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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Sub-optimální algoritmy pro řešení úloh o přesouvání kamenů / Sub-optimal algorithms for solving sliding puzzles

Michalík, Petr January 2011 (has links)
Title: Sub-optimal algorithms for solving sliding puzzles Author: Petr Michalík Department: Department of Theoretical Computer Science and Mathematical Logic Supervisor: RNDr. Pavel Surynek, Ph.D. Supervisor's e-mail address: Pavel.Surynek@mff.cuni.cz In the present work techniques for solving the so-called sliding tiles puzzles, which generate optimal or sub-optimal solution, are studied. This thesis focuses especially on a specific variant of the puzzle: the (n^2-1)-puzzle. This work shows and compares current methods for solving this type of problem. A choosen method is a subject to a close analysis of complexity and is also implemented so that theoretical and experimental results could be confronted. An alternative sub-optimal algorithm is proposed and its theoretical analysis is presented. This algorithm is implemented as well and is compared with the existing algorithm. Both the theoretical analysis and the test results show that better (shorter) solutions can often be obtained using this alternative algorithm.
2

Propriedades fotofísicas de substituintes aromáticos em derivados da N-metil-1,8-naftalimida: uma correlação entre dados teóricos e experimentais / Photophysical properties of aromatic substituents in N-metil-1,8-naftalimida derivatives: correlation between theoretical and experimental data

Magalhães, Janildo Lopes 23 June 2006 (has links)
Os compostos N-metil-1,8-naftalimida (NI), 4-fenóxi-N-metil-1,8-naftalimida (PNI) e 4-naftóxi-N-metil-1,8-naftalimida (NNI) foram sintetizados e caracterizados por técnicas usuais de caracterização de compostos orgânicos. As propriedades fotofísicas desses compostos foram estudadas tanto no estado estacionário quanto resolvidas no tempo. Com base nessas medidas, verificamos que os espectros de absorção e de emissão apresentam deslocamento batocrômico quando os grupos fenóxi e naftóxi são introduzidos na posição C-4. Quando estes compostos são comparados com NI, os espectros de absorção apresentam deslocamentos de 27 e 28 nm e os de emissão de 50,2 e 65,4 nm para o PNI e NNI, respectivamente. Os compostos possuem altos rendimentos quânticos (= 0,50-0,92) em solventes apolares e baixos em solventes polares apróticos e próticos (= 0,12-0,014), que pode ser uma conseqüência da estabilização do estado singlete (S1). A intensidade de emissão dos compostos em dioxano decresce com adição de água, e a supressão ocorre pela combinação estática e dinâmica em conseqüência de uma interação específica soluto-solvente. O caráter doador-retirador dos substituintes foi avaliado por voltametria cíclica, onde os substituintes fenóxi e naftóxi garantem um caráter eletrodoador aos compostos correspondentes (PNI e NNI), uma vez que apresentam, respectivamente, seus potenciais de redução mais negativos - 1,187 e -0,985 V em relação a -0,829 V do NI. Numa tentativa de compreender melhor o comportamento desses substituintes, implementamos cálculos de DFT (Teoria do Funcional de Densidade). Estes sugerem que as propriedades fotofísicas dos compostos podem estar intrinsecamente relacionadas com as suas geometrias podendo assim explicar o deslocamento mais pronunciado na emissão em virtude de um maior grau de conjugação entre o grupo aromático substituinte e a naftalimida. / The compounds N-methyl-1,8-naphthalimide (NI), 4-phenoxy-N-methyl-1,8- naphthalimide (PNI) and 4-naphthoxy-N-methyl-1,8-naphthalimide (NNI) were synthesized and characterized by usually technique for organics compounds. The steady state and time-resolved photophysical properties of the compounds were studied. Both absorption and fluorescence spectra are red-shifted when the electron donor phenoxy and naphthoxy group is introduced at C-4 position. When compared to NI, the spectral shift in acetonitrile for PNI and NNI is 27 and 28 nm for the absorption, and the fluorescence emission is 50,2 and 65,4 nm, respectively. The compounds PNI and NNI show high quantum yields in non-polar aprotic solvents (f = 0,50- 0,92), and low ones in polar non-protic and protic solvents (f = 0,12-0,014), which can be assigned to stabilization of the singlet state (S1). The emission intensity of the PNI and NNI decrease by addition of water to dioxane solution, and the fluorescence quenching occurs by combination of dynamic and static contribution ascribed to specific solute?solvent interaction. The substituent donor-acceptor character has been evaluated by means of cyclical voltammetry showing that PNI in the ground state has a the higher donor character than NNI, since the reduction potentials are -1,187 and - 0,985 V, respectively. As an attempt to comprehend the behavior of these substituents, Density Functional Theory (DFT) calculations were performed. These calculations suggest that the photophysical properties oh the compounds may be intrinsically related to their geometries, thus explaining the more pronounced shift on the emission spectra, as a consequence of a higher degree of conjugation between the substituent aromatic-group and naphthalimide moiety.
3

Propriedades fotofísicas de substituintes aromáticos em derivados da N-metil-1,8-naftalimida: uma correlação entre dados teóricos e experimentais / Photophysical properties of aromatic substituents in N-metil-1,8-naftalimida derivatives: correlation between theoretical and experimental data

Janildo Lopes Magalhães 23 June 2006 (has links)
Os compostos N-metil-1,8-naftalimida (NI), 4-fenóxi-N-metil-1,8-naftalimida (PNI) e 4-naftóxi-N-metil-1,8-naftalimida (NNI) foram sintetizados e caracterizados por técnicas usuais de caracterização de compostos orgânicos. As propriedades fotofísicas desses compostos foram estudadas tanto no estado estacionário quanto resolvidas no tempo. Com base nessas medidas, verificamos que os espectros de absorção e de emissão apresentam deslocamento batocrômico quando os grupos fenóxi e naftóxi são introduzidos na posição C-4. Quando estes compostos são comparados com NI, os espectros de absorção apresentam deslocamentos de 27 e 28 nm e os de emissão de 50,2 e 65,4 nm para o PNI e NNI, respectivamente. Os compostos possuem altos rendimentos quânticos (= 0,50-0,92) em solventes apolares e baixos em solventes polares apróticos e próticos (= 0,12-0,014), que pode ser uma conseqüência da estabilização do estado singlete (S1). A intensidade de emissão dos compostos em dioxano decresce com adição de água, e a supressão ocorre pela combinação estática e dinâmica em conseqüência de uma interação específica soluto-solvente. O caráter doador-retirador dos substituintes foi avaliado por voltametria cíclica, onde os substituintes fenóxi e naftóxi garantem um caráter eletrodoador aos compostos correspondentes (PNI e NNI), uma vez que apresentam, respectivamente, seus potenciais de redução mais negativos - 1,187 e -0,985 V em relação a -0,829 V do NI. Numa tentativa de compreender melhor o comportamento desses substituintes, implementamos cálculos de DFT (Teoria do Funcional de Densidade). Estes sugerem que as propriedades fotofísicas dos compostos podem estar intrinsecamente relacionadas com as suas geometrias podendo assim explicar o deslocamento mais pronunciado na emissão em virtude de um maior grau de conjugação entre o grupo aromático substituinte e a naftalimida. / The compounds N-methyl-1,8-naphthalimide (NI), 4-phenoxy-N-methyl-1,8- naphthalimide (PNI) and 4-naphthoxy-N-methyl-1,8-naphthalimide (NNI) were synthesized and characterized by usually technique for organics compounds. The steady state and time-resolved photophysical properties of the compounds were studied. Both absorption and fluorescence spectra are red-shifted when the electron donor phenoxy and naphthoxy group is introduced at C-4 position. When compared to NI, the spectral shift in acetonitrile for PNI and NNI is 27 and 28 nm for the absorption, and the fluorescence emission is 50,2 and 65,4 nm, respectively. The compounds PNI and NNI show high quantum yields in non-polar aprotic solvents (f = 0,50- 0,92), and low ones in polar non-protic and protic solvents (f = 0,12-0,014), which can be assigned to stabilization of the singlet state (S1). The emission intensity of the PNI and NNI decrease by addition of water to dioxane solution, and the fluorescence quenching occurs by combination of dynamic and static contribution ascribed to specific solute?solvent interaction. The substituent donor-acceptor character has been evaluated by means of cyclical voltammetry showing that PNI in the ground state has a the higher donor character than NNI, since the reduction potentials are -1,187 and - 0,985 V, respectively. As an attempt to comprehend the behavior of these substituents, Density Functional Theory (DFT) calculations were performed. These calculations suggest that the photophysical properties oh the compounds may be intrinsically related to their geometries, thus explaining the more pronounced shift on the emission spectra, as a consequence of a higher degree of conjugation between the substituent aromatic-group and naphthalimide moiety.
4

Does It Work for Me? Supporting Self-Experimentation of Simple Health Behavior Interventions

January 2019 (has links)
abstract: Many individual-level behavioral interventions improve health and well-being. However, most interventions exhibit considerable heterogeneity in response. Put differently, what might be effective on average might not be effective for specific individuals. From an individual’s perspective, many healthy behaviors exist that seem to have a positive impact. However, few existing tools support people in identifying interventions that work for them, personally. One approach to support such personalization is via self-experimentation using single-case designs. ‘Hack Your Health’ is a tool that guides individuals through an 18-day self-experiment to test if an intervention they choose (e.g., meditation, gratitude journaling) improves their own psychological well-being (e.g., stress, happiness), whether it fits in their routine, and whether they enjoy it. The purpose of this work was to conduct a formative evaluation of Hack Your Health to examine user burden, adherence, and to evaluate its usefulness in supporting decision-making about a health intervention. A mixed-methods approach was used, and two versions of the tool were tested via two waves of participants (Wave 1, N=20; Wave 2, N=8). Participants completed their self-experiments and provided feedback via follow-up surveys (n=26) and interviews (n=20). Findings indicated that the tool had high usability and low burden overall. Average survey completion rate was 91%, and compliance to protocol was 72%. Overall, participants found the experience useful to test if their chosen intervention helped them. However, there were discrepancies between participants’ intuition about intervention effect and results from analyses. Participants often relied on intuition/lived experience over results for decision-making. This suggested that the usefulness of Hack Your Health in its current form might be through the structure, accountability, and means for self-reflection it provided rather than the specific experimental design/results. Additionally, situations where performing interventions within a rigorous/restrictive experimental set-up may not be appropriate (e.g., when goal is to assess intervention enjoyment) were uncovered. Plausible design implications include: longer experimental and phase durations, accounting for non-compliance, missingness, and proximal/acute effects, and exploring strategies to complement quantitative data with participants’ lived experiences with interventions to effectively support decision-making. Future work should explore ways to balance scientific rigor with participants’ needs for such decision-making. / Dissertation/Thesis / Doctoral Dissertation Exercise and Nutritional Sciences 2019
5

Comparative investigation on clinical trial designs

Wang, Jing Unknown Date
No description available.
6

Synthesis of Nitrogen-Containing Compounds from Terminal Alkynes and Sulfonyl Azides via N-Sulfonyl-1,2,3-triazoles / N-スルホニル-l, 2, 3- トリアゾールを経由する末端アルキンとスルホニルアジドからの含窒素化合物の合成法

Funakoshi, Yuuta 25 September 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20713号 / 工博第4410号 / 新制||工||1685(附属図書館) / 京都大学大学院工学研究科合成・生物科学専攻 / (主査)教授 村上 正浩, 教授 杉野目 道紀, 教授 松原 誠二郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
7

Development of New Synthetic Transformations of N-Sulfony1-1,2,3-triazoles / N-スルホニル-1,2,3-トリアゾール類の新しい分子変換反応の開発

Zhao, Qiang 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21796号 / 工博第4613号 / 新制||工||1718(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 村上 正浩, 教授 松田 建児, 教授 中尾 佳亮 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
8

FYSISK AKTIVITET, SÖMN OCH KOGNITION: : En pilotstudie med fokus på dynamiska inomindividssamband

Ali, Dana, Grenholm, Victoria January 2023 (has links)
University students experience negative emotions due to their study situation, which adversely affects their academic performance. Previous between-group and between-individual studies have demonstrated that cognition, physical activity, and sleep serve as predictors of academic performance. The objective of this pilot study was to examine the potential relationship between physical activity, sleep, and cognition within days, as well as to explore whether physical activity and sleep have a bidirectional relationship within days. This observational study consisted of five N-of-1 studies involving university students aged 22-29. Physical activity levels were measured using accelerometers, while cognition was assessed using the memory span test within the m-Path app. Sleep quality and duration were self-assessed through the ecological momentary assessment approach within the m-Path app. The study did not yield statistically significant findings. It is important to note that the study's methodological choices may have hindered the detection of potentially significant associations and effects. Future studies should employ more objective measurement methods, increase the number of measurement occasions, and include a more diverse sample group in order to further investigate these relationships.
9

Desenvolvimento de sistema de análise por injeção seqüencial para determinação espectrofotométrica da capacidade antioxidante em bebidas empregando o radical derivado do N-fenil-1, 4-fenilenodiamino

França, Leandro de Moura 25 February 2011 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2014-09-05T15:25:03Z No. of bitstreams: 1 Dissertação LeandrodMF.pdf: 1496532 bytes, checksum: a3f1f8effe11a679e223ba5bdceeeb54 (MD5) / Approved for entry into archive by Fatima Cleômenis Botelho Maria (botelho@ufba.br) on 2014-09-05T15:56:02Z (GMT) No. of bitstreams: 1 Dissertação LeandrodMF.pdf: 1496532 bytes, checksum: a3f1f8effe11a679e223ba5bdceeeb54 (MD5) / Made available in DSpace on 2014-09-05T15:56:02Z (GMT). No. of bitstreams: 1 Dissertação LeandrodMF.pdf: 1496532 bytes, checksum: a3f1f8effe11a679e223ba5bdceeeb54 (MD5) / CNPq / Neste trabalho foi proposto um sistema de análises por injeção sequencial (SIA) para determinação espectrofotométrica da capacidade antioxidante em amostras de bebidas, a partir da geração “in situ” do radical derivado do reagente N-fenil-1,4-fenilenodiamino (NFFD•+). O radical NFFD•+ foi produzido em linha pela oxidação do NFFD empregando o Fe3+ como oxidante. Na otimização do sistema SIA foram avaliados os seguintes parâmetros: ordem de aspiração dos reagentes e amostra, estabilidade da solução de NFFD, pH da amostra, proporção NFFD/Fe3+, volumes das soluções dos reagentes e amostra e tempo de interrupção do fluxo. O ácido gálico foi empregado como padrão de calibração para os ensaios. Após as etapas de otimização univariada do método proposto obteve-se faixa linear de 10 a 40 mg L-1, com limites de detecção (3σ) de 1,0 mg L-1 e quantificação (10σ) de 3,3 mg L-1, respectivamente. Para avaliar o método proposto, foram realizados testes de reatividade do radical NFFD•+ frente a compostos fenólicos, tiólicos e de outra natureza. A redução do sinal analítico frente a inibição do radical derivado do NFFD foi mais pronunciada para ácido ascórbico, ácido tânico e cisteína, nesta ordem. A capacidade antioxidante com o radical derivado do NFFD foi avaliada em amostras de vinhos e chás, e os resultados foram concordantes com os métodos de referência (Folin-Denis, ABTS e DPPH), de acordo com o coeficiente de correlação, além do ensaio com radical DMPD•+, baseado no teste t. Assim a amina NFFD por ser utilizada para avaliação da atividade antioxidante em amostras de bebidas. Adicionalmente, as amostras de vinhos foram submetidas a testes de estabilidade temporal e avaliação do efeito do processo de ozonização em relação à variação da capacidade antioxidante / In this work was proposed a sequential injection system for spectrophotometric determination of antioxidant capacity in beverage samples with “in situ” radical generation from N-phenyl-1,4-phenylenediamine (NFFD•+). The radical NFFD•+ was produced by on line oxidation of NFFD employing Fe3+ as oxidant. The optimization of SIA system evaluated: aspiration order of reagents and sample, stability of the NFFD solution, sample pH, NFFD/Fe3+ proportion, reagents and sample volumes and stopped flow time. The gallic acid was used as standard of antioxidant compound for proposed sequential injection method. After chemical and physical univarieted optimization the linear range obtained in gallic acid concentration was from 10 to 40 mg L-1, with detection (3σ) and quantification (10σ) limits of 1.0 and 3.3 mg L-1, respectively. To evaluate selective of radical, studies of reactivity were performed with NFFD•+ and phenolic and thiol molecules and others compounds. The reducing capacity of NFFD•+ radical was observed preferentially for ascorbic acid, tannic acid and cysteine in this order. The antioxidant capacity with NFFD•+ radical was measured in samples of wines, infusions and teas. The results were agreement with the references methods (Folin-Denis, ABTS and DPPH), in accord with correlation coefficient, and additionally with the radical DMPD•+, based on t test. This way, the SIA spectrophotometric method exploring the radical NFFD•+ can be employed for the antioxidant capacity measured. Additionally, temporal stability and the ozonization effect in wine samples were evaluated using antioxidant capacity as parameter .
10

N-of-1-pathways MixEnrich: advancing precision medicine via single-subject analysis in discovering dynamic changes of transcriptomes

Li, Qike, Schissler, A. Grant, Gardeux, Vincent, Achour, Ikbel, Kenost, Colleen, Berghout, Joanne, Li, Haiquan, Zhang, Hao Helen, Lussier, Yves A. 24 May 2017 (has links)
Background: Transcriptome analytic tools are commonly used across patient cohorts to develop drugs and predict clinical outcomes. However, as precision medicine pursues more accurate and individualized treatment decisions, these methods are not designed to address single-patient transcriptome analyses. We previously developed and validated the N-of-1-pathways framework using two methods, Wilcoxon and Mahalanobis Distance (MD), for personal transcriptome analysis derived from a pair of samples of a single patient. Although, both methods uncover concordantly dysregulated pathways, they are not designed to detect dysregulated pathways with up- and down-regulated genes (bidirectional dysregulation) that are ubiquitous in biological systems. Results: We developed N-of-1-pathways MixEnrich, a mixture model followed by a gene set enrichment test, to uncover bidirectional and concordantly dysregulated pathways one patient at a time. We assess its accuracy in a comprehensive simulation study and in a RNA-Seq data analysis of head and neck squamous cell carcinomas (HNSCCs). In presence of bidirectionally dysregulated genes in the pathway or in presence of high background noise, MixEnrich substantially outperforms previous single-subject transcriptome analysis methods, both in the simulation study and the HNSCCs data analysis (ROC Curves; higher true positive rates; lower false positive rates). Bidirectional and concordant dysregulated pathways uncovered by MixEnrich in each patient largely overlapped with the quasi-gold standard compared to other single-subject and cohort-based transcriptome analyses. Conclusion: The greater performance of MixEnrich presents an advantage over previous methods to meet the promise of providing accurate personal transcriptome analysis to support precision medicine at point of care.

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