bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of saccharides and phenolic acids in the Chinese herb Tanshen by ESI‐FT‐ICR‐MS and HPLC
Authors: Li Huilin , Song Fengrui , Zheng Zhong , Liu Zhiqiang , Liu Shuying 
Published: August 2008

AbstractThis study sought to determine the main components (saccharides and phenolic acids) in crude extract of the Chinese herb Tanshen by electrospray ionization Fourier transform ion cyclotron resonant mass spectrometry (ESI‐FT‐ICR‐MS) in negative‐ion mode. Eleven compounds were identified as phenolic acids by exact mass measurement and further confirmed by sustained off‐resonance irradiation (SORI) CID data. In addition, monosaccharides and oligosaccharides (n = 2 ∼ 5) and a serial of corresponding anionic adducts of saccharide were observed without adding any anions additionally to the extract solution, and the anionic components were unambiguously identified as H2O, HCl, HCOOH, HNO3, C3H6O2, H2SO4 and C5H7NO3 according to the exact mass measurement results. Furthermore, the saccharide types in Tanshen extract were identified as raffitrinose, saccharose, glucose, galactose and fructose with HPLC by comparing standards. Copyright © 2008 John Wiley & Sons, Ltd.
A fast screening MALDI method for the detection of cocaine and its metabolites in hair
Authors: Vogliardi Susanna , Favretto Donata , Frison Giampietro , Ferrara Santo Davide , Seraglia Roberta , Traldi Pietro 
Published: August 2008

AbstractMatrix‐assisted laser desorption/ionisation (MALDI) mass spectrometry was used for the rapid detection of cocaine, benzoylecgonine and cocaethylene in hair. Different MALDI sample preparation procedures have been tested and the employment of a multi‐layer ‘graphite–sample–electrosprayed α‐cyano‐4‐hydroxycinnamic acid (HCCA)’ yielded the best results for standard solutions of the target analytes. The same approach was subsequently applied to hair samples that were known to contain cocaine, benzoylecgonine and cocaethylene, as determined by a classical GC‐MS method. It was however necessary to extract hair samples by incubating them in methanol/trifluoroacetic acid for a short time (15 min) at 45 °C; 1 µl of the obtained supernatant was deposed on a metal surface treated with graphite, and HCCA was electrosprayed on it. This procedure successfully suppressed matrix peaks and was effective in detecting all the target analytes as their protonated species. The results obtained give further confirmation of the effectiveness of the MALDI for detecting drugs and their metabolites in complex biological matrices. The method can be useful as a fast screening procedure to detect the presence of cocaine and metabolites in hair samples. Copyright © 2008 John Wiley & Sons, Ltd.
Co‐oxidation of ammonia and ethanol in supercritical water, part 2: Modeling demonstrates the importance ofH2NNOx
Authors: Ploeger Jason M. , Green William H. , Tester Jefferson W. 
Published: August 2008

AbstractA co‐oxidation model was constructed from available submechanisms for ammonia and ethanol oxidation. The ammonia submechanism validated for combustion at atmospheric pressure conditions was modified for the higher densities and lower temperatures (655–700°C) of supercritical water. The ethanol submechanism had previously been tested and validated at supercritical water conditions. The initial model poorly reproduced experimental ammonia conversion data and was not able to consistently match nitrous oxide production as a function of temperature over a range from 655–700°C at 246 bar. To improve model predictions, the low‐pressure NH2+ NOxsubmechanism was replaced with a submechanism that included the H2NNOxadduct species that are expected to be stabilized in the high‐pressure supercritical water environment. Thermochemical and kinetic parameters for the adduct species were estimated with quantum chemical calculations using Gaussian 98 with the CBS‐Q method. The explicit treatment of the H2NNOxadducts resulted in nitrous oxide yield predictions that correctly reproduced experimental trends. This work represents a vital first step in improving the understanding of ammonia oxidation in supercritical water. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 653–662, 2008
Rate coefficients for the OH + acetaldehyde (CH3CHO) reaction between 204 and 373 K
Authors: Zhu Lei , Talukdar Ranajit K. , Burkholder James B. , Ravishankara A. R. 
Published: August 2008

AbstractThe rate coefficient, k1, for the gas‐phase reaction OH + CH3CHO (acetaldehyde) → products, was measured over the temperature range 204–373 K using pulsed laser photolytic production of OH coupled with its detection via laser‐induced fluorescence. The CH3CHO concentration was measured using Fourier transform infrared spectroscopy, UV absorption at 184.9 nm and gas flow rates. The room temperature rate coefficient and Arrhenius expression obtained are k1(296 K) = (1.52 ± 0.15) × 10−11 cm3 molecule−1 s−1 and k1(T) = (5.32 ± 0.55) × 10−12 exp[(315 ± 40)/T] cm3 molecule−1 s−1. The rate coefficient for the reaction OH (ν = 1) + CH3CHO, k7(T) (where k7 is the rate coefficient for the overall removal of OH (ν = 1)), was determined over the temperature range 204–296 K and is given by k7(T) = (3.5 ± 1.4) × 10−12 exp[(500 ± 90)/T], where k7(296 K) = (1.9 ± 0.6) × 10−11 cm3 molecule−1 s−1. The quoted uncertainties are 2σ (95% confidence level). The preexponential term and the room temperature rate coefficient include estimated systematic errors. k7 is slightly larger than k1 over the range of temperatures included in this study. The results from this study were found to be in good agreement with previously reported values of k1(T) for temperatures <298 K. An expression for k1(T), suitable for use in atmospheric models, in the NASA/JPL and IUPAC format, was determined by combining the present results with previously reported values and was found to be k1(298 K) = 1.5 × 10−11 cm3 molecule−1 s−1, f(298 K) = 1.1, E/R = 340 K, and Δ E/R (or g) = 20 K over the temperature range relevant to the atmosphere. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 635–646, 2008
A shock tube study of cyclopentane and cyclohexane ignition at elevated pressures
Authors: Daley Shane M. , Berkowitz Andrew M. , Oehlschlaeger Matthew A. 
Published: August 2008

AbstractIgnition delay times for cyclopentane/air and cyclohexane/air mixtures were measured in a shock tube at temperatures of 847–1379 K, pressures of 11–61 atm, and equivalence ratios of ϕ = 1.0, 0.5, and 0.25. Ignition times were determined using electronically excited OH emission monitored through the shock tube endwall and piezoelectric pressure measurements made in the shock tube sidewall. The dependence of ignition time on pressure, temperature, and equivalence ratio is quantified and correlations for ignition time formulated. Measured ignition times are compared to kinetic modeling predictions from four recently published mechanisms. The data presented provide a database for the validation of cycloalkane kinetic mechanisms at the elevated pressures found in practical combustion engines. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 40: 624–634, 2008
Mechanical and Thermal Properties of Green Polylactide Composites with Natural Fillers
Authors: Lezak Emil , Kulinski Zbigniew , Masirek Robert , Piorkowska Ewa , Pracella Mariano , Gadzinowska Krystyna 
Published: August 2008

AbstractGreen composites of PLA with micropowders derived from agricultural by‐products such as oat husks, cocoa shells, and apple solids that remain after pressing have been prepared by melt mixing. The thermal and mechanical properties of the composites, including the effect of matrix crystallization and plasticization with poly(propylene glycol), have been studied. All fillers nucleated PLA crystallization and decreased the cold‐crystallization temperature. They also affected the mechanical properties of the compositions, increasing the modulus of elasticity but decreasing the elongation at break and tensile impact strength although with few exceptions. Plasticization of the PLA matrix improved the ductility of the composites.magnified image
Tetronic–Oligolactide–Heparin Hydrogel as a Multi‐Functional Scaffold for Tissue Regeneration
Authors: Go Dong Hyun , Joung Yoon Ki , Lee Sang Young , Lee Myung Chul , Park Ki Dong 
Published: August 2008

AbstractA novel cell‐supporting scaffold, Tetronic–oligolactide–heparin (TLH) hydrogel, was prepared by coupling heparin to polymerized Tetronic–oligolactide for use in improving tissue regeneration. Aqueous TLH solutions showed thermosensitive behavior, demonstrating potential for use as injectable hydrogels. The content and activity of conjugated heparin were determined to be 61 wt.‐% of total polymer and 67.2% of intact heparin activity, respectively. The basic fibroblast growth factor (bFGF) binding assay showed TLH hydrogel had a relatively high bFGF affinity, which indicates applicability for growth factor delivery. Chondrocyte culture on hydrogels revealed that the cell viability and the amount of synthesized glycosaminoglycan for TLH hydrogel were higher than those for alginate gel.magnified image
Design and Synthesis of Phosphorescent Iridium Containing Dendrimers for Potential Applications in Organic Light‐Emitting Diodes
Authors: Liu Qin‐De , Lu Jianping , Ding Jianfu , Tao Ye 
Published: August 2008

AbstractThree phosphorescent dendrimers (IrC1, IrC3, and IrF2) with an iridium complex core and oligocarbazole or oligofluorene substituted ligands were synthesized and characterized. The structures of the oligocarbazole were designed to maintain high triplet energy of the ligands so that phosphorescence quenching in the resulting dendrimers can be prevented, while the oligofluorene in IrF2 resulted in undesired phosphorescence quenching. Best performance was obtained from an IrC3 based electrophosphorescent light‐emitting device with a maximum luminance of 13 060 cd · m−2 at a driving voltage of 11.5 V and a peak current‐efficiency of 4.3 cd · A−1 at a luminance of 3 400 cd · m−2, owing to its high PL efficiency, and efficient energy transfer between the iridium complex core and the ligands.magnified image
Thermosensitive gradient copolymers by living cationic polymerization: Semibatch precision synthesis and stepwise dehydration‐induced micellization and physical gelation
Authors: Seno Ken‐Ichi , Tsujimoto Itsuko , Kikuchi Takunobu , Kanaoka Shokyoku , Aoshima Sadahito 
Published: August 2008

AbstractThermosensitive forced gradient copolymers with various sequence distributions were synthesized by living cationic polymerization in the presence of an added base. The synthesis was conducted using a semibatch reaction method, which is unfavorable for ionic polymerization, especially when a simple apparatus is employed. Polymerization of 2‐ethoxyethyl vinyl ether (EOVE) was initiated using a conventional syringe technique. Immediately after initiation, 2‐methoxyethyl vinyl ether (MOVE) was continuously added using a syringe pump at regulated feed rates, which allowed control of the sequence distribution. The resulting gradient copolymers of EOVE and MOVE underwent thermally induced association in water, forming micelles with a hydrophobic core derived from EOVE‐rich segments. Interestingly, the size of the micelles obtained from gradient copolymers decreased monotonously with increasing solution temperature, while the micelles of the corresponding block copolymers were unchanged in size. This self‐association behavior can be controlled by designing the gradient pattern of the instantaneous composition. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6151–6164, 2008
Preparation of polyimide/silica hybrid material by sol–gel process under basic catalysis: Comparison with acid conditions
Authors: Didier Benoît , Mercier Régis , Alberola Nicole D. , Bas Corine 
Published: August 2008

AbstractHybrid polyimide/silica materials were prepared from polyimides bearing reactive functions along the polymer backbone, which can react with. The silica phase was formed by sol–gel process using ammonium hydroxide catalyst. Silica fillers prepared under basic conditions were compared with materials prepared using chlorhydric acid. The synthesized hybrid materials were characterized by TGA, IRTF, and NMR. The density of the different systems was also measured. The morphology of these hybrid systems were investigated by both scanning and transmission electron microscope. Thermal properties of the composites were also evaluated by DSC and DMA. The morphology of silica fillers highly depends on the catalyst, on the reaction conditions of the sol–gel process, and the linking formation with the polyimide. It results that optimized conditions lead to homogeneous hybrid films containing 12 wt % of silica particles of about 20 nm. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1891–1902, 2008
Interaction of SWCNT and PPTA with sulfuric acid—Compatibilization of two materials in a common solvent
Authors: Vlasveld Daniel P. N. , Fischer Hartmut R. , Swierenga Erik , Picken Stephen J. 
Published: August 2008

AbstractThe results of a calorimetric study on the melting and crystallization behavior of concentrated sulfuric acid containing dispersed single wall carbon nanotubes (SWCNT), dissolved water, and dissolved poly‐p‐phenyleneterphthalate (PPTA) polymer are presented. The measured reduction of the heat of crystallization is caused by the build‐up of an associated layer of structured acid molecules around SWCNT and PPTA. The freezing point depression is related to the number of dissolved species such as ions. It is shown that this theory accurately describes the experimental data for dissolved water and sulfur trioxide, but not for large molecules such as SWCNT. A mechanism for the interaction between sulfuric acid and SWCNT is proposed, based on preferred adsorption of sulfur trioxide and dissociation of sulfuric acid, leading to an increased number of dissolved low‐molecular‐weight species. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1914–1922, 2008
Investigation on LCST behavior of a new amorphous/crystalline polymer blend: Poly(n‐methyl methacrylimide)/poly(vinylidene fluoride)
Authors: Hu Huixia , Shangguan Yonggang , Zuo Min , Zheng Qiang 
Published: August 2008

AbstractThe liquid–liquid phase‐separation (LLPS) behavior of poly(n‐methyl methacrylimide)/poly(vinylidene fluoride) (PMMI/PVDF) blend was studied by using small‐angle laser light scattering (SALLS) and phase contrast microscopy (PCM). The cloud point (Tc) of PMMI/PVDF blend was obtained using SALLS at the heating rate of 1 °C min−1 and it was found that PMMI/PVDF exhibited a low critical solution temperature (LCST) behavior similar to that of PMMA/PVDF. Moreover, Tc of PMMI/PVDF is higher than its melting temperature (Tm) and a large temperature gap between Tc and Tm exists. At the early phase‐separation stage, the apparent diffusion coefficient (Dapp) and the product (2Mk) of the molecules mobility coefficient (M) and the energy gradient coefficient (k) arising from contributions of composition gradient to the energy for PMMI/PVDF (50/50 wt) blend were calculated on the basis of linearized Cahn‐Hilliard‐Cook theory. The kinetic results showed that LLPS of PMMI/PVDF blends followed the spinodal decomposition (SD) mechanism. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1923–1931, 2008
Reliability of performance‐based measures in people awaiting joint replacement surgery of the hip or knee
Authors: Gill Stephen , McBurney Helen 
Published: August 2008

AbstractBackground and Purpose. Understanding the reliability of selected measurement tools is a prerequisite to understanding the effects of clinical interventions. The aim of this investigation was to determine the reliability of the 50‐Foot Timed Walk (50 FTW) and 30‐second Chair Stand Test (30 CST) in subjects awaiting joint replacement surgery of the hip or knee. Methods. Eighty‐two subjects participating in a 6‐week exercise programme were assessed at baseline, 7 weeks and 15 weeks. Four trials of the 50 FTW and two trials of the 30 CST were completed at each assessment. Eleven trained assessors completed the assessments. Results. Intra‐class correlations were consistently high for the 50 FTW and 30 CST at all assessments. At the baseline assessment, trial 1 was found to be significantly different from subsequent trials for both the 50 FTW and 30 CST. This effect was not evident at the 7‐week and 15‐week assessments. At the baseline assessment, scores for the 50 FTW became stable after the first trial. Estimates of minimum detectable change indicated that participants needed to change by more than 3.08 seconds and 1.64 stands to be 90% confident that a real change had occurred for the 50 FTW and 30 CST, respectively. Conclusion. The 50 FTW and 30 CST can be reliable measures of physical performance. However, because we found a practice effect at the baseline assessment, a practice trial should be allowed before data collection begins. Because only two trials of the 30 CST were completed, further research is required to confirm whether scores at the initial assessment become stable on repeated testing. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of non‐selective non‐steroidal anti‐inflammatory drugs on the aggressiveness of prostate cancer
Authors: Stock David C. , Groome Patti A. , Siemens D. Robert , Rohland Susan L. , Song Zhi 
Published: August 2008

AbstractBACKGROUNDInflammatory mediators have a role in the initiation and progression of prostate cancer. Observed anti‐cancer effects of non‐steroidal anti‐inflammatory drugs (NSAIDs) have consisted largely of those that inhibit inflammatory mechanisms thought to promote an aggressive disease phenotype. Epidemiologic studies have supported a chemopreventive effect but there is little research on a possible protective role against prostate cancer aggressiveness and progression to advanced disease.METHODSWe conducted a population‐based exploratory study, using cross‐sectional and case‐cohort approaches to assess, the effect of NSAIDs on indicators of prostate cancer aggressiveness. The study population consisted of 1,619 randomly selected patients with a further over‐sampling of 453 prostate cancer mortality cases. All had been curatively treated by radical prostatectomy or external‐beam radiotherapy and were sampled using the Ontario Cancer Registry. Aggressiveness of disease at diagnosis, represented by Gleason score, and risk of prostate cancer death were compared across NSAID exposure groups.RESULTSThe adjusted odds ratio (OR) of a total Gleason score of 8–10 versus 2–6 indicated a non‐significant protective effect of NSAIDs (OR: 0.74, 95% CI: 0.47–1.17). We did not observe an association with risk of prostate cancer death overall (HR: 1.03, 95% CI: 0.79–1.34), but a secondary analysis indicated that NSAID users surviving five years may be protected from early prostate cancer death (HR: 0.54, 95% CI: 0.26–1.13).CONCLUSIONAlthough estimates were not statistically significant, this exploratory study indicates a possible negative association between NSAID use and disease aggressiveness. Larger investigations with more precise exposure measurements are recommended. Prostate 68: 1655–1665, 2008. © 2008 Wiley‐Liss, Inc.
Pore growth on n ‐InP in liquid ammonia: electrode potential and morphology evolution
Authors: Eb A. , Gonçalves A.‐M. , Santinacci L. , Mathieu C. , Etcheberry A. 
Published: August 2008

AbstractIn this paper we report the pore formation onto n ‐InP (100) in acidic liquid ammonia at 223 K, by applying a constant current density of 2 mA·cm–2. The evolution of the electrode potential and the pore morphology has been investigated in this uncommon non‐aqueous medium. This solvent provides true water free and oxygen free conditions. Specific and reproducible electrochemical behaviour have been obtained. An original evolution of the porous structure has been observed by scanning electron microscopy. Tortuous current line oriented pores are formed. Pores are organized in hemispherical depressions and a multilayered structure is also evidenced. A three distinguished steps evolution has been established. In the first step, an insoluble passive layer is formed on surface, followed by the nucleation of the porous layer. The second phase corresponds to the formation of the first porous layer; while the third stage corresponds to the periodic lift‐off of the porous layer constituting thus a multilayered structure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Neuronal dopamine transporter activity, density and methamphetamine inhibition are differentially altered in the nucleus accumbens and striatum with no changes in glycosylation in rats behaviorally sensitized to methamphetamine
Authors: Bjorklund Nicole L. , Sorg Barbara A. , Schenk James O. 
Published: August 2008

AbstractAnimals sensitized to methamphetamine (METH) have altered dopaminergic systems, including dopamine transporter (DAT) activity. We investigated the effects induced by a sensitizing dose (5 mg/kg, i.p. per day for 5 days) of METH on rat behavior, DA transport by the DAT, DAT density, and inhibition of DA transport by METH in both the nucleus accumbens and striatum. We further investigated possible changes to glycosylation of the DAT after METH sensitization. The dosing paradigm caused an increased stereotyped response in rats treated with METH compared with saline controls. In animals treated with METH, DA transport velocities were increased by 6.4% in the nucleus accumbens and decreased by 21% in the striatum. Western blots demonstrated that DAT density was unchanged in the nucleus accumbens of METH‐treated animals, but striatal DAT density was decreased by 20%. Further studies investigating METH inhibition of DA transport found that in the nucleus accumbens of METH‐treated animals, the IC50was shifted to a larger value (from 0.81 to 1.45 μM). In the striatum, the IC50was decreased by 19% (from 1.00 to 0.81 μM) in METH‐treated animals. Studies using glycosidase treatments and Western blots revealed that glycosylation was effectively removed byN‐glycanase and neuraminidase, but notO‐glycosidase or α‐mannosidase. These studies also suggest that glycosylation was not altered in METH‐treated animals. This study demonstrates that in animals sensitized to METH, the DAT is differentially regulated in different areas of the brain important for drug abuse, and that DA transport changes induced by METH are not due to DAT density, but to changes in the kinetics of the DAT. Additionally, this study suggests that glycosylation may not play a role in DAT activity changes after METH exposure. Synapse 62:736–745, 2008. © 2008 Wiley‐Liss, Inc.