bluuebunny/crossref_metadata_2025_split huggingface dataset:
A p53 Axis Regulates B Cell Receptor-Triggered, Innate Immune System-Driven B Cell Clonal Expansion
Authors: Lee Hyunjoo , Haque Shabirul , Nieto Jennifer , Trott Joshua , Inman John K. , McCormick Steven , Chiorazzi Nicholas , Mongini Patricia K. A. 
Published: May 2012

Abstract
Resting mature human B cells undergo a dynamic process of clonal expansion, followed by clonal contraction, during an in vitro response to surrogate C3d-coated Ag and innate immune system cytokines, IL-4 and BAFF. In this study, we explore the mechanism for clonal contraction through following the time- and division-influenced expression of several pro- and anti-apoptotic proteins within CFSE-labeled cultures. Several findings, involving both human and mouse B cells, show that a mitochondria-dependent apoptotic pathway involving p53 contributes to the high activation-induced cell death (AICD) susceptibility of replicating blasts. Activated B cell clones exhibit elevated p53 protein and elevated mRNA/protein of proapoptotic molecules known to be under direct p53 transcriptional control, Bax, Bad, Puma, Bid, and procaspase 6, accompanied by reduced anti-apoptotic Bcl-2. Under these conditions, Bim levels were not increased. The finding that full-length Bid protein significantly declines in AICD-susceptible replicating blasts, whereas Bid mRNA does not, suggests that Bid is actively cleaved to short-lived, proapoptotic truncated Bid. AICD was diminished, albeit not eliminated, by p53 small interfering RNA transfection, genetic deletion of p53, or Bcl-2 overexpression. DNA damage is a likely trigger for p53-dependent AICD because susceptible lymphoblasts expressed significantly elevated levels of both phosphorylated ataxia telangiectasia mutated-Ser1980 and phospho-H2AX-Ser139. Deficiency in activation-induced cytosine deaminase diminishes but does not ablate murine B cell AICD, indicating that activation-induced cytosine deaminase-induced DNA damage is only in part responsible. Evidence for p53-influenced AICD during this route of T cell-independent clonal expansion raises the possibility that progeny bearing p53 mutations might undergo positive selection in peripherally inflamed tissues with elevated levels of IL-4 and BAFF.
Signal-Transducing Adaptor Protein-2 Modulates Fas-Mediated T Cell Apoptosis by Interacting with Caspase-8
Authors: Sekine Yuichi , Yamamoto Chikako , Kakisaka Michinori , Muromoto Ryuta , Kon Shigeyuki , Ashitomi Dai , Fujita Natsuko , Yoshimura Akihiko , Oritani Kenji , Matsuda Tadashi 
Published: May 2012

Abstract
We found that an adaptor protein, signal-transducing adaptor protein (STAP)-2, is a new member of the Fas–death-inducing signaling complex and participates in activation-induced cell death in T cells. STAP-2 enhanced Fas-mediated apoptosis and caspase-8 aggregation and activation in Jurkat T cells. Importantly, STAP-2 directly interacted with caspase-8 and Fas, resulting in enhanced interactions between caspase-8 and FADD in the Fas–death-inducing signaling complex. Moreover, STAP-2 protein has a consensus caspase-8 cleavage sequence, VEAD, in its C-terminal domain, and processing of STAP-2 by caspase-8 was crucial for Fas-induced apoptosis. Physiologic roles of STAP-2 were confirmed by observations that STAP-2–deficient mice displayed impaired activation-induced cell death and superantigen-induced T cell depletion. Therefore, STAP-2 is a novel participant in the regulation of T cell apoptosis after stimulation.
Scanning Electrochemical Microscopy
Authors: Amemiya Shigeru 
Published: May 2012

AbstractIn this article, we introduce the principle of scanning electrochemical microscopy (SECM) and its applications as a powerful electrochemical method for material characterization. The principle of SECM is based on the use of a micrometer‐ or nanometer‐sized ultramicroelectrode as the scanning chemical probe of electrons, ions, and molecules that are transferred across the interface between a target solid material and an electrolyte solution as well as air/liquid and liquid/liquid interfaces and membranes. In comparison to traditional electrochemical methods, SECM is much higher in spatial resolution and mass transport to find its advantages in the chemical imaging of a heterogeneously reactive material surface and the quantitative study of interfacial reaction dynamics. The unique capability of imaging an interfacial reactivity renders SECM complementary to other scanning probe microscopy techniques and also combinable with them to yield multidimensional images of the material surface. In this article, various operation modes of SECM are introduced and followed by examples of practical measurements based on imaging, approach curve, voltammetry, and amperometry. Present limits of the technique in both theory and experiment are briefly discussed. In addition, numerical and analytical approaches to data analysis as well as experimental protocols for tip fabrication and characterization are described.
Low‐Field Magnetoresistance in La0.67Sr0.33MnO3:ZnO Composite Film
Authors: Staruch Margo , Gao Haiyong , Gao Pu‐Xian , Jain Menka 
Published: May 2012

AbstractA nanocomposite film of La0.67Sr0.33MnO3 (LSMO):ZnO is synthesized by depositing LSMO solution on a vertical array of ZnO nanorods grown on (0001) Al2O3 substrate. The magnetic behavior of the composite film differs from that of a pure LSMO film, possibly due to smaller grain size in the composite, small amount of Zn doping, or the presence of nonmagnetic ZnO phase near the LSMO grain boundaries. Magnetotransport measurements show that the low‐field magnetoresistance (LFMR) of the nanocomposite film is significantly enhanced as compared to that observed for pure LSMO film. The highest value of the LFMR of the nanocomposite film at 10 K is –23.9% with a magnetic field of 0.5 T applied parallel to the current.
Three Dimensional PtRh Alloy Porous Nanostructures: Tuning the Atomic Composition and Controlling the Morphology for the Application of Direct Methanol Fuel Cells
Authors: Zhang Yuan , Janyasupab Metini , Liu Chen‐Wei , Li Xinxin , Xu Jiaqiang , Liu Chung‐Chiun 
Published: May 2012

AbstractA strategy for the synthesis of PtRh alloy 3D porous nanostructures by controlled aggregation of nanoparticles in oleylamine is presented. The atomic ratio between the two components (Pt and Rh) is tuned by varying the concentration of precursor salts accommodating the oxidation of methanol. The morphology of PtRh alloy nanostructure is controlled by elevating the temperature of the reaction system to 240 °C. The prepared 3D porous nanostructures provide a high degree of electrochemical activity and good durability toward the methanol oxidation reaction compared to those of the commercial Pt/C (E‐TEK) and PtRh nanoparticles. Therefore, the 3D alloy porous nanostructures provide a good opportunity to explore their catalytic properties for methanol oxidation.
The brain‐derived neurotrophic‐factor (BDNF) val66met polymorphism is associated with geriatric depression: A meta‐analysis
Authors: Pei Yu , Smith Alicia K. , Wang Yongjun , Pan Yanli , Yang Jian , Chen Qi , Pan Weigang , Bao Feng , Zhao Lisha , Tie Changle , Wang Yizheng , Wang Jian , Zhen Wenfeng , Zhou Jinxia , Ma Xin 
Published: May 2012

AbstractDepression has been associated with reduced expression of brain‐derived neurotrophic factor (BDNF) in the hippocampus. Genetic association studies of theBDNFVal66Met polymorphism (rs6265) in geriatric depression have produced inconsistent results. A meta‐analysis of studies was conducted to compare the frequency of theBDNFVal66Met variant between cases with geriatric depression and age‐matched controls. A total of five studies involving 523 cases with geriatric depression and 1,220 psychiatrically healthy controls was included. Met allele carriers had an increased risk for geriatric depression when compared to Val/Val homozygotes (P = 0.004, OR = 1.48, 95% CI = 1.13–1.93). Our findings suggest theBDNFMet allele may confer increased risk for depression as individual age. © 2012 Wiley Periodicals, Inc.
Modification of polypropylene via the free‐radical grafting ternary monomer in water suspension systems
Authors: Zhu Baodong , Dong Weichao , Wang Jian , Song Jun , Dong Qun 
Published: May 2012

AbstractMaleic anhydride, styrene, and butyl acrylate were grafted onto polypropylene (PP) via free‐radical polymerization. The grafted product, polypropylene‐g‐(maleic anhydride–styrene–butyl acrylate) (PP‐g‐PMSB), was prepared in a water suspension system, and a nongrafted polymer, poly(maleic anhydride–styrene–butyl acrylate) (PMSB′), was produced at the same time. The optimal synthesis conditions were determined by orthogonal experiments. The crystallinity, thermal stability, melt flow rate, and hydrophilicity of the grafting samples were investigated in the presence or absence of PMSB′. The results indicate that the grafting percentage (Gp) of PP‐g‐PMSB and the content of PMSB′ (Cm) increased as the monomer content increased under the optimum reaction conditions. All of these ternary monomers were grafted onto the PP backbone as long‐chain branches. With increasing Gp, PP‐g‐PMSB's polarity and thermal stability increased, the crystallinity decreased, and the molecular distribution became narrower. The contact angle decreased to 72.12° when Gp was 6.87%. With increasing Cm, the crystallinity and thermal stability of the grafting products decreased compared to PP‐g‐PMSB and the molecular distribution grew wider. The contact angle decreased to 63.51° when Cm was 3.64%; this indicated that the presence of PMSB′ further improved the hydrophilicity of the grafted products. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Influence of binary combined systems of antioxidants on the stabilization of peroxide‐cured low‐density polyethylene
Authors: Zhang Xiaohu , Yang Hongmei , Song Yihu , Zheng Qiang 
Published: May 2012

AbstractThe secondary antioxidants Irganox 168 and 242 and dilaurylthiodipropionate (didodecyl‐3,3′‐thiodipropionate) (DLTP) were chosen to be combined with the primary phenol antioxidants Irganox 300, 1010, 1035, and 1076, and the effects of the binary combined systems of antioxidants on the peroxide curing reaction and the long‐term stability of crosslinked low‐density polyethylene (XLPE) were studied through isothermal dynamic rheological and mechanical testing. The results show that the primary phenol antioxidants with lower melting points had better resistance to scorching and exhibited good synergistic effects with the secondary antioxidants. Irganox 168 had little resistance to scorching, whereas Irganox DLTP had moderate resistance, and Irganox 242 had the greatest resistance. Irganox 168 and DLTP guaranteed the mechanical properties well, whereas Irganox 242 reduced the tensile strength obviously. Irganox 300 and 1035 combined with secondary antioxidants performed poorly in long‐term thermal aging test, whereas Irganox 1076 in combination with secondary antioxidants displayed a moderate effect of aging resistance, and Irganox 1010 showed the best effect. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2012
Preparation and characterization of grafting polyacrylamide from PET films by SI‐ATRP via water‐borne system
Authors: Zhang Hongwen , Du Zhenyu , Jiang Yan , Yu Qiang 
Published: May 2012

AbstractThe grafted homopolymer and comb‐shaped copolymer of polyacrylamide were prepared by combining the self‐assembly of initiator and water‐borne surface‐initiated atom transfer radical polymerization (SI‐ATRP). The structures, composition, properties, and surface morphology of the modified PET films were characterized by FTIR/ATR, X‐ray photoelectron spectroscopy (XPS), contact angle measurement, and scanning electronic microscopy (SEM). The results show that the surface of PET films was covered by equable grafting polymer layer after grafted polyacrylamide (PAM). The amount of grafting polymer increased linearly with the polymerization time added. The GPC date show that the polymerization in the water‐borne medium at lower temperature (50°C) shows better “living” and control. After modified by comb‐shaped copolymer brushes, the modified PET film was completely covered with the second polymer layer (PAM) and water contact angle decreased to 13.6°. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Bis(N‐benzyl piperazino) thiuram disulfide and dibenzothiazyl disulfide as synergistic safe accelerators in the vulcanization of natural rubber
Authors: Alam Md. Najib , Mandal Swapan Kumar , Debnath Subhas Chandra 
Published: May 2012

AbstractSome investigation regarding the effect of binary system of accelerators comprising one safe thiuram disulfide, namely bis(N‐benzyl piperazino) thiuram disulfide (BPTD) and dibenzothiazyl disulfide (MBTS), on the vulcanization of NR is carried out. The results are compared with those obtained with conventional tetra methyl thiuram disulfide (TMTD) presently considered as unsafe. The vulcanizates obtained from safe synergistic pair of accelerators (BPTD‐MBTS) possess comparable mechanical properties [modulus, tensile strength, and elongation at break (%)] and exhibits some improvement in heat resistant behavior when compared with those obtained with TMTD‐MBTS system. In the light of mechanical properties, safe BPTD‐MBTS system introduces the safe noncarcinogenic rubber accelerator in the vulcanization of rubber. Same type of synergistic activity may be due to comparable activation energy for both the TDs with the combination of MBTS. Although rate constant values are low for BPTD‐MBTS (6 : 3) compared to TMTD‐MBTS (6 : 3) in the high temperature vulcanization, the crosslinking efficiency of former is very large compared to later. This may be responsible for improvement in heat resistance behavior of the novel accelerator in the combination with MBTS. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Grafting polymer brushes on graphene oxide for controlling surface charge states and templated synthesis of metal nanoparticles
Authors: Gao Tingting , Ye Qian , Pei Xiaowei , Xia Yanqiu , Zhou Feng 
Published: May 2012

AbstractIn this article, poly[(dimethylamino)ethyl methacrylate] (PDMAEMA) brushes were grafted onto graphene oxide (GO) sheet via noncovalent modification of pyrene terminated initiator and subsequent in situ surface‐initiated atom transfer radical polymerization (SI‐ATRP). The results of zeta‐potentials, dispersivity measurement as well as the permeability of cationic and anionic redox‐active probe molecules reveal that the as‐prepared GO/PDMAEMA composite exhibits zwitterionicity because of the presence of phenol hydroxyl, carboxyl, and amine groups and the charging state can be manipulated by controlling pH values. Furthermore, by ion exchange and in situ reduction, palladium and gold nanoparticles were successfully uploaded and the catalytic property of the uniformly distributed Pd‐Au nanoparticles on GO sheet was investigated. These results reported in this work may open primarily toward constructing a bridge among GO, charged polymer and metal nanoparticles and secondarily to represent a new strategy for uniformly depositing inorganic nanoparticles. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Fatigue and hysteresis behavior of halloysite nanotubes‐filled natural rubber (SMR L and ENR 50) nanocomposites
Authors: Ismail H. , Salleh S. Z. , Ahmad Z. 
Published: May 2012

AbstractThe effect of various halloysite nanotubes (HNTs) loading on fatigue life, stress–strain behavior, and hysteresis of HNTs/Standard Malaysian Rubber (SMR) L and HNTs/epoxidized natural rubber (ENR) 50 nanocomposites were studied. The addition of HNTs caused decrement in fatigue life for both nanocomposites at any extension ratio. Generally, HNTs/SMR L nanocomposites showed higher fatigue life than ENR 50 nanocomposites. Addition of more HNTs caused decrement of stress for HNTs/SMR L nanocomposites, whereas HNTs/ENR 50 nanocomposites showed vice versa at any strain. This result was supported by the graph of accumulated strain energy against extension ratio. Hysteresis values increased with addition of HNTs in both nanocomposites where of HNTs/ENR 50 nanocomposites exhibited higher hysteresis than HNTs/SMR L nanocomposites at any HNTs loading. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Ultra‐violet curable resin based on palm oil: Determination of reaction condition and characterization of the resin
Authors: Rozman H. D. , Tai N. L. , Tay G. S. 
Published: May 2012

AbstractIn this study, a UV curable resin based on palm oil was prepared by modifying palm oil with glycerol and glycidyl methacrylate (GMA). First, monoglyceride (MG) was prepared from a mixture of palm oil and glycerol at a ratio of 1 : 2 based on equivalent basis. The MG was treated with GMA to introduce unsaturated groups to MG chain via etherification between epoxy group (from GMA) and hydroxyl group (from MG). The amount of catalyst needed, reaction temperature, and time for this chemical modification were determined. The completion of reaction between GMA and monoglyceride was measured using Fourier transform infrared (FTIR) spectroscopy by monitoring the disappearance of the epoxy group in FTIR spectrum. An increment at peak 1630 cm−1 in FTIR spectrum was observed when more GMA was used in the chemical modification. Viscosity test and gel permeation chromatography analysis were carried out to characterize the resin produced. The resin was then cured using UV radiation and the properties of the cured resin were measured. From the results, the gel content of the cured resin was more than 97%. The hardness of the MG‐GMA film was influenced by the amount of GMA used. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation and characterization of graphene oxide/poly(vinyl alcohol) composite nanofibers via electrospinning
Authors: Wang Chen , Li Yadong , Ding Guqiao , Xie Xiaoming , Jiang Mianheng 
Published: May 2012

AbstractGraphene oxide (GO) was well dispersed in poly(vinyl alcohol) (PVA) diluted aqueous solution, and then the mixture was electrospun into GO/PVA composite nanofibers. Electron microscopy and Raman spectroscopy on the as‐prepared and calcined samples confirm the uniform distribution of GO sheets in the nanofibers. The thermal and mechanical properties of the nanofibers vary considerably with different GO filler contents. The decomposition temperatures of the GO/PVA composite nanofiber dropped by 38–50°C compared with pure PVA. A very small loading of 0.02 wt % GO increases the tensile strength of the nanofibers by 42 times. A porous 3D structure was realized by postcalcining nanofibers in H2. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Bond properties of structural polypropylene fiber in hybrid nonstructural polypropylene and structural polypropylene fiber‐reinforced latex‐modified cement‐based composites
Authors: Jung Ji‐Youn , Park Chan‐Gi , Park Jong‐Sik 
Published: May 2012

AbstractThis study investigated the effect of styrene–butadiene latex (latex) content on the pullout behavior of structural polypropylene fibers (SPF) in hybrid fiber‐reinforced latex‐modified cement‐based composite made with a blend of SPF and nonstructural polypropylene fiber. Bond tests were performed in accordance with JCI SF‐8. NSPF was incorporated at 9.10 kg/m3 and SPF at 0.45 kg/m3. Latex was added at 0–20% of the binder weight. The experimental results demonstrated that latex improved the pullout properties of the load–displacement curve in the debonded zone. Also, the bond strength and interface toughness increased with latex content up to 15% but decreased when the latex content reached 20%. Microstructure analysis showed increased scratching on the SPF surface. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis, characterization, and thermal properties of alkyl‐functional naphthoxazines
Authors: Uyar Tamer , Hacaloglu Jale , Ishida Hatsuo 
Published: May 2012

AbstractA series of alkyl‐functional naphthoxazine resins having various alkyl chain lengths from C1 to C18 are synthesized with a high yield and high purity by the reactions of 1,5‐dihydroxynaphthalene, formaldehyde, and aliphatic amines. The proposed chemical structures of the naphthoxazines are confirmed by high‐resolution mass spectrometry, 1H nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and pyrolysis mass spectrometry studies. The alkyl‐functional naphthoxazines have shown low polymerization temperature characteristics where polymerization of these monomers is achieved in the range of 150–170°C yielding cross‐linked polynaphthoxazines. The low‐temperature polymerization characteristics and the associated thermal degradation behaviors are studied. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Free‐radical grafting of trans‐ethylene‐1,2‐dicarboxylic acid onto molten ethylene‐vinyl acetate copolymer
Authors: Krivoguz Yuri M. , Guliyev Abasgulu M. , Pesetskii Stepan S. 
Published: May 2012

AbstractDistinctive features of free‐radical grafting of trans‐ethylene‐1,2‐dicarboxylic acid (TEDA) onto macromolecules of molten ethylene‐vinyl acetate copolymer (EVA) in the course of reactive extrusion have been investigated along with structure, mechanical characteristics, and high‐elastic properties of molten functionalized products (EVA‐g‐TEDA). It is shown that EVA‐g‐TEDA yield depends on both the peroxide initiator concentration and content of vinyl acetate units in the copolymer molecular structure. At functionalization, acid grafting is accompanied by secondary reactions of macromolecular degradation and crosslinking. With a low‐peroxide initiator concentration (0.1 wt %), degradation prevails; with a higher (0.3 wt %) concentration, crosslinking of macromolecules prevails. It is reported that monomers being grafted attach mostly over secondary carbon atoms in the polymer chain. EVA‐g‐TEDA appears to have a less perfect crystal structure with a lower‐melting temperature and crystallinity as against the starting polymer. The functionalized products display enhanced rigidity and lower deformability in comparison with the initial copolymer. Variations in the swelling ratio and melt strength of EVA‐g‐TEDA depend on the course of competing secondary processes of macromolecular degradation and crosslinking. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Polyaniline–TiO2 hybrid‐coated cotton fabric for durable electrical conductivity
Authors: Savitha K. U. , Prabu H. Gurumallesh 
Published: May 2012

AbstractA polyaniline–TiO2 hybrid was coated on cotton fabric to make it electrically conductive. A One‐pot method of synthesis with acetic acid medium was used, in which TiCl4 was used as precursor. The oxidative polymerization of aniline adsorbed on TiO2 (anatase form) was performed in the presence of cotton fabric. Fabric crystallinity was least affected by the coatings, as confirmed by XRD analysis. FTIR studies revealed interactions between fiber and hybrid. The morphological study through SEM showed the uniform coating of hybrid over the fibers of the cotton fabric and AFM analysis revealed the rod‐like structure of the hybrid. The strength of the coated fabrics was assessed using abrasion tests. The electrical conductivity was determined using electrochemical impedance spectroscopy (EIS).The conductivity value varied with respect toTiO2 content and ranged in the order 10−4 to 102S/cm. The effect of atmospheric aging was assessed. A more durable conductivity was observed in hybrid‐coated fabric than pristine polyaniline‐coated fabric. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013