bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of alloy elements on selective oxidation and galvanizability of TRIP‐aided steel
Authors: Liu Huachu , Shi Wen , He Yanlin , Li Lin 
Published: May 2010

AbstractThe galvanizability of four transformation‐induced plasticity‐aided steels was investigated. It was shown that steels with low Si and low Mn were well galvanized, and the effective Al in zinc bath may contribute to improve the galvanizability. At the same time, Thermo‐Calc, a commercial software for calculating thermodynamics, was employed to investigate the effect of alloy elements (Al, Mn and Si in the steel matrix) on selective oxidation that occurs in continuous hot‐dip galvanizing. It was found that the types and amounts of oxides were greatly influenced by these alloy elements. Similar to a Mn/Si ratio for SiMn steels, an Al/Mn ratio for AlMn steels was proposed in this article. Copyright © 2010 John Wiley & Sons, Ltd.
MEIS and ToF‐SIMS analyses of organic ultrathin films for absolute quantification of functional groups
Authors: Min Hyegeun , Moon Dae Won , Lee Tae Geol 
Published: May 2010

AbstractComplementary use of medium‐energy ion‐scattering spectroscopy (MEIS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) analyses was proposed as a new methodology for absolute quantification of functional groups in organic ultrathin films. First, MEIS analysis was used to determine the absolute areal densities of Ru dye molecules in organic ultrathin films, which were made by spin coating Ru 535‐bis TBA (C58H86O8N8S2Ru) solutions with varying concentrations. The thicknesses of the films were less than 2 nm each and the densities of these ultrathin layers were linearly correlated with the solution concentrations. The determined absolute areal densities of the Ru organic molecules were then used to calculate the areal densities of the stoichiometric functional groups. Secondly, the ToF‐SIMS intensities of the characteristic peaks such as Ru+, C16H35N+, CO2−, CSN−, CSNRu−, etc, associated with the functional groups of a Ru 535‐bis TBA molecule were correlated by the densities of the Ru organic molecules. Our results show that the correlation curves obtained through the complementary use of MEIS and ToF‐SIMS techniques could be useful to quantify functional groups on organic ultrathin films. Copyright © 2010 John Wiley & Sons, Ltd.
A systematic evaluation of cytospinning as a novel technique for the preparation of cells for ToF‐SIMS analysis
Authors: Jackson E. R. J. , Vickerman J. C. , Lockyer N. P. 
Published: May 2010

AbstractIn this paper we present a study focusing on the preparation of prostate cancer cell (PC‐3) nuclei and cervical cancer cells (Hela‐M) for ToF‐SIMS imaging. We evaluate cytospinning as a novel preparatory technique through comparisons with air drying, freeze drying, and freeze‐fracturing protocols and variations thereof. Using image contrast, assessing spectra for the loss, or gain of native and non‐native chemistry and relative organic and inorganic ion yields, the investigation provides a systematic evaluation of the features of each preparation technique. From this, cytospinning is shown to be a robust technique for the preparation of biological specimens from suspension. Using this technique, despite inconclusive SEM and SIMS images, it is likely the natural biochemistry and architecture was preserved, enabling accurate chemical localization. Copyright © 2010 John Wiley & Sons, Ltd.
Trap characterization in AlGaN/GaN HEMT by analyzing frequency dispersion in capacitance and conductance
Authors: Semra L. , Telia A. , Soltani A. 
Published: May 2010

AbstractAn analysis of frequency dispersion in capacitance and conductance of gate‐source contact of AlGaN/GaN HEMT was performed. Capacitance and conductance were measured at temperatures varying from 83 K to 370 K with bias voltage maintained at 0 V. In order to characterize trap states the conductance method was used considering series resistance. Hence, the parallel conductance Gp and capacitance Cp were calculated, and consequently interface trap density Dit and time constant t are deduced. The analysis is performed assuming a continuum of levels yielding to a trap density of approximately 10+12 cm−2eV−1 and a time constant varying between 1 µs and 3 ms. Activation energies and capture cross sections of three trap levels were deduced and their values were respectively (ΔEa1 = 0.201 eV, σn1 = 4.992 × 10−18 cm2), (ΔEa2 = 0.053 eV, σn2 = 2.585 × 10−21 cm2), (ΔEa3 = 0.121 eV, σn3 = 1.256 × 10−20 cm2). An electrical model was established with two levels of traps at AlGaN/GaN interface and one level located in barrier AlGaN surface. Copyright © 2010 John Wiley & Sons, Ltd.
Electronic structure of self‐assembled Sm nanostructure on HOPG studied by in‐situ photoemission spectroscopy and scanning probe microscopy
Authors: Kutluk G. , Nakatake M. , Sumuda H. , Namatame H. , Taniguchi M. 
Published: May 2010

AbstractIn‐situ photoemission spectroscopy of Sm over‐layer on HOPG in the coverage regime of 0.3∼10.0 Å has been performed at room temperature in the 4d–4f resonance energy region by using monochromatic synchrotron radiation light. Based on analysis of the spectra taken at hν = 134 eV (close to divalent samarium resonance), it is indicated that the divalent feature predominates the valence band spectra for the coverage below than 1.0 Å, while the trivalent structures are enhanced for Sm over‐layer coverage higher than the 1.0 Å. However, in the case of valence band spectra are excited with the photon of energy of 141 eV at trivalent samarium resonance, the trivalent feature dominates the spectra across over the 0.6∼10.0 Å coverage of Sm over‐layer. The mixed valence in the present Sm over‐layer system might be heterogeneous in nature. Our first result indicates that the VUV irradiation of Sm makes an important role for stimulating the degeneration of divalent multi‐configuration during the vacuum ultraviolet photoemission spectroscopy. Copyright © 2010 John Wiley & Sons, Ltd.
SIMS fingerprint analysis on organic substrates
Authors: Hinder Steven J. , Watts John F. 
Published: May 2010

AbstractToF‐SIMS has been used in the analysis of latent fingerprints (dactyloscopy) with a view to its use in forensic and biomedical applications. Szynkowska et al. have demonstrated that SIMS can be employed to produce images of whole fingerprints on inorganic surfaces such as steel, brass and glass.1 We demonstrate the detection of a range of exogenous materials in fingerprints including industrial lubricants, personal care products and pharmaceuticals on organic surfaces. We demonstrate fingerprint image acquisition on model substrate materials such as Si wafer and on more ‘difficult’ organic substrates such as polymeric coatings, paper and printed card.SIMS images, even when acquired at low resolution, clearly delineate those regions associated with the underlying substrate materials and those from the latent fingerprint. Fingerprint images acquired by SIMS imaging are capable of visualizing the minutiae associated with fingerprints with high resolution. Such minutiae are the key latent fingerprint features that must be visualized so that a forensic fingerprint examiner may make an identification. Copyright © 2010 John Wiley & Sons, Ltd.
Distributed lag non‐linear models
Authors: Gasparrini A. , Armstrong B. , Kenward M. G. 
Published: May 2010

AbstractEnvironmental stressors often show effects that are delayed in time, requiring the use of statistical models that are flexible enough to describe the additional time dimension of the exposure–response relationship. Here we develop the family of distributed lag non‐linear models (DLNM), a modelling framework that can simultaneously represent non‐linear exposure–response dependencies and delayed effects. This methodology is based on the definition of a ‘cross‐basis’, a bi‐dimensional space of functions that describes simultaneously the shape of the relationship along both the space of the predictor and the lag dimension of its occurrence. In this way the approach provides a unified framework for a range of models that have previously been used in this setting, and new more flexible variants. This family of models is implemented in the package dlnm within the statistical environment R. To illustrate the methodology we use examples of DLNMs to represent the relationship between temperature and mortality, using data from the National Morbidity, Mortality, and Air Pollution Study (NMMAPS) for New York during the period 1987–2000. Copyright © 2010 John Wiley & Sons, Ltd.
Efforts to adjust for confounding by neighborhood using complex survey data
Authors: Brumback Babette A. , Dailey Amy B. , He Zhulin , Brumback Lyndia C. , Livingston Melvin D. 
Published: May 2010

AbstractIn social epidemiology, one often considers neighborhood or contextual effects on health outcomes, in addition to effects of individual exposures. This paper is concerned with the estimation of an individual exposure effect in the presence of confounding by neighborhood effects, motivated by an analysis of National Health Interview Survey (NHIS) data. In the analysis, we operationalize neighborhood as the secondary sampling unit of the survey, which consists of small groups of neighboring census blocks. Thus the neighborhoods are sampled with unequal probabilities, as are individuals within neighborhoods. We develop and compare several approaches for the analysis of the effect of dichotomized individual‐level education on the receipt of adequate mammography screening. In the analysis, neighborhood effects are likely to confound the individual effects, due to such factors as differential availability of health services and differential neighborhood culture. The approaches can be grouped into three broad classes: ordinary logistic regression for survey data, with either no effect or a fixed effect for each cluster; conditional logistic regression extended for survey data; and generalized linear mixed model (GLMM) regression for survey data. Standard use of GLMMs with small clusters fails to adjust for confounding by cluster (e.g. neighborhood); this motivated us to develop an adaptation. We use theory, simulation, and analyses of the NHIS data to compare and contrast all of these methods. One conclusion is that all of the methods perform poorly when the sampling bias is strong; more research and new methods are clearly needed. Copyright © 2010 John Wiley & Sons, Ltd.
Estimation of overall survival in an ‘illness–death’ model with application to the vertical transmission of HIV‐1
Authors: Frydman Halina , Szarek Michael 
Published: May 2010

AbstractWe derive a nonparametric maximum likelihood estimate of the overall survival distribution in an illness–death model from interval censored observations with unknown status of the nonfatal event. This expanded model is applied to the re‐analysis of data from a randomized trial where infants, born to women infected with HIV‐1 that were randomly assigned to breastfeeding or counseling for formula feeding, were followed for 24 months for HIV‐1 positivity, HIV‐1‐free survival, and overall survival. HIV‐1 positivity, assessed by postpartum venous blood tests, is the interval censored nonfatal event, and HIV‐1 positivity status is unknown for a subset of infants due to periodic assessment. The analysis demonstrates that estimation of the overall and the pre‐ and post‐nonfatal event survival distributions with the proposed methods provide novel insights into how overall survival is influenced by the occurrence of the nonfatal event. More generally, it suggests the usefulness of this expanded illness–death model when evaluating composite endpoints as potential surrogates for overall survival in a given disease setting. Copyright © 2010 John Wiley & Sons, Ltd.
A spatial scan statistic for multinomial data
Authors: Jung Inkyung , Kulldorff Martin , Richard Otukei John 
Published: May 2010

AbstractAs a geographical cluster detection analysis tool, the spatial scan statistic has been developed for different types of data such as Bernoulli, Poisson, ordinal, exponential and normal. Another interesting data type is multinomial. For example, one may want to find clusters where the disease‐type distribution is statistically significantly different from the rest of the study region when there are different types of disease. In this paper, we propose a spatial scan statistic for such data, which is useful for geographical cluster detection analysis for categorical data without any intrinsic order information. The proposed method is applied to meningitis data consisting of five different disease categories to identify areas with distinct disease‐type patterns in two counties in the U.K. The performance of the method is evaluated through a simulation study. Copyright © 2010 John Wiley & Sons, Ltd.
Multidimensional standard curve for the development process of human fetuses
Authors: Naito K. , Udagawa J. , Otani H. 
Published: May 2010

AbstractThe present paper considers a multidimensional view of the standard for the development process of human fetuses. An efficient method by which to find a multidimensional standard curve for the development process of human fetuses is proposed in which a logistic function with three parameters is utilized as an underlying model and a nonlinear regression method is applied. The proposed method also identifies an approximate prediction region, which can be efficiently applied to diagnose fetal malformation. Copyright © 2010 John Wiley & Sons, Ltd.
Document‐centric XML workflows with fragment digital signatures
Authors: Brooke Phillip J. , Paige Richard F. , Power Christopher 
Published: May 2010

AbstractThe use of digital document management and processing is increasing. Traditional workflows of paper forms are being replaced by electronic workflows of digital documents. These workflows often require multiple signatures to be added to the documents for authorization and/or integrity. We describe examples of digital workflows that illustrate problems with digital signatures: i.e. the use of digital signatures across entire documents results in signatures that can be unnecessarily invalidated by subsequent modification of the document. We propose the use of fragment signatures, which reduce unnecessary invalidation of signatures and enable greater concurrency in workflows. Our approach is document‐centric and does not use a centralized database. We report on an implementation that allows fragment signatures over document fragments as well as the attachment (or embedding) of other documents. This allows collaborative or cooperative editing to occur on parts of a document without disturbing unrelated signatures. We describe the lessons learned from our deployments and offer further ways to embed such signatures into other document types. Copyright © 2010 John Wiley & Sons, Ltd.
An 802.11 MAC layer covert channel
Authors: Calhoun Telvis E. , Cao Xiaojun , Li Yingshu , Beyah Raheem 
Published: May 2010

AbstractFor extremely sensitive applications, it may be advantageous for users to transmit certain types of data covertly over the network. This provides an additional layer of security to that provided by the different layers of the protocol stack. In this paper we present a covert side channel that uses the 802.11 MAC rate switching protocol. The covert channel provides a general method to hide communications within currently deployed 802.11 LANs. The technique uses a one‐time password (OTP) algorithm to ensure high‐entropy randomness of the covert messages. We investigate how the covert side channel affects network throughput under various rate‐switching conditions with UDP‐based and TCP‐based application traffic. We also investigate the covertness of the covert side channel using standardized entropy. The theoretical analysis shows that the maximum covert channel bandwidth is 60 bps. The simulation results show that the impact on network throughput is minimal and increases slightly as the covert channel bandwidth increases. We further show that the channel has 100% accuracy with minimal impact on rate switching entropy for scenarios where rate switching normally occurs. Finally, we present two applications for the covert channel: covert authentication and covert WiFi botnets. Copyright © 2010 John Wiley & Sons, Ltd.
Understanding genetic, neurophysiological, and experiential influences on the development of executive functioning: the need for developmental models
Authors: Bruce Morton J. 
Published: May 2010

AbstractFlexibility is a cornerstone of adaptive behavior and is made possible by a family of processes referred to collectively as executive functions. Executive functions vary in efficacy from individual to individual and also across developmental time. Infants and young children, for example, have difficulty flexibly adapting their behavior, and often repeat actions that are no longer appropriate. And although older children do not typically make such striking errors, they have more difficulty exercising control than adolescents and adults. Such developmental variability parallels (at least in some respects) inter‐individual variability in executive functions. Individuals who suffer damage or dysfunction in regions of the prefrontal cortex, for example, often experience difficulty in flexibly adapting their behavior to changes in context. As well, genetic differences between individuals are strongly associated with differences in executive control. Parallels between developmental and inter‐individual variability suggest hypotheses about possible mechanisms underlying the development of executive functions but carry risks when interpreted improperly. Overcoming these pitfalls will require mechanistic characterizations of executive functioning that are more deeply rooted in developmental principles. Copyright © 2010 John Wiley & Sons, Ltd.This article is categorized under:

Psychology > Brain Function and Dysfunction
Psychology > Development and Aging
Conditional weighted combination of wind power forecasts
Authors: Thordarson F. Ö. , Madsen H. , Nielsen H. Aa. , Pinson P. 
Published: May 2010

AbstractThe classical regression model for combined forecasting was reformulated in order to impose restrictions on the combination weights. This restricted linear combination model was then extended to the case where the weights were allowed to be a non‐parametric function of some meteorological variables, yielding the so‐called conditional weighted combination method. The weight functions are estimated with local regression techniques. The conditional weighted combination method was applied to a test case of a wind farm over a period of 10 months. Various combinations of two forecasts out of the three available ones were considered. Analysis of the data suggested that meteorological forecasts of air density and turbulent kinetic energy may be considered as relevant external variables in the combination scheme. A performance comparison showed that the conditional weighted combination method introduced in this paper outperformed the least‐squares combination method for almost all prediction horizons, especially for larger ones. This indicates that further developments based on conditional combination methods, including adaptivity of the weight functions estimation, may significantly enhance forecast accuracy and dampen the risk of large prediction errors. Copyright © 2010 John Wiley & Sons, Ltd.
Elemental mapping of frozen‐hydrated cells with cryo‐scanning X‐ray fluorescence microscopy
Authors: Matsuyama S. , Shimura M. , Fujii M. , Maeshima K. , Yumoto H. , Mimura H. , Sano Y. , Yabashi M. , Nishino Y. , Tamasaku K. , Ishizaka Y. , Ishikawa T. , Yamauchi K. 
Published: May 2010

AbstractVisualizing the elemental distributions of cells and tissues is of growing importance in biology and medical science because such data deepen our understanding of the behavior of metal‐binding proteins and ions. Elemental mapping by X‐ray fluorescence analysis with a hard X‐ray nanobeam is very well suited for this purpose owing to its high sensitivity and high resolution. Using this technique, samples must be prepared without artifacts that are caused by treatments such as chemical fixation and staining procedures. In many studies of elemental mapping, sample preparation is not explicitly considered. To overcome this deficiency, we developed a cryo‐scanning X‐ray fluorescence microscope and installed it in the second experimental hutch of BL29XUL of SPring‐8. We used it to observe frozen‐hydrated cells that had been fixed by a quick‐freezing technique to preserve elemental data of the living state at an X‐ray energy of 11.5 keV. The distributions of K, Ca, Fe, Cu and Zn were successfully visualized. The distributions of these elements (especially those of K, Ca and Fe) differed from those in cells fixed with paraformaldehyde. Copyright © 2010 John Wiley & Sons, Ltd.
Protein aggregation induced during glass bead lysis of yeast
Authors: Papanayotou Irene , Sun Beimeng , Roth Amy F. , Davis Nicholas G. 
Published: May 2010

AbstractYeast cell lysates produced by mechanical glass bead disruption are widely used in a variety of applications, including for the analysis of native function, e.g. protein–protein interaction, enzyme assays and membrane fractionations. Below, we report a striking case of protein denaturation and aggregation that is induced by this lysis protocol. Most of this analysis focuses on the type 1 casein kinase Yck2, which normally tethers to the plasma membrane through C‐terminal palmitoylation. Surprisingly, when cells are subjected to glass bead disruption, non‐palmitoylated, cytosolic forms of the kinase denature and aggregate, while membrane‐associated forms, whether attached through their native palmitoyl tethers or through a variety of artificial membrane‐tethering sequences, are wholly protected from denaturation and aggregation. A wider look at the yeast proteome finds that, while the majority of proteins resist glass bead‐induced aggregation, a significant subset does, in fact, succumb to such denaturation. Thus, yeast researchers should be aware of this potential artifact when embarking on biochemical analyses that employ glass bead lysates to look at native protein function. Finally, we demonstrate an experimental utility for glass bead‐induced aggregation, using its fine discrimination of membrane‐associated from non‐associated Yck2 forms to discern fractional palmitoylation states of Yck2 mutants that are partially defective for palmitoylation. Copyright © 2010 John Wiley & Sons, Ltd.