bluuebunny/crossref_metadata_2025_split huggingface dataset:
MBE growth of InAsN on (100) InAs substrates
Authors: Sallet V. , Largeau L. , Mauguin O. , Travers L. , Harmand J. C. 
Published: March 2005

AbstractThe growth of InAsN on (100) InAs substrates by molecular beam epitaxy is investigated. The incorporation of nitrogen in the alloy is compared with the case of GaAsN grown on GaAs. Under the same conditions, lower nitrogen contents are systematically measured in InAsN. In both cases, nitrogen incorporation was found to be enhanced with the decrease of the arsenic flux supplied to the surface, whereas the nitrogen concentrations measured in InAsN and GaAsN as a function of the growth temperature follow opposite tendencies. For GaAsN, the N content slightly increases as the growth temperature raises from 360 °C to 460 °C. On the contrary, for InAsN alloys, no significant amount of N is observed over the range 420–460 °C and a decrease of the growth temperature down to 370 °C is required to incorporate 1% of nitrogen in InAsN. The comparison of formation enthalpies of binary constituents enables to understand these behaviours. A following discussion addresses the local environment of N atoms in GaInAsN materials. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hepatitis C virus and the immune system: a concise review
Authors: Gremion Christel , Cerny Andreas 
Published: March 2005

AbstractHepatitis C Virus (HCV) induces a chronic infection in 50%–80% of infected individuals, which can lead to cirrhosis and hepatocellular carcinoma. The inefficiency of the immune system in eliminating the virus is not well understood as humoral and cellular immune responses are induced. While a persistent infection is generally associated with a weak CD4+ and CD8+ T cell response during the acute phase, there is no good explanation as to why this response is strong enough in 20% of acutely infected people such that they spontaneously resolve the infection. However, the immune system partially controls the viral infection but due to a long‐lasting inflammatory milieu, hepatic damage occurs. During the chronic phase of the infection, HCV does not seem to be cytopathic. This aspect is still controversial as the virus was linked to the development of cholestatic syndrome or acute lobular hepatitis after liver transplant in HCV infected patients.The development of new experimental systems such as HCV pseudoparticles, genomic replicon and transfected cell lines have improved our vision of the virus cycle as well as the understanding of the mechanism of persistence. However, a convincing explanation for the chronicity of the infection in the presence of a functional immune response is still missing and is an important area of research to understand HCV immune pathogenesis.Future research should dissect mechanisms that lead to quantitatively or qualitatively inadequate immune responses, the role of the high variability of the virus, the relevance of host's genetic factors and mechanisms of immunosuppression induced by the virus. Copyright © 2005 John Wiley & Sons, Ltd.
Surface analysis of pulsed laser‐deposited V2O5 thin films and their lithium intercalated products studied by Raman spectroscopy
Authors: Ramana C. V. , Smith R. J. , Hussain O. M. , Massot M. , Julien C. M. 
Published: March 2005

AbstractVanadium pentoxide films were prepared by pulsed laser deposition (PLD) and their surface structure evolution in relation to the growth temperature and as a function of lithium intercalation was studied. The deposition was made onto various substrate materials over a wide substrate temperature range of 30–500 °C, keeping the oxygen partial pressure at 100 mTorr. The surface properties of V2O5 films were studied by Raman scattering spectroscopy in order to understand the effect of substrate temperature on the structure and growth behavior. The results indicated that the structure of PLD V2O5 films is highly dependent on the growth temperature. The Raman spectra provide additional insight into the nature of the structural changes of lithiated films, showing the appearance of the δ‐ and γ‐phases of LixV2O5. Copyright © 2005 John Wiley & Sons, Ltd.
Discovering applications of higher order functions through proof planning
Authors: Cook A. , Ireland A. , Michaelson G. , Scaife N. 
Published: March 2005

Abstract.

The close association between higher order functions (HOFs) and algorithmic skeletons is a promising source of automatic parallelisation of programs. A theorem proving approach to discovering HOFs in functional programs is presented. Our starting point is proof planning, an automated theorem proving technique in which high-level proof plans are used to guide proof search. We use proof planning to identify provably correct transformation rules that introduce HOFs. The approach has been implemented in the
λ Clam
proof planner and tested on a range of examples. The work was conducted within the context of a parallelising compiler for Standard ML.
Security analysis of efficient (Un-) fair non-repudiation protocols
Authors: Gürgens S. , Rudolph C. 
Published: March 2005

Abstract
An approach to protocol analysis using asynchronous product automata (APA) and the simple homomorphism verification tool (SHVT) is demonstrated on several variants of the well known Zhou–Gollmann fair non-repudiation protocol and on two more recent optimistic fair non-repudiation protocols. Attacks on all these protocols are presented and an improved version of the Zhou–Gollmann protocol is proposed.
Right ventricular dysfunction in chronic heart failure patients
Authors: Špinarová Lenka , Meluzín Jaroslav , Toman Jiří , Hude Petr , Krejčí Jan , Vítovec Jiří 
Published: March 2005

AimTo evaluate any differences in haemodynamic and echocardiographic parameters in patients with both left (LV) and right ventricular (RV) systolic dysfunction and in patients with isolated LV systolic dysfunction.Study groupOne hundred patients with RV systolic dysfunction defined as peak velocity of tricuspid annular motion in systole (Sa)<11.5 cm/s, and 55 patients without RV systolic dysfunction Sa>11.5 cm/s. All patients had LV systolic dysfunction, LV ejection fraction (EF) below 40%, NYHA II–IV.MethodsLV diameters, volumes and EF were measured by echocardiography. Patients underwent tissue Doppler imaging (TDI) of tricuspid annular motion with measurement of peak systolic velocity (Sa), peak early (Ea) and peak late (Aa) diastolic velocities. Right heart catheterization was also performed.ResultsPatients with RV systolic dysfunction did not differ from those without RV systolic dysfunction in terms of LV function. Patients with RV systolic dysfunction had larger RV dimension 30.6±5.8 vs. 33.9±6.7 mm, p<0.002. The patients with RV systolic dysfunction had higher values on right heart catheterization: MPAP 29.6±12.1 vs. 24.9±11.4 mm Hg, p<0.02, PCWP 20.8±10.0 vs. 17.3±9.3 mm Hg, p<0.03, PVR 189.9±123.3 vs. 137.7±94.9 dyn s cm<5, p<0.008, CVP 7.7±5.6 vs. 5.1±3.9 mm Hg, p<0.002. The patients with RV systolic dysfunction had more pronounced diastolic dysfunction measured by TDI: Ea 9.9±2.3 vs. 11.4±2.5 cm/s, p<0.0001 and Aa 13.1±4.0 vs. 16.5±4.7 cm/s, p<0.000007.ConclusionPatients with heart failure and both left and right ventricular systolic dysfunction showed more serious findings on central haemodynamics as well as more pronounced right ventricular diastolic dysfunction than those with isolated left ventricular systolic dysfunction.
Transcardiac gradients of N‐terminal B‐type natriuretic peptide in aortic valve stenosis
Authors: Kupari Markku , Turto Heikki , Lommi Jyri , Mäkijärvi Markku , Parikka Hannu 
Published: March 2005

AbstractBackgroundPlasma B‐type natriuretic peptide (BNP), as well as the N‐terminal part of the prohormone (Nt‐BNP), are frequently elevated in aortic valve stenosis (AS). Yet, their release from the heart into the circulation has never been directly studied in AS.AimTo assess the release of Nt‐BNP in AS with focus on the identification of its main determinants.MethodsWe studied 49 adult patients undergoing preoperative cardiac catheterization for isolated AS. Blood was sampled from the aortic root and the coronary sinus for Nt‐BNP determination by immunoassay.ResultsThe mean (±S.E.) transcardiac Nt‐BNP step‐up averaged 79±53 pmol/l in 11 control patients free of structural heart disease, 75±32 pmol/l in 31 AS patients free of heart failure (HF), 236±62 pmol/l in 8 AS patients with diastolic HF (ejection fraction ≥50%, pulmonary wedge pressure >14 mm Hg) and 469±66 pmol/l in 7 AS patients with systolic HF (ejection fraction <50%, wedge pressure >14 mm Hg) (p<0.001). The transcardiac Nt‐BNP gradient was independently associated with left ventricular (LV) end‐diastolic pressure (β=0.47, p<0.001) and ejection fraction (β=−0.29, p<0.019) and with co‐existent coronary artery disease (β=0.23, p=0.050).ConclusionLV diastolic and systolic dysfunction along with coronary artery disease are likely to be the key determinants of cardiac Nt‐BNP release in AS. The transcardiac Nt‐BNP gradient increases on average three‐fold with the development of diastolic HF and six‐fold in systolic HF.
CB1 cannabinoid receptor‐mediated modulation of food intake in mice
Authors: Wiley Jenny L , Burston James J , Leggett Darnica C , Alekseeva Olga O , Razdan Raj K , Mahadevan Anu , Martin Billy R 
Published: March 2005

Marijuana's appetite‐increasing effects have long been known. Recent research suggests that the CB1 cannabinoid receptor antagonist SR141716A may suppress appetite. This study represents a further, systematic investigation of the role of CB1 cannabinoid receptors in the pharmacological effects of cannabinoids on food intake.
Mice were food‐restricted for 24 h and then allowed access to their regular rodent chow for 1 h. Whereas the CB1 antagonist SR141716A dose‐dependently decreased food consumption at doses that did not affect motor activity, Δ9‐tetrahydrocannabinol (Δ9‐THC) increased food consumption at doses that had no effect on motor activity. O‐3259 and O‐3257, structural analogs of SR141716A, produced effects similar to those of the parent compound.
Amphetamine (a known anorectic) and diazepam (a benzodiazepine and CNS depressant) decreased food consumption, but only at doses that also increased or decreased motor activity, respectively. The CB2 cannabinoid receptor antagonist SR144528 and the nonpsychoactive cannabinoid cannabidiol did not affect food intake nor activity.
SR141716A decreased feeding in wild‐type mice, but lacked pharmacological activity in CB1 knockout mice; however, basal food intake was lower in CB1 knockout mice. Amphetamine decreased feeding in both mouse genotypes.
These results suggest that SR141716A may affect the actions of endogenous cannabinoids in regulating appetite or that it may have effects of its own aside from antagonism of cannabinoid effects (e.g., decreased feeding behavior and locomotor stimulation). In either case, these results strongly suggest that CB1 receptors may play a role in regulation of feeding behavior.

British Journal of Pharmacology (2005) 145, 293–300. doi:10.1038/sj.bjp.0706157
Emerging roles for cyclooxygenase‐2 in gastrointestinal mucosal defense
Authors: Wallace John L , Devchand Pallavi R 
Published: March 2005

The development of selective inhibitors of cyclooxygenase‐2 (COX‐2) was based on the concept that this enzyme played little, if any, role in modulating the ability of the gastrointestinal (GI) tract to resist and respond to injury. There is now overwhelming evidence that this is far from true. Indeed, COX‐2 mediates several of the most important components of ‘mucosal defense’, contributes significantly to the resolution of GI inflammation and plays a crucial role in regulating ulcer healing. COX‐2 also contributes to long‐term changes in GI function after bouts of inflammation.British Journal of Pharmacology (2005) 145, 275–282. doi:10.1038/sj.bjp.0706201
Distinct signalling particles containing ERK/MEK and B-Raf in PC12 cells
Authors: MacCORMICK Matt , MODERSCHEIM Tanja , van der SALM Louise W. M. , MOORE Anna , PRYOR Shona Clements , McCAFFREY Gretchen , GRIMES Mark L. 
Published: March 2005

Although several multiprotein complexes containing MAPKs (mitogen-activated protein kinases) have been identified using overexpression of kinases and scaffold proteins, the components of the complexes and their physical properties at endogenous expression levels have not been defined. We characterized a large protein complex containing a nerve-growth-factor-activated ERK (extracellular-signal-regulated kinase) and MEK (MAPK/ERK kinase) in rat pheochromocytoma (PC12) cells. This protein complex fractionated into a high-speed pellet and was resistant to non-ionic detergent treatments that solubilized membranes. Disruption of protein–protein interactions by treatment with high salt was required to facilitate immunoprecipitation of active ERK1 and co-precipitation of MEK1. Microtubule fragments were also present in the detergent-resistant high-speed pellet, and some kinases were bound to them, especially ERK1b (an alternatively spliced isoform of ERK1), which showed a strong preference for binding microtubules. The large protein complex containing ERK1 and MEK1 was resolved by velocity sedimentation from fragments of microtubules; however, it did not contain other scaffolding components known to bind ERK and MEK. B-Raf was also present in a distinct detergent-resistant, microtubule-independent protein complex slightly larger than that containing ERK and MEK. We conclude that there are two independent nerve growth factor-regulated ‘signalling particles’ with an estimated size of 60–75 S, one containing ERK1 and MEK1 and the other containing B-Raf. These signalling particles may have a role in the temporal and spatial regulation of kinase activity inside cells.
Identification and characterization of Sulfolobus solfataricus
D-gluconate dehydratase: a key enzyme in the non-phosphorylated Entner–Doudoroff pathway
Authors: KIM Seonghun , LEE Sun Bok 
Published: March 2005

The extremely thermoacidophilic archaeon Sulfolobus solfataricus utilizes D-glucose as a sole carbon and energy source through the non-phosphorylated Entner–Doudoroff pathway. It has been suggested that this micro-organism metabolizes D-gluconate, the oxidized form of D-glucose, to pyruvate and D-glyceraldehyde by using two unique enzymes, D-gluconate dehydratase and 2-keto-3-deoxy-D-gluconate aldolase. In the present study, we report the purification and characterization of D-gluconate dehydratase from S. solfataricus, which catalyses the conversion of D-gluconate into 2-keto-3-deoxy-D-gluconate. D-Gluconate dehydratase was purified 400-fold from extracts of S. solfataricus by ammonium sulphate fractionation and chromatography on DEAE-Sepharose, Q-Sepharose, phenyl-Sepharose and Mono Q. The native protein showed a molecular mass of 350 kDa by gel filtration, whereas SDS/PAGE analysis provided a molecular mass of 44 kDa, indicating that D-gluconate dehydratase is an octameric protein. The enzyme showed maximal activity at temperatures between 80 and 90 °C and pH values between 6.5 and 7.5, and a half-life of 40 min at 100 °C. Bivalent metal ions such as Co2+, Mg2+, Mn2+ and Ni2+ activated, whereas EDTA inhibited the enzyme. A metal analysis of the purified protein revealed the presence of one Co2+ ion per enzyme monomer. Of the 22 aldonic acids tested, only D-gluconate served as a substrate, with Km=0.45 mM and Vmax=0.15 unit/mg of enzyme. From N-terminal sequences of the purified enzyme, it was found that the gene product of SSO3198 in the S. solfataricus genome database corresponded to D-gluconate dehydratase (gnaD). We also found that the D-gluconate dehydratase of S. solfataricus is a phosphoprotein and that its catalytic activity is regulated by a phosphorylation–dephosphorylation mechanism. This is the first report on biochemical and genetic characterization of D-gluconate dehydratase involved in the non-phosphorylated Entner–Doudoroff pathway.
Asthmatic bronchial epithelial cells have a deficient innate immune response to infection with rhinovirus
Authors: Wark Peter A.B. , Johnston Sebastian L. , Bucchieri Fabio , Powell Robert , Puddicombe Sarah , Laza-Stanca Vasile , Holgate Stephen T. , Davies Donna E. 
Published: March 2005

Rhinoviruses are the major trigger of acute asthma exacerbations and asthmatic subjects are more susceptible to these infections. To investigate the underlying mechanisms of this increased susceptibility, we examined virus replication and innate responses to rhinovirus (RV)-16 infection of primary bronchial epithelial cells from asthmatic and healthy control subjects.
Viral RNA expression and late virus release into supernatant was increased 50- and 7-fold, respectively in asthmatic cells compared with healthy controls. Virus infection induced late cell lysis in asthmatic cells but not in normal cells. Examination of the early cellular response to infection revealed impairment of virus induced caspase 3/7 activity and of apoptotic responses in the asthmatic cultures. Inhibition of apoptosis in normal cultures resulted in enhanced viral yield, comparable to that seen in infected asthmatic cultures. Examination of early innate immune responses revealed profound impairment of virus-induced interferon-β mRNA expression in asthmatic cultures and they produced &gt;2.5 times less interferon-β protein. In infected asthmatic cells, exogenous interferon-β induced apoptosis and reduced virus replication, demonstrating a causal link between deficient interferon-β, impaired apoptosis and increased virus replication. These data suggest a novel use for type I interferons in the treatment or prevention of virus-induced asthma exacerbations.
Corrosion behaviour of carbon steel in polyvinyl alcohol
Authors: Rajendran S. , Sridevi S.P. , Anthony N. , Amalraj A. John , Sundaravadivelu M. 
Published: March 2005

PurposeTo evaluate the inhibition efficiency (IE) of polyvinyl alcohol (PVA) in controlling the corrosion of carbon steel immersed in neutral aqueous solutions containing 60 ppm of Cl−, in the absence and presence of Zn2+. To investigate the influence of sodium sulphite (Na2SO3), sodium dodecyl sulphate (SDS), pH and duration of immersion on the IE of PVA‐Zn2+ system. To analyse the protective film formed on the metal surface.Design/methodology/approachThe IE has been evaluated by weight loss method. The protective film was analysed by FTIR and fluorescence spectra.FindingsA formulation consisting of 100 ppm of PVA and 75 ppm of Zn2+ offered 81 per cent IE to carbon steel immersed in a solution containing 60 ppm of Cl−. A synergistic effect on inhibition of a combination of PVA and Zn2+ was observed during the tests. The protective film consisted of the Fe2+‐PVA complex and Zn(OH)2. It was found to be UV‐fluorescent. When SDS was added to the PVA‐Zn2+ system, the mixture showed maximum IE at the critical micelle concentration (200 ppm) of SDS (an anionic surfactant). The oxygen‐scavenging effect of Na2SO3 increased as the concentration of Na2SO3 was increased. At lower concentrations of Na2SO3, the transport of the inhibitors played a more major role than did the removal of dissolved oxygen. As the pH value was increased, the IE of the PVA‐Zn2+ system decreased. As the duration of immersion was increased, the IE was observed to decrease.Research limitations/implicationsElectrochemical studies such as polarization and AC impedance spectra will enlighten more on the mechanistic aspects of corrosion inhibition.Practical implicationsIf this study is carried out at high temperature under simulated conditions, the findings may find applications in cooling water systems.Originality/valueThe role of transport of inhibitors towards the metal surface from the bulk of the solution, formation of micelles by surfactants, removal of dissolved oxygen by oxygen scavenger, competition between formation of insoluble iron‐inhibitor complex on metal surface and formation of soluble iron chloride in influencing the inhibitive property has been investigated. The protective film was analysed by FTIR spectra and fluorescence spectra.
Ortho‐, meta‐, and para‐aminophenol‐N‐salicylidenes as corrosion inhibitors of zinc in sulfuric acid
Authors: Talati J.D. , Desai M.N. , Shah N.K. 
Published: March 2005

PurposeThe evaluation of Schiff bases derived from o‐, m‐ and p‐aminophenols and salicylaldehyde as corrosion inhibitors of zinc in sulfuric acid and to study their action mechanism.Design/methodology/approachThe effect of various parameters on the behaviour of these inhibitors has been studied using the weight loss and polarization measurements.FindingsIn general, the ortho isomer was highly effective as a corrosion inhibitor because it formed a chelate with a six‐membered ring and moreover the ortho isomer possessed pronounced electromeric effect. These inhibitors obey the Langmuir adsorption isotherm. The almost constant performance with temperature in the case of ortho and para isomers in 0.5 M sulfuric acid suggested strong adsorption bonds. The thermodynamic parameters suggested that this strong interaction of the inhibitor molecules with the metal surface resulted in spontaneous adsorption. It may be concluded that a good inhibitor is characterised by a relatively greater decrease in free energy of adsorption, lower entropy of adsorption and higher heat of adsorption. Polarization data indicated that all these isomers were predominantly cathodic inhibitors. The conjoint effect of external cathodic current and these inhibitors was either synergistic or additive.Research limitations/implicationsEven more powerful Schiff bases need to be synthesised and evaluated as corrosion inhibitors with a number of metals and alloys in diverse media, which may be effective at low concentrations.Originality/valueVery few inhibitors exhibit such excellent inhibitive effect on zinc in aggressive corrosive media. Rarely do we find such detailed studies.
Scholarly journal usage: the results of deep log analysis
Authors: Nicholas David , Huntington Paul , Watkinson Anthony 
Published: March 2005

PurposeTo present the latest results of research conducted at University College London as part of the Virtual Scholar Research Programme, investigating the impact of the digital roll‐out of information services to academics and researchers. This is the second study to look at the information seeking behaviour of academics and researchers in regard to digital journal libraries, and concentrates on the users and usage of Blackwell Synergy.Design/methodology/approachNearly a million users making ten million item requests were investigated employing deep log methods, developed by the authors to provide robust and big picture analyses of digital information consumers and their behaviour.FindingsUsage data has been embellished with user data (for 500,000 people), so enabling comparisons to be made between the information seeking behaviour, for instance, of students and staff, academics and practitioners, scientists and social scientists. We believe this is the first time this type of analysis has been attempted with logs. Of particular note is the “repeat visitor” evaluation and the analysis of one and a quarter million search sessions which categorised sessions in terms of how “busy” they were for a whole range of user groups.Research limitations/implicationsDemonstrates a powerful and new method, deep log analysis, for mapping and evaluating information seeking behaviour.Practical implicationsImportant data for publishers to enable them to target their services more effectivelyOriginality/valueProbably the first analysis of its type, hence showing an aspect of information seeking not previously seen.