The interplay between a galactic bar and a supermassive black hole: nuclear fueling in a sub-parsec resolution galaxy simulation

We study the connection between the large-scale dynamics and the gas fueling toward a central black hole via the analysis of a Milky Way-like simulation at sub-parsec resolution. This allows us to follow a set of processes at various scales (e.g., the triggering of inward gas motion towards inner resonances via the large-scale bar, the connection to the central black hole via mini spirals) in a self-consistent manner. This simulation provides further insights on the role of shear for the inhibition of star formation within the bar in regions with significant amount of gas. We also witness the decoupling of the central gas and nuclear cluster from the large-scale disc, via interactions with the black hole. This break of symmetry in the mass distribution triggers the formation of gas clumps organised in a time-varying 250 pc ring-like structure, the black hole being offset by about 70 pc from its centre. Some clumps form stars, while most get disrupted or merge. Supernovae feedback further creates bubbles and filaments, some of the gas being expelled to 100 pc or higher above the galaxy plane. This helps remove angular momentum from the gas, which gets closer to the central dark mass. Part of the gas raining down is being accreted, forming a 10~pc polar disc-like structure around the black hole, leading to an episode of star formation. This gives rise to multiple stellar populations with significantly different angular momentum vectors, and may lead to a natural intermittence in the fueling of the black hole.Comment: Accepted for publication in MNRAS, 15 pages, 13 figure

Results of combined treatment of anaplastic thyroid carcinoma (ATC)

<p>Abstract</p> <p>Background</p> <p>Anaplastic thyroid carcinoma (ATC) is among the most aggressive human malignancies. It is associated with a high rate of local recurrence and with poor prognosis.</p> <p>Methods</p> <p>We retrospectively reviewed 44 consecutive patients treated between 1996 and 2010 at Leon Berard Cancer Centre, Lyon, France. The combined treatment strategy derived from the one developed at the Institut Gustave Roussy included total thyroidectomy and cervical lymph-node dissection, when feasible, combined with 2 cycles of doxorubicin (60 mg/m2) and cisplatin (100 mg/m2) Q3W, hyperfractionated (1.2 Gy twice daily) radiation to the neck and upper mediastinum (46-50 Gy), and then four cycles of doxorubicin-cisplatin.</p> <p>Results</p> <p>Thirty-five patients received the three-phase combined treatment. Complete response after treatment was achieved in 14/44 patients (31.8%). Eight patients had a partial response (18.2%). Twenty-two (50%) had progressive disease. All patients with metastases at diagnosis died shortly afterwards. Thirteen patients are still alive. The median survival of the entire population was 8 months.</p> <p>Conclusion</p> <p>Despite the ultimately dismal prognosis of ATC, multimodality treatment significantly improves local control and appears to afford long-term survival in some patients. There is active ongoing research, and results obtained with new targeted systemic treatment appear encouraging.</p

Evolution des galaxies (interactions, fusions, et accrétion de gaz)

PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Thyroid cancer: is the incidence rise abating?

OBJECTIVE: The aim of the present study was to determine recent trends in thyroid cancer incidence rates and to analyze histopathological characteristics and geographical distribution. METHODS: Histologically proven 5367 cases were collected over the period 1998-2006 in France from the Rhône-Alpes thyroid cancer registry. Geographical variations of incidence were analyzed using a mixed Poisson model. RESULTS: The average incidence rates, age standardized to the world population, were 3.9/100,000 in men and 12.3/100,000 in women, higher than those previously reported in France. After an initial increase during the first 3 years, a steady level of incidence was observed for the period 2001-2006. The annual incidence rate of microcarcinomas was correlated with that of all cancers in men and women (r=0.78 and 0.89; P<0.01) respectively. Papillary microcarcinomas represented 38% of tumors and two-thirds of them measured less than 5 mm in diameter. They were fortuitously discovered after thyroidectomy for benign diseases in 64% of cases. Histological marks of aggressiveness differed according to the size of the tumor. Despite recent advances in diagnosis, 13% of tumors were diagnosed at advanced stage especially in men. Geographical distribution of incidence based on subregional administrative entities showed lower incidence rates in rural than in urban zones in men (relative rate: 0.72; 95% CI: 0.62-0.84) and women (relative rate: 0.85; 95% CI: 0.73-0.93). CONCLUSION: The present study suggests that the rise in thyroid cancer incidence is now abating. It could reflect standardization in diagnostic procedures. Further studies, performed on a more prolonged period, are necessary to confirm these data