TY  - JOUR
A1  - Wert, Stefan
A1  - Iken, Heiko
A1  - Schöning, Michael Josef
A1  - Matysik, Frank-Michael
T1  - Development of a temperature‐pulse enhanced electrochemical glucose biosensor and characterization of its stability via scanning electrochemical microscopy
JF  - Electroanalysis
N2  - Glucose oxidase (GOx) is an enzyme frequently used in glucose biosensors. As increased temperatures can enhance the performance of electrochemical sensors, we investigated the impact of temperature pulses on GOx that was drop-coated on flattened Pt microwires. The wires were heated by an alternating current. The sensitivity towards glucose and the temperature stability of GOx was investigated by amperometry. An up to 22-fold increase of sensitivity was observed. Spatially resolved enzyme activity changes were investigated via scanning electrochemical microscopy. The application of short (<100 ms) heat pulses was associated with less thermal inactivation of the immobilized GOx than long-term heating.
Y1  - 2021
U6  - https://doi.org/10.1002/elan.202100089
SN  - 1521-4109
IS  - Early View
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Weemstra, Monique
A1  - Eilmann, Britta
A1  - Sass-Klaassen, Ute G. W.
A1  - Sterck, Frank J.
T1  - Summer droughts limit tree growth across 10 temperate species on a productive forest site
JF  - Forest Ecology and Management
Y1  - 2013
U6  - https://doi.org/doi:10.1016/j.foreco.2013.06.007
SN  - 0378-1127 (Print)
SN  - 1872-7042  (Online)
VL  - 2013
IS  - 306
SP  - 142
EP  - 149
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Weckesser, Matthias
A1  - Hufnagel, Andreas
A1  - Ziemons, Karl
A1  - Grießmeier, Martin
A1  - Sonnenberg, Frank
A1  - Hackländer, Thomas
A1  - Langen, Karl-J.
A1  - Holschbach, Markus
A1  - Elger, Christian E.
A1  - Müller-Gärtner, Hans-W.
T1  - Effect of partial volume correction on muscarinic cholinergic receptor imaging with single-photon emission tomography in patients with temporal lobe epilepsy
JF  - European Journal of Nuclear Medicine
N2  - Animal experiments and preliminary results in humans have indicated alterations of hippocampal muscarinic acetylcholine receptors (mAChR) in temporal lobe epilepsy. Patients with temporal lobe epilepsy often present with a reduction in hippocampal volume. The aim of this study was to investigate the influence of hippocampal atrophy on the quantification of mAChR with single photon emission tomography (SPET) in patients with temporal lobe epilepsy. Cerebral uptake of the muscarinic cholinergic antagonist [123I]4-iododexetimide (IDex) was investigated by SPET in patients suffering from temporal lobe epilepsy of unilateral (n=6) or predominantly unilateral (n=1) onset. Regions of interest were drawn on co-registered magnetic resonance images. Hippocampal volume was determined in these regions and was used to correct the SPET results for partial volume effects. A ratio of hippocampal IDex binding on the affected side to that on the unaffected side was used to detect changes in muscarinic cholinergic receptor density. Before partial volume correction a decrease in hippocampal IDex binding on the focus side was found in each patient. After partial volume no convincing differences remained. Our results indicate that the reduction in hippocampal IDex binding in patients with epilepsy is due to a decrease in hippocampal volume rather than to a decrease in receptor concentration.
Y1  - 1997
SN  - 1619-7089
VL  - 24
IS  - 9
SP  - 1156
EP  - 1161
ER  - 
TY  - JOUR
A1  - Weckesser, Martin
A1  - Grießmeier, Martin
A1  - Schmidt, Daniela
A1  - Sonnenberg, Frank
A1  - Ziemons, Karl
A1  - Kemna, Lars
A1  - Holschbach, Marcus
A1  - Langen, Karl-J.
A1  - Müller-Gärtner, Hans-W.
T1  - Iodine-123 α-methyl tyrosine single-photon emission tomography of cerebral gliomas: standardised evaluation of tumour uptake and extent
JF  - European Journal of Nuclear Medicine
N2  - Single-photon emission tomography (SPET) with the amino acid analogue l-3-[123I]iodo-α-methyl tyrosine (IMT) is helpful in the diagnosis and monitoring of cerebral gliomas. Radiolabelled amino acids seem to reflect tumour infiltration more specifically than conventional methods like magnetic resonance imaging and computed tomography. Automatic tumour delineation based on maximal tumour uptake may cause an overestimation of mean tumour uptake and an underestimation of tumour extension in tumours with circumscribed peaks. The aim of this study was to develop a program for tumour delineation and calculation of mean tumour uptake which takes into account the mean background activity and is thus optimised to the problem of tumour definition in IMT SPET. Using the frequency distribution of pixel intensities of the tomograms a program was developed which automatically detects a reference brain region and draws an isocontour region around the tumour taking into account mean brain radioactivity. Tumour area and tumour/brain ratios were calculated. A three-compartment phantom was simulated to test the program. The program was applied to IMT SPET studies of 20 patients with cerebral gliomas and was compared to the results of manual analysis by three different investigators. Activity ratios and chamber extension of the phantom were correctly calculated by the automatic analysis. A method based on image maxima alone failed to determine chamber extension correctly. Manual region of interest analysis in patient studies resulted in a mean inter-observer standard deviation of 8.7%±6.1% (range 2.7%–25.0%). The mean value of the results of the manual analysis showed a significant correlation to the results of the automatic analysis (r = 0.91, P<0.0001 for the uptake ratio; r = 0.87, P<0.0001 for the tumour area). We conclude that the algorithm proposed simplifies the calculation of uptake ratios and may be used for observer-independent evaluation of IMT SPET studies. Three-dimensional tumour recognition and transfer to co-registered morphological images based on this program may be useful for the planning of surgical and radiation treatment.
Y1  - 1998
SN  - 1619-7089
VL  - 25
IS  - 2
SP  - 150
EP  - 156
ER  - 
TY  - CHAP
A1  - Waldmann, Christoph
A1  - Vera, Jean-Pierre de
A1  - Dachwald, Bernd
A1  - Strasdeit, Henry
A1  - Sohl, Frank
A1  - Hanff, Hendrik
A1  - Kowalski, Julia
A1  - Heinen, Dirk
A1  - Macht, Sabine
A1  - Bestmann, Ulf
A1  - Meckel, Sebastian
A1  - Hildebrandt, Marc
A1  - Funke, Oliver
A1  - Gehrt, Jan-Jöran
T1  - Search for life in ice-covered oceans and lakes beyond Earth
T2  - 2018 IEEE/OES Autonomous Underwater Vehicle Workshop, Proceedings November 2018, Article number 8729761
N2  - The quest for life on other planets is closely connected with the search for water in liquid state. Recent discoveries of deep oceans on icy moons like Europa and Enceladus have spurred an intensive discussion about how these waters can be accessed. The challenge of this endeavor lies in the unforeseeable requirements on instrumental characteristics both with respect to the scientific and technical methods. The TRIPLE/nanoAUV initiative is aiming at developing a mission concept for exploring exo-oceans and demonstrating the achievements in an earth-analogue context, exploring the ocean under the ice shield of Antarctica and lakes like Dome-C on the Antarctic continent.
KW  - Planetary exploration
KW  - Jupiter
KW  - ice moons
KW  - underwater vehicle
KW  - Antarctica
Y1  - 2018
U6  - https://doi.org/10.1109/AUV.2018.8729761
ER  - 
TY  - BOOK
A1  - Thielemann, Frank
A1  - Staudt, Erich
A1  - Kriegesmann, Bernd
T1  - Joint-ventures. Staudt, Erich; Kriegesmann, Bernd; Thielemann, Frank
Y1  - 1994
N1  - Berichte aus der angewandten Innovationsforschung ; 133
PB  - Inst. für Angewandte Innovationsforschung e.V.
CY  - Bochum
ER  - 
TY  - JOUR
A1  - Thielemann, Frank
A1  - Bock, Jürgen
T1  - Organization and management of German-Russian joint ventures. Bock, Jürgen; Thielemann, Frank
JF  - International journal of technology management. 9 (1994), H. 8
Y1  - 1994
SN  - 0267-5730
SP  - 864
EP  - 879
ER  - 
TY  - CHAP
A1  - Späte, Frank
A1  - Hafner, B.
A1  - Schwarzer, Klemens
T1  - A system for solar process heat for decentralized applications in developing countries
T2  - ISES 1999 Solar World Congress, Jerusalem, Israel, July 4-9, 1999 : conference proceedings / ed. Gershon Grossman. Vol. 3
Y1  - 2000
SN  - 0-080-043895-4
SP  - 236
EP  - 291
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Späte, Frank
A1  - Faber, Christian
A1  - Schwarzer, Klemens
A1  - Hartz, Thomas
T1  - Comparison of solar hot water systems in solar settlements - decentralized or centralized systems?
JF  - Proceedings / organised by: ISES Europe ... [Ed.: Deutsche Gesellschaft für Sonnenenergie e.V. - DGS, Munich ; PSE GmbH - Forschung Entwicklung Marketing, Freiburg]. - Vol. 1
Y1  - 2004
SN  - 3-9809656-1-9
N1  - EuroSun <5, 2004, Freiburg, Breisgau> ; Internationales Sonnenforum <14, 2004, Freiburg, Breisgau> ; Deutsche Gesellschaft für Sonnenenergie
SP  - 1-666-1-671
PB  - PSE
CY  - Freiburg [Breisgau]
ER  - 
TY  - JOUR
A1  - Slabu, Ioana
A1  - Roeth, Anjali A.
A1  - Engelmann, Ulrich M.
A1  - Wiekhorst, Frank
A1  - Buhl, Eva M.
A1  - Neumann, Ulf P.
A1  - Schmitz-Rode, Thomas
T1  - Modeling of magnetoliposome uptake in human pancreatic tumor cells in vitro
JF  - Nanotechnology
Y1  - 2019
U6  - https://doi.org/10.1088/1361-6528/ab033e
SN  - 1361-6528
VL  - 30
IS  - 18
SP  - 184004
ER  -