VictorJuiz/thesis huggingface dataset:
The thermophysiology of uncompensable heat stress: influence of hydration status, fluid replacement, aerobic training, physical fitness, and heat acclimation

The present research was developed to investigate the separate and interactive influences of hydration status, fluid replacement, short-term aerobic training, heat acclimation, and aerobic fitness during exercise in the heat. The research focused on an uncompensable heat stress environment, where the capacity for evaporative heat loss is less than the amount required to maintain thermal steady state. This was produced by either light (3.5 km . h −1, 0% grade, no wind; Studies 1–3) or heavy (4.8 km . h−1, 4% grade, no wind; Study 1) exercise in the heat (40°C, 30% relative humidity) while wearing a multilayered clothing ensemble with a high insulative capacity and a low water vapour permeability. Study 1 investigated the influences of hydration status (euhydration versus hypohydration of 2.5% body mass), fluid replacement, and exercise intensity. Study 2 investigated the influences of short-term aerobic training and hydration status on unfit (LF) individuals. Study 3 investigated the influences of heat acclimation and hydration status on individuals of both LF and high fitness (HF). Hypohydration resulted in significant increases in cardiovascular and thermal strain and a decrease in exercise tolerance regardless of other factors. Fluid replacement decreased heart rate (fc) and increased tolerance time (TT) during fight exercise. In LF, two weeks of aerobic training or heat acclimation increased sweat rate (SR), but did not influence fc, rectal temperature (Tre), or TT. In HF, two weeks of heat acclimation increased SR, decreased [special characters omitted] and Tre, but did not influence f c or TT. Neither training nor heat acclimation in LF was able to increase TT to a level similar to that in HF before undergoing heat acclimation. A greater ΔTre over the course of the exercise was present in HF, through a combination of both a lower initial, and a higher endpoint, Tre. The higher endpoint Tre in HF was consistent regardless of hydration, training, or acclimation status. It is concluded that even mild hypohydration can significantly impair physiological responses and tolerance to exercise in an uncompensable heat stress environment, and that high aerobic fitness and habitual activity imparts a degree of protection that cannot be replicated by either short-term training or heat acclimation.
Models for safety analysis of road surface transit

The objectives of this study were to explore the development of zonal and arterial level collision prediction models that incorporate characteristics applicable to urban transit planning. A generalized linear modelling approach with a Negative Binomial regression error structure was employed using a dataset from Toronto, Canada. The zonal-level models indicate that vehicle kilometers traveled, bus or streetcar kilometers traveled, arterial road kilometers, bus stop density, stop location, and average posted speed have significant associations with transit-involved collision occurrence. The arterial-level models suggest that AADT, transit frequency, segment length, average stop spacing, presence of on-street parking, and stop locations have significant associations with collisions involving all motor vehicles. It is evident that these models can provide transit agencies with decision-support tools for considering safety implications in the strategic and service planning processes and to predict future levels of transit-involved collisions for an existing and a new transportation network or arterial route.
Computing hierarchical nonblocking discrete event systems

We develop two new procedures for the discrete event system (DES) software package TCT. Each is useful in the context of working with hierarchical DES, where 'high-level' model abstractions are used to synthesize control action for the original, more complex, 'low-level' plant. The first procedure tests whether or not a DES satisfies the observer property. If it fails to, then its high-level transition structure is modified so that it does. The second procedure tests a DES for the hierarchical nonblocking (HNB) property. When the test is inconclusive the original DES is modified to ensure this property. Each is accompanied by a thorough complexity study and examples to illustrate its utility. We also discuss the pros and cons of various HNB control architectures.
Interfacial equilibrium and dynamic properties of telechelic poly(ethylene oxide) end-capped by alkyl groups

Poly(ethylene oxide) end-capped with alkyl groups at both ends belongs to so called “telechelic polymers (TP)” and is widely used in industry as a rheology modifier in water-born coatings, in adhesives and sealants. Despite the fact that this polymer is used in heterogeneous systems in all industrial applications, its interfacial properties are not very well understood. We used the Surface Forces Balance (SFB) with shear capability to study the properties of thin layers of TP adsorbed to solid substrates from toluene and aqueous solutions. The equilibrium and dynamic forces in polymer layers were studied as a function of the nature of the solvent and the molecular architecture of the polymer. Our results show that in organic solvents providing good solvency conditions for poly(ethylene oxide) and alkyl groups the polymers adsorb as monolayers, whereas from aqueous solutions they form multilayers with properties of weak gels. The shear properties of these surface gels were studied as a function of confinement and shear velocity. The results reveal the lubrication effect of the surface gels similar to that observed for polymers in good solvency conditions. In addition, the adsorbed layers show a noticeable shear thinning effect.
Neutrophil tissue delivery, early immune protection and quality of life in neutropenia

The role of neutrophils in maintaining oral health has been well documented and is best understood when examining the poor oral health-related quality of life of children with neutropenia. Under normal conditions, the bacterial presence in the mouth is kept under control by a constant influx of neutrophils from surrounding periodontal tissues. This chemotactic recruitment of neutrophils to the oral cavity inspired us to develop and validate a non-invasive oral rinse assay to study the delivery of neutrophils to the mouth following chemotherapy and bone marrow transplantation (BMT), and to compare this information to circulating neutrophil levels, oral mucositis scores and infection-related fever episodes following blood neutrophil recovery. Using this oral rinse, we showed that oral neutrophils reappeared and returned to a stable level earlier in the mouth than in the blood following BMT, thus enabling us to successfully predict engraftment much sooner than it was evident in their blood counts as per the conventional definition of engraftment. Furthermore, the timing of neutrophil tissue delivery in the mouth was a good indicator of neutrophil functionality and infection susceptibility in the post-BMT setting. Consequently, we developed a mouse BMT model which uses enhanced green fluorescent protein-expressing donor neutrophils. Besides recapitulating the results from our human study, this mouse BMT model allowed us to better understand neutrophil recovery kinetics following transplantation and how they relate to the restoration of cellular immune function post-BMT. Using the model, we have demonstrated that protection against bacterial infection is conferred at the time of neutrophil tissue delivery which always occurs before neutrophils are detected in the blood. These findings reaffirmed the clinical utility of the oral rinse assay to predict engraftment and susceptibility to infection following transplantation. Moreover, the mouse BMT model served as an in vivo cell migration model to study the effectiveness of specific drug therapies on neutrophil recovery and functionality. This animal model has the potential to help us better understand the molecular mechanisms of neutrophil mobilization, and will allow us to begin to identify the biological determinants that influence the rate of neutrophil tissue penetration, their levels and survival in the tissues.
Ventral hindgut and bladder development

Developmental anomalies of the bladder pose a great challenge to pediatric urologists. Yet the mechanisms regulating the developmental biology of the bladder remain poorly understood. Bladder development involves epithelial-mesenchymal interaction. p63 is expressed in all stratified epithelia including the bladder urothelium. We have established that the N-terminal truncated isoform of p63, ΔNp63, is preferentially expressed in the ventral bladder urothelium during early organogenesis. p63-/- embryos embryos developed ventral midline defects affecting the ventral bladder and abdominal walls, reminiscent of bladder exstrophy, a congenital anomaly exhibited in human neonates. The p63 deficient ventral urothelium was neither stratified nor differentiated. It had significantly increased apoptotic activity and reduced cell proliferation. This is accompanied by failure to induce mesenchyme. Over-expression of ΔNp63 in p63-/- bladder primary cell cultures rescued the apoptosis. We conclude that ΔNp63 plays a crucial anti-apoptotic role during bladder development. The absence of ΔNp63 leads to ventral urothelial apoptosis, failure of mesenchymal development and bladder exstrophy. Shh is a candidate epithelial signal in the bladder epithelial mesenchymal interaction. The mechanism by which Shh regulates bladder development remains unclear. In the wild-type developing bladders, Shh was expressed in the epithelium whereas its transcriptional factor Gli2 and its target gene Bmp4 were expressed in the inner mesenchymal zone, which also contained more proliferating cells. In the outer mesenchymal zone, where Gli2 and Bmp4 expressions were not detectable, smooth muscle α-actin expression was detected. In Gli2 -/- embryo bladders, normal Bmp4 expression in the inner zone was lost. The normal radial pattern of inner zone of cell proliferation and outer zone of smooth muscle differentiation was replaced by disorganized cell proliferation and ectopic smooth muscle in the inner zone. Using primary murine bladder mesenchymal cell cultures, we demonstrated that transfection with ΔNGli2 adenoviruses up-regulated Bmp4 expression and addition of Bmp4 protein (10mg/ml) repressed smooth muscle differentiation. We conclude that Shh transcriptional factor Gli2 regulates the bladder mesenchymal patterning.
A posteriori finite element bounds: application to outputs of the three dimensional Navier-Stokes equations

An engineering design often focuses on optimizing the characteristic values of a system. These characteristic values, namely, ‘outputs’, for fluid mechanics or heat/mass transfer problems, may be average temperatures, mean concentrations, or average velocities of the underlying system, and can be expressed as linear functionals of the system's field variables, which are temperature, density, and velocities. For simulation based engineering design, the relevant system is modeled by partial differential equations (PDEs) which yield field variable solutions. The outputs of the system are functionals of the calculated field variable solutions. In this thesis, an a posteriori error estimation method is used to provide bounds to the linear functional output of the numerical solutions to the three dimensional Navier-Stokes equations. The Finite Element bound method is based on a domain decomposition technique for efficiently generating lower and upper bounds. The novelty of the research is to utilize the a posteriori error estimation method with Lagrange multipliers and the finite element tearing and interconnecting (FETI) procedure to extend the bound method to three space dimensions for Navier-Stokes (N-S) problems. The approach herein exploits a coarse mesh linearized N-S problem and demonstrates that the omitted nonlinear term is very small. The computational advantage of the bound procedure is that a single coupled nonsymmetric/symmetric large problem can be decomposed into several uncoupled symmetric small problems. A simple benchmark problem, which is selected here to illustrate the procedure, is to find the lower and upper bounds of the average velocity of a pressure driven, incompressible, steady Newtonian fluid flow moving at low Reynolds numbers through an endless square channel which has an array of rectangular obstacles. Numerical results from the three dimensional Navier-Stokes equations show that the bounds are sharp and that the required computational resources decrease significantly. Parallel implementation on a Beowulf cluster is also reported. The bound method has the potential to be an inexpensive and reliable approach to incorporate numerical simulation of large-scale engineering problems in engineering design.
Preparation, characterization and application of novel adsorbent from petroleum coke activated by sulphur dioxide

Activation of oilsands fluid coke by using sulphur dioxide was studied. Among the activation parameters, e.g., temperature, time, concentration, temperature is the most important. Specific surface area, as high as 360 m2/g compared to 7.5 m2/g of raw coke, was obtained after activation at 700°C for 12 h followed by acid washing. The mechanism of activation was studied by the SEM images and EDS analysis. Sulphur was found deposited on the newly created surface, resulting in high sulphur content (∼20% wt). The carbon and sulphur containing surface groups were studied by X-ray photoelectron spectroscopy. The adsorptive behaviours of activated coke and commercial activated carbon were compared. The adsorption capacities of activated coke for iodine, methylene blue, and mercuric ion are 330, 51 and 10.7 mg/g respectively. Besides surface area, porous structure and surface groups were found important as well.
Action-perception progress in tool-use development

Schlesinger and Langer (1999) found that children could use a tool to retrieve an out-of-reach object before they could visually discriminate an impossible tool-use event from a possible one. One problem with this study, however, involves the classification of children's tool-use proficiency, which could have misestimated children's tool-use ability. The aim of this study was to re-examine the action-perception progress of tool-use development using a more comprehensive coding scheme, while adding an additional condition that more completely assesses tool-use proficiency with regard to an action task. This study found that twelve and sixteen-month-olds showed more refined behaviors than 8-month-olds when using a hook to retrieve a toy, although, none of the age groups demonstrated true competency in hook-use. For the perception task, only the sixteen-month-olds discriminated the possible and impossible tool-use displays. Accordingly, this study replicated previous findings in certain aspects, while raising questions concerning action competencies precede perceptual abilities.
Getting ahead by getting along: How extraverted individuals attain social status by eliciting positive affect in others

Extraversion has been found to be the trait most predictive of social status in informal social groups, such as fraternities, sororities, and dormitories. One question arising from this research concerns how extraverted individuals attain social status. It was proposed that extraverted individuals attain social status by producing states of positive affect in others. This hypothesis was tested in first-year university students living in residence in households of four to six. Students rated themselves on the Big Five, rated each other's social status (prominence and influence) in the household, as well as rated how they typically feel (valance and activation) when interacting with each other. Extraverted housemates made household members feel happier in general, and household members rated extraverted housemates as the most prominent and influential members of their households. Discussion focuses on the implicated relations between extraversion, social status, and positive affect.
Shifting powers, mediating knowledge, and creating culture: a study of four students' online literacy practice for negotiating academic learning

This case study explores ways of encouraging students to showcase their background linguistic knowledge and technological expertise to collaboratively carry out academic discussions. Central to this thesis is a focus on how four students in a grade 10 Math class collectively construct knowledge and shape their social network in their group discussion via instant messaging (IM). The study is rooted in an integrated theoretical framework of Academic Expertise (Cummins, 2001) and sociocultural theories of mediated action (Wertsch, 1998) to examine the process of interactional learning of content, language, tools use, and social positioning. This study was conducted in a five-month semester. Within this period, IM was integrated into two group assignments and an exam review session. The group assignments instructed students to discuss mathematical concepts relating to linear systems and quadratic equations using IM in their groups to prepare for the writing of their individual 400-word essay. At the end of the semester, the groups were encouraged to participate in final exam review using IM with their teacher. Data for the study were derived from: (1) weekly classroom observations; (2) surveys of students' linguistic and ethnic backgrounds; (3) questionnaires pertaining to students' attitude toward Mathematics; (4) transcripts of students' online group discussions; (5) transcripts of online one-on-one and group interviews; (6) bi-weekly literacy surveys; and (7) student essays. The coding procedure followed Strauss and Corbin's (1990) threefold process. The study also relied on Mercer's (1995) work to define categories of emerging themes related to interaction of shared experience and knowledge. The findings suggest that IM and the literacy skills associated with its use are important components of learning when incorporated with classroom instruction. The students made use of IM to actively contribute to discussions through the protocol and structure of online communication that yielded positive outcomes in their academic learning. A pedagogical approach that places students' background knowledge and social realities at the forefront of learning empowered them to appropriate literacy skills associated with IM use to regulate learning. This approach resulted in the fostering of a safe environment wherein students enthusiastically engaged one another in academic work. (PsycINFO Database Record (c) 2016 APA, all rights reserved)
Characterization of Dok-R-mediated cell migration downstream of the receptor tyrosine kinase, Tek/Tie2

Tek/Tie2 is an endothelial cell receptor tyrosine kinase that induces cell migration upon Angiopoietin-1 (Ang1) stimulation. In conjunction with a phosphorylation state-specific antibody, a site-directed mutagenesis approach that mutated tyrosine residues on Tek was used that identified a unique interaction motif on Tek containing tyrosine residue 1106, an Ang1-dependent autophosphorylation site, which mediates binding to the phosphotyrosine binding (PTB) domain of the downstream of kinase-related (Dok-R) docking protein, leading to Dok-R phosphorylation. The pleckstrin homology (PH) domain of Dok-R further contributes to Tek binding in a phosphatidylinositol (PI)-3 kinase-dependent manner. A Tek mutant lacking tyrosine residue 1106 interferes with Dok-R phosphorylation in response to Ang1 in endothelial cells and cannot restore the migration potential of endothelial cells derived from mice lacking Tek. Together, these findings show that tyrosine residue 1106 on Tek is critical for coupling downstream cell migration signal transduction pathways with Angl stimulation in endothelial cells.
Understanding the mechanism of idiosyncratic drug reactions: Identification of the metabolic pathway leading to nevirapine-induced skin rash

Idiosyncratic drug reaction (IDR) refers to a kind of adverse drug reaction that does not occur in most patients at any dose and does not involve any known pharmacological properties of the drug. The mechanisms of most IDRs are unknown but the characteristics of these adverse reactions suggest that they are immune-mediated and circumstantial evidence strongly suggests that most are mediated by reactive metabolites. In this thesis, the focus will be on determining which reactive metabolite, if any, is responsible for a specific IDR; specifically nevirapine-induced skin rash.

Keywords: Toxicology
Pharmacology
Pharmacy
Synthetic applications of functionalized aziridines

This thesis contains three parts of research, all of which are focused on utilizing aziridines as the intermediates to synthesize valuable building blocks or bioactive structures. The aziridine functionality, a three-membered ring structure containing a nitrogen atom, is widely used in synthesis for chemical bond elaborations and functional group transformations. The most important synthetic application of aziridines is their ring opening reactions which take advantage of strain in the three-membered ring. Other special properties such as oxidative stability or weak basicity have seldom been considered as the rationale for synthetic methodology development or utilized in synthetic route design. In the first part of this thesis, the oxidative stability of aziridines was utilized to carry out a sequence of cyclization and aziridine-opening transformations. The process provides straightforward synthetic entries into a range of larger heterocyclic structures (such as five-membered ring pyrrolidine or six-membered ring piperidine) which are often found in the bioactive natural products or pharmaceuticals. This methodology is of significance in term of generating libraries of the nitrogen heterocycles. The broad scope of substrates used in this research demonstrates the potential value of this methodology. The second part of this thesis deals with an application of the above methodology towards the natural product ficellomycin. Ficellomycin is a naturally occurring antibiotic which shows in vivo antibacterial activity. Due to its rare chemical structure, no successful total synthesis has been reported. We noticed that our aziridine cyclization methodology can be applied to the synthesis of ficellomycin. In this thesis, two synthetic approaches were developed to construct the core structure of ficellomycin. The control of the relative stereochemistry provides an opportunity to synthesize the diastereomeric analogs of ficellomycin. In the third part of the thesis, synthesis of allyl amines from 2-ketoaziridines has been studied. Allyl amine structures are often found in natural products and pharmaceuticals. The hydrazinolysis of 2-ketoaziridines were found to afford allyl amines and pyrazoles. The reaction condition was optimized. The electronic and steric effects from the substituents were studied. A variety of 2-ketoaziridines were transformed into diversely substituted linear or cyclic allyl amines in good yields using this methodology.