bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thin shell analysis from scattered points with maximum‐entropy approximants
Authors: Millán D. , Rosolen A. , Arroyo M. 
Published: September 2010

AbstractWe present a method to process embedded smooth manifolds using sets of points alone. This method avoids any global parameterization and hence is applicable to surfaces of any genus. It combines three ingredients: (1) the automatic detection of the local geometric structure of the manifold by statistical learning methods; (2) the local parameterization of the surface using smooth meshfree (here maximum‐entropy) approximants; and (3) patching together the local representations by means of a partition of unity. Mesh‐based methods can deal with surfaces of complex topology, since they rely on the element‐level parameterizations, but cannot handle high‐dimensional manifolds, whereas previous meshfree methods for thin shells consider a global parametric domain, which seriously limits the kinds of surfaces that can be treated. We present the implementation of the method in the context of Kirchhoff–Love shells, but it is applicable to other calculations on manifolds in any dimension. With the smooth approximants, this fourth‐order partial differential equation is treated directly. We show the good performance of the method on the basis of the classical obstacle course. Additional calculations exemplify the flexibility of the proposed approach in treating surfaces of complex topology and geometry. Copyright © 2010 John Wiley & Sons, Ltd.
Proteomic and PROTEOMEX profiling of mammary cancer progression in a HER‐2/neu oncogene‐driven animal model system
Authors: Croci Stefania , Recktenwald Christian V. , Lichtenfels Rudolf , Nicoletti Giordano , Dressler Sven P. , De Giovanni Carla , Astolfi Annalisa , Palladini Arianna , Shin‐ya Kazuo , Landuzzi Lorena , Nanni Patrizia , Lollini Pier‐Luigi , Seliger Barbara 
Published: September 2010

AbstractThe prevention of mammary carcinoma by immunological strategies targeting the HER‐2/neu receptor has proved to be effective in preclinical models. Thus, a well‐characterized HER‐2/neu oncogene‐driven mammary carcinogenesis model was analysed by various profiling strategies following “triplex” vaccination to identify new candidate targets for breast cancer immunoprevention. 2‐DE‐based proteomic profiling of preneoplastic and tumour lesions versus normal and aged mammary tissue demonstrated that tumour progression was associated with an up‐regulation of molecular chaperones including glucose‐regulated protein (GRP)78 and of proteins favouring cell motility, which was in line with the corresponding transcriptomic profiling data. Furthermore, PROTEOMEX analyses suggested that naturally induced autoantibody responses occur during early phases of mammary cancer progression. Most of the cancer progression‐induced antibodies targeted proteins of normal and preneoplastic mammary glands. However, three proteins were only recognized by sera obtained from vaccinated mice, including 2 isoforms of annexin A6. The distinct expression patterns for annexin A6 and GRP78 during tumour progression were further verified by western blot and/or immunoprecipitation. In addition, an inhibitor‐mediated blockade of GRP78 expression in a model cell line caused a reduced cell growth. Thus, the proteome‐based approaches applied in the murine BALB‐NeuT model might indeed provide candidates for immunoprevention strategies in breast cancer.
Pseudo‐neutral‐loss scan for selective detection of phosphopeptides and N‐glycopeptides using liquid chromatography coupled with a hybrid linear ion‐trap/orbitrap mass spectrometer
Authors: Hsiao He‐Hsuan , Urlaub Henning 
Published: September 2010

AbstractWe describe a novel method, termed “pseudo‐neutral‐loss scan” MS, for selectively probing phosphopeptides and glycopeptides on a LTQ‐Orbitrap mass spectrometer. The instrument has been programmed such that an in‐source CID energy is applied to all species that eluted from LC column and were subsequently ionised in the electrospray ion source. Ion pairs that differ in the mass of a neutral loss of phosphoric acid or monosaccharide residues are automatically selected for CID MS/MS and further for multi‐stage‐activation MS3. Our method should prove useful for a highly selective and sensitive approach to identify phosphopeptides and glycopeptides from purified protein digestion without any further enrichment, and could potentially be of use in more complex mixture.
Proteomic characterization of Her2/neu‐overexpressing breast cancer cells
Authors: Chen Hexin , Pimienta Genaro , Gu Yiben , Sun Xu , Hu Jianjun , Kim Min‐Sik , Chaerkady Raghothama , Gucek Marjan , Cole Robert N. , Sukumar Saraswati , Pandey Akhilesh 
Published: September 2010

AbstractThe receptor tyrosine kinase HER2 is an oncogene amplified in invasive breast cancer and its overexpression in mammary epithelial cell lines is a strong determinant of a tumorigenic phenotype. Accordingly, HER2‐overexpressing mammary tumors are commonly indicative of a poor prognosis in patients. Several quantitative proteomic studies have employed two‐dimensional gel electrophoresis in combination with MS/MS, which provides only limited information about the molecular mechanisms underlying HER2/neu signaling. In the present study, we used a SILAC‐based approach to compare the proteomic profile of normal breast epithelial cells with that of Her2/neu‐overexpressing mammary epithelial cells, isolated from primary mammary tumors arising in mouse mammary tumor virus‐Her2/neu transgenic mice. We identified 23 proteins with relevant annotated functions in breast cancer, showing a substantial differential expression. This included overexpression of creatine kinase, retinol‐binding protein 1, thymosin 4 and tumor protein D52, which correlated with the tumorigenic phenotype of Her2‐overexpressing cells. The differential expression pattern of two genes, gelsolin and retinol binding protein 1, was further validated in normal and tumor tissues. Finally, an in silico analysis of published cancer microarray data sets revealed a 23‐gene signature, which can be used to predict the probability of metastasis‐free survival in breast cancer patients.
Covalent bonded polymer–graphene nanocomposites
Authors: Pramoda K. P. , Hussain H. , Koh H.M. , Tan H. R. , He C. B. 
Published: September 2010

AbstractThis report describes a new route to covalently bonded polymer–graphene nanocomposites and the subsequent enhancement in thermal and mechanical properties of the resultant nanocomposites. At first, the graphite is oxidized by the modified Hummers method followed by functionalization with Octadecylamine (ODA). The ODA functionalized graphite oxides are reacted with methacryloyl chloride to incorporate polymerizable CC functionality at the nanographene platelet surfaces, which were subsequently employed in in situ polymerization of methylmethacrylate to obtain covalently bonded poly(methyl methacrylate) (PMMA)–graphene nanocomposites. The obtained nanocomposites show significant enhancement in thermal and mechanical properties compared with neat PMMA. Thus, even with 0.5 wt % graphene nanosheets, the Tg increased from 119 °C for neat PMMA to 131 °C for PMMA–graphene nanocomposite, and the respective storage modulus increased from 1.29 to 2 GPa. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4262–4267, 2010
Hard nanocomposite comprising stereoregular syndiotactic polypropylene with chemically bonded gold nanoparticles
Authors: Yeh Jie‐Ru , Tseng Fu‐Yuan , Yeh Je‐Yuan , Tsai Jing‐Cherng , Tsiang Raymond Chien‐Chao 
Published: September 2010

AbstractAn effective method to synthesize directly a hard composite material containing uniformly dispersed nanogold particles chemically bonded with a stereospecific, crystalline polymer matrix has been developed. Syndiotactic polypropylene was synthesized and functionalized to have a hydroxyl terminal group (sPPOH) via a metallocene catalysis with a selective chain transfer. Next, sPPOH was activated to react with ethylene sulfide forming the thiol‐terminated polymer, sPPSH. sPPSH was then chemically bonded to gold nanoparticles (AuNPs) formed in situ via a reduction of HAuCl4. The bonding between thiol and AuNP stabilized the AuNPs and led to the formation of sPPAuNPs composite containing uniformly‐dispersed AuNPs of a 19–40 nm size without noticeable aggregation. Furthermore, the chemical bonding of AuNPs has afforded sPPAuNPs a thermal degradation temperature (TD) 49.4 °C higher than the pristine sPP or sPPOH and 25.7 °C higher than sPPSH without any adverse effect on the crystalline temperature and melting temperature. In addition, the characteristic UV‐Vis absorption wavelength of sPPAuNPs remains the same at various temperatures, thus indicating the independence of optical property on temperature as well as the good thermal stability of the sPPAuNPs composite. 1H NMR, 13C NMR, FESEM, STEM, XPS, TGA and DSC were used to investigate the molecular structure, morphology and thermal properties of the resulting sPPAuNPs nanocomposite. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
The influence of solution‐state conditions and stirring rate on the assembly of poly(acrylic acid)‐containing amphiphilic triblock copolymers with multi‐amines
Authors: Sorrells Jennifer L. , Tsai Ying‐Hsin , Wooley Karen L. 
Published: September 2010

AbstractIn the effort towards making nanoscale objects and assemblies feasible for use as functional materials, it is imperative to obtain control over the fundamental architectures and essential to understand what experimental conditions cause the manifestation of specific morphologies. A number of factors are known to influence the shape during the self‐assembly of amphiphilic block copolymers in solution, including solvent composition, polymer length, hydrophobicity versus hydrophilicity, as well as the addition of additives that can interact with segments of the block copolymers. This research, focused on developing an understanding of the micellar architectures accessed by the amphiphilic triblock copolymer of acrylic acid, methyl acrylate, and styrene, PAA85‐b‐PMA40‐b‐PS35, as a function of the stirring rate, together with other factors, when undergoing coassembly with ethylenediamine or diethylenetriamine in water/tetrahydrofuran solutions. The work demonstrates that the rate at which the polymer solution was stirred impacts the shape of the solution‐state assemblies formed by the triblock copolymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Designed organo‐layered silicates as nanoreactors for 1,3‐butadiene stereospecific polymerization toward rubber nanocomposites synthesis
Authors: Leone Giuseppe , Boglia Aldo , Bertini Fabio , Canetti Maurizio , Ricci Giovanni 
Published: September 2010

AbstractOrgano‐modified layered silicates were synthesized and used as inorganic carriers for CoCl2(PtBu2Me)2‐MAO catalyst in the polymerization of 1,3‐butadiene, yielding cis‐1,4‐enriched polybutadiene. The organoclays were prepared by: (i) intercalation of (ar‐vinyl‐benzyl)trimethyl ammonium chloride salt through an ion exchange reaction, and (ii) the edge‐surface grafting by trimethylchlorosilane. The ammonium modifier acts as “spacer” increasing the layer d‐spacing and as “filler” favoring the silylation of the edge‐surface clay hydroxyls. The grafted silane prevents the MAO cocatalyst from reacting with the edge‐OHs, by forcing it to react within the interlayer clay region. MAO lead to methylation of the cobalt complex and carbanion abstraction to give a cobalt‐methyl cation that is stabilized by the MAO anion. The nanoconfined cationic alkylated species insert the butadiene on the Co‐Me bond affording the growth of the polymer chains within the clay layers. The growing of the macromolecular chains fills the interlayer silicate region giving an intercalated polybutadiene rubber nanocomposite. The role of the silicate organo modification on the heterogeneous catalyst structural features, the polymerization behavior and the nanocomposite structures are discussed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Facile, one‐pot synthesis of aromatic diamine‐based phosphinated benzoxazines and their flame‐retardant thermosets
Authors: Lin Ching Hsuan , Lin Hung Tse , Sie Jhao Wei , Hwang Kuen Yuan , Tu An Pang 
Published: September 2010

AbstractThree aromatic diamine‐based, phosphinated benzoxazines (7–9) were prepared from three typical aromatic diamines—4,4′‐diamino diphenyl methane (1), 4,4′‐diamino diphenyl sulfone (2), and 4,4′‐diamino diphenyl ether (3) by a one‐pot procedure. To clarify the reaction mechanism, a two‐pot procedure was applied, in which the reaction intermediates (4–6) were isolated for characterization. The structures of intermediates and benzoxazines were confirmed by high resolution mass, IR, and 1D and 2D‐NMR spectra. In addition to self‐polymerization, (7–9) were copolymerized with cresol novolac epoxy (CNE). After curing, the homopolymers of P(7–9) are brittle while the copolymers of (7–9)/CNE are tough. Dynamic mechanical analysis shows the Tgs of (7–9)/CNE copolymers are 187, 190, and 171 °C, respectively. Thermal mechanical analysis shows the CTEs of (7–9)/CNE copolymers are 46, 38, and 46 ppm, respectively. All the (7–9)/CNE copolymers belong to an UL‐94 V‐0 grade, demonstrating good flame retardancy. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Self‐emulsification and surface modification effect of fluorinated amphiphilic acrylate graft copolymers
Authors: Cha Mi Sun , Kim Jae Won , Ha Jong‐Wook , Park In Jun , Lee Soo‐Bok , Yang Tingting , Cheng Shiyuan 
Published: September 2010

AbstractWe report on self‐emulsification and surface modification effect of novel fluorinated amphiphilic graft copolymers prepared with perfluoroalkyl acrylate and 2‐dimethylaminoethyl methacrylate using simple macromonomer technique and radical copolymerization. The interfacial properties of amphiphilic graft copolymers were characterized with light scattering, contact angle measurement, and X‐ray photoelectron spectroscopy. The preparation of fluorinated amphiphilic graft copolymer was verified using nuclear magnetic resonance and Fourier transform infrared spectroscopy. It was observed that the fluorinated amphiphilic graft copolymer has both strong hydrophobic and hydrophilic properties and shows self‐emulsification ability without addition of external surfactants. The graft copolymer shows very low surface energy even though the copolymer has low content of hydrophobic segment and better performance than random copolymer for low‐energy surface modification. The addition of small amount of the graft copolymer (0.1 wt %) into the base poly(methyl methacrylate) was sufficient to lower the surface energy less than that of poly(tetrafluoroethylene). © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Fundamental study of crystallization, orientation, and electrical conductivity of electrospun PET/carbon nanotube nanofibers
Authors: Mazinani Saeedeh , Ajji Abdellah , Dubois Charles 
Published: September 2010

AbstractThe morphology, structure, and properties of polyethylene terephthalate (PET)/Carbon Nanotubes (CNT) conductive nanoweb were studied in this article. Nanocomposite nanofibers were obtained through electrospinning of PET solutions in trifluoroacetic acid (TFA)/dichloromethane (DCM) containing different concentrations and types of CNTs. Electrical conductivity measurements on nanofiber mats showed an electrical percolation threshold around 2 wt % multi‐wall carbon nanotubes (MWCNT). The morphological analysis results showed smoother nanofibers with less bead structures development when using a rotating drum collector especially at high concentrations of CNTs. From crystallographic measurements, a higher degree of crystallinity was observed with increasing CNT concentrations above electrical percolation. Spectroscopy results showed that both PET and CNT orientation increased with the level of alignment of the nanofibers when the nanotube concentration was below the electrical percolation threshold; while the orientation factor was reduced for aligned nanofibers with higher content in CNT. Considerable enhancement in mechanical properties, especially tensile modulus, was found in aligned nanofibers; at least six times higher than the modulus of random nanofibers at concentrations below percolation. The effect of alignment on the mechanical properties was less important at higher concentrations of CNTs, above the percolation threshold. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2052–2064, 2010
Density functional study on the effect of substituent group for the monomer of donor‐acceptor copolymer
Authors: Sun Lei , Bai Fu‐Quan , Zhao Zeng‐Xia , Yang Bao‐Zhu , Zhang Hong‐Xing 
Published: September 2010

AbstractThe effect of the substituent groups (alkyl or aryl) on the structure, electronic, optical properties, ionization potentials (IPs), electron affinities (EAs), and reorganization energy of the donor–acceptor monomers 5,8‐di‐2‐thienyl‐quinoxaline (T[Q]T), 4,9‐di‐2‐thienylpyrazine[2,3‐g]quinoxaline (T[PQ]T) were studied theoretically. The lowest‐lying absorption in assigned to π→π* transition, and the fluorescence can be described as originating from the 1[ππ*] excited state. The lowest‐lying absorption and emission spectrum of T[Q]T and T[PQ]T with alkyl groups exhibit blue‐shifted, while T[Q]T and T[PQ]T with aryl groups exhibit the opposite result. The extra absorption bond at 400 nm of T[Q]T‐Bph is contributed by the π‐π* transitions between the biphenyl and acceptor fragment. Orbital compositions transfer coefficient (χ) of the donor in LUMOs is reduced with the aryl groups on the acceptor, which illuminates that the aryl contributes to intramolecular charge transfer, and the result is in accord with the analysis of reorganization energy. IPs is brought down by both of the alkyl and aryl groups, but EAs is raised only by aryl, therefore, aryl is conductive to forming excitons for D‐A‐D molecule. Consequently, T[Q]T and T[PQ]T with aryl groups are more reasonable monomers of donor–acceptor copolymers as a solar cell materials comparing with the alkyl‐introduced ones. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010
Dynamic light scattering studies of ionic and nonionic polymer gels with continuous and discontinuous volume transitions
Authors: Mccoy J. L. , Muthukumar M. 
Published: September 2010

AbstractWe have performed dynamic light scattering experiments on poly(acrylamide)‐poly(acrylic acid) copolymer gels with controlled crosslink density and copolymer composition, by varying the temperature, amount and valency of added salt, pH, and solvent quality. Our systematic study provides several insights. The correlation length for the monomer density fluctuations, as inferred from the measured diffusion coefficient, is too small to be identified as the mesh size of the gel. The correlation length in an ionic gel, which is found to be smaller than that for an equivalent gel without ionization. Comparison of swelling ratio with the diffusion coefficient shows that these quantities are not simply geometrically related to each other. When a discontinuous volume phase transition is induced by gradually varying the solvent quality, the diffusion coefficient exhibits a pretransitional reduction by two orders of magnitude even before the gel collapse. These findings provoke a need for new theoretical approaches for describing the elastic modes of polyelectrolyte gels. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010
Effect of PBT molecular weight and reactive compatibilization on the dispersed‐phase coalescence of PBT/SAN blends
Authors: Larocca Nelson M. , Ito Edson N. , Rios Carlos Triveño , Pessan Luiz A. , Bretas Rosario E. S. , Hage Elias 
Published: September 2010

AbstractPoly(butylene terephthalate) (PBT)/styrene‐acrylonitrile copolymer (SAN) blends were investigated with respect to their phase morphology. The SAN component was kept as dispersed phase and PBT as matrix phase and the PBT/SAN viscosity ratio was changed by using different PBT molecular weights. PBT/SAN blends were also compatibilized by adding methyl methacrylate‐co‐glycidyl methacrylate‐co‐ethyl acrylate terpolymer, MGE, which is an in situ reactive compatibilizer for melt blending. In noncompatibilized blends, the dispersed phase particle size increased with SAN concentration due to coalescence effects. Static coalescence experiments showed evidence of greater coalescence in blends with higher viscosity ratios. For noncompatibilized PBT/SAN/MGE blends with high molecular weight PBT as matrix phase, the average particle size of SAN phase does not depend on the SAN concentration in the blends. However noncompatibilized blends with low molecular weight PBT showed a significant increase in SAN particle size with the SAN concentration. The effect of MGE epoxy content and MGE molecular weight on the morphology of the PBT/SAN blend was also investigated. As the MGE epoxy content increased, the average particle size of SAN initially decreased with both high and low molecular weight PBT phase, thereafter leveling off with a critical content of epoxy groups in the blend. This critical content was higher in the blends containing low molecular weight PBT than in those with high molecular weight PBT. At a fixed MGE epoxy content, a decrease in MGE molecular weight yielded PBT/SAN blends with dispersed nanoparticles with an average size of about 40 nm. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010
The crystal–crystal transition in hydrogenated ring‐opened polynorbornenes: Tacticity, crystal thickening, and alignment
Authors: Bishop John P. , Register Richard A. 
Published: September 2010

AbstractAt a temperature Tcc well below its melting point Tm, hydrogenated ring‐opened polynorbornene (hPN) is known to exhibit a crystal–crystal transition; above Tcc, the hPN chains are rotationally disordered. This transition is examined in a series of hPNs polymerized with different Mo‐ and Ru‐based catalysts, each of which imparts a slightly different tacticity to the polymer. Tcc is found to correlate well with the ratio of meso to racemo dyads (m:r); small changes in m:r (from 0.8 to 1.1) are sufficient to raise Tcc by nearly 20 °C. For the homogeneous Mo‐based “Schrock‐type” catalyst examined, such a change in m:r is easily achieved by simply adding the reversibly binding ligand trimethylphosphine during polymerization. Tcc approaches Tm with increasing m:r, indicating that r dyads stabilize the rotationally disordered structure. When heated above Tcc, hPN crystals thicken at a rate much greater than conventional three‐dimensionally ordered crystals, but below the rates shown by the two‐dimensional hexagonal (columnar) phase formed by some polymers, reflecting the intermediate level of order and chain mobility present in the high‐temperature hPN crystal phase. Solid‐state processing of hPN between Tcc and Tm yields highly aligned macroscopic specimens. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010