bluuebunny/crossref_metadata_2025 huggingface dataset:
Common RyR2 variants associate with ventricular arrhythmias and sudden cardiac death in chronic heart failure
Authors: Ran Yuqin , Chen Jingzhou , Li Ning , Zhang Weili , Feng Li , Wang Rongrong , Hui Rutai , Zhang Shu , Pu Jielin
Published: April 2010

Ca2+ cycling plays a critical role in heart failure and lethal arrhythmias. As susceptibility to sudden cardiac death is considered to be a heritable trait in general population, we have therefore investigated whether potentially functional variants of genes encoding RyR2 (ryanodine receptor 2) and the L-type Ca2+ channel are related to the risk of ventricular arrhythmias and sudden cardiac death in CHF (chronic heart failure) in a case-control study. We found that the A allele of rs3766871 in RYR2 was associated with an increased risk of ventricular arrhythmias in patients with CHF {odds ratio, 1.66 [95% CI (confidence interval), 1.21–2.26]; P=0.002}. During a median follow-up period of 32 months in 1058 (85.0%) patients, 296 (28.0%) patients died from heart failure, of whom 141 (47.6%) had sudden cardiac death. After adjustment for age, gender and suspected risk factors, patients carrying the A allele of rs3766871 had an increased risk of cardiac death {HR (hazard ratio), 1.53 [95% CI, 1.11–2.12]; P=0.010} and sudden cardiac death [HR, 1.92 (95% CI, 1.25–2.94); P=0.003]. Patients carrying the A allele of rs790896 in RYR2 had a reduced risk of sudden cardiac death [HR, 0.65 (95% CI, 0.45–0.92); P=0.015]. In conclusion, the A allele of rs3766871 in RYR2 not only associates with ventricular arrhythmias, but also serves as an independent predictor of sudden cardiac death, and the A allele of rs790896 in RYR2 is a protective factor against sudden cardiac death in patients with CHF.
High-sensitive troponin T: a novel biomarker for prognosis and disease severity in patients with pulmonary arterial hypertension
Authors: Filusch Arthur , Giannitsis Evangelos , Katus Hugo A. , Meyer Franz J.
Published: April 2010

PAH (pulmonary arterial hypertension) is the leading cause of fatal right ventricular failure. However, rarely detectable, cTnT [cardiac TnT (troponin T)] is a significant prognostic marker. Therefore the aim of the present study was to evaluate the usefulness of a novel high-sensitive cTnT (hsTnT) assay as a parameter for functional and prognostic evaluation of PAH patients. In 55 PAH patients (idiopathic, n=20; chronic thromboembolic, n=30; and interstitial lung disease, n=5) with a mean pulmonary artery pressure of 45±18 mmHg, cTnT was measured by a fourth-generation conventional assay and a novel hsTnT assay with a lower detection limit at 2 pg/ml [total imprecision <10% at the 99th percentile value (13.4 pg/ml)]. In 90.9% of patients, cTnT was detectable using the hsTnT assay and in 30.9% using the fourth-generation assay. Concentrations >99th percentile were observed in 27.3% using hsTnT compared with 10.9% using the fourth-generation assay. A total of five out of six patients with cTnT values >30 pg/ml (fourth-generation assay) or >29.5 pg/ml (hsTnT assay) died during the 12-month follow-up. There was a correlation between hsTnT and 6-min walk distance (r=−0.92, P=0.0014), right ventricular systolic strain (r=0.95, P=0.0018) and strain rate (r=0.82, P=0.0021). In AUC (area under the curve) analysis, hsTnT predicted death at least as effectively as hFABP (heart-type fatty-acid-binding protein) or NT-proBNP (N-terminal pro-brain natriuretic protein). Moreover, hsTnT predicted a WHO (World Health Organization) functional class >II better than NT-proBNP or hFABP. In conclusion, in PAH patients, the novel biomarker hsTnT is associated with death and advanced WHO functional class, and is related to systolic right ventricular dysfunction and an impaired 6-min walk distance.
Comparative effects of telmisartan, sitagliptin and metformin alone or in combination on obesity, insulin resistance, and liver and pancreas remodelling in C57BL/6 mice fed on a very high-fat diet
Authors: Souza-Mello Vanessa , Gregório Bianca M. , Cardoso-de-Lemos Fernando S. , de Carvalho Laís , Aguila Márcia B. , Mandarim-de-Lacerda Carlos A.
Published: April 2010

The aim of the present study was to evaluate the effects of monotherapies and combinations of drugs on insulin sensitivity, adipose tissue morphology, and pancreatic and hepatic remodelling in C57BL/6 mice fed on a very HF (high-fat) diet. Male C57BL/6 mice were fed on an HF (60% lipids) diet or SC (standard chow; 10% lipids) diet for 10 weeks, after which time the following drug treatments began: HF-T (HF diet treated with telmisartan; 5.2 mg·kg−1 of body weight·day−1), HF-S (HF diet treated with sitagliptin; 1.08 g·kg−1 of body weight·day−1), HF-M (HF diet treated with metformin; 310.0 mg·kg−1 of body weight·day−1), HF-TM (HF diet treated with telmisartan+metformin), HF-TS (HF diet treated with telmisartan+sitagliptin) and HF-SM (HF diet treated with sitagliptin+metformin). Treated groups also had free access to the HF diet, and treatments lasted for 6 weeks. Morphometry, stereological tools, immunostaining, ELISA, Western blot analysis and electron microscopy were used. The HF diet yielded an overweight phenotype, an increase in oral glucose intolerance, hyperinsulinaemia, hypertrophied islets and adipocytes, stage 2 steatosis (>33%), and reduced liver PPAR-α (peroxisome-proliferator-activated receptor-α) and GLUT-2 (glucose transporter-2) levels, concomitant with enhanced SREBP-1 (sterol-regulatory-element-binding protein-1) expression (P<0.0001). Conversely, all drug treatments resulted in significant weight loss, a reversal of insulin resistance, islet and adipocyte hypertrophy, and alleviated hepatic steatosis. Only the HF-T and HF-TS groups had body weights similar to the SC group at the end of the experiment, and the latter treatment reversed hepatic steatosis. Increased PPAR-α immunostaining in parallel with higher GLUT-2 and reduced SREBP-1 expression may explain the favourable hepatic outcomes. Restoration of adipocyte size was consistent with higher adiponectin levels and lower TNF-α (tumour necrosis factor-α) levels (P<0.0001) in the drug-treated groups. In conclusion, all of the drug treatments were effective in controlling the metabolic syndrome. The best results were achieved using telmisartan and sitagliptin as monotherapies or as a dual treatment, combining partial PPAR-γ agonism and PPAR-α activation in the liver with extended incretin action.
Physics of ice friction
Authors: Kietzig Anne-Marie , Hatzikiriakos Savvas G. , Englezos Peter
Published: April 2010

Although the study of friction has a long history, ice friction has only been investigated during the last century. The basic physical concepts underlying the different friction regimes, such as boundary, mixed, and hydrodynamic friction are also relevant to ice friction. However, these friction regimes must be described with respect to the thickness of the lubricating liquidlike layer on ice. In this review the state of knowledge on the physics of ice friction is discussed. Surface melting theories are introduced. These theories attempt to explain the existence and nature of the liquidlike surface layer on ice at any temperature and without any load applied. Pressure melting, as the long-time explanation for the ease of ice friction, is discussed, together with the prevailing theory of frictional heating. The various laboratory setups for ice friction measurements are presented as well as their advantages and disadvantages. The individual influence of the different parameters on the coefficient of ice friction is discussed; these include the effects of temperature, sliding velocity, normal force exerted by the sliding object, the contact area between ice and slider, relative humidity, and also properties of the slider material such as surface roughness, surface structure, wettability, and thermal conductivity. Finally, the most important ice friction models based on the frictional heating theory are briefly introduced and research directions on the subject of ice friction are discussed.
Direct observation of an anisotropic in-plane residual stress induced by B addition as an origin of high magnetic anisotropy field of Ru/FeCoB film
Authors: Hirata Ken-ichiro , Gomi Shunsuke , Mashiko Yasuhiro , Nakagawa Shigeki
Published: April 2010

Although boron-free FeCo films prepared on a Ru underlayer exhibits isotropic in-plane magnetic property, boron added FeCoB films prepared on Ru underlayer revealed large in-plane magnetic anisotropy with a high anisotropy field of 500 Oe. The effect of boron addition on the in-plane anisotropic residual stress in FeCoB film was investigated using sin2 ψ method of x-ray diffraction analysis. Large isotropic compressive stress was observed in Ru/FeCo film. In contrast, anisotropic in-plane residual stress was observed in Ru/FeCoB film. The compressive stress along the easy axis of Ru/FeCoB film is released more than that along the hard axis. Such anisotropic residual stress is regarded as an origin of the in-plane magnetic anisotropy through inverse magnetostriction effect. Owing to the configuration of the facing targets sputtering system, boron atoms are sputtered and deposited anisotropically, and so they penetrate FeCo crystals and release the compressive stress along the incidence direction.
Collinear phase matching for second harmonic generation using conoscopic interferometry
Authors: De A. , Puri A.
Published: April 2010

The problem of finding phase-matching directions in noncentrosymmetric biaxial crystals is simplified here by the use of Conoscopic interferometry. Based on vector relations for wave propagation in birefringent media and solutions to phase-matching equations, we show that phase matching directions can be located on the conoscopic interferograms and that fringe numbers for dark-isochromes can be used as a guide to find phase-matching directions for a biaxial crystal. This technique can be generalized and extended to any anisotropic crystal. We have demonstrated this method for the particular case of a biaxial KTiOPO4 crystal, where it is found to be particularly suitable for finding the optimum-phase-matching directions.
Finite element model-simulation-based characterization of a magnetostrictive gyrosensor
Authors: Marschner U. , Graham F. , Mudivarthi C. , Yoo J.-H. , Neubert H. , Flatau A. B.
Published: April 2010

This paper analyzes a prototype microgyrosensor that employs the magnetostrictive alloy Galfenol for transduction of Coriolis-induced forces into an electrical output for quantifying a given angular velocity. The magnetic induction distribution in the Galfenol sensor patch depends on its bending shape and magnetoelastic properties and is investigated using a finite element model. Fluctuations in magnetic induction caused by a sinusoidal rotation of the sensor produce an amplitude modulated voltage in a surrounding coil which is simulated and measured.
Small-amplitude positron-acoustic double layers
Authors: Tribeche Mouloud
Published: April 2010

Small-amplitude positron-acoustic double layers (PA-DLs) in a four-component plasma model consisting of two-temperature positron, isothermal electrons, and immobile ions are investigated. Due to the relative particle fractions and the temperature ratio, our plasma model can admit compressive as well as rarefactive PA-DLs. As the relative number of hot positrons increases, the negative PA-DL shrinks and, beyond a certain critical value, develops into a positive structure allowing therefore the existence of compressive PA-DLs. This critical value is lowered as the relative number of hot electrons decreases. The critical Mach Mc number, above which only rarefactive PA-DL is observed, is shifted towards higher values as the relative amount of hot positrons becomes important. A decrease of the temperature ratio σ=Te/Tph provides qualitatively the same results but with a net shift of Mc towards lower values.
Fast stochastic simulation of biochemical reaction systems by alternative formulations of the chemical Langevin equation
Authors: Mélykúti Bence , Burrage Kevin , Zygalakis Konstantinos C.
Published: April 2010

The Chemical Langevin Equation (CLE), which is a stochastic differential equation driven by a multidimensional Wiener process, acts as a bridge between the discrete stochastic simulation algorithm and the deterministic reaction rate equation when simulating (bio)chemical kinetics. The CLE model is valid in the regime where molecular populations are abundant enough to assume their concentrations change continuously, but stochastic fluctuations still play a major role. The contribution of this work is that we observe and explore that the CLE is not a single equation, but a parametric family of equations, all of which give the same finite-dimensional distribution of the variables. On the theoretical side, we prove that as many Wiener processes are sufficient to formulate the CLE as there are independent variables in the equation, which is just the rank of the stoichiometric matrix. On the practical side, we show that in the case where there are m1 pairs of reversible reactions and m2 irreversible reactions there is another, simple formulation of the CLE with only m1+m2 Wiener processes, whereas the standard approach uses 2m1+m2. We demonstrate that there are considerable computational savings when using this latter formulation. Such transformations of the CLE do not cause a loss of accuracy and are therefore distinct from model reduction techniques. We illustrate our findings by considering alternative formulations of the CLE for a human ether a-go-go related gene ion channel model and the Goldbeter–Koshland switch.
Ultrafast electron beam imaging of femtosecond laser-induced plasma dynamics
Authors: Li Junjie , Wang Xuan , Chen Zhaoyang , Clinite Richard , Mao Samuel S. , Zhu Pengfei , Sheng Zhengming , Zhang Jie , Cao Jianming
Published: April 2010

Plasma dynamics in the early stage of laser ablation of a copper target are investigated in real time by making ultrafast electron shadow images and electron deflectometry measurements. These complementary techniques provide both a global view and a local perspective of the associated transient electric field and charge expansion dynamics. The results reveal that the charge cloud above the target surface is composed predominantly of thermally ejected electrons and that it is self-expanding, with a fast front-layer speed exceeding 107 m/s. The average electric field strength of the charge cloud induced by a pump fluence of 2.2 J/cm2 is estimated to be ∼2.4×105 V/m.
Measurement of the total energy losses per electron-ion lost in various mixed gas inductively coupled plasmas
Authors: Ku Ju-Hwan , Lee Young-Kwang , Chung Chin-Wook
Published: April 2010

The total energy loss per electron-ion lost was measured at various gases and mixtures (Ar, He, N2, O2, Ar/N2, Ar/O2, He/N2, and He/O2) in the pressure range of 5–50 mTorr in an inductively coupled plasma. To measure electron temperatures and ion fluxes at a chamber wall, the floating harmonics method was used. The absorbed power was determined by measuring antenna resistances and currents. The total energy losses were obtained from the power balance equation of a global model. In the case of Ar mixture plasma with molecular gas, the total energy loss decreased with fractional Ar flow rate. He mixture plasma decreased more than the decrease in total energy loss of Ar mixture plasma. These experimental results were compared and were consistent with average collisional energy loss.
Novel properties of boron nitride nanotubes encapsulated with Fe, Co, and Ni nanoclusters
Authors: Ghosh Saurabh , Nigam Sandeep , Das G. P. , Majumdar Chiranjib
Published: April 2010

Using state of the art spin polarized density functional theory, we report the stability and structural aspects of small magnetic clusters M4 (M=Fe, Co, and Ni) inside an inert boron nitride nanotube [BNNT(10,0)]. The geometry optimization was carried out starting with various possible configurations [one-dimensional (1D) linear chain, two-dimensional (2D) planar rhombus, and three-dimensional (3D) tetrahedral], and the results reveal that the ground state geometry of M4 cluster inside the nanotube favors 3D configuration over others. Moreover, these small clusters are found to retain their magnetic nature with a small reduction in the total magnetic moment even after encapsulation. The radial confinement effect on the atomic structure of M4 clusters was investigated by optimizing the Co4 (prototype example) in BNNT(10, 0), BNNT(9, 0), and BNNT(8, 0). It is found that with the increase in radial confinement (smaller diameter), the Co4 cluster becomes more compact, which further leads to significant changes in the electronic and magnetic properties. The electronic density of states analysis of the M4 clusters inside BNNT(10,0) showed the appearance of additional electronic states in the band gap of BNNT(10, 0). In order to underscore the possibility of functionalizing these encapsulated tubes, we have performed the adsorption of oxygen molecules on it. The adsorption of oxygen in the molecular form with elongated O–O bonds further justifies its application in the oxidative catalysis.
Static polarizability surfaces of the van der Waals complex CH4–N2
Authors: Buldakov Mikhail A. , Cherepanov Victor N. , Kalugina Yulia N. , Zvereva-Loëte Natalia , Boudon Vincent
Published: April 2010

The static polarizability surfaces of the van der Waals complex CH4–N2 have been calculated for a broad range of intermolecular separations and configurations in the approximation of rigid interacting molecules. The calculations have been carried out at the CCSD(T) and MP2 levels of the theory using the aug-cc-pVTZ basis set with the BSSE correction and within the framework of the classical long-range multipolar induction and dispersion interactions. It was shown that the results of analytical polarizability calculations for the CH4–N2 complex are in a good agreement with the ab initio polarizabilities in the outer part of the van der Waals well on the complex potential surface. Ab initio calculations of the polarizability tensor invariants for the complex being in the most stable configurations were carried out. The change in the polarizability of CH4–N2 due to the deformation of the CH4 and N2 monomers at the formation of the complex was estimated. In the framework of the analytical approach the polarizability functions α¯ii(R) of the free oriented interacting molecules CH4 and N2 were calculated.
A desorption mechanism of water following vacuum-ultraviolet irradiation on amorphous solid water at 90 K
Authors: Hama Tetsuya , Yokoyama Masaaki , Yabushita Akihiro , Kawasaki Masahiro , Andersson Stefan , Western Colin M. , Ashfold Michael N. R. , Dixon Richard N. , Watanabe Naoki
Published: April 2010

Following 157 nm photoexcitation of amorphous solid water and polycrystalline water ice, photodesorbed water molecules (H2O and D2O), in the ground vibrational state, have been observed using resonance-enhanced multiphoton ionization detection methods. Time-of-flight and rotationally resolved spectra of the photodesorbed water molecules were measured, and the kinetic and internal energy distributions were obtained. The measured energy distributions are in good accord with those predicted by classical molecular dynamics calculations for the kick-out mechanism of a water molecule from the ice surface by a hot hydrogen (deuterium) atom formed by photodissociation of a neighboring water molecule. Desorption of D2O following 193 nm photoirradiation of a D2O/H2S mixed ice was also investigated to provide further direct evidence for the operation of a kick-out mechanism.
Adsorption trajectories and free-energy separatrices for colloidal particles in contact with a liquid-liquid interface
Authors: de Graaf Joost , Dijkstra Marjolein , van Roij René
Published: April 2010

We apply the recently developed triangular tessellation technique as presented by J. de Graaf et al. [Phys. Rev. E 80, 051405 (2009)] to calculate the free energy associated with the adsorption of anisotropic colloidal particles at a flat interface. From the free-energy landscape, we analyze the adsorption process, using a simplified version of Langevin dynamics. The present result is a first step towards understanding the time-dependent behavior of colloids near interfaces. This study shows a wide range of adsorption trajectories, where the emphasis lies on a strong dependence of the dynamics on the orientation of the colloid at initial contact with the interface. We believe that the observed orientational dependence in our simple model can be recovered in suitable experimental systems.
The multiscale coarse-graining method. VI. Implementation of three-body coarse-grained potentials
Authors: Larini Luca , Lu Lanyuan , Voth Gregory A.
Published: April 2010

Many methodologies have been proposed to build reliable and computationally fast coarse-grained potentials. Typically, these force fields rely on the assumption that the relevant properties of the system under examination can be reproduced using a pairwise decomposition of the effective coarse-grained forces. In this work it is shown that an extension of the multiscale coarse-graining technique can be employed to parameterize a certain class of two-body and three-body force fields from atomistic configurations. The use of explicit three-body potentials greatly improves the results over the more commonly used two-body approximation. The method proposed here is applied to develop accurate one-site coarse-grained water models.
Free energy wells for small gas bubbles in soft deformable materials
Authors: Goldman Saul
Published: April 2010

Thermodynamic expressions are derived for the system relative Gibbs free energy, and the relative Gibbs free energy per bubble, for all possible equilibrium bubble states that can form in a soft slightly rigid material, initially supersaturated with a dissolved inert gas (N2). While the thermodynamic manipulations are exact, the final expressions are approximate, due to an approximation made in deriving the expression for the elastic free energy of a soft material containing more than a single bubble. The expressions predict that provided the shear modulus of the soft material is not negligibly small, free energy wells which stabilize small gas bubbles for finite periods of time exist in such materials. This is consistent with a previous calculation, based solely on the bubble pressure equation, which resulted in the conjecture that bubbles found in soft materials with some rigidity (or shear resistance) are likely to be small. The possible relevance of this to the field of decompression sickness is outlined.
Anomalous magnetic field effects during pulsed injection metal-organic chemical vapor deposition of magnetite films
Authors: Zukova Anna , Teiserskis Arunas , Gun’ko Y. K. , Sánchez Ana M. , van Dijken Sebastiaan
Published: April 2010

We report on large external magnetic field effects during pulsed injection metal-organic chemical vapor deposition of magnetite films on MgO(001). The application of a 1 T field during the growth process significantly increases the saturation magnetization of magnetite by 150%–220% at a deposition temperature of 550 and 600 °C, while the enhancement of the remanent magnetization is even larger. This anomalous magnetic field effect does not drastically alter the crystalline texture, surface morphology, and film thickness of magnetite, but is explained by a suppression of antiphase-boundary formation during film growth.
Transport properties of corrugated graphene nanoribbons
Authors: Yu Zhizhou , Sun L. Z. , Zhang C. X. , Zhong J. X.
Published: April 2010

The transport properties of the devices made by corrugated graphene nanoribbons were investigated using the density functional theory in combination with the nonequilibrium Green’s function method. We find that the transport properties of the zigzag graphene nanoribbons (ZGNRs) with arched corrugation are similar to the flat one, while the transmission of the ZGNRs with step-shaped corrugation is greatly depressed. As for the armchair graphene nanoribbons (AGNRs), arched corrugation enlarges the transmission gap and the threshold voltage of the device. Moreover, the open currents of AGNRs are significantly depressed by both stepped and arched corrugation.
Large-area organic solar cells with metal subelectrode on indium tin oxide anode
Authors: Park Sun-Young , Jeong Won-Ik , Kim Do-Geun , Kim Jong-Kuk , Lim Dong Chan , Kim Joo Hyun , Kim Jang-Joo , Kang Jae-Wook
Published: April 2010

This study examined the effects of the electrode geometry combined with the cell area on the device performance. We systematically investigated the effects of cell area in organic solar cells (OSCs) by introducing of metal subelectrodes to reduce the resistive loss of indium tin oxide. The subelectrode defines the active area and works as the conducting electrode at the same time with very low resistance. The series resistance could be reduced significantly by using the subelectrode, yielding a power conversion efficiency of 2.6±0.3% up to the cell area of 4.08 cm2. This suggests that OSCs with subelectrode geometry can be used for evaluating new materials and processes with accurate measurements on the centimeter scale.
Adaptation to Combinations of form, Colour, and Movement
Authors: Burmester Alex , Broerse Jack
Published: April 2010

Observers typically report illusory colour on achromatic gratings after being adapted to orthogonally oriented gratings presented in complementary colours, where the colour apparent on each grating is complementary to the one that had been presented with that grating during adaptation (McCollough, 1965 Science149 1115–1116). We used this procedure, but presented homogenous fields at test instead of achromatic gratings. When adaptation stimuli moved in directions locally orthogonal to their orientation, we found that, for up to 7–8 min after adaptation, a flower-like illusory pattern was evident on both homogenous fields; after this time illusory radial lines and concentric circles were evident and were colour-contingent (eg for adaptation with green concentric circles and magenta radial lines, concentric circles were apparent on a magenta test field and radial lines were apparent on a green test field). When stimuli were stationary during induction, colour-contingent illusory forms were also apparent at test. The results demonstrate that an aftereffect, reciprocal to the McCollough effect, can be produced under appropriate induction conditions, and that this effect is not due to retinal afterimages.
Mechanistic basis for LQT1 caused by S3 mutations in the KCNQ1 subunit of IKs
Authors: Eldstrom Jodene , Xu Hongjian , Werry Daniel , Kang Congbao , Loewen Matthew E. , Degenhardt Amanda , Sanatani Shubhayan , Tibbits Glen F. , Sanders Charles , Fedida David
Published: April 2010

Long QT interval syndrome (LQTS) type 1 (LQT1) has been reported to arise from mutations in the S3 domain of KCNQ1, but none of the seven S3 mutations in the literature have been characterized with respect to trafficking or biophysical deficiencies. Surface channel expression was studied using a proteinase K assay for KCNQ1 D202H/N, I204F/M, V205M, S209F, and V215M coexpressed with KCNE1 in mammalian cells. In each case, the majority of synthesized channel was found at the surface, but mutant IKs current density at +100 mV was reduced significantly for S209F, which showed ∼75% reduction over wild type (WT). All mutants except S209F showed positively shifted V1/2’s of activation and slowed channel activation compared with WT (V1/2 = +17.7 ± 2.4 mV and τactivation of 729 ms at +20 mV; n = 18). Deactivation was also accelerated in all mutants versus WT (126 ± 8 ms at −50 mV; n = 27), and these changes led to marked loss of repolarizing currents during action potential clamps at 2 and 4 Hz, except again S209F. KCNQ1 models localize these naturally occurring S3 mutants to the surface of the helices facing the other voltage sensor transmembrane domains and highlight inter-residue interactions involved in activation gating. V207M, currently classified as a polymorphism and facing lipid in the model, was indistinguishable from WT IKs. We conclude that S3 mutants of KCNQ1 cause LQTS predominantly through biophysical effects on the gating of IKs, but some mutants also show protein stability/trafficking defects, which explains why the kinetic gain-of-function mutation S209F causes LQT1.
Stable ATP binding mediated by a partial NBD dimer of the CFTR chloride channel
Authors: Tsai Ming-Feng , Li Min , Hwang Tzyh-Chang
Published: April 2010

Cystic fibrosis transmembrane conductance regulator (CFTR), a member of the adenosine triphosphate (ATP) binding cassette (ABC) superfamily, is an ATP-gated chloride channel. Like other ABC proteins, CFTR encompasses two nucleotide binding domains (NBDs), NBD1 and NBD2, each accommodating an ATP binding site. It is generally accepted that CFTR’s opening–closing cycles, each completed within 1 s, are driven by rapid ATP binding and hydrolysis events in NBD2. Here, by recording CFTR currents in real time with a ligand exchange protocol, we demonstrated that during many of these gating cycles, NBD1 is constantly occupied by a stably bound ATP or 8-N3-ATP molecule for tens of seconds. We provided evidence that this tightly bound ATP or 8-N3-ATP also interacts with residues in the signature sequence of NBD2, a telltale sign for an event occurring at the NBD1–NBD2 interface. The open state of CFTR has been shown to represent a two-ATP–bound NBD dimer. Our results indicate that upon ATP hydrolysis in NBD2, the channel closes into a “partial NBD dimer” state where the NBD interface remains partially closed, preventing ATP dissociation from NBD1 but allowing the release of hydrolytic products and binding of the next ATP to occur in NBD2. Opening and closing of CFTR can then be coupled to the formation and “partial” separation of the NBD dimer. The tightly bound ATP molecule in NBD1 can occasionally dissociate from the partial dimer state, resulting in a nucleotide-free monomeric state of NBDs. Our data, together with other structural/functional studies of CFTR’s NBDs, suggest that this process is poorly reversible, implying that the channel in the partial dimer state or monomeric state enters the open state through different pathways. We therefore proposed a gating model for CFTR with two distinct cycles. The structural and functional significance of our results to other ABC proteins is discussed.
Changes in the Molecular Epidemiological Characteristics of Methicillin-ResistantStaphylococcus aureusin a Neonatal Intensive Care Unit
Authors: Carey Alison J. , Della-Latta Phyllis , Huard Richard , Wu Fann , Graham Phillip L. , Carp Diane , Saiman Lisa
Published: April 2010

Objective.

To determine whether the molecular epidemiological characteristics of methicillin-resistantStaphylococcus aureus(MRSA) had changed in a level III neonatal intensive care unit (NICU).

Design.

Retrospective review of medical records.

Setting.

Level III NICU of a university-affiliated children's hospital in New York, New York.

Patients.

Case patients were neonates hospitalized in the NICU who were colonized or infected with MRSA.

Methods.

Rates of colonization and infection with MRSA during the period from 2000 through 2008 were assessed. Staphylococcal chromosomal cassette (SCC)mecAanalysis and genotyping forS. aureusencoding protein A (spa) were performed on representative MRSA isolates from each clonal pulsed-field gel electrophoresis pattern.

Results.

Endemic MRSA infection and colonization occurred throughout the study period, which was punctuated by 4 epidemiologic investigations during outbreak periods. During the study period, 93 neonates were infected and 167 were colonized with MRSA. Surveillance cultures were performed for 1,336 neonates during outbreak investigations, and 115 (8.6%) neonates had MRSA-positive culture results. During 2001-2004, healthcare-associated MRSA clones, carrying SCCmectype II, predominated. From 2005 on, most MRSA clones were community-associated MRSA with SCCmectype IV, and in 2007, USA300 emerged as the principal clone.

Conclusions.

Molecular analysis demonstrated a shift from healthcare-associated MRSA (2001-2004) to community-associated MRSA (2005-2008).
Orally‐based information
Authors: Turner Deborah
Published: April 2010

Purpose

The purpose of this paper is to explore a new research area: orally‐based information.

Design/methodology/approach

The study utilizes a social constructionist approach. The social constructionist meta‐theory, which holds that contributions to knowledge can be made orally, frames it.

Findings

The paper explicates how orality, or word‐of‐mouth transactions, conveys information; describes approaches for investigating orally‐based information; and articulates the need for future information behavior investigations that focus on orality.

Research limitations/implications

The research exploration focuses on face‐to‐face oral data. It calls for increased attention to orally‐based information, and offers tentative suggestions for accomplishing this goal.

Practical implications

The results provide insight that assist in understanding how orally‐based information intersects with information behavior, knowledge management, information policy, cultural heritage, and professional development that involves orality.

Originality/value

The paper builds a theoretical foundation for increased understanding of the meaning and functions of orally‐based information.
RFID technology implementation in two libraries in New Delhi
Authors: Madhusudhan Margam
Published: April 2010

Purpose

The purpose of this paper is to examine the use and implementation of RFID technology at the Indian Law Institute Library and National Social Science Documentation Centre Library, New Delhi.

Design/methodology/approach

A survey was conducted at the two libraries, using a structured questionnaire comprising 20 questions.

Findings

It was found that after implementation of RFID in both the libraries the check‐in and check‐out time is reduced to less than 20 seconds per item, and use of the libraries has also increased. Neither library had calculated the saving of staff time by performing multiple check‐out and check‐in of items. High cost is the most significant challenge faced after implementation of RFID technology.

Originality/value

The paper provides the advantages of RFID technology for libraries and recommends this technology to other libraries for faster and better services to their users.
A report on the 30th Annual Conference of the International Association of Scientific and Technological University Libraries (IATUL)
Authors: Tripathi Manorama
Published: April 2010

Purpose

The paper aims to report on the 30th IATUL Annual Conference held in Leuven, Belgium, 1‐4 June, 2009

Design/methodology/approach

The paper summarises the major themes of the conference as well as giving some specific details of developments at the Indira Gandhi National Open University in India, which supplement the author's presentation at the conference.

Findings

The IATUL conference included a wide gamut of important issues faced by the libraries in the knowledge society of the twenty‐first century. The delegates exchanged ideas and learnt of best practices prevalent in libraries across the globe. The conference provided insights into the issues of innovation, change, benchmarking, quality assurance, Web 2.0 tools, information literacy, free internet resources and so forth.

Originality/value

It was a conference of immense value for library and information professionals. It raised important issues; problems faced by the libraries today and offered tentative solutions.
HRM in the Hungarian SME sector
Authors: Richbell Suzanne , Szerb László , Vitai Zsuzsanna
Published: April 2010

Purpose

This paper aims to provide an original picture of a selection of human resource management (HRM) activities in the micro, small and medium sized enterprises (SMEs) in Hungary and to explore the extent to which these activities can be related to variations in firm size and variations in firm performance.

Design/methodology/approach

The study measures the presence or absence of a selection of HRM activities through a questionnaire survey of a large sample of 678 Hungarian SMEs.

Findings

Hungarian SMEs, in their working relationships, are closer to the “happy family” model of the SME than the “bleak house” model. Employee morale was perceived as high and only one in ten SMEs felt their employees were opposed to change. Owners were reluctant to seek advice from those outside the firm. They also showed reluctance to discuss future plans with their employees although they did tend to consult employees who would be affected directly by any change. Communication within SMEs was predominantly informal. Surprisingly, given the skills shortages highlighted by SMEs in other economies, very few of the Hungarian SMEs identified skills shortages as a problem and formal training programmes were reported only rarely. Variations between micro, small and medium sized firms are highlighted to emphasize the heterogeneous nature of the Hungarian SME sector.

Research limitations/implications

The HRM activities considered provide a picture of only a small number of HRM activities in Hungarian SMEs but the findings imply the relationships examined here are deserving of further exploration both in Hungary and other transition economies.

Originality/value

The paper provides a detailed picture of selected aspects of HRM in smaller businesses within a transition economy.
Business continuity management in large construction companies in Singapore
Authors: Pheng Low Sui , Liu Junying , Sio Stephen
Published: April 2010

Purpose

The aim of this study is to determine whether large construction companies practise business continuity management (BCM), the type of crises which companies deem impactful for their organizations and their reactions to certain crises.

Design/methodology/approach

A survey of 22 large construction companies in Singapore was conducted.

Findings

The survey suggests that, although the importance and usefulness of having BCM are clear, the receptiveness of BCM among large construction firms is far from ideal. In today's unpredictable environment, there is a tendency for catastrophes to occur unexpectedly and to bring about undesired consequences. A large majority of the respondents did not have any form of BCM practices within their organization. This is mainly because they were unaware of what constitutes a business continuity plan.

Research limitations/implications

The survey was conducted only among large construction companies; as such, the results obtained cannot be used to represent the entire industry. However, focusing on the larger companies is strategically correct for a start, because BCM‐related initiatives, if any, tend to be undertaken by the larger companies, as they have the necessary resources, such as manpower and finance, to do so.

Practical implications

To be successful in promoting BCM in the building industry, the relevant authorities in Singapore, such as the Building and Construction Authority, should demonstrate to construction companies how beneficial BCM is for the company's operations, so that they can be better equipped to meet future challenges more confidently.

Originality/value

As with all other businesses, an effective business continuity plan is critical to companies in the construction industry. Being in an industry that is constantly subjected to internal and external pressure, construction companies are likely to incur costly errors if they are caught unprepared when a crisis strikes. This is the first ever study of BCM in the construction industry.
A method for action research interventions to improve joint problem solving in operational teams in the Swedish construction industry
Authors: Sunding Lars , Odenrick Per
Published: April 2010

Purpose

The purpose of this paper is to test an intervention technique developed earlier. The technique builds on an action research approach with a threefold aim: to produce change in a practical context, in our case to enhance the problem‐solving capacity in an operational team in an authentic construction project, and at the same time; test the technique and finally, extract additional knowledge about the problem area.

Design/methodology/approach

The technique is based on “the Skilled Facilitator” approach and the “krAft” concept, extended with knowledge about unconscious behaviour and focusing on counteracting counterproductive behaviour. The intervention was performed by the first author and studied through joint reflection, in part with the second author and in part with the participants, on documentation from meetings (notes and audio recordings), individual interviews, questionnaires, and observations.

Findings

The intervention technique developed was found to be effective in the aspect of creating efficient learning processes in the operational team. Results show that change occurred compared to the participants' experience from earlier construction projects, and indicates that the intervention was, at least partly, reason for the change. Even though the changes were apprehended both positive and negative, the positive changes were in the majority.

Originality/value

The paper creates new knowledge about how communication problems and other practical problems in the construction industry can be overcome with the help of an interventionist. The concept of the interventionist as a “liberator,” is introduced.
The relative importance of sector and regional factors in the hotel industry
Authors: Giannotti Claudio , Mattarocci Gianluca , Spinelli Luca
Published: April 2010

Purpose

The purpose of the paper is to compare the role of the sector and geographical features in explaining the performance of a hotel structure.

Design methodology/approach

The paper constructs a measure of net profit for available room (GOPPAR) for a representative sample of Italian hotels and uses a constrained linear regression model in order to identify the role of sectoral and geographical features. The analysis is released adopting a multiple cross sectional approach and considering not only the average role of sectoral and geographic characteristic, but also the time trend of relation inspected.

Findings

Results obtained show that the overall national trend is not significant for explaining the performance of each hotel. Considering geographical and sectoral features, the first of these explain better the disalignment of the performance respect to the national average.

Research limitations/implications

The paper proposes an analysis of the hotel industry using a standard geo‐sectoral classification. More data about the characteristics of the firms considered in the sample could allow to define a more detailed model that consider also other hotel features that could impact on the demand and supply of the service.

Practical implications

Results could be useful for the hotel chains and for institutional investors specialized in the hotel sector, in order to define a first guideline for the property selection process and diversification portfolio strategy.

Originality/value

The paper represents the first work that analyse the role of regional and sectoral factors in explaining the performance of the hotel industry and supports the thesis proposed with and empirical evidence on world leading market (Italy).
The strategic importance of tacit knowledge management activities in construction
Authors: Chen L. , Mohamed Sherif
Published: April 2010

Purpose

Tacit knowledge is perceived as the most strategically important resource of the construction organisation, and the only renewable and sustainable base for its activities and competitiveness. Knowledge management (KM) activities that deal with tacit knowledge are essential in helping an organisation to achieve its long‐term organisational objectives. The purpose of this paper is to provide empirical evidence for the stronger strategic role of tacit KM in comparison to explicit KM.

Design/methodology/approach

A questionnaire survey was administered in 2005 to a sample of construction contractors operating in Hong Kong to elicit opinions on the internal business environment, intensity of KM activities as executed by targeted organisations, and contribution of these activities to business performance (BP). A total of 149 usable responses were received from 99 organisations representing about 38 per cent of the sampling frame. The statistical analyses helped to map the reported KM activities into two groups that, respectively, deal with tacit and explicit knowledge. The sensitivity to variations of organisational policies and strength of association with BP in relation to the two groups of KM activities were also compared empirically. A total of 15 interviews with the managerial and professional staff of leading contractors was undertaken to provide insightful narratives of KM implementations.

Findings

The effective implementation of organisational policies, such as encouraging innovations and strengthening strategic guidance for KM, would facilitate human interactions of tacit KM. Higher intensity of activities in managing tacit knowledge would ultimately help the organisations to achieve economic gain in the long run.

Originality/value

The stronger strategic role of tacit KM is empirically investigated and established within the context of construction organisations.
The use of interorganisational ICT in construction projects: a critical perspective
Authors: Adriaanse Arjen , Voordijk Hans , Dewulf Geert
Published: April 2010

Purpose

The objective of this paper is to demonstrate how a critical perspective (i.e. critical social theory) can be applied to provide understanding and insights into mechanisms as to why interorganisational information communication technologies (ICT) in construction projects is not used in the intended way.

Design/methodology/approach

Habermas' critical social theory, in particular his models of action, is used for the critical analysis. From this perspective, the intended and actual use of document management and workflow management systems are studied in two construction projects.

Findings

In construction projects, interorganisational ICT is intended to support instrumental action, communicative action and sometimes also dramaturgical action. However, in practice, this ICT is not used in the intended way because actors adopt strategic action and normatively regulated action as well.

Research limitations/implications

The paper confirms the importance of analysing the social system and the technical system, and how these interact, to understand how and why actors use interorganisational ICT.

Originality/value

This paper demonstrates how a critical social theory provides insights into mechanisms as to why interorganisational ICT in construction projects is not used in the intended way.