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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

Nutrient Impacts on Rumen Growth and Development

Yohe, Taylor Timothy 19 April 2018 (has links)
Our collective knowledge of calf nutrition has evolved over the past 100+ years, but there are still areas of improvement that merit further scientific inquiry. The work described herein explored different aspects of calf nutrition with a central focus on rumen growth and development. The first study performed used 8 Holstein bull calves to determine if calf starters differing in starch and neutral detergent fiber (NDF) content would affect calf growth, intake, rumen metabolites, blood metabolites, and gross rumen measurements when fed along with milk replacer (MR). The experiment used completely pelleted calf starters consisting of ground and pelleted barley, wheat, and corn grains. Besides the high-starch starter resulting in lower rumen pH, the hypothesis that completely pelleted calf starter diets differing in NDF and starch level would alter intake, growth, rumen metabolism, and rumen measurements was not supported. However, calves fed the high-NDF starter were $5.71 less expensive per calf to raise. Findings suggest a form of feed effect in today's calf starter diets that might be of physiological and economic importance. The second study tested custom-built rumen infusion, sampling, and evacuation devices. The main objectives were to build and confirm the successful use of the devices in one Holstein bull calf at 62 days of age, which determined a liquid passage rate out of the rumen at 40.2% of ruminal fluid/h. The third and final study examined the effects of form of diet (MR only, n = 5; MR and starter, n = 6) on rumen growth and development. More specifically, isocaloric and isonitrogenous diets were fed to neonatal and ruminally cannulated Holstein calves for 6 week. The hypothesis of MR and starter calves having altered gross rumen measurements, epithelial stem and progenitor cell number, and epithelial proliferation status was supported, but hypothesized changes in volatile fatty acid (VFA) transporter abundance and VFA absorption rate were not supported. These results indicate that form of diet, even one that promotes rumen growth, does not equate to enhanced ability to absorb VFA, but there is an effect on rumen stem and progenitor cells as well as epithelial proliferation. / PHD
22

Does the choice of exchange-rate regime effect economic growth? : A study across different levels of country development

Fristedt, Sebastian January 2016 (has links)
Does the choice of exchange-rate regime effect the economic growth performance of a country? And does the significance of such a relationship vary across different levels of development? Few questions in international economics, whether it be in academic or policy circles, have inspired as much debate yielding as little consensus. Although both economic growth theory and empirical literatures suggests the existence of direct and indirect channels, through which the choice of regime may indeed impinge the growth rate, neither has managed to provide an unambiguous answer. The aim of this paper is to analyze the theoretical arguments as to the relationship between the choice of exchange-rate regime and economic growth and to empirically investigate if there is an optimal regime, in terms of growth, and if the significance of this impact differs across various levels of country development. Applying a cross-sectional regression estimation of 60 countries over the period 2000-2010, this paper finds that the choice of exchange-rate regime holds no significant explanatory power over economic growth. These findings were robust to dividing the sample based on the level of country development. Although no direct relationship was found, these findings supports the argument that the choice of regime may indeed effect growth indirectly, through its impact on other deterministic growth factors, such as trade, investment and productivity. The findings of this paper are both in accord and discord with previous results and underlines how divergent the empirical research is on this continuously debated issue.
23

Development of the skeletal musculature in the limbs of early mammalian embryos.

January 1994 (has links)
by Sze, Lung Yam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 106-112). / Abstract --- p.i / Acknowledgements --- p.iv / Contents --- p.v / Chapter Chapter 1 --- General Introduction / Chapter 1.1. --- Morphology of the Mammalian Somite and Limb --- p.1 / Chapter 1.1.1. --- The Somite --- p.1 / Chapter 1.1.2. --- The Limb --- p.3 / Chapter 1.2. --- Somite-Limb Relationship --- p.5 / Chapter 1.2.1. --- Somite Contribution to the Appendicular Musculature --- p.5 / Chapter 1.2.2. --- Somite Contribution to Limb Morphogenesis --- p.6 / Chapter 1.3. --- Control of Directionality of Somitic Cell Migration in Appendicular Environment --- p.8 / Chapter 1.4. --- Reasons and Objective of the Present Study --- p.10 / Chapter Chapter 2 --- The Origin of the Mammalian Limb Skeletal Muscles / Chapter 2.1. --- Introduction --- p.16 / Chapter 2.2. --- Materials and Methods --- p.19 / Chapter 2.2.1. --- Embryo Collection --- p.19 / Chapter 2.2.2. --- Isolation of Somites --- p.20 / Chapter 2.2.3. --- DiI-labelling of Rat Donor Somites --- p.21 / Chapter 2.2.4. --- Somite Transplantation --- p.21 / Chapter 2.2.5. --- Embryo Culture --- p.22 / Chapter 2.2.6. --- Analysis of Cultured Embryos --- p.22 / Chapter 2.2.7. --- Cryosection --- p.23 / Chapter 2.2.8. --- Limb Explant Cultures --- p.23 / Chapter 2.2.9. --- Immunohistochemistry --- p.24 / Chapter 2.2.10. --- X-gal Staining --- p.25 / Chapter 2.2.11. --- Histology --- p.25 / Chapter 2.3. --- Results --- p.27 / Chapter 2.3.1. --- Gross Morphology of Cultured Embryos --- p.27 / Chapter 2.3.2. --- Distribution of DiI Labelled Somitic Cells in Rat Embryos --- p.27 / Chapter 2.3.3. --- Histogenetic Potential of Labelled Somitic Cells in the Limbs --- p.29 / Chapter 2.3.4. --- Chimeaic Limb Culture --- p.30 / Chapter 2.4. --- Discussion --- p.32 / Chapter 2.4.1. --- Relationship Between the Somites and the Limb Musculature in Rat Embryos --- p.33 / Chapter 2.4.2. --- Myogenic Potential of Somitic Cells in the Mouse Limb Bud --- p.36 / Chapter 2.4.3. --- The Regulatory Potentials of Mammalian Somites --- p.37 / Chapter Chapter 3 --- The Migration of Somitic Cells into the Mammalian Fore- limb Bud / Chapter 3.1. --- Introduction --- p.52 / Chapter 3.2. --- Materials and Methods --- p.57 / Chapter 3.2.1. --- Embryo Collection --- p.57 / Chapter 3.2.2. --- Embryo Culture and Analysis of Cultured Embryos --- p.58 / Chapter 3.2.3. --- Experimental Series I --- p.58 / Chapter A. --- Micro-injection of DiI --- p.58 / Chapter B. --- Explant Cultures of Rat Fore-limb Bud --- p.59 / Chapter C. --- Histology and Immunohistochemistry --- p.60 / Chapter 3.2.4. --- Experimental Series II --- p.61 / Chapter A. --- Preparation of Conditioned and Unconditioned Medium --- p.61 / Chapter B. --- Coating of Nucleopore Membrane with Fibronectin --- p.62 / Chapter C. --- Preparation of Somitic Cells --- p.62 / Chapter D. --- Analysis of Chemotatic Effect --- p.63 / Chapter 3.2.5. --- Experiment Series III --- p.64 / Chapter A. --- Micro-injection of Latex Beads --- p.64 / Chapter B. --- Isolation of Somatopleure and Transplantation --- p.64 / Chapter C. --- "Somite Isolation, Labelling, and Transplantation" --- p.65 / Chapter D. --- Histology --- p.65 / Chapter 3.3. --- Results --- p.66 / Chapter 3.3.1. --- Development of Embryos In vitro --- p.66 / Chapter 3.3.2. --- Experimental Series I --- p.66 / Chapter A. --- Distribution of Somitic Cells in DiI Injected Embryos --- p.66 / Chapter B. --- Histogenetic Potential of Limb Explants Cultured Under the Kidney Capsule --- p.68 / Chapter C. --- Histogenetic Potential of Limb Explants Cultured In vitro --- p.69 / Chapter 3.3.3. --- Experimental Series II --- p.70 / Chapter A. --- Chemotatic Behaviour of Somitic Cells --- p.70 / Chapter 3.3.4. --- Experimental Series III --- p.71 / Chapter A. --- Ability of Latex Beads to Invade the Limb Bud --- p.71 / Chapter B. --- Distribution Pattern of Somatopleural and Somitic Cells --- p.71 / Chapter 3.4. --- Discussion --- p.75 / Chapter 3.4.1. --- Experimental Series I --- p.75 / Chapter A. --- Distribution of Somitic Cells in DiI-Injected Rat Embryos --- p.75 / Chapter B. --- Histogenetic Potential of Rat Fore-limb Bud --- p.77 / Chapter 3.4.2. --- Experimental Series II --- p.80 / Chapter A. --- Chemotatic Behaviour of Somitic Cells --- p.80 / Chapter 3.4.3. --- Experimental Series III --- p.80 / Chapter A. --- Ability of Latex Beads to Invade the Limb Bud --- p.80 / Chapter B. --- Ability of Somatopleure and Somite to Invade Limb Bud --- p.83 / Chapter 3.4.4. --- Conclusion --- p.83 / References --- p.106 / Appendix --- p.113
24

Regulation of eye growth in chickens.

January 1999 (has links)
Zhang Lin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 68-86). / Abstracts in English and Chinese. / ACKNOWLEDGEMENTS --- p.i / TABLE OF CONTENTS --- p.ii / ABBREVIATIONS --- p.v / LIST OF TABLES --- p.vi / LIST OF FIGURES --- p.vii / Chapter 1. --- ABSTRACT (ENGLISH/CHINESE) --- p.1 / Chapter 2. --- INTRODUCTION --- p.6 / Chapter 3. --- LITERATURE REVIEW --- p.9 / Chapter 3.1. --- MYOPIA IN HUMAN --- p.9 / Chapter 3.1.1. --- Different types of myopia --- p.9 / Chapter 3.1.2. --- The pathologic change of myopia --- p.10 / Chapter 3.1.3. --- The prevalence of myopia --- p.13 / Chapter 3.1.4. --- Hereditary influence in human myopia --- p.13 / Chapter 3.1.5. --- Environmental influence in human myopia --- p.15 / Chapter 3.1.6. --- Nutrition in human myopia --- p.16 / Chapter 3.1.7. --- Pharmacological agents used to prevent progression of myopia --- p.16 / Chapter 3.1.8. --- Contact lens in the prevention of progression human myopia --- p.17 / Chapter 3.2. --- ANIMAL MODELS OF EXPERIMENTAL MYOPIA --- p.19 / Chapter 3.2.1. --- Experimental myopia in monkeys --- p.19 / Chapter 3.2.2. --- Experimental myopia in three shrew --- p.21 / Chapter 3.2.3. --- Experimental myopia in marmosets and guinea pigs --- p.23 / Chapter 3.2.4. --- Experimental myopia in chicks --- p.24 / Chapter 3.2.5. --- Summary --- p.26 / Chapter 3.3. --- PHARMACOLOGICAL STUDIES --- p.27 / Chapter 4. --- OBJECTIVES --- p.32 / Chapter 5. --- materials and methods --- p.34 / Chapter 5.1. --- ANIMALS AND INDUCTION OF FORM DEPRIVATION MYOPIA --- p.34 / Chapter 5.2. --- EYE GROWTH AND MYOPIC STUDY --- p.35 / Chapter 5.2.1. --- Refractive measurements --- p.35 / Chapter 5.2.2. --- Ultrasonographic measurements of eye size in vivo --- p.35 / Chapter 5.2.3. --- Measurements with calipers on enucleated eyes --- p.36 / Chapter 5.2.4. --- Weight of eye globes --- p.36 / Chapter 5.3. --- RETINAL CHANGE --- p.36 / Chapter 5.3.1. --- Light microscopy --- p.36 / Chapter 5.3.2. --- Calretinin immuno-reactivity study of the myopic retina --- p.37 / Chapter 5.4. --- DETECTION OF APOPTOTIC CELL DEATH --- p.38 / Chapter 5.4.1. --- TUNEL --- p.38 / Chapter 5.5. --- EFFECT OF RETINAL TOXINS ON MYOPIC EYES --- p.39 / Chapter 5.5.1. --- Intravitreal injection of iodoacetic acid (IAA) --- p.39 / Chapter 5.5.2. --- Intravitreal injection of glutamic acid --- p.40 / Chapter 5.5.3. --- "Intravitreal injection of 5,7-dihydrowytryptamine (5,7-DHT)" --- p.40 / Chapter 5.6. --- EFFECT OF LIGHTING ON MYOPIC EYES --- p.41 / Chapter 6. --- RESULTS --- p.42 / Chapter 6.1. --- REFRACTIVE STATES --- p.42 / Chapter 6.2. --- EYE SIZE MEASUREMENTS --- p.42 / Chapter 6.2.1. --- Ultrasonographic measurements in vivo --- p.42 / Chapter 6.2.2. --- Caliper measurements of chick eyes ex vivo --- p.43 / Chapter 6.3. --- WEIGHT OF EYE GLOBES --- p.45 / Chapter 6.4. --- RETINAL CHANGE --- p.45 / Chapter 6.4.1. --- Morphological features --- p.45 / Chapter 6.4.2. --- Morphometry of calretinin immuno-positive cells --- p.46 / Chapter 6.5. --- EFFECT OF RETINAL TOXINS ON MYOPIC EYE --- p.46 / Chapter 6.5.1. --- Intravitreal injection of iodoacetic acid (IAA) --- p.46 / Chapter 6.5.1.1. --- Eye growth measurements --- p.47 / Chapter 6.5.1.2. --- Retinal histological features --- p.47 / Chapter 6.5.2. --- Intravitreal injection of glutamic acid --- p.48 / Chapter 6.5.2.1. --- Eye growth measurements --- p.48 / Chapter 6.5.2.2. --- Retinal histological features --- p.49 / Chapter 6.5.3. --- "Intravitreal injection of 5,7,-dihydrowytryptamine (5,7-DHT)" --- p.50 / Chapter 6.5.3.1. --- Eye growth measurements --- p.50 / Chapter 6.5.3.2. --- Retinal histological features --- p.50 / Chapter 6.6. --- EFFECT OF LIGHTING ON MYOPIC EYES --- p.51 / Chapter 6.6.1. --- Eye growth measurements --- p.51 / Chapter 6.6.2. --- Retinal histological features --- p.51 / Chapter 7. --- DISCUSSION --- p.53 / Chapter 7.1. --- REFRACTIVE STATES --- p.55 / Chapter 7.2. --- CHANGE IN EYE SIZE --- p.56 / Chapter 7.2.1. --- The rate of eye growth --- p.56 / Chapter 7.2.2. --- Ultrasonographic measurements --- p.57 / Chapter 7.2.3. --- Axial length change with caliper measurements --- p.58 / Chapter 7.3. --- MORPHOLOGY AND MORPHOMETRY OF MYOPIC RETINA --- p.58 / Chapter 7.4. --- EFFECT OF RETINAL TOXINS ON MYOPIC EYES --- p.60 / Chapter 7.4.1. --- Intravitreal injection of iodoacetic acid --- p.60 / Chapter 7.4.2. --- Intravitreal injection of glutamic acid --- p.61 / Chapter 7.4.3. --- "Intravitreal injection of 5,7-DHT" --- p.63 / Chapter 7.5. --- EFFECT OF LIGHTING ON MYOPIC EYES --- p.64 / Chapter 8. --- CONCLUSION --- p.66 / BIBLIOGRAPHY --- p.68
25

Cellular and molecular bases of apoptosis in the interdigital tissues of developing mouse limbs. / CUHK electronic theses & dissertations collection

January 1999 (has links)
by Tang Mei Kuen. / "May 1999." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (p. 134-179). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
26

Fetal thyroid volume in the normal and thyrotoxic pregnancies.

January 1997 (has links)
Ho Sin Yee, Stella. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 94-105). / Background --- p.1 / Chapter Chapter 1 --- Introduction / Thyrotoxicosis --- p.3 / Graves' Disease --- p.5 / Laboratory Assessment of the Mothers --- p.7 / Placental Transfer --- p.10 / Effects of Maternal Thyroid and Antithyroid Agents on the Fetus --- p.13 / Diagnostic and Screening Tests for Fetal Thyroid Dysfunction --- p.19 / Fetal Treatment --- p.21 / Aims and Objectives of the Research --- p.24 / Chapter Chapter 2 --- Subjects and Methods / Patients' Profile --- p.26 / Categorization of the Thyrotoxic Population --- p.28 / Intraobserver Error --- p.30 / Pilot Study --- p.31 / Equipment --- p.31 / Measurements --- p.32 / Growth Charts employed --- p.32 / Imaging Technique --- p.33 / Calculations --- p.39 / Gestational Age of the Fetus --- p.41 / Analytical Methods --- p.43 / Chapter Chapter 3 --- Results / Intraobserver Error --- p.45 / Pilot Study --- p.45 / Maternal Thyroid Status (Thyrotoxic Population) --- p.48 / Fetal Thyroid Volume --- p.49 / Rate of Fetal Thyroid Growth --- p.59 / Fetal Thyroid Volume to Estimated Fetal Weight Ratios (V/W) --- p.60 / Birthweight of the Infants --- p.63 / Chapter Chapter 4 --- Discussion / Methodology --- p.64 / Findings and Observations --- p.71 / Chapter Chapter 5 --- Conclusions --- p.92 / References --- p.94 / Appendix I --- p.106
27

The Impact of Regional Return on Education on the Self-selection of Mexican Immigrants

Chen, Warren 01 January 2019 (has links)
This paper uses the 2010 Mexican Population and Housing Survey to examine the role of regional return to education on migrant selection. The study uses a standard linear regression model to predict the educational attainment of migrants and compares it to the educational attainment of non-migrants in each Mexican State. It finds evidence of negative selection, that less educated Mexican citizens are more likely to migrate to the United States. It also finds little evidence of the impact of regional return to education on migrant selection. The study offers potential explanations for the lack of impact and suggests avenues for continued study.
28

Essays on Trade and Growth

Hou, Yulin 06 June 2018 (has links)
This dissertation is composed of three essays on international trade and economic growth. The first essay investigates whether the content of what economies export matters for human capital accumulation. I construct a small open economy model and find that expansion of primary exports can harm human capital accumulation if the economy is initially allocating significant resources to primary goods production. Then I test this prediction empirically using Latin American data over the period from 1965 to 2010 and find robust evidence in support of the hypothesis that a shift towards primary exports reduces human capital accumulation. In the second essay, I investigate the effects of gravity variables (distance, common border, colony relationship, free trade agreement, or language) on preference and trade costs. This essay models the imports of the U.S. at the individual good level and uses the three-stage least square regression approach by focusing on the trade elasticities. Using actual data on trade costs, this essay decomposes the overall effects of gravity variables on trade into those through gravity channels: duties/tariffs, transportation costs, and dyadic-preference. The results imply that gravity variables mainly capture the effect of preference rather than trade costs (as implied by the existing literature). In the final essay, I examine the effects of increased demand from China on economic growth of the Latin American and the Caribbean (LAC) countries. This essay views the increased Chinese demand in the early 2000s as a quasi-natural experiment and considers it as a “treatment” to which a part of the LAC region was subjected. I adopt a difference-in-difference framework and find that China's demand did deliver significantly higher growth rates to LAC exporters over the last decade and a half.
29

Studies on the differences between in-vivo and in-vitro matured mouse oocytes priming with or without gonadotropins

Wang, Yue, 1973 Aug. 1- January 2007 (has links)
No description available.
30

Control of Plant Development by Light, CO2 and Oligosaccharins in vitro

Miranda, J. Unknown Date (has links)
No description available.

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