bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lyapunov's second method in problems of the stability of solutions of systems with impulse effect
Authors: Ignatyev Alexander O. 
Published: October 2008

AbstractA system of ordinary differential equations with impulse effect at fixed moments of time is considered. The system is assumed to have the zero solution. It is shown that the existence of a corresponding Lyapunov function is a necessary and sufficient condition for the uniform asymptotic stability of the zero solution. Restrictions on perturbations of the right‐hand sides of differential equations and impulse effects are obtained under which the uniform asymptotic stability of the zero solution of the ‘unperturbed’ system implies the uniform asymptotic stability of the zero solution of the ‘perturbed’ system. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cosymmetric families of steady states in 3D convection of incompressible fluid in a porous medium
Authors: Tsybulin V. G. , Nemtsev A. D. , Karasözen B. 
Published: October 2008

AbstractWe consider three‐dimensional convection of an incompressible fluid saturated in a parallelepiped with a porous medium. A mimetic finite‐difference scheme for the Darcy convection problem in the primitive variables is developed. Two problems with different boundary conditions are considered to study scenarios of instability of the state of rest. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A numerical method for soluble surfactants on moving interfaces
Authors: Khatri Shilpa , Tornberg Anna‐Karin 
Published: October 2008

AbstractWe present a numerical method modeling soluble surfactants on deforming interfaces. The method uses an explicit Eulerian discretization of the interface allowing the use of standard finite difference schemes to solve coupled time‐dependent differential equations for the concentration of surfactant on the interface and for the concentration of surfactant in the bulk. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modelling and quantifying bifurcation diagrams of Chua's oscillator
Authors: Dittmar Jörg , Parlitz Ulrich 
Published: October 2008

AbstractWe present methods for evaluating bifurcation diagrams that were reconstructed from time series generated by the system of interest at different fixed parameter values. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vortex wake mitigation of an airfoil with winglets by active rudders
Authors: Schöll Robert , Hörnschemeyer Ralf , Henke Rolf 
Published: October 2008

AbstractThe wake vortex hazard and the required separation distances between aircraft at airports constitute an impediment to the growth of air traffic at major hubs. One approach to reduce separation distances is the exploitation of the inherent instability in vortex systems, leading to an accelerated breakdown. In this paper we show the impact of excitation by different control surfaces on the stability behavior of the wake of a rectangular wing with winglets. The experiment shows that the excitation through winglet rudders and ailerons yields the best results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A discontinuous Galerkin method for the Wigner‐Fokker‐Planck equation with a non‐polynomial approximation space
Authors: Sharp Richard , Gualdani Maria Pia , Gamba Irene 
Published: October 2008

AbstractA discontinuous Galerkin approach to the Wigner‐Fokker‐Planck equation, a model for quantum devices including environmental effects, is proposed. Evaluation of a pseudo‐differential term is the main challenge. The approach can be applied to a variety of potential functions and uses general approximation spaces. Simulations using the method are in agreement with established analytic results and produce reasonable solutions for several potentials. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Damping of structural vibrations using an electromotive eddy current damper
Authors: Siewert Christian , Panning Lars , Hohl Andreas , Bürge Annika , Gerber Christoph 
Published: October 2008

AbstractStructural vibrations are normally the cause for high cycle fatigue failure (HCF) in technical structures. For example, the blades of rotating bladed turbine disks are subjected to fluctuating gas forces during operation that cause blade vibrations. Therefore, one of the main tasks in the design of turbomachinery blading is the reduction of the vibration amplitudes of the blades and it is well known that the vibration amplitudes can be reduced significantly to a reasonable amount by means of friction damping devices such as underplatform dampers, tip shrouds and damping wires. If the temperature of the working fluid is not excessively high, the use of an electromotive eddy current damper can be a possible alternative to this well known classical friction damping devices. If a conducting material is moving in a stationary magnetic field, eddy currents are generated inside the conductor. These eddy currents cause an energy dissipation effect and damping forces are generated. This damping effect can be used to reduce the resonance amplitudes and therefore to decrease the risk of a HCF failure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Relationship between aortic isthmus and ductus venosus velocity waveforms in severe growth restricted fetuses
Authors: Rizzo Giuseppe , Capponi Alessandra , Vendola Marianne , Pietrolucci Maria Elena , Arduini Domenico 
Published: October 2008

AbstractObjectiveTo evaluate the incidence of abnormalities in velocity waveforms from ductus venosus (DV) and aortic isthmus (AoI) in fetuses with intrauterine growth restriction (IUGR) and their reciprocal temporal relationship.MethodsDV and AoI velocity waveforms were recorded in 31 IUGR fetuses characterized either by absent end diastolic (20) or reverse flow (11) in umbilical artery. Abnormal velocity waveforms in DV and AoI were defined in presence of reverse diastolic flows.ResultsAbnormal DV velocity waveforms were present in 10 fetuses and were always associated with abnormalities. Abnormal AoI flows were also present in 10 fetuses of the remaining 21 fetuses with normal DV velocity waveforms (47.6%). Longitudinal monitoring of fetuses with normal DV flows showed a significantly shorter time interval in the onset of reverse flow in DV when abnormalities in AoI were present (4 vs 14 days p = 0.001) irrespectively of gestational age or other potential confounding variables.ConclusionsOur data suggest that AoI velocity waveforms become abnormal at an earlier stage of fetal compromise than DV. Copyright © 2008 John Wiley & Sons, Ltd.
Longitudinal study of platelet size changes in gestation and predictive power of elevated MPV in development of pre‐eclampsia
Authors: Dundar Ozgur , Yoruk Pinar , Tutuncu Levent , Akyol Erikci Alev , Muhcu Murat , Ergur Ali Rustu , Atay Vedat , Mungen Ercument 
Published: October 2008

AbstractObjectivesThe aim of this cohort is to investigate whether any haematologic changes detectable by simple complete blood count (CBC) precede pre‐eclampsia development and the diagnostic value of these markers in clinical practice for prediction of pre‐eclampsia.MethodsAll pregnant women, in the first trimester, attending to GATA Haydarpasa Teaching Hospital Obstetric Outpatient Clinic for routine obstetric care were enrolled. Routine obstetric care consisted of monthly visits until 32nd week, bimonthly visits between 32nd and 36th week, and weekly thereafter. According to the study, protocol CBC was taken from women at each visit and recorded. After delivery, outcome data were obtained.ResultsA total of 1336 women were included into the statistical analysis and 107 (8%) of them developed pre‐eclampsia. Parameters of CBC were similar between groups other than mean platelet volume (MPV) values. MPV values of pre‐eclamptic women were significantly higher than normotensive counterparts from 24th gestational week up to gestational week at birth. In pre‐eclamptic group, mean gestational age of diagnosis was 33.8 weeks and significant MPV increase was detected to precede the diagnosis by approximately 4.6 weeks (range 2.8–5.9 weeks).ConclusionsOur study provides evidence that MPV gradually increases in pregnant women affected by pre‐eclampsia compared to women with normal pregnancies. Copyright © 2008 John Wiley & Sons, Ltd.
Compatibility and biocompatibility study of new HPC/PU blends
Authors: Raschip Irina Elena , Vasile Cornelia , Macocinschi Doina 
Published: October 2008

AbstractBACKGROUND: Polymer blending is one of the most useful methods for the improvement or modification of the physicochemical properties of polymeric materials without altering the structure and function of individual polymers. The blends between biopolymers and synthetic polymers are of particular significance because they can combine biocompatibility with good processability and mechanical resistance and can be used as biomaterials. The aim of the blending of hydroxypropylcellulose (HPC) and polyurethane (PU) is to find applications for newly synthesized PUs and also to create new materials with possible medical applications and enhanced surface properties.RESULTS: Films containing mostly HPC or mostly PU are found to be homogeneous and transparent, while for the intermediate composition range a morphology of a fine dispersion in a continuous matrix is characteristic. The values of the blood–biomaterial interfacial tension (γSL) are in the range 1.96–3.27 mN m−1, which allows us to conclude that these materials have a good haemocompatibility.CONCLUSION: The thermomechanical and morphological behaviour were explored and specific interactions were evident between the PU blocks and the HPC chains especially in the 60% HPC–20% HPC/40% PU–80% PU composition range because of the high degree of compatibility. The blends obtained are not cytotoxic and exhibit good surface properties and haemocompatibility. Therefore they could be candidates for medical and pharmaceutical applications. Copyright © 2008 Society of Chemical Industry
Entspiegelung nach dem Vorbild von Mottenaugen
Authors: Lohmüller Theobald , Spatz Joachim P. , Brunner Robert 
Published: October 2008

AbstractMotten finden ihre Nahrung in der Dämmerung, ohne sich durch Lichtreflexion auf ihren Facettenaugen zu verraten – und liefern dabei ein faszinierendes Beispiel für die Anwendungsmöglichkeiten von Nanotechnologie. Forscher am Max‐Planck‐Institut für Metallforschung in Stuttgart haben jetzt in Kooperation mit der Carl Zeiss AG in Jena ein Verfahren entwickelt, um künstliche Mottenaugenstrukturen auf optische Materialien zu übertragen.
Farbfotos durch Interferenz
Authors: Jacobi Manfred 
Published: October 2008

AbstractGabriel Lippmann erhielt im Jahr 1908 den Nobelpreis für Physik für seine “Methode, Farben auf photographischem Weg mittels des Phänomens der Interferenz zu reproduzieren”. Seine Methode erregt damals großes Aufsehen, konnte sich aber nicht durchsetzen.
Asymmetrien in der Natur. Physik‐Nobelpreis 2008
Authors: Schmelling Michael 
Published: October 2008

AbstractDer diesjährige Nobelpreis für Physik geht an Yoichiro Nambu, Makoto Kobayashi und Toshihide Maskawa. Die Forscher werden für ihre Arbeiten zur Symmetriebrechung in der Elementarteilchenphysik ausgezeichnet. Diese sind von zentraler Bedeutung für das Verständnis der Wechselwirkungen zwischen den bekannten Feldern und der Existenz des uns bekannten Universums.
Farbenprächtige Sonnentaler auf dem Wasser
Authors: Schlichting H.‐Joachim 
Published: October 2008

AbstractWährend normale Sonnentaler so alltäglich sind, wie die Sonne, die sich in ihnen abbildet, muss man schon etwas Glück haben, um farbige Sonnentaler auf einer Wasseroberfläche zu erblicken. Dann können auch die physikalisch hoch interessanten Quételet‐Ringe sichtbar werden.
SESAME – ein Traum nimmt Gestalt an
Authors: Schopper Herwig 
Published: October 2008

AbstractAls vor zehn Jahren die ersten Diskussionen über ein Zentrum für Synchrotronstrahlung im Mittleren Osten begannen, hielten dies viele für ein aussichtsloses Unternehmen – nicht zuletzt wegen der angespannten politischen Situation. In den letzten Jahren wurden jedoch so große Fortschritte erzielt, dass das Projekt SESAME (Synchrotron‐light for Experimental Science and Applications in the Middle East) auf einem guten Weg ist. Am 3. November soll das in Allaan, Jordanien, stehende Gebäude offiziell eingeweiht werden. Die Inbetriebnahme der Anlage ist für Ende 2011 geplant.
Paramagnetismus von flüssigem Sauerstoff
Authors: Pichler Stefan , Schalk Thomas , Hassler Karl 
Published: October 2008

AbstractDas Verhalten einer Substanz in einem Magnetfeld liefert wichtige Erkenntnisse über die Anordnung ihrer Elektronen. Moleküle mit einem oder mehreren freien (ungepaarten) Elektronen werden in ein Magnetfeld hineingezogen, sie sind paramagnetisch. Ein einfacher Versuch verdeutlicht dies an flüssigem Sauerstoff.
Seerosenfloß und “Hausboot”
Authors: Müller Andreas 
Published: October 2008

AbstractDas Auftriebsgesetz spielt in vielen Bereichen unseres Alltags eine Rolle – meistens unbeachtet. Archimedes soll es entdeckt haben, als er von König Hieron II. von Syrakus damit beauftragt wurde, die Echtheit einer neuen Goldkrone zu untersuchen. Hier geht es um zwei Anwendungen des Auftriebs – eine vergnüglich, die andere zerstörerisch, beide überraschend.
Engineered measles virus as a novel oncolytic therapy against prostate cancer
Authors: Msaouel Pavlos , Iankov Ianko D. , Allen Cory , Morris John C. , von Messling Veronika , Cattaneo Roberto , Koutsilieris Michael , Russell Stephen J. , Galanis Evanthia 
Published: October 2008

AbstractBACKGROUNDNo curative therapy is currently available for locally advanced or metastatic prostate cancer. Oncolytic viruses represent a novel class of therapeutic agents that demonstrates no cross‐resistance with existing approaches and can therefore be combined with conventional treatment modalities. Measles virus strains deriving from the Edmonston (MV‐Edm) vaccine strain have shown considerable oncolytic activity against a variety of solid tumers and hematologic malignancies. In this study, we investigated the antitumor potential of recombinant MV‐Edm derivatives as novel oncolytic agents against prostate cancer.METHODSThe susceptibility of prostate cancer cell lines (PC‐3, DU‐145, and LNCaP) to measles virus infection was demonstrated using an MV‐Edm derivative expressing green fluorescent protein (GFP). MV‐Edm replication in prostate cancer cell lines was assessed by one step viral growth curves. The oncolytic effect of an MV‐Edm strain engineered to express the human carcinoembryonic antigen (CEA) was demonstrated in vitro by MTT assays and in vivo in subcutaneous PC‐3 xenografts. CEA levels were quantitated in cell supernatants and mouse serum samples.RESULTSRecombinant MV‐Edm strains can effectively infect, replicate in and kill prostate cancer cells. Intratumoral administration of MV‐CEA at a total dose of 6 × 106 TCID50 resulted in statistically significant tumor growth delay (P = 0.004) and prolongation of survival (P = 0.001) in a subcutaneous PC‐3 xenograft model. Viral growth kinetics paralleled CEA production.CONCLUSIONSMV‐CEA has potent antitumor activity against prostate cancer cell lines and xenografts. Viral gene expression during treatment can be determined by monitoring of CEA levels in the serum; the latter could allow dose optimization and tailoring of individualized treatment protocols. Prostate 69: 82–91, 2009. © 2008 Wiley–Liss, Inc.
Cryopreservation of prostate cancer tissue during routine processing of fresh unfixed prostatectomy specimen: demonstration and validation of a new technique
Authors: Schäfer Stephan C. , Pfnür Maria , Yerly Stephane , Fandel Thomas M. , Jichlinski Patrice , Lehr Hans‐Anton 
Published: October 2008

AbstractBACKGROUNDMost molecular techniques currently require fresh frozen tumor tissue, which in the case of prostatectomy specimen is a challenge to obtain for a variety of intrinsic reasons. Prostate cancers are usually located in the organ periphery and hence meticulous attention has to be paid to the relation between the tumor and the surgical margin. In this article we describe a new technique that allows to obtain fresh frozen tumor material in rather large quantities and without jeopardizing diagnostic accuracy.METHODAn inner triangle, representing roughly 50% of the entire prostate tissue, is removed from native prostatectomy specimen and cryopreserved, leaving the periphery of the organ for routine histomorphological analysis. We have validated the technique using a series of 180 archived radical prostatectomy specimen that had been studied by histology in their entirety, as well as 42 prostatectomy specimen worked‐up by the new technique.RESULTSThe described technique is effective, yielding frozen tumor tissue in 84.2% of unilateral (≤pT2b) and in 91.8% of bilateral (pT2c) carcinomas. The number of tumor containing tissue blocks ranged from 1 to 7 blocks per carcinoma (mean 5.6 ± 3.2). The remaining peripheral tissue portion subjected to histological analysis allowed to estimate total tumor volume with a high degree to confidentiality (r2 ≥ 0.90 by linear regression analysis). The number of blocks to be routinely examined for each prostatectomy specimen is significantly reduced, thus saving costs without loss of diagnostic accuracy.CONCLUSIONThe described technique for prostate cancer cryoconservtion is feasible, highly standardized, effective, safe, and economic. Prostate 69: 191–197, 2009. © 2008 Wiley–Liss, Inc.
MEH‐PPV photobleaching control by femtosecond pulse shaping
Authors: Ferreira Paulo Henrique D. , Silva Daniel L. , Misoguti Lino , Mendonca Cleber R. 
Published: October 2008

AbstractIn the work reported here we were able to control the photobleaching of poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylene vinylene] (MEH‐PPV), excited by two‐photon absorption, using femtosecond pulse shaping. By applying a cosine‐like spectral phase mask, we observe a reduction of three times in the photobleaching rate, while the fluorescence intensity decreases by 20%, in comparison to the values obtained with a Fourier‐transform‐limited pulse. These results demonstrate an interesting trade‐off between photobleaching rate and nonlinear fluorescence intensity. The possible mechanism behind this process is discussed in terms of the pulse spectral profile and the absorbance band of MEH‐PPV. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low‐temperature change of lattice parameters in LiKB4O7 single crystals
Authors: Adamiv Volodymyr , Burak Yaroslav , Teslyuk Ihor 
Published: October 2008

AbstractStructural investigations of LiKB4O7 crystals in the 13–290 K temperature range have been carried out by means of the high‐resolution powder diffraction technique applying synchrotron radiation. It is shown that the structural phase transitions are absent and all the linear thermal expansion coefficients αij are positive in the investigated temperature range. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron paramagnetic resonance investigation on Zn1–xMnx O thin films grown by MBE
Authors: Knies Christoph , Stehr Jan , Hofmann Detlev M. , Xu Wei , Zhou Yingxue , Zhang Xinyi 
Published: October 2008

AbstractWe present the results of an electron paramagnetic resonance (EPR) study on Zn1–x Mnx O thin films grown by molecular beam epitaxy on sapphire substrates. The Mn concentrations in the samples vary between x = 0.03 and x = 0.3. Our results show a dominant antiferromagnetic coupling of the Mn2+ ions. The obtained Curie‐Weiss temperatures are consistently smaller compared to results of earlier investigations, this is likely to be caused by an inhomogeneous distribution of the Mn2+ ions in the samples. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin polarized transport driven by square voltage pulses in a quantum dot system
Authors: Souza Fabrício M. , Gomez Javier A. 
Published: October 2008

AbstractWe calculate current, spin current and tunnel magnetoresistance (TMR) for a quantum dot coupled to ferromagnetic leads in the presence of a square wave of bias voltage. Our results are obtained via time‐dependent nonequilibrium Green function for a non‐interacting electron model. Both parallel and antiparallel lead magnetization alignments are considered. The main findings include a wave of spin accumulation and spin current that can change sign as the time evolves, spikes in the TMR signal and a TMR sign change due to an ultrafast switch from forward to reverse current in the emitter lead. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ocean altimeter assimilation with observational‐ and model‐bias correction
Authors: Lea D. J. , Drecourt J.‐P. , Haines K. , Martin M. J. 
Published: October 2008

AbstractWe implement a combined on‐line model‐ and observation‐bias correction scheme in the UK Met Office Forecasting Ocean Assimilation Model (FOAM) Unified Model ocean data assimilation system. The observation bias is designed to estimate the error in the mean dynamic topography that is used for altimeter data assimilation. In future, this mean dynamic topography and its errors may be derived from the Gravity field and steady‐state Ocean Circulation Explorer (GOCE) mission geoid data. The mean dynamic topography field is added to the altimeter data supplied as sea‐level anomalies, giving the absolute dynamic topography. The model‐bias scheme separately estimates the remaining bias in the model's sea surface height field. The final unbiased estimate of the absolute dynamic topography is assimilated into the FOAM model by adjusting the subsurface density field using the Cooper and Haines scheme. Various diagnostics, including the observation minus background statistics, show that both model‐ and observation‐bias correction schemes improve the assimilation results. Combining the schemes provides better results than either used alone. Copyright © 2008 Royal Meteorological Society and Crown Copyright, 2008
A generalized thermal wind equation and some non‐separable exact solutions of the flow equations for three‐dimensional spherical atmospheres
Authors: White A. A. , Staniforth A. 
Published: October 2008

AbstractSteady axisymmetric flows in geostrophic and cyclostrophic balance under gravity are considered for the three‐dimensional Euler equations (with the spherical geopotential approximation but without the shallow‐atmosphere and ‘traditional’ approximations). The key to analytical specification of these flows is a compatibility condition involving the zonal flow and temperature fields. This condition is a generalization of the thermal wind equation for balanced zonal flow governed by the hydrostatic primitive equations. Two examples are presented in which the temperature field is specified as non‐separable two‐parameter functions of latitude and height, and corresponding zonal flows are derived analytically. Such flows extend the class of known analytical solutions of the governing equations, and their usefulness in numerical model development and testing is the focus of this study. © Crown Copyright 2008. Reproduced with the permission of the Controller of HMSO. Published by John Wiley & Sons, Ltd.