bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymmetric reduction of aromatic ketimines in the presence of helical polymer as catalyst
Authors: Terada Kayo , Masuda Toshio , Sanda Fumio 
Published: August 2009

AbstractNovel optically active ethynyl monomers were synthesized from L‐valine and N‐methyl‐L‐valine, and polymerized with a rhodium catalyst to provide the polymers with number‐average molecular weights over 200,000 in good yields. The CD and UV‐vis spectra of the polymers indicated that they took helical structures with predominantly one‐handed screw sense in solution. The polymers served as catalysts of asymmetric reduction of aromatic ketimines to afford optically active amines in moderate yields. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4971–4981, 2009
Low Temperature Growth of Photoactive Titania by Atmospheric Pressure Plasma
Authors: Hodgkinson John L. , Yates Heather M. , Sheel David W. 
Published: August 2009

AbstractAtmospheric pressure glow discharge plasma CVD was used to deposit thin films of titania at 200 °C using two different precursors. The resulting films were characterised using techniques including XPS, RBS and XRD. It was established that annealing at temperatures as low as 275 °C produced crystalline films that were photocatalytically active. When annealed at 300 °C the photoactivity was greater than that of commercially available “self‐cleaning” titania films. The effects of the different precursors, annealing times and temperatures on the crystallinity and photoactivity are discussed.magnified image
Titanium Nitriding by Microwave Atmospheric Pressure Plasma: Towards Single Crystal Synthesis
Authors: Cardoso R. P. , Arnoult G. , Belmonte Thierry , Henrion G. , Weber Sylvian 
Published: August 2009

AbstractHigh temperature titanium nitriding is achieved by plasmas sustained at atmospheric pressure in a microwave resonant cavity. TiN layers produced in the temperature range (1 475–1 980 K) present a grain orientation that is mainly defined by initial grain orientation of the titanium substrate. Coarsening pretreatments on the titanium samples before nitriding allows the synthesis of a strongly oriented TiN layer. The TiN + α‐Ti layer thickness reaches about 116 µm after a 1 h treatment at 1 760 K. For these treatment times, the bulk material is not totally transformed into TiN, but this is a first step towards the synthesis of single crystals of TiN from commercial‐grade pure titanium.
Microplasma Stamps for Area‐Selective Modification of Polymer Surfaces
Authors: Lucas Nina , Franke Raimo , Hinze Alena , Klages Claus‐Peter , Frank Ronald , Büttgenbach Stephanus 
Published: August 2009

AbstractMicroplasma stamps based upon the principle of dielectric barrier discharges are applied to a new type of area‐selective surface modification process at atmospheric pressure. This process integrates the surface treatment and lateral microstructuring within one process step. For this purpose, the plasma is ignited in cavities which are formed temporarily by compressing the microplasma stamp and the substrate to be treated. In this work, we investigate the influence of the cavity design and the ignition conditions on the surface treatment. Furthermore, peptide synthesis on area‐selectively treated poly(propylene) surfaces is presented as an application.
Influence of Atmospheric Plasma Source and Gas Composition on the Properties of Deposited Siloxane Coatings
Authors: Dowling Denis P. , Ramamoorthy Amsarani , Rahman Mahfujur , Mooney Damian A. , MacElroy J. M. Don 
Published: August 2009

AbstractSiloxane coatings were deposited using two different atmospheric plasma systems namely a reel‐to‐reel atmospheric plasma liquid deposition system called Labline™ and an atmospheric plasma jet system called PlasmaStream™. Both systems combine an atmospheric plasma, with the use of liquid precursors. The influence of the plasma source and processing conditions on the deposited coating properties were studied. The coatings were deposited onto Vycor glass and silicon wafer substrates from a liquid tetraethyl orthosilicate (TEOS) precursor which was nebulized into both He and He/O2 plasmas. Higher film growth rates were obtained using the plasma jet system; however, the reel‐to‐reel system facilitated the larger area coating of webs. The thickness (spectroscopic ellipsometry measurements) and water contact angle profile of the films deposited using the jet system on silicon wafer substrates in static mode were investigated. Amongst the other coatings characterization techniques used to evaluate the deposited coatings were optical profilometry, XPS, SEM, and AFM. The formation of particulates due to excess gas‐phase reactions during the atmospheric plasma deposition of coatings has been widely reported. In this study, larger number of particulates were observed under the conditions of higher plasma power, with the addition of O2 into the He plasma and also at low TEOS flow rates. The introduction of N2 into the He/O2 plasma, during the deposition of siloxane coatings led to a significant reduction in the number of particulates generated for both plasma sources. Nitrogen gas flow rate was varied systematically and a correlation was obtained on the influence of the flow rate of this gas on surface roughness and particulate formation.
Tribological Performance of CrAlSiN Coatings at High Temperatures
Authors: Polcar Tomas , Vitu Tomas , Sondor Jozef , Cavaleiro Albano 
Published: August 2009

AbstractChromium aluminum nitride (CrAlN) coatings produced by PVD are routinely deposited on tools and tested as components for machining and forming applications. However, the addition of a doping element, such as Si, can further improve the properties of such coatings. In this study, CrAlN and CrAlSiN coatings with different Cr/Al ratio were prepared on WC substrates by low cathodic arc deposition and their structure and tribological properties analyzed in situ at high temperatures. In spite of excellent thermal stability and oxidation resistance, the hot‐sliding tests showed unsatisfactory coating behavior.
Optical Emission Spectroscopy of Argon–Fluorocarbon–Oxygen Fed Atmospheric Pressure Dielectric Barrier Discharges
Authors: Fanelli Fiorenza 
Published: August 2009

AbstractAtmospheric pressure filamentary dielectric barrier discharges (FDBDs) fed with argon, a fluorocarbon compound (i.e. CF4, C3F8, C3F6 and c‐C4F8) and O2 were investigated by optical emission spectroscopy (OES). The UV–Vis spectra of the plasma in argon–fluorocarbon mixtures are characterized by narrow signals from Ar atoms, CF2 and CF fragments and by two continua due to CF and CF3. O2 addition to the feed gas reduces the emissions of fluorocarbon fragments and results in the appearance of an intense narrow emission at 193 nm and of a broad continuum centred at 290 nm ascribed to ArF and Ar2F excimers, respectively. Any signal from F atoms was not detected under the experimental conditions investigated even though the plasma contains F atoms since the dry etching of silicon substrates, a typical process driven by F atoms, was observed. Some possible explanations of this phenomenon are presented.magnified image
Rituximab (B‐cell depleting antibody) associated lung injury (RALI): A pediatric case and systematic review of the literature
Authors: Bitzan Martin , Anselmo Mark , Carpineta Lucy 
Published: August 2009

AbstractIntroductionPulmonary toxicity of delayed onset is a rare complication of B‐lymphocyte depleting antibody therapy and has been almost exclusively reported in older patients with B‐cell malignancies.AimsTo describe a pediatric patient with rituximab‐associated lung injury (RALI), to systematically analyze previous reports of pulmonary complications, and to summarize common clinico‐pathological features, treatment, and outcome.ResultsA teenage boy with focal segmental glomerulosclerosis (FSGS) presented with progressive dyspnea, fever, hypoxemia and fatigue 18 days after the completion of a second course of rituximab infusions for calcineurin inhibitor‐dependent nephrotic syndrome. Respiratory symptoms started while he received high‐dose prednisone for persistent proteinuria. Bilateral, diffuse ground‐glass infiltrates corresponded to the presence of inflammatory cells in the bronchioalveolar lavage fluid. Empiric antibiotic treatment including clarithromycin was given, but the microbiological work‐up remained negative. Serum IgE, C3, and C4 concentrations were normal. He recovered within 3 weeks after onset.We systematically reviewed 23 reports describing 30 additional cases of rituximab‐associated lung disease. Twenty eight patients had received rituximab for B‐cell malignancies, one for graft‐versus‐host disease and one for immune thrombocytopenia. Median age was 64 years (interquartile range [IQR] 58–69 years). Seventy one percent received concomitant chemotherapy. Time to onset from the last rituximab dose was 14 days (IQR 11–22 days). Eleven of 31 patients required mechanical ventilation, and 9 died (29%). Ventilation was a significant predictor of fatal outcome (odds ratio 46.7; confidence interval 9.5–229.9). High dose glucocorticoid therapy did not improve survival or prevent severe lung disease or death.ConclusionsWith the expanding use of rituximab for novel indications, additional cases of RALI affecting younger age groups are expected to emerge. Mechanical ventilation predicts poor outcome. Glucocorticoids may not be protective. Pediatr Pulmonol. 2009; 44:922–934. © 2009 Wiley‐Liss, Inc.
Effects of the 5 alpha‐reductase inhibitor dutasteride on gene expression in prostate cancer xenografts
Authors: Schmidt Lucy J. , Regan Kevin M. , Anderson S. Keith , Sun Zhifu , Ballman Karla V. , Tindall Donald J. 
Published: August 2009

AbstractBACKGROUNDIn the prostate, androgens play a crucial role in normal and cancerous growth; hence the androgenic pathway has become a target of therapeutic intervention. Dutasteride is a 5 alpha‐reductase (5AR) inhibitor currently being evaluated both for chemoprevention and treatment of prostate cancer. Dutasteride inhibits both 5AR I and II enzymes, effectively blocking conversion of testosterone to dihydrotestosterone (DHT) in the prostate. This greatly reduces the amount of the active ligand DHT available for binding to the androgen receptor (AR) and stimulating proliferation, making this a good candidate for chemoprevention of prostate cancer. In this study, we sought to determine how dutasteride is functioning at the molecular level, using a prostate cancer xenograft model.METHODSAndrogen‐responsive LuCaP 35 xenograft tumors were grown in Balb/c mice. Subcutaneously implanted time‐release pellets were used for drug delivery. Microarray analysis was performed using the Affymetrix HG‐U133Av2 platform to examine changes in gene expression in tumors following dutasteride treatment.RESULTSDutasteride significantly reduced tumor growth in LuCaP 35 xenografts by affecting genes involved in apoptotic, cytoskeletal remodeling, and cell cycle pathways among others. Notably, genes in the Rho GTPase signaling pathway, shown to be important in androgen‐deprivation conditions, were significantly up‐regulated.CONCLUSIONWe have identified multiple pathways outside of the androgenic pathway in prostate cancer xenografts affected by treatment with dutasteride. These findings provide insights into the function of dutasteride within the tumor microenvironment, potentially allowing for development of agents that can be used in combination with this drug to further enhance its effectiveness. Prostate 69: 1730–1743, 2009. © 2009 Wiley‐Liss, Inc.
Singlet methylene insertion into polar OH and NH bonds of water and ammonia—Ab initio and DFT study
Authors: Ramasami K. , Ramalingam M. , Venuvanalingam P. , Jaccob M. 
Published: August 2009

AbstractCorrelated ab initio molecular orbital, DFT, QCISD, G3MP2, and QCISD(T) calculations have been used to investigate the geometries, energetics, and mechanisms governing the insertion reactions of 1CH2 into OH and NH bonds of water and ammonia, respectively, in gas phase adopting 6‐311++g(d, p) basis set. It is found that 1CH2 reacts with water and ammonia to produce the ylide‐like intermediates H2COH2 and H2CNH3, which in turn undergo 1,2‐hydrogen shift to produce methanol and methylamine, respectively. Results obtained indicate that in the gas phase, the ylides and the transition states are located below the reactants' energy levels. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
DFT investigation of MoS2 nanoclusters used as desulfurization catalysts
Authors: McBride Kendra L. , Head John D. 
Published: August 2009

AbstractSupported single‐layer MoS2 is a well‐established catalyst used by the petroleum industry to remove sulfur from fossil fuels. It is believed that the catalytic activity occurs at the edge of the MoS2 nanoparticles. Recently, atomic‐scale images of MoS2 nanoclusters under catalytic working conditions have been obtained with scanning tunneling microscopy (STM). These images show that certain triangular‐shaped “magic clusters” are formed, where the triangular shape is attributed to stabilization from excess sulfur at the cluster edges. Much of the recent theoretical rationalization of the MoS2 cluster structures has been formulated by using plane‐wave DFT calculations. However, the clusters observed in the recent STM images are small enough that their structures and properties can be evaluated using direct space DFT calculations. We present the theoretically optimized structures obtained with DFT calculations for the series of Mo10Sx clusters with x = 12, 18, 24, 30, and 36. From consideration of their relative energies and simulated STM images, we find the cluster with the Mo10 core most likely being imaged in the STM experiments is the Mo‐edge cluster Mo10S24. This contrasts with the assignment to the S‐edge cluster Mo10S24 by the experimentalists and their suggestion that Mo‐edge clusters are less favored than S‐edge clusters when there are 21 or less Mo atoms. Furthermore, despite being able to build initial Mo10Sx structures with a high degree of symmetry, we find the fully optimized Mo10Sx clusters to have essentially no symmetry, and we discuss how this could be playing a role in the MoS2 catalytic activity. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Theoretical study on the effects of oxygen doping on the lithium ion conductive perovskite‐type manganese fluoride of KxBa(1−x)/2MnF3
Authors: Onishi Taku 
Published: August 2009

AbstractPreviously, we demonstrated that the lithium ion conduction in the perovskite‐type manganese fluoride is attributed to counter cation‐site vacancy mechanism. The divalent counter cation‐doped KxBa(1−x)/2MnF3 was theoretically predicted as the lithium ion conductor in the perovskite‐type manganese fluoride. In this study, we considered the oxygen doping for KxBa(1−x)/2MnF3 to realize the higher lithium ion conductivity. It is because lithium ion forms the stronger ionic bond with the doped oxygen anion. The hybrid‐DFT calculations were performed to investigate the lithium ion conduction in the oxygen‐doped KxBa(1−x)/2MnF3. The calculation results were discussed from the viewpoints of the potential energy curve, electron densities, and charge and spin densities. The effect of the lithium ion fluctuation was also discussed by calculating the ratio of the diffusion coefficients. Finally, we theoretically predicted the ideal oxygen‐doped structure for KxBa(1−x)/2MnF3. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Photoemission into water adsorbed on metals: Probing dissociative electron transfer using theory
Authors: Zhang Yu , Whitten J. L. 
Published: August 2009

AbstractThe photoinduced dissociation of water adsorbed on a silver nanoparticle is explored using theory to probe reaction pathways that produce hydrogen. Ab initio configuration theory is used to describe the systems. A formulation that allows excited electronic states embedded in a near continuum of lower energy states to be calculated accurately is described. Electron attachment of a photoemitted electron to adsorbed water can lead to the formation of H2 at a very low energy barrier with oxygen remaining on the Ag surface. A large energy barrier to form H2 plus adsorbed O is found for the ground state. The excited state has a much smaller barrier to OH stretch; however, to dissociate, the system must cross over from the excited state to the ground state potential energy surface. The cross over point is near the transition state for a ground state process. A characteristic feature of the excited state potential curve is an increase in energy in the early stages of OH stretch as the charge transfer state evolves from a state with considerable Rydberg character to one that has a typical OH antibonding molecular orbital. Another pathway releases a H atom leaving OH on the surface. Effects due to doping of a Ag nanoparticle with a K electron donor atom are compared with those caused by a Fermi level shift due to an applied potential. Results are also reported for electron transfer to a solvated lithium ion, Li(H2O), near the surface of a silver particle. A steering mechanism is found that involves the interaction of a hydridic hydrogen formed after electron transfer with an acidic hydrogen of a second solvated water molecule. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Experimental determination of a Viviparus contectus thermometry equation
Authors: Bugler Melanie J. , Grimes Stephen T. , Leng Melanie J. , Rundle Simon D. , Price Gregory D. , Hooker Jerry J. , Collinson Margaret E. 
Published: August 2009

AbstractExperimental measurements of the 18O/16O isotope fractionation between the biogenic aragonite of Viviparus contectus (Gastropoda) and its host freshwater were undertaken to generate a species‐specific thermometry equation. The temperature dependence of the fractionation factor and the relationship between Δδ18O (δ18Ocarb. – δ18Owater) and temperature were calculated from specimens maintained under laboratory and field (collection and cage) conditions. The field specimens were grown (Somerset, UK) between August 2007 and August 2008, with water samples and temperature measurements taken monthly. Specimens grown in the laboratory experiment were maintained under constant temperatures (15°C, 20°C and 25°C) with water samples collected weekly. Application of a linear regression to the datasets indicated that the gradients of all three experiments were within experimental error of each other (±2 times the standard error); therefore, a combined (laboratory and field data) correlation could be applied. The relationship between Δδ18O (δ18Ocarb. – δ18Owater) and temperature (T) for this combined dataset is given by:

(T is in °C, δ18Ocarb. is with respect to Vienna Pee Dee Belemnite (VPDB) and δ18Owater is with respect to Vienna Standard Mean Ocean Water (VSMOW). Quoted errors are 2 times standard error).Comparisons made with existing aragonitic thermometry equations reveal that the linear regression for the combined Viviparus contectus equation is within 2 times the standard error of previously reported aragonitic thermometry equations. This suggests there are no species‐specific vital effects for Viviparus contectus. Seasonal δ18Ocarb. profiles from specimens retrieved from the field cage experiment indicate that during shell secretion the δ18Ocarb. of the shell carbonate is not influenced by size, sex or whether females contained eggs or juveniles. Copyright © 2009 John Wiley & Sons, Ltd.
Two‐injection workflow for a liquid chromatography/LTQ‐Orbitrap system to completein vivobiotransformation characterization: demonstration with buspirone metabolite identification
Authors: Li Austin C. , Ding Jie , Jiang Xiangyu , Denissen Jon 
Published: August 2009

AbstractThe relatively high background matrix inin vivosamples typically poses difficulties in drug metabolite identification, and causes repeated analytical runs on unit resolution liquid chromatography/mass spectrometry (LC/MS) systems before the completion of biotransformation characterization. Ballpark parameter settings for the LTQ‐Orbitrap are reported herein that enable completein vivometabolite identification within two HPLC/MS injections on the hybrid LTQ‐Orbitrap data collection system. By setting the FT survey full scan at 60K resolution to trigger five dependent LTQ MS2scans, and proper parameters of Repeat Duration, Exclusion Duration and Repeat Count for the first run (exploratory), the Orbitrap achieved the optimal parallel data acquisition capability and collected maximum number of product ion scans. Biotransformation knowledge based prediction played the key role in exact mass ion extraction and multiple mass defect filtration when the initial data was processed. Meanwhile, product ion extraction and neutral loss extraction of the initial dependent data provided additional bonus in identifying metabolites. With updated parent mass list and the data‐dependent setting to let only the ions on the parent mass list trigger dependent scans, the second run (confirmatory) ensures that all precursor ions of identified metabolites trigger not only dependent product ion scans, but also at or close to the highest concentration of the eluted metabolite peaks. This workflow has been developed for metabolite identification ofin vivoor ADME studies, of which the samples typically contain a high level of complex matrix. However, due to the proprietary nature of thein vivostudies, this workflow is presented herein within vitrobuspirone sample incubated with human liver microsomes (HLM). The major HLM‐mediated biotransformation on buspirone was identified as oxidation or hydroxylation since five mono‐ (+16 Da), seven di‐ (+32 Da) and at least three tri‐oxygenated (+48 Da) metabolites were identified. Besides the metabolites 1‐pyrimidinylpiperazine (1‐PP) and hydroxylated 1‐PP that formed by N‐dealkylation, a new metabolite M308 was identified as the result of a second N‐dealkylation of the pyrimidine unit. Two new metabolites containing the 8‐butyl‐8‐azaspiro[4,5]decane‐7,9‐dione partial structure, M240 and M254, were also identified that were formed apparently due to the first N‐dealkylation of the 1‐PP moiety. Copyright © 2009 John Wiley & Sons, Ltd.
Effects of substrate surfaces in matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Togashi Hisashi , Kobayashi Yoshinori 
Published: August 2009

AbstractFor matrix‐assisted laser desorption/ionization (MALDI) mass spectra, undesirable ion contamination can occur due to the direct laser excitation of substrate materials (i.e., laser desorption/ionization (LDI)) if the samples do not completely cover the substrate surfaces. In this study, comparison is made of LDI processes on substrates of indium and silver, which easily emit their own ions upon laser irradiation, and conventional materials, stainless steel and gold. A simultaneous decrease of ion intensities with the number of laser pulses is observed as a common feature. By the application of an indium substrate to the MALDI mass spectrometry of alkali salts and alkylammonium salts mixed with matrices, 2,5‐dihydroxybenzoic acid (DHB) or N‐(4‐methoxybenzylidene)‐4‐butylaniline (MBBA), the mixing of LDI processes can be detected by the presence of indium ions in the mass spectra. This method has also been found to be useful for investigating the intrinsic properties of the MALDI matrices: DHB samples show an increase in the abundance of fragment ions of matrix molecules and cesium ions with the number of laser pulses irradiating the same sample spot; MBBA samples reveal a decrease in the level of background noise with an increase in the thickness of the sample layer. Copyright © 2009 John Wiley & Sons, Ltd.