bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extraneuronal toxicity of Alzheimer's β‐amyloid peptide: Comparative study on vertebrate skeletal muscles
Authors: Mukhamedyarov Marat A. , Teplov Alexander Y. , Grishin Sergey N. , Leushina Alina V. , Zefirov Andrey L. , Palotás András 
Published: April 2011

AbstractIntroduction.Alzheimer's β‐amyloid peptide (βAP) is known to possess a wide range of toxic effects on neurons in vitro and in vivo; however, there is little information available regarding its impact on other excitable tissues such as skeletal muscles, which, apart from brain cells, are thought to also be targets of βAP.Methods.Utilizing the combination of electrophysiology and myography, we investigated whether βAP also impairs the functioning of myocytes in frogs and mice.Results.Although application of βAP in the range of 10−6 to 10−8 M induced depolarization of muscle fibers in both species, it impaired contractility in frogs but not in mice, by reducing endplate potential amplitude and increasing the threshold potential.Conclusions.Unchanged contractility in the mouse in the presence of βAP is due to a higher safety factor of neuromuscular transmission in mammals compared with amphibians. Possible clinical implications are discussed. Muscle Nerve, 2011.
An alternating direction method for linear‐constrained matrix nuclear norm minimization
Authors: Xiao Yun‐Hai , Jin Zheng‐Fen 
Published: April 2011

SUMMARYThe aim of the nuclear norm minimization problem is to find a matrix that minimizes the sum of its singular values and satisfies some constraints simultaneously. Such a problem has received more attention largely because it is closely related to the affine rank minimization problem, which appears in many control applications including controller design, realization theory, and model reduction. In this paper, we first propose an exact version alternating direction method for solving the nuclear norm minimization problem with linear equality constraints. At each iteration, the method involves a singular value thresholding and linear matrix equations which are solved exactly. Convergence of the proposed algorithm is followed directly. To broaden the capacity of solving larger problems, we solve approximately the subproblem by an iterative method with the Barzilai–Borwein steplength. Some extensions to the noisy problems and nuclear norm regularized least‐square problems are also discussed. Numerical experiments and comparisons with the state‐of‐the‐art method FPCA show that the proposed method is effective and promising. Copyright © 2011 John Wiley & Sons, Ltd.
A supervisor like me: Race, representation, and the satisfaction and turnover decisions of public sector employees
Authors: Grissom Jason A. , Keiser Lael R. 
Published: April 2011

AbstractStudies of race representation in public organizations illustrate the importance of bureaucrat race in determining client‐level outcomes. Building “upward” from this research, this study examines how supervisor race impacts outcomes for street‐level bureaucrats using data from a nationally representative sample of public schools. Employing multiple estimation methods, we find that, consistent with the predictions of representation theory, teachers report higher job satisfaction and turn over less often when supervised by an own‐race principal. We also find that race congruence impacts the tangible and intangible organizational benefits teachers receive, and, moreover, that race congruence impacts white and African American employees differently. Most troubling, we find evidence that black teachers earn substantially less in supplemental pay when they work for a white principal, even when compared to white teachers in the same school. © 2011 by the Association for Public Policy Analysis and Management.
Polyaniline‐modified cellulose nanofibrils as reinforcement of a smart polyurethane
Authors: Auad María L , Richardson Tara , Orts William J , Medeiros Eliton S , Mattoso Luiz HC , Mosiewicki Mirna A , Marcovich Norma E , Aranguren Mirta I 
Published: April 2011

AbstractSegmented polyurethanes exhibiting shape memory properties were modified by the addition of polyaniline (PANI)‐coated cellulose nanofibrils (CNFs). The two‐phase structure of the polymer is responsible for the material's ability to ‘remember’ and autonomously recover its original shape after being deformed in response to an external thermal stimulus. PANI was grown on the surface of the CNFs via in situ polymerization. Modified nanocrystals were added to the segmented polyurethane in concentrations ranging from 0 to 15 wt%. The changes in the material properties associated with the percolation of the coated fibrils appear at higher concentrations than previously observed for non‐modified CNFs, which suggests that fibril agglomeration is occurring due to the PANI coating. The shape memory behavior of the composites is maintained at about the same level as that of the unfilled polyurethane only up to 4 wt% of fibrils. At higher concentrations, the rigidity of the nanofibrils as well as their interaction with the hard‐segment phase and the increasing difficulty of dispersing them in the polymer collaborate to produce early breakage of the specimens when stretched at temperatures above the melting point of the soft segments. Copyright © 2010 Society of Chemical Industry
Effect of aluminum deposition and annealing on polymer‐based solar cell performance
Authors: Guralnick Brett W. , Seppala Jonathan E. , Mackay Michael E. 
Published: April 2011

AbstractPreviously we characterized the active layer in polymer‐based solar cells containing Poly(3‐hexylthiophene) with the electron acceptor Phenyl‐C61‐butyric acid methyl ester (PCBM) to find a thin, pure polymer layer at the air interface just after spin coating. In this study, we find that when the aluminum back electrode was thermally evaporated onto the active layer, at high enough rate, craters were found in the pure polymer layer. This was determined by dissolving the aluminum and characterizing the active layer with an atomic force microscope. Poor device performance was noted under this condition. However, if the aluminum was evaporated at a slower rate, resulting in a flat active layer surface and no crater formation, the efficiency more than doubled. A similar result is found if lithium fluoride (LiF) is deposited before aluminum evaporation and no craters were found even for the higher aluminum evaporation rate. So, it appears that LiF acts as a momentum shield to crater formation allowing superior device performance. If the active layer is annealed before deposition of the back electrode then, regardless of deposition rate, similar device performance is found. Again, in our previous study, it was found that annealing the active layer forced PCBM to the air interface which apparently also acts as a momentum shield. Annealing the device after aluminum deposition produces poorer performance than annealing before deposition. However, these devices have a better fill factor. Examining the active layer shows that it undergoes a buckling transition due to differences in the aluminum and active layers' thermal expansivities which reduces overall contact with the electrodes. However, whatever contact is made, is superior, accounting for the improved fill factor. If the buckling instability could be avoided then this processing procedure may be used in the future to manufacture even better devices than with any of the other annealing procedures. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Thermally stimulated luminescence in aluminium nitride crystals
Authors: Bickermann Matthias , Schuster Sebastian , Epelbaum Boris M. , Filip Octavian , Heimann Paul , Nagata Shunro , Winnacker Albrecht 
Published: April 2011

AbstractElectronic levels of point defects in aluminium nitride (AlN) bulk single crystals are evaluated using thermally stimulated luminescence (TSL). As the crystals were grown using AlN source material of different purity levels, the samples show different concentrations of silicon, oxygen, carbon, and (presumably) vacancies and vacancy complexes. In the TSL spectra, broad peaks are detected around 40–70 K, 100 K, 170 K, 220 K, 260 K, and 390 K. The corresponding activation energies were calculated using the Hoogenstraaten method to 8–35 meV, 40–70 meV, 150–215 meV, 130–180 meV, 150–190 meV, 80–170 meV, and 590–770 meV, respectively. TSL peak intensities are discussed in terms of chemical analysis of the samples. The results indicate that oxygen and silicon act as dominant electron traps in AlN. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Epitaxial upward transport of Al at the beginning of the Al‐induced layer exchange process
Authors: Birajdar Balaji , Antesberger Tobias , Stutzmann Martin , Spiecker Erdmann 
Published: April 2011

AbstractAl‐induced layer exchange (ALILE) and crystallization in a stack of amorphous Si (a‐Si, 100 nm)/Al (50 nm)/quartz substrate, annealed at 450 °C, have been investigated at different length scales by optical microscopy as well as analytical scanning and transmission electron microscopy. Significant lateral and vertical redistribution of Al was observed, yielding Al deficient dendritic cell centers surrounded by an about 10 µm wide Al excess zone containing epitaxial islands of “pushed‐up” Al whose number density and size decreases with increasing distance from the cell boundary. This new finding is likely to be a key step forward in the understanding of the complex redistribution of Al and Si during the ALILE process. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A taxonomy of model‐based testing approaches
Authors: Utting Mark , Pretschner Alexander , Legeard Bruno 
Published: April 2011

SUMMARYModel‐based testing (MBT) relies on models of a system under test and/or its environment to derive test cases for the system. This paper discusses the process of MBT and defines a taxonomy that covers the key aspects of MBT approaches. It is intended to help with understanding the characteristics, similarities and differences of those approaches, and with classifying the approach used in a particular MBT tool. To illustrate the taxonomy, a description of how three different examples of MBT tools fit into the taxonomy is provided. Copyright © 2011 John Wiley & Sons, Ltd.
Elastography of the uterine cervix: implications for success of induction of labor
Authors: Swiatkowska‐Freund M. , Preis K. 
Published: April 2011

AbstractObjectivesTo perform a preliminary investigation into the use of elastography for cervical assessment, in order to determine the effectiveness of this method for the evaluation of cervical consistency.MethodsElastography of the uterine cervix was performed in 29 patients before induction of labor, with tissue surrounding the internal os described using a numeric scale called the elastography index (EI). A color map from purple to red was produced with the hardest tissues displayed as purple and assigned a score of 0 points and progressively softer tissues displayed as blue (1 point), green (2 points), yellow (3 points) and red (4 points). The EI of tissue around the internal os, in the middle part of the cervical canal and around the external os were analyzed in relation to the success of induction of labor using the t‐test.ResultsThe mean EI of the internal os in the group of patients with successful induction of labor was 1.23, while in the group with failed induction of labor it was 0.39 (Student's t‐test, P = 0.024). No difference was found for the EI of the middle part of the cervical canal or for the EI of the external os in relation to the success of induction of labor (P > 0.05).ConclusionElastography of the uterine cervix may be an objective method for assessment of softening of tissue in the region of the internal os before induction of labor. Standardization of the cervical properties observed on elastography during pregnancy may help to guide the use of prostaglandins or oxytocin for induction of labor. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Evolution of cognition
Authors: van Horik Jayden , Emery Nathan J. 
Published: April 2011

AbstractRenewed interest in the field of comparative cognition over the past 30 years has led to a renaissance in our thinking of how cognition evolved. Here, we review historical and comparative approaches to the study of psychological evolution, focusing on cognitive differences based on evolutionary divergence, but also cognitive similarities based on evolutionary convergence. Both approaches have contributed to major theories of cognitive evolution in humans and non‐human animals. As a result, not only have we furthered our understanding of the evolution of the human mind and its unique attributes, but we have also identified complex cognitive capacities in a few large‐brained species, evolved from solving social and ecological challenges requiring a flexible mind. WIREs Cogni Sci 2011 2 621–633 DOI: 10.1002/wcs.144This article is categorized under:

Cognitive Biology > Evolutionary Roots of Cognition
Celsior Versus University of Wisconsin Preserving Solutions for Liver Transplantation: Postreperfusion Syndrome and Outcome of a 5‐Year Prospective Randomized Controlled Study
Authors: García‐Gil Francisco A. , Serrano María T. , Fuentes‐Broto Lorena , Arenas Juan , García José J. , Güemes Antonio , Bernal Vanesa , Campillo Ana , Sostres Carlos , Araiz Juan J. , Royo Pablo , Simón Miguel A. 
Published: April 2011

AbstractBackgroundCelsior solution (CS) is a high‐sodium, low‐potassium, low‐viscosity extracellular solution that has been used for liver graft preservation in recent years, although experience with it is still limited. We performed an open‐label randomized active‐controlled trial comparing CS with the University of Wisconsin solution (UW) for liver transplantation (LT), with a follow‐up period of 5 years.MethodsAdult transplant recipients (n = 102) were prospectively randomized to receive either CS (n = 51) or UW (n = 51). The two groups were comparable with respect to donor and recipient characteristics. The primary outcome measure was the incidence of postreperfusion syndrome (PRS). Secondary outcome measures included primary nonfunction (PNF) or primary dysfunction (PDF), liver retransplantation, and graft and patient survival. Other secondary outcome measures were days in the intensive care unit (ICU) and the rates of acute rejection, chronic rejection, infectious complications, postoperative reoperations, and vascular and biliary complications.ResultsIn all, 14 posttransplant variables revealed no significant differences between the groups. There were no cases of PNF or PDF. The incidence of PRS was 5.9% in the CS group and 21.6% in the UW group (P = 0.041). After reperfusion, CS revealed greater control of serum potassium (P = 0.015), magnesium levels (P = 0.005), and plasma glucose (P = 0.042) than UW. Respective patient survivals at 3, 12, and 60 months were 95.7, 87.2, and 82.0% for the CS group and 95.7, 83.3, and 66.6% for the UW group (P = 0.123).ConclusionsWhile retaining the same degree of safety and effectiveness as UW for LT, CS may yield postliver graft reperfusion benefits, as shown in this study by a significant reduction in the incidence of PRS and greater metabolic control.
Primary culture of neurospheres obtained from fetal mouse central nervous system and generation of inner ear hair cell immunophenotypes in vitro
Authors: Liu X-W , Sun J-W 
Published: April 2011

AbstractObjective:To investigate whether hair cell immunophenotypes can be derived from the central nervous system.Design:We established in vitro cell cultures from embryonic day 14.5 fetal rat brain tissue, and analysed changes in the immunohistochemical features of these cell cultures following differentiation.Result:The immature neural progenitors obtained from the fetal mouse central nervous system generated cell immunophenotypes which expressed epitopes of the hair cell marker proteins myosin VIIa and Brn-3c and the supporting cell marker pan-cytokeratin.Conclusion:Neural progenitors have the potential to differentiate into inner ear hair cell and supporting cell phenotypes, and thus may be a useful material for cell transplantation therapy aiming to replace damaged inner ear hair cells.
Public pension funding in practice
Authors: MUNNELL ALICIA H. , AUBRY JEAN-PIERRE , QUINBY LAURA 
Published: April 2011

AbstractPublic pension funding has recently become a front-burner policy issue in the wake of the financial crisis and given the pending retirement of large numbers of baby boomers. This paper examines the current funding of state and local pensions using a sample of 126 plans, estimating an aggregate funded ratio in 2009 of 78% using GASB accounting methods. Projections for 2010–2013 suggest that some continued deterioration is likely. Funded status can vary significantly among plans, and so the paper explores the influence of four types of factors: funding discipline, plan governance, plan characteristics, and the fiscal situation of the state. Judging the long-term health of plans requires more than just a snapshot of assets and liabilities, and so the paper examines how well plans are meeting their Annual Required Contributions and what factors influence whether they make them. The paper also addresses the controversy over what discount rate to use for valuing liabilities, concluding that using a riskless rate of return could help improve funding discipline but would need to be implemented in a manageable way. Finally, the paper assesses whether plans face a near-term liquidity crisis and finds that most have assets on hand to cover benefits over the next 15–20 years. The bottom line is that, like private investors, public plans have been hit hard by the financial crisis and their full recovery is dependent on the rebound of the economy and the stock market.
Thermo-mechanical analyses of beryllium compound refractive lens for NSLS-II beamline
Authors: Ravindranath V. , Sharma S. , Chubar O. , Cai Y. , Coburn S. 
Published: April 2011

In this paper we discuss the finite-element analysis (FEA) of a one-dimensional beryllium compound refractive lens (Be-CRL) that was undertaken to study the feasibility of installing the CRL in the Inelastic X-ray Scattering (IXS) beamline of National Synchrotron Light Source-II (NSLS-II) (a new state-of-the-art medium-energy third-generation storage ring). The current insertion device for this beamline is an IVU22-6m in-vacuum planar undulator delivering a total power of ~9 kW with a peak power density of ~90 kW/mrad2. Through analysis, based on calculation of spectral angular distribution of undulator radiation from IVU22, we determined that it is essential to install a 30 µm graphite filter upstream of the CRL in order to restrict the temperature rise in the CRL to 65°C for acceptable thermal strain.
Fatty acid production in genetically modified cyanobacteria
Authors: Liu Xinyao , Sheng Jie , Curtiss III Roy 
Published: April 2011

To avoid costly biomass recovery in photosynthetic microbial biofuel production, we genetically modified cyanobacteria to produce and secrete fatty acids. Starting with introducing an acyl–acyl carrier protein thioesterase gene, we made six successive generations of genetic modifications of cyanobacterium
Synechocystis
sp. PCC6803 wild type (SD100). The fatty acid secretion yield was increased to 197 ± 14 mg/L of culture in one improved strain at a cell density of 1.0 × 10
9
cells/mL by adding codon-optimized thioesterase genes and weakening polar cell wall layers. Although these strains exhibited damaged cell membranes at low cell densities, they grew more rapidly at high cell densities in late exponential and stationary phase and exhibited less cell damage than cells in wild-type cultures. Our results suggest that fatty acid secreting cyanobacteria are a promising technology for renewable biofuel production.
IT IS THE EYES AND NOT THE SIZE THAT MATTER
Authors: Strabac Zan 
Published: April 2011

ABSTRACT
The number of immigrants to Western Europe has been increasing, with immigration the subject of much controversy in contemporary Europe. In this article, we investigate the relationship between the size of the immigrant population, how natives perceive this size, and their anti-immigrant attitudes. We use data from the 2002/2003 European Social Survey covering 17 Western European countries, and we find that as a rule Western Europeans think that the immigrant population in their country is much larger than it actually is. The perceived size of an immigrant population has an impact on anti-immigrant prejudices, but the real size does not. Like many authors before us, we find that education reduces prejudice. However, we also find that around 10 percent of the total effect of education is a result of educated individuals' more accurate views about size of immigrant populations. In other words, the effect of education on prejudice is in part mediated by size perceptions.
Utility of Stool Sample–based Tests for the Diagnosis of Helicobacter pylori Infection in Children
Authors: Leal Yelda A , Cedillo‐Rivera Roberto , Simón J Abraham , Velázquez Juan R , Flores Laura L , Torres Javier 
Published: April 2011

ABSTRACTObjective:Helicobacter pylori antigen or DNA in stool are meant to detect the bacteria; however, in children the colonization of the gastric mucosa by H pylori is usually weak and fecal excretion of antigen or DNA varies considerably, challenging the utility of these tests in this age group. The aim of the present study was to carry out a systematic review and meta‐analysis to evaluate the performance of stool H pylori DNA and antigen tests for the diagnosis of infection in children.Methods:We conducted a systematic review and meta‐analysis to assess the accuracy of stool tests for diagnosis of H pylori infection in children. We searched PubMed, EMBASE, and LILACS databases. Selection criteria included participation of at least 30 children and the use of a criterion standard for H pylori diagnosis. In a comprehensive search, we identified 48 studies.Results:Regarding antigen‐detection tests, enzyme‐linked immunosorbent assay (ELISA) monoclonal antibodies showed the best performance, with sensitivity and specificity of 97%, positive likelihood ratio (LR+) of 29.9, and negative likelihood ratio (LR−) of 0.03. ELISA polyclonal antibodies had sensitivity of 92%, specificity of 93%, LR+ of 16.2, LR− of 0.09, and high heterogeneity (P < 0.0001). One‐step monoclonal antibody tests demonstrated sensitivity of 88%, specificity of 93%, LR+ of 10.6, and LR− of 0.11. For DNA detection, polymerase chain reaction–based test showed sensitivity of 80.8%, specificity of 98%, LR+ of 17.1, and LR− of 0.18.Conclusions:Detection of H pylori antigen in stools with ELISA monoclonal antibodies is a noninvasive efficient test for diagnosis of infection in children. One‐step tests showed low accuracy and more studies are needed to obtain a useful office‐based screening test. The available molecular tests are still unreliable.