bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel polycaprolactone‐grafted‐carbon black nanocomposite‐based sensor for detecting solvent vapors
Authors: Cheng Jianguo , Wang Li , Huo Jia , Yu Haojie 
Published: April 2011

AbstractA novel vapor sensor is fabricated with polycaprolactone‐grafted‐carbon black (CB‐g‐PCL) as sensing materials. The influence of PCL with different grafting contents and solvents with various solubility and concentrations including benzene, deionized water, epoxy chloropropane (ECP), ethanol, toluene, and tetrahydrofuran on the response of electric resistance was investigated. When compared with mixture of PCL and carbon black, the CB‐g‐PCL‐based sensor shows high sensitivity and good reproducibility. Sensor with moderate content of grafting PCL showed high sensitivity to vapors. The electric resistance of sensor drastically increased in ECP, ethanol, and deionized water with similar solubility with PCL and showed slight increase in benzene, toluene, and tetrahydrofuran with different solubility. The study on the response of electric resistance of CB‐g‐PCL to different vapors confirmed the swelling‐induced sensing mechanism of sensor based on polymer‐grafted‐conductive nanomaterials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Proton conducting crosslinked polymer electrolyte membranes based on SBS block copolymer
Authors: Roh Dong Kyu , Koh Jong Kwan , Chi Won Seok , Shul Yong Gun , Kim Jong Hak 
Published: April 2011

AbstractA series of crosslinked polymer electrolyte membranes with controlled structures were prepared based on poly(styrene‐b‐butadiene‐b‐styrene) (SBS) triblock copolymer and a sulfonated monomer, 2‐sulfoethyl methacrylate (SEMA). SBS membranes were thermally crosslinked with SEMA in the presence of a thermal‐initiator, 4,4′‐azobis(4‐cyanovaleric acid) (ACVA), as confirmed by FT‐IR spectroscopy. The water uptake and ion exchange capacity (IEC) of membranes increased almost linearly with SEMA concentrations due to the increase of SO groups. However, the proton conductivity of membranes increased linearly up to 33 wt % of SEMA, above which it abruptly jumped to 0.04 S/cm presumably due to the formation of well‐developed proton channels. Microphase‐separated morphology and amorphous structures of crosslinked SBS/SEMA membranes were observed using wide angle X‐ray scattering (WAXS), small angle X‐ray scattering (SAXS), and transmission electron microscopy (TEM). The membranes exhibited good mechanical properties and high thermal stability up to 250°C, as determined by a universal testing machine (UTM) and thermal gravimetric analysis (TGA), respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Structural parameters in relation to the rheological behavior and properties of PP/EPR in‐reactor alloy synthesized by multi‐stage sequential polymerization
Authors: Bagheri H. , Nekoomanesh M. , Hakim S. , Jahani Y. , Fan Z. Q. 
Published: April 2011

AbstractThe morphology and molecular structure of an in‐reactor polypropylene/ethylene propylene rubber alloy, synthesized by multi‐stage sequential polymerization, were studied with respect to the rheological behavior and final properties of the alloy. The polymer alloys, based on different structural morphologies, were characterized by SEM, GPC, 13C NMR, DSC, rheological analysis, and mechanical testing. The scanning electron microscopy of samples showed that the size of the dispersed phase particles is decreased as the switch frequency of copolymerization timing is increased. The GPC results showed that switch frequency slightly altered the molecular weight distribution of the copolymer although it had no effect on PP homopolymer. 13C NMR results were used for the evaluation of compatibility between the two phases with changes in switch frequency. DSC results showed that Tm and Tc were almost independent of switch frequency, even though the size of dispersed phase was decreased and the blend crystal content increased with ΔH of about 13%. The small amplitude oscillation rheometry showed that storage modulus and viscosity shifted to higher values when switch frequency increased. In studying the mechanical properties it was revealed that, especially the impact strength increased by about 62% when the size of the dispersed particles was decreased. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Comparison of the toughening effects of different elastomers on nylon 1010
Authors: Yu Haiyang , Zhang Yong , Ren Wentan , Hoch Martin , Guo Sharon 
Published: April 2011

AbstractThe toughness of three different elastomer‐toughened nylon 1010 blends was investigated via standard notched Izod impact test and single edge notched three‐point bending test. The toughness of nylon 1010 blends varies much with different elastomer types and components. All three kinds of nylon/elastomer/maleated‐elastomer blends showed high impact strength (over 50 kJ m−2) as long as at appropriate blending ratios. With increasing maleated elastomer content, brittle‐ductile transition was observed for all three kinds of elastomer‐toughened nylon 1010 blends. The number average dispersed particle size (dn) of ethylene‐1‐octene copolymers or ethylene‐vinyl acetate copolymers toughened nylon 1010 blends significantly decreased from over 1 to 0.1 μm with increasing corresponding maleated elastomer content. Investigation on the fracture toughness showed the dissipative energy density gradually increased with decreasing dn, while the limited specific fracture energy increased with increasing dn when dn was below 1 μm and then sharply decreased with further increasing dn. The energy consumed in the outer plastic zone was the main part of the whole energy dissipated during the fracture process. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Enhancing protein resistance of hydrogels based on poly(2‐hydroxyethyl methacrylate) and poly(2‐methacryloyloxyethyl phosphorylcholine) with interpenetrating network structure
Authors: Wang Jingjing , Li Xinsong 
Published: April 2011

AbstractIn this work, sequential interpenetrating polymer networks (IPNs) based on poly(2‐hydroxyethyl methacrylate) (PHEMA) and poly (2‐methacryloyloxyethyl phosphorylcholine) (PMPC) were prepared with improved protein resistance. The bulk properties of the IPN hydrogels such as water content, ion permeability and mechanical strength were determined by the gravimetric method, ionoflux measurement technique and tensile tester respectively. The surface characteristics of the IPNs were investigated by X‐ray photoelectron spectroscopy (XPS) and contact angle measurements. XPS analysis suggested that PMPC was present on the surface and in the bulk material. The IPN hydrogels possessed more hydrophilic surface than PHEMA revealed by contact angle measurements. Bovine serum albumin was used as a model protein to evaluate protein resistance by bicinchoninic acid assay method. The result revealed that the protein adsorption on the IPNs showed dramatically reduction compared to PHEMA. These results suggest that the IPNs based on PHEMA and PMPC may be further developed as ophthalmic biomaterials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of the nucleation mechanism on complex poly(L‐lactide) nonisothermal crystallization process. Part 1: Thermal and structural characterization
Authors: Martinelli Andrea , Calì Massimo , D'Ilario Lucio , Francolini Iolanda , Piozzi Antonella 
Published: April 2011

AbstractThe effect of the holding temperature and time in the melt state of poly(L‐lactide) (PLLA) samples on the nonisothermal melt crystallization process and on the structure have been investigated by means of DSC, polarized optical microscopy and wide angle X‐ray scattering. As standard starting material, single crystals grown from dilute solution were used. In the mild melting condition, the survived athermal nuclei favor high temperature polymer crystallization, while the more severe treatment leads the PLLA to crystallize at higher supercooling with a sporadic nucleation. At the intermediate melting temperature a distinct double nucleation mechanism was observed while at the lower nuclei concentration, a double crystallization rate was also found. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Electrical conductivity of single walled and multiwalled carbon nanotube containing wool fibers
Authors: Montazer Majid , Ghayem Asghari Mohammad Samin , Pakdel Esfandiar 
Published: April 2011

AbstractThe main purpose of this study was producing conductive wool fabric applying carbon nanotubes. Raw and oxidized wool samples were treated with carbon nanotubes in the impregnating bath in the presence of citric acid as a crosslinking agent and sodium hypophosphite as a catalyst while sonicating them in the ultrasonic bath. Electrical resistance, washing durability, and color variation of treated samples were assessed. Through SEM images, the surface morphology of treated samples was studied confirming the surface coating through carbon nanotubes. According to the results, the electrical resistance of treated wool with carbon nanotubes reduced substantially. However, the single‐walled carbon nanotubes are more useful to increase the conductivity. In addition, the wool color changed into gray after the treatment. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Use of isothermal and nonisothermal chemiluminescence measurements for comparison of stabilizing efficiency of hydroxytyrosol (3,4‐dihydroxy‐phenylethanol), α‐tocopherol and irganox®1076 in polypropylene
Authors: Peltzer M. , Jiménez A. , Matisová‐Rychlá L. , Rychlý J. 
Published: April 2011

AbstractHydroxytyrosol (3,4‐dihydroxyphenylethanol) is a phenolic compound obtained during olive processing in oil manufacturing. It plays a role in enhancing the oxidative stability of olive oil with positive effects on human health. The raising interest towards the use of natural antioxidants as stabilizers in polymer formulations makes hydroxytyrosol a potential candidate to substitute synthetic antioxidants in polyolefin formulations. In this study, hydroxytyrosol was compared in antioxidant efficiency with two other compounds, one of them obtained from natural resources (α‐tocopherol) and a synthetic commercial phenolic antioxidant (Irganox®1076). Chemiluminescence was used to as a tool to assess the increase in the polypropylene stability to thermo‐oxidative degradation. A significant increase in the value of oxygen induction time with the initial concentration of natural antioxidants tested under isothermal conditions at 140, 150 and 160°C was observed. A comparison at the same concentration level (0.1 wt %) between the three antioxidants showed an order of stabilizing efficiency as: α‐tocopherol > Irganox®1076 > hydroxytyrosol, but all them showed clearly their stabilization performance in polypropylene. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation and characterization of high melt strength polypropylene with long chain branched structure by the reactive extrusion process
Authors: Cao Kun , Li Yan , Lu Zhan‐Quan , Wu Shui‐Liang , Chen Zhen‐Hua , Yao Zhen , Huang Zhi‐Ming 
Published: April 2011

AbstractThe reactive extrusion of maleic anhydride grafted polypropylene (PP‐g‐MAH) with ethylenediamine (EDA) as coupling agent is carried out in a corotating twin‐screw extruder to produce long chain branched polypropylene (LCBPP). Part of PP‐g‐MAH is replaced by maleic anhydride grafted high‐density polyethylene (HDPE‐g‐MAH) or linear low‐density polyethylene (LLDPE‐g‐MAH) to obtain hybrid long chain branched (LCB) polyolefins. Compared with the PP‐g‐MAH, PE‐g‐MAH, and their blends, the LCB polyolefins exhibit excellent dynamic shear and transient extensional rheological characteristics such as increased dynamic modulus, higher low‐frequency complex viscosity, broader relaxation spectra, significantly enhanced melt strength and strain‐hardening behaviors. The LCB polyolefins also have higher tensile strength, tensile modulus, impact strength and lower elongation at break than their blends. Furthermore, supercritical carbon dioxide (scCO2) is constructively introduced in the reactive extrusion process. In the presence of scCO2, the motor current of the twin extruder is decreased and LCB polyolefins with lower melt flow rate (MFR), higher complex viscosity and increased tensile strength and modulus can be obtained. This indicates that the application of scCO2 can reduce the viscosity of melt in extruder, enhance the diffusion of reactive species, and then facilitate the long chain branching reaction between anhydride group and primary amine group. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Sclerostin antibody treatment enhances bone strength but does not prevent growth retardation in young mice treated with dexamethasone
Authors: Marenzana M. , Greenslade K. , Eddleston A. , Okoye R. , Marshall D. , Moore A. , Robinson M. K. 
Published: April 2011

AbstractObjectiveExposure to supraphysiologic levels of glucocorticoid drugs is known to have detrimental effects on bone formation and linear growth. Patients with sclerosteosis lack the bone regulatory protein sclerostin, have excessive bone formation, and are typically above average in height. This study was undertaken to characterize the effects of a monoclonal antibody to sclerostin (Scl‐AbI) in mice exposed to dexamethasone (DEX).MethodsYoung mice were concomitantly treated with DEX (or vehicle control) and Scl‐AbI antibody (or isotype‐matched control antibody [Ctrl‐Ab]) in 2 independent studies. Linear growth, the volume and strength of the bones, and the levels of bone turnover markers were analyzed.ResultsIn DEX‐treated mice, Scl‐AbI had no significant effect on linear growth when compared to control treatment (Ctrl‐Ab). However, in mice treated with DEX and Scl‐ABI, a significant increase in trabecular bone at the femoral metaphysis (bone volume/total volume +117% versus Ctrl‐Ab–treated mice) and in the width and volume of the cortical bone at the femoral diaphysis (+24% and +20%, respectively, versus Ctrl‐Ab–treated mice) was noted. Scl‐AbI treatment also improved mechanical strength (as assessed by 4‐point bending studies) at the femoral diaphysis in DEX‐treated mice (maximum load +60% and ultimate strength +47% in Scl‐AbI–treated mice versus Ctrl‐Ab–treated mice). Elevated osteocalcin levels were not detected in DEX‐treated mice that received Scl‐AbI, although levels of type 5b tartrate‐resistant acid phosphatase were significantly lower than those observed in mice receiving DEX and Ctrl‐Ab.ConclusionScl‐AbI treatment does not prevent the detrimental effects of DEX on linear growth, but the antibody does increase both cortical and trabecular bone and improves bone mechanical properties in DEX‐treated mice.
Role of semaphorin 7a signaling in transforming growth factor β1–induced lung fibrosis and scleroderma‐related interstitial lung disease
Authors: Gan Ye , Reilkoff Ronald , Peng Xueyan , Russell Thomas , Chen Qingsheng , Mathai Susan K. , Homer Robert , Gulati Mridu , Siner Jonathan , Elias Jack , Bucala Richard , Herzog Erica 
Published: April 2011

AbstractObjectiveSemaphorin 7a regulates transforming growth factor β1 (TGFβ1)–induced fibrosis. This study was undertaken to test the hypothesis that semaphorin 7a exerts its profibrotic effects in part by promoting the tissue accumulation of CD45+ fibrocytes.MethodsA murine model of pulmonary fibrosis in which an inducible, bioactive form of the human TGFβ1 gene is overexpressed in the lung was used. Fibrosis and fibrocytes were evaluated in TGFβ1‐transgenic mice in which the semaphorin 7a locus had been disrupted. The effect of replacement or deletion of semaphorin 7a on bone marrow–derived cells was ascertained using bone marrow transplantation. The role of the semaphorin 7a receptor β1 integrin was assessed using neutralizing antibodies. The applicability of these findings to TGFβ1‐driven fibrosis in humans was examined in patients with scleroderma‐related interstitial lung disease (ILD).ResultsThe appearance of fibrocytes in the lungs of TGFβ1‐transgenic mice required semaphorin 7a. Replacement of semaphorin 7a on bone marrow–derived cells restored lung fibrosis and fibrocytes. Immunoneutralization of β1 integrin reduced pulmonary fibrocytes and fibrosis. Peripheral blood mononuclear cells (PBMCs) from patients with scleroderma‐related ILD showed increased levels of messenger RNA for semaphorin 7a and its receptors, with semaphorin 7a located on collagen‐producing fibrocytes and CD19+ lymphocytes. Peripheral blood fibrocyte outgrowth was enhanced in these patients. Stimulation of normal human PBMCs with recombinant semaphorin 7a enhanced fibrocyte differentiation; these effects were attenuated by β1 integrin neutralization.ConclusionOur findings indicate that interventions that reduce semaphorin 7a expression or prevent the semaphorin 7a–β1 integrin interaction may ameliorate TGFβ1‐driven or fibrocyte‐associated autoimmune fibroses.
Dose escalation of certolizumab pegol from 200 mg to 400 mg every other week provides no additional efficacy in rheumatoid arthritis: An analysis of individual patient‐level data
Authors: Curtis Jeffrey R. , Chen L. , Luijtens K. , Navarro‐Millan I. , Goel N. , Gervitz L. , Weinblatt M. 
Published: April 2011

AbstractObjectiveTo determine whether certolizumab pegol (CZP) dosage escalation from 200 mg to 400 mg every other week benefits some patients with rheumatoid arthritis (RA).MethodsIn the extension of the Rheumatoid Arthritis Prevention of Structural Damage 1 (RAPID 1) study into an open‐label study, all patients received CZP 400 mg every other week in combination with methotrexate (MTX). Before the open‐label phase of the study, patients had received CZP 200 mg or 400 mg every other week, or placebo every other week, as add‐on therapy to MTX. The open‐label study included those who had completed the RAPID 1 study (to week 52) and also those who had been withdrawn from the study (at week 16, due to inadequate response). At 12 weeks and 48 weeks after enrollment in the open‐label study, changes in the Disease Activity Score in 28 joints (DAS28) were compared in dose‐escalation patients (200 mg increased to 400 mg every other week) versus stable‐dosage patients (400 mg every other week), using cumulative probability plots of individual patient‐level data.ResultsIn the group of patients who had completed the RAPID 1 study and had moderate or severe disease activity at entry into the open‐label study, and in those who had been withdrawn early from the RAPID 1 study, the median DAS28 improvements 12 weeks after enrollment into the open‐label study were similar in the dose‐escalation and stable‐dose groups. Individual patient‐level data revealed no greater likelihood of response in the group of patients who received an increased dosage of CZP versus those in whom a stable dosage was maintained, whether they had completed the RAPID 1 study or had been withdrawn early.ConclusionAlthough patient heterogeneity in clinical settings is acknowledged, the present results indicate that increasing the dose of CZP from 200 mg to 400 mg offers little additional benefit in RA, even for selected patients.
Oral administration of artemisinin analog SM934 ameliorates lupus syndromes in MRL/lpr mice by inhibiting Th1 and Th17 cell responses
Authors: Hou Li‐Fei , He Shi‐Jun , Li Xin , Yang Yang , He Pei‐Lan , Zhou Yu , Zhu Feng‐Hua , Yang Yi‐Fu , Li Ying , Tang Wei , Zuo Jian‐Ping 
Published: April 2011

AbstractObjectiveSM934, an artemisinin derivative, possesses potent antiproliferative and antiinflammatory properties. The aim of this study was to examine the effects and explore the mechanisms of SM934 to treat autoimmune disease in lupus‐prone female MRL/lpr mice.MethodsIn vitro, the effects of SM934 on the activation of polyclonal CD4+ T cells and the differentiation of naive CD4+ T cells were examined. In vivo, the preventative or therapeutic effects of SM934 in MRL/lpr mice were investigated. Ex vivo, the mechanisms of treatment were explored according to the immunologic correlates of disease.ResultsIn vitro, SM934 inhibited interferon‐γ (IFNγ) and interleukin‐17 (IL‐17) production from polyclonal CD4+ T cells activated by T cell receptor engagement and the differentiation of naive CD4+ T cells into Th1 and Th17 cells, but not Treg cells. In vivo, 12‐week‐old MRL/lpr mice treated with SM934 for 4 weeks showed significantly ameliorated proteinuria and renal lesion severity; decreased levels of blood urea nitrogen, serum IFNγ, and serum anti–double‐stranded DNA antibodies; decreased spleen size; and a lower percentage of CD3+B220+CD4−CD8− T cells; 16‐week‐old MRL/lpr mice treated with SM934 for 8 weeks avoided severe proteinuria and survived longer. Ex vivo, SM934 treatment elevated the percentage of Treg cells, inhibited the development of Th1 and Th17 cells, and impeded the comprehensive activation of STAT‐1, STAT‐3, and STAT‐5 proteins in splenocytes.ConclusionTaken together, the results of this study demonstrated that the artemisinin analog SM934 had therapeutic effects in lupus‐prone female MRL/lpr mice by inhibiting both Th1 cell and Th17 cell responses. Moreover, this study indicated that both IFNγ and IL‐17 are required for the elicitation and development of murine lupus.
Solid malignancies among etanercept‐treated patients with granulomatosis with polyangiitis (Wegener's): Long‐term followup of a multicenter longitudinal cohort
Authors: Silva Francisco , Seo Philip , Schroeder Darrell R. , Stone John H. , Merkel Peter A. , Hoffman Gary S. , Spiera Robert , Sebastian Jodi K. , Davis John C. , St.Clair E. William , Allen Nancy B. , McCune W. Joseph , Ytterberg Steven R. , Specks Ulrich ,   Wegener's Granulomatosis Etanercept Trial Research Group
Published: April 2011

AbstractObjectiveAn association between therapeutic inhibition of tumor necrosis factor (TNF) and solid malignancies was observed during the Wegener's Granulomatosis Etanercept Trial (WGET), which included 180 patients with granulomatosis with polyangiitis (Wegener's) (GPA). The present study was conducted to determine the malignancy risk beyond the time of exposure to study therapy.MethodsThe occurrence and type of solid malignancies were ascertained using a standardized data form. Data collected included vital status, histologic findings, and therapeutic interventions. The Surveillance, Epidemiology, and End‐Results database was used to estimate a standardized incidence rate (SIR) for solid malignancies.ResultsPost‐trial followup data were available for 153 patients (85% of the original cohort), with a median followup time of 43 months. Fifty percent of these patients had received etanercept. There were no differences in demographic characteristics between the etanercept and placebo groups. Thirteen new solid malignancies were detected, 8 in the etanercept group and 5 in the placebo group. Compared to the general population, the risk of solid malignancies in the etanercept group was increased (SIR 3.92 [95% confidence interval 1.69–7.72]), but was not different from the risk in the placebo group compared to the general population (SIR 2.89 [95% confidence interval 0.94–6.73]). All solid malignancies occurred in patients who had been exposed to cyclophosphamide. The overall duration of disease and a history of malignancy before trial enrollment were associated with the development of malignancy during post‐trial followup.ConclusionThe incidence of solid malignancy remained increased during long‐term followup of the WGET cohort. However, this could not be attributed solely to etanercept exposure during the trial. Anti‐TNF therapy with etanercept appears to further increase the risk of malignancy observed in patients with GPA treated with cytotoxic agents and should be avoided in these patients.