VictorJuiz/thesis huggingface dataset:
Age-related changes in non-cognitive behaviours in a canine model model of aging and dementia and therapeutic evaluation of adrafinil and modafinil

The canine model of human aging and dementia has focused on cognitive aging with limited work on non-cognitive behaviours. The present investigation examined changes in non-cognitive behaviours in dogs as a function of age and cognitive ability. The therapeutic potential of two stimulants, adrafinil and modafinil, were also assessed. Locomotor activity was assessed using the open field test, the home cage test and the Actiwatchreg; system. Age-dependent declines were observed in a familiar situation using both the home cage test and Actiwatch reg; system. Cognitively impaired aged dogs, however, showed increased activity compared to unimpaired dogs. Dogs raised in a laboratory setting were hyperactive compared to dogs raised on a farm. The Actiwatchreg; demonstrated circadian patterns of activity in dogs that varied as a function of age, cognitive status and housing environment. Aged dogs housed in an indoor facility showed a delayed onset of activity and shorter, more fragmented bouts of activity compared to young dogs. Age-related differences were less prominent in dogs housed in an outdoor facility. The human interaction, model dog and silhouette tests assessed social responses. Young dogs displayed more active social responses including climbing and licking. The aged dogs preferred more passive responses such as sitting quietly beside the person. Cognitively impaired dogs exhibited very little interest in the social stimuli. Exploratory behaviour was assessed with the curiosity test. Interest in the toys declined with age with older dogs spending less time playing. Impaired dogs expressed little interest in the toys. Environmentally impoverished dogs showed high levels of interest in the toys independent of cognitive ability. The mirror test most reliably distinguished between cognitively impaired and unimpaired aged dogs. Impaired dogs spent the most time reacting to the reflection compared to other dogs. Adrafinil and modafinil are behavioural stimulants that we studied in aged dogs. Adrafinil most effectively increased locomotion in the novel open field test. Modafinil produced small increases in the open field test. No effect of modafinil was observed in the human interaction, curiosity or mirror tests. The canine model of human aging and dementia can therefore be extended to include non-cognitive behaviours and used to evaluate the therapeutic potential of pharmaceuticals and dietary interventions. (PsycINFO Database Record (c) 2016 APA, all rights reserved)
Regulation of alternative splicing during the cell cycle

Alternative splicing generates mRNA isoforms from a single precursor mRNA, and is thought to be a key step in generating proteomic diversity. Recent evidence indicates that transcriptional activators function in the regulation of splicing, however to what extent this occurs within the cell is unknown. Reported here are studies investigating the role of E2F1 in the constitutive and alternative splicing of endogenous target genes. Furthermore, global effects of E2F1 expression on alternative splicing, and the global regulation of alternative splicing during the human cell cycle were investigated using a novel microarray platform. The results of these studies provide evidence that E2F1 impacts the splicing of its target genes, and for the existence of cell cycle regulated alternative splicing events. These results set the stage for future studies investigating the mechanisms by which activators influence the splicing of target genes, and the possible roles of alternative splicing in cell cycle progression.
Regulation of axon growth by PTPsigma and its substrates N-cadherin and beta-catenin

PTPsigma belongs to the LAR-family of receptor tyrosine phosphatases, and was previously shown to negatively regulate axon growth. Using brain lysates from PTPsigma knockout mice, in combination with substrate-trapping, a hyper-tyrosine phosphorylated protein of sim;120kDa in the knockout animals was identified by mass-spectrometry and immunoblotting as N-cadherin. beta-catenin also precipitated in the complex and it is also hyper-tyrosine phosphorylated in the knockout mice. Dorsal root ganglia (DRG) neurons, which highly express endogenous N-cadherin and PTPsigma, exhibited faster rate of neurite outgrowth in the knockout mice relative to sibling controls when grown on laminin or N-cadherin substrata. However, when N-cadherin function was disrupted by an inhibitory peptide or lowering calcium concentrations, the differential growth rate between the knockout and sibling control mice was greatly diminished. These results suggest that the elevated tyrosine phosphorylation of N-cadherin in the PTPsigma( -/- ) mice likely disrupted N-cadherin function, resulting in accelerated DRG nerve growth.
Active reliable MultiConcast

Multicast and Concast are two important communication techniques in networking. In multicast, a sender is required to send only one message to multiple receivers. On the contrary, concast allows a receiver to receive only one message from multiple senders. Reliability mechanisms must be implemented to ensure that all the messages can be delivered properly. However, most reliability designs suffer from the problems of implosion, long packet recovery and session times. In order to solve these problems, this thesis presents a new reliable multicast and concast design called Active Reliable MultiConcast (ARMC). ARMC introduces a hop-by-hop design that allows message retransmission to take place immediately once message losses are detected. Moreover, ARMC provides three different error recovery schemes for routers within the network. Each router can choose a different scheme based on the transmission quality of its outgoing links. A prototype based upon ARMC has been built and its performance is evaluated in this thesis.
Techniques for timing closure on high-speed field programmable gate arrays

The Field Programmable Gate Array (FPGA) has become a popular implementation medium for digital circuits due to its ability to be configured to realize a variety of different circuits. Although the configurable nature of FPGAs is very attractive, circuits implemented in FPGAs are almost an order of magnitude slower than their ASIC counterparts. Thus it has become increasingly difficult for users to realize realistic timing constraints for FPGA implementations. This is usually referred to as the “timing closure” problem. This thesis investigates methods for achieving timing closure for FPGA based designs. Two main techniques are studied in this dissertation. The first studies the effects of creating arbitrary mappings between the logical and physical hierarchy of a design. This method has shown an average of 12% speed improvement when used to map critical sections of logic to fast physical regions on the target device. The second technique tightly integrates netlist optimizations with the placement and routing steps of the FPGA CAD flow. The circuit is restructured with a suite of timing-driven optimizations to better cope with the routing delays inherent in FPGAs. The suite of optimizations includes sequential retiming, Shannon's decomposition theorem, and clock skew optimization. Each technique is applicable, depending on circuit characteristics, or they may all be used in concert. These restructuring techniques have shown an average speedup of up to 25%.
Strengthening concrete slabs for punching shear with CFRP laminates

This paper reports on a new innovative approach for strengthening reinforced concrete slabs in shear with externally bonded CFRP laminates. An experimental study was carried out on twenty-eight square, isotropic two-way slab specimen; twenty-four of which contained CFRP laminate shear reinforcement. The experiment simulated conditions in the vicinity of an interior square column in a continuous flat plate structure. Parameters, such as the concrete strength, flexural capacity and shear reinforcement arrangement were investigated and the applicability of existing CSA23.3-94 standard specifications for punching shear resistance was examined. The slab specimens with CFRP laminate shear reinforcement demonstrated increases in shear strength of up to 83% over that of the control specimens and in some cases transferred punching shear to flexural failure. The increase in shear strength was accompanied by substantial increases in ductility and audible signs of distress. Further investigation into the behaviour of externally bonded CFRP laminate shear reinforcement under punching with moment transfer and cyclic loading is needed.
Structural and kinetic characterization of the Arabidopsis DHQ-SDH: The SDH catalytic mechanism and insights into the modes of substrate channeling and metabolism in the shikimate pathway

The shikimate pathway (SP) is comprised of seven enzymatic steps and is involved in the biosynthesis of the aromatic amino acids, folates, vitamins, quinones and a variety of other aromatic compounds in bacteria, plants, fungi and apicomplexa parasites. Some of the aromatic compounds are essential for the survival of these organisms; as a result, the shikimate pathway has been an attractive target for the design of antimicrobial and herbicidal agents. The Arabidopsis shikimate pathway enzyme, dehydroquinase-shikimate dehydrogenase (DHQ-SDH) catalyzes the dehydration of dehydroquinate to dehydroshikimate followed by the reduction of dehydroshikimate to shikimate (steps three and four of the SP, respectively). The bifunctional enzyme has been identified in plants and some microbes; however, the majority of microbes encode the monofunctional enzymes. This study is the first to report a crystal structure of a plant shikimate pathway enzyme, DHQ-SDH, in three substrate/ligand bound states: (1) Complex I - DHQ-tartrate-SDH-shikimate, (2) Complex II - DHQ-dehydroshikimate-SDH-shikimate, and (3) Complex III - DHQ-dehydroshikimate/tartrate-SDH-shikimate-NADP(H). The DHQdehydroshikimate-SDH-shikimate complexes reveal a possible mode for substrate transfer between the DHQ and SDH active sites. These findings have provided insight into the mechanism of substrate partitioning at this point in the SP. Moreover, a site-directed mutagenesis approach was taken to investigate the roles of the residues that interact with shikimate at the SDH binding site. Saturation kinetics profiles of these mutants revealed that the conserved Lys 385 and Asp 423 are important for the NADP-dependent oxidation of shikimate, whereas a number of residues are important for the binding and orienting of the substrate for efficient catalysis. This study into the SDH catalytic mechanism has also revealed a possible mode for substrate recognition for the different SDH homologs. Results have indicated that specific sequence motifs found within the SDH substrate binding site may confer substrate specificity in the SDH enzyme family.
Truth and hue: critical inquiry into the discourse of blackness

This thesis queries the complexity of hue in order to understand how racism when internalized, brings a form of self-regulation onto the accorded black body. The inquiry seeks to ascertain ways in which hue is interpreted as the 'Truth' and imputes the ethic of colonialism onto the body. The study is meant as a response to the question submitted by Frantz Fanon, "How do we extricate ourselves?" The thesis utilizes an anti-racism discursive framework and Michel Foucault's work on discourse, power and the subject to examine Frantz Fanon's Black Skin White Mask and Toni Morrison's Sula. The thesis is intended to inform anti-racism methodology, and also to imbue a sense of critical discernment on how hue and gender constitute the way in which social relations are experienced.

Keywords: Racism
Racism in language
Black race, Color
Blacks, Race identity
Hermeneutics and the reconstitution of universal memory

This study aims to disclose a vital theme of modern hermeneutical thinking: memory. The study examines the notion---found primarily in the hermeneutical writings of Hans-Georg Gadamer (d. 2002) and Paul Ricoeur (d. 2005)---that human memory plays an important, if not crucial role for self-understanding. According to these thinkers, memory is a catalyst for pedagogical reflection, more so than the emphasis upon "consciousness" which emerged in the early modern period of western philosophy with thinkers like Descartes and Kant. In the case of these enlightenment thinkers, the over-riding emphasis on the consciousness of the human subject, ensconced in the scientific concerns of the period, began to erase the more humanistic notion that history and memory were important for pedagogical prowess. It is in the scientific context of the enlightenment where we witness memory's polemical battle with an over-privileged concept of "consciousness:" first, with Giambattista Vico who battled with the mathematics and sciences of the Cartesians in Italy, and then, with Johann Gottfried Herder as he battled---more moderately---with Kant. With help from Hegel in the 19th century, Gadamer encourages a return to the scene of philosophy's main "methodological" error; its disengagement from almost all forms of pastness. He endeavors to return thought to a place where it had not yet lost its appreciation of the past: to a place where history and memory were once considered essential preoccupations of thought. It is to a dying remnant of the renaissance---alive in Vico---where the recovery of hermeneutical memory begins. However, the return to Vico's humanism marks only the beginning of an intellectual pilgrimage, which seeks a greater recollection within lost dialogue which lies at the heart of the hermeneutical process.
Children in the spotlight: emotional correlates of cooperative performance in early adolescence

It is generally recognized that emotions play a part in the adjustment of children to school. Less is known, however, about the relationship between emotions and cooperative performance, a crucial issue with today's greater emphasis on cooperative learning in the classroom. Participants for this comparative study were recruited from schools for the performing arts, a regular school's music programme, and a precision skating team, thereby sampling a range of commitment and expertise. During the week of stage production, adolescents (52 boys, 140 girls, ages 11-15) kept structured emotion diaries (Oatley & Duncan, 1994) which they filled out both before and after a final rehearsal, as well as before and after the actual performance. Proportions of positive versus negative emotions were significantly different as a function of performance condition, Q = 50.87, df = 3, p < .0001. Negative emotions in rehearsal were due to fatigue, boredom, fear of appearing foolish in front of peers, frustration with technical mishaps, or anger with authority figures for unreasonable directives or unfair criticism. Positive emotions after rehearsal or performance were, of course, contingent upon successful outcome. Prior to performance, adolescents were susceptible to anticipatory anxiety--highest for the most expert performers. For the performance process as a whole, however, happiness was by far the most frequently experienced emotion. This phenomenon is in accordance with Csikszentmihalyi & Larson's (1984) finding that arts and sports were the most intrinsically rewarding activities for teenagers. Performance groups differed significantly, not in pre-performance anticipation, but in post-event evaluation, chi2 (4, N = 178) = 52.85 and 70.88, respectively, ps < .0001. These results support Oatley's (1992) emphasis on cognitive evaluation in emotion and Gordon's (1990) distinction between factive and epistemic emotions. Performers were not overwhelmed by their emotions. On the contrary, they demonstrated a rational focus on issues central to their performance task. This finding is consistent with a goal-based theoretical position (Oatley & Johnson-Laird, 1996). Diaries reflected a pattern of progression from rehearsal to final production: Emotions appeared to be playing a functional role in the process of preparation, evaluation, and management of cooperative performance.

Keywords: Group work in education
Performance, Psychological aspects
Performing arts, Study and teaching (Elementary)
Performing arts, Study and teaching (Secondary)
Performing arts and youth
Emotions in adolescence
Knowledge, belief, and noisy sensing in the situation calculus

The extension to the situation calculus presented by Bacchus et al. formalizes the concept of noisy actions and shows how an agent can update its beliefs, which are modeled probabilistically, when relying on noisy sensors and effectors. The extensions of Scherl and Levesque and Shapiro et al. also model knowledge and belief. While assuming noiseless actions and dealing with boolean beliefs, these frameworks support properties of knowledge and belief such as introspection about current and past beliefs. Here, it is shown how such properties of belief can be formalized and supported in the probabilistic Bacchus et al. extension. In addition, the concept of sensor coarseness is introduced and it is shown how it can be modeled in the Bacchus et al. framework. Finally, it is shown that the Bacchus et al. framework can function in a way which is equivalent to using conditional probability densities to combine noisy sensor readings.
Genetic studies in inflammatory bowel disease

Introduction. A positive family history is the strongest known risk factor for the development of inflammatory bowel disease. Epidemiological data from familial and twin studies suggest genetic factors play an important role in the onset and course of inflammatory bowel disease. The objective of these studies is to evaluate the contribution of several biologically relevant candidate genes to phenotypic manifestations of inflammatory bowel disease. In addition, a study was conducted to assess the contribution of diagnostic misclassification on the ability to identify inflammatory bowel disease susceptibility loci. Methods. The first three studies utilized well characterized individuals with inflammatory bowel disease and selected polymorphisms in candidate genes to perform case-control association studies in order to ascertain the contribution of such polymorphisms to the phenotype of interest. The final study involved an assessment of the rate of diagnostic misclassification in an inflammatory bowel disease genetics study and a determination as to the impact of such misclassification on the ability to identify inflammatory bowel disease susceptibility loci. Results. Positive associations between alleles of selected human leukocyte antigen genes and the diagnosis of Crohn's disease, ulcerative colitis, colonic inflammatory bowel disease and diminished bone mineral density in inflammatory bowel disease patients were identified. An important allele implicated in susceptibility to sporadic colorectal neoplasia in selected populations was deemed not to have a role in the susceptibility to inflammatory bowel disease-associated colorectal cancer. Relatively low diagnostic misclassification rates were identified in patients enrolled in an inflammatory bowel disease genetics study, however, even these low rates resulted in a substantial loss of power to detect to detect true susceptibility loci. Conclusions. The identification of alleles associated with phenotypic characteristics of patients with inflammatory bowel disease will assist in attempts to identify those at risk for specific clinical features, in reducing clinical and genetic heterogeneity in inflammatory bowel disease assessment and provide information for further research into mechanisms of the occurrence of such phenotypes. Careful documentation of disease diagnosis and phenotypic manifestations is paramount in aiding the discovery of important susceptibility genes in inflammatory bowel disease.
Thyroid hormone deficiency due to preterm birth may hinder the development of colour vision

In development, thyroid hormone (TH) is essential for determining the pattern and distribution of photoreceptors across the retina, including the switch from S-opsin (responsible for blue-yellow vision) to M-opsin (responsible for red-green vision), known to occur during midgestation in humans. A deficiency of TH during pregnancy is thought to hinder this switch and result in longer RG latencies. To test this hypothesis, we employed a model of TH insufficiency based on preterm birth: the earlier an infant is born, the sooner it is cutoff from its maternal source of TH, the main TH supply during the first half of pregnancy and of continued necessity until birth. Our findings indicate a non-significant trend toward longer RG latencies in earlier born infants and correlations between TH and RG latency (longer RG latencies correlated with higher TSH levels). Our findings therefore support the theory that TH plays a role in colour vision development.
Induction of mitochondrial alternative oxidase during macronutrient stress decreases growth efficiency of tobacco cells

The impact of plant mitochondrial alternative oxidase (AOX) on the growth efficiency and carbon metabolism of tobacco (Nicotiana tabacum) was investigated. The carbon use efficiency (CUE) of wild type (WT) tobacco cells decreased from 0.50 under complete nutrient conditions to 0.19 and 0.29 under phosphate (P)- and nitrogen (N)-limited conditions, respectively. The drop in CUE in WT cells corresponded with a large increase in AOX respiratory capacity. Conversely, the CUE of transgenic tobacco suspension cells lacking AOX (AS8 line) remained approximately 0.50 under complete, low-P and low-N growth conditions. Under N-limitation, AS8 cells accumulated 2-fold more non-structural carbon (Cns) and 7-fold more sucrose than WT cells. Under P-limitation, AS8 cells incurred more oxidative damage than WT cells, as indicated by higher lipid peroxidation. In a series of growth chamber experiments, tobacco plants that over-express AOX had less biomass and Cns than WT plants when grown at high light.