bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobile Calibration Based on Laser Metrology and Approximation Networks
Authors: Muñoz-Rodriguez J. Apolinar
Published: August 2010

A mobile calibration technique for three-dimensional vision is presented. In this method, vision parameters are computed automatically by approximation networks built based on the position of a camera and image processing of a laser line. The networks also perform three-dimensional visualization. In the proposed system, the setup geometry can be modified online, whereby an online re-calibration is performed based on data provided by the network and the required modifications of extrinsic and intrinsic parameters are thus determined, overcoming any calibration limitations caused by the modification procedure. The mobile calibration also avoids procedures involving references, which are used in traditional online re-calibration methods. The proposed mobile calibration thus improves the accuracy and performance of the three-dimensional vision because online data of calibrated references are not passed on to the vision system. This work represents a contribution to the field of online re-calibration, as verified by a comparison with the results based on lighting methods, which are calibrated and re-calibrated via perspective projection. Processing time is also studied.
Multi-Walled Carbon Nanotube-Doped Tungsten Oxide Thin Films for Hydrogen Gas Sensing
Authors: Wongchoosuk Chatchawal , Wisitsoraat Anurat , Phokharatkul Ditsayut , Tuantranont Adisorn , Kerdcharoen Teerakiat
Published: August 2010

In this work we have fabricated hydrogen gas sensors based on undoped and 1 wt% multi-walled carbon nanotube (MWCNT)-doped tungsten oxide (WO3) thin films by means of the powder mixing and electron beam (E-beam) evaporation technique. Hydrogen sensing properties of the thin films have been investigated at different operating temperatures and gas concentrations ranging from 100 ppm to 50,000 ppm. The results indicate that the MWCNT-doped WO3 thin film exhibits high sensitivity and selectivity to hydrogen. Thus, MWCNT doping based on E-beam co-evaporation was shown to be an effective means of preparing hydrogen gas sensors with enhanced sensing and reduced operating temperatures. Creation of nanochannels and formation of p-n heterojunctions were proposed as the sensing mechanism underlying the enhanced hydrogen sensitivity of this hybridized gas sensor. To our best knowledge, this is the first report on a MWCNT-doped WO3 hydrogen sensor prepared by the E-beam method.
A Universal Intelligent System-on-Chip Based Sensor Interface
Authors: Mattoli Virgilio , Mondini Alessio , Mazzolai Barbara , Ferri Gabriele , Dario Paolo
Published: August 2010

The need for real-time/reliable/low-maintenance distributed monitoring systems, e.g., wireless sensor networks, has been becoming more and more evident in many applications in the environmental, agro-alimentary, medical, and industrial fields. The growing interest in technologies related to sensors is an important indicator of these new needs. The design and the realization of complex and/or distributed monitoring systems is often difficult due to the multitude of different electronic interfaces presented by the sensors available on the market. To address these issues the authors propose the concept of a Universal Intelligent Sensor Interface (UISI), a new low-cost system based on a single commercial chip able to convert a generic transducer into an intelligent sensor with multiple standardized interfaces. The device presented offers a flexible analog and/or digital front-end, able to interface different transducer typologies (such as conditioned, unconditioned, resistive, current output, capacitive and digital transducers). The device also provides enhanced processing and storage capabilities, as well as a configurable multi-standard output interface (including plug-and-play interface based on IEEE 1451.3). In this work the general concept of UISI and the design of reconfigurable hardware are presented, together with experimental test results validating the proposed device.
Spatiotemporal variation in the reproductive ecology of two parapatric subspecies ofOenothera cespitosa(Onagraceae)
Authors: Artz Derek R. , Villagra Cristian A. , Raguso Robert A.
Published: August 2010

•Premise of the study: Flowering plants that rely on pollinators for most of their reproduction may experience unpredictable and inconsistent availability of effective pollinators throughout their reproductive lifetime. We investigated the reproductive ecology of two subspecies of the tufted evening primrose,Oenothera cespitosa, which occupy geographically and edaphically distinct habitats in western North America:O. cespitosasubsp.navajoensisinhabits sandstone soils on open sites or rocky slopes in the Colorado Plateau andO. cespitosasubsp.cespitosagrows in clay soils on talus slopes and exposed rocky ridges in the western Great Plains and northern Rocky Mountains of the United States.

•Methods: Pollen augmentation and selfing experiments, floral visitor observations, and single‐visit effectiveness experiments were conducted over 4 years to examine the breeding system and spatiotemporal variation in pollinator behavior, assemblage, and abundance at different populations for each subspecies.

•Key results: Both subspecies ofO. cespitosawere self‐incompatible and pollen‐limited, suggesting that the relative abundance, effectiveness, and movement patterns of different insects as pollinators influenced the quality and quantity of seed production in these plants. Medium‐sized vespertine hawkmoths (Hyles lineata,Sphinx vashti) were effective pollinators when present, as were large matinal bees (Anthophora affabilis,A. dammersi,Xylocopa tabaniformis androleuca), whereas small oligolecticLasioglossumbees primarily functioned as pollen thieves in the evening and morning.

•Conclusions: These findings highlight the importance of variability of pollinator composition and abundance in the evolution of plant breeding systems and reproductive success at varying spatial and temporal scales.
Management dans le secteur médico-social : le grand méli-mélo
Authors: Jourdy Philippe
Published: August 2010

Résumé Les récents textes législatifs ont modifié tout à la fois le contexte institutionnel du secteur médico-social, la place de l’usager dans ce système et les qualifications exigées pour en assurer la direction. C’est donc tout un ensemble de dimensions qui s’articulent pour dessiner un nouveau panorama au sein duquel la fonction de direction va devoir être redéfinie.
Carnets de bord
Authors: Puyuelo Rémy
Published: August 2010

Résumé Témoignage du journal de bord d’un pédo-psychiatre, directeur d’un institut de rééducation, en 1986. Comment l’écriture peut-elle constituer un mode d’analyse de cette pratique de direction ? À travers des instantanés de la vie du directeur et de l’institution, comment reprend-il ces moments de vie pour leur donner du sens et les utiliser dans l’animation de la vie institutionnelle ?
Le métier de directeur, toujours en devenir
Authors: Miramon Jean-Marie
Published: August 2010

Résumé Pour faire et être directeur, il faut acquérir une technicité dans les domaines de la gestion, de la méthodologie du projet, de la veille institutionnelle. Conditions nécessaires mais non suffisantes pour être directeur. La posture managériale et la stratégie sont une autre condition à l’exercice. À cette posture, il y a lieu de réaliser « un travail avec soi » , un travail pour mieux connaître son propre rapport au pouvoir et les valeurs qui fondent son action.
Clinique et management, quelles articulations possibles?
Authors: Rozès Bernard
Published: August 2010

Résumé À l’heure où le discours économique prend le pas sur toute autre considération de l’être humain, rechercher le point de rencontre entre la clinique et le management devient une priorité qui requiert engagement et éthique partagés. Cette voie est susceptible de concilier au mieux la réalité des contextes sociaux et économiques, au service de celles et ceux qui ont des difficultés à construire leur parcours de vie. Mener une réflexion permanente sur la façon de mettre en scène le pouvoir et l’autorité, rechercher un positionnement éthique, concevoir le projet comme un processus fédérateur d’identité et de culture représentent autant d’éléments qui permettent de faire vivre une organisation porteuse de sens, capable d’articuler la dimension thérapeutique et citoyenne.
Lier management et clinique ? Des paradoxes aux perspectives
Authors: Bouquet Brigitte
Published: August 2010

Résumé Comment penser l’intervention sociale, en tension entre sa nécessaire modernisation et un risque de contrôle social accru? Comment vivre avec ces paradoxes qu’il faut maîtriser au mieux ? Peut-on les transformer en ouverture sur le devenir ? Telle est la réflexion menée. Après avoir montré les effets a-critiques et contre-productifs de la gestion, pointés par de très nombreux auteurs sociologues, philosophes et une majorité de travailleurs sociaux, les conditions d’un « management social» sont abordées; ensuite est analysée la clinique sociale dans sa posture et ses enjeux. Si la démarche clinique consiste bien en une attention particulière portée à la personne, renvoie au sujet, toute clinique qui se développe au sein d’un établissement ne peut le faire qu’en s’articulant avec la vie institutionnelle. Et pour la société, la question d’une clinique porteuse des projets démocratiques énoncés dans la constitution de la République est plus que jamais posée. Pour tenter de passer des paradoxes aux prospectives, plusieurs voies sont mentionnées afin de lier management et clinique dans le respect des finalités du travail social.
Management d'institution sociale, la nécessité de se situer idéologiquement...
Authors: Martinelli Bertrand
Published: August 2010

Résumé La direction d’un internat scolaire ayant aussi fonction d’accompagnement préprofessionnel à l’extérieur, dans le canton de Vaud en Suisse, est modifiée par l’impact des nouvelles lois sur le « contrat de prestation » qui introduit le rapport contractuel entre les parties. Ce nouveau rapport s’inscrit sur fond de rationalisation du travail social, avec pour conséquence un découplage entre concept et application, entre contrôle de l’activité et prise en compte effective des sujets. Complémentairement à sa fonction de contrôle, le management rejoint la clinique lorsqu’il se donne pour tâche de mettre en œuvre les conditions de la prise en compte des sujets au cours de leur accompagnement.
Penser la clinique à l'heure du management : problématiques et concepts
Authors: Grimaud Lin
Published: August 2010

Résumé Parmi les problématiques du travail social, on relève des difficultés structurelles pour penser la pratique, mais aussi un fonds de recherches disponible qui est celui de la psychothérapie institutionnelle. Dans le contexte actuel, des concepts sont à dégager afin de permettre la reconnaissance d’un outil au service des usagers, tant de la part des cliniciens que de celle des gestionnaires.
Osons un autre paradigme pour penser l'émotion
Authors: Nouvelle Didier
Published: August 2010

Résumé Tout professionnel de la relation d’aide est confronté à la complexité du processus émotionnel et il est souvent difficile de se frayer un chemin dans la compréhension des émotions. Pourtant, de cette compréhension dépendront, en partie, la qualité et la justesse de nos interventions, c’est dire l’importance de notre vision épistémologique. C’est une clinique de l’émotion qui est explorée ici, non pas issue du modèle individualiste, où l’émotion est plutôt considérée comme un état interne à l’individu, mais dans une perspective relationnelle. L’angle de vue est alors réalisé avec une visée phénoménologique et une posture gestaltiste. Elles ouvrent de nouvelles voies pour repenser les émotions, ajuster, enrichir, les pratiques.
Les travailleurs sociaux : des chercheurs entre communication et action
Authors: Guillot Nathalie , Amato Stéphane
Published: August 2010

Résumé Cet article amorce une réflexion en faveur d’un nouvel enseignement dans la formation des travailleurs sociaux, celui des sciences de l’information et de la communication. Il s’appuie sur la nécessité de disposer de théories de la communication pour un nouvel « agir accompagnant », tente de montrer en quoi elles sont nécessaires au regard des problèmes que peuvent poser l’interdisciplinarité, tant sur un plan individuel que collectif, et, enfin, expose brièvement le paradigme de la communication engageante, exemple théorique qui pourrait venir renouveler certaines pratiques professionnelles.
La négociation : les enseignements du jeu de l'ultimatum
Authors: Petit Emmanuel
Published: August 2010

Résumé L’objectif de cet article est de retracer les enseignements récents issus des nombreux résultats expérimentaux du jeu de l’ultimatum. L’ultimatum est un jeu économique qui décrit la phase ultime d’un processus de négociation dans laquelle l’un des acteurs fait une offre « à prendre ou à laisser » à son partenaire, le répondant. Nous montrons tout d’abord le rôle majeur, à côté de la rationalité, des aspects affectifs dans la détermination des comportements de rupture de la négociation (rejet de l’offre). Le rôle des émotions est en particulier associé à l’intention qui sous-tend la proposition de l’offreur et aux anticipations des répondants. Nous nous focalisons ensuite sur les déterminants individuels de la négociation. Nous montrons notamment l’importance des facteurs de personnalité et de l’âge des sujets dans l’issue d’une négociation.
The application of the acoustic emission technique to stone decay by sodium sulphate in laboratory tests
Authors: Grossi C. M. , Esbert R M. , Suárez del Río L. M.
Published: August 2010

Acoustic emission was monitored during salt crystallisation cycles in order to study the mechanisms of rock deterioration by sodium sulphate in laboratory tests. Some porous carbonate stones used in Spanish monuments (Cathedral of Oviedo, Murcia and Seo Vella of Lérida) were selected for this study.
The acoustic emission detected during the different stages of the cycles (immersion, drying and cooling) was interpreted to be the result of the salt behaviour inside the stone. The use of this technique has confirmed that this behaviour depends on salt characteristics (solubility, hydration state and polymorphism of anhydrous sodium sulphate) and stone porosity and pore network.
Métodos microscópicos para la cuantificación del contenido en fase vítrea de escorias siderúrgicas
Authors: Rodríguez-Rey A. , Suárez del Río L. M. , Calleja Escudero L. , Ruiz de Argandoña V. G.
Published: August 2010

Some microscopy methods that can be applied to the quantification of the percentage of vitreous particles of blast furnace slags are reviewed. Details of sample preparation are included and the experimental procedure is briefly described. The main advantages and inconveniences of each method are also considered. All of these methods are appropriate for the routine control of slags that can be used as a cement addition, since they are simple, fast and inexpensive methods.
Creep of MDF panels under constant load and cyclic environmental conditions. Influence of surface coating
Authors: Fernández-Golfín Seco J. I. , Díez Barra M. Rafael
Published: August 2010

Four different strategies of surface coating (based on 80 g m2 melamin impregnated papers) were used on 19 mm thick commercial MDF panels to assess its reological behaviour under cyclic humidity conditions (20ºC 30 % rh-20ºC 90 % rh).
Three different levels of stress (20 %, 30 % and 40 %), based on the ultimate load in bending, were used. Tests were conducted by means of the three points load system.
For the same stress level, the relative creep of MDF panels was higher than that in particle boards with similar characteristics.
This behaviour was just the opposite than the one exhibited by the panels when the comparison is made based on the same level of load (kg) Melamin coating seems to strongly influence the creep behaviour of the raw material, especially when surface and edge coating were combined.
Composite materials in building: Introduction
Authors: Miravete A.
Published: August 2010

Not available
Mix design of steel fiber reinforced concrete
Authors: Moreno E. , Fernández Cánovas M.
Published: August 2010

Mix design of steel fiber reinforced concrete (SFRC) is concerned with achieving a workability, homogeneity, durability and strength suitable for its use.
Variables defining any mix design of SFRC are commented below, as well as their influence on some properties of fresh and hardened SFRC.
A special attention is paid to concrete, since it's the main use of steel fibers in Spain now, followed by paving construction.
Composite materials from new textile technologies
Authors: Jiménez M. A. , Castejón L. , Miravete A.
Published: August 2010

The present paper describes in a general way the most important of the advanced textile technologies which are oriented to the manufacturing of organic matrix composite materials, the paper presents their applications and the possibilities of future development. The use of these advanced weaving techniques allows the production of near-net-shaped preforms, which results in important savings in processing costs; moreover, these textile processes offer the possibility of introducing out-of plane reinforcing fibres, so there is an important increment of the impact strength and the damage tolerance of the final material.
Determination of the efficacy of two water repellents applied to granite
Authors: Rivas T. , Silva B. , Prieto B.
Published: August 2010

We evaluated the efficacy of two water-repellents applied to three types of granitic rock widely used in building construction and restoration in Galicia (NW Spain). The depth of penetration of the water-repellents was determined by measuring capillary absorption by the treated rock. The efficacies of the water-repellent were evaluated in terms of two parameters characteristic of surface wet: water-rock contact angle and the time taken for absorption of microgroplets. The effects of the treatments on the rocks' surface color and permeability to water vapor were also determined. The results indicate that neither water-repellent effectively penetrates the rock surface, and both induce undesirably high reductions in vapor permeability. Notwithstanding, both agents effectively improved the rocks' resistance to surface wetting, without altering its surface color. Overall, determination of water-rock contact angle and the time taken for absorption of microdroplets, together with colorimetric characterization of the treated rock, constitutes an useful approach to evaluation of the effects of water-repellents on granitic rocks. Nonetheless, it should be borne in mind that the marked heterogeneity of this type of rock, and the associated mineralogy and dominant type of fissuration are sources of considerable variation in the measurement parameters.
Elaboration of α’L-C2S form of belite in phosphatic clinker. Study of hydraulic activity
Authors: Diouri A. , Boukhari A. , Aride J. , Puertas F. , Vázquez T.
Published: August 2010

Solid state synthesis associated to X-ray diffraction and free lime analysis have been carried out to determine proper conditions (chemical compositions, optimum time and temperature of burning) under which phosphatic belitic clinker is elaborated. Raw meals, at low lime saturation factor and added phosphate, can form a clinker with high contents of α’L-C2S modification. Microcalorimetric measurements show a relative high hydraulic activity of this belite form. The phosphatic clinker exhibits a closeness hydration behaviour to the ordinary portland clinker.
Solid State compatibilities in CaO-CaO∙Al2O3-CaF2 system
Authors: Blanco-Varela M. T. , Jiménez Molina S.
Published: August 2010

In open atmosphere the two phases containing fluorine, C11A7∙CaF2 and 3CA∙CaF2, laying in the CaO-CaO∙Al2O3-CaF2 were synthesized. The synthesis of the 3CA∙CaF2 at 1.100°C was possible without loss of F, when the stoichiometric mixture of CA and CaF2 was pressed into tablets and was applied vacuum, avoiding in such a way the presence of moisture. According to TGA studies, the vapour pressure of phases containing fluorine, at 1.100°C is very low and follows this sequence: CaF2 < 3CACaF2 < C11A7∙CaF2. At 1.000°C the system behaves as condensated.
Verification of some compatibilities in solid state in the system CaO-CaO∙Al2O3-CaF2 at 1000°C has been done.
Compatibility triangles found are the same described by Chaterjee, and different from the compatibilities given by Brisi and Rolando.
Dry and wet "deposition" studies of the degradation of cement mortars
Authors: Martínez-Ramírez S. , Thompson G. E.
Published: August 2010

The reaction of portland cement mortars with SO2 gaseous pollutant and artificial 'acid rain' solution has been examined using laboratory exposure chambers, with realistic presentation rates of pollutants. The mortar were previously carbonated to produce superficial carbonation. Two mortars with different w/c ratio and hence specific surface were prepared and exposed into the chambers.
For dry deposition of SO2 pollutant gas, the important roles of water and water plus oxidant in increasing chemical reaction are readily revealed. Further, accessible porosity also increases reaction through increased times of reaction of pollutant with the mortars. Interestingly, in the absence of deliberate surface wetting, the presence of oxidant, ozone, leads to a reduction in the already limited extent of reaction. Wet deposition studies using artificial 'acid rain' solution result in gypsum formation, which is more extensive for mortars of increased w/c ratios.
Fundamentals of vanadium dioxide thin films as possible components of intelligent windows
Authors: Wu Z. P. , Nashiyama I. , Naramoto H.
Published: August 2010

In this paper, the research on the vanadium dioxide thin film, which can be used as intelligent windows, is reviewed, including the basic properties of V2, energy band structure, model of electronic energy and the origin of metal-to-insulator transition (MIT). Finally, the problems existing in the research and the possibility of application for VO2, as an intelligent thermochromic window are briefly discussed.
Decay of granite monuments due to salt crystallization in a non-polluted urban environment
Authors: García-Talegón J. , Vicente M. A. , Molina E.
Published: August 2010

The effect of salt crystallization on granite (s.l) rocks used as building material in an urban environment with low atmospheric pollution was studied. The manners of salt crystallization and the subsequent deterioration caused were analyzed in unweathered granite and other fades which had undergone strong transformations in quarries before being used as stone materials, "alterites".
Immobilisation/solidification of hazardous toxic waste in cement matrices
Authors: Macías A. , Goñi S. , Guerrero A. , Fernández E.
Published: August 2010

Immobilization and solidification of polluting waste, introduced into the industrial sector more than 20 years ago, and throughout last 10 years is being the object of a growing interest for engineers and environment scientists, has become a remarkable standardized process for treatment and management of toxic and hazardous liquid wastes, with special to those containing toxic metals.
Experimental monitorization of the behaviour of immobilized waste by solidification and stabilisation in life time safe deposits is not possible, reason why it is essential to develop models predicting adequately the behaviour of structures that have to undergo a range of conditions simulating the environment where they are to be exposed.
Such models can be developed only if the basic physical and chemical properties of the system matrix/solidifying-waste are known.
In this work immobilization/solidification systems are analyzed stressing out the formulation systems based on Portland cement. Finally, some examples of the results obtained from the study of interaction of specific species of wastes and fixation systems are presented.
Bare face red-brown bricks manufactured with fly ash from the Narcea (Asturias) Coal Power Plan
Authors: Ayesta G. , García M. P. , Blanco F. , Ayala J.
Published: August 2010

Fly ash, from the Coal Power Plant of Narcea (Asturias), has been used to determine its possible use as a raw material in the bare face red-brown brick manufacture.
The correct mould of a ceramic material demands a paste with an adequate plasticity. So, the optimum compositions of humidity, lubricant (talc) and binder (white dextrin) have been investigated. The samples were made by compressing paste into a mould using varying values of pressure and boiling temperature once the cooling speed had been established. Finally, the cooked pieces were submitted to trials demanded by the Basic Construction Norm, to see if they met the required specifications concerning Water Absorption, Suction, Contraction, Resistance to Freezing, Efflorescence and Compressive Strength.
Manufacturing of mortars and concretes non-traditionals, by Portland cement, metakaoline and gypsum (15.05%)
Authors: Talero R. , Bollati M. R. , Hernández F.
Published: August 2010

In a thorough previous research (1), it appeared that creation, evolution and development of the values of compressive mechanical strength (CS) and flexural strength (FS), measured in specimens 1x1x6cm of mortar type ASTM C 452-68 (2), manufactured by ordinary Portland cement P-1 (14.11% C3A) or PY-6 (0.00% C3A), metakaolin and gypsum (CaSO4∙2H2O) -or ternary cements, CT-, were similar to the ones commonly developed in mortars and concretes of OPC. This paper sets up the experimental results obtained from non-traditional mortars and concretes prepared with such ternary cements -TC-, being the portland cement/metakaolin mass ratio, as follows: 80/20, 70/30 and 60/40. Finally, the behaviour of these cements against gypsum attack, has been also determined, using the following parameters: increase in length (ΔL%), compressive, CS, and flexural, FS, strengths, and ultrasound energy, UE.
Experimental results obtained from these non-traditional mortars and concretes, show an increase in length (ΔL), in CS and FS, and in UE values, when there is addition of metakaolin.
Internalization and Coreceptor Expression Are Critical for TLR2-Mediated Recognition of Lipoteichoic Acid in Human Peripheral Blood
Authors: Bunk Sebastian , Sigel Stefanie , Metzdorf Daniela , Sharif Omar , Triantafilou Kathy , Triantafilou Martha , Hartung Thomas , Knapp Sylvia , von Aulock Sonja
Published: August 2010

Lipoteichoic acid (LTA), a ubiquitous cell wall component of Gram-positive bacteria, represents a potent immunostimulatory molecule. Because LTA of a mutant Staphylococcus aureus strain lacking lipoproteins (Δlgt-LTA) has been described to be immunobiologically inactive despite a lack of ascertained structural differences to wild-type LTA (wt-LTA), we investigated the functional requirements for the recognition of Δlgt-LTA by human peripheral blood cells. In this study, we demonstrate that Δlgt-LTA–induced immune activation critically depends on the immobilization of LTA and the presence of human serum components, which, to a lesser degree, was also observed for wt-LTA. Under experimental conditions allowing LTA-mediated stimulation, we found no differences between the immunostimulatory capacity of Δlgt-LTA and wt-LTA in human blood cells, arguing for a limited contribution of possible lipoprotein contaminants to wt-LTA–mediated immune activation. In contrast to human blood cells, TLR2-transfected human embryonic kidney 293 cells could be activated only by wt-LTA, whereas activation of these cells by Δlgt-LTA required the additional expression of TLR6 and CD14, suggesting that activation of human embryonic kidney 293 cells expressing solely TLR2 is probably mediated by residual lipoproteins in wt-LTA. Notably, in human peripheral blood, LTA-specific IgG Abs are essential for Δlgt-LTA–mediated immune activation and appear to induce the phagocytic uptake of Δlgt-LTA via engagement of FcγRII. In this study, we have elucidated a novel mechanism of LTA-induced cytokine induction in human peripheral blood cells that involves uptake of LTA and subsequent intracellular recognition driven by TLR2, TLR6, and CD14.
In Aged Mice, Outgrowth of Intraocular Melanoma Depends on Proangiogenic M2-Type Macrophages
Authors: Ly Long V. , Baghat Aabed , Versluis Mieke , Jordanova Ekaterina S. , Luyten Gregorius P. M. , van Rooijen Nico , van Hall Thorbald , van der Velden Pieter A. , Jager Martine J.
Published: August 2010

Macrophages are part of the tumor microenvironment and have been associated with poor prognosis in uveal melanoma. We determined the presence of macrophages and their differentiation status in a murine intraocular melanoma model. Inoculation of B16F10 cells into the anterior chamber of the eye resulted in rapid tumor outgrowth. Strikingly, in aged mice, tumor progression depended on the presence of macrophages, as local depletion of these cells prevented tumor outgrowth, indicating that macrophages in old mice had a strong tumor-promoting role. Immunohistochemistry and gene expression analysis revealed that macrophages carried M2-type characteristics, as shown by CD163 and peroxisome proliferator-activated receptor γ expression, and that multiple angiogenic genes were heavily overrepresented in tumors of old mice. The M2-type macrophages were also shown to have immunosuppressive features. We conclude that tumor-associated macrophages are directly involved in tumor outgrowth of intraocular melanoma and that macrophages in aged mice have a predisposition for an M2-type profile.
Tyrosine Kinase 2 Controls IL-1β Production at the Translational Level
Authors: Radwan Marta , Stiefvater Rita , Grunert Tom , Sharif Omar , Miller Ingrid , Marchetti-Deschmann Martina , Allmaier Günter , Gemeiner Manfred , Knapp Sylvia , Kovarik Pavel , Müller Mathias , Strobl Birgit
Published: August 2010

IL-1β is an important proinflammatory cytokine with a major role in several inflammatory diseases. Expression of IL-1β is tightly regulated at the level of transcription, mRNA stability, and proteolytic processing. In this study, we report that IL-1β expression in response to LPS is also regulated at the translational level. LPS-induced IL-1β protein levels in macrophages derived from murine bone marrow are markedly increased in the absence of tyrosine kinase 2 (Tyk2). Increased IL-1β is found intra- and extracellularly, irrespective of the efficiency of IL-1β processing. We show that the absence of Tyk2 results both in higher translational rates and in enhanced association of IL-1β mRNA with polysomes. Induction and stability of IL-1β mRNA are not affected by the lack of Tyk2. We show further that the Tyk2-dependent translational inhibition is mediated by autocrine/paracrine type I IFN signaling and requires signal transducer and activator of transcription 1. Enhanced IL-1β production in Tyk2- and IFN receptor 1-deficient macrophages is also observed following Listeria monocytogenes infection. Taken together, the data describe a novel mechanism for the control of IL-1β synthesis.
TCR-Induced Activation of Ras Proceeds at the Plasma Membrane and Requires Palmitoylation of N-Ras
Authors: Rubio Ignacio , Grund Stefan , Song Shu-Ping , Biskup Christoph , Bandemer Sabine , Fricke Melanie , Förster Martin , Graziani Andrea , Wittig Ute , Kliche Stefanie
Published: August 2010

Ras transmits manifold signals from the TCR at various crossroads in the life of a T cell. For example, selection programs in the thymus or the acquisition of a state of hypo-responsiveness known as anergy are just some of the T cell features known to be controlled by TCR-sparked signals that are intracellularly propagated by Ras. These findings raise the question of how Ras can transmit such a variety of signals leading to the shaping of equally many T cell traits. Because Ras proteins transit through endomembrane compartments on their way to the plasma membrane (PM), compartmentalized Ras activation at distinct subcellular sites represents a potential mechanism for signal diversification in TCR signaling. This hypothesis has been nurtured by studies in T cells engineered to overexpress Ras that reported distinct activation of Ras at the PM and Golgi. Contrary to this scenario, we report in this study that activation of endogenous Ras, imaged in live Jurkat T cells using novel affinity probes for Ras-GTP, proceeds only at the PM even upon enforced signal flux through the diacylglycerol/RasGRP1 pathway. Physiological engagement of the TCR at the immunological synapse in primary T cells caused focalized Ras-GTP accumulation also only at the PM. Analysis of palmitoylation-deficient Ras mutants, which are confined to endomembranes, confirmed that the TCR does not activate Ras in that compartment and revealed a critical function for palmitoylation in N-Ras/H-Ras activation. These findings identify the PM as the only site of TCR-driven Ras activation and document that endomembranes are not a signaling platform for Ras in T cells.
T-bet and Eomesodermin Are Required for T Cell-Mediated Antitumor Immune Responses
Authors: Zhu Yibei , Ju Songguang , Chen Elizabeth , Dai Shao , Li Changyou , Morel Penelope , Liu Lin , Zhang Xueguang , Lu Binfeng
Published: August 2010

Cell-mediated adaptive immunity is very important in tumor immune surveillance and tumor vaccination. However, the genetic program underlying an effective adaptive antitumor immunity is elusive. T-bet and Eomesodermin (Eomes) have been suggested to be master regulators of Th1 cells and CD8+ T cells. However, whether they are important for T cell-mediated antitumor immunity is controversial. In this paper, we show that the combined germline deletion of T-bet and T cell-specific deletion of Eomes resulted in profound defects in adaptive antitumor immune responses. T-bet and Eomes drive Tc1 differentiation by preventing alternative CD8+ T cell differentiation to Tc17 or Tc2 cells. Surprisingly, T-bet and Eomes are not critical for the generation of systemic CTL activities against cancer cells. Instead, T-bet and Eomes are crucial for tumor infiltration by CD8+ T cells. This study defines T-bet and Eomes as critical regulators of T cell-mediated immune responses against tumor.
Nonsteroidal Anti-Inflammatory Drugs Increase TNF Production in Rheumatoid Synovial Membrane Cultures and Whole Blood
Authors: Page Theresa H. , Turner Jeremy J. O. , Brown Anthony C. , Timms Emma M. , Inglis Julia J. , Brennan Fionula M. , Foxwell Brian M. J. , Ray Keith P. , Feldmann Marc
Published: August 2010

Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit cyclooxygenase activity and hence PG production. However, the ability of NSAIDs to ameliorate pain and tenderness does not prevent disease progression in rheumatoid arthritis, a disease whose pathogenesis is linked to the presence of proinflammatory cytokines, such as TNF-α. To understand this observation, we have examined the effect of NSAIDs on the production of clinically validated proinflammatory cytokines. We show that a variety of NSAIDs superinduce production of TNF from human peripheral blood monocytes and rheumatoid synovial membrane cultures. A randomized, double-blinded, crossover, placebo-controlled trial in healthy human volunteers also revealed that the NSAID drug celecoxib increased LPS-induced TNF production in whole blood. NSAID-mediated increases in TNF are reversed by either the addition of exogenous PGE2 or by a PGE2 EP2 receptor agonist, revealing that PGE2 signaling via its EP2 receptor provides a valuable mechanism for controlling excess TNF production. Thus, by reducing the level of PGE2, NSAIDs can increase TNF production and may exacerbate the proinflammatory environment both within the rheumatoid arthritis joint and the systemic environment.
Restricted TCR-α CDR3 Diversity Disadvantages Natural Regulatory T Cell Development in the B6.2.16 β-Chain Transgenic Mouse
Authors: Singh Yogesh , Ferreira Cristina , Chan Andrew C. Y. , Dyson Julian , Garden Oliver A.
Published: August 2010

To date, analysis of mice expressing TCR-β transgenes derived from CD4+ T cell clones has demonstrated equivalent or higher TCR diversity in naturally occurring regulatory CD4+ T cells (Tregs) versus conventional CD4+ T cells (Tcons). However, TCR-α–chain diversity in these mice may be influenced by the inherent bias toward the CD4+ lineage in the selected repertoires. We wished to determine whether the choice of TCR-β–chain influences the relative diversity of the Treg and Tcon repertoires, examining as a model the B6.2.16β-transgenic mouse, in which the fixed β-chain is derived from a CD8+ T cell clone. B6.2.16β Treg thymocytes showed significantly lower TRAV17 (AV9) CDR3 sequence diversity than both syngeneic Tcon thymocytes, and Treg and Tcon thymocytes from wild-type C57BL/6 (B6) mice. The ratio of single-positive CD4+/single-positive CD8+ thymocytes in B6.2.16β mice was similar to that in B6, yet both the proportional frequency and absolute number of CD4+Foxp3+ cells was significantly lower in the thymi and peripheral lymph nodes of B6.2.16β mice. Furthermore, B6 + B6.2.16β→B6 mixed bone marrow chimeras revealed that the transgenic β-chain disadvantaged Treg development in a competitive environment. These data underline the importance of the β-chain in assessments of Treg α-chain diversity and provide further support for the notion that interclonal competition for entry into the Treg lineage is a significant factor in determining the composition of this lineage.
IL-10 Restricts Memory T Cell Inflation during Cytomegalovirus Infection
Authors: Jones Morgan , Ladell Kristin , Wynn Katherine K. , Stacey Maria A. , Quigley Máire F. , Gostick Emma , Price David A. , Humphreys Ian R.
Published: August 2010

The β-herpesvirus CMV induces a substantial and progressive expansion of virus-specific memory CD8 T cells, which protect the host against viral reactivation from latency. In this paper, we report that this expansion, or “inflation,” of memory T cells is amplified dramatically during mouse CMV infection of IL-10 knockout (IL-10−/−) mice. T cells from IL-10−/− mice were oligoclonal, exhibited a highly activated phenotype, expressed antiviral cytokines, and degranulated in response to cognate Ag encounter ex vivo. Moreover, latent viral load was reduced in IL-10−/− mice. Importantly, these results were recapitulated by IL-10R blockade during chronic/latent infection of wild-type mice. These data demonstrate that regulatory immune mechanisms can influence CMV-specific T cell memory and suggest a possible rationale for the acquisition of functional IL-10 orthologs by herpesviruses.
Directly Transfected Langerin+ Dermal Dendritic Cells Potentiate CD8+ T Cell Responses following Intradermal Plasmid DNA Immunization
Authors: Elnekave Mazal , Furmanov Karina , Nudel Itay , Arizon Moran , Clausen Björn E. , Hovav Avi-Hai
Published: August 2010

Dendritic cells (DCs) play a critical role in CD8+ T cell priming following DNA vaccination. In contrast to other DNA injection routes or immunization with viral vectors, Ag presentation is delayed following needle injection of plasmid DNA into the skin. The contribution of various skin DC subsets to this process is not known. In this study, we show that dermal CD11c+ cells are the most important transgene-expressing cells following immunization. Using langerin- diphtheria toxin receptor mice we demonstrated that langerin+ dermal DCs (Ln+dDCs) were crucial for generating an optimal CD8+ T cell response. Blocking migration of skin cells to the lymph node (LN) ablated immunogenicity, suggesting that migration of dDC subsets to the LN is essential for generating immunity. This migration generated a weak Ag-presenting activity in vivo until day 5 postimmunization, which then increased dramatically. We further found that Ln+dDCs and dDCs were the only DC populations directly presenting Ag to CD8+ T cells ex vivo during the initial 8-d period postimmunization. This activity changed on the following days, when both skin DCs and LN-resident DCs were able to present Ag to CD8+ T cells. Taken together, our in vivo and ex vivo results suggest that activation of CD8+ T cells following intradermal plasmid DNA immunization depends on directly transfected Ln+dDCs and dDCs. Moreover, the type of DCs presenting Ag changed over time, with Ln+dDCs playing the major role in potentiating the initial CD8+ T cell response.
Criteria for Very Ampleness of Rank Two Vector Bundles over
Ruled Surfaces
Authors: Alzati Alberto , Besana Gian Mario
Published: August 2010

Very ampleness criteria for rank 2 vector bundles over smooth, ruled
surfaces over rational and elliptic curves are given. The criteria are then
used to settle open existence questions for some special threefolds of low
degree.
Asymptotic Formulae for Pairs of Diagonal Cubic Equations
Authors: Brüdern Jörg , Wooley Trevor D.
Published: August 2010

We investigate the number of integral solutions possessed by a pair of diagonal cubic equations in a large box. Provided that the number of variables in the system is at least fourteen, and in addition the number of variables in any non-trivial linear combination of the underlying forms is at least eight, we obtain an asymptotic formula for the number of integral solutions consistent with the product of local densities associated with the system.
Externalizing problems and problematic sexual behaviors: same etiology?
Authors: Lévesque Mireille , Bigras Marc , Pauzé Robert
Published: August 2010

The study sought to determine whether maltreatment subtypes, family sexuality, and personal characteristics predicted and distinguished child problematic sexual behaviors (PSB) and externalizing problems (EP). Participants were families of 188 children, 6–11 years old, referred by child welfare services in four Quebec districts. Caregivers completed interviews and questionnaires. Results suggested that family environment and maltreatment subtypes had partially different impacts on PSB and EP. When EP and gender were controlled, younger children in a sexualized family environment and those verbally victimized were more likely to exhibit PSB. When PSB and gender were controlled, verbal abuse and neglect emerged as predictors of EP. Potential implications for child PSB research and interventions are discussed. Aggr. Behav. 36:358–370, 2010. © 2010 Wiley‐Liss, Inc.
Direct Observation of Capacitor Switching Using Planar Electrodes
Authors: Balke Nina , Gajek Martin , Tagantsev Alexander K. , Martin Lane W. , Chu Ying‐Hao , Ramesh Ramamoorthy , Kalinin Sergei V.
Published: August 2010

Ferroelectric polarization switching in epitaxial (110) BiFeO3 films is studied using piezoresponse force microscopy of a model in‐plane capacitor structure. The electrode orientation is chosen such that only two active domain variants exist. Studies of the kinetics of domain evolution allows clear visualization of nucleation sites, as well as forward and lateral growth stages of domain formation. It is found that the location of the reverse‐domain nucleation is correlated with the direction of switching in a way that the polarization in the domains nucleated at an electrode is always directed away from it. The role of interface charge injection and surface screening charge on switching mechanisms is explored, and the nucleation is shown to be controllable by the bias history of the sample. Finally, the manipulation of domain nucleation through domain structure engineering is illustrated. These studies pave the way for the engineering and design of the ferroelectric device structures through control of individual steps of the switching process.
High Breakdown Field Dielectric Elastomer Actuators Using Encapsulated Polyaniline as High Dielectric Constant Filler
Authors: Molberg Martin , Crespy Daniel , Rupper Patrick , Nüesch Frank , Månson Jan‐Anders E. , Löwe Christiane , Opris Dorina M.
Published: August 2010

A novel method allowing rapid production of reliable composites with increased dielectric constant and high dielectric strength for dielectric elastomer actuators (DEA) is reported. The promising approach using composites of conductive particles and insulating polymers generally suffers from low breakdown fields when applied to DEA devices. The present publication shows how to overcome this deficiency by using conductive polyaniline (PANI) particles encapsulated into an insulating polymer shell prior to dispersion. PANI particles are encapsulated using miniemulsion polymerization (MP) of divinylbenzene (DVB). The encapsulation process is scaled up to approximately 20 g particles per batch. The resulting particles are used as high dielectric constant (ϵ′) fillers. Composites in a polydimethylsiloxane (PDMS) matrix are prepared and the resulting films characterized by dielectric spectroscopy and tensile tests, and evaluated in electromechanical actuators. The composite films show a more than threefold increase in ϵ′, breakdown field strengths above 50 V μm−1, and increased strain at break. These novel materials allow tuning the actuation strain or stress output and have potential as materials for energy harvesting.
Formation of Nickel Oxide Nanotubes with Uniform Wall Thickness by Low‐Temperature Thermal Oxidation Through Understanding the Limiting Effect of Vacancy Diffusion and the Kirkendall Phenomenon
Authors: Ren Yi , Chim Wai Kin , Chiam Sing Yang , Huang Jin Quan , Pi Can , Pan Ji Sheng
Published: August 2010

In this work, the step‐wise oxidation mechanism of nickel (Ni) nanowires is elucidated. Rapid vacancy diffusion plays a significant role at low temperatures in forming heterostructures of nickel oxide (NiO) nanotubes with Ni nanowires. Subsequent investigations of Ni nanowire oxidation at higher temperatures and faster temperature ramp rates show that it is difficult to bypass this rapid vacancy diffusion stage, which affects the formation of the final structure. Therefore, it is unlikely to form solid NiO nanowires or NiO nanotubes with uniform wall thickness through the conventional annealing/oxidation process of Ni nanowires. Instead, a step‐wise oxidation process by combining low temperature oxidation with a chemical etching step is utilized to produce for the first time NiO nanotubes with uniform wall thickness from Ni nanowires.
Polymer–Fullerene Bulk‐Heterojunction Solar Cells
Authors: Brabec Christoph J. , Gowrisanker Srinivas , Halls Jonathan J. M. , Laird Darin , Jia Shijun , Williams Shawn P.
Published: August 2010

Solution‐processed bulk heterojunction organic photovoltaic (OPV) devices have gained serious attention during the last few years and are established as one of the leading next generation photovoltaic technologies for low cost power production. This article reviews the OPV development highlights of the last two decades, and summarizes the key milestones that have brought the technology to today’s efficiency performance of over 7%. An outlook is presented on what will be required to drive this young photovoltaic technology towards the next major milestone, a 10% power conversion efficiency, considered by many to represent the efficiency at which OPV can be adopted in wide‐spread applications. With first products already entering the market, sufficient lifetime for the intended application becomes more and more critical, and the status of OPV stability as well as the current understanding of degradation mechanisms will be reviewed in the second part of this article.
Carbon Nanotubes in the Biological Interphase: The Relevance of Noncovalence
Authors: Lee Yeonju , Geckeler Kurt E.
Published: August 2010

With the increasing interest in the biological applications of carbon nanotubes, their interactions in the biological interphase and their general cytotoxicity have become major issues. In spite of their salient properties, major hurdles still exist for their use in biological applications, due to their main characteristics, including their hydrophobic surfaces and tendency to aggregate, as well as their unknown interactions in the cellular interphase. In this Research News, these characteristics of carbon nanotubes, a model nanomaterial, are investigated. Thus, the cytotoxicity of carbon nanotubes, the influence of functionalization, as well as their interactions with different mammalian cell lines are studied. Moreover, suggestions for the improvement of their biocompatibility and the design of biocompatible carbon nanotube‐based systems are provided.