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This dissertation studies China’s energy policy since the “Go Out” strategy became the PRC’s “overarching national strategy”, having been put forward for the first time in the 5th Plenum of the 15th CPC Central Committee in October 2000 –despite having been de facto implemented since 1993. It focuses on the evolution of the PRC’s petroleum and biofuels policy from 2000 to 2010 and on the impact it has had on Brazilian and Argentine energy policy and exports of energy resources to China. The study adopts an asymmetrical interdependent perspective within a South-South Cooperation analytical framework to argue that the role these countries have played as suppliers of fossil energy resources (petroleum) to the PRC throughout the observed period –role that can be defined as having been relatively modest in spite of having ranked as China’s top South American oil suppliers for most of it– has considerable potential to become significantly more relevant in the future, through the diversification of their energy exports to China based on the combination of fossil fuels and renewable energy resources (biofuels). As regards the former, the study highlights the game-changing discovery of enormous ultra deep-water off-shore reserves in Brazil in 2007 and 2010 (Tupi-Lula and Libra, respectively, which are already turning Brazil into a major oil exporter) and of the gigantic shale energy formation of Vaca Muerta in Argentina in 2010. Regarding the latter, both Brazil and Argentina are leading producers and exporters of biofuels (sugar cane- based ethanol and soybean-based biodiesel, respectively). The remarkable progress that the PRC has made in the energy sectors of the analyzed countries –and in Latin America in general, showing the “asymmetry of attention” paid by China and the USA to the region is emphasized. The research highlights the increasing importance that renewable energy resources are having in Chinese energy policy, due to both energy security and environmental concerns. It argues that the addition of clean energy resources to their exports to the PRC would benefit Brazil and Argentina by allowing them to diversify not only their export baskets (by adding more products to their exports to China, with the plus that these would have value added) and export destinations (adding the growing Chinese market while simultaneously reducing these countries’ dependence on traditional biofuel destinations such as the EU and the USA), but would also have positive effects for China’s fuel supply mix, contributing to make China’s transition to a low-carbon economy (or, at least, lower-carbon) shorter – as well as positive spillovers in their industrial structures.

This study determined the effect of N-acetylcysteine (NAC) supplementation on recovery of strength following eccentric muscle injury. Female subjects (n = 21, age = 20.7 ± .10 yr, weight = 68.05 ± 10.3 kg, height = 1.69 ± .07 m) performed one bout of eccentric exercise involving the forearm flexor muscles. Subjects were given a placebo (food-grade cellulose; n = 10) or NAC supplement (10 mg·kg-1 bw·d-1; n = 11) for 7D prior to and 14D following the exercise bout. Maximal Voluntary Contraction (MVC) torque, muscle soreness, range of motion (ROM), and arm circumference were measured at pre-exercise, immediately post-exercise, and at 1D, 3D, 7D and 10D post-exercise. In addition, serum interleukin-6 (IL-6), serum creatine kinase (CK), and serum glutathione were measured. Subjects also completed a food frequency questionnaire to determine the antioxidant content of their diet. There was no difference in the loss and subsequent recovery of muscular strength between the placebo and NAC group immediately post-exercise (26.93 ± 6.4 vs. 24.95 ±9.4 Nm), 1D (27.83 ± 5.7 vs. 26.9 ± 8.5 Nm), 3D (38.35 ± 6.7 vs. 34.69 ± 10.2 Nm), 7D (46.9 ± 8.8 vs. 42.5 ± 11.8 Nm), or 10D (57.83 ± 11.7 vs. 52.92 ± 14.3 Nm) post-exercise (p = .274). In addition, there was no difference in muscle soreness (p = .752), arm circumference (p = .535), ROM (p = .539), serum CK (p = .449), serum glutathione (p = .967), or serum IL-6 (p = .360) at any time point. Scores on the food frequency questionnaire demonstrated that dietary antioxidant intake was not different between groups (41.04 ± 8.04 vs. 33.01 ± 12.6; p = .054). In conclusion, a bout of eccentric forearm flexor exercise resulted in muscle injury and a significant decrease in subjects’ ability to produce force. Supplementation with NAC had no effect on recovery of strength, arm circumference, ROM, serum CK, serum IL-6, or serum glutathione at any time point following the exercise bout. These results demonstrate that NAC has no effect on recovery of strength following eccentric muscle injury.

Glycosylation, the addition of sugar moieties to nascent proteins, is one of the most common posttranslational modifications. Glycosylation regulates protein structure, function and localization. Most cell surface proteins and secreted proteins are glycosylated by the addition of Asparagine(N)-linked glycans (N-glycans). Aberrant N-glycosylation is a well-accepted feature of malignancy and is a potential prognostic marker for some types of cancer. For example, increased expression of complex N-glycans has been detected in cancers of breast, colon and has been correlated with reduced survival of the patients. Therefore, understanding the role of N-glycosylation in malignancy could be beneficial for developing novel therapeutic and prognostic strategies. To examine the role of N-glycosylation in malignancy, we applied chemical biology and genetic approaches. First, we conducted a high throughput screen to identify compounds that could block L-PHA-induced cell death. Our screen identified the cardiac glycoside Na+/K+-ATPase inhibitors as novel inhibitors of N-glycosylation. Further analysis of N-glycans consistently confirmed that inhibition of Na+/K+-ATPase impairs the N-glycosylation, as well as migration and invasion. Interestingly, other studies have shown antimetastatic effects of cardiac glycosides in patients. Thus, our high throughput screen identified Na+/K+-ATPase inhibition as a novel strategy to target the N-glycosylation pathway. In addition, we used a genetic approach to investigate the role of N-acetylglucosaminyltransferase I (GlcNAc-TI/Mgat1) in malignancy. Knockdown of GlcNAc-TI decreased the cell-surface expression of complex N-glycans. By confocal microscopy, knockdown of GlcNAc-TI decreased cell surface expression of β1 integrins and increased their localization around the nucleus. Moreover, GlcNAc-TI knockdown decreased the migration and invasion of malignant cells. Next, we investigated the effect of GlcNAc-TI in an orthotopic xenograft mouse model of metastasis. GlcNAc-TI knockdown significantly decreased the lung colony formation of the highly metastatic PC3N7 human prostate cancer cell line in mice. Our results suggest an important role for GlcNAc-TI in tumor metastasis. Interestingly, breast cancer patients with lower expression levels of Mgat1 had lower risk of disease relapse after therapy. Thus, GlcNAc-TI plays an important role in cancer progression and metastasis and GlcNAc-TI inhibitors could have therapeutic benefits for cancer patients. Moreover, expression levels of GlcNAc-TI could be used as a prognostic marker in patients with cancer.

Measures of working memory capacity are associated with performance on a variety of cognitive tasks. A number of recent studies have provided evidence that training working memory can lead to improvements in fluid intelligence and performance on other untrained tasks. However, many of these studies suffer from design limitations. The aim of this study was to investigate the effects of working memory training on measures of fluid intelligence, reasoning, working memory, and attentional control by comparing a training group with an active control group. The training group improved more than the active control group on some, but not all outcome measures. Differential improvement for the training group was observed on fluid intelligence, working memory capacity, and response times on conflict trials in the Stroop task. In addition, individual differences in pre-training fluid intelligence scores and initial performance on the training task explain some of the variance in outcome measure improvements.

Nitrogen fertilization has the potential to significantly affect yield, nutrient concentration and removal and overall stand longevity of C4 grasses grown for bioenergy production. While most studies report that these grasses need little to no fertilizer inputs to maximize yield, no specific recommendations have been given for fertilizer requirements across a wide range of C4 perennial grass species, cultivars, harvest timings and N application rates. Two field trials were established in the summer of 2008 in Ridgetown and Elora, Ontario to compare 4 Miscanthus (M. sinensis and M. sacchariflorus crosses; Nagara-116 and Amuri-114, and Miscanthus x giganteus; M1 Select and Polish), 2 switchgrass (Panicum virgatum L.; Cave-in-rock and Shelter) and 2 big bluestem varieties (Andropogon gerardii Vitman; Prairie view and Southlow), 4 nitrogen fertilization rates (0, 40, 80, and 160 kg N ha-1) and 2 harvest timings (fall vs. spring harvest). Plots were harvested in the fall of 2009 and spring and fall of 2010. Yield response to N fertilization varied by location, species and year. In general, increasing N fertilization rates generated an increased yield response in all tested species. Different rates of N fertilization resulted in variable responses to N, P and K tissue concentrations and removal in switchgrass and Miscanthus. Tissue N concentrations and removal both increased with added N fertilization at both locations. In most cases N removal was the highest at the highest N application rate. Nitrogen concentrations were highest in the leaves and seed heads across species, N rates and locations. P and K concentrations and removal with increasing N fertilization in the whole plant and in individual plant parts did not follow clear trends in either Miscanthus or switchgrass in both locations. Delaying harvest to spring reduced yield at both locations by 35-42% and 62-65% for Miscanthus and switchgrass, respectively. Yield losses by delaying harvesting to the spring were increased with higher rates of N fertilization. Delaying harvesting decreased N, P and K concentration and removal in most grasses and locations.

Carbohydrates constitute the most abundant class of natural products in the living world and they play various roles. They are notably involved in cell-cell interactions and immune reactions. It has been observed that tumor cells express, on their surface, unusual oligosaccharides named Tumor-Associated Carbohydrate Antigen (TACA). One TACA of interest to our research group is the Lewis A Lewis X hexasaccharide that is displayed on the surface of squamous lung carcinoma cells. Since carbohydrates are involved in immune reactions and can be recognized by antibodies, it becomes possible to design a carbohydrate-based vaccine against these tumor cells. This thesis describes the total synthesis of the TACA Lewis A Lewis X hexasaccharide and the preparation of two fragments: one tetra- and one pentasaccharide. These molecules were prepared as hexyl and aminohexylglycosides. In addition, the hexasaccharide was synthesized as a disulfide. This diversity of these synthons will allow conjugation to a protein, analysis by nuclear magnetic resonance techniques, and immobilization on gold of the antigen. Without doubt, this work is a significant contribution to the development of an anti cancer vaccine as it constitutes the first stage of the process.

Omega-3 polyunsaturated fatty acids (PUFA) and vitamin D both have anti-cancer effects through common and unique pathways. The hypothesis of this thesis is that the combination of n-3 PUFA with 1,25(OH)2D3 will inhibit breast cancer cell growth in an additive or synergistic manner. A 3X3 factorial design was used to test the combinations of five PUFA treatments (α-linoleic acid (ALA, 18:3n3), eicosapentaenoic acid (EPA, 20:5n3) and docosahexaenoic acid (DHA, 22:6n3), γ-linolenic acid (GLA, 18:3n6) and arachidonic acid (AA, 20:4n6)) with 1,25(OH)2D3 on MCF-7, MDA-MB-231, and MCF-10A cell growth, and determine any potential synergism in combination treatments. MCF-7 and MCF-10A cells responded to PUFA and 1,25(OH)2D3 treatments, but combinations provided no potential synergism. MDA-MB-231 growth was not affected by 1,25(OH)2D3, while combinations treatments involving ALA, EPA, GLA, and AA caused potentially synergistic growth inhibition. This thesis presents the novel observation that PUFA are sensitizing MDA-MB-231 cells to 1,25(OH)2D3 treatment.

Bioactive food components containing n-3 polyunsaturated fatty acids (PUFA) and curcumin modulate multiple determinants that link inflammation to cancer initiation and progression. In this dissertation, both transgenic and dietary mouse models were used to elucidate the effect of n-3 PUFA and curcumin treatment on murine intestinal inflammation. Specifically, fat-1 transgenic mice, which convert endogenous n-6 PUFA to n-3 PUFA in multiple tissues, exhibited a reduced number of colonic adenocarcinomas per mouse (1.05 plus/minus 0.29 versus 2.12 plus/minus 0.51, P = 0.033), elevated apoptosis (P = 0.03), and a decrease in n-6 PUFA–derived eicosanoids compared with wild-type (wt) mice in an azoxymethane (AOM) - dextran sodium sulfate (DSS) model. Following a 2-week recovery period after 5 days of DSS exposure, colonic inflammation and ulceration scores returned to pretreatment levels only in fat-1 mice. In addition, fat-1 vs wt mice exhibited decreased (P < 0.05) levels of CD3 , CD4 T helper, and macrophage cell numbers in the colon. The ability of n-3 PUFA to favorably modulate the resolution of intestinal inflammation in fat-1 mice was linked to an enhancement (P < 0.05) in the percentage of colonic lamina propria (cLP) CD4 FoxP3 cells and a decrease in both splenic and cLP Th17 cells (0.8 vs 1.2 percent in spleen, 1.4 vs 1.7 percent in colon) (P < 0.05) in fat-1 mice compared to wt. These results suggest that the antitumorigenic effect of n-3 PUFA may be mediated via its anti-inflammatory properties. The combined effect of n-3 PUFA and curcumin on DSS induced colitis was assessed in C57BL/6 mice. Addition of fish oil (FO) and/or curcumin to a corn oil (CO) based diet increased animal mortality compared to CO alone (P < 0.05). Consistently, following 1 or 2 cycles of DSS treatment, both dietary FO and curcumin promoted mucosal injury/ulceration compared to CO. However, compared to other diets, FO and curcumin combined feeding enhanced the resolution of chronic inflammation and suppressed (p < 0.05) a key inflammatory mediator, NF-kB, in colon mucosa. Mucosal microarray analysis revealed that dietary FO and curcumin differentially modulated the expression of genes induced by DSS treatment. These results suggest that dietary lipids and curcumin interact to regulate mucosal homeostasis and the resolution of chronic inflammation in the colon.