bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of a cylindrical ion trap supplied by a periodic impulsional potential
Authors: Seddighi Chaharborj S. , Sadat Kiai S. M. 
Published: July 2010

AbstractThis article reports on some theoretical studies concerning the impulsional mode of a cylindrical ion trap (CIT) supplied with a periodic impulsional radio frequency (rf) voltage of the form VaccosΩt/(1 − kcos2Ωt) with 0 ≤ k < 1. The performance characteristics of CIT impulsional mode, for the twelve stability regions, were computed using fifth order Runge‐Kutta method and were compared to the classical sinusoidal mode k = 0. Also, the results show that, for the same equivalent operating point in two stability diagrams (having the same βz) the associated modulated secular ion frequencies behavior are the same. Copyright © 2010 John Wiley & Sons, Ltd.
Fatty Acid Derived Monomers and Related Polymers Via Thiol‐ene (Click) Additions
Authors: Türünç Oĝuz , Meier Michael A. R. 
Published: July 2010

AbstractThiol‐ene additions of methyl 10‐undecenoate, a castor oil derived renewable platform chemical, were studied with the goal of preparing a set of renewable monomers. Good to excellent yields were obtained for these solvent and initiator free thiol‐ene additions. The resulting monomers were then polymerized using TBD as a catalyst, to linear as well as hyperbranched polyesters that also contain thio‐ether linkages. All thus prepared polymers were fully characterized (NMR, GPC, DSC, and TGA) and the results of these investigations will be discussed within this contribution. The thermal analysis of these polymers revealed melting points in the range from 50 to 71 °C. Moreover, no significant weight loss was observed below 300 °C.magnified image
Targeted projection NMR spectroscopy for unambiguous metabolic profiling of complex mixtures
Authors: Pontoizeau Clément , Herrmann Torsten , Toulhoat Pierre , Elena‐Herrmann Bénédicte , Emsley Lyndon 
Published: July 2010

AbstractUnambiguous identification of individual metabolites present in complex mixtures such as biofluids constitutes a crucial prerequisite for quantitative metabolomics, toward better understanding of biochemical processes in living systems. Increasing the dimensionality of a given NMR correlation experiment is the natural solution for resolving spectral overlap. However, in the context of metabolites, natural abundance acquisition of 1H and 13C NMR data virtually excludes the use of higher dimensional NMR experiments (3D, 4D, etc.) that would require unrealistically long acquisition times. Here, we introduce projection NMR techniques for studies of complex mixtures, and we show how discrete sets of projection spectra from higher dimensional NMR experiments are obtained in a reasonable time frame, in order to capture essential information necessary to resolve assignment ambiguities caused by signal overlap in conventional 2D NMR spectra. We determine optimal projection angles where given metabolite resonances will have the least overlap, to obtain distinct metabolite assignment in complex mixtures. The method is demonstrated for a model mixture composition made of ornithine, putrescine and arginine for which acquisition of a single 2D projection of a 3D 1H–13C TOCSY‐HSQC spectrum allows to disentangle the metabolite signals and to access to complete profiling of this model mixture in the targeted 2D projection plane. Copyright © 2010 John Wiley & Sons, Ltd.
Real‐time visualization of muscle stiffness distribution with ultrasound shear wave imaging during muscle contraction
Authors: Shinohara Minoru , Sabra Karim , Gennisson Jean‐Luc , Fink Mathias , Tanter Mickaél 
Published: July 2010

AbstractA stand‐alone ultrasound shear wave imaging technology has been developed to quantify and visualize Young's modulus distribution by remotely applying ultrasound radiation force and tracking the resulting microvibrations in soft tissues with ultrafast ultrasound imaging. We report the first preliminary data that detected the distribution of local muscle stiffness within and between resting and contracting muscles at different muscle lengths with this technology. This technique may assist clinicians in characterizing muscle injuries or neuromuscular disorders. Muscle Nerve, 2010
New implementation of radial basis functions for solving Burgers‐Fisher equation
Authors: Tatari Mehdi , Sepehrian Behnam , Alibakhshi Maryam 
Published: July 2010

AbstractIn this article, we consider the problem of solving Burgers‐Fisher equation. The approximate solution is found using the radial basis functions collocation method. Also for solving of the resulted nonlinear system of equations, we proposed a predictor corrector method based on the fixed point iterations. The numerical tests show that this method is accurate and efficient for finding a closed form approximation of the solution of nonlinear partial differential equations. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 248–262, 2012
Brachmann–de Lange syndrome: definition of prenatal sonographic features to facilitate definitive prenatal diagnosis
Authors: Pajkrt E. , Griffin D. R. , Chitty L. S. 
Published: July 2010

AbstractObjectiveThe objective was to improve the prenatal diagnosis of Brachmann–de Lange syndrome (BDLS) by defining the sonographic criteria.MethodsRetrospective review of Fetal Medicine Unit (FMU) notes from 1998 to 2009 to identify all cases seen with a final diagnosis of BDLS. Literature review undertaken to ascertain all cases where sonographic features of BDLS had been described. Information was pooled to define the most common features.ResultsSeven cases were identified from review of FMU records. The diagnosis was suspected prenatally in four of the seven. All had asymmetrical forearm defects with oligodactyly/polydactyly, five had intrauterine growth restriction (IUGR) and five had abnormal facial features including micrognathia and/or a long overhanging philtrum. A further 28 cases were identified in the literature, but the diagnosis was only suspected prenatally in nine. Overall the most common feature was IUGR (80%); upper limb anomalies were detected in nearly half of cases. Other common features included facial anomalies (40%), diaphragmatic hernia (34%), increased nuchal translucency/fold (37%) and cardiac anomalies (14%).ConclusionsIdentification of asymmetrical oligodactyly with or without forearm anomalies associated with microcephaly and/or IUGR or diaphragmatic hernia are findings that should arouse suspicion of BDLS, although definitive diagnosis at present would have to await delivery in the majority of cases. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation of the chitosan containing nanofibers by electrospinning chitosan–gelatin complexes
Authors: Haider Sajjad , Al‐Masry Waheed A. , Bukhari Nausheen , Javid Muhammad 
Published: July 2010

AbstractElectrospinning is an interesting technique, which provides a facile and an effective mean in producing nonwoven fibrous materials; however, for producing nanofibers, investigation of the electrospinning conditions is very important. In this study, chitosan, gelatin, and their polyelectrolyte complexes (PECs) were electrospun to prepare nonwoven nanofibrous mats. The concentrations of chitosan and gelatin solutions and electric field (kV/cm) were optimized. The solutions were then blended in different ratios (0–100%) to get electrospun nanofibrous mats. Solution concentration and electric field showed pronounced effect on the electrospinnability and fiber diameter of these systems. Mostly large beads coexisted with the fibers were observed for chitosan at 1 wt% solution concentration, which then showed good electrospinnability at 2 wt% (nanofiber diameter was 145 and 122 nm at 15 and 20 kV/10 cm, respectively), whereas gelatin showed no electrospinnability below 15 wt% solution concentration and a homogenous fibers network at 15 wt% (149 nm at 20 kV/10 cm). The morphology and diameter of chitosan–gelatin PEC nanofibers varied with the chitosan/gelatin ratio. The crystallinity of chitosan was also observed to reduce with electrospinning and addition of gelatin. POLYM. ENG. SCI. 50:1887–1893, 2010. © 2010 Society of Plastics Engineers
Development and characterization of solid and porous polylactide‐multiwall carbon nanotube composites
Authors: Rizvi Reza , Khan Omer , Naguib Hani E. 
Published: July 2010

AbstractThis article describes the fabrication of solid and porous polylactide (PLA)‐multiwall carbon nanotube (MWNT) composites prepared using melt blending and subsequent batch processing of porous structures. The morphology and thermal, rheological and electrical properties of the PLA‐MWNT composites prepared with MWNT concentrations of 0, 0.5, 1, 2, and 5 wt% were characterized. The composite structure consisted of identifiable regions of MWNT aggregation and MWNT dispersion. Increasing MWNT content was found to increase the thermal stability and crystallization kinetics of PLA. The addition of MWNT to PLA significantly increased the melt viscosity and electrical conductivity of the composites. Based on rheological and electrical measurements, a continuous MWNT network structure in PLA was found to form when the concentration of MWNT is increased from 0.5 wt% (0.33 vol%) to 1 wt% (0.66 vol%). As many current day applications of polymers and polymer composites require lightweight and low‐density materials, porous PLA‐MWNT composites were fabricated from a batch porous structure processing technique. Porous PLA‐MWNT composites containing 2 and 5 wt% MWNT had lower relative densities, which is attributed to the higher viscosity of the composites suppressing collapse of the porous structure during processing. POLYM. ENG. SCI., 2011. © 2010 Society of Plastics Engineers
A well‐characterised peak identification list of MALDI MS profile peaks for human blood serum
Authors: Tiss Ali , Smith Celia , Menon Usha , Jacobs Ian , Timms John F. , Cramer Rainer 
Published: July 2010

AbstractMALDI MS profiling, using easily available body fluids such as blood serum, has attracted considerable interest for its potential in clinical applications. Despite the numerous reports on MALDI MS profiling of human serum, there is only scarce information on the identity of the species making up these profiles, particularly in the mass range of larger peptides. Here, we provide a list of more than 90 entries of MALDI MS profile peak identities up to 10 kDa obtained from human blood serum. Various modifications such as phosphorylation were detected among the peptide identifications. The overlap with the few other MALDI MS peak lists published so far was found to be limited and hence our list significantly extends the number of identified peaks commonly found in MALDI MS profiling of human blood serum.
Differential effect of YidC depletion on the membrane proteome of Escherichia coli under aerobic and anaerobic growth conditions
Authors: Price Claire E. , Otto Andreas , Fusetti Fabrizia , Becher Dörte , Hecker Michael , Driessen Arnold J. M. 
Published: July 2010

AbstractYidC of Escherichia coli belongs to the evolutionarily conserved Oxa1/Alb3/YidC family. Members of the family have all been implicated in membrane protein biogenesis of respiratory and energy transducing proteins. The number of proteins identified thus far to require YidC for their membrane biogenesis remains limited and the identification of new substrates may allow the elucidation of properties that define the YidC specificity. To this end we investigated changes in the membrane proteome of E. coli upon YidC depletion using metabolic labeling of proteins with 15N/14N combined with a MS‐centered proteomics approach and compared the effects of YidC depletion under aerobic and anaerobic growth conditions. We found that YidC depletion resulted in protein aggregation/misfolding in the cytoplasm as well as in the inner membrane of E. coli. A dramatic increase was observed in the chaperone‐mediated stress response upon YidC depletion and this response was limited to aerobically grown cells. A number of transporter proteins were identified as possible candidates for the YidC‐dependent insertion and/or folding pathway. These included the small metal ion transporter CorA, numerous ABC transporters, as well as the MFS transporters KgtP and ProP, providing a new subset of proteins potentially requiring YidC for membrane biogenesis.
Conformational analysis of 3‐methyl‐3‐silathiane and 3‐fluoro‐3‐methyl‐3‐silathiane
Authors: Kirpichenko Svetlana V. , Kleinpeter Erich , Ushakov Igor A. , Shainyan Bagrat A. 
Published: July 2010

AbstractThe conformational equilibria of 3‐methyl‐3‐silathiane 5, 3‐fluoro‐3‐methyl‐3‐silathiane 6 and 1‐fluoro‐1‐methyl‐1‐silacyclohexane 7 have been studied using low temperature 13C NMR spectroscopy and theoretical calculations. The conformer ratio at 103 K was measured to be about 5ax:5eq = 15:85, 6ax:6eq = 50:50 and 7ax:7eq = 25:75. The equatorial preference of the methyl group in 5 (0.35 kcal mol−1) is much less than in 3‐methylthiane 9 (1.40 kcal mol−1) but somewhat greater than in 1‐methyl‐1‐silacyclohexane 1 (0.23 kcal mol−1). Compounds 5–7 have low barriers to ring inversion: 5.65 (ax → eq) and 6.0 (eq → ax) kcal mol−1 (5), 4.6 (6), 5.1 (Meax → Meeq) and 5.4 (Meeq → Meax) kcal mol−1 (7). Steric effects cannot explain the observed conformational preferences, like equal population of the two conformers of 6, or different conformer ratio for 5 and 7. Actually, by employing the NBO analysis, in particular, considering the second order perturbation energies, vicinal stereoelectronic interactions between the Si–X and adjacent C–H, C–S, and C–C bonds proved responsible. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of titanocene dichloride derivatives on prostate cancer cells, specifically DNA damage‐induced apoptosis
Authors: Cuffe Sandra , Dowling Catherine M. , Claffey James , Pampillón Clara , Hogan Megan , Fitzpatrick John M. , Carty Michael P. , Tacke Matthias , Watson R. William G. 
Published: July 2010

AbstractBACKGROUNDWhile locally advanced prostate cancer is initially treatable with androgen ablation, eventually cells develop a castrate‐resistant phenotype. Currently, there are no effective treatments for this form of the disease with Docetaxel only providing a small survival advantage. In this study, the effects of novel derivatives of titanocene dichloride on prostate cancer cell lines has been investigated.METHODSCellular effects were assessed using the crystal violet assay and the clonogenic survival assay. Cell cycle and apoptosis were assessed by propidium iodide staining. DNA damage was analyzed by comet assay and Western analysis. DNA damage response inhibition was achieved by pre‐incubation with an ATM/ATR inhibitor; CGK733 and DNA‐PK inhibitor; DMNB.RESULTSThese analogs caused a reduction in cell number. In particular titanocene Y and C had significant effects in all cell lines. A reduction in clonogenic survival was found in response to titanocene Y in three cell lines while the PC‐3 cells exhibited increased resistance.Further analysis showed no effect on cell cycle however, the analogs were found to induce apoptosis in a dose‐dependent manner in all cell lines. These analogs associate with DNA, induce DNA damage and a differential damage response. Inhibition of key regulators of this DNA damage response sensitized the PC‐3 cell line to titanocene‐induced apoptosis and significantly reduced the clonogenic capacity of the cells.CONCLUSIONThese results demonstrate the mechanism of action of these novel titanocene dichloride analogs and their potential use in castrate‐independent advanced prostate cancer. Prostate 71: 111–124, 2011. © 2010 Wiley‐Liss, Inc.
Candidacidal mechanism of a Leu/Lys‐rich α‐helical amphipathic model antimicrobial peptide and its diastereomer composed of D,L‐amino acids
Authors: Wang Peng , Nan Yong Hai , Shin Song Yub 
Published: July 2010

AbstractWe investigated the mechanism of candidacidal action of a Lys/Leu‐rich α‐helical model antimicrobial peptide (K9L8W) and its diastereomeric peptide (D9‐K9L8W) composed of D,L‐amino acids. K9L8W killed completely Candida albicans within 30 min, but D9‐K9L8W killed only 72% of C. albicans even after 100 min. Tryptophan fluorescence spectroscopy indicated that the fungal cell selectivity of D9‐K9L8W is closely correlated with a selective interaction with the negatively charged PC/PE/PI/ergosterol (5:2.5:2.5:1, w/w/w/w) phospholipids, which mimic the outer leaflet of the plasma membrane of C. albicans. K9L8W was able to induce almost 100% calcein leakage from PC/PE/PI/ergosterol (5:2.5:2.5:1, w/w/w/w) liposomes at a peptide:lipid molar ratio of 1:16, whereas D9‐K9L8W caused only 25% dye leakage even at a peptide:lipid molar ratio of 1:2. Confocal laser‐scanning microscopy revealed that FITC‐labeled D9‐K9L8W penetrated the cell wall and cell membrane and accumulated inside the cells, whereas FITC‐labeled K9L8W did not penetrate but associated with the membranes. Collectively, our results demonstrated that the candidacidal activity of K9L8 W and D9‐K9L8W may be due to the transmembrane pore/channel formation or perturbation of the fungal cytoplasmic membranes and the inhibition of intracellular functions, respectively. Finally, D9‐K9L8W with potent anti‐Candida activity but no hemolytic activity may be potentially a useful lead compound for the development of novel antifungal agents. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Resistive switching characteristics of TiN/MnO2/Pt memory devices
Authors: Yang Min Kyu , Park Jae‐Wan , Ko Tae Kuk , Lee Jeon‐kook 
Published: July 2010

AbstractBipolar resistive switching memory devices with a TiN/MnO2/Pt structure were investigated in a low power operation (250 μA/±0.6 V). The devices showed good endurance of 105 cycles at a 1 μs pulse and reliable data retention at both RT and 125 °C. Moreover, the benefits of a high device yield and potential multilevel storage make them promising devices in next generation nonvolatile memory applications. The cell area dependency suggests that the conducting mechanism in the low resistance states is due to the formation of locally conducting filaments. The results demonstrate the feasibility of high performance resistive switching memory devices based on transition metal oxides by using TiN as the top electrode. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Anxiolytic activity of a supercritical carbon dioxide extract of Souroubea sympetala (Marcgraviaceae)
Authors: Mullally Martha , Kramp Kari , Cayer Chris , Saleem Ammar , Ahmed Fida , McRae Calum , Baker John , Goulah Andrew , Otorola Marco , Sanchez Pablo , Garcia Mario , Poveda Luis , Merali Zul , Durst Tony , Trudeau Vance L. , Arnason John Thor 
Published: July 2010

AbstractThe purpose of this work was to develop an extraction technique to yield a betulinic acid‐(BA) enriched extract of the traditional anti‐anxiety plant Souroubea sympetala Gilg (Marcgraviaceae). Five extraction techniques were compared: supercritical carbon dioxide extraction (SCE), conventional solvent extraction with ethyl acetate (EtOAc), accelerated solvent extraction (ASE), ultrasonic assisted extraction (UAE) and soxhlet extraction (Sox). The EtOAc and SCE extraction methods resulted in BA‐enriched extracts, with BA concentrations of 6.78 ± 0.2 and 5.54 ± 0.2 mg/g extract, respectively, as determined by HPLC‐APCI‐MS. The bioactivity of the BA‐enriched extracts was compared in the elevated plus maze (EPM), a validated rodent anxiety behaviour assay. Rats orally administered a 75 mg/kg dose of SCE extract exhibited anxiolysis as compared with vehicle controls, with a 50% increase in the percent time spent in the open arms, a 73% increase in unprotected head dips and a 42% decrease in percent time spent in the closed arms. No significant differences were observed between the SCE and EtOAc extracts for these measures, but the animals dosed with SCE extract had significantly more unprotected head dips than those dosed with the EtOAc extract. The SCE extract demonstrated a dose‐response in the EPM, with a trend toward decreased anxiety at 25 mg/kg, and significant anxiolysis was only observed at 75 mg/kg dose. This study demonstrates that SCE can be used to generate a betulinic acid‐enriched extract with significant anxiolysis in vivo. Further, the study provides a scientific basis for the ethnobotanical use of this traditional medicine and a promising lead for a natural health product to treat anxiety. Copyright © 2010 John Wiley & Sons, Ltd.
Surface modification and characterization of phenanthroline nanofilms on carbon substrate
Authors: Oztekin Yasemin , Yazicigil Zafer , Solak Ali Osman , Ustundag Zafer , Kilic Zeynel , Bilge Selen 
Published: July 2010

AbstractModification of glassy carbon (GC) surfaces with phenanthroline derivatives (PDs) such as 5‐amino‐1,10‐phenanthroline (5AP) and 5,6‐diamino‐1,10‐phenanthroline (56DAP) is described in this study. Surface modification experiments were performed by cyclic voltammetry (CV) scanning from + 1.2 to + 2.7 V at scan rate of 100 mV/s applying 30 potential scans in acetonitrile (CH3CN) containing 1 mM PDs and 100 mM tetrabutylammoniumtetrafluoroborate (TBATFB). The presence of PDs on GC electrode was confirmed using CV, electrochemical impedance spectroscopy (EIS), contact angle measurements and ellipsometry and comparing with the results of bare GC electrode. A mechanism was proposed for the electrochemical modification of the GC electrode surface with PDs. The structure of the 5AP and 56DAP films was also discussed in the light of electrochemical and spectroscopic data. The complex‐forming ability of the modified surfaces against metal cations was investigated by square‐wave voltammetry (SWV). It was shown that surfaces having 1,10‐phenanthroline ligands with different functional groups were quite useful for the determination of transition metal ions. Copyright © 2010 John Wiley & Sons, Ltd.
Cesium retention during sputtering with low energy Cs+ and oxygen flooding
Authors: Berghmans B. , Rip J. , Vandervorst W. 
Published: July 2010

AbstractAccurate knowledge of the stationary Cs retention during Ultra Low Energy (ULE; < 150 eV) Cs+ sputtering (of semiconductor substrates) is the first step towards understanding the basics of SIMS. We have investigated the effect of oxygen on the retention capacity for cesium on silicon and germanium targets. The amount of cesium that is retained was directly measured using Inductively Coupled Plasma Mass Spectrometry (ICP‐MS). Even a very small partial pressure of oxygen (in the 10−9 to 10−8 mbar range) will tremendously increase the dose of cesium that is retained at the sample surface. Concurrent with this increased retention (due to Cs‐oxide formation) strong variations in the target sputtering yield and the ionization degree of silicon can be observed.These data combined support the model that the observed target sputtering yield is directly linked to the Cs‐surface coverage and that a cap layer containing a very high amount of Cs can be formed by the ion beam. The sensitivity to oxygen becomes stronger as the primary ion energy decreases, and implies that SIMS measurements with Cs aimed at a very high depth resolution will suffer from drastically reduced erosion rates due to the deposition process.1 Copyright © 2010 John Wiley & Sons, Ltd.