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Mining is an important economic sector that ensures continuous flow of income, employment, and business opportunities. Mining furthermore can promote education, improve health facilities, and improve community infrastructure. However, mining often causes undesirable impacts on biodiversity and the ecosystem services they underpin. This thesis presents results from a systematic review of the mining literature, historical analysis of satellite imagery, field-based biodiversity assessments and interviews with a wide range of stakeholders involved in mining operations and communities living within mining areas. Combined, these different approaches assess the environmental impacts of mining on biodiversity, ecosystem services, and the potential for restoration of mining landscape across the globe, and land use and land cover change through time and across space in Tanzania. Results from the systematic review revealed that, out of 2,093 studies reviewed, 99.8%, reported some form of negative impact of mining on biodiversity and ecosystem services. However, while 95% reported on the direct impacts, only 5% reported on the indirect impacts. Furthermore, out of 830 reviewed restoration studies, most focused on remediation experiments (43.9%, n = 364) while 26.3%, n = 216 focused on reclamation, 14.9%, n = 124 focused on rehabilitation and 14.9%, n = 124 focused on restoration. Results also revealed that commercial gold mines have escalated the rate of land cover changes and pulled illegal mining adjacent to mine leases. This is associated with impacts that manifest largely outside operational boundaries. This was observed in two older mine sites, where aboveground carbon and tree stem density are significantly higher within lease boundaries compared to outside, while there is no such effect at the new site. I recommend on rigorous, integrated impact assessments and conservation planning in mining landscapes to mitigate social and environmental impacts and balance outcomes across the mining sector to support livelihoods, development, and conservation agendas.

This study investigated quality faculty-student interactions, sense of belonging, self-efficacy for self-regulated learning, perceived responsibility for learning, academic achievement, and academic satisfaction. Participants (n = 898) included undergraduate students who identified as White, Black, and Latinx from a diverse university in the mid-Atlantic region. Path analysis revealed that relationships existed between contextual factors (i.e., quality faculty-student interactions, sense of belonging), self-regulated learning (i.e., perceived responsibility for learning and self-efficacy for self-regulated learning) and its outcomes (i.e., academic achievement and academic satisfaction). Self-efficacy for self-regulated learning and academic satisfaction fully mediated some relationships. Perceived responsibility for learning served as a partial mediator. ANOVA revealed that group differences existed for self-efficacy for self-regulated learning, academic satisfaction, and GPA. Educational implications and future directions will be discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Antibody-drug conjugates (ADCs) are an emerging class of anticancer agents which combine the cell-targeting properties of a monoclonal antibody and the cytotoxicity of a small molecule drug. The antibody, cytotoxin and the covalent linker which connects the two units must be optimised for the ADC to have favourable pharmacokinetic, toxicology, and overall pharmacological profiles. The first project describes the design, synthesis, and evaluation of vinylheteroarene linkers for the post-translational modification of proteinogenic cysteine residues. It was hypothesised that the variable heteroarene ring electronics would greatly affect the conjugate addition reaction rate and resulting bioconjugate stability. Thus, a panel of vinylheteroarenes with differing heterocyclic groups were synthesised and evaluated for their suitability. Using small molecule model systems, vinylheteroarene linkers were assessed for cysteine reactivity and chemoselectivity, and conjugate stability to identify the optimum linker. The lead linker was utilised to modify a number of protein substrates with various functionality, including the synthesis of a homogeneous, stable and biologically active ADC. The reagent was also efficient in labelling proteome-wide cysteines in cell lysates. The efficiency and selectivity of these reagents as well as the stability of the products makes them suitable for the generation of biotherapeutics or studies in chemical biology. The second project describes studies towards using (+)-discodermolide as a cytotoxic payload in ADCs. Discodermolide is a polyketide natural product which displays potent activity as an antimitotic agent and is known to be effective against a range of malignancy types. It was desired was to attach discodermolide to an antibody using a cleavable linker which would enable traceless release of the cytotoxin. The alcohol groups in discodermolide presented an opportunity to achieve this in a chemically tractable way. Thus, a valine-alanine-para-aminobenzylcarbonyl-hemiaminal linker was designed for the selective cleavage and payload release by lysosomal cathepsin enzymes. Importantly, this linker strategy allows the synthesis of linker-payloads in one synthetic step, making this a promising approach for the rapid assembly of ADCs using unexplored alcohol cytotoxins. Using this linker, a discodermolide ADC was successfully synthesised which can be used for biological evaluation.

The aim of this research is to determine Japanese first-year university students’ attitudes to and motivation for learning English. A successful English-language education system is crucial for Japan, under great pressure to internationalise during her most prolonged recession ever. To help make the education system successful, knowledge of learners’ attitudes and motivation is essential. Chapter 1 discusses Japan as a stage for English-language education. Japan is identified as uniquely homogenous and insular. Internationalisation of industry and a drop in the college-age population forcing universities to compete for students are identified as recent phenomena driving reform in the English-language education system. Chapter 2 describes the roughly 130-year history of Japanese English-language education from first contact to the present day. Changes in the English-language education policies of successive Japanese governments are discussed through examination of the Ministry of Education ‘Course of Study’ guidelines. Chapter 3 surveys the theoretical literature on attitudes and motivation in foreign and second language learning. Significant and relevant empirical research from Japan and other countries is reviewed. Chapter 4 determines an approach to the main research question through a number of subsidiary questions, using the theoretical framework from Chapter 3. A detailed research design (methods, schedule, and data collection procedures) is drawn up and discussed. Chapter 5 presents and analyses the findings of the two questionnaires which form the main data collection method. The computer program SPSS is used in analysis. Chapter 6 presents and analyses the findings of the two group interviews and two individual interviews by categorising and descriptive explanation. Chapter 7, the final chapter, reviews the research process and answers the subsidiary and main research questions. Key themes are that Japanese students are highly motivated to learn English for communication, and that the English classes currently offered at universities do not meet the demands of Japanese students. These answers and themes are used as the basis for some recommendations for English-language education in Japan.

This dissertation consists of three essays on adolescents' post secondary education choices and labor market returns. The first chapter analyzes returns to selectivity of four-year colleges by different post-bachelor's degree schooling paths. The second chapter documents the role of family income in college application and enrollment processes including college selectivity choices. The third chapter compares the option values of two-year colleges and four-year colleges for different levels of students' cognitive levels. Existing studies on the returns to college selectivity have mixed results, mainly due to the difficulty of controlling for selection into higher quality colleges based on unobserved ability. Moreover, researchers have not considered graduate degree attainment in the analysis of labor market returns to college selectivity. In the first chapter, I estimate the causal effect of college selectivity on wages including graduate degree attainment. I control for both observed and unobserved selection by extending the model of Carneiro, Hansen, and Heckman (2003). There are two channels through which college selectivity affects future labor market outcomes. The first is the wage returns to college selectivity conditional on graduate degree attainment. The second is the effect of college selectivity on the probability of graduate degree attainment and the wage returns to graduate degree attainment. The results show that graduating from a college of one standard deviation higher selectivity leads to a 3.7% higher hourly wage ten years after college graduation regardless of graduate degree attainment. In addition, a one standard deviation increase in college quality increases the expected returns to graduate degree attainment by 0.8% (4.3% increase in the probability of graduate degree attainment multiplied by 18.6% returns to a graduate degree). Recent studies document the increasing importance of family income in college enrollment probabilities over the past two decades in the United States. The second chapter further examines the role of household income in children's postsecondary institution application and enrollment decisions including college quality, using the high school classes of the early 2000s. I find that the family income is monotonically and positively correlated at the extensive margin of higher education (whether or not to apply and enroll in college) even when we control for children's cognitive ability. On the other hand, I find a U-shaped correlation at the intensive margin especially for four-year college students in terms of average applied, or enrolled, college quality after controlling for children's cognitive ability. These findings highlight different roles of the family income in college application and enrollment stages between extensive and intensive margins. In order to boost the number of skilled workers in the United States, policy makers are paying increased attention to the role of community colleges. Traditionally, researchers have studied community colleges in the context of vocational training, or as a budget friendly alternative for the first few years of a four-year college education. The third chapter examines the undocumented value of two-year colleges, namely, the option value incorporating the uncertainty in degree completion. The empirical results show that expected wages of enrolling at four-year colleges are strictly higher for all types of students than those of enrolling at two-year colleges. This is mainly because of the low associate's degree completion probability. These findings suggest that four-year colleges are strictly better than two-year colleges on expectations for all types of students. In order for two-year colleges to serve as a provider of wider options for individuals who have not yet decided whether to pursue a bachelor's degree, it is crucial to improve degree completion rates in these institutions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The cyclic enaminone lies at the core of this entire doctoral work. It possesses exceptionally versatile reactivities, and can thus be utilized in the synthesis of various alkaloids. The first chiral-pool approach to synthesize enaminones was reported in 2006 from the Georg group. However, partial racemization was observed in some cases. Also, homologated amino acids were synthesized or purchased as a starting material. To address these issues a novel strategy, that retained the use of amino acids was sought. We found that enaminones can be synthesized using a ketene cyclization. In this approach, a pendant enamine moiety underwent a nucleophilic addition to a ketene generated by the Wolff rearrangement of a diazoketone. The diazoketone can be synthesized from α-amino acid in a one-pot procedure. Although this approach utilizes α-amino acids and provides enantiopure enaminones, the solubility of amino acids as well as the use of diazomethane to prepare diazoketone became major obstacles to the scalable synthesis of various enaminones. In this regard, alternative methods to synthesize the diazoketones were explored. We found that diazoketones could be obtained from three readily available components: a primary amine, an alkyne, and bromo diazoacetone. Although the incorporation of chirality was not achieved, a wide variety of enaminones were synthesized in two steps from commercially available compounds, providing a facile access to an enaminone library. Enantiospecific syntheses of (–)-(5S,8R,9S)-5-(3-furyl)-8-methyloctahydroindolizin and its C8-epimer were accomplished using our enaminone chemistry. The devised synthetic routes are conventional but reliable and scalable, providing access to Nuphar alkaloids in 9 steps from N-Boc-(L)-proline. This work led to the correction of multiple prior publications. We were able to disclose the bindings of the major isomer to the central nervous system receptors. Although phenanthropiperidines are promising anti-cancer agents due to their potency, their neurological toxicities thwart therapeutic use. Assuming that the side-effects are caused by the blood brain barrier permeation of phenanthropiperidines due to their extremely lipophilic nature, endeavors to prepare a polar phenanthropiperidine library were made. Specifically, the synthesis of hydroxylated phenanthroquinolizidines was attempted. However, most of those compounds were found to be unstable.

The structure and mechanical behavior of Toco toucan (Ramphastos toco) and Wreathed hornbill (Rhyticeros undulatus) beaks were examined. The structure of Toco toucan and Wreathed hornbill beak was found to be a sandwich composite with an exterior of keratin and a fibrous bony network of closed cells made of trabeculae. A distinctive feature of the hornbill beak is its casque formed from cornified keratin layers. The casque is believed to have an acoustic function due to the complex internal structure. The toucan and hornbill beaks have a hollow region that extends from proximal to mid-section. The rhamphotheca is comprised of superposed polygonal scales (45 \[mu\]m diameter and 1\[mu\]m thickness) fixed by some organic adhesive. The branched intermediate filaments embedded in keratin matrix were discovered by transmission electron microscopy (TEM). The diameter of intermediate filaments was ̃10 nm. The orientation of intermediate filaments was examined with TEM tomography and the branched filaments were homogeneously distributed. The closed-cell foam is comprised of the fibrous structure of bony struts with an edge connectivity of three or four and the cells are sealed by the thin membranes. The volumetric structure of bird beak foam was reproduced by computed tomography for finite element modeling. The mechanical behavior of bird beaks was evaluated by tensile and compression testing. Micro and nanoindentation hardness measurements were used to corroborate these values. The mechanical response of toucan rhamphotheca exhibits isotropy whereas hornbill rhamphotheca may behave anisotropically in tension. The Young's moduli of toucan and hornbill rhamphotheca were found to be ̃1.0 GPa. The Young's modulus of rhamphotheca at high humidity condition dropped by a order of magnitude. The rhamphotheca exhibits a strain-rate sensitivity with a transition from slippage of the scales due to release of the organic glue, at a low strain rate, to fracture of the scales at a higher strain rate. The compressive strength of beak foam is dependent on the density. The higher apparent density of hornbill foam provides a four-fold higher strength than toucan foam. The mechanical behavior of beak skulls were modeled by the Gibson-Ashby constitutive equation. The compressive response of the beak revealed that there is a synergistic effect between foam and shell evidenced by the separate response of shell, foam, and foam + shell. The sandwich design of bird beaks were evaluated by the Karam-Gibson and Dawson-Gibson models. The models proved that the design of bird beaks was optimized for effectively achieving high resistance to buckling when they are subjected to bending rather than uniaxial loads. The synergistic interaction between foam and shell is also successfully confirmed by a finite element analysis (LS- DYNA). The foam stabilizes the deformation and prevents local buckling of the keratin shell by providing an internal support which increases its buckling load under compressive loading. The bending behavior of bird beak in finite element analysis was successfully compared with experimental results. The volumetric structure of bird beak foam was reconstructed in 3D by a visualization technique and this rendering was successfully applied to finite element calculations which predict compressive strength in agreement with experimental results.