Insulin signalling is an essential process in humans by which the level of plasma glucose is maintained within the physiologically healthy range. Insulin activates the phosphoinositide 3 kinase (PI3K) signalling pathway that generates the phospholipid messenger PtdIns(3,4,5)P3, which in turn enhances the activity of two important proteins, AKT and Rac1. This then leads to increase the presence of the glucose transporter 4 (GLUT4) at the plasma membrane that enhances the intake of glucose, particularly in skeletal muscle cells and adipocytes. Insulin signalling also triggers interconversion of several other phosphoinositides (PIs) which play pivotal roles in different steps of glucose regulation. PtdIns5P is an important PI that is robustly increased after insulin treatment in the skeletal muscle cell line, L6 myotubes. Many of PtdIns5P`s functions are not fully understood. To gain more knowledge of the role of PtdIns5P in insulin signalling in muscle cells, the PtdIns5P kinase phosphatidylinositol-5-phosphate 4-kinase a (PIP4K2a) was over-expressed in L6 myotubes as a way of removing PtdIns5P, and the consequences in insulin signalling were studied. Although PtdIns5P is converted by PIP4K2a to PtdIns(4,5)P2 which is a precursor of the potent PI PtdIns(3,4,5)P3, previous studies revealed that the increase in PtdIns(3,4,5)P3 induced by insulin in control cells is diminished in cells overexpressing PIP4K2a, for unknown reasons. Additionally, although the phosphorylation of the serine/threonine protein kinase AKT was not affected in these L6 cells, glucose uptake was attenuated. The current study investigates the possible causes of attenuating glucose uptake in PIP4K overexpressing myotubes by examining the small GTPase Rac1 which plays an important role in the cytoskeleton re-arrangement that is necessary for GLUT4 translocation. Furthermore, the possible roles of PI phosphatases that may cause the disturbance on the levels of PIs in response to insulin were evaluated. Additionally, the potential role of PtdIns5P in Rac1 activation in L6 myotubes was further investigated by delivering synthetic PtdIns5P using a carrier-based delivery approach. The results showed that the attenuation of glucose uptake documented in previous studies occurred as a result of a defect in the process of translocating GLUT4 from intracellular storage to the plasma membrane. Rac1 activity was significantly reduced in cells expressing PIP4K2a. Quantifying the level of PIs suggested that PIP4K2a expression increases the removal of PtdIns(3,4,5)P3 by the PI 5-phosphatase, SKIP. Silencing the expression of SKIP by siRNA restored the level of PtdIns(3,4,5)P3 but Rac1 activity and the attenuation GLUT4 translocation were not rescued possibly as a result of removing PtdIns5P by PIP4K2a. On the other hand, exogenous delivery of PtdIns5P in L6 myotubes activates both Rac1 and GLUT4 translocation in the absence of insulin. However, activating GLUT4 translocation by the exogenous PtdIns5P requires PI3K activity since redistribution of GLUT4 to the plasma membrane is inhibited by the PI3K inhibitor, wortmannin. Removing PtdIns5P reduces Rac1 activity and stimulates SKIP that inhibits PtdIns(3,4,5)P3 increase which attenuates GLUT4 translocation and hence glucose uptake. These results emphasise the critical role played by PtdIns5P which seems to serve as a regulator of insulin signalling, both directly and/or by regulating other enzymes involved in the metabolism of PIs.

This thesis focuses on the logical design of binary adders. It covers topics extending from cardinal numbers to carry skip optimization. The conventional adder designs are described in detail, including: carry completion, ripple carry, carry select, carry skip, conditional sum, and carry lookahead. We show that the method of parallel prefix analysis can be used to unify the conventional adder designs under one parameterized model. The parallel prefix model also produces other useful configurations, and can be used with carry operator variations that are associative. Parallel prefix adder parameters include group sizes, tree shape, and device sizes. We also introduce a general algorithm for group size optimization. Code for this algorithm is available on the World Wide Web. Finally, the thesis shows the derivation for some carry operator variations including those originally given by Majerski and Ling. / text

The parental stock of meat type chickens (broiler breeders) are commonly feed restricted to decrease their rapid growth and the issues associated with it. Among these birds, chronic hunger and stress are the most prominent welfare concerns and mass heterogeneity within flocks a major management challenge. The present study compared small and large broiler breeders of the same age within a flock, with the hypothesis that small birds would show signs of poorer welfare indicated by higher corticosterone concentration and heterophil/lymphocyte ratio as a consequence of higher experienced feed restriction due to competition. It also aimed to characterize morphometric differences between small and large birds within flocks as well as between birds on different feeding regimens; skip-a-day vs. every-day-fed. Heterophil/lymphocyte ratio at 4 weeks was significantly higher in large birds compared to small birds, but corticosterone concentration did not differ. Relative mass of the upper gastrointestinal tract, pancreas and liver of small birds at 4 weeks of age were significantly larger, while relative muscle and gizzard fat mass were significantly lower compared to large birds. 12 weeks old skip-a-day fed birds largely followed the pattern of 4 weeks old small birds. In the present study, no clear signs of poorer welfare in small broiler breeders could be seen and the morphometric differences might suggest different ways to cope with feed competition. A larger gastrointestinal tract might indicate long-term investments and maybe that smaller broiler breeders, and skip-a-day fed birds, are better habituated to feed restriction.

Bedload transport studies are essential in the understanding of river forms, functions and processes. These studies have been done using various methods over the past century. In recent years Radio Frequency Identification Technology (RFID) has become popular with researchers to track bedload particles. However, no standard operating procedures are used in the implementation of this technology. Methods used for tagging, seeding and tracking RFID tracers (RFID transponders inserted into a bedload particle) can introduce variability in their detection. In this study, RFID tracers were used to study four sites in Laurel Creek in Waterloo, Ontario. Two hundred RFID tracers were seeded in each of the four sites. Following three major storm events, the tracers were tracked with an antenna and their locations surveyed. The tracers were able to be detected to a precision of 1 m as a transponder used can be detected at a maximum of this distance. Practical tracking in the field highlighted the need for the understanding of how precisely the tag location can be identified. Laboratory experiments were designed and carried out to determine the effects of factors (tracer orientation, antenna orientation, tracer size, clustering of multiple tracers, burial depth, saturation and submergence of the soil matrix) that possibly confounded detection. Of these factors, tracer orientation, clustering and burial depths were determined to be the ones that affected detection distances the most. A transponder in a vertical orientation was found to have as much as 40% larger range of detection than a transponder in a horizontal orientation (i.e., they could be detected from further away). Additionally, “skip zones” were identified during laboratory and field experiments. These are zones of gaps in the electromagnetic field of the transponder that occur directly over the transponder. These zones were experimentally determined to extend to approximately 10 cm on each side of the transponder. Therefore, by identifying the skip zones, the tracers can be located to a precision of 10 cm; this is an order of magnitude smaller than the published detection limit of the transponder. The precision of detection can also be improved by the reduction of the effects of confounding factors. However, the improvement in the precision of detection is a tradeoff with the ease of detection. A tagging, seeding and tracking protocol is recommended to counter the effects of confounding factors.

É relatado que em um alto percentual de granjas comerciais há uma queda de produtividade no segundo parto com relação ao primeiro, conhecida como a síndrome do segundo parto. Com o objetivo de analisar alternativas para aumentar o desempenho reprodutivo de secundíparas, um total de 663 primíparas foram desmamadas em média com três semanas de lactação e divididas em três tratamentos: T1, primíparas cobertas no primeiro estro após o desmame; T2, primíparas cobertas no segundo estro após o desmame; e T3, primíparas submetidas à hormonioterapia com altrenogest por cinco dias após o desmame e cobertas no primeiro estro após a retirada do produto. As fêmeas foram alocadas nos tratamentos conforme linhagem genética, leitões nascidos totais, leitões desmamados, escore corporal visual e duração da lactação anterior. Primíparas do T1 e T3 perderam peso no intervalo desmame e cobertura (4,5 e 2,0%, respectivamente), havendo ganho de peso nas primíparas do T2 (1,3%), sendo as perdas de peso diferentes entre os tratamentos (P<0,05). As primíparas do T1 e T2 apresentaram maior porcentagem de fêmeas em estro até 10 dias após o desmame ou retirada do altrenogest (94,1 e 95,0%, respectivamente) do que o T3 (86,4%, P<0,05). O intervalo desmame-estro foi semelhante entre T1 e T2, sendo maior que o intervalo retirada do altrenogest-estro do T3 (P<0,05). A taxa de parto e a taxa de parto ajustada foram mais altas (P<0,05) no T2 (94,3 e 95,7%) seguida pelo T1 (87,0 e 88,0%) e T3 (69,1 e 69,1%). O número de leitões nascidos totais e vivos foram maiores (P<0,05) no T2 (13,5 ± 0,2 e 12,7 ± 0,2), seguido pelo T1 (11,0 ± 0,2 e 10,4 ± 0,2) e T3 (9,8 ± 0,3 e 9,3 ± 0,3). Houve recuperação corporal e bons resultados reprodutivos das fêmeas cobertas no segundo estro quando fornecida uma quantidade de ração padronizada no IDCOB (4.0 kg/dia), além de ser uma técnica viável na prática, como evidenciado pelo alto percentual de fêmeas retornando à ciclicidade. Parece que para que haja um bom desempenho em primíparas tratadas com altrenogest é necessário um tratamento mais prolongado (12 a 18 dias). A perda de peso devido ao catabolismo lactacional persiste após o desmame como demonstrado pela perda de peso do grupo controle e do tratado com altrenogest no período entre o desmame e a cobertura. / In a high percentage of commercial farms, it is reported that productivity decreases during the second farrowing compared to the first, known as the second litter syndrome. In order to compare commonly used management in farms (breeding at the first estrus post-weaning) with breeding at the second estrus (“skip a heat”) or after the utilization of a progestagen analogue (altrenogest) post-weaning, a total of 663 primiparous were weaned on average at three weeks of lactation and divided into three treatments: T1, breeding at the first estrus post-weaning; T2, breeding at the second estrus post-weaning; and T3, primiparous treated with altrenogest five days after weaning and breeding at the first estrus after altrenogest withdrawal. Sows were allocated according to the genetic line, total born, weaned piglets, visual body condition score and previous lactation length. The percentage of weight loss between weaning and insemination was different among treatment groups (P<0.05), considering that T1 and T3 primiparous lost weight. T1 and T2 had greater percentage of females showing estrus within 10 days after weaning/altrenogest withdrawal (94.1 and 95.0% respectively) than T3 (86.4%, P<0.05). The altrenogest withdrawal to insemination interval was smaller than T1 and T2 weaning to estrus interval (P<0.05). Farrowing rate and adjusted farrowing rate were higher (P<0,05) in T2 (94,3 and 95,7%) followed by T1 (87,0 and 88,0%) and T3 (69,1 and 69,1%). The number of total piglets born and alive were higher in T2 (13,5 ± 0,2 and 12,7 ± 0,2), followed by T1 (11,0 ± 0,2 and 10,4 ± 0,2) and T3 (9,8 ± 0.3 and 9,3 ± 0,3). There were body recovery and better reproductive performance in females breed at second estrus, besides being a viable technique in practice, as evidenced by high percentage of females showing second estrus. It appears that for a better performance in primiparous treated with altrenogest is necessary longer (12 to 18 days) period of treatment than five days. The weight loss due lactational catabolism persists after weaning as demonstrated by control and altrenogest treated group weight loss between weaning and insemination.

É relatado que em um alto percentual de granjas comerciais há uma queda de produtividade no segundo parto com relação ao primeiro, conhecida como a síndrome do segundo parto. Com o objetivo de analisar alternativas para aumentar o desempenho reprodutivo de secundíparas, um total de 663 primíparas foram desmamadas em média com três semanas de lactação e divididas em três tratamentos: T1, primíparas cobertas no primeiro estro após o desmame; T2, primíparas cobertas no segundo estro após o desmame; e T3, primíparas submetidas à hormonioterapia com altrenogest por cinco dias após o desmame e cobertas no primeiro estro após a retirada do produto. As fêmeas foram alocadas nos tratamentos conforme linhagem genética, leitões nascidos totais, leitões desmamados, escore corporal visual e duração da lactação anterior. Primíparas do T1 e T3 perderam peso no intervalo desmame e cobertura (4,5 e 2,0%, respectivamente), havendo ganho de peso nas primíparas do T2 (1,3%), sendo as perdas de peso diferentes entre os tratamentos (P<0,05). As primíparas do T1 e T2 apresentaram maior porcentagem de fêmeas em estro até 10 dias após o desmame ou retirada do altrenogest (94,1 e 95,0%, respectivamente) do que o T3 (86,4%, P<0,05). O intervalo desmame-estro foi semelhante entre T1 e T2, sendo maior que o intervalo retirada do altrenogest-estro do T3 (P<0,05). A taxa de parto e a taxa de parto ajustada foram mais altas (P<0,05) no T2 (94,3 e 95,7%) seguida pelo T1 (87,0 e 88,0%) e T3 (69,1 e 69,1%). O número de leitões nascidos totais e vivos foram maiores (P<0,05) no T2 (13,5 ± 0,2 e 12,7 ± 0,2), seguido pelo T1 (11,0 ± 0,2 e 10,4 ± 0,2) e T3 (9,8 ± 0,3 e 9,3 ± 0,3). Houve recuperação corporal e bons resultados reprodutivos das fêmeas cobertas no segundo estro quando fornecida uma quantidade de ração padronizada no IDCOB (4.0 kg/dia), além de ser uma técnica viável na prática, como evidenciado pelo alto percentual de fêmeas retornando à ciclicidade. Parece que para que haja um bom desempenho em primíparas tratadas com altrenogest é necessário um tratamento mais prolongado (12 a 18 dias). A perda de peso devido ao catabolismo lactacional persiste após o desmame como demonstrado pela perda de peso do grupo controle e do tratado com altrenogest no período entre o desmame e a cobertura. / In a high percentage of commercial farms, it is reported that productivity decreases during the second farrowing compared to the first, known as the second litter syndrome. In order to compare commonly used management in farms (breeding at the first estrus post-weaning) with breeding at the second estrus (“skip a heat”) or after the utilization of a progestagen analogue (altrenogest) post-weaning, a total of 663 primiparous were weaned on average at three weeks of lactation and divided into three treatments: T1, breeding at the first estrus post-weaning; T2, breeding at the second estrus post-weaning; and T3, primiparous treated with altrenogest five days after weaning and breeding at the first estrus after altrenogest withdrawal. Sows were allocated according to the genetic line, total born, weaned piglets, visual body condition score and previous lactation length. The percentage of weight loss between weaning and insemination was different among treatment groups (P<0.05), considering that T1 and T3 primiparous lost weight. T1 and T2 had greater percentage of females showing estrus within 10 days after weaning/altrenogest withdrawal (94.1 and 95.0% respectively) than T3 (86.4%, P<0.05). The altrenogest withdrawal to insemination interval was smaller than T1 and T2 weaning to estrus interval (P<0.05). Farrowing rate and adjusted farrowing rate were higher (P<0,05) in T2 (94,3 and 95,7%) followed by T1 (87,0 and 88,0%) and T3 (69,1 and 69,1%). The number of total piglets born and alive were higher in T2 (13,5 ± 0,2 and 12,7 ± 0,2), followed by T1 (11,0 ± 0,2 and 10,4 ± 0,2) and T3 (9,8 ± 0.3 and 9,3 ± 0,3). There were body recovery and better reproductive performance in females breed at second estrus, besides being a viable technique in practice, as evidenced by high percentage of females showing second estrus. It appears that for a better performance in primiparous treated with altrenogest is necessary longer (12 to 18 days) period of treatment than five days. The weight loss due lactational catabolism persists after weaning as demonstrated by control and altrenogest treated group weight loss between weaning and insemination.

SKIP and BIR/Survivin are evolutionarily conserved proteins. SKIP is a known transcription and splicing cofactor while BIR-1/Survivin regulates cell division, gene expression and development. Loss of function of C. elegans SKIP (SKP-1) and BIR-1 induces overlapping developmental phenotypes. In order to uncover the possible interactions of SKP-1 and BIR-1 on the protein level, we screened the complete C. elegans mRNA library using the yeast two-hybrid system. These experiments identified partially overlapping categories of proteins as SKP-1 and BIR-1 interactors. The interacting proteins included ribosomal proteins, transcription factors, translation factors and cytoskeletal and motor proteins suggesting involvement of the two studied proteins in multiple protein complexes. To visualize the effect of BIR-1 on the proteome of C. elegans we induced a short time pulse BIR-1 overexpression in synchronized L1 larvae. This led to a dramatic alteration of the whole proteome pattern indicating that BIR-1 alone has the capacity to alter the chromatographic profile of many target proteins including proteins found to be interactors in yeast two hybrid screens. The results were validated for ribosomal proteins RPS-3, RPL-5, non-muscle myosin and TAC-1, a transcription cofactor and a centrosome associated...

É relatado que em um alto percentual de granjas comerciais há uma queda de produtividade no segundo parto com relação ao primeiro, conhecida como a síndrome do segundo parto. Com o objetivo de analisar alternativas para aumentar o desempenho reprodutivo de secundíparas, um total de 663 primíparas foram desmamadas em média com três semanas de lactação e divididas em três tratamentos: T1, primíparas cobertas no primeiro estro após o desmame; T2, primíparas cobertas no segundo estro após o desmame; e T3, primíparas submetidas à hormonioterapia com altrenogest por cinco dias após o desmame e cobertas no primeiro estro após a retirada do produto. As fêmeas foram alocadas nos tratamentos conforme linhagem genética, leitões nascidos totais, leitões desmamados, escore corporal visual e duração da lactação anterior. Primíparas do T1 e T3 perderam peso no intervalo desmame e cobertura (4,5 e 2,0%, respectivamente), havendo ganho de peso nas primíparas do T2 (1,3%), sendo as perdas de peso diferentes entre os tratamentos (P<0,05). As primíparas do T1 e T2 apresentaram maior porcentagem de fêmeas em estro até 10 dias após o desmame ou retirada do altrenogest (94,1 e 95,0%, respectivamente) do que o T3 (86,4%, P<0,05). O intervalo desmame-estro foi semelhante entre T1 e T2, sendo maior que o intervalo retirada do altrenogest-estro do T3 (P<0,05). A taxa de parto e a taxa de parto ajustada foram mais altas (P<0,05) no T2 (94,3 e 95,7%) seguida pelo T1 (87,0 e 88,0%) e T3 (69,1 e 69,1%). O número de leitões nascidos totais e vivos foram maiores (P<0,05) no T2 (13,5 ± 0,2 e 12,7 ± 0,2), seguido pelo T1 (11,0 ± 0,2 e 10,4 ± 0,2) e T3 (9,8 ± 0,3 e 9,3 ± 0,3). Houve recuperação corporal e bons resultados reprodutivos das fêmeas cobertas no segundo estro quando fornecida uma quantidade de ração padronizada no IDCOB (4.0 kg/dia), além de ser uma técnica viável na prática, como evidenciado pelo alto percentual de fêmeas retornando à ciclicidade. Parece que para que haja um bom desempenho em primíparas tratadas com altrenogest é necessário um tratamento mais prolongado (12 a 18 dias). A perda de peso devido ao catabolismo lactacional persiste após o desmame como demonstrado pela perda de peso do grupo controle e do tratado com altrenogest no período entre o desmame e a cobertura. / In a high percentage of commercial farms, it is reported that productivity decreases during the second farrowing compared to the first, known as the second litter syndrome. In order to compare commonly used management in farms (breeding at the first estrus post-weaning) with breeding at the second estrus (“skip a heat”) or after the utilization of a progestagen analogue (altrenogest) post-weaning, a total of 663 primiparous were weaned on average at three weeks of lactation and divided into three treatments: T1, breeding at the first estrus post-weaning; T2, breeding at the second estrus post-weaning; and T3, primiparous treated with altrenogest five days after weaning and breeding at the first estrus after altrenogest withdrawal. Sows were allocated according to the genetic line, total born, weaned piglets, visual body condition score and previous lactation length. The percentage of weight loss between weaning and insemination was different among treatment groups (P<0.05), considering that T1 and T3 primiparous lost weight. T1 and T2 had greater percentage of females showing estrus within 10 days after weaning/altrenogest withdrawal (94.1 and 95.0% respectively) than T3 (86.4%, P<0.05). The altrenogest withdrawal to insemination interval was smaller than T1 and T2 weaning to estrus interval (P<0.05). Farrowing rate and adjusted farrowing rate were higher (P<0,05) in T2 (94,3 and 95,7%) followed by T1 (87,0 and 88,0%) and T3 (69,1 and 69,1%). The number of total piglets born and alive were higher in T2 (13,5 ± 0,2 and 12,7 ± 0,2), followed by T1 (11,0 ± 0,2 and 10,4 ± 0,2) and T3 (9,8 ± 0.3 and 9,3 ± 0,3). There were body recovery and better reproductive performance in females breed at second estrus, besides being a viable technique in practice, as evidenced by high percentage of females showing second estrus. It appears that for a better performance in primiparous treated with altrenogest is necessary longer (12 to 18 days) period of treatment than five days. The weight loss due lactational catabolism persists after weaning as demonstrated by control and altrenogest treated group weight loss between weaning and insemination.

There has long been evidence for increased lipids in the liver of chickens exposed to feed restriction, commonly used for production hens. Lipogenesis is an important part of the metabolism and storing of glucose, a source of energy. Few studies compare the difference of lipids in the liver in chickens between regular feed restriction and skip-a-day diets, despite differences in lipid content found in other organs and in overall carcass. In this study I experimentally investigate if a difference in lipid content can be found in broiler breeders exposed to two different feeding regimes, 65 % feed restriction and 5:2 skip-a-day, along with the difference between days and time points (a.m. and p.m.). I also experimentally investigate the effect on dry weights of the liver. I expected to see a difference in lipids of the liver, with an increase found in skip-a-day birds. However, a difference could only be observed in the dry weights of the livers in birds exposed to skip-a-day feeding. Although there was no significant change in lipids, there is a pattern for increase in lipids in skip-a-day birds. Therefore, the conclusion can be drawn that an increase in lipogenesis caused by skip-a-day diet exists but it was not big enough to cause a significant difference in lipid content. For the dry weights of the livers, we can suspect lipids and glycogen as the reason for the increased weight but to determine exactly how these two components affect the skip-a-day birds’ further inquiry is needed.

The mechanisms of invazivity and regulation of transcription of cancer cells Cancer originates in cells that overcome the control mechanisms of the organism. Cancer cells can be eventually released from the site of origin and spread through tissues. Cancer cells can acquire certain mechanisms that enable them to more effectively invade surrounding tissue or layers of other cells. The research on the migration of cancer cells is important for the understanding of the origin and spreading of metastases and consequently for anticancer therapy. In my Ph.D. work, I participated in the research of the properties of invasive metastatic cells. We compared non-invasive rat sarcoma cell line with a higly metastatic cell line derived from it. We showed that cells of the invasive cell line use amoeboid mode of migration, have upregulated Rho/ROCK signaling, and have accumulated actin and myosin at the leading edge. It is at the leading edge where the cells generate their traction forces. Cells of non-invasive cell line use mesenchymal mode of migration and generate forces mainly at their retracting end. We also compared two breast cancer cell lines derived from a single carcinoma. We showed that the more invasive cell line, derived from its parental line by neoplastic transformation, displayed elevated cytoskeletal...