1000 resultados para sexual andofmigrate rivers


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BACKGROUND: The widespread occurrence of feminized male fish downstream of some wastewater treatment works has led to substantial interest from ecologists and public health professionals. This concern stems from the view that the effects observed have a parallel in humans, and that both phenomena are caused by exposure to mixtures of contaminants that interfere with reproductive development. The evidence for a "wildlife-human connection" is, however, weak: Testicular dysgenesis syndrome, seen in human males, is most easily reproduced in rodent models by exposure to mixtures of antiandrogenic chemicals. In contrast, the accepted explanation for feminization of wild male fish is that it results mainly from exposure to steroidal estrogens originating primarily from human excretion. OBJECTIVES: We sought to further explore the hypothesis that endocrine disruption in fish is multi-causal, resulting from exposure to mixtures of chemicals with both estrogenic and antiandrogenic properties. METHODS: We used hierarchical generalized linear and generalized additive statistical modeling to explore the associations between modeled concentrations and activities of estrogenic and antiandrogenic chemicals in 30 U.K. rivers and feminized responses seen in wild fish living in these rivers. RESULTS: In addition to the estrogenic substances, antiandrogenic activity was prevalent in almost all treated sewage effluents tested. Further, the results of the modeling demonstrated that feminizing effects in wild fish could be best modeled as a function of their predicted exposure to both anti-androgens and estrogens or to antiandrogens alone. CONCLUSION: The results provide a strong argument for a multicausal etiology of widespread feminization of wild fish in U.K. rivers involving contributions from both steroidal estrogens and xeno-estrogens and from other (as yet unknown) contaminants with antiandrogenic properties. These results may add farther credence to the hypothesis that endocrine-disrupting effects seen in wild fish and in humans are caused by similar combinations of endocrine-disrupting chemical cocktails.

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This brief paper discusses the assumption that watercourses might be harbouring a chemical(s) affecting the sexual development in fish. Male fish was found with the oestrogen-dependent blood protein, vitellogenin, usually found only in maturing females. The author examines a number of man-made chemicals present in the environment have been found to be oestrogenic. The paper concludes that rivers contain environmental oestrogens that are capable of causing disruptions in the sexual development of fish. Whether or not these environmental oestrogens are causing a widespread disruption in reproduction in wild fish, however, has yet to be determined.

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We measured canine teeth from 28 woolly spider monkeys (Brachyteles arachnoides) to assess sexual dimorphism and population differences. The specimens are from the Brazilian states of Bahia, Minas Gerais, Espírito Santo, Rio de Janeiro, and São Paulo. We found strong sexual dimorphism in canine length for individuals belonging to populations south of 22°00′ latitude but no sexual dimorphism in canine length from individuals of populations north of 21°00′ latitude. Canine length did not vary among females of northern and southern populations. However, southern males had significantly longer canines than northern males. This geographical difference in canine morphology, together with the presence or absence of thumbs and published accounts of differences in genetics and social structure between northern and southern populations, suggests that Brachyteles arachnoides may be composed of at least two subspecies, which appear to be separated by the rivers Grande and Paraiba do Sul and the Serra da Mantiqueira. © 1993 Plenum Publishing Corporation.

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Este estudo teve como contexto uma escola ribeirinha no município de Breves, situado na Ilha do Marajó, no Estado do Pará. Objetivo mestre: Analisar as representações sociais de jovens-alunos do ensino fundamental da Escola Municipal de Ensino Fundamental São Francisco, da Comunidade São Francisco, no município de Breves sobre exploração sexual nas balsas do Marajó e as implicações nas suas vidas escolares. Objetivos condutores: Identificar o perfil dos alunos-jovens; Verificar as imagens e os significados destes alunos-jovens sobre a exploração sexual juvenil; Destacar as objetivações e as ancoragens como elementos que compõem as Representações Sociais de alunos-jovens e alunas-jovens sobre a exploração sexual juvenil; Relacionar as Representações Sociais de alunos e alunas jovens sobre a exploração sexual juvenil nas balsas do Marajó e as implicações nas suas vidas escolares. Participaram deste estudo 16 jovens, na faixa etária entre 14 e 20 anos, matriculados entre a 4ª e 6ª série do ensino fundamental. Tratou-se de uma pesquisa qualitativa-descritiva. O referencial teórico foi a Teoria das Representações Sociais – TRS, com base em Moscovici (2010) e Nascimento (2002). A análise de dados se deu a partir dos referenciais metodológicos de Franco (2008) e Nascimento e Moraes (2010); As Representações Sociais dos jovens-alunos sobre a exploração sexual juvenil nas balsas do Marajó constituíram-se no Rio de possibilidades, cuja imagem se apresenta pelo encantamento, e Rio que traga, imagem representada pelo desencantamento. Além destas RS, destacaram-se significações cuja imagem foi o sentimento de culpa, que se destaca como significado de ser julgado pela comunidade, ter a atribuição de balseira, medo de sofrer ameaças e pelo sentimento de ausência do poder público. A partir destas significações, ressaltamos enquanto ponto de ancoragem o silêncio. Este sentimento que não se pode ouvir brada de sentidos, ora pelo medo de sofrer alguma espécie de julgamento social ora pelo sentimento de esvaziamento que esta condição da exploração sexual se materializa em suas vivências. As implicações escolares constituídas a partir das Representações Sociais de jovens-alunos sobre a exploração sexual juvenil foram: fragilização na formação escolar e no processo psicossocial de desenvolvimento juvenil; falta de aprendizagem; desatenção nos conteúdos e atividades escolares; desinteresse pela escolarização (Abandono escolar e Repetência escolar). Estes elementos e as análises teóricas articuladas a partir dessas Representações Sociais nos apontam como conclusão que a exploração sexual nos rios e furos da paisagem amazônica ainda é pouco visível, uma vez que as ações do poder público ainda não dão o lugar para este fenômeno no sentido de seu combate e enfrentamento. Entendemos, portanto, que deve haver uma ação educativa que possibilite o enfrentamento da exploração sexual juvenil.

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The specific mechanisms by which selective pressures affect individuals are often difficult to resolve. In tephritid fruit flies, males respond strongly and positively to certain plant derived chemicals. Sexual selection by female choice has been hypothesized as the mechanism driving this behaviour in certain species, as females preferentially mate with males that have fed on these chemicals. This hypothesis is, to date, based on studies of only very few species and its generality is largely untested. We tested the hypothesis on different spatial scales (small cage and seminatural field-cage) using the monophagous fruit fly, Bactrocera cacuminata. This species is known to respond to methyl eugenol (ME), a chemical found in many plant species and one upon which previous studies have focused. Contrary to expectation, no obvious female choice was apparent in selecting ME-fed males over unfed males as measured by the number of matings achieved over time, copulation duration, or time of copulation initiation. However, the number of matings achieved by ME-fed males was significantly greater than unfed males 16 and 32 days after exposure to ME in small cages (but not in a field-cage). This delayed advantage suggests that ME may not influence the pheromone system of B. cacuminata but may have other consequences, acting on some other fitness consequence (e.g., enhancement of physiology or survival) of male exposure to these chemicals. We discuss the ecological and evolutionary implications of our findings to explore alternate hypotheses to explain the patterns of response of dacine fruit flies to specific plant-derived chemicals.

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Objective: There is a paucity of information regarding cases of multi-victim sexual assault of children. The reported incidence suggests that these cases are rare. The aim of this paper is to provide practitioners with information about effective intervention strategies arising out of the direct experience of managing a case of multi-victim sexual assault in an Australian rural community. --------- Method: A descriptive, case-report methodology summarizing the investigation and intervention in a case of multi-victim sexual assault is reported. A community based intervention arising out of the disclosures of 21 male children is described. The intervention occurred at an individual, group, and community level using a coordinated multi-disciplinary team and natural helping networks. ---------- Results: The coordination of police and welfare services increased the communication flow to victims, their families, and the community. The case also demonstrated the utility in regularly briefing political and bureaucratic authorities as well as local officials about emergent issues. Coordinating political and bureaucratic responses was essential in obtaining ongoing support and sufficient researching to enable the effective delivery of services. ---------- Conclusions: Interventions were focused at an individual, group, and community level using a coordinated multi-disciplinary team and natural helping networks. This provided a choice of services which were sensitive to the case setting. Recommendations are offered for practitioners who are confronted with similar events. While this paper describes an approach for intervening in a case of multi-victim sexual assault, further empirical research is needed to enable service deliverers to efficaciously target interventions which offer choice to victims and their families.

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Sexual harassment can be conceptualised as an interaction between harassers and targets. Utilising 23 detailed legal transcripts, this study explored evidence of a range of perpetrator tactics and target counter-tactics. These tactics can be readily fitted into the backfire framework, which proposes that powerful perpetrators of perceived unjust acts are likely to cover up the actions, devalue the target, reinterpret the events, use official channels to give an appearance of justice, and intimidate or bribe people involved. Targets can respond using counter-tactics of exposure, validation, reframing, mobilisation of support, and resistance. The findings have implications for raising awareness of harassing tactics and recommendations for effective informal responses in organisations.

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The paper uses qualitative textual analysis to compare journalistic and academic accounts of child sexual abuse. There are seven main differences. Academic accounts suggest higher levels of neglect, emotional abuse, and physical abuse than sexual abuse in Australia, by contrast, journalistic accounts highlight sexual abuse. Academic accounts suggest that child sexual abuse in Australia is decreasing; journalistic accounts suggest that it is increasing. Academic accounts suggest that the majority of cases of child sexual abuse are perpetrated by family members; journalistic accounts focus on abuse by institutional figures (teachers, priests) or by strangers. Academic accounts have shown that innocent sexual play is a normal part of childhood development; journalistic accounts suggest that any sexual play is either a sign of abuse, or in itself constitutes sexual abuse. Academic accounts suggest that one of the best ways to prevent sexual abuse is for children to receive sex education; journalistic accounts suggest that children finding out about sex leads to sexual abuse. Academic accounts can gather data from the victims; journalistic accounts are excluded from doing so. Academic researchers talk to abusers in order to understand how child sexual abuse can be prevented; journalistic accounts exclude the voices of child sexual abusers.

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Over 3000 cases of child sexual abuse are identified every year in Australia, but the real incidence is higher still. As a strategy to identify child sexual abuse, Australian States and Territories have enacted legislation requiring members of selected professions, including teachers, to report suspected cases. In addition, policy-based reporting obligations have been developed by professions, including the teaching profession. These legislative and industry-based developments have occurred in a context of growing awareness of the incidence and consequences of child sexual abuse. Teachers have frequent contact and close relationships with children, and possess expertise in monitoring changes in children’s behaviour. Accordingly, teachers are seen as being well-placed to detect and report suspected child sexual abuse. To date, however, there has been little empirical research into the operation of these reporting duties. The extent of teachers’ awareness of their duties to report child sexual abuse is unknown. Further, there is little evidence about teachers’ past reporting practice. Teachers’ duties to report sexual abuse, especially those in legislation, differ between States, and it is not known whether or how these differences affect reporting practice. This article presents results from the first large-scale Australian survey of teachers in three States with different reporting laws: New South Wales, Queensland, and Western Australia. The results indicate levels of teacher knowledge of reporting duties, reveal evidence about past reporting practice, and provide insights into anticipated future reporting practice and legal compliance. The findings have implications for reform of legislation and policy, training of teachers about the reporting of child sexual abuse, and enhancement of child protection.