The magnetic nature of disk accretion onto black holes

Although disk accretion onto compact objects - white dwarfs, neutron stars, and black holes - is central to much of high energy astrophysics, the mechanisms which enable this process have remained observationally elusive. Accretion disks must transfer angular momentum for matter to travel radially inward onto the compact object. Internal viscosity from magnetic processes and disk winds can in principle both transfer angular momentum, but hitherto we lacked evidence that either occurs. Here we report that an X-ray-absorbing wind discovered in an observation of the stellar-mass black hole binary GRO J1655-40 must be powered by a magnetic process that can also drive accretion through the disk. Detailed spectral analysis and modeling of the wind shows that it can only be powered by pressure generated by magnetic viscosity internal to the disk or magnetocentrifugal forces. This result demonstrates that disk accretion onto black holes is a fundamentally magnetic process.Comment: 15 pages, 2 color figures, accepted for publication in Nature. Supplemental materials may be obtained by clicking http://www.astro.lsa.umich.edu/~jonmm/nature1655.p

Feedback and the Formation of Dwarf Galaxy Stellar Halos

Stellar population studies show that low mass galaxies in all environments exhibit stellar halos that are older and more spherically distributed than the main body of the galaxy. In some cases, there is a significant intermediate age component that extends beyond the young disk. We examine a suite of Smoothed Particle Hydrodynamic (SPH) simulations and find that elevated early star formation activity combined with supernova feedback can produce an extended stellar distribution that resembles these halos for model galaxies ranging from $v_{200}$ = 15 km s$^{-1}$ to 35 km s$^{-1}$, without the need for accretion of subhalos.Comment: 15 pages, 15 figures, accepted MNRA

Quantitative-spatial assessment of soil contamination in S. Francisco de Assis due to mining activity of the Panasqueira mine (Portugal)

Through the years, mining and beneficiation processes produces large amounts of As-rich mine wastes laid up in huge tailings and open-air impoundments (Barroca Grande and Rio tailings) that are the main source of pollution in the surrounding area once they are exposed to the weathering conditions leading to the formation of AMD and consequently to the contamination of the surrounding environments, in particularly soils. In order to investigate the environmental contamination impact on S. Francisco de Assis (village located between the two major impoundments and tailings) agricultural soils, a geochemical survey was undertaken to assess toxic metals associations, related levels and their spatial distribution, and to identify the possible contamination sources. According to the calculated contamination factor, As and Zn have a very high contamination factor giving rise to 65.4 % of samples with a moderate to high pollution degree; 34.6 % have been classified as nil to very low pollution degree. The contamination factor spatial distribution put in evidence the fact that As, Cd, Cu, Pb, and Zn soils contents, downstream Barroca Grande tailing, are increased when compared with the local Bk soils. The mechanical dispersion, due to erosion, is the main contamination source. The chemical extraction demonstrates that the trace metals distribution and accumulation in S. Francisco de Assis soils is related to sulfides, but also to amorphous or poorly crystalline iron oxide phases. The partitioning study allowed understanding the local chemical elements mobility and precipitation processes, giving rise to the contamination dispersion model of the study area. The wind and hydrological factors are responsible for the chemical elements transport mechanisms, the water being the main transporter medium and soils as one of the possible retention media

Erratum to : Analysis of the mitochondrial maxicircle of Trypanosoma lewisi, a neglected human pathogen

BACKGROUND The haemoflagellate Trypanosoma lewisi is a kinetoplastid parasite which, as it has been recently reported to cause human disease, deserves increased attention. Characteristic features of all kinetoplastid flagellates are a uniquely structured mitochondrial DNA or kinetoplast, comprised of a network of catenated DNA circles, and RNA editing of mitochondrial transcripts. The aim of this study was to describe the kinetoplast DNA of T. lewisi. METHODS/RESULTS In this study, purified kinetoplast DNA from T. lewisi was sequenced using high-throughput sequencing in combination with sequencing of PCR amplicons. This allowed the assembly of the T. lewisi kinetoplast maxicircle DNA, which is a homologue of the mitochondrial genome in other eukaryotes. The assembly of 23,745 bp comprises the non-coding and coding regions. Comparative analysis of the maxicircle sequence of T. lewisi with Trypanosoma cruzi, Trypanosoma rangeli, Trypanosoma brucei and Leishmania tarentolae revealed that it shares 78 %, 77 %, 74 % and 66 % sequence identity with these parasites, respectively. The high GC content in at least 9 maxicircle genes of T. lewisi (ATPase6; NADH dehydrogenase subunits ND3, ND7, ND8 and ND9; G-rich regions GR3 and GR4; cytochrome oxidase subunit COIII and ribosomal protein RPS12) implies that their products may be extensively edited. A detailed analysis of the non-coding region revealed that it contains numerous repeat motifs and palindromes. CONCLUSIONS We have sequenced and comprehensively annotated the kinetoplast maxicircle of T. lewisi. Our analysis reveals that T. lewisi is closely related to T. cruzi and T. brucei, and may share similar RNA editing patterns with them rather than with L. tarentolae. These findings provide novel insight into the biological features of this emerging human pathogen

Aspectos biológicos da evolução das penas : uma revisão integrativa

The tretapod teguments has undergone several modifications throughout the their evolution, which it includes living and extinct groups, and it is related to several adaptive advantages, as the case of feather, a morphological trait that is currently restricted to birds. This character is the result of the tegument evolution in reptile groups since the Triassic. In this sense, this literature review aimed to investigate publications on the origin of feathers, their possible morphologies and ancestral stages, their development in living birds, the adaptive impacts of feathers and which groups presented feathers or their possible precursor stages. The ancestral feathers possibly arised in the Avemetatarsalia group whose origin refers to the Triassic period and would be structures that would enable thermal insulation and thus maintain higher metabolic rates than other groups in a competitive environment. Although there is no fossil evidence tracing morphological changes in feathers since their origin, an evolutionary model is accepted leading totake into account the evolutionary novelties that feathers present during their development in a characteristic scenario of Evo-Devo. O tegumento dos tetrápodes passou por diversas modificações ao longo da evolução desse grupo taxonômico, o que inclui grupos viventes e extintos, e que estão relacionadas a diversas vantagens adaptativas, como é o caso das penas, traço morfológico este restrito atualmente às aves. Esse caráter é resultante da evolução do tegumento em grupos de répteis desde o Triássico. Nesse sentido, este trabalho de revisão bibliográfica objetivou investigar publicações sobre a origem das penas, suas possíveis morfologias e estágios ancestrais, o desenvolvimento delas nas aves viventes, os impactos adaptativos das penas e quais os grupos que apresentaram penas ou seus possíveis estágios precursores. As penas ancestrais, possivelmente, surgiram no grupo Avemetatarsalia cuja origem remete ao Período Triássico e seriam estruturas que possibilitariam o isolamento térmico e, com isto, manter taxas metabólicas mais altas que outros grupos em um ambiente competitivo. Embora não existam evidências fósseis que tracem as modificações morfológicas ocorridas nas penas desde a sua origem, um modelo evolutivo é aceito levando-se em consideração as novidades evolutivas que as penas apresentam durante o seu desenvolvimento em um cenário característico de Evo-Devo

Cobertura vacinal contra influenza em gestantes da região Sudeste do Brasil: análise de 2010-2020

Objective: To analyze the influenza vaccination coverage in pregnant women in the Southeast region of Brazil between years 2010 and 2020. Methods: An ecological, time series study conducted with data from the National Immunization Program Information System (SI-PNI) referring to records of doses of influenza vaccine in pregnant women in the state of Minas Gerais. Results: Adequate vaccination coverage was achieved in only four out of the 11 years studied, ranging from 49.75% in 2011 to 88.5% in 2015. In 2020, the rate of 80.82% was reached. Possible determinants are discussed in an expanded perspective that can support the planning of actions across the country. Conclusion: Influenza vaccination coverage in pregnant women showed a stagnation trend for the most part, pointing to the possible need for continuing education of health professionals involved in antenatal care and qualification of their actions in the area of health education to clarify pregnant women’s doubts on the subject.Objetivo: Analisar a cobertura vacinal contra a influenza em gestantes na região Sudeste do Brasil, nos anos de 2010 a 2020. Métodos: Estudo ecológico, de série temporal, realizado com dados do Sistema de Informação do Programa Nacional de Imunizações (SI-PNI), referentes aos registros de doses da vacina contra influenza em gestantes no estado de Minas Gerais. Resultados: A cobertura vacinal adequada foi alcançada em apenas quatro dos 11 anos estudados, variando de 49,75% em 2011 a 88,5% em 2015. No ano de 2020 foi alcançado 80,82%. Possíveis determinantes são discutidos em uma perspectiva ampliada, que pode subsidiar planejamento de ações em todo o país. Conclusão: A cobertura vacinal contra Influenza nas gestantes apresentou, em sua maior parte, uma tendência estacionária, apontando para a possível necessidade de educação permanente dos profissionais de saúde envolvidos no pré-natal, qualificação de suas ações na área de educação em saúde para esclarecer dúvidas das gestantes sobre a temática

Factors associated with advanced-stage oral and oropharyngeal squamous cell carcinoma in a Brazilian population

Diagnosis of oral and oropharyngeal cancer in advanced stages may be associated with social nature factors, access to health care, education, occupation, and behavioral/ cultural factors. Aim: To determine the factors related to high clinical-staging in patients diagnosed with squamous cell carcinoma in the oral and oropharyngeal region in a Cancer Center in Brazil between 2009 and 2015. Methods: It is an epidemiological, retrospective, and exploratory study. Patients diagnosed with squamous cell carcinoma had their medical records analyzed. The variables considered were sociodemographic, lifestyle, and disease characteristics. Descriptive and exploratory tests (Pearson’s, chi-square test and, Student’s t-test) were realized. Results: We analyzed 365 patient records, among which 289 (79.17%) were male, and 73 (20.0%) were female. Age ranged from 16 to 101 years, with a mean of 61.13. Regarding education, 157 (43.01%) studied < 8 years, 103 (28.21%) were illiterate and 102 (27.94%) studied > 8 years. 305 (83.56%) patients live in urban areas. There was an association between high clinical-staging and low educational level. For high clinical-staging, symptomatology, tobacco, and alcohol intake as well. Conclusion: Patients with low educational levels tend to report the disease later, and their diagnostics occurred in advanced stages. Thus, specific public health policies for this population, including access to dental care to recognize the clinical signs and early diagnosis, are necessary

The Trypanosoma cruzi Sylvio X10 strain maxicircle sequence: the third musketeer

<p>Abstract</p> <p>Background</p> <p>Chagas disease has a diverse pathology caused by the parasite <it>Trypanosoma cruzi</it>, and is indigenous to Central and South America. A pronounced feature of the trypanosomes is the kinetoplast, which is comprised of catenated maxicircles and minicircles that provide the transcripts involved in uridine insertion/deletion RNA editing. <it>T. cruzi </it>exchange genetic material through a hybridization event. Extant strains are grouped into six discrete typing units by nuclear markers, and three clades, A, B, and C, based on maxicircle gene analysis. Clades A and B are the more closely related. Representative clade B and C maxicircles are known in their entirety, and portions of A, B, and C clades from multiple strains show intra-strain heterogeneity with the potential for maxicircle taxonomic markers that may correlate with clinical presentation.</p> <p>Results</p> <p>To perform a genome-wide analysis of the three maxicircle clades, the coding region of clade A representative strain Sylvio X10 (a.k.a. Silvio X10) was sequenced by PCR amplification of specific fragments followed by assembly and comparison with the known CL Brener and Esmeraldo maxicircle sequences. The clade A rRNA and protein coding region maintained synteny with clades B and C. Amino acid analysis of non-edited and 5'-edited genes for Sylvio X10 showed the anticipated gene sequences, with notable frameshifts in the non-edited regions of Cyb and ND4. Comparisons of genes that undergo extensive uridine insertion and deletion display a high number of insertion/deletion mutations that are likely permissible due to the post-transcriptional activity of RNA editing.</p> <p>Conclusion</p> <p>Phylogenetic analysis of the entire maxicircle coding region supports the closer evolutionary relationship of clade B to A, consistent with uniparental mitochondrial inheritance from a discrete typing unit TcI parental strain and studies on smaller fragments of the mitochondrial genome. Gene variance that can be corrected by RNA editing hints at an unusual depth for maxicircle taxonomic markers, which will aid in the ability to distinguish strains, their corresponding symptoms, and further our understanding of the <it>T. cruzi </it>population structure. The prevalence of apparently compromised coding regions outside of normally edited regions hints at undescribed but active mechanisms of genetic exchange.</p

Team Work: reflections of urgency and emergency service managers

Introduction: Working as a team means joining forces in a collective way with the goal of achieving goals and / or solving problems in an organization. In the health services, teamwork can be consolidated with the aid of well-defined work routines and protocols to organize the work process and establish priorities. Objective: To understand the meaning of Team Work for health managers filled in emergency and emergency units. Methods: A descriptive study with a qualitative approach in which recorded interviews were conducted with 13 managers filled in the emergency room of 4 hospitals of the Hospital Foundation of the State of Minas Gerais, located in the city of Belo Horizonte, which provide emergency and emergency care to population. For the analysis of the data the technique of analysis of the content by the reference of Bardin was used. Results: From the analysis emerged three categories: (a) Without Teamwork there is no way to carry out the activities; (b) Training as a tool for building and improving Teamwork; and (c) Motivation: the difference lies in people. Conclusions: The Teamwork allows transformations in the mentality and the work methods, occupying a large and significant space in the construction of mechanisms in favor of organizational success. In order for the necessary transformations to take place, it is necessary to count on committed human beings interested in the work and for the health organization to invest in training, skills development and continuous and continuing education, in order to stimulate participation, innovation and creativity.Introdução: Trabalhar em equipe significa unir esforços de forma coletiva com o objetivo de conseguir atingir metas e/ou resolver problemas em uma organização. Nos serviços de saúde o trabalho em equipe pode ser consolidado com auxílio de protocolos e rotinas de trabalho bem definidos com o objetivo organizar o processo de trabalho e estabelecer prioridades. Objetivo: Compreender o significado do Trabalho em Equipe para gestores de saúde lotados em unidades de urgência e emergência. Método: Estudo descritivo, com abordagem qualitativa em que se realizaram entrevistas gravadas com 13 gestores lotados no setor de pronto-socorro de 4 hospitais da Fundação Hospitalar do Estado de Minas Gerais, situados na cidade de Belo Horizonte, que prestam assistência de urgência e emergência à população. Para a análise dos dados, a técnica de análise do conteúdo pelo referencial de Bardin foi utilizada. Resultados: Da análise emergiram três categorias: (a) Sem Trabalho em Equipe não há como realizar as atividades; (b) Treinamento como ferramenta para construção e aprimoramento do Trabalho em Equipe e (c) Motivação: o diferencial está nas pessoas. Conclusões: O Trabalho em Equipe oportuniza transformações na mentalidade e nos métodos laborativos, ocupando um grande e significativo espaço na construção de mecanismos em prol do sucesso organizacional. Para que as transformações necessárias aconteçam, é preciso contar com seres humanos comprometidos, interessados no trabalho e que a organização de saúde invista em treinamento, desenvolvimento de habilidades e educação permanente e/ou continuada, de forma a estimular a participação, a inovação e a criatividade

ENFERMAGEM DO TRABALHO: UMA REVISÃO INTEGRATIVA ACERCA DA ATIVIDADE PROFISSIONAL DO ENFERMEIRO NO PERÍODO PANDEMICO

Occupational nurses play a fundamental role in identifying occupational risks, carrying out medical examinations and educating workers about preventive measures. They also contribute to the analysis of environmental risks, accident prevention, mental health promotion and ergonomic adaptation. During the Covid-19 pandemic, occupational nursing has been crucial in implementing education, prevention and control measures. Objective: to describe the scientific evidence available in national and international literature regarding the professional activity of Occupational Nurses during the Covid-19 pandemic. Method: The methodology adopted was based on extensive research in academic databases, such as PubMed, Scopus and Google Scholar, using relevant keywords related to occupational nursing, occupational health and safety at work. Result: Occupational nursing plays a crucial role in preventing occupational diseases through the identification and control of risks present in work environments, promotion and safety of workers. Discussion: The challenges faced by occupational nursing were observed, such as the lack of adequate resources to carry out their activities effectively, personal protective equipment, limited access to complementary exams and inadequate infrastructure in the workplace. And the need for integration between occupational nursing and other segments of occupational health. Conclusion: Occupational nursing plays a key role in promoting and preserving the health of employees, as well as preventing occupational diseases.La enfermera ocupacional juega un papel fundamental en la identificación de riesgos laborales, la realización de exámenes médicos y la educación de los trabajadores sobre las medidas preventivas. También contribuyen al análisis de riesgos ambientales, la prevención de accidentes, la promoción de la salud mental y la adaptación ergonómica. Durante la pandemia de Covid-19, la enfermería ocupacional ha sido crucial en la implementación de medidas de educación, prevención y control. Objetivo: describir la evidencia científica disponible en la literatura nacional e internacional sobre la actividad profesional de la Enfermería Ocupacional durante la pandemia Covid-19. Método: La metodología adoptada se basó en una extensa investigación en bases de datos académicas, como PubMed, Scopus y Google Scholar, utilizando palabras clave relevantes relacionadas con enfermería ocupacional, salud ocupacional y seguridad en el trabajo. Resultado: La enfermería ocupacional juega un papel crucial en la prevención de enfermedades profesionales a través de la identificación y control de los riesgos presentes en los ambientes laborales, la promoción y la seguridad de los trabajadores. Discusión: Se observaron los desafíos que enfrenta la enfermería ocupacional, como la falta de recursos adecuados para realizar sus actividades de manera efectiva, equipos de protección personal, acceso limitado a exámenes complementarios e infraestructura inadecuada en el lugar de trabajo. Y la necesidad de integración entre la enfermería ocupacional y otros segmentos de la salud ocupacional. Conclusión: La enfermería ocupacional juega un papel clave en la promoción y preservación de la salud de los empleados, así como en la prevención de enfermedades profesionales.Os enfermeiros do trabalho desempenham um  papel fundamental na identificação de riscos ocupacionais, na realização de exames de saúde e na educação dos trabalhadores sobre medidas preventivas. Eles também contribuem para a análise de riscos ambientais, prevenção de acidentes, promoção da saúde mental e adequação ergonômica. Durante a pandemia de Covid-19, a enfermagem do trabalho tem sido crucial na implementação de medidas de educação, prevenção e controle. Objetivo: descrever as evidências científicas disponíveis na literatura nacional e internacional acerca da atividade profissional do Enfermeiro do Trabalho durante a pandemia de Covid-19. Métodos: O método adotado baseou-se em uma ampla pesquisa em bases de dados acadêmicas, como PubMed, Scopus e Google Scholar, utilizando palavras-chave relevantes relacionadas à enfermagem do trabalho, saúde ocupacional e segurança no trabalho. Resultados: A enfermagem do trabalho desempenha um papel crucial na prevenção de doenças ocupacionais por meio da identificação e controle dos riscos presentes nos ambientes de trabalho, promoção e segurança dos trabalhadores. Discussão: Observou-se os desafios enfrentados pela enfermagem do trabalho, como a falta de recursos adequados para realizar suas atividades de forma eficaz, de equipamentos de proteção individual, acesso limitado a exames complementares e infraestrutura inadequada nos locais de trabalho. E a necessidade de integração entre a enfermagem do trabalho e os demais seguimentos da saúde ocupacional. Conclusão: A enfermagem ocupacional exerce um papel primordial na promoção e preservação da saúde dos colaboradores, assim como na prevenção de patologias laborais.Introdução: Os enfermeiros do trabalho desempenham um  papel fundamental na identificação de riscos ocupacionais, na realização de exames de saúde e na educação dos trabalhadores sobre medidas preventivas. Eles também contribuem para a análise de riscos ambientais, prevenção de acidentes, promoção da saúde mental e adequação ergonômica. Durante a pandemia de COVID-19, a enfermagem do trabalho tem sido crucial na implementação de medidas de educação, prevenção e controle. Objetivo: descrever as evidências científicas disponíveis na literatura nacional e internacional acerca da atividade profissional do Enfermeiro do Trabalho durante a pandemia de Covid-19. Métodos: O método adotado baseou-se em uma ampla pesquisa em bases de dados acadêmicas, como PubMed, Scopus e Google Scholar, utilizando palavras-chave relevantes relacionadas à enfermagem do trabalho, saúde ocupacional e segurança no trabalho. Resultados: A enfermagem do trabalho desempenha um papel crucial na prevenção de doenças ocupacionais por meio da identificação e controle dos riscos presentes nos ambientes de trabalho, promoção e segurança dos trabalhadores. Discussão: Observou-se os desafios enfrentados pela enfermagem do trabalho, como a falta de recursos adequados para realizar suas atividades de forma eficaz, de equipamentos de proteção individual, acesso limitado a exames complementares e infraestrutura inadequada nos locais de trabalho. E a necessidade de integração entre a enfermagem do trabalho e os demais seguimentos da saúde ocupacional. Conclusão: A enfermagem ocupacional exerce um papel primordial na promoção e preservação da saúde dos colaboradores, assim como na prevenção de patologias laborais