bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of palm ash loading and maleated natural rubber as a coupling agent on the properties of palm‐ash‐filled natural rubber composites
Authors: Ismail H. , Haw F. S. 
Published: September 2008

AbstractNatural rubber composites were prepared by the incorporation of palm ash at different loadings into a natural rubber matrix with a laboratory‐size two‐roll mill (160 × 320 mm2) maintained at 70 ± 5°C in accordance with the method described by ASTM D 3184–89. A coupling agent, maleated natural rubber (MANR), was used to improve the mechanical properties of the natural rubber composites. The results indicated that the scorch time and cure time decreased with increasing filler loading, whereas the maximum torque exhibited an increasing trend. Increasing the palm ash loading increased the tensile modulus, but the tensile strength, fatigue life, and elongation at break decreased. The rubber–filler interactions of the composites decreased with increasing filler loading. Scanning electron microscopy of the tensile fracture surfaces of the composites and rubber–filler interaction studies showed that the presence of MANR enhanced the interfacial interaction of the palm ash filler and natural rubber matrix. The presence of MANR also enhanced the tensile properties and fatigue life of palm‐ash‐filled natural rubber composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Phase behaviors of solid polymer electrolytes/salt system in lithium secondary battery by group‐contribution method: Applicability of the extended Debye‐Hückel theory
Authors: Joo Jae Ho , Bae Young Chan 
Published: September 2008

AbstractA new group‐contribution model based on both the modified double‐lattice theory and the Debye‐Hückel theory extended by Guggenheim theory is developed to interpret the phase behaviors of solid polymer electrolyte/salt systems at various temperatures and compositions. The model includes a combinatorial energy contribution that is responsible for the revised Flory‐Huggins entropy of mixing, the van der Waals energy contribution from dispersion, and the polar force and specific energy contribution from hydrogen bonding. Quantitative description according to the proposed model is in good agreement with the experimentally observed transition temperatures of the given systems. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Polysiloxanes derived from chrysotile asbestos via acid‐leaching and silylation processes
Authors: Habaue Shigeki , Sato Kimiyasu , Yamashita Kiyotsugu , Shimamura Tetsuya , Kaito Masahiro , Masuda Tsuyoshi , Kajiwara Meisetsu 
Published: September 2008

AbstractChrysotile asbestos was transformed into polysiloxanes through processes involving selective acid leaching and the reaction with various silylation reagents. The silylation with trialkoxy(vinyl)silanes followed by adding chlorotrialkylsilane effectively proceeded to afford a polymer with a low‐silanol residue. The obtained polymers were radically crosslinked producing a polymer with a good thermal stability. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Endothelial/lymphocyte activation leads to prominent CD4+ T cell infiltration in the gastric mucosa of patients with systemic sclerosis
Authors: Manetti Mirko , Neumann Elena , Müller Adelheid , Schmeiser Tim , Saar Petra , Milia Anna Franca , Endlicher Esther , Roeb Elke , Messerini Luca , Matucci‐Cerinic Marco , Ibba‐Manneschi Lidia , Müller‐Ladner Ulf 
Published: August 2008

AbstractObjectiveAlthough gastrointestinal tract dysfunction is a common feature in patients with systemic sclerosis (SSc; scleroderma), few studies have addressed the pathogenetic mechanisms of gastrointestinal tract involvement in SSc. We previously showed that severe fibrosis and increased expression of profibrotic cytokines are important hallmarks in the gastric wall of patients with SSc. The aim of the present study was to investigate whether immune and/or microvascular abnormalities may account for tissue damage in gastric wall specimens obtained from patients with SSc.MethodsGastric biopsy samples from 27 patients with SSc and 15 healthy control subjects were analyzed by immunohistochemistry for CD45/leukocyte common antigen, CD3/T cells, CD4/T helper cells, CD8/cytotoxic T cells, CD20/B cells, CD14/monocytes, CD68/macrophages, cell adhesion molecules CD11a/lymphocyte function−associated antigen 1 (LFA‐1), CD49d/very late activation antigen 4 (VLA‐4), CD54/intercellular adhesion molecule 1 (ICAM‐1), CD106/vascular cell adhesion molecule 1 (VCAM‐1), CD31/platelet endothelial cell adhesion molecule 1, and vascular endothelial growth factor (VEGF).ResultsT cell infiltration was a prominent finding in gastric specimens from patients with SSc. The CD4+/CD8+ T cell ratio was significantly increased in SSc specimens compared with controls. T cells were found in both lymphocyte aggregates and diffuse infiltrates and strongly expressed the activation markers VLA‐4, LFA‐1, and ICAM‐1. Endothelial cells showed corresponding surface activation with strong expression of VCAM‐1 and ICAM‐1. Mature B cells were frequently observed arranged in aggregates and rarely were seen in a diffuse pattern. Most lymphocyte aggregates lacked monocyte/macrophages. No difference in microvascular density was observed between SSc specimens and controls. Both SSc and control specimens showed weak or no expression of VEGF.ConclusionOur findings provide the first evidence that endothelial/lymphocyte activation leading to prominent CD4+ T cell infiltration may play a key pathogenetic role within the gastric wall of patients with SSc and may represent an important therapeutic target.
Attributable risk of carpal tunnel syndrome according to industry and occupation in a general population
Authors: Roquelaure Yves , Ha Catherine , Nicolas Guillaume , Pélier‐Cady Marie‐Christine , Mariot Camille , Descatha Alexis , Leclerc Annette , Raimbeau Guy , Goldberg Marcel , Imbernon Ellen 
Published: August 2008

AbstractObjectiveAn epidemiologic surveillance network for carpal tunnel syndrome (CTS) was set up in the general population of a French region to assess the proportion of CTS cases attributable to work in high‐risk industries and occupations.MethodsCases of CTS occurring among patients ages 20–59 years living in the Maine and Loire region were included prospectively from 2002 to 2004. Medical and occupation history was gathered by mailed questionnaire for 815 women and 320 men. Age‐adjusted relative risks of CTS and the attributable risk fractions of CTS among exposed persons (AFEs) were computed in relation to industry sectors and occupation categories.ResultsTwenty‐one industry sectors and 8 occupational categories for women and 10 sectors and 6 occupational categories for men were characterized by a significant excess risk of CTS. High AFE values were observed in the manufacturing (42–93% for both sexes), construction (66% for men), and personal service industries (66% for women) and in the trade and commerce sectors (49% for women). High AFE values were observed in lower‐grade white‐collar occupations for women (43–67%) and blue‐collar occupations for men (60–74%) and women (48–88%).ConclusionThe attributable proportions of CTS cases among workers employed in industry sectors and occupation categories identified at high risk of CTS varied between 36% and 93%.
Subclinical carotid atherosclerosis in patients with psoriatic arthritis
Authors: Tam Lai‐Shan , Shang Qing , Li Edmund K. , Tomlinson Brian , Chu Tanya T. W. , Li Martin , Leung Ying‐Ying , Kwok Lai‐Wa , Wong Kong‐Chiu , Li Tena K. , Yu Tracey , Zhu Tracy Y. , Kun Emily W. , Yip Gabriel W. , Yu Cheuk‐Man 
Published: August 2008

AbstractObjectiveTo examine the prevalence of subclinical atherosclerosis in patients with psoriatic arthritis (PsA) compared with healthy controls, and to identify clinical and biologic markers for atherosclerotic disease in this patient population.MethodsSubclinical atherosclerosis was defined as the average of intima‐media thickness (IMT) measures in the common carotid artery, bifurcation, and internal carotid artery on both sides above the 95th percentile of healthy controls. IMT was measured using carotid ultrasonography in 82 consecutive PsA patients and 82 healthy controls matched on age, sex, and ethnicity. We also ascertained traditional and novel cardiovascular (CV) risk factors, Framingham risk score (FRS), disease severity, treatment, and inflammatory markers in all PsA patients.ResultsNo PsA patients had clinically overt CV diseases. After adjusting for traditional CV risk factors, PsA patients had a higher prevalence of subclinical atherosclerosis. PsA patients with subclinical atherosclerosis had significantly increased sugar, total triglyceride levels, total cholesterol/high‐density cholesterol, white cell count, and patients' global assessment score compared with those without subclinical atherosclerosis. Using logistic regression analysis, independent explanatory variables associated with subclinical atherosclerosis in PsA included increased sugar and total triglyceride levels. The FRS was similar in PsA patients with or without subclinical atherosclerosis. Twenty‐six (35%) of 74 patients had subclinical atherosclerosis despite having a low CV risk.ConclusionPsA is associated with subclinical atherosclerosis after adjusting for traditional CV risk factors. Independent explanatory variables associated with subclinical atherosclerosis in PsA included increased sugar and total triglyceride levels. Carotid IMT can identify PsA patients with subclinical atherosclerosis who may benefit from early intervention.
How accurate are diagnoses for rheumatoid arthritis and juvenile idiopathic arthritis in the general practice research database?
Authors: Thomas S. L. , Edwards C. J. , Smeeth L. , Cooper C. , Hall A. J. 
Published: August 2008

AbstractObjectiveTo identify characteristics that predict a valid rheumatoid arthritis (RA) or juvenile idiopathic arthritis (JIA) diagnosis among RA‐ and JIA‐coded individuals in the General Practice Research Database (GPRD), and to assess limitations of this type of diagnostic validation.MethodsFour RA and 2 JIA diagnostic groups were created with differing strengths of evidence of RA/JIA (Group 1 = strongest evidence), based on RA/JIA medical codes. Individuals were sampled from each group and clinical and prescription data were extracted from anonymized hospital/practice correspondence and electronic records. American College of Rheumatology and International League of Associations for Rheumatology diagnostic criteria were used to validate diagnoses. A data‐derived diagnostic algorithm that maximized sensitivity and specificity was identified using logistic regression.ResultsAmong 223 RA‐coded individuals, the diagnostic algorithm classified individuals as having RA if they had an appropriate GPRD disease‐modifying antirheumatic drug prescription or 3 other GPRD characteristics: >1 RA code during followup, RA diagnostic Group 1 or 2, and no later alternative diagnostic code. This algorithm had >80% sensitivity and specificity when applied to a test data set. Among 101 JIA‐coded individuals, the strongest predictor of a valid diagnosis was a Group 1 diagnostic code (>90% sensitivity and specificity).ConclusionValidity of an RA diagnosis among RA‐coded GPRD individuals appears high for patients with specific characteristics. The findings are important for both interpreting results of published GPRD studies and identifying RA/JIA patients for future GPRD‐based research. However, several limitations were identified, and further debate is needed on how best to validate chronic disease diagnoses in the GPRD.
Lifetime risk of symptomatic knee osteoarthritis
Authors: Murphy Louise , Schwartz Todd A. , Helmick Charles G. , Renner Jordan B. , Tudor Gail , Koch Gary , Dragomir Anca , Kalsbeek William D. , Luta Gheorghe , Jordan Joanne M. 
Published: August 2008

AbstractObjectiveTo estimate the lifetime risk of symptomatic knee osteoarthritis (OA), overall and stratified by sex, race, education, history of knee injury, and body mass index (BMI).MethodsThe lifetime risk of symptomatic OA in at least 1 knee was estimated from logistic regression models with generalized estimating equations among 3,068 participants of the Johnston County Osteoarthritis Project, a longitudinal study of black and white women and men age ≥45 years living in rural North Carolina. Radiographic, sociodemographic, and symptomatic knee data measured at baseline (1990–1997) and first followup (1999–2003) were analyzed.ResultsThe lifetime risk of symptomatic knee OA was 44.7% (95% confidence interval [95% CI] 40.0–49.3%). Cohort members with history of a knee injury had a lifetime risk of 56.8% (95% CI 48.4–65.2%). Lifetime risk rose with increasing BMI, with a risk of 2 in 3 among those who were obese.ConclusionNearly half of the adults in Johnston County will develop symptomatic knee OA by age 85 years, with lifetime risk highest among obese persons. These current high risks in Johnston County may suggest similar risks in the general US population, especially given the increase in 2 major risk factors for knee OA, aging, and obesity. This underscores the immediate need for greater use of clinical and public health interventions, especially those that address weight loss and self‐management, to reduce the impact of having knee OA.
PtII Complexes with 6‐(5‐Trifluoromethyl‐Pyrazol‐3‐yl)‐2,2′‐Bipyridine Terdentate Chelating Ligands: Synthesis, Characterization, and Luminescent Properties
Authors: Chen Jing‐Lin , Chang Sheng‐Yuan , Chi Yun , Chen Kellen , Cheng Yi‐Ming , Lin Chun‐Wei , Lee Gene‐Hsiang , Chou Pi‐Tai , Wu Chen‐Hao , Shih Ping‐I , Shu Ching‐Fong 
Published: September 2008

AbstractA series of PtII complexes Pt(fpbpy)Cl (1), Pt(fpbpy)(OAc) (2), Pt(fpbpy)(NHCOMe) (3), Pt(fpbpy)(NHCOEt) (4), and [Pt(fpbpy)(NCMe)](BF4) (5) with deprotonated 6‐(5‐trifluoromethyl‐pyrazol‐3‐yl)‐2,2′‐bipyridine terdentate ligand are prepared, among which 1 is converted to complexes 2–5 by a simple ligand substitution. Alternatively, acetamide complex 3 is prepared by hydrolysis of acetonitrile complex 5, while the back conversion from 3 to 1 is regulated by the addition of HCl solution, showing the reaction sequence 1→5→3→1. Multilayer OLED devices are successfully fabricated by using triphenyl‐(4‐(9‐phenyl‐9H‐fluoren‐9‐yl)phenyl) silane (TPSi‐F) as host material and with doping concentrations of 1 varying from 7 to 100 %. The electroluminescence showed a substantial red‐shifting versus the normal photoluminescence detected in solution. Moreover, at a doping concentration of 28 %, the device showed a saturated red luminescence with a maximum external quantum yield of 8.5 % at 20 mA cm−2 and a peak luminescence of 47 543 cd m−2 at 18.5 V.
Synthesis, Crystal Structure, Bonding, and Properties of (Ba6O)(OsN3)2
Authors: Schmidt Carsten L. , Wedig Ulrich , Dinnebier Robert , Jansen Martin 
Published: August 2008

AbstractThe new barium nitridoosmate oxide (Ba6O)(OsN3)2 was prepared by reacting elemental barium and osmium (3:1) in nitrogen at 815–830 °C. The crystal structure of (Ba6O)(OsN3)2 as determined by laboratory powder X‐ray diffraction (${R\bar 3}$, No 148: a=b=8.112(1) Å, c=17.390(1) Å, V=991.0(1) Å3, Z=3), consists of sheets of trigonal OsN3 units and trigonal‐antiprismatic Ba6O groups, and is structurally related to the “313 nitrides” AE3MN3 (AE=Ca, Sr, Ba, M=V–Co, Ga). Density functional calculations, using a hybrid functional, likewise indicate the existence of oxygen in the Ba6 polyhedra. The oxidation state 4+ of osmium is confirmed, both by the calculations and by XPS measurements. The bonding properties of the OsN35− units are analyzed and compared to the Raman spectrum. The compound is paramagnetic from room temperature down to T=10 K. Between room temperature and 100 K it obeys the Curie–Weiss law (μ=1.68 μB). (Ba6O)(OsN3)2 is semiconducting with a good electronic conductivity at room temperature (8.74×10−2 Ω−1 cm−1). Below 142 K the temperature dependence of the conductivity resembles that of a variable‐range hopping mechanism.
Stützen‐Deckenknoten für Schleuderbetonstützen
Authors: Rinnhofer Gerhard , Burtscher Stefan L. , Kollegger Johann 
Published: August 2008

AbstractDer vorliegende Artikel behandelt Knoten zwischen hochtragfähigen Schleuderbetonstützen mit Längsbewehrungsgraden bis 14,7% und Deckenplatten aus Normalbeton. Das Augenmerk wird hierbei auf die Durchleitung der Stützenlasten durch die Decke gelegt, wobei auch die Längsbewehrung der Stützen im Knoten unterbrochen ist.Für Schleuderbetonstützen wird eine optimierte Lösung mit einem hochfesten Kern vorgestellt. In Versuchen werden die herkömmlichen Knotendetails und die Ausführung mit hochfestem Kern miteinander verglichen. Es zeigt sich, dass mit der neuen Ausführung nicht nur höhere Lasten erreicht werden können, sondern auch überproportional große Deformationen der Decke, wie dies bei herkömmlichen Ausführungen der Fall sein kann, vermieden werden können. Auf Basis der Versuchdaten wird ein Bemessungsmodell präsentiert, welches in einfacher Weise die Bemessung solcher Knotendetails ermöglicht.
Flexibility of the MHC class II peptide binding cleft in the bound, partially filled, and empty states: A molecular dynamics simulation study
Authors: Yaneva Rakina , Springer Sebastian , Zacharias Martin 
Published: September 2008

AbstractMajor histocompatibility (MHC) Class II cell surface proteins present antigenic peptides to the immune system. Class II structures in complex with peptides but not in the absence of peptide are known. Comparative molecular dynamics (MD) simulations of a Class II protein (HLA‐DR3) with and without CLIP (invariant chain‐associated protein) peptide were performed starting from the CLIP‐bound crystal structure. Depending on the protonation of acidic residues in the P6 peptide‐binding pocket the simulations stayed overall close to the start structure. The simulations without CLIP showed larger conformational fluctuations especially of α‐helices flanking the binding cleft. Largest fluctuations without CLIP were observed in a helical segment near the peptide C‐terminus binding region matching a segment recognized by antibodies specific for empty Class II proteins. Simulations on a Val86Tyr mutation that fills the peptide N‐terminus binding P1 pocket or of a complex with a CLIP fragment (dipeptide) bound to P1 showed an unexpected long range effect. In both simulations the mobility not only of P1 but also of the entire binding cleft was reduced compared to simulations without CLIP. It correlates with the experimental finding that the CLIP fragment binding to P1 is sufficient to prevent antibody recognition specific for the empty form at a site distant from P1. The results suggest a mechanism how a local binding event of small peptides or of an exchange factor near P1 may promote peptide binding and exchange through a long range stabilization of the whole binding cleft in a receptive (near bound) conformation. © 2008 Wiley Periodicals, Inc. Biopolymers 91: 14–27, 2009.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Amyloidogenic potential of α‐chymotrypsin in different conformational states
Authors: Rezaei‐Ghaleh Nasrollah , Zweckstetter Markus , Morshedi Dina , Ebrahim‐Habibi Azadeh , Nemat‐Gorgani Mohsen 
Published: September 2008

AbstractAmyloid fibril formation is widely believed to be a generic property of polypeptide chains. In the present study, α‐chymotrypsin, a well‐known serine protease has been driven toward these structures by the use of two different conditions involving (I) high temperature, pH 2.5, and (II) low concentration of trifluoroethanol (TFE), pH 2.5. A variety of experimental methods, including fluorescence emission, dynamic quenching, steady‐state fluorescence anisotropy, far‐UV circular dichroism, nuclear magnetic resonance spectroscopy, and dynamic light scattering were employed to characterize the conformational states of α‐chymotrypsin that precede formation of amyloid fibrils. The structure formed under Condition I was an unfolded monomer, whereas an α‐helical rich oligomer was induced in Condition II. Both the amyloid aggregation‐prone species manifested a higher solvent exposure of hydrophobic and aromatic residues compared with the native state. Upon incubation of the protein in these conditions for 48 h, amyloid‐like fibrils were formed with diameters of about 10–12 nm. In contrast, at neutral pH and low concentration of TFE, a significant degree of amorphous aggregation was observed, suggesting that charge neutralization of acidic residues in the amyloid core region has a positive influence on amyloid fibril formation. In summary, results presented in this communication suggest that amyloid fibrils of α‐chymotrypsin may be obtained from a variety of structurally distinct conformational ensembles highlighting the critical importance of protein evolution mechanisms related to prevention of protein misfolding. © 2008 Wiley Periodicals, Inc. Biopolymers 91: 28–36, 2009.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Application of a fuzzy logic control system for continuous anaerobic digestion of low buffered, acidic energy crops as mono‐substrate
Authors: Scherer P. , Lehmann K. , Schmidt O. , Demirel B. 
Published: August 2008

AbstractA fuzzy logic control (FLC) system was developed at the Hamburg University of Applied Sciences (HAW Hamburg) for operation of biogas reactors running on energy crops. Three commercially available measuring parameters, namely pH, the methane (CH4) content, and the specific gas production rate (spec. GPR = m3/kg VS/day) were included. The objective was to avoid stabilization of pH with use of buffering supplements, like lime or manure. The developed FLC system can cover most of all applications, such as a careful start‐up process and a gentle recovery strategy after a severe reactor failure, also enabling a process with a high organic loading rate (OLR) and a low hydraulic retention time (HRT), that is, a high throughput anaerobic digestion process with a stable pH and CH4 content. A precondition for a high load process was the concept of interval feeding, for example, with 8 h of interval. The FLC system was proved to be reliable during the long term fermentation studies over 3 years in one‐stage, completely stirred tank reactors (CSTR) with acidic beet silage as mono‐input (pH 3.3–3.4). During fermentation of the fodder beet silage (FBS), a stable HRT of 6.0 days with an OLR of up to 15 kg VS/m3/day and a volumetric GPR of 9 m3/m3/day could be reached. The FLC enabled an automatic recovery of the digester after two induced severe reactor failures. In another attempt to prove the feasibility of the FLC, substrate FBS was changed to sugar beet silage (SBS), which had a substantially lower buffering capacity than that of the FBS. With SBS, the FLC accomplished a stable fermentation at a pH level between 6.5 and 6.6, and a volatile fatty acid level (VFA) below 500 mg/L, but the FLC had to interact and to change the substrate dosage permanently. In a further experiment, the reactor temperature was increased from 41 to 50°C. Concomitantly, the specific GPR, pH and CH4 dropped down. Finally, the FLC automatically enabled a complete recovery in 16 days. Biotechnol. Bioeng. 2009; 102: 736–748. © 2008 Wiley Periodicals, Inc.