6 resultados para Techniques of Control of Behavior
em Brock University, Canada
Resumo:
The regenerating amphibian limb provides a useful system for studying genes involved in the establishment of positional information. While a number of candidate genes that may playa role in pattern formation have been identified, their function in vivo is unknown in this system. To better ascertain the role of these genes, it would be useful to be able to alter their normal patterns of expression in vivo and to assess the effects of this misexpression on limb pattern. In order to achieve this, a method of introducing a plasmid containing the eDNA of a gene of interest into a newt blastema (a growth zone of mesenchymal progenitor cells) is needed. Unfortunately, most commonly used transfection techniques cannot be used with newt blastema cells. In this study, I have used the techniques of lipofection and direct gene transfer to introduce plasmid DNA containing reporter genes into the cells of a regenerating newt limb. The technique of lipofection was most effective when the blastema cells were transfected in vitro. The optimal ratio for transfection was shown to be 1:3 DNA:Lipofectin (W/w) , and an increase in the amount of DNA present in the mixture (1:3 ratio maintained) resulted in a corresponding increase in gene expression. The technique of direct gene transfer was used to transfect newt blastema cells with and without prior complex formation with Lipofectin. Injection of plasmid DNA alone provided the most 3 promising results. It was possible to introduce plasmid DNA containing the reporter gene ~-galactosidase and achieve significant gene expression in cells associated with the injection site. In the future, it would be interesting to use this technique to inject plasmid DNA containing a gene which may have a role in pattern formation into specific areas of the newt blastema and to analyze the resulting limb pattern that emerges.
Resumo:
Low levels of ionizing radiation induce two translocation responses in soybean: a reduction in photoassimilate export from leaves and a change in the distribution pattern of exported photoassimilate within the plant. In this investigation these responses have been further studied specifically to ascertain the site of radiation damage and to better understand the physiological responses observed. Experimentally the primary data was obtained from studies in which a mature trifoliate leaf of a young soybean plant (Glycine ~ L. cultivar Harosoy '63) is isolated in a closed transparent chamber and allowed to photoassimilate 14C02 for 15 minutes. This is followed by an additional 45 ~_il'1;ute period before the plant is sectl.o ne d an d 14 C-ra dl' oactl.v.l ty d eterml. ne d'l n a 11 parts. Such 14c data provides one with the magnitude and distribution pattern of translocation. Further analyses were conducted to determine the relative levels of the major photosynthetic products using the techniques of paper chromatography and autoradiography. Since differences between control and irradiated P 1 ants were not 0 b serve d l' n t h e par tl't"lo nlng 0 f 14 C between the 80% ethanol-soluble and -insoluble fractions 14 or in the relative amounts of C-products of photosynthesis, the reduction in export in irradiated plants is not likely due to reduced availability of translocatable materials. Data presented in this thesis shows that photoassimilate export was not affected by gamma radiation until a threshold dose between 2.0 and 3.0 krads was reached. It was also observed that radiation-induced damage to the export process was capable of recovery in a period of 1 to 2 hours provided high light intensity was supplied. In contrast, the distribution pattern was shown to be extremely radiosensitive with a low threshold dose between .25 and .49 krads. Although this process was also capable of recovery,lt" occurred much earlier and was followed by a secondary effect which lasted at least for the duration of the experiments. The data presented in this thesis is interpreted to suggest that the sites of radiation action for the two translocation responses are different. In regards to photoassimilate export, the site of action of ionizing radiation is the leaf, quite possibly the process of photophosphorylation which may provide energy directly for phloem loading and for membrane integrity of the phloem tissue* In regards to the pattern of distribution of exported photoassimilate, the site is likely the apical sink, possibly the result of changes of levels of endogenous hormones. By the selection of radiation exposure dose and time post-irradiation, it is possible to affect independently these two processes suggesting that each may be regulated independent of the other and involves a distinct site.
Resumo:
Leisure-based therapy is a potentially effective approach to supporting survivors of trauma in their healing. The purpose ofthis qualitative case study was to describe the recreation therapist's facilitation techniques of Leisure Connections, a unique leisurebased psycho-educational group for survivors of trauma, and explore how the facilitation was experienced by participants. Qualitative case study design, following the methods of Yin (1994) was used. One two week, three session Leisure Connections group was observed. Six participants completed the Group· Therapy Alliance Scale (pinsof & Catherall, 1986) and reflection cards. In-depth, semi-structured interviews were conducted with the recreation therapist and four participants. Six themes emerged describing group leader interventions, recreation therapist's actions, recreation therapist's preparation and reflections, group members' experience of a therapeutic alliance, group cohesion, and prior influences and assumptions. Therapeutic alliance and group cohesion were influenced by the recreation therapist's group leader interventions (drawing out, processing, protecting) and actions. The context of the group within a therapeutic community milieu was an important influence.
Resumo:
This study examined how Outward Bound Western Canada (OBWC) course outcomes are achieved by exploring the relationships among course components, students' characteristics, and course outcomes. OBWC is a wilderness-based adventure education organization that helps students achieve outcomes such as increased self-awareness, self-confidence, motivation, interpersonal skills, concern for others, and concern for the environment. This study explored the ways in which the various components of courses and the characteristics of students contribute to determining the outcomes students experience as a result of their courses. The purpose of the study was to gain a better understanding of how OBWC course outcomes are achieved in order to strengthen adventure education theory, enhance practice at OBWC and other adventure education organizations, and provide a foundation for further research on this topic. As an interpretive case study, this study sought to describe how OBWC course outcomes are achieved and to provide interpretations of the research findings. Data was gathered from OBWC students and instructors using the quantitative and qualitative data collection techniques of questionnaire, interview, and observation. Data collected from 98 participants ensured a considerable breadth to the study, while interviews with a number of participants also enabled the collection of in-depth data. Analysis and triangulation of the data from the various sources allowed discernment of the research findings. A comprehensive and detailed picture of how course outcomes are achieved emerged from the findings. Twenty-nine course components were found to influence course outcomes, including various aspects of course activities, the physical environment, instructors, and the group. The findings indicated that certain course components were most influential in determining increases to students' self-awareness, self-confidence, self-reliance, self-esteem, self-concept, motivation, self-responsibility, interpersonal skills, concern for others, and concern for the environment. A number of course components were found to indirectly contribute to positive course outcomes by helping maximize the effectiveness of other components, by increasing students' motivation while on course, or by facilitating the processing and transference of new information. The findings also suggested that several course components either directly or indirectly affected course outcomes in negative ways. In addition, the gender, age, population, and expectations of students were found to play a role in determining the course outcomes they experienced and in determining which course components caused those outcomes. Interpretation of the findings resulted in the generation of research-based theory. The main theoretical argument derived from the results of the study was that course outcomes are influenced by a combination of course components and characteristics of students. More specifically, the theory generated by the study indicated that five groupings of factors contribute to course outcomes, including course activities, the physical environment, instructors, the group, and students' characteristics. The study was considered in relation to existing adventure education literature and larger theoretical issues. The generated theory and research findings were then used to develop suggestions for improving practice at OBWC and other adventure education organizations, as well as for enhancing future research studies.
Resumo:
Lemna minor is a small aquatic polyploid angiosperm which reproduces apomictically and has a worldwide distribution. This study was vmdertaken to characterize the extent and nature of phenotypic variability. The techniques of starch gel electrophoresis were used in this investigation and. MDH phenotypes of several populations from Ontario, USA and Africa were examined and compared. Heat stability, molecular weight and cell fractionation analyses were also done to identify locus specific MDH bands. The results of the population surveys suggest that there is little genetic variability present both within and between Lemna minor/Lemna turionifera . Evidence of correlation of physiological and seasonal variation patterns was found.
Resumo:
A substantial research literature exists regarding the psychopathy construct in forensic populations, but more recently, the construct has been extended to non-clinical populations. The purpose of the present dissertation was to investigate the content and the correlates of the psychopathy construct, with a particular focus on addressing gaps and controversies in the literature. In Study 1, the role of low anxiety in psychopathy was investigated, as some authors have proposed that low anxiety is integral to the psychopathy construct. Participants (n = 346) responded to two self-report psychopathy scales, the SRP-III and the PPI-R, as well as measures of temperament, personality, and antisociality. Of particular interest was the PPI-R Stress Immunity sub scale, which represents low anxiety content. I t was found that Stress Immunity was not correlated with SRP-III psychopathy, nor did it share common personality or temperament correlates or contribute to the prediction of anti sociality. From Study 1, it was concluded that it was unlikely that low anxiety is a central feature of the psychopathy construct. In Study 2, the relationship between SRP-III psychopathy and Ability Emotional Intelligence (Le., Emotional Intelligence measured as an ability, rather than as a self-report personality trait-like characteristic) was investigated, to determine whether psychopathy is be s t seen as a syndrome characterized by emotional deficits or by the ability to skillfully manipulate and prey upon the others' emotions. A negative correlation between the two constructs was found, suggesting that psychopathy is best characterized by deficits in perceiving, facilitating, managing, and understanding emotions. In Study 3, sex differences in the sexual behavior (i.e., promiscuity, age of first sexual behaviors, extradyadic sexual relations) and appearance-related esteem (i.e., body shame,appearance anxiety, self-esteem) correlates of SRP-III psychopathy were investigated. The sexual behavior correlates of psychopathy were quite similar for men and women, but the esteem correlates were very different, such that high psychopathy in men was related to high esteem, whereas high psychopathy in women was generally related to low esteem. This sex difference was difficult to interpret in that it was not mediated by sexual behavior, suggesting that further exploration of this topic is warranted. Together, these three studies contribute to our understanding of non-clinical psychopathy, indicating that low anxiety is likely not part of the construct, that psychopathy is related to low levels of ability in Emotional Intelligence, and that psychopathy is an important predictor of behavior, ability, and beliefs and feelings about the self