254 results match your criteria: "Universitt[Affiliation]"

Calculating the motion of highly confined, arbitrary-shaped particles in Hele-Shaw channels.

Microfluid Nanofluidics

July 2018

1Center for Extreme Matter and Emergent Phenomena, Institute for Theoretical Physics, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands.

We combine theory and numerical calculations to accurately predict the motion of anisotropic particles in shallow microfluidic channels, in which the particles are strongly confined in the vertical direction. We formulate an effective quasi-two-dimensional description of the Stokes flow around the particle via the Brinkman equation, which can be solved in a time that is two orders of magnitude faster than the three-dimensional problem. The computational speedup enables us to calculate the full trajectories of particles in the channel.

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Investigation of Naturally Occurring Single-Nucleotide Variants in Human TAAR1.

Front Pharmacol

November 2017

Institute of Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, Freie Universität Berlin, Humboldt-Universitt zu Berlin, Berlin, Germany.

Activation of trace amine-associated receptor 1 (TAAR1) in endocrine pancreas is involved in weight regulation and glucose homeostasis. The purpose of this study was the identification and characterization of potential variants in patients with overweight/obesity and disturbed glucose homeostasis. Screening for variants was performed in 314 obese or overweight patients with impaired insulin secretion.

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Mechanical characterisation of oocytes - The influence of sample geometry on parameter identification.

J Mech Behav Biomed Mater

January 2018

Institute of Solid Mechanics, Technische Universitt Braunschweig, Braunschweig D-38106, Germany. Electronic address:

The present study focused on the material characterisation of porcine oocytes by experiments combined with an inverse finite-element method (iFEM) approach. In doing so, two different deformation states, compression and indentation, were realised to enable the validation of the numerical model. In addition to classical force-strain relations, geometrical information on the oocyte's surface and volume changes during deformation were collected.

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Configurational Disorder of Water Hydrogen-Bond Network at the Protein Dynamical Transition.

J Phys Chem B

July 2017

Laboratoire de Biochimie Théorique, IBPC, CNRS UPR9080, Univ. Paris Diderot, Sorbonne Paris Cité , 13 rue Pierre et Marie Curie, 75005 Paris, France.

We introduce a novel strategy to quantify the disorder of extended water-water hydrogen-bond (HB) networks sampled in particle-based computer simulations. The method relies on the conformational clustering of the HB connectivity states. We successfully applied it to unveil the fine relationship among the protein dynamical transition in hydrated powder, which marks the activation of protein flexibility at T ≈ 240 K, and the sudden increase in the configurational disorder of the water HB network enveloping the proteins.

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Interdependence of ICD rates in paired quantum dots on geometry.

J Comput Chem

September 2017

Institute of Methods for Material Development, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, Berlin, 12489, Germany.

Using state-of-the-art antisymmetrized multiconfiguration time-dependent Hartree (MCTDH) electron dynamics calculations we study the interdependence of the intermolecular Coulombic decay (ICD) process on the geometric parameters of a doubly-charged paired quantum dot (PQD) model system in the framework of the effective mass approximation (EMA). We find that ICD displays a maximum rate for a certain geometry of the electron-emitting quantum dot, which is simultaneously dependent on both the distance between the quantum dots as well as the photon-absorbing quantum dot's geometry. The rate maximum is shown to be caused by the competing effects of polarization of electron density and Coulomb repulsion.

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Gα proteins Gvm2 and Gvm3 regulate vegetative growth, asexual development, and pathogenicityon apple in Valsa mali.

PLoS One

September 2017

State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, People's Republic of China.

In fungi, heterotrimeric guanine-nucleotide binding proteins (G-proteins) are key elements of signal transduction pathways, which control growth, asexual and sexual development, as well as virulence. In this study, we have identified two genes encoding heterotrimeric G protein alpha subunits, named Gvm2 and Gvm3, from Valsa mali, the causal agent of apple Valsa canker. Characterization of Gvm2 and Gvm3 mutants indicates that Gvm3 may be a crucial regulator of vegetative growth.

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(HO)SbBr: the first member of the MEX structure family with oxonium cations.

Acta Crystallogr C Struct Chem

December 2016

Department of Chemistry and Food Chemistry, Technische Universitt Dresden, Helmholtzstrasse 10, Dresden, Sachsen 01069, Germany.

(HO)SbBr [trihydroxonium enneabromidodiantimonate(III)] is the first representative of the MEX family (M = cation, E = Sb and Bi, and X = Br and I) with oxonium cations. The metastable compound was obtained in trace amounts from a solution of CsBr and SbBr in concentrated aqueous HBr. Single crystals were isolated from the mother liquor and investigated by single-crystal X-ray diffraction at 100 K.

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In this study, we demonstrated the suitability of direct injection mass spectrometry headspace analysis for rapid non-invasive quality control of semi-finished dairy ingredients, such as skim milk powder (SMP), whole milk powder (WMP), whey powder (WP) and anhydrous milk fat (AMF), which are widely used as ingredients in the food industry. In this work, for the first time, we applied proton transfer reaction-mass spectrometry (PTR-MS) with a time-of-flight (ToF) analyzer for the rapid and non-invasive analysis of volatile compounds in different samples of SMP, WMP, WP and AMF. We selected different dairy ingredients in various concrete situations (e.

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Sub-Femto-g Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results.

Phys Rev Lett

June 2016

Institut für Geophysik, ETH Zürich, Sonneggstrasse 5, CH-8092, Zürich, Switzerland.

We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2±0.

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We have characterized the photodetection capabilities of single GaN nanowires incorporating 20 periods of AlN/GaN:Ge axial heterostructures enveloped in an AlN shell. Transmission electron microscopy confirms the absence of an additional GaN shell around the heterostructures. In the absence of a surface conduction channel, the incorporation of the heterostructure leads to a decrease of the dark current and an increase of the photosensitivity.

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Urethral stricture in men is a common disorder, negatively affecting the health and therefore the quality of patients life. The aim of the study was to evaluate the nature of the stricture in various segments of male urethra and the incidence rate of urethral stricture in the Republic of Uzbekistan. The study presents the analysis of medical records of 195 men (mean age 40,6+/-13,1 years) who underwent urethroplasty in the Republican Specialized Centre of Urology between February 2013 and March 2015.

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Logarithmic Mean Temperature Profiles and Their Connection to Plume Emissions in Turbulent Rayleigh-Bénard Convection.

Phys Rev Lett

October 2015

Physics of Fluids Group, Faculty of Science and Technology, J. M. Burgers Centre for Fluid Dynamics, University of Twente, P. O. Box 217, 7500 AE Enschede, Netherlands.

Two-dimensional simulations of Rayleigh-Bénard convection at Ra=5×10^{10} show that vertical logarithmic mean temperature profiles can be observed in regions of the boundary layer where thermal plumes are emitted. The profile is logarithmic only in these regions and not in the rest of the boundary layer where it is sheared by the large-scale wind and impacted by plumes. In addition, the logarithmic behavior is not visible in the horizontal average.

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Monitoring of lactic fermentation driven by different starter cultures via direct injection mass spectrometric analysis of flavour-related volatile compounds.

Food Res Int

October 2015

Department of Food Quality and Nutrition, Research and Innovation Centre, Fondazione Edmund Mach (FEM), via E. Mach 1, 38010 San Michele all'Adige, Italy. Electronic address:

In this work, we used Proton Transfer Reaction-Mass Spectrometry (PTR-ToF-MS), coupled with an automated sampling system, to monitor lactic fermentation driven by different yogurt commercial starter cultures via direct injection mass spectrometric analysis of flavour-related volatile compounds. The aim is the identification of markers for real-time and non-invasive bioprocess control and optimisation as an industrial driver of innovation in food technology and biotechnology. We detected more than 300 mass peaks, tentatively identifying all major yogurt aroma volatiles.

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Regional climate modeling using convection-permitting models (CPMs; horizontal grid spacing <4 km) emerges as a promising framework to provide more reliable climate information on regional to local scales compared to traditionally used large-scale models (LSMs; horizontal grid spacing >10 km). CPMs no longer rely on convection parameterization schemes, which had been identified as a major source of errors and uncertainties in LSMs. Moreover, CPMs allow for a more accurate representation of surface and orography fields.

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WITHDRAWN: Fascicle switching: a conserved pattern of axogenesis in the panarthropod brain.

Arthropod Struct Dev

April 2015

Developmental Neurobiology Group, Biocenter, Ludwig-Maximilians-Universitt, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany.

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org10.

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Patterns of late spring frost leaf damage and recovery in a European beech (Fagus sylvatica L.) stand in south-eastern Germany based on repeated digital photographs.

Front Plant Sci

March 2015

Ecoclimatology, Department of Ecology and Ecosystem Management, Technische Universitt Mnchen Freising, Germany ; Biological and Environmental Sciences, School of Natural Sciences, University of Stirling Stirling, UK.

Damage by late spring frost is a risk deciduous trees have to cope with in order to optimize the length of their growing season. The timing of spring phenological development plays a crucial role, not only at the species level, but also at the population and individual level, since fresh new leaves are especially vulnerable. For the pronounced late spring frost in May 2011 in Germany, we studied the individual leaf development of 35 deciduous trees (mainly European beech Fagus sylvatica L.

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Introduction: Pelvic ± para-aortic lymphadenectomy (LAE) is an essential element of staging and treatment of different gynecologic malignancies. However, LAE can induce asymptomatic and symptomatic pelvic lymphoceles (LCs) in a considerable percentage of patients. Therapy of symptomatic LCs may cause additional morbidity.

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When a new in vitro assay method is introduced, it should be validated against the best available knowledge or a reference standard assay. For assays resulting in a simple binary outcome, the data can be displayed as a 2×2 table. Based on the estimated sensitivity and specificity, and the assumed prevalence of true positives in the population of interest, the positive and negative predictive values of the new assay can be calculated.

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MyMpn: a database for the systems biology model organism Mycoplasma pneumoniae.

Nucleic Acids Res

January 2015

Universitat Pompeu Fabra (UPF), Dr. Aiguader 88, 08003 Barcelona, Spain CRG Bioinformatics Facility, Centre for Genomic Regulation (CRG), Dr. Aiguader 88, 08003 Barcelona, Spain

MyMpn (http://mympn.crg.eu) is an online resource devoted to studying the human pathogen Mycoplasma pneumoniae, a minimal bacterium causing lower respiratory tract infections.

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In widefield fluorescence microscopy, images from all but very flat samples suffer from fluorescence emission from layers above or below the focal plane of the objective lens. Structured illumination microscopy provides an elegant approach to eliminate this unwanted image contribution. To this end a line grid is projected onto the sample and phase images are taken at different positions of the line grid.

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Effect of polyelectrolytes on (de)stability of liquid foam films.

Soft Matter

September 2014

Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut fr Chemie, Technische Universitt Berlin, Strasse des 17.Juni 124, D-10623 Berlin, Germany.

The review addresses the influence of polyelectrolytes on the stabilisation of free-standing liquid foam films, which affects the stability of a whole macroscopic foam. Both the composition of the film surface and the stratification of the film bulk drives the drainage and the interfacial forces within a foam film. Beside synthetic polyelectrolytes also natural polyelectrolytes like cellulose, proteins and DNA are considered.

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Sources of nitrous and nitric oxides in paddy soils: nitrification and denitrification.

J Environ Sci (China)

March 2014

School of Geography Sciences, Nanjing Normal University, Nanjing 210097, China. Electronic address:

Rice-paddies are regarded as one of the main agricultural sources of N 2O and NO emissions. To date, however, specific N2O and NO production pathways are poorly understood in paddy soils. (15)N-tracing experiments were carried out to investigate the processes responsible for N2O and NO production in two paddy soils with substantially different soil properties.

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Perfect absorbers on curved surfaces and their potential applications.

Opt Express

July 2012

Institute of Condensed Matter Theory and Solid State Optics, Abbe Center of Photonics, Friedrich-Schiller-Universitt Jena, Jena 07743, Germany.

Recently perfect metamaterial absorbers triggered some fascination since they permit the observation of an extreme interaction of light with a nanostructured thin film. For the first time we evaluate here the functionality of such perfect absorbers if they are applied on curved surfaces. We probe their optical response and discuss potential novel applications.

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Motivation: It has been recognized that the topology of molecular networks provides information about the certainty and nature of individual interactions. Thus, network motifs have been used for predicting missing links in biological networks and for removing false positives. However, various different measures can be inferred from the structure of a given network and their predictive power varies depending on the task at hand.

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