Main-Sequence and sub-giant stars in the Globular Cluster NGC6397: The complex evolution of the lithium abundance

Thanks to the high multiplex and efficiency of Giraffe at the VLT we have been able for the first time to observe the Li I doublet in the Main Sequence (MS) stars of a Globular Cluster. At the same time we observed Li in a sample of Sub-Giant (SG) stars of the same B-V colour. Our final sample is composed of 84 SG stars and 79 MS stars. In spite of the fact that SG and MS span the same temperature range we find that the equivalent widths of the Li I doublet in SG stars are systematically larger than those in MS stars, suggesting a higher Li content among SG stars. This is confirmed by our quantitative analysis. We derived the effective temperatures, from H$\alpha$ fitting, and NLTE Li abundances of the stars in our the sample, using 3D and 1D models. We find that SG stars have a mean Li abundance higher by 0.1dex than MS stars, using both 1D and 3D models. We also detect a positive slope of Li abundance with effective temperature. These results provide an unambiguous evidence that the Li abundance changes with evolutionary status. The physical mechanisms responsible for this behaviour are not yet clear, and none of the existing models seems to describe accurately these observations. Based on these conclusions, we believe that the cosmological lithium problem still remains an open question.Comment: Proceedings of the contributed talk presented at the IAU Symposium 26

Nodal involvement evaluation in advanced cervical cancer: a single institutional experience

Purpose: To assess the usefulness of different imaging techniques in the detection of nodal involvement in patients with advanced cervical carcinoma. Moreover, to analyze the correlation between the presurgical (FIGO) and postsurgical (pTNM) staging classifications. Materials and Methods: All patients diagnosed with advanced cervical cancer (FIGO Stages IIB-IV) from 2005 to 2012 were selected. The medical charts of 51 patients that underwent presurgical assessment with posterior surgical staging by means of paraaortic lymphadenectomy, were reviewed. Nodal status assessment by computed tomography scan (CT scan), magnetic resonance imaging (MRI), positron emission tomography (PET), and sonography was compared, as well as the size given in imaging techniques compared to the final pathologic report information. Results: Presurgical analysis by CT scan, MRI, PET, and sonography showed pelvic nodal involvement in 51.3% of patients, and para-aortic involvement in 30.8% of cases. CT scan showed positive pelvic nodes in 35% of cases, but pathologic confirmation was observed in just 17.6% of cases. However, MRI resulted in higher rates of up to 48.8% of cases. Concerning para-aortic nodal involvement, CT scan showed positive nodes in 25% of cases, MRI in 3.2% of cases, and the pathologic report in 15.6% of cases. The authors found significant differences between staging groups among both classifications (FIGO vs. pTNM; p < 0.001). Eight cases (15.7%) were understaged by FIGO classification. Conclusions: Despite all imaging techniques available, none has demonstrated to be efficient enough to avoid the systematic study of para-aortic nodal status by means of surgical evaluatio

Three carbon-enhanced metal-poor dwarf stars from the SDSS - Chemical abundances from CO^5BOLD 3D hydrodynamical model atmospheres

The origin of carbon-enhanced metal-poor stars enriched with both s and r elements is highly debated. Detailed abundances of these types of stars are crucial to understand the nature of their progenitors. The aim of this investigation is to study in detail the abundances of SDSS J1349-0229, SDSS J0912+0216 and SDSS J1036+1212, three dwarf CEMP stars, selected from the Sloan Digital Sky Survey. Using high resolution VLT/UVES spectra (R ~ 30 000) we determine abundances for Li, C, N, O, Na, Mg, Al, Ca, Sc, Ti, Cr, Mn, Fe, Co, Ni and 21 neutron-capture elements. We made use of CO^5BOLD 3D hydrodynamical model atmospheres in the analysis of the carbon, nitrogen and oxygen abundances. NLTE corrections for C I and O I lines were computed using the Kiel code. We classify SDSS J1349-0229 and SDSS J0912+0216 as CEMP-r+s stars. SDSS J1036+1212 belongs to the class CEMP-no/s, with enhanced Ba, but deficient Sr, of which it is the third member discovered to date. Radial-velocity variations have been observed in SDSS J1349-0229, providing evidence that it is a member of a binary system. The chemical composition of the three stars is generally compatible with mass transfer from an AGB companion. However, many details remain difficult to explain. Most notably of those are the abundance of Li at the level of the Spite plateau in SDSS J1036+1212 and the large over-abundance of the pure r-process element Eu in all three stars.Comment: 12 pages, 15 figures. Accepted for publication in A&

Pseudoartrosis de escafoides carpiano tratadas mediante la técnica de Matti-Russe: estudio retrospectivo de 36 casos

Presentamos un estudio retrospectivo de una serie de 36 pacientes con pseudoartrosis de escafoides operados mediante la técnica de Matti-Russe entre 1985 y 1991. Utilizamos injerto córtico esponjoso obtenido del radio (50%), cresta ilíaca (42%) y cúbito (8%) sin diferencias en la incorporación. La tasa de curación fue mayor en las pseudoartrosis medias y distales (80%) que en las de localización proximal (54%). El 80% de los fracasos de curación en la localización media y distal eran pseudoartrosis de más de 30 meses de evolución. Los cambios degenerativos en el carpo de las pseudoartrosis no curadas fueron significativamente mayores (p< 0,001) que en las que se obtuvo la consolidación. La localización y la antiguedad de la pseudoartrosis parecen ser dos importantes factores pronósticos. La técnica de Matti-Russe presenta limitaciones en la pseudoartrosis de localización proximal y en los carpos muy degenerados.We reported a retrospective study of 36 patients with a pseudoarthrosis of the carpal scaphoid bone treated by the Matti-Russe operation from 1985 to 1991. We used radial (50%), iliac (42%) or ulnar (8%) autogenous grafts without any difference in the rate of incorporation. The rate of healing of the pseudoarthrosis was higher in mid and distal location (80%) than in proximal location (54%). In 80% of cases, healing failures in the mid and distal location occurred in old pseudoarthrosis ( >3 0 months evolution). Carpal degenerative changes were significantly higher (p < 0,01) in patients with not healed pseudoarthrosis. The location and the age of the pseudoarthrosis appear to be important prognostic factors. The Matti-Russe technique has limitations when is performed either in proximal pseudoarthrosis or in the presence of advanced radiocarpal osteoarthritis

Fracturas de húmero complicadas con lesión arterial

Presentamos una serie de 10 pacientes afectos de una fractura de húmero asociada a una lesión arterial, tratados entre Enero de 1990 y Octubre de 1993. Dentro de la serie distinguimos tres grupos, de acuerdo con la localización de la fractura (tercio proximal, diáfisis, región supracondílea). El análisis de los resultados sugiere que el peor pronóstico corresponde a las lesiones proximales y diafisarias por su etiología, daños asociados y menor posibilidad de circulación colateral de suplencia. El manejo de estas lesiones complejas exige un tratamiento quirúrgico interdisciplinario. Señalamos la utilidad de la fijación externa como método de osteosíntesis y el uso de un «shunt» provisional para perfundir el miembro durante la cirugía ósea. Se discute la indicación de arteriografía en los traumatismos agudos del miembro superior.A serie of 10 patients with a fracture of the humerus and associated arterial injury treated from January 1990 to October 1993 is reported. The serie was divided in 3 groups acording the proximal, mid shaft or supracondylar location of the fracture. Clinical results indicate a poor prognosis of proximal and mid shaft fractures related to their etiology, associated injuries and damage of the colateral vessels. The management of these complex injuries require an interdisciplinar approach. External fixation is an usefull stabilitation method for fractures associated with vascular damage. The utility of a temporary intraluminar vascular shunt to perfuse the limb at the bone surgery and preoperative arteriography are discussed

Open ocean temperature and salinity trends in the Canary Current Large Marine Ecosystem

The Sea Surface Temperature in the Canary Current Large Marine Ecosystem (CCLME) for the 32 years in the period 1982‐2013 shows a mean warming trend of 0.28°C decade‐1. However, this overall warming trend shows significant changes due to the influence of the different dynamical regimes that coexist in the CCLME. Near the coast, in the area under the influence of the upwelling, between Cape Blanc and Cape Beddouza, the warming trend is not statistically different from zero. Near the coast, but in the waters under the influence of downwelling, between Cape Verde and Cape Blanc, the warming trend is higher (>0.5°C decade‐1), and statistically significant. In the oceanic regions, there is a statistically significant trend of 0.25°C decade‐1, a trend that is also observed in waters shallower than the permanent thermocline (200‐ 600 dbar). This warming rate is density compensate, with an increase in salinity of 0.02 decade‐1. Neither the intermediate waters nor the upper deep waters show any statistically significant trend. The deep waters (2600‐3600 dbar) in the oceanic waters north of the Canary Islands, show a warming rate of ‐0.01°C decade‐1 and a freshening of ‐0.002 decade‐1.En prens

Seasonal Growth Curves of Perennial Ryegrass in Mexico

An experiment was established at Colegio de Postgraduados Research Station, Texcoco, México to evaluate the seasonal pattern of growth curve of perennial ryegrass (Lolium perenne) swards. Growth rate increases rapidly from a low level immediately after defoliation, and eventually reaches an equilibrium level as the amount of green leaf in the sward stabilize. The time required to reach this state varied according to the season of year, with the four seasons ranked in the order: spring (4 weeks) \u3c summer (5 weeks) \u3c autumn and winter (6 weeks). Once swards reached equilibrium, growth rates started to decline as a consequence of an increase in dead material and pseudostem. These increases were highest in spring and lowest in winter. The results of this study suggest that sward management to maximise herbage production and utilisation in ryegrass swards must be done once the highest green leaf mass is reached. In this trial, it was reached at 5, 6, 6 and 4 weeks in summer, autumn, winter and spring, respectively

Extremely metal-poor stars from the SDSS

We give a progress report about the activities within the CIFIST Team related to the search for extremely metal-poor stars in the Sloan Digital Sky Survey's spectroscopic catalog. So far the search has provided 25 candidates with metallicities around or smaller -3. For 15 candidates high resolution spectroscopy with UVES at the VLT has confirmed their extremely metal-poor status. Work is under way to extend the search to the SDSS's photometric catalog by augmenting the SDSS photometry, and by gauging the capabilities of X-shooter when going to significantly fainter targets.Comment: 6 pages, 6 figures, Proceedings paper of the conference "A stellar journey: A symposium in celebration of Bengt Gustafsson's 65th birthday