257 research outputs found

    Promiscuity and the Evolution of Sexual Transmitted Diseases

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    We study the relation between different social behaviors and the onset of epidemics in a model for the dynamics of sexual transmitted diseases. The model considers the society as a system of individual sexuated agents that can be organized in couples and interact with each other. The different social behaviors are incorporated assigning what we call a promiscuity value to each individual agent. The individual promiscuity is taken from a distributions and represents the daily probability of going out to look for a sexual partner, abandoning its eventual mate. In terms of this parameter we find a threshold for the epidemic which is much lower than the classical fully mixed model prediction, i.e. R0R_0 (basic reproductive number) =1= 1. Different forms for the distribution of the population promiscuity are considered showing that the threshold is weakly sensitive to them. We study the homosexual and the heterosexual case as well.Comment: 6 pages, 4 figure

    The Action Research as a Methodology in the Construction of the Municipal Geographic School Atlas of Conceição de Macabu/RJ.

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    O presente trabalho é responsável por uma pesquisa de mestrado na fase de conclusão sobre a produção de um atlas escolar geográfico municipal aplicado à Educação Básica. O artigo tem como referencial teórico-metodológico os orçamentos da pesquisa-ação, que tem como uma de suas características fundamentais a realização de investigações colaborativas que favoreçam a participação criativa e construtiva dos sujeitos envolvidos.This paper accounts for a master’s research in the conclusion phase about the production of a municipal geographic school atlas applied to Basic Education. The article has as a theoretical-methodological reference the assumptions of action-research, which has as one of its fundamental characteristics the development of collaborative investigations that foster the creative and constructive participation of the subjects involved

    A pesquisa-ação como metodologia na construção do Atlas Escolar Geográfico Municipal de Conceição de Macabu/RJ

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    This paper accounts for a master’s research in the conclusion phase about the production of a municipal geographic school atlas applied to Basic Education. The article has as a theoretical-methodological reference the assumptions of action-research, which has as one of its fundamental characteristics the development of collaborative investigations that foster the creative and constructive participation of the subjects involved.El presente trabajo da cuenta de una investigación de maestría en fase de conclusión sobre la producción de un atlas escolar geográfico municipal aplicado a la Educación Básica. El artículo tiene como referente teórico-metodológico los presupuestos de la investigación-acción, una de cuyas características fundamentales es la realización de investigaciones colaborativas que propician la participación creadora y constructiva de los sujetos involucrados.O presente trabalho é responsável por uma pesquisa de mestrado na fase de conclusão sobre a produção de um atlas escolar geográfico municipal aplicado à Educação Básica. O artigo tem como referencial teórico-metodológico os orçamentos da pesquisa-ação, que tem como uma de suas características fundamentais a realização de investigações colaborativas que favoreçam a participação criativa e construtiva dos sujeitos envolvidos

    MRI investigation of granular interface rheology using a new cylinder shear apparatus

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    The rheology of granular materials near an interface is investigated through proton magnetic resonance imaging. A new cylinder shear apparatus has been inserted in the MRI device, which allows the control of the radial confining pressure exerted by the outer wall on the grains and the measurement of the torque on the inner shearing cylinder. A multi-layer velocimetry sequence has been developed for the simultaneous measurement of velocity profiles in different sample zones, while the measurement of the solid fraction profile is based on static imaging of the sample. This study describes the influence of the roughness of the shearing interface and of the transverse confining walls on the granular interface rheology

    Crescimento e puberdade após tratamento da leucemia linfoblástica aguda

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    Over the last 20 years, after combining treatment of chemotherapy and radiotherapy, there has been an improvement in the survival rate of acute lymphoblastic leukemia patients, with a current cure rate of around 70%. Children with the disease have been enrolled into international treatment protocols designed to improve survival and minimize the serious irreversible late effects. Our oncology unit uses the international protocol: GBTLI LLA-85 and 90, with the drugs methotrexate, cytosine, arabinoside, dexamethasone, and radiotherapy. However, these treatments can cause gonadal damage and growth impairment. PATIENTS AND METHOD: The authors analyzed 20 children off therapy in order to determine the role of the various doses of radiotherapy regarding endocrinological alterations. They were divided into 3 groups according to central nervous system prophylaxis: Group A underwent chemotherapy, group B underwent chemotherapy plus radiotherapy (18 Gy), and group C underwent chemotherapy plus radiotherapy (24 Gy). Serum concentrations of LH, FSH, GH, and testosterone were determined. Imaging studies included bone age, pelvic ultrasound and scrotum, and skull magnetic resonance imaging. RESULTS: Nine of the patients who received radiotherapy had decreased pituitary volume. There was a significant difference in the response to GH and loss of predicted final stature (Bayley-Pinneau) between the 2 irradiated groups and the group that was not irradiated, but there was no difference regarding the radiation doses used (18 or 24 Gy). The final predicted height (Bayley-Pinneau) was significantly less (P = 0.0071) in both groups treated with radiotherapy. Two girls had precocious puberty, and 1 boy with delayed puberty presented calcification of the epididymis. CONCLUSION: Radiotherapy was been responsible for late side effects, especially related to growth and puberty.Nos últimos 20 anos, após o tratamento de pacientes portadores de leucemia linfoblástica aguda, com quimioterapia e radioterapia, houve melhora na taxa de sobrevivência e cura em torno de 70%. Crianças portadoras da doença foram envolvidas em protocolos de tratamento internacionais que visavam melhorar a sobrevida e minimizar os graves e irreversíveis efeitos tardios. A nossa unidade utiliza o protocolo internacional GBTLI LLA-85 e 90, com as drogas metrotexate, citosina, arabinoside, dexametasona e radioterapia .Entretanto, estes tratamentos podem causar insuficiências gonadais e prejuízo no crescimento. PACIENTES E MÉTODO: Os autores analisaram 20 crianças fora de terapia a fim de determinar o papel das várias doses de radioterapia sobre alterações endocrinológicas. Foram divididos em três grupos baseados na profilaxia do sistema nervoso central: o grupo A foi submetido à quimioterapia, o grupo B à quimioterapia mias radioterapia (18Gy) e o grupo C à quimioterapia mais radioterapia (24 Gy). Foram avaliadas as concentrações séricas de LH, FSH, GH e testosterona. Os estudos de imagem incluiram idade óssea, ultrassonografia pélvica, escrotal e ressonância nuclear magnética do crânio. RESULTADOS: Houve diferenças significativas nas respostas do hormônio de crescimento e prejuízo na estatura final (Bayley-Pinneau) entre os dois grupos irradiados e o grupo que não foi irradiado, mas não houve diferenças quando se compararam as doses de radiação utilizadas (18 ou 24 Gy). A previsão da altura final (Bayley-Pinneau) foi menor (p= 0,0071) nos dois grupos tratados com radioterapia. Duas meninas apresentaram puberdade precoce e um menino teve atraso puberal associado a calcificação do epidídimo. CONCLUSÃO: A radioterapia é responsável por efeitos colaterais especialmente quanto ao crescimento e puberdade

    Exploring the measurement of markedness and its relationship with other linguistic variables

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    Antonym pair members can be differentiated by each word's markedness-that distinction attributable to the presence or absence of features at morphological or semantic levels. Morphologically marked words incorporate their unmarked counterpart with additional morphs (e.g., "unlucky" vs. "lucky"); properties used to determine semantically marked words (e.g., "short" vs. "long") are less clearly defined. Despite extensive theoretical scrutiny, the lexical properties of markedness have received scant empirical study. The current paper employs an antonym sequencing approach to measure markedness: establishing markedness probabilities for individual words and evaluating their relationship with other lexical properties (e.g., length, frequency, valence). Regression analyses reveal that markedness probability is, as predicted, related to affixation and also strongly related to valence. Our results support the suggestion that antonym sequence is reflected in discourse, and further analysis demonstrates that markedness probabilities, derived from the antonym sequencing task, reflect the ordering of antonyms within natural language. In line with the Pollyanna Hypothesis, we argue that markedness is closely related to valence; language users demonstrate a tendency to present words evaluated positively ahead of those evaluated negatively if given the choice. Future research should consider the relationship of markedness and valence, and the influence of contextual information in determining which member of an antonym pair is marked or unmarked within discourse

    Search of prostatic tissue in 46,XX congenital adrenal hyperplasia

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    OBJETIVOS: Verificar a ocorrência de tecido prostático em pacientes portadoras da forma clássica de hiperplasia congênita das suprarrenais, com cariótipo 46,XX e analisar a sensibilidade e a especificidade do antígeno prostático específico (PSA) das pacientes com hiperplasia congênita das suprarrenais em relação à detecção de tecido prostático na ressonância magnética (RNM) de região pélvica. MÉTODOS: Foram estudadas 52 crianças e adolescentes, sendo 32 meninas portadoras da forma clássica de hiperplasia congênita das suprarrenais, 10 meninas e 10 meninos sem hiperplasia congênita das suprarrenais. A RNM da região pélvica e a coleta de PSA, diidrotestosterona e testosterona foram realizadas em todos os pacientes. Para analisar a capacidade de discriminação do antígeno prostático-específico, foi utilizada a curva ROC (receiver operating characteristic curve). RESULTADOS: Cinco das 32 pacientes portadoras de hiperplasia congênita das suprarrenais apresentaram tecido prostático na RNM de região pélvica. Para concentração de antígeno prostático-específico de 0,1 ng/mL, obteve-se sensibilidade de 100% e especificidade de 88,9% para a detecção de tecido prostático. CONCLUSÕES: A ocorrência de tecido prostático nas pacientes portadoras de hiperplasia congênita das suprarrenais estudadas foi de 15,6%. O antígeno prostático-específico mostrou ser valioso marcador de tecido prostático nestas pacientes.OBJECTIVES: To describe the presence of prostatic tissue in 46,XX patients with the classical form of congenital adrenal hyperplasia (CAH); to evaluate the sensitivity and specificity of prostatic specific antigen (PSA) measured in congenital adrenal hyperplasia patients with regard to the detection of prostatic tissue in pelvic MRI. METHODS: We studied 52 children and adolescents, 32 with the classical form of congenital adrenal hyperplasia, 10 boys and 10 girls without CAH. Pelvic MRI was performed in all patients to detect prostatic tissue. Prostate specific antigen, testosterone and dihydrotestosterone were measured in all patients. We used Receiver Operating Characteristic Curve for PSA discrimination capacity. RESULTS: Five girls with congenital adrenal hyperplasia showed image of prostatic tissue on pelvic MRI. Prostate specific antigen showed sensitivity and specificity of 100% and 88.9%, respectively, taking 0.1 ng/mL as the cutoff level. CONCLUSIONS: The incidence of prostatic tissue in 46,XX patients with the classical form of congenital adrenal hyperplasia was 15.6%. PSA demonstrated to be a good marker of prostatic tissue in these patients and should be used to screen patients to be submitted to image studies

    Exposure of neonates to Respiratory Syncytial Virus is critical in determining subsequent airway response in adults

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    BACKGROUND: Respiratory syncytial virus (RSV) is the most common cause of acute bronchiolitis in infants and the elderly. Furthermore, epidemiological data suggest that RSV infection during infancy is a potent trigger of subsequent wheeze and asthma development. However, the mechanism by which RSV contributes to asthma is complex and remains largely unknown. A recent study indicates that the age of initial RSV infection is a key factor in determining airway response to RSV rechallenge. We hypothesized that severe RSV infection during neonatal development significantly alters lung structure and the pulmonary immune micro-environment; and thus, neonatal RSV infection is crucial in the development of or predisposition to allergic inflammatory diseases such as asthma. METHODS: To investigate this hypothesis the present study was conducted in a neonatal mouse model of RSV-induced pulmonary inflammation and airway dysfunction. Seven-day-old mice were infected with RSV (2 × 10(5 )TCID(50)/g body weight) and allowed to mature to adulthood. To determine if neonatal RSV infection predisposed adult animals to enhanced pathophysiological responses to allergens, these mice were then sensitized and challenged with ovalbumin. Various endpoints including lung function, histopathology, cytokine production, and cellularity in bronchoalveolar lavage were examined. RESULTS: RSV infection in neonates alone led to inflammatory airway disease characterized by airway hyperreactivity, peribronchial and perivascular inflammation, and subepithelial fibrosis in adults. If early RSV infection was followed by allergen exposure, this pulmonary phenotype was exacerbated. The initial response to neonatal RSV infection resulted in increased TNF-α levels in bronchoalveolar lavage. Interestingly, increased levels of IL-13 and mucus hyperproduction were observed almost three months after the initial infection with RSV. CONCLUSION: Neonatal RSV exposure results in long term pulmonary inflammation and exacerbates allergic airways disease. The early increase in TNF-α in the bronchoalveolar lavage implicates this inflammatory cytokine in orchestrating these events. Finally, the data presented emphasize IL-13 and TNF-α as potential therapeutic targets for treating RSV induced-asthma
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