81 research outputs found

    Ecological and conceptual consequences of Arctic pollution

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    This is the final version. Available on open access from Wiley via the DOI in this recordAlthough the effect of pollution on forest health and decline received much attention in the 1980s, it has not been considered to explain the ‘Divergence Problem’ in dendroclimatology; a decoupling of tree growth from rising air temperatures since the 1970s. Here we use physical and biogeochemical measurements of hundreds of living and dead conifers to reconstruct the impact of heavy industrialisation around Norilsk in northern Siberia. Moreover, we develop a forward model with surface irradiance forcing to quantify long‐distance effects of anthropogenic emissions on the functioning and productivity of Siberia’s taiga. Downwind from the world’s most polluted Arctic region, tree mortality rates of up to 100% have destroyed 24,000 km2 boreal forest since the 1960s, coincident with dramatic increases in atmospheric sulphur, copper, and nickel concentrations. In addition to regional ecosystem devastation, we demonstrate how ‘Arctic Dimming’ can explain the circumpolar ‘Divergence Problem’, and discuss implications on the terrestrial carbon cycle.Forest ServiceMinistry of Science and Higher EducationRussian Science Foundatio

    Percepção de estudantes de psicologia sobre a informática em sua formação profissional

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    Neste artigo analisa-se uma pesquisa de natureza qualitativa, cujo objetivo era explorar a percepção de 45 alunos de psicologia de diferentes universidades da cidade de Santiago do Chile, sobre a incorporação da informática como apoio para a aprendizagem em sua formação profissional. A informação foi coletada através de entrevistas semiestruturadas e analisou-se mediante o processo de codificação da Teoría Fundamentada. Os resultados mostram como categorias principais, o conhecimento da informática, a valoração da informática, e os fatores que obstaculizam o uso desta. Da codificação seletiva se desprende uma alta valoração da informática como ferramenta econômica e cômoda, mas também se observa uma alta reticência dos alunos diante de sua utilização no trabalho profissional tradicional do psicólogo. Encontraram-se fatores pessoais e institucionais nos que se baseia a valoração, a motivação e o nível de conhecimento dos estudantes diante do uso de ferramentas informáticas.This paper analyses a qualitative research aimed to exploring the perception of 45 psychology students from different universities in Santiago de Chile, about incorporating information systems to support learning in their professional training. Data were collected through semi structured interviews and their analysis was based on Grounded Theory's coding process. Results show that the major categories are computer knowledge, appreciation of computers and factors that hinder their use. From the selective coding a positive evaluation emerges of information systems as an economic and useful tool. However, there is also a high reluctance on the part of the students regarding the use of such tools in the psychologist' traditional professional work. Personal and organizational factors were found as bases for students' assessment, motivation and level of knowledge facing the use of these tools.En este artículo se analiza una investigación de naturaleza cualitativa, cuyo objetivo era explorar la percepción de 45 alumnos de psicología de diferentes universidades de la ciudad de Santiago de Chile, sobre la incorporación de la informática como apoyo para el aprendizaje en su formación profesional. La información se recolectó a través de entrevistas semiestructuradas y se analizó mediante el proceso de codificación de la Teoría Fundamentada. Los resultados muestran como categorías principales, el conocimiento de la informática, la valoración de la informática, y los factores que obstaculizan el uso de ésta. De la codificación selectiva se desprende una alta valoración de la informática como herramienta económica y cómoda, pero también se observa una alta reticencia de los alumnos frente a su utilización en el trabajo profesional tradicional del psicólogo. Se encontraron factores personales e institucionales en los cuales se fundamenta la valoración, la motivación y el nivel de conocimiento de los estudiantes frente al uso de herramientas informáticas

    Factors Associated with Colposcopy-Histopathology Confirmed Cervical Intraepithelial Neoplasia among HIV-Infected Women from Rio De Janeiro, Brazil

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    Introduction: Despite the availability of preventive strategies (screening tests and vaccines), cervical cancer continues to impose a significant health burden in low- and medium-resourced countries. HIV-infected women are at increased risk for infection with human papillomavirus (HPV) and thus development of cervical squamous intraepithelial neoplasia (CIN). Methods:Study participants included HIV-infected women enrolling the prospective open cohort of Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation (IPEC/FIOCRUZ). At cohort entry, women were subjected to conventional Papanicolaou test, HPV-DNA test and colposcopy; lesions suspicious for CIN were biopsied. Histopathology report was based on directed biopsy or on specimens obtained by excision of the transformation zone or cervical conization. Poisson regression modeling was used to assess factors associated with CIN2+diagnosis. Results:The median age of the 366 HIV-infected women included in the study was 34 years (interquartile range: 28–41 years). The prevalence of CIN1, CIN2 and CIN3 were 20.0%, 3.5%, and 2.2%, respectively. One woman was found to have cervical cancer. The prevalence of CIN2+was 6.0%. Factors associated with CIN2+diagnosis in the multivariate model were age,years compared to35years(aPR=3.2295CD4Tcellcount,350cells/mm3whencomparedto35 years (aPR = 3.22 95%CI 1.23–8.39), current tobacco use (aPR = 3.69 95%CI 1.54–8.78), nadir CD4 T-cell count,350 cells/mm3 when compared to350 cells/mm3 (aPR = 6.03 95%CI 1.50–24.3) and concomitant diagnosis of vulvar and/or vaginal intraepithelial lesion (aPR = 2.68 95%CI 0.99–7.24). Discussion:Increased survival through wide-spread use of highly active antiretroviral therapy might allow for the development of cervical cancer. In Brazil, limited cytology screening and gynecological care adds further complexity to the HIV-HPV co-infection problem. Integrated HIV care and cervical cancer prevention programs are needed for the prevention of cervical cancer mortality in this group of wome

    Expression of Ovine Herpesvirus -2 Encoded MicroRNAs in an Immortalised Bovine - Cell Line

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    Ovine herpesvirus-2 (OvHV-2) infects most sheep, where it establishes an asymptomatic, latent infection. Infection of susceptible hosts e.g. cattle and deer results in malignant catarrhal fever, a fatal lymphoproliferative disease characterised by uncontrolled lymphocyte proliferation and non MHC restricted cytotoxicity. The same cell populations are infected in both cattle and sheep but only in cattle does virus infection cause dysregulation of cell function leading to disease. The mechanism by which OvHV-2 induces this uncontrolled proliferation is unknown. A number of herpesviruses have been shown to encode microRNAs (miRNAs) that have roles in control of both viral and cellular gene expression. We hypothesised that OvHV-2 encodes miRNAs and that these play a role in pathogenesis. Analysis of massively parallel sequencing data from an OvHV-2 persistently-infected bovine lymphoid cell line (BJ1035) identified forty-five possible virus-encoded miRNAs. We previously confirmed the expression of eight OvHV-2 miRNAs by northern hybridization. In this study we used RT-PCR to confirm the expression of an additional twenty-seven OvHV-2-encoded miRNAs. All thirty-five OvHV-2 miRNAs are expressed from the same virus genome strand and the majority (30) are encoded in an approximately 9 kb region that contains no predicted virus open reading frames. Future identification of the cellular and virus targets of these miRNAs will inform our understanding of MCF pathogenesis
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