bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mild route to generate gaseous metal anions
Authors: Attygalle Athula B. , Axe Frank U. , Weisbecker Carl S. 
Published: February 2011

AbstractGaseous metal anions such as Na−, K−, Cs−, and Ag− can be generated at ambient temperatures by the collision‐induced dissociation of the anions of several dicarboxylic acid salts, including oxalate, maleate, fumarate, succinate, and glutamate salts. The formation of gaseous metal anions in this way is unprecedented because the metal is initially present in its cationic form. The mild process described here could facilitate novel applications of metal anions as selective reagents for gas‐phase ion‐molecule and ion‐ion reactions. Ab initio calculations were used to describe the dissociation process for anions of the oxalate salts. The formation of alkalides occurs via production of a metal‐carbon dioxide anion intermediate with a bidentate three‐center two‐electron bond to the metal. The metal atom acquires a partial negative charge in the intermediate structure. Copyright © 2011 John Wiley & Sons, Ltd.
Electron ionization mass spectra of alkylated sulfabenzamides
Authors: Todua Nino G. , Tretyakov Kirill V. , Borisov Roman S. , Zhilyaev Dmitry I. , Zaikin Vladimir G. , Stein Stephen E. , Mikaia Anzor I. 
Published: February 2011

AbstractMono‐, di‐ and trialkyl derivatives of 'sulfabenzamide' (N‐4‐aminophenylsulfonylbenzamide) have been prepared and their electron ionization (EI) mass spectra examined. It is found that the fragmentation of N‐alkylsulfabenzamides (alkyl = CH3 to n‐C5H11) proceeds via a very specific rearrangement process. The proposed mechanism involves an intermediate formation of distonic molecular ions, and the driving force for this process is the formation of stable N‐alkylphenylcyanide cations [R‐N+  CC6H5]. The findings are confirmed by exact mass measurements, tandem mass spectrometry (MS/MS) experiments and deuterium labeling. Published in 2011 by John Wiley & Sons, Ltd.
Observation of poly(ethylene glycol) clusters with the chlorine anion in the gas phase under electrospray conditions
Authors: Kosevich Marina V. , Zobnina Valentina G. , Chagovets Vitaliy V. , Boryak Oleg A. 
Published: February 2011

AbstractIt is demonstrated herein that poly(ethylene glycol) (PEG) oligomers can form stable complexes with the chlorine anion in the gas phase as evidenced by results from electrospray ionization mass spectrometry (ESI‐MS) and molecular dynamics simulation. While the formation of crown‐ether‐like structures by acyclic polyethers in their complexes with alkali metal cations coordinated by the ether oxygen atoms has been extensively studied, the possibility of forming ‘inversed’ quasi‐cyclic structures able to bind a monoatomic anion has not been proved till now. We have observed the formation of stable gas‐phase complexes of oligomers of PEG‐400 with the Cl− anion experimentally by ESI‐MS for the first time. It is suggested that a necessary precondition for obtaining the polyether‐chlorine anion clusters is the prevention of the formation of neutral ion pairs. Molecular dynamics simulation has demonstrated the wrapping of the Cl− anion by the PEG chain, to stabilize the PEGn•Cl− clusters in the gas phase. The conformation of the polyether chain in such quasi‐cyclic or quasi‐helical complexes is ‘inversed’ compared with that in the complexes with cations: that is its hydrogen atoms are turned towards the central anion. Awareness of the possibility of the Cl− anion being trapped in quasi‐cyclic PEG structures may be of practical importance when considering the intermolecular interactions of PEGs. Copyright © 2011 John Wiley & Sons, Ltd.
A solid‐phase bioreactor with continuous sample deposition for matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Lee Jeonghoon , Soper Steven A. , Murray Kermit K. 
Published: February 2011

AbstractWe report the development of a solid‐phase proteolytic digestion and continuous deposition microfluidic chip platform for low volume fraction collection and off‐line matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectrometry. Tryptic peptides were formed in an on‐chip bioreactor and continuously deposited onto a MALDI target plate using a motor‐driven xyz stage. The bioreactor consisted of a 4 cm × 200 µm × 50 µm microfluidic channel with covalently immobilized trypsin on an array of 50 µm diameter micropost structures with a 50 µm edge‐to‐edge inter‐post spacing. A 50 µm i.d. capillary tube was directly attached to the end of the bioreactor for continuous sample deposition. The MALDI target plate was modified by spin‐coating a nitrocellulose solution containing a MALDI matrix on the surface prior to effluent deposition. Protein molecular weight standards were used for evaluating the performance of the digestion and continuous deposition system. Serpentine sample traces 200 µm wide were obtained with a 30 fmol/mm quantity deposition rate and a 3.3 nL/mm volumetric deposition rate. Copyright © 2011 John Wiley & Sons, Ltd.
High‐throughput analysis using gated multi‐inlet mass spectrometry
Authors: Moini Mehdi , Jiang Longfei , Bootwala Samir 
Published: February 2011

AbstractGated multi‐inlet mass spectrometry is introduced for high‐throughput chemical analysis. In this design, multiple high‐pressure liquid chromatography (HPLC) columns or capillary electrophoresis (CE) capillaries are attached to multiple electrosprayers (one for each column or capillary) that spray toward a gated multi‐inlet time‐of‐flight mass spectrometer (TOF‐MS). Although all of the sprayers are spraying continuously, only one inlet is exposed at any given time for a specific duration set by the MS data system. The gated multi‐sprayer, multi‐inlet design significantly enhances the performance of the multi‐ESI, multi‐inlet TOF‐MS with minimal cost and reduces analysis time. The gated multi‐sprayer, multi‐inlet design was applied to the investigation of column‐to‐column reproducibility of multiple HPLCs using a peptide mixture and to the simultaneous analysis of four protein digests. In addition, it was applied to the analysis of peptide mixtures using eight CE capillaries. The gated multi‐inlet MS has several advantages compared to our previous non‐gated multi‐inlet MS. For example, because only one inlet is open at one time, the original manufacturer's inlet inner diameter and pumping system can be used, which enhances the sensitivity of detection for each inlet and minimizes the manufacturing cost. In addition, the number of inlets can be increased as desired. The maximum number of liquid streams that can be concurrently analyzed is limited by: (1) the number of inlets, (2) the chromatographic (electrophoretic) peak width, and (3) how fast the gate can move from one position to the next. Copyright © 2011 John Wiley & Sons, Ltd.
Sodium hydroxide permethylation of heparin disaccharides
Authors: Heiss Christian , Wang Zhirui , Azadi Parastoo 
Published: February 2011

AbstractPermethylation is a valuable and widely used tool for the mass spectrometry of carbohydrates, improving sensitivity and fragmentation and increasing the amount of information that can be obtained from tandem mass spectrometric experiments. Permethylation of most glycans is easily performed with sodium hydroxide and iodomethane in dimethyl sulfoxide (DMSO). However, permethylation has not been widely used in the mass spectrometry of glycosaminoglycan (GAG) oligosaccharides, partly because it has required the use of the difficult Hakomori method employing the methylsulfinylmethanide (‘dimsyl’) base, which has to be made in a tedious process. Additionally, the Hakomori method is not as effective as the sodium hydroxide method in making fully methylated derivatives. A further problem in the permethylation of highly sulfated oligosaccharides is their limited solubility in DMSO. This paper describes the use of the triethylammonium counterion to overcome this problem, as well as the application of the sodium hydroxide method to make permethylated heparin disaccharides and their workup to yield fully methylated disaccharides for electrospray ionization mass spectrometry. The ease, speed, and effectiveness of the described methodology should open up permethylation of GAG oligosaccharides to a wider circle of mass spectrometrists and enable them to develop further derivatization schemes in the effort to rapidly elucidate the structure of these important molecules. Permethylation may also provide new ways of separating GAG oligosaccharides in LC/MS, their increased hydrophobicity making them amenable for reversed‐phase chromatography without the need for ion pairing reagents. Copyright © 2011 John Wiley & Sons, Ltd.
Design evaluation and optimization for models of hepatitis C viral dynamics
Authors: Guedj Jeremie , Bazzoli Caroline , Neumann Avidan U. , Mentré France 
Published: February 2011

AbstractMathematical modeling of hepatitis C viral (HCV) kinetics is widely used for understanding viral pathogenesis and predicting treatment outcome. The standard model is based on a system of five non‐linear ordinary differential equations (ODE) that describe both viral kinetics and changes in drug concentration after treatment initiation. In such complex models parameter estimation is challenging and requires frequent sampling measurements on each individual. By borrowing information between study subjects, non‐linear mixed effect models can deal with sparser sampling from each individual. However, the search for optimal designs in this context has been limited by the numerical difficulty of evaluating the Fisher information matrix (FIM). Using the software PFIM, we show that a linearization of the statistical model avoids most of the computational burden, while providing a good approximation to the FIM. We then compare the precision of the parameters that can be expected using five study designs from the literature. We illustrate the usefulness of rationalizing data sampling by showing that, for a given level of precision, optimal design could reduce the total number of measurements by up 50 per cent. Our approach can be used by a statistician or a clinician aiming at designing an HCV viral kinetics study. Copyright © 2011 John Wiley & Sons, Ltd.
Lebenszyklusbetrachtungen als Grundlage für die Nachhaltigkeitsbewertung von Straßenbrücken
Authors: Graubner Carl‐Alexander , Knauff Achim , Pelke Eberhard 
Published: February 2011

AbstractLebenszyklusbetrachtungen spielen bei der Bewertung der Nachhaltigkeit von Bauwerken eine besondere Rolle. Sie fokussieren nicht nur auf die einmaligen Umweltwirkungen und die Investitionskosten bei der Herstellung von Bauwerken, sondern ermöglichen die ganzheitliche Beurteilung der fortlaufend anfallenden ökologischen und ökonomischen Wirkungen. Mit der Untersuchung von zwei Autobahnbrücken und zwei Überführungsbauwerken wird das Ziel verfolgt, einen einheitlichen Durchschnittswert für die ökologischen und die ökonomischen Wirkungen von Brückenbauwerken zu definieren. Der Beitrag befasst sich mit der Festlegung derartiger Referenzwerte und stellt erste Lösungsansätze zur Berücksichtigung des Recyclingpotentials von Materialien vor.Life cycle considerations as a base for assessment of the sustainability of road bridges. Life cycle considerations are important for the assessment of the sustainability of constructions. Taking the life cycle into account it is not only possible to determine single environmental impacts and investment costs arising during the construction of buildings, but also to assess the consecutive ecological and economical impacts. The aim of this study was to define a consistent average value for ecological as well as economical impacts of road bridges by evaluating two viaducts and two overcrossings. This article deals with the determination of those reference values and presents an approach how to deal with the recycling potential of materials within the life cycle assessment.
Time-dependent ventilation flows driven by opposing wind and buoyancy
Authors: COOMARASWAMY I. A. , CAULFIELD C. P. 
Published: February 2011

We consider transient flow in a box containing an isolated buoyancy source, ventilated by a windward high-level opening and a leeward low-level opening, so that prevailing wind acts to oppose buoyancy-driven flow. Hunt & Linden (J. Fluid Mech., vol. 527, 2005, p. 27) demonstrated that two stable steady states can exist above a critical wind strength: buoyancy-driven displacement ventilation with a two-layer stratification and wind-driven mixing ventilation with the whole interior contaminated by buoyant fluid. We present two time-dependent models for this system: a nonlinear ordinary differential equation (ODE) model following Kaye & Hunt (J. Fluid Mech., vol. 520, 2004, p. 135), assuming ‘perfect’ vertical mixing of fluid within each layer, and a partial differential equation model assuming zero vertical mixing, following Germeles (J. Fluid Mech., vol. 71, 1975, p. 601).We apply these models to an initial-value problem – the filling box with constant opposing wind. The interface between the upper hot plume fluid and the lower cool ambient air can dramatically overshoot its final level before relaxing to equilibrium; in some cases, a fully contaminated transient can occur before the buoyancy-driven two-layer steady state is reached. However, we find that for an initially completely uncontaminated box, the system converges to a stable wind-driven steady state whenever it exists. By analysing phase diagrams of the ODE model for the flow, we establish a general method of determining which final state is attained and also explain the hysteresis observed by Hunt & Linden (2005). We confirm these transient behaviours by conducting salt bath experiments in a recirculating flume tank and establish quantitative agreement between theory and experiment. Our ‘zero mixing’ model is more accurate than our ‘perfect mixing’ model for our experiments, as the upper layer remains stratified for a substantial time.
What Does Blood Membership Mean in Political Terms?: The Political Incorporation of Latin American Nikkeijin (Japanese Descendants) (LAN) in Japan 1990–2004
Authors: SHARPE MICHAEL ORLANDO 
Published: February 2011

AbstractThis attempts to explain the limited political incorporation of Latin American Nikkeijin (Japanese descendants) (LAN) in Japan 1990–2004. A 1990 reform provides Nikkeijin a renewable visa that has enabled some 300,000 LAN to emigrate to Japan on the basis of Japanese blood descent or ethnicity.1Long-term marginalized minority groups, such as Zainichi Koreans and Chinese,2are comparatively better incorporated in Japan's political system and their demands increasingly recognized as more legitimate. I argue Japan's changing ethnic citizenship regime, political opportunity structure, and structure of civil society combined with LAN language difficulties, newness of residence, small size, low minority status, and powerful myth of return limits their immigrant political incorporation in Japan.
Confucianism and Democracy: A Review of the Opposing Conceptualizations
Authors: SPINA NICHOLAS , SHIN DOH C. , CHA DANA 
Published: February 2011

AbstractThe debate over the future of East Asian democracy centers largely on the fit between democratic values and the Confucian way of life. Some interpret Confucianism's hierarchical, communitarian, and anti-pluralistic values as a roadblock to democratic consolidation. Others interpret the Confucian traditions of dissent and accountability as comparable to liberal institutions. This article surveys this scholarly debate by dividing the literature into three theoretical camps: compatibility, incompatibility, and convergence. Additionally, the few available empirical works on the Confucian-democratic dynamic are discussed and the findings are applied to the three categorizations. This review article maintains that a consensus on the relationship between Confucianism and democracy remains elusive due to the divergent conceptualizations and operationalizations of the two doctrines.
A wideband CMOS distributed amplifier with slow-wave shielded transmission lines
Authors: Lahiji Rosa R. , Katehi Linda P.B. , Mohammadi Saeed 
Published: February 2011

A four-stage distributed amplifier utilizing low-loss slow-wave shielded (SWS) transmission lines is implemented in a standard 0.13 μm Complementary Metal-Oxide-Semiconductor (CMOS) technology. The amplifier when biased in its high current operating mode of IDtotal = 46 mA (at Vdd = 2.2 V, Pdiss = 101 mW) provides a forward transmission gain of 11.3 ± 1.5 dB with a 3-dB bandwidth of 17 GHz and a gain-bandwidth product of 74 GHz. The noise figure (NF) under the same bias condition is better than 8.5 dB up to 10 GHz. The measured output-referred 1-dB compression point is higher than +2 dBm. The amplifier is also measured under low-bias condition of IDtotal = 18 mA (at Vdd = 1.15 V, Pdiss = 20.7 mW). It provides a transmission gain of 6.6 ± 1 dB, a 3-dB bandwidth of 14.8 GHz, a gain-bandwidth product of 35.5 GHz, and a NF of better than 8.6 dB up to 10 GHz. Despite using a simple four-stage cascode design, this distributed amplifier achieves very high-gain-bandwidth product at a relatively low DC power compared to the state of the art CMOS distributed amplifiers reported in the literature. This is due to the incorporation of low-loss SWS coplanar waveguide (CPW) transmission lines with a loss factor of nearly 50% of that of standard transmission lines on CMOS-grade Si substrate.
A dual wideband Sierpinski carpet fractal-shaped planar monopole antenna with CPW feed
Authors: Ghatak Rowdra , Ghoshal Swapan K. , Mondal Durbadal , Bhattacharjee Anup K. 
Published: February 2011

A dual wideband design of Sierpinski carpet fractal-shaped planar monopole antenna with a coplanar waveguide (CPW) feed is proposed in this letter. Wide impedance bandwidth of 22% at lower resonance from 4.88 to 6.08 GHz and 41.7% at higher one, which ranges from 9.5 to 14.5 GHz, is obtained. Measured realized antenna gain is around 5 dBi at the lower band centered around 5.5 GHz and are around 4.5 dBi at the higher band. A fabricated prototype is developed with good agreement between simulation and measurement.
Extracellular Ca2+ modulates ADP‐evoked aggregation through altered agonist degradation: implications for conditions used to study P2Y receptor activation
Authors: Jones Sarah , Evans Richard J. , Mahaut‐Smith Martyn P. 
Published: February 2011

SummaryADP is considered a weak platelet agonist due to the limited aggregation responses it induces in vitro at physiological concentrations of extracellular Ca2+ [(Ca2+)o]. Lowering [Ca2+]o paradoxically enhances ADP‐evoked aggregation, an effect that has been attributed to enhanced thromboxane A2 production. This study examined the role of ectonucleotidases in the [Ca2+]o‐dependence of platelet activation. Reducing [Ca2+]o from millimolar to micromolar levels converted ADP (10 μmol/l)‐evoked platelet aggregation from a transient to a sustained response in both platelet‐rich plasma and washed suspensions. Blocking thromboxane A2 production with aspirin had no effect on this [Ca2+]o‐dependence. Prevention of ADP degradation abolished the differences between low and physiological [Ca2+]o resulting in a robust and sustained aggregation in both conditions. Measurements of extracellular ADP revealed reduced degradation in both plasma and apyrase‐containing saline at micromolar compared to millimolar [Ca2+]o. As reported previously, thromboxane A2 generation was enhanced at low [Ca2+]o, however this was independent of ectonucleotidase activity. P2Y receptor antagonists cangrelor and MRS2179 demonstrated the necessity of P2Y12 receptors for sustained ADP‐evoked aggregation, with a minor role for P2Y1. In conclusion, Ca2+‐dependent ectonucleotidase activity is a major factor determining the extent of platelet aggregation to ADP and must be controlled for in studies of P2Y receptor activation.
Identification of a risk dependent microRNA expression signature in myelodysplastic syndromes
Authors: Sokol Lubomir , Caceres Gisela , Volinia Stefano , Alder Hans , Nuovo Gerard J. , Liu Chang‐Gong , McGraw Kathy , Clark Justine A. , Sigua Celia A. , Chen Dung‐Tsa , Moscinski Lynn , Croce Carlo M. , List Alan F. 
Published: February 2011

SummaryThe myelodysplastic syndromes (MDS) display both haematological and biological heterogeneity with variable leukaemia potential. MicroRNAs play an important role in tumour suppression and the regulation of self‐renewal and differentiation of haematopoietic progenitors. Using a microarray platform, we evaluated microRNA expression from 44 patients with MDS and 17 normal controls. We identified a thirteen microRNA signature with statistically significant differential expression between normal and MDS specimens (P < 0·01), including down‐regulation of members of the leukaemia‐associated MIRLET7 family. A unique signature consisting of 10 microRNAs was closely associated with International Prognostic Scoring System (IPSS) risk category permitting discrimination between lower (Low/Intermediate‐1) and higher risk (Intermediate‐2/High) disease (P < 0·01). Selective overexpression of MIR181 family members was detected in higher risk MDS, indicating pathogenetic overlap with acute myeloid leukaemia. Survival analysis of an independent cohort of 22 IPSS lower risk MDS patients revealed a median survival of 3·5 years in patients with high expression of MIR181 family compared to 9·3 years in patients with low MIR181 expression (P = 0·002). Our pilot study suggested that analysis of microRNA expression profile offers diagnostic utility, and provide pathogenetic and prognostic discrimination in MDS.
l‐asparaginase loaded red blood cells in refractory or relapsing acute lymphoblastic leukaemia in children and adults: results of the GRASPALL 2005‐01 randomized trial
Authors: Domenech Carine , Thomas Xavier , Chabaud Sylvie , Baruchel Andre , Gueyffier François , Mazingue Françoise , Auvrignon Anne , Corm Selim , Dombret Herve , Chevallier Patrice , Galambrun Claire , Huguet Françoise , Legrand Faezeh , Mechinaud Françoise , Vey Norbert , Philip Irène , Liens David , Godfrin Yann , Rigal Dominique , Bertrand Yves 
Published: February 2011

Summary l‐asparaginase encapsulated within erythrocytes (GRASPA®) should allow serum asparagine depletion over a longer period than the native form of the enzyme, using lower doses and allowing better tolerance. The GRASPALL 2005‐01 study, a multicentre randomized controlled trial, investigated three doses of GRASPA® for the duration of asparagine depletion in a phase I/II study in adults and children with acute lymphoblastic leukaemia (ALL) in first relapse. Between February 2006 and April 2008, 18 patients received GRASPA® (50 iu/kg: n = 6, 100 iu/kg: n = 6, 150 iu/kg: n = 6) after randomization, and six patients were assigned to the Escherichia coli native l‐asparaginase (E. colil‐ASNase) control group. GRASPA® was effective at depleting l‐asparagine. One single injection of 150 iu/kg of GRASPA® provided similar results to 8 × 10 000 iu/m2 intravenous injections of E. colil‐ASNase. The safety profile of GRASPA® showed a reduction in the number and severity of allergic reactions and a trend towards less coagulation disorders. Other expected adverse events were comparable to those observed with E. colil‐ASNase and there was also no difference between the three doses of GRASPA®.