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Title: Michigan State University African Studies Director David Wiley interviews MSU Professor Emeritus David Dwyer and his wife Annabel on their education, work in Africa, political activism, and history of African studies at MSU
Creator: Dwyer, David J.
Date: 2006-10-20
Collection: G. Robert Vincent Voice Library Collection
Description: Dr. David Dwyer, Professor Emeritus of Anthropology, Linguistics and African Studies and his wife Annabel are interviewed by Dr. David Wiley, Director of the MSU African Studies Center. Dwyer talks about his youth, education and first jobs. Annabel talks about joining the Peace Corps and credits David Dwyer and his family for being instrumental in the creation of the Peace Corp. She recalls working in Cameroon in the early 1960s, meeting and marrying David, coming to East Lansing, and earning...
Show moreDr. David Dwyer, Professor Emeritus of Anthropology, Linguistics and African Studies and his wife Annabel are interviewed by Dr. David Wiley, Director of the MSU African Studies Center. Dwyer talks about his youth, education and first jobs. Annabel talks about joining the Peace Corps and credits David Dwyer and his family for being instrumental in the creation of the Peace Corp. She recalls working in Cameroon in the early 1960s, meeting and marrying David, coming to East Lansing, and earning a Masters in Urban Planning from MSU. The Dwyers reflect on working in West African countries just after the end of colonial rule and describe the creation of the African Language Program at MSU. Both reflect on their antiwar activities, founding the Peace Education Center in East Lansing, and the African Studies Center at MSU. They also talk about their anti-Apartheid work, political activism in general and how they plan to spend their retirement years. Part of the African Studies Interview Series sponsored by the MSU Libraries and the African Studies Center.
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Title: Michigan State University Distinguished Professor Emeritus John M. Hunter talks about his reearch done in Africa
Creator: Hunter, John M. (John Melton), 1928-2016
Date: 2003-05-19
Collection: G. Robert Vincent Voice Library Collection
Description: Peter Limb, Michigan State University Librarian and Africana Bibliographer introduces David Robinson, University Distinguished Professor of History and David Wiley, Director of the MSU African Studies Center who both interview John M. Hunter, University Distinguished Professor Emeritus of Geography. Hunter tells of his field research in the Gold Coast, Ghana, Sierra Leone, Gambia, and Nigeria in the mid-1950s, while serving as an MSU professor abroad. He also discusses the census mapping...
Show morePeter Limb, Michigan State University Librarian and Africana Bibliographer introduces David Robinson, University Distinguished Professor of History and David Wiley, Director of the MSU African Studies Center who both interview John M. Hunter, University Distinguished Professor Emeritus of Geography. Hunter tells of his field research in the Gold Coast, Ghana, Sierra Leone, Gambia, and Nigeria in the mid-1950s, while serving as an MSU professor abroad. He also discusses the census mapping model he developed and used in Ghana in 1960, which was funded by UNESCO and became a model used in many African countries. Other topics covered include medical geography, socio-economic geography, river blindness, schistosomiasis, elephantiasis, guinea worm disease and seasonal hunger.
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Title: Michigan State University Distinguished Professor Dr. Richard E. Lenski talks about his life and academic career
Creator: Lenski, Richard
Date: 2013-07-25
Collection: G. Robert Vincent Voice Library Collection
Description: Michigan State University Distinguished Professor Dr. Richard E. Lenski talks about his appointment to two different departments at MSU, his childhood in Ann Arbor and Chapel Hill, attending Oberlin College as a biology major, and studying the interplay of evolution and ecology in graduate school at the University of North Carolina - Chapel Hill. He also describes his career before coming to MSU and says that he finds the MSU community to be incredibly supportive and East Lansing to be a...
Show moreMichigan State University Distinguished Professor Dr. Richard E. Lenski talks about his appointment to two different departments at MSU, his childhood in Ann Arbor and Chapel Hill, attending Oberlin College as a biology major, and studying the interplay of evolution and ecology in graduate school at the University of North Carolina - Chapel Hill. He also describes his career before coming to MSU and says that he finds the MSU community to be incredibly supportive and East Lansing to be a wonderful place to live. He ends by describing some of the awards he has received and discusses his concerns for the future of science and research. Lenski is interviewed by former MSU Professor Pauline Adams for the Michigan State University Faculty Emeriti Association Oral History Project.
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Title: Darwin's semantic voyage : exploration and exploitation of Victorian science in the reading notebooks
Creator: Allen, Colin
Date: 2015-10-23
Collection: G. Robert Vincent Voice Library Collection
Description: Colin Allen, provost professor at the University of Indiana Bloomington, delivers a talk titled "Darwin's Semantic Voyage: Exploration and Exploitation of Victorian Science in the Reading Notebooks." Allen discusses his research project in which the full text of 670 books found in Charles Darwin's reading notebooks is analyzed by using topic modeling to explore the semantic distance between each book in the notebook. Allen rigorously describes the methodology behind topic modeling and the...
Show moreColin Allen, provost professor at the University of Indiana Bloomington, delivers a talk titled "Darwin's Semantic Voyage: Exploration and Exploitation of Victorian Science in the Reading Notebooks." Allen discusses his research project in which the full text of 670 books found in Charles Darwin's reading notebooks is analyzed by using topic modeling to explore the semantic distance between each book in the notebook. Allen rigorously describes the methodology behind topic modeling and the algorithms which his team used to produce their results and details the ways in which the results have aided in understanding Darwin's influences and research patterns over the course of his career. Allen answers questions from the audience. Part of the Michigan State University Libraries Colloquia Series, cosponsored by the Philosophy Department and the Digital Humanities Program in the College of Arts and Letters. Held in the MSU Main Library.
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Title: John Revitte, Michigan State University Professor of Human Resources and Labor Relations, talke about research he and Ken Germanson have conducted on the Allied Industrial Workers
Creator: Revitte, John
Date: 2012-05-23
Collection: G. Robert Vincent Voice Library Collection
Description: John Revitte, Michigan State University Professor of Human Resources and Labor Relations, presents some of the research he and Ken Germanson have conducted looking at the Allied Industrial Workers union and their relationships with the UAW-AFL, the UAW-CIO, and additional research he hopes to conduct into the stories of the parts supplier industries and the AIW. Germanson introduces Revitte and several others join the conversation. Revitte asks for their assistance to find memorabilia of the...
Show moreJohn Revitte, Michigan State University Professor of Human Resources and Labor Relations, presents some of the research he and Ken Germanson have conducted looking at the Allied Industrial Workers union and their relationships with the UAW-AFL, the UAW-CIO, and additional research he hopes to conduct into the stories of the parts supplier industries and the AIW. Germanson introduces Revitte and several others join the conversation. Revitte asks for their assistance to find memorabilia of the unions and coaches them on where to look. They reminisce about some high and low points in the unions and some of the past and present struggles faced by workers.
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Title: Labor leader Ken Germanson talks with Michigan State University Labor and Industrial Relations Professor Emeritus John Revitte via telephone. 2018-02-21
Creator: Germanson, Kenneth
Date: 2018-02-21
Collection: G. Robert Vincent Voice Library Collection
Description: Ken Germanson, Allied Industrial Workers international union staff member, AIW newspaper editor, and president of the Wisconsin Labor History Society (WLHS), talks with Michigan State University Labor and Industrial Relations Professor Emeritus John Revitte via telephone. They talk about projects they might partner on about the AIW and labor history, upcoming conferences they will attend, the split within the AIW between those allied with the CIO and those backing the AFL, and how a...
Show moreKen Germanson, Allied Industrial Workers international union staff member, AIW newspaper editor, and president of the Wisconsin Labor History Society (WLHS), talks with Michigan State University Labor and Industrial Relations Professor Emeritus John Revitte via telephone. They talk about projects they might partner on about the AIW and labor history, upcoming conferences they will attend, the split within the AIW between those allied with the CIO and those backing the AFL, and how a corruption scandal affected one section of the AIW while the majority of the union was clean. Revitte also shares a story of his efforts to unionize graduate students at University of Massachusetts-Amherst and talks about his own career path.
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Title: Michigan State University Africana Librarian Joe Lauer is interviewed by Peter Limb about Lauer's career at Michigan State and the development of the Africana Collection at the MSU Libraries
Creator: Lauer, Joseph J.
Date: 2015-10-27
Collection: G. Robert Vincent Voice Library Collection
Description: Michigan State University Africana Librarian Joe Lauer is interviewed by Peter Limb about Lauer's career at Michigan State and the development of the Africana Collection at the MSU Libraries. Lauer discusses the history of the International Library within the MSU Libraries and how MSU's involvement with the University of Nigeria at Nsukka during the 1960's created a demand by faculty for more books about Africa. Lauer talks about his own interest in African Studies, how he came to work at...
Show moreMichigan State University Africana Librarian Joe Lauer is interviewed by Peter Limb about Lauer's career at Michigan State and the development of the Africana Collection at the MSU Libraries. Lauer discusses the history of the International Library within the MSU Libraries and how MSU's involvement with the University of Nigeria at Nsukka during the 1960's created a demand by faculty for more books about Africa. Lauer talks about his own interest in African Studies, how he came to work at Michigan state and describes projects that he has been involved in over the years, both at MSU and on a national level. Lauer and Limb, who is also an MSU Africana Librarian, also discuss the challenges and rewards associated with Africana librarianship, focusing specifically on collection development and cataloging. Part of the African Studies Interview Series sponsored by the MSU Libraries and the MSU African Studies Center.
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Title: Electronic structure and excited state dynamics of chromium(III) complexes
Creator: Schrauben, Joel Nicholas
Date: 2010
Collection: Electronic Theses & Dissertations

Title: The effect of growth-restriction on voluntary physical activity engagement in mice
Creator: Leszczynski, Eric
Date: 2019
Collection: Electronic Theses & Dissertations
Description: INTRODUCTION. Current evidence suggests that early life growth restriction reduces physical activity engagement. Therefore, the purpose of this investigation was to examine the effects of early life growth-restriction on levels of wheel running in mice, and determine if known biological mechanisms regulate physical activity engagement. METHODS. Using a cross-fostering, protein-restricted nutritive model, mice were growth-restricted during either gestation (GUN; N = 3 litters) or postnatal...
Show moreINTRODUCTION. Current evidence suggests that early life growth restriction reduces physical activity engagement. Therefore, the purpose of this investigation was to examine the effects of early life growth-restriction on levels of wheel running in mice, and determine if known biological mechanisms regulate physical activity engagement. METHODS. Using a cross-fostering, protein-restricted nutritive model, mice were growth-restricted during either gestation (GUN; N = 3 litters) or postnatal life (PUN; N = 3 litters), along with a well fed control group (CON; N = 3 litters). At 21 days of age, all mice pups were weaned and fed a non-restrictive healthy diet for the remainder of the study. At 45 days of age mice were individually housed in cages with free moving running wheels to assess physical activity engagement. At day 70, mice were euthanized, and the nucleus accumbens was analyzed for dopamine receptor 1 expression. Skeletal muscle fiber type and cross-sectional area of the soleus, extensor digitorom longus, and diaphragm were analyzed by immunohistochemistry. The soleus from the other hind leg was evaluated for calsequestrin 1 and annexin A6 expression. RESULTS. The PUN female mice had a reduction (P = 0.0221) in wheel revolutions per day as compared to the GUN and CON females. PUN female mice also expressed significantly higher Drd1(P = 0.0247) and Casq1 (P = 0.0398) compared to the other groups. CONCLUSION. Growth-restriction during lactation reduced physical activity in female mice by reducing the central drive to be active and displayed a more fatigable skeletal muscle phenotype.
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Title: A study of water vapor transmission rate of blister packs by USP standard and continuous gravimetric protocol
Creator: Mehrotra, Nikhil
Date: 2010
Collection: Electronic Theses & Dissertations
Description: The water vapor transmission rate (WVTR) is essential in determining the shelf life of pharmaceutical products in the package. The WVTR of blister pack was determined by using USP 671 and the continuous gravimetric protocols. The WVTR values from the two protocols were compared and the accuracy was validated.The WVTR of the blister pack determined using the USP 671 protocol was 0.0452 mg/day/blister with a standard error of 0.0010 while the WVTR using the continuous gravimetric protocol was 0...
Show moreThe water vapor transmission rate (WVTR) is essential in determining the shelf life of pharmaceutical products in the package. The WVTR of blister pack was determined by using USP 671 and the continuous gravimetric protocols. The WVTR values from the two protocols were compared and the accuracy was validated.The WVTR of the blister pack determined using the USP 671 protocol was 0.0452 mg/day/blister with a standard error of 0.0010 while the WVTR using the continuous gravimetric protocol was 0.0652 mg/day/blister with a standard error of 0.0067. The WVTR were compared using t-statistic for unequal sample size with unequal variance and no significant difference was detected. The accuracy of the two protocols was compared through the pooled variance of the data points and it was found that the USP 671 standard protocol had a pooled variance of 4.99 x 10-4 while for the continuous gravimetric protocol it was 2.13 x 10-5. Therefore the continuous gravimetric protocol showed higher accuracy than the USP standard protocol Several recommendations have been suggested for the USP standard protocol in order to make the protocol more accurate: To determine the WVTR of the blister pack, the unsteady state should be considered and excluded from the calculation, Monitoring of the relative humidity and temperature throughout the experiment is critical, Chamber size and the time of equilibrium for the specific relative humidity needs to be outlined.
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Title: Theoretical analysis of electronic, thermal, and mechanical properties in gallium oxide
Creator: Domenico Santia, Marco
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In recent years, Ga2O3 has proven to be a promising semiconductor candidate for a widearray of power electronics and optoelectronics devices due to its wide bandgap, high breakdownvoltage, and growth potential. However, the material suffers from a very low thermalconductivity and subsequent self-heating issues. Additionally, the complexity of the crystalstructure coupled with the lack of empirical data, has restricted the predictive power of modellingmaterial properties using traditional...
Show moreIn recent years, Ga2O3 has proven to be a promising semiconductor candidate for a widearray of power electronics and optoelectronics devices due to its wide bandgap, high breakdownvoltage, and growth potential. However, the material suffers from a very low thermalconductivity and subsequent self-heating issues. Additionally, the complexity of the crystalstructure coupled with the lack of empirical data, has restricted the predictive power of modellingmaterial properties using traditional methods. The objective of this dissertation is toprovide a detailed theoretical characterization of material properties in the wide bandgapsemiconductor Ga2O3 using first-principles methods requiring no empirical inputs. Latticethermal conductivity of bulk β − Ga2O3 is predicted using a combination of first-principlesdetermined harmonic and anharmonic force constants within a Boltzmann transport formalismthat reveal a distinct anisotropy and strong contribution to thermal conduction fromoptical phonon modes. Additionally, the quasiharmonic approximation is utilized to estimatevolumetric effects such as the anisotropic thermal expansion.To evaluate the efficacy of heat removal from β − Ga2O3 material, the thermal boundaryconductance is computed within a variance-reduced Monte-Carlo framework utilizingfirst-principles determined phonon-phonon scattering rates for layered structures containingchromium or titanium as an adhesive layer between a β − Ga2O3 substrate and Au contact.The effect of the adhesive layer improves the overall thermal boundary conductancesignificantly with the maximum value found using a 5 nm layer of chromium, exceeding themore traditional titanium adhesive layers by a factor of 2. This indicates the potential ofheatsink-based thermal management as an effective solution to the self-heating issue.Additionally, this dissertation provides a detailed characterization of the effect of strainon fundamental material properties of β−Ga2O3 . Due to the highly anisotropic nature of thecrystal, the effect strain can have on electronic, mechanical, and optical properties is largelyunknown. Using the quasi-static formalism within a DFT framework and the stress-strainapproach, the effect of strain can be evaluated and combined with the anisotropic thermalexpansion to incorporate an accurate temperature dependence. It is found that the elasticstiffness constants do not vary significantly with temperature. The computed anisotropyis unique and differs significantly from similar monoclinic crystal structures, indicating theimportant role of the polyhedral linkage to the reported anisotropy in material properties.Lastly, the dependence of the dielectric function with respect to strain is evaluated using amodified stress-strain approach. This elasto-optic, or photoelastic, effect is found to be significantfor sheared crystal configurations. This opens up a potential unexplored applicationspace for Ga2O3 as an acousto-optic modulation device
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Title: I. Delivery of carbohydrate antigens by glycopolymers as potential anti-cancer vaccines : II. A study of the impacts of valency and density on immune response against a tumor associated carbohydrate antigen
Creator: Qin, Qian, 1981-
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Tumor associated carbohydrate antigens (TACAs) are overexpressed on tumor cells, which renders them attractive targets for anti-cancer vaccines. To overcome the poor immunogenecity of TACAs, a polymer platform was designed for antigen presentation by taking advantage of the polymeric backbone to deliver TACA and helper T (Th) cell epitope on the same chain. The block copolymer was synthesized by cyanoxyl-mediated free radical polymerization followed by conjugation with a TACA Tn antigen and a...
Show moreTumor associated carbohydrate antigens (TACAs) are overexpressed on tumor cells, which renders them attractive targets for anti-cancer vaccines. To overcome the poor immunogenecity of TACAs, a polymer platform was designed for antigen presentation by taking advantage of the polymeric backbone to deliver TACA and helper T (Th) cell epitope on the same chain. The block copolymer was synthesized by cyanoxyl-mediated free radical polymerization followed by conjugation with a TACA Tn antigen and a mouse Th-cell peptide epitope derived from poliovirus (PV) to afford the vaccine construct. The glycopolymer vaccine elicited a robust immune response with significant titers of IgG antibodies and the antibodies generated recognized Tn antigens on tumor cell surface. For successful carbohydrate based anti-cancer vaccines, it is critical that B cells are activated to secret antibodies targeting TACAs. Despite the availability of many TACA based constructs, systematic understanding of the effects of structural features on anti-glycan antibody responses is lacking. In this study, a series of defined synthetic glycopolymers bearing a representative TACA, i.e., the Thomsen-nouveau (Tn) antigen, have been prepared to probe the induction of early B cell activation and antibody production via a T cell independent mechanism. Valency and density of the antigen in the polymers turned out to be critical. An average of greater than 6 Tn per chain was needed to induce antibody production. Glycopolymers with 40 antigens per chain and backbone molecular weight of 450 kDa gave the strongest stimulation to B cells in vitro, which correlated well with its in vivo activity. Deviations from the desired valency and density led to decreased antibody production or even antigen specific B cell non-responsiveness. These findings provide important insights on how to modulate anti-TACA immune responses facilitating the development of TACA based anti-cancer vaccines using glycopolymers.
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Title: Quantifying groundwater recharge dynamics using a process-based distributed hydrologic model
Creator: Kang, Guoting
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Groundwater--the lifeblood of groundwater-dependent ecosystems and societies--is facing unprecedented threats from over-extraction, contamination, and changing climate. Groundwater recharge provides a sustainable source of water for aquifers and plays an important role in both surface and sub-surface domains. Understanding and accurately estimating the rate, location, and timing of major recharge events and their seasonal and inter-annual variability is key to safely matching societal needs...
Show moreGroundwater--the lifeblood of groundwater-dependent ecosystems and societies--is facing unprecedented threats from over-extraction, contamination, and changing climate. Groundwater recharge provides a sustainable source of water for aquifers and plays an important role in both surface and sub-surface domains. Understanding and accurately estimating the rate, location, and timing of major recharge events and their seasonal and inter-annual variability is key to safely matching societal needs of water and to maintaining healthy groundwater-dependent ecosystems. This work attempts to understand and quantify recharge dynamics in an agricultural watershed in the Ottawa County, Michigan using field observations of baseflows, groundwater heads, satellite-based evapotranspiration (ET) products and an integrated, process-based hydrologic model. Specific objectives of the work are to: (1) understand the spatial and temporal distribution of high- and low-recharge events and (2) assess the relative impacts of climate, land use, soils, and topography on the spatiotemporal distribution of recharge within the region. County-wide synoptic and time-series baseflow data collected from over 40 small streams between July and November of 2015 were used to quantify the uncertainties in recharge estimation. Precipitation data represent important inputs to hydrologic models and have a major influence on model performance and the estimated recharge. Compared to data from a typical network of rain gauges, the Next-Generation Weather Radar (NEXRAD) provides precipitation data at a much higher spatial resolution. NEXRAD data were blended with traditional rain gauge data to estimate recharge and to evaluate differences relative to recharge estimated using rain gauge data alone. Results indicate that caution should be exercised in using NEXRAD precipitation data for recharge estimation. The representation of recharge and its variability within a numerical model are closely related to the representation of meteorological forcing fields and their spatial structure, land use and land cover, the hydraulic properties of underlying soils and aquifers as well as topography--all of which are represented to varying degrees of accuracy depending on the mesh resolution employed and the algorithms used to represent sub grid-scale processes. To understand the effects of grid resolution on recharge and to identify optimal resolution relative to the size of the watershed, models were setup with different grid resolutions. Recharge patterns follow precipitation patterns more closely at coarse grid sizes since the characteristics of LULC, terrain and hydraulic properties are smoothed at this resolution. Insights gained from the study are expected to aid in the sustainable management of natural resources, particularly groundwater-dependent ecosystems.
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Title: Sweet nanomedicine in vivo : glyconanoparticle for imaging amyloid beta fibrils in Alzheimer's disease, and hyaluronan nanoparticles for imaging and therapy of inflammatory Atherosclerosis disease
Creator: Hossaini Nasr, Seyedmehdi
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation is about design and synthesis of glyconanoparticles for certain in vivo applications including imaging amyloid beta fibrils in Alzheimer’s disease, imaging inflammatory atherosclerotic plaques and inhibition of atherosclerotic plaque inflammation. Amyloid beta (Aβ) accumulation and deposition in the brain tissue are one of the most important hallmarks of Alzheimer’s disease (AD). Therefore, Aβ is an attractive target for imaging AD, however, designing a nanoprobe with the...
Show moreThis dissertation is about design and synthesis of glyconanoparticles for certain in vivo applications including imaging amyloid beta fibrils in Alzheimer’s disease, imaging inflammatory atherosclerotic plaques and inhibition of atherosclerotic plaque inflammation. Amyloid beta (Aβ) accumulation and deposition in the brain tissue are one of the most important hallmarks of Alzheimer’s disease (AD). Therefore, Aβ is an attractive target for imaging AD, however, designing a nanoprobe with the ability to pass through the blood brain barrier (BBB) and reaching Aβ plaques is a significant challenge. The first part of this dissertation covers the synthesis of a glyconanoparticle enabling to pass the BBB and bind with Aβ fibrils. Briefly, synthesis, characterization and application of this glyconanoparticle for magnetic resonance imaging (MRI) of Aβ plaques in a mouse model of AD (B6C3) have been presented. Majority of patients that experience cardiac arrests have atherosclerosis, which is the inflammatory disease of arterial walls and the major cause of heart attacks and strokes. Imaging techniques that can enable detection of atherosclerotic plaques before clinical manifestation are urgently needed. CD44 is a cell surface protein overexpressed in the plaque tissues and its expression level is associated with the risk of plaque rupture. The second chapter explains atherosclerosis disease and nanomedicine for targeting inflammatory atherosclerotic plaques. The third chapter of this dissertation presents the development of hyaluronan (HA) coated iron oxide nanoparticles for active targeting of the plaques. These nanoprobes can not only bind with atherosclerotic plaques through their HA ligands but also function as T2 based MRI contrast agents for plaque diagnosis. Moreover, the effect of nanoprobe morphology on inflammation has been studied indicating that engineering nanoprobe shape could decrease inflammatory responses, which makes it a superior candidate for imaging inflammatory atherosclerotic plaques. Concisely, design and synthesis of HA conjugated nanoworm (HA-NW) have been explained. Then, inflammatory responses to HA conjugated nanoparticles in vitro and in vivo in apoE knockout mouse model have been presented. Finally, the ability of HA-NW for in vivo imaging of atherosclerotic plaques by MRI has been studied.The last part of this dissertation goes over design and synthesis of hyaluronan conjugated atorvastatin nanoparticle (HA-ATV NP). This therapeutic formulation has been designed to deliver ATV to the inflammatory atherosclerotic plaques to reduce plaque inflammation. Then, HA-ATV NP anti-inflammatory effects in vitro and its therapeutic effect in vivo in apoE knockout mouse model have been explained. It has been shown that intravenous administration of this formulation (high dose, 8.5 mg ATV/ kg), every other day for one week can significantly reduce the plaques inflammation.
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Title: Integrated remote sensing and crop system modeling for precision agriculture across spatial and temporal scales
Creator: Peter, Bradley George
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In light of global environmental change, population pressure, and food production demands, there is considerable value in mapping biogeographic crop niche and characterizing crop productivity at multiple scales to enhance the impact of agricultural improvement across Africa. Crop system research has advanced sustainable strategies for intensifying food production; however, questions regarding where to implement innovative technologies are largely unresolved.This dissertation focuses on four...
Show moreIn light of global environmental change, population pressure, and food production demands, there is considerable value in mapping biogeographic crop niche and characterizing crop productivity at multiple scales to enhance the impact of agricultural improvement across Africa. Crop system research has advanced sustainable strategies for intensifying food production; however, questions regarding where to implement innovative technologies are largely unresolved.This dissertation focuses on four geographic questions: (1) Where is the fundamental climate niche of maize, pigeonpea, and sorghum across Africa? (2) Where are marginal lands in Malawi and what are the underlying drivers of marginality? (3) Based on the drivers of marginal maize production, what are geographic scaling options for integration of pigeonpea into maize-based cropping systems? (4) What spatial resolutions are effective for conducting precision agriculture at the farm scale in smallholder systems? Overarching themes within the geographic discipline such as the modifiable areal unit problem and ecological fallacy problem underpin this research. Marginal areas for maize are highlighted at the Africa and Malawi scales and overlain with the optimal climate niche for crops such as sorghum and pigeonpea that offer multiple ecosystem services (e.g., soil rehabilitation through nitrogen fixation). Crop productivity is evaluated at scales relative to policy making delineations in Malawi (i.e., country, district, and extension planning area) to disentangle heterogeneity at local scales that may appear homogeneous at broader scales. At the Malawi farm scale, this research included the use of a small unmanned aerial system (sUAS), national government satellites (e.g., Sentinel-2), and commercial satellites (e.g., SPOT 6). Spectral measurements of crop status were evaluated at multiple spatial resolutions (ranging from 0.07-20-m) to determine what spatial resolutions and what spectral indices are most effective for estimating crop yields and crop chlorophyll.Results of this research include high spatial resolution maps of maize, pigeonpea, and sorghum suitability across Africa, indicating that pigeonpea and sorghum occupy unique agroecological zones throughout the continent (e.g., sorghum in the Sahel region). Similarly, pigeonpea suitability in Malawi occupies a greater land area than the extent to which it is currently cultivated, demonstrating that integration into maize-based cropping systems, particularly where soil is marginal, can have beneficial scaling outcomes. For the smallholder farm scale, problems of clouds and satellite revisit rates have not yet been overcome for precision agriculture. In this regard, sUAS are a promising option for relating spectral signals to on-farm measurements of crop status. Evidence from drone flights conducted at two experimental farms in the central region of Malawi (Nyambi and Ntubwi) suggest that spatial resolutions closer to the plant scale (i.e., 14-27-cm) are most effective for relating spectral imagery to crop status. Moreover, the green normalized difference vegetation index (GNDVI) and green soil adjusted vegetation index (GSAVI) were consistently correlated with crop chlorophyll and yield, illustrating that a broad range of indices should be evaluated for precision agriculture.
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Title: Trajectories of mental health and the impact of economic well-being across middle aged adults
Creator: Lee, Jaewon
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Mental health is one of several important factors to sustain one's well-being, and as such, poor mental health can lead to significant problems in one’s quality of life. Although mental illnesses are prevalent in middle-aged adults and the importance of mental health in general has been discussed in many studies, mental health across middle-aged adults has received less attention. Levels of depression have changed over time and lack of economic resources influences mental health. The purpose...
Show moreMental health is one of several important factors to sustain one's well-being, and as such, poor mental health can lead to significant problems in one’s quality of life. Although mental illnesses are prevalent in middle-aged adults and the importance of mental health in general has been discussed in many studies, mental health across middle-aged adults has received less attention. Levels of depression have changed over time and lack of economic resources influences mental health. The purpose of this study is to examine trajectories of mental health among middle-aged adults, to investigate which factors influence the trajectories of mental health, and to explore the effects of economic well-being on mental health during middle age. The National Longitudinal Survey of Youth 1979 (NLSY79), which is a nation-wide representative data set for individuals in the United States, was used for analysis. A sample of 834 individuals who discussed their mental health status at four points in time (34, 36, 40, and 50 years of age) was analyzed. The latent growth model was conducted using M-plus statistical package. The research questions are as follows: 1) What are the trajectories of mental health among middle aged-adults (34 to 50 years of age)? 2) Is economic well-being (net worth and employment) associated with mental health? Major findings reported in this study were that the trajectories of mental health show non-linear change, with lowest levels of depression at 40 and higher levels of depression at 34, 36, and 50 years of age. Male, self-esteem, cognitive ability, health insurance, employment, and net worth predicted lower intercepts of depression. In addition, even after including time-varying covariates, the trajectories of mental health still show non-linear change. Employment was associated with lower risks of depression at 34, 36, 40, and 50 years, and net worth was also associated with lower risks of depression at 34, 36, and 50 years. This study confirms the trajectories of mental health among middle-aged American adults within longitudinal setting by using four waves. Compared to previous studies, which have been primarily conducted with a cross-sectional approach, this study contributes further evidence in understanding trajectories of mental health among middle-aged adults. In addition, the findings support the hypothesis that employment and net worth have a significant impact on mental health during middle age. Middle age is a stage greatly influenced by economic resources as individuals become more responsible for their lives at an economic level and face economic challenges that can ultimately affect depression. Understanding the effects of economic well-being on depression among middle-aged adults helps to pinpoint a specific period of time for interventions to improve poor mental health. This period of time in life may thus require more attention and care before levels of depression begin to increase. The findings provide a rationale, which calls for increased job and job training opportunities, as well as educational programs regarding saving and wealth accumulation in order to improve poor mental health and achieve social justice. Furthermore, it provides grounds for social workers to further advocate for and protect individuals who suffer from mental health and have poor economic well-being.
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Title: A comparison of deer census methods in the Rifle River game area
Creator: Howe, Duane Lawson
Date: 1954
Collection: Electronic Theses & Dissertations

Title: Investigations of aquaculture methodologies to enhance success of Great Lakes lake sturgeon streamside facilities
Creator: Bauman, John Matthew
Date: 2015
Collection: Electronic Theses & Dissertations
Description: Streamside rearing facilities (SRFs) have been widely advocated in the Great Lakes basin as the preferred method of culturing Lake Sturgeon in situations where restoration goals to enhance or repatriate populations can be met by stocking. However, over the past decade, targeted stocking goals have been difficult to achieve due in large part to low survival and low growth during early life periods. This study examined three specific early life periods encountered during streamside operation ...
Show moreStreamside rearing facilities (SRFs) have been widely advocated in the Great Lakes basin as the preferred method of culturing Lake Sturgeon in situations where restoration goals to enhance or repatriate populations can be met by stocking. However, over the past decade, targeted stocking goals have been difficult to achieve due in large part to low survival and low growth during early life periods. This study examined three specific early life periods encountered during streamside operation (egg, free-embryo, and larval) and aimed to quantify the effects of different methodologies on the body size and survival of lake sturgeon in a SRF. Information collected during the egg period provides insight regarding the use of different egg chemotherapeutants, de-adhesion and incubation procedures, as well as the documentation of microbial community composition on lake sturgeon egg surfaces. Among egg chemotherapeutants utilized in streamside hatcheries, hydrogen peroxide showed higher mean proportional survival compared to formalin and the control (although results were not statistically significant). Additionally, chemotherapeutants may have selected for microbial communities that have been determined in other studies to be pathogenic. The effects of de-adhesion and incubation on lake sturgeon eggs were quantified using egg survival, egg oxygen consumption rate, and body size as response variables. Results revealed that these variables, except egg survival, did not vary significantly among de-adhesion and incubation treatments. Microbial community composition data suggest de-adhesion and incubation techniques affect the bacterial community composition on the egg surface which may provide insight into mechanisms responsible for differences detected in survival. At the free-embryo period, the effects of rearing density and family on body size and survival in association with dissolved oxygen concentration were quantified to the time of emergence. A significant density and family effect on free-embryo body size at emergence was documented. Feeding regimes, as well as the effects of different weekly prophylactic chemotherapeutants were quantified during the larval period. Results from feeding regime studies revealed significant differences in body size as a function of feeding frequency in hatchery-produced larvae to 30 days post-exogenous feeding. In addition, using hatchery-produced as well as wild-caught larvae, significant differences in body size and survival as a function of alternate food types were documented. Results from the weekly prophylactic chemotherapeutant study revealed a significant treatment effect on the survival of young-of-year lake sturgeon at 49 days post-exogenous feeding. This investigation at multiple life periods highlights methods that improve survival and growth, as well as serves as a tool for the development of standard operating procedures for SRFs geared to enhance current production and recovery of the Great Lakes Lake Sturgeon.
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Title: The role of UreD in nickel urease maturation and spectroscopic investigations into the iron urease
Creator: Farrugia, Mark Anthony
Date: 2015
Collection: Electronic Theses & Dissertations
Description: Urease catalyzes the hydrolysis of urea into ammonia and carbamic acid, with the latter compound decomposing into a second molecule of ammonia and carbonic acid. The enzyme from Klebsiella aerogenes is composed of three subunits (UreA, UreB, and UreG) and assembles into a trimer of heterotrimers (UreABC)3. The in vivo formation of its di-nickel, carbamylated lysine-bridged active site requires four accessory proteins: UreD, UreE, UreF, and UreG. The sequential binding of UreD, UreF, and UreG...
Show moreUrease catalyzes the hydrolysis of urea into ammonia and carbamic acid, with the latter compound decomposing into a second molecule of ammonia and carbonic acid. The enzyme from Klebsiella aerogenes is composed of three subunits (UreA, UreB, and UreG) and assembles into a trimer of heterotrimers (UreABC)3. The in vivo formation of its di-nickel, carbamylated lysine-bridged active site requires four accessory proteins: UreD, UreE, UreF, and UreG. The sequential binding of UreD, UreF, and UreG to urease or the binding of an accessory protein complex consisting of UreD:UreF:UreG primes the enzyme for activation by nickel that is delivered by UreE. Two of my projects focused on determining the role of UreD in this activation process and characterizing the properties of a soluble UreD:UreF:UreG accessory protein complex. I characterized a soluble, urease accessory protein complex containing a translational fusion of the maltose binding protein with UreD (MBP-UreD), UreF, and UreG (termed MBP-UreDFG) that was formed in vivo. This complex bound nickel weakly and existed as a dimer of heterotrimers in solution, with two UreF protomers located at the interfacial site. (MBP-UreDFG)2 dissociated to the heterotrimer as it bound to urease apoprotein or holoenzyme. The interaction with the apoprotein was disrupted by the presence of nickel and (UreG)2 dissociated from (MBP-UreDFG)2 in buffer containing GTP, magnesium, and nickel. I used mutagenesis approaches to examine the interaction of UreD with both urease and UreF and to explore the function of this protein in the transfer of nickel into the active site of urease. On the basis of a multiple sequence alighnment and a UreD homology model I generated from the Helicobacter pylori UreH:UreF:UreG crystal structure (UreH is homologous to UreD), 26 residues were selected for substitution. None of the variants were affected in their urease:UreD and UreD:UreF interactions in vivo. In vivo activation studies using UreD variants produced in the context of the complete urease gene cluster identified the D63A, D63Q, S85K, D142A, E176A, and E176Q UreD variants as being deficient in urease activation. The substituted residues mapped to a buried water tunnel identified in silico which originates at the putative UreF:UreD interface and exits at the opposite face of UreD. Purified urease activated in vivo by these variants contained substoichiometric amounts of nickel and varied amounts of zinc and iron per UreABC. My final project focused on characterization of the iron-containing urease from Helicobacter mustelae, UreA2B2, by resonance Raman spectroscopy. Previous studies showed the diferrous active site of this enzyme is rendered inactive in the presence of O2, yielding a μ-oxo bridged, diferric metallocenter. In contrast to earlier results, I observed downshifts of the νs and νas(Fe-O-Fe) following anaerobic reduction in H218O and subsequent chemical oxidation relative to analysis of enzyme in H216O, consistent with exchange of the μ-oxo atom. The νs(Fe-O-Fe) was downshifted by 10 cm-1 when the enzyme was incubated with urea or the slow-binding substrate phenyl phosphorodiamidate, but not following incubation with the inhibitor acetohydroxamic acid or the chaotropic agent guanidinium chloride. Rapid bulk-solvent exchange studies identified a urea- and solvent-sensitive mode at ~ 530 cm-1 which downshifted to ~511 cm-1 in D2O or H218O and upshifted by 10 cm-1 in the presence of urea. This result was consistent with a terminal Fe-OH stretch where the hydroxyl group is not displaced on substrate binding. I also identified a slow substrate-binding form of UreA2B2.
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Title: Suspected precursor-targeted immune-mediated anemia in dogs
Creator: Assumpção Lucidi, Cynthia de
Date: 2015
Collection: Electronic Theses & Dissertations
Description: ABSTRACTSUSPECTED PRECURSOR-TARGETED IMMUNE-MEDIATED ANEMIA IN DOGSByCynthia de Assumpção LucidiImmune-mediated hemolytic anemia (IMHA) results in regenerative anemia and is the most well studied immune-mediated anemia in dogs. However, the underlying cause of IMHA remains unknown, and mortality remains a problem. In a different condition, dogs with suspected precursor-targeted immune-mediated anemia (PIMA) present with nonregenerative anemia and ineffective erythropoiesis, which have...
Show moreABSTRACTSUSPECTED PRECURSOR-TARGETED IMMUNE-MEDIATED ANEMIA IN DOGSByCynthia de Assumpção LucidiImmune-mediated hemolytic anemia (IMHA) results in regenerative anemia and is the most well studied immune-mediated anemia in dogs. However, the underlying cause of IMHA remains unknown, and mortality remains a problem. In a different condition, dogs with suspected precursor-targeted immune-mediated anemia (PIMA) present with nonregenerative anemia and ineffective erythropoiesis, which have occasionally been associated with phagocytosis of erythroid precursors (rubriphagocytosis) or myelofibrosis. The pathogenesis of PIMA has not yet been determined, but roles for immunoglobulin and/or complement have been suspected. Additional involvement of apoptosis-like mechanisms with phosphatidylserine (PS) exposure is possible in both canine IMHA and PIMA based on previous studies in people and dogs. Our central hypothesis is that PIMA is part of a spectrum of immune-mediated anemias including IMHA, in which IgG, with or without the contribution of phosphatidylserine (PS), target and promote phagocytosis of different stages of erythroid cells, simultaneously or independently. The rationale was that better characterizing the pathogenesis of PIMA and its association with IMHA will ultimately help establish diagnostic criteria, identify appropriate therapeutic strategies based on knowledge of the pathogenesis of the diseases, and raise veterinary awareness of PIMA. This dissertation first describes a retrospective study of dogs with PIMA with the main goal of helping characterize canine PIMA and facilitate its recognition and diagnosis. Then it describes the development of flow cytometric assays for RBC and erythroid precursor IgG, including a Percoll gradient separation for erythroid populations. These methods were used for isolation of erythroid populations and their assessment for IgG and PS in IMHA and PIMA dogs, healthy dogs, and sick dogs with no evidence of IMHA or PIMA. We found that IMHA dogs had significantly higher IgG and PS when compared to healthy and non-IMHA dogs. Additionally, we showed that a subset of PIMA dogs had increased IgG-positive erythroid precursors when compared to healthy and non-IMHA dogs, and erythroid precursors from most tested PIMA dogs had more PS-positive erythroid precursors than healthy dogs; however, no sick dogs without PIMA were tested for comparison. These findings suggest a role for IgG in canine PIMA and for PS in canine IMHA and PIMA. Finally, we demonstrated the expression of DEA1.1 on canine erythroid precursors from rubriblasts through metarubricytes.
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