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71.
Jean René Bertrand 《GeoJournal》2006,67(4):295-306
In France the distinction between the secular and religious domains is the result of a slow evolutionary process of secularization
over a period of two centuries. A key element was the law of separation between churches and State in 1905. Secularization
also produced a pluralistic socio-cultural system, which permits an increase in religious supply, issued from outside or inside
existent churches. The religious landscape became complex due to the growth of certain groups. Nowadays, efforts to regulate
Muslim communities are leading towards a new tendency of state control of religious activities in two fields, namely places
of worship and school activities. Religious plurality is recognized by the State in the name of the freedom of beliefs. Private
organizations are used for the public practice of religion and easily obtain places of worship. However, this has necessitated
a large number of regional or local arrangements. In the name of the freedom of thought, the school system of the Republic
is ensured by public schools, or by Catholic or Jewish schools, subject to strict public control. In this matter, there is
only minimal tolerance of other denominations.
相似文献
Jean René BertrandEmail: |
72.
European Venus Explorer (EVE): an in-situ mission to Venus 总被引:1,自引:0,他引:1
E. Chassefière O. Korablev T. Imamura K. H. Baines C. F. Wilson D. V. Titov K. L. Aplin T. Balint J. E. Blamont C. G. Cochrane Cs. Ferencz F. Ferri M. Gerasimov J. J. Leitner J. Lopez-Moreno B. Marty M. Martynov S. V. Pogrebenko A. Rodin J. A. Whiteway L. V. Zasova J. Michaud R. Bertrand J.-M. Charbonnier D. Carbonne P. Raizonville 《Experimental Astronomy》2009,23(3):741-760
The European Venus Explorer (EVE) mission was proposed to the European Space Agency in 2007, as an M-class mission under the
Cosmic Vision Programme. Although it has not been chosen in the 2007 selection round for programmatic reasons, the EVE mission
may serve as a useful reference point for future missions, so it is described here. It consists of one balloon platform floating
at an altitude of 50–60 km, one descent probe provided by Russia, and an orbiter with a polar orbit which will relay data
from the balloon and descent probe, and perform science observations. The balloon type preferred for scientific goals is one
which oscillates in altitude through the cloud deck. To achieve this flight profile, the balloon envelope contains a phase
change fluid, which results in a flight profile which oscillates in height. The nominal balloon lifetime is 7 days—enough
for one full circumnavigation of the planet. The descent probe’s fall through the atmosphere takes 60 min, followed by 30 min
of operation on the surface. The key measurement objectives of EVE are: (1) in situ measurement from the balloon of noble
gas abundances and stable isotope ratios, to study the record of the evolution of Venus; (2) in situ balloon-borne measurement
of cloud particle and gas composition, and their spatial variation, to understand the complex cloud-level chemistry; (3) in
situ measurements of environmental parameters and winds (from tracking of the balloon) for one rotation around the planet,
to understand atmospheric dynamics and radiative balance in this crucial region. The portfolio of key measurements is complemented
by the Russian descent probe, which enables the investigation of the deep atmosphere and surface. 相似文献
73.
Rosanna Sordo Antonella Vallenari Rosaria Tantalo France Allard Ronny Blomme Jean-Claud Bouret Ines Brott Yves Fremat Christophe Martayan Yassine Damerdji Bengt Edvardsson Eric Josselin Bertrand Plez Oleg Kochukhov Mary Kontizas Ulisse Munari Tenay Saguner Jean Zorec Andreas Schweitzer Paraskevi Tsalmantza 《Astrophysics and Space Science》2010,328(1-2):331-335
ESA’s Gaia mission will collect low resolution spectroscopy in the optical range for ~109 objects. Complete and up-to-date libraries of synthetic stellar spectra are needed to built algorithms aimed to automatically derive the classification and the parametrization of this huge amount of data. In addition, libraries of stellar spectra are one of the main ingredients of stellar population synthesis models, aiming to derive the properties of unresolved stellar populations from their integrated light. We present (a) the newly computed libraries of synthetic spectra built by the Gaia community, covering the whole optical range (300–1100 nm) at medium-high resolution of (0.3 nm) for stars spanning the most different types, from M to O, from A-peculiar to Emission lines to White Dwarfs, and (b) the implementation of those libraries in our SSP code (Tantalo in The Initial Mass Function 50 Years Later, 327:235 2005), exploring different stellar evolution models. 相似文献
74.
Leila Djadia Djamel Machane Jean-Luc Chatelain Abdesslam Abtout Rabah Bensalem Mehdi Amine Guemache Bertrand Guillier Amar Boudella El-Hadi Oubaiche 《Environmental Earth Sciences》2010,59(5):1149-1158
Results from geophysical investigations (electrical resistivity, electromagnetic mapping and seismic refraction) on an excavated
cell of the Ouled Fayet (Algiers, Algeria) pilot landfill indicated the presence of an underground runoff and permeable soil
underneath the cell. These results contradict those obtained by a feasibility study, based, however, only on the analysis
of seventy-six 10-m drilling cores. The 1D boreholes information has been proven to be insufficient and to give biased results.
The presence of water at depth is evidenced by lower resistivity, high conductivity anomalies and increase of P-wave velocity.
Thus, to the contrary of what is claimed in the feasibility study, a threat of leachate pollution is real. This study shows
that landfill construction studies cannot give trustful results without geophysical investigations. More specifically, in
Algeria, it is imperative to elaborate a landfill construction code, which should include mandatory geophysical prospecting
and deeper drilling cores. 相似文献
75.
Where do fishmeal and fish oil products come from? An analysis of the conversion ratios in the global fishmeal industry 总被引:1,自引:0,他引:1
As a result of the stagnation of commercial fishery landings, aquaculture activities are expected to increase over the next decades to match the growing demand for marine protein. Overall, it is expected that the aquaculture sector could reduce some of the fishing pressure applied to wild stocks. However, this development is likely to be limited by the availability of key aquaculture inputs, specifically fishmeal and fish oil products (FMFOP). Aquaculture provided 60 % (fish meal) and 80 % (fish oil) of the world total consumption of these products in 2007. FMFOP are generally derived from small pelagic fish species, but can also be derived from other sources. Identifying the origin of FMFOP is crucial to understanding the effects of this new pressure on marine social-ecological systems. Two factors are of particular importance in the reduction sector transforming wild fish into fishmeal or fish oil: the two “conversion ratios” (i.e. the ratio between the quantity of wild fish harvested and the resulting quantity of FMFOP, and the ratio between the quantity of FMFOP and aquaculture production), and the type of raw material used by the reduction sector. Based on trade and production databases from FAO and the International Fishmeal and Fish oil Organisation (IFFO), this paper proposes an approach to identify the origin of FMFOP. It shows that whereas different countries use different pelagic resources to produce FMFOP, other countries use non-pelagic sources, and some countries use pelagic resources for human consumption. 相似文献
76.
Schooling behaviour and environmental forcing in relation to anchoveta distribution: An analysis across multiple spatial scales 总被引:7,自引:4,他引:3
Arnaud Bertrand Franois Gerlotto Sophie Bertrand Mariano Gutirrez Luis Alza Andres Chipollini Erich Díaz Pepe Espinoza Jesús Ledesma Roberto Quesqun Salvador Peraltilla Francisco Chavez 《Progress in Oceanography》2008,79(2-4):264
The Peruvian anchovy or anchoveta (Engraulis ringens) supports the highest worldwide fishery landings and varies in space and time over many scales. Here we present the first comprehensive sub-mesocale study of anchoveta distribution in relation to the environment. During November 2004, we conducted a behavioural ecology survey off central Peru and used a series of observational and sampling tools including SST and CO2 sensors, Niskin bottles, CTD probes, zooplankton sampling, stomach content analysis, echo-sounder, multibeam sonar, and bird observations. The sub-mesoscale survey areas were chosen from mesoscale acoustic surveys. A routine coast-wide (2000 km) acoustic survey performed just after the sub-mesoscale surveys, provided information at an even larger population scale. The availability of nearly concurrent sub-mesoscale, mesoscale and coast-wide information on anchoveta distribution allowed for a unique multi-scale synthesis. At the sub-mesoscale (100s m to km) physical processes (internal waves and frontogenesis) concentrated plankton into patches and determined anchoveta spatial distribution. At the mesoscale (10s km) location relative to the zone of active upwelling (and age of the upwelled water) and the depth of the oxycline had strong impacts on the anchoveta. Finally, over 100s km the size of the productive area, as defined by the upwelled cold coastal waters, was the determining factor. We propose a conceptual view of the relative importance of social behaviour and environmental (biotic and abiotic) processes on the spatial distribution of anchoveta. Our ecological space has two y-axis; one based on self-organization (social behaviour), and the other based on the environmental processes. At scales from the individual (10s cm), to the nucleus (m), social behaviour (e.g. the need to school) drives spatial organization. At scales larger than the school, environmental forces are the main driver of fish distribution. The conceptual ecosystem models presented in this paper may provide the final links needed to develop accurate forecasts of the spatial distribution of anchoveta over multiple scales. 相似文献
77.
78.
D.Z. Piper H.H. Veeh W.G. Bertrand R.L. Chase 《Earth and Planetary Science Letters》1975,26(1):114-120
An iron-rich deposit dredged from the upper flank of Dellwood Seamount in the Northeast Pacific has been analyzed for major and trace elements, rare-earth contents and uranium isotopic composition. In terms of mineralogy and overall chemical composition, the deposit resembles other iron-rich deposits variously attributed to volcanic hydrothermal activity. Both the relative concentrations of the rare-earth elements and the isotopic composition of uranium rule out seawater as the sole source of elements in this deposit. The rare-earth element pattern indicates that these elements were derived from the underlying basalt. The234U/238U ratio is significantly higher than in seawater and can best be explained by preferential leaching of234U generated by decay from its parent238U in the underlying rock and subsequent redeposition of the excess234U together with the Fe and minor metals. These data are consistent with a model for the origin of submarine metal-rich solutions involving mobilization of elements from the interior of slowly cooling basalts by circulating seawater. 相似文献
79.
K. Hughen J. Southon S. Lehman C. Bertrand J. Turnbull 《Quaternary Science Reviews》2006,25(23-24):3216
An expanded Cariaco Basin 14C chronology is tied to 230Th-dated Hulu Cave speleothem records in order to provide detailed marine-based 14C calibration for the past 50,000 years. The revised, high-resolution Cariaco 14C calibration record agrees well with data from 230Th-dated fossil corals back to 33 ka, with continued agreement despite increased scatter back to 50 ka, suggesting that the record provides accurate calibration back to the limits of radiocarbon dating. The calibration data document highly elevated Δ14C during the Glacial period. Carbon cycle box model simulations show that the majority of observed Δ14C change can be explained by increased 14C production. However, from 45 to 15 ka, Δ14C remains anomalously high, indicating that the distribution of radiocarbon between surface and deep ocean reservoirs was different than it is today. Additional observations of the magnitude, spatial extent and timing of deep ocean Δ14C shifts are critical for a complete understanding of observed Glacial Δ14C variability. 相似文献
80.
Petrology and U/Pb geochronology of the Telohat migmatites,Aleksod, Central Hoggar,Algeria 总被引:6,自引:0,他引:6
Pierre Barbey Jean-Michel Bertrand Serge Angoua Danielle Dautel 《Contributions to Mineralogy and Petrology》1989,101(2):207-219
The Aleksod region is composed of metasedimentary rocks and large areas of biotite and hornblende-bearing migmatites. Anatexis
associated with the main deformation stages, occurred under high pressure and temperature conditions estimated at 13±2 Kbar
and 750±50° C. The bulk mineralogical composition of the Telohat migmatites shows that their protolith was granodioritic.
Internal structures of zircons and U-Pb data suggest a polyphased evolution, with a 2131±12 Ma age for the protolith and a
609±17 Ma age for the Pan-African tectono-metamorphic evolution, thus precluding any Kibaran event in the Aleksod area. Leucosomes
are richer in Sr and display lower Rb, Zr, Nb, Y, Th, U and REE contents than melanosomes wherein accessory phases are stored.
Eu contents are also lower in the leucosomes but in lesser proportion than the other rare earth's, leading to a significant
positive anomaly. Petrogenetic modelling accounting for accessory mineral phases clearly shows that the trace element contents
of leucosomes and melanosomes follow a distribution law consistent neither with equilibrium nor fractional melting. Their
trace element patterns are best explained by the model of disequilibrium melting, with mixing of a few residual phases. The
present results and previous Sr isotopic data as well raise the question of disequilibrium melting in anatexis of crustal
material
CRPG Contribution no 782 相似文献