bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changements socio-environnementaux et dynamiques des paysages ruraux le long du gradient bioclimatique nord-sud dans le sud-ouest du Niger (régions de Tillabery et de Dosso)
Authors: Emeterio José Luis San , Alexandre Frédéric , Andrieu Julien , Génin Alain , Mering Catherine 
Published: February 2014

Cet article analyse les changements intervenus dans l’occupation du sol et le couvert végétal au cours des dernières décennies dans un ensemble de villages échelonnés le long du gradient bioclimatique dans le sud-ouest du Niger, depuis la ligne Tillabéry-Filingué au nord jusqu’à Gaya, à la frontière nigéro-béninoise au sud. Des analyses diachroniques d’images ont été réalisées à l’aide d’images satellitaires (CORONA mars et octobre 1965) ou de photographies aériennes (mission IGN mars 1975) comparées à des images actuelles Google Earth. Ces analyses sont confrontées aux entretiens réalisés dans les différents villages ainsi qu’aux relevés sur l’état de la végétation. Si les chercheurs soulignent la reprise des précipitations depuis le milieu des années 1990, ils montrent aussi que le sud-ouest du Niger présente, de façon apparemment paradoxale, une vulnérabilité socio-environnementale accrue. Ce constat semble pouvoir être généralisé à l’échelle de l’ensemble des deux départements. Pourtant, la démarche entreprise amène à nuancer le tableau : lorsque l’on désagrège les données, à l’échelle des villages, la situation apparaît très diversifiée, révélant, indépendamment du gradient bioclimatique nord-sud et, dans une moindre mesure, de la différenciation méridienne imposée par les vallées fossiles (dallols), des situations où la vulnérabilité des populations et des écosystèmes apparaît plus ou moins forte.
Surmonter la crise écologique par un projet spirituel d’ordre supérieur? À partir d’une lecture de Pierre Teilhard de Chardin et de Michel Serres
Authors: Brédif Hervé 
Published: February 2014

La lecture comparée des ouvrages de Michel Serres et de Pierre Teilhard de Chardin permet de penser autrement la crise écologique, en la resituant dans l’évolution longue de la vie sur Terre. Si des différences certaines existent entre ces auteurs, une convergence essentielle se révèle : ils aboutissent à l’idée que l’humanité et la vie elle-même sont invitées à franchir un nouveau palier évolutif. Tout se passe comme si deux totalités, l’Humanité d’une part, la Terre-nature d’autre part, avaient désormais pour horizon commun et souhaitable l’instauration d’une relation authentiquement symbiotique. La réussite de ce qui s’apparente à un projet spirituel d’ordre supérieur n’est cependant pas acquise. Des conditions spécifiques sont requises. Serres met davantage l’accent sur le changement de relations entre le groupe humain et la Terre globale qu’appelle ce projet; il place ses espoirs dans l’établissement d’un contrat tacite entre ces deux entités, contrat fondé en sciences et dont le respect repose sur des éducateurs tiers-instruits. Pour Teilhard, l’enjeu se situe ailleurs : il importe que chaque être humain conserve le goût de poursuivre l’aventure, ce qui suppose qu’il soit convaincu que le processus ne se développera pas à ses dépens et pour le seul profit de quelques élus, de l’espèce ou de ce qui pourrait lui succéder. Les deux penseurs se rejoignent encore dans l’idée qu’une issue positive à la crise actuelle doit privilégier le projet d’ordre supérieur et ses bénéfices potentiels plutôt que la peur ou la menace d’une catastrophe imminente.
An Essential Role for Medullary Thymic Epithelial Cells during the Intrathymic Development of Invariant NKT Cells
Authors: White Andrea J. , Jenkinson William E. , Cowan Jennifer E. , Parnell Sonia M. , Bacon Andrea , Jones Nick D. , Jenkinson Eric J. , Anderson Graham 
Published: February 2014

Abstract
In the thymus, interactions with both cortical and medullary microenvironments regulate the development of self-tolerant conventional CD4+ and CD8+ αβT cells expressing a wide range of αβTCR specificities. Additionally, the cortex is also required for the development of invariant NKT (iNKT) cells, a specialized subset of T cells that expresses a restricted αβTCR repertoire and is linked to the regulation of innate and adaptive immune responses. Although the role of the cortex in this process is to enable recognition of CD1d molecules expressed by CD4+CD8+ thymocyte precursors, the requirements for additional thymus microenvironments during iNKT cell development are unknown. In this study, we reveal a role for medullary thymic epithelial cells (mTECs) during iNKT cell development in the mouse thymus. This requirement for mTECs correlates with their expression of genes required for IL-15 trans-presentation, and we show that soluble IL-15/IL-15Rα complexes restore iNKT cell development in the absence of mTECs. Furthermore, mTEC development is abnormal in iNKT cell–deficient mice, and early stages in iNKT cell development trigger receptor activator for NF-κB ligand–mediated mTEC development. Collectively, our findings demonstrate that intrathymic iNKT cell development requires stepwise interactions with both the cortex and the medulla, emphasizing the importance of thymus compartmentalization in the generation of both diverse and invariant αβT cells. Moreover, the identification of a novel requirement for iNKT cells in thymus medulla development further highlights the role of both innate and adaptive immune cells in thymus medulla formation.
Les pairs-assistants de recherche : pour favoriser l’évolution d’un statut de patients vers celui de citoyens à part entière
Authors: Pelletier Jean-François , Bordeleau Julie , Dumais Alexandre , Renaud Patrice , Rowe Michael 
Published: February 2014

Contexte:Plusieurs écrits scientifiques suggèrent que la participation de personnes en rétablissement en tant que partenaires de recherche représente une valeur scientifique et sociale ajoutée à la recherche en toxicomanie. Toutefois, peu de recherches ont évalué systématiquement les retombées d'une telle participation sur les personnes concernées et selon ces personnes.Objectif:Cet article décrit diverses modalités et degrés de participation possibles en recherche. Les effets de leur participation sont discutés par des personnes qui furent activement parties prenantes au sein de deux projets. Elles furent rencontrées lors de groupes de discussion visant à dégager ce qu'elles pensent que la participation active en recherche peut leur apporter et ce qu'elles pensent qu'elles peuvent apporter à une dynamique de recherche, notamment à titre de pairs-assistants recherche.Résultats:La participation active en recherche favorise une certaine émancipation de la pauvreté, favorise la reconnaissance des compétences, ainsi que l'accès à l'information. Elle représente également l'occasion pour les personnes en question d'assumer des responsabilités et certains thèmes de recherche semblent plus propices que d'autres à des degrés plus élevés de participation. Les deux principaux thèmes qui ont émergés au sujet des effets de la participation des pairsassistants de recherche furent ceux du langage non verbal et de lien d'affinité. C'est-à-dire que leur présence engendre un effet de rétention et d'intérêt plus marqué de la part des autres participants à une étude, étant donné qu'une telle dynamique met ces derniers plus à l'aise de s'exprimer, ce qui se transpose également par la suite dans leur milieu de vie naturel.Conclusion:Les divers niveaux et degrés possibles de participation à la recherche peuvent se combiner et varier dans le temps ou selon les thématiques de recherche proposées. Plus de recherche est nécessaire pour mieux comprendre les enjeux de la participation en recherche et ses effets spécifiques en toxicomanie, ainsi que l'influence des pairs-assistants de recherche sur le rétablissement civique.
ENTREPRENEURIAL EDUCATION AND ECONOMIC COMPETITIVENESS
Authors: Knežević Vladimir , Ivković Dragan 
Published: February 2014

This paper deals with the relation between entrepreneurship education and competitiveness of the national economy. It is based on the assumption that the overall goal of civilization of human society is promotion of a market economy, parliamentary democracy and the rule of law. It is believed that the improvement of competitiveness is of the greatest contribution to the realization of these aspirations as it also requires the development of an integrated market and the establishment of the rule of law, and also provides the material basis and provides an incentive for the development of democratic processes in society. We want to show that the promotion of entrepreneurship education is an important link in the process of improving competitiveness, especially in the middle and high-income countries. Here we analyze the data from the most current report of the World Economic Forum Global Competitiveness Report 2011-2012 of the world and from 2012 to 2013. Using the method of correlation analysis we confirm the remarkable cohesion and coherence of entrepreneurship education and competitiveness of the ten sample countries with different levels of economic development, but which do not belong to the circle of the poor. It confirms the hypothesis that entrepreneurship education is an important element of competitiveness in middle-income and advanced economies. Thus useful to point out their development and education for the Balkan transition economies. Way of improving competitiveness will undoubtedly lead the transformation of education in entrepreneurial terms.
Uticaj nekih socijalnih subjekata na medijsku kulturu
Authors: Rašević Dragana 
Published: February 2014

ApstraktU radu se analizira problem medijske kulture danas na globalnom i regionalnom nivou u odnosu na njene dominantne socijalne subjekte. Medijska kultura u radu podrazumijeva medijski sadržaj i sredstva njegovog emitovanja, visoka tehnološka dostignuća (koja se koriste u procesu prikupljanja, obrade i distribucije informacija) i izvor kulture koju usvajamo. Cilj rada je da ukaže na uticaj dominantnih socijalnih subjekata – ekonomskih i naučnih centara moći – na medijsku kulturu.Razmatraju se problemi koji nastaju kao posljedica djelovanja najmoćnijih determinanti medijske kulture. Posebna pažnja se posvećuje rezultatima istraživanja o slobodi medija američkih nevladinih organizacija Fridom haus i IREKS (IREX - International Research and Exchange Board) ProMedia. Razmatra se položaj i sloboda medija danas u odnosu na proteklih deset godina. Sloboda medija mjeri se ocjenom slobode govora, stepena profesionalnog standarda kvaliteta, pouzdanog i objektivnnog informisanja, ekonomskog poslovanja i nezavisnosti uređivačke politike i djelovanja medijskih institucija u funkciji profesionalnih interesa medija.Konstatuje se da je sve više zemalja u kojima se bilježi pad slobode medija i da je većina zemalja Evrope i Evroazije u nezavidnom ekonomskom položaju, jer nisu slobodni u kreiranju medijskog sadržaja i medijska kultura veoma često zavisi od centara moći koji djeluju u njenom polju.
Experimental and Computational Tools for Analysis of Signaling Networks in Primary Cells
Authors: Schoof Erwin M. , Linding Rune 
Published: February 2014

AbstractCellular information processing in signaling networks forms the basis of responses to environmental stimuli. At any given time, cells receive multiple simultaneous input cues, which are processed and integrated to determine cellular responses such as migration, proliferation, apoptosis, or differentiation. Protein phosphorylation events play a major role in this process and are often involved in fundamental biological and cellular processes such as protein‐protein interactions, enzyme activity, and immune responses. Determining which kinases phosphorylate specific phospho sites poses a challenge; this information is critical when trying to elucidate key proteins involved in specific cellular responses. Here, methods to generate high‐quality quantitative phosphorylation data from cell lysates originating from primary cells, and how to analyze the generated data to construct quantitative signaling network models, are presented. These models can subsequently be used to guide follow‐up in vitro/in vivo validation studies. Curr. Protoc. Immunol. 104:11.11.1‐11.11.23. © 2014 by John Wiley & Sons, Inc.
Three‐Phase Trickle‐Bed Reactors
Authors: Dudukovic Milorad P. , Kuzeljevic Željko V. , Combest Daniel P. 
Published: February 2014

This chapter reviews the art and science involved in understanding the multiscale multiphase phenomena that affect the performance of trickle bed reactors. Their application areas, the traditional approach to their design and scaleup, and some commonly encountered problems in practice are discussed. The foundations for rational scaleup are introduced. The recent attempts to develop a multiscale science‐based approach to scale up and design of these reactors is summarized at the end.The article contains sections titled:1.Introduction2.Design2.1.Flow Regimes2.2.Flow Distribution2.3.Pressure Drop2.4.Liquid Holdup2.5.Catalyst Wetting and Liquid–Solid Contacting2.6.Residence Time Distributions2.7.Heat Transfer and Thermal Stability3.Modeling and Analysis3.1.Reactor Models3.2.Hydrodynamic and Computational Fluid Dynamic Models3.3.CFD Models of Trickle Beds4.Trickle‐bed Reactor Scaleup5.Reactor Troubleshooting6.AcknowledgmentReferences
Maar‐diatreme geometry and deposits: Subsurface blast experiments with variable explosion depth
Authors: Graettinger A. H. , Valentine G. A. , Sonder I. , Ross P.‐S. , White J. D. L. , Taddeucci J. 
Published: February 2014

AbstractBasaltic maar‐diatreme volcanoes, which have craters cut into preeruption landscapes (maars) underlain by downward‐tapering bodies of fragmental material commonly cut by hypabyssal intrusions (diatremes), are produced by multiple subsurface phreatomagmatic explosions. Although many maar‐diatremes have been studied, the link between explosion dynamics and the resulting deposit architecture is still poorly understood. Scaled experiments employed multiple buried explosions of known energies and depths within layered aggregates in order to assess the effects of explosion depth, and the morphology and compaction of the host on the distribution of host materials in resulting ejecta, the development of subcrater structures and deposits, and the relationships between them. Experimental craters were 1–2 m wide. Analysis of high‐speed video shows that explosion jets had heights and shapes that were strongly influenced by scaled depth (physical depth scaled against explosion energy) and by the presence or absence of a crater. Jet properties in turn controlled the distribution of ejecta deposits outside the craters, and we infer that this is also reflected in the diverse range of deposit types at natural maars. Ejecta were dominated by material that originated above the explosion site, and the shallowest material was dispersed the farthest. Subcrater deposits illustrate progressive vertical mixing of host materials through successive explosions. We conclude that the progressive appearance of deeper‐seated material stratigraphically upward in deposits of natural maars probably records the length and time scale for upward mixing through multiple explosions with ejection by shallow blasts, rather than progressive deepening of explosion sites in response to draw down of aquifers.
Advanced infrared sounder subpixel cloud detection with imagers and its impact on radiance assimilation in NWP
Authors: Wang Pei , Li Jun , Li Jinlong , Li Zhenglong , Schmit Timothy J. , Bai Wenguang 
Published: February 2014

AbstractAccurate cloud detection is very important for infrared (IR) radiance assimilation; improved cloud detection could reduce cloud contamination and hence improve the assimilation. Although operational numerical weather prediction (NWP) centers are using IR sounder radiance data for cloud detection, collocated high spatial resolution imager data could help sounder subpixel cloud detection and characterization. IR sounder radiances with improved cloud detection using Atmospheric Infrared Sounder (AIRS)/Moderate Resolution Imaging Spectroradiometer (MODIS) were assimilated for Hurricane Sandy (2012). Forecast experiments were run with Weather Research and Forecasting (WRF) as the forecast model and the Three‐Dimensional Variational Assimilation (3DVAR)‐based Gridpoint Statistical Interpolation (GSI) as the analysis system. Results indicate that forecasts of both hurricane track and intensity are substantially improved when the collocated high spatial resolution MODIS cloud mask is used for AIRS subpixel cloud detection for assimilating radiances. This methodology can be applied to process Crosstrack Infrared Sounder (CRIS)/Visible Infrared Imaging Radiometer Suite (VIIRS) onboard Suomi‐NPOESS Preparatory Project (NPP)/Joint Polar Satellite System (JPSS) and Infrared Atmospheric Sounding Interferometer (IASI)/Advanced Very High Resolution Radiometer (AVHRR) onboard the Metop series for improved radiance assimilation in NWP.
Development and validation of inversion technique for substorm current wedge using ground magnetic field data
Authors: Chu Xiangning , Hsu Tung‐Shin , McPherron Robert L. , Angelopoulos Vassilis , Pu Zuyin , Weygand James J. , Khurana Krishan , Connors Martin , Kissinger Jennifer , Zhang Hui , Amm Olaf 
Published: February 2014

AbstractThe classic substorm current wedge model represents ground and space magnetic perturbations measured during substorms. We have developed an inversion technique to calculate parameters determining the intensity and geometry of the current system using magnetic field data at midlatitudes. The current wedge consists of four segments: a sheet‐like field‐aligned current downward to the ionosphere postmidnight, a westward current across the auroral bulge, an upward sheet‐like current from the westward surge premidnight, and an eastward current in the equatorial plane. The model has five parameters including the current strength, the locations, and breadths of the two field‐aligned current sheets. Simultaneous changes in the ring current are represented by the superposition of a symmetric ring current and a partial ring current characterized by three additional parameters. Parameters of the model are determined as a function of time based on midlatitude ground magnetometers, using realistic field lines and accounting for Earth's induction. The model is validated by a variety of techniques. First, the model predicts more than 80% of the variance in the observations. Second, the intensity of the current wedge and the ring current follows the same trends of the westward electrojet and the ring current indices. Third, the intensity of the westward electrojet agrees extremely well with the intensity of the current wedge. Finally, spacecraft observations of the aurora correspond with the evolution deduced from the model. This model of the substorm current wedge provides a valuable tool for the study of substorm development and its relation to phenomena in space.
Harmonic waves and sheath rectification in type III solar radio bursts
Authors: Graham D. B. , Cairns Iver H. , Malaspina D. M. 
Published: February 2014

AbstractIn type III solar radio bursts and planetary foreshocks, Langmuir waves are produced by electron beams and converted partially to radio waves by linear and nonlinear processes. Lower amplitude second harmonic electric fields are observed simultaneously during the most intense Langmuir wave events in type III source regions. The electric fields at the harmonic frequencies can arise from various mechanisms, such as radio wave emission by either coalescence or antenna mechanisms, nonlinear currents, harmonics of Langmuir waves, electron trapping in Langmuir wave potentials, and Langmuir wave rectification at the sheath surrounding the spacecraft, or they can result from instrumental harmonics. In this paper the relative powers and electric field vectors of Langmuir waves and the harmonic fields are compared for multiple events. The structure of the harmonic field is shown to be determined by the Langmuir waveform, but the harmonic field direction is typically closely aligned with the solar wind flow. The magnitude, structure, and orientation of the harmonic fields is used to determine which processes are responsible. It is shown that the dominant process generating the observed harmonic fields is Langmuir wave rectification at the sheath surrounding the spacecraft.
Preliminary interpretation of the REMS pressure data from the first 100 sols of the MSL mission
Authors: Haberle R. M. , Gómez‐Elvira J. , de la Torre Juárez M. , Harri A.‐M. , Hollingsworth J. L. , Kahanpää H. , Kahre M. A. , Lemmon M. , Martín‐Torres F. J. , Mischna M. , Moores J. E. , Newman C. , Rafkin S. C. R. , Rennó N. , Richardson M. I. , Rodríguez‐Manfredi J. A. , Vasavada A. R. , Zorzano‐Mier M.‐P. ,   REMS/MSL Science Teams
Published: February 2014

AbstractWe provide a preliminary interpretation of the Rover Environmental Monitoring Station (REMS) pressure data from the first 100 Martian solar days (sols) of the Mars Science Laboratory mission. The pressure sensor is performing well and has revealed the existence of phenomena undetected by previous missions that include possible gravity waves excited by evening downslope flows, relatively dust‐free convective vortices analogous in structure to dust devils, and signatures indicative of the circulation induced by Gale Crater and its central mound. Other more familiar phenomena are also present including the thermal tides, generated by daily insolation variations, and the CO2 cycle, driven by the condensation and sublimation of CO2 in the polar regions. The amplitude of the thermal tides is several times larger than those seen by other landers primarily because Curiosity is located where eastward and westward tidal modes constructively interfere and also because the crater circulation amplifies the tides to some extent. During the first 100 sols tidal amplitudes generally decline, which we attribute to the waning influence of the Kelvin wave. Toward the end of the 100 sol period, tidal amplitudes abruptly increased in response to a nearby regional dust storm that did not expand to global scales. Tidal phases changed abruptly during the onset of this storm suggesting a change in the interaction between eastward and westward modes. When compared to Viking Lander 2 data, the REMS daily average pressures show no evidence yet for the 1–20 Pa increase expected from the possible loss of CO2 from the south polar residual cap.
Charged particle spectra obtained with the Mars Science Laboratory Radiation Assessment Detector (MSL/RAD) on the surface of Mars
Authors: Ehresmann Bent , Zeitlin Cary , Hassler Donald M. , Wimmer‐Schweingruber Robert F. , Böhm Eckart , Böttcher Stephan , Brinza David E. , Burmeister Sönke , Guo Jingnan , Köhler Jan , Martin Cesar , Posner Arik , Rafkin Scot , Reitz Günther 
Published: February 2014

AbstractThe Radiation Assessment Detector (RAD)—situated inside the Mars Science Laboratory's Curiosity rover—is the first ever instrument to measure the energetic particle radiation environment on the surface of Mars. To fully understand the influence of this surface radiation field in terms of potential hazard to life, a detailed knowledge of its composition is necessary. Charged particles are a major component of this environment, both galactic cosmic rays propagating to the Martian surface and secondary particles created by interactions of these cosmic rays with the atoms of the Martian atmosphere and soil. Here we present particle fluxes for a wide range of ion species, providing detailed energy spectra in the low‐energy range (up to several hundred MeV/nucleon particle energy), and integral fluxes for higher energies. In addition to being crucial for the understanding of the hazards of this radiation to possible future manned missions to Mars, the data reported here provide valuable input for evaluating and validating particle transport models currently used to estimate the radiation environment on Mars and elsewhere in space. It is now possible for the first time to compare model results for expected surface particle fluxes with actual ground‐based measurements.