bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic viscosity and activation volume in chromium substituted Pb–M hexaferrite
Authors: Faloh‐Gandarilla J. C. , Díaz Castañón S. , Leccabue F.
Published: June 2005

PbFe11CrO19 polycrystalline samples were prepared by the chemical coprecipitation method. X‐ray diffraction and Mössbauer spectroscopy confirm the formation of the M‐type hexagonal structure. Time dependence of the magnetization was recorded on the demagnetization curve of the hysteresis loop. It is well described by a simple logarithmic law but also non‐logarithmic behavior was detected. A two‐peak dependence of the viscosity coefficient S with the applied field was encountered. Considering reversible susceptibility measurements and a M(H) curve at constant dM/dt in the irreversible susceptibility determination, the calculated activation volume as a function of the applied field shows two well defined zones. The zones observed in the activation volumes are related to the two local maxima that the total susceptibility exhibits. It points to the fact that the viscosity study is sensible enough to characterize this system, encountering two apparent activation volumes. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Self‐Assembly and Crystallization Behavior of Mesoporous, Crystalline HfO2 Thin Films: A Model System for the Generation of Mesostructured Transition‐Metal Oxides
Authors: Brezesinski Torsten , Smarsly Bernd , Iimura Ken‐ichi , Grosso David , Boissière Cédric , Amenitsch Heinz , Antonietti Markus , Sanchez Clément
Published: June 2005

Mesoporous thin films of crystalline hafnium oxide were fabricated by evaporation‐induced self‐assembly in combination with sol–gel processing, followed by a suitable post heat‐treatment procedure to initiate the crystallization. A novel type of block‐copolymer template was used as structure‐directing agent, which generated a distorted cubic arrangement of spherical mesopores, the size of which could be quantified by suitable techniques, such as ellipsometry–porosimetry, small‐angle X‐ray scattering, and atomic force microscopy. Detailed insights into the nature of the crystallization process of mesostructured hafnium oxide were obtained by temperature‐dependent, in situ X‐ray scattering experiments. These investigations revealed that crystallization takes place, within the confinement of the mesostructure, as a solid–solid transition from a dehydrated, amorphous form of hafnium oxide. The study suggests that one main benefit of the novel template results from the ability of the polymer to stabilize the mesostructure of amorphous hafnium oxide up to 400–450 °C.
The MyProxy online credential repository
Authors: Basney Jim , Humphrey Marty , Welch Von
Published: June 2005

The MyProxy online credential repository has been used by the Grid computing community for over four years for managing security credentials in the Grid public key infrastructure. MyProxy improves usability by giving users access to their credentials over the network using password authentication, allowing users to delegate their credentials via Web browser interfaces to the Grid, and supporting credential renewal for long‐running jobs. MyProxy helps administrators secure users' private keys by providing an online service from which users retrieve short‐lived credentials without distributing long‐lived keys to potentially vulnerable end‐systems. This paper describes the MyProxy system and its use. Copyright © 2005 John Wiley & Sons, Ltd.
The case for using Bridge Certificate Authorities for Grid computing
Authors: Humphrey Marty , Basney Jim , Jokl Jim
Published: June 2005

As Grid deployments increase, the challenge remains to create a scalable, multi‐organizational authentication infrastructure. Public key infrastructures (PKIs) are widely used for authentication in Grids, due in large part to the success of the Globus toolkit, despite the challenges and difficulties both for PKI administrators and users. The Bridge Certificate Authority (CA) is a compromise between a strictly hierarchical PKI and a mesh PKI and achieves many of the benefits of the hierarchical PKI and mesh PKI but has been untested for use with Grid software. This paper reports on the use of a Bridge CA with two representative Grid software packages: the Globus Toolkit v2 and WSRF.NET. We find that both packages support Bridge CAs sufficiently today to be usable in Grid software architectures, although not without limitations. In this paper, and through these experiments, we build the case for using Bridge CAs for Grid computing. Copyright © 2005 John Wiley & Sons, Ltd.
The GridSite Web/Grid security system
Authors: McNab Andrew
Published: June 2005

This paper describes the architecture of the GridSite system, which adds support for several Grid security protocols to the Apache Web server platform. These include the Globus GSI authentication system, Grid Access Control Language (GACL) access policy files, and Distinguished Name (DN) List and Virtual Organization Membership Service (VOMS) group memberships. Particular emphasis is placed on how the architecture of GridSite has evolved during the past 3 years, how this has been influenced by operational experience with production systems, and how the project has led to new developments, such as GACL. Finally, a description is given of how GridSite has been made to interoperate with other deployed security systems, both as producers and consumers of GridSite's authorization information. Copyright © 2005 John Wiley & Sons, Ltd.
‘R‐What?’ Development of a role‐based access control policy‐writing tool for e‐Scientists
Authors: Brostoff Sacha , Sasse M. Angela , Chadwick David , Cunningham James , Mbanaso Uche , Otenko Sassa
Published: June 2005

A lightweight role‐based access control policy authoring tool was developed for e‐Scientists, a community for which access policies have to be implemented for an increasingly heterogeneous group of local and remote users. Two fundamental problems were identified: (1) lack of understanding of what the policy components are (i.e. how authorization policies are structured), and (2) lack of understanding of the underlying policy paradigm (i.e. what should go into the policy, and what should be left out). Conceptual design (CD) techniques were used to revise the user interface (UI) labels so that e‐Scientists and developers were better able to describe access policy components from labels, and match labels with components (t = 6.28, df = 7, p = 0.000 two‐tailed). CD, instructional text, bubble help, UI behaviour and alert boxes were used to shape users' models of the policy paradigm. The final prototype improved users' efficiency and effectiveness by more than doubling the speed with which expert users could write authorization policies, and facilitating users without specialist security knowledge to overcome the policy paradigm and components problems, enabling them to complete 80% of basic and 75% of advanced authorization policy‐writing tasks in a usability trial. Copyright © 2005 John Wiley & Sons, Ltd.
Towards secure Grid‐enabled healthcare
Authors: Power D. J. , Politou E. A. , Slaymaker M. A. , Simpson A. C.
Published: June 2005

The primary focus of the UK e‐Science Programme is the development of software architectures, middleware and applications to support the end‐user scientific community in the undertaking of large‐scale research. A significant subset of e‐Science projects is concerned with the healthcare domain: as well as satisfying the needs of the end users, such projects have to consider the legal, ethical and security constraints associated with the use of sensitive patient data—these concerns are particularly relevant within the context of the U.K.'s National Health Service (NHS). In this paper we present a vision for Grid‐enabled healthcare that is sensitive to the information security requirements both of the NHS and the projects themselves. Although our motivation is principally derived from U.K.‐based e‐Health projects, this paper should be of interest to the worldwide health Grid community. By restricting ourselves to information security, we do not consider, for example, physical security or audit trail capabilities, which are outside the scope of this paper. The vision we describe is grounded in terms of experience, and reflects the challenges faced by the e‐DiaMoND project team. Copyright © 2005 John Wiley & Sons, Ltd.
Applying Security Design Analysis to a service‐based system
Authors: Chivers Howard , Fletcher Martyn
Published: June 2005

Risk analysis is the only effective way of making value judgments about the need for security. Established analysis methods apply to whole operational systems, taking a necessarily holistic view of security, but this makes them difficult to integrate into the design process for service‐based applications, where design and implementation are independent of operational deployment. However, the most costly mistakes occur early in the development lifecycle, and effective security can be difficult to retrofit, motivating the need for early security analysis. This paper describes SeDAn (Security Design Analysis), a security risk analysis framework that is adapted for use in the design phase of service‐based systems, and its application to a significant Grid‐based project (Distributed Aircraft Maintenance Environment—DAME). The complete lifecycle of the risk analysis is described, and the effectiveness of the process in identifying design defects validates both the need for, and the effectiveness of, this type of analysis. Copyright © 2005 John Wiley & Sons, Ltd.
Staged adoption of software product families
Authors: Bosch Jan
Published: June 2005

Several approaches to implement the concepts of software product families exist, but there is a tendency towards a revolutionary adoption. A revolutionary adoption of software product families is, however, a high‐risk undertaking that may easily fail. Even if an iterative, evolutionary adoption is applied, there is a substantial risk that mismatches may develop in the organization due to a sub‐optimal adoption approach. Mismatches between the optimal approach and the one currently used by an organization may lead to several problems, such as a high degree of erosion, mismatches between product needs and shared components, organizational ‘noise’ and inefficient knowledge management. This article (1) presents the problems resulting from the aforementioned mismatch, (2) presents the relevant decision dimensions that define the space of alternatives, (3) discusses the advantages and disadvantages of each alternative and (4) presents a framework for selecting the best alternative for each decision dimension based on a three‐stage adoption model. Copyright © 2005 John Wiley & Sons, Ltd.
Micro‐PIXE in ecophysiology
Authors: Przybyłowicz W. J. , Mesjasz‐Przybyłowicz J. , Migula P. , Nakonieczny M. , Augustyniak M. , Tarnawska M. , Turnau K. , Ryszka P. , Orłowska E. , Zubek Sz. , Głowacka E.
Published: June 2005

Two selected examples of PIXE microanalysis in ecophysiology are presented. Studies of heavy metal distributions in mycorrhizal and non‐mycorrhizal roots of Plantago lanceolata showed different filtration mechanisms of Zn/Pb and Fe/Mn, both enabling plants to cope with metals present in the environment. Studies of the mechanism used by the beetle Chrysolina pardalina to eliminate excessive amounts of Ni revealed that Malpighian tubules are responsible for the elimination of this metal from the hemolymph. In both examples GeoPIXE software was used for true elemental mapping using the Dynamic Analysis method and analysis of spectra from selected micro‐areas. Specimen thickness and matrix composition were obtained from proton backscattering spectra. Copyright © 2005 John Wiley & Sons, Ltd.
High‐energy PIXE using very energetic protons: quantitative analysis and cross‐sections
Authors: Denker A. , Bohne W. , Campbell J. L. , Heide P. , Hopman T. , Maxwell J. A. , Opitz‐Coutureau J. , Rauschenberg J. , Röhrich J. , Strub E.
Published: June 2005

Latterly, PIXE using high‐energy protons has been applied effectively for the qualitative analysis of archaeological and art objects, providing information from deep inside the object. This is due to the high cross‐sections for the excitation of K‐lines of heavy elements together with the large penetration depth of high‐energy protons, resulting in analysable depth of up to several millimetres. After the extension of the GUPIX software package to proton energies of up to 100 MeV, quantitative analysis came within reach. Measurements on thin and thick metal targets, and also on alloy standards with known composition and various thickness, were performed. The concentrations obtained were compared with the certified values. The agreement was good for samples with a thickness of around 2 mm. However, for several centimetre thick samples, the heavy elements were overestimated when using the K‐lines of these elements for the data evaluation. To clarify this, K‐shell cross‐section measurements were carried out for various Z. The measurements and the results are presented and discussed. Copyright © 2005 John Wiley & Sons, Ltd.
A perspective on the tenth international conference on particle induced x‐ray emission and its applications
Authors: Grime Geoffrey W.
Published: June 2005

The tenth meeting in the series of triennial International Conferences on Particle Induced X‐ray Emission (PIXE) and its Applications marks a milestone for the field. Not only is there the significance of the tenth occurrence of the meeting, reflecting perhaps a symbolic coming of age of the technique, but a new policy on publishing the proceedings has been introduced. Extended abstracts of all conference submissions have been published as a CD‐ROM, while contributions deemed by a panel of experienced PIXE scientists to represent the current status of PIXE development and applications were selected for publication in this journal, and so to be presented to a wider scientific audience than would normally be the case. The aim of this short introduction is to present an overview of the background and current state of development of PIXE to enable the succeeding papers to be seen in perspective. Copyright © 2005 John Wiley & Sons, Ltd.
Improvement of reproducibility in grazing‐exit EPMA (GE‐EPMA)
Authors: Tetsuoka K. , Nagamura T. , Tsuji K.
Published: June 2005

In grazing exit electron probe microanalysis (GE‐EPMA), characteristic x‐rays emitted from only near surface regions of a specimen are detected at extremely low exit angles near 0°. Therefore, GE‐EPMA is useful for localized surface analysis. However, there is a practical problem with GE‐EPMA, namely, reproducibility of angle adjustment. Therefore, we developed a new instrument, a ‘laser beam and four‐separated photodetector system’, to adjust the sample inclination. It was found that the reproducibility of angle adjustment was improved by about one‐tenth by applying this system. Copyright © 2005 John Wiley & Sons, Ltd.
Self‐element secondary fluorescence enhancement in XRF analysis
Authors: Karydas A. G.
Published: June 2005

In XRF analysis, the need for improved quantification approaches for non‐homogeneous samples requires a better understanding of all the energy‐dispersive spectrum features, in particular, the K/L or L/M intensity ratios among the characteristic x‐rays of the same element. These ratios are affected by the secondary fluorescence contribution of the more energetic characteristic x‐rays (K‐ or L‐lines) to the corresponding one of lower energy (L‐ or M‐lines, respectively). Theoretical calculations of the secondary fluorescence contribution among the characteristic x‐ray lines of the same element (self‐element secondary fluorescence enhancement) are presented for pure element targets by means of the fundamental parameter approach. For representative cases, the calculations were also performed for different exciting monochromatic x‐ray beam energies and as a function of the target thickness. The calculations predict that for pure targets and monochromatic exciting radiation, the self‐element secondary fluorescence enhancement contributes to the primary fluorescence intensity in a non‐negligible amount, up to about 20–25%. An experimental approach is proposed for the estimation in thick pure targets of the relative increase of the Mα, β fluorescence intensity due to the L‐line self‐element secondary fluorescence enhancement. Copyright © 2005 John Wiley & Sons, Ltd.
L x‐ray transitions in F‐like to Na‐like xenon ions determined at a room temperature electron beam ion trap
Authors: Kentsch U. , Zschornack G. , Grossmann F. , Ovsyannikov V. P. , Ullmann F. , Fritzsche S.
Published: June 2005

Fluorine‐like to sodium‐like xenon ions were investigated by wavelength‐dispersive x‐ray spectrometry at the Dresden Electron Beam Ion Trap (EBIT) working at room temperature. In addition to the precise measurement of the L x‐ray transition energies following ionization, excitation and recombination processes in the highly charged xenon ions, the spectra were analyzed for different gas pressures in the trap. Multiconfiguration Dirac‐Fock calculations are introduced that were applied to the energies, transition probabilities and excitation cross‐sections. The production of neon‐like xenon ions was demonstrated even at very high gas pressures. Copyright © 2005 John Wiley & Sons, Ltd.
EXAFS and XANES study of arsenic in contaminated soil
Authors: Arčon Iztok , van Elteren Johannes T. , Glass Hylke J. , Kodre Alojz , Šlejkovec Zdenka
Published: June 2005

Historical mining, processing and refinement of arsenic in purpose built calciners in Cornwall, UK, have resulted in extremely high contamination of soils with arsenic in some localized areas. The x‐ray absorption spectroscopic methods XANES (x‐ray absorption near‐edge structure) and EXAFS (extended x‐ray absorption fine structure) were used to retrieve arsenic molecular information, i.e. oxidation state and local structure around As atoms, in the soil from a calciner's residue dump near Camborne (which contained 8.82 wt% arsenic) and identify the most abundant modes of As bonding. The results show that arsenic is predominantly in pentavalent form, tetrahedrally bound to oxygen atoms in the first coordination sphere. Fe and Al atoms are found in the next neighbour coordination shells around As. The As–Fe and As–Al distances and coordination numbers strongly suggest that arsenate in the soil is present in two forms, viz. as amorphous or poorly crystalline hydrous oxides of Fe (most likely FeAsO4) and adsorbed on aluminium (hydr)oxides or aluminosilicates such as clay. Copyright © 2005 John Wiley & Sons, Ltd.
A novel high‐resolution XRF spectrometer for elemental mapping based on a monolithic array of silicon drift detectors and on a polycapillary x‐ray lens
Authors: Longoni A. , Fiorini C. , Guazzoni C. , Buzzetti S. , Bellini M. , Strüder L. , Lechner P. , Bjeoumikhov A. , Kemmer J.
Published: June 2005

This paper describes a novel x‐ray fluorescence spectrometer designed for elemental mapping applications. The spectrometer is based on a ring‐shaped monolithic array of silicon drift detectors (SDDs) with a hole in the center. The coaxial x‐ray excitation beam, focused by a polycapillary x‐ray lens, reaches the sample after passing through the central hole. This geometry optimizes the useful solid angle for collecting the fluorescence from the sample, while the optics maximizes the photon density in the excitation spot. These features, together with the very high detection rate of SDDs, allow a high scanning rate in elemental mapping to be achieved. Moreover, the spectroscopic resolution of SDDs (cooled by thermoelectric Peltier elements) is comparable to that of the classical Si(Li) liquid nitrogen‐cooled detectors. Several examples of applications of the novel spectrometer in various fields, from archeometry to biology, are presented. This paper introduces also a new multi‐element detector based on SDDs whose structure has been specifically optimized for very high resolution and very fast elemental mapping. Copyright © 2005 John Wiley & Sons, Ltd.
Auroral pulsations and accompanying VLF emissions
Authors: Tagirov V. R. , Ismagilov V. S. , Titova E. E. , Arinin V. A. , Perlikov A. M. , Manninen J. , Turunen T. , Kaila K.
Published: June 2005

Abstract. Results of simultaneous TV observations of pulsating auroral patches and ELF-VLF-emissions in the morning sector carried out in Sodankylä (Finland) on February 15, 1991 are presented. Auroral pulsating activity was typical having pulsating patches with characteristic periods of about 7 s. Narrow-band hiss emissions and chorus elements at intervals of 0.3–0.4 s formed the main ELF-VLF activity in the frequency range 1.0–2.5 kHz at the same time. The analysis of auroral images with time resolution of 0.04 s allowed perfectly separate analysis of spatial and temporal variations in the auroral luminosity. Mutual correspondence between the behaviour of the luminous auroral patches and the appearance of ELF noise type hiss emissions and VLF chorus trains was found in two intervals chosen for analysis. While the hiss emissions were associated with the appearance of luminosity inside a limited area close to the zenith, the structured VLF emissions were accompanied by rapid motion of luminosity inside the area. The spatial dimension of the pulsating area was about 45–50 km and luminosity propagated inside it with velocity of about 10–12 kms. We discuss a new approach to explain the 5–15 s auroral pulsation based on the theory of flowing cyclotron maser and relaxation characteristics of ionosphere.Key words. Magnetospheric physics (auroral phenomena; magnetosphere-ionosphere interactions) · Space plasma physics (wave-particle interactions)
Possible geomagnetic activity effects on weather
Authors: Bochníček J. , Hejda P. , Bucha V. , Pýcha J.
Published: June 2005

Abstract. Tropospheric temperature and pressure fields on the Northern Hemisphere in the winter periods 1952-1996 were investigated. Composite maps of those fields, created for the high and low geomagnetic activity and individual quasi-biennial oscillation (QBO), phases show clear differences not only between different levels of geomagnetic activity, but also between the two phases of QBO. Special attention was given to the behaviour of the lower troposphere in January and February 1982.Key words. Geomagnetism and paleomagnetism (time variations · diurnal to regular). Meteorology and atmospheric dynamics (general circulation; middle atmosphere dynamics)
The Earth's passage of the April 11, 1997 coronal ejecta: geomagnetic field fluctuations at high and low latitude during northward interplanetary magnetic field conditions
Authors: Lepidi S. , Francia P. , Villante U. , Meloni A. , Lazarus A. J. , Lepping R. P.
Published: June 2005

Abstract. An analysis of the low frequency geomagnetic field fluctuations at an Antarctic (Terra Nova Bay) and a low latitude (L'Aquila, Italy) station during the Earth's passage of a coronal ejecta on April 11, 1997 shows that major solar wind pressure variations were followed at both stations by a high fluctuation level. During northward interplanetary magnetic field conditions and when Terra Nova Bay is close to the local geomagnetic noon, coherent fluctuations, at the same frequency (3.6 mHz) and with polarization characteristics indicating an antisunward propagation, were observed simultaneously at the two stations. An analysis of simultaneous measurements from geosynchronous satellites shows evidence for pulsations at approximately the same frequencies also in the magnetospheric field. The observed waves might then be interpreted as oscillation modes, triggered by an external stimulation, extending to a major portion of the Earth's magnetosphere. Key words. Magnetospheric physics (MHD waves and instabilities; solar wind-magnetosphere interactions)
The 16-day planetary wave in the mesosphere and lower thermosphere
Authors: Mitchell N. J. , Middleton H. R. , Beard A. G. , Williams P. J. S. , Muller H. G.
Published: June 2005

Abstract. A meteor radar located at Sheffield in the UK has been used to measure wind oscillations with periods in the range 10–28 days in the mesosphere/lower-thermosphere region at 53.5°N, 3.9°W from January 1990 to August 1994. The data reveal a motion field in which wave activity occurs over a range of frequencies and in episodes generally lasting for less than two months. A seasonal cycle is apparent in which the largest observed amplitudes are as high as 14 ms–1 and are observed from January to mid-April. A minimum in activity occurs in late June to early July. A second, smaller, maximum follows in late summer/autumn where amplitudes reach up to 7–10 ms–1. Considerable interannual variability is apparent but wave activity is observed in the summers of all the years examined, albeit at very small amplitudes near mid summer. This behaviour suggests that the equatorial winds in the mesopause region do not completely prevent inter-hemispheric ducting of the wave from the winter hemisphere, or that it is generated in situ.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; thermospheric dynamics; waves and tides)
Stability results for obstacle problems with measure data
Authors: Leone Chiara
Published: June 2005

We study the convergence properties of the solutions of some elliptic obstacle problems with measure data, under the simultaneous perturbation of the operator, the forcing term and the obstacle.

On étudie les propriétés de convergence des solutions de problémes d'obstacles elliptiques avec données mesures, lorsque l'opérateur differentiel, les données ou les obstacles changent.
Ceramide‐1‐phosphate promotes cell survival through activation of the phosphatidylinositol 3‐kinase/protein kinase B pathway
Authors: Gómez-Muñoz Antonio , Kong Jennifer Y. , Parhar Kuljit , Wang Shih Wei , Gangoiti Patricia , González Mónica , Eivemark Sharlene , Salh Bill , Duronio Vincent , Steinbrecher Urs P.
Published: June 2005

In this report, we show for the first time that ceramide‐1‐phosphate (C1P) stimulates the phosphatidylinositol 3‐kinase (PI3‐K)/protein kinase B (PKB) pathway, which is a major mechanism whereby growth factors promote cell survival. Also, C1P induced IκB phosphorylation, and enhanced the DNA binding activity of the transcription factor NF‐κB. Apoptotic macrophages showed a marked reduction of Bcl‐XL levels, and this was prevented by C1P. These findings suggest that C1P blocks apoptosis, at least in part, by stimulating the PI3‐K/PKB/ NF‐κB pathway and maintaining the production of antiapoptotic Bcl‐XL. Based on these and our previous observations, we propose a working model for C1P in which inhibition of acid sphingomyelinase and the subsequent decrease in ceramide levels would allow cell signaling through stimulation of the PI3‐K/PKB pathway to promote cell survival.
Transmembrane homodimerization of receptor‐like protein tyrosine phosphatases
Authors: Chin Chen-Ni , Sachs Jonathan N. , Engelman Donald M.
Published: June 2005

Receptor‐like protein tyrosine phosphatases (RPTPs) are type I integral membrane proteins. Together with protein tyrosine kinases, RPTPs regulate the phosphotyrosine levels in the cell. Studies of two RPTPs, CD45 and PTPα, have provided strong evidence that dimerization leads to inactivation of the receptors, and that the dimerization of PTPα involves interactions in the transmembrane domain (TMD). Using the TOXCAT assay, a genetic approach for analyzing TM interactions in Escherichia coli membranes, we show that the TMD of RPTPs interact in the membrane, albeit to different extents. Using fusion proteins of TMDs, we also observe an equilibrium between monomer and dimer in sodium dodecyl sulfate (SDS) micelles. Through a mutational study of the DEP1 TMD, we demonstrate that these interactions are specific. Taken together, our results define a subset of the RPTP family in which TM homodimerization may act as a mediator of protein function.
STAT1 and Nmi are downstream targets of Ets‐1 transcription factor in MCF‐7 human breast cancer cell
Authors: Jung Hae Hyun , Lee Jeeyun , Kim Joo Hyun , Ryu Kyoung-Ju , Kang Sun-A , Park Chaehwa , Sung Kiwoong , Nam Do-Hyun , Kang Won Ki , Park Keunchil , Im Young-Hyuck
Published: June 2005

Ets‐1 is a cellular homologue of the product of the viral ets oncogene of the E26 virus, and it functions as a tissue‐specific transcription factor. It plays an important role in cell proliferation, differentiation, lymphoid cell development, transformation, angiogenesis, and apoptosis. Ets‐1 controls the expression of critical genes involved in these processes by binding to ets binding sites present in the transcriptional regulatory regions. Here, we transiently overexpressed Ets‐1 in MCF‐7 and comprehensively searched for potential downstream targets of Ets‐1 by cDNA microarray analysis. The expressions of several interferon‐related genes including STAT1 and Nmi were augmented by the overexpression of Ets‐1. RT‐PCR and Western blotting confirmed the increase in the levels of STAT1 and Nmi mRNA and protein. In contrast, Ets‐1 siRNA decreased the expression of STAT1 and Nmi proteins. As in our transient transfection experiments, stable overexpression of Ets‐1, also increased the protein expression of STAT1 and Nmi in MCF‐7 cells. Taken together, our results indicate that STAT1 and Nmi are downstream targets of Ets‐1 in MCF‐7 human breast cancer cells.
PACAP protects neuronal differentiated PC12 cells against the neurotoxicity induced by a mitochondrial complex I inhibitor, rotenone
Authors: Wang Gang , Qi Chen , Fan Guo-Hua , Zhou Hai-Yan , Chen Sheng-Di
Published: June 2005

In vivo and in vitro studies have suggested a neuroprotective role for Pituitary adenylate cyclase activating polypeptide (PACAP) against neuronal insults. Here, we showed that PACAP27 protects against neurotoxicity induced by rotenone, a mitochondrial complex I inhibitor that has been implicated in the pathogenesis of Parkinson's disease (PD). The neuroprotective effect of PACAP27 was dose‐dependent and blocked by its specific receptor antagonist, PACAP6‐27. The effects of PACAP27 on rotenone‐induced cell death were mimicked by dibutyryl‐cAMP (db‐cAMP), forskolin and prevented by the PKA inhibitor H89, the ERK inhibitor PD98059 and the p38 inhibitor SB203580. PACAP27 administration blocked rotenone‐induced increases in the level of caspase‐3‐like activity, whereas could not restore mitochondrial activity damaged by rotenone. Thus, our results demonstrate that PACAP27 has a neuroprotective role against rotenone‐induced neurotoxicity in neuronal differentiated PC12 cells and the neuroprotective effects of PACAP are associated with activation of MAP kinase pathways by PKA and with inhibition of caspase‐3 activity; the signaling mechanism appears to be mediated through mitochondrial‐independent pathways.
Treatment of Scaphoid Non-Union with a Percutaneous Corticocancellous Bone Graft
Authors: BULLENS P. H. J. , DRIESPRONG M. , LACROIX H. , VEGTER J.
Published: June 2005

Thirty-three symptomatic scaphoid non-unions were treated by a simple, minimally invasive procedure using a percutaneous autologous corticocancellous bone graft. After an average follow-up of 3.5 years, union was observed in 29 cases. These patients had no, or mild, pain at work and an almost normal range of motion and grip strength. No progression to osteoarthritis was observed.
Osteoarticular Allograft Reconstruction of the Distal Radius after Bone Tumour Resection
Authors: BIANCHI G. , DONATI D. , STAALS E. L. , MERCURI M.
Published: June 2005

Resection of the distal end of the radius is indicated in the treatment of locally aggressive primary benign and malignant bone tumours. The aim of this study was to evaluate the technique of osteoarticular allograft reconstruction of this bone defect. We analysed 12 patients retrospectively with a minimum follow-up of 2 years (range 26–145 months, median 52 months). Three patients had a malignant tumour and nine had a giant cell tumour. The patients ages ranged from 13 to 65 years. The mean resected length of the radius was 6.6 (range 4–14) cm. Non-union of the osteotomy line was diagnosed 6 months after surgery in one case and needed bone grafting. Distal radio–ulnar joint instability was observed in eight cases. Subchondral bone alterations and joint narrowing were present in all cases but were painful in only one patient. The mean range of motion was 51° of flexion and 37° of extension.
Hand Elevation Test for Assessment of Carpal Tunnel Syndrome
Authors: AMIRFEYZ R. , GOZZARD C. , LESLIE I. J.
Published: June 2005

The Hand Elevation test is a new provocative test for the diagnosis of carpal tunnel syndrome. We have investigated the sensitivity and specificity of this test in 48 patients with a clinical diagnosis of carpal tunnel syndrome and compared it to Tinel’s and Phalen’s tests. The Hand Elevation test was found to be 88% sensitive and 98% specific. This test is a simple, reproducible provocative test which is easily employed in conjunction with other known tests to assist in the diagnosis of carpal tunnel syndrome.
Absorptive capacity: Enhancing the assimilation of time‐based manufacturing practices
Authors: Tu Qiang , Vonderembse Mark A. , Ragu‐Nathan T.S. , Sharkey Thomas W.
Published: June 2005

Increasingly, manufacturers are making radical changes in management practices and investing heavily in advanced technologies as they attempt to achieve sustainable competitive advantage. Organizations seeking to implement these changes should have an internal environment that emphasizes knowledge assimilation and sharing and creates continuous learning capability, i.e., absorptive capacity. This study reviews the construct of absorptive capacity, develops a valid and reliable instrument to measure it, and examines its impact on the organization's ability to assimilate innovative manufacturing technology and management practice. To illustrate the links, this study tests the relationships among absorptive capacity, time‐based manufacturing practices, and value to customer. Structural equation modeling, applied to a relatively large sample (n= 303), indicates strong, positive, and direct relationships between absorptive capacity and time‐based manufacturing practices, and between time‐based manufacturing practices and value to customer. The managerial implications of these empirical findings are also discussed.
Postglacial vegetation, fire, and climate history of the Siskiyou Mountains, Oregon, USA
Authors: Briles Christy E. , Whitlock Cathy , Bartlein Patrick J.
Published: June 2005

The forests of the Siskiyou Mountains are among the most diverse in North America, yet the long-term relationship among climate, diversity, and natural disturbance is not well known. Pollen, plant macrofossils, and high-resolution charcoal data from Bolan Lake, Oregon, were analyzed to reconstruct a 17,000-yr-long environmental history of high-elevation forests in the region. In the late-glacial period, the presence of a subalpine parkland of Artemisia, Poaceae, Pinus, and Tsuga with infrequent fires suggests cool dry conditions. After 14,500 cal yr B.P., a closed forest of Abies, Pseudotsuga, Tsuga, and Alnus rubra with more frequent fires developed which indicates more mesic conditions than before. An open woodland of Pinus, Quercus, and Cupressaceae, with higher fire activity than before, characterized the early Holocene and implies warmer and drier conditions than at present. In the late Holocene, Abies and Picea were more prevalent in the forest, suggesting a return to cool wet conditions, although fire-episode frequency remained relatively high. The modern forest of Abies and Pseudotsuga and the present-day fire regime developed ca. 2100 cal yr B.P. and indicates that conditions had become slightly drier than before. Sub-millennial-scale fluctuations in vegetation and fire activity suggest climatic variations during the Younger Dryas interval and within the early Holocene period. The timing of vegetation changes in the Bolan Lake record is similar to that of other sites in the Pacific Northwest and Klamath region, and indicates that local vegetation communities were responding to regional-scale climate changes. The record implies that climate-driven millennial- to centennial-scale vegetation and fire change should be considered when explaining the high floristic diversity observed at present in the Siskiyou Mountains.
Interval mapping methods for detecting QTL affecting survival and time-to-event phenotypes
Authors: MORENO C. R. , ELSEN J. M. , LE ROY P. , DUCROCQ V.
Published: June 2005

Quantitative trait loci (QTL) are usually searched for using classical interval mapping methods which assume that the trait of interest follows a normal distribution. However, these methods cannot take into account features of most survival data such as a non-normal distribution and the presence of censored data. We propose two new QTL detection approaches which allow the consideration of censored data. One interval mapping method uses a Weibull model (W), which is popular in parametrical modelling of survival traits, and the other uses a Cox model (C), which avoids making any assumption on the trait distribution. Data were simulated following the structure of a published experiment. Using simulated data, we compare W, C and a classical interval mapping method using a Gaussian model on uncensored data (G) or on all data (G′=censored data analysed as though records were uncensored). An adequate mathematical transformation was used for all parametric methods (G, G′ and W). When data were not censored, the four methods gave similar results. However, when some data were censored, the power of QTL detection and accuracy of QTL location and of estimation of QTL effects for G decreased considerably with censoring, particularly when censoring was at a fixed date. This decrease with censoring was observed also with G′, but it was less severe. Censoring had a negligible effect on results obtained with the W and C methods.
Is the cost of herbicide resistance expressed in the breakdown of the relationships between characters? A case study using synthetic-auxin-resistant Arabidopsis thaliana mutants
Authors: ROUX FABRICE , REBOUD XAVIER
Published: June 2005

A mutation endowing herbicide resistance is often found to induce a parallel morphological or fitness penalty. To test whether such ‘cost’ of resistance to herbicides is expressed through lower resource acquisition, changes in resource allocation, or both, is of ecological significance. Here, we analysed 12 morphological traits in 900 plants covering three herbicide resistance mutations at genes AUX1, AXR1 and AXR2 in the model species Arabidopsis thaliana. Comparing these 2,4-D herbicide-resistant homozygous (RR) and heterozygous (RS) plants to homozygous susceptible (SS) plants, this analysis estimates the dominance level of the resistance allele on morphology. We also demonstrated that the herbicide resistance cost was primarily expressed as a change in resource acquisition (62·1–94% of the analysed traits). Although AUX1, AXR1 and AXR2 genes act in the same metabolic pathway of auxin response, each resistance factor was found to have its own unique signature in the way the cost was expressed. Furthermore, no link was observed between the absolute fitness penalty and the respective modifications of resource acquisition and/or resource allocation in the resistant plants. These results and their implications for herbicide resistance spread and establishment are discussed.
Further mapping of quantitative trait loci for postnatal growth in an intersubspecific backcross of wild Mus musculus castaneus and C57BL/6J mice
Authors: ISHIKAWA AKIRA , HATADA SAYURI , NAGAMINE YOSHITAKA , NAMIKAWA TAKAO
Published: June 2005

We performed a quantitative trait locus (QTL) analysis of eight body weights recorded weekly from 3 weeks to 10 weeks after birth and two weight gains recorded between 3 weeks and 6 weeks, and between 6 weeks and 10 weeks in an intersubspecific backcross population of wild Mus musculus castaneus mice captured in the Philippines and the common inbred strain C57BL/6J (M. musculus domesticus), to elucidate the complex genetic architecture of body weight and growth. Interval mapping identified 17 significant QTLs with main effects on 11 chromosomes. In particular, the main effect of the most potent QTL on proximal chromosome 2 increased linearly with age, whereas other QTLs exerted effects on either the early or late growth period. Surprisingly, although wild mice displayed 60% of the body size of their C57BL/6J counterparts, the wild-derived allele enhanced growth at two QTLs. Interestingly, five of the 17 main-effect QTLs identified had significant epistatic interaction effects. Five new epistatic QTLs with no main effects were identified on different chromosomes or regions. For one pair of epistatic QTLs, mice that were heterozygous for the wild-derived allele at one QTL and homozygous for that allele at another QTL exhibited the most rapid growth in all four possible genotypic combinations. Out of the identified QTLs, several showed significant sex-specific effects.
Map-based isolation of disease resistance genes from bread wheat: cloning in a supersize genome
Authors: KELLER BEAT , FEUILLET CATHERINE , YAHIAOUI NABILA
Published: June 2005

The genome of bread wheat is hexaploid and contains 1·6×1010 bp of DNA, of which more than 80% is repetitive sequences. Its size and complexity represent a challenge for the isolation of agronomically important genes, for which we frequently know only their position on the genetic map. Recently, new genomic resources and databases from genome projects have simplified the molecular analysis of the wheat genome. The first genes to be isolated from wheat by map-based cloning include three resistance genes against the fungal diseases powdery mildew and leaf rust. In this review, we will describe the approaches and resources that have contributed to this progress, and discuss genomic strategies that will simplify positional cloning in wheat in the near future.
Using markers to reduce the variation in the genomic composition in marker-assisted backcrossing
Authors: SERVIN BERTRAND
Published: June 2005

Marker-assisted introgression or backcrossing is a widely used method to improve commercial breeding lines or study the effects of genes in a homogeneous genetic background. In this context, the recovery of the recipient parent genome is a major objective of backcrossing. Selection on markers has been shown to be very useful to accelerate the rate of recovery of the recipient parent genome in backcrossing. In this study we show how much information markers give on the true genetic composition of individuals by deriving the variance and estimating the distribution of the genetic composition of individuals sharing a known genotype at markers. These calculations enable predictions of the number of individuals carrying an ideal genotype at markers that must be produced to fulfil background selection objectives.
Strong biases in the transmission of sex chromosomes in the aphid Rhopalosiphum padi
Authors: FRANTZ ADRIEN , PLANTEGENEST MANUEL , BONHOMME JOËL , PRUNIER-LETERME NATHALIE , SIMON JEAN-CHRISTOPHE
Published: June 2005

The typical life cycle of aphids involves several parthenogenetic generations followed by a single sexual one in autumn, i.e. cyclical parthenogenesis. Sexual females are genetically identical to their parthenogenetic mothers and carry two sex chromosomes (XX). Male production involves the elimination of one sex chromosome (to produce X0) that could give rise to genetic conflicts between X-chromosomes. In addition, deleterious recessive mutations could accumulate on sex chromosomes during the parthenogenetic phase and affect males differentially depending on the X-chromosome they inherit. Genetic conflicts and deleterious mutations thus may induce transmission bias that could be exaggerated in males. Here, the transmission of X-chromosomes has been studied in the laboratory in two cyclically parthenogenetic lineages of the bird cherry-oat aphid Rhopalosiphum padi. X-chromosome transmission was followed, using X-linked microsatellite loci, at male production in the two lineages and in their hybrids deriving from reciprocal crosses. Genetic analyses revealed non-Mendelian inheritance of X-chromosomes in both parental and hybrid lineages at different steps of male function. Putative mechanisms and evolutionary consequences of non-Mendelian transmission of X-chromosomes to males are discussed.
Bayesian and maximum likelihood estimation of genetic maps
Authors: YORK THOMAS L. , DURRETT RICHARD T. , TANKSLEY STEVEN , NIELSEN RASMUS
Published: June 2005

There has recently been increased interest in the use of Markov Chain Monte Carlo (MCMC)-based Bayesian methods for estimating genetic maps. The advantage of these methods is that they can deal accurately with missing data and genotyping errors. Here we present an extension of the previous methods that makes the Bayesian method applicable to large data sets. We present an extensive simulation study examining the statistical properties of the method and comparing it with the likelihood method implemented in Mapmaker. We show that the Maximum A Posteriori (MAP) estimator of the genetic distances, corresponding to the maximum likelihood estimator, performs better than estimators based on the posterior expectation. We also show that while the performance is similar between Mapmaker and the MCMC-based method in the absence of genotyping errors, the MCMC-based method has a distinct advantage in the presence of genotyping errors. A similar advantage of the Bayesian method was not observed for missing data. We also re-analyse a recently published set of data from the eggplant and show that the use of the MCMC-based method leads to smaller estimates of genetic distances.
Patterns of evolution of genes disrupted in expression in Drosophila species hybrids
Authors: NOOR MOHAMED A. F.
Published: June 2005

Divergence between species in regulatory pathways may contribute to hybrid incompatibilities such as sterility. Consistent with this idea, genes involved in male fertility often evolve faster than most other genes both in amino acid sequence and in expression. Previously, we identified a panel of male-specific genes underexpressed in sterile male hybrids of Drosophila simulans and D. mauritiana relative to pure species, and we showed that this underexpression is associated with infertility. In a preliminary effort to assess the generalities in the patterns of evolution of these genes, I examined patterns of mRNA expression in three of these genes in sterile F1 hybrid males of D. pseudoobscura and D. persimilis. F1 hybrid males bearing D. persimilis X chromosomes underexpressed all these genes relative to the parental species, while hybrids bearing D. pseudoobscura X chromosomes underexpressed two of these three genes. Interestingly, the third gene, CG5762, has undergone extensive amino acid evolution within the D. pseudoobscura species group, possibly driven by positive natural selection. We conclude that some of the same genes exhibit disruptions in expression within each of the two species groups, which could suggest commonalities in the regulatory architecture of sterility in these groups. Alternative explanations are also considered.
Beiträge der Sozialpsychologie zur Analyse und Lösung von Problemen im deutschen Gesundheitssystem
Authors: Koller Michael
Published: June 2005

Zusammenfassung: Ausgangspunkt dieser Darstellung ist die aktuelle Entwicklung in der Gesundheitsversorgung in Deutschland. Zur Debatte stehen tief greifende Änderungen im Versorgungssystem. Leitlinien, die medizinische Behandlungen nach dem neuesten Stand des Wissens festschreiben, werden als wichtiges Mittel zur Lösung vieler Probleme gesehen. Die Entwicklung von Leitlinien hat in den letzten Jahren große Fortschritte gemacht, und der Grund dafür, so das hier propagierte Argument, liegt in der Berücksichtigung von Prinzipien der Gruppenpsychologie. Ebenso wird aufgezeigt, warum die Akzeptanz und Implementierung von Leitlinien Schwierigkeiten bereitet, nämlich wegen der Vernachlässigung von motivationalen Faktoren. Die Sozialpsychologie hält einen wertvollen methodischen und konzeptuellen Schatz zur Analyse und Lösung im Gesundheitsbereich bereit. Die mangelnde Kenntnis dieses Umstandes ist nicht zuletzt einem schlechten Marketing der Sozialpsychologie zuzuschreiben.