Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
ISSN: 0003-4975

hal-01563338
http://hal.univ-brest.fr/hal-01563338
DOI : 10.1016/j.athoracsur.2016.03.093
PUBMED : 27262916

Éditeur(s) : HAL CCSD American Geophysical Union (AGU)
Résumé : International audience
Apatite fission track analysis (AFTA) data are used to bring new light on the long-term and recent history of the Baikal rift region (Siberia). We describe the evolution of the topography along a NW-SE profile from the Siberian platform to the Barguzin range across the Baikal-southern Patom range and the northern termination of Lake Baikal. Our results show that the Baikal-Patom range started to form in the Early Carboniferous and was reactivated in Middle Jurassic-Lower Cretaceous times during the orogenic collapse of the Mongol-Okhotsk belt. Samples located in the Siberian platform recorded a continuous sedimentation up to the early Carboniferous but remain unaffected by later tectonic episodes. The Barguzin basin probably started to form as early as Late Cretaceous, suggesting a continuum of deformation between the postorogenic collapse and the opening of the Baikal Rift System (BRS). The initial driving mechanism for the opening of the BRS is thus independent from the India-Asia collision. AFTA show a late Miocene-early Pliocene increase in tectonic extension in the BRS that confirms previous thoughts and might reflect the first significant effect of the stress field generated by the India-Asia collision.
ISSN: 0278-7407

hal-00420895
https://hal.archives-ouvertes.fr/hal-00420895
DOI : 10.1029/2008TC002404

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Aims: The aims of this study were to compare short-and long-term outcomes for clinical T2N0 oesophageal cancer with analysis of (i) primary surgery (S) versus neoadjuvant therapy plus surgery (NS), (ii) squamous cell carcinoma and adenocarcinoma subsets; and (iii) neoadjuvant chemoradiotherapy versus neoadjuvant chemotherapy.Methods: Data were collected from 30 European centres from 2000 to 2010. Among 2944 included patients, 355 patients (12.1%) had cT2N0 disease; 285 (S) and 70 (NS), were compared in terms of short-and long-term outcomes. Propensity score matching analyses were used to compensate for differences in baseline characteristics.Results: No significant differences between the groups were shown in terms of in hospital morbidity and mortality. Nodal disease was observed in 50% of S-group at the time of surgery, with 20% pN2/N3. Utilisation of neoadjuvant therapy was associated with significant tumour downstaging as reflected by increases in pT0, pN0 and pTNM stage 0 disease, this effect was further enhanced with neoadjuvant chemoradiotherapy. After adjustment on propensity score and confounding factors, for all patients and subset analysis of squamous cell and adenocarcinoma, neoadjuvant therapy had no significant effect upon survival or recurrence (overall, loco-regional, distant or mixed) compared to surgery alone. There were no significant differences between neoadjuvant chemotherapy and chemoradiotherapy in short-or long-term outcomes.Conclusion: The results of this study suggest that a surgery alone treatment approach should be recommended as the primary treatment approach for cT2N0 oesophageal cancer despite 50% of patients having nodal disease at the time of surgery.
ISSN: 0959-8049

hal-01666517
https://hal.univ-lorraine.fr/hal-01666517
DOI : 10.1016/j.ejca.2015.11.024

Éditeur(s) : HAL CCSD Elsevier
Résumé : In the context of an ongoing monitoring study on the impacts of gold-mining activities on critical ecosystem processes, we explored the use of soil Denitrifying Enzyme Activity (DEA) and Substrate Induced Respiration (SIR) as ecosystem indicators in tropical rainforests of French Guiana. We also propose DEA/SIR ratio as ecosystem attribute able to describe the state of an ecosystem and to reflect changes in ecological processes. With this purpose, we measured SIR, DEA and DEA/SIR ratio in five gold-mining areas and five surrounding natural reference rainforests. We also measured indicators in two conditions of spontaneous regeneration of vegetation (stratified or not) and two conditions of soil rehabilitation (prior preparation of soils or not). We showed a high variability of DEA, SIR and DEA/SIR ratio in the natural reference forests. This pointed out the necessity to identify relevant reference systems - i.e. proving a close match in all relevant ecological dimensions - to compare with closed perturbed systems in order to assess the levels of alterations after disturbances. Results showed a high impact of gold mine on microbial processes with a strong decrease of DEA (10-fold lower), SIR (2-fold lower) and DEA/SIR ratio (8-fold lower) in perturbed areas in comparison with natural reference forests. The type of spontaneous vegetation (stratified or not) influenced the values of indicators as well as prior rehabilitation of soils, demonstrating the capacity of DEA. SIR and DEA/SIR ratio to respond in proportion to the perturbation (robustness) and to the different levels of restoration (sensitivity). The systematic decrease of the ratio DEA/SIR observed in the studied perturbed situations demonstrates clearly that the structure of microbial communities has been also modified. The ratio DEA/SIR proved to be robust and sensitive, and able to describe in fairly fine way changes of soil microbial communities in terms of structure and function in gold mine areas and during processes of restoration. We propose to use DEA, SIR and DEA/SIR ratio as bioindicators of both structural and functional aspects of C and N cycling in soils. Together with others bioindicators based on key supporting functions in soils, these indicators should accurately evaluate the ecological potential of natural ecosystems and the levels of degradation in case of land-use changes. (C) 2012 Elsevier Ltd. All rights reserved.
ISSN: 1470-160X

hal-01190730
https://hal.archives-ouvertes.fr/hal-01190730
DOI : 10.1016/j.ecolind.2012.01.021
PRODINRA : 213639