bluuebunny/crossref_metadata_2025_split huggingface dataset:
Strain control in germanium nanowires: the use of a silicon nitride shell
Authors: Dupré Ludovic , Buttard Denis , Gentile Pascal , Benoit à la Guillaume Quentin , Gorisse Thérèse , Renevier Hubert 
Published: March 2014

AbstractThe core–shell geometry is a strong tool for inducing and controlling strains in nano‐objects in order to tune their optoelectronic properties. We synthesized and characterized core–shell nanostructures by depositing a non‐epitaxial silicon nitride shell around germanium nanowires. Scanning electron microscopy as well as energy dispersive X‐ray spectroscopy confirms the structural integrity of the heterostructures, and grazing incidence X‐ray diffraction measurements reveal the presence of a radial tensile strain in the Ge nanowires. A control of this strain is then demonstrated up to 0.3% by adjusting the SiNx shell thickness versus Ge nanowire diameter. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Aerobic Biodegradation of Hydrocarbons in High Temperature and Saline Groundwater
Authors: Kashir Mansor , Barker Jim , McGregor Rick , Shouakar‐Stash Orfan 
Published: March 2014

A series of laboratory microcosm experiments and a field pilot test were performed to evaluate the potential for aerobic biodegradation of aromatic hydrocarbons and methyl tert‐butyl ether (MtBE; a common oxygenate additive in gasoline) in saline, high temperature (>30° C) groundwater. Aquifer, sediment, and groundwater samples from two sites, one in Canada and another in Saudi Arabia, were incubated for 106 days to evaluate the changes in select hydrocarbon and MtBE concentrations and microbial community structure. Almost complete biodegradation of the aromatic hydrocarbons was found in the Saudi Arabian microcosm samples whereas the Canadian microcosm samples showed no significant biodegradation during the laboratory testing. MtBE degradation was not observed in either set of microcosms. Denaturing gradient gel electrophoresis analyses showed that, while the Canadian microorganisms were the most diverse, they showed little response during incubation. The microbial communities for the Saudi Arabian sample contained significant numbers of microorganisms capable of hydrocarbon degradation which increased during incubation.Based on the laboratory results, pilot‐scale testing at the Saudi Arabian field site was carried out to evaluate the effectiveness of enhanced aerobic biodegradation on a high temperature, saline petroleum hydrocarbon plume. Dissolved oxygen was delivered to the subsurface using a series of oxygen diffusion emitters installed perpendicular to groundwater flow, which created a reactive zone. Results obtained from the seven‐month field trial indicated that all the target compounds decreased with removal percentages varying between 33 percent for the trimethylbenzenes to greater than 80 percent for the BTEX compounds. MtBE decreased 40 percent on average whereas naphthalene was reduced 85 percent on average. Examination of the microbial population upgradient and downgradient of the emitter reactive zone suggested that the bacteria population went from an anaerobic, sulfate‐reducing dominated population to one dominated by a heterotrophic aerobic bacteria dominant population.These studies illustrate that field aerobic biodegradation may exceed expectations derived from simple laboratory microcosm experiments. Also, high salinity and elevated groundwater temperature do not appear to inhibit in situ aerobic biorestoration. © 2014 Wiley Periodicals, Inc.
Security analysis of SM2 key exchange protocol in TPM2.0
Authors: Zhao Shijun , Xi Li , Zhang Qianying , Qin Yu , Feng Dengguo 
Published: March 2014

AbstractThe new released trusted platform module (TPM) specification, TPM2.0, adds cryptographic support for key exchange by providing SM2 authenticated key exchange (AKE) application programming interface (API) commands. Xu analyzed the SM2 AKE protocol and found that it was insecure in common computing environment by presenting two types of unknown key share attacks. Here, we present another design weakness of the SM2 AKE protocol, which might cause that the protocol cannot be proven secure in modern security models. We also analyze the security of SM2 AKE protocol in TPM2.0, whose running environment is very different and find that (i) it indeed gets some security improvements through the protection capability provided by the two SM2 AKE commands of TPM2.0 but (ii) it still has some weaknesses, which might lead to unknown key share and key‐compromise impersonation attacks because of the bad design of the TPM2.0 application programming interface. We solve the weaknesses of SM2 AKE protocol in TPM2.0 by slightly modifying one SM2 AKE command and finally give a formal proof of our solution in the Canetti and Krawczyk model. Our work shows that TPM2.0 could provide a proven secure SM2 AKE by slightly modifying one command. Copyright © 2014 John Wiley & Sons, Ltd.
Exact approaches for testing hypotheses based on the intra‐class kappa coefficient
Authors: Wilding Gregory E. , Consiglio Joseph D. , Shan Guogen 
Published: March 2014

AbstractTesting involving the intra‐class kappa coefficient is commonly performed in order to assess agreement involving categorical ratings. A number of procedures have been proposed, which make use of the limiting null distribution as the sample size goes to infinity in order to compute the observed significance. As with many tests based on asymptotic null distributions, these tests are associated with problematic type I error control for selected sample sizes and points in the parameter space. We propose and study a collection of exact testing approaches for both the one‐sample and K‐sample scenarios. For the one‐sample case, p‐values are obtained using the exact distribution of the test statistic conditional on a sufficient statistic. In addition, unconditional approaches are considered on the basis of maximization across the nuisance parameter space. Numerical evaluation reveals advantages with the exact unconditional procedures. Copyright © 2014 John Wiley & Sons, Ltd.
Analysis of transmit antenna selection/orthogonal space‐time block coding with receive selection and combining in the presence of feedback errors
Authors: Coşkun Ahmet F. , Kucur Oğuz 
Published: March 2014

AbstractExamining the effect of imperfect transmit antenna selection (TAS) caused by the feedback link errors on the performance of hybrid TAS/orthogonal space‐time block coding (OSTBC) with single receive antenna selection (i.e., joint transmit and receive antenna selection (JTRAS)/OSTBC) and TAS/OSTBC (with receive maximal‐ratio combining‐like combining structure) over slow and frequency‐flat Nakagami‐m fading channels is the main objective of this paper. Under ideal channel estimation and delay‐free feedback assumptions, statistical expressions and several performance metrics related to the post‐processing signal‐to‐noise ratio are derived by defining a unified system model concerning both JTRAS/OSTBC and TAS/OSTBC schemes. Exact analytical expressions for outage probability (OP) and bit/symbol error rates of M‐ary modulations are presented in order to provide a detailed examination on the OP and error performances of the unified system that experiences feedback errors. Also, the asymptotic diversity order analysis, which shows that the diversity order of the investigated schemes is equal to the diversity order provided by OSTBC transmission itself, is included in the paper. Moreover, we have validated the theoretical results via Monte Carlo simulations. Copyright © 2014 John Wiley & Sons, Ltd.
Construction of Two New Mixed‐ligand Coordination Polymers based on 2,2′‐Dimethylbiphenyl‐4,4′‐dicarboxylic Acid
Authors: Xie Yan , Wang Tingting , Zeng Heping 
Published: March 2014

AbstractTwo mixed‐ligand coordination polymers (CPs) based on a biphenyl‐based dicarboxylate ligand and 4,4′‐bipyridine or imidazole co‐ligand, namely, [Co(DMBDA)(bpy)]n (1) (H2DMBDA = 2,2′‐dimethylbiphenyl‐4,4′‐dicarboxylic acid, bpy = 4,4′‐bipyridine) and [Zn(DMBDA)(Im)]n (2) (Im = imidazole), were obtained under hydrothermal conditions. Compound 1 exhibits a new (4,6)‐connected network with a {44·610·8}{44·62} Schläfli symbol, whereas compound 2 shows a 4‐connected NbO‐type topology. These coordination polymers represent two rare examples of CPs based on 2,2′‐dimethylbiphenyl‐4,4′‐dicarboxylic acid. The solid‐state luminescent behaviors of the novel CPs were also investigated at room temperature.
Apathy in Nursing Home Residents with Dementia: Results From A Cluster-Randomized Controlled Trial
Authors: Treusch Y. , Majic T. , Page J. , Gutzmann H. , Heinz A. , Rapp M.A. 
Published: March 2014

AbstractPurpose:Here we evaluate an interdisciplinary occupational and sport therapy intervention for dementia patients suffering from apathy.Subjects and methods:A prospective, controlled, rater-blinded, clinical trial with two follow-ups was conducted as part of a larger cluster-randomized trial in 18 nursing homes in Berlin. n = 117 dementia patients with apathy, defined as a score of 40 or more on the apathy evaluation scale (AES) or presence of apathy on the Neuropsychiatric Inventory (NPI), were randomly assigned to intervention or control group. The intervention included 10 months of brief activities, provided once a week. The primary outcome measure was the total score on the AES scale measured directly after the intervention period and again after 12 months.Results:We found significant group differences with respect to apathy during the 10 month intervention period (F2,82 = 7.79, P < 0.01), which reflected an increase in apathy in the control group, but not in the intervention group. Within one year after the intervention was ceased, the treatment group worsened and no longer differed significantly from the control group (P = 0.55).Conclusions:Our intervention was effective for the therapy of apathy in dementia, when applied, but not one year after cessation of therapy.
The need for public policies to promote healthier food consumption: A comment on Wansink and Chandon (2014)
Authors: Roberto Christina A. , Pomeranz Jennifer L. , Fisher Jennifer O. 
Published: March 2014

AbstractCurrent approaches to addressing obesity have fallen short. This is largely due to the many environmental forces that undermine people's self‐regulatory capacity to be personally responsible for their food choices. Novel insights from the social sciences are needed to inform voluntary, health‐promoting actions by companies, institutions, and citizens as well as the design of public health policies. Voluntary interventions that rely on nudges should complement traditional public health strategies such as taxation and restriction of child‐targeted marketing in schools. In this commentary, we discuss four food policy issues that would benefit from consumer psychology research: (a) the restriction of food marketing to children, (b) provision of nutrition information through food labels, (c) improving school food environments, and (d) placing limits on portion sizes. Identifying effective solutions for obesity will require approaches that integrate psychological, public health, and legal perspectives and methods.
Acute Mountain Sickness Is Not Repeatable Across Two 12-Hour Normobaric Hypoxia Exposures
Authors: MacInnis Martin J. , Koch Sarah , MacLeod Kristin E. , Carter Eric A. , Jain Radha , Koehle Michael S. , Rupert Jim L. 
Published: March 2014

Objective The purposes of this experiment were to determine the repeatability of acute mountain sickness (AMS), AMS symptoms, and physiological responses across 2 identical hypoxic exposures. Methods Subjects (n = 25) spent 3 nights at simulated altitude in a normobaric hypoxia chamber: twice at a partial pressure of inspired oxygen (PIO2) of 90 mmHg (4000 m equivalent; “hypoxia”) and once at a PIO2 of 132 mmHg (1000 m equivalent; “sham”) with 14 or more days between exposures. The following variables were measured at hours 0 and 12 of each exposure: AMS severity (ie, Lake Louise score [LLS]), AMS incidence (LLS ≥3), heart rate, oxygen saturation, blood pressure, and the fraction of exhaled nitric oxide. Oxygen saturation and heart rate were also measured while subjects slept. Results The incidence of AMS was not statistically different between the 2 exposures (84% vs 56%, P > .05), but the severity of AMS (ie, LLS) was significantly lower on the second hypoxic exposure (mean [SD], 3.1 [1.8]) relative to the first hypoxic exposure (4.8 [2.3]; P < .001). Headache was the only AMS symptom to have a significantly greater severity on both hypoxic exposures (relative to the sham exposure, P < .05). Physiological variables were moderately to strongly repeatable (intraclass correlation range 0.39 to 0.86) but were not associated with AMS susceptibility ( P > .05). Conclusions The LLS was not repeatable across 2 identical hypoxic exposures. Increased familiarity with the environment (not acclimation) could explain the reduced AMS severity on the second hypoxic exposure. Headache was the most reliable AMS symptom.
On the motive of the group of units of a division algebra
Authors: Shinder Evgeny 
Published: March 2014

AbstractWe consider the algebraic group GL1 (A), where A is a division algebra of prime degree over a field F, and the associated motive in the Voevodsky category of motivic complexes (F). We relate the motive of GL1 (A) to the motive of the Čech simplicial scheme χ, associated to the Severi-Brauer variety of A, and compute the second differential in the resulting spectral sequence for motivic cohomology.
Bubbling reduces intermittency in turbulent thermal convection
Authors: Lakkaraju Rajaram , Toschi Federico , Lohse Detlef 
Published: March 2014

AbstractIntermittency effects are numerically studied in turbulent bubbling Rayleigh–Bénard (RB) flow and compared to the standard RB case. The vapour bubbles are modelled with a Euler–Lagrangian scheme and are two-way coupled to the flow and temperature fields, both mechanically and thermally. To quantify the degree of intermittency we use probability density functions, structure functions, extended self-similarity (ESS) and generalized extended self-similarity (GESS) for both temperature and velocity differences. For the standard RB case we reproduce scaling very close to the Obukhov–Corrsin values common for a passive scalar and the corresponding relatively strong intermittency for the temperature fluctuations, which are known to originate from sharp temperature fronts. These sharp fronts are smoothed by the vapour bubbles owing to their heat capacity, leading to much less intermittency in the temperature but also in the velocity field in bubbling thermal convection.
Stochastic modelling of transverse wave instability in a liquid-propellant rocket engine
Authors: Popov Pavel P. , Sideris Athanasios , Sirignano William A. 
Published: March 2014

AbstractThe combustion stability of a liquid-propellant rocket engine experiencing a random, finite perturbation from steady-state conditions is examined. The probability is estimated for a nonlinear resonant limit-cycle oscillation to be triggered by a random disturbance. Transverse pressure waves are considered by using a previously published two-dimensional nonlinear pressure wave equation coupled with Euler equations governing the velocity components. The cylindrical combustion chamber is a complex system containing multiple co-axial methane–oxygen injectors; each co-axial jet is analysed for mixing and burning on its own local grid scheme, with the energy release rate coupled to the wave oscillation on the more global grid. Two types of stochastic forcing for the random disturbance are explored: a travelling Gaussian pressure pulse and an oscillating pressure dipole source. The random variables describing the pulse are magnitude, location, duration and orientation of the disturbances. The polynomial chaos expansion (PCE) method is used to determine the long-time behaviour and infer the asymptote of the solution to the governing partial differential equations. Depending on the random disturbance, the asymptote could be the steady-state solution or a limit-cycle oscillation, e.g. a first tangential travelling wave mode. The asymptotic outcome is cast as a stochastic variable which is determined as a function of input random variables. The accuracy of the PCE application is compared with a Monte Carlo calculation and is shown to be significantly less costly for similar accuracy.
Vibrational Behavior of an Electrically Actuated Micro-Beam with Thermoelastic Damping
Authors: Karami mohammadi A. , Ale Ali N. 
Published: March 2014

ABSTRACTIn this paper, a resonator is modeled as a microbeam under the effect of thermoelastic damping and actuated electrically. Two models, small and large deformation models, are represented by considering linear and nonlinear Euler-Bernoulli beam theory. These models are compared against voltage, and the difference between these models is shown and discussed. In the large deformation model, the microbeam deflected due to applied DC voltage, and vibration of microbeam occurs around this static deflection. The vibration equation is linearized around static deflection and by applying harmonic vibration, equation for mode shape and frequency is obtained. The complex frequency is calculated by numerical method and then used for obtaining the Q-factor of thermoelastic damping. The stretching effect and thermoelastic damping is validated with the literature. The result shows that for the high values of voltage, the large deformation model is more accurate. The behavior of thermoelastic damping is also investigated against the geometrical and material properties.
Dietary cholesterol supplementation to a plant-based diet suppresses the complete pathway of cholesterol synthesis and induces bile acid production in Atlantic salmon (Salmo salarL.)
Authors: Kortner Trond M. , Björkhem Ingemar , Krasnov Aleksei , Timmerhaus Gerrit , Krogdahl Åshild 
Published: March 2014

Plants now supply more than 50 % of protein in Norwegian salmon aquafeeds. The inclusion of plant protein in aquafeeds may be associated with decreased lipid digestibility and cholesterol and bile salt levels, indicating that the replacement of fishmeal with plant protein could result in inadequate supplies of cholesterol in fish. A reduction in feed efficiency, fish growth and pathogen resistance is often observed in parallel to alterations in sterol metabolism. Previous studies have indicated that the negative effects induced by plant components can be attenuated when diets are supplemented with cholesterol. The present study evaluated the effects of dietary cholesterol supplementation (1·5 %) in Atlantic salmon fed a plant-based diet for 77 d. The weights of body, intestines and liver were recorded and blood, tissues, faeces, chyme and bile were sampled for the evaluation of effects on growth, nutrient utilisation and metabolism, and transcriptome and metabolite levels, with particular emphasis on sterol metabolism and organ structure and function. Cholesterol supplementation did not affect the growth or organ weights of Atlantic salmon, but seemed to promote the induction of cholesterol and plant sterol efflux in the intestine while suppressing sterol uptake. Cholesterol biosynthesis decreased correspondingly and conversion into bile acids increased. The marked effect of cholesterol supplementation on bile acid synthesis suggests that dietary cholesterol can be used to increase bile acid synthesis in fish. The present study clearly demonstrated how Atlantic salmon adjusted their metabolic functions in response to the dietary load of cholesterol. It has also expanded our understanding of sterol metabolism and turnover, adding to the existing, rather sparse, knowledge of these processes in fish.
Renal function associates with energy intake in elderly community-dwelling men
Authors: Luis Desiree , Huang Xiaoyan , Sjögren Per , Risérus Ulf , Ärnlöv Johan , Lindholm Bengt , Cederholm Tommy , Carrero Juan Jesus 
Published: March 2014

Energy intake and renal function decrease with age. In patients with chronic kidney disease (CKD), spontaneous food intake decreases in parallel with the loss of renal function. The objective of the present study was to evaluate a possible relationship between renal dysfunction and energy intake in elderly community-dwelling men. A cross-sectional study including 1087 men aged 70 years from the Uppsala Longitudinal Study of Adult Men (ULSAM) community-based cohort was carried out. Dietary intake was assessed using 7 d food records, and glomerular filtration rate was estimated from serum cystatin C concentrations. Energy intake was normalised by ideal body weight, and macronutrient intake was energy-adjusted. The median normalised daily energy intake was 105 (interquartile range 88–124) kJ, and directly correlated with estimated glomerular filtration rate (eGFR) as determined by univariate analysis. Across the decreasing quartiles of eGFR, a significant trend of decreasing normalised energy intake was observed (P =0·01). A multivariable regression model including lifestyle factors and co-morbidities was used for predicting total energy intake. In this model, regular physical activity (standardised β = 0·160;P =0·008), smoking (standardised β = − 0·081;P =0·008), hypertension (standardised β = − 0·097;P =0·002), hyperlipidaemia (standardised β = − 0·064;P =0·037) and eGFR (persdincrease, standardised β = 0·064;P =0·04) were found to be independent predictors of energy intake. Individuals with manifest CKD (eGFR < 60 ml/min per 1·73 m2) were more likely to have lower energy intake than those without. In conclusion, there was a direct and independent correlation between renal function and energy intake in a population-based cohort of elderly men. We speculate on a possible link between renal dysfunction and malnutrition in the elderly.
In vitro leishmanicidal activity of pyrazole-containing polyamine macrocycles which inhibit the Fe-SOD enzyme of Leishmania infantum and Leishmania braziliensis species
Authors: NAVARRO P. , SÁNCHEZ-MORENO M. , MARÍN C. , GARCÍA-ESPAÑA E. , RAMÍREZ-MACÍAS I. , OLMO F. , ROSALES M. J. , GÓMEZ-CONTRERAS F. , YUNTA M. J. R. , GUTIERREZ-SÁNCHEZ R. 
Published: March 2014

SUMMARYThe in vitro leishmanicidal activity and cytotoxicity of pyrazole-containing macrocyclic polyamines 1–4 was assayed on Leishmania infantum and Leishmania braziliensis species. Compounds 1–4 were more active and less toxic than glucantime and both infection rates and ultrastructural alterations confirmed that 1 and 2 were highly leishmanicidal and induced extensive parasite cell damage. Modifications in the excretion products of parasites treated with 1–3 were also consistent with substantial cytoplasm alterations. Compound 2 was highlighted as a potent inhibitor of Fe-SOD in both species, whereas its effect on human CuZn-SOD was poor. Molecular modelling suggested that 2 could deactivate Fe-SOD due to a sterically favoured enhanced ability to interact with the H-bonding net that supports the enzyme`s antioxidant features.