Humoral Immune Responses of White-Tailed Deer (Odocoileus virginianus) to Mycobacterium bovis BCG Vaccination and Experimental Challenge with M. bovis

Monitoring of the kinetics of production of serum antibodies to multiple mycobacterial antigens can be useful as a diagnostic tool for the detection of Mycobacterium bovis infection as well as for the characterization of disease progression and the efficacy of intervention strategies in several species. The humoral immune responses to multiple M. bovis antigens by white-tailed deer vaccinated with BCG orally via a lipid-formulated bait (n = 5), orally in liquid form (n = 5), and subcutaneously (n = 6) were evaluated over time after vaccination and after experimental challenge with virulent M. bovis and were compared to the responses by unvaccinated deer (n = 6). Antibody responses were evaluated by using a rapid test (RT), a multiantigen print immunoassay (MAPIA), a lipoarabinomannan enzyme-linked immunosorbent assay (LAM-ELISA), and immunoblotting to whole-cell sonicate and recombinant antigen MPB83. MAPIA and RT detected minimal to no antibody responses over those at the baseline to multiple M. bovis antigens in vaccinated white-tailed deer after challenge. This was in contrast to the presence of more readily detectable antibody responses in nonvaccinated deer with more advanced disease. The LAM-ELISA results indicated an overall decrease in the level of production of detectable antibodies against lipoarabinomannan-enriched mycobacterial antigen in vaccinated animals compared to that in nonvaccinated animals after challenge. Immunoblot data were inconsistent but did suggest the occurrence of unique antibody responses by certain vaccinated groups to Ag85 and HSP70. These findings support further research toward the improvement and potential use of antibody-based assays, such as MAPIA, RT, and LAM-ELISA, as tools for the antemortem assessment of disease progression in white-tailed deer in both experimental and field vaccine trials.

Theoretical and Experimental Studies in Nuclear Magnetic Resonance

Nuclear magnetic resonance (NMR) is a tool used to probe the physical and chemical environments of specific atoms in molecules. This research explored small molecule analogues to biological materials to determine NMR parameters using ab initio computations, comparing the results with solid-state NMR measurements. Models, such as dimethyl phosphate (DMP) for oligonucleotides or CuCl for the active site of the protein azurin, represented computationally unwieldy macromolecules. 31P chemical shielding tensors were calculated for DMP as a function of torsion angles, as well as for the phosphate salts, ammonium dihydrogen phosphate (ADHP), diammonium hydrogen phosphate, and magnesium dihydrogen phosphate. The computational DMP work indicated a problem with the current standard 31P reference of 85% H3PO4(aq.). Comparison of the calculations and experimental spectra for the phosphate salts indicated ADHP might be a preferable alternative as a solid state NMR reference for 31P. Experimental work included magic angle spinning experiments on powder samples using the UNL chemistry department’s Bruker Avance 600 MHz NMR to collect data to determine chemical shielding anisotropies. For the quadrupolar nuclei of copper and scandium, the electric field gradient was calculated in diatomic univalent metal halides, allowing determination of the minimal level of theory necessary to compute NMR parameters for these nuclei.

Northeast Research and Extension Center VIP Tour

What a pleasure it is to be with you all tonight as we celebrate achievement! It is always a joy to me to see good work, hard work, work that matters, recognized. We certainly had the opportunity to see work that matters on today's tour, and I thank our Northeast Research and Extension Center faculty for all their research and extension efforts that further our land-grant mission. I also thank the staff of the Center for their good work in support of this mission.

Panhandle Research and Extension Center Field Day

Commodity trader. Financial analyst. Human resources director. Marketing analyst. Lending officer. Stockbroker. Public relations specialist. Zookeeper. Nutritionist. These are only a few of the varied careers recent College of Agricultural Sciences and Natural Resources graduates are pursuing these days. Exciting, fulfilling careers for which the College of Agricultural Sciences and Natural Resources - we call the college CASNR for short - provides a tremendous educational base that students can build on for their lives.

Panhandle Research and Extension Center feedlot expansion dedication

Good morning. It's always a pleasure to visit western Nebraska with its wide open spaces, much of it filled with cattle. Cattle are tremendously important to Nebraska - it being our state's largest single industry. Nebraska boasts many more cattle than people - around 4 1/2 times more, counting all cattle and calves.

IANR Research and Extension Centers and their associated districts

It's a pleasure to have this opportunity to speak with you about the University’s four strategically placed Research and Extension Centers and their associated extension districts, all part of the Institute of Agriculture and Natural Resources at the University of Nebraska-Lincoln.

ESSAYS ON INTERNATIONAL RESEARCH AND DEVELOPMENT SPILLOVERS

The dissertation consists of three essays on international research and development spillovers. In the first essay, I investigate the degree to which differences in institutional arrangements among Sub-Saharan African countries determine the extent of benefits they derive from foreign research and development spillovers. In particular, I compare the international research and development spillovers for English common law and French civil law Sub-Saharan African countries. I show that differences in the legal origin of the company law or commercial codes in these countries may reflect the extent of barriers they place in the paths of firms that engage in the investment process. To tests this hypothesis, I constructed foreign R&D spillovers variable using imports as weights and employed the endogenous growth framework to estimate elasticities of productivity with respect to foreign R&D spillovers for a sample of 17 English common law and French Civil law Sub-Saharan African countries over the period 1980-2004. My results find support for the hypothesis. In particular, foreign R&D spillovers were higher in the English common law countries than in the French civil law countries. In the second essay, I examine the question of whether technical cooperation grants and overseas development assistance grants induce R&D knowledge spillovers in Sub-Saharan African countries. I test this hypothesis using data for 11 Sub-Saharan African countries over the period 1980-2004. I constructed foreign R&D spillovers using the technical cooperation grants and overseas development assistance grants as weights and employed the endogenous growth framework to provide quantitative estimates of foreign R&D spillover effects in 11 Sub-Saharan African countries. I find that technical cooperation grants and overseas development assistance grants are major mechanisms through which returns to R&D investments in G7 countries flows to Sub-Saharan African countries. However, their influence has declined over the years. Finally, the third essay tests the hypothesis that the relationship between a country's exporters and their foreign purchasing agents may lead to the exchange of ideas and thereby improve the manufacturing process and productivity in the exporting country. I test this hypothesis using disaggregated export data from OECD countries. The foreign R&D capital stock in this essay was constructed as exports weighted average of domestic R&D capital stock. I find empirical support for the hypothesis. In particular, capital goods exports generate more learning effects and therefore best explain productivity in OECD countries than non-capital goods exports.