bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Overfeeding on Spontaneous Physical Activity in Obesity Prone and Obesity Resistant Humans
Authors: Schmidt Stacy L. , Harmon Kristin A. , Sharp Teresa A. , Kealey Elizabeth H. , Bessesen Daniel H.
Published: April 2012

Despite living in an environment that promotes weight gain in many individuals, some individuals maintain a thin phenotype while self‐reporting expending little or no effort to control their weight. When compared with obesity prone (OP) individuals, we wondered if obesity resistant (OR) individuals would have higher levels of spontaneous physical activity (SPA) or respond to short‐term overfeeding by increasing their level of SPA in a manner that could potentially limit future weight gain. SPA was measured in 55 subjects (23 OP and 32 OR) using a novel physical activity monitoring system (PAMS) that measured body position and movement while subjects were awake for 6 days, either in a controlled eucaloric condition or during 3 days of overfeeding (1.4× basal energy) and for the subsequent 3 days (ad libitum recovery period). Pedometers were also used before and during use of the PAMS to provide an independent measure of SPA. SPA was quantified by the PAMS as fraction of recording time spent lying, sitting, or in an upright posture. Accelerometry, measured while subjects were in an upright posture, was used to categorize time spent in different levels of movement (standing, walking slowly, quickly, etc.). There were no differences in SPA between groups when examined across all study periods (P > 0.05). However, 3 days following overfeeding, OP subjects significantly decreased the amount of time they spent walking (−2.0% of time, P = 0.03), whereas OR subjects maintained their walking (+0.2%, P > 0.05). The principle findings of this study are that increased levels of SPA either during eucaloric feeding or following short term overfeeding likely do not significantly contribute to obesity resistance although a decrease in SPA following overfeeding may contribute to future weight gain in individuals prone to obesity.
Short‐Term Lenalidomide (Revlimid) Administration Ameliorates Cardiomyocyte Contractile Dysfunction in ob/ob Obese Mice
Authors: Li Linlin , Hua Yinan , Dong Maolong , Li Quan , Smith Derek T. , Yuan Ming , Jones Kyla R. , Ren Jun
Published: April 2012

Lenalidomide is a potent immunomodulatory agent capable of downregulating proinflammatory cytokines such as tumor necrosis factor‐α (TNF‐α) and upregulating anti‐inflammatory cytokines. Lenalidomide has been shown to elicit cardiovascular effects, although its impact on cardiac function remains obscure. This study was designed to examine the effect of lenalidomide on cardiac contractile function in ob/ob obese mice. C57BL lean and ob/ob obese mice were given lenalidomide (50 mg/kg/day, p.o.) for 3 days. Body fat composition was assessed by dual‐energy X‐ray absorptiometry. Cardiomyocyte contractile and intracellular Ca2+ properties were evaluated. Expression of TNF‐α, interleukin‐6 (IL‐6), Fas, Fas ligand (FasL), the short‐chain fatty acid receptor GPR41, the NFκB regulator IκB, endoplasmic reticulum (ER) stress, the apoptotic protein markers Bax, Bcl‐2, caspase‐8, tBid, cytosolic cytochrome C, and caspase‐12; and the stress signaling molecules p38 and extracellular signal‐regulated kinase (ERK) were evaluated by western blot. ob/ob mice displayed elevated serum TNF‐α and IL‐6 levels, fat composition and glucose intolerance, the effects of which except glucose intolerance and fat composition were attenuated by lenalidomide. Cardiomyocytes from ob/ob mice exhibited depressed peak shortening (PS) and maximal velocity of shortening/relengthening, prolonged time‐to‐PS and time‐to‐90% relengthening as well as intracellular Ca2+ mishandling, which were ablated by lenalidomide. Western blot analysis revealed elevated levels of TNF‐α, IL‐6, Fas, Bip, Bax, caspase‐8, tBid, cleaved caspase‐3 caspase‐12, cytochrome C, phosphorylation of p38, and ERK in ob/ob mouse hearts, the effects of which with the exception of Bip, Bax, and caspase‐12 were alleviated by lenalidomide. Taken together, these data suggest that lenalidomide is protective against obesity‐induced cardiomyopathy possibly through antagonism of cytokine/Fas‐induced activation of stress signaling and apoptosis.
Upregulation of Plasma Insulin‐Like Growth Factor Binding Protein 2 Levels After Biliopancreatic Diversion in Humans
Authors: Li Zhuo , Martin Julie , Poirier Paul , Caron‐Cantin Sarah‐Maude , Hould Frédéric‐Simon , Marceau Simon , Marceau Picard , Picard Frédéric
Published: April 2012

The biliopancreatic diversion surgery with duodenal switch (BPD‐DS) is a surgical procedure that not only induces significant weight loss, but also promotes remission of diabetes. However, the mechanism responsible for this insulin‐potentiating effect (both on sensitivity and production) is not yet clearly understood. The insulin‐like growth factor (IGF) binding protein 2 (IGFBP‐2) is a 36 kDa circulating protein that has been recently suggested to modulate insulin sensitization and fat accumulation. In humans, a low‐circulating concentration of IGFBP‐2 has been associated with obesity and insulin resistance. We thus tested the hypothesis that BPD‐DS would trigger an increase in IGFBP‐2 levels. Plasma IGFBP‐2 was quantified by enzyme‐linked immunosorbent assay in 77 severely obese men and women before and up to 1 year after BPD‐DS surgery. Baseline IGFBP‐2 levels were 159 ± 17 ng/ml. Plasma IGFBP‐2 levels increased significantly as soon as 24 h after BPD‐DS surgery and were further augmented at both 6 months and 1 year after the surgery, reaching 748 ± 65 ng/ml. Changes in IGFBP‐2 concentrations were significantly and negatively associated with blood glucose, insulin, triglycerides, and total cholesterol levels. The present findings suggest that the rise in IGFBP‐2 levels is associated with the improvements in glucose and lipid metabolism in the short‐ and long‐term after BPD‐DS. The mechanisms for the augmentation in IGFBP‐2 after BPD‐DS and its contribution to insulin sensitization remain to be elucidated.
Effective Approaches to International Work: Substance and Sustainability for Speech-Language Pathology Student Groups
Authors: Crowley Catherine (Cate) , Baigorri Miriam
Published: April 2012

International opportunities for speech language pathologists and audiologists are on the rise. Opportunities range from single trips offering clinical services to long-term commitments including developing speech-language treatment programs in developing countries. This article provides a brief overview of the types of international programs available. It then focuses on international opportunities for speech-language pathology students with a particular focus on the authors' international programs in Bolivia and Ghana.
Bennett's acceptance ratio and histogram analysis methods enhanced by umbrella sampling along a reaction coordinate in configurational space
Authors: Kim Ilsoo , Allen Toby W.
Published: April 2012

Free energy perturbation, a method for computing the free energy difference between two states, is often combined with non-Boltzmann biased sampling techniques in order to accelerate the convergence of free energy calculations. Here we present a new extension of the Bennett acceptance ratio (BAR) method by combining it with umbrella sampling (US) along a reaction coordinate in configurational space. In this approach, which we call Bennett acceptance ratio with umbrella sampling (BAR-US), the conditional histogram of energy difference (a mapping of the 3N-dimensional configurational space via a reaction coordinate onto 1D energy difference space) is weighted for marginalization with the associated population density along a reaction coordinate computed by US. This procedure produces marginal histograms of energy difference, from forward and backward simulations, with higher overlap in energy difference space, rendering free energy difference estimations using BAR statistically more reliable. In addition to BAR-US, two histogram analysis methods, termed Bennett overlapping histograms with US (BOH-US) and Bennett-Hummer (linear) least square with US (BHLS-US), are employed as consistency and convergence checks for free energy difference estimation by BAR-US. The proposed methods (BAR-US, BOH-US, and BHLS-US) are applied to a 1-dimensional asymmetric model potential, as has been used previously to test free energy calculations from non-equilibrium processes. We then consider the more stringent test of a 1-dimensional strongly (but linearly) shifted harmonic oscillator, which exhibits no overlap between two states when sampled using unbiased Brownian dynamics. We find that the efficiency of the proposed methods is enhanced over the original Bennett's methods (BAR, BOH, and BHLS) through fast uniform sampling of energy difference space via US in configurational space. We apply the proposed methods to the calculation of the electrostatic contribution to the absolute solvation free energy (excess chemical potential) of water. We then address the controversial issue of ion selectivity in the K+ ion channel, KcsA. We have calculated the relative binding affinity of K+ over Na+ within a binding site of the KcsA channel for which different, though adjacent, K+ and Na+ configurations exist, ideally suited to these US-enhanced methods. Our studies demonstrate that the significant improvements in free energy calculations obtained using the proposed methods can have serious consequences for elucidating biological mechanisms and for the interpretation of experimental data.
A numerical investigation of the fluid mechanical sewing machine
Authors: Brun P.-T. , Ribe N. M. , Audoly B.
Published: April 2012

A thin thread of viscous fluid falling onto a moving belt generates a surprising variety of patterns depending on the belt speed, fall height, flow rate, and fluid properties. Here, we simulate this experiment numerically using the discrete viscous threads method that can predict the non-steady dynamics of thin viscous filaments, capturing the combined effects of inertia and of deformation by stretching, bending, and twisting. Our simulations successfully reproduce nine out of ten different patterns previously seen in the laboratory and agree closely with the experimental phase diagram of Morris et al. [Phys. Rev. E 77, 066218 (2008)]10.1103/PhysRevE.77.066218. We propose a new classification of the patterns based on the Fourier spectra of the longitudinal and transverse motion of the point of contact of the thread with the belt. These frequencies appear to be locked in most cases to simple ratios of the frequency Ωc of steady coiling obtained in the limit of zero belt speed. In particular, the intriguing “alternating loops” pattern is produced by combining the first five multiples of Ωc/3.
Effect of swirl decay on vortex breakdown in a confined steady axisymmetric flow
Authors: Shtern Vladimir N. , del Mar Torregrosa María , Herrada Miguel A.
Published: April 2012

This numerical study of the steady axisymmetric motion of a viscous incompressible fluid in a sealed cylindrical container with one end wall rotating reveals that swirl decay, induced by friction at the sidewall, plays an important role in the development of vortex breakdown (VB). When the flow is slow, it is multi-cellular. As the flow strength increases (i) meridional circulation becomes global, (ii) flow convergence toward the axis focuses near the still end wall, (iii) a few local minima of pressure appear, (iv) a few flow reversals occur near the axis, and (v) circulation regions merge and an elongated double counterflow develops. Stages (i)–(v) are common for a number of vortex devices. If the swirl decay is diminished by additional rotation of the sidewall, VB disappears.
Shock compression response of α″-Fe16N2 nanoparticles
Authors: Wehrenberg Christopher , Zande Brian , Simizu Satoru , Obermyer R. T. , Sankar S. G. , Thadhani Naresh
Published: April 2012

The shock compression response of α''-Fe16N2 nanoparticles is studied in order to evaluate the thermo-mechanical stability of the α'' phase under shock loading. Shock compression experiments were performed using the parallel plate impact gas gun set up at velocities near 850 m/s. The experiments were performed at −21 °C and −126 °C in order to minimize temperature excursions and thereby determine the thermal effects on the phase stability. The α''-Fe16N2 phase is observed to partially decompose into α-Fe and γ'-Fe4N in both samples, as detected by the XRD analysis. The lower temperature produces a higher percentage of γ' phase in addition to the γ''-Fe50N50 phase. The pressure-volume-temperature response of the material is modeled using the dynamic mechanical properties of high nitrogen steel. The model is then used to evaluate the temperature excursions and their effect on the phase transitions observed.
Tunable optical tweezers for wavelength-dependent measurements
Authors: Hester Brooke , Campbell Gretchen K. , López-Mariscal Carlos , Filgueira Carly Levin , Huschka Ryan , Halas Naomi J. , Helmerson Kristian
Published: April 2012

Optical trapping forces depend on the difference between the trap wavelength and the extinction resonances of trapped particles. This leads to a wavelength-dependent trapping force, which should allow for the optimization of optical tweezers systems, simply by choosing the best trapping wavelength for a given application. Here we present an optical tweezer system with wavelength tunability, for the study of resonance effects. With this system, the optical trap stiffness is measured for single trapped particles that exhibit either single or multiple extinction resonances. We include discussions of wavelength-dependent effects, such as changes in temperature, and how to measure them.
Self consistent measurement and removal of the dipolar interaction field in magnetic particle assemblies and the determination of their intrinsic switching field distribution
Authors: Martínez Huerta J. M. , De La Torre Medina J. , Piraux L. , Encinas A.
Published: April 2012

Using low density arrays of bistable magnetic nanowires as a model dipolar system, it is shown that the dipolar interaction field coefficient can be measured from the remanence curves as well as from other functions of the isothermal remanent magnetization and the DC demagnetization remanence obtained as an affine transformation of the Wohlfarth relation. Based on mean field arguments, these measurements are used to subtract and remove the contribution of the configuration dependent dipolar interaction field from the major loop and remanence curves. The corrected remanence curves are first used to obtain the intrinsic switching field distribution of the nanowire array and then to validate this approach showing that they yield results consistent with the Wohlfarth relation for an assembly of noninteracting particles, thus providing a self-consistent procedure to verify the measured values of the interaction field and its removal from the measurements.
Structural recovery of ion implanted ZnO nanowires
Authors: Perillat-Merceroz G. , Donatini F. , Thierry R. , Jouneau P.-H. , Ferret P. , Feuillet G.
Published: April 2012

Ion implantation is an interesting method to dope semiconducting materials such as zinc oxide provided that the implantation-induced defects can be subsequently removed. Nitrogen implantation followed by anneals under O2 were carried out on zinc oxide nanowires in the same conditions as in a previous study on bulk ZnO [Perillat-Merceroz et al., J. Appl. Phys. 109, 023513 (2011)], allowing a direct comparison of the defect recovery mechanisms. Transmission electron microscopy and cathodoluminescence were carried out to assess the effects of nitrogen implantation and of subsequent anneals on the structural and optical properties of ZnO nanowires. Defect recovery is shown to be more effective in nanowires compared with bulk material due to the proximity of free surfaces. Nevertheless, the optical emission of implanted and annealed nanowires deteriorated compared to as-grown nanowires, as also observed for unimplanted and annealed nanowires. This is tentatively attributed to the dissociation of excitons in the space charge region induced by O2 adsorption on the nanowire surface.
Temperature dependent elastic constants for crystals with arbitrary symmetry: Combined first principles and continuum elasticity theory
Authors: Shao Tianjiao , Wen Bin , Melnik Roderick , Yao Shan , Kawazoe Yoshiyuki , Tian Yongjun
Published: April 2012

To study temperature dependent elastic constants, a new computational method is proposed by combining continuum elasticity theory and first principles calculations. A Gibbs free energy function with one variable with respect to strain at given temperature and pressure was derived; hence, the minimization of the Gibbs free energy with respect to temperature and lattice parameters can be put into effective operation by using first principles. Therefore, with this new theory, anisotropic thermal expansion and temperature dependent elastic constants can be obtained for crystals with arbitrary symmetry. In addition, we apply our method to hexagonal beryllium, hexagonal diamond, and cubic diamond to illustrate its general applicability.
Will water act as a photocatalyst for cluster phase chemical reactions? Vibrational overtone-induced dehydration reaction of methanediol
Authors: Kramer Zeb C. , Takahashi Kaito , Vaida Veronica , Skodje Rex T.
Published: April 2012

The possibility of water catalysis in the vibrational overtone-induced dehydration reaction of methanediol is investigated using ab initio dynamical simulations of small methanediol-water clusters. Quantum chemistry calculations employing clusters with one or two water molecules reveal that the barrier to dehydration is lowered by over 20 kcal/mol because of hydrogen-bonding at the transition state. Nevertheless, the simulations of the reaction dynamics following OH-stretch excitation show little catalytic effect of water and, in some cases, even show an anticatalytic effect. The quantum yield for the dehydration reaction exhibits a delayed threshold effect where reaction does not occur until the photon energy is far above the barrier energy. Unlike thermally induced reactions, it is argued that competition between reaction and the irreversible dissipation of photon energy may be expected to raise the dynamical threshold for the reaction above the transition state energy. It is concluded that quantum chemistry calculations showing barrier lowering are not sufficient to infer water catalysis in photochemical reactions, which instead require dynamical modeling.
Drops settling in sharp stratification with and without Marangoni effects
Authors: Blanchette François , Shapiro Avi M.
Published: April 2012

We present numerical simulations of drops settling in a layered ambient fluid. We focus on nearly spherical drops with Reynolds numbers of order 10. The ambient is composed of miscible fluids, with the top layer lighter than the lower one, representing fluid stratified through temperature or salinity variations, while the drop itself is heavier than both layers. The surface tension between the ambient and the drop may or may not be different for each layer. Such a system can be used to model oil droplets settling or rising in the ocean. When surface tension is uniform, the drop slows down significantly as it encounters the transition region, due to entrained fluid from the upper layer, before accelerating again in the lower layer. We characterize this effect in terms of the sharpness of the transition, and the drop's Reynolds number. When the upper and lower surface tensions are not matched, the drop may either suddenly accelerate through the transition region if the lower surface tension is less than the upper one, or be prevented from crossing into the lower layer if the lower surface tension is larger than the upper one. We focus on the drop's speed across the transition, and determine the conditions under which a drop may remain suspended at the transition region.
An improved microfluidics approach for monitoring real-time interaction profiles of ultrafast molecular recognition
Authors: Batabyal Subrata , Rakshit Surajit , Kar Shantimoy , Pal Samir Kumar
Published: April 2012

Our study illustrates the development of a microfluidics (MF) platform combining fluorescence microscopy and femtosecond/picosecond-resolved spectroscopy to investigate ultrafast chemical processes in liquid-phase diffusion-controlled reactions. By controlling the flow rates of two reactants in a specially designed MF chip, sub-100 ns time resolution for the exploration of chemical intermediates of the reaction in the MF channel has been achieved. Our system clearly rules out the possibility of formation of any intermediate reaction product in a so-called fast ionic reaction between sodium hydroxide and phenolphthalein, and reveals a microsecond time scale associated with the formation of the reaction product. We have also used the developed system for the investigation of intermediate states in the molecular recognition of various macromolecular self-assemblies (micelles) and genomic DNA by small organic ligands (Hoechst 33258 and ethidium bromide). We propose our MF-based system to be an alternative to the existing millisecond-resolved “stopped-flow” technique for a broad range of time-resolved (sub-100 ns to minutes) experiments on complex chemical/biological systems.
Eu luminescence center created by Mg codoping in Eu-doped GaN
Authors: Lee Dong-gun , Nishikawa Atsushi , Terai Yoshikazu , Fujiwara Yasufumi
Published: April 2012

We investigated the photoluminescence properties of Eu,Mg-codoped GaN grown by organometallic vapor phase epitaxy. Some emission due to intra-4f shell transition of 5D0-7F2 in Eu3+ ions in a center with Eu and Mg was observed together with typical Eu emission. The peak intensity of the Eu-Mg emission was about five times higher than that of the typical Eu emission. The Eu-Mg emission exhibited a maximum at around 180 K, while the typical Eu emission intensity decreased monotonically with increasing temperature. It was found that only one type of Eu-Mg center contributed to the enhanced intensity up to 180 K.
Precise and programmable manipulation of microbubbles by two-dimensional standing surface acoustic waves
Authors: Meng Long , Cai Feiyan , Chen Juanjuan , Niu Lili , Li Yanming , Wu Junru , Zheng Hairong
Published: April 2012

A microfluidic device is developed to transport microbubbles (MBs) along a desired trajectory in fluid by introducing the phase-shift to a planar standing surface acoustic wave (SSAW). The radiation force of SSAW due to the acoustic pressure gradient modulated by a phase-shift can move MBs to anticipated potential wells in a programmable manner. The resolution of the transportation is approximately 2.2 µm and the estimated radiation force on the MBs is on the order of 10−9 N. This device can be used for manipulation of bioparticles, cell sorting, tissue engineering, and other biomedical applications.
Strain relaxation by dislocation glide in ZnO/ZnMgO core-shell nanowires
Authors: Perillat-Merceroz G. , Thierry R. , Jouneau P.-H. , Ferret P. , Feuillet G.
Published: April 2012

Plastic relaxation of the misfit stress in core-shell semi-conducting nanowires can lead to structural defects, detrimental to applications. Core-shell Zn0.7Mg0.3O/ZnO quantum well heterostructures were deposited on ZnO nanowires. Strain along the a and c axes of the wurtzite structure is relaxed through the glide of dislocation half-loops from the free surfaces, within pyramidal and prismatic planes. Some half-loops are closed up in the barriers to accommodate the misfit at two consecutive interfaces of the quantum well stack. Dislocations are also observed within the nanowire core: contrary to two-dimensional structures, both the core and the shell can be plastically relaxed.
Effect of doping concentration of substrate silicon on retention characteristics in metal-ferroelectric-insulator-semiconductor capacitors
Authors: Xiao Y. G. , Xiong Y. , Tang M. H. , Li J. C. , Cheng C. P. , Jiang B. , Tang Z. H. , Lv X. S. , Cai H. Q. , Gu X. C. , Zhou Y. C.
Published: April 2012

The polarization retention characteristics in metal-ferroelectric-insulator-semiconductor (MFIS) capacitor was theoretically investigated by considering depolarization field based on Lou’s polarization retention model [J. Appl. Phys. 105(9), 094107 (2009)]. The derived results demonstrated that the retention property can be effectively improved by enhancing the doping concentration of substrate silicon. Additionally, it is better to keep the MFIS capacitor at accumulation and depletion regions than at inversion region for improving the polarization retention property. It is expected that this investigation may offer some useful guidelines to the design and retention property improvement of MFIS capacitor and other MFIS structure devices.
Enhancement of Raman scattering by field superposition of rough submicrometer silver particles
Authors: Zhang Feng , Chen Ping , Zhang Lei , Mao Song-Cheng , Lin Lie , Tang Yu-Guo , Cui Ji-Cheng , Qi Xiang-Dong , Yang Jun-Hong , Ma Yun-Feng
Published: April 2012

Wavelength-dependent surface-enhanced Raman spectra of methylene blue adsorbed on rough submicrometer silver particles were measured. Results revealed a high enhancement factor (105 ∼ 107), especially in the long-wavelength region. Investigation on the far- and near-field optical properties of the particles showed a remarkably enhanced dipole plasmon resonance due to the presence of a rough particle surface. Through analyzing the plasmon resonance modes and the superposition of radiation fields, we found that the rough surface-induced field superposition results in the redistribution of optical fields around the particle, which becomes a key factor responsible for the high enhancement effect of metal particles.
“Quorum sensing” generated multistability and chaos in a synthetic genetic oscillator
Authors: Potapov I. , Zhurov B. , Volkov E.
Published: April 2012

We model the dynamics of the synthetic genetic oscillator Repressilator equipped with quorum sensing. In addition to a circuit of 3 genes repressing each other in a unidirectional manner, the model includes a phase-repulsive type of the coupling module implemented as the production of a small diffusive molecule—autoinducer (AI). We show that the autoinducer (which stimulates the transcription of a target gene) is responsible for the disappearance of the limit cycle (LC) through the infinite period bifurcation and the formation of a stable steady state (SSS) for sufficiently large values of the transcription rate. We found conditions for hysteresis between the limit cycle and the stable steady state. The parameters’ region of the hysteresis is determined by the mRNA to protein lifetime ratio and by the level of transcription-stimulating activity of the AI. In addition to hysteresis, increasing AI-dependent stimulation of transcription may lead to the complex dynamic behavior which is characterized by the appearance of several branches on the bifurcation continuation, containing different regular limit cycles, as well as a chaotic regime. The multistability which is manifested as the coexistence between the stable steady state, limit cycles, and chaos seems to be a novel type of the dynamics for the ring oscillator with the added quorum sensing positive feedback.
Relaxation of a metallic glass to the metastable equilibrium: Evidence for the existence of the Kauzmann pseudocritical temperature
Authors: Mitrofanov Yu. P. , Khonik V. A. , Granato A. V. , Joncich D. M. , Khonik S. V. , Khoviv A. M.
Published: April 2012

High-precision isothermal measurements on strongly preannealed metallic glass reveal a decrease of the shear modulus to the metastable equilibrium value both in the glassy state far below the glass transition and in the supercooled liquid state near Tg. The results obtained point out the existence of a low-temperature limit for the supercooled liquid, which is known as the Kauzmann pseudocritical temperature [W. Kauzmann, Chem. Rev. 43, 219 (1948)]. This finding experimentally questions the existence of the “Kauzmann paradox,” which is widely discussed in the literature.
Polarization rotation under two-photon Raman resonance for magnetometry
Authors: Pradhan S. , Behera R. , Das A. K.
Published: April 2012

The polarization rotation and coherent population trapping signal arising due to two photon process using linearly polarized light are found to be significantly enhanced for a Zeeman degenerate system. The zero crossing of the dispersive profile is found to be shifting proportional to the applied magnetic field, albeit the absorptive profile position remains invariant for a slightly imbalanced orthogonal circular polarization component. It provides an alternative method for precise measurement of vector magnetic field without requirement of a bias field. The use of polarization rotation signal for magnetic field measurement offers added advantage due to improved signal to noise ratio.
Influence of work-function of top electrodes on the photovoltaic characteristics of Pb0.95La0.05Zr0.54Ti0.46O3 thin film capacitors
Authors: Harshan V. N. , Kotru Sushma
Published: April 2012

Photovoltaic properties of Pb0.95La0.05Zr0.54Ti0.46O3 thin film capacitors prepared using solution based method with metal top electrodes having different work functions are investigated in this work. It is shown that by using aluminum, a low work-function metal, as top electrode, the magnitude of photo voltage as well as photo current can be enhanced. More than one magnitude enhancement in the photovoltaic efficiency is observed with Al as top electrode compared to Pt electrodes. This work clearly highlights that an appropriate choice of low work function metal electrode can enhance the photovoltaic response of the ferroelectric thin film capacitors.
Identification of polymer stabilized blue-phase liquid crystal display by chromaticity diagram
Authors: Lan Yi-Fen , Tsai Cheng-Yeh , Wang Ling-Yung , Ku Po-Jen , Huang Tai-Hsiang , Liu Chu-Yu , Sugiura Norio
Published: April 2012

We reported an identification method of blue phase liquid crystal (BPLC) display status by using Commission International de l’Éclairage (CIE) chromaticity diagram. The BPLC was injected into in-plane-switch (IPS) cell, polymer stabilized (PS) by ultraviolet cured process and analyzed by luminance colorimeter. The results of CIE chromaticity diagram showed a remarkable turning point when polymer stabilized blue phase liquid crystal II (PSBPLC-II) formed in the IPS cell. A mechanism of CIE chromaticity diagram identify PSBPLC display status was proposed, and we believe this finding will be useful to application and production of PSBPLC display.
Density functional investigations on electronic structures, magnetic ordering and ferroelectric phase transition in multiferroic Bi2NiMnO6
Authors: Zhao Hong Jian , Liu Xiao Qiang , Chen Xiang Ming
Published: April 2012

Using the full-potential linearised augmented-plane wave (FP-LAPW) method based on density functional theory (DFT), we have investigated the electronic structures, the magnetic behavior, and the ferroelectric origin of multiferroic Bi2NiMnO6. The calculated ferromagnetic Curie temperature of Bi2NiMnO6 is very sensitive to the Mn4+—O2-—Ni2+ length. When average Mn4+—O2-—Ni2+ length increases from 3.82 to 4.05 Å, the Curie temperature increases from 179 to 295 K. The Mn4+—O2-—Ni2+ superexchange interaction due to the virtual hopping of electrons from O-2p filled states to Mn-/Ni-3d empty states is enhanced when the band gap formed by crystal-field splitting decreases, thus the effective exchange parameters and Curie temperature increase as Mn4+—O2-—Ni2+ length increases. The ferroelectric distortion in Bi2NiMnO6 is directly from the hybridization of Bi-6p and O-2p states. The role of Bi-6s2 lone pairs electrons may be that hybridized O-2p with Bi-6s orbitals may be more appropriate in compatible symmetry with Bi-6p orbital than O-2p orbital only. Furthermore, the route of ferroelectric distortion in Bi2NiMnO6 from paraelectric P21/n phase to ferroelectric C2 phase is discussed.
Urban Growth and Long-Term Changes in Natural Hazard Risk
Authors: Chang Stephanie E , Gregorian Martin , Pathman Karthick , Yumagulova Lilia , Tse Wendy
Published: April 2012

This paper explores the question of whether natural hazard risks for urban areas are growing or diminishing over time. While trends such as population growth in hazardous areas increase the potential for loss in disaster events, other factors, such as improved building codes, tend to reduce this risk. The net effects of such urban changes are examined through the use of simulation models that estimate disaster losses. In a comparative static approach, losses are modeled for the same hypothetical hazard event striking at different points in an urban area's development history. The analysis focuses on a case study of seismic hazard for the metropolitan area of Vancouver, Canada. Results of a casualty-estimation model applied retrospectively indicate that, for the same M7.3 seismic event, human casualties would have been similar if the earthquake had struck in 2006 as in 1971, even though the population at risk had doubled in the interim. This improvement in per capita casualty rate is largely due to building-code upgrades and changes in new construction. Other dimensions of risk worsened, however: the estimated population in significantly damaged buildings increased by some 60% for the region and, in some fast-growing municipalities, more than doubled. Using a similar analytical approach, a second modeling effort focused on transportation systems and considered the risk implications of future growth. Analysis compared transportation disruption in 2004 and 2021 for a constant earthquake hazard but a forecast 21% increase in traffic. Results indicate that, for the Vancouver metropolitan area overall, disaster risk to transportation is expected to decrease slightly due to the shifting geography of residences and workplaces. The spatial distribution of risk would change, however: in particular, it would worsen for the older urban core. Moreover, the relative importance of key bridges changed over time. The analyses here indicate that in this case study, risk is not worsening significantly overall but is undergoing notable spatial redistribution; however, the extent to which this finding can be generalized to other urban areas and types of hazards remains to be investigated.
Network Nation
Authors: Jones Rhys , Merriman Peter
Published: April 2012

Academics have increasingly begun to question the significance of bounded understandings of space and place, preferring instead to approach places as open, dynamic, relational entities that are in-formation, and the ways in which different places are connected by flows of people, ideas, and material things. The aim of this paper is to focus on the implications of networked and relational ways of thinking for how we understand the notion of ‘territory’, the archetypal example of bounded space. We discuss the need to develop a greater dialogue between relational and territorial understandings of space by exploring recent work on national territories. We contend that (1) the discourses and embodied practices of actors and (2) a whole series of objects are actively involved in producing a national territory that is open, contingent, and contested. The paper focuses on empirical material relating to Welsh roads and road signs—in particular the campaign in favour of bilingual road signs in Wales during the late 1960s and 1970s—as a way of highlighting the significance of these two themes. We conclude by arguing that territories are not relics of a static world of nation-states but, rather, the contingent products of an ongoing series of connections between people, discourses, and objects.
The problem of affectivity in cognitive theories of emotion
Authors: Salmela Mikko
Published: April 2012

Despite their paradigmatic status in the modern philosophy of emotions, cognitive theories have been criticized for failing to provide a satisfactory account of affectivity in emotions. I agree with much of this criticism, but I argue that an amended cognitive theory can overcome the flaws of the two main theories, strong cognitivism and componential cognitivism. I argue that feeling cannot be reduced to the evaluative content of emotion and attitudinal mode of holding it as strong cognitivists suggest. Typical emotional feelings are induced by either propositionally explicable or biologically “hard-wired” evaluations instead of being involved in the latter. We, then, face the challenge of explaining why the feeling and the evaluative construal that figure into an emotion are aspects of the same state, unlike occasional feelings and thoughts that happen to occur in us at the same time. I propose that evaluative content and feeling are different kinds of representations of the formal property of an emotional object. This is a second-order property that is ascribed to every individual object of a particular emotion-type in virtue of its perceived first-order properties and that is experienced as a property of those objects in a state of emotion. Evaluative content involves a conceptual representation of the formal property while feeling represents its inherent affective quality.
Romaphobia among Serbian and Dutch adolescents: The role of perceived threat, nationalistic feelings, and integrative orientations
Authors: Ljujic Vanja , Vedder Paul , Dekker Henk , Geel Mitch
Published: April 2012

This study examines the relationships between nationalism and integration attitudes on one hand, and anti‐Roma prejudice on the other. Using Stephan and Stephan's threat theory, the study analyzes whether and to what extent these relationships are mediated by perceived economic and symbolic threats. Data were collected among 16‐ and 17‐year‐old students in Serbia and The Netherlands. A path analysis shows that perceived economic and symbolic threats mediate the relationships between nationalism and integration on one hand, and Romaphobia on the other. Moreover, the findings show that these relationships are comparable between Serbian and Dutch youth. Levels of threat and Romaphobia differ between countries. Youth in the Netherlands, who barely have contact opportunities with Roma, are characterized by higher threat and Romaphobia scores than Serbian youth, who have proportionally more contact opportunities. Explanations are discussed as well as implications for theory and prejudice reduction in diverse intercultural settings.
Comparing different boosters of planning interventions on changes in fat consumption in overweight and obese individuals: A randomized controlled trial
Authors: Scholz Urte , Ochsner Sibylle , Luszczynska Aleksandra
Published: April 2012

Single planning interventions have been found to promote short‐term dietary change. Repeated planning interventions may foster long‐term effects on behavior change. It remains unknown whether there is a critical number of boosters to establish long‐term maintenance of behavioral changes. This study aimed at investigating what social‐cognitive variables mediate the effects of the interventions on dietary behavior change. Overall, 373 participants (n = 270 women, 72.4%; age M = 52.42, SD = 12.79) were randomly allocated to one of five groups: a control group, a single planning group, and three groups with 3, 6, or 9 weeks’ repeated planning interventions. Follow‐ups took place 4, 6, and 12 months after baseline. Change in fat consumption was not promoted by any of the interventions. In terms of social‐cognitive variables, intentions, self‐efficacy and coping planning displayed a time × group interaction, with the 9 weeks’ planning group showing the most beneficial effects. Effect sizes, however, were very small. None of the tested planning interventions successfully promoted change in fat consumption across the 12 month period. This, however, could not be explained by problems with adherence to the intervention protocol. Potential explanations for this unexpected result are discussed.
Psychosocial wellbeing in the Central and Eastern European transition: An overview and systematic bibliographic review
Authors: Eiroá Orosa Francisco José
Published: April 2012

This paper presents the results of a systematic review of literature on the psychosocial wellbeing of populations in Central and Eastern Europe during the transition period subsequent to the fall of the Soviet Bloc. A revision of research addressing emotional wellbeing trends in this period and theoretical models was carried in order to verify their validity in the analysis of empirical studies. Hence, a systematic bibliographic review was conducted, aiming to find possible subjective mediators between social variables derived from changes and emotional wellbeing. The results of the review show that subjective mediators such as locus of control, perceived control, self‐efficacy beliefs, perceived familial support, and the subjective evaluation of social change explain part of the relationship between macrosocial changes and emotional wellbeing. Results appear coherent with proposed multidimensional models of social change and mental health, although further research should be conducted to determine the specific weight of these phenomena in individual emotional wellbeing.
Self‐focused cognitive emotion regulation style as associated with widespread diminished EEG fractal dimension
Authors: Bornas Xavier , Tortella‐Feliu Miquel , Balle Maria , Llabrés Jordi
Published: April 2012

The cognitive regulation of emotions is important for human adaptation. Self‐focused emotion regulation (ER) strategies have been linked to the development and persistence of anxiety and depression. A vast array of research has provided valuable knowledge about the neural correlates of the use of specific self‐focused ER strategies; however, the resting neural correlates of cognitive ER styles, which reflect an individual's disposition to engage in different forms of ER in order to manage distress, are largely unknown. In this study, associations between theoretically negative ER style (self‐focused or not) and the complexity (fractal dimension, FD) of the resting EEG at frontal, central, parietal, and occipital regions were investigated in 58 healthy volunteers. The Cognitive Emotion Regulation Questionnaire was used as the self‐report measure of ER style. Results showed that a diminished FD over the scalp significantly correlated with self‐focused ER style scores, even after controlling for negative affect, which has been also considered to influence the use of ER strategies. The lower the EEG FD, the higher were the self‐focused ER style scores. Correlational analyses of specific self‐focused ER strategies showed that self‐blaming and rumination were negatively associated with diminished FD of the EEG, but catastrophizing and blaming others were not. No significant correlations were found for ER strategies more focused on situation or others. Results are discussed within the self‐organized criticality theory of brain dynamics: The diminished FD of the EEG may reflect a disposition to engage in self‐focused ER strategies as people prone to ruminate and self‐blame show a less complex resting EEG activity, which may make it more difficult for them to exit their negative emotional state.
Effects of Turtle Excluder Devices (TEDs) on the Bycatch of Three Small Coastal Sharks in the Gulf of Mexico Penaeid Shrimp Fishery
Authors: Raborn Scott W. , Gallaway Benny J. , Cole John G. , Gazey William J. , Andrews Kate I.
Published: April 2012

The stock of blacknose sharks Carcharhinus acronotus in the U.S. South Atlantic and the Gulf of Mexico is overfished, and according to the 2007 stock assessment conducted by the National Marine Fisheries Service overfishing continues to occur. Penaeid shrimp trawl bycatch rates in the Gulf of Mexico were modeled for this species as well as for the Atlantic sharpnose shark Rhizoprionodon terraenovae and bonnethead shark Sphyrna tiburo using a combination of research trawl and observer data. Research trawls have never used turtle excluder devices (TEDs), which are expected to exclude larger specimens of blacknose sharks. Most of the observer data that contain blacknose shark occurrences were collected during the pre-TED era when the two data sets tracked one another. Minimum observer data were available for the post-TED period (1990–present). As a consequence, the pre-TED (1972–1989) relationship between observer and research trawl catch per unit effort (CPUE) is driving the observer CPUE estimates from 1990 to the present, a period characterized by increased blacknose shark abundance. We suspected that the increase in predicted observer CPUE in the post-TED era is an artifact of application of the pre-TED observer and research trawl relationship to the post-TED era. This suspicion led us to question whether the bycatch of these species was altered due to the use of TEDs. We used negative binomial regression in a before-after-control-impact setting to test the effects of TEDs on the bycatch rates of these small coastal sharks. The TED effect was found to substantially reduce the bycatch of blacknose sharks (by 94%) and to do so moderately for bonnethead sharks (31%); the results were inconclusive for Atlantic sharpnose sharks. The management implication of our findings is that the existing small coastal shark–penaeid shrimp fishery bycatch model needs to be modified or replaced with a model that explicitly incorporates the potential for a TED effect.

Received March 23, 2011; accepted December 15, 2011
Providing Aid Agencies with Tools for Conflict-Sensitive Practice: Lessons Learned from Peace and Conflict Impact Assessment (PCIA)
Authors: Leonhardt Manuela
Published: April 2012

Peace and Conflict Impact Assessment (PCIA) and other conflict-sensitive analytical tools are currently high on the agenda of development and humanitarian organisations. This article asks how far these tools can actually contribute to better development and humanitarian assistance in the context of conflict. For this, it attempts to match agency expectations with the existing tools for conflict analysis and impact assessment. It discusses key methodological challenges to developing conflict-sensitive tools and looks at the lessons learned from using them within aid administrations. The paper concludes on a cautious note, calling for more realistic expectations regarding the analysis that can be provided and reminding aid agencies that tools are just one element in the complex process of mainstreaming conflict-sensitivity.
Making the Case for a Regional Approach to to Peacebuilding
Authors: Tschirgi Necla
Published: April 2012

Since the early 1990s, peacebuilding has emerged as a new agenda at the United Nations and among key international actors. Lying at the intersection of development and security, peacebuilding encompasses socio-economic, political, diplomatic, military and security dimensions. Currently, peacebuilding policies and programming deal primarily with issue or country specific challenges, as most violent conflicts now occur within, not among, states. Arguing that contemporary conflicts are actually transnational in nature, this article proposes a complementary level of analysis and action for more effective peacebuilding: viewing peacebuilding from a regional conflict framework and identifying regionally-grounded approaches to address the twin challenges of security and development. Specifically, the article draws attention to regional variations in conflict formations and dynamics, and to their peacebuilding implications. It concludes that a regional approach to peacebuilding requires new analytical tools, creative mechanisms of collaboration among local, regional and international actors, strengthening of regional and sub-regional organisations, and ultimately, significant reform of the current architecture of international development and security.