bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of annealing time and temperature on the crystallinity and heat resistance behavior of injection‐molded poly(lactic acid)
Authors: Srithep Yottha , Nealey Paul , Turng Lih‐Sheng 
Published: August 2012

AbstractThe effects of annealing time and temperature on the crystallinity of injection‐molded poly(lactic acid) (PLA) were investigated using differential scanning calorimetry and wide‐angle x‐ray diffraction. Differential scanning calorimetry, tensile test, and dynamic mechanical analysis showed that an increase in crystallinity in the PLA parts from the annealing treatment offers several benefits such as a higher glass transition temperature, better heat resistance, and greater storage modulus and tensile strength. Based on the experimental data, the degree of crystallinity, annealing time, and annealing temperature were found to closely follow the time–temperature superposition relationship. Namely, a master curve could be constructed based on either the Williams–Landel–Ferry equation or the Arrhenius relationship by shifting the crystallinity isotherms in the logarithmic scale horizontally along the log‐time axis. This relationship provides a quantitative guideline for annealing postinjection‐molded PLA parts to improve the heat resistance and mechanical properties. An increase of over 17% and 26% in tensile strength was achieved at an annealing temperature of 80°C for 30 min and 65°C for 31 h, respectively. POLYM. ENG. SCI. 2013. © 2012 Society of Plastics Engineers
Personality dysfunction and social functioning in schizophrenia
Authors: Newton‐Howes Giles , Marsh Reginald 
Published: August 2012

ABSTRACTAimTo determine if personality dysfunction is associated with poorer clinical and social indicators in patients with schizophrenia.MethodologyAn observational study of patients with schizophrenia in psychiatric care assessed patient satisfaction with care, social functioning and psychopathology. Analysis of the relationship between personality and these three domains quantitatively assessed differences between patients with and without comorbid personality dysfunction. Diagnostic confounding was assessed using partial correlation coefficients.ResultsForty‐five patients with schizophrenia were studied. In the schizophrenia group, personality dysfunction correlated with poorer social functioning but not poorer satisfaction with care. Linear regression found that the relationship between poorer social functioning and personality disorder in schizophrenia remained, taking other diagnoses and age into account. Partial correlation coefficients confirmed that this was no related to an overlap between personality and schizophrenia symptoms in this sample.ConclusionPersonality dysfunction may negatively influence social functioning in patients with schizophrenia but does not appear to impact on patients' views of the care they receive. This is not due to the potential for diagnostic confounding between schizophrenia and personality disorder. Further research using larger samples is needed to confirm this association. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of stereocomplexation on the physicochemical behavior of PLA/PEG block copolymers in aqueous solution
Authors: Wu Xiaohan , Li Suming , Ghzaoui Abdeslam El 
Published: August 2012

AbstractA series of polylactide/poly(ethylene glycol) (PLA/PEG) block copolymers were synthesized by ring‐opening polymerization of L‐ or D‐lactide in the presence of mono‐ or di‐hydroxyl PEG. The effects of stereocomplexation on the physicochemical behavior of PLA/PEG copolymers in aqueous solution were investigated by varying the degree of stereocomplexation or PLLA/PEG to PDLA/PEG ratio. In mixture solutions of insoluble and soluble copolymers, stereocomplexation strongly affects the solubility of the copolymers. In mixture solutions of soluble copolymers, both the size and aggregation number (Nagg) of the aggregates vary as a function of the degree of stereocomplexation. It is suggested that the size variation of the aggregates with increasing the degree of stereocomplexation is dependent on Nagg changes which are determined by two effects: the self‐adjusting of the aggregates so as to minimize the free energy and thus to increase the Nagg, and the kinetics of aggregation which tend to form more aggregates and thus to decrease the Nagg. Combination of the two opposite effects well explains the diverse variations of Nagg and size of the aggregates as a function of the degree of stereocomplexation. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Synthesis and characterization of C60/polyaniline composites from interfacial polymerization
Authors: Wang Qiguan , Wang Sumin , Li Jianping , Moriyama Hiroshi 
Published: August 2012

AbstractC60/polyaniline (PANI) nanocomposites have been synthesized by the oxidative polymerization of aniline with ammonium peroxydisulfate in the presence of C60 by using an interfacial reaction. When compared with the pure PANI nanofibers from the similar process, the diameter of the obtained C60/PANI nanofibers was increased because of the encapsulation of C60 into PANI during aniline polymerization, which resulted from the charge‐transfer interactions between C60 and aniline fragment in PANI. In addition, the resulting C60/PANI nanocomposites synthesized from the low initial C60/aniline molar ratio (less than 1:25) showed the homogenous morphology composed of fiber network structures, which has an electrical conductivity as high as 1.1 × 10−4 S/cm. However, the C60/PANI nanocomposites from the higher initial C60/aniline molar ratio (more than 1:15) showed the nonuniformly distributed morphology, and the electrical conductivity was decreased to 3.5 × 10−5 S/cm. Moreover, the C60/PANI nanocomposites from the interfacial reaction showed a higher value of electrical conductivity than the mechanically mixed C60/PANI blends with the same C60 content, because of the more evenly distributed microstructures. FTIR, UV–vis, and CV data confirmed the presence of C60 and the significant charge‐transfer interactions in the resultant nanocomposites, which was responsible for the morphology development of the C60/PANI and the variation of the electrical conductivity. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Supporting ‘work‐related goals’ rather than ‘return to work’ after cancer? A systematic review and meta‐synthesis of 25 qualitative studies
Authors: Wells Mary , Williams Brian , Firnigl Danielle , Lang Heidi , Coyle Joanne , Kroll Thilo , MacGillivray Steve 
Published: August 2012

AbstractBackgroundThis study aimed to systematically review and synthesise qualitative studies of employment and cancer.MethodsA rigorous systematic review and meta‐synthesis process was followed. A total of 13 233 papers were retrieved from eight databases; 69 were deemed relevant following title and abstract appraisal. Four further publications were identified via contact with key authors. Screening of full texts resulted in the retention of 25 publications from six countries, which were included in the synthesis.ResultsStudies consistently indicate that for people with cancer, ‘work’ forms a central basis for self‐identity and self‐esteem, provides financial security, forms and maintains social relationships, and represents an individual's abilities, talents and health. Work is therefore more than paid employment. Its importance to individuals rests on the relative value survivors place on these constituent functions. The desirability, importance and subsequent interpretation of individuals' experience of ‘return to work’ appears to be influenced by the ways in which cancer affects these functions or goals of ‘work’. Our synthesis draws these complex elements into a heuristic model to help illustrate and communicate these inter‐relationships.ConclusionThe concept of ‘return to work’ may be overly simplistic, and as a result, misleading. The proposed benefits previously ascribed to ‘return to work’ may only be achieved through consideration of the specific meaning and role of work to the individual. Interventions to address work‐related issues need to be person‐centred, acknowledging the work‐related outcomes that are important to the individual. A conceptual and operational shift towards supporting survivors to identify and achieve their ‘work‐related goals’ may be more appropriate. Copyright © 2012 John Wiley & Sons, Ltd.
Protein folding rates and thermodynamic stability are key determinants for interaction with the Hsp70 chaperone system
Authors: Sekhar Ashok , Lam Hon Nam , Cavagnero Silvia 
Published: August 2012

AbstractThe Hsp70 family of molecular chaperones participates in vital cellular processes including the heat shock response and protein homeostasis. E. coli's Hsp70, known as DnaK, works in concert with the DnaJ and GrpE co‐chaperones (K/J/E chaperone system), and mediates cotranslational and post‐translational protein folding in the cytoplasm. While the role of the K/J/E chaperones is well understood in the presence of large substrates unable to fold independently, it is not known if and how K/J/E modulates the folding of smaller proteins able to fold even in the absence of chaperones. Here, we combine experiments and computation to evaluate the significance of kinetic partitioning as a model to describe the interplay between protein folding and binding to the K/J/E chaperone system. First, we target three nonobligatory substrates, that is, proteins that do not require chaperones to fold. The experimentally observed chaperone association of these client proteins during folding is entirely consistent with predictions from kinetic partitioning. Next, we develop and validate a computational model (CHAMP70) that assumes kinetic partitioning of substrates between folding and interaction with K/J/E. CHAMP70 quantitatively predicts the experimentally measured interaction of RNase HD as it refolds in the presence of various chaperones. CHAMP70 shows that substrates are posed to interact with K/J/E only if they are slow‐folding proteins with a folding rate constant kf <50 s−1, and/or thermodynamically unstable proteins with a folding free energy ΔG0UN ≥−2 kcal mol−1. Hence, the K/J/E system is tuned to use specific protein folding rates and thermodynamic stabilities as substrate selection criteria.
Influence of temperature on formation of perfect tau fragment fibrils using PRIME20/DMD simulations
Authors: Cheon Mookyung , Chang Iksoo , Hall Carol K. 
Published: August 2012

AbstractWe investigate the fibrillization process for amyloid tau fragment peptides (VQIVYK) by applying the discontinuous molecular dynamics method to a system of 48 VQIVYK peptides modeled using a new protein model/force field, PRIME20. The aim of the article is to ascertain which factors are most important in determining whether or not a peptide system forms perfect coherent fibrillar structures. Two different directional criteria are used to determine when a hydrogen bond occurs: the original H‐bond constraints and a parallel preference H‐bond constraint that imparts a slight bias towards the formation of parallel versus antiparallel strands in a β‐sheet. Under the original H‐bond constraints, the resulting fibrillar structures contain a mixture of parallel and antiparallel pairs of strands within each β‐sheet over the whole fibrillization temperature range. Under the parallel preference H‐bond constraints, the β‐sheets within the fibrillar structures are more likely to be parallel and indeed become perfectly parallel, consistent with X‐ray crystallography, at a high temperature slightly below the fibrillization temperature. The high temperature environment encourages the formation of perfect fibril structures by providing enough time and space for peptides to rearrange during the aggregation process. There are two different kinetic mechanisms, template assembly with monomer addition at high temperature and merging/rearrangement without monomer addition at low temperature, which lead to significant differences in the final fibrillar structure. This suggests that the diverse fibril morphologies generally observed in vitro depend more on environmental conditions than has heretofore been appreciated.
Phase 3 clinical trial investigating the effect of selenium supplementation in men at high‐risk for prostate cancer
Authors: Algotar Amit M. , Stratton M. Suzanne , Ahmann Frederick. R. , Ranger‐Moore James , Nagle Raymond B. , Thompson Patricia A. , Slate Elizabeth , Hsu Chiu H. , Dalkin Bruce L. , Sindhwani Puneet , Holmes Michael A. , Tuckey John A. , Graham David. L. , Parnes Howard L. , Clark Lawrence C. , Stratton Steven P. 
Published: August 2012

AbstractPURPOSEThis study was conducted to investigate the effect of Se supplementation on prostate cancer incidence in men at high risk for prostate cancer.METHODSA Phase 3 randomized, double‐blind, placebo‐controlled clinical trial was conducted in 699 men at high risk for prostate cancer (prostate specific antigen (PSA) >4 ng/ml and/or suspicious digital rectal examination and/or PSA velocity >0.75 ng/ml/year), but with a negative prostate biopsy. Participants were randomized to receive daily oral placebo (N = 232), 200 µg selenium (N = 234), or 400 µg selenium (N = 233) as selenized yeast. They were followed every 6 months for up to 5 years. The time to diagnosis of prostate cancer was compared between treatment groups using the Cox proportional hazards model.RESULTCompared to placebo, the hazard ratios [95% confidence intervals] for risk of developing prostate cancer in the selenium 200 µg/day or the selenium 400 µg/day group were 0.94 [0.52, 1.7] and 0.90 [0.48, 1.7], respectively. PSA velocity in the selenium arms was not significantly different from that observed in the placebo group (P = 0.18 and P = 0.17, respectively).CONCLUSIONSelenium supplementation appeared to have no effect on the incidence of prostate cancer in men at high risk. In conjunction with results of other studies, these data indicate that selenium supplementation may not have a role in prostate cancer chemoprevention. Prostate 73: 328–335, 2013. © 2012 Wiley Periodicals, Inc.
Management discipline
Authors: Forest Jerry J. 
Published: August 2012

AbstractConduct of operations (COO) concerns how work is performed in a manufacturing unit with the overall objective of producing repeated and desired results. COO reduces the likelihood of human error. The term discipline is often used to describe how to bring a consistent approach to various operations to minimize errors.This article introduces a new model of COO based on a Steven Covey performance model, where improved performance is a function of (a) knowing what to do, (b) knowing how to do it, and (c) wanting to do it. Our new model (described in this article) applies this Covey principle to facilitate operating disciple, engineering disciple, and management discipline. Each element of COO should be in place to produce consistent results and reduce human error. © 2012 American Institute of Chemical Engineers Process Saf Prog, 2012.
Diamond solution‐gated field effect transistors: Properties and bioelectronic applications
Authors: Dankerl Markus , Hauf Moritz V. , Stutzmann Martin , Garrido Jose A. 
Published: August 2012

AbstractSolution gate field‐effect transistors (SGFETs) based on diamond show great potential in biosensing and bioelectronics thanks to the advantageous combination of physical and chemical properties offered by this carbon material. In this contribution, we discuss fundamental aspects of diamond SGFETs as well as a number of important applications. We first demonstrate how the p‐type charge accumulation at the hydrogen‐terminated diamond surface can be controlled with an electrolyte gate, forming the basis of diamond SGFETs. For a proper understanding of the operation of the surface conductive diamond SGFETs, it is essential to consider the effect of such a hydrophobic surface on the structure of water at the diamond/electrolyte interface. The electronic transport in the p‐type surface conductive channel is studied with Hall‐effect experiments performed in an electrolyte in order to elucidate the limiting scattering mechanisms for carriers at the diamond surface. We present the fabrication and characterization of arrays of solution‐gated field effect transistors based on single crystalline diamond revealing attractive sensor properties such as high sensitivity and low electronic noise. These diamond SGFETs are investigated as sensors of pH and ionic strength of the electrolyte. Further, we demonstrate the use of these devices for the detection of neurotransmitters when the sensor's active area is functionalized with suitable enzymes. Finally, we show the application of diamond SGFETs for the extracellular recording of the electrical activity of electrogenic cells, thus paving the way for the development of novel diamond‐based bio‐hybrid systems with the potential to facilitate further progress in the understanding of the cell–semiconductor interface.
On covering expander graphs by hamilton cycles
Authors: Glebov Roman , Krivelevich Michael , Szabó Tibor 
Published: August 2012

AbstractThe problem of packing Hamilton cycles in random and pseudorandom graphs has been studied extensively. In this paper, we look at the dual question of covering all edges of a graph by Hamilton cycles and prove that if a graph with maximum degree Δ satisfies some basic expansion properties and contains a family of edge disjoint Hamilton cycles, then there also exists a covering of its edges by Hamilton cycles. This implies that for every α > 0 and every there exists a covering of all edges of G(n,p) by Hamilton cycles asymptotically almost surely, which is nearly optimal.Copyright © 2012 Wiley Periodicals, Inc. Random Struct. Alg., 44, 183‐200, 2014
A New Approach to Assess Gold Nanoparticle Uptake by Mammalian Cells: Combining Optical Dark‐Field and Transmission Electron Microscopy
Authors: Rosman Christina , Pierrat Sebastien , Henkel Andreas , Tarantola Marco , Schneider David , Sunnick Eva , Janshoff Andreas , Sönnichsen Carsten 
Published: August 2012

AbstractToxicological effects of nanoparticles are associated with their internalization into cells. Hence, there is a strong need for techniques revealing the interaction between particles and cells as well as quantifying the uptake at the same time. For that reason, herein optical dark‐field microscopy is used in conjunction with transmission electron microscopy to investigate the uptake of gold nanoparticles into epithelial cells with respect to shape, stabilizing agent, and surface charge. The number of internalized particles is strongly dependent on the stabilizing agent, but not on the particle shape. A test of metabolic activity shows no direct correlation with the number of internalized particles. Therefore, particle properties besides coating and shape are suspected to contribute to the observed toxicity.
The effects of tetanic stimulation on plasticity of remote synapses in the hippocampus‐perirhinal cortex‐amygdala network
Authors: Supcun Beste , Ghadiri Maryam Khaleghi , Zeraati Maryam , Stummer Walter , Speckmann Erwin‐Josef , Gorji Ali 
Published: August 2012

AbstractIn the temporal lobe, multiple synaptic pathways reciprocally link different structures. These multiple pathways play an important role in the integrity of the function of the temporal lobe and malfunction in this network has been suggested to underlie some neurological disorders such as epilepsy. To test whether the induction of long‐term potentiation (LTP) in one temporal lobe structure would modulate functional synaptic plasticity in other structures of this network, tetanic stimulation was applied to the white matter of the perirhinal cortex, Schaffer collaterals of the hippocampus, or the external capsule in combined rat amygdala–hippocampus–cortex slices. This tetanic stimulation was accompanied by enhancement of the evoked field potential slope in the third layer of perirhinal cortex, hippocampal CA1 area, and the lateral amygdala. Induction of LTP in each of these structures was concomitant with increased evoked field potentials in the neighboring structures. Surgical disconnection of anatomical pathways between these structures inhibited this concomitant enhancement of theevoked field potential slope. Both NMDA and AMPA glutamate sub‐receptors were involved in changes of synaptic plasticity elicited by induction of LTP in the neighboring structures. The present data indicate a reciprocal control among the perirhinal cortex, the amygdala, and the hippocampus plasticity. This could be important for the formation and retention of the medial temporal lobe‐dependent memory and may play a role in the involvement of all different regions of the temporal lobe in pathological conditions such as epilepsy that affect this brain structure. Synapse 66:965–974, 2012. © 2012 Wiley Periodicals, Inc.
5‐HT2A receptor blockade and 5‐HT2C receptor activation interact to reduce cocaine hyperlocomotion and fos protein expression in the caudate‐putamen
Authors: Pockros Lara A. , Pentkowski Nathan S. , Conway Sineadh M. , Ullman Teresa E. , Zwick Kimberly R. , Neisewander Janet L. 
Published: August 2012

AbstractBoth the 5‐HT2A receptor (R) antagonist M100907 and the 5‐HT2CR agonist MK212 attenuate cocaine‐induced dopamine release and hyperlocomotion. This study examined whether these drugs interact to reduce cocaine hyperlocomotion and Fos expression in the striatum and prefrontal cortex. We first determined from dose‐effect functions a low dose of both M100907 and MK212 that failed to alter cocaine (15 mg/kg, i.p.) hyperlocomotion. Subsequently, we examined whether these subthreshold doses given together would attenuate cocaine hyperlocomotion, consistent with a 5‐HT2A/5‐HT2CR interaction. Separate groups of rats received two sequential drug injections 5 min apart immediately before a 1‐h locomotion test as follows: (1) saline + saline, (2) saline + cocaine, (3) 0.025 mg/kg M100907 + cocaine, (4) 0.125 mg/kg MK212 + cocaine, or (5) cocktail combination of 0.025 mg/kg M100907 and 0.125 mg/kg MK212 + cocaine. Brains were extracted for Fos immunohistochemistry 90 min after the second injection. We next examined the effects of 0.025 mg/kg M100907 and 0.125 mg/kg MK212, alone and in combination, on spontaneous locomotor activity. While neither drug given alone produced any effects, the M100907/MK212 cocktail attenuated cocaine hyperlocomotion as well as cocaine‐induced Fos expression in the dorsolateral caudate‐putamen (CPu), but had no effect on spontaneous locomotion. The findings suggest that 5‐HT2ARs and 5‐HT2CRs interact to attenuate cocaine hyperlocomotion and Fos expression in the CPu, and that the CPu is a potential locus of the interactive effects between these 5‐HT2R subtypes on behavior. Further research investigating combined 5‐HT2AR antagonism and 5‐HT2CR agonism as a treatment for cocaine dependence is warranted. Synapse, 2012. © 2012 Wiley Periodicals, Inc.