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Harmful effects of electromagnetic fields (EMF) on cognitive and behavioural features of humans and rodents have been controversially discussed and raised persistent concern about adverse effects of EMF on general brain functions. In the present study we applied radio-frequency (RF) signals of the Universal Mobile Telecommunications System (UMTS) to full brain exposed male Wistar rats in order to elaborate putative influences on stress hormone release (corticosteron; CORT and adrenocorticotropic hormone; ACTH) and on hippocampal derived synaptic long-term plasticity (LTP) and depression (LTD) as electrophysiological hallmarks for memory storage and memory consolidation. Exposure was computer controlled providing blind conditions. Nominal brain-averaged specific absorption rates (SAR) as a measure of applied mass-related dissipated RF power were 0, 2, and 10 W/kg over a period of 120 min. Comparison of cage exposed animals revealed, regardless of EMF exposure, significantly increased CORT and ACTH levels which corresponded with generally decreased field potential slopes and amplitudes in hippocampal LTP and LTD. Animals following SAR exposure of 2 W/kg (averaged over the whole brain of 2.3 g tissue mass) did not differ from the sham-exposed group in LTP and LTD experiments. In contrast, a significant reduction in LTP and LTD was observed at the high power rate of SAR (10 W/kg). The results demonstrate that a rate of 2 W/kg displays no adverse impact on LTP and LTD, while 10 W/kg leads to significant effects on the electrophysiological parameters, which can be clearly distinguished from the stress derived background. Our findings suggest that UMTS exposure with SAR in the range of 2 W/kg is not harmful to critical markers for memory storage and memory consolidation, however, an influence of UMTS at high energy absorption rates (10 W/kg) cannot be excluded.
Plant physiology and plant stress: Plant physiology will be much more important for human mankind because of yield and cultivation limits of crops determined by their resistance to stress. To assess and counteract various stress factors it is necessary to conduct plant research to gain information and results on plant physiology.
Beim Ausbau nachhaltiger, regenerativer Energieversorgung hat die Umwandlung von organischer Biomasse in Biogas ein großes Potential. Der zugrundeliegende, komplexe biologische Prozess wird noch immer unzureichend verstanden und bedarf systematischer Untersuchungen der Prozessparameter, um einen hohen Ertrag bei guter Gasqualität zu ermöglichen. Die Fragestellungen zur Entschlüsselung des Prozesses sind sowohl verfahrenstechnischer als auch mikrobiologischer Natur. Aus mikrobiologischer Sicht ist die Kenntnis der tatsächlich beteiligten prozesstragenden Mikroorganismen von erheblicher Bedeutung, aus verfahrenstechnischer Sicht die Kenntnis der physikalischen und chemischen Faktoren, welche die mikrobiologischen Prozesse und kontrollieren. Im Zusammenspiel aller dieser Parameter wird die Biogasbildung befördert oder behindert, bis zum Abbruch des Prozesses.
Eine mögliche Kontrollmethode ist die Messung der metabolischen Aktivität prozesstragender Organismen.
Diese soll, beruhend auf fundierten Prozessdaten, gewonnen durch eine Parallelanlage, mit einem lichtadressierbaren potentiometrischen Sensor-System (LAPS) realisiert werden. Dieser Sensor ist in der Lage, pH-Wert-änderungen zu detektieren, die durch den Stoffwechsel der auf dem Chip immobilisierten Organismen hervorgerufen werden, um eine Online-Überwachung von Biogasanlagen zu ermöglichen.
Grass silage provides a great potential as renewable feedstock. Two fractions of the grass silage, a press juice and the fiber fraction, were evaluated for their possible use for bioethanol production. Direct production of ethanol from press juice is not possible due to high concentrations of organic acids. For the fiber fraction, alkaline peroxide or enzymatic pretreatment was used, which removes the phenolic acids in the cell wall. In this study, we demonstrate the possibility to integrate the enzymatic pretreatment with a simultaneous saccharification and fermentation to achieve ethanol production from grass silage in a one-process step. Achieved yields were about 53 g ethanol per kg silage with the alkaline peroxide pretreatment and 91 g/kg with the enzymatic pretreatment at concentrations of 8.5 and 14.6 g/L, respectively. Furthermore, it was shown that additional supplementation of the fermentation medium with vitamins, trace elements and nutrient salts is not necessary when the press juice is directly used in the fermentation step.
The magnetic forces of fringe magnetic fields of MR systems on ferromagnetic components can impose a severe patient, occupational health and safety hazard. MRI accidents are listed as number 9 of the top 10 risks in modern medicine. With the advent of ultrahigh field MR systems including passively shielded magnet versions, this risk, commonly known as the missile or projectile effect is even more pronounced. A strategy employing magnetic field sensors which can be attached to ferromagnetic objects that are commonly used in a clinical environment is conceptually appealing for the pursuit of reducing the risk of ferromagnetic projectile accidents.
Summary: This paper presents a methodology to study and understand the mechanics of stapled anastomotic behaviors by combining empirical experimentation and finite element analysis. Performance of stapled anastomosis is studied in terms of leakage and numerical results which are compared to in vitro experiments performed on fresh porcine tissue. Results suggest that leaks occur between the tissue and staple legs penetrating through the tissue.
A light-addressable potentiometric sensor (LAPS) can measure the concentration of one or several analytes at the sensor surface simultaneously in a spatially resolved manner. A modulated light pointer stimulates the semiconductor structure at the area of interest and a responding photocurrent can be read out. By simultaneous stimulation of several areas with light pointers of different modulation frequencies, the read out can be performed at the same time. With the new proposed controller electronic based on a field-programmable gate array (FPGA), it is possible to control the modulation frequencies, phase shifts, and light brightness of multiple light pointers independently and simultaneously. Thus, it is possible to investigate the frequency response of the sensor, and to examine the analyte concentration by the determination of the surface potential with the help of current/voltage curves and phase/voltage curves. Additionally, the ability to individually change the light intensities of each light pointer is used to perform signal correction.
Flight times to the heliopause using a combination of solar and radioisotope electric propulsion
(2011)
We investigate the interplanetary flight of a low-thrust space probe to the heliopause,located at a distance of about 200 AU from the Sun. Our goal was to reach this distance within the 25 years postulated by ESA for such a mission (which is less ambitious than the 15-year goal set by NASA). Contrary to solar sail concepts and combinations of allistic and electrically propelled flight legs, we have investigated whether the set flight time limit could also be kept with a combination of solar-electric propulsion and a second, RTG-powered upper stage. The used ion engine type was the RIT-22 for the first stage and the RIT-10 for the second stage. Trajectory optimization was carried out with the low-thrust optimization program InTrance, which implements the method of Evolutionary Neurocontrol,using Artificial Neural Networks for spacecraft steering and Evolutionary Algorithms to optimize the Neural Networks’ parameter set. Based on a parameter space study, in which the number of thrust units, the unit’s specific impulse, and the relative size of the solar power generator were varied, we have chosen one configuration as reference. The transfer time of this reference configuration was 29.6 years and the fastest one, which is technically
more challenging, still required 28.3 years. As all flight times of this parameter study were longer than 25 years, we further shortened the transfer time by applying a launcher-provided hyperbolic excess energy up to 49 km2/s2. The resulting minimal flight time for the reference configuration was then 27.8 years. The following, more precise optimization to a launch with the European Ariane 5 ECA rocket reduced the transfer time to 27.5 years. This is the fastest mission design of our study that is flexible enough to allow a launch every
year. The inclusion of a fly-by at Jupiter finally resulted in a flight time of 23.8 years,which is below the set transfer-time limit. However, compared to the 27.5-year transfer,this mission design has a significantly reduced launch window and mission flexibility if the
escape direction is restricted to the heliosphere’s “nose".
Forschungsbericht 2011
(2011)
Forschungsbericht / Themenheft : Life Sciences 4 Grußwort Prorektorin Prof. Dr. rer. nat. Christiane Vaeßen 6 Highlightprojekte 9 Nano- und Biotechnologien, Medizintechnik, Bioengineering 10 Institut für Nano- und Biotechnologien 11 Multifunktionaler Bio-Sensorchip für biodegradierbare Biopolymere 12 Intelligente Logik-Gatter mit stimuli-responsiven Hydrogelen 13 Entwicklung eines Multisensorsystems in Siliziumtechnik zur Berurteilung der Gärbiologie eines Anaerobfermenters in der Flüssigphase 14 Optimierung des Betriebs eines Biogasfermenters mithilfe eines Feldeffekt-Biosensors auf der Basis eines lichtadressierbaren potenziometrischen Sensors (Bio-LAPS) 15 Modulares Sensorsystem für die Zellkultur-Prozessentwicklung (Cellsens) 16 "Nano-inspirierte Oberflächen für die Entwicklung spezifischer Feldeffekt-Biosensoren 17 Multimodale Sensoren für die Umweltanalytik in flüssigen Medien im industriellen Umfeld 18 Gassensorik für den qualitativen und quantitativen Nachweis von H2O2 für aseptische Verpackungen im Bereich der Lebensmitteltechnologie 19 „Entwicklung von therapeutischen Impfstoffen gegen Krebs“ 20 Institut für Bioengineering 22 Zellbiophysik : Personalisierte Medizin - Wirkstoffanpassung mit CardiaKytos 23 Labor für Biomaterialien : Biokompatibilität von Werkstoffen bludruchströmter Medizingeräte 24 Labor für Zell- und Mikrobiologie : Zusammenschluss von Molekularer Biophysik und Mikrobiologie 25 Labor für Biomechanik : Virtuelle Realität: Geglättete Finite-Elemente –Methode zur Simulation in der Medizintechnik 26Labor für Biomechanik : Optimierung chirurgischer Klammernahtgeräte zur operativen Darm-Anastomose 27 Labor für Medizinische & Molekulare Biologie : CARA - Entwicklung einer nichtinvasiven Sonde für den klinischen Einsatz zur Prognose des Risikos einer Frühgeburt bei Schwangeren 30 Kompetenzplattform Bioengineering 31 IceMole eine sich autonom ins Eis grabende Sonde für die Polarforschung und die Suche nach Leben im Sonnensystem 33 Nahinfrarotspektroskopie zur Überwachung von Biogasanlagen 34 Schlingensysteme zur Behandlung von Belasungsinkontinenz 36 Weitere Forschungsaktivitäten Telemedizin : Produktstudien 39 Angewandte Polymerchemie, Nuklearchemie, Umweltbiotechnologie 40 Institut für angewandte Polymerchemie (IAP) : "Intelligente Hydrogele" als kontaktfrei steuerbare Pharmadepots zur gezielten Tumorbekämpfung 43 Das Labor für Nuklearchemie 45 Institut NOWUM -Energy 46 EnergieEffizienz-Netzwerk : Eine Chance für die Life-Science-Industrie 48 MiProBa : Ein Projekt zum Thema Biogas 49 Weitere Forschungsaktivitäten : IMMOTHERM 50 Systematische Untersuchung des Biogas-Prozesses : Beteiligte Mikroorganismen und deren Stoffwechsel 51 Der pflanzliche Aromatenstoffwechsel : Aller guten Dinge sind drei? Aromatenstoffwechsel 51 54 Impressum
ECG is corrupted by magneto-hydrodynamic effects at higher magnetic field strength. Artifacts in the ECG trace and severe T-wave elevation might be mis-interpreted as R-waves. MHD being inherently sensitive to blood flow and blood velocity provides an alternative approach for cardiac gating, even in peripheral target areas far away from the commonly used upper torso positions of ECG electrodes. This feature would be very beneficial to address traveling time induced motion artifacts and trigger latency related issues raised by ECG-gated peripheral MR angiography. For all those reasons, this work proposes the use of MHD-trigger for cardiac gated MR.
Future evolution of risk management for structures : Advancement for the future IEC 62305-2 Ed3
(2011)
Durch die Fragmentierung von Wertschöpfungsketten ergeben sich neue Herausforderungen für das Management von Kundenbeziehungen. Die Dissertation untersucht die daraus resultierenden Anforderungen an eine übergreifende Integration von Customer Relationship Management in der
Telekommunikationsindustrie. Ziel ist es, durch Anwendung von Methoden eines Enterprise Architecture Framework eine übergreifend Lösung zu gestalten. Grundlegende Prämisse dabei ist, dass die übergreifende Gestaltung eines Customer Relationship Management für alle an der
Wertschöpfung beteiligten Unternehmen vorteilhaft ist.
HisT/PLIER : A Two-Fold Provenance Approach for Grid-Enabled Scientific Workflows Using WS-VLAM
(2011)
Hybride Produktionssysteme
(2011)
Während die virtuelle Produktentstehungskette große Gestaltungsfreiräume bietet, ist die reale Produktentstehungskette durch wesentlich mehr Randbedingungen gekennzeichnet, die nicht oder nur ansatzweise beeinflussbar sind. Die Realisierung des aus logistischer Sicht optimalen One-Piece-Flow bei gleichzeitiger Steigerung von Flexibilität und Produktivität sowie des Verschiebens der Grenze des technologisch Machbaren müssen in zukünftigen Forschungsansätzen gleichermaßen betrachtet werden. Die Grenzverschiebung auf Basis der Integration von Technologien ist dabei ein viel versprechender Ansatz, der es in vielen Fällen ermöglicht, in allen genannten Zielrichtungen gleichermaßen Potentiale zu erschließen.
Hydrostatic propeller drive
(2011)
We present the novel concept of a combined drilling and melting probe for subsurface ice research. This probe, named “IceMole”, is currently developed, built, and tested at the FH Aachen University of Applied Sciences’ Astronautical Laboratory. Here, we describe its first prototype design and report the results of its field tests on the Swiss Morteratsch glacier. Although the IceMole design is currently adapted to terrestrial glaciers and ice shields, it may later be modified for the subsurface in-situ investigation of extraterrestrial ice, e.g., on Mars, Europa, and Enceladus. If life exists on those bodies, it may be present in the ice (as life can also be found in the deep ice of Earth).
Im Reich der Sinne
(2011)
In den ersten Lebensjahren lernen Kinder ihre Umgebung wahrzunehmen. Dabei kann die Entwicklung von Geschicklichkeit, Feinmotorik und Kommunikation durch Spielsachen gezielt gefördert werden. Daher richtet sich diese Bachelorarbeit an die Erlebniswelt der Kinder. JELLE bietet als modulares Sitz- und Erlebnismöbel eine große Vielfalt sowohl aktiver als auch fantasievoller Spielszenarien und setzt durch den Aufforderungscharakter neue Spielimpulse, die zum weiterspielen anregen. Das kompakte und gruppierbare Basismodul von JELLE kann durch viel Zubehör an die Bedürfnisse unterschiedlicher Altersgruppen angepasst werden, um Kinder erlebnisreich und pädagogisch anspruchsvoll zu fördern.
Kompakter Aufbau eines lichtadressierbaren potentiometrischen Sensors mit verfahrbarem Diodenlaser
(2011)
Lagerstabiles flüssiges Wasch- oder Reinigungsmittel enthaltend Proteasen [Offenlegungsschrift]
(2011)
Lignocellulosic biorefinery: Process integration of hydrolysis and fermentation (SSF process)
(2011)
The aim of the present work is the process integration and the optimization of the enzymatic hydrolysis of wood and the following fermentation of the products to ethanol. The substrate is a fiber fraction obtained by organosolv pre-treatment of beech wood. For the ethanol production, a co-fermentation by two different yeasts (Saccharomyces cerevisiae and Pachysolen tannophilus) was carried out to convert glucose as well as xylose. Two approaches has been followed: 1. A two step process, in which the hydrolysis of the fiber fraction and the fermentation to product are separated from each other. 2. A process, in which the hydrolysis and the fermentation are carried out in one single process step as simultaneous saccharification and fermentation (SSF). Following the first approach, a yield of about 0.15 g ethanol per gram substrate can be reached. Based on the SSF, one process step can be saved, and additionally, the gained yield can be raised up to 0.3 g ethanol per gram substrate.
The purpose of this study was to investigate whether sprint performance is related to lower leg musculoskeletal geometry within a homogeneous group of highly trained 100-m sprinters. Using a cluster analysis, eighteen male sprinters were divided into two groups based on their personal best (fast: N = 11, 10.30 ± 0.07 s; slow: N = 7, 10.70 ± 0.08 s). Calf muscular fascicle arrangement and Achilles tendon moment arms (calculated by the gradient of tendon excursion versus ankle joint angle) were analyzed for each athlete using ultrasonography. Achilles tendon moment arm, foot and ankle skeletal geometry, fascicle arrangement as well as the ratio of fascicle length to Achilles tendon moment arm showed no significant (p > 0.05) correlation with sprint performance, nor were there any differences in the analyzed musculoskeletal parameters between the fast and slow sprinter group. Our findings provide evidence that differences in sprint ability in world-class athletes are not a result of differences in the geometrical design of the lower leg even when considering both skeletal and muscular components.
Durch die Kombination von Oligonukleotid-Liganden (Aptameren) hoher Bindungsaffinitäten
mit hochselektiv abtrennbaren magnetisierbaren Mikropartikeln
wird eine einstufige Separation von Zielmolekülen aus mikrobiologischen
Produktionsansätzen möglich. Die Aptamere werden hierfür reversibel
auf den Partikeloberflächen gebunden und für die spezifische Isolierung von
Bioprodukten eingesetzt. Die Abtrennung der beladenen Partikel erfolgt
durch einen neuen Rotor-Stator-Separator mit Hochgradient-Magnetfeld.
Market changes have forced telecommunication companies to transform their business. Increased competition, short innovation cycles, changed usage patterns, increased customer expectations and cost reduction are the main drivers. Our objective is to analyze to what extend transformation projects have improved the orientation towards the end-customers. Therefore, we selected 38 real-life case studies that are dealing with customer orientation. Our analysis is based on a telecommunication-specific framework that aligns strategy, business processes and information systems. The result of our analysis shows the following: transformation projects that aim to improve the customer orientation are combined with clear goals on costs and revenue of the enterprise. These projects are usually directly linked to the customer touch points, but also to the development and provisioning of products. Furthermore, the analysis shows that customer orientation is not the sole trigger for transformation. There is no one-fits-all solution; rather, improved customer orientation needs aligned changes of business processes as well as information systems related to different parts of the company.
Meiotic functions of RAD18
(2011)
Der Erfolg eines Softwarenentwicklungsprojektes insbesondere eines Systemintegrationsprojektes wird mit der Erfüllung des „Teufelsdreiecks“, „In-Time“, „In-Budget“, „In-Quality“ gemessen. Hierzu ist die Kenntnis der Software- und Prozessqualität essenziell, um die Einhaltung der Qualitätskriterien festzustellen, aber auch, um eine Vorhersage hinsichtlich Termin- und Budgettreue zu treffen. Zu diesem Zweck wurde in der T-Systems Systems Integration ein System aus verschiedenen Key Performance Indikatoren entworfen und in der Organisation implementiert, das genau das leistet und die Kriterien für CMMI Level 3 erfüllt.