Refine
Year of publication
- 2014 (1681) (remove)
Document Type
- Article (1122)
- Doctoral Thesis (202)
- Postprint (102)
- Monograph/Edited Volume (55)
- Review (54)
- Preprint (47)
- Conference Proceeding (42)
- Part of a Book (19)
- Part of Periodical (14)
- Other (11)
Language
Is part of the Bibliography
- yes (1681) (remove)
Keywords
- anomalous diffusion (14)
- prevention (10)
- radiation mechanisms: non-thermal (9)
- Eye movements (8)
- Holocene (8)
- gamma rays: galaxies (8)
- living cells (8)
- Earthquake source observations (7)
- gamma rays: general (7)
- violence (7)
Institute
- Institut für Biochemie und Biologie (246)
- Institut für Physik und Astronomie (237)
- Institut für Geowissenschaften (226)
- Institut für Chemie (188)
- Department Psychologie (90)
- Wirtschaftswissenschaften (59)
- Institut für Ernährungswissenschaft (58)
- Sozialwissenschaften (55)
- Institut für Mathematik (53)
- Historisches Institut (50)
- Institut für Informatik und Computational Science (45)
- Department Sport- und Gesundheitswissenschaften (44)
- Department Linguistik (36)
- Hasso-Plattner-Institut für Digital Engineering gGmbH (28)
- Mathematisch-Naturwissenschaftliche Fakultät (24)
- Strukturbereich Kognitionswissenschaften (22)
- Institut für Anglistik und Amerikanistik (21)
- Humanwissenschaftliche Fakultät (20)
- Institut für Romanistik (20)
- Bürgerliches Recht (19)
- Institut für Germanistik (19)
- Öffentliches Recht (17)
- Institut für Umweltwissenschaften und Geographie (15)
- Philosophische Fakultät (12)
- Department Erziehungswissenschaft (10)
- Extern (9)
- Klassische Philologie (8)
- Referat für Presse- und Öffentlichkeitsarbeit (8)
- Institut für Jüdische Studien und Religionswissenschaft (6)
- Institut für Künste und Medien (5)
- Strafrecht (5)
- MenschenRechtsZentrum (4)
- Institut für Slavistik (3)
- Kommunalwissenschaftliches Institut (3)
- Department Grundschulpädagogik (2)
- Fachgruppe Politik- & Verwaltungswissenschaft (2)
- Fachgruppe Soziologie (2)
- Institut für Philosophie (2)
- Universitätsbibliothek (2)
- WeltTrends e.V. Potsdam (2)
- Wirtschafts- und Sozialwissenschaftliche Fakultät (2)
- Zentrum für Qualitätsentwicklung in Lehre und Studium (ZfQ) (2)
- Arbeitskreis Militär und Gesellschaft in der Frühen Neuzeit e. V. (1)
- Department Musik und Kunst (1)
- Dezernat 2: Studienangelegenheiten (1)
- Hasso-Plattner-Institut für Digital Engineering GmbH (1)
- Juristische Fakultät (1)
- Strukturbereich Bildungswissenschaften (1)
- Zentrum für Lehrerbildung und Bildungsforschung (ZeLB) (1)
The CH2Cl2/MeOH (1: 1) extract of the roots of Tephrosia villosa showed good antiplasmodial activity against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 3.1 +/- 0.4 and 1.3 +/- 0.3 mu g/mL, respectively. Chromatographic separation of the extract yielded a new rotenoid, 6 alpha-hydroxy-alpha-toxicarol, along with five known rotenoids, (rotenone, deguelin, sumatrol, 12 alpha-hydroxy-alpha-toxicarol and villosinol). Similar treatment of the extract of the stem of Tephrosia purpurea (IC50 = 4.1 +/- 0.4 and 1.9 +/- 0.2 mu g/mL against D6 and W2 strains of P. falciparum, respectively) yielded a new flavone having a unique substituent at C-7/C-8 [trivial name (+)-tephrodin], along with the known flavonoids tachrosin, obovatin methyl ether and derrone. The relative configuration and the most stable conformation in (+)-tephrodin was determined by NMR and theoretical energy calculations. The rotenoids and flavones tested showed good to moderate antiplasmodial activities (IC50 = 9 +/- 23 mu M). Whereas the cytotoxicity of rotenoids is known, the flavones (+)-tephrodin and tachrosin did not show significant cytotoxicity (IC50 > 100 mu M;) against mammalian African monkey kidney (vero) and human larynx carcinoma (HEp2) cell lines. (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.
2013 jährte sich das Inkrafttreten der Europäischen Menschenrechtskonvention zum 60. Mal. Seit ihrem Bestehen hat die Konvention insbesondere durch den auf ihrer Grundlage gegründeten Gerichtshof den Schutz der Menschenrechte in Europa wesentlich gestärkt. Mit ihren mittlerweile 47 Vertragsparteien ist sie zu einem gesamteuropäischen Grundrechtsschutzsystem geworden, dessen Akzeptanz sich nicht zuletzt an den in den vergangenen Jahren rasant gestiegenen Fallzahlen zeigt. Dennoch steht die EMRK auch in der Zukunft vor besonderen Herausforderungen. Dieser Band stellt den Versuch einer Bilanz der vergangenen 60 Jahre dar und enthält die Beiträge der Vortragenden des Workshops „60 Jahre Europäische Menschenrechtskonvention – die Konvention als ‚living instrument‘“, der anlässlich des Jubiläums durch das MenschenRechtsZentrum der Universität Potsdam veranstaltet wurde. Schwerpunktmäßig beschäftigen sich die Beiträge mit der Rechtsfortbildung durch den EGMR, insbesondere mittels einer dynamischen Auslegung der Konvention, der konstitutionellen Dimension der EMRK, der Durchsetzung seiner Urteile sowie dem Reformbedarf aufgrund gestiegener Arbeitsbelastung.
Diatom diversity in lakes of northwest Yakutia (Siberia) was investigated by microscopic and genetic analysis of surface and cored lake sediments, to evaluate the use of sedimentary DNA for paleolimnological diatom studies and to identify obscure genetic diversity that cannot be detected by microscopic methods. Two short (76 and 73 bp) and one longer (577 bp) fragments of the ribulose 1,5-bisphosphate carboxylase/oxygenase (rbcL) gene, encoding the large subunit of the rbcL, were used as genetic markers. Diverse morphological assemblages of diatoms, dominated by small benthic fragilarioid taxa, were retrieved from the sediments of each lake. These minute fragilarioid taxa were examined by scanning electron microscopy, revealing diverse morphotypes in Staurosira and Staurosirella from the different lakes. Genetic analyses indicated a dominance of haplotypes that were assigned to fragilarioid taxa and less genetic diversity in other diatom taxa. The long rbcL_577 amplicon identified considerable diversification among haplotypes clustering within the Staurosira/Staurosirella genera, revealing 19 different haplotypes whose spatial distribution appears to be primarily related to the latitude of the lakes, which corresponds to a vegetation and climate gradient. Our rbcL markers are valuable tools for tracking differences between diatom lineages that are not visible in their morphologies. These markers revealed putatively high genetic diversity within the Staurosira/Staurosirella species complex, at a finer scale than is possible to resolve by microscopic determination. The rbcL markers may provide additional reliable information on the diversity of barely distinguishable minute benthic fragilarioids. Environmental sequencing may thus allow the tracking of spatial and temporal diversification in Siberian lakes, especially in the context of diatom responses to recent environmental changes, which remains a matter of controversy.
Downscaling of microfluidic cell culture and detection devices for electrochemical monitoring has mostly focused on miniaturization of the microfluidic chips which are often designed for specific applications and therefore lack functional flexibility. We present a compact microfluidic cell culture and electrochemical analysis platform with in-built fluid handling and detection, enabling complete cell based assays comprising on-line electrode cleaning, sterilization, surface functionalization, cell seeding, cultivation and electrochemical real-time monitoring of cellular dynamics. To demonstrate the versatility and multifunctionality of the platform, we explored amperometric monitoring of intracellular redox activity in yeast (Saccharomyces cerevisiae) and detection of exocytotically released dopamine from rat pheochromocytoma cells (PC12). Electrochemical impedance spectroscopy was used in both applications for monitoring cell sedimentation and adhesion as well as proliferation in the case of PC12 cells. The influence of flow rate on the signal amplitude in the detection of redox metabolism as well as the effect of mechanical stimulation on dopamine release were demonstrated using the programmable fluid handling capability. The here presented platform is aimed at applications utilizing cell based assays, ranging from e.g. monitoring of drug effects in pharmacological studies, characterization of neural stem cell differentiation, and screening of genetically modified microorganisms to environmental monitoring.
Downscaling of microfluidic cell culture and detection devices for electrochemical monitoring has mostly focused on miniaturization of the microfluidic chips which are often designed for specific applications and therefore lack functional flexibility. We present a compact microfluidic cell culture and electrochemical analysis platform with in-built fluid handling and detection, enabling complete cell based assays comprising on-line electrode cleaning, sterilization, surface functionalization, cell seeding, cultivation and electrochemical real-time monitoring of cellular dynamics. To demonstrate the versatility and multifunctionality of the platform, we explored amperometric monitoring of intracellular redox activity in yeast (Saccharomyces cerevisiae) and detection of exocytotically released dopamine from rat pheochromocytoma cells (PC12). Electrochemical impedance spectroscopy was used in both applications for monitoring cell sedimentation and adhesion as well as proliferation in the case of PC12 cells. The influence of flow rate on the signal amplitude in the detection of redox metabolism as well as the effect of mechanical stimulation on dopamine release were demonstrated using the programmable fluid handling capability. The here presented platform is aimed at applications utilizing cell based assays, ranging from e.g. monitoring of drug effects in pharmacological studies, characterization of neural stem cell differentiation, and screening of genetically modified microorganisms to environmental monitoring.
Time-delayed collection field (TDCF) and bias-amplified charge extraction (BACE) are applied to as-prepared and annealed poly(3-hexylthiophene):[6,6]-phenyl C-71 butyric acid methyl ester (P3HT:PCBM) blends coated from chloroform. Despite large differences in fill factor, short-circuit current, and power conversion efficiency, both blends exhibit a negligible dependence of photogeneration on the electric field and strictly bimolecular recombination (BMR) with a weak dependence of the BMR coefficient on charge density. Drift-diffusion simulations are performed using the measured coefficients and mobilities, taking into account bimolecular recombination and the possible effects of surface recombination. The excellent agreement between the simulation and the experimental data for an intensity range covering two orders of magnitude indicates that a field-independent generation rate and a density-independent recombination coefficient describe the current-voltage characteristics of the annealed P3HT: PCBM devices, while the performance of the as-prepared blend is shown to be limited by space charge effects due to a low hole mobility. Finally, even though the bimolecular recombination coefficient is small, surface recombination is found to be a negligible loss mechanism in these solar cells.
This study compares the duration and first two formants (F1 and F2) of 11 nominal monophthongs and five nominal diphthongs in Standard Southern British English (SSBE) and a Northern English dialect. F1 and F2 trajectories were fitted with parametric curves using the discrete cosine transform (DCT) and the zeroth DCT coefficient represented formant trajectory means and the first DCT coefficient represented the magnitude and direction of formant trajectory change to characterize vowel inherent spectral change (VISC). Cross-dialectal comparisons involving these measures revealed significant differences for the phonologically back monophthongs /D, , , u:/ and also /3z:/ and the diphthongs /eI, e, aI, I/. Most cross-dialectal differences are in zeroth DCT coefficients, suggesting formant trajectory means tend to characterize such differences, while first DCT coefficient differences were more numerous for diphthongs. With respect to VISC, the most striking differences are that /u:/is considerably more diphthongized in the Northern dialect and that the F2 trajectory of /e/proceeds in opposite directions in the two dialects. Cross-dialectal differences were found to be largely unaffected by the consonantal context in which the vowels were produced. The implications of the results are discussed in relation to VISC, consonantal context effects and speech perception. (c) 2014 Acoustical Society of America.
We consider an extension of the Standard Model within the framework of Noncommutative Geometry. The model is based on an older model [C. A. Stephan, Phys. Rev. D 79, 065013 (2009)] which extends the Standard Model by new fermions, a new U(1)-gauge group and, crucially, a new scalar field which couples to the Higgs field. This new scalar field allows to lower the mass of the Higgs mass from similar to 170 GeV, as predicted by the Spectral Action for the Standard Model, to a value of 120-130 GeV. The shortcoming of the previous model lay in its inability to meet all the constraints on the gauge couplings implied by the Spectral Action. These shortcomings are cured in the present model which also features a "dark sector" containing fermions and scalar particles.