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881.
The risk of both severe and frequent injury associated with active pursuits in mountain areas is acknowledged. This phenomenon is all the most relevant to investigate in France that there is a growing enthusiasm for outdoor sports and recreation. This paper focuses on the social-demographic and sporting profiles of accident victims. Our intent is to better understand who is specifically at risk, while practicing mountain recreation, in the French mountains. Such identification doubtlessly constitutes an important asset in order to enhance prevention. Three critical activities are notably tackled, among some others: hiking, a widespread activity that exposes many practitioners to hazardous settings; mountaineering and ski touring, supposedly entailing the most severe injuries. In order to align the information collected, then provide estimations based on the reasoned crossing of these secondary data, we consulted and summarised all the databases that we knew of on the French territory: rescue team intervention reports, aggregated statistics from the sports ministry, sporting federation accident declarations, avalanche experts statistics, mountain guides union accident/incident reports, healthcare facilities admissions, etc. Only the sources considered to be the most reliable and representative were used, owing to the number of cases processed, the exhaustive nature of data collection, or the level of information detail available. Our method also included consultation of all the parties playing an active role in prevention, training and mountain rescue, thus ensuring a participative, co-constructive approach to the study with the people that have the best knowledge of victims’ profiles. Around fifty such parties were interviewed on the methods implemented, the benefits and limits of current data, and the main expectations in terms of accidentology progress, thus further enhancing the credibility of the study proposed in this paper. Our results show that the parent population profiles (in terms of age, gender, place of residence, etc.), weighted by the level of exposure (frequency of participation, level of engagement, etc.) appears to have an impact on the accident victim profiles. There is certainly a very marked gender bias and a serious age impact to be taken into account, as well as the influence of the level of experience, which counter certain preconceived ideas and which, at the very least, go against instinct. However, aside from a probable over-exposure of experienced or expert participants, much remains to be explained concerning the accident mechanisms and circumstances involved. At this stage, we regret the analytic deficiencies induced by a lack of knowledge concerning the parent populations in many cases, which makes interpretation difficult. 相似文献
882.
Dale P. Cruikshank Eric Wegryn R.H. Brown B.J. Buratti T.B. McCord Y.J. Pendleton G. Filacchione P. Cerroni R. Jaumann K.H. Baines G. Bellucci Y. Langevin D.L. Matson P. Drossart 《Icarus》2008,193(2):334-343
Material of low geometric albedo (pV?0.1) is found on many objects in the outer Solar System, but its distribution in the saturnian satellite system is of special interest because of its juxtaposition with high-albedo ice. In the absence of clear, diagnostic spectral features, the composition of this low-albedo (or “dark”) material is generally inferred to be carbon-rich, but the form(s) of the carbon is unknown. Near-infrared spectra of the low-albedo hemisphere of Saturn's satellite Iapetus were obtained with the Visible-Infrared Mapping Spectrometer (VIMS) on the Cassini spacecraft at the fly-by of that satellite of 31 December 2004, yielding a maximum spatial resolution on the satellite's surface of ∼65 km. The spectral region 3-3.6 μm reveals a broad absorption band, centered at 3.29 μm, and concentrated in a region comprising about 15% of the low-albedo surface area. This is identified as the CH stretching mode vibration in polycyclic aromatic hydrocarbon (PAH) molecules. Two weaker bands attributed to CH2 stretching modes in aliphatic hydrocarbons are found in association with the aromatic band. The bands most likely arise from aromatic and aliphatic units in complex macromolecular carbonaceous material with a kerogen- or coal-like structure, similar to that in carbonaceous meteorites. VIMS spectra of Phoebe, encountered by Cassini on 11 June 2004, also show the aromatic hydrocarbon band, although somewhat weaker than on Iapetus. The origin of the PAH molecular material on these two satellites is unknown, but PAHs are found in carbonaceous meteorites, cometary dust particles, circumstellar dust, and interstellar dust. 相似文献
883.
Eric R. Priest 《Astrophysics and Space Science》1996,237(1-2):49-73
The theory of magnetic reconnection has advanced substantially over the past few years. There now exists a new generation
of fast two-dimensional models known as almost-uniform reconnection and nonuniform reconnection, depending on the boundary
conditions. Also, we are beginning to explore the uncharted region of three-dimensional reconnection, where regimes of “spine
reconnection” and “fan reconnection” have been discovered. Furthermore, part of the coronal heating problem appears to have
been solved with recent observational support for the Converging Flux Model in which heating is produced by coronal reconnection
driven by footpoint motions. 相似文献
884.
Eric Buffetaut 《地学学报》1989,1(1):69-74
The Late Cretaceous (mainly Campanian and Maastrichtian) non-marine vertebrate faunas of Europe contain archosaurian reptiles which belong to groups otherwise known mainly or only from the southern ('Gondwanan') continents. They include titanosaurid sauropods, abelisaurid theropods, and trematochampsid crocodilians. The occurrence of these forms together with others of 'Asiamerican' affinities gives the Late Cretaceous vertebrate faunas of Europe a peculiar composition, which makes them clearly different from the well-known faunas from western North America and Central Asia. The Gondwanan dinosaurs and crocodilians from Europe provide evidence of faunal interchange across the Tethys Sea during the Cretaceous, possibly via the Alboran plate, or the Apulian plate, which may have functioned as 'stepping-stones', especially during periods of low sea level. 相似文献
885.
886.
Wang-Hong Yang R. James Kirkpatrick Norma Vergo John McHone Tryggvi I. Emilsson Eric Oldfield 《Meteoritics & planetary science》1986,21(1):117-124
High-resolution solid-state silicon-29 nuclear magnetic resonance spectroscopy using “magic-angle” sample-spinning can readily detect the presence of the high pressure silica polymorphs coesite and stishovite in whole-rock samples from a Meteor Crater, Arizona, impact sample, and yields accurate coesite/stishovite ratios. Such determinations are being carried out by partially suppressing (saturating) intense quartz signals (which have long spin-lattice relaxation times) by means of short experimental recycle-times. This method enhances the signal-to-noise ratios of coesite and stishovite (which have relatively short spin-lattice relaxation times). For the sample examined, the coesite/stishovite ratio is about 27. 相似文献
887.
888.
Eric A. Crecelius 《Marine Chemistry》1980,8(3):245-250
The elemental solubilities of three coal fly ash samples and two coastal marine-aerosol samples in seawater are different. The coal fly ash samples were collected from the electrostatic precipitators on coal-fired power plants. The air particulates were collected by a high-volume air sampler located near the Washington coast. Samples were neutron-activated then contacted with seawater for several hours. The elements that were partially solubilized from both fly ash and aerosols included As, Sb, Se, Br and Cr. Zinc and Co were more soluble in aerosols then fly ash. 相似文献
889.
Herbert W. Schnopper Eric Silver Stephen Murray Suzanne Romaine Simon Bandler Christine Jones William Forman Norman Madden Jeffery Beeman Eugene Haller Finn Christensen Niels Westergaard Juan Fabregat Victor Reglero Alvaro Gimenez Noah Brosch Elia Liebowitz Hagai Netzer Marco Barbera Alfonso Collura Salvatore Sciortino 《Astrophysics and Space Science》2001,276(1):49-65
The X-Ray Spectroscopic Explorer (XRASE) has a unique combination of features that will make it possible to address many of NASA's scientific goals. These include how galaxy clusters form, the physics and chemistry of the ISM, the heating of stellar coronae, the amount and content of intergalactic baryonic matter, the mass of black holes and the formation of disks and jets in AGN and galactic binaries. XRASE has a thin foil, multilayered telescope with a large collecting area up to 10 keV, especially in the Fe K region (1100 cm2). Its microcalorimeter array combines high energy resolution (7 eV at 6 keV) and efficiency with a field-of-view of 26 arcmin2 . A deep orbit allows for long, continuous observations. Monitoring instruments in the optical (WOM-X), UV (TAUVEX) and hard X-RAY (GRAM) bands will offer exceptional opportunities to make simultaneous multi-wavelength observations. 相似文献
890.
Anthony?C.?WithersEmail author Eric?J.?Essene Youxue?Zhang 《Contributions to Mineralogy and Petrology》2003,145(2):199-204
The transition between rutile and α-PbO2 structured TiO2 (TiO2II) has been investigated at 700–1,200 °C and 4.2–9.6 GPa. Hydrothermal phase equilibrium experiments were performed in the multi-anvil apparatus to bracket the phase boundary at 700, 1,000, and 1,200 °C. The equilibrium phase boundary is described by the equation: P (GPa)=1.29+0.0065 T ( °C). In addition, growth of TiO2II was observed in experiments at 500 and 600 °C, although growth of rutile was too slow to bracket unambiguously the equilibrium boundary at these temperatures. Water was not detected in either rutile or TiO2II, and dry synthesis experiments at 1,200 °C were consistent with the phase boundary determined in the fluid-bearing experiments, suggesting that the equilibrium is unaffected by the presence of water. Our bracket of the phase boundary at 700 °C is consistent with the reversed, dry experiments of Akaogi et al. (1992) and the reversals of Olsen et al. (1999). The new data suggest that the phase boundary is linear, in agreement with Akaogi et al. (1992), but in striking contrast to the phase diagram inferred by Olsen et al. (1999). The natural occurrence of TiO2II requires formation pressures considerably higher than the graphite–diamond phase boundary. 相似文献