17 resultados para Reared Apart

em Brock University, Canada


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The present study tested the appHcabiUty of Ajzen's (1985) theory of planned behaviour (TPB), an extension of Fishbein and Ajzen's (1975) theory of reasoned action (TRA), for the first time, in the context of abused women's decision to leave their abusive relationships. The TPB, as a means of predicting women's decision to leave their abusive partners' was drawn from Strube's (1988, 1991) proposed decision-making model based on the principle that the decision-making process is a rational, deliberative process, and regardless of outcome, was a result of a logical assessment of the available data. As a means of predicting those behaviours not under volitional control, Ajzen's (1985) TPB incorporated a measure of perceived behavioural control. Data were collected in two phases, ranging from 6 months to 1 year apart. It was hypothesized that, to the extent that an abused woman held positive attitudes, subjective norms conducive to leaving, and perceived control over leaving, she would form an intention to leave and thus, increase the likelihood of actually leaving her partner. Furthermore, it was expected that perceptions of control would predict leaving behaviour over and above attitude and subjective norm. In addition, severity and frequency of abuse were assessed, as were demographic variables. The TPB failed to account significantly for variability in either intentions or leaving behaviour. All of the variance was attributed to those variables associated with the theory of reasoned action, with social influence emerging as the strongest predictor of a woman's intentions. The poor performance of this model is attributed to measurement problems with aspects of attitude and perceived control, as well as a lack of power due to the small sample size. The insufficiency of perceived control to predict behaviour also suggests that, on the surface at least, other factors may be at work in this context. Implications of these results, and recommendations such as, the importance of obtaining representative samples, the inclusion of self-esteem and emotions as predictor variables in this model, a reevaluation of the target behaviovu" as nonvolitional, and longitudinal studies spanning a longer time period for future research within the context of decision-making are discussed.

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Gene therapy is predicated upon efficient gene transfer. While viral vectors are the method of choice for transformation efficiency, the immunogenicity and safety concerns remain problematic. Non-viral vectors, on the other hand, have shown high degrees of safety and are mostly non-immunogenic in nature. However, non-viral vectors usually suffer from low levels oftransformation efficiency and transgene expression. Thus, increasing transformation efficiency ofnon-viral vectors, in particular by calcium phosphate co-precipitation technique, is a way of generating a suitable vector for gene therapy and is the aim of this study. It is a long known fact that different cell lines have different transfection efficiencies regardless oftransfection methodology (Lin et a!., 1994). Using commonly available cell lines Madine-Darby Bovine Kidney (MDBK), HeLa and Human Embryonic Kidney (HEK-293), we have shown a decreasing trend ofDNase activity based on a plasmid digestion assay. From densitometry studies, as much as a 40% reduction in DNase activity was observed when comparing HEK-293 (least active) to MDBK (most active). Using various biochemical assays, it was determined that DNase y, in particular, was expressed more highly in MDBK cells than both HeLa and HEK-293. Upon cloning of the bovine DNase y gene, we utilized the sequence information to construct antisense expressing plasmids via both traditional antisense RNA (pASDGneoM) and siRNA (psiRNA-S4, psiRNA-S11 and psiRNA-S16). For the construction ofpASDGneoM, the 3' end of the DNase y was inserted in opposite orientation under a cytomegalovirus (CMV) promoter such that the expression ofRNA complementary to the DNase 2 ymRNA occurred. For siRNA plasmids, the sequence was screened to yield optimal short sequences for siRNA inhibition. The silencing ofbovine DNase y led to an increase in transfection efficiency based on traditional calcium phosphate co-precipitation technique; stable clones of siRNA-producing MDBK cell lines (psiRNA-S4 Bland psiRNA-S4 B4) both demol).strated 4-fold increases in transfection efficiency. Furthermore, serial transfection of antisense DNase y plasmid pASDGneoM and reporter pCMV-~ showed a maximum of 8-fold increase in transfection efficiency when the two separate transfections were carried out 4 hours apart (i.e. transfection ofpASDGneoM, separated by four hours, then transfection ofpCMV-~). Together, these results demonstrate the involvement ofDNase y in reducing transfection efficiency, at least by traditional calcium phosphate technique.

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Visual stimuli and socialization influence exploratory behaviour in crayfish. The predominant components of spontaneous exploratory behaviour were determined by observing the activity of solitary adult crayfish (Procambarus clarkii) in a glass aquarium containing fresh water and no objects. Five distinct behaviours were observed: rearing up (climbing on the wall), turning around, cornering (facing the comer), backward walking, and crossing (crossing the midline of the aquarium). The frequency of rearing up, cornering and turning around decreased when reflection from the glass wall was blocked with black cardboard, black paint or non-reflective transparent plastic. In a tank containing mirrors on one side and non-reflective plastic on the other, crayfish cornered, reared up, and turned around more in front of the mirrors. Socialization was necessary for crayfish to respond to the reflection. Crayfish that were housed in pairs for two weeks exhibited more rearing up, turning around and cornering in front of the mirrors than in the non-reflective side. Crayfish isolated for two weeks did not show these differences. Socialized crayfish also exhibited more rearing up, turning around and cornering than did isolated crayfish. Thus, crayfish respond to visual stimuli provided by a glass tank, but the responds depends on socialization.

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The freshwater mollusc Lymnaea stagnalis was utilized in this study to further the understanding of how network properties change as a result of associative learning, and to determine whether or not this plasticity is dependent on previous experience during development. The respiratory and neural correlates of operant conditioning were first determined in normally reared Lymnaea. The same procedure was then applied to differentially reared Lymnaea, that is, animals that had never experienced aerial respiration during their development. The aim was to determine whether these animals would demonstrate the same responses to the training paradigm. In normally reared animals, a behavioural reduction in aerial respiration was accompanied by numerous changes within the neural network. Specifically, I provide evidence of changes at the level of the respiratory central pattern generator and the motor output. In the differentially reared animals, there was little behavioural data to suggest learning and memory. There were, however, significant differences in the network parameters, similar to those observed in normally reared animals. This demonstrated an effect of operant conditioning on differentially reared animals. In this thesis, I have identified additional correlates of operant conditioning in normally reared animals and provide evidence of associative learning in differentially reared animals. I conclude plasticity is not dependent on previous experience, but is rather ontogenetically programmed within the neural network.

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Pyruvate dehydrogenase (PDH) is an important regulator of carbohydrate oxidation during exercise and its activity can be down-regulated by an increase in dietary fat. The purpose of this study was to determine the acute metabolic effects of differential dietary fatty acids on the activation of PDH in its active form (PDHa) at rest and at the onset of moderate-intensity exercise. University-aged male subjects (n=7) underwent 2 fat loading trials spaced at least 2 weeks apart. Subjects consumed saturated (SFA) or polyunsaturated (PUFA) fat over the course of 5 hours. Following this, participants cycled at 65% VO2 max for 15 min. Muscle biopsies were taken prior to and following fat loading and at 1 min exercise. Plasma free fatty acids increased from 0.15 ± 0.07 to 0.54 ± 0.19 mM over 5 hours with SFA and from 0.1 1 ± 0.04 to 0.35 ±0.13 mM with PUFA. PDHa activity was unchanged following fat loading, but increased at the onset of exercise in the SFA trial, from 1 .4 ± 0.4 to 2.2 ± 0.4 /xmol/min/kg wet wt. This effect was negated in the PUFA trial (1 .2 ± 0.3 to 1 .3 ± 0.3 pimol/min/kg wet wt.). PDH kinase (PDK) was unchanged in both trials, suggesting that the attenuation of PDHa activity with PUFA was a result of changes in the concentrations of intramitochondrial effectors, more specifically intramitochondrial NADH or Ca^*. Our findings suggest that attenuated PDHa activity participates in the preferential oxidation of PUFA during moderateintensity exercise.

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Although much research has been conducted on blood-meal acquisition in adult female black flies (Diptera: Simuliidae), the same cannot be said for sugarmeals. Both sexes feed on sugar which provides energy for flight and it has been commonly held that nectar is the major carbohydrate source. This thesis addresses the question of whether a non-floral carbohydrate source, specifically homopteran honeydew, is ingested by male and female black flies. Black flies reared in the laboratory have been observed to readily ingest freshly excreted and older (dry) honeydew when presented with honeydew coated tamarack branches. Field work was conducted in Algonquin Park, Ontario in the spring and summer of 1993. Three separate studies were designed to test whether homopteran honeydew is an important carbohydrate source for black flies and whether flies from different habitats utilize different sugar sources. The sugars melezitose and / or stachyose are known to occur in a variety of homopteran honeydews and therefore were used as indicators of honeydew feeding by black flies. In the first study, black flies were collected with insect nets from a stand of Larix larcina heavily infested with honeydew - producing homopterans (Adelges lariciatus). Six black fly species were captured: Simulium venustum, S. rostra tum, S. vittatum, Stegopterna mutata, S. aureum and S. quebecense. Samples of honeydew and individual black flies were tested using thin layer chromatography (T. L. C.) with fructose, glucose, sucrose, turanose, melezitose, raffinose and stachyose as standards. All sugars except turanose and melezitose were found in the adelgid honeydew samples. Since the sugar melezitose was absent from ~ honeydew samples, stachyose was used to indicate that black flies were feeding from this particular honeydew source. Of the 201 black flies tested, 194 contained sugars which occurred in 16 combinations. Stachyose combinations excluding melezitose, present in 45.9 % of flies, were used to indicate that black flies had been feeding on the adelgid honeydew. In the second study, black flies were collected in the morning and evening on 8 collection dates, using a vehicle mounted insect net. The crops and midguts of 10 male and 10 female Simulium venustum were dissected on each sample date. In total the gut contents of 320 individual flies were analysed by T. L. C. The sugars identified from these flies were present in the following proportions: fructose (100.0%), glucose (100.0%), sucrose/turanose (50.4%), melezitose (30.3%), raffinose (18.8%) and stachyose (8.7%). These sugars occurred in fourteen different combinations. It is argued that the presence of melezitose and / or stachyose indicates that black flies had fed on homopteran honeydew. Significantly more female flies (40.0%) than male flies (27.5%) had fed on honeydew. In the third study, adult black flies were sampled by sweep netting vegetation in four habitats in the morning and evening on 8 collection dates. The habitats are as follows: (1) Davies Bog, (2) Abandoned Air Field (dominated by blueberries, Vaccinium spp.), (3) Deciduous Habitat and (4) Coniferous Habitat. Sugars in the crops and midguts of female flies were tested by T. L. C. and, for S. venustum, it was found that significantly fewer flies (18.8%) from the Air Field contained honeydew than from the other three sites (Davies Bog, 34.4%; Deciduous Habitat, 36.2%; Coniferous Habitat, 25.0%). Of the 1287 black flies tested individually by T. L. C. 441 (34.3%) contained melezitose and / or stachyose sugars indicating that this proportion of the population were feeding from Homopteran honeydew. It is therefore clear that floral (nectar) sugars are not the only source of carbohydrates available to black flies.

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Identification of larval simuliids has always been difficult due to the morphological similarity many species bear to one another. For this reason all characters available have been drawn upon to aid in species identification, including head fan ray number. Even in light of an increasing body of anecdotal reports that head fan ray number is not fixed, it has continued to be used to aid species identification. In the current experiment simuliid larvae were reared under controlled laboratory conditions to last instar in one of three feeding regimes. Out of nine trials, the results of six showed a significant inverse relationship between feeding regime and head fan ray number. In addition to the laboratory experiments, larvae were also collected from the field over the course of the spring and summer, 1994. From these samples significant interspecific and intraspecific variations in head fan ray number were found both spatially and temporally within Algonquin Park. From these data it is concluded that head fan ray number for the species analysed is a developmentally plastic character, which varies in response to food availability. Furthermore, given the extreme variations in head fan ray number found in some species, I recommend that head fan ray number not be used as an aid to identification unless it can be shown to be a fixed character for the species in question.

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Rates and products have been determined for the thermal decomposition of bis diphenyl methyl peroxide and diphenyl methyl tert* butyl peroxide at 110@~145@C* The decomposition was uniformly unimolecular with activation energies for the bis diphenyl methyl peroxide in tetrachloroethylene* toluene and nitrobenzene 26,6* 28*3f and 27 Kcals/mole respectively. Diphenyl methyl tert* butyl peroxide showed an activation energy of 38*6 Kcals/mole* About 80-90% of the products in the case of diphenyl methyl peroxide could be explained by the concerted process, this coupled with the negative entropies of activation obtained is a conclusive evidence for the reaction adopting a major concerted path* All the products in the case of diphenyl methyl peroxide could be explained by known reactions of alkoxy radicals* About 80-85% of tert butanol and benzophenone formed suggested far greater cage disproportionation than diffusing apart* Rates of bis triphenyl methyl peroxide have been determined in tetrachloroethylene at 100-120@C* The activation energy was found to be 31 Kcals/mole*

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Pakistan had a plural society per excellence. Its people were divided geographically between two separate regions, spoke different languages, had different cultures and economic structures. Like other plural societies elsewhere, Pakistan also faced the problem of national integration. Cleavages along the lines of traditional attachments are fundamental to any plural society, as they were in Pakistan. But their political manifestation could have been kept within managable limits if the Central Government, overwhelmingly composed of the West Pakistanis, was seriously committed to the task. All that Pakistan needed to maintain her integrated existence was deliberate, calculated and conscious efforts on the part of the Central Government to give the Bengalis, the majority linguistic and geographic group in the country, a partnership in the state of Pakistan, an effective power in the decision-making process of the country, a reasonable share from the economic resources of the country, and to show respect to their hopes and aspirations. In addition, Pakistan needed a national platform to bring her divergent linguistic and geographic groups toge~her for some common, national purpos~s. Political parties were the only institutions which could have served this purpose. Pakistan miserably failed to sustain national political parties and failed to satisfy Bengalis' demands. This failure eventually resulted in the falling apart of the political system of Pakistan in 1971.

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Martin Heidegger's interpretation of the ancients was born out of something like a crisis in the interpretation of the Greeks, which can be characterized as nothing other than the realization of the idea that the Greek philosophers put a serious question mark over existence. This idea, which had its germination in Prussia with Jakob Burckhart and his teacher, but first came to be seriously cultivated in the Philosophy of Friedrich Nietzsche, was the first in depth investigation into whether the Greeks, on the one hand, questioned existence or, on the other hand, put a question mark over existence. To question existence is rather innocuous, since it amounts to little more, in the end, than a child looking up at the stars and asking what it all means. To put a question mark over existence, however, is another business entirely. For the Greeks, as the life work of Martin Heidegger amply demonstrates, the nature of Greek thinking and the objects towards which it is directed follows so absolutely from the tragic view of the human person that, in a certain sense, philosophy is Greek and could only have developed in Greece. Perhaps stating it a little less categorically, philosophy could have developed elsewhere at least to the extent that something like they way the Greeks understood life was at the forefront: presence, in other words. This thesis deals with the problem ofHeidegger's relation to the Greeks, specifically in terms of his understanding of the Greeks and presence. It is the position of this dissertation that the Greek notion of presence is, as Heidegger understands it, the homeliness of the hearth that radiates through all the things that humans concern themselves with. This is thought by Heidegger, as the Greeks did, specifically in contrast with the uncanninesslunhomeliness of the hqrnan apart from his or her concern with things. Therefore, the thesis is an attempt at exposing the relation between presence and the unhomely by situating it withing Greek existence and the meaning of the Greek Philosopher. In order to support this position, the thesis has been divided into five parts. The first two chapters deal with Heidegger's explanation of the relation between Greek notion of physics (Phusis), metaphysics (specifically in relation to an analysis of time and motion in Greek thought), and what Heidegger calls the fundamental attunement of Dasein (boredom). More exactly, it deals with these issues only so far as they allow us to bring out something like the notion of 'presence' in relation to things and homelessness or restlessness in relation to the human being. The rationale for these two chapters in relation to the central problem of the paper is that in Heidegger's elucidation of physics and metaphysics, he conducts his analysis in such a way that he explicitly uncovers that dimension of human existence that he calls the fundamental attunement of Dasein. This fundamental attunement is, in tum, similar to what the Greeks understood as the deinon, the uncanninesslunhomeliness of the human. The third and fourth chapters take as their explicit themes the problem of the Greek understanding of the assertion and the ways in which the person can comport himlherself toward things, two issues which are not separable. The rationale for these two chapters in relation to the central theme of the paper is that Heidegger's analysis of these two areas in Greek thought brings out precisely why the philosopher and the philosophical way of life is the highest mode of existence for the Greeks and how this is thought specifically in tenns of the uncanniness of humans. The final cijapter gives a complete elucidation of presence as the homeliness of the hearth and shows specifically how this is thought of in contradistinction to the uncanny/unhomely for the Greeks. 1I1 This last chapter also explains Martin Heidegger's reaction to the Greek's interpretation of the highest mode of existence, and what he posited as a counter-thought. The essay as a whole is an attempt to fully concertize an important dimension of Heidegger' s understanding of the Greeks, that is, the relation between presence and the deinon or Greek notion ofunhomely, which, to my la)owledge, has not been offered anywhere in commentaries on Heidegger.

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Developing a strong relationship is essential for optimal child development and it is possible for fathers to fully participate in developing this close bond. Men often develop this relationship through interactive play which usually occurs later in their child's development. As a result, fathers often feel dissatisfied with their ability to form a close attachment in the early post-partum period, which in turn may increase their stress level. However, men can be prepared for the transition to fatherhood if they develop the knowledge and skill necessary to create positive relationships with their infants. Infant massage appears to be a viable option for teaching fathers care-giving sensitivity. To build on the notion of teaching fathers attachment system behaviour in early infancy, a quasi-experimental, mixed methods study was employed. Twenty-four infant-father dyads were recruited for the study. The fathers were asked to fill out the Parent Stress Index and a facial cues rating scale at two times, one month apart. The experimental group also participated in an infant massage intervention taught by a Certified Infant Massage Instructor of the International Association of Infant Massage. A repeated measures MANOVA revealed infant massage decreased paternal stress. Qualitatively, the fathers provided rich descriptions of their experience in the baby massage class which provided useful insight into the efficacy of the intervention. Overall, the fathers enjoyed the experience but did not necessarily see the direct benefit of the intervention on their relationship. Recommendations for pre and postnatal education for fathers are made.

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The Dudding group is interested in the application of Density Functional Theory (DFT) in developing asymmetric methodologies, and thus the focus of this dissertation will be on the integration of these approaches. Several interrelated subsets of computer aided design and implementation in catalysis have been addressed during the course of these studies. The first of the aims rested upon the advancement of methodologies for the synthesis of biological active C(1)-chiral 3-methylene-indan-1-ols, which in practice lead to the use of a sequential asymmetric Yamamoto-Sakurai-Hosomi allylation/Mizoroki Heck reaction sequence. An important aspect of this work was the utilization of ortho-substituted arylaldehyde reagents which are known to be a problematic class of substrates for existing asymmetric allylation approaches. The second phase of my research program lead to the further development of asymmetric allylation methods using o-arylaldehyde substrates for synthesis of chiral C(3)-substituted phthalides. Apart from the de novo design of these chemistries in silico, which notably utilized water-tolerant, inexpensive, and relatively environmental benign indium metal, this work represented the first computational study of a stereoselective indium-mediated process. Following from these discoveries was the advent of a related, yet catalytic, Ag(I)-catalyzed approach for preparing C(3)-substituted phthalides that from a practical standpoint was complementary in many ways. Not only did this new methodology build upon my earlier work with the integrated (experimental/computational) use of the Ag(I)-catalyzed asymmetric methods in synthesis, it provided fundamental insight arrived at through DFT calculations, regarding the Yamamoto-Sakurai-Hosomi allylation. The development of ligands for unprecedented asymmetric Lewis base catalysis, especially asymmetric allylations using silver and indium metals, followed as a natural extension from these earlier discoveries. To this end, forthcoming as well was the advancement of a family of disubstituted (N-cyclopropenium guanidine/N-imidazoliumyl substituted cyclopropenylimine) nitrogen adducts that has provided fundamental insight into chemical bonding and offered an unprecedented class of phase transfer catalysts (PTC) having far-reaching potential. Salient features of these disubstituted nitrogen species is unprecedented finding of a cyclopropenium based C-H•••πaryl interaction, as well, the presence of a highly dissociated anion projected them to serve as a catalyst promoting fluorination reactions. Attracted by the timely development of these disubstituted nitrogen adducts my last studies as a PhD scholar has addressed the utility of one of the synthesized disubstituted nitrogen adducts as a valuable catalyst for benzylation of the Schiff base N-diphenyl methylene glycine ethyl ester. Additionally, the catalyst was applied for benzylic fluorination, emerging from this exploration was successful fluorination of benzyl bromide and its derivatives in high yields. A notable feature of this protocol is column-free purification of the product and recovery of the catalyst to use in a further reaction sequence.

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Eleanore Celeste mentions that she may soon receive letters from Arthur since her friend received some after twelve days apart. She mentions some friends and gives updates about them. She is also planning on doing Red Cross work that evening. This letter is labelled number 9.

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Across taxa, the early rearing environment contributes to adult morphological and physiological variation. For example, in birds, environmental temperature plays a key role in shaping bill size and clinal trends across latitudinal/thermal gradients. Such patterns support the role of the bill as a thermal window and in thermal balance. It remains unknown whether bill size and thermal function are reversibly plastic. We raised Japanese quail in warm (308C) or cold (158C) environments and then at a common intermediate temperature. We predicted that birds raised in cold temperatures would develop smaller bills than warm-reared individuals, and that regulation of blood flow to the bill in response to changing temperatures would parallel the bill’s role in thermal balance. Cold-reared birds developed shorter bills, although bill size exhibited ‘catch-up’ growth once adults were placed at a common temperature. Despite having lived in a common thermal environment as adults, individuals that were initially reared in the warmth had higher bill surface temperatures than coldreared individuals, particularly under cold conditions. This suggests that blood vessel density and/or the control over blood flow in the bill retained a memory of early thermal ontogeny. We conclude that post-hatch temperature reversibly affects adult bill morphology but irreversibly influences the thermal physiological role of bills and may play an underappreciated role in avian energetics

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Black and white photograph, 23 ½ cm x 18 cm, of Hamilton Killaly Woodruff. This is a head and shoulders photo in which Mr. Woodruff is wearing a suit jacket and a bow tie. The photographer’s name appears to be Beady. This is enclosed in a folder which has come apart at the folds. The front of the folder is embossed with a W.