13 research outputs found
Near-infrared identification of the counterpart to X1908+075: a new OB-supergiant X-ray binary
We report the near-infrared (IR) identification of the likely counterpart to
X1908+075, a highly-absorbed Galactic X-ray source recently suspected to belong
to the rare class of OB supergiant-neutron star binary systems. Our JHKs-band
imaging of the field reveals the existence within the X-ray error boxes of a
near-IR source consistent with an early-type star lying at d=7 kpc and
suffering A(V)=16 mag of extinction, the latter value being in good agreement
with the hydrogen column density derived from a modelling of the X-ray
spectrum. Our follow-up, near-IR spectroscopic observations confirm the nature
of this candidate and lead to a late O-type supergiant classification, thereby
supporting the identification of a new Galactic OB-supergiant X-ray binary.Comment: Accepted for publication in MNRAS, 7 pages, 3 figure
X1908+075: A Late O-Type Supergiant with a Neutron Star Companion
X1908 + 075 is a highly-absorbed Galactic X-ray source likely made up of a pulsar accreting wind material from a massive companion. We have used near-IR photometric data complemented by follow-up spectroscopy to identify the likely counterpart to this X-ray source and to assign a spectral type O7.5 9.5 If to the primary. Further details can be found in Morel and Grosdidier (2005)
LE PHENOMENE WOLF-RAYET AU SEIN DES ETOILES CHAUDES DE POPULATIONS I ET II (HISTOIRE DES VENTS STELLAIRES ET IMPACT SUR LA STRUCTURE NEBULAIRE CIRCUMSTELLAIRE)
STRASBOURG-Sc. et Techniques (674822102) / SudocSudocFranceF
HF Bistatic Ocean Doppler Spectra: Simulation Versus Experimentation
We simulate the Doppler spectra that can be obtained under experimental conditions from bistatic high-frequency oceanic radar. For this, we combine the bistatic second-order theory with the characteristics of the full radar system, such as antenna patterns, range attenuation, and postprocessing of the received signal. Because of the sharp variation of the bistatic geometry at short range, we show that it is crucial to take these effects into account for the correct interpretation of the first-order Bragg peaks. The second-order spectrum is more robust to the system characteristics but can under some conditions also suffer from its artifacts, especially in the vicinity of the secondary peaks. A comparison is made with experimental spectra acquired recently with a Wellen radar system on the Mediterranean coast. The Wave Watch III model is used to simulate directional wave height spectra after a preliminary validation with in situ buoy measurements. Experimental and simulated Doppler spectra agree generally well, except in the case where the directional wave spectrum has little energy in the line of sight of the radar
On the Influence of Ultrasonic Surface Mechanical Attrition Treatment (SMAT) on the Fatigue Behavior of the 304L Austenitic Stainless Steel
International audienc
Relationships between lung adenocarcinoma and gender, age, smoking and occupational risk factors: A case-case study.
International audienceBACKGROUND: The hypothesis that some risk factors for lung cancer may have more specific associations with particular histologic types remains controversial. The aim of this study was to investigate possible associations between adenocarcinoma and gender, age, smoking characteristics and selected occupational carcinogens in relation to other histologic types. METHODS: This study included all histologically confirmed lung cancer cases diagnosed consecutively in two French University hospitals from 1997 to 2006. All medical data were obtained by face-to-face patient interviews. Occupational carcinogen exposures of each patient were assessed by an industrial hygienist. Relationships between risk factors and adenocarcinoma were analyzed by case-case comparisons using unconditional logistic regressions (ULRs). RESULTS: A total of 1493 subjects were enrolled in this study, comprising 1303 men (87.3%), 67 nonsmokers (4.5%) and 489 adenocarcinomas (32.7%). Using ULR, no associations were observed between adenocarcinoma and age, gender or smoking characteristics except for a negative relationship with smoking duration (p<0.0001). Significant associations were observed between ADC and exposure to welding fumes and silica in the whole population and with polycyclic aromatic hydrocarbons in ever smokers. CONCLUSION: This study demonstrated that some risk factors, such as duration of smoking and certain occupational exposures but not gender or age, have a more important influence on the incidence of lung ADC than on other histologic types. As the distribution of histologic types may reflect underlying biological mechanisms, these findings also suggest that lung carcinogenesis pathways should be studied in relation to smoking duration and other lung cancer risk factors
Characteristics of never smoker lung cancer including environmental and occupational risk factors.
International audienceINTRODUCTION: Clinical characteristics and risk factors of nonsmoker patients with lung cancer are still debated. AIM AND METHODS: The aim of this work is to describe the characteristics of never smoker patients with lung cancer, focusing on occupational and environmental exposures, Data collected were: age, gender, histological types, methods of diagnosis, TNM staging, smoking, and occupational data. Statistical analysis included descriptive analyses, Pearson's chi-square or nonparametric tests, and logistic regressions. RESULTS: All lung cancers diagnosed between January 1, 1997 and December 31, 2006, representing 1493 cases were included. Lung adenocarcinoma (ADC) [Odds Ratio (OR)=2.5 (1.5-4.3), p<0.0001] as well as clinical stage I cases at diagnosis [OR=2.4 (1.3-4.3)] were most frequent in nonsmokers relative to ever smokers. Comparison of clinical features among male and female nonsmoker patients did not reveal significant differences. Conversely, strong differences appeared when comparing environmental tobacco smoke (ETS) and occupational exposures in nonsmoker women vs men: ETS exposure (78.6% nonsmoker women vs 21.4% nonsmoker men, p<0.0001), occupational exposure (9.4% vs 48.6%, p<0.0005). Noteworthy, a sizeable number of nonsmoker male (40.0%), and nonsmoker female (31.2%) patients had no known exposure to major lung carcinogens. CONCLUSIONS: Main risk factors (ETS and occupational exposure) may only explain some cases