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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.
41

Prenatal famine exposure and later-life risk of type 2 diabetes: examining the relationship in a national longitudinal study in China

Li, Chihua January 2022 (has links)
Background The Chinese famine of 1959–61 has been widely interpreted as an important driver of current and future epidemics of type 2 diabetes (T2D). We conducted a systematic review and meta-analysis of prenatal famine exposure and type 2 diabetes (T2D) in China to summarize study characteristics, examine impacts of control selections on study results, and identify whether study results can be related to any characteristics. Methods We searched PubMed, Embase, Wanfang Data, and CNKI databases for studies that examined the relationship between T2D and prenatal exposure to the Chinese famine up to January, 2021. From included studies, we abstracted information on the number of T2D cases and populations at risk among individuals born during the famine (famine births), born before the famine (pre-famine births), and born after the famine (post-famine births). We examined the quality of studies with the modified Newcastle–Ottawa scale. We compared T2D in famine births to different controls: post-famine births, pre-famine and post-famine births combined (age-balanced), and pre-famine births. Fixed-effects models and random-effects models were used to calculate summary estimates. Heterogeneity across studies was assessed, and subgroup analyses were performed using sex, age at the survey, T2D measurements, famine intensity, residence, and publication language as possible effect modifiers. Findings Of 5,363 studies identified, 18 studies met our inclusion criteria. All studies defined famine exposure based on participants' years and/or months of births. Sample sizes ranged between around 300 and over 80,000 across studies. When post-famine births were used as controls, we found an increased risk of T2D (OR 1.48, 95% CI 1.30–1.68) among famine births based on the random-effects model. Using age-balanced controls, we did not find any increased risk of T2D (1.09, 95% CI 0.98–1.22). When pre-famine births were used as controls, famine was associated with a reduction in risk (0.85, 95% CI 0.75–0.97). Large variations and inconsistencies were identified in study design, famine intensity assessment, and covariate adjustment across studies. Conclusion Our analysis shows that it still remains an open question whether the Chinese famine has contributed substantially to the current T2D epidemic in China. Studies with more rigorous methods will need to quantify this relationship. The four-level famine intensity instrument developed in this study is a robust measure to identify a potential dose-response relation between famine exposure and health outcomes. It is likely to improve the reproducibility and generalizability of future studies.
42

Essays in Economics of Social Security Disability Insurance and Health

Kim, Seonghoon 09 August 2013 (has links)
No description available.
43

Childhood diet: a closer examination of the evidence from dental tissues using stable isotope analysis of incremental human dentine

Beaumont, Julia, Gledhill, Andrew R., Lee-Thorp, Julia A., Montgomery, Janet 29 August 2013 (has links)
No / Incremental dentine analysis utilizes tissue that does not remodel and that permits comparison, at the same age, of those who survived infancy with those who did not at high temporal resolution. Here, we present a pilot study of teeth from a 19th-century cemetery in London, comparing the merits of two methods of obtaining dentine increments for subsequent isotope determination. Covariation in ¿13C and ¿15N values suggests that even small variations have a physiological basis. We show that high-resolution intra-dentine isotope profiles can pinpoint short-duration events such as dietary change or nutritional deprivation in the juvenile years of life.
44

The Great Irish Famine: identifying starvation in the tissues of victims using stable isotope analysis of bone and incremental dentine collagen

Beaumont, Julia, Montgomery, Janet 13 July 2016 (has links)
Yes / The major components of human diet both past and present may be estimated by measuring the carbon and nitrogen isotope ratios (δ13C and δ15N) of the collagenous proteins in bone and tooth dentine. However, the results from these two tissues differ substantially: bone collagen records a multi-year average whilst primary dentine records and retains timebound isotope ratios deriving from the period of tooth development. Recent studies harnessing a sub-annual temporal sampling resolution have shed new light on the individual dietary histories of our ancestors by identifying unexpected radical short-term dietary changes, the duration of breastfeeding and migration where dietary change occurs, and by raising questions regarding factors other than diet that may impact on δ13C and δ15N values. Here we show that the dentine δ13C and δ15N profiles of workhouse inmates dating from the Great Irish Famine of the 19th century not only record the expected dietary change from C3 potatoes to C4 maize, but when used together they also document prolonged nutritional and other physiological stress resulting from insufficient sustenance. In the adults, the influence of the maize-based diet is seen in the δ13C difference between dentine (formed in childhood) and rib (representing an average from the last few years of life). The demonstrated effects of stress on the δ13C and δ15N values will have an impact on the interpretations of diet in past populations even in slow-turnover tissues such as compact bone. This technique also has applicability in the investigation of modern children subject to nutritional distress where hair and nails are unavailable or do not record an adequate period of time. / This study was supported by an Arts and Humanities Research Council grant funding to JB under AHRC Studentship AH/I503307/1.
45

Fundamental Studies on Microbial Lead Reduction and Polyhydroxyalkanoate Production / Lead bio-reduction and Polyhydroxyalkanoate Production

Amer, Abdelrahman January 2022 (has links)
Lead contamination threatens human life and the environment. The biological reduction of Pb(II) to metallic Pb is an attractive solution for Pb(II) pollution. Delftia acidovorans, Azonexus caeni, and Comamonas testosteroni were isolated and studied for their capabilities to utilize Pb(II) as a terminal electron acceptor. D. acidovorans strain Pb11 and A. caeni strain Pb2 cultures showed a 5.2- and 8.1-fold growth at 10.0 mg-Pb(II)/L in 3 d, respectively. Petroleum-based plastics are another emergent environmental concern. Polyhydroxyalkanoates (PHAs), a sustainable alternative to conventional plastics, are biodegradable polymers produced by PHA accumulators under autotrophic or heterotrophic conditions. In this thesis, the growth and enrichment of PHA accumulators, such as Plasticicumulans acidivorans and Cupriavidus necator, were investigated as they can accumulate 90% of their cell weight as PHA. An energetic model was developed to calculate theoretical PHA yields. The true autotrophic and heterotrophic PHB yields were estimated as 2.97 (g_PHB/ 〖mol〗_(H_2 )) and 0.66 (g_PHB/ g_acetate), respectively. Moreover, the growth of C. necator was investigated in lab-scale experiments under various autotrophic, heterotrophic, and mixotrophic conditions. When C. necator was cultivated in two-stage systems, high optical densities were attained in less than 24 h. In addition, a mathematical model for the competition between PHA and non-PHA accumulators in the feast-famine enrichments was developed. The calibrated and validated model for P. acidivorans suggested that microbial diversity in mixed cultures impacted the enrichment process. Another aspect of this thesis was to propose an innovative method for enriching PHA accumulators in mixed cultures. By applying autotrophic and autotrophic-heterotrophic enrichment strategies, C. necator dominated the mixed cultures (> 90%) in less than five days. Based on this thesis findings, it can be concluded that biotechnology applications in Pb(II) remediation and PHA production could reduce the severe impacts of Pb contamination, petrochemical plastics, and climate change due to elevated CO2 levels. / Thesis / Doctor of Philosophy (PhD) / This thesis aimed to provide sustainable biotechnological solutions to three environmental challenges: lead contamination, petroleum-based plastics, and elevated CO2 levels in the atmosphere. Certain metal-reducing bacteria can grow by consuming toxic Pb(II) ions from aqueous environments and thus reduce their toxicity. Furthermore, various microorganisms can store biodegradable polymers, known as polyhydroxyalkanoates (PHAs), in their cells. The stored PHA polymers can be extracted and processed to produce biodegradable plastics. PHA accumulators can produce significant amounts of PHA by utilizing organic substrates or CO2. Therefore, PHA-based plastics can reduce environmental deterioration due to non-degradable plastics and elevated CO2 levels. Lab-scale experiments and mathematical modeling can provide a better understanding of the growth and enrichment of PHA accumulators in engineered PHA-production systems. Research findings in this thesis will allow cost-effective and sustainable production of biodegradable plastics from organic wastes and flue gas.
46

Food System Reorganization and Vulnerability to Crisis: A Structural Analysis of Famine Genesis

Rice, Stian A. 23 April 2018 (has links)
No description available.
47

An isotopic and historical study of diet and migration during the great Irish Potato Famine (1845-1852) : high-resolution carbon and nitrogen isotope profiling of teeth to investigate migration and short-term dietary change at the Union workhouse, Kilkenny and Lukin street, London

Beaumont, Julia January 2013 (has links)
Historical evidence from contemporary documents established that Irish migrants to London during the Great Irish Famine (1845-1852) were likely to come from low socio-economic groups in south-west Ireland, and has characterised mid-19th-century health status and living conditions in both locations. Using samples from 119 individuals from the Catholic cemetery at Lukin Street, London (1843-1854) and 20 from the Union Workhouse Famine cemetery, Kilkenny, Ireland (1847-51), mean bone collagen isotope values were established for the well-documented Irish pre-Famine potato-based diet (δ¹⁵N 10.6‰, δ¹³C -19.1‰), and the diet of contemporaneous Londoners (δ¹⁵N 12.6‰, δ¹³C -19.1‰). The introduction of maize as a short-term Famine relief food was identified in three Kilkenny juveniles with bone collagen δ¹³C above -17‰, and incremental dentine collagen demonstrating temporal changes in δ¹³C consistent with dietary change from C3 to C4 plants. Bone collagen values for two Lukin Street individuals were consistent with high marine protein consumption. Techniques developed in this study to sample increments of dentine representing nine months or less of life have improved temporal resolution not only for migration events but also short-term dietary changes and physiological status during childhood. Combining epigraphic, osteological and archaeological evidence, individual 'lifeways' have been constructed using isotope data and provide insights into the connection between health, diet and skeletal manifestations of deprivation during childhood and adolescence. New models are investigated for examining maternal and infant health using dentine collagen increments formed in utero and combining dentine and bone collagen values to explore the effects of nutritional stress on bone turnover.
48

Freedom from Want: Famine Relief in the Horn of Africa

Ruth, Christian T. 01 January 2016 (has links)
The United States, during both the Jimmy Carter and Ronald Reagan administrations, pursued humanitarian relief in the Horn of Africa and East Africa with an eye towards Cold War politics. During the Carter administration the focus was on Ethiopia and the regime of Mengistu Haile Mariam, while during the Reagan administration the United States’ efforts were mainly targeted towards Sudan and the regime of Gaffar Nimeiry. In both instances, the United States was concerned with the politics of the Cold War, trying to create a more positive image of the U.S. abroad by relieving world hunger, while also propping up governments that supported U.S. interests during the Cold War against the Soviet Union.
49

Ice on midsummersday : -A qualtitative study on national, regional and local level of the extreme weather years and following harvest failure in 1867-68 Sweden, with focus on Gävleborgs County.

Ellen, Lindblom January 2015 (has links)
This thesis focuses on two extreme weather years in 1867-1868 that led to crop failure and subsistence crisis in parts of Sweden. Specifically it focus on Gävleborgs County and one parish, Hanebo Parish, in south west Hälsingland. The study presents contemporary examples from original sources on the national, regional and local level and one secondary source. With a qualitative approach, the study investigates the social impacts of sudden extreme weather and following harvest failure and assess signs of a possible subsistence crisis on regional and local level in the years of 1867-68. The empirics are analyzed trough demographic methodology often used to evaluate ”famine-like” situations, theories on famine and its causes and the three concepts: vulnerability, resilience and exchange entitlement. The result of the study shows a subsistence crisis in Gävleborg county and Hanebo Parish, in the years of 1867-68. These indications included poor harvest, demographic impact on parochial level and visible mitigating strategies for coping with the situation. Social hierarchies which are making impact on attitudes within the contemporary context of crisis are also discovered in the empiric material. The study also shows that state incentives and publically organised incentives can mitigate disaster both over short and long term.
50

Defining hunger, redefining food : humanitarianism in the twentieth century

Scott-Smith, Tom January 2014 (has links)
This thesis concerns the history of humanitarian nutrition and its political implications. Drawing on aid agency archives and other historical sources, it examines how food has been delivered in emergencies, from the First World War to the present day. The approach is ethnographic: this is a study of the micro-level practices of relief, examining the objects distributed, the plans made, the techniques used. It is also historical: examining how such practices have changed over time. This thesis makes five interlocking arguments. First, I make a political point: that humanitarian action is always political, and that it is impossible to adhere to ‘classical’ humanitarian principles such as neutrality, impartiality and independence. Second, I make a sociological argument: that the activities of humanitarian nutrition have been shaped by a number of themes, which include militarism, medicine, modernity, and markets. Third, I make a historical argument: that the main features of humanitarian nutrition were solidified between the 1930s and the 1970s, and were largely in place by the time of the Biafran war. Fourth, I make a sociological argument: that these mid-century changes involved a profound redefinition of hunger and food (with hunger conceived as a biochemical deficiency, and food as a collection of nutrients). Finally, I make a normative argument, suggesting that this redefinition has not necessarily benefited the starving: the provision of food in emergencies, I argue, is often concerned with control and efficiency rather than the suffering individuals themselves.

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