bluuebunny/crossref_metadata_2025_split huggingface dataset:
Température et phénomènes biochimiques dans la dissolution du calcaire
Authors: Drogue C. , Plegat R. 
Published: April 2014

Abstract
Generally, it is admitted that the karstification phenomenous has a great activity in cold regions. But it is shown that the pressure of carbonic gas has a most importance in the atmosphere than, it has in the temperature of the solubility of the gas below water.
Waters are very corrosive in hot and wet climates.
Réflexions sur les relations entre le karst de surface et le karst profond établies sur quelques exemples
Authors: Rouire J. , Rousset C. 
Published: April 2014

Résumé.
L'étude de quelques karsts du S.E. de la France permet de dégager un point de vue synthétique sur les relations entre karst de surface et karst profond. Dans le cas général, il y a indépendance totale entre les phénomènes de surface (dus à l'action des agents atmosphériques) et les phénomènes de la spéléogénèse. Les liens apparents sont dus à la superposition des zones ou à la communauté des facteurs géologiques (structures et lithologie). Lapiaz (y compris avens de corrosion descendante) et dolines de corrosion sont des formes de surface. Dolines et avens d'effondrement, avens de creusement ascendant se rattachent au karst profond par leur origine et évolution, de même que les grandes formes en creux (poljés s.s.). Une partie du karst profond se répercute donc jusqu'à la surface. Il est normal que les communications entre les zones d'évolution indépendante soient aléatoires.
La division sociale de l'espace urbain : méthodes et procédés d'analyse
Authors: Roncayolo Marcel 
Published: April 2014

Résumé.
Le thème choisi, la division sociale de l'espace urbain, suscite à la fois une démarche théorique et le traitement systématique de données. L'analyse qui a été menée à partir de l'exemple de Marseille est volontairement partielle. Écartant, par simple hypothèse, la référence immédiate à une théorie unitaire des espaces urbains, elle s'efforce d'établir ce que les distinctions sociales à l'intérieur de la ville ont d'original, de non réductible. De même, à la mobilisation de données multiples, inégales en valeur, en pertinence et souvent peu raccordables, on a préféré l'étude d'une série simple - la répartition des catégories socio-professionnelles dans la ville en 1962. En appliquant l'analyse factorielle - ou mieux plusieurs types d'analyse factorielle - au traitement de ces données, on saisit néanmoins les contraintes, les limites, les déformations qui sont liées à ces procédés d'études, autant que leur efficacité ; moins satisfaisant, en termes mathématiques, le calcul de distances permet d'apprécier l'évolution entre deux recensements.
L'utilisation de ces analyses ne dispense ni d'une réflexion sur la nature des liens de causalité qui unissent entre eux les phénomènes, ni de l' élaboration de nouvelles données, tenant à la morphologie, aux processus de croissance des espaces urbains et à la répartition des groupes sociaux. En ce sens l'emploi de techniques déjà banales dans les autres sciences sociales n'établit pas de rupture significative avec d'autres démarches du géographe, et conduit à chercher des outils mathématiques les mieux adaptés à celle-ci.
Réflexions sur les pluies au Venezuela
Authors: Pagney Pierre 
Published: April 2014

Résumé.
L'abondance moyenne des pluies au Venezuela va en s'aggravant du Nord (la façade caraïbe est particulièrement sèche) au Sud. Sauf en Amazonie et en Guyanne vénézuélienne, ces pluies s'inscrivent dans un rythme tropical. L'inhibition d'hiver résulte de la présence de hautes pressions épaisses prenant racine sur l'Atlantique nord-tropical et la mer Caraïbe. Des nuances interviennent cependant qui permettent de distinguer principalement quatre familles de régimes : régime des « Iles sous le vent » à pluies de début d'hiver, du Maracaïbo à double pointe de saison chaude (mai et octobre), les Llanos à exaltation pluviométrique unique (cœur de l'hivernage), de façade caraïbe, régime mixte à pointes d'hiver et d'été. Les exaltations d'hiver, de mai et d'octobre font intervenir des processus extratropicaux associés, ou non, à l'air équatorial dans un cadre d'échanges méridiens. Les pluies du cœur de l'été posent le problème de la nature et du dynamisme de la C.I.T. pour laquelle les inconnues sont, semble-t-il, du côté de l'Amazonie.
Les transformations récentes du marché mondial de la banane (1950-1970)
Authors: Maillard J.-Cl. 
Published: April 2014

Résumé.
Le marché bananier prend dans les années 1950-1970 un nouveau visage. La vulgarisation, à la place de la Gros-Michel, des variétés Cavendish, plus productives, mais aux fruits plus fragiles, impose en effet, à tous les niveaux, de la production a la vente, un important effort de renouvellement. La reprise de la production centre-américaine qu'elle favorise, confirme l'état de surproduction né, dès la fin des années 50, du développement spectaculaire des plantations équatoriennes. Elle amène producteurs et consommateurs à l'idée assez neuve d'une concertation internationale en ce domaine d'où résulte, depuis 1964, une série de « Conférences bananières» tenue sous l'égide de la F.A.O. L'ouverture de nouveaux marchés, et particulièrement du marché japonais, contribue parallèlement à un certain assainissement de la situation. Le développement de la consommation dans les pays socialistes ouvre pour l'avenir d'autres perspectives.
Emmanuel de Martonne et la géographie roumaine
Authors: Morariu Tiberiu 
Published: April 2014

Abstract.
The Romanian geographic historiography records a great personality, that of prof. E. de Martonne, who, for thirty-five years of beneficial scholarly research, has dedicated himself to the Romanian land and who has written more than seventy scholarly works, among which are two doctoral theses entitled « La Valachie » and « L'évolution morphologique des Alpes de Transylvanie ».
Four main aspects define the coordinates of his activity, which coexist intrinsically. Predominant is, however, the scholarly research which comprises almost all the Romanian provinces, rendering the basis of regional study in examining the Romanian provinces. The sphere of scholarly interest includes almost all the domains of geography, beginning with geomorphology and ending with human geography.
The second aspect of prof. De Martonne' s activity is closely connected with the organizing, together with prof. G. Vâlsan, of modern geographical higher education in Cluj. Thus, his name enters the gallery of the greatest professors the Transylvanean University has ever had. De Martonne was a steady fighter for a close mutual relationship between France and Romania, thus making Romania's hopes and aspirations known to the Western world. We cannot neglect, then, his contribution to the tracing of the borders of our country in 1918, at the Peace Conference from Paris, which meant, in fact, Romania's come-back « ... to its natural and legitimate destinies ». He has been awarded Doctor Honoris Causa of the University of Cluj, Honorary Citizen of the Transylvanean capital, and as an apotheosis of his activity he has been awarded « The Order of Romania's Star » as « The Great Cross ».
De Martonne's name, which was given to one of the streets close to the University of Cluj, will for ever be linked with the development of geography in our country.
La décentralisation industrielle en France de 1954 à 1971
Authors: Bastié J. 
Published: April 2014

Abstract.
Industrial decentralization in France, between 1954 and the end of 1971, is responsible for the creation, out of the Paris region, of one half-million fobs, out of which 50 % are due to 82 large companies.
In spite of financial aids set up by the State to help regions which most needed these creations, about half of the operations have been carried out without any aid from public powers, and spontaneously towards other regions, mainly the closest to Paris, in first the Bassin Parisien, especially in its western part, Decentralization participated greatly in the industrial development of the « région de programme » : Normandie, Bretagne, Pays de la Loire, Picardie and Centre.
The farther they are from Paris, the less numerous small welcoming establishments are, and the less important the percentage of created jobs in samll towns gets, and the more numerous great establishments and big towns concerned by decentralization are.
Requirement of Calcineurin Aβ for the Survival of Naive T Cells
Authors: Manicassamy Santhakumar , Gupta Sonal , Huang Zhaofeng , Molkentin Jeffery D. , Shang Weirong , Sun Zuoming 
Published: April 2014

Abstract
Calcineurin (Cn) is a Ca2+/calmodulin-dependent phosphatase that dephosphorylates and activates NFAT, a transcription factor essential for T cell activation. T lymphocytes predominantly express the calcineurin Aβ (CnAβ) isoform, and the deletion of the CnAβ gene results in defective T cell proliferation and IL-2 production in response to TCR stimulation. In this study, we show that CnAβ enhances the spontaneous survival of naive T cells by maintaining high levels of Bcl-2, a critical homeostatic survival factor for naive T cells. T cells obtained from CnAβ−/− mice displayed accelerated spontaneous apoptosis. The observed apoptosis of the CnAβ−/− T cells was prevented by IL-7 and IL-15, two cytokines critical for the homeostatic survival of naive T cells. Furthermore, CD4+ or CD8+ single positive CnAβ−/− thymocytes also underwent accelerated apoptosis. However, no obvious difference in the apoptosis of CD4+CD8+ double positive thymocytes was observed between CnAβ−/− and wild-type mice, suggesting a specific function of CnAβ in the survival of single positive T cells. Bcl-2 levels were found to be significantly lower in CnAβ−/− T cells. Transgenic expression of Bcl-xL restored the survival of the CnAβ−/− T cells. Thus, in addition to its role in mediating TCR signals essential for T cell activation, CnAβ is also required for the homeostatic survival of naive T cells.
Proliferating CD4+ T Cells Undergo Immediate Growth Arrest upon Cessation of TCR Signaling In Vivo
Authors: Yarke Cory A. , Dalheimer Stacy L. , Zhang Na , Catron Drew M. , Jenkins Marc K. , Mueller Daniel L. 
Published: April 2014

Abstract
To investigate the role of TCR signaling in the exit of CD4+ T cells from cell cycle, we took advantage of a low frequency TEa T cell adoptive transfer technique as well as the Y-Ae mAb to interrupt Ag/MHC recognition before the completion of clonal expansion. Termination of TCR signaling after 36 h of Ag exposure caused an immediate reduction in cell size and deceleration of G1—&gt;SG2M phase cell cycle progression. As a consequence, clonal expansion in the absence of durable TCR signaling decreased by two-thirds. Thus, CD4+ T cells scan for the presence Ag throughout their clonal expansion response, and continuously adjust their rate of cell growth and G1—&gt;S phase transition to match their intensity of TCR signaling.
Immune Modulation by the Human Cytomegalovirus-Encoded Molecule UL18, a Mystery Yet to Be Solved
Authors: Wagner Claudia S. , Ljunggren Hans-Gustaf , Achour Adnane 
Published: April 2014

Abstract
Human cytomegalovirus infects human populations at a high frequency worldwide. During the long coevolution of virus and host, a fine balance has developed between viral immune evasion strategies and defense mechanisms of the immune system. Human cytomegalovirus encodes multiple proteins involved in the evasion of immune recognition, among them UL18, a MHC class I homologue. Despite almost 20 years of research and the discovery of a broadly expressed inhibitory receptor for this protein, its function in immune modulation is not clear yet. Recent data suggest that besides inhibitory effects on various immune cells, UL18 may also act as an activating component during CMV infection. In this review, we provide an overview of the biology of UL18 and discuss several attempts to shed light on its function.
Human T Cells That Are Able to Produce IL-17 Express the Chemokine Receptor CCR6
Authors: Singh Satya P. , Zhang Hongwei H. , Foley John F. , Hedrick Michael N. , Farber Joshua M. 
Published: April 2014

AbstractSome pathways of T cell differentiation are associated with characteristic patterns of chemokine receptor expression. A new lineage of effector/memory CD4+ T cells has been identified whose signature products are IL-17 cytokines and whose differentiation requires the nuclear receptor, RORγt. These Th17 cells are critical effectors in mouse models of autoimmune disease. We have analyzed the association between chemokine receptor expression and IL-17 production for human T cells. Activating cord blood (naive) CD4+ T cells under conditions driving Th17 differentiation led to preferential induction of CCR6, CCR9, and CXCR6. Despite these data, we found no strong correlation between the production of IL-17 and expression of CCR9 or CXCR6. By contrast, our analyses revealed that virtually all IL-17-producing CD4+ T cells, either made in our in vitro cultures or found in peripheral blood, expressed CCR6, a receptor found on ∼50% of CD4+ memory PBL. Compared with CD4+CD45RO+CCR6− cells, CD4+CD45RO+CCR6+ cells contained at least 100-fold more IL-17A mRNA and secreted 100-fold more IL-17 protein. The CCR6+ cells showed a similar enrichment in mRNA for RORγt. CCR6 was likewise expressed on all IL-17-producing CD8+ PBL. CCR6 has been associated with the trafficking of T, B, and dendritic cells to epithelial sites, but has not been linked to a specific T cell phenotype. Our data reveal a fundamental feature of IL-17-producing human T cells and a novel role for CCR6, suggesting both new directions for investigating IL-17-related immune responses and possible targets for preventing inflammatory injury.
The Inhibitory HVEM-BTLA Pathway Counter Regulates Lymphotoxin β Receptor Signaling to Achieve Homeostasis of Dendritic Cells
Authors: De Trez Carl , Schneider Kirsten , Potter Karen , Droin Nathalie , Fulton James , Norris Paula S. , Ha Suk-won , Fu Yang-Xin , Murphy Theresa , Murphy Kenneth M. , Pfeffer Klaus , Benedict Chris A. , Ware Carl F. 
Published: April 2014

Abstract
Proliferation of dendritic cells (DC) in the spleen is regulated by positive growth signals through the lymphotoxin (LT)-β receptor; however, the countering inhibitory signals that achieve homeostatic control are unresolved. Mice deficient in LTα, LTβ, LTβR, and the NFκB inducing kinase show a specific loss of CD8− DC subsets. In contrast, the CD8α− DC subsets were overpopulated in mice deficient in the herpesvirus entry mediator (HVEM) or B and T lymphocyte attenuator (BTLA). HVEM- and BTLA-deficient DC subsets displayed a specific growth advantage in repopulating the spleen in competitive replacement bone marrow chimeric mice. Expression of HVEM and BTLA were required in DC and in the surrounding microenvironment, although DC expression of LTβR was necessary to maintain homeostasis. Moreover, enforced activation of the LTβR with an agonist Ab drove expansion of CD8α− DC subsets, overriding regulation by the HVEM-BTLA pathway. These results indicate the HVEM-BTLA pathway provides an inhibitory checkpoint for DC homeostasis in lymphoid tissue. Together, the LTβR and HVEM-BTLA pathways form an integrated signaling network regulating DC homeostasis.
Cutting Edge: Engagement of NKG2A on CD8+ Effector T Cells Limits Immunopathology in Influenza Pneumonia
Authors: Zhou Jing , Matsuoka Mitsuo , Cantor Harvey , Homer Robert , Enelow Richard I. 
Published: April 2014

Abstract
Influenza pneumonia results in considerable lung injury, a significant component of which is mediated by CD8+ T cell Ag recognition in the distal airways and alveoli. TNF-α produced by Ag-specific CD8+ T cells appears primarily responsible for this immunopathology, and we have examined the negative regulation of CD8+ TNF production by CD94/NKG2A engagement with its receptor, Qa-1b. TNF production by antiviral CD8+ T cells was significantly enhanced by NKG2A blockade in vitro, and mice deficient in the NKG2A ligand, Qa-1b, manifested significantly greater pulmonary pathology upon CD8+ T cell-mediated clearance in influenza pneumonia. Furthermore, blockade of NKG2A ligation resulted in the enhancement of lung injury induced by CD8+ effector cell recognition of alveolar Ag in vivo in the absence of infectious virus. These data demonstrate that CD94/NKG2A transduces a biologically important signal in vivo to activated CD8+ T cells that limits immunopathology in severe influenza infection.
Hyperacute Rejection by Anti-Gal IgG1, IgG2a, and IgG2b Is Dependent on Complement and Fc-γ Receptors
Authors: Ding Jin Wen , Zhou Tingting , Zeng Huasong , Ma Lianli , Verbeek J. Sjef , Yin Dengping , Shen Jikun , Chong Anita S. 
Published: April 2014

Abstract
We have previously reported that anti-Gal-α1,3Gal (Gal) IgG3 mAbs mediate a classical complement-dependent hyperacute rejection (HAR), while anti-Gal IgG1 mAbs mediate HAR that is dependent on complement, the Fc-γ receptors FcγRII/III (CD32/CD16), and NK cells. IgG2a and IgG2b subclasses can activate complement and have FcγR binding properties in vitro. Whether these IgG subclasses can mediate HAR in vivo and the mechanisms by which they would do so are not known. In this study, we isolated spontaneous IgG switch mutants from an anti-Gal IgG1 hybridoma. In vitro complement-mediated hemolytic assays with mouse complement indicate that both anti-Gal IgG2a and IgG2b mAbs were more potent compared with the parent anti-Gal IgG1. In vivo administration of anti-Gal IgG2a and IgG2b mAbs into Gal−/− mice induced HAR of rat cardiac xenografts. HAR induced by anti-Gal IgG2a and IgG2b was dependent on complement activation and the presence of NK cells. Using FcγRIII-deficient (Gal−/−CD16−/−) recipients, we observed that HAR mediated by different anti-Gal IgG subclasses was variably dependent on FcγRIII, with IgG1 &gt; IgG2b ≫ IgG2a = IgG3. Using FcγRI-deficient (Gal−/−CD64−/−) recipients, we observed that HAR mediated by anti-Gal IgG1, IgG2a, and IgG2b, but not by anti-Gal IgG3, was dependent on FcγRI. Collectively, these studies demonstrate the necessity and sufficiency of complement in IgG3-mediated HAR and the necessity of both complement and FcγR, especially FcγRI, in IgG1-, IgG2a-, and IgG2b-mediated HAR.
IL-15 Treatment during Acute Simian Immunodeficiency Virus (SIV) Infection Increases Viral Set Point and Accelerates Disease Progression despite the Induction of Stronger SIV-Specific CD8+ T Cell Responses
Authors: Mueller Yvonne M. , Do Duc H. , Altork Susan R. , Artlett Carol M. , Gracely Edward J. , Katsetos Christos D. , Legido Agustin , Villinger Francois , Altman John D. , Brown Charles R. , Lewis Mark G. , Katsikis Peter D. 
Published: April 2014

AbstractIn this study, we examined the effect of in vivo treatment of acutely SIV-infected Mamu-A*01+ rhesus macaques with IL-15. IL-15 treatment during acute infection increased viral set point by 3 logs and accelerated the development of simian AIDS in two of six animals with one developing early minimal lesion SIV meningoencephalitis. Although IL-15 induced a 2- to 3-fold increase in SIV-specific CD8+ T cell and NK cell numbers at peak viremia and reduced lymph node (LN) SIV-infected cells, this had no impact on peak viremia and did not lower viral set point. At viral set point, however, activated SIV-specific CD8+ T cells and NK cells were reduced in the blood of IL-15-treated animals and LN SIV-infected cells were increased. Week 30 LN from IL-15-treated animals had significantly increased Gag-specific CD8+ T cell numbers, whereas total cell, lymphocyte, and CD4+ T cell numbers were reduced. IL-15 treatment significantly reduced anti-SIV Ab concentrations at week 3 and viral set point. IL-15 increased Ki-67+CD4+ T cells at week 1 of treatment and reduced blood CCR5+ and CD45RA−CD62L− CD4+ T cells. The frequency of day 7 Ki-67+CD4+ T cells strongly correlated with viral set point. These findings suggest that CD4+ T cell activation during acute infection determines subsequent viral set point and IL-15 treatment by increasing such activation elevates viral set point. Finally, IL-15-treated acutely SIV-infected primates may serve as a useful model to investigate the poorly understood mechanisms that control viral set point and disease progression in HIV infection.
Maintenance of Long-Lived Plasma Cells and Serological Memory Despite Mature and Memory B Cell Depletion during CD20 Immunotherapy in Mice
Authors: DiLillo David J. , Hamaguchi Yasuhito , Ueda Yoshihiro , Yang Kaiyong , Uchida Junji , Haas Karen M. , Kelsoe Garnett , Tedder Thomas F. 
Published: April 2014

Abstract
CD20 mAb-mediated B cell depletion is an effective treatment for B cell malignancies and some autoimmune diseases. However, the full effects of B cell depletion on natural, primary, and secondary Ab responses and the maintenance of Ag-specific serum Ig levels are largely unknown. The relationship between memory B cells, long-lived plasma cells, and long-lived humoral immunity also remains controversial. To address the roles of B cell subsets in the longevity of humoral responses, mature B cells were depleted in mice using CD20 mAb. Peritoneal B cell depletion reduced natural and Ag-induced IgM responses. Otherwise, CD20+ B cell depletion prevented humoral immune responses and class switching and depleted existing and adoptively transferred B cell memory. Nonetheless, B cell depletion did not affect serum Ig levels, Ag-specific Ab titers, or bone marrow Ab-secreting plasma cell numbers. Coblockade of LFA-1 and VLA-4 adhesion molecules temporarily depleted long-lived plasma cells from the bone marrow. CD20+ B cell depletion plus LFA-1/VLA-4 mAb treatment significantly prolonged Ag-specific plasma cell depletion from the bone marrow, with a significant decrease in Ag-specific serum IgG. Collectively, these results support previous claims that bone marrow plasma cells are intrinsically long-lived. Furthermore, these studies now demonstrate that mature and memory B cells are not required for maintaining bone marrow plasma cell numbers, but are required for repopulation of plasma cell-deficient bone marrow. Thereby, depleting mature and memory B cells does not have a dramatic negative effect on preexisting Ab levels.
Targeting HIV-1 Gag into the Defective Ribosomal Product Pathway Enhances MHC Class I Antigen Presentation and CD8+ T Cell Activation
Authors: Goldwich Andreas , Hahn Sabine S. C. , Schreiber Sandra , Meier Stefanie , Kämpgen Eckhart , Wagner Ralf , Lutz Manfred B. , Schubert Ulrich 
Published: April 2014

AbstractThe main source for endogenous peptides presented by the MHC class I (MHC-I) pathway are de novo-synthesized proteins which are degraded via the ubiquitin proteasome pathway. Different MHC-I Ag pools can be distinguished: first, short-lived defective ribosomal products, which are degraded in concert with or shortly after their synthesis, and, second, functional proteins that enter the standard protein life cycle. To compare the contribution of these two Ag sources to the generation of MHC-I-presented peptides, we established murine cell lines which express as a model Ag the HIV-1 Gag polyprotein fused to ubiquitin (Ub) carrying the epitope SIINFEKL (SL). Gag was expressed either in its wild-type form (UbMGagSL) or as a variant UbRGagSL harboring an N-end rule degron signal. Although UbRGagSL displayed wild-type protein stability, its inherent defective ribosomal products rate observed after proteasome shutdown was increased concomitant with enhanced presentation of the SL epitope. In addition, UbRGagSL induces enhanced T cell stimulation of SL-specific B3Z hybridoma cells as measured in vitro and of adoptively transferred TCR-transgenic OT-1 T cells in vivo. Furthermore, an elevated frequency of SL-specific T cells was detected by IFN-γ ELISPOT after immunization of naive C57BL/6 mice with UbRGagSL/EL4 cells. These results further underline the role of the defective ribosomal product pathway in adaptive immunity.