aachen und der Physiotherapieschule des Universit{\"a}tsklinikums Aachen (UK Aachen)}, organization = {FH Aachen}, pages = {9 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10854, title = {3. Ordnung zur {\"A}nderung der Studien- und Pr{\"u}fungsordnung f{\"u}r den Bachelorstudiengang Bauingenieurwesen (7-semestrig), Bachelorstudiengang Bauingenieurwesen mit Praxissemester (8-semestrig), Bachelorstudiengang Bauingenieurwesen mit Auslandssemester (8-semestrig), Abschluss Bachelor of Engineering}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10855, title = {Ordnung zur {\"A}nderung der Ordnung zur Aufhebung der Studien- und Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge „Bauingenieurwesen" (7-semestrig), „Bauingenieurwesen mit Praxissemester" (8-semestrig) und „Bauingenieurwesen mit Auslandssemester" (8-semestrig) vom 1. September 2011 (FH-Mitteilung Nr. 76/2011) in der Fassung der Bekanntmachung der {\"A}nderungsordnungen vom 22. August 2013 (FH- Mitteilung Nr. 88/2013) und vom 8. Juni 2016 (FH-Mitteilung Nr. 80/2016) an der Fachhochschule Aachen}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10857, title = {Ordnung zur {\"A}nderung der Ordnung zur Aufhebung der Studien- und Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge „Bauingenieurwesen" (7-semestrig), „Bauingenieurwesen mit Praxissemester" (8-semestrig) und „Bauingenieurwesen mit Auslandssemester" (8-semestrig) vom 1. September 2011 (FH-Mitteilung Nr. 76/2011) in der Fassung der Bekanntmachung der {\"A}nderungsordnungen vom 22. August 2013 (FH- Mitteilung Nr. 88/2013) und vom 8. Juni 2016 (FH-Mitteilung Nr. 80/2016) an der Fachhochschule Aachen}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10858, title = {Ordnung zur {\"A}nderung der Ordnung zur Aufhebung der Studien- und Pr{\"u}fungsordnung f{\"u}r den Bachelorstudiengang „Holzingenieurwesen" (7-semestrig) vom 16. Juli 2012 (FH-Mitteilung Nr. 66/2012) in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 6. Juli 2016 (FH-Mitteilung Nr. 95/2016) an der Fachhochschule Aachen}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10859, title = {3. Ordnung zur {\"A}nderung der Studien- und Pr{\"u}fungsordnung f{\"u}r den dualen Bachelorstudiengang Bauingenieurwesen, Netzingenieur (9 Semester) und den Bachelorstudiengang Bauingenieurwesen - Netzingenieur (7 Semester) Abschluss Bachelor of Engineering im Fachbereich Bauingenieurwesen an der Fachhochschule Aachen}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10898, title = {Studien- und Pr{\"u}fungsordnung f{\"u}r den Masterstudiengang Facility Management - Abschluss Master of Engineering - : vom 29. November 2012 - FH-Mitteilung Nr. 127/2012 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 16. August 2019 - FH-Mitteilung Nr. 82/2019 (Nichtamtliche lesbare Fassung | Studienbeginn WS 2016/17-SS 2018)}, organization = {FH Aachen}, pages = {7 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10899, title = {Ordnung zur Aufhebung der Studien- und Pr{\"u}fungsordnung f{\"u}r den Masterstudiengang „Facility Management" vom 29. November 2012 (FH-Mitteilung Nr. 127/2012) in der Fassung der Bekanntmachung der {\"A}nderungsordnungen vom 3. Februar 2016 (FH-Mitteilung Nr. 10/2016) und 16. August 2019 (FH-Mitteilung Nr. 82/2019) an der Fachhochschule Aachen : vom 24. Juli 2018 - FH-Mitteilung Nr. 122/2018 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 16. August 2019 - FH-Mitteilung Nr. 83/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10900, title = {Beitragsordnung des Studierendenwerks Aachen (21. {\"A}nderung) : vom 3. Juli 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @article{LepkeLilliePetersonetal.2006, author = {Lepke, Dietrich and Lillie, Dirk and Peterson, Leif Arne and Hempe, Thomas}, title = {Liegedauer von Holzschwellen in Tunneln der Hamburger Hochbahn AG}, series = {EI - Der Eisenbahningenieur}, journal = {EI - Der Eisenbahningenieur}, number = {2}, publisher = {DVV Media Group}, address = {Hamburg}, issn = {0013-2810}, pages = {46 -- 50}, year = {2006}, abstract = {Die Hamburger Hochbahn AG ben{\"o}tigte im Rahmen der {\"U}berarbeitung einer langfristigen Instandhaltungs- und Erneuerungsstrategie f{\"u}r ihre U-Bahn-Infrastruktur eine belastbare Aussage {\"u}ber die Restlebensdauer der Holzschwellen im Tunnel. Aus diesem Grunde beauftragte sie das Institut f{\"u}r Verkehrswesen, Eisenbahnbau und -betrieb (IVE) der Universit{\"a}t Hannover mit der Erstellung eines entsprechenden Gutachtens. Das Ergebnis f{\"u}hrte zu der gesicherten Aussage einer erheblich l{\"a}ngeren Restlebensdauer der Tunnelschwellen gegen{\"u}ber den bisherigen, gesch{\"a}tzten Annahmen.}, language = {de} } @phdthesis{Peterson2008, author = {Peterson, Leif Arne}, title = {Zum Tragverhalten nachgiebig verbundener Biegetr{\"a}ger aus Holz}, publisher = {Fraunhofer IRB Verlag}, address = {Stuttgart}, isbn = {9783816775973}, pages = {169 Seiten}, year = {2008}, abstract = {In der vorliegenden Dissertation werden zun{\"a}chst die linear elastischen Bemessungsm{\"o}glichkeiten f{\"u}r nachgiebig verbundene Biegetr{\"a}ger unter statischer und dynamischer Beanspruchung diskutiert. Zum Vergleich wurden praktische Untersuchungen an zweiteiligen Kantholzbiegetr{\"a}gem mit mechanischen Verbindungsmitteln unterschiedlicher Verformungscharakteristika durchgef{\"u}hrt, ebenso wie umfangreiche Materialpr{\"u}fungen an den zusammengef{\"u}gten Einzelquerschnitten. Hierdurch werden die Unterschiede zum realen, nicht elastischen, statischen Tragverhalten aufgezeigt. Der f{\"u}r das dynamische Verhalten maßgebende Systemparameter der Eigenfrequenz wird f{\"u}r mehrteilige Biegetr{\"a}ger theoretisch hinterfragt und an den nachgiebig verbundenen Kantholzbiegetr{\"a}gem gemessen. Begleitet von weiteren praktischen Untersuchungen an einzelnen Verbindungsmitteln unter Blockscherbeanspruchung wird die rechnerische Ber{\"u}cksichtigung des plastischen Verbindungsmittelverhaltens auf zwei theoretischen Wegen erforscht. Auf Grundlage der Untersuchungen wird ein neues, semianalytisches y-Verfahren entwickelt. Gegen{\"u}ber den Berechnungen mit finiten Volumen- und Kontakt-Elementen erweist sich das neue Verfahren auf Basis der, um die schubweichen Fugen erweiterten, Balkentheorie als leistungsf{\"a}higer. Der Einfluss des plastischen Verbindungsmittelverhaltens wird durch vergleichende Parameterstudien mit diesem neuen Verfahren als vom anerkannten Stand der Technik ausreichend ber{\"u}cksichtigt identifiziert. F{\"u}r die linear elastische Dimensionierung werden optimierte Verbindungsmittelanordnungen hergeleitet, die durch {\"u}bersichtliche Erg{\"a}nzungen zum existierenden Bemessungskonzept des y-Verfahrens eine exaktere Berechnung erm{\"o}glichen.}, language = {de} } @article{NabilPetersonSchmidtetal.2010, author = {Nabil, F. and Peterson, Leif Arne and Schmidt, A. and Geerdes, D.}, title = {Die Holzkuppel des Neuen Palais in Potsdam}, series = {Bauingenieur}, volume = {85}, journal = {Bauingenieur}, number = {8}, publisher = {Springer-VDI-Verlag}, address = {D{\"u}sseldorf}, issn = {0005-6650}, pages = {324 -- 330}, year = {2010}, language = {de} } @book{NebgenPeterson2015, author = {Nebgen, Nikolaus and Peterson, Leif Arne}, title = {Holzbau kompakt nach Eurocode 5}, edition = {5. Auflage}, publisher = {Beuth}, address = {Berlin}, isbn = {978-3-410-25455-3}, pages = {XII, 267 Seiten}, year = {2015}, abstract = {"Holzbau kompakt" wurde sowohl f{\"u}r Studierende als auch Praktiker konzipiert und beschr{\"a}nkt sich nicht auf reine Holzbauaufgaben, sondern setzt sich ggf. auch mit der Tragwerkslehre auseinander. Die Neuauflage basiert auf dem Eurocode 5 und ber{\"u}cksichtigt zahlreiche neue Erkenntnisse aus Forschung und praxisnaher Entwicklung. Neben den Grundlagen der Bemessung, der Baustoffe, der Dauerhaftigkeit und des Brandschutzes konzentriert sich das Grundlagenwerk besonders auf das Konstruieren mit Holz und Holzwerkstoffen, anschaulich dargestellt an sehr ausf{\"u}hrlichen Beispielen f{\"u}r Wohnhaus und Hallentragwerk.}, language = {de} } @book{HolschemacherPetersPetersonetal.2013, author = {Holschemacher, Klaus and Peters, Klaus and Peterson, Leif Arne and Schneider, Klaus-J{\"u}rgen and Thiele, Ralf}, title = {Konstruktiver Ingenieurbau kompakt: Formelsammlung und Bemessungshilfen nach Eurocode f{\"u}r die Bereiche: Lastannahmen, Holzbau, Mauerwerksbau, Stahlbau, Stahlbetonbau, Geotechnik, statische Hinweise}, edition = {4., vollst{\"a}ndig {\"u}berarbeitete Auflage}, publisher = {Beuth}, address = {Berlin}, isbn = {978-3-410-22775-5}, pages = {384 Seiten}, year = {2013}, abstract = {Das kompakte Nachschlagewerk f{\"u}r den konstruktiven Ingenieurbau wurde f{\"u}r den t{\"a}glichen Gebrauch auf der Baustelle konzipiert und stellt alle f{\"u}r die rechnerische Nachweisf{\"u}hrung und Konstruktion von Bauteilen wichtigsten Angaben in Form einer Formelsammlung mit Nachweishilfen zur Verf{\"u}gung. Der Inhalt wurde auf Basis der neuen Eurocodes komplett aktualisiert und erweitert. Die 4. Auflage enth{\"a}lt in bew{\"a}hrter Manier eine umfangreiche Formelsammlung, Querschnittswerte und Bemessungshilfen zu den Bereichen Lastannahmen, Holzbau, Mauerwerksbau, Stahlbau, Stahlbetonbau, Geotechnik sowie statische Hinweise. Farbiges Papier erleichtert den zielgerichteten Zugriff auf die einzelnen Fachgebiete.}, language = {de} } @incollection{FruehwaldPetersonHasenstab2012, author = {Fr{\"u}hwald, Katja and Peterson, Leif Arne and Hasenstab, Andreas}, title = {Pr{\"u}fverfahren zur Begutachtung der Materialeigenschaften von Holztragwerken}, series = {Bauphysik-Kalender 2012: Schwerpunkt: Geb{\"a}udediagnostik}, booktitle = {Bauphysik-Kalender 2012: Schwerpunkt: Geb{\"a}udediagnostik}, editor = {Fouad, Nabil A.}, publisher = {Ernst \& Sohn}, address = {Berlin}, isbn = {9783433029862 (Print)}, doi = {10.1002/9783433601235.ch4}, pages = {103 -- 155}, year = {2012}, abstract = {Dieses Kapitel beinhaltet: - Einleitung - Ausgew{\"a}hlte typische Sch{\"a}den an Holzbauwerken - Das Material Holz und seine Besonderheiten - Bestandserfassung - Labormethoden - Begutachtungsbeispiele - Zusammenfassung und Schlussfolgerungen - Literatur}, language = {de} } @article{OezsoyluAliaziziWagneretal.2024, author = {{\"O}zsoylu, Dua and Aliazizi, Fereshteh and Wagner, Patrick and Sch{\"o}ning, Michael Josef}, title = {Template bacteria-free fabrication of surface imprinted polymer-based biosensor for E. coli detection using photolithographic mimics: Hacking bacterial adhesion}, series = {Biosensors and Bioelectronics}, volume = {261}, journal = {Biosensors and Bioelectronics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1873-4235 (eISSN)}, doi = {10.1016/j.bios.2024.116491}, pages = {11 Seiten}, year = {2024}, abstract = {As one class of molecular imprinted polymers (MIPs), surface imprinted polymer (SIP)-based biosensors show great potential in direct whole-bacteria detection. Micro-contact imprinting, that involves stamping the template bacteria immobilized on a substrate into a pre-polymerized polymer matrix, is the most straightforward and prominent method to obtain SIP-based biosensors. However, the major drawbacks of the method arise from the requirement for fresh template bacteria and often non-reproducible bacteria distribution on the stamp substrate. Herein, we developed a positive master stamp containing photolithographic mimics of the template bacteria (E. coli) enabling reproducible fabrication of biomimetic SIP-based biosensors without the need for the "real" bacteria cells. By using atomic force and scanning electron microscopy imaging techniques, respectively, the E. coli-capturing ability of the SIP samples was tested, and compared with non-imprinted polymer (NIP)-based samples and control SIP samples, in which the cavity geometry does not match with E. coli cells. It was revealed that the presence of the biomimetic E. coli imprints with a specifically designed geometry increases the sensor E. coli-capturing ability by an "imprinting factor" of about 3. These findings show the importance of geometry-guided physical recognition in bacterial detection using SIP-based biosensors. In addition, this imprinting strategy was employed to interdigitated electrodes and QCM (quartz crystal microbalance) chips. E. coli detection performance of the sensors was demonstrated with electrochemical impedance spectroscopy (EIS) and QCM measurements with dissipation monitoring technique (QCM-D).}, language = {en} } @article{KetelhutBrueggeGoelletal.2020, author = {Ketelhut, Maike and Br{\"u}gge, G. M. and G{\"o}ll, Fabian and Braunstein, Bjoern and Albracht, Kirsten and Abel, Dirk}, title = {Adaptive iterative learning control of an industrial robot during neuromuscular training}, series = {IFAC PapersOnLine}, volume = {53}, journal = {IFAC PapersOnLine}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2020.12.741}, pages = {16468 -- 16475}, year = {2020}, abstract = {To prevent the reduction of muscle mass and loss of strength coming along with the human aging process, regular training with e.g. a leg press is suitable. However, the risk of training-induced injuries requires the continuous monitoring and controlling of the forces applied to the musculoskeletal system as well as the velocity along the motion trajectory and the range of motion. In this paper, an adaptive norm-optimal iterative learning control algorithm to minimize the knee joint loadings during the leg extension training with an industrial robot is proposed. The response of the algorithm is tested in simulation for patients with varus, normal and valgus alignment of the knee and compared to the results of a higher-order iterative learning control algorithm, a robust iterative learning control and a recently proposed conventional norm-optimal iterative learning control algorithm. Although significant improvements in performance are made compared to the conventional norm-optimal iterative learning control algorithm with a small learning factor, for the developed approach as well as the robust iterative learning control algorithm small steady state errors occur.}, language = {en} } @article{KetelhutKolditzGoelletal.2019, author = {Ketelhut, Maike and Kolditz, Melanie and G{\"o}ll, Fabian and Braunstein, Bjoern and Albracht, Kirsten and Abel, Dirk}, title = {Admittance control of an industrial robot during resistance training}, series = {IFAC-PapersOnLine}, volume = {52}, journal = {IFAC-PapersOnLine}, number = {19}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2405-8963}, doi = {10.1016/j.ifacol.2019.12.102}, pages = {223 -- 228}, year = {2019}, abstract = {Neuromuscular strength training of the leg extensor muscles plays an important role in the rehabilitation and prevention of age and wealth related diseases. In this paper, we focus on the design and implementation of a Cartesian admittance control scheme for isotonic training, i.e. leg extension and flexion against a predefined weight. For preliminary testing and validation of the designed algorithm an experimental research and development platform consisting of an industrial robot and a force plate mounted at its end-effector has been used. Linear, diagonal and arbitrary two-dimensional motion trajectories with different weights for the leg extension and flexion part are applied. The proposed algorithm is easily adaptable to trajectories consisting of arbitrary six-dimensional poses and allows the implementation of individualized trajectories.}, language = {en} } @inproceedings{KetelhutGoellBraunsteinetal.2019, author = {Ketelhut, Maike and G{\"o}ll, Fabian and Braunstein, Bjoern and Albracht, Kirsten and Abel, Dirk}, title = {Iterative learning control of an industrial robot for neuromuscular training}, series = {2019 IEEE Conference on Control Technology and Applications}, booktitle = {2019 IEEE Conference on Control Technology and Applications}, publisher = {IEEE}, address = {New York}, isbn = {978-1-7281-2767-5 (ePub)}, doi = {10.1109/CCTA.2019.8920659}, pages = {7 Seiten}, year = {2019}, abstract = {Effective training requires high muscle forces potentially leading to training-induced injuries. Thus, continuous monitoring and controlling of the loadings applied to the musculoskeletal system along the motion trajectory is required. In this paper, a norm-optimal iterative learning control algorithm for the robot-assisted training is developed. The algorithm aims at minimizing the external knee joint moment, which is commonly used to quantify the loading of the medial compartment. To estimate the external knee joint moment, a musculoskeletal lower extremity model is implemented in OpenSim and coupled with a model of an industrial robot and a force plate mounted at its end-effector. The algorithm is tested in simulation for patients with varus, normal and valgus alignment of the knee. The results show that the algorithm is able to minimize the external knee joint moment in all three cases and converges after less than seven iterations.}, language = {en} } @misc{BlottnerHastermannMuckeltetal.2019, author = {Blottner, Dieter and Hastermann, Maria and Muckelt, Paul and Albracht, Kirsten and Schoenrock, Britt and Salanova, Michele and Warner, Martin and Gunga, Hans-Christian and Stokes, Maria}, title = {MYOTONES - Inflight muscle health status monitoring during long-duration space missions onboard the International Space Station: a single case study}, series = {IAC Papers Archive}, journal = {IAC Papers Archive}, publisher = {Pergamon}, address = {Oxford}, issn = {00741795}, pages = {2 Seiten}, year = {2019}, abstract = {The MYOTONES experiment is the first to monitor changes in the basic biomechanical properties (tone, elasticity and stiffness) of the resting human myofascial system due to microgravity with a oninvasive, portable device on board the ISS. The MyotonPRO device applies several brief mechanical stimuli to the surface of the skin, and the natural oscillation signals of the tissue beneath are detected and computed by the MyotonPRO. Thus, an objective, quick and easy determination of the state of the underlying tissue is possible. Two preflight, four inflight and four post flight measurements were performed on a male astronaut using the same 10 measurement points (MP) for each session. MPs were located on the plantar fascia, Achilles tendon, M. soleus, M. gastrocnemius, M. multifidus, M. splenius capitis, M. deltoideus anterior, M. rectus femoris, infrapatellar tendon, M. tibialis anterior. Subcutaneous tissues thickness above the MPs was measured using ultrasound imaging. Magnetic resonance images (MRI) of lower limb muscles and functional tests were also performed pre- and postflight. Our first measurements on board the ISS confirmed increased tone and stiffness of the lumbar multifidus muscle, an important trunk stabilizer, dysfunction of which is known to be associated with back pain. Furthermore, reduced tone and stiffness of Achilles tendon and plantar fascia were observed inflight vs. preflight, confirming previous findings from terrestrial analog studies and parabolic flights. Unexpectedly, the deltoid showed negative inflight changes in tone and stiffness, and increased elasticity, suggesting a potential risk of muscle atrophy in longer spaceflight that should be addressed by adequate inflight countermeasure protocols. Most values from limb and back MPS showed deflected patterns (in either directions) from inflight shortly after the re-entry phase on the landing day and one week later. Most parameter values then normalized to baseline after 3 weeks likely due to 1G re-adaptation and possible outcome of the reconditioning protocol. No major changes in subcutaneous tissues thickness above the MPs were found inflight vs preflight, suggesting no bias (i.e., fluid shift, extreme tissue thickening or loss). Pre- and postflight MRI and functional tests showed negligible changes in calf muscle size, power and force, which is likely due to training effects from current inflight exercise protocols. The MYOTONES experiment is currently ongoing to collect data from further crew members. The potential impact of this research is to better understand the effects of microgravity and countermeasures over the time course of an ISS mission cycle. This will enable exercise countermeasures to be tailored}, language = {en} } @article{BruksleChwallekKrastina2023, author = {Bruksle, Ieva and Chwallek, Constanze and Krastina, Anzelika}, title = {Strengthening sustainability in entrepreneurship education - implications for shifting entrepreneurial thinking towards sustainability at universities}, series = {ACTA PROSPERITATIS}, volume = {14}, journal = {ACTA PROSPERITATIS}, number = {1}, publisher = {Sciendo}, issn = {1691-6077}, doi = {10.37804/1691-6077-2023-14-37-48}, pages = {37 -- 48}, year = {2023}, abstract = {By developing innovative solutions to social and environmental problems, sustainable ventures carry greatpotential. Entrepreneurship which focuses especially on new venture creation can be developed through education anduniversities, in particular, are called upon to provide an impetus for social change. But social innovations are associatedwith certain hurdles, which are related to the multi-dimensionality, i.e. the tension between creating social,environmental and economic value and dealing with a multiplicity of stakeholders. The already complex field ofentrepreneurship education has to face these challenges. This paper, therefore, aims to identify starting points for theintegration of sustainability into entrepreneurship education. To pursue this goal experiences from three differentproject initiatives between the partner universities: Lapland University of Applied Sciences, FH Aachen University ofApplied Sciences and Turiba University are reflected and findings are systematically condensed into recommendationsfor education on sustainable entrepreneurship.}, language = {en} } @article{WerkhausenCroninAlbrachtetal.2019, author = {Werkhausen, Amelie and Cronin, Neil J. and Albracht, Kirsten and Paulsen, G{\o}ran and Larsen, Askild V. and Bojsen-M{\o}ller, Jens and Seynnes, Olivier R.}, title = {Training-induced increase in Achilles tendon stiffness affects tendon strain pattern during running}, series = {PeerJ}, journal = {PeerJ}, publisher = {Peer}, address = {London}, issn = {21678359}, doi = {10.7717/peerj.6764}, pages = {18 Seiten}, year = {2019}, abstract = {Background During the stance phase of running, the elasticity of the Achilles tendon enables the utilisation of elastic energy and allows beneficial contractile conditions for the triceps surae muscles. However, the effect of changes in tendon mechanical properties induced by chronic loading is still poorly understood. We tested the hypothesis that a training-induced increase in Achilles tendon stiffness would result in reduced tendon strain during the stance phase of running, which would reduce fascicle strains in the triceps surae muscles, particularly in the mono-articular soleus. Methods Eleven subjects were assigned to a training group performing isometric singleleg plantarflexion contractions three times per week for ten weeks, and another ten subjects formed a control group. Before and after the training period, Achilles tendon stiffness was estimated, and muscle-tendon mechanics were assessed during running at preferred speed using ultrasonography, kinematics and kinetics. Results Achilles tendon stiffness increased by 18\% (P <0:01) in the training group, but the associated reduction in strain seen during isometric contractions was not statistically significant. Tendon elongation during the stance phase of running was similar after training, but tendon recoil was reduced by 30\% (P <0:01), while estimated tendon force remained unchanged. Neither gastrocnemius medialis nor soleus fascicle shortening during stance was affected by training. Discussion These results show that a training-induced increase in Achilles tendon stiffness altered tendon behaviour during running. Despite training-induced changes in tendon mechanical properties and recoil behaviour, the data suggest that fascicle shortening patterns were preserved for the running speed that we examined. The asymmetrical changes in tendon strain patterns supports the notion that simple inseries models do not fully explain the mechanical output of the muscle-tendon unit during a complex task like running.}, language = {en} } @article{KetelhutGoellBraunsteinetal.2018, author = {Ketelhut, Maike and G{\"o}ll, Fabian and Braunstein, Bj{\"o}rn and Albracht, Kirsten and Abel, Dirk}, title = {Comparison of different training algorithms for the leg extension training with an industrial robot}, series = {Current Directions in Biomedical Engineering}, volume = {4}, journal = {Current Directions in Biomedical Engineering}, number = {1}, publisher = {De Gruyter}, address = {Berlin}, issn = {2364-5504}, doi = {10.1515/cdbme-2018-0005}, pages = {17 -- 20}, year = {2018}, abstract = {In the past, different training scenarios have been developed and implemented on robotic research platforms, but no systematic analysis and comparison have been done so far. This paper deals with the comparison of an isokinematic (motion with constant velocity) and an isotonic (motion against constant weight) training algorithm. Both algorithms are designed for a robotic research platform consisting of a 3D force plate and a high payload industrial robot, which allows leg extension training with arbitrary six-dimensional motion trajectories. In the isokinematic as well as the isotonic training algorithm, individual paths are defined i n C artesian s pace by sufficient s upport p oses. I n t he i sotonic t raining s cenario, the trajectory is adapted to the measured force as the robot should only move along the trajectory as long as the force applied by the user exceeds a minimum threshold. In the isotonic training scenario however, the robot's acceleration is a function of the force applied by the user. To validate these findings, a simulative experiment with a simple linear trajectory is performed. For this purpose, the same force path is applied in both training scenarios. The results illustrate that the algorithms differ in the force dependent trajectory adaption.}, language = {en} } @misc{OPUS4-10941, title = {Pr{\"u}fungsordnung f{\"u}r die Masterstudieng{\"a}nge „Information Systems Engineering" und „Information Systems Engineering (Teilzeit)" an der Fachhochschule Aachen : vom 5. November 2019}, organization = {FH Aachen}, pages = {9 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10942, title = {2. Ordnung zur {\"A}nderung der Beitragsordnung der Studierendenschaft der Fachhochschule Aachen : vom 7. November 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10943, title = {Beitragsordnung der Studierendenschaft der Fachhochschule Aachen : vom 11. Dezember 2018 - FH-Mitteilung Nr. 168/2018 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 7. November 2019 - FH-Mitteilung Nr. 115/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10944, title = {Gesamtpr{\"u}fungsordnung f{\"u}r den Bachelorstudiengang „Bauingenieurwesen mit Orientierungssemester" an der Fachhochschule Aachen und der RWTH Aachen : vom 8. November 2019}, organization = {FH Aachen}, pages = {6 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10945, title = {Ordnung zur {\"A}nderung der Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge Bauingenieurwesen, Bauingenieurwesen mit Praxissemester, Bauingenieurwesen mit Auslandssemester, Bauingenieurwesen Double Degree (NUST) und Bauingenieurwesen Dual an der Fachhochschule Aachen : vom 8. November 2019}, organization = {FH Aachen}, pages = {6 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10946, title = {Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge Bauingenieurwesen, Bauingenieurwesen mit Praxissemester, Bauingenieurwesen mit Auslandssemester, Bauingenieurwesen Double Degree (NUST), Bauingenieurwesen Dual und Bauingenieurwesen mit Orientierungssemester im Fachbereich Bauingenieurwesen an der Fachhochschule Aachen : vom 28. Juni 2018 - FH-Mitteilung Nr. 89/2018 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 8. November 2019 - FH-Mitteilung Nr. 118/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {20 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10947, title = {Ordnung zur {\"A}nderung der Pr{\"u}fungsordnung f{\"u}r den Bachelorstudiengang Holzingenieurwesen im Fachbereich Bauingenieurwesen an der Fachhochschule Aachen : vom 8. November 2019}, organization = {FH Aachen}, pages = {8 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10948, title = {Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge Holzingenieurwesen, Holzingenieurwesen mit Praxissemester, Holzingenieurwesen mit Auslandssemester, Holzingenieurwesen Dual und Holzingenieurwesen mit Orientierungssemester : vom 28. Juni 2018 - FH-Mitteilung Nr. 90/2018 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 8. November 2019 - FH-Mitteilung Nr. 120/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {15 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10949, title = {Zugangsordnung f{\"u}r die Masterstudieng{\"a}nge „Energiewirtschaft \& Informatik" (3 Semester) und „Energiewirtschaft \& Informatik" (4 Semester) Fachbereich Energietechnik Fachbereich Medizintechnik und Technomathematik an der Fachhochschule Aachen : vom 8. November 2019}, organization = {FH Aachen}, pages = {4 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10950, title = {Pr{\"u}fungsordnung f{\"u}r die Masterstudieng{\"a}nge „Energiewirtschaft \& Informatik" (3 Semester) und „Energiewirtschaft \& Informatik" (4 Semester) Fachbereich Energietechnik Fachbereich Medizintechnik und Technomathematik an der Fachhochschule Aachen : vom 8. November 2019}, organization = {FH Aachen}, pages = {14 Seiten}, year = {2019}, language = {de} } @article{StaeudleSeynnesLapsetal.2022, author = {St{\"a}udle, Benjamin and Seynnes, Olivier and Laps, Guido and Br{\"u}ggemann, Gert-Peter and Albracht, Kirsten}, title = {Altered gastrocnemius contractile behavior in former achilles tendon rupture patients during walking}, series = {Frontiers in Physiology}, volume = {13}, journal = {Frontiers in Physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2022.792576}, pages = {12 Seiten}, year = {2022}, abstract = {Achilles tendon rupture (ATR) remains associated with functional limitations years after injury. Architectural remodeling of the gastrocnemius medialis (GM) muscle is typically observed in the affected leg and may compensate force deficits caused by a longer tendon. Yet patients seem to retain functional limitations during—low-force—walking gait. To explore the potential limits imposed by the remodeled GM muscle-tendon unit (MTU) on walking gait, we examined the contractile behavior of muscle fascicles during the stance phase. In a cross-sectional design, we studied nine former patients (males; age: 45 ± 9 years; height: 180 ± 7 cm; weight: 83 ± 6 kg) with a history of complete unilateral ATR, approximately 4 years post-surgery. Using ultrasonography, GM tendon morphology, muscle architecture at rest, and fascicular behavior were assessed during walking at 1.5 m⋅s-1 on a treadmill. Walking patterns were recorded with a motion capture system. The unaffected leg served as control. Lower limbs kinematics were largely similar between legs during walking. Typical features of ATR-related MTU remodeling were observed during the stance sub-phases corresponding to series elastic element (SEE) lengthening (energy storage) and SEE shortening (energy release), with shorter GM fascicles (36 and 36\%, respectively) and greater pennation angles (8° and 12°, respectively). However, relative to the optimal fascicle length for force production, fascicles operated at comparable length in both legs. Similarly, when expressed relative to optimal fascicle length, fascicle contraction velocity was not different between sides, except at the time-point of peak series elastic element (SEE) length, where it was 39 ± 49\% lower in the affected leg. Concomitantly, fascicles rotation during contraction was greater in the affected leg during the whole stance-phase, and architectural gear ratios (AGR) was larger during SEE lengthening. Under the present testing conditions, former ATR patients had recovered a relatively symmetrical walking gait pattern. Differences in seen AGR seem to accommodate the profound changes in MTU architecture, limiting the required fascicle shortening velocity. Overall, the contractile behavior of the GM fascicles does not restrict length- or velocity-dependent force potentials during this locomotor task.}, language = {en} } @article{QuittmannAbelAlbrachtetal.2022, author = {Quittmann, Oliver J. and Abel, Thomas and Albracht, Kirsten and Str{\"u}der, Heiko K.}, title = {Biomechanics of all-out handcycling exercise: kinetics, kinematics and muscular activity of a 15-s sprint test in able-bodied participants}, series = {Sports Biomechanics}, volume = {21}, journal = {Sports Biomechanics}, number = {10}, publisher = {Taylor \& Francis}, address = {London}, issn = {1752-6116 (Onlineausgabe)}, doi = {10.1080/14763141.2020.1745266}, pages = {1200 -- 1223}, year = {2022}, abstract = {This study aims to quantify the kinematics, kinetics and muscular activity of all-out handcycling exercise and examine their alterations during the course of a 15-s sprint test. Twelve able-bodied competitive triathletes performed a 15-s all-out sprint test in a recumbent racing handcycle that was attached to an ergometer. During the sprint test, tangential crank kinetics, 3D joint kinematics and muscular activity of 10 muscles of the upper extremity and trunk were examined using a power metre, motion capturing and surface electromyography (sEMG), respectively. Parameters were compared between revolution one (R1), revolution two (R2), the average of revolution 3 to 13 (R3) and the average of the remaining revolutions (R4). Shoulder abduction and internal-rotation increased, whereas maximal shoulder retroversion decreased during the sprint. Except for the wrist angles, angular velocity increased for every joint of the upper extremity. Several muscles demonstrated an increase in muscular activation, an earlier onset of muscular activation in crank cycle and an increased range of activation. During the course of a 15-s all-out sprint test in handcycling, the shoulder muscles and the muscles associated to the push phase demonstrate indications for short-duration fatigue. These findings are helpful to prevent injuries and improve performance in all-out handcycling.}, language = {en} } @article{RichterBraunsteinStaeudleetal.2021, author = {Richter, Charlotte and Braunstein, Bj{\"o}rn and St{\"a}udle, Benjamin and Attias, Julia and S{\"u}ss, Alexander and Weber, Tobias and Mileva, Katya N. and Rittweger, J{\"o}rn and Green, David A. and Albracht, Kirsten}, title = {Gastrocnemius medialis contractile behavior during running differs between simulated Lunar and Martian gravities}, series = {Scientific reports}, volume = {11}, journal = {Scientific reports}, number = {Article number: 22555}, publisher = {Springer Nature}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-021-00527-9}, pages = {13 Seiten}, year = {2021}, abstract = {The international partnership of space agencies has agreed to proceed forward to the Moon sustainably. Activities on the Lunar surface (0.16 g) will allow crewmembers to advance the exploration skills needed when expanding human presence to Mars (0.38 g). Whilst data from actual hypogravity activities are limited to the Apollo missions, simulation studies have indicated that ground reaction forces, mechanical work, muscle activation, and joint angles decrease with declining gravity level. However, these alterations in locomotion biomechanics do not necessarily scale to the gravity level, the reduction in gastrocnemius medialis activation even appears to level off around 0.2 g, while muscle activation pattern remains similar. Thus, it is difficult to predict whether gastrocnemius medialis contractile behavior during running on Moon will basically be the same as on Mars. Therefore, this study investigated lower limb joint kinematics and gastrocnemius medialis behavior during running at 1 g, simulated Martian gravity, and simulated Lunar gravity on the vertical treadmill facility. The results indicate that hypogravity-induced alterations in joint kinematics and contractile behavior still persist between simulated running on the Moon and Mars. This contrasts with the concept of a ceiling effect and should be carefully considered when evaluating exercise prescriptions and the transferability of locomotion practiced in Lunar gravity to Martian gravity.}, language = {en} } @article{WerkhausenWillwacherAlbracht2021, author = {Werkhausen, Amelie and Willwacher, Steffen and Albracht, Kirsten}, title = {Medial gastrocnemius muscle fascicles shorten throughout stance during sprint acceleration}, series = {Scandinavian Journal of Medicine \& Science in Sports}, volume = {31}, journal = {Scandinavian Journal of Medicine \& Science in Sports}, number = {7}, publisher = {Wiley-Blackwell}, address = {Oxford}, issn = {0905-7188 (Druckausgabe)}, doi = {10.1111/sms.13956}, pages = {1471 -- 1480}, year = {2021}, abstract = {The compliant nature of distal limb muscle-tendon units is traditionally considered suboptimal in explosive movements when positive joint work is required. However, during accelerative running, ankle joint net mechanical work is positive. Therefore, this study aims to investigate how plantar flexor muscle-tendon behavior is modulated during fast accelerations. Eleven female sprinters performed maximum sprint accelerations from starting blocks, while gastrocnemius muscle fascicle lengths were estimated using ultrasonography. We combined motion analysis and ground reaction force measurements to assess lower limb joint kinematics and kinetics, and to estimate gastrocnemius muscle-tendon unit length during the first two acceleration steps. Outcome variables were resampled to the stance phase and averaged across three to five trials. Relevant scalars were extracted and analyzed using one-sample and two-sample t-tests, and vector trajectories were compared using statistical parametric mapping. We found that an uncoupling of muscle fascicle behavior from muscle-tendon unit behavior is effectively used to produce net positive mechanical work at the joint during maximum sprint acceleration. Muscle fascicles shortened throughout the first and second steps, while shortening occurred earlier during the first step, where negative joint work was lower compared with the second step. Elastic strain energy may be stored during dorsiflexion after touchdown since fascicles did not lengthen at the same time to dissipate energy. Thus, net positive work generation is accommodated by the reuse of elastic strain energy along with positive gastrocnemius fascicle work. Our results show a mechanism of how muscles with high in-series compliance can contribute to net positive joint work.}, language = {en} } @article{MontiWaldvogelRitzmannetal.2021, author = {Monti, Elena and Waldvogel, Janice and Ritzmann, Ramona and Freyler, Kathrin and Albracht, Kirsten and Helm, Michael and De Cesare, Niccol{\`o} and Pavan, Piero and Reggiani, Carlo and Gollhofer, Albert and Narici, Marco Vincenzo}, title = {Muscle in variable gravity: "I do not know where I am, but I know what to do"}, series = {Frontiers in Physiology}, volume = {12}, journal = {Frontiers in Physiology}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2021.714655}, pages = {19 Seiten}, year = {2021}, abstract = {Performing tasks, such as running and jumping, requires activation of the agonist and antagonist muscles before (motor unit pre-activation) and during movement performance (Santello and Mcdonagh, 1998). A well-timed and regulated muscle activation elicits a stretch-shortening cycle (SSC) response, naturally occurring in bouncing movements (Ishikawa and Komi, 2004; Taube et al., 2012). By definition, the SSC describes the stretching of a pre-activated muscle-tendon complex immediately followed by a muscle shortening in the concentric push-off phase (Komi, 1984). Given the importance of SSC actions for human movement, it is not surprising that many studies investigated the biomechanics of this phenomenon; in particular, drop jumps (DJs) represent a good paradigm to study muscle fascicle and tendon behavior in ballistic movements involving the SSC. Within a DJ, three main phases [pre-activation, braking, and push-off (PO; Komi, 2000)] have been recognized and extensively studied in common and challenging conditions, such as changes in load, falling height, or simulated hypo-gravity (Avela et al., 1994; Arampatzis et al., 2001; Fukashiro et al., 2005; Ishikawa et al., 2005; Sousa et al., 2007; Ritzmann et al., 2016; Helm et al., 2020). These studies show that the timing and amount of triceps-surae muscle-tendon unit pre-activation in DJs are differentially regulated based on the load applied to the muscle, being optimal in normal "Earth" gravity conditions (Avela et al., 1994), but decreased in simulated hypo-gravity, hyper-gravity (Avela et al., 1994; Ritzmann et al., 2016), or unknown conditions (i.e., unknown falling heights; Helm et al., 2020). Some authors indicated that, when falling from heights different from the optimal one [defined as the drop height giving a maximum DJ performance indicated as peak ground reaction force (GRF) or jump high], electromyographic (EMG) activity of the plantar flexors increases from lower than optimal to higher than optimal heights (Ishikawa and Komi, 2004; Sousa et al., 2007). These findings highlight the ability of the central nervous system to regulate the timing and amount of pre-activation according to different jumping conditions, thus regulating muscle fascicle length, tendon and joint stiffness as well as position, in order to safely land on the ground and quickly re-bounce. Similarly, to pre-activation, also in the braking phase, the plantar flexors are differentially regulated. In optimal height (i.e., load) jumping conditions, gastrocnemius medialis (GM) fascicles shorten at early ground contact (possibly due to the intervention of the stretch reflex; Gollhofer et al., 1992) and behave quasi-isometrically in the late braking phase, enabling tendon elongation, and storage of elastic energy (Gollhofer et al., 1992; Fukashiro et al., 2005; Sousa et al., 2007). When increasing the falling height (augmenting the impact GRF), the quasi-isometric behavior of fascicles disappears, and fast fascicle lengthening occurs (Ishikawa et al., 2005; Sousa et al., 2007). In the third and last PO phase, fascicles shorten and the tendon releases the elastic energy previously stored. Bobbert et al. (1987) reported no influence of jumping height on the work done and on the net vertical impulse assessed during PO; this observation suggests that, despite an optimal DJ performance might be achieved only in specific conditions (falling heights, loads), the central nervous system seems to be able to regulate muscle behavior in order to effectively perform the required task also in challenging situations. Although the regulation of triceps-surae muscle-tendon unit in DJs has been extensively investigated, very few studies focused on sarcomeres behavior during the performance of this SSC movement (Kurokawa et al., 2003; Fukashiro et al., 2005, 2006). Sarcomeres represent muscle contractile units and are known to express different amounts of force depending on their length (Gordon et al., 1966; Walker and Schrodt, 1974); thus, understanding the time course of their responses during DJs is fundamental to gain further insights into muscle force-generating capacity. In vivo measurement of sarcomere length in humans has been so far been performed only in static positions and under highly controlled experimental conditions (Llewellyn et al., 2008; Sanchez et al., 2015). Instead, human sarcomere length estimation (achieved by dividing GM measured fascicle length for a fixed sarcomere number) in dynamic contractions provided an indirect measure of sarcomere operating range during squat jump, countermovement jump, and DJ (Fukashiro et al., 2005, 2006; Kurokawa et al., 2003). The results of these studies showed that sarcomeres operate in the ascending limb of their length-tension (L-T) relationship in all types of jumps, and particularly so in DJ. However, most of the available observations on sarcomere and muscle fascicle behavior were made in condition of constant gravity. Thus, in order to understand how sarcomere and muscle fascicle length are regulated in variable gravity conditions, we performed experiments in a parabolic flight, involving variable gravity levels, ranging from about zero-g to about double the Earth's gravity (1 g; Waldvogel et al., 2021). Specifically, the aims of the present study were as follows: 1. To investigate the ability of the neuromuscular system in regulating fascicle length in response to conditions of variable gravity. 2. To estimate sarcomere operative length in the different DJ phases, in order to calculate its theoretical force production and its possible modulation in conditions of variable gravity. We hypothesized that muscle fascicles would be differentially regulated in different gravity conditions compared to 1 g, particularly in anticipation of landing and re-bouncing in unknown gravity levels. In addition, we hypothesized that sarcomeres would operate in the upper part of the ascending limb of their L-T relationship, possibly lengthening during the braking phase (especially in hyper-gravity) while operating quasi-isometrically in 1 g.}, language = {en} } @article{StaeudleSeynnesLapsetal.2021, author = {St{\"a}udle, Benjamin and Seynnes, Olivier and Laps, Guido and G{\"o}ll, Fabian and Br{\"u}ggemann, Gert-Peter and Albracht, Kirsten}, title = {Recovery from achilles tendon repair: a combination of Postsurgery Outcomes and Insufficient remodeling of muscle and tendon}, series = {Medicine \& Science in Sports \& Exercise}, volume = {53}, journal = {Medicine \& Science in Sports \& Exercise}, number = {7}, publisher = {American College of Sports Medicine}, address = {Philadelphia, Pa.}, issn = {1530-0315}, doi = {10.1249/MSS.0000000000002592}, pages = {1356 -- 1366}, year = {2021}, abstract = {Achilles tendon rupture (ATR) patients have persistent functional deficits in the triceps surae muscle-tendon unit (MTU). The complex remodeling of the MTU accompanying these deficits remains poorly understood. The purpose of the present study was to associate in vivo and in silico data to investigate the relations between changes inMTU properties and strength deficits inATR patients. Methods: Elevenmale subjects who had undergone surgical repair of complete unilateral ATR were examined 4.6 ± 2.0 (mean ± SD) yr after rupture. Gastrocnemius medialis (GM) tendon stiffness, morphology, and muscle architecture were determined using ultrasonography. The force-length relation of the plantar flexor muscles was assessed at five ankle joint angles. In addition, simulations (OpenSim) of the GM MTU force-length properties were performed with various iterations of MTU properties found between the unaffected and the affected side. Results: The affected side of the patients displayed a longer, larger, and stiffer GM tendon (13\% ± 10\%, 105\% ± 28\%, and 54\% ± 24\%, respectively) compared with the unaffected side. The GM muscle fascicles of the affected side were shorter (32\% ± 12\%) and with greater pennation angles (31\% ± 26\%). A mean deficit in plantarflexion moment of 31\% ± 10\% was measured. Simulations indicate that pairing an intact muscle with a longer tendon shifts the optimal angular range of peak force outside physiological angular ranges, whereas the shorter muscle fascicles and tendon stiffening seen in the affected side decrease this shift, albeit incompletely. Conclusions: These results suggest that the substantial changes in MTU properties found in ATR patients may partly result from compensatory remodeling, although this process appears insufficient to fully restore muscle function.}, language = {en} } @incollection{Dreschers2023, author = {Dreschers, Martin}, title = {\S25 Arbeitsrechtliche Probleme im Rahmen der Betriebsfortf{\"u}hrung}, series = {Betriebsfortf{\"u}hrung in Restrukturierung und Insolvenz}, booktitle = {Betriebsfortf{\"u}hrung in Restrukturierung und Insolvenz}, editor = {M{\"o}nning, Rolf-Dieter}, publisher = {RWS Verlag}, address = {K{\"o}ln}, isbn = {978-3-8145-2012-4 (print)}, doi = {https://doi.org/10.15375/9783814558882-028}, pages = {947 -- 988}, year = {2023}, language = {de} } @incollection{Dreschers2023, author = {Dreschers, Martin}, title = {\S18 Grenz{\"u}berschreitende Eigenverwaltung}, series = {HRI II - Handbuch Restrukturierung in der Insolvenz}, booktitle = {HRI II - Handbuch Restrukturierung in der Insolvenz}, editor = {K{\"u}bler, Bruno M. and Bork, Reinhard and Pr{\"u}tting, Hanns}, publisher = {RWS Verlag}, address = {K{\"o}ln}, isbn = {978-3-8145-2010-0 (print)}, doi = {10.15375/9783814558714-028}, pages = {524 -- 556}, year = {2023}, language = {de} } @article{WerkhausenAlbrachtCroninetal.2018, author = {Werkhausen, Amelie and Albracht, Kirsten and Cronin, Neil J and Paulsen, G{\o}ran and Bojsen-M{\o}ller, Jens and Seynnes, Olivier R}, title = {Effect of training-induced changes in achilles tendon stiffness on muscle-tendon behavior during landing}, series = {Frontiers in physiology}, journal = {Frontiers in physiology}, number = {9}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1664-042X}, doi = {10.3389/fphys.2018.00794}, pages = {11 Seiten}, year = {2018}, abstract = {During rapid deceleration of the body, tendons buffer part of the elongation of the muscle-tendon unit (MTU), enabling safe energy dissipation via eccentric muscle contraction. Yet, the influence of changes in tendon stiffness within the physiological range upon these lengthening contractions is unknown. This study aimed to examine the effect of training-induced stiffening of the Achilles tendon on triceps surae muscle-tendon behavior during a landing task. Twenty-one male subjects were assigned to either a 10-week resistance-training program consisting of single-leg isometric plantarflexion (n = 11) or to a non-training control group (n = 10). Before and after the training period, plantarflexion force, peak Achilles tendon strain and stiffness were measured during isometric contractions, using a combination of dynamometry, ultrasound and kinematics data. Additionally, testing included a step-landing task, during which joint mechanics and lengths of gastrocnemius and soleus fascicles, Achilles tendon, and MTU were determined using synchronized ultrasound, kinematics and kinetics data collection. After training, plantarflexion strength and Achilles tendon stiffness increased (15 and 18\%, respectively), and tendon strain during landing remained similar. Likewise, lengthening and negative work produced by the gastrocnemius MTU did not change detectably. However, in the training group, gastrocnemius fascicle length was offset (8\%) to a longer length at touch down and, surprisingly, fascicle lengthening and velocity were reduced by 27 and 21\%, respectively. These changes were not observed for soleus fascicles when accounting for variation in task execution between tests. These results indicate that a training-induced increase in tendon stiffness does not noticeably affect the buffering action of the tendon when the MTU is rapidly stretched. Reductions in gastrocnemius fascicle lengthening and lengthening velocity during landing occurred independently from tendon strain. Future studies are required to provide insight into the mechanisms underpinning these observations and their influence on energy dissipation.}, language = {en} } @article{YangKriechbaumerAlbrachtetal.2014, author = {Yang, Peng-Fei and Kriechbaumer, Andreas and Albracht, Kirsten and Sanno, Maximilian and Ganse, Bergita and Koy, Timmo and Shang, Peng and br{\"u}ggemann, Gert-Peter and M{\"u}ller, Lars Peter and Rittweger, J{\"o}rn}, title = {A novel optical approach for assessing in vivo bone segment deformation and its application in muscle-bone relationship studies in humans}, series = {Journal of Orthopaedic Translation}, volume = {2}, journal = {Journal of Orthopaedic Translation}, number = {4}, publisher = {Elsevier}, address = {Singapore}, issn = {2214-0328}, doi = {10.1016/j.jot.2014.07.078}, pages = {238 -- 238}, year = {2014}, language = {en} } @misc{OPUS4-10951, title = {Richtlinie zur Durchf{\"u}hrung von Sonderveranstaltungen in den Geb{\"a}uden und Liegenschaften der FH Aachen (Veranstaltungsrichtlinie) : vom 20. November 2019}, organization = {FH Aachen}, pages = {21 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10952, title = {Richtlinie zur Durchf{\"u}hrung von Sonderveranstaltungen in den Geb{\"a}uden und Liegenschaften der FH Aachen (Veranstaltungsrichtlinie) : vom 20. November 2019 Anlage 1 aktualisiert am 22. Januar 2020}, organization = {FH Aachen}, pages = {21 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10953, title = {Richtlinie f{\"u}r die Besch{\"a}ftigung und Verg{\"u}tung studentischer und wissenschaftlicher Hilfskr{\"a}fte an der Fachhochschule Aachen : vom 20. November 2019}, organization = {FH Aachen}, pages = {6 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10954, title = {Richtlinie f{\"u}r die Besch{\"a}ftigung und Verg{\"u}tung studentischer und wissenschaftlicher Hilfskr{\"a}fte an der Fachhochschule Aachen : vom 20. November 2019 aktualisiert am 24. November 2022}, organization = {FH Aachen}, pages = {6 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10955, title = {Gleichstellungsquoten der FH Aachen f{\"u}r die Jahre 2019 -2021 : vom 20. November 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10956, title = {Ordnung zur Aufhebung der Pr{\"u}fungsordnungen f{\"u}r den Masterstudiengang „Nuclear Applications" vom 13. Februar 2004 (FH-Mitteilung Nr. 5/2004) und vom 25. Februar 2010 (FH-Mitteilung Nr. 15/2010) in den Fassungen der Bekanntmachung der {\"A}nderungsordnungen vom 6. November 2012 (FH-Mitteilung Nr. 120/2012), 18. Juni 2014 (FH- Mitteilung Nr. 72/2014) und vom 15. Juni 2015 (FH-Mitteilung Nr. 28/2015) : vom 29. November 2019}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10957, title = {5. Ordnung zur {\"A}nderung der Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge „Betriebswirtschaft Praxis Plus" und „Betriebswirtschaft Praxis Plus (Teilzeit)" mit dem Studienabschluss „Bachelor of Science" am Fachbereich Wirtschaftswissenschaften der Fachhochschule Aachen (PO - BWL Praxis Plus) : vom 29. November 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10958, title = {Pr{\"u}fungsordnung f{\"u}r die Bachelorstudieng{\"a}nge „Betriebswirtschaft Praxis Plus" und „Betriebswirtschaft Praxis Plus (Teilzeit)" mit dem Studienabschluss „Bachelor of Science" am Fachbereich Wirtschaftswissenschaften der Fachhochschule Aachen (PO-BWL Praxis Plus) : vom 14. Januar 2014 - FH-Mitteilung Nr. 2/2014 in der Fassung der Bekanntmachung der {\"A}nderungsordnung vom 29. November 2019 - FH-Mitteilung Nr. 128/2019 (Nichtamtliche lesbare Fassung | Studienbeginn ab WS 2019/20)}, organization = {FH Aachen}, pages = {11 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10959, title = {2. {\"A}nderung der Richtlinie des Rektorats der FH Aachen f{\"u}r die Vergabe von Lehrveranstaltungspr{\"a}mien : vom 13. Dezember 2019}, organization = {FH Aachen}, pages = {2 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10960, title = {Richtlinie des Rektorats der FH Aachen f{\"u}r die Vergabe von Lehrveranstaltungspr{\"a}mien : vom 16. Juli 2012 - FH-Mitteilung Nr. 68/2012 in der Fassung der Bekanntmachung der {\"A}nderung vom 13. Dezember 2019 - FH-Mitteilung Nr. 130/2019 (Nichtamtliche lesbare Fassung)}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10961, title = {Pr{\"u}fungsordnung f{\"u}r den Masterstudiengang Nuclear Applications im Fachbereich Chemie und Biotechnologie an der Fachhochschule Aachen : vom 17. Dezember 2019}, organization = {FH Aachen}, pages = {7 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10962, title = {Ordnung zur Aufhebung der Pr{\"u}fungsordnung f{\"u}r den Masterstudiengang „Information Systems Engineering" vom 22. Januar 2010 (FH-Mitteilung Nr. 5/2010), zuletzt ge{\"a}ndert durch {\"A}nderungsordnung vom 4. Februar 2013 (FH-Mitteilung Nr. 6/2013) : vom 20. Dezember 2019}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10963, title = {Ordnung zur Aufhebung der Pr{\"u}fungsordnung f{\"u}r den Masterstudiengang „Elektrotechnik" (zuvor „Nachrichtentechnik" und „Elektrotechnik und Informationstechnik") vom 22. Januar 2010 (FH-Mitteilung Nr. 7/2010), zuletzt ge{\"a}ndert durch {\"A}nderungsordnung vom 25. April 2016 (FH-Mitteilung Nr. 31/2016) : vom 20. Dezember 2019}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2019}, language = {de} } @misc{OPUS4-10964, title = {Ordnung zur Aufhebung der Pr{\"u}fungsordnung f{\"u}r die Masterstudieng{\"a}nge „Energiewirtschaft \& Informatik" (3 Semester) und „Energiewirtschaft \& Informatik" (4 Semester) vom 4. Mai 2016 (FH-Mitteilung Nr. 59/2016) Fachbereich Energietechnik Fachbereich Medizintechnik und Technomathematik an der Fachhochschule Aachen : vom 16. Januar 2020}, organization = {FH Aachen}, pages = {3 Seiten}, year = {2020}, language = {de} } @misc{OPUS4-10965, title = {Verwaltungs- und Benutzungsordnung des Solar-Instituts J{\"u}lich (SIJ) : vom 27. Januar 2020}, organization = {FH Aachen}, pages = {5 Seiten}, year = {2020}, language = {de} } @misc{OPUS4-10966, title = {Verwaltungs- und Benutzungsordnung des Solar-Instituts J{\"u}lich (SIJ) vom 27. Januar 2020 : berichtigt durch Bekanntmachung vom 18. M{\"a}rz 2020 (FH-Mitteilung Nr. 27/2020)}, organization = {FH Aachen}, pages = {5 Seiten}, year = {2020}, language = {de} } @inproceedings{MaurerMiskiwAcostaetal.2023, author = {Maurer, Florian and Miskiw, Kim K. and Acosta, Rebeca Ramirez and Harder, Nick and Sander, Volker and Lehnhoff, Sebastian}, title = {Market abstraction of energy markets and policies - application in an agent-based modeling toolbox}, series = {EI.A 2023: Energy Informatics}, booktitle = {EI.A 2023: Energy Informatics}, editor = {Jorgensen, Bo Norregaard and Pereira da Silva, Luiz Carlos and Ma, Zheng}, publisher = {Springer}, address = {Cham}, isbn = {978-3-031-48651-7 (Print)}, doi = {10.1007/978-3-031-48652-4_10}, pages = {139 -- 157}, year = {2023}, abstract = {In light of emerging challenges in energy systems, markets are prone to changing dynamics and market design. Simulation models are commonly used to understand the changing dynamics of future electricity markets. However, existing market models were often created with specific use cases in mind, which limits their flexibility and usability. This can impose challenges for using a single model to compare different market designs. This paper introduces a new method of defining market designs for energy market simulations. The proposed concept makes it easy to incorporate different market designs into electricity market models by using relevant parameters derived from analyzing existing simulation tools, morphological categorization and ontologies. These parameters are then used to derive a market abstraction and integrate it into an agent-based simulation framework, allowing for a unified analysis of diverse market designs. Furthermore, we showcase the usability of integrating new types of long-term contracts and over-the-counter trading. To validate this approach, two case studies are demonstrated: a pay-as-clear market and a pay-as-bid long-term market. These examples demonstrate the capabilities of the proposed framework.}, language = {en} } @techreport{AlbrachtRitzmannKrameretal.2017, author = {Albracht, Kirsten and Ritzmann, Ramona and Kramer, Andreas and Meskemper, Joshua and St{\"a}udle, Benjamin and K{\"u}mmel, Jacob and Freyler, Katrin and Felsenberg, Dieter and Gruber, Marksu and Gollhofer, Albert and Belavy, Daniel}, title = {Vorhaben: Muskelkraftgenerierungsf{\"a}higkeit in Mikrogravitation}, publisher = {Deutsche Sporthochschule K{\"o}ln}, address = {Kl{\"o}n}, doi = {10.2314/KXP:1670327353}, pages = {23 Seiten}, year = {2017}, language = {de} } @inproceedings{SchulzeBuxlohGross2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz}, title = {Interdisciplinary Course Smart Building Engineering: A new approach of teaching freshmen in remote teamwork project under pandemic restrictions}, series = {New Perspectives in Science Education - International Conference}, booktitle = {New Perspectives in Science Education - International Conference}, publisher = {Filodiritto}, address = {Bologna}, pages = {4 Seiten}, year = {2021}, abstract = {In the context of the Corona pandemic and its impact on teaching like digital lectures and exercises a new concept especially for freshmen in demanding courses of Smart Building Engineering became necessary. As there were hardly any face-to-face events at the university, the new teaching concept should enable a good start into engineering studies under pandemic conditions anyway and should also replace the written exam at the end. The students should become active themselves in small teams instead of listening passively to a lecture broadcast online with almost no personal contact. For this purpose, a role play was developed in which the freshmen had to work out a complete solution to the realistic problem of designing, construction planning and implementing a small guesthouse. Each student of the team had to take a certain role like architect, site manager, BIM-manager, electrician and the technitian for HVAC installations. Technical specifications must be complied with, as well as documentation, time planning and cost estimate. The final project folder had to contain technical documents like circuit diagrams for electrical components, circuit diagrams for water and heating, design calculations and components lists. On the other hand construction schedule, construction implementation plan, documentation of the construction progress and minutes of meetings between the various trades had to be submitted as well. In addition to the project folder, a model of the construction project must also be created either as a handmade model or as a digital 3D-model using Computer-aided design (CAD) software. The first steps in the field of Building information modelling (BIM) had also been taken by creating a digital model of the building showing the current planning status in real time as a digital twin. This project turned out to be an excellent training of important student competencies like teamwork, communication skills, and self -organisation and also increased motivation to work on complex technical questions. The aim of giving the student a first impression on the challenges and solutions in building projects with many different technical trades and their points of view was very well achieved and should be continued in the future.}, language = {en} } @inproceedings{SchulzeBuxlohGross2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz}, title = {Miniature urban farming plant: a complex educational "Toy" for engineering students}, series = {The Future of Education 11th Edition 2021}, booktitle = {The Future of Education 11th Edition 2021}, pages = {4 Seiten}, year = {2021}, abstract = {Urban farming is an innovative and sustainable way of food production and is becoming more and more important in smart city and quarter concepts. It also enables the production of certain foods in places where they usually dare not produced, such as production of fish or shrimps in large cities far away from the coast. Unfortunately, it is not always possible to show students such concepts and systems in real life as part of courses: visits of such industry plants are sometimes not possible because of distance or are permitted by the operator for hygienic reasons. In order to give the students the opportunity of getting into contact with such an urban farming system and its complex operation, an industrial urban farming plant was set up on a significantly smaller scale. Therefore, all needed technical components like water aeriation, biological and mechanical filtration or water circulation have been replaced either by aquarium components or by self-designed parts also using a 3D-printer. Students from different courses like mechanical engineering, smart building engineering, biology, electrical engineering, automation technology and civil engineering were involved in this project. This "miniature industrial plant" was also able to start operation and has now been running for two years successfully. Due to Corona pandemic, home office and remote online lectures, the automation of this miniature plant should be brought to a higher level in future for providing a good control over the system and water quality remotely. The aim of giving the student a chance to get to know the operation of an urban farming plant was very well achieved and the students had lots of fun in "playing" and learning with it in a realistic way.}, language = {en} } @inproceedings{SchulzeBuxlohGrossUlbrich2021, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz and Ulbrich, Michelle}, title = {Digital planning using building information modelling and virtual reality: new approach for students' remote practical training under lockdown conditions in the course of smart building engineering}, series = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, booktitle = {Proceedings of International Conference on Education in Mathematics, Science and Technology 2021}, publisher = {ISTES Organization}, address = {San Antonio, TX}, isbn = {978-1-952092-17-6}, pages = {118 -- 123}, year = {2021}, abstract = {The worldwide Corona pandemic has severely restricted student projects in the higher semesters of engineering courses. In order not to delay the graduation, a new concept had to be developed for projects under lockdown conditions. Therefore, unused rooms at the university should be digitally recorded in order to develop a new usage concept as laboratory rooms. An inventory of the actual state of the rooms was done first by taking photos and listing up all flaws and peculiarities. After that, a digital site measuring was done with a 360° laser scanner and these recorded scans were linked to a coherent point cloud and transferred to a software for planning technical building services and supporting Building Information Modelling (BIM). In order to better illustrate the difference between the actual and target state, two virtual reality models were created for realistic demonstration. During the project, the students had to go through the entire digital planning phases. Technical specifications had to be complied with, as well as documentation, time planning and cost estimate. This project turned out to be an excellent alternative to on-site practical training under lockdown conditions and increased the students' motivation to deal with complex technical questions.}, language = {en} } @misc{SchulzeBuxlohGrossCheng2020, author = {Schulze-Buxloh, Lina and Groß, Rolf Fritz and Cheng, Kevin Toni}, title = {Development and manufacturing of an interactive three-dimensional phase diagram of carbon dioxide for teaching sessions in thermodynamics}, series = {Proceedings of the International Conference The Future of Education 2020}, journal = {Proceedings of the International Conference The Future of Education 2020}, year = {2020}, language = {en} } @inproceedings{BedburMoorkampPetersonetal.2020, author = {Bedbur, Christian and Moorkamp, Wilfried and Peterson, Leif Arne and Uibel, Thomas}, title = {Holzbr{\"u}cken mit Natursteinbel{\"a}gen - Untersuchungen zur Aktivierung der Verbundwirkung}, series = {Doktorandenkolloquium Holzbau Forschung + Praxis 2020}, booktitle = {Doktorandenkolloquium Holzbau Forschung + Praxis 2020}, editor = {Kuhlmann, Ulrike}, publisher = {Universit{\"a}t Stuttgart, Institut f{\"u}r Konstruktion und Entwurf}, address = {Stuttgart}, pages = {53 -- 60}, year = {2020}, language = {de} } @article{AngermannGuenthnerHanssenetal.2022, author = {Angermann, Susanne and G{\"u}nthner, Roman and Hanssen, Henner and Lorenz, Georg and Braunisch, Matthias C. and Steubl, Dominik and Matschkal, Julia and Kemmner, Stephan and Hausinger, Renate and Block, Zenonas and Haller, Bernhard and Heemann, Uwe and Kotliar, Konstantin and Grimmer, Timo and Schmaderer, Christoph}, title = {Cognitive impairment and microvascular function in end-stage renal disease}, series = {International Journal of Methods in Psychiatric Research (MPR)}, volume = {31}, journal = {International Journal of Methods in Psychiatric Research (MPR)}, number = {2}, publisher = {Wiley}, issn = {1049-8931 (Print)}, doi = {10.1002/mpr.1909}, pages = {1 -- 10}, year = {2022}, abstract = {Objective Hemodialysis patients show an approximately threefold higher prevalence of cognitive impairment compared to the age-matched general population. Impaired microcirculatory function is one of the assumed causes. Dynamic retinal vessel analysis is a quantitative method for measuring neurovascular coupling and microvascular endothelial function. We hypothesize that cognitive impairment is associated with altered microcirculation of retinal vessels. Methods 152 chronic hemodialysis patients underwent cognitive testing using the Montreal Cognitive Assessment. Retinal microcirculation was assessed by Dynamic Retinal Vessel Analysis, which carries out an examination recording retinal vessels' reaction to a flicker light stimulus under standardized conditions. Results In unadjusted as well as in adjusted linear regression analyses a significant association between the visuospatial executive function domain score of the Montreal Cognitive Assessment and the maximum arteriolar dilation as response of retinal arterioles to the flicker light stimulation was obtained. Conclusion This is the first study determining retinal microvascular function as surrogate for cerebral microvascular function and cognition in hemodialysis patients. The relationship between impairment in executive function and reduced arteriolar reaction to flicker light stimulation supports the involvement of cerebral small vessel disease as contributing factor for the development of cognitive impairment in this patient population and might be a target for noninvasive disease monitoring and therapeutic intervention.}, language = {en} } @article{KotliarOrtnerConradietal.2022, author = {Kotliar, Konstantin and Ortner, Marion and Conradi, Anna and Hacker, Patricia and Hauser, Christine and G{\"u}nthner, Roman and Moser, Michaela and Muggenthaler, Claudia and Diehl-Schmid, Janine and Priller, Josef and Schmaderer, Christoph and Grimmer, Timo}, title = {Altered retinal cerebral vessel oscillation frequencies in Alzheimer's disease compatible with impaired amyloid clearance}, series = {Neurobiology of Aging}, volume = {120}, journal = {Neurobiology of Aging}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0197-4580}, doi = {10.1016/j.neurobiolaging.2022.08.012}, pages = {117 -- 127}, year = {2022}, abstract = {Retinal vessels are similar to cerebral vessels in their structure and function. Moderately low oscillation frequencies of around 0.1 Hz have been reported as the driving force for paravascular drainage in gray matter in mice and are known as the frequencies of lymphatic vessels in humans. We aimed to elucidate whether retinal vessel oscillations are altered in Alzheimer's disease (AD) at the stage of dementia or mild cognitive impairment (MCI). Seventeen patients with mild-to-moderate dementia due to AD (ADD); 23 patients with MCI due to AD, and 18 cognitively healthy controls (HC) were examined using Dynamic Retinal Vessel Analyzer. Oscillatory temporal changes of retinal vessel diameters were evaluated using mathematical signal analysis. Especially at moderately low frequencies around 0.1 Hz, arterial oscillations in ADD and MCI significantly prevailed over HC oscillations and correlated with disease severity. The pronounced retinal arterial vasomotion at moderately low frequencies in the ADD and MCI groups would be compatible with the view of a compensatory upregulation of paravascular drainage in AD and strengthen the amyloid clearance hypothesis.}, language = {en} } @article{NeumaierWeissVeldemanetal.2021, author = {Neumaier, Felix and Weiss, Miriam and Veldeman, Michael and Kotliar, Konstantin and Wiesmann, Martin and Schulze-Steinen, Henna and H{\"o}llig, Anke and Clusmann, Hans and Schubert, Gerrit Alexander and Albanna, Walid}, title = {Changes in endogenous daytime melatonin levels after aneurysmal subarachnoid hemorrhage - preliminary findings from an observational cohort study}, series = {Clinical Neurology and Neurosurgery}, volume = {208}, journal = {Clinical Neurology and Neurosurgery}, number = {Article No.: 106870}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0303-8467}, doi = {10.1016/j.clineuro.2021.106870}, year = {2021}, abstract = {Aneurysmal subarachnoid hemorrhage (aSAH) is associated with early and delayed brain injury due to several underlying and interrelated processes, which include inflammation, oxidative stress, endothelial, and neuronal apoptosis. Treatment with melatonin, a cytoprotective neurohormone with anti-inflammatory, anti-oxidant and anti-apoptotic effects, has been shown to attenuate early brain injury (EBI) and to prevent delayed cerebral vasospasm in experimental aSAH models. Less is known about the role of endogenous melatonin for aSAH outcome and how its production is altered by the pathophysiological cascades initiated during EBI. In the present observational study, we analyzed changes in melatonin levels during the first three weeks after aSAH.}, language = {en} } @article{AlnemerKotliarNeuhausetal.2023, author = {Alnemer, Momin Sami Mohammad and Kotliar, Konstantin and Neuhaus, Valentin and Pape, Hans-Christoph and Ciritsis, Bernhard D.}, title = {Cost-effectiveness analysis of surgical proximal femur fracture prevention in elderly: a Markov cohort simulation model}, series = {Cost Effectiveness and Resource Allocation}, journal = {Cost Effectiveness and Resource Allocation}, number = {21, Article number: 77}, publisher = {Springer Nature}, issn = {1478-7547}, doi = {10.1186/s12962-023-00482-4}, pages = {12 Seiten}, year = {2023}, abstract = {Background Hip fractures are a common and costly health problem, resulting in significant morbidity and mortality, as well as high costs for healthcare systems, especially for the elderly. Implementing surgical preventive strategies has the potential to improve the quality of life and reduce the burden on healthcare resources, particularly in the long term. However, there are currently limited guidelines for standardizing hip fracture prophylaxis practices. Methods This study used a cost-effectiveness analysis with a finite-state Markov model and cohort simulation to evaluate the primary and secondary surgical prevention of hip fractures in the elderly. Patients aged 60 to 90 years were simulated in two different models (A and B) to assess prevention at different levels. Model A assumed prophylaxis was performed during the fracture operation on the contralateral side, while Model B included individuals with high fracture risk factors. Costs were obtained from the Centers for Medicare \& Medicaid Services, and transition probabilities and health state utilities were derived from available literature. The baseline assumption was a 10\% reduction in fracture risk after prophylaxis. A sensitivity analysis was also conducted to assess the reliability and variability of the results. Results With a 10\% fracture risk reduction, model A costs between \$8,850 and \$46,940 per quality-adjusted life-year (\$/QALY). Additionally, it proved most cost-effective in the age range between 61 and 81 years. The sensitivity analysis established that a reduction of ≥ 2.8\% is needed for prophylaxis to be definitely cost-effective. The cost-effectiveness at the secondary prevention level was most sensitive to the cost of the contralateral side's prophylaxis, the patient's age, and fracture treatment cost. For high-risk patients with no fracture history, the cost-effectiveness of a preventive strategy depends on their risk profile. In the baseline analysis, the incremental cost-effectiveness ratio at the primary prevention level varied between \$11,000/QALY and \$74,000/QALY, which is below the defined willingness to pay threshold. Conclusion Due to the high cost of hip fracture treatment and its increased morbidity, surgical prophylaxis strategies have demonstrated that they can significantly relieve the healthcare system. Various key assumptions facilitated the modeling, allowing for adequate room for uncertainty. Further research is needed to evaluate health-state-associated risks.}, language = {en} } @article{KuchlerGuenthnerRibeiroetal.2023, author = {Kuchler, Timon and G{\"u}nthner, Roman and Ribeiro, Andrea and Hausinger, Renate and Streese, Lukas and W{\"o}hnl, Anna and Kesseler, Veronika and Negele, Johanna and Assali, Tarek and Carbajo-Lozoya, Javier and Lech, Maciej and Adorjan, Kristina and Stubbe, Hans Christian and Hanssen, Henner and Kotliar, Konstantin and Haller, Berhard and Heemann, Uwe and Schmaderer, Christoph}, title = {Persistent endothelial dysfunction in post-COVID-19 syndrome and its associations with symptom severity and chronic inflammation}, volume = {26}, publisher = {Springer Nature}, address = {Dordrecht}, doi = {10.1007/s10456-023-09885-6}, pages = {547 -- 563}, year = {2023}, abstract = {Background Post-COVID-19 syndrome (PCS) is a lingering disease with ongoing symptoms such as fatigue and cognitive impairment resulting in a high impact on the daily life of patients. Understanding the pathophysiology of PCS is a public health priority, as it still poses a diagnostic and treatment challenge for physicians. Methods In this prospective observational cohort study, we analyzed the retinal microcirculation using Retinal Vessel Analysis (RVA) in a cohort of patients with PCS and compared it to an age- and gender-matched healthy cohort (n = 41, matched out of n = 204). Measurements and main results PCS patients exhibit persistent endothelial dysfunction (ED), as indicated by significantly lower venular flicker-induced dilation (vFID; 3.42\% ± 1.77\% vs. 4.64\% ± 2.59\%; p = 0.02), narrower central retinal artery equivalent (CRAE; 178.1 [167.5-190.2] vs. 189.1 [179.4-197.2], p = 0.01) and lower arteriolar-venular ratio (AVR; (0.84 [0.8-0.9] vs. 0.88 [0.8-0.9], p = 0.007). When combining AVR and vFID, predicted scores reached good ability to discriminate groups (area under the curve: 0.75). Higher PCS severity scores correlated with lower AVR (R = - 0.37 p = 0.017). The association of microvascular changes with PCS severity were amplified in PCS patients exhibiting higher levels of inflammatory parameters. Conclusion Our results demonstrate that prolonged endothelial dysfunction is a hallmark of PCS, and impairments of the microcirculation seem to explain ongoing symptoms in patients. As potential therapies for PCS emerge, RVA parameters may become relevant as clinical biomarkers for diagnosis and therapy management.}, language = {en} } @article{KuertenKotliarFuestetal.2021, author = {Kuerten, David and Kotliar, Konstantin and Fuest, Matthias and Walter, Peter and Hollstein, Muriel and Plange, Niklas}, title = {Does hemispheric vascular regulation differ significantly in glaucoma patients with altitudinal visual field asymmetry? A single-center, prospective study}, series = {International Ophthalmology}, volume = {41}, journal = {International Ophthalmology}, number = {41}, editor = {Neri, Piergiorgio}, publisher = {Springer}, address = {Berlin}, isbn = {1573-2630}, doi = {10.1007/s10792-021-01876-0}, pages = {3109 -- 3119}, year = {2021}, abstract = {Purpose Vascular risk factors and ocular perfusion are heatedly discussed in the pathogenesis of glaucoma. The retinal vessel analyzer (RVA, IMEDOS Systems, Germany) allows noninvasive measurement of retinal vessel regulation. Significant differences especially in the veins between healthy subjects and patients suffering from glaucoma were previously reported. In this pilot-study we investigated if localized vascular regulation is altered in glaucoma patients with altitudinal visual field defect asymmetry. Methods 15 eyes of 12 glaucoma patients with advanced altitudinal visual field defect asymmetry were included. The mean defect was calculated for each hemisphere separately (-20.99 ± 10.49 pro- found hemispheric visual field defect vs -7.36 ± 3.97 dB less profound hemisphere). After pupil dilation, RVA measurements of retinal arteries and veins were conducted using the standard protocol. The superior and inferior retinal vessel reactivity were measured consecutively in each eye. Results Significant differences were recorded in venous vessel constriction after flicker light stimulation and overall amplitude of the reaction (p \ 0.04 and p \ 0.02 respectively) in-between the hemispheres spheres. Vessel reaction was higher in the hemisphere corresponding to the more advanced visual field defect. Arterial diameters reacted similarly, failing to reach statistical significance. Conclusion Localized retinal vessel regulation is significantly altered in glaucoma patients with asymmetri altitudinal visual field defects. Veins supplying the hemisphere concordant to a less profound visual field defect show diminished diameter changes. Vascular dysregulation might be particularly important in early glaucoma stages prior to a significant visual field defect.}, language = {en} } @article{AlbannaConzenWeissetal.2021, author = {Albanna, Walid and Conzen, Catharina and Weiss, Miriam and Seyfried, Katharina and Kotliar, Konstantin and Schmidt, Tobias Philip and Kuerten, David and Hescheler, J{\"u}rgen and Bruecken, Anne and Schmidt-Trucks{\"a}ss, Arno and Neumaier, Felix and Wiesmann, Martin and Clusmann, Hans and Schubert, Gerrit Alexander}, title = {Non-invasive assessment of neurovascular coupling after aneurysmal subarachnoid hemorrhage: a prospective observational trial using retinal vessel analysis}, series = {Frontiers in Neurology}, volume = {12}, journal = {Frontiers in Neurology}, number = {12}, issn = {1664-2295}, doi = {10.3389/fneur.2021.690183}, pages = {1 -- 15}, year = {2021}, abstract = {Delayed cerebral ischemia (DCI) is a common complication after aneurysmal subarachnoid hemorrhage (aSAH) and can lead to infarction and poor clinical outcome. The underlying mechanisms are still incompletely understood, but animal models indicate that vasoactive metabolites and inflammatory cytokines produced within the subarachnoid space may progressively impair and partially invert neurovascular coupling (NVC) in the brain. Because cerebral and retinal microvasculature are governed by comparable regulatory mechanisms and may be connected by perivascular pathways, retinal vascular changes are increasingly recognized as a potential surrogate for altered NVC in the brain. Here, we used non-invasive retinal vessel analysis (RVA) to assess microvascular function in aSAH patients at different times after the ictus.}, language = {en} } @incollection{Kotliar2021, author = {Kotliar, Konstantin}, title = {Ocular rigidity: clinical approach}, series = {Ocular Rigidity, Biomechanics and Hydrodynamics of the Eye}, booktitle = {Ocular Rigidity, Biomechanics and Hydrodynamics of the Eye}, editor = {Pallikaris, I. and Tsilimbaris, M. K. and Dastiridou, A. I.}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-64422-2}, doi = {10.1007/978-3-030-64422-2_2}, pages = {15 -- 43}, year = {2021}, abstract = {The term ocular rigidity is widely used in clinical ophthalmology. Generally it is assumed as a resistance of the whole eyeball to mechanical deformation and relates to biomechanical properties of the eye and its tissues. Basic principles and formulas for clinical tonometry, tonography and pulsatile ocular blood flow measurements are based on the concept of ocular rigidity. There is evidence for altered ocular rigidity in aging, in several eye diseases and after eye surgery. Unfortunately, there is no consensual view on ocular rigidity: it used to make a quite different sense for different people but still the same name. Foremost there is no clear consent between biomechanical engineers and ophthalmologists on the concept. Moreover ocular rigidity is occasionally characterized using various parameters with their different physical dimensions. In contrast to engineering approach, clinical approach to ocular rigidity claims to characterize the total mechanical response of the eyeball to its deformation without any detailed considerations on eye morphology or material properties of its tissues. Further to the previous chapter this section aims to describe clinical approach to ocular rigidity from the perspective of an engineer in an attempt to straighten out this concept, to show its advantages, disadvantages and various applications.}, language = {en} } @inproceedings{IomdinaKiselevaKotliaretal.2020, author = {Iomdina, Elena N. and Kiseleva, Anna A. and Kotliar, Konstantin and Luzhnov, Petr V.}, title = {Quantification of Choroidal Blood Flow Using the OCT-A System Based on Voxel Scan Processing}, series = {Proceedings of the International Conference on Biomedical Innovations and Applications- BIA 2020}, booktitle = {Proceedings of the International Conference on Biomedical Innovations and Applications- BIA 2020}, publisher = {IEEE}, address = {New York, NY}, isbn = {978-1-7281-7073-2}, doi = {10.1109/BIA50171.2020.9244511}, pages = {41 -- 44}, year = {2020}, abstract = {The paper presents a method for the quantitative assessment of choroidal blood flow using an OCT-A system. The developed technique for processing of OCT-A scans is divided into two stages. At the first stage, the identification of the boundaries in the selected portion was performed. At the second stage, each pixel mark on the selected layer was represented as a volume unit, a voxel, which characterizes the region of moving blood. Three geometric shapes were considered to represent the voxel. On the example of one OCT-A scan, this work presents a quantitative assessment of the blood flow index. A possible modification of two-stage algorithm based on voxel scan processing is presented.}, language = {en} } @article{WerfelGuenthnerHapfelmeieretal.2022, author = {Werfel, Stanislas and G{\"u}nthner, Roman and Hapfelmeier, Alexander and Hanssen, Henner and Kotliar, Konstantin and Heemann, Uwe and Schmaderer, Christoph}, title = {Identification of cardiovascular high-risk groups from dynamic retinal vessel signals using untargeted machine learning}, series = {Cardiovascular Research}, volume = {118}, journal = {Cardiovascular Research}, number = {2}, editor = {Guzik, Tomasz J.}, publisher = {Oxford University Press}, address = {Oxford}, issn = {0008-6363}, doi = {10.1093/cvr/cvab040}, pages = {612 -- 621}, year = {2022}, abstract = {Dynamic retinal vessel analysis (DVA) provides a non-invasive way to assess microvascular function in patients and potentially to improve predictions of individual cardiovascular (CV) risk. The aim of our study was to use untargeted machine learning on DVA in order to improve CV mortality prediction and identify corresponding response alterations.}, language = {en} } @article{MalanHamerKaeneletal.2020, author = {Malan, Leone and Hamer, Mark and K{\"a}nel, Roland von and Kotliar, Konstantin and Wyk, Roelof D. van and Lambert, Gavin W. and Vilser, Walthard and Ziemssen, Tjalf and Schlaich, Markus P. and Smith, Wayne and Magnusson, Martin and Wentzel, Annemarie and Myburgh, Carlien E. and Steyn, Hendrik S. and Malan, Nico T.}, title = {Delayed retinal vein recovery responses indicate both non-adaptation to stress as well as increased risk for stroke: the SABPA study}, series = {Cardiovascular Journal of Africa}, volume = {26}, journal = {Cardiovascular Journal of Africa}, number = {31}, publisher = {Clinics Cardive Publishing}, address = {Durbanville}, issn = {1680-0745}, doi = {10.5830/CVJA-2020-031}, pages = {1 -- 12}, year = {2020}, language = {en} } @article{StreeseKotliarDeiserothetal.2020, author = {Streese, Lukas and Kotliar, Konstantin and Deiseroth, Arne and Infanger, Denis and Gugleta, Konstantin and Schmaderer, Christoph and Hanssen, Henner}, title = {Retinal endothelial function in cardiovascular risk patients: A randomized controlled exercise trial}, series = {Scandinavian Journal of Medicine and Science in Sports}, volume = {30}, journal = {Scandinavian Journal of Medicine and Science in Sports}, number = {2}, publisher = {Wiley}, address = {Oxford}, issn = {1600-0838}, doi = {10.1111/sms.13560}, pages = {272 -- 280}, year = {2020}, abstract = {The aim of this study was to investigate, for the first time, the effects of high-intensity interval training (HIIT) on retinal microvascular endothelial function in cardiovascular (CV) risk patients. In the randomized controlled trial, middle-aged and previously sedentary patients with increased CV risk (aged 58 ± 6 years) with ≥ two CV risk factors were randomized into a 12-week HIIT (n = 33) or control group (CG, n = 36) with standard physical activity recommendations. A blinded examiner measured retinal endothelial function by flicker light-induced maximal arteriolar (ADmax) and venular (VDmax) dilatation as well as the area under the arteriolar (AFarea) and venular (VFarea) flicker curve using a retinal vessel analyzer. Standardized assessments of CV risk factors, cardiorespiratory fitness, and retinal endothelial function were performed before and after HIIT. HIIT reduced body mass index, fat mass, and low-density lipoprotein and increased muscle mass and peak oxygen uptake (VO2peak). Both ADmax (pre: 2.7 ± 2.1\%, post: 3.0 ± 2.2\%, P = .018) and AFarea (pre: 32.6 ± 28.4\%*s, post: 37.7 ± 30.6\%*s, P = .016) increased after HIIT compared with CG (ADmax, pre: 3.2 ± 1.8\%, post: 2.9 ± 1.8\%, P = .254; AFarea, pre: 41.6 ± 28.5\%*s, post: 37.8 ± 27.0\%*s, P = .186). Venular function remained unchanged after HIIT. There was a significant association between ∆-change VO2peak and ∆-changes ADmax and AFarea (P = .026, R² = 0.073; P = .019, R² = 0.081, respectively). 12-weeks of HIIT improved retinal endothelial function in middle-aged patients with increased CV risk independent of the reduction in classical CV risk factors. Exercise has the potential to reverse or at least postpone progression of small vessel disease in older adults with increased CV risk under standard medication. Dynamic retinal vessel analysis seems to be a sensitive tool to detect treatment effects of exercise interventions on retinal microvascular endothelial function in middle-aged individuals with increased CV risk.}, language = {en} } @article{HamouKotliarTanetal.2020, author = {Hamou, Hussam Aldin and Kotliar, Konstantin and Tan, Sonny Kian and Weiß, Christel and Blume, Christian and Clusmann, Hans and Schubert, Gerrit Alexander and Albanna, Walid}, title = {Surgical nuances and placement of subgaleal drains for supratentorial procedures—a prospective analysis of efficacy and outcome in 150 craniotomies}, series = {Acta Neurochirurgica}, volume = {2020}, journal = {Acta Neurochirurgica}, number = {162}, publisher = {Springer Nature}, address = {Cham}, issn = {0942-0940}, doi = {10.1007/s00701-019-04196-6}, pages = {729 -- 736}, year = {2020}, abstract = {Background For supratentorial craniotomy, surgical access, and closure technique, including placement of subgaleal drains, may vary considerably. The influence of surgical nuances on postoperative complications such as cerebrospinal fluid leakage or impaired wound healing overall remains largely unclear. With this study, we are reporting our experiences and the impact of our clinical routines on outcome in a prospectively collected data set. Method We prospectively observed 150 consecutive patients undergoing supratentorial craniotomy and recorded technical variables (type/length of incision, size of craniotomy, technique of dural and skin closure, type of dressing, and placement of subgaleal drains). Outcome variables (subgaleal hematoma/CSF collection, periorbital edema, impairment of wound healing, infection, and need for operative revision) were recorded at time of discharge and at late follow-up. Results Early subgaleal fluid collection was observed in 36.7\% (2.8\% at the late follow-up), and impaired wound healing was recorded in 3.3\% of all cases, with an overall need for operative revision of 6.7\%. Neither usage of dural sealants, lack of watertight dural closure, and presence of subgaleal drains, nor type of skin closure or dressing influenced outcome. Curved incisions, larger craniotomy, and tumor size, however, were associated with an increase in early CSF or hematoma collection (p < 0.0001, p = 0.001, p < 0.01 resp.), and larger craniotomy size was associated with longer persistence of subgaleal fluid collections (p < 0.05). Conclusions Based on our setting, individual surgical nuances such as the type of dural closure and the use of subgaleal drains resulted in a comparable complication rate and outcome. Subgaleal fluid collections were frequently observed after supratentorial procedures, irrespective of the closing technique employed, and resolve spontaneously in the majority of cases without significant sequelae. Our results are limited due to the observational nature in our single-center study and need to be validated by supportive prospective randomized design.}, language = {en} } @article{RamoshabaHuismanLammertynetal.2020, author = {Ramoshaba, Nthai E. and Huisman, Hugo W. and Lammertyn, Leandi and Kotliar, Konstantin and Schutte, Aletta E. and Smith, Wayne}, title = {Retinal microvasculature and masked hypertension in young adults: the African-PREDICT study}, series = {Hypertension Research}, journal = {Hypertension Research}, number = {43}, publisher = {Springer Nature}, address = {Osaka}, issn = {1348-4214}, doi = {10.1038/s41440-020-0487-0}, pages = {1231 -- 1238}, year = {2020}, abstract = {Masked hypertension is known to induce microvascular complications. However, it is unclear whether early microvascular changes are already occurring in young, otherwise healthy adults. We therefore investigated whether retinal microvascular calibers and acute responses to a flicker stimulus are related to masked hypertension. We used the baseline data of 889 participants aged 20-30 years who were taking part in the African Prospective study on the Early Detection and Identification of Cardiovascular Disease and Hypertension. Clinic and 24-h ambulatory blood pressure were measured. The central retinal artery equivalent (CRAE) and central retinal vein equivalent were calculated from fundus images, and retinal vessel dilation was determined in response to flicker light-induced provocation. A smaller CRAE was observed in those with masked hypertension vs. those with normotension (157.1 vs. 161.2 measuring units, P < 0.001). In forward multivariable-adjusted regression analysis, only CRAE was negatively related to masked hypertension [adjusted R² = 0.267, β = -0.097 (95\% CI = -0.165; -0.029), P = 0.005], but other retinal microvascular parameters were not associated with masked hypertension. In multivariable logistic regression analyses, masked hypertension [OR = 2.333, (95\% CI = 1.316; 4.241), P = 0.004] was associated with a narrower CRAE. In young healthy adults, masked hypertension was associated with retinal arteriolar narrowing, thereby reflecting early microvascular alterations known to predict cardiovascular outcomes in later life.}, language = {en} } @article{SmithKotliarLammertynetal.2020, author = {Smith, Wayne and Kotliar, Konstantin and Lammertyn, Leandi and Ramoshaba, Nthai E. and Vilser, Walthard and Huisman, Hugo W. and Schutte, Aletta E.}, title = {Retinal vessel caliber and caliber responses in true normotensive black and white adults: The African-PREDICT study}, series = {Microvascular Research}, volume = {128}, journal = {Microvascular Research}, number = {Article 103937}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0026-2862}, doi = {10.1016/j.mvr.2019.103937}, year = {2020}, abstract = {Purpose Globally, a detrimental shift in cardiovascular disease risk factors and a higher mortality level are reported in some black populations. The retinal microvasculature provides early insight into the pathogenesis of systemic vascular diseases, but it is unclear whether retinal vessel calibers and acute retinal vessel functional responses differ between young healthy black and white adults. Methods We included 112 black and 143 white healthy normotensive adults (20-30 years). Retinal vessel calibers (central retinal artery and vein equivalent (CRAE and CRVE)) were calculated from retinal images and vessel caliber responses to flicker light induced provocation (FLIP) were determined. Additionally, ambulatory blood pressure (BP), anthropometry and blood samples were collected. Results The groups displayed similar 24 h BP profiles and anthropometry (all p > .24). Black participants demonstrated a smaller CRAE (158 ± 11 vs. 164 ± 11 MU, p < .001) compared to the white group, whereas CRVE was similar (p = .57). In response to FLIP, artery maximal dilation was greater in the black vs. white group (5.6 ± 2.1 vs. 3.3 ± 1.8\%; p < .001). Conclusions Already at a young age, healthy black adults showed narrower retinal arteries relative to the white population. Follow-up studies are underway to show if this will be related to increased risk for hypertension development. The reason for the larger vessel dilation responses to FLIP in the black population is unclear and warrants further investigation.}, language = {en} } @article{FissabreRottke2023, author = {Fissabre, Anke and Rottke, Evelin}, title = {Das Quelle-Fertighaus : Einklang von Maß, Konstruktion und Entwurf}, series = {architectura}, volume = {51}, journal = {architectura}, number = {1}, editor = {Bergdoll, Barry and Schwarting, Andreas and Tragbar, Klaus}, publisher = {Deutscher Kunstverlag (DKV)}, address = {Berlin}, issn = {2569-1554}, doi = {10.1515/atc-2021-1005}, pages = {57 -- 78}, year = {2023}, abstract = {The steel prefabricated family house ›Quelle-Fertighaus‹ designed and constructed by the German company Quelle, is an innovative modular system commercialised in 1962. All aspects of the Quelle-Fertighaus are planned on the principle of minimal effort for maximal flexibility. The clever design of the ground plan based on a 4 m × 7 m module offers the flexibility for either one to three additional modules. The steel construction is innovative and unique, consisting of load-bearing portal frames acting as braces. The house design is furthermore characterised by a simple metrical grid layout and the practical placement of the foundation and basement, which allowed the very cost-effective production and the lowest price for a prefabricated family house in Germany during the postwar era. Nowadays its portal-frame-construction offers an interesting approach for its renovation and transformation according to present building demands.}, language = {de} } @article{NeumaierKotliarHaerenetal.2021, author = {Neumaier, Felix and Kotliar, Konstantin and Haeren, Roel Hubert Louis and Temel, Yasin and L{\"u}ke, Jan Niklas and Seyam, Osama and Lindauer, Ute and Clusmann, Hans and Hescheler, J{\"u}rgen and Schubert, Gerrit Alexander and Schneider, Toni and Albanna, Walid}, title = {Retinal Vessel Responses to Flicker Stimulation Are Impaired in Ca v 2.3-Deficient Mice—An in- vivo Evaluation Using Retinal Vessel Analysis (RVA)}, series = {Frontiers in Neurology}, volume = {12}, journal = {Frontiers in Neurology}, publisher = {Frontiers}, doi = {10.3389/fneur.2021.659890}, pages = {1 -- 11}, year = {2021}, language = {en} } @inproceedings{HauggKreyerKemperetal.2020, author = {Haugg, Albert Thomas and Kreyer, J{\"o}rg and Kemper, Hans and Hatesuer, Katerina and Esch, Thomas}, title = {Heat exchanger for ORC. adaptability and optimisation potentials}, series = {IIR International Rankine 2020 Conference}, booktitle = {IIR International Rankine 2020 Conference}, doi = {10.18462/iir.rankine.2020.1224}, pages = {10 Seiten}, year = {2020}, abstract = {The recovery of waste heat requires heat exchangers to extract it from a liquid or gaseous medium into another working medium, a refrigerant. In Organic Rankine Cycles (ORC) on Combustion Engines there are two major heat sources, the exhaust gas and the water/glycol fluid from the engine's cooling circuit. A heat exchanger design must be adapted to the different requirements and conditions resulting from the heat sources, fluids, system configurations, geometric restrictions, and etcetera. The Stacked Shell Cooler (SSC) is a new and very specific design of a plate heat exchanger, created by AKG, which allows with a maximum degree of freedom the optimization of heat exchange rate and the reduction of the related pressure drop. This optimization in heat exchanger design for ORC systems is even more important, because it reduces the energy consumption of the system and therefore maximizes the increase in overall efficiency of the engine.}, language = {en} } @incollection{AtmaneHirechKassmietal.2020, author = {Atmane, Ilias and Hirech, Kamal and Kassmi, K. and Mahdi, Zahra and Alexopoulos, Spiros and Schwarzer, Klemens and Chayeb, H. and Bachiri, N.}, title = {Design and realization of a pilot solar desalination plant in Douar El Hamri in the province of Berkane (Morocco)}, series = {Sustainable entrepreneurship, renewable energy-based projects, and digitalization}, booktitle = {Sustainable entrepreneurship, renewable energy-based projects, and digitalization}, editor = {Omrane, Amina and Kassmi, Khalil and Akram, Muhammad Wasim and Khanna, Ashish and Mostafiz, Imtiaz}, publisher = {CRC Press}, address = {Boca Raton, Fa.}, isbn = {9781000292541 (E-Book)}, pages = {18 Seiten}, year = {2020}, abstract = {Producing fresh water from saline water has become one of the most difficult challenges to overcome especially with the high demand and shortage of fresh water. In this context, as part of a collaboration with Germany, the authors propose a design and implementation of a pilot multi-stage solar desalination system (MSD), remotely controlled, at Douar Al Hamri in the rural town of Boughriba in the province of Berkane, Morocco. More specifically, they present their contribution on the remote control and supervision system, which makes the functioning of the MSD system reliable and guarantees the production of drinking water for the population of Douar. The results obtained show that the electronic cards and computer communication software implemented allow the acquisition of all electrical (currents, voltages, powers, yields), thermal (temperatures of each stage), and meteorological (irradiance and ambient temperature), remote control and maintenance (switching on, off, data transfer). By comparing with the literature carried out in the field of solar energy, the authors conclude that the MSD and electronic desalination systems realized during this work represent a contribution in terms of the reliability and durability of providing drinking water in rural and urban areas.}, language = {en} } @inproceedings{AlexopoulosBreitbachHoffschmidt2009, author = {Alexopoulos, Spiros and Breitbach, Gerd and Hoffschmidt, Bernhard}, title = {Optimization of the channel form geometry of porous ReSiC ceramic membrane modules}, series = {Proceedings / International Conference \& Exhibition for Filtration and Separation Technology, FILTECH 2009 : October 13 - 15, 2009, Wiesbaden, Germany. Vol. 2}, booktitle = {Proceedings / International Conference \& Exhibition for Filtration and Separation Technology, FILTECH 2009 : October 13 - 15, 2009, Wiesbaden, Germany. Vol. 2}, publisher = {Filtech Exhibitions Germany}, address = {Meerbusch}, isbn = {978-3-941655-36-2}, pages = {686 -- 693}, year = {2009}, language = {en} } @article{DegeringEggertPulsetal.2010, author = {Degering, Christian and Eggert, Thorsten and Puls, Michael and Bongaerts, Johannes and Evers, Stefan and Maurer, Karl-Heinz and Jaeger, Karl-Erich}, title = {Optimization of protease secretion in Bacillus subtilis and Bacillus licheniformis by screening of homologous and herologous signal peptides}, series = {Applied and environmental microbiology}, volume = {76}, journal = {Applied and environmental microbiology}, number = {19}, publisher = {American Society for Microbiology}, address = {Washington, DC}, issn = {1098-5336 (E-Journal); 0003-6919 (Print); 0099-2240 (Print)}, doi = {10.1128/AEM.01146-10}, pages = {6370 -- 6378}, year = {2010}, abstract = {Bacillus subtilis and Bacillus licheniformis are widely used for the large-scale industrial production of proteins. These strains can efficiently secrete proteins into the culture medium using the general secretion (Sec) pathway. A characteristic feature of all secreted proteins is their N-terminal signal peptides, which are recognized by the secretion machinery. Here, we have studied the production of an industrially important secreted protease, namely, subtilisin BPN′ from Bacillus amyloliquefaciens. One hundred seventy-three signal peptides originating from B. subtilis and 220 signal peptides from the B. licheniformis type strain were fused to this secretion target and expressed in B. subtilis, and the resulting library was analyzed by high-throughput screening for extracellular proteolytic activity. We have identified a number of signal peptides originating from both organisms which produced significantly increased yield of the secreted protease. Interestingly, we observed that levels of extracellular protease were improved not only in B. subtilis, which was used as the screening host, but also in two different B. licheniformis strains. To date, it is impossible to predict which signal peptide will result in better secretion and thus an improved yield of a given extracellular target protein. Our data show that screening a library consisting of homologous and heterologous signal peptides fused to a target protein can identify more-effective signal peptides, resulting in improved protein export not only in the original screening host but also in different production strains.}, language = {en} } @article{DeppeBongaertsO'Connelletal.2011, author = {Deppe, Veronika Maria and Bongaerts, Johannes and O'Connell, Timothy and Maurer, Karl-Heinz and Meinhardt, Friedhelm}, title = {Enzymatic deglycation of Amadori products in bacteria}, series = {Applied microbiology and biotechnology}, volume = {Vol. 90}, journal = {Applied microbiology and biotechnology}, number = {Iss. 2}, publisher = {Springer}, address = {Berlin}, issn = {1432-0614 (E-Journal); 0171-1741 (Print); 0175-7598 (Print); 0340-2118 (Print)}, pages = {399 -- 406}, year = {2011}, language = {en} } @inproceedings{IlleSchrammAdametal.2009, author = {Ille, Fabian and Schramm, S. and Adam, M. and Backes, K. and Anthrakidis, Anette and Faber, Christian}, title = {Kraft-W{\"a}rme-K{\"a}lte-Kopplung im Leistungsbereich in 10kW mit periodisch arbeitender Sorptionsmaschine}, series = {DKV-Tagungsbericht. 35,2,1. Deutsche K{\"a}lte-Klima-Tagung 2008 Ulm}, booktitle = {DKV-Tagungsbericht. 35,2,1. Deutsche K{\"a}lte-Klima-Tagung 2008 Ulm}, publisher = {Dt. K{\"a}lte- und Klimatechnischer Verein}, address = {Hannover}, isbn = {978-3-932715-44-0}, pages = {305 -- 320}, year = {2009}, language = {de} } @inproceedings{AhlbrinkAlexopoulosAnderssonetal.2009, author = {Ahlbrink, N. and Alexopoulos, Spiros and Andersson, J. and Belhomme, B. and Teixeira Boura, Cristiano Jos{\´e} and Gall, J. and Hirsch, T.}, title = {viCERP - the Virtual Institute of Central Receiver Power Plant}, series = {MATHMOD 2009 - 6th Vienna International Conference on Mathematical Modelling : February 11 - 13, 2009, Vienna, Austria. ARGESIM Report. No. 35}, booktitle = {MATHMOD 2009 - 6th Vienna International Conference on Mathematical Modelling : February 11 - 13, 2009, Vienna, Austria. ARGESIM Report. No. 35}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {978-3-901608-35-3}, year = {2009}, language = {en} } @article{AlexopoulosHoffschmidt2017, author = {Alexopoulos, Spiros and Hoffschmidt, Bernhard}, title = {Advances in solar tower technology}, series = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, volume = {6}, journal = {Wiley interdisciplinary reviews : Energy and Environment : WIREs}, number = {1}, publisher = {Wiley}, address = {Weinheim}, issn = {2041-840X}, doi = {10.1002/wene.217}, pages = {1 -- 19}, year = {2017}, language = {en} }