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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.
171

Nativity Status and Dietary and Physical Activity Behavior among United States Adults: Findings from the Health Information National Trends Survey (HINTS 4 Cycle 3)

Alese, Joyce T. 15 May 2015 (has links)
Background: Non-communicable diseases and chronic conditions continue to emerge as public health crises in the United States (U.S.) and globally. Obesity, one of the most notable of such conditions, is associated with significant morbidity and mortality. Compared to non-immigrants, U.S. immigrants are known to have lower risks of obesity. However, there is paucity of literature on how U.S. immigrants compare to native-born adults regarding obesity-related behavior. Objective: We aim to describe demographic characteristics, weight distribution, and distributions of specific obesity-related behaviors among immigrant and native-born U.S. adults. Secondarily, we aim to estimate associations between nativity status and obesity-related behavior among U.S. adults. Methodology: We analyzed data from the Health Information National Trends Survey conducted between September and December 2013 (HINTS 4 Cycle 3). The independent variable was nativity status (immigrant vs. native-born). Outcomes of interest were indicators of dietary behavior (fruit, vegetable, and soda intake) and indicators of physical activity level (sitting time spent on television/computer games/web surfing, participation in physical exercise, and participation in muscle training exercise). Bivariate analyses and multivariable logistic regression models were utilized in describing demographics, weight distribution, and associations between variables of interest. Statistical significance was determined using p-values < 0.05 and 95% CI around adjusted odds ratios. Results: A total of 3185 individuals participated in the survey. The overall male to female ratio was 1:1.6. Approximately 17% of participants were immigrants and roughly 83% were native-born U.S. adults. The mean age was 51 years (SD +/- 15) for immigrants and 55 years (SD+/-16) for native-born respondents. Among immigrants, the racial distribution was 55.3% Hispanic, 18.9% Asian, 14.7% White, 9.9% Black and 1.3% other races. About 25% of immigrants were obese, compared to 34% of non-immigrants. Immigrants were more likely than native-born respondents to take some quantity of fruit daily (adjusted OR = 1.88; 95% CI: 1.07 - 3.32; p = 0.0290); and less likely than native-born respondents to consume soda every week (adjusted OR = 0.74; 95% CI: 0.55 - 0.98; p = 0.0383). Immigrants were less likely than non-immigrants to spend 6 hours or more a day on sedentary leisure activities (adjusted OR = 0.64; 95% CI: 0.42 - 0.97; p = 0.0350). Immigrants were also more likely than non-immigrants to engage in physical activity of at least moderate intensity, at least once a week (adjusted OR = 1.48; 95% CI: 1.07 - 2.05; p = 0.0192). Conclusion: Compared to non-immigrants, U.S. immigrants appear to have a tendency towards healthier lifestyles regarding diet and physical activity behavior. Strategies to sustain such tendencies among immigrants will promote health and reduce risks of obesity, cancer and other chronic diseases in the U.S. More robust studies are needed to shed more light on various socio-economic, cultural and demographic factors that influence proximal determinants of obesity.
172

Emerging Ed-tech and Accessibility

Vora, Disha 12 1900 (has links)
Recent developments in the field of education have led to a proliferation of educational technologies (or “ed-tech”), yet access to educational content for students with special needs remains a challenge. This research study aims to assess the current state of accessibility in emerging ed-tech and to identify barriers in enabling educational content to be born accessible. Detailed discussions with various ed-tech platforms revealed less of a need for technical tools, but a more prevailing need for knowledge and education around accessibility – what it means and how best to incorporate accessibility into their platforms. The more experienced teams advocate incorporating accessibility into product development right from the design phase, while the younger teams expressed challenges in navigating accessibility laws and the dire need for easy-to-follow guidelines and best practices. A detailed review of educators' content creation processes reveals multiple dependencies in the ecosystem of ed-tech where partnerships and compatibilities are crucial in enabling accessibility throughout the process. Likewise, an urgent need exists for increasing awareness of accessibility among instructors authoring educational content using emerging ed-tech.
173

Barriers for Foreign-Born Students in Elite Post-Secondary Education in the United States

Lam, Charmian 22 July 2013 (has links)
Foreign-born students complete college at a lower rate when compared to native-born students. It is essential to examine both the known and latent barriers that prevent foreign-born students from successfully completing the first four years of college. The purpose of this study is to assess the applicability of Bourdieuian notions of capital in explaining the discrepancy in educational attainment between foreign-born and native born students. The data is from the 1999 National Longitudinal Survey of Freshmen (n=3176), a survey designed to test various theoretical explanations for minority underachievement in higher education. Stepwise regressions were used to determine the individual impact of nativity, race, cultural capital, and economic capital to graduating within four years. In the unadjusted model, nativity was moderately associated with four-year graduation (β=0.760; p=0.053). However in the fully adjusted model, I found that race was more important than nativity status when predicting the odds of graduating, with African American students having a significantly lower odds of graduating in four years (β=0.576; p=0.000), than white students. Gender and economic capital were also significantly associated with 4-year graduation rates, with men less likely to graduate than women (β=0.733; p=0.000). And individuals in the highest income category (over $75,000/year) were more likely to graduate in four years than those in the making less than 19,999 per year (β=1.645; p=0.028). Parental disciplinary style was also a significant (p=0.000) correlate with four year graduation rates. Future studies should repeat these inquiries in a dataset that includes less selective institutions.
174

Bornova aproximace založená na paprskové metodě / Ray-based Born approximation

Šachl, Libor January 2011 (has links)
Title: Ray-based Born approximation Author: Libor Šachl Department: Department of Geophysics Supervisor: RNDr. Luděk Klimeš, DrSc. Supervisor's e-mail address: klimes@seis.karlov.mff.cuni.cz Abstract: One of the aims of this thesis was coding of program grdborn.for for computing the 2D and 3D ray-based Born approximation of the first order in an inhomoge- nous isotropic medium without attenuation. The computation of 3D amplitudes using the 2D Born approximation is based on the correction term, which is de- rived. The program is further used in computing the Born approximation in various models. We test its performance in three simple models. We study the effect of the discretization, the spurious waves introduced by the finite size of the grid etc. In the next step, we focus on the computations in more compli- cated models. We compute the Born seismograms in 2D heterogenous models. We study the diffracted waves, the effects of caustics etc. Keywords: Born approximation, ray theory, velocity model, perturbation 1
175

An explorative study on small-sized game development firms from a born global perspective

Do Amaral, Eduardo, Walther, Kevin January 2017 (has links)
The existing literature provides a variety of drivers enabling rapid internationalization of born global firms. This explorative study with its inductive approach attempts to analyze to what extent born global theory can be used to understand internationalization in the context of small-sized game development firms. Five interviews of a qualitative nature are used to collect data from founders of firms in this under-researched context. The data collection process is based on an operationalization of concepts based on the three categories of founder, organizational and macro-environmental drivers. The findings show that the firms can be aligned to three different stages of their business development, from subcontracting, to game development, to self-publishing. Subcontractors are not born global, but game developers must develop games with global market potential. These firms are pushed to be international by the heavily globalized nature of their industry and digital nature of both the products and the distribution platforms. Founder and organizational factors do not drive the born global approach as much as the environment, but still play a role in explaining the business of these firms. Overall, the findings of this thesis may provide a guiding point for further research in this specific context of firms acting in an industry with immediate internationalization.
176

Determining factors of location choice in the modern era : A cross-case analysis on tech companies

Sjöstrand, Ludwig, Raske, Robin, Klevbo, Carl January 2019 (has links)
The emergence of digitalization and globalization has given birth to firms who cater to a global customer base and source resources from around the world at the click of a button. Nevertheless, as companies continue to innovate how they communicate, govern and internationalize, much of the research is built on a world before the emergence of the digitalized and globalized society we live in today. Finding a lucrative market is a crucial source of competitive advantage but if modern opportunities and challenges are disregarded, it could lead to grave economic downfalls. This paper investigates what factors modern technology firms take into account when evaluating potential location choice. This question further investigates how the nature of technology companies influence location choice. A qualitative study was conducted, five semi-structured interviews with five companies were conducted with each interview lasting on average 47 minutes.Three general findings were deducted from these interviews. Firstly, internal factors to the firm are still very much relevant to tech companies. Determinants such as top managements' experiential learning and networks, industry characteristics and the nature of the customer relationship. The second finding was that country-specific determinants were of less importance. There was no evidence showing that determinants such as natural resources were a factor. It was also shown that psychic and geographic distances were of less importance while human capital are of higher importance. Lastly factors which have lowered the barriers to enter a foreign location were found. These include the emergence of the gig economy and better communication technologies allowing for companies to govern distant offices from a centralized headquarter. These findings have been compiled by the authors into a new model of location choice factors for technology companies
177

A process of internationalization by digital born globals : ‘Case study on fintech companies’

Mesaros, Noémi, Turunen Forsbäck, Adriana January 2019 (has links)
Digital services have immeasurably transformed the world economy, and so people’s lives, over the past two decades. One industry where digitalization has been slower is the financial services. Nevertheless, this has changed in the past years with the emergence of fintech companies disrupting the traditional banks and payment solutions. Several studies have researched the internationalization process of digital born globals across different industries. However, due to how recent and emerging the fintech industry is, the area is understudied. To gain insight on the internationalization process of digital born globals within the fintech industry this study was based on an empirical multiple-case study including 4 fintech companies from Sweden and Finland. The main finding of this study is that fintech firms do not expand like other digital born globals but instead follow a more traditional, incremental internationalization process. We also observed that fintech companies used an online entry strategy initially allowing a fast entry process. In some cases, they also established offline presence. Overall, we hope to contribute to theory by giving insight on which factors that cause fintech companies to expand, how the internationalization process looks, how external partnerships might influence, and which challenges they might face.
178

K-Shell Ionization Cross Sections For Elements Se To Pd: 0.4 To 2.0 MeV

Criswell, Tommy L. 12 1900 (has links)
K-Shell ionization cross section for protons over the energy range of 0.4 to 2.0 MeV have been measured on thin targets of the elements Se, Br, Rb, Sr, Y, Mo and Pd. Total x-ray and ionization cross sections for the K-shell are reported. The experimental values of the ionization cross sections are compared to the non-relativistic plane-wave Born approximation, the binary-encounter approximation, the constrained binary-encounter approximation, and the plane-wave Born approximation with corrections for Coulomb-deflection and binding energy effects.
179

Health acculturation and type 2 diabetes management among Vietnamese, Chinese, Korean, and Latino adult immigrants in the US

Nguyen, Thuc-Nhi January 2015 (has links)
Thesis advisor: Thanh V. Tran / Diabetes management is a major part of treatment but many ethnic/racial minorities with type 2 diabetes do not make the needed adjustment. A key component of healthcare access is health acculturation, defined as a level of success in navigating the mainstream healthcare system. The overall goal of this study is to develop a measure of health acculturation and examine its relationship with diabetes management across several ethnic minority groups in the US. The first purpose is to investigate the relationship between health acculturation and type 2 diabetes management behaviors in a sample of foreign-born Vietnamese, Chinese, Korean and Latino adults. The second purpose is to assess ethnic differences by testing the interaction between health acculturation and ethnicity on diabetes management behaviors. Merged dataset from CHIS 2009 and 2011-2 were used for analysis. Multiple and logistic regression analysis revealed that those with high health acculturation skills performed more diabetes management than their counterparts. Latinos performed better than all Asian subgroups on most diabetes management behaviors regardless of the level of health acculturation. The study has implications for social workers and healthcare providers working with ethnic and minority populations. The results suggest that the health acculturation measure would be a good screening tool to identify immigrant populations who will most benefit from health intervention within the culture of western medicine. In addition, the results help to identify specific skills and tools needed by social workers and healthcare providers to better serve these populations. / Thesis (PhD) — Boston College, 2015. / Submitted to: Boston College. Graduate School of Social Work. / Discipline: Social Work.
180

Investigação da reconstrução tomográfica utilizando transdutores distribuídos de ultrassom. / Reconstruction tomography investigation using ultrasound distributed transducers.

Cardona Cardenas, Diego Armando 17 January 2018 (has links)
A Ultrassonografia é uma ferramenta que vem sendo bastante utilizada pelas equipes médicas para diagnosticar e monitorar diferentes doenças. Isto pode ser explicado pelo fato de ser não invasiva e ser livre de radiação ionizante. A tomografia por ultrassom (USCT), uma das classes de ultrassonografia, é apresentada como uma alternativa promissora, de baixo custo, na avaliação de patologias e tumores nas glândulas mamárias. Apesar disso, a eficiência dos algoritmos desenvolvidos para o USCT depende tanto dos seus parâmetros iniciais como das características dos objetos dentro do meio de propagação (refletividade, tamanho, contraste). Para melhorar os resultados dos algoritmos de USCT é comum inicializar estes algoritmos com informação anatômica da região a ser reconstruída (Priors). Apesar das melhoras, para baixos contrastes, os efeitos das alterações nos Priors sobre estes algoritmos não são claros, e além disso, não existem estudos sobre a geração e uso de Priors para altos contrastes. Neste trabalho foi investigada a reconstrução tomográfica quantitativa por ultrassom, desde informações provenientes da reflexão, transmissão e espalhamento das ondas de ultrassom, com o intuito de diminuir o erro nos algoritmos de USCT e gerar melhores Priors para múltiplos contrastes. Para este propósito, através de simulações, foram estudadas técnicas que usam a reflexão como caminho para conhecer regiões (máscara por reflexão) ou para inferir bordas dos objetos dentro do meio (Abertura Sintética de Transmissão (STA)), técnicas que assumem transmissão linear do som oferecendo uma ideia da velocidade dentro do meio (Técnicas de Reconstrução Algébrica (ART)) e algoritmos que usam a difração do som (Distorted Born Iterative Method (DBIM)) para, segundo certos limites, inferir melhor tanto bordas como velocidade dos objetos dentro do meio. Também foi analisada como esta última técnica se comporta diante de diversas inicializações (Priors). Como resultados e conclusões neste trabalho mostrou-se: como o aumento do contraste no meio gera os piores resultados do DBIM; perante a boas inicializações do meio de propagação, o algoritmo, independentemente do contraste, tende a gerar boas reconstruções; o uso de estratégias que delimitem ou diminuam o número de variáveis a serem encontradas (máscara por reflexão) junto com o DBIM possibilita uma convergência mais rápida e melhora desempenho deste; inicializar os objetos dentro do meio de propagação (Priors) com áreas maiores do que as esperadas, oferece melhores resultados no DBIM do que trabalhar com áreas menores; informações qualitativas provenientes da reflexão (STA) são relevantes e aumentam a sua importância conforme aumenta o contraste estudado; através dos algoritmos ART, é possível uma delimitação inicial dos objetos dentro do meio para certos contrastes. Estas informações quantitativas podem ser melhoradas por meio da execução conjunta do ART com uma variação do Modified Median Filter aqui proposta. / Ultrasonography is a tool that has been used by medical professionals to diagnose and to monitor different kinds of diseases. This can be explained by its characteristics, such as being non-invasive and being free of ionizing radiation. Ultrasound Tomography (USCT) is one of the classes of ultrasonography, and is presented as a promising low cost alternative in the evaluation of pathologies and tumors in the breast. However, the efficiency of the USCT-algorithms depends both on its initial parameters and of the objects characteristics within the propagation medium (reflectivity, size, contrast). To improve the results of the USCT-algorithms it is common to initialize the algorithms with a-priori anatomical information of the region to be reconstructed (Priors). Despite of improving the results of the USCT-algorithms for low contrasts, the effects of the Priors in these algorithms are not clear, and in addition, there are no studies about the generation and the use of Priors for high contrasts. In this work, quantitative reconstruction for ultrasound was investigated based on information from the reflection, transmission and scattering of ultrasound waves, in order to reduce the error in the USCT-algorithms and to generate better Priors for multiple contrasts. For this purpose, it was studied, through simulations, techniques that use reflection to differentiate regions (reflection mask), or to deduce objects borders within the propagation medium (synthetic transmission aperture (STA)), as well as techniques that assume linear sound transmission to get an idea of the velocity inside the propagation medium (algebraic reconstruction technique (ART)) and algorithms that use sound diffraction (Distorted Born Iterative Method (DBIM)) to better infer both edges and velocity of objects within the propagation medium. It was also analyzed how the DBIM behaves due to multiple initializations (Priors). As results and conclusions, it was shown: how the increase of contrast in the propagation medium generates the worse results of the DBIM; in the presence of a good initialization of the propagation medium, the DBIM, regardless of the contrast, tends to generate good reconstructions; the use of strategies that delimit or reduce the number of unknown variables (reflection mask) along with the DBIM enables fast convergence and it improves the DBIM\'s performance; initializing the objects within the propagation medium with areas larger than expected provides better DBIM results than working with smaller areas; qualitative information derived from the reflection (STA) are relevant and increase their importance as the contrast increases; initial delimitation of objects within the propagation medium for certain contrasts is possible via transmission reconstruction. This quantitative information can be improved through the implementation of ART together with a variation of the Modified Median Filter here proposed.

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