A study of the elements copper through uranium in Sirius A: Contributions from STIS and ground-based spectra

We determine abundances or upper limits for all of the 55 stable elements from copper to uranium for the A1 Vm star Sirius. The purpose of the study is to assemble the most complete picture of elemental abundances with the hope of revealing the chemical history of the brightest star in the sky, apart from the Sun. We also explore the relationship of this hot metallic-line (Am) star to its cooler congeners, as well as the hotter, weakly- or non-magnetic mercury-manganese (HgMn) stars. Our primary observational material consists of {\em Hubble Space Telescope} ($HST$) spectra taken with the Space Telescope Imaging Spectrograph (STIS) in the ASTRAL project. We have also used archival material from the %\citep/{ayr10}. $COPERNICUS$ satellite, and from the $HST$ Goddard High-Resolution Spectrograph (GHRS), as well as ground-based spectra from Furenlid, Westin, Kurucz, Wahlgren, and their coworkers, ESO spectra from the UVESPOP project, and NARVAL spectra retrieved from PolarBase. Our analysis has been primarily by spectral synthesis, and in this work we have had the great advantage of extensive atomic data unavailable to earlier workers. We find most abundances as well as upper limits range from 10 to 100 times above solar values. We see no indication of the huge abundance excesses of 1000 or more that occur among many chemically peculiar (CP) stars of the upper main sequence. The picture of Sirius as a hot Am star is reinforced.Comment: With 6 Figures and 4 Tables; accepted for publication in Ap

BUSCA de Biomarcadores em Longevidade Humana: Investigação dos Genes Mthfd1l e Serpina3

A longevidade humana, tempo que excede a expectativa média de vida da população, é uma característica multifatorial determinada por fatores ambientais e de predisposição genética. Apesar de vários estudos investigarem a influência de componentes ambientais na longevidade, o papel de variantes genéticas nesta característica ainda não está bem esclarecido. Genes que participam do metabolismo de aminoácidos e genes que atuam em processos inflamatórios, como os genes MTHFD1L e SERPINA3, respectivamente, poderiam influenciar nas variações de tempo de vida de indivíduos de uma população. Assim, este estudo teve como objetivo avaliar se existe associação dos polimorfismos de MTHFD1L (rs11754661) e SERPINA3 (rs4934) com a longevidade humana em indivíduos atendidos em um hospital de referência no atendimento de geriatria da Grande Vitória-ES, Brasil. Foram selecionados 436 participantes, divididos em grupos de longevos (acima de 85 anos) e idosos com idade próxima a expectativa de vida da população (entre 70 e 75 anos). A genotipagem foi realizada por PCR em tempo real e os polimorfismos identificados estavam em equilíbrio de Hardy-Weinberg. As análises estatísticas foram realizadas por meio dos testes de Odds Ratio (OR) com Intervalo de Confiança de 95%, χ² e Fisher, com p-value ≤0,05. Não foi observada associação do polimorfismo rs4934 do gene SERPINA3 com a longevidade. Todavia, o alelo G do polimorfismo rs11754661 do gene MTHFD1L se comportou como um alelo de risco para a longevidade humana na população analisada (p=0,027; OR=1,976; IC 95% variando de 1,080 a 3,616), bem como o genótipo GG (p=0,030; OR=2,006; IC 95% variando de 1,070-3,761), enquanto que o genótipo AG atuou como fator de proteção (p=0,041; OR=0,518; IC 95% variando de 0,275 a 0,974). Os resultados sugerem que o polimorfismo rs11754661 do gene MTHFD1L está associado com a longevidade humana na amostra de indivíduos da Grande Vitória-ES, Brasil e que o polimorfismo rs4934 do gene SERPINA3 não está associado com longevidade na amostra avaliada

Acceptability of, and barriers and facilitators to, a pilot physical health service for people who inject drugs: A qualitative study with service users and providers

BACKGROUND: People who inject drugs may experience difficulty accessing or maintaining involvement with traditional healthcare services. This is associated with increased health inequalities and bio-psychosocial difficulties. Embedding physical healthcare services within community-based drug services may provide a practical and feasible approach to increase access and delivery of healthcare. This study explored the acceptability of, and barriers and facilitators to, embedding a pilot physical healthcare service within a community-based drug service in the United Kingdom (Bristol, England). METHODS: Semi-structured interviews were conducted with service users (people who inject drugs) (n = 13), and a focus group was conducted with service providers (n = 11: nine harm reduction workers, two nurses, one service manager). Topic guides included questions to explore barriers and facilitators to using and delivering the service (based on the COM-B Model), and acceptability of the service (using the Theoretical Framework of Acceptability). Transcripts were analysed using a combined deductive framework and inductive thematic analysis approach. RESULTS: The service was viewed as highly acceptable. Service users and providers were confident they could access and provide the service respectively, and perceived it to be effective. Barriers included competing priorities of service users (e.g. drug use) and the wider service (e.g. equipment), and the potential impact of the service being removed in future was viewed as a barrier to overall healthcare access. Both service users and providers viewed embedding the physical health service within an existing community-based drug service as facilitating accessible and holistic care which reduced stigma and discrimination. CONCLUSIONS: The current study demonstrated embedding a physical health service within an existing community-drug based and alcohol service was acceptable and beneficial. Future studies are required to demonstrate cost-effectiveness and ensure long-term sustainability, and to determine transferability of findings to other settings, organisations and countries

Animal Defenses against Infectious Agents: Is Damage Control More Important Than Pathogen Control?

The ability of hosts to withstand a given number of pathogens is a critical component of health. Now playing catch-up with plant biologists, animal biologists are starting to formally separate this form of defense from classical resistance

Influence of seasonality on ovulatory follicular wave dynamic in long protocols in Santa Inês sheep in the tropics.

Edição dos proceedings da Annual Conference or the International Embryo Transfer Society, Orlando, Florida, 2011

ZnO thin films implanted with Al, Sb and P : optical, structural and electrical characterization

In this work we report a study on the structure, optical and electrical properties of P, Sb and Al implanted ZnO thin films that had been produced by r.f. magnetron sputtering. The influence of the different replacing atoms on the structure and properties of the films has been explored. Looking for the best annealing conditions, two different annealing temperatures (300ºC and 500ºC) have been employed. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction, transmittance and d.c conductivity measurements have been used to characterize the samples. X-ray diffraction and Raman scattering patterns confirm that after annealing, doped films keep a polycrystalline nature with (002) preferred orientation. These films remain very transparent and the electrical conductivity increases significantly after the 500ºC annealing, reaching values of 10.9 (cm)-1 in the P-doped, 10.33 (cm)-1 in the Al-doped and 0.56 (cm)-1 in the Sb-doped sample

Biomass fuel use and indoor air pollution in homes in Malawi

Background: Air pollution from biomass fuels in Africa is a significant cause of mortality and morbidity both in adults and children. The work describes the nature and quantity of smoke exposure from biomass fuel in Malawian homes. Methods: Markers of indoor air quality were measured in 62 homes (31 rural and 31 urban) over a typical 24 h period. Four different devices were used (one gravimetric device, two photometric devices and a carbon monoxide (HOBO) monitor. Gravimetric samples were analysed for transition metal content. Data on cooking and lighting fuel type together with information on indicators of socioeconomic status were collected by questionnaire. Results: Respirable dust levels in both the urban and rural environment were high with the mean (SD) 24 h average levels being 226 μg/m3 (206 μg/m3). Data from real-time instruments indicated respirable dust concentrations were >250 μg/m3 for >1 h per day in 52% of rural homes and 17% of urban homes. Average carbon monoxide levels were significantly higher in urban compared with rural homes (6.14 ppm vs 1.87 ppm; p<0.001). The transition metal content of the smoke was low, with no significant difference found between urban and rural homes. Conclusions: Indoor air pollution levels in Malawian homes are high. Further investigation is justified because the levels that we have demonstrated are hazardous and are likely to be damaging to health. Interventions should be sought to reduce exposure to concentrations less harmful to health