New developments in the analysis of column-collapse pyroclastic density currents through numerical simulations of multiphase flows

Abstract. A granular multiphase model has been used to evaluate the action of differently sized particles on the dynamics of fountains and associated pyroclastic density currents. The model takes into account the overall disequilibrium conditions between a gas phase and several solid phases, each characterized by its own physical properties. The dynamics of the granular flows (fountains and pyroclastic density currents) has been simulated by adopting a Reynolds-averaged Navier-Stokes model for describing the turbulence effects. Numerical simulations have been carried out by using different values for the eruptive column temperature at the vent, solid particle frictional concentration, turbulent kinetic energy, and dissipation. The results obtained provide evidence of the multiphase nature of the model and describe several disequilibrium effects. The low concentration (≤5 × 10−4) zones lie in the upper part of the granular flow, above the fountain, and above the tail and body of pyroclastic density current as thermal plumes. The high concentration zones, on the contrary, lie in the fountain and at the base of the current. Hence, pyroclastic density currents are assimilated to granular flows constituted by a low concentration suspension flowing above a high concentration basal layer (boundary layer), from the proximal regions to the distal ones. Interactions among the solid particles in the boundary layer of the granular flow are controlled by collisions between particles, whereas the dispersal of particles in the suspension is determined by the dragging of the gas phase. The simulations describe well the dynamics of a tractive boundary layer leading to the formation of stratified facies during Strombolian to Plinian eruptions

Os Mitos de Estupro e a (im)parcialidade Jurídica: A Percepção de Estudantes de Direito sobre Mulheres Vítimas de Violência Sexual

Compreendidos enquanto um complexo conjunto de crenças que culpam a vítima, absolvem o agressor e minimizam e/ou justificam a agressão contra as mulheres, os mitos de estupro servem para sustentar e perpetuar este tipo de violência. Pesquisas no âmbito da violência sexual vêm, ao longo dos anos, chamando cada vez mais a atenção para a gravidade e relevância deste tema e fazendo com que pesquisadores se questionem acerca de quais fatores estão envolvidos nesta temática. Estes estudos têm proporcionado maior visibilidade à questão, entretanto, ainda são muitas as lacunas na literatura sobre o tema, principalmente com relação aos aspectos culturais que dão sustentação a discursos de responsabilização das vítimas, perpetuação e banalização da violência por parte dos profissionais da área jurídica. Tendo como base as teorias de Representação Social, Valores Humanos e Honra, esta dissertação objetivou, primordialmente, verificar e compreender quais são os construtos que servem de sustentação para a manutenção e propagação dos mitos de estupro no contexto acadêmico jurídico. Para tanto, uma pesquisa foi realizada com 281 estudantes do último ano do curso de Direito, sendo 57,6% do sexo feminino, com média de idade de 23,6 anos (DP = 3,78). Estes participantes responderam um questionário contendo instrumentos padronizados (Honra, Mitos de Estupro, Desejabilidade Social e Valores Humanos), evocações, uma pergunta aberta e, ainda, questões sociodemográficas. Para apresentar o embasamento teórico e os resultados da pesquisa de forma estruturada, a dissertação está dividida em três artigos. O primeiro artigo apresenta a validação da Escala de Mitos de Estupro, assim como a associação das dimensões encontradas com a desejabilidade social, o sexo e o nível de religiosidade dos participantes. O segundo artigo, por sua vez, apresenta as associações observadas entre as dimensões de Mitos de Estupro, os valores humanos e a preocupação com a honra. Por fim, o terceiro artigo, buscou identificar, através de evocações livres e uma pergunta aberta, as representações de mulher, honra e desonra feminina e quais argumentos são utilizados na defesa de um acusado de violência sexual. Os dados foram organizados e analisados mediante o uso dos softwares Evoc e SPSS 19, sendo também utilizada Análise de Conteúdo. Em geral, foram observadas associações entre a aceitação dos mitos de estupro, valores, honra e o nível de religiosidade, corroborando as associações teóricas esperadas. As representações sociais sobre o tema apontam para a existência, no discurso de estudantes de Direito, de uma contradição entre os ditos ideais de justiça‟ e imparcialidade‟ e práticas que produzem e validam preconceitos, injustiças e opressão a mulheres vítimas de estupro. Com base nos achados desta pesquisa, defende-se a necessidade de um debate aprofundado acerca da formação destes que serão futuros operadores do Direito e terão que lidar, em algum grau, com os personagens envolvidos neste tipo de crime. Palavras-chave: Direito, Honra, Mitos de estupro, Representação Social, Valores Humanos

Avaliação da fertilidade real e da capacidade mais provável de fertilidade real de matrizes de um rebanho da Raça Nelore.

Análise de 1146 matrizes Nelore de um rebanho criado no Oeste do Estado de São Paulo.Resumo expandido

MicroRNA expression profiles in pediatric dysembryoplastic neuroepithelial tumors.

© Springer Science+Business Media New York 2015Among noncoding RNAs, microRNAs (miRNAs) have been most extensively studied, and their biology has repeatedly been proven critical for central nervous system pathological conditions. The diagnostic value of several miRNAs was appraised in pediatric dysembryoplastic neuroepithelial tumors (DNETs) using miRNA microarrays and receiving operating characteristic curves analyses. Overall, five pediatric DNETs were studied. As controls, 17 samples were used: the FirstChoice Human Brain Reference RNA and 16 samples from deceased children who underwent autopsy and were not present with any brain malignancy. The miRNA extraction was carried out using the mirVANA miRNA Isolation Kit, while the experimental approach included miRNA microarrays covering 1211 miRNAs. Quantitative real-time polymerase chain reaction was performed to validate the expression profiles of miR-1909* and miR-3138 in all samples initially screened with miRNA microarrays. Our findings indicated that miR-3138 might act as a tumor suppressor gene when down-regulated and miR-1909* as a putative oncogenic molecule when up-regulated in pediatric DNETs compared to the control cohort. Subsequently, both miRNA signatures might serve as putative diagnostic biomarkers for pediatric DNETs.Peer reviewedFinal Accepted Versio

The antenatal causes of cerebral palsy - Genetic and viral associations

Cerebral palsy is the most common neurological disorder in children. Epidemiological evidence suggests that antenatal origins are a major cause. Currently there is no antenatal test for cerebral palsy, no proven preventable measures in late pregnancy, and no known cure. Cerebral palsy affects not only the diagnosed child, but also their family and the community, requiring considerable social and financial resources to assist these children in their daily lives.Catherine S. Gibson, Alastair H. MacLennan, Paul N. Goldwater, and Gustaaf A. Dekker for The South Australian Cerebral Palsy Research Grou

Intratumoral heterogeneity of microRNA expression in rectal cancer

Introduction: An increasing number of studies have investigated microRNAs (miRNAs) as potential markers of diagnosis, treatment and prognosis. So far, agreement between studies has been minimal, which may in part be explained by intratumoral heterogeneity of miRNA expression. The aim of the present study was to assess the heterogeneity of a panel of selected miRNAs in rectal cancer, using two different technical approaches. Materials and Methods: The expression of the investigated miRNAs was analysed by real-time quantitative polymerase chain reaction (RT-qPCR) and in situ hybridization (ISH) in tumour specimens from 27 patients with T3-4 rectal cancer. From each tumour, tissue from three different luminal localisations was examined. Inter- and intra-patient variability was assessed by calculating intraclass correlation coefficients (ICCs). Correlations between RT-qPCR and ISH were evaluated using Spearman's correlation. Results: ICCsingle (one sample from each patient) was higher than 50% for miRNA-21 and miRNA-31. For miRNA-125b, miRNA-145, and miRNA-630, ICCsingle was lower than 50%. The ICCmean (mean of three samples from each patient) was higher than 50% for miRNA-21(RT-qPCR and ISH), miRNA-125b (RT-qPCR and ISH), miRNA-145 (ISH), miRNA-630 (RT-qPCR), and miRNA-31 (RT-qPCR). For miRNA-145 (RT-qPCR) and miRNA-630 (ISH), ICCmean was lower than 50%. Spearman correlation coefficients, comparing results obtained by RT-qPCR and ISH, respectively, ranged from 0.084 to 0.325 for the mean value from each patient, and from -0.085 to 0.515 in the section including the deepest part of the tumour. Conclusion: Intratumoral heterogeneity may influence the measurement of miRNA expression and consequently the number of samples needed for representative estimates. Our findings with two different methods suggest that one sample is sufficient for adequate assessment of miRNA-21 and miRNA-31, whereas more samples would improve the assessment of miRNA-125b, miRNA-145, and miRNA-630. Interestingly, we found a poor correlation between the expression estimates obtained by RT-qPCR and ISH, respectively

Expression Profiling of Rectal Tumors Defines Response to Neoadjuvant Treatment Related Genes

To date, no effective method exists that predicts the response to preoperative chemoradiation (CRT) in locally advanced rectal cancer (LARC). Nevertheless, identification of patients who have a higher likelihood of responding to preoperative CRT could be crucial in decreasing treatment morbidity and avoiding expensive and time-consuming treatments. The aim of this study was to identify signatures or molecular markers related to response to pre-operative CRT in LARC. We analyzed the gene expression profiles of 26 pre-treatment biopsies of LARC (10 responders and 16 non-responders) without metastasis using Human WG CodeLink microarray platform. Two hundred and fifty seven genes were differentially over-expressed in the responder patient subgroup. Ingenuity Pathway Analysis revealed a significant ratio of differentially expressed genes related to cancer, cellular growth and proliferation pathways, and c-Myc network. We demonstrated that high Gng4, c-Myc, Pola1, and Rrm1 mRNA expression levels was a significant prognostic factor for response to treatment in LARC patients (p<0.05). Using this gene set, we were able to establish a new model for predicting the response to CRT in rectal cancer with a sensitivity of 60% and 100% specificity. Our results reflect the value of gene expression profiling to gain insight about the molecular pathways involved in the response to treatment of LARC patients. These findings could be clinically relevant and support the use of mRNA levels when aiming to identify patients who respond to CRT therapy.C, CC and AB were supported by projects CTS2200 and PI-0710-2013 of Junta de Andalucía, TIN2013-41990-R of Programa Estatal I+D+i MINECO, and GREIB PYR_2010-02 and 2010_05 of University of Granada