bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic viscoelastic properties of fluoroelastomer/clay nanocomposites
Authors: Maiti Madhuchhanda , Bhowmick Anil K. 
Published: September 2007

AbstractNanocomposites based on fluoroelastomer and modified and unmodified sodium montmorillonite clays were prepared. Dynamic mechanical thermal analysis was performed on these nanocomposites over a range of temperatures (−60 to +60°C), frequencies (0.032–32 Hz), and strains (0.002%–2%). The results showed that there were significant changes in the glass transition temperature and storage modulus with the addition of small amount (4 phr) of the modified and the unmodified nanofillers. The tan δ peak heights decreased and the storage modulus increased in general, but it was more prominent in the case of the unmodified clay. With the addition of the nanoclays, the cross‐over point in the double logarithmic plot of storage modulus (E′) and complex viscosity (η*) with frequency, shifted toward higher frequency. Interestingly, with increasing strain, the nanocomposites demonstrated a sudden upturn in the storage modulus after ∼0.2% strain amplitude, because of the formation of α‐crystallization in the elastomer structure. The uniaxial strain before strain sweep experiment increased the storage modulus remarkably. The results were explained with the help of X‐ray diffraction and transmission electron microscopy. POLYM. ENG. SCI., 47:1777–1787, 2007. © 2007 Society of Plastics Engineers
Thermal and mechanical degradation during polymer extrusion processing
Authors: Capone C. , Di Landro L. , Inzoli F. , Penco M. , Sartore L. 
Published: September 2007

AbstractPolymer processing often activates material degradation, which affects to some extent the performance or the life cycle of the obtained products. Polymer degradation is usually evidenced by molecular weight variations as consequence of exposure to high processing temperature and to relevant mechanical stresses. The degrading effects of melt extrusion under different thermo‐mechanical conditions on polymethyl‐methacrylate and polystyrene are investigated. Materials were processed at different temperatures and rates in a single screw extruder and in a capillary rheometer. Processed and as‐received materials were analysed by Gel permeation chromatography, solution viscosity, and melt rheology. Evaluations of molecular weight and rheological behavior changes after processing, as compared with as‐received materials, evidenced the extent of degradation in the different conditions. Experimental analysis was accompanied by finite elements simulation of the polymer flow and heat transmission within the extruder. This allowed an estimation of the expected shear stresses and temperatures distributions, thus indicating potentially critical situations. It was found that the materials processed at the highest rates in extruder presented lowest molecular weight reductions. This was attributed to the shorter residence time in the extruder and to the possibility of wall slip phenomena, which likely reduce the actual shear stress and viscous dissipation in the fast processing conditions. POLYM. ENG. SCI., 47:1813–1819, 2007. © 2007 Society of Plastics Engineers
Controllable fabrication and properties of polypropylene nanofibers
Authors: Wang Dong , Sun Gang , Chiou Bor‐Sen , Hinestroza Juan P. 
Published: September 2007

AbstractThermoplastic nanofibers in yarn form were prepared by melt extrusion of immiscible blends of cellulose acetate butyrate (CAB) and thermoplastic polymers and subsequent removal of the CAB matrix. Isotactic polypropylene (iPP) nanofiber, with diameters ranging from 75 to 375 nm, were made by using CAB/iPP blends, with a ratio of 97.5–2.5, and a hot‐drawn ratio of 25 in a twin‐screw extruder. Dispersion of iPP in CAB and shear and elongational deformation are major factors to result in nanosized fibers. The spheres and nanofibers with different diameters of iPP dispersed phases in the CAB matrix can be well controlled by changing the flow field and the blend ratio. Differential scanning calorimeter and wide angle X‐ray diffraction results showed that the nanofibers had lower crystallinity and crystallite thickness compared with bulk iPP. The atomic force microscopy images presented the well‐defined nanofiber morphology and the excellent manipulability of single iPP nanofiber separated from a bundle of iPP nanofibers. POLYM. ENG. SCI., 47:1865–1872, 2007. © 2007 Society of Plastics Engineers
Development of freeze flow apparatus to study filled polymer melts
Authors: Beard M.A. , Tabor G.R. , Ritchie S.J.K. , Evans K.E. , Walton R.I. 
Published: September 2007

AbstractA novel method to study the distribution of filler particles and polymer orientation of a polymer melt within a capillary die has been developed. Material within the die is quench‐cooled and then removed to provide information about the flow regime at the instant it was frozen. The equipment has been used to examine calcium carbonate‐filled high density polyethylene under high shear. The samples were examined using Energy Dispersive X‐ray Spectrometry (EDS) as well as being studied using X‐ray Diffraction (XRD). The distribution of filler particles across the radius of the capillary has been studied at high and low wall shear rates using EDS. A constant particle distribution across the radius of the die was observed for both flow regimes. The arrangement of crystalline structures within the specimens was examined by XRD. An increase in crystalline order was noticed with increasing wall shear rate. POLYM. ENG. SCI., 47:1937–1942, 2007. © 2007 Society of Plastics Engineers
High‐Tc cuprate superconductivity as a new paradigm
Authors: Won Hyekyung , Morita Yoshifumi , Maki Kazumi 
Published: September 2007

AbstractHigh‐Tc cuprate superconductivity was discovered two decades ago by Bednorz and Müller. Even now the origin and the nature of this remarkable group of superconductors appear to be hotly debated in the literature. However, we believe that a few things are clearly established: (i) the high‐Tc cuprate superconductors in the overdoped region are the BCS d‐wave superconductors (dSC), (ii) the pseudogap phase is a d‐wave spin density wave (dSDW) and (iii) the superconductivity in the underdoped region is gossamer (i.e. dSC in coexistence with dSDW). Here we review these developments and consider a class of nodal superconductors, which share similar phase diagrams to those for high‐Tc cuprate superconductors. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pressure‐induced phenomena in single‐walled carbon nanotubes
Authors: Kuntscher C. A. , Thirunavukkuarasu K. , Pekker Á. , Kamarás K. , Hennrich F. , Kappes M. , Iwasa Y. 
Published: September 2007

AbstractPressure‐dependent transmittance measurements on films of unoriented and oriented single‐walled carbon nanotubes were carried out at room temperature in the midinfrared up to the visible frequency range. The optical transitions in the SWNTs show anomalies at around 2 GPa, which can be attributed to a structural phase transition. The shift to lower frequencies and broadening of the absorption bands with increasing pressure could be attributed to the structural deformation of the SWNTs. We found no indications for a pressure‐induced dimensional crossover in the oriented SWNTs. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rapid mass spectral identification of contryphans. Detection of characteristic peptide ions by fragmentation of intact disulfide‐bonded peptides in crude venom
Authors: Thakur Suman S. , Balaram Padmanabhan 
Published: September 2007

AbstractThe mass spectrometric cleavage of intact disulfide‐bonded peptides in conus venom has been investigated. Contryphans containing a single disulfide bond are shown to fragment preferentially at X–Pro bonds, giving rise to linearized, unsymmetrical cystine peptides, which subsequently fragment by multiple pathways at the disulfide bridge. Cleavage at the disulfide bond can be initiated by initial loss of the CαH or CβH proton, resulting in distinct product ions, with the subsequent loss of elemental sulfur, H2S or H2S2. Contryphans from Conus amadis, Conus loroisii, and Conus striatus are presented as examples, in which detailed assignment of the product ions resulting from tandem mass spectrometric analysis of the intact disulfide is also accomplished. Characteristic fragments arising from conserved contryphan sequences can be used as diagnostic, permitting rapid identification of this class of peptides in crude venom. The observed fragment ions obtained for contryphans in diverse cone snail species are also compared. Copyright © 2007 John Wiley & Sons, Ltd.
Distribution of Traumatic and Other Stressful Life Events by Race/Ethnicity, Gender, SES and Age: A Review of the Research
Authors: Hatch Stephani L. , Dohrenwend Bruce P. 
Published: September 2007

AbstractMuch research has shown that reports of stressful life events are related to a wide variety of psychiatric and physical health outcomes. Relatively little research exists, however, on the distribution of the events according to gender, age, racial/ethnic background, and socioeconomic status (SES). Such information would help identify groups at greatest risk for further investigation. This paper presents a review of the relevant studies. We find that traumatic (e.g., life threatening) events appear to be more frequent for men, while men and women differ more consistently on types rather than on overall numbers of stressful events other than traumatic. Traumatic and other stressful events tend to be more frequent in low SES and racial/ethnic minorities groups, and finally, both traumatic and other stressful events are reported more by younger age groups in samples 18 years of age and older. The limitations and implications of these findings for further research and preventive interventions are discussed, especially the need for more detailed information about individual events.
“We Never was Happy Living Like a Whiteman” : Mental Health Disparities and the Postcolonial Predicament in American Indian Communities
Authors: Gone Joseph P. 
Published: September 2007

AbstractIn the context of increasing attention to disparities in health status between U.S. ethnoracial groups, this article examines the dilemma of divergent cultural practices for redressing disparities in mental health status in American Indian communities. Drawing upon an ethnographic interview with a tribal elder from a northern Plains Indian reservation, a prototypical discourse of distress is presented and analyzed as one exemplar of the divergence between the culture of the clinic and the culture of the community. Situated in the context of continuing power asymmetries between tribal nations and the U.S. federal government, the implications of this cultural divergence for the efforts of mental health professionals, practitioners, and policymakers are identified as a predicament that only the conventions and commitments of a robust community psychology have the potential to resolve.
The involuntary treatment of adolescent psychiatric inpatients—A nation‐wide survey from Finland
Authors: Ellila Heikki Toivo , Sourander Andre , Välimäki Maritta , Warne Tony , Kaivosoja Matti 
Published: September 2007

AbstractThis national cross‐sectional study investigates the prevalence rates, regional differences and factors associated with the involuntary inpatient treatment of adolescents in Finland on a chosen day in 2000. The proportion of inpatients with involuntary legal status was 29.5% (n=82) giving a prevalence rate of 2.5 per 10,000/12–17 years old inhabitants.Forty‐eight per cent of involuntarily inpatients were 16–17 years old and 62% had psychotic disorders. Twenty‐six per cent of inpatients with involuntary legal status were voluntarily admitted. Regional differences of involuntary treatment were rather modest. Psychotic disorders, suicidal acts, and substance use disorders were independently associated with involuntary legal status.There is a need for further studies to investigate the long‐term effects of involuntary treatment on the adolescents’ subsequent well‐being. Further studies on alternatives methods for involuntary treatment are warranted, likewise the clinical guidelines for involuntary treatment practices.
Global ultrasonic system with selective activation for autonomous navigation of an indoor mobile robot
Authors: Yi Soo-Yeong 
Published: September 2007

SUMMARYThis paper presents a global ultrasonic system with selective activation algorithm for autonomous navigation of an indoor mobile robot. The global ultrasonic system consists of several ultrasonic transmitters fixed at reference positions in global coordinates and two receivers at moving coordinates of a mobile robot. By activating the ultrasonic transmitters through an radiofrequency (RF) channel, the robot is able to obtain distance information to the reference positions and localize itself in the global coordinates. Due to limitations in signal strength and beam width, the ultrasonic signals from some transmitters may not be delivered to the robot and the ultrasonic data become invalid. In order to improve the effectiveness of the global ultrasonic system, a so-called selective activation algorithm is developed. Based on the current position of the robot, the selective activation calls a proper ultrasonic transmitter and generates valid ultrasonic data at every sampling instant, resulting in faster, more accurate response for self-localization than does simple sequential activation. Path-following control experiments are conducted to verify the effectiveness of the self-localization based on the proposed selective activation algorithm with the global ultrasonic system.
China's Courts: Restricted Reform
Authors: Liebman Benjamin L. 
Published: September 2007

AbstractChina's courts have in recent years engaged in significant reforms designed to raise the quality of their work. Yet such top-down reforms have been largely technical and are not designed to alter courts' power. Courts have also encountered new challenges, including rising populist pressures, which may undermine their authority. The most important changes in China's courts have come from the ground up: local courts have engaged in significant innovation, and horizontal interaction among judges is facilitating the development of professional identity. Recent developments have largely avoided two central questions facing China's courts: why have courts been permitted to develop even limited new roles, and what additional roles, if any, may they play within the Chinese political system?
Conjugated linoleic acid (CLA) and obesity
Authors: Silveira Manuela-Belén , Carraro Raffaele , Monereo Susana , Tébar Javier 
Published: September 2007

AbstractBackgroundThe term conjugated linoleic acid (CLA) refers to several positional and geometric conjugated dienoic isomers of linoleic acid (LA), of which the trans-10,cis-12 isomer has been reported to reduce adiposity and increase lean mass in mice and other animals when included at ≤1% of the diet. However, most dietary CLA in humans is obtained from dairy products, accounting for the cis-9,trans-11 CLA isomer, also known as rumenic acid, for more than 90% of the total CLA intake. Commercial CLA preparations industrially produced, containing trans-10,cis-12 and cis-9,trans-11 CLA isomers in diverse proportions, are attracting consumers’ interest because of the purported body fat-lowering effects of CLA, coupled to the perception of a ‘natural’ compound devoid of harmful effects. Nevertheless, despite numerous studies on CLA effects on body composition for nearly a decade, the mechanisms by which CLA isomers elicit their effects remain largely unknown. The purpose of this paper is to provide an updated review of the studies performed on animals and humans, as well as to describe the potential mechanisms involved in CLA effects on body weight and composition and metabolism.MethodLiterature review.ResultsExperiments in humans have not been able to show a significant effect on body weight, body composition or weight regain related to either of the CLA isomers. In fact, some studies suggest a tendency towards a decrease in body fat mass and an increase in body lean mass, while some others raise concern about the possibility of deleterious effects of trans-10,cis-12 CLA on lipid profile, glucose metabolism and insulin sensitivity.ConclusionsEvidence regarding effectiveness of CLA in humans is not concluding.
Drugs in the treatment of obesity: sibutramine, orlistat and rimonabant
Authors: Rubio Miguel A , Gargallo Manuel , Isabel Millán Ana , Moreno Basilio 
Published: September 2007

AbstractBackgroundModification of lifestyle is the main therapeutical approach in the treatment of obesity, but use to fail on long terms of time. Addition of anti-obesity drugs allows keeping the weight loss during years and improving obesity-related comorbidities.MethodsThis review is an actualisation on efficacy, safety and tolerability of the approved drugs on the long-term treatment of obesity (orlistat and sibutramine). New indications and effects of their use far beyond the weight loss are as well commented. Finally, potential benefits of the administration of CB1 antagonist rimonabant on the weight loss and cardiometabolic risk factors are analysed in detail.DiscussionA decade of experience on the use of orlistat and sibutramine has demonstrated their higher efficacy on the weight loss when compared to placebo either on adult or teenage population as well as safety and tolerability on long-term administration. Beneficial effects on the lipid profile, glycosilated haemoglobin on diabetic patients, blood pressure and levels of inflammatory cytokines, contribute to decrease the cardiovascular risk on obese patients. Phase III clinical trials using rimonabant show additional benefits to the expected weight loss, mainly reducing visceral fat and cardiometabolic risk factors.ConclusionPharmacological treatment of obesity must be considered as a therapeutical tool that has to be used together with long-term lifestyle changes, contributing to the body weight reduction as well as to the improvement of the cardiometabolic risk related to obesity.
Critical Difference Table for Word Recognition Testing Derived Using Computer Simulation
Authors: Carney Edward , Schlauch Robert S. 
Published: September 2007

PurposeTo construct a table for upper and lower limits of the 95% critical range for changes in word recognition scores obtained with monosyllabic word lists (of lengths 10, 25, 50, and 100 words) using newly available methods. Although such a table has been available for nearly 30 years (A. R. Thornton & M. J. M. Raffin, 1978), the earlier table was constructed by calculation and used an approximation to the variance of the difference score between 2 administrations of word lists of identical size. It has been used clinically, reproduced, and recommended for use by clinicians in handbooks and textbooks.MethodThe new table was created using computer simulation of the relevant distributions and a direct estimate of the variance of the difference score between 2 tests, calculated using the simulated results.ResultsThe new table differed from the previous table in 23% of entries. Critical ranges were both narrowed (82%) and expanded (18%). No range changed by more than 1 word correct in any direction. The original table was most accurate for list sizes of 25 words each.ConclusionUsing the new table will provide more accurate estimates of the 95% critical range for successive administrations of word recognition tests.
Contribution of Two Sources of Listener Knowledge to Intelligibility of Speakers With Cerebral Palsy
Authors: Hustad Katherine C. 
Published: September 2007

Purpose
This study examined the independent and combined effects of two sources of linguistic knowledge (alphabet cues and semantic predictability) on the intelligibility of speakers with dysarthria. The study also examined the extent to which each source of knowledge accounted for variability in intelligibility gains.

Method
Eight speakers with cerebral palsy and dysarthria contributed speech samples, and 128 listeners transcribed the speech samples (16 listeners per speaker) in 4 different conditions (no cues and unpredictable sentences; no cues and predictable sentences; alphabet cues and unpredictable sentences; alphabet cues and predictable sentences). Listener transcription results were the dependent variable and were scored as the percentage of words identified correctly by listeners.

Results
Both alphabet cues and semantic predictability made independent and overlapping contributions to intelligibility. In addition, alphabet cues accounted for more of the variability in gain scores than semantic predictability. Inseparable joint effects from the two sources of knowledge also made an important contribution to intelligibility.

Conclusion
Alphabet cues may be a more powerful source of information for resolving lexical ambiguity than semantic predictability for listeners who are faced with dysarthric speech.
Acquisition of English Grammatical Morphology by Native Mandarin-Speaking Children and Adolescents: Age-Related Differences
Authors: Jia Gisela , Fuse Akiko 
Published: September 2007

Purpose

This 5-year longitudinal study investigated the acquisition of 6 English grammatical morphemes (i.e., regular and irregular past tense, 3rd person singular, progressive aspect –
ing
, copula BE, and auxiliary DO) by 10 native Mandarin-speaking children and adolescents in the United States (arrived in the United States between 5 and 16 years of age). The goals were to chart and compare the acquisition trajectories and levels of mastery across the morphemes, identify when age-related differences emerged and which forms they took.

Method
Morphological proficiency was measured by the accuracy of these morphemes in obligatory contexts during spontaneous speech.

Results
The morphemes were mastered by different numbers of participants and showed different growth trajectories. Performance variance was partially predicted by age of arrival (AoAr) in the United States, with early arrivals achieving greater proficiency than late arrivals. However, such AoAr effects took several years to occur and only existed for 2 of the 6 morphemes (i.e., 3rd person singular and regular past tense). Growth curve analysis revealed that language environment was a stronger predictor of individual differences than AoAr. Results did not uncover age-related differences in the acquisition of tense versus non-tense-related morphemes, nor in regular versus irregular morphemes, nor in the error types.

Conclusion
Findings support an Environmental account for age-related differences in 2nd language (L2) morphological acquisition. Results also indicate that the acquisition of some grammatical morphemes by school-aged immigrants takes several years to complete. As L2 learners exhibit some error types and difficulties similar to monolingual children with specific language impairment, caution needs to be taken when interpreting and using morphological errors as indicators of speech/language learning problems in this population.