Effects of Star Formation Stochasticity on the Ly-alpha & Lyman Continuum Emission from Dwarf Galaxies during Reionization

Observations of distant galaxies play a key role in improving our understanding of the Epoch of Reionization (EoR). The observed Ly-alpha emission line strength - quantified by its restframe equivalent width (EW) - provides a valuable diagnostic of stellar populations and dust in galaxies during and after the EoR. In this paper we quantify the effects of star formation stochasticity on the predicted Ly-alpha EW in dwarf galaxies, using the publicly available code SLUG ('Stochastically Light Up Galaxies'). We compute the number of hydrogen ionizing photons, as well as flux in the Far UV for a set of models with star formation rates (SFR) in the range 10-3-1 Msol/yr. From these fluxes we compute the luminosity, L-alpha, and the EW of the Ly-alpha line. We find that stochasticity alone induces a broad distribution in L-alpha and EW at a fixed SFR, and that the widths of these distributions decrease with increasing SFR. We parameterize the EW probability density function (PDF) as an SFR-dependent double power law. We find that it is possible to have EW as low as ~EW0/4 and as high as ~3 times the EW0, where EW0 denotes the expected EW in the absence of stochasticity. We argue that stochasticity may therefore be important when linking drop-out and narrow-band selected galaxies, when identifying population III galaxies, and that it may help to explain the large EW (EW > 100 - 200 A) observed for a fraction of Ly-alpha- selected galaxies. Finally, we show that stochasticity can also affect the inferred escape fraction of ionizing photons from galaxies. In particular, we argue that stochasticity may simultaneously explain the observed anomalous ratios of the Lyman continuum flux density to the (non-ionizing) UV continuum density in so-called Lyman-Bump galaxies at z = 3.1, as well as the absence of such objects among a sample of z = 1.3 drop-out galaxies.Comment: 9 pages, 4 figures, accepted for publication in MNRA

DEFICIÊNCIAS NUTRICIONAIS DE VITAMINAS E MINERAIS EM PACIENTES PÓS- BARIÁTRICOS: REVISÃO BIBLIOGRÁFICA

Bariatric surgery is one of the treatments used in patients with obesity, with requirements to be followed for scientifically supported techniques aimed at treating morbid or severe obesity and chronic diseases related to excess body fat. The changes that occur in the gastrointestinal tract resulting from bariatric surgery affect the absorption of micronutrients, leading to nutritional deficiencies such as vitamin B12, B1, C, folate, A, D, E and K, along with the minerals iron, selenium, zinc and copper. Bibliographical review study with the objective of correcting the main vitamin and mineral deficiencies that affect post-bariatric patients during the weight loss process, seeking to identify the most effective treatment for recovering the patient's nutritional health. clinical studies published from 2018 to 2023, in databases such as Scielo, Pubmed, and Google Scholar, using the following descriptors: 'Bariatrica', 'Micronutrients', 'Supplementation'. The data clearly shows deficiencies in minerals such as iron, zinc, selenium, calcium, and vitamins such as B12, folic acid, D, B1 and E were observed in research and persist beyond the first year after bariatric surgery, making supplementation essential. and monitoring serum levels as recommended by the American Society for Metabolic and Bariatric Surgery.      La cirugía bariátrica es uno de los tratamientos utilizados en pacientes con obesidad, requiriendo criterios a seguir para las técnicas avaladas científicamente dirigidas al tratamiento de la obesidad mórbida o severa y las enfermedades crónicas relacionadas con el exceso de grasa corporal. Los cambios que se producen en el tracto gastrointestinal debido a la cirugía bariátrica afectan a la absorción de micronutrientes, lo que conlleva deficiencias nutricionales como la vitamina B12, B1, C, ácido fólico, A, D, E y K, junto con los minerales hierro, selenio, zinc y cobre. Se trata de una revisión bibliográfica dirigida a discutir las principales deficiencias de vitaminas y minerales que afectan a los pacientes post-bariátricos durante el proceso de pérdida de peso, buscando identificar el tratamiento más efectivo para la recuperación de la salud nutricional del paciente. La búsqueda bibliográfica investigó los resultados de estudios clínicos publicados en el período de 2018 a 2023, en bases de datos como Scielo, Pubmed y Google Scholar, utilizando los siguientes descriptores: 'Bariátrico', 'Micronutrientes', 'Suplementación'. Los datos muestran claramente las deficiencias de minerales como hierro, zinc, selenio, calcio y vitaminas como B12, ácido fólico, D, B1 y E que fueron observadas por la investigación y que persisten más allá del primer año después de la cirugía bariátrica, por lo que la suplementación y el monitoreo de los niveles séricos son esenciales según lo recomendado por la Sociedad Americana de Cirugía Metabólica y Bariátrica.  A cirurgia bariátrica é um dos tratamentos utilizados em pacientes com obesidade, exigindo critérios a serem seguidos para a técnica, com respaldo científico, direcionadas ao tratamento da obesidade mórbida ou grave e de doenças crônicas relacionadas ao excesso de gordura corporal. As modificações ocorridas no trato gastrointestinal decorrentes da cirurgia bariátrica, afetam a absorção de micronutrientes, levando a deficiências nutricionais como vitamina B12, B1, C, folato, A, D, E e K, juntamente com os minerais ferro, selênio, zinco e cobre. Estudo de revisão bibliográfica com objetivo de discorrer sobre as principais deficiências de vitaminas e minerais que afetam os pacientes pós-bariátricos durante o processo de emagrecimento, buscando identificar o tratamento mais eficaz para a recuperação da saúde nutricional do paciente. A pesquisa bibliográfica investigou os resultados de estudos clínicos publicados no período de 2018 a 2023, nas bases de dados como Scielo, Pubmed, e Google Scholar, usando os seguintes descritores: ‘Bariátrica’, ‘Micronutrientes’, ‘Suplementação’. Os dados analisados mostram as deficiências de minerais como: ferro, zinco, selênio, cálcio, e as vitaminas como B12, ácido fólico, D, B1 e E. e que persistem além do primeiro ano após a bariátrica, tornando essencial a suplementação e acompanhamento dos níveis séricos conforme a recomendação da American Society for Metabolic and Bariatric Surgery.  A cirurgia bariátrica é um dos tratamentos utilizados em pacientes com obesidade, exigindo critérios a serem seguidos para a técnica, com respaldo científico, direcionadas ao tratamento da obesidade mórbida ou grave e de doenças crônicas relacionadas ao excesso de gordura corporal. As modificações ocorridas no trato gastrointestinal decorrentes da cirurgia bariátrica, afetam a absorção de micronutrientes, levando a deficiências nutricionais como vitamina B12, B1, C, folato, A, D, E e K, juntamente com os minerais ferro, selênio, zinco e cobre. Estudo de revisão bibliográfica com objetivo de discorrer sobre as principais deficiências de vitaminas e minerais que afetam os pacientes pós-bariátricos durante o processo de emagrecimento, buscando identificar o tratamento mais eficaz para a recuperação da saúde nutricional do paciente. A pesquisa bibliográfica investigou os resultados de estudos clínicos publicados no período de 2018 a 2023, nas bases de dados como Scielo, Pubmed, e Google Scholar, usando os seguintes descritores: ‘Bariátrica’, ‘Micronutrientes’, ‘Suplementação’. Os dados analisados mostram as deficiências de minerais como: ferro, zinco, selênio, cálcio, e as vitaminas como B12, ácido fólico, D, B1 e E. e que persistem além do primeiro ano após a bariátrica, tornando essencial a suplementação e acompanhamento dos níveis séricos conforme a recomendação da American Society for Metabolic and Bariatric Surgery.

The MUSIC of Galaxy Clusters I: Baryon properties and Scaling Relations of the thermal Sunyaev-Zel'dovich Effect

We introduce the Marenostrum-MultiDark SImulations of galaxy Clusters (MUSIC) Dataset, one of the largest sample of hydrodynamically simulated galaxy clusters with more than 500 clusters and 2000 groups. The objects have been selected from two large N-body simulations and have been resimulated at high resolution using SPH together with relevant physical processes (cooling, UV photoionization, star formation and different feedback processes). We focus on the analysis of the baryon content (gas and star) of clusters in the MUSIC dataset both as a function of aperture radius and redshift. The results from our simulations are compared with the most recent observational estimates of the gas fraction in galaxy clusters at different overdensity radii. When the effects of cooling and stellar feedbacks are included, the MUSIC clusters show a good agreement with the most recent observed gas fractions quoted in the literature. A clear dependence of the gas fractions with the total cluster mass is also evident. The impact of the aperture radius choice, when comparing integrated quantities at different redshifts, is tested: the standard definition of radius at a fixed overdensity with respect to critical density is compared with a definition based on the redshift dependent overdensity with respect to background density. We also present a detailed analysis of the scaling relations of the thermal SZ (Sunyaev Zel'dovich) Effect derived from MUSIC clusters. The integrated SZ brightness, Y, is related to the cluster total mass, M, as well as, the M-Y counterpart, more suitable for observational applications. Both laws are consistent with predictions from the self-similar model, showing a very low scatter. The effects of the gas fraction on the Y-M scaling and the presence of a possible redshift dependence on the Y-M scaling relation are also explored.Comment: 22 pages, 25 figures, accepted for pubblication by MNRA

Sp1-regulated expression of p11 contributes to motor neuron degeneration by membrane insertion of TASK1

Disruption in membrane excitability contributes to malfunction and differential vulnerability of specific neuronal subpopulations in a number of neurological diseases. The adaptor protein p11, and background potassium channel TASK1, have overlapping distributions in the CNS. Here, we report that the transcription factor Sp1 controls p11 expression, which impacts on excitability by hampering functional expression of TASK1. In the SOD1-G93A mouse model of ALS, Sp1-p11-TASK1 dysregulation contributes to increased excitability and vulnerability of motor neurons. Interference with either Sp1 or p11 is neuroprotective, delaying neuron loss and prolonging lifespan in this model. Nitrosative stress, a potential factor in human neurodegeneration, stimulated Sp1 expression and human p11 promoter activity, at least in part, through a Sp1-binding site. Disruption of Sp1 or p11 also has neuroprotective effects in a traumatic model of motor neuron degeneration. Together our work suggests the Sp1-p11- TASK1 pathway is a potential target for treatment of degeneration of motor neurons

Comparative descriptions of eggs from three species of Rhodnius (Hemiptera: Reduviidae: Triatominae)

The authors describe and compare the morphological and ultrastructural characteristics of eggs from the three most recent described species of the genus Rhodnius Stål, 1859, which have not previously been studied. These species are Rhodnius colombiensis (Mejia, Galvão & Jurberg 1999), Rhodnius milesi (Carcavallo, Rocha, Galvão & Jurberg 2001) and Rhodnius stali (Lent, Jurberg & Galvão 1993). The results revealed that there are similarities in the exochorial architecture of optical microscopy and scanning electron microscopy; these include the predominance of hexagonal cells that are common to all Rhodnius species and variable degrees of lateral flattening, which is common not only to species of this genus, but also to the Rhodniini tribe. Differences in overall colour, the presence of a collar in R. milesi, a longitudinal bevel in R. stali and the precise length of R. colombiensis can be useful distinguishing features. As a result of this study, the key for egg identification proposed by Barata in 1981 can be updated.European Community - Chagas Disease Intervention ActivitiesCNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES

Intentional injury reported by young people in the Federated States of Micronesia, Kingdom of Tonga and Vanuatu

<p>Abstract</p> <p>Background</p> <p>Intentional injury presents a threat to the physical and psychological well being of young people, especially in developing countries, which carry the greatest part of the global injury burden. While the importance of this problem is recognized, there are limited population data in low and middle income countries that can guide public health action. The present study investigates the prevalence and distribution of intentional injury among young people in three Pacific Island societies, and examines behavioural and psychosocial factors related to risk of intentional injury.</p> <p>Methods</p> <p>Population surveys were conducted with <b>s</b>tudents aged 11–17 years in Pohnpei State in the Federated States of Micronesia (n = 1495), the Kingdom of Tonga (n = 2808) and Vanuatu (n = 4474). Surveys measured self-reported injury and intentional injury, sources of intentional injury, and the range of behavioural, psychological, educational and social variables that may be related to injury risk.</p> <p>Results</p> <p>Among boys and girls aged 14–17 years the respective period prevalence of intentional injury was 62% and 56% in Pohnpei, 58% and 41% in Tonga, and 33% and 24% in Vanuatu. The prevalence of intentional injury declined with age in Tonga and Vanuatu, but there was little evidence of an age-trend in Pohnpei. Across the three societies, the major sources of intentional injury among boys were 'other persons' followed by boyfriends/girlfriends and fathers. Mothers, boyfriends/girlfriends and other persons were primary sources of injury among girls. An intentional injury was reported more often by those who had been bullied (OR 1.40–1.66, P < 0.05), by regular smokers in Tonga and Vanuatu (OR 1.52–2.21, P < 0.05), and illicit drug users in Pohnpei and Vanuatu (OR 1.87–1.92, P < 0.05).</p> <p>Conclusion</p> <p>Intentional injury was reported extensively in these three populations. Interventions directed towards the school environment and which take into account the role of bullying and drug use need to be considered.</p

Association of Impulsivity and Polymorphic MicroRNA-641 Target Sites in the SNAP-25 Gene.

Impulsivity is a personality trait of high impact and is connected with several types of maladaptive behavior and psychiatric diseases, such as attention deficit hyperactivity disorder, alcohol and drug abuse, as well as pathological gambling and mood disorders. Polymorphic variants of the SNAP-25 gene emerged as putative genetic components of impulsivity, as SNAP-25 protein plays an important role in the central nervous system, and its SNPs are associated with several psychiatric disorders. In this study we aimed to investigate if polymorphisms in the regulatory regions of the SNAP-25 gene are in association with normal variability of impulsivity. Genotypes and haplotypes of two polymorphisms in the promoter (rs6077690 and rs6039769) and two SNPs in the 3' UTR (rs3746544 and rs1051312) of the SNAP-25 gene were determined in a healthy Hungarian population (N = 901) using PCR-RFLP or real-time PCR in combination with sequence specific probes. Significant association was found between the T-T 3' UTR haplotype and impulsivity, whereas no association could be detected with genotypes or haplotypes of the promoter loci. According to sequence alignment, the polymorphisms in the 3' UTR of the gene alter the binding site of microRNA-641, which was analyzed by luciferase reporter system. It was observed that haplotypes altering one or two nucleotides in the binding site of the seed region of microRNA-641 significantly increased the amount of generated protein in vitro. These findings support the role of polymorphic SNAP-25 variants both at psychogenetic and molecular biological levels

MIR137 is the key gene mediator of the syndromic obesity phenotype of patients with 1p21.3 microdeletions.

BACKGROUND: Deletions in the long arm of chromosome 1 have been described in patients with a phenotype consisting primarily of obesity, intellectual disability and autism-spectrum disorder. The minimal region of overlap comprises two genes: DPYD and MIR137. CASE PRESENTATION: We describe a 10-year-old boy with syndromic obesity who carries a novel 1p21.3 deletion overlapping the critical region with the MIR137 gene only. CONCLUSIONS: This study suggests that MIR137 is the mediator of the obesity phenotype of patients carrying 1p21.3 microdeletions