5,742 research outputs found

    Detection of neutral hydrogen in early-type dwarf galaxies of the Sculptor Group

    Full text link
    We present our results of deep 21 cm line (HI) observations of five early and mixed-type dwarf galaxies in the nearby Sculptor group using the ATNF 64m Parkes Radio Telescope. Four of these objects, ESO294-G010, ESO410-G005, ESO540-G030, and ESO540-G032, were detected in HI with neutral hydrogen masses in the range of 2-9x10^5 M_{\odot} (MHI/LBM_{HI}/L_{B} = 0.08, 0.13, 0.16, and 0.18, respectively). These HI masses are consistent with the gas mass expected from stellar outflows over a large period of time. Higher resolution radio data from the Australia Telescope Compact Array were further analysed to measure more accurate positions and the distribution of the HI gas. In the cases of dwarfs ESO294-G010 and ESO540-G030, we find significant offsets of 290 pc and 460 pc, respectively, between the position of the HI peak flux and the center of the stellar component. These offsets are likely to have internal cause such as the winds from star-forming regions. The fifth object, the spatially isolated dwarf elliptical Scl-dE1, remains undetected at our 3\sigma limit of 22.5 mJy km/s and thus must contain less than 10^5 M_{\odot} of neutral hydrogen. This leaves Scl-dE1 as the only Sculptor group galaxy known where no interstellar medium has been found to date. The object joins a list of similar systems including the Local Group dwarfs Tucana and Cetus that do not fit into the global picture of the morphology-density relation where gas-rich dwarf irregulars are in relative isolation and gas-deficient dwarf ellipticals are satellites of more luminous galaxies.Comment: 21 pages, 4 figures, to be published in AJ (accepted

    Interstellar medium disruption in the Centaurus A group

    Full text link
    We present the results of a 21 cm neutral hydrogen (HI) line detection experiment in the direction of 18 low luminosity dwarf galaxies of the Centaurus A group, using the Australia Telescope National Facility 64m Parkes Radio Telescope and the Australia Telescope Compact Array. Five dwarfs have HI masses between M_HI=4x10^5 to M_HI=2.1x10^7 Msol and 0.04<M_HI/L_B<1.81 Msol L_{sol, B}^-1. The other 13 have upper-limits between M_HI<5x10^5 and M_HI<4x10^6 Msol (M_HI}/L_B<0.24 Msol L_{sol, B}^-1). Two of the mixed-morphology dwarfs remain undetected in HI, a situation that is in contrast to that of similar Local Group and Sculptor group objects where all contain significant amounts of neutral gas. There is a discontinuity in the HI properties of Centaurus A group low luminosity dwarfs that is unobserved amongst Sculptor group dwarfs. All objects fainter than M_B=-13 have either M_HI>10^7 Msol or M_HI<10^6 Msol. This gap may be explained by the ram pressure stripping mechanism at work in this dense environment where all galaxies with M_HI<10^7 Msol have been stripped of their gas. The required intergalactic medium density to achieve this is ~10^-3 cm^-3.Comment: 7 figures, 2 table

    Recurrent pregnancy loss is associated with a pro-senescent decidual response during the peri-implantation window

    Get PDF
    During the implantation window, the endometrium becomes poised to transition to a pregnant state, a process driven by differentiation of stromal cells into decidual cells (DC). Perturbations in this process, termed decidualization, leads to breakdown of the feto-maternal interface and miscarriage, but the underlying mechanisms are poorly understood. Here, we reconstructed the decidual pathway at single-cell level in vitro and demonstrate that stromal cells first mount an acute stress response before emerging as DC or senescent DC (snDC). In the absence of immune cell-mediated clearance of snDC, secondary senescence transforms DC into progesterone-resistant cells that abundantly express extracellular matrix remodelling factors. Additional single-cell analysis of midluteal endometrium identified DIO2 and SCARA5 as marker genes of a diverging decidual response in vivo. Finally, we report a conspicuous link between a pro-senescent decidual response in peri-implantation endometrium and recurrent pregnancy loss, suggesting that pre-pregnancy screening and intervention may reduce the burden of miscarriage

    Overlapping Dopaminergic Pathway Genetic Susceptibility to Heroin and Cocaine Addictions in African Americans

    Get PDF
    Drugs of abuse activate the mesolimbic dopaminergic pathway. Genetic variations in the dopaminergic system may contribute to drug addiction. Several processes are shared between cocaine and heroin addictions but some neurobiological mechanisms may be specific. This study examined the association of 98 single nucleotide polymorphisms in 13 dopamine-related genes with heroin addiction (OD) and/or cocaine addiction (CD) in a sample of 801 African Americans (315 subjects with OD +/- CD, 279 subjects with CD, and 207 controls). Single-marker analyses provided nominally significant evidence for associations of 24 SNPs) in DRD1, ANKK1/DRD2, DRD3, DRD5, DBH, DDC, COMT and CSNK1E. A DRD2 7-SNPs haplotype that includes SNPs rs1075650 and rs2283265, which were shown to alter D2S/D2L splicing, was indicated in both addictions. The Met allele of the functional COMT Val158Met was associated with protection from OD. None of the signals remained significant after correction for multiple testing. The study results are in accordance with the results of previous studies, including our report of association of DRD1 SNP rs5326 with OD. The findings suggest the presence of an overlap in genetic susceptibility for OD and CD, as well as shared and distinct susceptibility for OD in subjects of African and European descent

    UM ESTUDO SOBRE A INTERAÇÃO ENTRE A PESQUISA CIENTÍFICA E A PRÁTICA PROFISSIONAL CONTÁBIL

    Get PDF
    The aim of this study was to analyze the interaction between scientific research and professional accounting practice. In this exploratory study, as it examines a theme that has been little explored in Brazil, a quantitative approach was adopted and a survey was used as the data collection technique, supported by a research instrument with questions on aspects like: interest in and use of research; study and development of themes; means to disseminate the research; and causes of the gap between research and practice. Considering the objectives, it is classified as descriptive, since it was described how this interaction occurs. Data were analyze through factor analysis in R, resuming them in factors for further analysis, validated through the Kaiser-Meyer-Olkin (KMO) test and Bartlett’s sphericity yet. In conclusion, due to their different characteristics, it is natural that some distancing exists between research and accounting practice. This can be minimized though, among other factors, through professionals’ great interest in knowing and applying the research results in practice, and also by confirming that the most researched themes in accountancy are the themes of greatest interest in accounting professionals’ opinion. These results suggest that greater attention is due to the interaction and communication between the academy and accounting professionals, with a view to greater efficacy.Este estudio tuvo por objetivo analizar la interacción de la pesquisa científica con la práctica de la profesión contable. Se trata de un estudio exploratorio, por dedicarse a examinar un tema poco explotado en el Brasil, con abordaje cuantitativo y utilización de survey como técnica de colecta de los datos, apoyada por un instrumento de pesquisa conteniendo cuestiones que abordaron aspectos como: interés y utilización de las pesquisas; estudio y desarrollo de temas; medios de divulgación de la pesquisa; y causas de la laguna entre la pesquisa y la práctica. Es classificado en relación a los objetivos como descriptivo, en la medida en que se describió como se da esta interacción. Los datos fueron analizados mediante la técnica estadística de análisis factorial del tipo R, resumiéndolos en factores para el posterior análisis, validados por medio de los testes Kaiser-Meyer-Olkin (KMO) y Bartlett de esferacidad. Se concluyó que, en razón de las diferentes naturalezas, es natural cierto distanciamiento entre la pesquisa y la práctica contable. No obstante, ése puede ser minimizado, entre otros factores, por el gran interés de los profesionales en conocer y aplicar los resultados de pesquisas en la práctica, y, también, por la confirmación de que los temas más pesquisados en el área contable corresponden a los temas de mayor interés en la opinión de los profesionales Contables. Tales resultados sugieren que la interacción y la comunicación entre la academia y los profesionales contabilistas deban merecer mayor atención visando tornarlas más eficaces.Este estudo teve por objetivo analisar a interação da pesquisa científica com a prática da profissão contábil. Trata-se de um estudo exploratório, por se dedicar a examinar um tema pouco explorado no Brasil, com abordagem quantitativa e utilização de survey como técnica de coleta dos dados, apoiada por um instrumento de pesquisa contendo questões que abordaram aspectos como: interesse e utilização das pesquisas; estudo e desenvolvimento de temas; meios de divulgação da pesquisa; e causas da lacuna entre a pesquisa e a prática. É classificado quanto aos objetivos como descritivo, na medida em que se descreveu como se dá esta interação. Os dados foram analisados mediante a técnica estatística de análise fatorial do tipo R, resumindo-os em fatores para a posterior análise, validados por meio dos testes Kaiser-Meyer-Olkin (KMO) e Bartlett de esferacidade. Concluiu-se que, em razão das diferentes naturezas, é natural certo distanciamento entre a pesquisa e a prática contábil. No entanto, esse pode ser minimizado, entre outros fatores, pelo grande interesse dos profissionais em conhecer e aplicar os resultados de pesquisas na prática, e, ainda, pela confirmação de que os temas mais pesquisados na área contábil correspondem aos temas de maior interesse na opinião dos profissionais contábeis. Tais resultados sugerem que a interação e a comunicação entre a academia e os profissionais contabilistas devam merecer maior atenção visando torná-las mais eficazes

    ;;Validação da fita "CIMDER de 3 cores" como instrumento de detecção de risco nutricional entre pré-escolares

    Get PDF
    The value of the use, by the health agents in Rondônia, Brazil, of the nutritional classification proposed by the Multidisciplinary Research Center for Rural Development (CIMDER), Colombia, known as the three color CIMDER band, is analyzed. The band, used to measure arm circumference, would be used as an instrument for the detection of nutritional risk in children under five years of age and for refering them to larger, more complex, health units. For this purpose, a sample of 1,268 children were studied. The results of the nutritional classification obtained by the band and the results of Gomez classification were compared. The application of the validations tests resulted in the following values: sensibility = 77.1%; specificity = 68.8%; positive predictive value = 59.0%; negative predictive value = 83.7%; rate of false positives = 31.2% and rate of false negatives = 22.9%. Except for the rate of false positives, the rest of the results were considered to be satisfactory, sufficiently so to recommend the use of the CIMDER band as an instrument of selection by the health agents in Rondônia. More specific indicators should be adopted at the larger, more complex health units, with a view to reducing the number of false positives in the programs for attendance to the undernourished.Analisou-se a validade da utilização da fita "CIMDER de 3 cores" pelos agentes de saúde do Estado de Rondônia, Brasil, como instrumento de detecção de risco nutricional entre crianças menores de 5 anos, para fins de encaminhamento para controle em unidades de maior complexidade que o posto de saúde. De uma amostra composta por 1.268 crianças, compararam-se os resultados da classificação nutricional obtida pela fita e da resultante da classificação de Gomez. A aplicação dos testes de validação resultou nos seguintes valores: sensibilidade = 77,1 %; especificidade = 68,8%; valor prPolonoroeste) editivo positivo = 59,0%; valor preditivo negativo = 83,7%; taxa de falsos positivos = 31,2%; taxa de falsos negativos = 22,9. Excetuando a taxa de falsos positivos, os demais resultados foram considerados suficientemente satisfatórios para que se recomende o uso da fita CIMDER como instrumento de triagem pelos agentes de saúde de Rondônia. Outros indicadores mais específicos deverão ser adotados em nível das unidades de saúde de maior complexidade para reduzir o número de falsos positivos nos programas de assistência dirigidos aos desnutridos
    corecore