bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of the Dispersion Quality in Polymer Nanocomposites by Rheological Methods
Authors: Galindo‐Rosales Francisco J. , Moldenaers Paula , Vermant Jan 
Published: January 2011

AbstractThe properties of filled polymers and nanocomposites are strongly linked to the adequate dispersion of the solid phase into a polymeric matrix. However, obtaining the degree of dispersion within a polymer composite system is far from trivial. Typical methods for microstructural analysis such as electron and optical microscopy or scattering methods only investigate the local microstructure. In addition they are either labor intensive or may yield data that are difficult to analyze. Methods that focus more strongly on the end‐use properties, such as conductivity or bulk moduli, offer a global view of the material performance, but are of course post factum. The rheological properties of (nano)particle filled matrices in the molten state offer a cost‐effective alternative to evaluate the dispersion quality and can even be used during a production process. Moreover, it does not necessitate optical transparency, adequate scattering contrast, or conductivity. Typically, rheological data have been mainly used in qualitative terms and it is as yet unclear if the quality of dispersion can be quantified. The present work contains a systematic evaluation of methods to characterize the dispersion quality from rheology. Using a well‐defined model sample it is shown how the dispersion quality can be assessed quantitatively by studying the viscoelastic properties as a function of volume fraction. Moreover, a novel method is proposed, where the time evolution of the linear and nonlinear rheological properties at a fixed volume fraction is studied and analyzed. magnified image
Effects of carbon nanotubes on glass transition and crystallization behaviors in immiscible polystyrene/polypropylene blends
Authors: Wu Jun , Xiang Fangming , Han Liang , Huang Ting , Wang Yong , Peng Ya , Wu Haiyan 
Published: January 2011

AbstractFunctionalized multiwalled carbon nanotubes (FMWCNTs) have been introduced into immiscible polystyrene/polypropylene (PS/PP) blends. Not only the change in glass‐transition temperatures of PS and PP but also the crystallization and melting behaviors of PP have been investigated. The results show that FMWCNTs exhibit dual effects in the blends. One is that FMWCNTs, as a plasticizer for both PS and PP, induce the change in glass‐transition behaviors in both PS and PP. The other is that FMWCNTs, as a heterogeneous nucleating agent for PP, change the crystallization behavior of PP from homogeneous/bulk crystallization process to only bulk crystallization process. Further results show that the presence of FMWCNTs also induces the morphology change of the immiscible blends to a certain degree. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Preparation and characterization of hybrid membranes for fuel cell applications: hydrogenated styrene–butadiene rubber filled with alkyl, phenyl or tolyl sulfonated silica
Authors: Garcia Escribiano Pilar , Cánovas Maria J , Ojeda Maria C , del Río Carmen , Sánchez Félix , Acosta Jose L 
Published: January 2011

AbstractPolymers with ionic groups attached (ionomers) are indispensable electrolyte materials for proton exchange membrane fuel cells. Nafion®, a widely used membrane, has many disadvantages: price, high methanol crossover and conductivity loss at temperatures above 80 °C. This work reports the preparation and characterization of hybrid membranes, alternatives to commercial Nafion, based on blends of hydrogenated polybutadiene‐block‐polystyrene copolymer and organophilized silicas. The films obtained were crosslinked to improve mechanical stability, and heterogeneously sulfonated to convert them to proton‐conducting systems. Structural characterization involved differential scanning calorimetry and dynamic mechanical analysis to determine their thermal and mechanodynamical transitions, attenuated total reflectance Fourier transform infrared spectroscopy for verifying the introduction of sulfonic groups and scanning electron microscopy linked with energy‐dispersive X‐ray analysis for obtaining more information on the location and distribution of silica within the polymer matrix. Electrical characterization was made using electrochemical impedance spectroscopy, giving high conductivity values of ca 2.6–5.8 × 10−2 S cm−1. Also, methanol crossover was determined: low permeabilities were found. The results showed that sulfonation of the styrene rings had occurred effectively. Conductivities were higher and methanol crossover lower than for Nafion for all samples. Copyright © 2011 Society of Chemical Industry
Atomic force microscopy study of self‐assembly behaviors of hydrophobic poly(n‐butyl methacrylate)‐block‐polydimethylsiloxane‐block‐poly(n‐butyl methacrylate) ABA triblock copolymers
Authors: Wang Huanbing , Tao Qingsheng , Wang Jinfang , Khoshdel Ezat 
Published: January 2011

AbstractPoly(n‐butyl methacrylate)‐block‐polydimethylsiloxane‐block‐poly(n‐butyl methacrylate) (PBMA‐block‐PDMS‐block‐PBMA) ABA triblock copolymers were synthesized successfully via atom‐transfer radical polymerization using PDMS as macroinitiator. The effects of PDMS content and substrate nature on self‐assembly behaviors of PBMA‐block‐PDMS‐block‐PBMAs were systematically studied using atomic force microscopy. Two series of triblock copolymers with different molecular weights and compositions, i.e. PBMA‐block‐PDMSA12‐block‐PBMAs and PBMA‐block‐PDMSA21‐block‐PBMAs, were used, where the latter were of a higher PDMS content than the former. On silicon wafer, it was found that only spherical structures formed after annealing films spin‐coated from chloroform solutions of PBMA‐block‐PDMSA12‐block‐PBMAs. In contrast, films of PBMA‐block‐PDMSA21‐block‐PBMAs formed semi‐continuous structures. On mica wafer, it was found that ordered cylindrical pores formed after annealing films spin‐coated from chloroform solutions of PBMA‐block‐PDMSA12‐block‐PBMAs. In contrast, films of PBMA‐block‐PDMSA21‐block‐PBMAs formed isolated cylinders or worm‐like morphologies. Copyright © 2011 Society of Chemical Industry
Assessing and treating child anxiety in schools
Authors: Mychailyszyn Matthew P. , Beidas Rinad S. , Benjamin Courtney L. , Edmunds Julie M. , Podell Jennifer L. , Cohen Jeremy S. , Kendall Philip C. 
Published: January 2011

AbstractAnxiety disorders in youth are common and, if left untreated, can lead to a variety of negative sequelae. Randomized clinical trials have demonstrated that cognitive‐behavioral therapy (CBT) is an efficacious treatment for anxiety disorders in youth with preliminary evidence showing that CBT can be successfully transported into schools. The present article provides (a) a discussion of the inherent challenges and advantages of implementing CBT in the school setting, (b) methods used to identify anxious youth, and (c) key components of CBT for anxious youth with an emphasis on adaptation and application in the school environment. Future research directions are discussed. The successful integration of a flexible CBT approach into the domain of school mental health would be a favorable step toward effective dissemination and would ensure the enduring provision of evidence‐based practice to children and adolescents struggling with anxiety. © 2011 Wiley Periodicals, Inc.
Assessing and treating aggression and conduct problems in schools: Implications from the Coping Power program
Authors: Powell Nicole P. , Boxmeyer Caroline L. , Baden Rachel , Stromeyer Sara , Minney Jessica A. , Mushtaq Asia , Lochman John E. 
Published: January 2011

AbstractChildren with high levels of aggressive behavior and conduct problems create major management problems in school settings and interfere with the learning environment of their classmates and with their own academic achievement. A contextual social‐cognitive model can provide a framework for understanding risk factors involved in the development and maintenance of aggression and conduct problems in children. The model also outlines important areas for intervention, including family factors, peer relationships, classroom and neighborhood factors, and children's social‐cognitive functioning. Evidence‐based, cognitive‐behavioral intervention and prevention programs for aggression and conduct problems have been developed to address risk factors that occur within the family, the school setting, and children's social‐cognitive processes. This article will review several evidence‐based, cognitive‐behavioral programs appropriate for children in preschool through late elementary school. We will also discuss how cognitive‐behavioral programs can be disseminated to school staff, and we will present important considerations in the selection of intervention and prevention programs. © 2011 Wiley Periodicals, Inc.
Assessment and intervention for adolescents with anger and aggression difficulties in school settings
Authors: Feindler Eva L. , Engel Emily C. 
Published: January 2011

AbstractThe development, implementation, and evaluation of anger management programs have proliferated over the past decade. The programs aim to moderate the intensity, frequency, and severity of anger expression, and facilitate alternative nonaggressive responses to conflict and frustration. Cognitive‐behavioral theory highlights cognitive processes such as attributions, expectations, interpersonal beliefs, and problem solving as most influential in determining an individual's response to provocation and identifies anger arousal as a mediator of aggressive behavior. Based on this premise that youth exhibit aggressive behavior due to poor arousal management, social, and problem‐solving skills, Feindler and colleagues have developed psychoeducational anger management programs to target these deficits and to teach prosocial, conflict resolution skills. This article will review the development of anger difficulties, suggest tools for screening and outcome assessment, describe the anger management intervention approach, and present an overview of the research supporting implementation in school and community settings. Finally, specific recommendations for implementation are provided. © 2011 Wiley Periodicals, Inc.
Band‐gap engineering of polythiophenes via dithienophosphole doping
Authors: Krüger Robin A. , Gordon Terry J. , Sutherland Todd C. , Baumgartner Thomas 
Published: January 2011

AbstractA series of polythiophenes doped with dithieno[3,2‐b:2′,3′‐d]phosphole units at varying levels (0–17%) were synthesized and characterized. Polymer work up provided two series of polymers from chloroform (C) and hexanes (H) for each doping level, respectively. Systematic structure–property studies revealed that the C‐series polymers generally had higher molecular weights than the H‐series, but also slightly higher relative dithienophosphole concentrations, both having a significant impact on the photophysical and electrochemical properties of the polymers. Furthermore, the presence of the dithienophosphole units also stabilizes the LUMO levels, whereas the HOMO levels remain dominated by the thiophene units, resulting in desirable electronics for an interaction with acceptor materials, such as 1‐(3‐methoxycarbonyl)propyl‐1‐phenyl[6,6]C61. Importantly, increasing amount of dithienophosphole doping results in increased conductivities for the polymers in their oxidized state, while concurrently significantly stabilizing the neutral polythiophenes toward oxidation under environmental conditions. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Solvent‐tunable colors in imprinted helical structures on polymer template via multiple UV‐induced polymerization
Authors: Liu Jui‐Hsiang , Fang Hao , Chien Chih‐Chieh 
Published: January 2011

AbstractA solvent tunable single‐layer polymer film with a multipitched photonic structure as a new photonic band gap material has been developed by imprinting the helical structures on polymer matrices through multiple photocrosslinking in an induced chiral nematic mesophase. Here, the polymer matrices themselves served as a chiral template, which exhibited Bragg reflections in the absence of both a chiral dopant and anisotropic materials because of the memory effects of the polymer network. Tuning of colors was achieved by making a refractive index contrast in the two periodic media of imprinted solid helical structure and the isotropic liquids that fill it. On incorporation of various isotropic liquids in the imprinted matrices, a sharp peak in the reflection spectrum shifted drastically, which indicated that the wavelength shifts strongly depended on the sort of liquids that filled the matrices. The effects of temperature on the imprinted polymer template feeding the various liquids were studied through the reflectance spectra. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Israeli and Chinese partners of women with breast cancer: a cross‐cultural view of marital issues
Authors: Woloski‐Wruble Anna C. , Dekeyzer Ganz Freda , Jiang Yongqin , Qiang Wan‐Min , Kadmon Ilana 
Published: January 2011

AbstractObjective: Cultural nuances may influence the interface between the cancer experience and marital issues, specifically for the partner. Most of the literature has focused on the woman's narrative or couple's adjustment to cancer in general. The purpose of this study was to describe and compare the marital relationship, sexuality, and marital adjustment of Israeli and Chinese husbands of women with breast cancer and the discussion of the health‐care team concerning these issues.Methods: A convenience sample of 50 Chinese and 50 Israeli men, ages of 28–79 years, completed components of the Psychological Adjustment to Illness Scale, the Locke Wallace Adjustment Scale, and a background questionnaire.Results: The majority of husbands were in their first marriage. The average time since diagnosis was 16.7 months. No significant difference was found between the two groups on issues of marital relationship. Significant differences were found between Israeli and Chinese husbands on sexual interest, pleasure, and performance (p<0.05). Israeli husbands reported a significantly higher level of marital adjustment as opposed to the Chinese husbands (p = 0.006). Marital adjustment for both groups was significantly related only to perceived quality of the relationship (p<0.03).Conclusions: Significant cultural differences were found in sexuality variables with no differences discerned on marital relationship variables. Couple‐based interventions for marital issues are a critical component of support for both partners. Culturally sensitive assessment and care of the spouse as well as the woman with breast cancer should be part of a holistic, comprehensive family care plan. Copyright © 2011 John Wiley & Sons, Ltd.
Structure and mechanism of Escherichia coli glutathionylspermidine amidase belonging to the family of cysteine; histidine‐dependent amidohydrolases/peptidases
Authors: Pai Chien‐Hua , Wu Hsing‐Ju , Lin Chun‐Hung , Wang Andrew H.‐J. 
Published: January 2011

AbstractThe bifunctional Escherichia coli glutathionylspermidine synthetase/amidase (GspSA) catalyzes both the synthesis and hydrolysis of Gsp. Its amidase domain (GspA), which catalyzes the hydrolysis of Gsp into glutathione and spermidine, plays an important role in redox sensing and protein S‐thiolation. To gain insight of the regulation and catalytic mechanism of and further understand the recycling of the Gsp dimer and Gsp‐S‐protein adducts, we solved two crystal structures of GspA and GspSA both with the C59A mutation and bound with the substrate, Gsp. In both structures, Cys59, His131, and Glu147 form the catalytic triad, which is similar to other cysteine proteases. Comparison of the GspA_Gsp complex and apo GspSA structures indicates that on binding with Gsp, the side chains of Asn149 and Gln58 of the amidase domain are induced to move closer to the carbonyl oxygen of the cleaved amide bond of Gsp, thereby participating in catalysis. In addition, the helix‐loop region of GspA, corresponding to the sequence 30YSSLDPQEYEDDA42, involves in regulating the substrate binding. Our previous study indicated that the thiol of Cys59 of GspA is only oxidized to sulfenic acid by H2O2. When comparing the active site of GspA with those of other cysteine proteases, we found that limited space and hydrophobicity of the environment around Cys59 play an important role to inhibit its further oxidation. The structural results presented here not only elucidate the catalytic mechanism and regulation of GspA but also help us to design small molecules to inhibit or probe for the activity of GspA.
Time‐dependent solution of molecular quantum systems using multiwavelet
Authors: Hamada Shinji , Sekino Hideo 
Published: January 2011

AbstractWe solve the time‐dependent Schrödinger equation (TDSE), time‐dependent Hartree‐Fock equations (TDHF), and time‐dependent Density Functional Theory DFT(TDDFT) [Runge and Gross, Phys Rev Lett 1984, 52, 997] equations of general electronic/muonic systems using a multiresolution multiwavelet (MRMW) basis set. The stable solution of these timedependent equations with relatively large time step is obtained using the Cayley formalism with the MRMW basis set. The Cayley operator corresponding to each axis is applied to the direct‐product basis set or a subset of the direct‐product basis set to obtain high efficiency for multidimensional cases. The method is tested by applications to the simulation of electron and muon dynamics of simple molecular systems in the framework of Ehrenfest dynamics employing classical point charge nucleus approximation. Stable solutions of the equations for the quantum and classical particles are obtained. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Surgical technique enhances the efficiency of robotic hysterectomy
Authors: Feuer Gerald , Hernandez Patricia , Barker James 
Published: January 2011

AbstractBackgroundThe purpose of this study was to evaluate the benefits and morbidity associated with a novel technique for a hysterectomy designed specifically for a robotic‐assisted laparoscopic procedure. Recent studies have compared robotic‐assisted laparoscopic hysterectomy vs. open hysterectomy. We have developed a surgical technique that has enabled us to efficiently decrease the standard operative time.MethodsAll patients (55) underwent a robotic‐assisted hysterectomy utilizing a novel surgical technique with four specific components, inclusive of the Hem‐o‐lok® locking clip.ResultsThis surgical technique has enabled us to efficiently decrease the standard operative time to an average of 80.9 ± 3.44 min with an estimated blood loss of 63.5 ± 3.76 ml and a hospital stay of 1.3 ± 0.15 days, with minimal complications during surgery (1.8%).ConclusionWe have provided an efficient technique that is safe, easily reproducible and comparable to open hysterectomy operation times. Copyright © 2011 John Wiley & Sons, Ltd.
Evaluation of a neurosurgical robotic system to make accurate burr holes
Authors: Brodie James , Eljamel Sam 
Published: January 2011

AbstractIntroductionNeurosurgery has been driven forward by the latest breakthroughs in technology that combine science and engineering. Neurosurgical robotic systems are a good example of such a breakthrough that has several potential advantages over existing techniques. This study sought to evaluate the Pathfinder robotic system in order to establish whether it is capable of carrying out burr hole procedures in specific locations in human skull replicas, along predetermined trajectories and for precise depths.MethodsThree different registration fiducial configurations (A, B and C) were used on three different skull replicas of patients obtained from CT scan reconstructions. The skull replicas were scanned and the PathFinder robotic arm was used to place burr holes along specific trajectories. Target registration accuracies for surface targets and burr hole placements were measured, and the burr hole depths and trajectories were assessed.ResultsOverall registration errors, surface target registration accuracies, and burr hole target registration accuracies were submillimetric in all three registration fiducial configurations. However, the accuracies recorded in configurations B and C were significantly better than those in configuration A.ConclusionResults demonstrated that the robotic system can approach surface and burr hole targets accurately. The accuracy was altered significantly by the configuration of registration fiducials and the robot was a useful tool to steady the surgical drill to place burr holes in specific locations and depth along the programmed trajectory. Copyright © 2011 John Wiley & Sons, Ltd.
Organo bifunctional silane effects on the vibration, thermal, and mechanical properties of a vinyl‐group‐containing silicone rubber/natural rubber/silica compound
Authors: Nga Dang Thi To , Kim Jin Kuk , Kim Kwang‐Jea 
Published: January 2011

AbstractA bifunctional silane (TESPD) was added to a vinyl‐group‐containing silicone rubber (SR)/natural rubber (NR)/silica compound, and the resulting mechanical, morphological, and thermal properties were compared with those of an NR/silica compound. The addition of TESPD to the silica‐filled SR/NR compound formed an SR‐silane‐silica‐silane‐NR structure that behaved as a ter‐polymer. The addition of SR into the NR improved the mechanical properties (torque maximum, modulus, elongation at break, and hardness) and thermal properties as well as the tan δ values. The SR‐silane‐silica‐silane‐NR structure exhibited advanced properties that are suitable for an automotive engine mount application, which requires good thermal and vibration absorption properties. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers
In Vitro Intestinal Bioaccessibility of Alkylglycerols Versus Triacylglycerols as Vehicles of Butyric Acid
Authors: Martín Diana , Morán‐Valero María I. , Señoráns Francisco J. , Reglero Guillermo , Torres Carlos F. 
Published: January 2011

AbstractButyric acid has been the subject of much attention last years due to its bioactivity. However, the potential advantages of butyrate are limited by the problem to reach enough plasma concentrations; therefore, pro‐drugs have been proposed as an alternative to natural butyrate. A comparative study on in vitro intestinal digestion of 2,3‐dibutyroil‐1‐O‐octadecyl glycerol (D‐SCAKG) and tributyrin (TB), as potential pro‐drugs of butyric acid, was performed. Aliquots were taken at different times of digestion for studying the extent and rate of hydrolysis of both substrates. The micellar phase (MP) and oily phase (OP) formed in the digestion media were separated and their composition in lipid products was analyzed. Initially, it was confirmed that the in vitro model reproduced physiological results by testing against olive oil as a standard lipid. The progress of in vitro intestinal digestion of D‐SCAKG was slower than that of TB. TB hydrolyzed completely to butyric acid, whereas D‐SCAKG mainly yielded 2‐butyroil‐1‐O‐octadecyl glycerol (M‐SCAKG), followed by butyric acid and 1‐O‐octadecyl glycerol (AKG). The MP from both substrates mainly consisted of butyric acid. Minor levels of M‐SCAKG and AKG were also found in the MP after hydrolysis of D‐SCAKG, the M‐SCAKG being mainly distributed in the OP. Therefore, D‐SCAKG produced a stable form of esterified butyric acid as M‐SCAKG after in vitro intestinal digestion, unlike TB. Additionally, such a product would integrate both bioactive compounds, butyric acid and alkylglycerol, within the same molecule. Free butyric acid and AKG would be also released, which are lipid products of interest as well.