bluuebunny/crossref_metadata_2025_split huggingface dataset:
Health care disparities and language use at home among latino, asian american, and american indian adolescents: Findings from the california health interview survey
Authors: Hahm Hyeouk Chris , Lahiff Maureen , Barreto Rose M. , Shin Sunny , Chen Wan‐Yi 
Published: December 2007

AbstractUsing the 2001 California Health Interview Survey, this study compared health status, medical insurance, and having a usual source of care for 2,230 ethnic minority adolescents based on language use at home: Group 1, English only; Group 2, both English and another language; and Group 3, exclusively another language. Adjusting for demographic variables, adolescents in Group 3 were more likely to report fair or poor health (OR=2.37, p=.012) and to not have medical insurance (OR=4.61, p<.001) compared to adolescents in Group 1. Young adolescents in Group 3 were more likely to have no usual source of care (OR=4.07, p=.029). Interventions need to consider language barriers in the context of an adolescent's age. © 2007 Wiley Periodicals, Inc.
Faith‐placed parenting intervention
Authors: Patrick Megan E. , Rhoades Brittany L. , Small Meg , Coatsworth J. Douglas 
Published: December 2007

AbstractCollaboration with religious institutions is recommended as a frontier for prevention science. Little is known about the effectiveness of programs currently disseminated by churches. This pilot program investigated potential advantages and disadvantages of university collaborations in faith settings, by implementing the Staying Connected with Your Teen parenting program (N=13 parents) in a single congregation. The mixed‐method assessment included surveys, a focus group, and observation to gather information about implementation. Meeting time, location, parallel youth programming, endorsement by trusted leaders, and use of existing social networks were indicated by past research and described by participants as potential advantages to an evidence‐based program implementation in faith communities. © 2007 Wiley Periodicals, inc.
Violence breeds violence: Childhood exposure and adolescent conduct problems
Authors: Weaver Chelsea M. , Borkowski John G. , Whitman Thomas L. 
Published: December 2007

AbstractThe relationships between childhood exposure to violence and adolescent conduct problems were investigated in a sample of 88 primiparous adolescent mothers and their children. Regression analyses revealed that witnessing violence and victimization prior to age 10 predicted delinquency and violent behaviors, even after controlling for prenatal maternal and early childhood externalizing problems. Social competency and depression during middle childhood moderated the relationship between victimization and violent behaviors for girls, but not boys: Lower levels of social competency and depression served as risk factors for delinquency among teenage girls who experienced victimization during childhood. These findings have important implications for youth violence prevention programs. © 2007 Wiley Periodicals, Inc.
Thickness‐two graphs part one: New nine‐critical graphs, permuted layer graphs, and Catlin's graphs
Authors: Boutin Debra L. , Gethner Ellen , Sulanke Thom 
Published: December 2007

AbstractThe purpose of this article is to offer new insight and tools toward the pursuit of the largest chromatic number in the class of thicknesstwo graphs. At present, the highest chromatic number known for a thickness‐two graph is 9, and there is only one known color‐critical such graph. We introduce 40 small 9‐critical thickness‐two graphs, and then use a newconstruction, the permuted layer graphs, together with a construction of Hajós to create an infinite family of 9‐critical thickness‐two graphs. Finally, a non‐trivial infinite subfamily of Catlin's graphs, with directly computable chromatic numbers, is shown to have thickness two. © 2007 Wiley Periodicals, Inc. J Graph Theory 57: 198–214, 2008
Infinite paths in planar graphs V, 3‐indivisible graphs
Authors: Yu Xingxing 
Published: December 2007

AbstractWe prove Nash‐Williams' conjecture that every 4‐connected, 3‐indivisible, infinite, planar graph contains a spanning 2‐way infinite path. A graph is said to be 3‐indivisible if the deletion of any finite set of vertices results in at most two infinite components. © 2007 Wiley Periodicals, Inc. J Graph Theory 57: 275–312, 2008
On the maximum number of cycles in a planar graph
Authors: Aldred R. E. L. , Thomassen Carsten 
Published: December 2007

AbstractLet G be a graph on p vertices with q edges and let r = q − p = 1. We show that G has at most ${15\over 16} 2^{r}$ cycles. We also show that if G is planar, then G has at most 2r − 1 = o(2r − 1) cycles. The planar result is best possible in the sense that any prism, that is, the Cartesian product of a cycle and a path with one edge, has more than 2r − 1 cycles. © Wiley Periodicals, Inc. J. Graph Theory 57: 255–264, 2008
Practice and endpoint accuracy with the left and right hands of old adults: The right‐hemisphere aging model
Authors: Poston Brach , Enoka Joel A. , Enoka Roger M. 
Published: December 2007

AbstractThe purpose of the study was to quantify the aging‐related differences in endpoint accuracy during isometric contractions of the left and right hands based on the prediction that declines in motor performance with aging may be greater for muscles controlled by the right hemisphere. Twelve young (6 men, 25 ± 5 years) and 12 old (6 men, 76 ± 6 years) adults performed a task that involved matching the peak of a force–time trajectory to a target. The old adults were less accurate than the young men and exhibited greater endpoint error with the left hand than the right hand on day 1, but not on days 2 and 3. Although electromyographic amplitude was similar between hands, old adults exhibited greater timing variability. These findings indicate that given sufficient practice there was no difference in endpoint accuracy between the left and right hands of old adults, which is not consistent with the prediction of an asymmetrical decline in motor performance by the right‐hemisphere aging model. Conversely, an inability by an old adult to achieve similar accuracy with both hands during such tasks likely indicates an underlying motor impairment. Muscle Nerve, 2007
Trialkoxysilane‐capped acrylic resin/alumina hybrid materials prepared by in situ sol–gel process
Authors: Li Mingqi , Zhou Shuxue , You Bo , Wu Limin 
Published: December 2007

AbstractThe (3‐methacryloxypropyl)trimethoxysilane (MPMS) capped acrylic resin/alumina hybrid materials with highly homogeneous structure were successfully prepared by in situ sol–gel process. The effects of the contents of alumina, ethylacetoacetate (EAA), and water as well as the types of catalyst on the structures and properties of the hybrid materials were studied. It was found that the Tg, thermal stability, microhardness, and Young's modulus of the hybrid materials were obviously improved with increasing alumina and water contents, low EAA content, and catalyst employed. POLYM. COMPOS., 2008. © 2007 Society of Plastics Engineers
Synthesis and characterization of organo‐attapulgite/polyaniline‐dodecylbenzenesulfonic acid based on emulsion polymerization method
Authors: Lei Xiping , Liu Yushan , Su Zhixing 
Published: December 2007

AbstractOrgano‐attapulgite (OAT) was obtained by pretreating attapulgite (AT) with hexadecyltrimethyl ammonium bromide (HDTMABr) and dodecylbenzenesulfonic acid doped polyaniline (PAn‐DBSA) (OAT/PAn‐DBSA) was synthesized by emulsion polymerization at different OAT weight ratios. The perhaps polymerization procedure was supposed. The chemical structure and electronic absorption of the composites was confirmed by FTIR and UV–Vis spectroscopy, respectively. According to the X‐ray diffraction (XRD) results, it can be concluded that HDTMABr and PAn‐DBSA was just adsorbed on the surface of AT during the cation‐exchange process and OAT respectively without destroying the crystalline structure of AT or OAT. The composites showed a higher thermal stability than pure PAn‐DBSA by introduction of OAT into this polymerization system by using TGA analysis. Morphologies of the samples were confirmed by TEM and it showed that OAT was dispersed well in organic solvent after AT was pretreated with HDTMABr. The morphologies of OAT/PAn‐DBSA also supported the perhaps formation procedure we hypothesized. The electrical conductivity of the composite decreased with increasing the feed weight ratios of OAT in this polymerization system. POLYM. COMPOS., 2008 © 2007 Society of Plastics Engineers
Impact modified polyamide‐6/organoclay nanocomposites: Processing and characterization
Authors: Isik Isil , Yilmazer Ulku , Bayram Goknur 
Published: December 2007

AbstractThe effects of melt state compounding of ethylene‐butyl acrylate‐maleic anhydride (E‐BA‐MAH) terpolymer and/or three types of organoclays (Cloisite® 15A, 25A, and 30B) on thermal and mechanical properties and morphology of polyamide‐6 are investigated. E‐BA‐MAH formed spherical domains in the materials to which it is added, and increased the impact strength, whereas the organoclays decreased the impact strength. In general, the organoclays increased the tensile strength (except for Cloisite 15A), Young's modulus and elongation at break, but the addition of E‐BA‐MAH had the opposite effect. XRD patterns showed that the interlayer spacing for the organoclays Cloisite 25A and Cloisite 30B increased in both polyamide‐6/organoclay binary nanocomposites and in polyamide‐6/organoclay/impact modifier ternary systems. TEM analysis showed that exfoliated‐intercalated nanocomposites were formed. The crystallinities of polyamide‐6/organoclay nanocomposites were in general lower than that of polyamide‐6 (except for Cloisite 15A). In ternary nanocomposites, crystallinities generally were lower than those of polyamide‐6/organoclay nanocomposites. Cloisite 15A containing ternary nanocomposites had higher tensile and impact strengths and Young's modulus than the ternary nanocomposites prepared with Cloisite 25A and Cloisite 30B, owing to its surface hydrophobicity and compatibility with the impact modifier. POLYM. COMPOS., 2008. © 2007 Society of Plastics Engineers
Polyester composites reinforced with noncrimp stitched glass fabrics: Experimental characterization of composites and investigation on the interaction between glass fiber and polyester matrix
Authors: Cecen Volkan , Sarikanat Mehmet , Seki Yoldas , Yildiz Hasan , Tavman Ismail H. 
Published: December 2007

AbstractThe primary purpose of the study was to investigate the anisotropic behavior of different noncrimp stitched fabric reinforced polyester composites. The effects of geometric variables on composite structural integrity and strength are illustrated. Hence, tensile, three‐point bending flexural and short beam shear tests were conducted up to failure on specimens strengthened with different layouts of fibrous plies in noncrimp stitched fabric. The remark, based on the observations while tensile testing, is that the stress–strain curves of polyester based composites were linear in the direction of fibers. However, in the matrix dominated orientations nonlinear relation between the stress and the strain was observed. Another aim of the present work was to investigate the interaction between glass fiber and polyester matrix. The experiments, in conjunction with scanning electron photomicrographs of fractured surfaces of composites, were interpreted in an attempt to explain the interaction between glass fiber and polyester and were interpreted in an attempt to explain the instability of polyester resin–glass fiber interfaces. It was concluded that the polymer was either deposited between adjacent fibers or as widely separated islands on the fiber surface. Infrared spectra of the cured polyester and its glass fiber composite were obtained by Fourier transform infrared spectroscopy. POLYM. COMPOS., 2008. © 2007 Society of Plastics Engineers
Processability studies of silica‐thermoset polymer matrix nanocomposites
Authors: Lekakou C. , Kontodimopoulos I. , Murugesh A.K. , Chen Y.L. , Jesson D.A. , Watts J.F. , Smith P.A. 
Published: December 2007

AbstractThe aim of this study is to investigate the processability of silica‐thermoset polymer matrix nanocomposites in terms of dispersion of silica nanoparticles and their effect on curing. Two thermosetting resins were considered, an epoxy and a polyester resin, with 5% silica, although 1% silica was also used in preliminary studies in the polyester system. Various combinations of mechanical mixing and sonication were investigated for the dispersion of silica nanoparticles under different processing conditions and times in solvent‐free and solvent‐containing systems. It was found that the best dispersion route involved a solvent‐aided dispersion technique. Consequently, different procedures for the solvent removal were investigated. Optical microscopy and SEM were used to characterize the resulting nanocomposites. DSC and rheological DMTA tests demonstrated that the silica nanoparticles shorten the gel time and promote curing in these thermosetting systems. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers
Elongational viscosity of LDPEs and polystyrenes using entrance loss data
Authors: Walczak K. , Gupta M. , Koppi K.A. , Dooley J. , Spalding M.A. 
Published: December 2007

AbstractFor two low‐density polyethylenes and two polystyrenes, axisymmetric and planar elongational viscosities are estimated using entrance loss data from capillary and slit rheometers, respectively. The elongational viscosity is estimated by optimizing the values of various parameters in the Sarkar–Gupta elongational viscosity model such that the entrance loss predicted by a finite element simulation agrees with the corresponding experimental data. The predicted entrance loss is in good agreement with the experimental data at high flow rates. The difference in the experimental and predicted entrance loss at lower flow rates might have been caused by large error in the experimental data in this range. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers
Structural characterization and mass transfer properties of dense segmented polyurethane membrane: Influence of hard segment and soft segment crystal melting temperature
Authors: Mondal S. , Hu J.L. 
Published: December 2007

AbstractAn attempt has been taken to investigate the microstructure and mass transfer properties of polycaprolactone diol (Mn = 2000 g mol–1, PCL 2000)‐based dense segmented polyurethane (SPU) membrane as a function of hard segment (HS) content. Structure of SPUs were investigated by Fourier transform infrared analysis, wide angle X‐ray diffraction, differential scanning calorimetry, dynamic mechanical thermal analysis, and scanning electron microscopy (SEM). On the other hand, mass transfer properties were measured by equilibrium sorption, dynamic sorption, and water vapor permeability measurements. From the experimental results, it was observed that with the increasing HS content in SPU the percentage crystallinity decreases, whereas the glassy state storage modulus increases. α transition temperature of polyurethane copolymers also increases with increasing HS content. SEM micrograph shows the dense surface structure of SPU films. Mass transfer rate of dense polyurethane membranes decreases with increasing HS content. In contrast, hydrophilic segment and soft segment crystal melting could enhance the mass transfer properties. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers
Interaction of thermoplastic polyurethane with polyamide 1212 and its influence on the thermal and mechanical properties of TPU/PA1212 blends
Authors: Li Wanli , Liu Jinli , Hao Chaowei , Jiang Kai , Xu Duanfu , Wang Dujin 
Published: December 2007

AbstractTo improve the heat resistance of polyester‐based thermoplastic polyurethane (TPU), in the present work, polyamide 1212 (PA1212) was chosen as a modifier and a series of TPU/PA1212 blends with different compositions were prepared using a twin screw extruder. The solubility parameters, characteristic of chemical structures, hydrogen‐bonding interaction, as well as interfacial tension of the single component and blends were taken into account to describe the good compatibility of TPU/PA1212 blends. The effect of PA1212 content on the rheological behaviors, morphology, mechanical, and thermal properties of TPU/PA1212 blends were systematically investigated with scanning electron microscope, tensile strength measurement, thermal gravimetry analysis, differential scanning calorimetry, and Vicat softening temperature (VST). The results showed that PA1212 formed submicron dispersion domains in the TPU matrix, indicating good compatibility between TPU and PA1212. A slight increase of the tensile strength was achieved as PA1212 content is relatively low. Because of the strong hydrogen‐bonding interaction between TPU and PA1212, the thermal stability of the blends is improved, and VST values rise up from about 80 (pure TPU) to 100°C, showing attractive potential application. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers
Macroscopic failure of multilayered viscoelastic polymers
Authors: Wu Chunhui , Mantell Susan C. , Davidson Jane H. 
Published: December 2007

AbstractThis study considers creep deformation (macroscopic failure) of laminated polymer materials. A closed form analytical model is developed to characterize creep in laminates loaded in the linear viscoelastic region. For nonlinear viscoelastic loading, a numerical solution is developed. The models are based on an application of laminated plate theory to materials with viscoelastic layers. Both approaches are able to predict laminate behavior with input of appropriate material properties for each layer. Experimental data are presented, which confirm the validity of the analytical model for laminates constructed from nylon66 and liquid crystalline polymer films. The validated macroscale failure models are capable of characterizing a variety of materials. A case study is included to demonstrate the influence of layer properties and orientation on overall laminate performance. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers
A study of nano‐mechanical and macro‐mechanical properties of ethylene vinyl acetate
Authors: Kim Jaehyun , Wang Janson , Kang Ho‐Jong , Talke Frank 
Published: December 2007

AbstractNano‐ and macro‐mechanical properties of ethylene vinyl acetate (EVA) with various amounts of vinyl acetate (VA) have been investigated. Nano‐mechanical properties (modulus and hardness) were obtained using nano‐indentation measurements while macro‐mechanical properties were determined using tensile test measurements. A decrease in Young's modulus and hardness was observed with increasing VA content for both nano‐ and macro‐mechanical measurements. An increase in Young's modulus and hardness was observed as a function of the draw ratio keeping the VA content constant. The difference between macro‐ and nano‐mechanical properties as a function of VA content and draw ratio is explained in terms of crystallinity and chain orientation. POLYM. ENG. SCI., 2008. © 2007 Society of Plastics Engineers
Establishment and growth pattern ofPinus pumilaunder a forest canopy in central Kamchatka
Authors: Okuda Masaki , Sumida Akihiro , Ishii Hiroaki , Vetrova Valentina P. , Hara Toshihiko 
Published: December 2007

AbstractWe investigated the spatial distribution and growth of the Siberian dwarf pine (Pinus pumila) in a valley–foothill larch–birch (Larix cajanderi–Betula platyphyllaas canopy trees) mixed forest of fire origin located in central Kamchatka with the aim of elucidating the ecological features ofP. pumilawhen it is an undergrowth species in a forest. The spatial distribution of all individuals of all tree species was clumped, and the spatial distribution of the two canopy tree species did not repulsively affect that ofP. pumila(i.e., its establishment site). These results suggest that the regeneration ofP. pumiladoes not depend on canopy gaps. However, the analysis using a growth model indicated that the canopy trees negatively affected the growth ofP. pumilaand that the negative effect ofL. cajanderionP. pumilagrowth was stronger than that ofB. platyphylla. The direction of the crown extension ofP. pumilawas weakly related to the open‐space direction. Our results suggest that, although the spatial pattern of establishment ofP. pumilais not repulsed by the distribution of canopy trees, the crown can spread horizontally toward the more sparsely populated areas of the canopy trees where they may have higher growth rates.
Exploring dual identification among Muslim‐American emerging adults: A mixed methods study
Authors: Sirin Selcuk R. , Bikmen Nida , Mir Madeeha , Fine Michelle , Zaal Mayida , Katsiaficas Dalal 
Published: December 2007

ABSTRACTThis mixed methods study explored dual identification among Muslim‐American emerging adults of immigrant origin. A closer look was taken at the relationship between American and Muslim identifications and how this relationship was influenced by experiences of discrimination, acculturative and religious practices, and whether it varied by gender. Data were gathered from 97 Muslim Americans (ages 18–25) who completed a survey and produced identity maps, a pictorial representation of hyphenated identities. The findings showed that young people found a way of allowing their Muslim and American identities to co‐exist, and only a small minority of the participants seemed to experience identity conflict. While religiosity was the only predictor of Muslim identification, young peoples’ identification with mainstream United States culture was predicted by discrimination‐related stress and acculturative practices. Gender moderated the relationship between Muslim and American identities in both survey measures and identity maps.
Long‐term survival in patients older than 80 years hospitalised for heart failure. A 5‐year prospective study
Authors: Mahjoub Haïfa , Rusinaru Dan , Soulière Vicky , Durier Chloé , Peltier Marcel , Tribouilloy Christophe 
Published: December 2007

AbstractBackground:Although heart failure (HF) is frequent in elderly patients, few studies have focused on patients older than 80 years.Aims:To evaluate the clinical features, treatment and long‐term prognosis of HF in patients older than 80 years.Methods and results:Consecutive patients hospitalised for a first HF episode in the Somme Department (France) during 2000 were prospectively included. Of the 799 included patients, 305 (38%) were aged over 80 years. The elderly patients were mostly women with a high prevalence of atrial fibrillation, ischaemic and hypertensive heart disease. Ejection fraction (EF) was assessed in 68.5% of elderly patients and 61% had EF ≥50%. Angiotensin‐converting enzyme inhibitors, beta‐blockers, oral anticoagulants and statins were prescribed less frequently in elderly patients. The 5‐year survival in elderly patients was 19%, dramatically lower than the survival of age‐ and sex‐matched general population (48%). Cardiovascular causes were recorded in over 60% of deaths. On multivariable analysis, cancer, renal insufficiency, old myocardial infarction, diabetes, hyponatraemia and age were predictors of mortality in elderly patients. Reduced EF was a potent predictor of death (HR 1.72, 95%CI 1.24–2.37, p=0.001) in elderly patients.Conclusion:Long‐term prognosis in HF patients older than 80 years is poor, with a dramatic excess mortality compared to the elderly general population. Life‐saving drugs are largely underused in elderly HF patients.