bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of microextrusion and addition of graphite nanoplatelets on bulk and surface mechanical properties of UHMWPE
Authors: Delgado‐Rangel Jose‐Alejandro , Addiego Frédéric , Eddoumy Fatima , Ahzi Saïd , Patlazhan Stanislav , Toniazzo Valérie , Ruch David 
Published: February 2012

AbstractA new processing route for producing ultra‐high molecular weight polyethylene (UHMWPE) nanocomposite combining swelling in toluene, microextrusion, and compression‐molding was developed. Using this novel method, extruded neat UHMWPE (e‐PE), and extruded UHMWPE blended with 0.5 wt % of graphite nanoplatelets (e‐PE/g) were processed. UHMWPE was also processed by compression‐molding (PE) as reference material. Bulk mechanical behavior of the materials was evaluated by tensile, bending and impact tests, while surface mechanical behavior was assessed by scratch and sliding wear experiments. We found that e‐PE/g has a brittle tensile behavior in comparison with the two other grades. Bending and impact toughness increase in this order: PE ≈ e‐PE/g < e‐PE. Scratch behavior of the materials is quite similar, e‐PE has however the lowest friction coefficient, and hence, exhibits antifriction properties. The cumulative sliding energy increases in this order: e‐PE ≈ PE < e‐PE/g, indicating that e‐PE/g may have a lower wear resistance as compared to the two other materials. The combination of extrusion with compression‐molding caused the formation of well‐consolidated meso‐domains containing oriented chains. Such a new morphology is at the origin of the high tensile strength, high fracture toughness, and antifriction properties of e‐PE that appears like a promising material for medical or machine construction applications. The addition of graphite nanoplatelets induces a poor consolidation that resulted from the segregation of the fillers between powder grains of UHMWPE. This explains the brittle tensile behavior and the high cumulative sliding energy of the UHMWPE nanocomposite. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
The structure of novel polyurethanes containing synthetic poly[(R,S)‐3‐hydroxybutyrate]
Authors: Brzeska Joanna , Dacko Piotr , Gębarowska Katarzyna , Janik Helena , Kaczmarczyk Bożena , Kasperczyk Janusz , Kowalczuk Marek , Rutkowska Maria 
Published: February 2012

AbstractThe aim of this study was to estimate the structure of new polyurethanes with the potential to be used in medicine. Atactic poly[(R,S)‐3‐hydroxybutyrate], obtained via a ring‐opening polymerization, and polycaprolactonediol or polyoxytetramethylenediol were used to built the soft segments. 4,4′‐methylene dicyclohexyl diisocyanate and 1,4‐butanediol were the components to form hard segments. At FTIR spectra of obtained polyurethanes the bands attributed to NCO groups completely disappeared, similarly as these of OH groups and the new band characteristic for stretching vibrations of bonded urethane NH groups appeared. Polyurethanes with low‐molecular weight were obtained. The observation of FTIR and 1H‐NMR spectra had been suggested that NH groups form two types of hydrogen bonds: with CO urethane (possibly with ester group) and ether groups. An addition of poly[(R,S)‐3‐hydroxybutyrate] caused the slight increase in number of urethane–urethane hydrogen bonds. For some of polyurethanes (based on polyoxytetramethylenediol) the allophanate structures were obtained. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Cross‐Coupling of Aryllithiums with Aryl and Vinyl Halides in Flow Microreactors
Authors: Nagaki Aiichiro , Moriwaki Yuya , Haraki Suguru , Kenmoku Akira , Takabayashi Naofumi , Hayashi Atsushi , Yoshida Jun‐Ichi 
Published: February 2012

AbstractThe use of Pd catalysts that contained a carbene ligand, such as PEPPSI‐SIPr, speeded up the Murahashi coupling of ArLi with ArBr, by enabling its integration with the Br/Li exchange of ArBr with BuLi in flow. Space integration realized the rapid cross‐coupling of two different ArBr substrates. However, the cross‐coupling reaction with vinyl halides could not be achieved under similar conditions. Pd(OAc)2 was an effective catalyst, and the space integration of the Br/Li exchange of ArBr with BuLi and the Murahashi coupling with vinyl halides was successfully achieved.
Biotechnological production of succinic acid: current state and perspectives
Authors: Cheng Ke‐Ke , Zhao Xue‐Bing , Zeng Jing , Zhang Jian‐An 
Published: February 2012

AbstractSuccinic acid has multiple practical applications (e.g. synthesis of 1,4‐butanediol, tetrahydrofuran, gamma‐butyrolactone, and as a monomer of some biodegradable polymers). Bio‐based succinic acid is a potential substitute for current petrochemical production. Facing a shortage of crude oil supply and sharply rising oil prices, biological production of succinic acid from abundant and available biomass has become a topic of worldwide interest. Although great progress has been made in recent decades, much needs to be developed further in order to achieve economic viability. This paper reviews developments in technology and updates research progress of biosuccinate production, including pathways, micro‐organisms, culture conditions, as well as integrated production with other high‐value‐added products. Finally, strategies are proposed for successful commercialization of fermentative succinic acid production. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
Motivation as Mediator Between National Identity and Intention to Volunteer
Authors: Lai Mark H. C. , Ren Maggie Y. W. , Wu Anise M. S. , Hung Eva P. W. 
Published: February 2012

ABSTRACTAlthough there is a large volume of research on the relationship between social identity and volunteerism, little attention was given to national identity in volunteerism research. This study examined the role of national identity in motivating people to volunteer in the Chinese culture and its role in differentiating those who showed no interest in voluntary work (i.e. non‐volunteers) from those who wanted to volunteer but did not (i.e. potential volunteers). Two hundred ninety‐nine participants (age, M = 34.14 years) filled out a questionnaire on their demographics, experience of volunteering, intention to volunteer, volunteer motivations, and national identity. Results showed that a stronger national identity was associated with greater volunteer motivations. Mediation analyses further supported the positive indirect effect of national identity on intention to volunteer through strengthening volunteer motivations. Marital status was the only significant factor that differentiated current volunteers from potential volunteers. We concluded that citizens’ volunteer motivation increases with national identity, yet concrete measures to bring potential volunteers to actual volunteering need to be further explored. Copyright © 2012 John Wiley & Sons, Ltd.
Assessments and admissions during the first 6 years of a UK medium secure DSPD service
Authors: Freestone Mark , Taylor Celia , Milsom Sophia , Mikton Chris , Ullrich Simone , Phillips Ophelia , Coid Jeremy 
Published: February 2012

ABSTRACTBackgroundOffenders with personality disorder represent a considerable burden on mental health and criminal justice services. Millfields Unit was one of the pilot medium secure units (MSUs) established by the UK Department of Health and Ministry of Justice to provide dedicated services for such individuals.AimsOur study aimed to describe a complete cohort of referrals made to the service and to explore decisions on admissions to the Unit.MethodsFile review was used to collect a structured data set of information on the first 158 referrals. These were then analysed descriptively and inferentially.ResultsPrevious psychological treatment in prison and evidence of motivation for further treatment were the strongest predictors of admission to the service. People admitted showed evidence of more extensive criminal histories, prior treatment failure and higher level of risk than those accepted into conventional medium secure units. Despite the stated purpose of the units being for people with personality disorder, a high number of patients with a primary diagnosis of psychotic illness were referred.ConclusionThe new service accepted a high‐risk group of people with personality disorder whose needs would not otherwise have been met. Copyright © 2012 John Wiley & Sons, Ltd.
Amidetriazole: A Versatile Building Block for Construction of Oxyanion Anion Receptors
Authors: Li Yong‐Jun , Xu Liang , Yang Wen‐Long , Liu Hui‐Biao , Lai Siu‐Wai , Che Chi‐Ming , Li Yu‐Liang 
Published: February 2012

AbstractThe design and synthesis of efficient receptors for tetrahedral oxyanions is an emerging field in supramolecular chemistry. Herein, we have developed a urea‐like anion‐recognizing motif, amidetriazole, which can be easily synthesized and derived and shows good solubility. A series of simple acyclic receptors were designed and synthesized to confirm the potential of amidetriazole for the construction of tetrahedral oxyanion receptors. This molecular platform can be used extensively for the construction of numerous receptor systems appended with functional groups, which opens the way to many applications in the field of supramolecular chemistry.
Simulation of ultrasonic wave propagation in anisotropic poroelastic bone plate using hybrid spectral/finite element method
Authors: Nguyen Vu‐Hieu , Naili Salah 
Published: February 2012

SUMMARYThis paper deals with the modeling of guided waves propagation in in vivo cortical long bone, which is known to be anisotropic medium with functionally graded porosity. The bone is modeled as an anisotropic poroelastic material by using Biot's theory formulated in high frequency domain. A hybrid spectral/finite element formulation has been developed to find the time‐domain solution of ultrasonic waves propagating in a poroelastic plate immersed in two fluid halfspaces. The numerical technique is based on a combined Laplace–Fourier transform, which allows to obtain a reduced dimension problem in the frequency–wavenumber domain. In the spectral domain, as radiation conditions representing infinite fluid halfspaces may be exactly introduced, only the heterogeneous solid layer needs to be analyzed by using finite element method. Several numerical tests are presented showing very good performance of the proposed procedure. A preliminary study on the first arrived signal velocities computed by using equivalent elastic and poroelastic models will be presented.Copyright © 2012 John Wiley & Sons, Ltd.
A note on the null condition for quadratic nonlinear Klein‐Gordon systems in two space dimensions
Authors: Katayama Soichiro , Ozawa Tohru , Sunagawa Hideaki 
Published: March 2012

AbstractWe consider the Cauchy problem for quadratic nonlinear Klein‐Gordon systems in two space dimensions with masses satisfying the resonance relation. Under the null condition in the sense of J.‐M. Delort, D. Fang, and R. Xue (J. Funct. Anal. 211 (2004), no. 2, 288–323), we show the global existence of asymptotically free solutions if the initial data are sufficiently small in some weighted Sobolev space. Our proof is based on an algebraic characterization of nonlinearities satisfying the null condition. © 2012 Wiley Periodicals, Inc.
Broad near‐infrared fluorescence properties of Nd‐doped PbClF crystals
Authors: Wang Qingguo , Su Liangbi , Li Hongjun , Zheng Lihe , Xu Xiaodong , Wu Feng , Tang Huili , Jiang Dapeng , Chen Weichao , Xu Jun 
Published: March 2012

AbstractNd‐doped PbClF crystals were grown with modified Bridgman method. Broad and flat emission band at 1.0 μm was observed. The FWHM value of 0.0091 wt.% Nd3+‐doped PbClF crystal at 1064 nm reached up to 30 nm with the peak emission cross‐section of 1.05×10‐19 cm2. All the results indicated that Nd‐doped PbClF crystal should be a promising tunable and ultrafast laser material. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
(Benzimidazolin‐2‐ylidene)–AuI–Alkynyl Complexes: Syntheses, Structure, and Photophysical Properties
Authors: Garg Jai Anand , Blacque Olivier , Heier Jakob , Venkatesan Koushik 
Published: February 2012

AbstractA series of N‐heterocyclic carbene‐based AuI–σ‐acetylide complexes of the type [(Bimz)Au–C≡CR] (Bimz = benzimidazolin‐2‐ylidene; R = aryl, silyl groups) (1a–1l, 2, 3) were prepared from the precursor [(Bimz)AuICl] by an in situ deprotonation of the terminal alkynes. Steady‐state photoluminescence studies revealed that most of these complexes exhibit phosphorescence at room temperature and in 77 K rigidified matrices. Molecular structures were determined by single‐crystal X‐ray diffraction studies for complexes 1a, 1b, 1e, 1f, 1h, 1k, and 1l. Complexes 1f, 1h, and 1l revealed weak unsupported aurophilic interactions. Cyclic voltammetry studies exhibited irreversible behavior with one oxidation peak potential (Ep,a) for most cases in the region 0.7–1.4 V. Experimental and DFT studies suggest that the nature of the emission is predominantly of intraligand character 3IL(π–π*) with a slight perturbation from the metal.
Structural Conformation and Optical and Electrochemical Properties of Imidazolyl‐Substituted Naphthalenediimide and Its HgII, CdII, and CuII Halide Complexes (Eur. J. Inorg. Chem. 8/2012)
Authors: Jiang Jia‐Jian , Yan Cheng , Pan Mei , Wang Zi , Deng Hai‐Ying , He Jian‐Rong , Yang Qing‐Yuan , Fu Lei , Xu Xian‐Fang , Su Cheng‐Yong 
Published: March 2012

AbstractThe cover picture shows that an “end‐core‐end”‐type NDI‐based ligand could take either trans, L or cis conformations, just like the two pincers of a crab can have different relative positions. Its coordination with HgII, CdII, CuII halides leads to the formation of M2L2 metallocycles, 1D zigzag chains or ML metallocycle structures. Details are discussed in the article by M. Pan, C.‐Y. Su et al. on p. 1171 ff. magnified image
α‐Pyrones and Pyranes from the Plant Pathogenic Fungus Pestalotiopsis scirpina
Authors: Li Jian , Wu Xianfu , Ding Gang , Feng Yu , Jiang Xuejun , Guo Liangdong , Che Yongsheng 
Published: March 2012

AbstractThree new α‐pyrones, scirpyrones A–C (1–3), and four new pyranes, scirpyranes A–D (4–7), were isolated from solid cultures of the plant pathogen Pestalotiopsis scirpina. Their structures were elucidated primarily by NMR experiments. The absolute configurations of C‐7 and C‐2′ in 1, C‐7 in 2, and C‐6 and C‐7 in 3 were deduced on the basis of circular dichroism (CD) data, whereas those of the secondary alcohols in 4–7 were determined by a modification of Mosher's method. Compound 1 is the first described 6‐(5‐oxotetrahydrofuran‐2‐yl)‐2H‐pyran‐2‐one. Compounds 4–6 showed significant cytotoxicity towards MCF‐7 cells.
Time‐resolved measurements of pyrolysis and combustion products of PMMA
Authors: Ghosh Ruby N. , Wichman Indrek S. , Kramer Cory A. , Loloee Reza 
Published: February 2012

ABSTRACTWe studied transient chemical speciation during high‐temperature solid material pyrolysis and combustion in air. Our objective was to develop a database of chemical burn signatures. The material tested was the thermoplastic PMMA. Material samples were heated in an infrared furnace until they pyrolyzed, ignited, and combusted in air. Time‐resolved quantitative measurements of the exhaust species CO2, O2, hydrocarbons, and CO along with exhaust gas temperature were obtained. Two categories of experiments were conducted: (1) pyrolysis tests in which there was no combustion; (2) combustion tests with chemical reaction and heat release.During heating, the sample underwent numerous processes that appear as diagnostic sequences. In the pyrolysis tests, as the furnace temperature was raised, the CO and hydrocarbon (HC) signals underwent transition from one peak to two peaks. In the combustion tests, spontaneous ignition occurred at higher test temperatures as evidenced by an exothermic reaction reported by the thermocouples, leading to three‐peak CO and HC profiles. The measured O2/CO2 ratio of 1.3 ± 0.1 agreed with stoichiometric methyl‐methacrylate monomer decomposition.Calculations of the power output using two independent methods supported (1) that combustion was experimentally observed in the furnace, and (2) the accuracy of the combustion gas analysis. Copyright © 2012 John Wiley & Sons, Ltd.
Operating Temperature Dependency on Performance Degradation of Direct Methanol Fuel Cells
Authors: Park J.‐Y. , Kim J.‐H. , Seo Y. , Yu D.‐J. , Cho H. , Bae S. J. 
Published: February 2012

AbstractThe effect of operating temperature on performance degradation of direct methanol fuel cell (DMFCs) is examined to disclose the main parameter of the degradation mechanism and the degradation pattern in the membrane electrode assemblies (MEAs). The DMFC MEA degradation phenomenon is explained through the use of various electrochemical/physicochemical tools, such as electrochemical impedance spectroscopy, electrode polarization, methanol stripping voltametry, field emission‐scanning electron microscopy, X‐ray diffraction, inductively coupled plasma‐atomic emission spectroscopy, and X‐ray photoelectron spectroscopy analysis. The operation of DMFC under high temperature accelerates the degradation process of the DMFC. The higher degradation rate under high temperature DMFC operation is mainly attributed to the formation of membrane pinhole with interfacial delamination and cathode degradation. A high operating temperature may result in more considerable thermal and mechanical stress of the polymeric membrane continuously due to frequent dry–wet cycling mode and substantial uneven distribution of water between the anode and the cathode during a long period of DMFC operation. On the other hand, the electrochemical surface area deterioration by Pt coarsening and ionomers loss is not directly related to the larger DMFC performance decay at high temperature.
The association of psychotropic medication use with the cognitive, functional, and neuropsychiatric trajectory of Alzheimer's disease
Authors: Rosenberg P. B. , Mielke M. M. , Han D. , Leoutsakos J. S. , Lyketsos C. G. , Rabins P. V. , Zandi P. P. , Breitner J. C. S. , Norton M. C. , Welsh‐Bohmer K. A. , Zuckerman I. H. , Rattinger G. B. , Green R. C. , Corcoran C. , Tschanz J. T. 
Published: February 2012

ObjectiveThe use of psychotropic medications in Alzheimer's disease (AD) has been associated with both deleterious and potentially beneficial outcomes. We examined the longitudinal association of psychotropic medication use with cognitive, functional, and neuropsychiatric symptom (NPS) trajectories among community‐ascertained incident AD cases from the Cache County Dementia Progression Study.MethodsA total of 230 participants were followed for a mean of 3.7 years. Persistency index (PI) was calculated for all antidepressants, selective serotonin reuptake inhibitors (SSRIs), antipsychotics (atypical and typical), and benzodiazepines as the proportion of observed time of medication exposure. Mixed‐effects models were used to examine the association between PI for each medication class and Mini‐Mental State Exam (MMSE), Clinical Dementia Rating Sum of Boxes (CDR‐Sum), and Neuropsychiatric Inventory – Total (NPI‐Total) trajectories, controlling for appropriate demographic and clinical covariates.ResultsAt baseline, psychotropic medication use was associated with greater severity of dementia and poorer medical status. Higher PI for all medication classes was associated with a more rapid decline in MMSE. For antidepressant, SSRI, benzodiazepine, and typical antipsychotic use, a higher PI was associated with a more rapid increase in CDR‐Sum. For SSRIs, antipsychotics, and typical antipsychotics, a higher PI was associated with more rapid increase in NPI‐Total.ConclusionsPsychotropic medication use was associated with more rapid cognitive and functional decline in AD, and not with improved NPS. Clinicians may tend to prescribe psychotropic medications to AD patients at risk of poorer outcomes, but one cannot rule out the possibility of poorer outcomes being caused by psychotropic medications. Copyright © 2012 John Wiley & Sons, Ltd.
Writing affects the brain network of reading in Chinese: A functional magnetic resonance imaging study
Authors: Cao Fan , Vu Marianne , Lung Chan Derek Ho , Lawrence Jason M. , Harris Lindsay N. , Guan Qun , Xu Yi , Perfetti Charles A. 
Published: February 2012

AbstractWe examined the hypothesis that learning to write Chinese characters influences the brain's reading network for characters. Students from a college Chinese class learned 30 characters in a character‐writing condition and 30 characters in a pinyin‐writing condition. After learning, functional magnetic resonance imaging collected during passive viewing showed different networks for reading Chinese characters and English words, suggesting accommodation to the demands of the new writing system through short‐term learning. Beyond these expected differences, we found specific effects of character writing in greater activation (relative to pinyin writing) in bilateral superior parietal lobules and bilateral lingual gyri in both a lexical decision and an implicit writing task. These findings suggest that character writing establishes a higher quality representation of the visual–spatial structure of the character and its orthography. We found a greater involvement of bilateral sensori‐motor cortex (SMC) for character‐writing trained characters than pinyin‐writing trained characters in the lexical decision task, suggesting that learning by doing invokes greater interaction with sensori‐motor information during character recognition. Furthermore, we found a correlation of recognition accuracy with activation in right superior parietal lobule, right lingual gyrus, and left SMC, suggesting that these areas support the facilitative effect character writing has on reading. Finally, consistent with previous behavioral studies, we found character‐writing training facilitates connections with semantics by producing greater activation in bilateral middle temporal gyri, whereas pinyin‐writing training facilitates connections with phonology by producing greater activation in right inferior frontal gyrus. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.
Calpain4 is required for activation of HER2 in breast cancer cells exposed to trastuzumab and its suppression decreases survival and enhances response
Authors: Kulkarni Sucheta , Saju Leya , Farver Carol , Tubbs Raymond 
Published: February 2012

AbstractOveractivation of HER2 and crosstalk of other HER family members contribute to a survival pathway of breast cancer cells exposed to trastuzumab, the therapeutic inhibitor of HER2 and thus, decrease response and promote resistance. We have explored the involvement of the intracellular cysteine protease calpain4, the common partner of isoforms calpain1 and calpain2, in the regulation of cell survival and trastuzumab‐response. Increase of calpain4 expression and isoform activities were detected in breast cancer cells and HER2‐positive tumors. Molecular analyses of parent and resistant cells suggested that perturbation of regulations, induced by calpain4 and of activities of HER2 and HER3, was associated with trastuzumab‐resistance. The suppression of calpain4 destabilized calpain1 and calpain2, however, did not prevent the activation of HER2 and HER3 or cell proliferation in the absence of trastuzumab. To understand the significance, the survival of parent and trastuzumab‐resistant cells in which calpain4 was suppressed, was assessed in the presence of trastuzumab; survival in each cell type was decreased and associated with a loss of HER2 and HER3 activity. Taken together, by contributing to the activation and the crosstalk of HER2, calpain4 promotes the survival pathway of breast cancer cells, and therefore, its suppression enhances trastuzumab‐response and decreases resistance.