The Evolution of Anodic Hydrogen on High Purity Magnesium in Acidic Buffer Solution

Hydrogen evolution (HE) on anodically polarized Mg, commonly referred to as Negative Difference Effect, was studied by galvanodynamic measurements coupled with real-time gravimetric H2 volume collection, the Scanning Vibrating Electrode Technique and potentiodynamic polarization experiments. High purity Mg (99.96% Mg) electrodes were studied in chloride-free 0.1 M citric acid solution buffered at pH with the aim of determining the source of anodic HE and the role of the corrosion film on the process. In such conditions of pH, the typical dark corrosion product exhibited in neutral and alkaline solutions was not found but the HE rate still increased with increasing potential. Evidence that HE on dissolving high purity Mg is associated with the regions dominated by the anodic dissolution reaction is provided. The role of noble impurity enrichment on the electrode surface during anodic polarization and the effect of Fe re-deposition are also discussed

The composition of circumstellar gas and dust in 51 Oph

We analyze ISO archive data of the nearby bright emission-line star 51 Oph, previously classified as a proto-planetary system similar to beta Pic. The infrared spectrum reveals the presence of gas-phase emission bands of hot (approx 850 K) CO, CO_2, H_2O and NO. In addition to this, partially crystalline silicate dust is present. The solid-state bands and the energy distribution are indicative of dust that has formed recently, rather than of debris dust. The presence of hot molecular gas and the composition of the circumstellar dust are highly unusual for a young star and are reminiscent of what is found around evolved (AGB) stars, although we exclude the possibility of 51 Oph belonging to this group. We suggest several explanations for the nature of 51 Oph, including a recent episode of mass loss from a Be star, and the recent destruction of a planet-sized body around a young star.Comment: 4 pages, 3 figures, accepted by A&A (letters

Structure and Colors of Diffuse Emission in the Spitzer Galactic First Look Survey

We investigate the density structure of the interstellar medium using new high-resolution maps of the 8 micron, 24 micron, and 70 micron surface brightness towards a molecular cloud in the Gum Nebula, made as part of the Spitzer Space Telescope Galactic First Look Survey. The maps are correlated with 100 micron images measured with IRAS. At 24 and 70 micron, the spatial power spectrum of surface brightness follows a power law with spectral index -3.5. At 24 micron, the power law behavior is remarkably consistent from the 0.2 degree size of our maps down to the 5 arcsecond spatial resolution. Thus, the structure of the 24 micron emission is self-similar even at milliparsec scales. The combined power spectrum produced from Spitzer 24 micron and IRAS 25 micron images is consistent with a change in the power law exponent from -2.6 to -3.5. The decrease may be due to the transition from a two-dimensional to three-dimensional structure. Under this hypothesis, we estimate the thickness of the emitting medium to be 0.3 pc.Comment: 13 Pages, 3 Figures, to be published in Astrophysical Journal Supplement Series (Spitzer Special Issue), volume 154. Uses aastex v5.

Aeolian transport of viable microbial life across the Atacama Desert, Chile : Implications for Mars

A.A.B. and A.G.F. thank the Project “icyMARS”, funded by the European Research Council, ERC Starting Grant No. 307496. M.P.Z., C.G.S., R.F. and F.J.M.T. thank the funding received from the Dubai Future Foundation through the Guaana.com open research platform (https://www.guaana.com/projects/jeGEimuX6DLCLsbQP).Peer reviewedPublisher PD

Efecto de las intervenciones con ingesta de leguminosas y/o ejercicio supervisado sobre el perfil lipídico de mujeres jóvenes, sanas y sedentarias

Objective: To contribute to the knowledge of some aspects of the Healthy Life Style by studying the effects of including legumes in the diet and exercise at two intensity levels, along with the lipid profile of young sedentary women living at 2640 meters above sea level. Materials and methods: The study included a non-randomized clinical trial with four intervention groups: exercise at 45% VO2 peak plus legumes in diet, exercise at 65% VO2 peak plus legumes in diet, only exercise at 65% VO2 peak, and only inclusion of legumes in diet. In each group, 20 to 23 sedentary women were included. The intervention was carried out for four weeks, three days a week. Exercise prescription was based on measurement of VO2 peak by ergospirometry; and the current intervention was monitored with heart-rate monitors. The outcome variables were total serum cholesterol, LDL cholesterol, HDL cholesterol, and triacylglycerols measured at baseline and after two and four weeks of intervention. Results: The measurements taken of participants in the group of exercise at 65% VO2 peak plus legumes in diet showed a reduction of 19.8 mg/dl in total cholesterol, of 21.8 mg/dl of LDL cholesterol, of 20.7 mg/dl of tracylglycerol, and an increase of 6.2 mg/dl of HDL cholesterol. The serum levels of HDL also increased in the group of only exercise at 65% VO2 peak. No significant changes in serum levels were documented for participants in the group with only dietary modifications. Conclusions: The results suggest that different interventions that meet some of the criteria for healthy eating and life style show different effects with regards to the level of change in the lipid profile components. Objetivo: Contribuir al conocimiento de algunos aspectos prácticos para llevar a cabo una alimentación y estilo de vida saludable, mediante el estudio de los efectos en el perfil lipídico de la inclusión de leguminosas (fríjol, lenteja y garbanzos) en la dieta de mujeres sanas pero sedentarias, acompañada de ejercicio con dos niveles de intensidad, moderada y alta, efectuados a una altura de 2,640 metros sobre el nivel del mar (msnm) Material y métodos: Estudio de intervención clínica no aleatorizada con cuatro grupos de intervención: ejercicio a 45% VO2 pico + leguminosas, ejercicio a 65% VO2 pico + leguminosas, sólo ejercicio a 45% VO2 picoy sólo inclusión de leguminosas en la dieta. En cada grupo se incluyeron de 20 a 23 mujeres jóvenes sedentarias evaluadas mediante el International Physical Activity Questionnaire (IPAQ), y la intervención se llevó a cabo durante 4 semanas. La prescripción del ejercicio se hizo previa determinación del VO2 pico por ergo espirometría, y su realización se monitoreó con sensores de frecuencia cardíaca. El efecto de la intervención se evaluó mediante los cambios en los niveles séricos de colesterol total (CT), colesterol LDL (cLDL), colesterol HDL (cHDL) y triacilgliceroles (TAG), tomados a las semanas cero, dos y cuatro. Resultados: En el grupo «ejercicio a 65% del VO2 pico, más inclusión de leguminosas en la dieta» se obtuvieron los siguientes resultados significantes: una reducción promedio del colesterol total de 19.8 mg/dl (p=0.0015), del colesterol LDL de 21.8 mg/dl (p=0.0001), un aumento de colesterol HDL de 6.2 mg/dl (p=0.0001) y una disminución de los triacilgliceroles de 20.7 mg/dl (p=0.0001). En el grupo de sólo ejercicio a 65% del VO2 pico se obtuvo un aumento del HDL. No hubo modificaciones al perfil lipídico en el grupo correspondiente a sólo inclusión de leguminosas en la alimentación. Conclusiones: Los resultados sugieren que en mujeres jóvenes sedentarias que viven a 2,640 metros sobre el nivel del mar, la combinación de ejercicio de intensidad alta e inclusión de leguminosas (fríjol, lenteja o garbanzos) producen un mayor cambio benéfico en el perfil lipídico que una intervención con sólo ejercicio de intensidad alta o sólo inclusión de leguminosas en la alimentación. Los cambios benéficos significantes se obtuvieron luego de 4 semanas de intervención en el colesterol total, colesterol LDL, colesterol HDL y triacilgliceroles, lo que pone de presente la bondad de esta intervención, así como la utilidad del perfil lipídico como indicador temprano de cambios en los estilos de vida. Las intervenciones estudiadas, compatibles con alimentación y estilo de vida saludables, producen efectos diferentes en los niveles del perfil lipídico estudiados, y al poner de presente las debilidades de un diseño no aleatorizado, se puede recomendar que se insista en las intervenciones de salud pública que contemplen cambios en la dieta y cambios en la actividad física

Desempenho de ovelhas e cordeiros manejados com diferentes métodos de pastoreio e ofertas de forragem em campo natural

The objective of was to determine the influence of grazing methods with a relatively low or high herbage allowance in the first 84 gestation days on ewes/lambs daily weight gain (DWG) and area production. The study was conducted at an 8.4 ha natural grassland in South Brazil. During the winter, early pregnancy ewes were submitted to two grazing methods (continuous (CS) and rotative (RS) stoking) and two herbage allowances (HA; 12 and 18% live weight)), resulting in four treatments: CS18, CS12, RS18 and RS12. It was measured the DWG and body condition score (BCS) from ewes and from ewes and lambs after born, as well lambs area production. During the winter only the HA change the DWG from the ewes. During the spring differences were found only in the lambs DWG from grazing method, been higher in CS. A grazing method × HA interaction indicate that the higher lambs area production was achieved in the CS12 treatment. The results indicate that the grazing methods and HA had a little influence in the animal performance over winter and the herbage could be better used in this period.O objetivo foi determinar a influência dos métodos de pastoreio com uma relativa baixa e alta oferta de forragem nos primeiros 84 dias de gestação no desempenho de ovelhas e seus cordeiros após o nascimento. O trabalho foi conduzido em 8,4 ha de campo natural, quando os animais foram submetidos a diferentes métodos de pastoreio (lotação contínua (LC) e rotativa (LR)) e ofertas de forragem (OF, 12 e 18% do peso vivo (PV)), gerando quatro tratamentos: LC12, LC18, LR12 e LR18. Foi medido o ganho médio diário (GMD) das ovelhas e cordeiros e a condição corporal das ovelhas assim como a produção de cordeiros por área. No inverno o GMD somente foi modificado pelas OF. Na primavera, somente o GMD dos cordeiros apresentou efeito e somente para métodos de pastoreio, sendo o melhor desempenho encontrado nos cordeiros nascidos de ovelhas manejadas no inverno sob LC. Uma interação métodos × OF indicou que a maior produção por área de cordeiros foi no obtida em LC12. Os resultados indicam que os métodos de pastoreio e as OF tem pouca influência no desempenho animal no inverno e pode-se fazer uma melhor utilização da forragem neste período

thrombosis of the portal venous system in cirrhotic patients

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Is radiotherapy required in first-line treatment of stage I diffuse anaplastic Wilms tumor? A report of SIOP-RTSG, AIEOP, JWiTS, and UKCCSG

BACKGROUND: As a significant proportion of relapses occurred in the tumor bed or abdomen on patients with the fifth National Wilms Tumor Study stage I anaplastic Wilms tumor (WT), flank radiotherapy was added for stage I anaplastic WT in the subsequent study of the Children's Oncology Group (AREN0321). Preliminary results revealed reduction of relapse rate and improved survival. In cases treated with preoperative chemotherapy, such as in International Society of Pediatric Oncology (SIOP), the value of radiotherapy has never been studied. The aim of this observational study is to describe the pattern of recurrence and survival of patients with stage I diffuse anaplastic WT (DAWT) after induction chemotherapy. METHODS: Retrospective data analysis of the pattern of relapse and survival of all patients with stage I DAWT were included in recent SIOP, L'Associazone Italiana Ematologica Oncologia Pediatrica (AIEOP), Japan Wilms Tumor Study Group (JWiTS), United Kingdom Children's Cancer Study Group (UKCCSG) renal tumor registries. Postoperative treatment consisted of actinomycin D, vincristine, and doxorubicin for 28 weeks without local irradiation. RESULTS: One hundred nine cases with stage I DAWT were identified, of which 95 cases received preoperative chemotherapy. Of these, seven patients underwent preoperative true‐cut biopsy. Sixteen of the 95 patients relapsed (17%), six locally, four at distant site, and six combined, and all treated according to SIOP 2001 relapse protocol, which resulted in a 5‐year overall survival of 93%. CONCLUSION: Despite 13% locoregional relapse rate, an excellent rescue rate was achieved after salvage treatment, in patients with stage I DAWT whose first‐line treatment comprised three‐drug chemotherapy (including doxorubicin), without flank irradiation. Therefore, we continue not to advocate the use of radiotherapy in first‐line treatment after preoperative chemotherapy in stage I DAWT in the next SIOP protocol