bluuebunny/crossref_metadata_2025_split huggingface dataset:
Micro‐Perforated Panels – Assessing the Sound Absorption
Authors: Stremtan Florina‐Anca , Lupea Iulian 
Published: November 2013

AbstractNowadays micro‐perforated panels (MPP) are continuously gaining interest in terms of the efficient design, simulation and the acoustic energy absorption capacity. The MPP construction and functionality is based on the Helmholtz resonator. The present article presents and discusses a couple sets of MPPs made of plastic and wood of different design. The analyzed MPP samples have different geometrical parameters such as the microperforation diameter, the panel thickness and the distance between holes. The MPP structure is coupled with sound‐absorbing materials of different thicknesses which are partially or completely filling the air between the perforated plate and the backing rigid surface. A series of measurements performed by using the impedance tube, in order to determine the sound absorption coefficient are mentioned. The mathematical modeling approaches are presented with references to the Maa theory and experimental models like the one developed by Delany and Bazley. The coupling effort for design, mathematical modelling and experimental validation will ends into conclusions and preferred absorbing structure proposals for the highest sound absorption effciency and for the widest frequency band. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identification of optimal material models and parameters in finite strain plasticity
Authors: Vladimirov Ivaylo N. , Bambach Markus , Herty Michael , Bücker H. Martin 
Published: November 2013

AbstractThe numerical simulation of the behaviour of a workpiece during manufacturing depends to a large extent on the quality of the applied material model. In this work, a method for the identification of constitutive models and material parameters in engineering applications is proposed. The presented method is used in the setting of optimal experimental design and is based on successive optimization of a set of finite strain plasticity models with kinematic and/or isotropic hardening. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A kinetic model for polytropic gases with internal energy
Authors: Boudin Laurent , Grec Bérénice , Pavić‐Čolić Milana , Salvarani Francesco 
Published: November 2013

AbstractWe consider a mixture of N ideal, polytropic gases. Each species is described by a distribution function fi(t, x, v, I) ≥ 0, 1 ≤ i ≤ N, defined on ${\rm I\!R}_+\times{\rm I\!R}^3\times{\rm I\!R}^3\times{\rm I\!R}_+$, and its evolution is governed by a Boltzmann‐type equation. In order to recover the energy law of polytropic gases, the authors of [4] proposed a kinetic model in the framework of a weighted L1 space. Another approach has been developed in [3] in the context of polyatomic gases. Following this previous lead, our model provides a L2 framework in both variables v and I, to eventually perform a mathematical study of the diffusion asymptotics, as it was done in [2] for a model without energy exchange. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Reachability and Observability Concepts for Stochastic Systems
Authors: Benner Peter , Redmann Martin 
Published: November 2013

AbstractWe define observability and reachability and introduce the corresponding Gramians for a Levy driven linear system like Benner, Damm in [3] which focused on the case of Wiener noise. We additionally show that the sets of observable and reachable states are characterized by these Gramians. This is analogous to deterministic systems, where observability and reachability concepts are described in Sections 4.2.1 and 4.2.2 in Antoulas [1]. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimization for discretized switched systems
Authors: Flaßkamp Kathrin , Murphey Todd , Ober‐Blöbaum Sina 
Published: November 2013

AbstractSwitching time optimization is a crucial topic in the optimal control of hybrid systems. Since it is rare that such problems can be solved analytically, the use of numerical discretization schemes for the integration of state and adjoint systems is indispensable. Thus, in this contribution, the switching time optimization problem is studied in a discretized formulation directly from the beginning. An analysis of the discretized problem reveals that smoothness of the original (continuous time) problem is lost, i.e. the problem will in general become nondifferentiable in discrete time. This has to be taken into account when deriving an adjoint‐based formula for the optimization of the discretized problem. A hybrid double pendulum example is used for illustration of the results. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preconditioning of Krylov subspace methods using recycling in Lattice QCD computations
Authors: Bolten Matthias , Božović Nemanja , Frommer Andreas 
Published: November 2013

AbstractMany applications in computational science and engineering require the solution of sequences of slowly changing linear systems. We focus on problems arising in Lattice QCD simulations. In order to generate an ensemble of configurations from which the values of physical observables can be obtained, we have to solve a linear system with a Dirac operator in each time step of the hybrid Monte‐Carlo simulations. This operator changes just slightly from time step to time step. While recycling subspace information from the previous system like described in [1] reduces the number of necessary matrix‐vector multiplications, the systems are still expensive to solve. To overcome this limitation, we include preconditioning in our implementation. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Reduced Basis Method for an Elastic Buckling Problem
Authors: Zanon Lorenzo , Veroy‐Grepl Karen 
Published: November 2013

AbstractIn this work, we apply the Reduced Basis (RB) Method to the field of nonlinear elasticity. In this first stage of research, we analyze a buckling problem for a compressed 2D column: Here, the trivial linear solution is computed for an arbitrary load; the critical load, marking the transition to nonlinearity, is then identified through an eigenvalue problem. The linear problem satisfies the Lax‐Milgram conditions, allowing the implementation of both a Successive Constraint Method for an inexpensive lower bound of the coercivity constant and of a rigorous and efficient a posteriori error estimator for the RB approximation. Even though only a non‐rigorous estimator is available for the buckling problem, the actual RB approximation of the output is more than satisfactory, and the gain in computational efficiency significant. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Efficient solver for swirling flow problems in ducts with variable radius
Authors: Dragomirescu Florica Ioana , Susan‐Resiga Romeo , Muntean Sebastian 
Published: November 2013

AbstractThe paper presents preliminary results of a work in progress addressing the hydrodynamic stability of swirling flows problems in ducts with variable radius which imply mathematical modeling, dynamic and stability investigations. The proposed quasi‐analytical method aims to obtain the velocity profiles with a low order approximation method of which the computation costs were neglijable and regain the central stagnation zone developed in the fluid. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal parameter choice for the pole condition
Authors: Ruprecht Daniel , Schädle Achim , Schmidt Frank 
Published: November 2013

AbstractThe pole condition is a framework for the derivation of transparent boundary conditions that identifies non‐physical modes by the location of the corresponding singularities in the complex plane of the solution's spatial Laplace transform. A complex half‐plane is then defined that contains all poles corresponding to non‐physical modes. A key parameter in the pole condition arises in the Möbius transformation that maps this half‐plane onto the complex unit circle. The effect of variations in this parameter on the quality of the approximate TBC realized by the pole condition is explored here for the two‐dimensional drift‐diffusion equation with inhomogeneous coefficients. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Funnel Control for Linear DAEs
Authors: Berger Thomas 
Published: November 2013

AbstractWe study funnel control for linear differential‐algebraic multi‐input multi‐output systems which are not necessarily regular. We show that the funnel controller (that is a static nonlinear output error feedback) achieves ‐ for a special class of right‐invertible systems with asymptotically stable zero dynamics ‐ tracking of a reference signal by the output signal within a pre‐specified performance funnel. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Finslerian extensions of geodesic active fields for digital image registration
Authors: Balan Vladimir , Stojanov Jelena 
Published: November 2013

AbstractThe present work extends the already established prolific geodesic active field methodology of Riemannian type, which generalizes the Casseles‐Kimmel‐Sapiro weighted length problem, and a direction dependent Finslerian structure is proposed as alternative for the GAF image registration process. The proposed extension relies on the direction‐dependent 0‐homogeneous associated weight metric tensor and aims to achieve the minimization of the absolute error in the case of motion detection. (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Aerodynamic focusing of inertial particles in supersonic micronozzles
Authors: Rybdylova Oyuna , Lebedeva Natalya , Kudryavtsev Alexey , Shershnev Anton 
Published: November 2013

AbstractA particle‐laden flow in a supersonic micronozzle is studied using a one‐way coupled two‐fluid approach. The carrier gas parameters are obtained from the numerical solution of the Navier‐Stokes equations, rarefaction effects are taken into account by imposing velocity slip and temperature jump boundary conditions on the nozzle walls. Under conditions considered, the flow around particles is transitional and free‐molecular. As a result of numerical solution of the dispersed‐phase equations in Lagrangian variables, two types of particle motion in the expanding part of the nozzle are detected: particle spraying and particle accumulation. The particle focusing effect is most pronounced for particles of about 1–2 µm in size. The particle number density fields contain singularities appearing on the envelopes of particle trajectories. However, the model of non‐colliding particles remains valid because the mean distance between the particles near the singularities remains much greater than the particle size. The aerodynamic scheme of aerosol particle focusing proposed may be used in various technologies (microthrusters, needle‐free drug injection, microfabrication, etc.). (© 2013 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
MicroRNA‐30b functions as a tumour suppressor in human colorectal cancer by targeting KRAS, PIK3CD and BCL2
Authors: Liao Wen‐Ting , Ye Ya‐Ping , Zhang Nian‐Jie , Li Ting‐Ting , Wang Shu‐Yang , Cui Yan‐Mei , Qi Lu , Wu Ping , Jiao Hong‐Li , Xie Yi‐Jun , Zhang Chi , Wang Jun‐Xian , Ding Yan‐Qing 
Published: November 2013

AbstractColorectal cancer (CRC) is the third most common cancer in the USA. MicroRNAs play important roles in the pathogenesis of CRC. In this study, we investigated the role of miR‐30b in CRC and found that its expression was significantly lower in CRC tissues than that in normal tissues. We showed that a low expression level of miR‐30b was closely related to poor differentiation, advanced TNM stage and poor prognosis of CRC. Further experiments showed that over‐expression of miR‐30b suppressed CRC cell proliferation in vitro and tumour growth in vivo. Specifically, miR‐30b promoted G1 arrest and induced apoptosis. Moreover, KRAS, PIK3CD and BCL2 were identified as direct and functional targets of miR‐30b. MiR‐30b directly targeted the 3′‐untranslated regions of their mRNAs and repressed their expression. This study revealed functional and mechanistic links between miRNA‐30b and oncogene KRAS, PIK3CD and BCL2 in the pathogenesis of CRC. MiR‐30b not only plays important roles in the regulation of cell proliferation and tumour growth in CRC, but is also a potential prognostic marker or therapeutic target for CRC. Restoration of miR‐30b expression may represent a promising therapeutic approach for targeting malignant CRC. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
A host deficiency of discoidin domain receptor 2 (DDR2) inhibits both tumour angiogenesis and metastasis
Authors: Zhang Shuya , Bu Xin , Zhao Hu , Yu Jiangtian , Wang Yingmei , Li Di , Zhu Chuchao , Zhu Tong , Ren Tingting , Liu Xinping , Yao Libo , Su Jin 
Published: November 2013

AbstractDiscoidin domain receptor 2 (DDR2) is a unique receptor tyrosine kinase (RTK) that signals in response to collagen binding and is implicated in tumour malignant phenotypes such as invasion and metastasis. Although it has been reported that DDR2 expression is up‐regulated in activated endothelial cells (ECs), functional studies are lacking. Herein, we found that enforced expression of DDR2 promoted proliferation, migration and tube formation of primary human umbilical vein endothelial cells (HUVECs). The results of immunohistochemical analysis showed a strikingly high level of DDR2 in human tumour ECs. Most significantly, we discovered that a host deficiency of DDR2 inhibits subcutaneous angiogenesis induced by either VEGF or tumour cells. In addition, the remaining tumour vessels in DDR2‐deficient mice exhibit some normalized properties. These vascular phenotypes are accompanied by the up‐regulation of anti‐angiogenic genes and down‐regulation of pro‐angiogenic genes, as well as by alleviated tumour hypoxia. By use of a tail vein metastasis model of melanoma, we uncovered that loss of stromal DDR2 also suppresses tumour metastasis to the lung. Hence, our current data disclose a new mechanism by which DDR2 affects tumour progression, and may strengthen the feasibility of targeting DDR2 as an anticancer strategy. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Fabrication of zinc oxide nanowires/polymer composites by two‐photon polymerization
Authors: Fonseca Ruben Dario , Correa Daniel Souza , Paris Elaine Cristina , Tribuzi Vinicius , Dev Apurba , Voss Tobias , Aoki Pedro Henrique Benites , Constantino Carlos Jose Leopoldo , Mendonca Cleber Renato 
Published: November 2013

ABSTRACTWe present an approach to fabricate ZnO nanowires/polymer composite into three‐dimensional microstructures, based on two‐photon polymerization direct laser writing, a fabrication method that allows submicrometric spatial resolution. The structural integrity of the structures was inferred by scanning electron microscopy, while the presence and distribution of ZnO nanowires was investigated by energy dispersive X‐ray, Raman spectroscopy, and X‐ray diffraction. The optical properties of the produced composite microstructures were verified by imaging the characteristic ZnO emission using a fluorescence microscope. Hence, such approach can be used to develop composite microstructures containing ZnO nanowires aiming at technological applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci. Part B: Polym. Phys. 2014, 52, 333–337
Human α1β3γ2L gamma‐aminobutyric acid type A receptors: High‐level production and purification in a functional state
Authors: Dostalova Zuzana , Zhou Xiaojuan , Liu Aiping , Zhang Xi , Zhang Yinghui , Desai Rooma , Forman Stuart A. , Miller Keith W. 
Published: November 2013

AbstractGamma‐aminobutyric acid type A receptors (GABAARs) are the most important inhibitory chloride ion channels in the central nervous system and are major targets for a wide variety of drugs. The subunit compositions of GABAARs determine their function and pharmacological profile. GABAARs are heteropentamers of subunits, and (α1)2(β3)2(γ2L)1 is a common subtype. Biochemical and biophysical studies of GABAARs require larger quantities of receptors of defined subunit composition than are currently available. We previously reported high‐level production of active human α1β3 GABAAR using tetracycline‐inducible stable HEK293 cells. Here we extend the strategy to receptors containing three different subunits. We constructed a stable tetracycline‐inducible HEK293‐TetR cell line expressing human (N)–FLAG–α1β3γ2L–(C)–(GGS)3GK–1D4 GABAAR. These cells achieved expression levels of 70–90 pmol [3H]muscimol binding sites/15‐cm plate at a specific activity of 15–30 pmol/mg of membrane protein. Incorporation of the γ2 subunit was confirmed by the ratio of [3H]flunitrazepam to [3H]muscimol binding sites and sensitivity of GABA‐induced currents to benzodiazepines and zinc. The α1β3γ2L GABAARs were solubilized in dodecyl‐d‐maltoside, purified by anti‐FLAG affinity chromatography and reconstituted in CHAPS/asolectin at an overall yield of ∼30%. Typical purifications yielded 1.0–1.5 nmoles of [3H]muscimol binding sites/60 plates. Receptors with similar properties could be purified by 1D4 affinity chromatography with lower overall yield. The composition of the purified, reconstituted receptors was confirmed by ligand binding, Western blot, and proteomics. Allosteric interactions between etomidate and [3H]muscimol binding were maintained in the purified state.
Delousing efficiency of farmed ballan wrasse (Labrus bergylta) against Lepeophtheirus salmonis infecting Atlantic salmon (Salmo salar) post‐smolts
Authors: Leclercq Eric , Davie Andrew , Migaud Hervé 
Published: November 2013

AbstractBACKGROUNDCleaner‐fish (wrasse, Labridae) are increasingly deployed within the Atlantic salmon (Salmo salar L.) industry as a biological control against sea‐lice (Lepeophtheirus salmonis Krøyer). Two tank‐based trials were performed to test the effect of farmed ballan wrasse (Labrus bergylta Ascanius) body mass and supplementary feeding on the delousing of Atlantic salmon post‐smolts with an initial infection level of ∼12 lice salmon−1 and a ∼5% wrasse:salmon ratio.RESULTSSea‐louse levels below 0.5 lice salmon−1 were obtained within 84 h, and preferential preying upon larger motile stages was found. The wrasse body mass and the availability of fresh, opened blue mussels (Mytilus edulis L.) did not significantly affect delousing efficiency. The functional predator response was linear, showing no minimum prey density threshold for sea‐louse foraging and no satiation plateau, in spite of the high consumption rates measured. Sea‐louse infection levels declined following a one‐phase exponential decay model, with a standardised decline time constant of 0.8–1.3% h−1 for each wrasse stocked per 100 salmon.CONCLUSIONSFarmed ballan wrasse are confirmed as highly effective therapeutic and preventive biological controls against sea‐lice. The study supports the current minimum hatchery size target (10 mm total length) and the use of supplementary feeding to sustain the wrasse stocks in operation. The functional predator response and the standardised decline time constant of sea‐louse abundance are proposed as useful indicators of delousing efficiency. © 2013 Society of Chemical Industry
TIMING OF REDD CONSTRUCTION BY FALL CHINOOK SALMON IN THE HANFORD REACH OF THE COLUMBIA RIVER
Authors: Hayes D. B. , Bellgraph B. J. , Roth B. M. , Dauble D. D. , Mueller R. P. 
Published: November 2013

ABSTRACTSpawning habits of fall Chinook salmon in the Hanford Reach of the Columbia River have been documented with annual aerial surveys since 1948. We developed a series of models analysing these data, exploring the influence of environmental factors on the timing of redd construction. These models included a logistic regression and a dynamic modelling approach, with combinations of day of year (as a surrogate for environmental cues such as day length), water temperature and discharge as potential explanatory factors. Results of these analyses indicate that day of year was the strongest predictor of the timing of redd construction, but with significant modifying effects of water temperature and discharge. The dynamic modelling approach provides substantial advantages over a traditional logistic regression, including (1) the ability to treat data collected at non‐synchronous time intervals in a consistent fashion and (2) the ability to easily implement complex functions (e.g., threshold responses) relating behaviour to environmental cues. Evaluation of the series as a whole indicates that the median date of redd construction has increased over time, from approximately day 299 in 1950 to day 307 in 2010, as has the temperature on Oct 1 (16.3 °C–18.1 °C). The degree to which these changes are caused by climate change or dam operations is uncertain, however. Copyright © 2013 John Wiley & Sons, Ltd.
Toward a Theory of Experience
Authors: ROTH WOLFF‐MICHAEL , JORNET ALFREDO 
Published: November 2013

ABSTRACTExperience is one of the most used terms in (science) education, and it is recognized as being related to learning (education). Yet what experience is and how it is related to learning and change remains untheorized. In this paper, we mainly draw on the work of J. Dewey and L. S. Vygotsky but also on M. Bakhtin and more recent advances on the topic of experience from French philosophy to contribute to a theory of this important category. Accordingly, experience is not something that belongs to or is had by individuals but rather denotes transactions in and across space and time within irreducible person‐in‐setting units; and it is perfused with an affect that is not (only) the result of mental constructions. An episode from an Australian physics classroom is used to exemplify what such a theory and its method‐related implications have to accomplish in the analysis of concrete science lessons.
A generic homomorphic MAC construction for authentication in network coding
Authors: Wang Weijia , Hu Lei 
Published: November 2013

ABSTRACTIn this paper, we propose a generic homomorphic MAC scheme on the basis of linear mapping over finite fields. Benefiting from its algebra characteristics, our scheme is more flexible and effective than the previous schemes based on the vector inner product or the trace function over finite fields. Copyright © 2013 John Wiley & Sons, Ltd.