@misc{SchaeferLoefflerKleinetal.2021, author = {Schaefer, Laura and L{\"o}ffler, Nils and Klein, Julia and Bittmann, Frank}, title = {Mechanomyography and acceleration show interlimb asymmetries in Parkinson patients without tremor compared to controls during a unilateral motor task}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, issn = {1866-8364}, doi = {10.25932/publishup-52304}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-523049}, pages = {17}, year = {2021}, abstract = {The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson's disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70\% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.}, language = {en} } @article{SchaeferLoefflerKleinetal.2021, author = {Schaefer, Laura and L{\"o}ffler, Nils and Klein, Julia and Bittmann, Frank}, title = {Mechanomyography and acceleration show interlimb asymmetries in Parkinson patients without tremor compared to controls during a unilateral motor task}, series = {Scientific Reports}, volume = {11}, journal = {Scientific Reports}, publisher = {Springer Nature}, address = {Berlin}, issn = {2045-2322}, doi = {10.1038/s41598-021-81672-z}, pages = {15}, year = {2021}, abstract = {The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson's disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70\% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p = 0.001, r = 0.43) and for the amplitude variation (p = 0.003, r = 0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p = 0.013, r = 0.42) and MMGbra (p = 0.048, r = 0.39) as well as regarding the mean frequency (p = 0.004, r = 0.48) and amplitude variation of MMGpect (p = 0.033, r = 0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p = 0.022, r = 0.33; CV: p = 0.004, r = 0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.}, language = {en} } @article{SchaeferLoefflerKleinetal.2021, author = {Schaefer, Laura and L{\"o}ffler, Nils and Klein, Julia and Bittmann, Frank}, title = {Mechanomyography and acceleration show interlimb asymmetries in Parkinson patients without tremor compared to controls during a unilateral motor task}, series = {Scientific reports}, volume = {11}, journal = {Scientific reports}, number = {1}, publisher = {Macmillan}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-021-81672-z}, pages = {15}, year = {2021}, abstract = {The mechanical muscular oscillations are rarely the objective of investigations regarding the identification of a biomarker for Parkinson's disease (PD). Therefore, the aim of this study was to investigate whether or not this specific motor output differs between PD patients and controls. The novelty is that patients without tremor are investigated performing a unilateral isometric motor task. The force of armflexors and the forearm acceleration (ACC) were recorded as well as the mechanomyography of the biceps brachii (MMGbi), brachioradialis (MMGbra) and pectoralis major (MMGpect) muscles using a piezoelectric-sensor-based system during a unilateral motor task at 70\% of the MVIC. The frequency, a power-frequency-ratio, the amplitude variation, the slope of amplitudes and their interlimb asymmetries were analysed. The results indicate that the oscillatory behavior of muscular output in PD without tremor deviates from controls in some parameters: Significant differences appeared for the power-frequency-ratio (p=0.001, r=0.43) and for the amplitude variation (p=0.003, r=0.34) of MMGpect. The interlimb asymmetries differed significantly concerning the power-frequency-ratio of MMGbi (p=0.013, r=0.42) and MMGbra (p=0.048, r=0.39) as well as regarding the mean frequency (p=0.004, r=0.48) and amplitude variation of MMGpect (p=0.033, r=0.37). The mean (M) and variation coefficient (CV) of slope of ACC differed significantly (M: p=0.022, r=0.33; CV: p=0.004, r=0.43). All other parameters showed no significant differences between PD and controls. It remains open, if this altered mechanical muscular output is reproducible and specific for PD.}, language = {en} } @phdthesis{Loeffler2005, author = {L{\"o}ffler, Frank}, title = {Numerical simulations of neutron star - black hole mergers}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-7743}, school = {Universit{\"a}t Potsdam}, year = {2005}, abstract = {Collisions of black holes and neutron stars, named mixed binaries in the following, are interesting because of at least two reasons. Firstly, it is expected that they emit a large amount of energy as gravitational waves, which could be measured by new detectors. The form of those waves is expected to carry information about the internal structure of such systems. Secondly, collisions of such objects are the prime suspects of short gamma ray bursts. The exact mechanism for the energy emission is unknown so far. In the past, Newtonian theory of gravitation and modifications to it were often used for numerical simulations of collisions of mixed binary systems. However, near to such objects, the gravitational forces are so strong, that the use of General Relativity is necessary for accurate predictions. There are a lot of problems in general relativistic simulations. However, systems of two neutron stars and systems of two black holes have been studies extensively in the past and a lot of those problems have been solved. One of the remaining problems so far has been the use of hydrodynamic on excision boundaries. Inside excision regions, no evolution is carried out. Such regions are often used inside black holes to circumvent instabilities of the numerical methods near the singularity. Methods to handle hydrodynamics at such boundaries have been described and tests are shown in this work. One important test and the first application of those methods has been the simulation of a collapsing neutron star to a black hole. The success of these simulations and in particular the performance of the excision methods was an important step towards simulations of mixed binaries. Initial data are necessary for every numerical simulation. However, the creation of such initial data for general relativistic situations is in general very complicated. In this work it is shown how to obtain initial data for mixed binary systems using an already existing method for initial data of two black holes. These initial data have been used for evolutions of such systems and problems encountered are discussed in this work. One of the problems are instabilities due to different methods, which could be solved by dissipation of appropriate strength. Another problem is the expected drift of the black hole towards the neutron star. It is shown, that this can be solved by using special gauge conditions, which prevent the black hole from moving on the computational grid. The methods and simulations shown in this work are only the starting step for a much more detailed study of mixed binary system. Better methods, models and simulations with higher resolution and even better gauge conditions will be focus of future work. It is expected that such detailed studies can give information about the emitted gravitational waves, which is important in view of the newly built gravitational wave detectors. In addition, these simulations could give insight into the processes responsible for short gamma ray bursts.}, subject = {Relativistische Astrophysik}, language = {en} } @book{BauerHajaschLuebkingetal.2017, author = {Bauer, Hartmut and Hajasch, Lydia and L{\"u}bking, Uwe and Stein, Ursula and Roth, Roland and Sippel, Hanns-J{\"o}rg and Bock, Stephanie and Friesecke, Frank and Kleger, Heinz and Vowe, Gerhard and Utz, Stephanie Sophia and Buchmann, Madeleine and L{\"o}ffler, Roland and Zielske, Johanna}, title = {Partizipation in der B{\"u}rgerkommune}, series = {KWI Schriften}, journal = {KWI Schriften}, number = {10}, editor = {Bauer, Hartmut and B{\"u}chner, Christiane and Hajasch, Lydia}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, isbn = {978-3-86956-371-8}, issn = {1867-951X}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-101601}, publisher = {Universit{\"a}t Potsdam}, pages = {214}, year = {2017}, abstract = {Konzepte, nach denen sich die demokratische Mitwirkung der B{\"u}rger vornehmlich in Wahlen ersch{\"o}pft, geh{\"o}ren sp{\"a}testens seit „Stuttgart 21" der Vergangenheit an. Indes ist die B{\"u}rgerbeteiligung auch jenseits solcher Großprojekte l{\"a}ngst zu einem beherrschenden Thema der Zeit herangewachsen. Das gilt zumal f{\"u}r die kommunale Ebene. Dort werden traditionsreiche Partizipationsformen nicht nur intensiv genutzt, sondern zunehmend um neue Beteiligungsvarianten erg{\"a}nzt und in innovativen Modellprojekten fortentwickelt. Dabei treten zwei Antriebskr{\"a}fte besonders hervor. Zum einen fordern die B{\"u}rger nach den Maximen „Mitmachen, Mitwirken, Mitentscheiden" deutlich verbesserte Partizipationsm{\"o}glichkeiten ein. Zum anderen setzen die Kommunen verst{\"a}rkt auf b{\"u}rgerschaftliches Engagement zur Erschließung Ressourcen privater Akteure f{\"u}r die Bereitstellung {\"o}ffentlicher Leistungen. {\"U}bergreifende Perspektive ist die Ausbildung einer Neuen Partizipationskultur in der B{\"u}rgerkommune zur Optimierung des Gemeinwohls. F{\"u}r die kommunale Praxis ist das partizipationsgest{\"u}tzte Miteinander von Verwaltung. Politik und B{\"u}rgerschaft in Systementw{\"u}rfen, Leitbildern, Organisations- und Verfahrensmodellen sowie lokalen Beteiligungsformaten konkretisiert. Doch verbinden sich mit den alten und neuen Ans{\"a}tzen der B{\"u}rgerbeteiligung noch eine ganze Reihe offener Fragen - so etwa nach den rechtlichen M{\"o}glichkeiten und Grenzen der neuen kommunalen Beteiligungskultur, nach Erfolgsbedingungen und konkreten Erfahrungen mit der Umsetzung von Partizipationsmodellen. Auf der 21. Fachtagung des Kommunalwissenschaftlichen Instituts (KWI) der Universit{\"a}t Potsdam wurden Schl{\"u}sselthemen der Neuen Partizipationskultur in der B{\"u}rgerkommune, namentlich der normativen Rahmenbedingungen und politischen Direktiven, Modernisierungsimpulse und Aktivierungsstrategien, Erfolgsbedingungen und spezifische Problemlagen einschließlich der Fallstricke in der Praxis und nicht zuletzt ausgew{\"a}hlter Einsatzfelder mit den dazugeh{\"o}rigen Erfahrungen diskutiert.}, language = {de} }