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1	Multitasking and Distracted Learning: Motivation and Norms Barker, Bethany Brooke January 2017 (has links) No description available. Communication
2	Privacy Within Photo-Sharing and Gaming Applications: Motivation and Opportunity and the Decision to Download Hopkins, Ashley R. 20 September 2019 (has links) No description available. Journalism mobile applications apps smartphone social media privacy data datamining data mine Android Apple privacy permissions terms and conditions motivation opportunity decision-making gaming photo-sharing Facebook MODE model
3	"Expanded" local mode approach and isotopic effect in polyatomic molecules / Approche du mode local "étendu" et effet isotopique dans des molécules polyatomiques Fomchenko, Anna 18 September 2014 (has links) Dans cette thèse, sur la base de l'approche du mode local "étendu" et de la théorie générale de la substitution isotopique, nous obtenons un ensemble de relations analytiques simples entre les paramètres spectrocopiques (fréquences harmoniques, coefficients d'anharmonicité, paramètres rovibrationels, différents types de paramètres d'interaction de Fermi et de Coriolis) des molécules de CH2D2, CH3D et CHD3. Tous ces paramètres sont exprimés en termes de relations simples à partir des paramètres spectroscopiques de la molécule mère CH4. Des calculs tests avec des relations isotopiques montrent que même sans introduire d'informations majeures sur les espèces isotopiques, les résultats numériques de ces calculs sont en bon accord avec les données expérimentales et les calculs ab initio. A partir de le théorie des opérateurs de perturbation et des propriétés de symétrie des molécules axiales XYZ3 (C3v), nous déterminons des formules générales permettant la détermination des paramètres spectroscopiques sous la forme de fonctions des paramètres structuraux et des paramètres de la fonction potentiel intramoléculaire. Nous présentons aussi une approche permettant la détermination du hamiltonien de molécules polyatomiques qui permet de résoudre le problème de la description de la surface d'énergie potentielle via la construction et la diagonalisation d'une matrice hamiltonienne de grande dimension. / In this thesis, on the base of the "expanded", local mode approach and general isotopic substitution theory we obtain sets of simple analytical relations between spectroscopic parameters (harmonic frequencies, anharmonic coefficients, ro-vibrational parameters, different kinds of Fermi and Coriolis-type interaction parameters) of the CH2D2, CH3D and CHD3 molecules. All of them are expressed as simple functions of spectroscopic parameters of the mother CH4 molecule. Test calculations with the isotopic relations show that even without including prior informations about the isotopic species, numerical results of calculations are in a good agreement both with experimental data and results of ab initio calculations. On the base of operators perturbation theory and the symmetry properties of the axially symmetric XYZ3 (C3v) type molecules, we derive general formulae for the determination of the spectroscopic parameters in the form of functions of structural parameters and parameters of the intramolecular potential function. We present also an approach for determination of the Hamiltonian of polyatomic molecules that allows to solve the problem of potential energy surface determination via the construction and the diagonalization of a Hamiltonian matrix of large dimension. Spectroscopie moléculaire Molécule de méthane Espèces deutérées Le modèle mode local Relations isotopiques Fonction potentiel intramoléculaire Molecular spectroscopy Methane molecule Deuterated species Local mode model Isotopic relations Rotational and vibrational parameters Intramolecular potential function 530.1
4	Estudo dos espectros vibracionais de poliacetilenos substituídos / Study of vibrational spectra of substituted polyacetylenes Millen, Ricardo Prado 05 April 2005 (has links) Neste trabalho foram sintetizados a poli-2-etinilpiridina (P2EP), poli-4etinilpiridina (P4EP), o iodeto de poli(2-N-t-butilpiridiniumilacetileno) (P2EPtBu) e a poli-β-etinilnaftaleno (P&#946:EN), os quais são poliacetilenos substituídos. Estes polímeros, juntamente com o cloreto de poli(2-piridínio-2-piridilacetileno) (P2EPH), foram caracterizados por espectroscopia vibracional no infravermelho e Raman. Estes polímeros apresentaram variação na posição das bandas Raman com a energia da radiação excitante - chamada dispersão Raman ou fotosseletividade - da ordem de 10 cm-1, bem inferior ao apresentado pelo poliacetileno (cerca de 60 cm-1). Este deslocamento foi interpretado utilizando-se dois dos modelos existentes para descrever este fenômeno: o Modelo de Modo de Amplitude (AMM) e o Modelo de Coordenada de Conjugação Efetiva (ECCM), os quais fornecem informações sobre a estrutura polimérica e sobre seus níveis eletrônicos. Utilizando-se o AMM foi possível obter informações sobre os níveis eletrônicos excitados de mesma simetria que o estado eletrônico fundamental. Por outro lado, o ECCM, com a ajuda de cálculos DFT, mostrou diferenças na extensão da conjugação e no grau de dimerização entre o P2EP na forma cis e trans e indicou que este polímero apresentava, predominantemente, a estrutura cis, fato este confirmado pelos espectros no infravermelho. A dopagem com I2 provocou efeitos diferentes na estrutura dos polímeros. Os espectros no infravermelho dos polímeros dopados indicaram que o P2EP e o P2EPH apresentaram aumento na quantidade de segmentos cis enquanto o P2EPtBu apresentou diminuição na quantidade desses segmentos. Os espectros Raman dos polímeros dopados confirmaram os dados dos espectros no infravermelho. Esta diferença foi interpretada como sendo devida à diferença no volume do substituinte, pois grupos volumosos favorecem o isômero trans-cisóide onde a distância entre os substituintes é maior. A dopagem também levou a um aumento na condutividade dos polímeros, porém os valores de condutividade obtidos foram bem inferiores que os apresentados pelo poliacetileno dopado (10-5 a 10-7 contra 102 S cm-1, tipicamente). / In this work poly-2-ethynylpyridine (P2EP), poly-4-ethynylpyridine (P2EP), poly(2-N-t-butylpyridiniumylacetylene) iodide (P2EPtBu) and poly-β-pethynylnaphthalene (PβEN) were synthesized. These polymers, which are polyacetylenes derivatives, and poly(2-pyridinium-2-pyridylacetylene) chloride (P2EPH) were analyzed by vibrational techniques. It was observed that some Raman band positions shifted when excitation energy was changed, however this shift (ca. 10 cm-1) was substantially smaller than the presented by polyacetylene (ca. 60 cm-1). This phenomenon called Raman dispersion or photoselectivity - was examinated using Amplitude Mode Model (AMM) and Effective Conjugation Coordinate Model (ECCM) and gave us important information about polymer structure and its electronic energies levels. Using AMM it was possible to infere information about electronic excited states with the same symmetry of the electronic ground state. ECCM gave us evidences about differences in conjugation extension and dimerization degree between cis and trans structures. Besides this, ECCM was successful in indicating cis structure to P2EP. Infrared spectrum confirmed that this polymer is mainly cis. I2 doping of P2EP, P2EPH and P2EPtBu provoked differents perturbations in these systems. P2EP and P2EPH increased their cis segments amount, as showed by infrared spectra. On the other hand, this doping induced the decrease of cis segments in P2EPtBu. Raman spectroscopy supported these conclusions too. This difference was interpretated as due to the side group volume, which could favour one or another isomerization. Electronic conductivity increased by doping for all these three polymers, however the conductivity is considerably lower than the presented by polyacetylene (from 10-5 to 10-7 S cm-1 for these substituted polyacetylenes against typically 10-2 S cm-1 for polyacetylene). Amplitude mode model Conjugated polymers DFT DFT Dispersão Raman Dispersion raman Espectroscopia IR Espectroscopia molecular Estrutura molecular (Química teórica) Modelo de modo de amplitude Molecular spectroscopy Polímeros conjugados Spectroscopy IR
5	Estudo dos espectros vibracionais de poliacetilenos substituídos / Study of vibrational spectra of substituted polyacetylenes Ricardo Prado Millen 05 April 2005 (has links) Neste trabalho foram sintetizados a poli-2-etinilpiridina (P2EP), poli-4etinilpiridina (P4EP), o iodeto de poli(2-N-t-butilpiridiniumilacetileno) (P2EPtBu) e a poli-β-etinilnaftaleno (P&#946:EN), os quais são poliacetilenos substituídos. Estes polímeros, juntamente com o cloreto de poli(2-piridínio-2-piridilacetileno) (P2EPH), foram caracterizados por espectroscopia vibracional no infravermelho e Raman. Estes polímeros apresentaram variação na posição das bandas Raman com a energia da radiação excitante - chamada dispersão Raman ou fotosseletividade - da ordem de 10 cm-1, bem inferior ao apresentado pelo poliacetileno (cerca de 60 cm-1). Este deslocamento foi interpretado utilizando-se dois dos modelos existentes para descrever este fenômeno: o Modelo de Modo de Amplitude (AMM) e o Modelo de Coordenada de Conjugação Efetiva (ECCM), os quais fornecem informações sobre a estrutura polimérica e sobre seus níveis eletrônicos. Utilizando-se o AMM foi possível obter informações sobre os níveis eletrônicos excitados de mesma simetria que o estado eletrônico fundamental. Por outro lado, o ECCM, com a ajuda de cálculos DFT, mostrou diferenças na extensão da conjugação e no grau de dimerização entre o P2EP na forma cis e trans e indicou que este polímero apresentava, predominantemente, a estrutura cis, fato este confirmado pelos espectros no infravermelho. A dopagem com I2 provocou efeitos diferentes na estrutura dos polímeros. Os espectros no infravermelho dos polímeros dopados indicaram que o P2EP e o P2EPH apresentaram aumento na quantidade de segmentos cis enquanto o P2EPtBu apresentou diminuição na quantidade desses segmentos. Os espectros Raman dos polímeros dopados confirmaram os dados dos espectros no infravermelho. Esta diferença foi interpretada como sendo devida à diferença no volume do substituinte, pois grupos volumosos favorecem o isômero trans-cisóide onde a distância entre os substituintes é maior. A dopagem também levou a um aumento na condutividade dos polímeros, porém os valores de condutividade obtidos foram bem inferiores que os apresentados pelo poliacetileno dopado (10-5 a 10-7 contra 102 S cm-1, tipicamente). / In this work poly-2-ethynylpyridine (P2EP), poly-4-ethynylpyridine (P2EP), poly(2-N-t-butylpyridiniumylacetylene) iodide (P2EPtBu) and poly-β-pethynylnaphthalene (PβEN) were synthesized. These polymers, which are polyacetylenes derivatives, and poly(2-pyridinium-2-pyridylacetylene) chloride (P2EPH) were analyzed by vibrational techniques. It was observed that some Raman band positions shifted when excitation energy was changed, however this shift (ca. 10 cm-1) was substantially smaller than the presented by polyacetylene (ca. 60 cm-1). This phenomenon called Raman dispersion or photoselectivity - was examinated using Amplitude Mode Model (AMM) and Effective Conjugation Coordinate Model (ECCM) and gave us important information about polymer structure and its electronic energies levels. Using AMM it was possible to infere information about electronic excited states with the same symmetry of the electronic ground state. ECCM gave us evidences about differences in conjugation extension and dimerization degree between cis and trans structures. Besides this, ECCM was successful in indicating cis structure to P2EP. Infrared spectrum confirmed that this polymer is mainly cis. I2 doping of P2EP, P2EPH and P2EPtBu provoked differents perturbations in these systems. P2EP and P2EPH increased their cis segments amount, as showed by infrared spectra. On the other hand, this doping induced the decrease of cis segments in P2EPtBu. Raman spectroscopy supported these conclusions too. This difference was interpretated as due to the side group volume, which could favour one or another isomerization. Electronic conductivity increased by doping for all these three polymers, however the conductivity is considerably lower than the presented by polyacetylene (from 10-5 to 10-7 S cm-1 for these substituted polyacetylenes against typically 10-2 S cm-1 for polyacetylene). DFT Dispersão Raman Espectroscopia IR Espectroscopia molecular Estrutura molecular (Química teórica) Modelo de modo de amplitude Polímeros conjugados Amplitude mode model Conjugated polymers DFT Dispersion raman Molecular spectroscopy Spectroscopy IR
6	Evaluation of a Novel Biochemistry Course-Based Undergraduate Research Experience (CURE) Stefan M Irby (6326255) 15 May 2019 (has links) <p>Course-based Undergraduate Research Experiences (CUREs) have been described in a range of educational contexts. Although various learning objectives, termed anticipated learning outcomes (ALOs) in this project, have been proposed, processes for identifying them may not be rigorous or well-documented, which can lead to inappropriate assessment and speculation about what students actually learn from CUREs. Additionally, evaluation of CUREs has primarily relied on student and instructor perception data rather than more reliable measures of learning.This dissertation investigated a novel biochemistry laboratory curriculum for a Course-based Undergraduate Research Experience (CURE) known as the Biochemistry Authentic Scientific Inquiry Lab (BASIL). Students participating in this CURE use a combination of computational and biochemical wet-lab techniques to elucidate the function of proteins of known structure but unknown function. The goal of the project was to evaluate the efficacy of the BASIL CURE curriculum for developing students’ research abilities across implementations. Towards achieving this goal, we addressed the following four research questions (RQs): <b>RQ1</b>) How can ALOs be rigorously identified for the BASIL CURE; <b>RQ2</b>) How can the identified ALOs be used to develop a matrix that characterizes the BASIL CURE; <b>RQ3</b>) What are students’ perceptions of their knowledge, confidence and competence regarding their abilities to perform the top-rated ALOs for this CURE; <b>RQ4</b>) What are appropriate assessments for student achievement of the identified ALOs and what is the nature of student learning, and related difficulties, developed by students during the BASIL CURE? To address these RQs, this project focused on the development and use of qualitative and quantitative methods guided by constructivism and situated cognition theoretical frameworks. Data was collected using a range of instruments including, content analysis, Qualtrics surveys, open-ended questions and interviews, in order to identify ALOs and to determine student learning for the BASIL CURE. Analysis of the qualitative data was through inductive coding guided by the concept-reasoning-mode (CRM) model and the assessment triangle, while analysis of quantitative data was done by using standard statistical techniques (e.g. conducting a parried t-test and effect size). The results led to the development of a novel method for identifying ALOs, namely a process for identifying course-based undergraduate research abilities (PICURA; RQ1; Irby, Pelaez, & Anderson 2018b). Application of PICURA to the BASIL CURE resulted in the identification and rating by instructors of a wide range of ALOs, termed course-based undergraduate research abilities (CURAs), which were formulated into a matrix (RQs 2; Irby, Pelaez, & Anderson, 2018a,). The matrix was, in turn, used to characterize the BASIL CURE and to inform the design of student assessments aimed at evaluating student development of the identified CURAs (RQs 4; Irby, Pelaez, & Anderson, 2018a). Preliminary findings from implementation of the open-ended assessments in a small case study of students, revealed a range of student competencies for selected top-rated CURAs as well as evidence for student difficulties (RQ4). In this way we were able to confirm that students are developing some of the ALOs as actual learning outcomes which we term VLOs or verified learning outcomes. In addition, a participant perception indicator (PPI) survey was used to gauge students’ perceptions of their gains in knowledge, experience, and confidence during the BASIL CURE and, therefore, to inform which CURAs should be specifically targeted for assessment in specific BASIL implementations (RQ3;). These results indicate that, across implementations of the CURE, students perceived significant gains with large effect sizes in their knowledge, experience, and confidence for items on the PPI survey (RQ3;). In our view, the results of this dissertation will make important contributions to the CURE literature, as well as to the biochemistry education and assessment literature in general. More specifically, it will significantly improve understanding of the nature of student learning from CUREs and how to identify ALOs and design assessments that reveal what students actually learn from such CUREs - an area where there has been a dearth of available knowledge in the past. The outcomes of this dissertation could also help instructors and administrators identify and align assessments with the actual features of a CURE (or courses in general), use the identified CURAs to ensure the material fits departmental or university needs, and evaluate the benefits of students participating in these innovative curricula. Future research will focus on expanding the development and validation of assessments so that practitioners can better evaluate the efficacy of their CUREs for developing the research competencies of their undergraduate students and continue to render improvements to their curricula.</p> Biochemistry Education Course-based Undergraduate Research Course-based Research Experiences CURE anticipated learning outcomes ALOs ALO CURAs research abilities PICURA ALO matrix BASIL weighted-relevance WR verified learning outcomes VLOs CUREs biochemistry computational biochemistry bioinformatics biochemistry education chemistry education chemistry teaching laboratory upper-division ACE-Bio experimental competencies Authentic science inquiry chemical education assessment assessment design Student understanding student difficulties biochemistry laboratory experiments biochemistry teaching laboratory chemistry teaching laboratory chemistry teaching laboratories predicting protein function protein inquiry-based learning inquiry-based teaching content analysis open-ended survey interviews semi-structured interviews PPI participant perception indicator assessment triangle CRM conceptual reasoning mode conceptual-reasoning-mode model curriculum evaluation experimental abilities discovery skills learning objectives learning outcomes LO LOs collaborations collaborative course implementation implementation student difficuluties experimental learning experimental literacy data-representation ACE-Bio Network Likert-survey

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