bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐performance doubly fed induction machine drive system using predictive direct torque control drive system fed by indirect matrix converters
Authors: Behnia Hamid , Faraji Vahid , Aghasi Majid , Arab Khaburi Davood 
Published: February 2013

SUMMARYThis paper presents a novel predictive direct torque control for doubly fed induction machine based on indirect matrix converter (IMC), which is characterized by its simple structure, minimal‐torque ripple, and constant switching frequency. Nowadays, the control strategies based on predictive methods have proved their efficiency to improve drive systems capabilities. So, in this paper, one of the best predictive methods that have recently been suggested for doubly fed induction machine drive systems is applied to IMC. The purpose of this combination is to modify the control parameters and size/volume reduction of drive system structure, which is difficult to achieve in conventional systems based on voltage source inverters. The good tracking behavior with reduced torque and flux ripple for both motoring and generating modes as well as removing bulky electrolytic capacitor from the DC link of a converter resulted by using three vectors, two active vectors together with one zero vector per switching period, and applying these vectors to the inverter stage of IMC. To improve the motor drive system performance and reduce losses caused by snubber circuits, the rectifier four‐step commutation method in rectifier bridge is used. In the inverter stage, the predictive direct torque control method is employed. The simulation results of the proposed model confirm its effectiveness and accuracy. Copyright © 2013 John Wiley & Sons, Ltd.
Generalized optical gain analysis in nonparabolic semiconductor laser
Authors: Dey Anup , Maiti Biswajit , (Sarkar) Debasree Chanda 
Published: February 2013

SUMMARYA simple generalized theory is developed for optical gain of nonparabolic semiconductor lasers based on the three‐band model of Kane, by taking into account the wave‐vector () dependence of the optical matrix element. The gain in laser of nonparabolic semiconductors is demonstrated, by taking InAs, InSb, Hg1−xCdxTe and In1−xGaxAsyP1−y lattice matched to InP as examples, and it has been found that the peak of the gain spectra for a given carrier density is higher in the three‐band model of Kane than those with parabolic energy band approximations in all the cases. The difference between the peak of gain spectra for three‐band model and the parabolic band model is greater for laser of narrow band gap materials in comparisons with that of laser of wide band gap materials, thereby reveals the necessity for inclusion of the nonparabolicity in modeling lasers of small band gap materials. The well‐known results for wide band gap materials having parabolic energy bands has also been obtained from our generalized formulation under certain limiting condition. Copyright © 2013 John Wiley & Sons, Ltd.
Topological mapping methods for α‐helical bacterial membrane proteins – an update and a guide
Authors: Islam Salim T. , Lam Joseph S. 
Published: February 2013

AbstractIntegral membrane proteins with α‐helical transmembrane segments (TMS) are known to play important and diverse roles in prokaryotic cell physiology. The net hydrophobicity of TMS directly corresponds to the observed difficulties in expressing and purifying these proteins, let alone producing sufficient yields for structural studies using two‐/three‐dimensional (2D/3D) crystallographic or nuclear magnetic resonance methods. To gain insight into the function of these integral membrane proteins, topological mapping has become an important tool to identify exposed and membrane‐embedded protein domains. This approach has led to the discovery of protein tracts of functional importance and to the proposition of novel mechanistic hypotheses. In this review, we synthesize the various methods available for topological mapping of α‐helical integral membrane proteins to provide investigators with a comprehensive reference for choosing techniques suited to their particular topological queries and available resources.
Short‐term, high fat feeding‐induced changes in white adipose tissue gene expression are highly predictive for long‐term changes
Authors: Voigt Anja , Agnew Katrin , van Schothorst Evert M. , Keijer Jaap , Klaus Susanne 
Published: February 2013

ScopeWe aimed to evaluate the predictability of short‐term (5 days) changes in epididymal white adipose tissue (eWAT) gene expression for long‐term (12 weeks) changes induced by high‐fat diet (HFD) feeding.Methods and resultsMice were fed semisynthetic diets containing 10 (low‐fat diet) or 40 (HFD) energy% of fat. Global gene expression in eWAT was analyzed using microarrays and confirmed by quantitative PCR. As expected, HFD feeding resulted in increased body fat accumulation and reduced glucose tolerance after 12 weeks. A total of 4678 transcripts were significantly changed by HFD after 12 weeks and 973 after 5 days, with an overlap of 764 transcripts encoding 549 genes. Of these, 79% were downregulated and 21% were upregulated by HFD, all in the same direction and highly correlated (r2 = 0.90) between the time points. Pathway analysis showed downregulation of the main identified processes: lipid metabolism, carbohydrate metabolism, and oxidative phosphorylation. Mest (mesoderm‐specific transcript) was highly upregulated, confirming its role as an early marker of fat cell expansion.ConclusionThe high predictive value of short‐term gene expression changes for long‐term effects of high fat feeding is a promising step to establish robust early biomarkers that could shorten animal trials to assess health‐promoting food compounds.
Identification and mitigation of interference sources present in SSB‐based wireless MRI receiver arrays
Authors: Riffe Matthew J. , Twieg Michael D. , Gudino Natalia , Blumenthal Colin J. , Heilman Jeremiah A. , Griswold Mark A. 
Published: February 2013

PurposeSingle sideband amplitude modulation (SSB) is an appealing platform for highly parallel wireless MRI detector arrays because the spacing between channels is ideally limited only by the MRI signal bandwidth. However this assumes that no other sources of interference are present outside that bandwidth. This work investigates the practical interference between multiple SSB‐encoded MRI signals.MethodsNoise from coil preamplifiers and carrier bleed‐through are identified as sources of interference. Two different SSB systems were designed for 1.5 T with different noise filtering properties. We show how the differences between the filtered noise profiles impact the received MR signal's dynamic range (DRsig) and image signal‐to‐noise ratio through simulation, bench measurements, and phantom imaging experiments.ResultsWhen operating individually in the MR scanner, both SSB systems were shown to minimally impact the original DRsig and signal‐to‐noise ratio. Conversely, when all eight channels were operating simultaneously, an average signal‐to‐noise ratio loss was observed to be 12% in the one system, while a second system with more complex filtering was able to achieve a 3% loss in signal‐to‐noise ratio.ConclusionSuccessful wireless transmission of multiple SSB‐encoded MRI signals is possible as long as channel interference is properly managed through design and simulation. Magn Reson Med 70:1775–1786, 2013. © 2013 Wiley Periodicals, Inc.
Inverse‐motion‐based form finding for quasi‐incompressible finite electroelasticity
Authors: Ask Anna , Denzer Ralf , Menzel Andreas , Ristinmaa Matti 
Published: February 2013

SUMMARYThis work deals with inverse‐motion‐based form finding for electroelasticity. The inverse motion problem is formulated for the electroelastic case, and the resulting equations are implemented within a finite element framework. A four‐field variational approach is adopted, taking into consideration the typically incompressible behavior of the elastomer materials commonly used in electromechanical applications. By means of numerical simulations, the inverse‐motion‐based form finding makes it possible to design the referential configuration so that a given set of loads and boundary conditions results in a prespecified deformed configuration. The computational finite element framework established in this work allows for such numerical simulations and testing and thereby the possibility to improve the design and accuracy in electroelastic applications such as grippers, sensors, and seals. Copyright © 2013 John Wiley & Sons, Ltd.
The obesity epidemic and changes in self‐report biases in BMI
Authors: Hattori Aiko , Sturm Roland 
Published: February 2013

AbstractObjective:To assess time trends in measurement error of BMI and the sensitivity/specificity of classifying weight status in the United States by analyzing the difference in BMI between self‐reported and measured height and weight.Design and Methods:Data from 18,394 respondents aged 20‐89 years from the National Health and Nutrition Examination Survey (NHANES) from 1999 through 2008 were analyzed. Multiple linear regression and logistic regression models estimated trends in reporting bias and misclassification of weight status by BMI categories, sex, age, and racial/ethnic groups, adjusting for the sampling design.Results:We find no evidence that there are time trends in the accuracy of self‐report by BMI categories, sex, age, or racial/ethnic groups. The well‐known downward bias in self‐report has remained stable over the last decade; approximately one in six to seven obese individuals were misclassified as nonobese due to underestimation of BMI.Conclusion:Increases in obesity rates based on self‐reported height and weight are likely to reflect actual weight increases and are not inflated by changes in reporting accuracy.
Intrahepatic lipid, not visceral or muscle fat, is correlated with insulin resistance in older, female rhesus macaques
Authors: Chu Michael P. , Klopfenstein Bethany J. , Krisky Christine M. , Urbanski Henryk F. , Rooney William D. , Kohama Steven G. , Purnell Jonathan Q. 
Published: February 2013

ObjectiveLittle is known of the effect of body composition on glucose metabolism in the aging female non‐human primate. These variables in older female Rhesus macaques were studied.Design and MethodsFemale Rhesus macaques (Macaca mulatta, n = 19, age range 23‐30 years) underwent magnetic resonance imaging and 1H spectroscopy to quantify total abdominal fat, visceral fat (VF), subcutaneous fat (SF) area, extramyocellular lipid (EMCL), intramyocellular lipid (IMCL) and intrahepatic lipid (IHL) content, and DEXA scan for whole body composition. A subgroup (n = 12) underwent a fasting blood draw and intravenous glucose tolerance test.ResultsSF correlated with homeostatic model assessment of insulin resistance (HOMAIR) and quantitative insulin sensitivity check index (QUICKI), but not after adjustment for fat mass. IHL demonstrated the strongest correlation with HOMAIR, QUICKI and calculated insulin sensitivity index (CSI), and remained significant after adjustment for fat mass. VF, IMCL, and EMCL did not correlate with any of our measures of insulin sensitivity.ConclusionsDespite a greater amount of VF compared to SF, VF was not associated with markers of insulin resistance (IR) in the older female monkey. Instead, IHL is a marker for IR in the fasting and post‐prandial state in these animals.
The influence of weight gain patterns in pregnancy on fetal growth using cluster analysis in an obese and nonobese population
Authors: Galjaard S. , Pexsters A. , Devlieger R. , Guelinckx I. , Abdallah Y. , Lewis C. , van Calster B. , Bourne T. , Timmerman D. , Luts J. 
Published: February 2013

ObjectiveExcessive weight gain during pregnancy has an important influence on fetal growth and on weight development in future generations.Design and MethodsA prospective cohort study of 325 obese and nonobese Caucasian women with naturally conceived, singleton pregnancies was performed. They were followed up until delivery for maternal weight gain and for fetal growth with ultrasound‐based weight estimations and final birth weight. Using cluster analysis distinct profiles of maternal weight gain during pregnancy were obtained. Longitudinal regression analysis was performed to investigate the relationship of the maternal weight gain profile and BMI on fetal growth and final birth weight.ResultsCluster analysis revealed four discernable maternal weight gain profiles: 12 cases (3.7%) ended up at their starting weight or decreased in weight (cluster 1), 16 cases (4.9%) who slightly increased in weight (maximum 4 kg) as compared to their initial weight (cluster 2), 114 cases (35.1%) who gained between 4 and 12 kg in weight (cluster 3), and 183 cases (56.3%) who showed the largest weight gain: more than 12 kg (cluster 4). There were statistically significant differences in fetal growth associated with weight gain cluster, which became apparent late in the second trimester and increased toward the end of pregnancy. Maternal BMI and maternal weight gain profile were independent predictors of fetal growth and birth weight.ConclusionsTherefore, the conclusion is that the cluster analysis permits to discern four gestational weight gain (GWG) patterns in obese and nonobese subjects and that both maternal BMI and maternal weight gain pattern during pregnancy positively influence fetal growth and birth weight.
Effects of risperidone on energy balance in female C57BL/6J mice
Authors: Li Xingsheng , Johnson Maria S. , Smith Daniel L. , Li Yan , Kesterson Robert A. , Allison David B. , Nagy Tim R. 
Published: February 2013

ObjectiveTo investigate the effect of risperidone on energy expenditure and weight gain in female C57BL/6J mice.Design and MethodsBody weight and composition, food intake, energy expenditure, and activity were determined weekly. mRNA expression of uncoupling protein 1 in brown adipose tissue, orexin, and brain‐derived neurotrophic factor in the hypothalamus were quantified using real‐time PCR.ResultsRisperidone tended to induce a greater body weight gain (P = 0.052) and significantly higher food intake (P = 0.038) relative to the placebo‐treated group. Risperidone‐treated mice had a higher resting energy expenditure (P = 0.001) and total energy expenditure (TEE) (P = 0.005) than the placebo group. There were no effects of treatment, time, and treatment by time on non‐resting (or activity‐related) energy expenditure between groups. Risperidone‐treated mice showed a significantly lesser locomotor activity than placebo‐treated mice over 3 weeks (P < 0.001). Risperidone induced a higher UCP1 mRNA (P = 0.003) and a lower orexin mRNA (P = 0.001) than placebo.ConclusionRisperidone‐induced weight gain is associated with hyperphagia and a reduction in locomotor activity in C57BL/6J mice. Additionally, higher total and resting energy expenditure were accompanied by higher levels of UCP1 mRNA in BAT. The increased TEE could not offset the total intake of energy through risperidone‐induced hyperphagia, therefore resulting in weight gain in female C57BL/6J mice.
Municipal Rebate Programs for Environmental Retrofits: An Evaluation of Additionality and Cost‐Effectiveness
Authors: Bennear Lori S. , Lee Jonathan M. , Taylor Laura O. 
Published: February 2013

AbstractWhen policies incentivize voluntary activities that also take place in the absence of the incentive, it is critical to identify the additionality of the policy—that is, the degree to which the policy results in actions that would not have occurred otherwise. Rebate programs have become a common conservation policy tool for local municipalities seeking to retrofit residential properties with efficient appliances. This research evaluates whether such rebates can be cost‐effective means for water utilities to promote water conservation. A unique database is developed that combines water‐use data over a three‐year period for all households that participated in a utility's high‐efficiency toilet (HET) rebate program, water‐use data for a matched sample of neighbors who did not receive a rebate, and a survey of rebate participants. Difference‐in‐differences models indicate that installation of an HET reduces household water consumption by approximately 7 percent. While installation of an HET appears to be an effective means for achieving household reductions in water consumption, our results also suggest that the rebate program is a much less effective means for achieving household reductions in water consumption. Specifically, the rebate program is found to provide limited additional water savings beyond what would have occurred naturally and is responsible for only 37 percent of the total water reduction attributable to the installation of HETs over the study period. © 2013 by the Association for Public Policy Analysis and Management.
Changing attitudes towards termination of pregnancy for trisomy 21 with non‐invasive prenatal trisomy testing: a population‐based study in Dutch pregnant women
Authors: Verweij E. J. (Joanne) , Oepkes Dick , de Boer Marjon A. 
Published: February 2013

What's already known about this topic?

Decision‐making in prenatal screening involves preparing for the potential diagnosis of Down syndrome (trisomy 21 or T21) and the choice for termination of pregnancy (TOP).What does this study add?

The results suggest that implementing non‐invasive prenatal testing may be associated with an increased uptake of prenatal testing, whereas the percentage of women who opt to terminate a pregnancy affected by trisomy 21(T21) may likely decrease.
Non‐invasive prenatal testing may not lead to a vast reduction in live births of children with T21, but unlike the current situation, most will be born in families who accepted, with or without testing, the chance of having and caring for a child with T21.
Dispersion of graphene nanoplatelets in poly(vinyl acetate) latex and effect on adhesive bond strength
Authors: Pinto Artur M , Martins Jorge , Moreira J. Agostinho , Mendes Adélio M. , Magalhães Fernão D. 
Published: February 2013

AbstractGraphene nanoplatelets (GNPs) were directly dispersed in poly(vinyl acetate) (PVAc) latex in concentrations from 0.05 up to 2 wt% (based on dry weight), without using additional surfactants or dispersants. Stable dispersions were obtained due to interaction of the GNPs with protective colloids (poly(vinyl alcohol) and hydroxyethylcellulose) originally present in the latex. This caused an increase in viscosity and accentuated the pseudoplastic behavior of the latex, as evidenced by rheological measurements. Cryo‐SEM imaging showed that individual nanoplatelets were present in the aqueous phase. The equilibrium contact angle for water on dry PVAc films increased by 13° upon incorporation of 0.1 wt% GNPs due to the nanofiller hydrophobicity. However, this increase was lower for higher loadings, probably due to the occurrence of GNP agglomeration. Bond strength measurements performed with an automated bonding evaluation system setup on veneer lap joints showed more than 50% shear strength increase with incorporation of only 0.1–0.3 wt% GNPs. At higher loadings the bond strength decreased, indicating less efficient nanofiller dispersion in the polymer matrix. Raman spectroscopy analysis confirmed that GNP agglomeration was more significant at higher loadings.
Grazing‐incidence transmission small angle X‐ray scattering from thin films of block copolymers
Authors: Mahadevapuram Nikhila , Strzalka Joseph , Stein Gila E. 
Published: February 2013

AbstractThin films of lamellar and cylindrical block copolymers are popular systems for low‐cost nanolithography. To be useful as nanoscale templates, the lamellae or cylinders must be oriented perpendicular to the substrate. Domain orientations are usually characterized by microscopy measurements of the film surface, but these techniques cannot detect tilted, bent, or tortuous domains in the film interior. We report a simple method to quantify out‐of‐plane disorder in thin films of block copolymers based on a variant of grazing‐incidence small angle X‐ray scattering (GI‐SAXS). A typical GI‐SAXS experiment illuminates the center of a substrate‐supported film at a grazing angle of incidence (near the film/substrate critical angle), and the strong reflected signal is interpreted with the distorted‐wave Born approximation. In a new approach, the beam footprint is moved to the far edge of the sample, allowing the acquisition of a transmission pattern. The grazing‐incidence transmission data are interpreted with the simple Born approximation, and out‐of‐plane defects are quantified through analysis of crystal truncation rods and partial Debye‐Scherrer rings. Significantly, this study demonstrates that grazing‐incidence transmission small angle X‐ray scattering can detect and quantify the buried defect structure in thin films of block copolymers. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
Computational design, construction, and characterization of a set of specificity determining residues in protein–protein interactions
Authors: Nagao Chioko , Izako Nozomi , Soga Shinji , Khan Samia Haseeb , Kawabata Shigeki , Shirai Hiroki , Mizuguchi Kenji 
Published: February 2013

AbstractProteins interact with different partners to perform different functions and it is important to elucidate the determinants of partner specificity in protein complex formation. Although methods for detecting specificity determining positions have been developed previously, direct experimental evidence for these amino acid residues is scarce, and the lack of information has prevented further computational studies. In this article, we constructed a dataset that is likely to exhibit specificity in protein complex formation, based on available crystal structures and several intuitive ideas about interaction profiles and functional subclasses. We then defined a “structure‐based specificity determining position (sbSDP)” as a set of equivalent residues in a protein family showing a large variation in their interaction energy with different partners. We investigated sequence and structural features of sbSDPs and demonstrated that their amino acid propensities significantly differed from those of other interacting residues and that the importance of many of these residues for determining specificity had been verified experimentally. Proteins 2012;. © 2012 Wiley Periodicals, Inc.