bluuebunny/crossref_metadata_2025_split huggingface dataset:
Angular distribution of liquid droplets during the laser ablation of silicon target
Authors: Belaroussi Y. , Kerdja T. , Malek S. 
Published: March 2010

AbstractPulsed laser deposition of thin films involves an extremely complex process, and therefore, the study of the different aspects of the basic mechanism of laser ablation is still under investigation and development.In this work, the initial stages of laser ablation process have been studied by considering the roughness of the deposited surfaces, their continuous morphological changes and the angular distribution of liquid droplets produced by laser irradiation.Various experiments on silicon wafers, using a KrF excimer laser (248 nm) impinging at 45° with respect to the target were performed. Scanning electron microscopy technique was used to investigate the morphological changes of the silicon surface and the angular emission distribution of the liquid droplets. Copyright © 2010 John Wiley & Sons, Ltd.
Auger electron spectroscopy and X‐ray photoelectron spectroscopy study of the electron‐stimulated surface chemical reaction mechanism for phosphor degradation
Authors: Swart H. C. , Terblans J. J. , Coetsee E. , Kumar Vinay , Ntwaeaborwa O. M. , Dhlamini M. S. , Dolo J. J. 
Published: March 2010

AbstractPhosphors normally lose brightness upon bombardment with electron, ion or photon beams. A combination of techniques such as X‐ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and cathodoluminescence (CL) spectroscopy was used to show that the main reason for the degradation in luminescent intensity under electron bombardment is the formation of a non‐luminescent layer on the surface due to an electron‐stimulated surface chemical reaction (ESSCR). The decrease in luminance was found to be a result of the growth of the ‘dead layer’. Different phosphors which include sulfide‐based as well as oxide‐based phosphors reacted similarly under electron bombardment. The formation of an altered layer (oxide layer) on the surface of the different phosphors leads to the decrease of the luminescent intensity at that specific wavelength and in some cases to an increase of the intensity at another wavelength. The mechanisms of the degradation of several rare earth and transition metal phosphors are discussed in detail. Copyright © 2010 John Wiley & Sons, Ltd.
Investigating the surface properties of polymer‐coated clay by IGC
Authors: Topaloǧlu Yazıcı Demet 
Published: March 2010

AbstractThis paper deals with understanding the surface behaviors of calcined clay and the organic/inorganic system. The surface properties like the adsorption thermodynamic parameters and the dispersive component of the surface energy were determined by the adsorption of n‐alkanes on the solids that were the subject of interest, i.e. calcined sepiolite and polystyrene coated calcined sepiolite. Inverse gas chromatography (IGC) was used for this purpose. The dispersive component of the surface energy of system lies between the members of system. Additionally Diffuse Reflectance Infrared Fourier Transform (DRIFT) technique was used to record the functional groups of solids. Copyright © 2010 John Wiley & Sons, Ltd.
Non‐destructive investigation of fibronectin adsorption on titanium surfaces using PM‐RAIRS: effect of surface hydroxylation
Authors: Boudesocque Stéphanie , Dargaud Olivier , Stievano Lorenzo , Méthivier Christophe , Lambert Jean‐François , Coradin Thibaud , Pradier Claire‐Marie 
Published: March 2010

AbstractPolarisation‐modulation reflection‐absorption infrared spectroscopy (PM‐RAIRS) is a useful non‐destructive technique to study semi‐quantitatively the adsorption of proteins on metal surfaces. In this work, we employed PM‐RAIRS to study the effect of the degree of hydroxylation of the surface of titanium metal sheets, obtained by specific acidic or basic treatments, on the adsorption of fibronectin, a model plasma adhesion protein. Our results seem to indicate that the degree of hydroxylation does not influence significantly the adhesion properties of fibronectin, which is one of the main steps in titanium osseointegration process. Copyright © 2010 John Wiley & Sons, Ltd.
Comparison of surface activation processes for protein immobilization on plasma‐polymerized acrylic acid films
Authors: Strola S. , Ceccone G. , Gilliand D. , Valsesia A. , Lisboa P. , Rossi F. 
Published: March 2010

AbstractIn this work, quartz crystal microbalance (QCM) crystal surfaces were analyzed in order to study the behavior of protein attachment on fouling substrates. In this context, covalent and noncovalent immobilization of different proteins [bovine serum albumin (BSA), collagen] has been investigated. For the noncovalent immobilization, silicon dioxide‐coated QCM crystals were used, while the covalent immobilization was obtained via plasma‐polymerized acrylic acid film (ppAA) deposited onto the QCM substrates. Two different activation processes, namely, reaction with trifluoroacetic anhydride (TFAA) and 1‐ethyl‐3,3‐dimethyl carbodiimide (EDC) and N‐hydroxysuccinimide (NHS), were studied.After the QCM experiments, all samples were analyzed with X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry to gain information on the surface chemistry and composition. The results indicate that the protein adsorption process depends on protein concentration, whereas the complement activation effectiveness depends on protein type. In particular, for BSA, XPS and QCM data show a greater immobilization in the case of EDC/NHS activation compared to the TFAA, whereas in the case of collagen, only the EDC/NHS activation was able to yield covalent coupling. Copyright © 2010 John Wiley & Sons, Ltd.
First‐principle studies of dissociative adsorption of H2O on NiAl(110)‐(2 × 2) surface
Authors: Evecen M. , Çakmak M. 
Published: March 2010

AbstractA theoretical study of the interaction of H2O with NiAl(110) surface has been carried out with density functional theory. We have studied that H2O molecule dissociates into OH and H on NiAl(110). We have assumed four possible locations for OH and H on the NiAl(110) surface. The minimum energy for OH molecule and H atom is at the 2AlNi site, but H atom towards a near by surface Ni atom, with the adsorption energy −0.79 eV. Bond length and bond angle of H2O molecule were found to be 0.99 Å and 103.9°, respectively, which are close to gas phase theoretical (exp.) values 0.97 Å (0.96 Å) and 104.8° (104.5° ). The calculated bond length between O and Al (H) is 1.97 Å (0.98 Å). Bond length between H and Ni is found to be 1.55 Å. We have also presented the reaction path for OHH on NiAl(110) surface. Copyright © 2010 John Wiley & Sons, Ltd.
The effect of temperature on interfacial characteristics of fiber cord/rubber composite in the pull‐out process
Authors: Fang Qing‐Hong , Wang Hui‐Bin , Huang Bao‐Zong 
Published: March 2010

AbstractThe test of fiber pullout from rubber was carried out under different conditions, at three temperatures. Based on the experiment and a nonlinear two‐dimensional finite element (2D FE) modeling, the single fiber cord pullout from the rubber matrix at different temperatures was analyzed. The changes of interfacial shear stresses and failure mode at every stage of interface cracking forthe fiber cord/rubber composite were also investigated. It is shown that the simulation results of the pullout are in good agreement with the experiment. It is concluded that the 2D FE modeling can effectively predict the thermal interface cracking process for an axisymmetric structure of the fiber cord/rubber composite. Copyright © 2010 John Wiley & Sons, Ltd.
Determination of atomic Ni interaction with TiO2 by XPS
Authors: Pan J. S. , Tao J. G. , Huan C. H. A. , Chiam S. Y. , Zhang Z. , Li D. T. H. , Sun Y. , Chai J. W. , Wang S. J. , Sun Chang Q. 
Published: March 2010

AbstractIt is impossible to directly measure the photoelectron spectrum of an atom using conventional XPS due to its low detection sensitivity. In this work, an indirect method has been developed to determine the binding energy (BE) of an atom. In this method, the BE of the atom can be obtained by extrapolation of the experimental BE curves with atomic deposition coverage to zero coverage. With this method, the Ni 2p3/2 BE's of atomic Ni on TiO2(001) and (110) surfaces are deduced to be 853.69 and 853.55 eV, respectively. Compared with atomic Ni in gas phase, relaxation shifts of 7.34 and 7.48 eV are obtained on TiO2(001) and (110) surfaces, respectively. These values are very close to the relaxation shift of 7.3 eV due to d electron screening, indicating d‐like screening effects from the TiO2 substrates after Ni 2p photoionization. This method is also used to determinate the Ni 2p3/2 BE's of atomic Ni on TiO2(001) with different surface stoichiometries. The difference of Ni 2p3/2 BE is due to different interfacial charge transfer. Copyright © 2010 John Wiley & Sons, Ltd.
A Bayesian approach to competing risks analysis with masked cause of death
Authors: Sen Ananda , Banerjee Mousumi , Li Yun , Noone Anne‐Michelle 
Published: March 2010

AbstractCause‐specific analyses under a competing risks framework have received considerable attention in the statistical literature. Such analyses are useful for comparing mortality patterns across racial and/or age groups. Earlier work in the statistical literature focused on the situation when the cause of death is known. A challenging twist to the problem arises when the cause of death is not known exactly, but can be narrowed down to a set of potential causes that do not necessarily act independently. This phenomenon, referred to asmasking, is often the result of incomplete or partial information on death certificates and/or lack of routine autopsy on every patient. In this article we propose a semiparametric Bayesian approach for analyzing competing risks survival data with masked cause of death. The models proposed do not assume independence among the causes, and are valid for an arbitrary number of causes. Further, the Bayesian approach is flexible in allowing a general pattern of missingness for the cause of death. We illustrate our methodology using breast cancer data from the Detroit Surveillance, Epidemiology, and End Results registry. Copyright © 2010 John Wiley & Sons, Ltd.
Approximate inference for disease mapping with sparse Gaussian processes
Authors: Vanhatalo Jarno , Pietiläinen Ville , Vehtari Aki 
Published: March 2010

AbstractGaussian process (GP) models are widely used in disease mapping as they provide a natural framework for modeling spatial correlations. Their challenges, however, lie in computational burden and memory requirements. In disease mapping models, the other difficulty is inference, which is analytically intractable due to the non‐Gaussian observation model. In this paper, we address both these challenges. We show how to efficiently build fully and partially independent conditional (FIC/PIC) sparse approximations for the GP in two‐dimensional surface, and how to conduct approximate inference using expectation propagation (EP) algorithm and Laplace approximation (LA). We also propose to combine FIC with a compactly supported covariance function to construct a computationally efficient additive model that can model long and short length‐scale spatial correlations simultaneously. The benefit of these approximations is computational. The sparse GPs speed up the computations and reduce the memory requirements. The posterior inference via EP and Laplace approximation is much faster and is practically as accurate as via Markov chain Monte Carlo. Copyright © 2010 John Wiley & Sons, Ltd.
Radiosynthesis of the candidate β‐amyloid radioligand [11C]AZD2184: Positron emission tomography examination and metabolite analysis in cynomolgus monkeys
Authors: Andersson Jan D. , Varnäs Katarina , Cselényi Zsolt , Gulyás Balázs , Wensbo David , Finnema Sjoerd J. , Swahn Britt‐Marie , Svensson Samuel , Nyberg Svante , Farde Lars , Halldin Christer 
Published: March 2010

Abstractβ‐Amyloid accumulation is associated with the pathogenesis of Alzheimer's disease (AD). AZD2184, a new radioligand for high‐contrast positron emission tomography (PET) imaging of Aβ‐deposits, has recently been developed and characterized in vitro and in rodents ex vivo. The objective of this study was to label AZD2184 with carbon‐11, to perform in vivo characterization of [11C]AZD2184 ([11C]5) in the cynomolgus monkey brain as well as whole‐body dosimetry, and to examine the metabolism of the labeled radioligand. [11C]5 was prepared by a two‐step radiosynthesis starting with the reaction of 5‐(6‐(tert‐butyldimethylsilyloxy)benzo[d]thiazol‐2‐yl)pyridin‐2‐amine with [11C]methyl iodide followed by deprotection using water. Four brain PET measurements in two cynomolgus monkeys and one whole‐body PET measurement were performed with [11C]5. There was a high and rapid brain uptake (2.2–3.4% of injected dose at 2 min). The distribution of brain radioactivity was fairly uniform, with early to late‐brain concentration ratios (peak vs. 60 min) higher for [11C]5 than ratios previously reported for [11C]PIB (8.2 and 4.6, respectively). Based on the whole‐body data, it was estimated that an effective dose in an adult male would be 6.2 μSv/MBq and thus would be safe from a radiation point of view for multiple scans within the same year. [11C]5 shows binding characteristics, suggesting low levels of white‐matter retention, and may thus provide improved contrast when compared with currently used PET radioligands for visualization of Aβ‐deposits. On the basis of the labeling chemistry and the results of the biological evaluation, we conclude that [11C]5 should be useful for routine clinical studies. Synapse 64:733–741, 2010. © 2010 Wiley‐Liss, Inc.
(+)‐Methamphetamine‐induced monoamine reductions and impaired egocentric learning in adrenalectomized rats is independent of hyperthermia
Authors: Herring Nicole R. , Gudelsky Gary A. , Vorhees Charles V. , Williams Michael T. 
Published: March 2010

AbstractMethamphetamine (MA) is widely abused and implicated in residual cognitive deficits. In rats, increases in plasma corticosterone and egocentric learning deficits are observed after a 1‐day binge regimen of MA (10 mg/kg × 4 at 2‐h intervals). The purpose of this experiment was to determine if adrenal inactivation during and following MA exposure would attenuate the egocentric learning deficits in the Cincinnati water maze (CWM). In the first experiment, the effects of adrenalectomy (ADX) or sham surgery (SHAM) on MA‐induced neurotoxicity at 72 h were determined. SHAM‐MA animals showed typical patterns of hyperthermia, whereas ADX‐MA animals were normothermic. Both SHAM‐MA‐ and ADX‐MA‐treated animals showed increased neostriatal glial fibrillary acidic protein and decreased monoamines in the neostriatum, hippocampus, and entorhinal cortex. In the second experiment, SHAM‐MA‐ and ADX‐MA‐treated groups showed equivalently impaired CWM performance 2 weeks post‐treatment (increased latencies, errors, and start returns) compared to SHAM‐saline (SAL) and ADX‐SAL groups with no effects on novel object recognition, elevated zero maze, or acoustic startle/prepulse inhibition. Post‐testing, monoamine levels remained decreased in both MA‐treated groups in all three brain regions, but were not as large as those observed at 72‐h post‐treatment. The data demonstrate that MA‐induced learning deficits can be dissociated from drug‐induced increases in plasma corticosterone or hyperthermia, but co‐occur with dopamine and serotonin reductions. Synapse 64:773–785, 2010. © 2010 Wiley‐Liss, Inc.
Different chronic cocaine administration protocols induce changes on dentate gyrus plasticity and hippocampal dependent behavior
Authors: Perez M.F. , Gabach L.A. , Almiron R.S. , Carlini V.P. , De Barioglio S.R. , Ramirez O.A. 
Published: March 2010

AbstractHippocampus is a limbic structure that participates in learning and memory formation. Specifically the dentate gyrus has been described as a hippocampal subregion with high rates of plasticity and it is targeted by different psychoactive drugs modulating synaptic plasticity. Repeated cocaine administration induces sensitization to the locomotor effects and it is believed that sensitization involves the same mechanisms of drug seeking and relapse. Although, the mechanisms underlying sensitization is not fully understood. In this work we investigated the impact of repeated intraperitoneal administration of cocaine (15 or 20 mg/kg/day along 5 or 15 days respectively; and 15 mg/kg/day along 5 day followed by a challenge dose after three days of withdrawal) on the dentate gyrus synaptic plasticity, differentiating between sensitized and nonsensitized rats. Furthermore, we correlated changes on the hippocampal synaptic plasticity to memory retention. Our results revealed that the prevalence of cocaine sensitization (around 50%) was identical in all protocols used. The results found in the threshold to generate LTP were similar for all protocols used, being the threshold values cocaine‐treated groups (sensitized and nonsensitized) significantly reduced compared to controls, observing the highest reduction in the sensitized group. Moreover, we observed a facilitated retention of recent memory formation only in sensitized animals the nonsensitized subjects remained at the control levels. In conclusion, sensitization to cocaine generates a high efficiency of hippocampal synaptic plasticity that may underlie the aberrant engagement of learning processes occurred during drug addiction. Synapse 64:742–753, 2010. © 2010 Wiley‐Liss, Inc.
Stability analysis of the tip vortices of a wind turbine
Authors: Ivanell Stefan , Mikkelsen Robert , Sørensen Jens N. , Henningson Dan 
Published: March 2010

AbstractThe aim of the present paper is to obtain a better understanding of the stability properties of wakes generated by wind turbine rotors. To accomplish this, a numerical study on the stability of the tip vortices of the Tjaereborg wind turbine has been carried out. The numerical model is based on large eddy simulations of the Navier–Stokes equations using the actuator line method to generate the wake and the tip vortices. To determine critical frequencies, the flow is disturbed by inserting harmonic perturbations, giving rise to spatially developing instabilities. The results show that the instability is dispersive and that growth arises only for some specific frequencies and type of modes, in agreement with previous instability studies. The result indicates two types of modes; one where oscillations of neighboring vortex spirals are out of phase and one where oscillations in every vortex spiral in phase. The mode with spirals out of phase results in the largest growth with the main extension of the disturbance waves in radial and downstream directions. The out‐of‐phase disturbance leads to vortex pairing once the development leaves the linear stage. The study also provides evidence of a relationship between the turbulence intensity and the length of the near wake. The relationship, however, needs to be calibrated against measurements. Copyright © 2010 John Wiley & Sons, Ltd.
Transportable EDXRF analysis of environmental water samples using Amberlite IRC748 ion‐exchange preconcentration
Authors: Heiden E. S. , Gore D. B. , Stark S. C. 
Published: March 2010

AbstractTransportable energy‐dispersive X‐ray fluorescence spectrometers allow on‐site assessment of metal‐contaminated soils, sediments and other solids. Multi‐element analysis of liquid samples, such as surface water, groundwater, acid leach and aqueous soil extracts, would enhance on‐site environmental assessments. However, transportable spectrometers typically have detection limits for metals in waters of approximately 1–10 mg l−1, whereas many toxic elements are regulated at concentrations of 1–100 µg l−1. If detection limits for this technique can be lowered, then only one analytical tool, a transportable XRF spectrometer, may be sufficient for remote areas, increasing program flexibility and reducing the amount of equipment that needs to be purchased, transported and operated. This research develops an in‐field preconcentration technique using Amberlite IRC748 cation‐exchange resin, followed by XRF analysis of Fe, Ni, Cu, Zn and Pb at µg l−1 concentrations in aqueous samples. The operational parameters tested to maximise analyte recovery included flow rate, and the mass and chemical form of the resin. The method was tested with extracts from landfill soils and surface waters from a derelict base metal mine. The method recovered Cu, Zn and Pb accurately, and Ni and Fe at concentrations satisfactory for screening purposes. Copyright © 2010 John Wiley & Sons, Ltd.
Comparison of three portable EDXRF spectrometers for pigment characterization
Authors: Bonizzoni Letizia , Caglio Simone , Galli Anna , Poldi Gianluca 
Published: March 2010

AbstractIn the field of cultural heritage analyses, energy dispersive X‐ray fluorescence is a well known nondestructive technique used—among other applications—to characterize pigments and inks in artifacts such as paintings, polychromous sculptures and illuminated manuscripts. In this paper, we report on the performance of three portable X‐ray fluorescence analyzers currently used for laboratory or in situ analyses. The three spectrometers have been tested in laboratory on paint layers prepared to simulate real ones, with the specific goal to determine advantages and disadvantages for each instrument in the detection of specific elements characterizing the pigment. Additionally, overall general advantages and limitations of each system in practical use are highlighted. Copyright © 2010 John Wiley & Sons, Ltd.
Investing in Success: Key Strategies for Building Quality in After‐School Programs
Authors: Sheldon Jessica , Arbreton Amy , Hopkins Leigh , Grossman Jean Baldwin 
Published: March 2010

AbstractThis paper examines the relation between the implementation quality of after‐school literacy activities and student reading gains. The data are from an evaluation of a multi‐site after‐school program in California in which continuous program quality improvement strategies were implemented to improve the delivery of a new balanced literacy program. Strategies included: (1) targeted staff training throughout the year, (2) regular observations and coaching of staff, and (3) the use of data to measure progress. Programs struggled to successfully implement these strategies early in the initiative, but gradually improved the quality and consistency of their use. Program quality, as measured through observations, also increased. Results suggested that the size of student reading gains were positively correlated with the quality of literacy programming provided by each instructor.