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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.
471

Demographic efficiency drivers in the Chinese energy production chain: A hybrid neural multi-activity network data envelopment analysis

Zhao, Y., Antunes, J.J.M., Tan, Yong, Wanke, P.F. 24 March 2023 (has links)
Yes / For meeting the external requirements of the Paris Agreement and reducing energy consumption per gross domestic product, China needs to improve its energy efficiency. Although the existing studies have attempted to investigate energy efficiency from different perspectives, little effort has yet been made to consider the collaboration among different stages in the production chain to produce energy outputs. In addition, various studies have also examined the determinants of energy efficiency, however, they mainly focused on technology and economic factors, no study has yet proposed and considered the influence of geographical factors on energy efficiency. In this article, we fill in the gap and make theoretical and empirical contributions to the literature. In this study, a two-stage analysis method is used to analyse energy efficiency and the influencing factors in China between 2009 and 2021. More specifically, from the theoretical/methodological perspective, a multi-activity network data envelopment analysis model is used to measure energy efficiency of different processes in the energy production chain. From the empirical perspective, we attempt to investigate the influence of geographical factors on energy efficiency through a neural network analysis. Meanwhile, the comparisons among different provinces are made. The result shows that the overall energy efficiency is low in China, and China relies more on the traditional energy industry than the clean energy industry. The efficiency level experiences a level of volatility over the examined period. Finally, we find that raw fuel pre-process and industry have a significant and positive impact on energy efficiency in China.
472

Demography and mating system shape the genome-wide impact of purifying selection in Arabis alpina

Laenen, B., Tedder, Andrew, Nowak, M.D., Toräng, P., Wunder, J., Wötsel, S., Steige, K.A., Kourmpetis, Y., Odong, T., Drouzas, A.D., Bink, M.C.A.M., Ågren, J., Coupland, G., Slotte, T. 13 September 2019 (has links)
Yes / Plant mating systems have profound effects on levels and structuring of genetic variation and can affect the impact of natural selection. Although theory predicts that intermediate outcrossing rates may allow plants to prevent accumulation of deleterious alleles, few studies have empirically tested this prediction using genomic data. Here, we study the effect of mating system on purifying selection by conducting population-genomic analyses on whole-genome resequencing data from 38 European individuals of the arctic-alpine crucifer Arabis alpina. We find that outcrossing and mixed-mating populations maintain genetic diversity at similar levels, whereas highly self-fertilizing Scandinavian A. alpina show a strong reduction in genetic diversity, most likely as a result of a postglacial colonization bottleneck. We further find evidence for accumulation of genetic load in highly self-fertilizing populations, whereas the genome-wide impact of purifying selection does not differ greatly between mixed-mating and outcrossing populations. Our results demonstrate that intermediate levels of outcrossing may allow efficient selection against harmful alleles, whereas demographic effects can be important for relaxed purifying selection in highly selfing populations. Thus, mating system and demography shape the impact of purifying selection on genomic variation in A. alpina. These results are important for an improved understanding of the evolutionary consequences of mating system variation and the maintenance of mixed-mating strategies. / This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1707492115/-/DCSupplemental.
473

Attaining Team Psychological Safety to Unlock the Potential of Diverse Teams

Chen, Victor H. 05 1900 (has links)
Team psychological safety fosters interpersonal risk-taking and constructive debate. Yet, how psychological safety develops in diverse teams needs to be explained. I apply collective regulatory lenses to shed light on how collective prevention focus (status quo) and collective promotion focus (growth) uniquely affect team psychological safety. I believe promotion focus makes it easier to attain psychological safety, while prevention focus makes it harder. Under a collective promotion lens, teams seek growth. Under a collective prevention lens, teams desire protection and not making things any worse. A pilot study of 76 students in 17 student project teams provided initial support for individual relationships in my model. In Study 2, an experiment, I manipulated team regulatory foci in three tasks (building towers, selling a house, negotiating a salary). I did not find significant mean group differences in psychological safety between promotion (n = 17) and prevention (n = 15) teams; yet, promotion teams experienced greater team viability in the final activity. In Study 3, I employed an experimental vignette method that suggested leadership conditions (e.g., leader humility vs transactional leadership) created differences in regulatory foci and subsequent differences in psychological safety with 343 working professionals in 7 scenarios.
474

The effects of technology, demographic and economic factors on voter error : an analysis of the 2002 and 2006 Florida gubernatorial elections

Khan, Javed 01 January 2008 (has links)
In a participatory democracy where every vote counts, voters expect that every vote will be counted. The voting machine is the instrument with which the voting public records its intent and appoints its representatives. In order for the democratic process to function, voting machines must properly function. This thesis examines voter error across Florida's 67 counties in the 2002 and 2006 gubernatorial elections in order to analyze and explain the pattern in voter error as represented by undervotes and overvotes across counties of various demographic and socio-economic characteristics, using different electronic voting systems in the 2002 and 2006 gubernatorial elections. The debate over the accuracy and accountability of touchscreen technology has been prominent for the last several election cycles and in the state of Florida resulted in the banning of use of these technologies. Yet, many counties in the United States still use touchscreen technology. Are touchscreen systems better equipped for reducing voter error? Correlation and Mean comparison analysis suggest that counties that primarily used touchscreen technology on Election Day had lower voter error rates than counties using optical scan technology in the 2006 election. Touchscreen technology was found to eliminate overvoting. Voter turnout was not found to have an effect on voter error rates. Voter error rates were found to be higher in the 2006 election than in the 2002 election for optical scan ballots but not for touchscreen systems. The question of enfranchisement is central to the democratic debate. If every vote counts, then should not every vote be accurately counted? Analysis has shown that the factors with the strongest and most consistent correlation with voter error rates for the 2004 and 2006 gubernatorial elections are educational level, median household income, county population size, and county population density for counties using optical scan systems. For counties using touchscreen machines the only significant correlation found was a moderately strong, negative relationship between median household income and voter error rate for the 2002 election. The correlation between the two was not significant for the 2006 election cycle.
475

The proprietary school sector: a demographic and financial aid profile

Yankosky, Richard E. January 1989 (has links)
The purpose of this study was to answer several questions concerning distribution of student financial aid in the proprietary school sector. The study was conducted in the Spring of 1989 using a Fall, 1986, nationally representative sample of 3,837 students attending less than two-year and two-year proprietary schools in the 50 states and the District of Columbia. The sample was drawn as part of the National Postsecondary Student Aid Survey (NPSAS) conducted by the National Center for Educational Statistics in the 1986/87 academic year. Data came from edited NPSAS tapes dated May 12, 1988. Several statistical procedures from the Statistical Analysis System (SAS) and Lotus 1-2-3 were used to answer research questions related to (1) types of educational services provided by proprietary schools, (2) types of students receiving financial aid; and, (3) types of aid packages distributed in these schools. Several of the major results are: (1) Proprietary schools provided short-term, high-cost vocational training leading to relatively low-paying entry-level jobs. (2) Over four-fifths (84%) of the students received financial aid. The majority of these students were unmarried (74%), female (67%), less than 23 years of age (52%), lived off-campus (98%) and attended school on a full—time basis (81%). Nearly one-half (48%) of dependent and 70 percent of independent recipients had incomes of less than $20,000. About 30 percent lacked a high school diploma. Almost 43% percent were from minority backgrounds with over 70 percent having incomes under $11,000. (3) Nearly 80 percent of the recipients received either a single source of aid or two sources of aid in their aid packages. About 88 percent of this aid came from the federal government with the Guaranteed Student Loan and Pell Grant programs the predominate sources. / Ed. D.
476

BME sex offenders in prison: the problem of participation in offending behaviour groupwork programmes: a tripartite model of understanding

Cowburn, I. Malcolm, Lavis, Victoria J., Walker, Tammi 16 April 2008 (has links)
Yes / This paper addresses the under representation of Black and minority ethnic (BME) sex offenders in the sex offender treatment programme (SOTP) of the prisons of England and Wales. The proportional over representation of BME men in the male sex offender population of the prisons of England and Wales has been noted for at least ten years. Similarly the under representation of BME sex offenders in prison treatment programmes has been a cause for concern during the last decade. This paper presents current demographic data relating to male BME sex offenders in the prisons of England and Wales. The paper draws together a wide range of social and cultural theories to develop a tripartite model for understanding the dynamics underlying the non-participation of BME
477

Parenting practices and mothers behavioural and demographic factors influencing their 2 year old child's physical activity

Horne, Maria, Bingham, Daniel, Nagy, Liana C., Clemes, S., Barber, Sally E. 06 1900 (has links)
Yes / To identify maternal factors that influence physical activity behaviour in 2 year old children.
478

Investigating The Association Of Demographic Factors On Methotrexate Delay-Clearance And Toxicity In Pediatric Oncology Patients: A Retrospective Chart Review

Alabdul Razzak, Belal 01 January 2024 (has links) (PDF)
High-dose methotrexate (HD MTX) is critical for treating pediatric malignancies such as acute lymphoblastic leukemia and neuro-carcinoma. However, its significant toxicity due to drug accumulation poses substantial risks. This retrospective study assesses the impact of demographic factors on MTX toxicity and clearance in pediatric oncology patients. Patient records from Saint Mary Hospital were analyzed, focusing on two MTX administration protocols: a 24-hour infusion followed by alkaline hydration and a 4-hour infusion followed by alkaline hydration. We hypothesize that factors such as age, body surface area (BSA), and body mass index (BMI) are associated with MTX clearance and toxicity. The study found no significant difference in clearance between genders, but females exhibited higher toxicity rates. Ethnicity comparisons showed Caucasians had the fastest clearance, followed by Hispanics, African Americans, and others, with Hispanics experiencing the highest toxicity rates. Patients with a BSA of less than one had a lower risk of delayed clearance, although toxicity levels were similar across BSA groups. BMI analysis indicated that patients with a BMI over 25 were at a higher risk of toxicity. Taken together, these findings suggest the need for personalized treatment plans in pediatric oncology to enhance therapeutic efficacy and reduce adverse effects. Future research should expand the sample size and develop a risk stratification guideline to identify patients suitable for outpatient treatment.
479

Determinants of contraceptive use among currently married women in Amhara and Oromiya Regions of Ethiopia

Zeleka, Teferi January 2009 (has links)
<p>The purpose of this research is to study the effect of different demographic and socio economic factors on the contraceptive use among currently married women of age 15-49 in the two regions of Ethiopia, Amhara (17,214,056) and Oromiya (27,158,471). Data are obtained from the 2005 Ethiopian Demographic and Health Survey (EDHS). Information on contraceptive use was provided by current use 1334 (14.7), future use 4017 (52.0), unmet need for spacing 1817 (20.0) and limiting 1249 (13.3) currently married women aged 15&ndash / 49 interviewed in the 2005 Ethiopian Demographic and Health Survey (EDHS).</p>
480

Demographic change and economic development at the local level in Brazil

Amaral, Ernesto F. L. (Ernesto Friedrich de Lima), 1977- 28 August 2008 (has links)
In this analysis, I estimate the impact of the changing relative size of the adult male population, classified by age and education groups, on the earnings of employed males living in 502 Brazilian local labor markets during four time periods between 1970 and 2000. The effects of shifts in the age distribution of the working age population have been studied in relation to the effect of the baby-boom generation on the earnings of different cohorts in the United States. However, the question has received little attention in the context of the countries in Asia and Latin America, which are now experiencing substantial shifts in their age-education distributions. Taking advantage of the huge variation across Brazilian local labor markets, the models in this research suggest that age-education groups are not perfect substitutes, so that own-cohort-education size depresses earnings, as expected by the theory. Compositional shifts are influential, attesting that this approach represents a fruitful way of studying this central problem in economic development, going beyond the effects normally analyzed by formal labor market equations. / text

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