bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural characterization of a new statherin from pig parotid granules
Authors: Manconi Barbara , Fanali Chiara , Cabras Tiziana , Inzitari Rosanna , Patamia Maria , Scarano Emanuele , Fiorita Antonella , Vitali Alberto , Castagnola Massimo , Messana Irene , Teresa Sanna Maria
Published: May 2010

This study describes the identification and structural characterization of Sus scrofa statherin. HPLC–electrospray ionization mass spectrometry analysis on pig parotid secretory granule extracts evidenced a peptide with a molecular mass value of 5381.1 ± 0.6 Da and its truncated form, devoid of the C‐terminal Ala residue, with a molecular mass value of 5310.1 ± 0.6 Da. The complete sequence of pig statherin gene was determined by sequencing the full‐length cDNA obtained by rapid amplification of cDNA ends. The gene is 549 base pairs long and contains an open reading frame of 185 nucleotides, encoding a 42‐amino acid secretory polypeptide with a signal peptide of 19 residues. This sequence presents some typical features of the four statherins characterized till now, showing the highest degree of amino acid identity with bovine (57%) and human statherin (39%). Pig statherin is mono‐phoshorylated on Ser‐3, while primate statherins already characterized are di‐phosphorylated on Ser‐2 and Ser‐3. This difference, probably connected to the Asp‐4 → Glu substitution, suggests the involvement of the Golgi‐casein kinase, which strictly recognizes the SX(E/pS) consensus sequence. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Double helix formation in α‐peptides: a theoretical study
Authors: Schramm Peter , Hofmann Hans‐Jörg
Published: May 2010

A complete overview on all possible hydrogen bonding patterns of double helices with antiparallel and parallel strand orientation in α‐peptide sequences is provided on the basis of ab initio molecular orbital theory. The most stable representatives belong to the group of antiparallel helices. The study on side chain influence shows that these double helices can only be realized if the strands are composed of L‐ and D‐amino acids in alternate order. The stability of the double helices is compared with that of competing single‐stranded helices. The data contribute to an understanding of secondary structure formation in peptides and provide a basis for a rational design of membrane channels. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
A study to assess the cross‐reactivity of cellulose membrane‐bound peptides with detection systems: an analysis at the amino acid level
Authors: Mahrenholz Carsten C. , Tapia Victor , Stigler Rolf D. , Volkmer Rudolf
Published: May 2010

The growing demand for binding assays to study protein–protein interaction can be addressed by peptide array‐based methods. The SPOT technique is a widespread peptide‐array technology, which is able to distinguish semi‐quantitatively the binding affinities of peptides to defined protein targets within one array. The quality of an assay system used for probing peptide arrays depends on the well‐balanced combination of screening and read‐out methods. The former address the steady‐state of analyte capture, whereas the latter provide the means to detect captured analyte. In all cases, however, false‐positive results can occur when challenging a peptide array with analyte or detecting captured analyte with label conjugates. Little is known about the cross‐reactivity of peptides with the detection agents. Here, we describe at the amino acid level the potential of (i) 5‐(and 6)‐carboxytetramethylrhodamine (5(6)‐TAMRA), (ii) fluoresceinisothiocyanate in form of the peptide‐bound fluorescein‐substituted thiourea derivative (FITC), and (iii) biotin/streptavidin‐POD to cross‐react with individual amino acids in a peptide sequence. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Tetrapeptides, as small‐sized peptidic inhibitors; synthesis and their inhibitory activity against BACE1
Authors: Kakizawa Taeko , Hidaka Koushi , Hamada Daisuke , Yamaguchi Ryoji , Uemura Tsuyoshi , Kitamura Hitomi , Tagad Harichandra D. , Hamada Takashi , Ziora Zyta , Hamada Yoshio , Kimura Tooru , Kiso Yoshiaki
Published: May 2010

β‐Site amyloid precursor protein cleaving enzyme 1 (BACE1) is known to be involved in the production of amyloid β‐peptide in Alzheimer's disease and is a major target for current drug design. We previously reported substrate‐based peptidomimetics, KMI‐compounds as potent BACE1 inhibitors. In this study, we designed and synthesized tetrapeptides as low molecular‐sized inhibitors. These exhibited high potency against recombinant BACE1, with the highest IC50 value of 34.6 nM from KMI‐927. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Influence of packaging design on littering and waste behaviour
Authors: Wever R. , van Onselen L. , Silvester S. , Boks C.
Published: May 2010

Littering is a packaging‐related problem where the environmental, social and economic aspects of sustainability meet. Litter is likely to be harmful for wildlife, looks untidy and is expensive to clean up. Research into reducing litter has focused primarily on the litterer and on the surroundings in which the littering occurs, but the influence of the littered object has so far been ill addressed. This research focused on understanding how the characteristics of an object influence its probability of being littered and how this insight can be used to improve the design of these objects, in particular packaging. Both eco‐feedback and scripting approaches were examined in four experimental setups. It was found that the design of a packaging does have a significant influence on waste behaviour of consumers. However, applying this insight to packaging design in order to reduce littering was found to be less than straightforward. Copyright © 2010 John Wiley & Sons, Ltd.
Altitudinal trends of leaf δ13C follow different patterns across a mountainous terrain in north China characterized by a temperate semi‐humid climate
Authors: Wang Guoan , Zhou Liping , Liu Min , Han Jiamao , Guo Jingheng , Faiia Anthony , Su Fang
Published: May 2010

Many studies have documented that the δ13C values of plants increase with altitude both on a global scale and locally in humid climates, while in semi‐arid areas the opposite trend has been found. The study reported herein was conducted in a mountainous area of China characterized by a temperate semi‐humid climate. The δ13C values of C3 species do not exhibit a consistent variation along an altitudinal gradient and the observations suggest that the pattern of increasing δ13C with altitude cannot be generalized. In the study area, in addition to environmental factors such as changing air pressure and light, the interaction between temperature and plant water balance determines the δ13C‐altitude variations in C3 plants. The δ13C of the leaves of C4 plants is found to increase with altitude with a mean gradient of 0.9‰/km. The altitudinal trend of C4 plants is attributed to the combined influences of water availability and other factors rather than temperature. Copyright © 2010 John Wiley & Sons, Ltd.
The distinguishing features of human metapneumovirus and respiratory syncytial virus
Authors: Papenburg Jesse , Boivin Guy
Published: May 2010

Acute respiratory tract infections (RTIs) are a leading cause of morbidity and mortality worldwide. Human Metapneumovirus (hMPV) is a member of the Metapneumovirus genus within the Pneumovirinae subfamily of the Paramyxoviridae family. Though hMPV was only discovered in 2001, a large body of work has already shown that it is the aetiologic agent of a substantial proportion of upper and lower RTIs across all age groups in both healthy and immunocompromised hosts throughout the world. RSV, also a pneumovirus, is the human pathogen most closely related to hMPV. RSV is the leading cause of pneumonia and bronchiolitis in infants and young children, but can also cause respiratory tract disease in all age groups. In this paper, we will review the salient features of the virology, epidemiology, pathogenesis, host immune responses, clinical manifestations and diagnostic modalities of hMPV, using RSV as a comparison. In addition, we will show how immunoprophylactic and therapeutic strategies studied and used in clinical practice for RSV—some with great success, and others tragic failure—have led to promising areas of research for the prevention and treatment of the significant burden of disease caused by hMPV. Copyright © 2010 John Wiley & Sons, Ltd.
Novel insights into proteolytic cleavage of influenza virus hemagglutinin
Authors: Bertram Stephanie , Glowacka Ilona , Steffen Imke , Kühl Annika , Pöhlmann Stefan
Published: May 2010

The influenza virus hemagglutinin (HA) mediates the first essential step in the viral life cycle, virus entry into target cells. Influenza virus HA is synthesised as a precursor protein in infected cells and requires cleavage by host cell proteases to transit into an active form. Cleavage is essential for influenza virus infectivity and the HA‐processing proteases are attractive targets for therapeutic intervention. It is well established that cleavage by ubiquitously expressed subtilisin‐like proteases is a hallmark of highly pathogenic avian influenza viruses (HPAIV). In contrast, the nature of the proteases responsible for cleavage of HA of human influenza viruses and low pathogenic avian influenza viruses (LPAIV) is not well understood. Recent studies suggest that cleavage of HA of human influenza viruses might be a cell‐associated event and might be facilitated by the type II transmembrane serine proteases (TTSPs) TMPRSS2, TMPRSS4 and human airway trypsin‐like protease (HAT). Here, we will introduce the different concepts established for proteolytic activation of influenza virus HA, with a particular focus on the role of TTSPs, and we will discuss their implications for viral tropism, pathogenicity and antiviral intervention. Copyright © 2010 John Wiley & Sons, Ltd.
Cumulative effects of restoration efforts on ecological characteristics of an open water area within the Upper Mississippi River
Authors: Gray B. R. , Shi W. , Houser J. N. , Rogala J. T. , Guan Z. , Cochran‐Biederman J. L.
Published: May 2010

Ecological restoration efforts in large rivers generally aim to ameliorate ecological effects associated with large‐scale modification of those rivers. This study examined whether the effects of restoration efforts—specifically those of island construction—within a largely open water restoration area of the Upper Mississippi River (UMR) might be seen at the spatial scale of that 3476 ha area. The cumulative effects of island construction, when observed over multiple years, were postulated to have made the restoration area increasingly similar to a positive reference area (a proximate area comprising contiguous backwater areas) and increasingly different from two negative reference areas. The negative reference areas represented the Mississippi River main channel in an area proximate to the restoration area and an open water area in a related Mississippi River reach that has seen relatively little restoration effort. Inferences on the effects of restoration were made by comparing constrained and unconstrained models of summer chlorophyll a (CHL), summer inorganic suspended solids (ISS) and counts of benthic mayfly larvae. Constrained models forced trends in means or in both means and sampling variances to become, over time, increasingly similar to those in the positive reference area and increasingly dissimilar to those in the negative reference areas. Trends were estimated over 12‐ (mayflies) or 14‐year sampling periods, and were evaluated using model information criteria. Based on these methods, restoration effects were observed for CHL and mayflies while evidence in favour of restoration effects on ISS was equivocal. These findings suggest that the cumulative effects of island building at relatively large spatial scales within large rivers may be estimated using data from large‐scale surveillance monitoring programs. Published in 2010 by John Wiley & Sons, Ltd.
Thermal regime suitability: Assessment of upstream range restoration potential for Colorado pikeminnow, a warmwater endangered fish
Authors: Osmundson D. B.
Published: May 2010

Dams have reduced distribution of the endangered Colorado pikeminnow Ptychocheilus lucius in the upper Colorado River basin: low‐head diversion dams blocked upstream passage and large dams inundated free‐flowing segments and cooled downstream reaches with deep‐water releases. To date, range restoration efforts in the Colorado and Gunnison Rivers have focused on building fish ladders around diversion dams to allow recolonization of upstream reaches. Upstream thermal suitability for this warmwater cyprinid was assessed using temperature data and existing distributional information from river reaches where Colorado pikeminnow movements were unrestricted. Among‐site thermal regime comparisons were made using mean annual thermal units (ATU), derived from mean daily temperatures during 1986–2005 and the relation between temperature and Colorado pikeminnow growth. Upstream distributional limits in the Yampa and Gunnison Rivers occurred where in‐channel thermal regimes fell below a long‐term mean of 47–50 ATU, suggesting that two Colorado River fish ladders will make available an estimated 17 km of thermally suitable habitat. A Gunnison River fish ladder successfully re‐established access to 54 km of suitable habitat, but 32 km of critical habitat upstream remains unsuitable. Suitability there could be achieved by raising temperatures only 1–2°C from late May to mid‐October with installation of a temperature control device on an upstream dam. Maximum, main‐channel, summer temperatures did not limit Colorado pikeminnow distribution in downstream reaches of the upper Colorado River. Published in 2010 by John Wiley & Sons, Ltd.
Development of a benthic macroinvertebrate flow sensitivity index for Canadian rivers
Authors: Armanini D. G. , Horrigan N. , Monk W. A. , Peters D. L. , Baird D. J.
Published: May 2010

Widespread alteration of flow regimes requires guidelines for the protection of river ecosystems based on sound science. Preservation of the biodiversity within river ecosystems and sustaining natural ecological functions are key aspects of their management. However, the relationship between the biota and flow‐related phenomena is poorly understood and, as a consequence, over‐simplistic hydrology‐based guidelines for river management have been adopted without establishing clear indicators of success. In the present paper, we aim to support the improvement of guidelines for flow (current velocity) management by developing a flow sensitivity index based on macroinvertebrates for Canadian rivers. Using benthic macroinvertebrate (BMI) samples collected by the Canadian Aquatic Biomonitoring Network (CABIN), current velocity preferences for the 55 most common invertebrate taxa across a range of reference and potential reference sites were derived. A Canadian Ecological Flow Index (CEFI) was developed based on these preferences. By testing the index against independent data, CEFI was found to respond mainly to changes in hydraulic conditions, and was minimally influenced by confounding factors (e.g. stream type, organic enrichment). The index was further validated using two independent data sets from the west and east of Canada, suggesting countrywide applicability of the method. In conclusion, we have developed a practical approach to evaluate relationships between hydrological regime and an important component of the river biota, permitting the development of an index which has good potential as an indicator for the effects of flow alteration. Moreover, we outline how the CEFI could be used as a tool for the development of holistic guidelines for the estimation of riverine flow needs. Copyright © 2010 Crown in the right of Canada and John Wiley & Sons, Ltd.
Satellite radio interfaces compatible to 3GPP WCDMA system
Authors: Kim Hee Wook , Lee Ho‐Jin , Martin Béatrice , Chuberre N. , Corazza G. E. , Vanelli‐Coralli A.
Published: May 2010

This paper provides an overview of a technical study on the satellite radio interfaces based on 3GPP WCDMA system. First, the outcome of the technical study is introduced, which has been carried out by the Mobile Satellite System Working Group of the ETSI Satellite Earth Satellite Technical Committee (ETSI TC SES MSS). The study dealt with the configurations and performance of the 3GPP WCDMA (UTRAN) radio interface over a satellite link. Second, as an evolution of satellite‐specific radio interface, the study results are addressed on the possible adaptations of WCDMA to the satellite link in order to maximize the radio link performance. The resultant outcome of the study was reflected in a detail on the G and C families of the satellite radio interface of the ITU‐R Recommendation M.1457, respectively. Copyright © 2010 John Wiley & Sons, Ltd.
A cooperative transmit diversity scheme for mobile satellite broadcasting systems
Authors: Ahn Do Seob , Kim Sooyoung , Kim Hee Wook , Park Dong‐Chul
Published: May 2010

In this study, we propose an efficient cooperative diversity scheme for mobile satellite multimedia broadcasting systems. The proposed scheme is a transmit diversity technique for adapting different channel environments, and thus, no channel quality information from the return link is needed. In the proposed scheme, we utilize space–time block codes and rate‐compatible turbo codes to achieve diversity gains and additional coding gains, respectively. The satellite and several repeaters on the ground cooperate to send the encoded signals, enabling the user terminal to realize diversity gain. The simulation results demonstrate that the proposed scheme can provide greatly improved performance. The simulation results in this study show that we can achieve about a 0.8 and 2.3 dB power gain by using the proposed cooperative diversity scheme without and with maximal ratio combining schemes, respectively, compared with the conventional scheme even, with a higher code rate. Copyright © 2010 John Wiley & Sons, Ltd.
Wetting of Cu substrates with micrometer and nanometer grains by molten Sn‐3.5Ag‐0.7Cu alloy
Authors: Shen Ping , Yin Zhongfa , Yang Jun , Sun Jianxin , Jiang Zhonghao , Jiang Qichuan
Published: May 2010

Wetting behaviors and interfacial microstructures of molten Sn‐3.5Ag‐0.7Cu drops on micrometer‐ and nanometer‐grained Cu substrates were studied. The wettability of the micrometer‐grained Cu substrates was found to be better than that of the nanometer‐grained substrates. Moreover, Kirkendall voids were observed at the interface of the nanometer‐grained Cu substrates but not of the micrometer‐grained substrates. It is presumed that the nanocrystalline surfaces are more prone to adsorption of impurities, thus reducing the surface free energy. On the other hand, its atomic diffusivity is greatly enhanced. As a result, the wettability deteriorates while the Kirkendall voids readily proliferate. Copyright © 2010 John Wiley & Sons, Ltd.
Surface characterization on graphitization of nanodiamond powder annealed in nitrogen ambient
Authors: Xie F. Y. , Xie W. G. , Gong L. , Zhang W. H. , Chen S. H. , Zhang Q. Z. , Chen J.
Published: May 2010

A nanodiamond thin film is deposited on a single crystal silicon substrate by dip‐coating technique. Surface characterization of the unannealed nanodiamond sample, and the samples annealed at various temperatures in nitrogen ambient, is conducted by XPS and Raman spectroscopy. The fitting data of the C1s core level XPS peak reveal that the sp2/sp3 ratio in the unannealed sample and the sample annealed at 900 °C and 1500 °C are 0.44, 0.55 and 6.08 respectively. All spectra including the C1s core level XPS spectrum, the plasmon energy‐loss spectrum associated with C1s peak, C KVV Auger spectrum of the sample annealed at 900 °C are similar to those of the unannealed sample. However, the spectra of the sample annealed at 1500 °C are very different. Annealing at 900 °C fails to produce appreciable graphitization, and an onion‐like carbon structure with a small diamond core is formed when the nanodiamond is heated to 1500 °C. Copyright © 2010 John Wiley & Sons, Ltd.
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

The 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

Complementary 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

In 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

An 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

In‐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

ToF‐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

Environmental 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

In 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

We 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

As 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

The 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

The 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

For 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

Flexibility 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

The 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

Visualizing 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

Yeast 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.
Les convictions politiques de Toland
Authors: Carrive Paulette
Published: May 2010

Si les sympathies de Toland pour le régime «républicain» (en anglais de l’époque, « commonwealthman » pour le substantif, « republican » pour l’adjectif ou le substantif) ne sont guère mises en doute aujourd’hui, encore faut-il s’entendre sur ce que signifie ce terme de «républicain». Les éditions que donna Toland d’ouvrages dont les thèses antiabsolutistes étaient connues de tous et les préfaces dont il les munit sont un argument sérieux en faveur d’un Toland « républicain ». Il faut cependant mettre en lumière les différents sens que Toland accepterait ou refuserait de donner à la notion de « république ». De nombreuses thèses de l’auteur sont communes aux whigs et aux républicains, et pourtant il manifeste sa méfiance à l’égard des partis. Ce qui est certain, c’est que Toland défend vivement les libertés – liberté de conscience, liberté de la presse, liberté du commerce – et aussi l’idée d’équilibre tant à l’intérieur des divers pouvoirs de l’État que dans le concert des nations.
John Toland: The Politics of Pantheism
Authors: Champion Justin A. I.
Published: May 2010

Cet article traite de la sincérité de la foi chrétienne publique de John Toland (1670-1722) et la confronte à ses croyances privées peu orthodoxes : le public et le privé dans la pensée de Toland sont séparés depuis trop longtemps. L'une des conséquences de cette reconstruction des idées religieuses de Toland sera de suggérer que ses opinions religieuses (publiques ou privées) étaient intimement liées à un programme politique. La plupart des études historiques le concernant se sont penchées principalement sur les aspects critiques de son attaque contre les intrigues sacerdotales du « papisme protestant » mais très peu de recherches ont été engagées sur l'idée de Toland comme « réformateur chrétien ». En explorant la définition précise que Toland donne du panthéisme et en la reliant à ses doctrines néostoïciennes sur la politique de la cité, le présent article propose une révision de la réflexion actuelle sur la signification de la vie publique de la foi chrétienne dans la polémique de la libre pensée.
L'infinitisme panthéiste de John Toland et ses relations avec la pensée de Giordano Bruno
Authors: Seidengart Jean
Published: May 2010

Il s’agit de repartir de la découverte et de l’acquisition, par John Toland, des principaux écrits de Giordano Bruno afin de déterminer l’impact de la philosophie nolaine sur la pensée du philosophe irlandais. Plus précisément, nous analyserons l’interprétation tolandienne de l’oeuvre de Bruno qui figure dans le mémoire qu’il adressa à ce sujet à son ami le baron Hohendorf. De là, nous dégagerons les grandes lignes de l’infinitisme panthéiste qui figurent dans les écrits ultérieurs de Toland pour tenter d’identifier, d’une part, ses emprunts au philosophe italien et, de l’autre, sa façon d’intégrer ou d’incorporer à sa propre pensée ces divers philosophèmes bruniens, en versant ainsi du vin nouveau dans de vieilles outres.
Sur les origines celtes de John Toland
Authors: Harrison Alan
Published: May 2010

Cet article établit que John Toland, né à la fin du xvne siècle, partageait la culture des Irlandais de langue maternelle gaélique. Il met en évidence l'intérêt de J. Toland, tout au long de sa vie, pour la culture et les langues celtes et repère l'influence de celles-ci sur le contenu et la présentation de ses idées peu orthodoxes.
Clidophorus et la question de la double philosophie
Authors: Lurbe Pierre
Published: May 2010

Dans Clidophorus, John Toland pose le problème de la relation entre philosophie ésotérique et philosophie exotérique : alors que la première nommée est la seule philosophie vraie, la seconde en est la traduction à l'usage du grand nombre. Il est en effet doublement nécessaire pour les philosophes de traduire la philosophie ésotérique en langage exotérique : il s’agit, d’une part, de se protéger, dans la mesure où la véritable philosophie contient un enseignement matérialiste radicalement incompatible avec les préjugés du vulgaire et des religions établies; et il s’agit, d’autre part, de donner à deviner la vérité sous des voiles suffisamment transparents pour que s’éveille la curiosité de disciples potentiels. La difficulté de l’entreprise tient donc à ce que la philosophie exotérique doit simultanément, et contradictoirement, permettre aux intelligences les plus fines d’acquérir un pressentiment de la vérité, sans mettre pour autant en cause les superstitions communément reçues. À cette aune, Toland juge que les fables des Anciens, forme antique de la philosophie exotérique, échouent dans la mesure où elles ne font qu’encourager la superstition; il suggère par contre implicitement que les métaphores dont Spinoza fait usage dans le Traité théologico-politique fournissent le modèle d’une philosophie exotérique qui traduise sans la trahir la philosophie ésotérique.
L'art de lire Toland
Authors: Jaffro Laurent
Published: May 2010

La compréhension de l’œuvre de John Toland suppose qu’on étudie ses différentes stratégies d’exposition. Il faut distinguer entre une première tentative de propagande ouverte, puis le choix de l’art d’écrire au sens que lui donne Leo Strauss, enfin le repli des dernières années sur la communauté ésotérique. Cette étude souligne que Toland a réfléchi les modalités de la communication de sa philosophie et a tenté de répondre à une question importante : comment une hétérodoxie peut-elle s’exposer dans l’espace public?