bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stability of standing waves for nonlinear defocusing fourth‐order dispersive Schrödinger equation with unbounded potentials
Authors: Chen Guanggan , Zhang Jian , Wei Yunyun 
Published: March 2008

AbstractThis paper is concerned with a nonlinear defocusing fourth‐order dispersive Schrödinger equation with unbounded potentials which models propagation in fiber arrays. We analyze the global existence of the solution and also obtain the existence of the standing waves for the system. Furthermore, we prove that the standing waves are orbitally stable. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Existence of global solutions for a three‐species predator‐prey model with cross‐diffusion
Authors: Pang P. Y. H. , Wang M. X. 
Published: March 2008

AbstractIn this short note, we study a strongly coupled system of partial differential equations which models the dynamics of a two‐predator‐one‐prey ecosystem in which the prey exercises defense switching and the predators collaboratively take advantage of the prey's strategy. We prove the existence of global strong solutions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Supersingularity from group actions
Authors: Re Riccardo 
Published: March 2008

AbstractI give a sufficient condition for the action of a group on an algebraic curve defined over in order that a good reduction of the curve to positive characteristic be a supersingular curve. I apply such criterion to abelian coverings of ℙ1 ramified over three points. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A problem of D. H. Lehmer and its mean value
Authors: Xu Zhefeng , Zhang Wenpeng 
Published: March 2008

AbstractLet p be an odd prime and let a be an integer coprime to p. Denote by N (a, p) the number of pairs of integers b, c with bc ≡ a (mod p), 1 ≤ b, c < p and with b, c having different parity. The main purpose of this paper is to deduce an asymptotic formula for (N (2sad, p) – 1/2 (p – 1)), and obtain some interesting results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identifying parameters controlling soil delayed behaviour from laboratory and in situ pressuremeter testing
Authors: Yin Zhen‐Yu , Hicher Pierre‐Yves 
Published: March 2008

AbstractThe aim of this paper is to present a methodology for identifying the soil parameters controlling the delayed behaviour from laboratory and in situ pressuremeter tests by using an elasto‐viscoplastic model (EVP‐MCC) based on Perzyna's overstress theory and on the elasto‐plastic Modified Cam Clay model. The influence of both the model parameters and the soil permeability was studied under the loading condition of pressuremeter tests by coupling the proposed model equations with Biot's consolidation theory. On the basis of the parametric study, a methodology for identifying model parameters and soil permeability by inverse analysis from three levels of constant strain rate pressuremeter tests was then proposed and applied on tests performed on natural Saint‐Herblain clay. The methodology was validated by comparing the optimized values of soil parameters and the values of the same parameters obtained from laboratory test results, and also by using the identified parameters to simulate other tests on the same samples. The analysis of the drainage condition and the strain rate effect during a pressuremeter test demonstrated the coupled influence of consolidation and viscous effects on the test results. The numerical results also showed that the inverse analysis procedure could successfully determine the parameters controlling the time‐dependent soil behaviour. Copyright © 2008 John Wiley & Sons, Ltd.
Postnatal management and outcome of prenatally diagnosed lung lesions
Authors: Laje Pablo , Liechty Kenneth W. 
Published: March 2008

AbstractAdvancements in fetal diagnostic imaging have increased prenatal diagnosis of many fetal anomalies. The purpose of this chapter is to review the etiology and natural history of prenatally diagnosed cystic lung lesions, including congenital cystic adenomatoid malformations (CCAM), pulmonary sequestrations (PSs), hybrid lesions, and bronchogenic cysts, and then discuss current concepts in the management and outcome of these lesions. Copyright © 2008 John Wiley & Sons, Ltd.
Surveillance of suspected adverse reactions to natural health products in Italy
Authors: Menniti‐Ippolito Francesca , Mazzanti Gabriela , Santuccio Carmela , Angela Moro Paola , Calapai Gioacchino , Firenzuoli Fabio , Valeri Andrea , Raschetti Roberto 
Published: March 2008

AbstractPurposeNatural health products are promoted to the public as equally or more effective and less toxic than conventional drugs. However, some ‘natural’ medicines, and in particular some herbal medicines, are known to have adverse effects. The Italian Pharmacovigilance System, in charge of the Italian Medicines Agency, collects spontaneous reports only for registered drugs. The awareness of the need of surveillance of the safety of natural health products has stimulated the implementation of a suspected adverse reaction reporting system in Italy. The system has been set up by the Italian National Institute of Health.MethodsAn ad hoc reporting form can be downloaded from different institutional web sites. Voluntary reports of suspected adverse reactions are sent to the National Institute of Health and are evaluated by a multidisciplinary group of experts.ResultsFrom April 2002 to March 2007, 233 spontaneous reports of suspected adverse reactions to natural health products were collected. A large proportion of suspected adverse reactions were serious: hospitalization was reported in 35% of forms; 6% reported life threatening clinical events and two fatal events were notified. About 50% of suspected adverse reactions were related to gastrointestinal, skin, psychiatric and nervous system disorders. Mainly herbal products (66%) were involved. Twenty‐one cases of hepatitis of various seriousness were reported. Twenty‐one reports were associated with 27 homeopathic preparations, mostly preparations containing mixtures of substances. Fourteen reports regarded suspected reactions to products containing propolis.ConclusionSafety and efficacy of ‘natural’ medicines have not been thoroughly investigated. It is important to improve communication with the public on safety issues. Encouraging spontaneous reporting can contribute to improve awareness among health personnel and patients about the benefit–harm profile of these remedies. Copyright © 2008 John Wiley & Sons, Ltd.
Replicated studies of two randomized trials of angiotensin‐ converting enzyme inhibitors: further empiric validation of the ‘prior event rate ratio’ to adjust for unmeasured confounding by indication
Authors: Tannen Richard L. , Weiner Mark G. , Xie Dawei 
Published: March 2008

AbstractPurposeUsing data from the United Kingdom General Practice Research Database (GPRD) randomized controlled trials (RCTs) were replicated to determine whether identifiable study characteristics and/or analytic methods influence the validity of observational studies.MethodsThis study reports GPRD replications of 2 RCTs that investigated whether angiotensin‐converting enzyme inhibitors (ACEIs) improve cardiovascular outcomes in patients without congestive heart failure at high risk for cardiovascular disease (heart outcomes prevention evaluation (HOPE) and EUROPA). The GPRD studies replicated to the extent feasible all aspects of these RCTs except for randomization.ResultsWith adjustment for confounders using conventional biostatistical techniques, both GPRD studies exhibited results divergent from the RCTs. Myocardial infarction, stroke, congestive heart failure, and coronary revascularization were increased in the Exposed group of both GPRD studies; whereas these outcomes either were decreased or unchanged by ACEI therapy in both RCTs. The results also were analyzed with a new method that appears to adjust for both identified and unmeasured confounders. With this methodology that employs the ratio of event rates between the Exposed and Unexposed cohorts prior to study start time to adjust the study hazard ratio (HR), the GPRD results for myocardial infarction, stroke, and coronary revascularization were largely similar to those found in the two RCTs.ConclusionsThis study provides additional empiric evidence suggesting that this new analytic methodology, ‘prior events rate ratio (PERR)’ adjustment, is a promising solution for the vexing problem of ‘unmeasured confounding’ in observational studies. Additional statistical simulations are needed to fully appreciate the applicability and limitations of this method. Copyright © 2008 John Wiley & Sons, Ltd.
Replication of the Scandinavian Simvastatin Survival Study using a primary care medical record database prompted exploration of a new method to address unmeasured confounding
Authors: Weiner Mark G. , Xie Dawei , Tannen Richard L. 
Published: March 2008

AbstractPurposeTo examine whether identifiable study characteristics and/or analytic methods used determine observational study validity, as assessed by replicating randomized controlled trials using observational data.MethodsA cohort from the United Kingdom General Practice Research Database (GPRD) was used to replicate the Scandinavian Simvastatin Survival Study RCT, which investigated statin treatment of hypercholesterolemic subjects with coronary heart disease. All aspects of the RCT except randomization were replicated to the extent possible in the GPRD study, which included 2,871 Unexposed and 1,280 statin‐treated Exposed subjects.ResultsOverall mortality [adjusted hazard ratio 0.71 (0.53–0.96)] and myocardial infarction [adjusted HR 0.79 (0.61–1.02)] decreased in the GPRD study similar to the RCT. Coronary revascularization increased two‐fold in the GPRD study, whereas it decreased significantly in the RCT [0.63 (0.54–0.74)]. This latter disparity prompted use of a new methodology to adjust for unmeasured confounding, which yielded an adjusted HR [1.0 (0.75–1.33)] more comparable to the RCT.ConclusionsThis study provides additional evidence that a replicated GPRD observational study can yield results reasonably similar to a RCT. More important, it provides preliminary evidence suggesting that a new analytic methodology may adjust for unmeasured confounding, the major limitation to research using observational data. Copyright © 2008 John Wiley & Sons, Ltd.
Comparison of tribological behaviour and biocompatibility of Ti6Al4V alloy after ion implantation or thermal oxidation
Authors: Díaz C. , Lutz J. , Mändl S. , García J. A. , Martínez R. , Rodríguez R. J. , Damborenea J. J. , Arenas M. A. , Conde A. 
Published: March 2008

AbstractThis paper describes improvements of the tribological properties and the biocompatibility of Ti6Al4V alloy implanted by oxygen plasma immersion (PIII) in comparison with other treatments like thermal oxidation, conventional beamline ion implantation (II) of nitrogen and a combination of both thermal oxidation and II of nitrogen.Ball‐on‐disc friction and wear tests were performed to investigate the modifications introduced for each treatment. Biocompatibility tests were carried out by controlling Al and V ion migration in a Hank's solution simulating the human body fluid. The reported results indicate that PIII provide a promising method to improve the characteristics of the Ti6Al4V alloy to be used in human body implants. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Efficiency of a Venetian blind filter in PBIID
Authors: Schirmer Sabine , Manova Darina , Mändl Stephan 
Published: March 2008

AbstractPlasma Based Ion Implantation and Deposition (PBIID) is a preferred method for obtaining high‐quality, defect‐free coatings with excellent adhesion properties. However, a major drawback is the generation of unwanted macroparticles with a diameter between 1 and 25 µm at the cathode of the vacuum arc used to produce the metal ions. A Venetian blind filter with louvers oriented at a defined angle towards plasma can be used to improve the quality of these thin films. Film quality effects were complex, depending on cathode material, gaas fill pressure, gas fill species and louvre angle. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Predicted depth profiles for nitrogen‐ion implantation into gallium arsenide
Authors: Risch M. , Bradley M. 
Published: March 2008

AbstractWe present a new method to predict the spatial variation of the band gap in nitrogen‐implanted gallium arsenide. Band gap engineering of a GaAsN alloy was employed to design an emission peak at 1.3 µm. Based on SRIM simulations, we propose a concentration of 6% N in GaAs at the plateau of the trapezoidal depth profile for the desired band gap. The depth profile could be manufactured by virtue of subsequent high voltage pulses. Software based on the Lieberman model was developed to predict fluences from measurements of a simple Langmuir probe and the time dependent electrode potential. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Light source inner surface changes depending on treatment
Authors: Skudra A. , Zorina N. , Gavare Z. , Berzins M. , Erts D. 
Published: March 2008

AbstractOur work is connected with the preparation of different type of electrodeless discharge lamps. In this work we investigate the influence of the SiO2 glass wall treatment procedures on the inner surface of the electrodeless lamps. Three different treatment procedures were applied: vacuum cleaning, vacuum‐thermal cleaning and training in the high frequency discharge. The surface modification has been investigated by means of atomic force microscopy. Substantial changes of the SiO2 glass surface have been observed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
PI3D processing of DLC coatings for different applications
Authors: Nikiforov S. A. , Ryoo H. J. , Oh H. S. , Rim G. H. 
Published: March 2008

AbstractDLC (a ‐C:H) and Si‐DLC coatings have been deposited on various materials (steel, aluminium, silicon, glass, polymers) using a 1‐m3 interior‐antenna ICP PI3D facility with HMDSO and toluene as precursors. For conformal treatment of 3‐D workpiececs, a low‐voltage (0.5 ‐ 1) kV, high repetition rate (up to 70 kHz) pulsing was applied. However, DLC formation on dielectric substrates was performed at higher (2 ‐ 10) kV voltage using short (1 ‐ 1.5) μs pulses to minimize surface charging. Coating adhesion was achieved by formation of multi layer structure comprising Si‐containing buffer layer, transient layer, DLC layer with gradually increasing hardness, and top hard DLC. Film hardness was (5 ‐ 20) GPa, and the deposition rate (4 ‐ 0.5) μm/h. DLC surface roughness was (0.7 ‐ 60) nm and water contact angle 70° ‐ 110° depending on process parameters which implies various applications. Batch processing of sliding parts, cutting tools, glass moulds was performed. Double‐side DLC coating on polymer web eliminated its rolling up due to the coating stress. With novel ICP antenna the DLC processing is promising for large‐scale nano pattern transfer technology. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Highly localized ion focusing effects in PBIID
Authors: Haberkorn Frank , Todorova Dessislava , Manova Darina , Mändl Stephan 
Published: March 2008

AbstractPlasma Based Ion Implantation and Deposition (PBIID) is characterized by a complex interaction of a supersonic plasma flux, a plasma sheath expanding and receding on a timescale of microseconds and a substrate which can be of an arbitrary complex shape. It is shown that ions impinging on the substrate in the wake region consist of two groups with strongly differing incidence angles. At the same time, localized ion focusing is observed only for very long pulses of 50 µs and intermediate voltages of 2.5 – 3.5 kV, independent of the cathode material – Ti or Al – and the Ar background pressure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of chemical binding states between ultra shallow plasma doping (PD) and ion implantation (I/I) samples by using hard X‐ray photoelectron spectroscopy (HX‐PES)
Authors: Jin C. G. , Kobata M. , Sasaki Y. , Okashita K. , Nakamoto K. , Mizuno B. , Ikenaga E. , Kobayashi K. 
Published: March 2008

AbstractWe measured HX‐PES (Si 1s) of ultra low energy ion implantion (I/I) samples combined with Ge pre‐amorphizaiton ion implantation (Ge‐PAI) before and after spike RTA, and compared it with that of plasma doping (PD) samples. As‐doped I/I sample showed higher hole density compared to as‐doped PD sample due to lower defect induced carrier trap. Ge‐PAI+I/I sample showed strong asymmetric in lower binding energy region due to Si‐Ge bonding. After spike RTA, PD sample showed superior impurity activation than that of Ge‐PAI+I/I sample. Both Ge‐PAI+I/I and PD sample showed excellent recrystallization after spike RTA. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ion internal energy distributions validate the charge residue model for small molecule ion formation by spray methods
Authors: Touboul David , Jecklin Matthias Conradin , Zenobi Renato 
Published: March 2008

AbstractThis paper reports a detailed study of the internal energy distribution of ions formed by four electrospray ionization (ESI)‐related ionization methods, with particular emphasis on electrosonic spray ionization (ESSI). Substituted benzylpyridinium ions were used as thermometer ions to probe the internal energy distribution. The influence of different instrumental parameters was studied. Cone and skimmer voltages as well as the collision energy were found to strongly affect the ion internal energy distribution, whereas the distance between the emitter and the inlet of the mass spectrometer, the nebulizing gas pressure or the flow rate showed no influence. The internal energy distribution obtained with an ESSI source was compared with those obtained for electrospray (ESI), nanoelectrospray (nanoESI) and sonic spray ionization (SSI) on the same mass spectrometer with the same instrumental parameters. No clear differences were observed. As the charge residue model is the only ion formation mechanism possible for SSI, we conclude that benzylpyridinium ions are formed by the pathway suggested by this model. Copyright © 2008 John Wiley & Sons, Ltd.
Differentiation between isomeric triantennary N‐linked glycans by negative ion tandem mass spectrometry and confirmation of glycans containing galactose attached to the bisecting (β1‐4‐GlcNAc) residue in N‐glycans from IgG
Authors: Harvey David J. , Crispin Max , Scanlan Chris , Singer Bernhard B. , Lucka Lothar , Chang Veronica T. , Radcliffe Catherine M. , Thobhani Smita , Yuen Chun‐Ting , Rudd Pauline M. 
Published: March 2008

AbstractNegative ion tandem mass spectrometry (MS/MS) spectra of three isomeric triantennary N‐linked glycans provided clear differentiation between the isomers and confirmed the occurrence of an isomer that was substituted with galactose on a bisecting GlcNAc (1 → 4‐substituted on the core mannose) residue recently reported by Takegawa et al. from N‐glycans released from human immunoglobulin G (IgG). We extend this analysis of human serum IgG to reveal an analogue of the fucosylated triantennary glycan reported by Takegawa et al. together with a third compound that lacked both the sialic acid and the fucose residues. In addition, we demonstrate the biosynthesis of bisected hybrid‐type glycans with the galactose modification, with and without core fucose, on the stem cell marker glycoprotein, 19A, expressed in a partially ricin‐resistant human embryonic kidney cell line. It would appear, therefore, that this modification of N‐linked glycans containing a galactosylated bisecting GlcNAc residue may be more common than originally thought. Negative ion MS/MS analysis of glycans is likely to prove an invaluable tool in the analysis and monitoring of therapeutic glycoproteins. Copyright © 2008 John Wiley & Sons, Ltd.
A comparison of carbon and nitrogen stable isotope ratios of fish tissues following lipid extractions with non‐polar and traditional chloroform/methanol solvent systems
Authors: Logan John M. , Lutcavage Molly E. 
Published: March 2008

AbstractStable isotope ratios act as chemical tracers of animal diet, and are used to study food web dynamics. Because carbon stable isotope values are influenced by tissue lipid content, a number of extraction methods have been used to remove lipid bias, but, in some species and tissues, extractions also alter nitrogen isotope values. We have analyzed δ13C and δ15N in Atlantic bluefin tuna liver and white muscle, and whole Atlantic herring, fish tissues covering a wide range of lipid content (bulk C:N 3.1–12.5). In order to compare δ13C and δ15N values from traditional chloroform/methanol extractions with non‐polar solvent alternatives, we analyzed samples following (1) no treatment, (2) lipid removal using chloroform/methanol (2:1), and (3) Soxhlet extractions using chloroform, diethyl ether or hexane. Chloroform/methanol and chloroform extractions produced the lowest C:N values and highest δ13C values. In bluefin tuna, chloroform and hexane extractions significantly altered liver δ15N, and all methods significantly altered δ15N values in white muscle. Whole Atlantic herring δ15N was not altered by any extraction method, while the 2:1 chloroform/methanol extraction most completely removed fish tissue lipid components. Our results indicate that δ15N effects are not limited to common chloroform/methanol extractions and suggest that chloroform/methanol is the most effective extraction for δ13C correction. Given evidence for δ15N alteration among all tested methods, mathematical correction approaches should be further explored as an alternative to lipid correction. Copyright © 2008 John Wiley & Sons, Ltd.
High‐throughput, accurate mass liquid chromatography/tandem mass spectrometry on a quadrupole time‐of‐flight system as a ‘first‐line’ approach for metabolite identification studies
Authors: Tiller Philip R. , Yu Sean , Castro‐Perez Jose , Fillgrove Kerry L. , Baillie Thomas A. 
Published: March 2008

AbstractThroughput for drug metabolite identification studies has been increased significantly by the combined use of accurate mass liquid chromatography/tandem mass spectrometry (LC/MS/MS) data on a quadrupole time‐of‐flight (QTOF) system and targeted data analysis procedures. Employed in concert, these tools have led to the implementation of a semi‐automated high‐throughput metabolite identification strategy that has been incorporated successfully into lead optimization efforts in drug discovery. The availability of elemental composition data on precursor and all fragment ions in each spectrum has greatly enhanced confidence in ion structure assignments, while computer‐based algorithms for defining sites of biotransformation based upon mass shifts of diagnostic fragment ions have facilitated identification of positions of metabolic transformation in drug candidates. Adoption of this technology as the ‘first‐line’ approach for in vitro metabolite profiling has resulted in the analysis of as many as 21 new chemical entities on one day from diverse structural classes and therapeutic programs. Copyright © 2008 John Wiley & Sons, Ltd.
A density functional study of the electric and magnetic properties of a benzene–transition‐metal multiple‐decker sandwich chain
Authors: Mahmudur Rahman M. , Muhida Rifki , Kasai Hideaki 
Published: March 2008

AbstractWe investigate the stability as well as the electric and magnetic properties of a benzene–transition‐metal multiple‐decker sandwich chain [M(C6H6)]∞ (M = ScNi). By performing first‐principles calculation based on the density functional theory, we find that the system [M(C6H6)]∞ is stable. We find that for the early transition‐metal atoms (ScMn) the binding energies are larger than those of the late transition metal atoms (FeNi), which is consistent with the experimental results. In case of electric properties, our investigations show that for the case of ScV, these are metallic, while for CrNi they are semiconducting. Copyright © 2008 John Wiley & Sons, Ltd.