bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fabrication and Properties of Reinforced Membranes Based on Sulfonated Poly(arylene ether sulfone) Copolymers for Proton‐Exchange Membrane Fuel Cells
Authors: Yu Duk Man , Yoon Kyungseok , Yoon Young Jun , Kim Tae‐Ho , Lee Jang Yong , Hong Young Taik 
Published: March 2012

AbstractReinforced membranes are prepared by incorporation of SPAES copolymers into electrospun LCP nonwovens with the aim to improve dimensional stability and tensile properties. Two types of copolymers with different degrees of sulfonation are chosen for fabricating the reinforced membranes. Proton conductivity, dimensional stability, and morphology of the reinforced membranes are studied and compared to those of pristine membranes. The reinforced membranes reduce dimensional change due to water swelling by approximately 45–50% and enhance the tensile strength by about a factor of two. The proton conductivity shows a decline in the reinforced membranes because the LCP nonwovens serve as a barrier for proton transport. The reinforced membranes exhibit an adequate performance for DMFC applications.
Chemical Synthesis of Carbon Materials With Intriguing Nanostructure and Morphology
Authors: Lu An‐Hui , Hao Guang‐Ping , Sun Qiang , Zhang Xiang‐Qian , Li Wen‐Cui 
Published: March 2012

AbstractIn the past decades, carbon materials retain great development because of their indispensable applications in energy storage and conversion, adsorption, catalysis, and others. The evidence is that a number of new structured carbon materials have been synthesized from molecular level, bottom‐up strategy. To date, it has been possible to synthesize carbon materials with defined nanostructure and morphology, tunable surface area, and pore size. In this review, we focus on discussing the recent development of chemically synthesized carbon materials with intriguing nanostructure and morphology. For convenience, these materials are grouped into four categories — 0D quantum dots and spheres; 1D fibers, tubes, and wires; 2D films and membranes; and 3D monolithic structure. In each category, materials synthesis strategies are discussed, whereas their applications are briefly touched. In the last section, we made a brief summary and discussed the future perspectives of carbon materials. We expect that this review not only summarizes the main achievements in this area, but also creates interdisciplinary activities in between carbon chemistry and other research areas.
Coverings and matchings in r‐partite hypergraphs
Authors: Altner Douglas S. , Brooks J. Paul 
Published: March 2012

AbstractRyser's conjecture postulates that for r ‐partite hypergraphs, τ ≤ (r ‐ 1)ν where τ is the covering number of the hypergraph and ν is the matching number. Although this conjecture has been open since the 1960s, researchers have resolved it for special cases such as for intersecting hypergraphs where r ≤ 5. In this article, we prove several results pertaining to matchings and coverings in r ‐partite intersecting hypergraphs. First, we prove that finding a minimum cardinality vertex cover for an r ‐partite intersecting hypergraph is NP‐hard. Second, we note Ryser's conjecture for intersecting hypergraphs is easily resolved if a given hypergraph does not contain a particular subhypergraph, which we call a “tornado.” We prove several bounds on the covering number of tornados. Finally, we prove the integrality gap for the standard integer linear programming formulation of the maximum cardinality r ‐partite hypergraph matching problem is at least r ‐ k where k is the smallest positive integer such that r ‐ k is a prime power. © 2012 Wiley Periodicals, Inc. NETWORKS, Vol. 2012
Optimal gossiping in geometric radio networks in the presence of dynamical faults
Authors: Clementi Andrea , Monti Angelo , Pasquale Francesco , Silvestri Riccardo 
Published: March 2012

AbstractWe study deterministic fault‐tolerant gossiping protocols in geometric radio networks. Node and link faults may happen during every time‐slot of the protocol's execution. We first consider the model where every node can send at most one message per time‐slot. We provide a protocol that completes gossiping in O(nΔ) time (where n is the number of nodes and Δ is the maximal in‐degree) and has message complexity O(n2). Both bounds are then shown to be optimal. Second, we consider the model where messages can be arbitrarily combined and sent in one time‐slot. We give a protocol working in optimal completion time O(DΔ) (where D is the maximal source eccentricity) and message complexity O(Dn). © 2012 Wiley Periodicals, Inc. NETWORKS, Vol. 2012
Distributed tree comparison with nodes of limited memory
Authors: Fusco Emanuele G. , Pelc Andrzej 
Published: March 2012

AbstractWe consider the task of comparing two rooted trees with port labels. Roots of the trees are joined by an edge and the comparison has to be performed distributedly, by exchanging messages among nodes. If the two trees are isomorphic, all nodes must finish in a state YES; otherwise they have to finish in a state NO and break symmetry, nodes of one tree getting label 0 and nodes of the other getting label 1. Nodes are modeled as identical automata, and our goal is to establish trade‐offs between the memory size of such an automaton and the efficiency of distributed tree comparison, measured either by the time or by the number of messages used for communication between nodes. We consider both the synchronous and the asynchronous communication and establish exact trade‐offs in both scenarios. For the synchronous scenario, we are concerned with memory versus time trade‐offs. We show that if the automaton hasxbits of memory, wherex≥clogn, for a small constantc, then the optimal time to accomplish the comparison task in the class of trees of size at mostnand of height at mosth> 1 is Θ(h+n/x). For the asynchronous scenario, we study memory versus number of messages trade‐offs. We show that if the automaton hasxbits of memory, wheren≥x≥clogn, then the optimal number of messages to accomplish the comparison task in the class of trees of size at mostnis Θ(n2/x). © 2012 Wiley Periodicals, Inc. NETWORKS, Vol. 2012
Ultrasonication‐assisted synthesis of molecularly imprinted polymer‐encapsulated magnetic nanoparticles for rapid and selective removal of 17β‐estradiol from aqueous environment
Authors: Xia Xinlong , Lai Edward P.C. , Ormeci Banu 
Published: March 2012

AbstractMolecularly imprinting technique was combined with magnetic nanoparticles to synthesize molecularly imprinted polymer‐encapsulated particles for selective removal and efficient separation of estrogenic compounds from water. The core‐shell‐structured particles were successfully prepared by a novel 2‐h ultrasonication‐assisted synthesis in a mixture of water and organic solvent using dual‐layer surfactant‐modified magnetic particles as core, the most physiologically active estrogenic compound (17β‐estradiol) as template, and widely adapted methacrylic acid as functional monomer. Ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, and magnetic separation were used to characterize the particles. High‐performance liquid chromatography–tandem mass spectrometry was used for quantitative binding performance analysis at low‐nanogram per milliliter levels. The particles exhibited satisfactory recognition of 17β‐estradiol in water. They possessed great potential for rapid, cost‐effective, and efficient separation of estrogenic compounds from aqueous environment with specificity. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
X‐ray diffraction and differential scanning calorimetry studies of a BaTiO3/polyvinylidene fluoride composites
Authors: Elzayat M.Y.F. , El‐Sayed S. , Osman H.M. , Amin M. 
Published: March 2012

AbstractBarium titanate/polyvinylidene fluoride (BaTiO3)x (PVDF)100–x composite samples were prepared and characterized using X‐ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques. In this work, the ratio of the constituents of this composite was altered, and the structural and thermal changes were studied. Also, the variation of tetragonality of BaTiO3 (BT) in the composite samples as a function of BT content was studied for the first time. The results show that all the samples are in the α‐phase, and the hindrance to the PVDF crystallization increases with the increase of BaTiO3 (BT) ratio in the composite. Tetragonal distortion of BT nanoparticles in the composite increases with the increase in BT ratio up to 30%, where it gets a saturation value. Also, it seems that stretching the samples enhances the BT tetragonality. Both melting and crystallization behaviors of the composite samples show double‐melting endotherms (reorganization) and crystallization exotherms. The inclusion of BT in the composite samples results in a decrease in the melting temperature of the samples. POLYM. ENG. SCI., 52:1945–1950, 2012. © 2012 Society of Plastics Engineers
Processing and mechanical properties of thermoplastic composites based on cellulose fibers and ethylene—acrylic acid copolymer
Authors: Ariño Ruth , Boldizar Antal 
Published: March 2012

AbstractThe melt processing and the tensile mechanical properties of composites consisting of 30 wt% softwood kraft pulp cellulose fibers and ethylene‐acrylic acid copolymer (EAA) with 7% acrylic acid content were studied. The compounding techniques used were extrusion mixing performed with a single screw extruder and elongation dispersive mixing performed with the injection‐molding machine. All blends were injection‐molded in a final step. Fiber length, fiber content, and mechanical properties were measured and the number and the size of the fiber aggregates were determined by microscopy analysis. It was concluded that two passes of elongation dispersive mixing had a beneficial effect on the mechanical properties, which could be related to the fewer and smaller amounts of aggregates. The different types of processing performed had a small or insignificant effect on the fiber length since the fiber lengths measured were within the same range as that of the starting material. POLYM. ENG. SCI., 52:1951–1957, 2012. © 2012 Society of Plastics Engineers
Identification of pesticide transformation products in agricultural soils using liquid chromatography/quadrupole‐time‐of‐flight mass spectrometry
Authors: Padilla‐Sánchez Juan A. , Michael Thurman E. , Plaza‐Bolaños Patricia , Ferrer Imma 
Published: March 2012

RATIONALEA study of pesticide transformation products (TPs) was carried out in soils of agricultural areas working under integrated pest management programs (IPMs). Bupirimate and cyromazine were the pesticides detected in soils after an initial pre‐screening. The aim of this work was the identification of relevant TPs of these two pesticides.METHODSSoil samples were extracted by pressurized liquid extraction (PLE), using a mixture of ethyl acetate/methanol (3:1, v/v), and analyzed by ultra‐high‐pressure liquid chromatography coupled to hybrid quadrupole‐time‐of‐flight mass spectrometry (UHPLC‐QTOF‐MS). For confirmation purposes, tandem mass spectrometry (MS2) experiments were carried out using QTOF‐MS, obtaining specific fragment structures of the pesticides and their degradates.RESULTSRetention times and exact masses of the protonated molecules were used for the identification of the pesticides bupirimate (m/z 317.1642) and cyromazine (m/z 167.1040) and their respective TPs, namely ethirimol (m/z 210.1601) and melamine (m/z 127.0727). A novel strategy using pseudo‐MS3 experiments was developed to confirm the structure of bupirimate TP (ethirimol). This strategy consists of generating the particular TP in the ion source, via collision‐induced fragmentation, and then performing MS/MS to the fragment ion formed in‐source.CONCLUSIONSEthirimol and melamine were identified as degradation products of bupirimate and cyromazine, respectively. The study was applied to the analysis of 15 agricultural soil samples finding bupirimate and ethirimol in seven samples, cyromazine in one sample and melamine in four samples. Copyright © 2012 John Wiley & Sons, Ltd.
When does incentive compensation motivate managerial behaviors? An experimental investigation of the fit between incentive compensation, executive core self‐evaluation, and firm performance
Authors: Chng Daniel Han Ming , Rodgers Matthew S. , Shih Eric , Song Xiao‐Bing 
Published: March 2012

AbstractWe develop and test an integrative model that examines the fit between compensation schemes, executives' characteristics, and situational factors. We propose that a fit among all three factors is crucial to motivate desirable managerial behaviors. Using a specially designed management simulation, our study demonstrates that the effectiveness of incentive compensation to motivate managerial behaviors depends on executives' core self‐evaluation and firm performance. Our results show that, relative to fixed salary compensation, executives with higher core self‐evaluation respond to incentive compensation with greater perseverance, competitive strategy focus, ethical behavior, and strategic risk taking during organizational decline. However, these interaction effects are not present during organizational growth. Our theory and empirical evidence provide significant insights into the complex relationships among compensation schemes, executives' characteristics, firm performance, and managerial behaviors. Copyright © 2012 John Wiley & Sons, Ltd.
The effects of energy drink in combination with alcohol on performance and subjective awareness
Authors: Alford Chris , Hamilton-Morris Jennifer , Verster Joris C. 
Published: March 2012

Abstract

Rationale
This study investigated the coadministration of an energy drink with alcohol to study the effects on subjective intoxication and objective performance.

Objectives
This study aims to evaluate the objective and subjective effects of alcohol versus placebo at two alcohol doses, alone and in combination with an energy drink, in a balanced order, placebo-controlled, double-blind design.

Methods
Two groups of ten healthy volunteers, mean (SD) age of 24 (6.5), participated in the study. One group consumed energy drink containing 80 mg of caffeine and the other consumed a placebo drink, with both receiving two alcohol doses (0.046 and 0.087% breathalyser alcohol concentration). Tests included breath alcohol assessment, objective measures of performance (reaction time, word memory and Stroop task) and subjective visual analogue mood scales.

Results
Participants showed significantly impaired reaction time and memory after alcohol compared to the no alcohol condition and had poorer memory after the higher alcohol dose. Stroop performance was improved with the energy drink plus alcohol combination compared to the placebo drink plus alcohol combination. Participants felt significant subjective dose-related impairment after alcohol compared to no alcohol. Neither breath alcohol concentration nor the subjective measures showed a significant difference between the energy drink and the placebo energy drink when combined with alcohol.

Conclusions
Subjective effects reflected awareness of alcohol intoxication and sensitivity to increasing alcohol dose. There were no overall significant group differences for subjective measures between energy drink and placebo groups in the presence of alcohol and no evidence that the energy drink masked the subjective effects of alcohol at either dose.
Role of chemotherapy in treatments for biliary tract cancer
Authors: Furuse Junji , Kasuga Akiyoshi , Takasu Atsuko , Kitamura Hiroshi , Nagashima Fumio 
Published: March 2012

AbstractThe purpose of chemotherapy in patients with advanced solid cancers, including biliary tract cancer, is generally to improve the survival and quality of life of the patients. Also, adjuvant chemotherapy is expected to increase the curability of surgery in patients scheduled to undergo surgery. Most patients with unresectable biliary tract cancer develop obstructive jaundice, and biliary drainage is needed before any of the aforementioned treatments. Once jaundice is resolved by stenting of the bile duct or bilio‐intestinal bypass, cholangitis often develops, leading to rapid deterioration of the patient's general condition. Therefore, the beneficial effect of chemotherapy in such patients remains controversial. A few randomized controlled trials have demonstrated the survival benefit of chemotherapy as compared with supportive care. In one of these trials, improvement of the quality of life was also confirmed. Recently, since the survival benefit of combined gemcitabine plus cisplatin therapy over gemcitabine alone has been demonstrated in randomized controlled clinical trials, this combined regimen has been recognized as a standard therapy for unresectable biliary tract cancer. A second‐line regimen is now expected to be established for patients with gemcitabine‐refractory biliary tract cancer, although the significance of second‐line therapy remains unclear. One of the next issues in relation to chemotherapy for biliary tract cancer is the development of molecular‐targeted agents; however, few large clinical trials of such agents have been conducted for biliary tract cancer. Various issues in chemotherapy for biliary tract cancer remain to be investigated, and global cooperation is necessary to conduct large clinical trials.
Plasma succinylacetone is persistently raised after liver transplantation in tyrosinaemia type 1
Authors: Bartlett David C. , Preece Mary Anne , Holme Elisabeth , Lloyd Carla , Newsome Phil N. , McKiernan Patrick J. 
Published: March 2012

AbstractBackgroundTyrosinaemia type 1 (HT1) is a rare disorder leading to accumulation of toxic metabolites such as succinylacetone (SA) and a high risk of hepatocellular carcinoma. Children with HT1 traditionally required liver transplantation (OLT) and while the need for this has been reduced by the introduction of nitisinone some still require OLT. SA inhibits the enzyme porphobilinogen (PBG) synthase and its activity can be used as a marker of active SA. Elevated urinary SA post OLT has been reported previously. This study describes a novel finding of elevated plasma SA following OLT for HT1.MethodsA retrospective analysis was performed of patients treated for HT1 at our institution from 1989‐2010.ResultsThirteen patients had an OLT for HT1. In patients who received nitisinone prior to OLT, mean urinary and plasma SA were elevated prior to treatment but normalised by the time of OLT (p ≤ 0.01). Mean PBG synthase activity increased from 0.032 to 0.99 nkat/gHb (ref range 0.58‐1.25) at the time of OLT (p < 0.01). Mean urinary SA in patients not treated with nitisinone was also elevated prior to OLT; plasma levels and PBG synthase activity were not available prior to OLT for this group. Following OLT, mean urinary and plasma SA were elevated in all for the duration of follow‐up and associated with low‐normal PBG synthase activity.ConclusionUrinary and plasma SA levels are elevated following OLT for HT1. Low‐normal PBG synthase activity suggests the plasma SA may be active. The clinical significance of this is unclear.
Preparation and Surface Activities of Modified Double‐Tailed Anionic Surfactants
Authors: Lin Li‐Huei , Liu Hsin‐Jiant , Chu Hawn‐Chung , Dong Min‐Yan , Hwang Mou‐Chuan , Wang Chien‐Fu , Chen Keng‐Ming 
Published: March 2012

AbstractWe prepared a series of modified double‐tailed surfactants containing two identical nonionic moieties and an anionic spacer group. Each surfactant was prepared through the reaction of two moles of polyoxyethylene alkyl ether with one mole of maleic anhydride to form a diester having a gemini structure; an anionic sulfonate group was then introduced through reaction of the olefinic bond with sodium hydrogen sulfite. The structures of these compounds were confirmed through infrared spectroscopy, nuclear magnetic resonance spectroscopy, and elemental analysis. These modified double‐tailed surfactants exhibit good surface properties, including low‐foaming, wetting and lime‐soap dispersing power. Their excellent dispersing abilities toward disperse dyes were due to the double‐tailed structures of the surfactants, with the hydrophobic moieties increasing the binding ability to the dyes and its anionic units providing dispersing power.
Mechanisms Underlying Decreased Hepatic Triacylglycerol and Cholesterol by Dietary Bitter Melon Extract in the Rat
Authors: Senanayake Gamarallage V. K. , Fukuda Nobuhiro , Nshizono Shoko , Wang Yu‐Ming , Nagao Koji , Yanagita Teruyoshi , Iwamoto Masako , Ohta Hideaki 
Published: March 2012

AbstractIn these studies, we focused on finding the mechanism(s) underlying the bitter melon (Momordica charantia L.) methanol fraction (MF)‐dependent reduction in the concentration of hepatic triacylglycerol (TAG) and cholesterol in the rat. Rats were fed diets containing low (5 %) fat for 2 weeks (experiment 1), or low (5 %) and high (15 %) fat for a longer period of 8 weeks (experiment 2). MF was supplemented at 1 % level in both experiments. After feeding, rats were sacrificed, and their livers were prepared as slices and hepatocytes, followed by incubation with [1(2)‐14C] acetate or [1‐14C] oleic acid (18:1 n‐6). Under these conditions, we found that rats fed diets containing MF, as compared to those without MF, showed: (1) no adverse effects on food intake and growth, (2) a decreased hepatic TAG and total cholesterol, irrespective of the difference in dietary fat level or feeding period, and (3) a decreased incorporation of [1(2)‐14C] acetate and [1‐14C] oleic acid into TAG of liver slices and hepatocytes. MF‐supplemented rats also showed no altered incorporation of labeled acetate into cholesterol and cholesterol ester, an increased fecal excretion of neutral steroids, but not of acidic steroids, and an enhanced mRNA abundance of carnitine palmitoylacyltransferase I, which is the rate‐limiting enzyme for fatty acid oxidation. These results suggest that dietary MF decreases hepatic TAG synthesis while enhancing fatty acid oxidation, thereby reducing the concentration of hepatic TAG. The liver cholesterol‐lowering effect of MF, however, is probably mediated through an increased fecal excretion of neutral steroids, without an effect on cholesterogenesis.
Implementation of an Intraoperative Clinical Experience for Senior Level Baccalaureate Nursing Students
Authors: Mott Jason 
Published: March 2012

AbstractPerioperative nursing is a specialty that has been eliminated from many nursing education programs. With the loss of perioperative clinical experiences, the number of students pursuing a career in perioperative nursing after graduation has declined. A faculty member at one Midwestern school of nursing developed and implemented a perioperative clinical experience for senior‐level baccalaureate nursing students in a critical care nursing course. This program, developed with the assistance of four local hospitals and the college of nursing, included an eight‐hour OR orientation and 56 clinical hours. Students were placed in the OR under preceptor guidance and supervision. Feedback from evaluations was positive and provided recommendations for improving the program, in particular, to allow more clinical hours and more hands‐on experience for the students.