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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.
411

Obyvatelstvo na středočeském panství Škvorec od poloviny 18. do konce 19. století. Poznatky získané propojením tradičních a pokročilých metod historické demografie a metod historické sociologie. / The population in the Central Bohemian manor of Škvorec from the middle of the 18th to the end of the 19th century. Knowledge gained using traditional and advanced methods of historical demography and methods of historical sociology.

Janáková Kuprová, Barbora January 2021 (has links)
The population in the Central Bohemian manor of Škvorec from the middle of the 18th to the end of the 19th century. Abstract The aim of this study is to analyze the reproductive behavior (nuptiality, natality, female and male fertility, mortality) and the social structure of selected groups of the population of the Škvorec manor in the 18th and 19th century. The Škvorec manor which is located in the territory of today's Central Bohemia was an important agricultural area in given period. The complete nominal excerpts from parish registers were used to find numbers of all births, marriages and deaths. In addition to traditional historical- demography methods (especially the family reconstitution method and subsequent calculation of demographic indicators from family leaves), advanced statistical methods (survival analysis, Cox regression model) were also used for data analysis. These approaches are new in Czech historical demography and bring many advantages, which are presented in the work. The natural change of population development at the manor is compared with the Czech lands as a whole and in more detail with selected rural and urban localities. The results mostly correspond with the population development which was observed in the Czech lands. The number of inhabitants of the manor in the years...
412

Non-Steroidal Anti-Inflammatory Drug-Induced Cardiovascular Adverse Events: A Meta-Analysis

Gunter, B. R., Butler, K. A., Wallace, R. L., Smith, S. M., Harirforoosh, S. 01 February 2017 (has links)
What is known and objective: Although non-steroidal anti-inflammatory drugs (NSAIDs) have been studied in randomized, controlled trials and meta-analyses in an effort to determine their cardiovascular (CV) risks, no consensus has been reached. These studies continue to raise questions, including whether cyclooxygenase-2 (COX-2) selectivity plays a role in conferring CV risk. We performed a meta-analysis of current literature to determine whether COX-2 selectivity leads to an increased CV risk. Methods: We utilized randomized, controlled trials and prospective cohort studies. We selected eight NSAIDs based on popularity and COX selectivity and conducted a search of the MEDLINE, EMBASE, and Cochrane databases. Primary endpoints included any myocardial infarction (MI), any stroke, CV death, and a combination of all three (composite CV outcomes). Twenty-six studies were found that met inclusion and exclusion criteria. Comparisons were made between all included drugs, against placebo, and against non-selective NSAIDs (nsNSAIDs). Drugs were also compared against COX-2 selective inhibitors (COXIBs) with and without inclusion of rofecoxib. Results and discussion: Incidence of MI was increased by rofecoxib in all comparison categories [all NSAIDs (OR: 1·811, 95% CI: 1·379–2·378), placebo (OR: 1·655: 95% CI: 1·029–2·661), nsNSAIDs (OR: 2·155, 95% CI: 1·146–4·053), and COXIBs (OR: 1·800, 95% CI: 1·217–2·662)], but was decreased by celecoxib and naproxen in the COXIB comparison [(OR: 0·583, 95% CI: 0·396–0·857) and (OR: 0·609, 95% CI: 0·375–0·989, respectively]. Incidence of stroke was increased by rofecoxib in comparisons with all NSAIDs and other COXIBs [(OR: 1·488, 95% CI: 1·027–2·155) and (OR: 1·933, 95% CI: 1·052–3·549), respectively]. Incidence of stroke was decreased by celecoxib when compared with all NSAIDs, nsNSAIDs, and COXIBs [(OR: 0·603, 95% CI: 0·410–0·887), (OR: 0·517, 95% CI: 0·287–0·929), and (OR: 0·509, 95% CI: 0·280–0·925), respectively]. No NSAID reached statistical significance in regard to CV death. Incidence of the composite endpoint was increased by rofecoxib when compared against all NSAIDs, placebo, and other COXIBs [(OR: 1·612, 95% CI: 1·313–1·981), (OR: 1·572, 95% CI: 1·123–2·201) and (OR: 1·838, 95% CI: 1·323–2·554), respectively]. Incidence of composite endpoint was decreased by celecoxib in the all NSAIDs and COXIBs comparisons [(OR: 0·805, 95% CI: 0·658–0·986) and (OR: 0·557, 95% CI: 0.404–0.767), respectively]. When rofecoxib was removed from the COXIBs group, no difference was found with any comparison, suggesting rofecoxib skewed the data. What is new and conclusion: This instead of the meta-analysis suggests that COX-2 selectivity may not play a role in the CV risk of NSAIDs. Rofecoxib was the only drug to demonstrate harm and skewed the data of the COX-2 selective group.
413

Inférence statistique dans le modèle de mélange à risques proportionnels / Statistical inference in mixture of proportional hazards models

Ben elouefi, Rim 05 September 2017 (has links)
Dans ce travail, nous nous intéressons à l'inférence statistique dans deux modèles semi-paramétrique et non-paramétrique stratifiés de durées de vie censurées. Nous proposons tout d'abord une statistique de test d'ajustement pour le modèle de régression stratifié à risques proportionnels. Nous établissons sa distribution asymptotique sous l'hypothèse nulle d'un ajustement correct du modèle aux données. Nous étudions les propriétés numériques de ce test (niveau, puissance sous différentes alternatives) au moyen de simulations. Nous proposons ensuite une procédure permettant de stratifier le modèle à 1isques proportionnels suivant un seuil inconnu d'une variable de stratification. Cette procédure repose sur l'utilisation du test d'ajustement proposé précédemment. Une étude de simulation exhaustive est conduite pour évaluer les pe1fonnances de cette procédure. Dans une seconde partie de notre travail, nous nous intéressons à l'application du test du logrank stratifié dans un contexte de données manquantes (nous considérons la situation où les strates ne peuvent être observées chez tous les individus de l'échantillon). Nous construisons une version pondérée du logrank stratifié adaptée à ce problème. Nous en établissons la loi limite sous l'hypothèse nulle d'égalité des fonctions de risque dans les différents groupes. Les propriétés de cette nouvelle statistique de test sont évaluée au moyen de simulations. Le test est ensuite appliqué à un jeu de données médicales. / In this work, we are interested in the statistical inference in two semi-parametric and non-parametric stratified models for censored data. We first propose a goodnessof- fit test statistic for the stratified proportional hazards regression model. We establish its asymptotic distribution under the null hypothesis of a correct fit of the model. We investigate the numerical properties of this test (level, power under different alternatives) by means of simulations. Then, we propose a procedure allowing to stratify the proportional hazards model according to an unknown threshold in a stratification variable. This procedure is based on the goodness-of-fit test proposed earlier. An exhaustive simulation study is conducted to evaluate the performance of this procedure. In a second part of our work, we consider the stratified logrank test in a context of missing data (we consider the situation where strata can not be observed on all sample individuals). We construct a weighted version of the stratified logrank, adapted to this problem. We establish its asymptotic distribution under the null hypothesis of equality of the hazards functions in the different groups. The prope1ties of this new test statistic are assessed using simulatious. Finally, the test is applied to a medical dataset.
414

"Having Given Them Bayonets, We Will Not Withhold the Ballot"- Republicans and Black Suffrage in Reconstruction Ohio, 1865-1867

Mach, Jacob T. 30 April 2020 (has links)
No description available.
415

Regresní analýza dat o současném stavu / Regression analysis of current status data

Filipová, Anna January 2021 (has links)
Survival analysis often includes dealing with data that are censored. This thesis focuses on censoring in the form of current status data. We discuss seve- ral methods of regression analysis of current status data and focus mainly on a method that assumes that the time to event follows the additive hazards mo- del. Under the assumption of proportional hazards for the monitoring time, this method does not require knowing the baseline hazard function and allows us to use the theory and software which were developed for Cox model. We also pre- sent a modification of this method, a two-step estimator, and show that it is asymptotically normal and has the advantage of lower asymptotic variance.
416

NSAIDs-Induced Cardio- and Cerebro-Vascular Adverse Events: a Meta-analysis

Gunter, Bryan R., Butler, Kristen A., Wallace, Rick L., Smith, Steven M., Harirforoosh, Sam 01 February 2017 (has links)
What is known and objective: Although non-steroidal anti-inflammatory drugs (NSAIDs) have been studied in randomized, controlled trials and meta-analyses in an effort to determine their cardiovascular (CV) risks, no consensus has been reached. These studies continue to raise questions, including whether cyclooxygenase-2 (COX-2) selectivity plays a role in conferring CV risk. We performed a meta-analysis of current literature to determine whether COX-2 selectivity leads to an increased CV risk. Methods: We utilized randomized, controlled trials and prospective cohort studies. We selected eight NSAIDs based on popularity and COX selectivity and conducted a search of the MEDLINE, EMBASE, and Cochrane databases. Primary endpoints included any myocardial infarction (MI), any stroke, CV death, and a combination of all three (composite CV outcomes). Twenty-six studies were found that met inclusion and exclusion criteria. Comparisons were made between all included drugs, against placebo, and against non-selective NSAIDs (nsNSAIDs). Drugs were also compared against COX-2 selective inhibitors (COXIBs) with and without inclusion of rofecoxib. Results and discussion: Incidence of MI was increased by rofecoxib in all comparison categories [all NSAIDs (OR: 1·811, 95% CI: 1·379-2·378), placebo (OR: 1·655: 95% CI: 1·029-2·661), nsNSAIDs (OR: 2·155, 95% CI: 1·146-4·053), and COXIBs (OR: 1·800, 95% CI: 1·217-2·662)], but was decreased by celecoxib and naproxen in the COXIB comparison [(OR: 0·583, 95% CI: 0·396-0·857) and (OR: 0·609, 95% CI: 0·375-0·989, respectively]. Incidence of stroke was increased by rofecoxib in comparisons with all NSAIDs and other COXIBs [(OR: 1·488, 95% CI: 1·027-2·155) and (OR: 1·933, 95% CI: 1·052-3·549), respectively]. Incidence of stroke was decreased by celecoxib when compared with all NSAIDs, nsNSAIDs, and COXIBs [(OR: 0·603, 95% CI: 0·410-0·887), (OR: 0·517, 95% CI: 0·287-0·929), and (OR: 0·509, 95% CI: 0·280-0·925), respectively]. No NSAID reached statistical significance in regard to CV death. Incidence of the composite endpoint was increased by rofecoxib when compared against all NSAIDs, placebo, and other COXIBs [(OR: 1·612, 95% CI: 1·313-1·981), (OR: 1·572, 95% CI: 1·123-2·201) and (OR: 1·838, 95% CI: 1·323-2·554), respectively]. Incidence of composite endpoint was decreased by celecoxib in the all NSAIDs and COXIBs comparisons [(OR: 0·805, 95% CI: 0·658-0·986) and (OR: 0·557, 95% CI: 0.404-0.767), respectively]. When rofecoxib was removed from the COXIBs group, no difference was found with any comparison, suggesting rofecoxib skewed the data. What is new and conclusion: This instead of the meta-analysis suggests that COX-2 selectivity may not play a role in the CV risk of NSAIDs. Rofecoxib was the only drug to demonstrate harm and skewed the data of the COX-2 selective group.
417

EL Haiku en la poesía del Javier Sologuren y Alfonso Cisneros Cox

Belaúnde Degregori, Alonso 20 February 2018 (has links)
El presente trabajo analiza la aproximación al haiku de Javier Sologuren y Alfonso Cisneros Cox en el marco del creciente interés por este género a nivel latinoamericano. El análisis se centra en la comparación de los haikus con el modelo clásico japonés, tal como lo practicó Matsuo Bashō, siguiendo las teorías de los estudiosos Keene, Rodríguez Izquierdo, Rubio, Blyth y Haya Segovia. El haiku es valorado y ponderado como una expresión poética orientada a evocar un instante de experiencia en la naturaleza, logrando despertar el asombro ante la maravilla de la existencia. Los resultados del trabajo revelan la íntima afinidad de ambos poetas con el género, las modalidades de apropiación que practicaron, la priorización de ciertos aspectos estilísticos y espirituales en su comprensión del haiku, la innovación en los recursos para lograrlo y la singularidad de sus creaciones, basada en la mezcla auténtica del género con sus propias poéticas. La principal conclusión que puede desprenderse de este trabajo es que los autores asimilaron este género poético para dar forma y expresión a su particular sensibilidad e integrarlo a la tradición poética peruana.
418

Regression Analysis for Ordinal Outcomes in Matched Study Design: Applications to Alzheimer's Disease Studies

Austin, Elizabeth 09 July 2018 (has links) (PDF)
Alzheimer's Disease (AD) affects nearly 5.4 million Americans as of 2016 and is the most common form of dementia. The disease is characterized by the presence of neurofibrillary tangles and amyloid plaques [1]. The amount of plaques are measured by Braak stage, post-mortem. It is known that AD is positively associated with hypercholesterolemia [16]. As statins are the most widely used cholesterol-lowering drug, there may be associations between statin use and AD. We hypothesize that those who use statins, specifically lipophilic statins, are more likely to have a low Braak stage in post-mortem analysis. In order to address this hypothesis, we wished to fit a regression model for ordinal outcomes (e.g., high, moderate, or low Braak stage) using data collected from the National Alzheimer's Coordinating Center (NACC) autopsy cohort. As the outcomes were matched on the length of follow-up, a conditional likelihood-based method is often used to estimate the regression coefficients. However, it can be challenging to solve the conditional-likelihood based estimating equation numerically, especially when there are many matching strata. Given that the likelihood of a conditional logistic regression model is equivalent to the partial likelihood from a stratified Cox proportional hazard model, the existing R function for a Cox model, coxph( ), can be used for estimation of a conditional logistic regression model. We would like to investigate whether this strategy could be extended to a regression model for ordinal outcomes. More specifically, our aims are to (1) demonstrate the equivalence between the exact partial likelihood of a stratified discrete time Cox proportional hazards model and the likelihood of a conditional logistic regression model, (2) prove equivalence, or lack there-of, between the exact partial likelihood of a stratified discrete time Cox proportional hazards model and the conditional likelihood of models appropriate for multiple ordinal outcomes: an adjacent categories model, a continuation-ratio model, and a cumulative logit model, and (3) clarify how to set up stratified discrete time Cox proportional hazards model for multiple ordinal outcomes with matching using the existing coxph( ) R function and interpret the regression coefficient estimates that result. We verified this theoretical proof through simulation studies. We simulated data from the three models of interest: an adjacent categories model, a continuation-ratio model, and a cumulative logit model. We fit a Cox model using the existing coxph( ) R function to the simulated data produced by each model. We then compared the coefficient estimates obtained. Lastly, we fit a Cox model to the NACC dataset. We used Braak stage as the outcome variables, having three ordinal categories. We included predictors for age at death, sex, genotype, education, comorbidities, number of days having taken lipophilic statins, number of days having taken hydrophilic statins, and time to death. We matched cases to controls on the length of follow up. We have discussed all findings and their implications in detail.
419

PREDICTIVE ANALYTICS FOR HOLISTIC LIFECYCLE MODELING OF CONCRETE BRIDGE DECKS WITH CONSTRUCTION DEFECTS

Nichole Marie Criner (14196458) 01 December 2022 (has links)
<p>  </p> <p>During the construction of a bridge, more specifically a concrete bridge deck, there are sometimes defects in materials or workmanship, resulting in what is called a construction defect. These defects can have a large impact on the lifecycle performance of the bridge deck, potentially leading to more preventative and reactive maintenance actions over time and thus a larger monetary investment by the bridge owner. Bridge asset managers utilize prediction software to inform their annual budgetary needs, however this prediction software traditionally relies only on historical condition rating data for its predictions. When attempting to understand how deterioration of a bridge deck changes with the influence of construction defects, utilizing the current prediction software is not appropriate as there is not enough historical data available to ensure accuracy of the prediction. There are numerical modeling approaches available that capture the internal physical and chemical deterioration processes, and these models can account for the change in deterioration when construction defects are present. There are also numerical models available that capture the effect of external factors that may be affecting the deterioration patterns of the bridge deck, in parallel to the internal processes. The goal of this study is to combine a mechanistic model capturing the internal physical and chemical processes associated with deterioration of a concrete bridge deck, with a model that is built strictly from historical condition rating data, in order to predict the changes in condition rating prediction of a bridge deck for a standard construction case versus a substandard construction case. Being able to measure the change in prediction of deterioration when construction defects are present then allows for quantifying the additional cost that would be required to maintain the defective bridge deck which is also presented. </p>
420

Dihydroisocoumarins, Naphthalenes, and Further Polyketides from Aloe vera and A. plicatilis: Isolation, Identification and Their 5-LOX/COX-1 Inhibiting Potency

Rauwald, Hans Wilhelm, Maucher, Ralf, Dannhardt, Gerd, Kuchta, Kenny 05 May 2023 (has links)
The present study aims at the isolation and identification of diverse phenolic polyketides from Aloe vera (L.) Burm.f. and Aloe plicatilis (L.) Miller and includes their 5-LOX/COX-1 inhibiting potency. After initial Sephadex-LH20 gel filtration and combined silica gel 60- and RP18-CC, three dihydroisocoumarins (nonaketides), four 5-methyl-8-C-glucosylchromones (heptaketides) from A. vera, and two hexaketide-naphthalenes from A. plicatilis have been isolated by means of HSCCC. The structures of all polyketides were elucidated by ESI-MS and 2D 1H/13C-NMR (HMQC, HMBC) techniques. The analytical/preparative separation of 3R-feralolide, 3′-O-β-d-glucopyranosyl- and the new 6-O-β-d-glucopyranosyl-3R-feralolide into their respective positional isomers are described here for the first time, including the assignment of the 3R-configuration in all feralolides by comparative CD spectroscopy. The chromones 7-O-methyl-aloesin and 7-O-methyl-aloeresin A were isolated for the first time from A. vera, together with the previously described aloesin (syn. aloeresin B) and aloeresin D. Furthermore, the new 5,6,7,8-tetrahydro-1-O-β-d-glucopyranosyl- 3,6R-dihydroxy-8R-methylnaphtalene was isolated from A. plicatilis, together with the known plicataloside. Subsequently, biological-pharmacological screening was performed to identify Aloe polyketides with anti-inflammatory potential in vitro. In addition to the above constituents, the anthranoids (octaketides) aloe emodin, aloin, 6′-(E)-p-coumaroyl-aloin A and B, and 6′-(E)-p-coumaroyl-7-hydroxy-8-O-methyl-aloin A and B were tested. In the COX-1 examination, only feralolide (10 µM) inhibited the formation of MDA by 24%, whereas the other polyketides did not display any inhibition at all. In the 5-LOX-test, all aloin-type anthranoids (10 µM) inhibited the formation of LTB4 by about 25–41%. Aloesin also displayed 10% inhibition at 10 µM in this in vitro setup, while the other chromones and naphthalenes did not display any activity. The present study, therefore, demonstrates the importance of low molecular phenolic polyketides for the known overall anti-inflammatory activity of Aloe vera preparations.

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