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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.
401

Effect of Early Life Vitamin D Supplementation on Bone Development

Fielding, Kristina Anne 27 November 2013 (has links)
Vitamin D is important for bone development with immunomodulatory effects. This study investigated whether feeding CD-1 and interleukin 10 (IL-10) knockout (KO) dams low (25 IU/kg diet) or high (5,000 IU/kg diet) vitamin D affected bone health of dams as well as their offspring. Offspring were weaned to 1 of the 2 diets and followed to young adulthood. Unlike CD-1 dams, IL-10 KO dams experienced greater femur strength with high vitamin D. CD-1 male offspring had reduced femur neck strength and female offspring had smaller, weaker femurs, and weaker lumbar vertebra 2 (LV2) with high maternal vitamin D. IL-10 KO male offspring had larger femurs and female offspring had stronger femurs when weaned to high vitamin D. Low vitamin D did not adversely impact bone health but the optimal level of dietary vitamin D seems to differ between healthy and inflammatory states.
402

Effect of Early Life Vitamin D Supplementation on Bone Development

Fielding, Kristina Anne 27 November 2013 (has links)
Vitamin D is important for bone development with immunomodulatory effects. This study investigated whether feeding CD-1 and interleukin 10 (IL-10) knockout (KO) dams low (25 IU/kg diet) or high (5,000 IU/kg diet) vitamin D affected bone health of dams as well as their offspring. Offspring were weaned to 1 of the 2 diets and followed to young adulthood. Unlike CD-1 dams, IL-10 KO dams experienced greater femur strength with high vitamin D. CD-1 male offspring had reduced femur neck strength and female offspring had smaller, weaker femurs, and weaker lumbar vertebra 2 (LV2) with high maternal vitamin D. IL-10 KO male offspring had larger femurs and female offspring had stronger femurs when weaned to high vitamin D. Low vitamin D did not adversely impact bone health but the optimal level of dietary vitamin D seems to differ between healthy and inflammatory states.
403

Preconcentration Of Volatile Elements On Quartz Surface Prior To Determination By Atomic Spectrometry

Korkmaz, Deniz 01 May 2004 (has links) (PDF)
Hydride generation technique is frequently used for the detection of elements as As, Se, Sb, Sn, Bi, Ge, Te and Pb that form volatile hydrides in solution using a reductant. In this study, a novel quartz trap for on-line preconcentration of volatile analyte species was designed. Pb, Sb and Cd were selected as analyte elements and chemical vapour generation technique was employed for generation of their volatile species in flow systems. The trapping medium was formed by external heating of either the inlet arm of the quartz tube atomizer or a separate cylindirical quartz tube. Generated analyte species were trapped on quartz surface heated to the collection temperature and the collected species were revolatilized when the trap was heated further to releasing temperature and hydrogen gas was introduced in the trapping medium. The conventional quartz T-tube and multiple microflame quartz tube were employed as atomizers. The influence of relevant experimental parameters on the generation, collection and revolatilization efficiencies was investigated. Optimum conditions, performance characteristics of the trap and analytical figures of merit are presented. Experimental design was used for optimizations in some cases. Standard reference materials were analyzed to assess the accuracy of the proposed method. For a collection period of 1.0 minute for Pb, 2.0 minutes for Sb and 3.0 minutes for Cd, 3&amp / #963 / limit of detections, in pg ml-1, were 19, 3.9 and 1.8, respectively. In cases of Sb and Cd, the limits of detections obtained are the same as the best attained with in-situ trapping in graphite furnaces.
404

On-line Preconcentration Of Vapor Forming Elements On Resistively Heated W-coil Prior To Their Determination By Atomic Absorption Spectrometry

Cankur, Oktay 01 May 2004 (has links) (PDF)
Vapor generation in atomic spectrometry is a well established technique for the determination of elements that can be volatilized by chemical reactions. In-situ trapping in graphite furnaces is nowadays one of the most popular methods to increase the sensitivity. In this study, resistively heated W-coil was used as an online trap for preconcentration and revolatilization of volatile species of Bi, Cd and Pb. The collected analyte species were revolatilized rapidly and sent to a quartz Ttube atomizer for AAS measurement. Although the nature of revolatilized species of Bi and Pb are not clear, they are probably molecular since they can be transported at least 45 cm without any significant decrease in the peak height values. However, cadmium is revolatilized from the trap surface as atoms. The experimental parameters were optimized for the highest vapor generation, trapping and revolatilization efficiencies. The concentration limits of detection calculated by the 3 of blank solution were found to be 0.0027, 0.0040 and 0.015 ng/mL for Bi (18 mL), Cd (4.2 mL) and Pb (2 mL), respectively / enhancement factors in the sensitivity were 130, 31 and 20, respectively. These values are comparable with those obtained by in-situ trapping in graphite furnaces or even ICP-MS found in the literature or better. Sensitivity can be improved further for Bi and Cd using larger sample volumes, but purification of blank is required for Pb. Certified standard reference materials were analyzed for the assessment of accuracy of developed method.
405

Investigation of resonant-cavity-enhanced mercury cadmium telluride infrared detectors

Wehner, Justin January 2007 (has links)
[Truncated abstract] Infrared (IR) detectors have many applications, from homeland security and defense, to medical imaging, to environmental monitoring, to astronomy, etc. Increasingly, the wave- length dependence of the IR radiation is becoming important in many applications, not just the total intensity of infrared radiation. There are many types of infrared detectors that can be broadly categorized as either photon detectors (narrow band-gap materials or quantum structures that provide the necessary energy transitions to generate free car- riers) or thermal detectors. Photon detectors generally provide the highest sensitivity, however the small transition energy of the detector also means cooling is required to limit the noise due to intrinsic thermal generation. This thesis is concerned with the tech- nique of resonant-cavity-enhancement of detectors, which is the process of placing the detector within an optically resonant cavity. Resonant-cavity-enhanced detectors have many favourable properties including a reduced detector volume, which allows improved operating temperature, or an improved signal to noise ratio (or some balance between the two), along with a narrow spectral bandwidth. ... Responsivity of another sample annealed for 20 hours at 250C in a Hg atmosphere (ex-situ) also shows resonant performance, but indicates significant shunting due the mirror layers. There is good agreement with model data, and the peak responsivity due to the absorber layer is 9.5×103 V/W for a 100 'm ×100 'm photoconductor at 80K. An effective lifetime of 50.4 ns is extracted for this responsivity measurement. The responsivity was measured as a function of varying field, and sweepout was observed for bias fields greater than 50 V/cm. The effective lifetime extracted from this measurement was 224 ns, but is an over estimate. Photodiodes were also fabricated by annealing p-type Hg(1x)Cd(x)Te for 10 hours at 250C in vacuum and type converting in a CH4/H2 reactive ion etch plasma process to form the n-p junction. There is some degradation to the mirror structure due to the anneal in vacuum, but a clear region of high reflection is observed. Measurements of current-voltage characteristics at various temperatures show diode-like characteristics with a peak R0 of 10 G measured at 80K (corresponding to an R0A of approximately 104 cm2. There was significant signal from the mirror layers, however only negligible signal from the absorber layer, and no conclusive resonant peaks.
406

Co-stimulatory molecules : genes to protein in autoimmune and inflammatory disorders /

Sakthivel, Priya, January 2007 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.
407

Signaling in natural killer cells : SHIP, 2B4 and the Kinome

Wahle, Joseph A. January 2007 (has links)
Dissertation (Ph.D.)--University of South Florida, 2007. / Title from PDF of title page. Document formatted into pages; contains 147 pages. Includes vita. Includes bibliographical references.
408

Characterization and modelling of CEACAM1 interactions in cell signalling /

Kristmundur Sigmundsson, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
409

Hyposialylation regulates [alpha]4[beta]1 integrin binding to VCAM-1

Woodard-Grice, Alencia V. January 2008 (has links) (PDF)
Thesis (Ph.D.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed on June 29, 2009). Includes bibliographical references.
410

Usuario da busca informatizada: avaliacao do curso MEDLINE/LILACS no contexto academico

Cuenca, Angela Maria Belloni. January 1997 (has links)
Mestre -- Universidade de Sao Paulo. Faculdade de Saude Publica. Departamento de Nutricao, Sao Paulo, 1997.

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