bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization, chain mobility, and thermal properties of the hydrophilic poly(methyl methacrylate‐co‐acrylic acid) colloids
Authors: Shih Chien‐Chou , Wu Kuo‐Hui , Chang Te‐Chuan , Liu Hsing‐Kwo 
Published: December 2007

AbstractAn amphiphilic colloidal copolymer containing methyl methacrylate (MMA) and sodium acrylate at different compositions was prepared by a free‐emulsion polymerization method with potassium persulfate as an initiator, and it was then doped in HCl solution to obtain the acid form poly(methyl methacrylate‐co‐acrylic acid) (PMMAA) copolymer. The copolymers were characterized by means of gel permeation chromatography, 1H nuclear magnetic resonance spectrometer, 13C solid‐state nuclear magnetic resonance spectrometer, infrared spectra, and differential scanning calorimeter. The copolymers have only a single, and nearly constant, glass transition temperature of 124°C, at which there is no observable effect on the structure of the copolymer. The monomer reactivity ratios rNaAA and rMMA were rNaAA = 1.06, rMMA = 0.70 and rNaAA = 1.02, and rMMA = 0.63 estimated respectively by using the classical Fineman‐Ross and the Kelen‐Tüdös methods. The results revealed that the copolymer had a tendency towards the formation of small acrylic acid blocks that have very short segments of MMA. The proton spin‐lattice relaxation time in the rotating frame T indicated single composition‐dependent for all copolymers, which imply dynamic homogeneity and a good miscibility with chain dynamics on the upper spatial scale of 3 nm existed in the PMMAA copolymer. An increase of the thermal stability of the copolymers was shown from the apparent activation energy of the thermal degradation process for the copolymers relative to the homopolymers. POLYM. COMPOS., 29:37–44, 2008. © 2007 Society of Plastics Engineers
Discussion of aqueous urethane acrylate oligomers with sulfoisophthalate on the antistatic hydrophilic finishing of different fabrics
Authors: Yen Meng‐Shung , Huang Ching‐Nan , Hong Po‐Da 
Published: December 2007

AbstractIn this study, PEG(SE) containing sulfonic acid group was produced by transesterification of dimethyl 5‐sulfoisophthalate sodium salt (SIP) with PEG. The reactive urethane acrylate oligomers were synthesized by using SE as soft segment, isophorone diisocyanate (IPDI) as hard segment, and hydroxyethyl methacrylate (HEMA) as blocking agent. Their solution properties and thermal properties were investigated. Dipping process was carried out on polyethylene terephthalate (PET) fabric, polyamide (nylon) fabric, and cotton fabric for hydrophilic finishing and the effects of processing condition on the fixation behavior and hydrophilic property of treated fabric have been discussed. The conclusions are as follows: the particle size of oligomer solutions are about 45–90 μm, surface tension of solutions are below 43 dyn/cm, and they have smaller contact angle than water. The particle size, particle variance, and streaming current reading decreased, but the surface tension and contact angle enhanced upon increasing PEG molecular weight. The melting point of oligomer is 38°C–52°C and the glass transition point is −18°C to −25°C. In comparison with the fabric finishing, the add‐on of PET fabric is the highest, followed by nylon, then cotton. The durability of treated cotton fabric is the highest, followed by PET, then nylon. The hydrophilicity is most stable for nylon fabric with PEG molecular weight of 2,000, and cotton and PET fabric with molecular weight of 1,000. POLYM. COMPOS., 29:45–57, 2008. © 2007 Society of Plastics Engineers
Effects of small‐amplitude oscillatory shear on polymeric reaction
Authors: Xie Fan , Zhou Chixing , Yu Wei 
Published: December 2007

AbstractThe effects of small‐amplitude oscillatory shear on the polymeric reaction between poly(butylene terephthalate) (PBT) and epoxy in melts were studied. Two kinds of samples, sandwich sample and blending sample, were prepared for reaction kinetics by using a new rheological method which correlates the change of the rheological property of reactive system with the conversion of the in situ formed copolymers. The results indicated that the reaction between PBT and epoxy was hardly affected by the small‐amplitude oscillatory shear. The increase of apparent reaction rate in sandwich sample was due to the increase of molecular diffusion by oscillatory shear. POLYM. COMPOS., 29:72–76, 2008. © 2007 Society of Plastics Engineers
Reactions of aryl chlorothionoformates with quinuclidines. A kinetic study
Authors: Castro Enrique A. , Aliaga Margarita , Campodonico Paola R. , Leis J. Ramón , García‐Río Luis , Santos José G. 
Published: December 2007

AbstractThe reactions of quinuclidines with phenyl, 4‐chlorophenyl, 4‐cyanophenyl, and 4‐nitrophenyl chlorothionoformates (1, 2, 3, and 4, respectively) are subjected to a kinetic study in aqueous solution, at 25.0°C, and an ionic strength of 0.2 M (KCl). The reactions are studied by following spectrophotometrically the release of the corresponding phenoxide anion/phenol generated in the parallel hydrolysis of the substrates. Under amine excess, pseudo‐first‐order rate coefficients (kobs) are found. Plots of kobs versus [amine] are linear, with slope kN. The Brønsted‐type plots (log kN vs. pKa of aminium ions) are linear, with slopes β = 0.26, 0.22, 0.19, and 0.28 for the reactions with 1, 2, 3, and 4, respectively. The magnitudes of the slopes indicate that these mechanisms are stepwise, with rate‐determining formation of a zwitterionic tetrahedral intermediate (T±). A dual parametric equation with the pKa of the nucleophiles and non‐leaving groups show βN = 0.26 and βnlg = −0.16, also in accordance with the proposed mechanism. On the other hand, the reactivity of these thiocarbonyl substrates and their carbonyl derivatives was studied using their hardness index and compared with their experimental parameters, confirming the proposed mechanisms. By comparison of the title reactions with similar aminolyses, the following conclusions arise: (i) The mechanism of the reactions under investigation is stepwise with rate‐determining formation of T±. (ii) The reactivity of the substrates toward quinuclidines follows the order 4 > 3 > 2 > 1. (iii) Quinuclidines are more reactive than isobasic pyridines toward chlorothionoformates. (iv) Chlorothionoformates are less reactive than chloroformates towards quinuclidines in accordance with the HSAB principle. (v) The kN values for phenyl chloroformate and 4 can be correlated with the pKa of quinuclidines and also with the hardness values calculated by the HF/3‐21G level of theory. Copyright © 2007 John Wiley & Sons, Ltd.
Microporous membranes obtained from polypropylene blends with superior permeability properties
Authors: Sadeghi Farhad , Ajji Abdellah , Carreau Pierre J. 
Published: December 2007

AbstractA blend of two polypropylene resins, different in molecular structure, one with linear chains and the other with long chain branches, was investigated to develop microporous membranes through melt extrusion (cast film process) followed by film stretching. The branched component significantly affected the row‐nucleated lamellar crystalline structure in the precursor films. The arrangement and orientation of the crystalline and amorphous phases were examined by wide angle X‐ray diffraction and Fourier transform infrared spectroscopy methods. It was found that blending of a small amount of a long chain branched polypropylene improved the orientation of the both crystalline and amorphous phases in the precursor films. Annealing, followed by cold and hot stretching were consequently employed to generate and enlarge pores in the films as a result of lamellae separation. SEM micrographs of the surface of the membranes obtained from the blend revealed elongated thin fibrils and a large number of lamellae. The lamellae thickness for the blend was much shorter in comparison to that of the linear PP precursor film. The permeability of the samples to water vapor and N2 was significantly enhanced (more than twice) for the blend system. The porosity of the blend membrane showed a significant improvement with a value of 53% compared to 41% for the linear PP membrane. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 148–157, 2008
Isothermal and nonisothermal crystallization kinetics of nylon 6/functionalized multi‐walled carbon nanotube composites
Authors: Chen Erh‐Chian , Wu Tzong‐Ming 
Published: December 2007

AbstractThe well dispersion of functionalized multi‐walled carbon nanotube (f‐MWCNT) in nylon 6 matrix was prepared by solution mixing techniques. The isothermal and nonisothermal crystallization kinetics of nylon 6 and nylon 6/f‐MWCNT nanocomposites were studied by differential scanning calorimetry (DSC), X‐ray diffraction and polarized optical microscopy analysis. DSC isothermal results revealed that the activation energy of nylon 6 extensively decreased by adding 1 wt % f‐MWCNT into nylon 6, suggesting that the addition of small amount of f‐MWCNT probably induces the heterogeneous nucleation. Nevertheless, the addition of more f‐MWCNT into nylon 6 matrix reduced the transportation ability of polymer chains during crystallization process and thus increased the activation energy. The nonisothermal crystallization of nylon 6/f‐MWCNT nanocomposites was also discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 158–169, 2008
Tumor antigens eliciting autoantibody response in cancer of gingivo‐buccal complex
Authors: Shukla Sanjeev , Govekar Rukmini B. , Sirdeshmukh Ravi , Sundaram Curam S. , D'Cruz Anil K. , Pathak K. Alok , Kane Shubhada V. , Zingde Surekha M. 
Published: December 2007

AbstractCancer of the gingivo‐buccal complex (GBC) is a major cancer in Indian men. This study reports the identification of tumor antigens, which elicit an antibody response in cancer of GBC using immunoproteomics. Proteins from KB cells separated by 2‐D PAGE, were immunoblotted with IgG from sera of 28 cancer patients, 12 patients with leukoplakia, and 28 healthy individuals. Antigens detected by the IgGs from the patient's sera were different among different individuals with presence of any single antigen ranging from 7 to 79%. Several of these antigens have been identified by MS and confirmed by immunostaining. They are three forms of α‐enolase, peroxiredoxin‐VI, annexin‐II, HSP70, pyruvate kinase, α‐tubulin, β‐tubulin, ATP‐synthase, phosphoglycerate mutase (PGM), aldose reductase, triosephosphate isomerase, and cyclophilin‐A. Except, HSP70, these antigens are being reported in cancer of GBC for the first time. Pyruvate kinase and aldose reductase have not been reported to elicit autoantibody response in any other cancer earlier. Initial results show that autoantibody response against α‐enolase, HSP70, annexin‐II, peroxiredoxin‐VI, and aldose reductase are also seen in patients with leukoplakia of GBC, which suggest early occurrence of these autoantibodies during the process of oral carcinogenesis. These antigens can be further validated for their use in cancer management by immune intervention.
Toxicoproteomics and its application to human health risk assessment
Authors: Ge Yue , Preston R. Julian , Owen Russell D. 
Published: December 2007

AbstractToxicoproteomics is the use of proteomic technologies to better understand environmental and genetic factors, toxic mechanisms, and modes of action in response to acute exposure to toxicants and in the long‐term development of diseases caused or influenced by these exposures. Use of toxicoproteomic technologies to identify key biochemical pathways, mechanisms, and biomarkers of exposure and toxicity will decrease the uncertainties that are associated with human health risk assessments. This review provides an overview of toxicoproteomics from human health risk assessment perspectives. Key toxicoproteomic technologies such as 2‐D gel‐based proteomic methods and toxicoproteomic approaches are described, and examples of applications of these technologies and methodologies in the risk assessment context are presented. The discussion includes a focus on challenges and future directions.
Grand Rounds in Proteomics at the FDA White Oak, Silver Spring, MD, USA, April 3, 2007
Authors: Goodsaid Federico , Bandow Julia Elisabeth , Mischak Harald 
Published: December 2007

AbstractThe application of proteomics in drug development could be a major source of novel biomarkers to improve the efficacy and safety of new drugs. Training of US Food and Drug Administration (FDA) reviewers on current applications of proteomics is important for the future review of proteomic data.A Grand Rounds in Proteomics was held on April 3, 2007 at the FDA in White Oak, Silver Spring, MD, USA. The goal of this activity was to contribute to reviewer training as well as to generate discussions regarding the readiness of proteomic platforms in drug development, similar in scope to applications in genomics and metabolomics. Several speakers from industry and academia presented data on proteomic applications in drug development (meeting agenda available in the Supporting Information).An additional goal of this meeting was to encourage proteomic data submissions within the Voluntary eXploratory Data Submissions (VXDS) at the FDA. VXDS meetings represent key venues for exchange between the FDA and sponsors of scientific and clinical data on exploratory biomarkers. The FDA has received a limited number of VXDS submissions containing proteomic data. This meeting was an opportunity to identify possible areas in proteomics where future VXDS submissions may be received. Voluntary submissions have been transformed into regulatory submissions in genomics, and a similar path may also be followed by proteomic data in the future. Proteomic biomarkers may also be suitable for submission to the Pilot Process for Biomarker Qualification at the FDA.
Effect of aqueous‐ethanol extract from Crocus sativus (saffron) on guinea‐pig isolated heart
Authors: Boskabady M. H. , Shafei M. N. , Shakiba A. , Sefidi H. Sang 
Published: December 2007

AbstractIn this study, the effects of an aqueous‐ethanol extract from Crocus sativus on heart rate and contractility were examined. Isolated guinea‐pig hearts were perfused through the aorta in a Langendorff mode. Heart rate and contractility were determined in the presence of four concentrations of the extract (0.1, 0.5, 1.0 and 5.0 mg%) and diltiazem (0.1, 1, 10 and 100 µm) in perfused heart with: (1) ordinary Krebs solution (group 1, n = 9), (2) calcium‐free Krebs solution (group 2, n = 7). In group 1, three higher concentrations of diltiazem (1, 10 and 100 µm), but only the highest (5.0 mg%) and two higher concentrations (1.0 and 5.0 mg%) of the extract caused significant reduction in heart rate and contractility, respectively (p < 0.05 to p < 0.001). In group 2, the highest (100 µm) and two higher concentrations (10 and 100 µm) of diltiazem (p < 0.05 to p < 0.01), but only the highest concentration of the extract showed significant reductions in the heart rate and contractility (p < 0.05 to p < 0.01). There were significant negative correlations between concentrations of the extract and diltiazem and their effects in both groups (p < 0.01 to p < 0.001). These results suggested a potent inhibitory effect of aqueous‐ethanol extract from C. sativus on the calcium channel of guinea‐pig heart. Copyright © 2007 John Wiley & Sons, Ltd.
A new antifungal and antiprotozoal depside from the andean lichen Protousnea poeppigii
Authors: Schmeda‐Hirschmann Guillermo , Tapia Alejandro , Lima Beatriz , Pertino Mariano , Sortino Maximiliano , Zacchino Susana , Arias Antonieta Rojas de , Feresin Gabriela Egly 
Published: December 2007

AbstractExtracts from the Andean lichens Protousnea poeppigii and Usnea florida displayed antimicrobial activity against the pathogenic fungi Microsporum gypseum, Trichophyton mentagrophytes and T. rubrum with MIC values between 50 and 100 µg/mL. From the active extracts, four main metabolites were isolated and identified as the new depside, isodivaricatic acid, and the known metabolites 5‐propylresorcinol, divaricatinic acid and usnic acid. Isodivaricatic acid and divaricatinic acid presented antifungal effect towards M. gypseum with a MIC of 50 µg/mL and against T. mentagrophytes and T. rubrum and with MIC values of 50 and 100 µg/mL, respectively. The new isodivaricatic acid was active towards Leishmania amazonensis, Leishmania brasiliensis and Leishmania infantum promastigotes with 100% lysis at 100 µg/mL.The activity of the new compound decreased on acetylation of the hydroxy groups as well as on methylation of the acid function. The structures were elucidated by spectroscopic means. The spectroscopic data of isodivaricatic acid are presented here for the first time. Copyright © 2007 John Wiley & Sons, Ltd.
Hypolipidemic activity of Anethum graveolens in rats
Authors: Hajhashemi Valiollah , Abbasi Naser 
Published: December 2007

AbstractThe aerial parts of Anethum graveolens (dillweed) are used in Iran as a hypolipidemic agent. The scientific basis for its use has yet to be established. In this study the hypolipidemic activity of dill powder and its essential oil (its most important fraction) were evaluated in male Wistar rats (180 ± 20 g) fed a high cholesterol diet. Anethum graveolens essential oil (AGEO) was prepared by hydrodistillation and analysed using GC/MS. AGEO had a yield of 2% and GC/MS analysis showed that α‐phellandrene (32%), limonene (28%) and carvone (28%) were its major components. Daily oral administration of AGEO to rats at doses of 45, 90 and 180 mg/kg for 2 weeks significantly and in a dose‐dependent manner reduced total cholesterol, triglyceride and low density lipoprotein cholesterol (LDL‐C). AGEO also increased significantly high density lipoprotein cholesterol (HDL‐C). Anethum graveolens powder when added to the diet of animals showed similar effects on serum lipids. It is concluded that Anethum graveolens has significant lipid lowering effects and is a promising cardioprotective agent. Copyright © 2007 John Wiley & Sons, Ltd.
Verticinone induces cell cycle arrest and apoptosis in immortalized and malignant human oral keratinocytes
Authors: Yun Young‐Gab , Jeon Byung‐Hun , Lee Jong‐Hyun , Lee Sun‐Kyung , Lee Hwa‐Jeong , Jung Kyung‐Hee , Jun‐Lee  , Jun Chang‐Duk , Lee Suk‐Keun , Kim Eun‐Cheol 
Published: December 2007

AbstractAlthough verticinone, a major alkaloid isolated from the bulbus of Fritillaria ussuriensis, has been shown to induce differentiation in human leukemia cells, the exact mechanism of this action is not completely understood in cancer cells. Verticinone was used to conduct growth and apoptosis‐related experiments for two stages of oral cancer on immortalized human oral keratinocytes (IHOKs) and primary oral cancer cells (HN4). The procedures included MTT assay, three‐dimensional (3‐D) raft cultures, Western blotting, cell cycle analysis, nuclear staining and cytochrome c expression related to the apoptosis signaling pathway. Verticinone inhibited the proliferation of immortalized and malignant oral keratinocytes in a dose‐ and time‐dependent manner. In 3‐D organotypic culture, verticinone‐treated cells were less mature than the control cells, displaying low surface keratinization and decreased epithelial thickness. The major mechanism by which verticinone inhibits growth appears to be induced apoptosis and G0G1 cell cycle arrest. This finding is supported by the results of the cell cycle analysis, FITC‐Annexin V staining, DNA fragmentation assay and Hoechst 33258 staining. Furthermore, the cytosolic level of cytochrome c was increased, while the expression of Bcl‐2 protein was gradually down‐regulated and Bax was up‐regulated, accompanied by caspase‐3 activation. The data suggests that verticinone may induce apoptosis through a caspase pathway mediated by mitochondrial damage in immortalized keratinocytes and oral cancer cells. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of triacetone triperoxide (TATP) and TATP synthetic intermediates by electrospray ionization mass spectrometry
Authors: Sigman Michael E. , Clark C. Douglas , Caiano Tara , Mullen Rebecca 
Published: December 2007

AbstractThe explosive triacetone triperoxide (TATP) has been analyzed by electrospray ionization mass spectrometry (ESI‐MS) on a linear quadrupole instrument, giving a 62.5 ng limit of detection in full scan positive ion mode. In the ESI interface with no applied fragmentor voltage the m/z 245 [TATP + Na]+ ion was observed along with m/z 215 [TATP + Na – C2H6]+ and 81 [(CH3)2CO + Na]+. When TATP was ionized by ESI with an applied fragmentor voltage of 75 V, ions at m/z 141 [C4H6O4 + Na]+ and 172 [C5H9O5 + Na]+ were also observed. When the precipitates formed in the synthesis of TATP were analyzed before the reaction was complete, a new series of ions was observed in which the ions were separated by 74 m/z units, with ions occurring at m/z 205, 279, 353, 427, 501, 575, 649 and 723. The series of evenly spaced ions is accounted for as oligomeric acetone carbonyl oxides terminated as hydroperoxides, [HOOC(CH3)2{OOC(CH3)2}nOOH + Na]+ (n = 1, 2 … 8). The ESI‐MS spectra for this homologous series of oligoperoxides have previously been observed from the ozonolysis of tetramethylethylene at low temperatures. Precipitates from the incomplete reaction mixture, under an applied fragmentor voltage of 100 V in ESI, produced an additional ion observed at m/z 99 [C2H4O3 + Na]+, and a set of ions separated by 74 m/z units occurring at m/z 173, 247, 321, 395, 469 and 543, proposed to correspond to [CH3CO{OOC(CH3)2}nOOH + Na]+ (n = 1,2 … 5). Support for the assigned structures was obtained through the analysis of both protiated and perdeuterated TATP samples. Copyright © 2007 John Wiley & Sons, Ltd.
Plant cover estimation based on the beta distribution in grassland vegetation
Authors: Chen Jun , Shiyomi Masae , Bonham Charles D. , Yasuda Taisuke , Hori Yoshimichi , Yamamura Yasuo 
Published: December 2007

AbstractCover is the most frequently used measure of abundance in vegetation surveys of grasslands, and various qualitative and semi‐quantitative methods have been developed for visual estimation of this metric. Field survey is usually made with a point‐grid plate. The frequency distributions of cover derived from point‐grid counts follow a beta distribution. Combining point‐grid counts from a field survey and the beta distribution for a statistical analysis, we developed an effort‐saving cover‐measurement method. Cover is measured with a transparent plastic plate on which, for example, 10 × 10 = 100 points are arranged in a lattice with 1‐cm grid spacing (thus, one point count represents 1 cm2 of cover). N quadrats are set out at randomly dispersed sites in a grassland, and, in each, the plastic plate is used for making counts. The number of grid points located above a given species is counted in every quadrat until the number of counted points reaches a given value c, which is determined in advance. If the number of counted points reaches c in a quadrat, the count is stopped and the quadrat is classified in the category “>c”. In quadrats where c is not attained, full point counts above the species bodies are made. Let g be the number of observed quadrats whose cover is ≤c. Using these g cover measurements and the number of quadrats (N − g) with cover >c, we can quantitatively estimate cover for each species and the spatial pattern index value based on the maximum likelihood method. In trial counts using this method, the time savings varied between 5% and 41%, depending on the shape of the cover frequency distribution. The mean cover value estimates agreed well with conventional measures without a stopping point (i.e., based on full counts of all points in each quadrat).