bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of thermally conducting phase‐change materials based on polyethylene/wax blends filled with copper particles
Authors: Molefi J. A. , Luyt A. S. , Krupa I. 
Published: January 2010

AbstractThis article reports on the morphology, melting and crystallization behavior, thermal stability, tensile properties, and thermal conductivity of phase‐change materials (PCM) for thermal energy storage. These materials were based on a soft Fischer‐Tropsch paraffin wax (PCM) blended with low‐density polyethylene, linear low‐density polyethylene, and high‐density polyethylene. These immiscible blends were melt‐mixed with copper (Cu) microparticles (up to 15 vol %) to improve the thermal conductivity in the matrix material. The presence of the Cu microparticles in the PCMs did not significantly change the crystallization behavior, thermal stability, or tensile properties of the blend composites in comparison with the corresponding polyethylene/wax blends and polyethylene/Cu composites. The observed differences were related to the fact that the wax seemed to have a higher affinity for the Cu particles than any of the polyethylenes, and so it crystallized as a layer around the Cu particles. The thermal conductivity of the samples increased almost linearly with increasing Cu content, but the samples had slightly lower values than the corresponding polyethylene/Cu composites, probably because of the lower thermal conductivity of the wax. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Renewable elastomers based on blends of maleated polypropylene and plasticized starch
Authors: DeLeo Candice , Goetz James , Young Brian , Velankar Sachin S. 
Published: January 2010

AbstractMost recent developments in polymers from renewable resources have focused on thermoplastics, whereas there has been no comparable development of plastics with elastomeric properties. Here we evaluate the possibility of developing renewable elastomers based on starch. Potato starch plasticized with glycerol (called plasticized starch, or PLS) was melt‐blended with small quantities (5 wt % or 15 wt%) of maleated polypropylene (MAPP). The maleic anhydride groups of the polypropylene are expected to react with the hydroxy groups of starch under melt blending conditions. The resulting blends of MAPP and PLS were characterized by mechanical testing, SEM, DMA, and DSC. SEM, solubility and adhesion tests indicate that the blends are two‐phase materials, in which the continuous phase PLS is physically crosslinked by polypropylene domains. The materials showed rubbery properties as judged by a low glass transition temperature (∼−50°C independent of polypropylene content), and a wide rubbery plateau in DMA experiments that extended from room temperature to as high as 170°C. The tensile properties are also characteristic of elastomers. However, slow aging due to starch crystallization, and extraction of glycerol upon water exposure remain two challenges that must be overcome before the materials can be used as practical elastomers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and properties of carbon fiber/ hydroxyapatite‐poly(methyl methacrylate) biocomposites
Authors: Jianfeng Huang , Juanying Li , Liyun Cao , Liping Zeng 
Published: January 2010

AbstractAn in situ polymerization with a later solution co‐mixing approach was used in the preparation of polymethyl methacrylate (PMMA) matrix composites using hydroxyapatite (HA) nanoparticles and short carbon fibers(C(f)) as reinforcing materials. The microstructures and fracture surface morphologies of the prepared C(f)/HA‐PMMA composite were characterized using XRD, FTIR, SEM, EDS, and FESEM analyses. The mechanical properties of the composites were tested by a universal testing machine. Results show that the surface of nitric acid‐oxidized carbon fibers and lecithin‐treated HA contain new functional groups. Uniform dispersion of short fibers and HA nanoparticles in PMMA matrix is successfully achieved and the mechanical properties of the composites are obviously improved. The flexural strength, flexural modulus, and Young's modulus of the composites reach the maximum value 128.12 MPa, 1.150 GPa, and 4.572 GPa when carbon fiber and HA mass fraction arrive to 4% and 8%, respectively. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Relating microhardness to injection molding induced morphology: A study of microbeam synchrotron WAXD
Authors: Kobayashi Yutaka , Kanno Hiroaki , Hanamoto Yasuhiro , Ando Makoto , Kanai Toshitaka 
Published: January 2010

AbstractThe relationship between microhardness and morphology of polypropylene near the surface of injection molded plaques was investigated. Crystal structures and molecular orientation from the surface to shear oriented layer were characterized by microbeam synchrotron wide angle X‐ray diffraction, polarizing optical microscope and Fourier transformed infrared spectroscopy. From precise measurements, using an X‐ray beam with width of 0.35 μm, the frozen layer was divided into two layers. Molecular and crystal orientations changed greatly in the surface layer but remained constant in the inner layer. These oriented morphology did not affect microhardness along the depth direction on the cross‐cut surface. Microhardness was proportional to crystallinity and showed a local maximum at shear oriented layer and a minimum at the surface. Then, positional dependence of microhardness was compared at the gate and the center of the plaque. Although crystallinity near the gate was lower than that at the center position, microhardness was higher. Therefore, crystallinity mainly affects microhardness but superstructure like cross‐hatching lamellae which is induced in biaxially extended melt flow is also not neglected in injection molded polypropylene parts. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Photoisomerization behavior of bisbenzylidene and 1,3,4‐oxadiazole‐based liquid crystalline polyesters
Authors: Balamurugan R. , Kannan P. 
Published: January 2010

AbstractPhotoisomerization behavior of bisbenzylideneacetone/cycloheptanone and 1,3,4‐oxadiazole containing nematic liquid crystalline polyesters under UV irradiation was investigated. Solubility, carbonyl group absorption band in FTIR, optical microscopy observation, as well as DSC analysis through existence of liquid crystallinity after irradiation were proved this phenomenon. Fluorescence spectra revealed blue‐emission maxima with Stokes shift in the range of 46–49 nm. Band gap energy calculated from absorption spectra are in the range of 3.18–3.41 eV. Structure–property relationships were probed by correlating the spacer length with development of mesophase formation, thermal, and optical properties. Optical property of polymers disclosed photoisomerization processes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Statistical thermal stability of PVC
Authors: Savrık Sevdiye Atakul , Erdoğan Beyhan Cansever , Balköse Devrim , Ülkü Semra 
Published: January 2010

AbstractExperimental design was used to optimize the processing parameters for the decomposition of poly(vinyl chloride). Factorial design and face centered composite design (FCC) were applied to determine the optimum conditions. A total of 10 g PVC powder was mixed with different amounts of zinc stearate (ZnSt2) and natural zeolite and tested for thermal stability. Factorial fitted model was explained by first order pattern due to the significant main effect regression constants, and FCC model was described by second order model owing to higher order polynomial coefficients. FCC design was superior to factorial design as FCC considers not only its pure quadratic effects contribution but also its higher overall desirability for thermal stability of PVC. For factorial design the optimum conditions were determined as 163.06 mg for ZnSt2, 399.99 mg for zeolite, and 140°C for temperature with desirability of 0.933. However, 400 mg for ZnSt2, 333.24 mg for zeolite, and 140°C for temperature with desirability of 0.956 were obtained as the optimum conditions by FCC design. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
5‐Stabilized Phosphatidylinositol 3,4,5‐Trisphosphate Analogues Bind Grp1 PH, Inhibit Phosphoinositide Phosphatases, and Block Neutrophil Migration
Authors: Zhang Honglu , He Ju , Kutateladze Tatiana G. , Sakai Takahiro , Sasaki Takehiko , Markadieu Nicolas , Erneux Christophe , Prestwich Glenn D. 
Published: January 2010

AbstractMetabolically stabilized analogues of PtdIns(3,4,5)P3 have shown long‐lived agonist activity for cellular events and selective inhibition of lipid phosphatase activity. We describe an efficient asymmetric synthesis of two 5‐phosphatase‐resistant analogues of PtdIns(3,4,5)P3, the 5‐methylene phosphonate (MP) and 5‐phosphorothioate (PT). Furthermore, we illustrate the biochemical and biological activities of five stabilized PtdIns(3,4,5)P3 analogues in four contexts. First, the relative binding affinities of the 3‐MP, 3‐PT, 5‐MP, 5‐PT, and 3,4,5‐PT3 analogues to the Grp1 PH domain are shown, as determined by NMR spectroscopy. Second, the enzymology of the five analogues is explored, showing the relative efficiency of inhibition of SHIP1, SHIP2, and phosphatase and tensin homologue deleted on chromosome 10 (PTEN), as well as the greatly reduced ability of these phosphatases to process these analogues as substrates as compared to PtdIns(3,4,5)P3. Third, exogenously delivered analogues severely impair complement factor C5a‐mediated polarization and migration of murine neutrophils. Finally, the new analogues show long‐lived agonist activity in mimicking insulin action in sodium transport in A6 cells.
Selective Palladium‐Catalyzed Dehydrogenation of Limonene to Dimethylstyrene
Authors: Horrillo‐Martínez Patricia , Virolleaud Marie‐Alice , Jaekel Christoph 
Published: January 2010

AbstractConditions for the selective dehydrogenation of (+)‐limonene 1 to the polymer building block dimethylstyrene 2 are described. The reaction occurs smoothly in the presence of Pd(OTFA)2 as catalyst and CuCl2 as oxidant. High selectivity for retaining the exocyclic double bond during aromatization is achieved (>14:1). Initially, variable‐temperature NMR experiments, under stoichiometric conditions, showed a stepwise formation of a π‐allyl intermediate and subsequent reaction to give a mixture of products. However, kinetic experiments showed a sigmoidal curve, pointing to the heterogeneous nature of the catalytically active species. A number of experiments were undertaken to differentiate between homogeneous, molecularly defined catalysis and heterogeneous, nanocluster‐based catalysis. Based on the results, it is proposed that the true catalytic system is heterogeneous in nature.
Influence of Support Hydroxides on the Catalytic Activity of Oxidized Gold Clusters
Authors: Veith Gabriel M. , Lupini Andrew R. , Pennycook Stephen J. , Dudney Nancy J. 
Published: January 2010

AbstractGold oxide nanoparticles were prepared on the native surface and a hydroxylated surface of a nonporous TiO2 support (Degussa P25). Scanning transmission electron microscopy shows the formation of similarly sized clusters on both support materials (1.86 and 1.61 nm clusters on the native oxide and the hydroxylated oxide respectively). X‐ray absorption near‐edge spectroscopy and X‐ray photoelectron spectroscopy clearly indicate the formation of Au3+‐rich oxide nanoparticles. Despite the similar cluster sizes and oxidation states, the gold oxide clusters grown on the hydroxylated surface were at least 180 times more catalytically active for the oxidation of carbon monoxide than those grown on the native oxide surface. Thus hydroxides, which are incidentally introduced during the solution‐phase synthesis of gold catalysts, appear to play a dominant, but previously largely unrecognized, role in the catalytic properties of both oxidized and metallic gold particles.
ChemInform Abstract: Synthesis of cis‐Vinyltrimethylstannanes and cis‐Vinylpinacolboronates in a Two‐Step Highly Regio and Stereoselective Process.
Authors: Mirzayans Paul Malek , Pouwer Rebecca H. , Williams Craig M. , Bernhardt Paul V. 
Published: January 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Conomicidines A and B, Unusual Alkaloid—Hydroxycinnamyl Alcohol Conjugates from Tabernaemontana corymbosa
Authors: Lim Kuan‐Hon , Kam Toh‐Seok 
Published: January 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Raman Spectroscopy of Strained Single‐Walled Carbon Nanotubes
Authors: Liu Zhongfan , Zhang Jin , Gao Bo 
Published: January 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Functional Genomics for Plant Natural Product Biosynthesis
Authors: Yonekura‐Sakakibara Keiko , Saito Kazuki 
Published: January 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Two‐Dimensional Infrared Spectroscopy of Metal Carbonyls
Authors: Baiz Carlos R. , Mcrobbie Porscha L. , Anna Jessica M. , Geva Eitan , Kubarych Kevin J. 
Published: January 2010

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Space‐time cluster identification in point processes
Authors: Assunçäo Renato , Tavares Andréa , Correa Thais , Kulldorff Martin 
Published: January 2010

AbstractThe authors propose a new type of scan statistic to test for the presence of space‐time clusters in point processes data, when the goal is to identify and evaluate the statistical significance of localized clusters. Their method is based only on point patterns for cases; it does not require any specific knowledge of the underlying population. The authors propose to scan the three‐dimensional space with a score test statistic under the null hypothesis that the underlying point process is an inhomogeneous Poisson point process with space and time separable intensity. The alternative is that there are one or more localized space‐time clusters. Their method has been implemented in a computationally efficient way so that it can be applied routinely. They illustrate their method with space‐time crime data from Belo Horizonte, a Brazilian city, in addition to presenting a Monte Carlo study to analyze the power of their new test.
A new family of random graphs for testing spatial segregation
Authors: Ceyhan Elvan , Priebe Carey E. , Marchette David J. 
Published: January 2010

AbstractThe authors discuss a graph‐based approach for testing spatial point patterns. This approach falls under the category of data‐random graphs, which have been introduced and used for statistical pattern recognition in recent years. The authors address specifically the problem of testing complete spatial randomness against spatial patterns of segregation or association between two or more classes of points on the plane. To this end, they use a particular type of parameterized random digraph called a proximity catch digraph (PCD) which is based on relative positions of the data points from various classes. The statistic employed is the relative density of the PCD, which is a U‐statistic when scaled properly. The authors derive the limiting distribution of the relative density, using the standard asymptotic theory of U‐statistics. They evaluate the finite‐sample performance of their test statistic by Monte Carlo simulations and assess its asymptotic performance via Pitman's asymptotic efficiency, thereby yielding the optimal parameters for testing. They further stress that their methodology remains valid for data in higher dimensions.
Marginalized transition random effect models for multivariate longitudinal binary data
Authors: Ilk Ozlem , Daniels Michael J. 
Published: January 2010

AbstractGeneralized linear models with random effects and/or serial dependence are commonly used to analyze longitudinal data. However, the computation and interpretation of marginal covariate effects can be difficult. This led Heagerty (1999, 2002) to propose models for longitudinal binary data in which a logistic regression is first used to explain the average marginal response. The model is then completed by introducing a conditional regression that allows for the longitudinal, within‐subject, dependence, either via random effects or regressing on previous responses. In this paper, the authors extend the work of Heagerty to handle multivariate longitudinal binary response data using a triple of regression models that directly model the marginal mean response while taking into account dependence across time and across responses. Markov Chain Monte Carlo methods are used for inference. Data from the Iowa Youth and Families Project are used to illustrate the methods.
Cramér‐von Mises statistics for discrete distributions with unknown parameters
Authors: Lockhart Richard A. , Spinelli John J. , Stephens Michael A. 
Published: January 2010

AbstractChoulakian, Lockhart & Stephens (1994) proposed Cramér‐von Mises statistics for testing fit to a fully specified discrete distribution. The authors give slightly modified definitions for these statistics and determine their asymptotic behaviour in the case when unknown parameters in the distribution must be estimated from the sample data. They also present two examples of applications.
Bayesian analysis of elapsed times in continuous‐time Markov chains
Authors: Ferreira Marco A. R. , Suchard Marc A. 
Published: January 2010

AbstractThe authors consider Bayesian analysis for continuous‐time Markov chain models based on a conditional reference prior. For such models, inference of the elapsed time between chain observations depends heavily on the rate of decay of the prior as the elapsed time increases. Moreover, improper priors on the elapsed time may lead to improper posterior distributions. In addition, an infinitesimal rate matrix also characterizes this class of models. Experts often have good prior knowledge about the parameters of this matrix. The authors show that the use of a proper prior for the rate matrix parameters together with the conditional reference prior for the elapsed time yields a proper posterior distribution. The authors also demonstrate that, when compared to analyses based on priors previously proposed in the literature, a Bayesian analysis on the elapsed time based on the conditional reference prior possesses better frequentist properties. The type of prior thus represents a better default prior choice for estimation software.
Empirical likelihood inference for the regression model of mean quality‐adjusted lifetime with censored data
Authors: Zhao Yichuan , Wang Hongkun 
Published: January 2010

AbstractThe authors consider the empirical likelihood method for the regression model of mean quality‐adjusted lifetime with right censoring. They show that an empirical log‐likelihood ratio for the vector of the regression parameters is asymptotically a weighted sum of independent chi‐squared random variables. They adjust this empirical log‐likelihood ratio so that the limiting distribution is a standard chi‐square and construct corresponding confidence regions. Simulation studies lead them to conclude that empirical likelihood methods outperform the normal approximation methods in terms of coverage probability. They illustrate their methods with a data example from a breast cancer clinical trial study.
Optimal scaling of Metropolis algorithms: Heading toward general target distributions
Authors: Bédard Mylène , Rosenthal Jeffrey S. 
Published: January 2010

AbstractThe authors provide an overview of optimal scaling results for the Metropolis algorithm with Gaussian proposal distribution. They address in more depth the case of high‐dimensional target distributions formed of independent, but not identically distributed components. They attempt to give an intuitive explanation as to why the well‐known optimal acceptance rate of 0.234 is not always suitable. They show how to find the asymptotically optimal acceptance rate when needed, and they explain why it is sometimes necessary to turn to inhomogeneous proposal distributions. Their results are illustrated with a simple example.
On probability matching priors
Authors: Staicu Ana‐Maria , Reid Nancy M. 
Published: January 2010

AbstractFirst‐order probability matching priors are priors for which Bayesian and frequentist inference, in the form of posterior quantiles, or confidence intervals, agree to a second order of approximation. The authors show that the matching priors developed by Peers (1965) and Tibshirani (1989) are readily and uniquely implemented in a third‐order approximation to the posterior marginal density. The authors further show how strong orthogonality of parameters simplifies the arguments. Several examples illustrate their results.
Clinical impact of phosphorylated signal transducer and activator of transcription 3, epidermal growth factor receptor, p53, and vascular endothelial growth factor receptor 1 expression in resected adenocarcinoma of lung by using tissue microarray
Authors: Kim Hyeong Su , Park Yeon Hee , Lee Jeeyun , Ahn Jin‐Seok , Kim Jinkook , Shim Young Mog , Kim Jung Han , Park Keunchil , Han Joungho , Ahn Myung‐Ju 
Published: January 2010

AbstractBACKGROUND:The signal transducer and activator of transcription 3 (STAT3) play a key role in the downstream pathway of the epidermal growth factor receptor (EGFR) in nonsmall cell lung cancer and promote cell proliferation, invasion, and angiogenesis. The clinical significance of phosphorylated STAT3 (pSTAT3), EGFR, p53, and vascular endothelial growth factor receptor 1 (VEGFR‐1) expression in patients with completely resected lung adenocarcinoma was evaluated to determine the effects of pSTAT3 in tumor angiogenesis and proliferation.METHODS:The expressions of pSTAT3, EGFR, p53, and VEGFR‐1 were evaluated by immunohistochemical staining of tissue microarrays from 162 samples of resected lung adenocarcinoma.RESULTS:The median age of the 162 patients was 62 years, the median disease‐free survival was 41.7 months, and the median OS (OS) was 80.2 months. Expression of pSTAT3, EGFR, p53, and VEGFR‐1 was detected in 51.2%, 71%, 35.2%, and 35.2% of the samples, respectively. pSTAT3 expression was correlated significantly with VEGFR‐1 expression (P = .025). The coexpression of pSTAT3 and VEGFR‐1 was correlated with increased lymph node involvement (P = .021) and a trend toward a short OS (P = .085). In multivariate analysis, the expression levels of p53 and VEGFR‐1 were identified as independent prognostic factors that affected OS.CONCLUSIONS:The results of this study suggested that pSTAT3 and VEGFR‐1 expression may play roles in the tumor progression and angiogenesis of lung adenocarcinoma. Further studies are needed, however, to uncover the detailed mechanisms that underlie the roles of these proteins in lung adenocarcinoma. Cancer 2010. © 2010 American Cancer Society.