182 research outputs found
Analyse de la tùche d'un pilote de Rafale à l'aide d'une HTA étendue à la gestion des modes dégradés
International audienceCette communication prĂ©sente l'adaptation de la mĂ©thode HTA pour l'Ă©tude d'une situation dynamique incertaine et coopĂ©rative : une mission militaire aĂ©rienne rĂ©alisĂ©e par un pilote de chasse Ă bord d'un avion Rafale. Les boucles - perception, reprĂ©sentation, action - caractĂ©ristiques de la gestion d'une situation dynamique sont intĂ©grĂ©es dans la HTA sous la forme de buts de haut-niveau. La mise en Ă©vidence de plans contingents permet de rendre compte de la gestion de l'incertitude et des situations dĂ©gradĂ©es. Enfin, la coopĂ©ration multiagents est dĂ©crite par un codage des tĂąches de communication prĂ©cisant la fonction, l'objet et les acteurs impliquĂ©s. Finalement, les intĂ©rĂȘts et les limites de l'application de la mĂ©thode HTA dans le cadre des situations dynamiques sont discutĂ©s
Scientific Drilling
Integrated Ocean Drilling Program (IODP) Expedition 340T returned to the 1.4-km-deep Hole U1309D at Atlantis Massif to carry out borehole logging including vertical seismic profiling (VSP). Seismic, resistivity, and temperature logs were obtained throughout the geologic section in the footwall of this oceanic core complex. Reliable downhole temperature measurements throughout and the first seismic coverage of the 800â1400 meters below seafloor (mbsf) portionof the section were obtained. Distinct changes in velocity, resistivity, and magnetic susceptibility characterize the boundaries of altered, olivine-rich troctolite intervals within the otherwise dominantly gabbroic se-quence. Some narrow fault zones also are associated with downhole resistivity or velocity excursions. Small deviations in temperature were measured in borehole fluid adjacent to known faults at 750 mbsf and 1100 mbsf. This suggests that flow of seawater remains active along these zones of faulting and rock alteration. Vertical seismic profile station coverage at zero offsetnow extends the full length of the hole, including the uppermost 150 mbsf, where detachment processes are expected to have left their strongest imprint. Analysis of wallrock properties, together with alteration and structural characteristics of the cores from Site U1309, highlights the likely interplay between lithology, structure, lithospheric hydration, and core complex evolution
Innovative Policies for Alpine Towns
Knjiga Inovativne politike za alpska mesta predstavlja rezultate projekta CAPACities, v katerem smo preuÄevali vlogo mest v alpskem svetu. Pri tem smo se osredotoÄili na definicijo malih alpskih mest, njihovo vpetost v policentriÄni razvojni koncept, bistveni poudarek pa je bil na njihovi konkurenÄnosti in privlaÄnosti. Teoretske podlage smo nadgradili z analizo razpoloĆŸljivih podatkov, ĆĄe pomembnejĆĄe pa so bile aktivnosti v pilotnih obmoÄjih, s katerimi smo skuĆĄali ugotovitve prenaĆĄati v prakso. Predstavljene specifike pilotnih obmoÄij in tam izvedene aktivnosti so nam bile v pomoÄ pri izdelavi smernic in orodij za spodbujanje razvoja malih alpskih mest
Geophysical signatures of past and present hydration within a young oceanic core complex
Borehole logging at the Atlantis Massif oceanic core complex provides new information on the relationship between the physical properties and the lithospheric hydration of a slow-spread intrusive crustal section. Integrated Ocean Drilling Program Hole U1309D penetrates 1.4âkm into the footwall to an exposed detachment fault on the 1.2âMa flank of the mid-Atlantic Ridge, 30°N. Downhole variations in seismic velocity and resistivity show a strong correspondence to the degree of alteration, a recorder of past seawater circulation. Average velocity and resistivity are lower, and alteration is more pervasive above a fault around 750âm. Deeper, these properties have higher values except in heavily altered ultramafic zones that are several tens of meters thick. Present circulation inferred from temperature mimics this pattern: advective cooling persists above 750âm, but below, conductive cooling dominates except for small excursions within the ultramafic zones. These alteration-related physical property signatures are probably a characteristic of gabbroic cores at oceanic core complexes
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Near-offset vertical seismic experiments during leg 204
Three successful vertical seismic profiles (VSPs) were acquired during
Ocean Drilling Program (ODP) Leg 204 at South Hydrate Ridge. The
data confirm earlier results from ocean bottom seismometer data and
analysis of moveout from common midpoint reflection data that the
average velocity between the seafloor and the bottom-simulating reflector
(BSR) is <1600 m/s throughout the region and is lowest near the
summit, where the amount of hydrate is greatest. This result supports
the conclusions that free gas and hydrate coexist beneath the summit
and that the average amount of gas hydrate present elsewhere is low.
The data also indicate that low-velocity zones (LVZs) resulting from free
gas beneath the BSR must be thin and stratigraphically controlled. The
only LVZ resolvable from traveltime analysis of the VSP data is associated
with Horizon A, which has been interpreted to be the primary conduit
transporting free gas to vents at the summit of South Hydrate
Ridge. Thin LVZs associated with Horizons B and B', however, are indicated
by sonic logs as well as by strong negative polarity reflections in
the multichannel seismic data. This limited distribution of sub-BSR free
gas contrasts with previous results at North Hydrate Ridge (Leg 146)
and Blake Ridge (Leg 164), which indicate the presence of free gas zones
several hundred meters thick that result in distinct LVZs in the VSP data
from those earlier ODP legs
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In-Situ Sampling and Characterization of Naturally Occuring Marine Methane Hydrate Using the D/V JOIDES Resolution
The primary accomplishments of the JOI Cooperative Agreement with DOE/NETL in this quarter were that: (1) Leg 204 scientific party members presented preliminary results and operational outcomes of ODP Leg 204 at the American Geophysical Union Fall meeting, which was held in San Francisco, CA; and, (2) a report was prepared by Dr. Gilles Guerin and David Goldberg from Lamont-Doherty Earth Observatory of Columbia University on their postcruise evaluation of the data, tools and measurement systems that were used for vertical seismic profiling (VSP) experiments during ODP Leg 204. The VSP report is provided herein. Intermediate in scale and resolution between the borehole data and the 3-D seismic surveys, the Vertical Seismic Profiles (VSP) carried during Leg 204 were aimed at defining the gas hydrate distribution on hydrate ridge, and refining the signature of gas hydrate in the seismic data. VSP surveys were attempted at five sites, following completion of the conventional logging operations. Bad hole conditions and operational difficulties did not allow to record any data in hole 1245E, but vertical and constant offset VSP were successful in holes 1244E, 1247B and 1250F, and walk-away VSP were successfully completed in holes 1244E, 1250F and 1251H. Three different tools were used for these surveys. The vertical VSP provided the opportunity to calculate interval velocity that could be compared and validated with the sonic logs in the same wells. The interval velocity profiles in Holes 1244E and 1247B are in very good agreement with the sonic logs. Information about the Leg 204 presentations at the AGU meeting are included in a separate Topical Report, which has been provided to DOE/NETL in addition to this Quarterly Report. Work continued on analyzing data collected during ODP Leg 204 and preparing reports on the outcomes of Phase 1 projects as well as developing plans for Phase 2
Prevalence, risk factors, and impact on outcome of cytomegalovirus replication in serum of Cambodian HIV-infected patients (2004-2007)
BACKGROUND: In developing countries, the study of cytomegalovirus (CMV) coinfection in HIV-infected patients remains neglected. Quantitative CMV polymerase chain reaction (PCR) is the gold standard diagnostic tool for analyzing serum CMV replication and for predicting CMV disease. We estimated the prevalence of replicating CMV in sera of newly diagnosed HIV-infected Cambodian patients and examined its impact on mortality. METHODS: This cohort study was based on 2 highly active antiretroviral therapy treatment programs in Cambodia between 2004 and 2007. Quantitative CMV PCR was performed on baseline serum samples of 377 HIV-infected patients. RESULTS: The prevalence of serum CMV DNA was 55.2% (150 of 272) in patients with CD4 count <100/mm. In multivariate analysis, hemoglobin <9 g/dL, CD4 count <100/mm, and Karnofsky index <50 were independently associated with positive serum CMV DNA at baseline. During a 3-year follow-up period, CMV viral load >or=3.1 log10 copies per milliliter was significantly associated with death independently of CD4 count, other opportunistic infections, and highly active antiretroviral therapy. CONCLUSIONS: As in industrialized countries, serum CMV replication is highly prevalent among HIV-infected Cambodian patients and is associated with increased mortality. This underscores the importance of diagnostic CMV infection by PCR in sera of HIV-infected patients with CD4 count <100/mm and treating this opportunistic infection to reduce its associated mortality
PALĂORIVAGES, DUNES CĂTIĂRES ET OCCUPATIONS HUMAINES Ă LâEMBOUCHURE DE LâOUED TAMRI, MAROC ATLANTIQUE, AU PLĂISTOCĂNE SUPĂRIEUR (SIM 5)
A lâembouchure de lâoued Tamri, rive gauche, un palĂ©orivage de faciĂšs marin et fluvio-marin (unitĂ© U1) culmine aux environs de + 6m a.s.l. Une coquille marine de Patella sp. prĂ©levĂ©e dans cette unitĂ© U1 (faciĂšs marin) a Ă©tĂ© datĂ©e 100,02 ± 1,662 ka et 101,188 ± 1,339 ka par la mĂ©thode U/Th (SIM 5.3). La dune surincombante (sĂ©rie Sx) a Ă©tĂ© datĂ©e par OSL 84 ± 4 ka (SIM 5.1). A Tighrine Imksawne, Ă 200 m au Sud de lâembouchure, ce palĂ©orivage est surmontĂ© dâune sĂ©quence de dĂ©pĂŽts dunaires et colluviaux de plus de 20 m dâĂ©paisseur. Ces derniers renferment plusieurs palĂ©osols rubĂ©fiĂ©s interstratifiĂ©s et des encroĂ»tements, tĂ©moins de pĂ©riodes humides et de ruissellements, qui permettent de distinguer trois unitĂ©s principales (unitĂ©s U2, U3, U4) :(U2), unitĂ© dâaccumulation interdunaire infĂ©rieure, oĂč dominent les faciĂšs dĂ©tritiques continentaux de colluvionnement/ruissellement, avec de nombreux HĂ©licidĂ©s et de rares tĂ©moins dâoutillage lithique. (U3), unitĂ© dâaccumulation Ă©olienne moyenne, Ă sĂ©ries dunaires encroĂ»tĂ©es, oĂč la sĂ©rie (S5) a Ă©tĂ© datĂ©e par OSL 92 ± 6 ka (SIM 5.3 ou SIM 5.2), et oĂč le palĂ©osol rubĂ©fiĂ© (S6) a fourni une industrie Ă proto-hachereaux. (U4), unitĂ© dâaccumulation Ă©olienne supĂ©rieure Ă sĂ©ries friables, sĂ©parĂ©e de la prĂ©cĂ©dente par une palĂ©o-surface encroĂ»tĂ©e (S6/S7) Ă industrie probablement Ă©pipalĂ©olithique, et oĂč des coquilles dâĆufs dâAutruche de la sĂ©rie (S8) sont datĂ©es par radiocarbone Ă plus de 30 ka. BPLes analyses gĂ©omorphologiques, sĂ©dimentologiques et pĂ©trographiques aboutissent Ă un modĂšle sĂ©dimentaire dâaccumulation de pied de falaise morte qui permet de rĂ©pondre aux contradictions apparentes entre la position de lâindustrie lithique et des datations.A lâembouchure de lâoued Tamri, rive gauche, un palĂ©orivage de faciĂšs marin et fluvio-marin (unitĂ© U1) culmine aux environs de + 6m a.s.l. Une coquille marine de Patella sp. prĂ©levĂ©e dans cette unitĂ© U1 (faciĂšs marin) a Ă©tĂ© datĂ©e 100,02 ± 1,662 ka et 101,188 ± 1,339 ka par la mĂ©thode U/Th (SIM 5.3). La dune surincombante (sĂ©rie Sx) a Ă©tĂ© datĂ©e par OSL 84 ± 4 ka (SIM 5.1). A Tighrine Imksawne, Ă 200 m au Sud de lâembouchure, ce palĂ©orivage est surmontĂ© dâune sĂ©quence de dĂ©pĂŽts dunaires et colluviaux de plus de 20 m dâĂ©paisseur. Ces derniers renferment plusieurs palĂ©osols rubĂ©fiĂ©s interstratifiĂ©s et des encroĂ»tements, tĂ©moins de pĂ©riodes humides et de ruissellements, qui permettent de distinguer trois unitĂ©s principales (unitĂ©s U2, U3, U4) :(U2), unitĂ© dâaccumulation interdunaire infĂ©rieure, oĂč dominent les faciĂšs dĂ©tritiques continentaux de colluvionnement/ruissellement, avec de nombreux HĂ©licidĂ©s et de rares tĂ©moins dâoutillage lithique. (U3), unitĂ© dâaccumulation Ă©olienne moyenne, Ă sĂ©ries dunaires encroĂ»tĂ©es, oĂč la sĂ©rie (S5) a Ă©tĂ© datĂ©e par OSL 92 ± 6 ka (SIM 5.3 ou SIM 5.2), et oĂč le palĂ©osol rubĂ©fiĂ© (S6) a fourni une industrie Ă proto-hachereaux. (U4), unitĂ© dâaccumulation Ă©olienne supĂ©rieure Ă sĂ©ries friables, sĂ©parĂ©e de la prĂ©cĂ©dente par une palĂ©o-surface encroĂ»tĂ©e (S6/S7) Ă industrie probablement Ă©pipalĂ©olithique, et oĂč des coquilles dâĆufs dâAutruche de la sĂ©rie (S8) sont datĂ©es par radiocarbone Ă plus de 30 ka. BPLes analyses gĂ©omorphologiques, sĂ©dimentologiques et pĂ©trographiques aboutissent Ă un modĂšle sĂ©dimentaire dâaccumulation de pied de falaise morte qui permet de rĂ©pondre aux contradictions apparentes entre la position de lâindustrie lithique et des datations
Stimulation of MMP-11 (stromelysin-3) expression in mouse fibroblasts by cytokines, collagen and co-culture with human breast cancer cell lines
BACKGROUND: Matrix metalloproteinases (MMPs) are central to degradation of the extracellular matrix and basement membrane during both normal and carcinogenic tissue remodeling. MT1-MMP (MMP-14) and stromelysin-3 (MMP-11) are two members of the MMP family of proteolytic enzymes that have been specifically implicated in breast cancer progression. Expressed in stromal fibroblasts adjacent to epithelial tumour cells, the mechanism of MT1-MMP and MMP-11 induction remains unknown. METHODS: To investigate possible mechanisms of induction, we examined the effects of a number of plausible regulatory agents and treatments that may physiologically influence MMP expression during tumour progression. Thus NIH3T3 and primary mouse embryonic fibroblasts (MEFs) were: a) treated with the cytokines IL-1ÎČ, IL-2, IL-6, IL-8 and TGF-ÎČ for 3, 6, 12, 24, and 48 hours; b) grown on collagens I, IV and V; c) treated with fibronectin, con-A and matrigel; and d) co-cultured with a range of HBC (human breast cancer) cell lines of varied invasive and metastatic potential. RESULTS: Competitive quantitative RT-PCR indicated that MMP-11 expression was stimulated to a level greater than 100%, by 48 hour treatments of IL-1ÎČ, IL-2, TGF-ÎČ, fibronectin and collagen V. No other substantial changes in expression of MMP-11 or MT1-MMP in either tested fibroblast culture, under any treatment conditions, were observed. CONCLUSION: We have demonstrated significant MMP-11 stimulation in mouse fibroblasts using cytokines, matrix constituents and HBC cell lines, and also some inhibition of MT1-MMP. Our data suggest that the regulation of these genes in the complex stromal-epithelial interactions that occur in human breast carcinoma, is influenced by several mechanisms
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