10 resultados para Radioisotopes in animal culture.
em Brock University, Canada
Resumo:
People with intellectual disability who sexually offend commonly live in community-based settings since the closing of all institutions across the province of Ontario. Nine (n=9) front line staff who provide support to these individuals in three different settings (treatment setting, transitional setting, residential setting) were interviewed. Participants responded to 47 questions to explore how sex offenders with intellectual disability can be supported in the community to prevent re-offenses. Questions encompassed variables that included staff attitudes, various factors impacting support, structural components of the setting, quality of life and the good life, staff training, staff perspectives on treatment, and understanding of risk management. Three overlapping models that have been supported in the literature were used collectively for the basis of this research: The Good Lives Model (Ward & Gannon, 2006; Ward et al., 2007), the quality of life model (Felce & Perry, 1995), and variables associated with risk management. Results of this research showed how this population is being supported in the community with an emphasis on the following elements: positive and objective staff attitude, teamwork, clear rules and protocols, ongoing supervision, consistency, highly trained staff, and environments that promote quality of life. New concepts arose which suggested that all settings display an unequal balance of upholding human rights and managing risks when supporting this high-risk population. This highlights the need for comprehensive assessments in order to match the offender to the proper setting and supports, using an integration of a Risk, Need, Responsivity model and the Good Lives model for offender rehabilitation and to reduce the likelihood of re-offenses.
Resumo:
The article discusses the McDonald's Corporation audit and the ways to improve the handling of livestock on the way to slaughter.
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Interactions between freshwater algae and bacteria were examined in a natural stream habitat and a laboratory model. Field observations provided circumstantial evidence, in statistical correlation for syntrophy between the microbial populations. This relation is probably subject to control by the temperature and pH of the aquatic environment. Several species of a pond community were isolated in axenic culture and tests were performed to determine the nature of mixed species interactions. Isolation procedures and field studies indicated that selected strains of Chlorella and Azotobacter were closely associated in their natural habitat. With the suspected controlling parameters, pH and temperature, held constant, mixed cultures of algae and bacteria were compared to axenic cultures of the same organisms, and a mutual stimulation of growth was observed. A mixed pure culture apparatus was designed in this laboratory to study the algal-bacterial interaction and to test the hypothesis that such an interaction may take place through a diffusable substance or through certain medium-borne conditions, Azotobacter was found to take up a Chlorella-produced exudate, to stimulate protein synthesis, to enhance chlorophyll production and to cause a numerical increase in the interacting Chlorella population. It is not clear whether control is at the environmental, cellular or genetic level in these mixed population interactions. Experimental observations in the model system, taken with field correlations allow one to state that there may be a direct relationship governing the population fluctuations of these two organisms in their natural stream surroundings.
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It has bee1l said that feminism is dead, but in fact feminism is alive in popular cultural fonlls that offer pleasure, style, fUll and advice, as well as political messages that are internalized alld continuously enacted in the lives of North American female youth. This thesis discusses popular feminism with respect to mainstream girls' cultural discourses in music alld magazine reading. Specifically this thesis examines the importance of Madonna, Gwen Stefani, and the Spice Girls, in addition to the numerous girl magazines available on the market today, such as Seventeen and YM. Focusing on the issue of the feminine versus feminist polarity and its importance to girls' culture, this thesis attempts to demonstrate how popular feminism can be used as a mode of empowerment and illustrates the mode of consumption of popular feminist texts that frames female selfimage, attitude, behaviour and speech. Through the employment of popular feminist theories and a discourse alld semiotic analysis of musical lyrics, performance and style, in addition to magazine reading and advertisements, this thesis highlights the use of active media reading and being by girls to gaill an understanding with regards to social positioning and postmodern political identity. More fundamentally, this thesis questions how popular feminism disables, questions and critiques popular ideologies ill a patriarchal society.
Resumo:
In the developing mouse embryo, the diploid trophectoderm is known to undergo a diploid to giant cell transformation. These cells arise by a process of endoreduplication, characterized by replication of the entire genome without subsequent mitosis or cell division, leading to polyploidy and the formation of giant nuclei. Studies of 13.5 day rat trophoblast derived from the parietal yolk sac have indicated a relatively low rate of DNA polymerase a activity, the noinnal eukaryotic replicase, in comparison to that of DNA polymerase g. These results have suggested that endoreduplication in trophoblast giant cells may not employ the normal replicase enzyme, DNA polymerase a. In order to determine whether a 'switch' from DNA polymerase to DNA polymerase is a necessary concomitant of the diploid to giant cell transformation, two distinct populations of trophoblast giant cells, the primary giant cell derived from the mural trophectoderm and the secondary giant cell derived from the polar trophoectoderm were used. These two populations of trophoblast giant cells can be obtained from the tissue outgrowths of 3.5da blastocysts and the extraembryonic ectoderm (EX) and ectoplacental cone (EPC) of 7.5 day embryos respectively. Tissue outgrowths were treated with aphidicolin, a specific reversible inhibitor of eukaryotic DNA polymerase a, on various days after explantation. The effect of aphidicolin treatment was assessed both qualitatively, using autoradiography and quantitatively by scintillation counting and Feulgen staining. 3 DNA synthesis was measured in control and treated cultures after a Hthymidine pulse. Scintillation counts of the embryo proper revealed that DNA synthesis was consistently inhibited by greater than 907. in the presence of aphidicolin. Inhibition of DNA synthesis in the EX and EPC varied between 81-957. and 82-987. respectively, indicating that most DNA synthesis was mediated by DNA polymerase a, but that a small but significant amount of residual synthesis was indicated. A qualitative approach was then applied to determine whether the apparent residual DNA synthesis was restricted to a subpopulation of giant cells or whether all giant cells displayed a low level of DNA synthesis. Autoradiographs of the ICM of blastocysts and the embryo proper of 7.5da embryos, which acted as diploid control population, was completely inhibited regardless of duration in explant culture. In contrast, primary trophoblast giant cells derived from blastocysts and secondary giant cells derived from the EX and EPC were observed to possess some heavily labelled cells after aphidicolin treatment. These results suggest that although DNA polymerase a is the primary replicating enzyme responsible for endoreduplication in mouse trophoblast giant cells, some nonactivity is also observed. A DNA polymerase assay employing tissue lysates of outgrown 7.5da embryo, EX and EPC tissues was used to attempt to confirm the presence of higher nonactivity in tissues possessing trophoblast giant cells. Employing a series of inhibitors of DNA polymerases, it would appear that DNA polymerase a is the major polymerase active in all tissues of the 7.5da mouse embryo. The nature of the putative residual DNA synthetic activity could not be unequivically determined in this study. Therefore, these results suggest that both primary and secondary trophoblast giant cells possess and use DNA polymerase a in endoreduplicative DNA synthesis. It would appear that the high levels of DNA polymerase g activity reported in trophoblast tissue derived from the 13.5 da rat yolk sac was not a general feature of all endoreduplication.
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This thesis explores the comparison utilitarianism and Buddhist ethics as they can be applied to animal research. It begins by examining some of the general discussions surrounding the use of animals in research. The historical views on the moral status of animals, the debate surrounding their use in animals, as well as the current 3R paradigm and its application in Canadian research are explored. The thesis then moves on to expound the moral system of utilitarianism as put forth by Jeremy Bentham and John Stuart Mill, as well as contemporary additions to the system. It also looks at the basics of Buddhist ethics well distinguishing the Mahayana from the Therevada. Three case studies in animal research are used to explore how both systems can be applied to animal research. It then offers a comparison as to how both ethical systems function within the field of animal research and explores the implications in their application on its practice.
Resumo:
This thesis deals with the everyday use of propaganda in Romania, between 1971 and 1989. It explores the way in which the propaganda discourse of the Romanian Communist Party was disseminated through popular culture artifacts targeting children: Pioneers' magazines, textbooks, Almanacs and moralizing stories. These artifacts configured the image of a model child, whose preoccupations complied with the requirements of the Romanian Communist Party and communicated a set of recommended practices, to be followed by Romanian children. At the same time, the thesis incorporates the response of the actual children to these desirable practices, and implicitly, their response to state propaganda.
Resumo:
The developmental remodelling of motivational systems that underlie drug dependence and addiction may account for the greater frequency and severity of drug abuse in adolescence compared to adulthood. Recent advances in animal models have begun to identify the morphological and the molecular factors that are being remodelled, but little is known about the culmination of these factors in altered sensitivity to psycho stimulant drugs, like amphetamine, in adolescence. Amphetamine induces potent locomotor activating effects in rodents through increased dopamine release in the mesocorticolimbic dopamine system, which makes locomotor activity a useful behavioural marker of age differences in amphetamine sensitivity. The aim of the thesis was to investigate the neural basis for age differences in amphetamine sensitivity with a focus on the nucleus accumbens and the medial prefrontal cortex, which initiate and regulate amphetamine-induced locomotor activity, respectively. In study 1, I found pre- and post- pubertal adolescent rats to be less active (i.e., hypoactive) than adults to a first injection of 0.5, but not of 1.5, mg/kg of intraperitonealy (i.p.) administered amphetamine. Although initially hypoactive, only adolescent rats exhibited an increase in activity to a second injection of amphetamine given 24 h later, indicating that adolescents may be more sensitive to the rapid changes in amphetamineinduced plasticity than adults. Given that the locomotor activating effects of amphetamine are initiated in the nucleus accumbens, age differences in response to direct injections of amphetamine into this brain region were investigated in study 2. In contrast to i.p. injections, adolescents were more active than adults when amphetamine was given directly into the nucleus accumbens, indicating that hypo activity may be attributed to the development of regulatory regions outside of the accumbens. The medial prefrontal cortex (mPFC) is a key regulator of the locomotor activating effects of amphetamine that undergoes extensive remodelling in adolescence. In study 3, I found that an i.p. injection of 1.5, and not of 0.5, mg/kg of amphetamine resulted in a high expression of c-fos, a marker of neural activation, in the pre limbic mPFC only in pre-pubertal adolescent rats. This finding suggests that the ability of adolescent rats to overcome hypo activity at the 1.5 mg/kg dose may involve greater activation of the prelimbic mPFC compared to adulthood. In support of this hypothesis, I found that pharmacological inhibition of prelimbic D 1 dopamine receptors disrupted the locomotor activating effects of the 1.5 mg/kg dose of amphetamine to a greater extent in adolescent than in adult rats. In addition, the stimulation of prelimbic D 1 dopamine receptors potentiated locomotor activity at the 0.5 mg/kg dose of amphetamine only in adolescent rats, indicating that the prelimbic D1 dopamine receptors are involved in overcoming locomotor hypoactivity during adolescence. Given my finding that the locomotor activating effects of amphetamine rely on slightly different mechanisms in adolescence than in adulthood, study 4 was designed to determine whether the lasting consequences of drug use would also differ with age. A short period of pre-treatment with 0.5 mg/kg of amphetamine in adolescence, but not in adulthood, resulted in heightened sensitivity to an injection of amphetamine given 30 days after the start of the procedure, when adolescent rats had reached adulthood. The finding of an age-specific increase in amphetamine sensitivity is consistent with evidence for increased risk for addiction when drug use is initiated in adolescence compared to adulthood in people (Merline et aI., 2002), and with the hypothesis that adolescence is a sensitive period of development.
Resumo:
Parent-child sexual health communication can be beneficial. Many factors affect such communication in Chinese immigrant families. This qualitative study explored the influences of acculturation, parenting, and parental participation in the Raising Sexually Healthy Children Program (RSHC) on such communication. With a hermeneutic framework, the purpose was to develop understanding based on the topic, context, and researcher interpretations. Twelve interviews elicited data from six parent-child dyads, three from the RSHC. Analysis involved coding processes; data were compared repeatedly and organized into themes. Perceived personality differences between generations were confounded with cultural communicative differences. Parents used implicitness observed in Chinese culture to establish "open" communication; children expected explicitness observed in Western culture. Post- RSHC, parents perceived themselves as more open to talking about sex; children did not perceive such parental changes. Future research should include joint interviews and longitudinal program evaluation. Future practice should focus on cross-cultural communication and involving children in RSHC.
Resumo:
The purpose of this research project was to explore how women lightweight rowers in Ontario negotiate their gender and body identity. Through a feminist post-structural lens I investigated both ‘acceptable’ and contradictory gender and sport performances that exist in the culture of rowing in order to understand how identity is constructed at the intersection of these discourses. My goal was to learn how human experiences are shaped by discourses of power, and resulting constructions of acceptable gender attributes. Seven university-aged lightweight women’s rowers were interviewed, and the following themes were uncovered: the women are constantly engaging in acts of bodily control; often body image is affected by participation in the sport; there are instances of femininity that exist within the culture of lightweight rowing; inequalities are present within the culture, as are excuse making practices; and the potential for resistance is extremely complicated.