bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quasi optimal finite difference method for Helmholtz problem on unstructured grids
Authors: Fernandes Daniel T. , Loula Abimael F. D. 
Published: December 2009

AbstractA quasi optimal finite difference method (QOFD) is proposed for the Helmholtz problem. The stencils' coefficients are obtained numerically by minimizing a least‐squares functional of the local truncation error for plane wave solutions in any direction. In one dimension this approach leads to a nodally exact scheme, with no truncation error, for uniform or non‐uniform meshes. In two dimensions, when applied to a uniform cartesian grid, a 9‐point sixth‐order scheme is derived with the same truncation error of the quasi‐stabilized finite element method (QSFEM) introduced by Babuška et al. (Comp. Meth. Appl. Mech. Eng. 1995; 128:325–359). Similarly, a 27‐point sixth‐order stencil is derived in three dimensions. The QOFD formulation, proposed here, is naturally applied on uniform, non‐uniform and unstructured meshes in any dimension. Numerical results are presented showing optimal rates of convergence and reduced
pollution effects for large values of the wave number. Copyright © 2009 John Wiley & Sons, Ltd.
Taylor series multipole boundary element‐mathematical programming method for 3D multi‐bodies elastic contact problems
Authors: Chen Zejun , Xiao Hong , Yang Xia , Su Chunjian 
Published: December 2009

AbstractUtilizing the mathematical programming technique of contact problems and Fast Multipole Boundary Element Method (FM‐BEM) theory, Taylor Series Multipole BEM (TSMBEM) for solving 3D multi‐bodies elastic frictional contact problems is presented based on the ‘node‐to‐surface’ contact model. The numerical method is able to analyze the large‐scale contact problems using non‐conforming or conforming boundary meshes. For multi‐bodies contact problems, the computational costs of contact identification can be effectively reduced by the contact table. The mathematical programming method for TSMBEM is presented based on the interpolation approach of contact elements. The linear system arising from multipole BEM is solved by using Generalized Minimal RESidual algorithm GMRES(m) in conjunction with near‐field preconditioning technique. The numerical experiments of flat punch and HC roll system are carried out by the newly developed multipole BEM. The numerical results are compared with the Hertz theoretical solutions, which illustrate the effectiveness and the validity of the numerical method for 3D multi‐bodies elastic frictional contact analysis. Copyright © 2009 John Wiley & Sons, Ltd.
The XFEM for high‐gradient solutions in convection‐dominated problems
Authors: Abbas Safdar , Alizada Alaskar , Fries Thomas‐Peter 
Published: December 2009

AbstractConvection‐dominated problems typically involve solutions with high gradients near the domain boundaries (boundary layers) or inside the domain (shocks). The approximation of such solutions by means of the standard finite element method requires stabilization in order to avoid spurious oscillations. However, accurate results may still require a mesh refinement near the high gradients. Herein, we investigate the extended finite element method (XFEM) with a new enrichment scheme that enables highly accurate results without stabilization or mesh refinement. A set of regularized Heaviside functions is used for the enrichment in the vicinity of the high gradients. Different linear and non‐linear problems in one and two dimensions are considered and show the ability of the proposed enrichment to capture arbitrary high gradients in the solutions. Copyright © 2009 John Wiley & Sons, Ltd.
A computer case definition for sudden cardiac death
Authors: Chung Cecilia P. , Murray Katherine T. , Stein C. Michael , Hall Kathi , Ray Wayne A. 
Published: December 2009

AbstractPurposeTo facilitate studies of medications and sudden cardiac death, we developed and validated a computer case definition for these deaths. The study of community dwelling Tennessee Medicaid enrollees 30–74 years of age utilized a linked database with Medicaid inpatient/outpatient files, state death certificate files, and a state ‘all‐payers’ hospital discharge file.MethodsThe computerized case definition was developed from a retrospective cohort study of sudden cardiac deaths occurring between 1990 and 1993. Medical records for 926 potential cases had been adjudicated for this study to determine if they met the clinical definition for sudden cardiac death occurring in the community and were likely to be due to ventricular tachyarrhythmias. The computerized case definition included deaths with (1) no evidence of a terminal hospital admission/nursing home stay in any of the data sources; (2) an underlying cause of death code consistent with sudden cardiac death; and (3) no terminal procedures inconsistent with unresuscitated cardiac arrest. This definition was validated in an independent sample of 174 adjudicated deaths occurring between 1994 and 2005.ResultsThe positive predictive value of the computer case definition was 86.0% in the development sample and 86.8% in the validation sample. The positive predictive value did not vary materially for deaths coded according to the ICO‐9 (1994–1998, positive predictive value = 85.1%) or ICD‐10 (1999–2005, 87.4%) systems.ConclusionA computerized Medicaid database, linked with death certificate files and a state hospital discharge database, can be used for a computer case definition of sudden cardiac death. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and characterization of physical crosslinking systems based on cyclodextrin inclusion/host‐guest complexation
Authors: Kaya Ethem , Mathias Lon J. 
Published: December 2009

AbstractNew supramolecular assemblies based on cyclodextrin and adamantane were prepared. Two methacrylate monomers bearing cyclodextrin and adamantane were synthesized, and copolymerized with poly(ethylene glycol) methyl ether methacrylate, (PEGMA, 300 g/mol), by free radical polymerization. Copolymers bearing pendent cyclodextrin and adamantane were characterized by NMR, FTIR, TGA, SEC, Differential scanning calorimetry (DSC), and UV‐visible spectrophotometer. All copolymers showed two distinct glass transitions. The specific interaction between pendent adamantyl and cyclodextrin was examined by 1H‐NMR. The viscoelastic properties of supramolecular assemblies were investigated with frequency and temperature sweep experiments. The specific host‐guest interaction between pendent adamantyl and cyclodextrin lead to large increases of the viscosity; and depending on the concentration of these groups, also to gel formation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 581–592, 2010
Poly(3‐hexylthiophene)‐b‐poly(3‐cyclohexylthiophene): Synthesis, microphase separation, thin film transistors, and photovoltaic applications
Authors: Wu Pei‐Tzu , Ren Guoqiang , Kim Felix S. , Li Chaoxu , Mezzenga Raffaele , Jenekhe Samson A. 
Published: December 2009

AbstractWe report the synthesis, characterization, microphase separation, field‐effect charge transport, and photovoltaic properties of regioregular poly(3‐hexylthiophene)‐b‐poly(3‐cyclohexylthiophene) (P3HT‐b‐P3cHT). Two compositions of P3HT‐b‐P3cHT (HcH63 and HcH77) were synthesized with weight‐average molecular weights of 155,500 and 210,800 and polydispersity indices of 1.45 and 1.57, respectively. Solvent‐casted HcH77 was found to self‐assemble into nanowires with a width of 12.5 ± 0.9 nm and aspect ratios of 50–120, as observed by TEM imaging. HcH77 and HcH63 annealed 280 °C were observed by small angle X‐ray scattering (SAXS) and wide angle X‐ray scattering (WAXS) to be microphase‐separated with characteristic length scales of 17.0–21.7 nm. The microphase‐separated domains were shown to be crystalline with interlayer backbone (100) d‐spacings of 1.69 and 1.40 nm, which correspond to the P3HT and P3cHT blocks, respectively. Field‐effect transistors fabricated from P3HT‐b‐P3cHT thin films showed a mobility of holes (0.0019 cm2/Vs) which is independent of thermal annealing. Bulk heterojunction solar cells based on HcH77/fullerene (PC71BM) blend thin films had a maximum power conversion efficiency of 2.45% under 100 mW/cm2 AM1.5 solar illumination in air. These results demonstrate that all‐conjugated block copolymers are suitable semiconductors for applications in field‐effect transistors and bulk heterojunction solar cells. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 614–626, 2010
Thermoresponsive fluorescent water‐soluble copolymers containing BODIPY dye: Inhibition of H‐aggregation of the BODIPY units in their copolymers by LCST
Authors: Nagai Atsushi , Kokado Kenta , Miyake Junpei , Cyujo Yoshiki 
Published: December 2009

AbstractNovel water‐soluble copolymers containing 4‐difluoro‐4‐bora‐3a,4a‐diaza‐s‐indacene (BODIPY) dyes were synthesized by reversible addition‐fragmentation chain transfer (RAFT) polymerization. The copolymers with both number‐average molecular weight between 5.0 × 103 and 5.8 × 103 and narrow molecular weight distribution (Mw/Mn < 1.19) were obtained by the copolymerization of (2‐dimethylamino)ethyl methacrylate (DMAEMA) and BODIPY‐based methyl methacrylate (1) with 2,2′‐azobis(isobutyronitrile) (AIBN) as an initiator in the presence of cumyl dithiobenzoate (CDB) as a chain transfer agent (CTA). The structures of the resulting copolymers were characterized by 1H, 13C, and 11B NMR spectroscopies, and the comonomer compositions were good consistent with the feed ratio. Characteristic optical properties of the obtained copolymers were investigated by UV‐vis and PL spectroscopic methods. The copolymers composed of [DMAEMA]: [1] = 98.0:2.0 and 99.4:1.4 led to thermoresponsive polymers having phase separation temperatures at 32 °C and 40 °C, respectively, depending on the compositions of hydrophilic/hydrophobic balances. Further, the effective reversible decrease/increase of the emission intensity of the copolymers led to the reversible formation/inhibition of the H‐aggregation between two BODIPY planes in the copolymers on heating and cooling across the border of LCST. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 627–634, 2010
Thermoresponsive PPEGMEA‐g‐PPEGEEMA well‐defined double hydrophilic graft copolymer synthesized by successive SET‐LRP and ATRP
Authors: Zhai Sujuan , Wang Beidi , Feng Chun , Li Yongjun , Yang Dong , Hu Jianhua , Lu Guolin , Huang Xiaoyu 
Published: December 2009

AbstractA series of well‐defined double hydrophilic graft copolymers containing poly[poly(ethylene glycol) methyl ether acrylate] (PPEGMEA) backbone and poly[poly(ethylene glycol) ethyl ether methacrylate] (PPEGEEMA) side chains were synthesized by the combination of single electron transfer‐living radical polymerization (SET‐LRP) and atom transfer radical polymerization (ATRP). The backbone was first prepared by SET‐LRP of poly(ethylene glycol) methyl ether acrylate macromonomer using CuBr/tris(2‐(dimethylamino)ethyl)amine as catalytic system. The obtained comb copolymer was treated with lithium diisopropylamide and 2‐bromoisobutyryl bromide to give PPEGMEA‐Br macroinitiator. Finally, PPEGMEA‐g‐PPEGEEMA graft copolymers were synthesized by ATRP of poly(ethylene glycol) ethyl ether methacrylate macromonomer using PPEGMEA‐Br macroinitiator via the grafting‐from route. The molecular weights of both the backbone and the side chains were controllable and the molecular weight distributions kept narrow (Mw/Mn ≤ 1.20). This kind of double hydrophilic copolymer was found to be stimuli‐responsive to both temperature and ion (0.3 M Cl− and SO). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 647–655, 2010
Synthesis and thermoreversible gelation of dendron‐like polypeptide/linear poly(ε‐caprolactone)/dendron‐like polypeptide triblock copolymers
Authors: You Yuan , Chen Yi , Hua Chong , Dong Chang‐Ming 
Published: December 2009

AbstractDendron‐like poly(γ‐benzyl‐L‐glutamate)/linear poly(ε‐caprolactone)/dendron‐like poly(γ‐benzyl‐L‐glutamate) triblock copolymers having 2m + 1 PBLG branches (denoted as PBLG‐Dm‐PCL‐Dm‐PBLG, m = 0, 1, 2, and 3) were for the first time synthesized by utilizing ring‐opening polymerization (ROP) and click chemistry. The bifunctional azide‐terminated PCL (N3‐PCL‐N3) was click conjugated with propargyl focal point PAMAM‐typed dendrons Dm to generate Dm‐PCL‐Dm, which was then used as macroinitiator for the ROP of BLG‐NCA monomer to produce the targeted PBLG‐Dm‐PCL‐Dm‐PBLG triblock copolymers. Their molecular structures and physical properties were characterized in detail by FTIR, NMR, gel permeation chromatography, differential scanning calorimetry, and wide angle X‐ray diffraction (WAXD). The crystallinity of the central PCL segment within these copolymers is increasingly suppressed by the flanking PBLG wedges, whereas the PBLG segments gradually changed from a β‐sheet conformation to an α‐helix conformation with the increasing PBLG branches. These triblock copolymers formed thermoreversible organogels in toluene, and the dendritic topology of PBLG wedges controlled their critical gelation concentrations. The self‐assembled structure of organogels was further characterized by means of transmission electron microscopy, WAXD, and small‐angle X‐ray scattering. The fibers with flat ribbon morphology were clearly shown, and the gelation occurred through a self‐assembled nanoribbon mechanism. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 709–718, 2010
Specific lectin interactions and temperature‐induced reversible gels in novel water‐soluble glycopolymers bearing maltotrionolactone pendant groups
Authors: Cerrada M. L. , Sánchez‐chaves M. , Ruiz C. , Fernández‐García M. 
Published: December 2009

AbstractGlycopolymers based on the incorporation of a diaminobutylmaltotrionolactone onto activated ethylene‐vinyl alcohol, EVOH, copolymers with distinct composition in the former counit have been prepared. Previous transformation of initial hydroxyl EVOH groups to other more reactive functional groups has been required. The activation has been performed in this current investigation by functionalization with either 4‐nitrophenyl carbonate or o‐phthalic acid groups. The structure of the resulting novel water‐soluble glycopolymers has been confirmed by FTIR, 1H and 13C‐NMR spectroscopies. In addition, the glass transition temperatures and thermal stability as well as the viscoelastic behavior in bulk and in water solution have been examined as a function of chemical linkage nature. The rheological evaluation confirms the reversible gel formation in all the cases. Finally, their affinity to Concanavalin A lectin has been also analyzed proving the feasible use of these glycopolymers as molecular recognition materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 719–729, 2010
Direct Lightning Hits on Wind Turbines in Winter Season Lightning Observation Results for Wind Turbines at Nikaho Wind Park in Winter
Authors: Asakawa A. , Shindo T. , Yokoyama S. , Hyodo H. 
Published: December 2009

AbstractLightning observation has been carried out at the Nikaho wind park since 2003 by CRIEPI and J‐Power using still cameras and specially designed Rogowski coils of wide frequency band from 0.1 Hz to 100 kHz. In 2005, 125 lightning flashes on wind turbines were observed and 85 lightning current records on wind turbines were obtained. The 50% value of lightning current peak is about 3.1 kA and the 50% value of charge amount of pulse‐type current and continuing‐type current are 0.13 C (18 data) and 33.8 C (67 data), respectively. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
X‐ray fluorescence portable systems for the rapid assessment of photographic techniques in notable art collections: the Alfred Stieglitz Collection
Authors: Grieten E. , Casadio F. 
Published: December 2009

AbstractIn the late nineteenth and early twentieth century photographers experimented, adapted and combined different techniques, using a wide array of chemicals leading to a vast range of commercial and self‐made photographs. Museum professionals, experts and collectors typically rely on visual and microscopic examination to identify photographic processes, however, visual identification alone can be misleading. The present study describes applications of portable and handheld X‐ray fluorescence(XRF) spectrometers to determine the metallic elements in photographic images, with special focus on one of the highest‐profile photographic collections in the world, that of Alfred Stieglitz. A protocol was developed for two types of XRF spectrometers, a portable micro‐focus system and a handheld macro‐set‐up, and validated with standard replicas of known photographic techniques. Qualitative XRF identification of the metallic salts allows unambiguous identification of the process used for each photograph. The portability of the systems makes the method applicable to the study of large collections in any location. In total, more than 60 photographs from the Alfred Stieglitz Collection were analyzed, leading to the revision of approximately 16% of the previous process identifications. These results are presented here for the first time. The correct identification of these photographs has significant impact on aspects of preventive conservation, exhibition and scholarly research, not only for the Art Institute of Chicago but also for other institutions and private collectors who own photographs from the Alfred Stieglitz Collection. Copyright © 2009 John Wiley & Sons, Ltd.
Epidemiology of mixed urinary incontinence in China
Authors: Zhu Lan , Li Lin , Lang Jinghe , Xu Tao , Wong Felix 
Published: December 2009

AbstractObjectivesTo determine the prevalence and risk factors for mixed urinary incontinence (MUI) among Chinese women.MethodIn this cross‐sectional survey study we analyzed the answers to a modified Bristol Female Lower Urinary Tract Symptoms questionnaire provided by 19 024 women older than 20 years and from 6 regions in China.ResultsThe overall prevalence of MUI was 9.4%. The prevalence of MUI increased with age and reached 24.1% among women older than 70 years. Multivariable logistic regression analysis revealed that age, vaginal delivery, chronic constipation, pelvic organ prolapse, chronic pelvic pain, respiratory system disease, menstrual disorder, urinary system disease, alcohol consumption, pelvic surgery, obesity, and a low educational level were independent risk factors for MUI.ConclusionWe found age, vaginal delivery, and chronic constipation to be the main risk factors for MUI among adult women in China.
Abiotic versus biotic hierarchies in the assembly of parasite populations
Authors: ANDERSON T. K. , SUKHDEO M. V. K. 
Published: December 2009

SUMMARYThe presence or absence of parasites within host populations is the result of a complex of factors, both biotic and abiotic. This study uses a non-parametric classification tree approach to evaluate the relative importance of key abiotic and biotic drivers controlling the presence/absence of parasites with complex life cycles in a sentinel, the common killifishFundulus heteroclitus. Parasite communities were classified from 480 individuals representing 15 fish from 4 distinct marsh sites in each of 4 consecutive seasons between 2006 and 2007. Abiotic parameters were recorded at continuous water monitoring stations located at each of the 4 sites. Classification trees identified the presence of benthic invertebrate species (Gammarussp. andLittorinasp.) as the most important variables in determining parasite presence: secondary splitters were dominated by abiotic variables including conductance, pH and temperature. Seventy percent of hosts were successfully classified into the correct category (infected/uninfected) based on only these criteria. The presence of competent definitive hosts was not considered to be an important explanatory variable. These data suggest that the most important determinant of the presence of these parasite populations in the common killifish is the availability of diverse communities of benthic invertebrates.
How similar are adult second language learners and Spanish heritage speakers? Spanish clitics and word order
Authors: MONTRUL SILVINA 
Published: December 2009

ABSTRACTRecent studies of heritage speakers, many of whom possess incomplete knowledge of their family language, suggest that these speakers may be linguistically superior to second language (L2) learners only in phonology but not in morphosyntax. This study reexamines this claim by focusing on knowledge of clitic pronouns and word order in 24 L2 learners and 24 Spanish heritage speakers. Results of an oral production task, a written grammaticality judgment task, and a speeded comprehension task showed that, overall, heritage speakers seem to possess more nativelike knowledge of Spanish than their L2 counterparts. Implications for theories that stress the role of age and experience in L2 ultimate attainment and for the field of heritage language acquisition and teaching are discussed.
When speech is ambiguous, gesture steps in: Sensitivity to discourse-pragmatic principles in early childhood
Authors: SO WING CHEE , DEMIR ÖZLEM ECE , GOLDIN-MEADOW SUSAN 
Published: December 2009

ABSTRACTYoung children produce gestures to disambiguate arguments. This study explores whether the gestures they produce are constrained by discourse-pragmatic principles: person and information status. We ask whether children use gesture more often to indicate the referents that have to be specified (i.e., third person and new referents) than the referents that do not have to be specified (i.e., first or second person and given referents). Chinese- and English-speaking children were videotaped while interacting spontaneously with adults, and their speech and gestures were coded for referential expressions. We found that both groups of children tended to use nouns when indicating third person and new referents but pronouns or null arguments when indicating first or second person and given referents. They also produced gestures more often when indicating third person and new referents, particularly when those referents were ambiguously conveyed by less explicit referring expressions (pronouns, null arguments). Thus Chinese- and English-speaking children show sensitivity to discourse-pragmatic principles not only in speech but also in gesture.
Actualizable Potential, Reproduction, and Embryo Research: Bringing Embryos into Existence for Different Purposes or Not at All
Authors: PERSSON INGMAR , SAVULESCU JULIAN 
Published: December 2009

In several papers, John Harris has argued that ifi)it is morally permissible to engage in reproduction, whether natural or artificial, despite knowledge that a large number of embryos will fail to implant and quickly die, thenii)it is morally permissible to produce embryos for other purposes that involve killing them, for instance, to harvest stem cells that may be used to save lives.
First Report of Soilborne wheat mosaic virus on Triticum aestivum in Washington State
Authors: Murray T. D. , Pappu H. R. , Smiley R. W. 
Published: December 2009

SBWMV was recently also reported from an adjacent county in Oregon. Confirmation of SBWMV in Washington highlights the need for increased awareness of the disease and implementing measures to contain its further spread in the region. Accepted for publication 18 September 2009. Published 4 December 2009.