Designed for the protection of major agricultural crops, neonicotinoids are the fastest-growing class of insecticides used against a broad spectrum of insect pests. Although neonicotinoid toxicity toward non-target organisms (e.g., bees, aquatic insects) has been well-studied, less is known about their distribution of use, transport, and fate in North American agroecosystems. This is especially true of neonicotinoid interactions with wetlands in the Canadian Prairies. Between 2009 and 2012, neonicotinoid use as a seed treatment increased by 30% across the Canadian Prairies. During spring 2012 to spring 2013, I sampled water and sediment from 136 wetlands situated in a range of crop types across central Saskatchewan to determine the extent of neonicotinoid contamination. Wetlands situated in oat, canola, and barley fields consistently contained higher neonicotinoid concentrations in water than in grasslands, but no single crop influenced overall detections. Neonicotinoid detections in water varied from 16% (fall 2012) to 91% (spring 2013) with peak concentrations up to 3110 ng/L found in summer. I found numerous detections of neonicotinoids in spring, after ice-off, but before seeding. Through sampling snow, snow meltwater, and soil particulates from previously treated (clothianidin) and untreated fields, meltwater showed the strongest relationship to initial spring concentrations in wetland water. Neonicotinoid concentrations increased with time in shallow temporary wetlands which appeared most at risk for annual contamination. While snowmelt contamination influenced water concentrations in spring, peak concentrations in wetlands were consistently found during summer sampling completed in 2012-2014. Rapid wetland assessments completed on 238 wetlands (summer of 2012 and 2013) revealed key ecological, hydrological and landscape features that influenced neonicotinoid detections and peak concentrations in Prairie wetlands. The results of my exploratory analysis indicated that plant community composition is a key indicator and/or driver of both detection and concentration of neonicotinoids in Prairie wetlands. In particular, specific shallow marsh plants were commonly associated with either higher (e.g., Scirpus validus) or lower (e.g., Mentha arvensis) neonicotinoid concentrations in natural wetlands suggesting wetland macrophytes in this zone may be either indicators of agricultural disturbance intensity or differentially capable of accumulating the insecticide in its tissue. Therefore, in 2014, I conducted an outdoor microcosm experiment to evaluate thiamethoxam uptake from water by Typha latifolia and Alisma triviale using two concentrations over a 7-day period. Experimental results found some trace positive detections but no quantifiable accumulation of the insecticide in plant tissues. This is despite the fact that results of my 2015 field study found species of Typha, Alisma and Equisetum had neonicotinoids more frequently detected in their tissues, at concentrations ranging from 1.01-8.44 ug/kg. My findings demonstrate that neonicotinoid distribution and fate in Canadian Prairie agroecosystems is driven by interactions between ecological, hydrological, and landscape characteristics. Consequently, these drivers regulate neonicotinoid exposure and persistence in ecologically important regional wetlands. In order to effectively conserve these critical waterbodies, conservation planning should consider the importance of maintaining naturally diverse vegetation zones to mitigate insecticide exposure to wetland-dependant organisms.

This paper investigates the determinants of intra-year error in annual effective tax rate estimates, relative to the actual annual effective tax rate (“ETR Miss”) and examines whether ETR Miss contains value relevant information. I find that ETR Miss is affected by both unbiased estimation errors related to the predictability of business fundamentals and biased estimation related to varying managerial incentives within the year. Firms with higher ETR Miss exhibit less persistent pre-tax earnings and earnings components, consistent with ETR Miss containing information on earnings quality. Finally, for firms with higher ETR Miss, investors place a lower weight on accounting earnings, consistent with the market incorporating information in ETR Miss for valuation assessments.

abstract: Increasing numbers of courses are offered online and increasing numbers of students are pursuing post-secondary studies. At broad-access institutions, such as land grant universities and community colleges, this presents a particular concern around student persistence--that is, the number of students who complete diploma, certificate, or degree requirements from an institution. Such increased access and increased enrollment also present unique challenges to first-year writing instructors, who are often the first professionals with whom first-year students are in contact. Here I explore the many reasons why student persistence should interest first-year writing instructors, in particular, those who are teaching online. Student persistence has important civic, economic, ethical, institutional, and disciplinary implications that first-year instructors cannot ignore. I propose a persistence-based pedagogy that involves six essential elements: designing learner-centered online writing courses, demonstrating mattering by valuing student writing, fostering self-efficacy by making assignments relevant, fostering student connections through collaboration and community, engaging virtual learners by fostering a sense of place and presence, and recognizing the challenges and minimizing the risks of teaching online. Such an undertaking is necessarily transdisciplinary and draws on scholarship in rhetoric and composition, instructional design, educational psychology, applied linguistics, and higher education administration. It connects pedagogical principles advanced nearly fifty years ago with digital pedagogies that are in their infancy and attempts to balance the social epistemic nature of writing instruction with the real-world demands of diverse student populations, increasing course sizes, and ever-changing technologies. Perhaps most importantly, this dissertation focuses on strategies that online writing instructors can adopt regardless of their theoretical leanings, academic training, or institutional requirements. While persistence-based instruction does not change the purpose or outcomes of first-year composition and does not replace proper placement measures or address early-term drop rates, it does provide a framework for facilitating online courses that is rooted in rhetorical theory and composition pedagogy and promotes informed teaching and lifelong learning. / Dissertation/Thesis / Ph.D. English 2012

abstract: Existing literature consistently documents a relationship between book-tax differences and future financial performance. Specifically, large book-tax differences are associated with lower earnings persistence. I contend that one reason the tax information contained in financial statements is informative about future earnings is that the relationship between book income and taxable income captures information about a firm's life cycle stage. Using a life cycle measure from the literature, I use fundamental analysis to group firm-year observations into life cycle stages and document a link between book-tax differences and firm life cycle. I build on prior studies that find a relation between earnings persistence and book-tax differences, and earnings persistence and firm life cycle. I find that after controlling for firm life cycle stage, the association between large positive book-tax differences and lower earnings persistence does not hold. My results offer an economic theory based explanation for the relation between book-tax differences and earnings persistence as an alternative explanation to findings in prior research. / Dissertation/Thesis / Ph.D. Accountancy 2012

Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-08-14T14:27:22Z No. of bitstreams: 1 AlannaOC_DISSERT.pdf: 1206940 bytes, checksum: 16d4953440e825979cbfcb54a963a7cd (MD5) / Made available in DSpace on 2017-08-14T14:27:22Z (GMT). No. of bitstreams: 1 AlannaOC_DISSERT.pdf: 1206940 bytes, checksum: 16d4953440e825979cbfcb54a963a7cd (MD5) Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The knowledge of the factors related to the dynamics of herbicides in the environment it’s fundamental importance to predict the behavior of herbicides in soils with different attributes and to the selection of suitable dosages, and to avoid detrimental effects on the environment and on subsequent crops. The use of plants can aid in the remediation of the contaminated soil, and the herbicide tolerance is an essential factor for the species used. The objective of this work was to evaluate the sorption and desorption for a better understanding of soil ametryn behavior and to select plant species for remediation programs in areas contaminated with the herbicide. In the determination of sorption and desorption, the “Batch Equilibrium” method was used to determine the equilibrium time of ametryn in eleven soils with different attributes. In the sorption test the ametryn solutions (0, 1, 2, 4, 8, 16, 24 and 32 mg L-1) prepared in CaCl2 0,01 mol L-1 were added 10mL to samples of 200g of soil, shaken for 4 hours. The Desorption was evaluated using tubes containing a concentration of 16 mg L-1 before the sorption test, to which were added 10 mL of the solution of CaCl2 0,01 mol L-1 without herbicide. All the supernatants were filtered and the concentration of the herbicide analyzed by high performance liquid chromatography. The selection of ametryn tolerant species was performed by means of two experiments. In the first one the tolerance of the twenty seven species was evaluated to half of the recommended dose of the herbicide (1.000 g ia ha-1). In the second experiment, the selected ones were submitted to three different doses of the herbicide (0, 1000 e 2000 g i.a ha-1). The results showed that the sorption was higher in soils with high organic matter content and higher ion exchange capacity.The ametryn caused the death of Leucaena leucocephala, Crotalaria juncea, Crotalaria ochoroleuca, Fagopyrum tataricum, Mimosa caesalpiniaefolia, Arachis pintoi, Crotalaria spectabilis, Pennisetum glaucum, Glycine max, Calopogonium mucunoides, Mucuna pruriens, Vigna unguiculata, Phaseolus vulgaris, Sesamum indicum e Gossypium hirsutum. Canavalia ensioformis was tolerant until to dose 1000 g i.a ha-1 of ametryn. Cajanus cajan and Brachiaria decumbens until to dose 2000 g i.a ha-1 and present potential for inclusion in the remediation program of this herbicide / O conhecimento dos fatores relacionados à dinâmica de herbicidas no ambiente é de fundamental importância para prever o comportamento destes em solos com diferentes atributos e para selecionar de dosagens adequadas, bem como evitar efeitos prejudiciais ao ambiente e às culturas subsequentes. O uso de plantas pode auxiliar no processo de remediação dos solos contaminados, sendo que a tolerância ao herbicida é fator essencial para a espécie utilizada. O objetivo deste trabalho foi avaliar a sorção e dessorção para o melhor entendimento do comportamento do ametryn no solo e selecionar espécies vegetais para programas de remediação de áreas contaminadas com o herbicida. Na determinação da sorção e dessorção foi utilizado o método “Batch Equilibrium” para determinar o tempo de equilíbrio do ametryn em sete solos com diferentes atributos. No ensaio de sorção foram adicionadas 10 mL das soluções de ametryn (0; 1; 2; 4; 8; 16; 24 e 32 mg L-1) preparadas em CaCl2 0,01 mol L-1 a amostras de 2,00g de solo, submetidas a agitação por 4 horas. A dessorção foi avaliada utilizando os tubos que continham a concentração de 16 mg L-1 antes do ensaio de sorção, a estes tubos foram adicionadas 10 mL da solução CaCl2 0,01 mol L-1 isenta de herbicida. Todos os sobrenadantes foram filtrados e a concentração do herbicida analisada por cromatografia liquida de alta eficiência. A seleção de espécies tolerantes ao ametryn foi realizada por meio de dois experimentos. No primeiro avaliou-se a tolerância das vinte e sete espécies a metade da dose recomendada do herbicida (1.000 g ia ha-1). No segundo experimento, as selecionadas foram submetidas a três doses diferentes (0, 1000 e 2000 g i.a ha-1) do herbicida. Os resultados demonstraram que a sorção foi maior em solos com alto teor matéria orgânica e maior capacidade de troca iônica, enquanto que a dessorção foi inversamente proporcional à sorção. O ametryn causou a morte de Leucaena leucocephala, Crotalaria juncea, Crotalaria ochoroleuca, Fagopyrum tataricum, Mimosa caesalpiniaefolia, Arachis pintoi, Crotalaria spectabilis, Pennisetum glaucum, Glycine max, Calopogonium mucunoides, Mucuna pruriens, Vigna unguiculata, Phaseolus vulgaris, Sesamum indicum e Gossypium hirsutum. Canavalia ensioformis foi tolerante até a dose 1000 g i.a ha-1 do ametryn e Cajanus cajan e Brachiaria decumbens até a dose 2000 g i.a ha-1 e apresentam potencial para inclusão em programa de remediação deste herbicida / 2017-08-14

Cette thèse analyse les déterminants et les implications de l’innovation tout en mettant en relief la complémentarité entre les compétences technologiques et organisationnelles et leur accumulation dans le temps. Notre étude économétrique est basée sur les données de trois vagues de CIS françaises (1998-2006). En premier lieu, nos résultats suggèrent que l’innovation est déterminée par les caractéristiques internes et externes de l'entreprise. En outre, les tests de complémentarité ont montré que pour pouvoir bénéficier pleinement de l'effet positif du partenariat et des efforts de R&D sur l'innovation, ceux-ci doivent être accompagnés par une architecture organisationnelle favorisant la création et le partage des connaissances. En deuxième lieu, nos résultats montrent que les innovations surtout en procédés, organisationnelles et en marketing ont des effets significatifs positifs sur la productivité des entreprises françaises. De plus, les innovations en produit et en procédé favorisent mieux la productivité si elles sont accompagnées par des innovations organisationnelles et en marketing et vice versa. En troisième lieu, nous avons souligné une forte persistance des inputs et des outputs d’innovation qui appelle des mesures d’incitation spécifiques aux entreprises non innovantes. Nos résultats suggèrent aussi que pour accélérer la mise en place de leurs innovations, les entreprises sont appelées à intérioriser leurs activités de R&D plutôt que de les externaliser. Enfin, il est avéré que les projets innovants nécessitent du temps pour générer des gains de productivité. Ce décalage de rendement doit être pris en compte lors de l’instauration des plans de financement. / This thesis analyzes the determinants and the implications of innovation while highlighting the complementarity between technological and organizational competencies and their accumulation in time. Our econometric study is based on the data of three waves of French CIS (1998-2006). Firstly, our results suggest that the innovation is determined by the company’s internal and external characteristics. Moreover, the complementarity tests showed that in order to profit fully from the positive effect of the partnership and the R & D efforts on innovation, those must be accompanied by an organizational architecture supporting the knowledge creation and distribution. Secondly, our results show that especially process, organizational and marketing innovations have positive significant effects on the French companies’ productivity. Besides, product and process innovations promote more productivity if they are accompanied by organizational and marketing innovations and vice versa. Thirdly, we underlined a strong persistence of the innovation’s inputs and outputs which calls specific incentives to the no innovating companies. Our results suggest also that to accelerate the installation of their innovations, the firms are invited to interiorize their R & D activities rather than to outsource them. Finally, we proved that the innovating projects require time to generate productivity gains. This shift of output must be taken into account while preparing the financing plans.

This study investigated the academic self-efficacy and persistence goals of 72 diverse female Engineering majors. Social Cognitive Career Theory (Lent, Brown, & Hackett, 1994) coupled with Practice Theory (Bourdieu, 1998) and Social Capital Theory (Lin, 1999) served as the theoretical framework. The relationships between social cognitive variables (engineering self-efficacy, outcome expectations, interests) as well as the influence of contextual and cultural variables (perceived campus climate, distance from privilege, and access to resources) on female students' intent to persist in Engineering were examined. Hierarchical linear regression revealed that only outcome expectations significantly contributed to the prediction of female students' intent to persist in Engineering. Exploratory analysis revealed that outcome expectations were most influential in predicting Engineering self-efficacy. Including privilege and perception of campus climate into the model significantly predicted self-efficacy above and beyond the original SCCT variables. This study supports the addition of cultural contextual variables in the SCCT choice model and warrants future research with minority female populations. Key words: women in STEM, social cognitive career theory, privilege, persistence, underrepresented students

Chlamydia trachomatis is a Gram-negative, obligate intracellular pathogen that is the causative agent of sexually transmitted infections and the ocular disease trachoma. Chlamydia trachomatis undergoes a biphasic developmental cycle differentiating between the infectious elementary body (EB) and the replicative reticulate body (RB). Under certain stress conditions, C. trachomatis can stall its developmental cycle and enter an aberrant state termed persistence. While in a persistent state, C. trachomatis is refractory toward antibiotics, can evade the host immune response, and becomes undetectable using standard clinical detection methods. Environmental and other pathogenic microbes are known to utilize partner switching mechanisms (PSM) to regulate sigma factors used to initiate a stress response. For this reason, this study focuses on the chlamydial PSM, its role in regulating the availability of the housekeeping sigma factor σ66, and its role in the developmental cycle and stress response of C. trachomatis. The chlamydial PSM is composed of five known proteins: the anti-sigma factor RsbW, two anti-anti-sigma factors RsbV1 and RsbV2, a regulatory phosphatase RsbU, and a second phosphatase-like protein CTL0852. In order to test the role of the PSM in the chlamydial stress response, a panel of C. trachomatis rsbV1 mutants were generated, persistence inducing iron starvation and tryptophan starvation cell culture conditions were optimized, and growth of the rsbV1 mutants under iron starvation conditions were assayed. No significant differences were seen between rsbV1 mutants under iron starvation nor recovery conditions as determined by progeny production and inclusion size analysis. Furthermore, this study generated PSM protein producing Escherichia coli strains for in vitro protein work and performed operon mapping of the PSM genes of C. trachomatis to help aid in future studies of the chlamydial PSM by facilitating the development of new chlamydial PSM mutants. This study gives phylogenetic support to the classification of ctl0852 as a chlamydial PSM gene by comparing relative mutations rates of PSM genes across chlamydial species.

This study explored whether the effects of student-faculty interaction on various outcomes - degree aspiration, college GPA, satisfaction with faculty contact, and satisfaction with the college experience - vary by student gender, ethnicity, social class, and first-generation status. The study used data on 95,537 students attending nine colleges who took the 2011 administration of the Student Experience in the Research University (SERU) survey. The findings revealed differences in the frequency of student-faculty interaction by social class and ethnicity, differences in the level of satisfaction with advising and access to faculty by social class, and positive relations between degree aspiration and specific interaction behaviors. The findings provide implications for educators, administrators, and others charged with maximizing the benefits of student-faculty interactions for all students to positively affect college persistence and retention.

Introdução: O aprendizado intencional/incidental pode influenciar a memória. A persistência deste efeito avaliado ao longo do tempo foi pouco estudada até o momento. Objetivos: Avaliar a persistência da memória comparando as aprendizagens intencional e incidental. Métodos: A amostra (120 sujeitos funcionalmente independentes, com idade variando de 18 a 81 anos), foi subdividida em dois grupos (experimental - condição ‘intenção de aprender’ - e controle). Uma abordagem ecológica foi utilizada para a avaliação do aprendizado incidental. As avaliações foram realizadas dois e sete dias após a codificação. Resultados: A intenção de aprender e a aquisição incidental (a partir de experiências de vida diária) melhoraram a recuperação da memória no dia dois, mas não sete dias após a codificação. Conclusão: Estes achados sugerem que o estado motivacional (espontâneo ou induzido) que modula o sistema da atenção deve ser importante para a melhora na recuperação das informações aprendidas. / Background: The intentional/incidental learning can influence memory. The persistence of this effect assessed over time has been little studied up to date. Objectives: To evaluate the persistence of memory comparing intentional and incidental learning conditions. Method: The sample (120 functionally independent subjects, age ranging from 18 to 81 years old), was subdivided into two groups (experimental - intention to learn condition - and control). An ecological approach was applied for the incidental learning condition. The assessments were performed two and seven days after the encoding. Results: The intention to learn and the incidental acquisition (from daily life experiences) improved performance two but not seven days after the encoding. Conclusions: These findings suggest that motivational state (spontaneous or induced) which module the system of attention may be important for the improvement in the retrieval of the information learned.