bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pore‐filling electrolyte membranes based on microporous polyethylene matrices activated with plasma and sulfonated hydrogenated styrene butadiene block copolymer. Synthesis, microstructural and electrical characterization
Authors: Navarro Amparo , del Río Carmen , Acosta José Luis 
Published: July 2008

AbstractIn this research a series of pore‐filling electrolyte membranes were prepared, based on a sulfonated and hydrogenated styrene/butadiene block copolymer (SHSBS) and plasma‐treated microporous polyethylene (PE) membranes. The pore‐filling electrolyte membranes were characterized by means of scanning electronic microscopy (SEM), infrared spectroscopy (FTIR‐ATR), and dynamic mechanical analysis (DMA). In addition, the water uptake and methanol/water uptake capacities of these membranes were determined using several methanol in water solutions, as well as the permeability coefficients, for both water and methanol, using a 2 M methanol in water solution and pure methanol. Finally, electrical behavior was recorded by means of electrochemical impedance spectroscopy (EIS) and the four probe technique (FPT). The SEM images recorded show good coating of the pore‐filling electrolyte membranes on the plasma‐treated PE matrices, and DMA shows the proper relaxations of the two components: PE and SHSBS. Furthermore, the methanol/water absorption capacity was observed to diminish with plasma treatment of the matrix. Methanol permeability of the pore‐filling electrolyte membranes is notably lower than that of the Nafion® membrane, ion conductivity moving in the order of 10−2 S cm−1. Both of these characteristics qualify the experimental membranes as candidates to be applied as proton exchangers in fuel cells (FCs). © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1684–1695, 2008
3D diamond‐containing nanocomposites based on hybrid polyurethane–poly(2‐hydroxyethyl methacrylate) semi‐IPNs: Composition‐nanostructure‐segmental dynamics‐elastic properties relationships
Authors: Karabanova L. V. , Bershtein V. A. , Sukhanova T. E. , Yakushev P. N. , Egorova L. M. , Lutsyk E. D. , Svyatyna A. V. , Vylegzhanina M. E. 
Published: July 2008

AbstractNanostructure, glass transition dynamics and elastic properties were studied in the 3D nanodiamond‐containing composites based on polyurethane‐poly(2‐hydroxyethyl methacrylate) semi‐interpenetrating polymer networks (PU‐PHEMA semi‐IPNs), neat PU or PHEMA matrices. Nanodiamond (ND) content in the nanocomposites varied from 0.25 to 3 wt %. Combined differential scanning calorimetry/ laser‐interferometric creep rate spectroscopy/atomic force microscopy approach was utilized. A large impact of small 3D ND additives on PU‐PHEMA networks' dynamics and properties was revealed under conditions when an average inter‐particle distance L exceeds by far gyration radius Rg. The pronounced heterogeneity of glass transitions' dynamics and two opposite effects were observed. The main effect was a strong suppression of PHEMA glass transition dynamics at 90–180 °C, with the enhancement of creep resistance and threefold to sixfold increasing modulus of elasticity. The peculiarly crosslinked structure of nanocomposites, due to double covalent hybridization, resulted in low rheological percolation threshold, and a synergistic effect in dynamics was observed. Less pronounced effect of accelerating dynamics in the temperature region between β‐ and α‐transitions in PHEMA was associated with dynamics in domains with loosened molecular packing. The distinct physical limit for “anomalous” decreasing Tg is predicted in terms of the notion of the common segmental nature of α‐ and β‐relaxations. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1696–1712, 2008
Thermo‐ and pH‐induced phase transitions and network parameters of poly(N‐isopropylacrylamide‐ co‐2‐acrylamido‐2‐methyl‐propanosulfonic acid) hydrogels
Authors: Turan Eylem , Demirci Serkan , Caykara Tuncer 
Published: July 2008

AbstractDual temperature‐ and pH‐sensitive hydrogels composed of N‐isopropylacrylamide (NIPAM) and 2‐acrylamido‐2‐methyl‐propanosulfonic acid (AMPS) were prepared by free‐radical crosslinking copolymerization in aqueous solution at 22 °C. The mole percent of AMPS in the comonomer feed was varied between 0.0 and 7.5, while the crosslinker ratio was fixed at 5.0/100. The effect of AMPS content on thermo‐ and pH‐ induced phase transitions as well as equilibrium swelling/deswelling, interior morphology and network structure was investigated. The volume phase transition temperature (VPT‐T) was determined by both swelling/deswelling measurements and differential scanning calorimetry (DSC) technique. In addition, the volume phase transition pH (VPT‐pH) was detected from the derivative of the curves of the swelling ratio (dQv/dpH) versus pH. The polymer‐solvent interaction parameter (χ) and the average molecular mass between crosslinks ($\overline M_{\rm c}$) of hydrogels were calculated from swelling ratios in buffer solutions at various pHs. The enthalpy (ΔH) and entropy (ΔS) changes appearing in the χ parameter of hydrogels were also determined by using the modified Flory–Rehner equation. The negative values for ΔH and ΔS indicated that the hydrogels had a negative temperature‐sensitive property in water, that is, swelling at a lower temperature and shrinking at a higher temperature. It was observed that the experimental swelling data of hydrogels at different temperature agreed with the modified Flory‐Rehner approach based on the affine network model. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1713–1724, 2008
Crystallization behavior and morphological development of isotactic polypropylene with an aryl amide derivative as β‐form nucleating agent
Authors: Dong Mu , Guo Zhaoxia , Yu Jian , Su Zhiqiang 
Published: July 2008

AbstractThis article reports crystallization behaviors of isotactic polypropylene (iPP) with an aryl amide derivative (TMB‐5) as β‐form nucleating agent. The effects of nucleating agent concentration, thermal history and assemble morphology of nucleating agent on the crystallization behaviors of iPP were studied by differential scanning calorimetry, X‐ray diffraction, and polarized optical microscopy. The results indicated that the TMB‐5 concentration should surpass a threshold value to get products rich in β‐iPP. The diverse morphologies of TMB‐5 are determined by nucleating agent concentration and crystallization condition. At higher concentrations, the recrystallized TMB‐5 aggregates into needle‐like structure, which induces mixed polymorphic phases on the lateral surface and large amount of β modification around the tip. High β nucleation efficiency was obtained at the lowest studied crystallization temperature, which is desirable for real molding process. TMB‐5 prefers to recrystallize from the melt at higher concentration and lower crystallization temperature. The difference in solubility, pertinent to concentration and crystallization temperature, determined the distinct crystallization behaviors of iPP. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1725–1733, 2008
Influence of α‐ZrP fillers and process conditions on the morphology and the gas barrier properties of filled polyamide 6 films
Authors: Olivier L. , Sabard M. , Fulchiron R. , Espuche E. , David L. , Guiu A. 
Published: July 2008

AbstractComposite films based on polyamide 6 and lamellar unmodified α‐ZrP nanofillers have been prepared for low filler amounts (less than 2 wt %) using cast process or blowing process. Whatever be the filler content and the film process conditions, the lamellar nanofillers were not intercalated by the polymer chains and microcomposites were obtained. On the other hand, the matrix crystalline structure highly depended on the presence of fillers and on the film process conditions. The nature of the crystalline phase and its orientation were shown to play a major role on the film barrier properties to helium. For instance, the presence of γ crystalline phase associated to a specific orientation of the crystalline lamellae parallel to the film surface could significantly contribute to enhance barrier properties. This specific morphology was favored by the presence of α‐ZrP in the formulation but depended also on the process conditions. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1734–1746, 2008
Fabrication and characteristics of SiOx ‐core nanowires: Comparison study between uncoated and ZnO‐coated SiOx nanowires
Authors: Kim Hyoun Woo , Shim Seung Hyun , Kong Myung Ho , Yang Hack‐Hui 
Published: July 2008

AbstractWe have demonstrated an approach to the synthesis of SiOx ‐core nanowires, on which ZnO shell layer would be subsequently deposited. We have discussed the possible growth mechanism of SiOx nanowires, in regard to the role of Au catalyst. For a comparison study between uncoated and coated nanowires, samples were characterized by X‐ray dif‐ fraction (XRD), transmission electron microscopy (TEM), and photoluminescence spectroscopy (PL). This method can be applied to a wide range of materials and results in various heterostructures, which may serve as potential building blocks in various nanodevices. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Amorphous Sn–Ga–Zn–O channel thin‐film transistors
Authors: Ogo Youichi , Nomura Kenji , Yanagi Hiroshi , Kamiya Toshio , Hirano Masahiro , Hosono Hideo 
Published: July 2008

AbstractTransparent amorphous oxide semiconductors (TAOS) such as a‐InGaZnO4 are expected to be applied for channels of low‐temperature high‐mobility thin‐film transistors (TFTs). This paper presents the fabrication and characteristics of amorphous Sn–Ga–Zn–O (a‐SGZO) channel TFTs. Bottom‐gate TFTs were fabricated using as‐deposited and annealed a‐SGZO channels on a‐SiO2/n+‐Si wafers. Contrary to a‐InGaZnO4 channel TFTs, the device performances of the as‐deposited channel TFTs were very poor, e.g., on‐currents (Ion) were <10–7 A and on/off current ratios (Ron/off) were <101. The TFTs using channels annealed at 500 °C showed good performances such as Ion > 10–5 A, Ron/off > 106 and μsat ∼ 1.8 cm2 V–1 s–1. Optical measurements indicate that the improvement is accompanied by a reduction of the density of subgap states. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The role of source and drain material in the performance of GIZO based thin‐film transistors
Authors: Barquinha P. , Vilà A. , Gonçalves G. , Pereira L. , Martins R. , Morante J. , Fortunato E. 
Published: July 2008

AbstractIndium tin oxide (ITO) has been used as the prefered electrode material for the emerging area of transparent electronics, namely for thin‐film transistors (TFTs) based on oxide semiconductors. This work pretends to investigate different materials to replace ITO in inverted‐staggered TFTs based on gallium–indium–zinc oxide (GIZO), one of the most promissing oxide semiconductors for TFTs. The analyzed electrode materials are indium–zinc oxide (IZO), Ti, Mo and Ti/Au. Devices are analyzed with special focus on the contact resistance fundamentals, including the extraction of source/ drain series resistances and TFTs intrinsic parameters, such as intrinsic mobility (µi) and intrinsic threshold voltage (VTi). The obtained contact resistance values are between 10 kΩ and 20 kΩ, and the best devices have field effect mobility (µFE) close to 25 cm2/V s and on/off ratio close to 108. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Robustness properties of Cuscore statistics for monitoring a nonstationary system
Authors: Valverde‐Ventura René , Nembhard Harriet Black 
Published: July 2008

AbstractWe investigate the performance of cumulative score (Cuscore) charts in monitoring a nonstationary process subject to minimum mean‐squared error (MMSE) feedback control. Specifically, we have previously designed Cuscore statistics to discover spike or step signals hidden in a nonstationary noise disturbance for feedback‐controlled processes. Here, we study the properties of the proposed policies in terms of their robustness to process model misspecification, to deviations from assumed values for their parameters, to model misspecification for the disturbance as well as to model misspecification for the signal. We found that, in general, the Cuscore charts are fairly robust to process and signal model misspecification. However, they are less robust to departures from its true parameter values. We present a numerical example to demonstrate the importance of understanding the Cuscore's robustness as well as its construction and application. Copyright © 2008 John Wiley & Sons, Ltd.
Rehabilitation nurses' experiences providing spiritual care
Authors: Gebhardt Mary Catherine 
Published: July 2008

AbstractThe purpose of this phenomenological study was to examine rehabilitation nurses' experiences providing spiritual care. Rehabilitation nurses provide care for patients and their families after life‐threatening events and are in a unique position to meet holistic health care needs. Little is written about rehabilitation nurses' perceptions of providing spiritual care. Fourteen rehabilitation nurses self‐identified as providing spiritual care and agreed to participate in individual interviews. The interviews focused on the nurses' definition of spiritual care, interventions the nurses perceived as spiritual and their comfort in providing spiritual care. More studies are needed to determine if providing spiritual care improves patient outcomes. Copyright © 2008 John Wiley & Sons, Ltd.
A method for estimation of urea using ammonia electrode and its applicability to milk samples
Authors: Sharma Rajan , Rajput Yudhishthir S , Kaur Sumandeep , Tomar Sudhir K 
Published: July 2008

A method for the estimation of urea in milk using ammonia electrode is described. Urea is first degraded by urease enzyme into ammonium ion and carbon dioxide at neutral pH. The ammonium ion is then converted into ammonia at alkaline pH. A linear inverse relationship was observed between logarithmic concentration of ammonia or urea and electrode response. Repeatability, expressed as a coefficient of variation, was 1·77% at a level of 8·92 mm-urea in milk. The method was validated in milk samples spiked with between 2×10−3and 10×10−3 m-urea and recovery of added urea was quantitative. Whereas, preservative sodium azide at 0·5 g/l or 2 g/l level did not affect results, lower values of urea concentration in presence of Bronopol at 0·5 g/l were observed. Urea levels in milk samples estimated by this method were comparable to standard enzymatic method. The method is simple, fast and is not prone to interference from other milk constituents.
Physical Activity Patterns During Weight Maintenance Following a Low‐energy Density Dietary Intervention
Authors: Cox Tiffany L. , Malpede Christie Z. , Desmond Renee A. , Faulk Lori E. , Myer Rory A. , Henson C. Suzanne , Heimburger Douglas C. , Ard Jamy D. 
Published: July 2008

AbstractObjective: The objective was to determine the role of physical activity (PA) and energy intake on weight maintenance among former University of Alabama at Birmingham EatRight Weight Management Program participants.Research Methods and Procedures: Eighty‐nine former participants completed follow‐up visits ≥1 year after completing EatRight. BMI was calculated using measured height and weight. Diet intake was estimated from 4‐day food records. PA was assessed using a module from the Behavioral Risk Factor Surveillance System Survey. Cut‐off points were chosen based on the distribution of minutes of activity. For moderate and total activity, cut‐off points were 0, 1 to 30, 31 to 60, and >60 minutes. For vigorous activity, the categories were 0, 1 to 20, 21 to 30, and >30 minutes. General linear models determined the association of PA with change in weight at follow‐up controlling for gender and total energy intake (kcal/d).Results: At follow‐up, 80% (n = 71) of participants maintained (regained <5% of program end weight) their body weight and 20% had gained weight. Mean weight change was 1.0 ± 6.5 kg. Maintainers consumed 384 fewer kcal/d on average. Maintainers had a lower energy density dietary pattern (1.58 vs. 2.01 kcal/g, p < 0.01). There was no significant difference in PA min/d reported by maintainers and gainers.Discussion: Our results suggest that, despite being minimally active, weight‐reduced individuals can successfully maintain their newly achieved body weight with appropriate caloric intake. Adopting a lower calorie, low energy density dietary pattern may reduce the amount of PA that is truly necessary for weight maintenance.
Association of Cigarettes Smoked Daily with Obesity in a General Adult Population
Authors: Chiolero Arnaud , Jacot‐Sadowski Isabelle , Faeh David , Paccaud Fred , Cornuz Jacques 
Published: July 2008

AbstractObjective: We analyzed the cross‐sectional association between obesity and smoking habits, taking into account diet, physical activity, and educational level.Research Methods and Procedures: We used data from the 2002 Swiss Health Survey, a population‐based cross‐sectional telephone survey assessing health and self‐reported health behaviors. Reported smoking habits, height, and weight were available for 17,562 subjects (7844 men and 9718 women) ≥25 years of age. BMI was calculated as (self‐reported) weight divided by height2.Results: Mean BMI was 25.1 kg/m2 for non‐smokers, 26.1 kg/m2 for ex‐smokers, 24.6 kg/m2 for light smokers (1 to 9 cigarettes/d), 24.8 kg/m2 for moderate smokers (10 to 19 cigarettes/d), and 25.3 kg/m2 for heavy smokers (≥20 cigarettes/d) in men and 24.0, 24.1, 22.9, 22.9, and 23.3 kg/m2, respectively, in women. Obesity (BMI ≥ 30 kg/m2) was increasingly frequent with older age, lower physical activity, lower fruits/vegetables intake, and lower educational level. Compared with non‐smokers, the odds ratio for obesity vs. normal weight (BMI = 18.5 to 25.0 kg/m2) adjusted for age, nationality, educational level, leisure time physical activity, and fruit/vegetable intake were 1.9 (95% confidence interval: 1.5 to 2.3) for ex‐smokers, 0.5 (0.3 to 0.8) for light smokers, 0.7 (0.4 to 1.0) for moderate smokers, and 1.3 (1.0 to 1.7) for heavy smokers in men and 1.3 (1.1 to 1.6), 0.7 (0.5 to 1.0), 0.8 (0.5 to 1.0), and 1.1 (0.8 to 1.4), respectively, in women.Discussion: Among smokers, obesity was associated in a graded manner with the number of cigarettes daily smoked, particularly in men. More emphasis should be put on the risk of obesity among smokers.
Evaluation of Risk Profiles by Subcutaneous Adipose Tissue Topography in Obese Juveniles
Authors: Moeller Reinhard , Horejsi Renate , Pilz Stefan , Lang Nicole , Sargsyan Karine , Dimitrova Roumiana , Tafeit Erwin , Giuliani Albrecht , Almer Gunter , Mangge Harald 
Published: July 2008

AbstractObjective: To compare subcutaneous adipose tissue topography (SAT‐top) in obese juveniles with age‐matched normal‐weight controls.Research Methods and Procedures: The optical device LIPOMETER (European Patent EP 0516251) enables the non‐invasive, rapid, safe, and precise measurement of the thickness of subcutaneous adipose tissue. Fifteen defined body sites (1 = neck to 15 = calf) characterize the individual SAT‐top like an individual fingerprint. SAT‐top of 1351 juveniles (obese: 42 boys, 59 girls, normal weight: 680 boys, 570 girls) from 7 to 19 years of age were measured. For visual comparison, the 15‐dimensional SAT‐top information was condensed by factor analysis into a two‐dimensional factor plot.Results: Both female and male obese juveniles had markedly increased adipose tissue layers at 7 = upper abdomen, 8 = lower abdomen, 5 = front chest, and 6 = lateral chest. The pubertal changes of body shape and fat distribution of the normal‐weight boys and girls (boys show thinner adipose tissue layers on their legs, whereas girls had thicker adipose tissue layers at the extremities) were not seen in the obese group. Independently of age and sex, all of the obese juveniles showed a similar, more android body fat distribution with increased trunk fat.Discussion: SAT‐top of the obese juveniles is similar to that of patients with type 2 diabetes, polycystic ovary syndrome, and coronary heart disease. Patients with these metabolic disorders and obese juveniles are located in the factor plot in the same area. This body shape may indicate a risk profile for developing polycystic ovary syndrome (women), type 2 diabetes, and early atherosclerosis (both sexes).
Trends in the Prevalence of Overweight and Obesity among Young Australians, 1985, 1997, and 2004
Authors: Booth Michael L. , Dobbins Timothy , Okely Anthony D. , Denney‐Wilson Elizabeth , Hardy Louise L. 
Published: July 2008

AbstractObjective: To determine secular trends in overweight/obesity among 7‐ to 15‐year‐olds for the periods 1985, 1997, and 2004.Research Method and Procedures: Data from representative surveys conducted in New South Wales, Australia, in 1985, 1997, and 2004 were analyzed. Height and weight were measured, and BMI categories were created using International Obesity Task Force definitions. Students were grouped as Grades 2 + 4 + 6 and 8 + 10.Results: The prevalences of overweight/obesity for 1985, 1997, and 2004 were 10.9%, 20.6%, and 25.7% among the younger boys and 10.6%, 19.5%, and 26.1% among the older boys. The average annual rate of increase for 1985 to 1997 was 0.81% and for 1997 to 2004 was 0.73% among the younger boys and was 0.74% and 0.94% for the two periods among the older boys. The prevalences of overweight/obesity in 1985, 1997, and 2004 were 14.0%, 22.0%, and 24.8% among the younger girls and 8.3%, 17.9%, and 19.8% among the older girls, respectively. The average annual rates of increase for the two periods were 0.8% and 0.4% among the younger girls and 0.80% and 0.27% among the older girls. Change in the prevalence of overweight/obesity and socioeconomic status were not associated.Discussion: Over the period 1985 to 1997, the prevalence of overweight and obesity increased significantly among the younger and older boys and the younger girls. The prevalence of overweight, but not obesity, increased among the older girls over this period. Over the period 1997 to 2004, the prevalence of overweight/obesity combined increased significantly among boys of both age groups but not among girls.
Potential of Intestinal Electrical Stimulation for Obesity: A Preliminary Canine Study
Authors: Yin Jieyun , Ouyang Hui , Chen Jiande D.Z. 
Published: July 2008

AbstractObjective: The aims of this study were to investigate the therapeutic potential of intestinal electrical stimulation (IES) for obesity. Experiments were performed to investigate the effects of IES on food intake, gastric tone, gastric accommodation, and its possible pathway.Research Methods and Procedures: Ten normal dogs and six dogs with truncal vagotomy were used in this study. Each dog was equipped with a gastric cannula for the measurement of gastric tone and accommodation by barostat and one pair of duodenal serosal electrodes for IES. The experiment on food intake was composed of both control session without IES and IES session after a 28‐hour fast. The experiment on gastric tone and accommodation was performed in the fasting and fed states and composed of three sessions: control, IES, and IES with NG‐nitro‐l‐arginine.Results: IES significantly reduced food intake in the normal dogs (459.0 vs. 312.6 grams, p < 0.001). The food intake was negatively correlated with the fasting gastric volume during IES. IES significantly decreased fasting gastric tone in the normal dogs reflected as a decrease in gastric volume (89.1 vs. 261.3 mL, p < 0.01), which was abolished by vagotomy and NG‐nitro‐l‐arginine.Discussion: IES reduces food intake and inhibits gastric tone in the fasting state. The inhibitory effect of IES on gastric tone is mediated by both vagal and nitrergic pathway.