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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.
21

The Evaluation of Methods to Rapidly Assess Beverage Intake and Hydration Status

Kostelnik, Samantha Bond 09 April 2020 (has links)
Dehydration can impact the general population but it is particularly detrimental for athletes, due to their physical performance requirements. Although fluids in general contribute to meeting hydration needs, some beverages aid in the rehydration process more than others. The Beverage Intake Questionnaire (BEVQ-15) is a food frequency questionnaire (FFQ) that can rapidly assess habitual beverage intake; this FFQ has been validated in children and adults. However, no beverage consumption questionnaire has been validated in athletes. In addition to monitoring fluid intake, hydration status can be assessed through urinary and blood indices. Urine color (UC) has been utilized as a practical hydration biomarker in several populations. However, this biomarker has not been validated among the general population of collegiate athletes. The first study (n=58): formulated a novel whey-permeate-based beverage to promote hydration and assess its sensory characteristics in the general population. The overall acceptability of the beverage was lower than the control beverage, according to a 9-point Likert scale (x̅ = 4.5 – 4.9 and x̅ = 6.7, respectively). The second study (n=120): evaluated the comparative validity and reliability of the BEVQ-15 and UC within NCAA Division 1 collegiate athletes. Associations were noted between the BEVQ-15 and multiple 24-hr dietary recalls (reference method) for total beverage fl oz and kcal (r=0.41 and r=0.47, p<0.05, respectively). There were associations between athlete's UC and urinary specific gravity (USG; hydration biomarker) rated by athletes and researchers (r=0.67 and 0.88, p<0.05, respectively). Lastly, a systematic review was performed to evaluate original research addressing the validity of UC as a hydration biomarker in the adult population more broadly, including athletes and older adults. Eleven of 424 articles met inclusion criteria, and the available research generally reported significant correlations between UC and other hydration indices (r=0.35-0.93). However, limitations in existing research were evident. Although the BEVQ-15 may be a valid beverage intake assessment method in collegiate athletes, additional modifications were identified which could improve its validity. Future work includes re-evaluating the validity and reliability of the BEVQ-15 specifically modified for athletes, as well as assessing the sensitivity of this FFQ to detect changes in beverage intake. / Doctor of Philosophy / Drinking adequate amounts of fluids is important for maintaining normal bodily functions. When body water losses exceed fluid intake, dehydration may result, which can lead to numerous consequences such as headaches, dizziness, decreased mental focus, and fatigue. An athlete, who has high physical demands, may experience these negative consequences as well as muscle cramps, increased strain on the heart, and decreased athletic performance. Some beverages can replenish lost fluids better than others, due to their electrolyte (i.e. sodium, potassium, magnesium) content. This may include whey-permeate based beverages. In order to prevent dehydration, it is important to monitor fluid consumption and fluid losses. A beverage intake questionnaire (BEVQ-15) can be used to quickly assess usual beverage intake. Studies have shown that this questionnaire is accurate in children, adolescents, and adults. However, there are currently no validated methods for usual habitual beverage intake in athletes. This dissertation evaluated the taste of a new whey-permeate hydration beverage, and the accuracy and test-retest reliability of the BEVQ-15 within NCAA Division 1 collegiate athletes and found positive results. Measurements in urine and blood can be also be used to assess hydration status, but some of these methods are more expensive and less practical for daily use in real-world settings. Urine color (UC) has been studied as a hydration indicator, but this dissertation is the first to evaluate the accuracy and reliability of this method within a diverse group of collegiate athletes, in a real-world setting. Our results suggest that UC is a simple and reasonably accurate hydration assessment method when compared to another urinary assessment method. Nonetheless, there is limited research which has studied this topic. Future work can address methods to improve the effectiveness of these approaches for maintaining and evaluating fluid intake and status in the collegiate athletic population.
22

Reframing the reproducibility crisis: using an error-statistical account to inform the interpretation of replication results in psychological research

Parker, Caitlin Grace 17 June 2015 (has links)
Experimental psychology is said to be having a reproducibility crisis, marked by a low rate of successful replication. Researchers attempting to respond to the problem lack a framework for consistently interpreting the results of statistical tests, as well as standards for judging the outcomes of replication studies. In this paper I introduce an error-statistical framework for addressing these issues. I demonstrate how the severity requirement (and the associated severity construal of test results) can be used to avoid fallacious inferences that are complicit in the perpetuation of unreliable results. Researchers, I argue, must probe for error beyond the statistical level if they want to support substantive hypotheses. I then suggest how severity reasoning can be used to address standing questions about the interpretation of replication results. / Master of Arts
23

Evaluation of the Repeatability and Reproducibility of Network-Level Pavement Macrotexture Measuring Devices

Keeney, Jacquelyn Nicole 21 August 2017 (has links)
The purpose of this thesis was to assess the repeatability and reproducibility of two high-speed macrotexture measuring systems. The first portion of the study collected macrotexture measurements using the two high-speed systems on the Virginia Smart Road facility and validated the reproducibility of the mean profile depth (MPD) measurements with reference CT Meter measurements. The various data sets were then compared with each other. The objective was to determine whether the two systems are collecting repeatable and reproducible data. The analysis showed that the two high-speed systems investigated have good repeatability (0.105 mm for the Ames and 0.113 mm for the SCRIM) when measuring the average MPD of the sections investigated. The two systems produce measurements that are highly-correlated (Ames R2 = 0.9591 and SCRIM R2 = 0.9157) with the reference ones obtained with the CT Meter. While the Ames systems, with the data processed using the Virginia Tech filter, measures MPD values that are very close to those of the CT Meter, with a virtually zero systematic bias. The SCRIM obtains slightly lower readings. The differences are thought to be due to the filtering of the raw pavement elevation measurements used by the SCRIM processing software to eliminate dropout and spikes in the laser measurements. / Master of Science / The researched compared two different devices used to record data for a surface property of pavement, macrotexture. The macrotexture is a measure of the spaces in between the particles making up the surface of the asphalt. This property is linked to the level of friction on the roadways affecting safety. The readings from each of the devices were validated through a reference device in order to insure they were obtaining reliable results on the Virginia Smart Road. The repeatability and reproducibility of each of the devices was examined to determine whether the two systems were collecting repeatable and reproducible data. It was determined the two devices had good repeatability and were highly correlated with the reference device. The first device called the Ames system obtained measurements very close to those of the reference device, with a virtually zero systematic bias. The second device called the SCRIM system obtained measurements close to the reference device but slightly lower. Through the comparisons and data analysis, an equation permitting users to convert readings from the SCRIM to Ames system and vice versa was computed. Because one device obtains slightly higher readings than the other, this equation is very important in order to have comparable results.
24

Improving reproducibility and standards in quantitative N-Glycoproteomic data

Hackett, William Edwin 30 September 2024 (has links)
More than half of all human proteins are glycosylated, making glycosylation one of the most abundant post-translational modifications in proteomics. N-Glycosylation is a prevalent and diverse type of glycosylation with key roles in regulating systems such as protein folding and host-pathogen recognition; without proper understanding of the heterogeneities of N-Glycosylation efforts to understand biological systems and efforts to combat the maladies that affect those systems will be hindered, knowingly and unknowingly. N-Glycosylation is a semi-stochastic process governed by local chemistries and enzymatic availability, and it is regulated by end process evaluation making modeling infeasible. This drives glycoproteomics to rely on observational data from tandem mass spectrometry; mass spectrometry is a powerful tool that comes with logistical and technical limitations on the availability and compatibility of data. N -Glycopeptides can be identified in tandem mass spectrometry data, but this is with greater uncertainty than traditional proteomics for a variety of factors. This uncertainty propagates into the quantification of these molecules, generating interdependent datasets with small sample sizes and high missing value rates. N-Glycans are inherently interrelated by the biosynthetic network that they’re processed in, and as a result they have a lot of shared information and chemical properties that make identification and quantification more difficult. While advances in N-Glycoproteomics continue there is still a lot needed for true and reliable understanding of quantitative N-Glycoproteomics. To make use of the existing data, an R-package called RAMZIS — Relative Assessment of m/z Identifications by Similarity — was developed. This toolkit focuses on data quality assessment and identifying broad differences between glycosylation sites. RAMZIS uses a series of permutation tests with a weighted Tanimoto similarity assessment, it provides researchers with information on their ability to use their data, the presence of outliers, the probable differentiability of glycosylation sites, and how to improve their future experimentations. Data Independent Acquisition (DIA) has enabled vast improvements in proteomic’s ability to quantify and identify proteins in complex samples, but these improvements cannot be directly applied to glycoproteomics. Glycoproteins are more heterogeneous than deglycosylated proteomic datasets and have lower overall signal, the latter compounding the issues made by the former. For glycoproteomics to make full use of the power of DIA and account for its idiosyncrasies, many bioinformatic advancements need to be made in glycopeptide identification, validation, and quantification. To this effort, we developed a python package called GlyLine as a framework to assess glycoproteomic DIA data; it tracks coeluting product ions of identified glycopeptides, splitting the signal from shared product ions to produce MS2 level quantifications of the identified glycopeptides and provide databases of information for further analysis. As glycoproteomics advances and comes into greater prominence, it is vital that experiments and bioinformatic workflows be repeatable, as quantitative glycoproteomic data are reported in many different ways that are often incompatible. We have worked with the MIRAGE Commission to develop a community based minimum reporting guideline for glycoproteomic experiments. / 2025-09-30T00:00:00Z
25

Rigor and Transparency i.e., How to prevent the zombie paper Apocalypse

Bandrowski, Anita 27 October 2016 (has links)
Presentation given on October 27, 2016 at Data Reproducibility: Integrity and Transparency program as part of Open Access Week 2016. / The NIH is now requiring the authentication of Key Biological Resources to be specified in a scored portion of most grant applications, but what does it mean to authenticate? We will discuss what Key Biological Resources are, the ongoing efforts to understand how to authenticate them and of course the resources available, including examples. The journal response to authentication will also be pointed to and practical steps that every researcher can take today to improve reporting of research in scientific publication.
26

Sharing Specifications or Repeatability in Computer Systems Research

Collberg, Christian S, Proebsting, Todd A. 27 October 2016 (has links)
Presentation given on October 27, 2016 at Data Reproducibility: Integrity and Transparency program as part of Open Access Week 2016. / We describe a study into the extent to which Computer Systems researchers share their code and data. Starting with 601 papers from ACM conferences and journals, we examine the papers whose results were backed by code to see for what fraction of these we would be able to obtain and build the code. Based on the results of this study, we propose a novel sharing specification scheme that requires researchers to specify the level of sharing that reviewers and readers can assume from a paper.
27

Methodological Rigour in Preclinical Research: Implications for its Scientific Validity and Biomedical Progress

Ramirez, Francisco Daniel 16 July 2019 (has links)
Preclinical research using animals often precedes and informs clinical trials; however, most attempts to translate findings from “bench-to-bedside” fail. There is growing concern that an important cause of failed translations is that much of preclinical research is not reproducible, with poor experimental methodology believed to be a major contributor. Four studies were conducted: (1) an assessment of reported study designs of preclinical experiments published in leading cardiovascular journals; (2) an examination of sex bias in preclinical cardiovascular research; (3) a comparison of experimental practices between male and female preclinical cardiovascular researchers; and (4) an analysis of the influence of journal initiatives on preclinical research quality. These studies suggest that (1) methodological shortcomings are prevalent and persistent in preclinical cardiovascular research; (2) women’s involvement in preclinical cardiovascular research is positively associated with considering sex as a biological variable; and (3) journals can exert considerable influence on the quality of published data.
28

"Processamento auditivo em teste e reteste: confiabilidade da avaliação" / Test and retest of auditory processing : reliability of the evaluation

Frascá, Maria Fernanda Simões dos Santos 01 September 2005 (has links)
A fim de avaliar a confiabilidade de alguns dos testes que avaliam o Processamento Auditivo (PA), foi realizado um estudo do tipo teste-reteste desta avaliação, em um intervalo de uma semana e um mês entre as duas situações. O desempenho de 40 indivíduos foi analisado em relação à situação de teste e reteste, normalidade versus alteração e orelha testada. Verificou-se que os testes do PA, utilizados neste estudo, demonstraram sua confiabilidade por meio do teste-reteste / In order to verify the reliability of some Auditory Processing (AP) tests was carried out a test-retest study in a break of a week and a month between the two situations. The performance of 40 individuals was analyzed regarding the situation (test-retest), normality versus alteration and tested ear. It was confirmed that the AP tests used in this study indicated their reliability through the test-retest
29

Análise da confiabilidade inter e intra-examinador na avaliação postural pela fotogrametria computadorizada / Intra and Inter Observers Reliability Analysis Through Photogrammetry.

Iunes, Denise Hollanda 11 January 2005 (has links)
O propósito deste trabalho foi verificar a reprodutibilidade bem como a repetibilidade do método de avaliação postural por meio da fotogrametria computadorizada. Para isto 21 indivíduos, com idade 24,2 ± 1,3 anos de idade, foram fotografados em posição anterior, posterior, perfil e face. Para realização destas fotografias foram demarcados sobre a pele pontos anatômicos que são normalmente utilizados na avaliação postural tradicional. A partir destes pontos foram analisados diferentes ângulos através do aplicativo ALCimagem-2000. Para a análise interexaminador as fotos foram avaliadas por três examinadores diferentes e os resultados comparados. Para a análise intraexaminador as mesmas fotos foram avaliadas pelo mesmo examinador em duas ocasiões diferentes com um mês de intervalo. Para a análise da repetibilidade do método os voluntários foram fotografados duas vezes com intervalo de uma semana e as fotos avaliadas pelo mesmo examinador. Para comparação dos resultados intra e interexaminadores foram aplicados o coeficiente de correlação intraclasse. Os resultados revelaram que o método proposto apresenta significativa confiabilidade interexaminadores. Dos ângulos estatisticamente confiáveis, alguns tiveram menor coeficiente de confiabilidade, principalmente os ângulos do plano sagital referentes às curvaturas vertebrais, como lordose cervical, cifose torácica e lordose lombar. Na avaliação intra-examinador só não apresentou confiabilidade o ângulo da cifose torácica. Na repetibilidade do método somente o ângulo inferior da escápula não apresentou confiabilidade. Portanto, a fotogrametria computadorizada sugere ser um método confiável para avaliação postural no plano frontal anterior e posterior. Porém, para a análise no plano sagital necessita de mais estudos para definir parâmetros de normalidade das curvaturas vertebrais. / The purpose of this work was to verify the reproducibility, as well as the method repeatibility for postural evaluation through photogrammetry. For that, 21 individuals being 24,2 ??1,3 years old were photographed in anterior, posterior, profile and face positions. To perform these photos, several anatomic sites, which are often used in the traditional postural evaluation, were marked on the skin. Different angles from these sites were examined through the program ALCimagem-2000. For the inter-examiner analysis, the photos were evaluated by three different examiners whose results were compared. For the intra-examiner analysis, the same photos were evaluated by the same examiner in two different occasions. For the analysis of the repeatibility of the method, the volunteers were photographed twice with a period of a week interval, and the photos were evaluated by the same examiner. For comparing inter and intraexaminer results, the intra-class correlation coefficient was applied. The results revealed that the proposed method presented good inter-examiner reliability. From the statistically reliable angles, some had a lesser reliability coefficient, mainly the sagital plane angles referring to vertebral flexures such as the cervical lordosis, thoracic kyphosis, and lumbar lordosis. In the intra-examiner evaluation, just the thoracic kyphosis angle hasn\'t presented reliability. As for the repeatibility of the method just the inferior scapular angle haven\'t presented reliability. Thus, computerized photogrammetry seem be a reliable method for postural evaluation on the frontal, anterior and posterior planes. However, the sagital plane needs more studies to define normality parameters for the vertebral flexures.
30

The effect of the duration and amplitude of spinal manipulation therapy on the spinal stiffness of a feline model

Vaillant, Michele 11 1900 (has links)
Introduction: The purpose of this study was to determine the effect of spinal manipulation therapy (SMT) duration and amplitude on spinal stiffness. Methods: Simulated SMTs were performed at the L6 spinous process in twenty-two felines. SMTs ranging from 25 to 250 ms duration were performed. Groups 1 and 2 received maximal displacements of 1.0mm to 3.0mm. Groups 3 and 4 received maximal loads of 25% to 85% body weight. Local stiffness was quantified by applying an indentation to the vertebra. Results: Repeated SMTs caused minimal changes in stiffness. The interaction effect of duration X displacement in Groups 1 and 2, and the effect of duration in Group 3 were significant. Conclusion: Repeated SMTs cause minimal changes in stiffness thought to be due to a viscoelastic response. Some of the changes following select SMT conditions may be the result of an interaction effect between SMT duration and amplitude. No specific threshold condition was identified as causing a greater stiffness change. / Physical Therapy

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