bluuebunny/crossref_metadata_2025 huggingface dataset:
Delineating coastal groundwater discharge processes in a wetland area by means of electrical resistivity imaging, 224Ra and 222Rn
Authors: Zarroca Mario , Linares Rogelio , Rodellas Valentí , Garcia‐Orellana Jordi , Roqué Carles , Bach Joan , Masqué Pere
Published: March 2013

Coastal groundwater discharge (CGD) plays an important role in coastal hydrogeological systems as they are a water resource that needs to be managed, particularly in wetland areas. Despite its importance, identifying and monitoring CGD often presents physical and logistical constraints, restraining the application of more traditional submarine groundwater discharge surveying techniques. Here we investigate the capability of electrical resistivity imaging (ERI) in the Peníscola wetland (Mediterranean coast, Spain). ERI surveying made it possible to identify and delineate an ascending regional groundwater flow of thermal and Ra‐enriched groundwater converging with local flows and seawater intrusion. The continuous inputs of Ra‐rich groundwater have induced high activities of Ra isotopes and 222Rn into the marsh area, becoming among the highest previously reported in wetlands and coastal lagoons. Geoelectrical imaging enabled inferring focused upward discharging areas, leaking from the aquifer roof through a confining unit and culminating as spring pools nourishing the wetland system. Forward modelling over idealized subsurface configurations, borehole datasets, potentiometric records from standpipe piezometers, petrophysical analysis, and four natural and independent tracers (224Ra, 222Rn, temperature and salinity) permitted assessing the geoelectrical model and a derived hydrogeological pattern. The research highlights the potential of ERI to improve hydrogeological characterization of subsurface processes in complex contexts, with different converging flows. Additionally, a hydrogeological conceptual model for a groundwater‐fed coastal wetland was proposed, based on the integration of surveying datasets. Copyright © 2013 John Wiley & Sons, Ltd.
Proposal to Formulate “Global Informal Workout Rules” Adopting “Asian Bankers' Association Informal Workout Guidelines” and “Model Agreement to Promote Company Restructuring by Informal Workout” with Some Minor Amendments
Authors: Takagi Shinjiro
Published: February 2013

The INSOL 8 Principles is a set of model domestic rules for out‐of‐court workouts. Many Asian countries have created workout rules referring to the Principles. A uniform insolvency code applicable worldwide may be impossible to achieve. Instead, international professional associations such as the INSOL International and/or official international organizations such as the World Bank may be able to establish global informal workout rules that are applicable in cases to restructure multinational business enterprises that are indebted to multinational financial creditors. The “Asian Bankers' Association Informal Workout Guidelines” and the “Model Agreement to Promote Company Restructuring by Informal Workout” of 2005 are buried treasure tools. They could be transformed to global rules with some minor amendments with the consent of the Association. Copyright © 2013 INSOL International and John Wiley & Sons, Ltd
Dual‐wavelength excitation for fluorescence‐based quantification of zinc protoporphyrin IX and protoporphyrin IX in whole blood
Authors: Hennig Georg , Gruber Christian , Vogeser Michael , Stepp Herbert , Dittmar Stephan , Sroka Ronald , Brittenham Gary M.
Published: March 2013

Quantification of erythrocyte zinc protoporphyrin IX (ZnPP) and protoporphyrin IX (PPIX), individually or jointly, is useful for the diagnostic evaluation of iron deficiency, iron‐restricted erythropoiesis, lead exposure, and porphyrias. A method for simultaneous quantification of ZnPP and PPIX in unwashed blood samples is described, using dual‐wavelength excitation to effectively eliminate background fluorescence from other blood constituents. In blood samples from 35 subjects, the results of the dual‐wavelength excitation method and a reference high performance liquid chromatography (HPLC) assay were closely correlated both for ZnPP (rs = 0.943, p < 0.0001; range 37–689 μmol ZnPP/mol heme, 84–1238 nmol/L) and for PPIX (rs = 0.959, p < 0.0001; range 42–4212 μmol PPIX/mol heme, 93–5394 nmol/L). In addition, for ZnPP, the proposed method is compared with conventional single‐wavelength excitation and with commercial front‐face fluorimetry of washed erythrocytes and whole blood. We hypothesize that dual‐wavelength excitation fluorimetry will provide a new approach to the suppression of background fluorescence in blood and tissue measurements of ZnPP and PPIX. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photoacoustic imaging in attenuating acoustic media based on strongly causal models
Authors: Kalimeris Konstantinos , Scherzer Otmar
Published: February 2013

In this paper, we derive time reversal imaging functionals for two strongly causal acoustic attenuation models, which have been proposed recently. The time reversal techniques are based on recently proposed ideas of Ammari et al. for the thermo‐viscous wave equation. Here and there, an asymptotic analysis provides reconstruction functionals from first order corrections for the attenuating effect. In addition, we present a novel approach for higher order corrections. Copyright © 2013 John Wiley & Sons, Ltd.
Impact of the frequency response fluctuations of the multimode fiber on the OFDM transmission
Authors: Maksymiuk Lukasz , Wisnicki Bartosz
Published: February 2013

Described is an analysis of the frequency response fluctuations of the multimode fiber impact on the Orthogonal frequency division multiplexing (OFDM) transmission. There is provided theory, numerical calculations and measurements. We analyze extreme and moderate frequency response fluctuation cases. Orthogonal frequency division multiplexing transmission is possible even in pass band when the spatial light filtration is moderate. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:845–849, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27402
Terahertz‐wave absorber based on metamaterial
Authors: Jiu‐Sheng Li
Published: February 2013

We theoretically and numerically study the absorption effect of a metamaterial absorber in the terahertz region.An equivalent circuit model is proposed to estimate the absorption characteristics of the metamaterial structures for terahertz wave normally incident on the structure. Theoretical and experimental results show that the absorber has nearly perfect absorption bandwidth of 53.3 GHz and an absorption peak (0.992) at the frequency of 0.734 THz. The good agreement between the measurement results and simulated prediction is observed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:793–796, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27405
Reliable em‐driven microwave design optimization using manifold mapping and adjoint sensitivity
Authors: Koziel Slawomir , Leifsson Leifur , Ogurtsov Stanislav
Published: February 2013

A robust and reliable algorithm for computationally efficient design optimization of microwave structures evaluated with electromagnetic (EM) simulations is introduced. The presented approach utilizes a low‐fidelity model constructed from coarse‐discretization EM simulation of the structure under consideration, as well as cheap derivative information obtained by means of adjoint sensitivity. Adjoint sensitivity is exploited to reduce the misalignment between the low‐ and high‐fidelity models through input space mapping, to construct a first‐order consistent surrogate model through manifold mapping, and to optimize the surrogate through a trust‐region‐based algorithm. This comprehensive use of adjoint sensitivity results in a very low design cost and excellent convergence capability of the proposed algorithm. Efficiency of our approach is demonstrated using two examples: an ultra‐wideband antenna and a microstrip bandpass filter. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:809–813, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27430
CPW‐FED slot antenna for personal mobile communication service (PCS) and bluetooth applications
Authors: Ojaroudi Nasser , Ojaroudi Mohammad
Published: February 2013

A novel design of dual band CPW‐fed slot for personal communication service (PCS) and Bluetooth applications is presented in this article.The proposed antenna is designed to operate at 1.8 GHz, 2.4 GHz, and it is fabricated on the FR4 substrate. In this structure, by cutting a pair of G‐shaped slits in the ground plane we can gave a new resonance at lower frequencies for PCS in handy terminal, which operating at 1.77∼1.88 GHz band, also by embedding a pair of E‐shaped slits at radiating stub, the presented antenna can be created and achieves good dual‐band operation. The measured impedance bandwidth for l0 dB return loss is from 1.73 to 1.84 GHz and 2.33 to 2.45 GHz, covering the 1.8/2.4 GHz for PCS/Bluetooth applications. Simulated and experimental results obtained for this antenna show that the proposed slot antenna has a good antenna gains and radiation behavior within the 1.8/2.4 GHz frequencies. The designed antenna has a small size of 30 × 30 × 0.8 mm3. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:734–737, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27432
Design and implementation of a wideband top loop loaded monopole antenna for mobile handset
Authors: Jung Pil Hyun , Yang Woon Geun
Published: February 2013

In this article, we design a wideband top loop loaded monopole antenna for mobile handset. There is one loop made by a rectangular‐shaped slot on the top of the proposed antenna. The top loop is an asymmetric structure. Owing to the top loop, the antenna can have a huge bandwidth from 1540 to 2610 MHz. A High Frequency Structure Simulator (HFSS) is employed to analyze the proposed antenna in the design process and to compare the simulation and experimental results. The bandwidth of the proposed antenna is measured as 1500–2600 MHz for Voltage Standing Wave Ratio (VSWR) of less than 3. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:779–782, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27443
Dual band high gain monopole antenna for modern mobile devices
Authors: Rezaeieh Sasan Ahdi , Kartal Mesut , Kent Sedef
Published: February 2013

A miniaturized dual‐band antenna with a novel shape in patch and a hybrid design in parasitic plane is presented. The antenna is miniaturized as 22.5 mm × 22.5 mm × 1 mm and operates dual band between 1.7 GHz and 3.7 GHz and 8.4 GHz ∼ 9.6 GHz, that covers DCS (1710–1880 MHz), PCS(1850–1990 MHz), UMTS (1920–2170 MHz), 3G, Wi‐Fi, WLAN, WiMax, and Bluetooth bands. Measurement data attest to the satisfaction of the design specifications. A prototype of antenna is fabricated and a good agreement with simulated results is obtained. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:796–800, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27446
A fiber optic sensor based on air‐gap long period gratings for pH sensing application
Authors: Mau Jiang‐Chiou , Lin Guei‐Ru , Fu Ming‐Yue , Liu Wen‐Fung
Published: February 2013

In this article, a pH fiber‐optic sensor based on an air‐gap long period fiber grating (AG‐LPG) in a multi‐modes fiber is proposed. Owing to the different pH solutions to cause the index variation of surrounding AG‐LPG, the grating wavelength will be shifted due to the change of the effective index both in core and cladding layers. For pH sensing applications, the experimental results show the sensitivity of −0.219 nm/pH and 0.248 nm/pH for measuring the acid and alkaline solutions respectively. This simple sensing head can be applied in a real‐time and long‐term monitoring pH change of drinking water or testing solutions. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:855–857, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27466
A frontal Delaunay quad mesh generator using the L ∞ norm
Authors: Remacle J.‐F. , Henrotte F. , Carrier‐Baudouin T. , Béchet E. , Marchandise E. , Geuzaine C. , Mouton T.
Published: March 2013

In a recent work, a new indirect method to generate all‐quad meshes has been developed. It takes advantage of a well‐known algorithm of the graph theory, namely the Blossom algorithm, which computes in polynomial time the minimum cost perfect matching in a graph. In this paper, we describe a method that allows to build triangular meshes that are better suited for recombination into quadrangles. This is performed by using the infinity norm to compute distances in the meshing process. The alignment of the elements in the frontal Delaunay procedure is controlled by a cross field defined on the domain. Meshes constructed this way have their points aligned with the cross‐field directions, and their triangles are almost right everywhere. Then, recombination with the Blossom‐based approach yields quadrilateral meshes of excellent quality. Copyright © 2013 John Wiley & Sons, Ltd.
Movement of deep‐sea coral populations on climatic timescales
Authors: Thiagarajan Nivedita , Gerlach Dana , Roberts Mark L. , Burke Andrea , McNichol Ann , Jenkins William J. , Subhas Adam V. , Thresher Ronald E. , Adkins Jess F.
Published: February 2013

During the past 40,000 years, global climate has moved into and out of a full glacial period, with the deglaciation marked by several millennial‐scale rapid climate change events. Here we investigate the ecological response of deep‐sea coral communities to both glaciation and these rapid climate change events. We find that the deep‐sea coral populations of Desmophyllum dianthus in both the North Atlantic and the Tasmanian seamounts expand at times of rapid climate change. However, during the more stable Last Glacial Maximum, the coral population globally retreats to a more restricted depth range. Holocene populations show regional patterns that provide some insight into what causes these dramatic changes in population structure. The most important factors are likely responses to climatically driven changes in productivity, [O2] and [CO32–].
Impact of native defects in high‐k dielectric oxides on GaN/oxide metal–oxide–semiconductor devices
Authors: Choi Minseok , Lyons John L. , Janotti Anderson , Van de Walle Chris G.
Published: March 2013

We perform first‐principles calculations to investigate the electronic structure of native defects in various oxide dielectrics to address the impact of defects on GaN/oxide metal–oxide–semiconductor (MOS) devices. We calculate defect formation energies in Al2O3, HfO2, and LaAlO3, as a function of the chemical potentials and of the Fermi‐level position in the band gap. By aligning the conduction‐band and valence‐band edges of these oxides to those of GaN, the role of native defect as charge‐trap or fixed‐charge centers in GaN‐based MOS devices is examined. We find that oxygen vacancies in the oxide dielectrics result in charge‐state transition levels near the GaN conduction‐band edge. They can therefore introduce border traps and/or leakage current through the gate dielectric in the n‐GaN/oxide MOS devices such as MOS field‐effect‐transistors. While the transition levels for other defects are well away from the GaN conduction‐band edge, these defects are stable in non‐neutral charge states and thus act as sources of fixed charge in MOS devices.
Stochastic service systems, random interval graphs and search algorithms
Authors: Eschenfeldt Patrick , Gross Ben , Pippenger Nicholas
Published: February 2013

We consider several stochastic service systems, and study the asymptotic behavior of the moments of various quantities that have application to models for random interval graphs and algorithms for searching for an idle server or for an vacant or occupied waiting station. In some cases the moments turn out to involve Lambert series for the generating functions for the sums of powers of divisors of positive integers. For these cases we are able to obtain complete asymptotic expansions for the moments of the quantities in question. © 2013 Wiley Periodicals, Inc. Random Struct. Alg., 45, 421–442, 2014
New public key cryptosystems based on non‐Abelian factorization problems
Authors: Gu Lize , Wang Licheng , Ota Kaoru , Dong Mianxiong , Cao Zhenfu , Yang Yixian
Published: March 2013

Two novel public key encryption schemes based on the non‐Abelian factorization problems were proposed. Both of them are proved to be indistinguishable against adaptively chosen ciphertext attack (IND‐CCA2) in the random oracle models. These constructions have the potential to resist Shor's quantum algorithm attack proposed in 1994 and give affirmative answers for the open question announced by Myasnikov, Shpilrain and Ushakov in 2011. Copyright © 2013 John Wiley & Sons, Ltd.
Multi‐camera‐based security log management scheme for smart surveillance
Authors: Kim Daehoon , Hwang Eenjun , Rho Seungmin
Published: March 2013

In this paper, we propose a new security log management scheme for smart surveillance in a multi‐camera environment. Basically, our security log consist of descriptions for various behavior properties of moving objects, such as motion type, time, and speed in a merged camera view. To generate such security log, we first analyze the input video frame from each surveillance camera and construct a motion vector of interest points in the frame. By analyzing the motion vector, we recognize moving objects and trace their local behavior in the video. On the basis of this analysis, we can calculate various global behavior features of the objects in the merged camera view, which can be acquired by stitching together the frames from multiple camera inputs. Such global behavior features are captured into security logs, which can be used to smartly carry out various surveillance operations such as retrieving objects whose behavior is similar to a query behavior or whose behavior shows predefined abnormality. Because our scheme treats all the objects in the frame independently, it can handle multiple objects simultaneously. We implemented a prototype system and performed various experiments to demonstrate that our scheme can achieve a reasonable performance. Copyright © 2013 John Wiley & Sons, Ltd.
A hill cipher‐based remote data possession checking in cloud storage
Authors: Chen Lanxiang , Guo Gongde , Peng Zhen
Published: March 2013

Cloud storage enables users to access their data at any time anywhere. It has the advantages of high scalability, ease of use, cost effectiveness, and so on. However, the server that stores users' data may not be fully trustworthy. When users store their data in cloud storage, they concern much about data intactness. This is the goal of remote data possession checking schemes. This paper proposes a Hill cipher‐based remote data possession checking scheme. The main idea of the scheme comes from the homomorphism of Hill cipher, namely the tags computed from plaintext blocks can be used to compare with the tags computed from ciphertext blocks. It has several advantages as follows. First, it is efficient in terms of computation and communication. Second, it allows verification without the need for the challenger to compare against the original data. Third, the scheme only needs to store a small amount of metadata and use only small challenges and responses. Finally, it performs data possession checking at the same time it provides confidentiality of data. The security and performance analysis illustrates that the scheme is feasible and effective. Copyright © 2013 John Wiley & Sons, Ltd.
Relative risk regression models with inverse polynomials
Authors: Ning Yang , Woodward Mark
Published: February 2013

The proportional hazards model assumes that the log hazard ratio is a linear function of parameters. In the current paper, we model the log relative risk as an inverse polynomial, which is particularly suitable for modeling bounded and asymmetric functions. The parameters estimated by maximizing the partial likelihood are consistent and asymptotically normal. The advantages of the inverse polynomial model over the ordinary polynomial model and the fractional polynomial model for fitting various asymmetric log relative risk functions are shown by simulation. The utility of the method is further supported by analyzing two real data sets, addressing the specific question of the location of the minimum risk threshold. Copyright © 2013 John Wiley & Sons, Ltd.
Quantitative analysis of human ras localization and function in the fission yeast Schizosaccharomyces pombe
Authors: Bond Michael , Croft Wayne , Tyson Richard , Bretschneider Till , Davey John , Ladds Graham
Published: March 2013

Ras signalling is central to fundamental and diverse cellular processes. In higher eukaryotes ras signalling is highly complex, involving multiple isoforms, regulatory proteins and effectors. As a consequence, the study of ras activity in mammalian systems presents a number of technical challenges. The model organism Schizosaccharomyces pombe has previously proved a key system for the study of human signalling components and provides an ideal model for the study of ras, as it contains just one ras protein (Ras1p), which is non‐essential and controls a number of downstream processes. Here we present data demonstrating the quantitative analysis of three distinct Ras1‐related signalling outputs, utilizing the three most abundant human ras isoforms, H‐Ras, N‐Ras and K‐Ras4B, in Sz. pombe. Further, we have characterized the localization of these three human ras isoforms in Sz. pombe, utilizing quantitative image analysis techniques. These data indicate that all three human ras isoforms are functional in fission yeast, displaying differing localization patterns which correlate strongly with function in the regulation of pheromone response and cell shape. These data demonstrate that such yeast strains could provide powerful tools for the investigation of ras biology, and potentially in the development of cancer therapies. Copyright © 2013 John Wiley & Sons, Ltd.
Cyclicity and variability in prey dynamics strengthens predator numerical response: the effects of vole fluctuations on white stork productivity
Authors: Hušek Jan , Adamík Peter , Albrecht Tomáš , Cepák Jaroslav , Kania Wojciech , Mikolášková Eva , Tkadlec Emil , Stenseth Nils Chr.
Published: February 2013

Theory predicts that optimality of life‐long investment in reproduction is, among other factors, driven by the variability and predictability of the resources. Similarly, during the breeding season, single resource pulses characterized by short periods and high amplitudes enable strong numerical responses in their consumers. However, it is less well established how spatio‐temporal dynamics in resource supplies influence the spatio‐temporal variation of consumer reproduction. We used the common vole (Microtus arvalis)—white stork (Ciconia ciconia) resource—consumer model system to test the effect of increased temporal variation and periodicity of vole population dynamics on the strength of the local numerical response of storks. We estimated variability, cycle amplitude, and periodicity (by means of direct and delayed density dependence) in 13 Czech and Polish vole populations. Cross‐correlation between annual stork productivity and vole abundance, characterizing the strength of the local numerical response of storks, increased when the vole population fluctuated more and population cycles were shorter. We further show that the onset of incubation of storks was delayed during the years of higher vole abundance. We demonstrate that high reproductive flexibility of a generalist consumer in tracking the temporal dynamics of its resource is driven by the properties of the local resource dynamics and we discuss possible mechanisms behind these patterns.
An Application of the LC-LSTM Framework to the Self-esteem Instability Case
Authors: Alessandri Guido , Vecchione Michele , Donnellan Brent M. , Tisak John
Published: March 2013

The present research evaluates the stability of self-esteem as assessed by a daily version of the Rosenberg (Society and the adolescent self-image, Princeton University Press, Princeton, 1965) general self-esteem scale (RGSE). The scale was administered to 391 undergraduates for five consecutive days. The longitudinal data were analyzed using the integrated LC-LSTM framework that allowed us to evaluate: (1) the measurement invariance of the RGSE, (2) its stability and change across the 5-day assessment period, (3) the amount of variance attributable to stable and transitory latent factors, and (4) the criterion-related validity of these factors. Results provided evidence for measurement invariance, mean-level stability, and rank-order stability of daily self-esteem. Latent state-trait analyses revealed that variances in scores of the RGSE can be decomposed into six components: stable self-esteem (40 %), ephemeral (or temporal-state) variance (36 %), stable negative method variance (9 %), stable positive method variance (4 %), specific variance (1 %) and random error variance (10 %). Moreover, latent factors associated with daily self-esteem were associated with measures of depression, implicit self-esteem, and grade point average.
Effect of a Spacer Group on Surface Activity, Salinity and Hardness Tolerance, Mimic Oil Washing Efficiency of Monododecyl Diaryl Disulfonate
Authors: Xing Fengmei , Niu Jinping , Liu Xiaochen , Wang Xiaoyu
Published: February 2013

Three anionic surfactants of the monododecyl diaryl disulfonate type (MDDADS‐n, n = 0, 1, 2) were synthesized. The structural characters of MDDADS‐n surfactants were verified by electrospray ionization/mass spectrometry. The effect of the spacer group on the surface activity, salinity and hardness tolerance and mimic oil washing efficiency were investigated. The results showed that the critical micelle concentration (CMC), surface tension at CMC, C20 and the minimum area per molecule of the anionic surfactants increased when the spacer group length increased. There was less effect on mimic oil washing efficiency of MDDADS‐n when the spacer group changed; meanwhile, they displayed higher mimic oil washing efficiency in salt solution (NaCl or CaCl2) than that of sodium dodecylbenzenesulfonate (SDBS); all MDDADS‐n surfactants showed much lower sensitivity to water hardness than SDBS, what would be beneficial to enhancing oil recovery in a high salinity oil field.
Crude bark extract of Dysozylum alliarium induces alteration in histological structures and VEGF‐C expression in uterus during days 4–7 of gestation in albino rat
Authors: Das Moushumi , Saikia Purba Jyoti , Sarma Hirendra N.
Published: February 2013

Purpose

Crude bark extract (CBE) of Dysoxylum alliarium was tested in vivo for its effects on rat uterus during estrus and day 4–7 of gestation. The purpose is to study the effects of CBE on embryo implantation and VEGF‐C expression during peri‐implantation period to find out possible role of VEGF‐C and embryo implantation.

Methods

Threshold was determined by multiple‐dose administration of CBE. CBE prepared in methanol was orally administered in a dose of 500 mg/kg/day to female rats during day 1–7 of gestation. Routine H&E histology of uteri was studied during estrus phase and days 4–7 of gestation. The vascular endothelial growth factor (VEGF‐C) was studied immunohistochemically and via western blot using VEGF‐C antibody.

Results

The crude bark extract induced the structural aberration of uterine histology in cyclic stage and during peri‐implantation. Cellular degeneration of embryo and supporting maternal tissue caused loss of embryo minimizing the litter size. Expression of VEGF‐C was drastically reduced in the CBE treated females’ uteri than that of the controls.

Conclusions

CBE contains potential compounds capable of fertility control as post‐coital contraceptive. Effects of CBE on embryo and foetal‐maternal interface either mediated through reduced VEGF‐C expression or vice versa.
Longitudinal measures of proteostasis in live neurons: Features that determine fate in models of neurodegenerative disease
Authors: Skibinski Gaia , Finkbeiner Steven
Published: March 2013

Protein misfolding and proteostasis decline is a common feature of many neurodegenerative diseases. However, modeling the complexity of proteostasis and the global cellular consequences of its disruption is a challenge, particularly in live neurons. Although conventional approaches, based on population measures and single “snapshots”, can identify cellular changes during neurodegeneration, they fail to determine if these cellular events drive cell death or act as adaptive responses. Alternatively, a “systems” cell biology approach known as longitudinal survival analysis enables single neurons to be followed over the course of neurodegeneration. By capturing the dynamics of misfolded proteins and the multiple cellular events that occur along the way, the relationship of these events to each other and their importance and role during cell death can be determined. Quantitative models of proteostasis dysfunction may yield unique insight and novel therapeutic strategies for neurodegenerative disease.
An alternative view of generalized Lagrangian mean theory
Authors: Salmon Rick
Published: March 2013

If the variables describing wave–mean flow interactions are chosen to include a set of fluid–particle labels corresponding to the mean flow, then the generalized Lagrangian mean (GLM) theory takes the form of an ordinary classical field theory. Its only truly distinctive features then arise from the distinctive feature of fluid dynamicsas a field theory, namely, the particle-relabelling symmetry property, which corresponds by Noether’s theorem to the many vorticity conservation laws of fluid mechanics. The key feature of the formulation is thatallthe dependent variables depend on a common set of space–time coordinates. This feature permits an easy and transparent derivation of the GLM equations by use of the energy–momentum tensor formalism. The particle-relabelling symmetry property leads to the GLM potential vorticity law in which pseudo-momentum is the only wave activity term present. Thus the particle-relabelling symmetry explains the prominent importance of pseudo-momentum in GLM theory.
Stationary plume induced by carbon dioxide dissolution
Authors: Nadal F. , Meunier P. , Pouligny B. , Laurichesse E.
Published: March 2013

In this paper, laminar convection flows induced by carbon dioxide absorption are addressed from experimental, numerical and theoretical points of view. A vertical glass tube (of centimetre scale) filled with distilled water is subjected to a sudden increase in the partial pressure of carbon dioxide. As a result of the diffusion of the gas into the unsaturated solution, a thin layer of fluid located underneath the surface becomes heavier. This initial density gradient first destabilizes to form a plume, which goes downwards through the entire cell. After a first transient pulsating regime (periodic succession of such Rayleigh–Bénard plumes), a stationary flow settles in the tube, which is maintained by the constant supply of gas at the surface. At late stages, this stationary regime is followed by an aperiodic regime, which lasts until the complete saturation of the solution (thermodynamic equilibrium). The present study only focuses on the stationary regime, whose characteristics appear to be almost independent of the Bond number and the aspect ratio but strongly dependent on the chemical Rayleigh number. Three decades of Rayleigh numbers are explored using particle image velocimetry measurements, which allows for a precise determination of the scaling exponents for the vertical velocity amplitude and the plume width. The assumption that gravity and a constant pressure gradient balance the viscous effects enables us to derive an analytic expression for the stationary vertical velocity on the axis, which scales as ${\mathit{Ra}}^{2/ 3} \mathop{(\ln \mathit{Ra})}\nolimits ^{1/ 3} $. As a consequence, the width of the plume scales as ${\mathit{Ra}}^{- 1/ 6} \mathop{(\ln \mathit{Ra})}\nolimits ^{- 1/ 3} $ and the mass Nusselt number as $\mathop{(\mathit{Ra}/ \ln \mathit{Ra})}\nolimits ^{1/ 3} $. These scalings are in excellent agreement with the experimental and numerical results. The multiplicative constants of these scalings can also be calculated and show a fairly good agreement if a rigid boundary condition (no-slip) is assumed at the free surface.
The shape stability of a lipid vesicle in a uniaxial extensional flow
Authors: Zhao Hong , Shaqfeh Eric S. G.
Published: March 2013

The dynamics of a lipid vesicle in a uniaxial extensional flow are investigated by using a spectral boundary integral equation method. The vesicle at its stationary state assumes an axisymmetric shape of mirror symmetry, with its surface velocity vanishing everywhere. When the reduced volume of the vesicle is less than 0.75, there exists a critical capillary number, beyond which the stationary shape is unstable. The most unstable mode breaks the mirror symmetry of the shape so that the vesicle deforms into a dumbbell shape with two unequally sized ends. This is followed by the formation of a thin tube bridging the two dumbbell ends, whose length increases with time. The numerical results are in qualitative agreement with experimental observations.
Flow over a flat plate with uniform inlet and incident coherent gusts
Authors: Afgan Imran , Benhamadouche Sofiane , Han Xingsi , Sagaut Pierre , Laurence Dominique
Published: March 2013

The flow over a flat plate at a Reynolds number of 750 is numerically investigated via fine large-eddy simulation (LES), first at normal ($90\textdegree $) and then at oblique ($45\textdegree $) incidence flow direction with a uniform steady inlet. The results are in complete agreement with the direct numerical simulation (DNS) and experimental data, thereby serving as a validation for the present simulations. For the normal ($90\textdegree $) uniform inflow case, coherent vortices are alternately shed from both leading edges of the plate, whereas for the oblique ($45\textdegree $) uniform inflow case the vortices shed from the two sides of the plate interact strongly resulting in a quasi-periodic force response. The normal flat plate is then analysed with an incident gust signal with varying amplitude and time period. For these incident coherent gust cases, a reference test case with variable coherent inlet is first studied and the results are compared to a steady inlet simulation, with a detailed analysis of the flow behaviour and the wake response under the incident gust. Finally, the flat plate response to 16 different gust profiles is studied. A transient drag reconstruction for these incident coherent gust cases is then presented based on a frequency-dependent transfer function and phase spectrum analysis.
Lift and the leading-edge vortex
Authors: Pitt Ford C. W. , Babinsky H.
Published: March 2013

Flapping wings often feature a leading-edge vortex (LEV) that is thought to enhance the lift generated by the wing. Here the lift on a wing featuring a leading-edge vortex is considered by performing experiments on a translating flat-plate aerofoil that is accelerated from rest in a water towing tank at a fixed angle of attack of 15°. The unsteady flow is investigated with dye flow visualization, particle image velocimetry (PIV) and force measurements. Leading- and trailing-edge vortex circulation and position are calculated directly from the velocity vectors obtained using PIV. In order to determine the most appropriate value of bound circulation, a two-dimensional potential flow model is employed and flow fields are calculated for a range of values of bound circulation. In this way, the value of bound circulation is selected to give the best fit between the experimental velocity field and the potential flow field. Early in the trajectory, the value of bound circulation calculated using this potential flow method is in accordance with Kelvin’s circulation theorem, but differs from the values predicted by Wagner’s growth of bound circulation and the Kutta condition. Later the Kutta condition is established but the bound circulation remains small; most of the circulation is contained instead in the LEVs. The growth of wake circulation can be approximated by Wagner’s circulation curve. Superimposing the non-circulatory lift, approximated from the potential flow model, and Wagner’s lift curve gives a first-order approximation of the measured lift. Lift is generated by inertial effects and the slow buildup of circulation, which is contained in shed vortices rather than bound circulation.
Structural sensitivity of spiral vortex breakdown
Authors: Qadri Ubaid Ali , Mistry Dhiren , Juniper Matthew P.
Published: March 2013

Previous numerical simulations have shown that vortex breakdown starts with the formation of a steady axisymmetric bubble and that an unsteady spiralling mode then develops on top of this. We investigate this spiral mode with a linear global stability analysis around the steady bubble and its wake. We obtain the linear direct and adjoint global modes of the linearized Navier–Stokes equations and overlap these to obtain the structural sensitivity of the spiral mode, which identifies the wavemaker region. We also identify regions of absolute instability with a local stability analysis. At moderate swirls, we find that the $m= - 1$ azimuthal mode is the most unstable and that the wavemaker regions of the $m= - 1$ mode lie around the bubble, which is absolutely unstable. The mode is most sensitive to feedback involving the radial and azimuthal components of momentum in the region just upstream of the bubble. To a lesser extent, the mode is also sensitive to feedback involving the axial component of momentum in regions of high shear around the bubble. At an intermediate swirl, in which the bubble and wake have similar absolute growth rates, other researchers have found that the wavemaker of the nonlinear global mode lies in the wake. We agree with their analysis but find that the regions around the bubble are more influential than the wake in determining the growth rate and frequency of the linear global mode. The results from this paper provide the first steps towards passive control strategies for spiral vortex breakdown.
Capillary-wave scattering from an infinitesimal barrier and dissipation at dynamic contact lines
Authors: Zhang Likun , Thiessen David B.
Published: March 2013

The interaction of pure capillary waves with boundaries that constrain the contact line are of interest for problems involving liquids contained by minimal solid contact for applications in low gravity and at small scales in normal gravity. Time-harmonic capillary waves on a liquid cylinder axially incident on and scattered by an infinitesimal concentric barrier are considered theoretically in the inviscid limit. The barrier is taken to be infinitesimally small in the sense that its immersed depth is of the order of the amplitude of contact-line motion. Edge conditions on the barrier that are investigated include a pinned contact line and a moving contact line by an effective-slip model, assuming that contact-line velocity is proportional to the deviation of the contact angle from equilibrium multiplied by a slip coefficient. The incident waves are taken to be those with wavelengths short enough to be stable on the liquid cylinder. Scattering and dissipation by the contact line are determined as a function of wavenumber and slip coefficient. Zero transmission is approached in the long-wave limit. The short-wave limit agrees with established results for the scattering of planar gravity–capillary waves on a deep liquid by a surface-piercing vertical barrier in the limit of zero barrier depth and zero gravity. We find that contact-line dissipation at the barrier is a maximum for incident waves whose phase speed is of the order of the slip coefficient, which is interpreted as an effect of impedance matching. Transmission past an infinitesimal barrier is found to be low over all parameter space, illustrating the importance of contact-line constraints.
Stratified precessional flow in spherical geometry
Authors: Wei Xing , Tilgner Andreas
Published: February 2013

We investigate numerically, in spherical geometry, the interaction of stratification with precession. Both stable stratification and unstable stratification are studied. In the parameter regime we are concerned with, stable stratification suppresses the precessional instability, whereas unstable stratification and precession can either stabilize or destabilize each other at different precession rates.
Variability in glutenin subunit composition of Mediterranean durum wheat germplasm and its relationship with gluten strength
Authors: NAZCO R. , PEÑA R. J. , AMMAR K. , VILLEGAS D. , CROSSA J. , MORAGUES M. , ROYO C.
Published: March 2013

The allelic composition at five glutenin loci was assessed by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (1D SDS–PAGE) on a set of 155 landraces (from 21 Mediterranean countries) and 18 representative modern varieties. Gluten strength was determined by SDS-sedimentation on samples grown under rainfed conditions during 3 years in north-eastern Spain. One hundred and fourteen alleles/banding patterns were identified (25 at Glu-1 and 89 at Glu-2/Glu-3 loci); 0·85 of them were in landraces at very low frequency and 0·72 were unreported. Genetic diversity index was 0·71 for landraces and 0·38 for modern varieties. All modern varieties exhibited medium to strong gluten type with none of their 13 banding patterns having a significant effect on gluten-strength type. Ten banding patterns significantly affected gluten strength in landraces. Alleles Glu-B1e (band 20), Glu-A3a (band 6), Glu-A3d (bands 6 + 11), Glu-B3a (bands 2 + 4+15 + 19) and Glu-B2a (band 12) significantly increased the SDS-value, and their effects were associated with their frequency. Two alleles, Glu-A3b (band 5) and Glu-B2b (null), significantly reduced gluten strength, but only the effect of the latter locus could be associated with its frequency. Only three rare banding patterns affected gluten strength significantly: Glu-B1a (band 7), found in six landraces, had a negative effect, whereas banding patterns 2 + 4+14 + 15 + 18 and 2 + 4+15 + 18 + 19 at Glu-B3 had a positive effect. Landraces with outstanding gluten strength were more frequent in eastern than in western Mediterranean countries. The geographical pattern displayed from the frequencies of Glu-A1c is discussed.
Speculative Retail Trading and Asset Prices
Authors: Han Bing , Kumar Alok
Published: March 2013

This paper examines the characteristics and pricing of stocks that are actively traded by speculative retail investors. We find that stocks with high retail trading proportion (RTP) have strong lottery features and they attract retail investors with strong gambling propensity. Furthermore, these stocks tend to be overpriced and earn significantly negative alpha. The average monthly return differential between the extreme RTP quintiles is −0.60%. This negative RTP premium is stronger among stocks that have lottery features or arelocated in regions where people exhibit stronger gambling propensity. Collectively, these results indicate that speculative retail trading affects stock prices.
THz generation by the beating of two high intense laser beams
Authors: NAFIL RABEA Q. , SINGH MONIKA , AL-JANABI A. H. , SHARMA R. P.
Published: March 2013

The nonlinear coupling of two high-power laser beams in plasmas in the presence of a transverse, static electric field is investigated to generate a difference frequency terahertz (THz) radiation. The relativistic variation of electron mass in the presence of two high-power laser beams is responsible for producing a nonlinear current driving the THz radiation. For typical laser and plasma parameters, we report the efficiency of the order of ~10−4 for the current scheme.
Mucosal trapping and degradation of Nippostrongylus brasiliensis occurs in the absence of STAT6
Authors: VAN PANHUYS NICHOLAS , CAMBERIS MALI , YAMADA MINORU , TEGOSHI TATSUYA , ARIZONO NAOKI , LE GROS GRAHAM
Published: February 2013

Hookworms represent a major infectious burden globally, especially in developing countries. The murine hookworm Nippostrongylus brasiliensis is normally cleared in a manner dependent on IL-13, IL4-R and STAT6 signalling. Here we have used STAT6-deficient animals to model a non-resistant population and describe 2 novel STAT6-independent processes for the clearance of N. brasiliensis. During primary infection STAT6−/− animals are able to clear gut-dwelling N. brasiliensis by a mechanism involving the trapping and degradation of worms in the gut mucosa. Here, a previously undescribed STAT6-independent up-regulation of Relm-β was observed which correlated with the mucosal trapping and degradation of worms. Previous studies have indicated that during secondary infection STAT6 deficient animals fail to expel adult worms and remain susceptible to re-infection and long-term colonization of the gut. We report here that an initial partially protective response occurs early upon re-infection in the absence of STAT6, and that a late-phase protective secondary response arises in the gut of STAT6-deficient mice leading to the clearance of the majority of N. brasiliensis, through their trapping and death in the mucosal layer of the lower region of the small intestine. These findings show that there are a number of redundant effector pathways which act to reduce worm burden in the gut which can be activated by mechanisms that do not work through the dominant STAT6 signalling pathway and may be useful as targets for future vaccination strategies against resistant hookworm strains.
“Qu'es-tu venu faire icy?”: French Galibí Relations in Guiana, 1640–1665
Authors: Brunelle Gayle K.
Published: February 2013

After failing to wrest Brazil from the Portuguese in the sixteenth century, the French turned their attention to the region north of the Amazon and south of the Orinoco River. The Guiana ventures the French launched during the middle decades of the seventeenth century met with numerous disasters, many of them self-inflicted, including bankruptcies, mutinies, murder, and costly rivalries between companies based in Paris and Rouen. Despite their many setbacks during the seventeenth century, however, the French were determined to establish plantations on the island of Cayenne in modern French Guiana. By the eighteenth century, French planters were cultivating sugar and tobacco in and around Cayenne using primarily the labour of African slaves. The nucleus, thus, of the future colony of French Guiana had been laid, in a territory sandwiched between the English colony of Guyana and the Dutch colony of Suriname, to the northwest, and Portuguese-controlled territory to the south and east. Prospering in Guiana was never easy, for the French or their African slaves, as the 1762–4 disaster of Kourou attests. But by then, the indigenous Galibí inhabitants of Cayenne (members of the Carib language group) seem to have been largely “written out” of the history of Guiana, except when they appear as a minority of slaves among a sea of Africans on a plantation.