Life Sciences Commons^™

Use Of Thermal Microhabitats By Herpetofauna In A Fragmented Rainforest Landscape In Colombia, Catalina Valderrama

Masters Theses

No abstract provided.

Degradation And Vulnerability To Climate Change In High Andean Rangelands, Samuel Pizarro, Javier Ñaupari

IGC Proceedings (1997-2023)

Rangeland degradation is a process associated with loss of ecosystem equilibrium. Therefore, this work seeks to identify the most important factors that cause the degradation process of rangelands, assess the degree of degradation and vulnerability to current climate change of these ecosystems; and determine if there is a relationship between the degree of rangeland degradation and vulnerability to climate change in high Andean rangelands. The study was located in the central highlands of Peru (Ancash, Junín, Pasco, Huancavelica and Lima) and involved the design of a framework to assess rangeland degradation based on field information and Landsat satellite products that …

Caulobacter Clpxp Adaptor Popa’S Domain Interactions In The Adaptor Hierarchy Of Ctra Degradation, Thomas P. Scudder

Masters Theses

The degradation and recycling of protein is a process essential for the maintenance and regulation of cellular function. More specifically, in Caulobacter crescentus, the ClpXP protease is responsible for driving progression through the cell cycle and protein quality control. This protease utilizes three known adaptors to selectively degrade proteins that initiate different stages of development. This thesis will elaborate on the specific binding interface on one of these adaptors, PopA, with another, RcdA, and focus in on specific residues on PopA and investigate their roles in adaptor binding and delivery of CtrA, the master regulator of Caulobacter. Finally, I …

Tmem27 Suppresses Tumor Development By Promoting Ret Ubiquitination, Positioning, And Degradation, Qianjin Guo, Zi-Ming Cheng, Hector Gonzalez-Cantú, Matthew Rotondi, Gabriela Huelgas-Morales, Purushoth Ethiraj, Zhijun Qiu, Jonathan Lefkowitz, Wan Song, Bethany N Landry, Hector Lopez, Cynthia M Estrada-Zuniga, Shivi Goyal, Mohammad Aasif Khan, Timothy J Walker, Exing Wang, Faqian Li, Yanli Ding, Lois M Mulligan, Ricardo C T Aguiar, Patricia L M Dahia

Journal Articles

The TMEM127 gene encodes a transmembrane protein of poorly known function that is mutated in pheochromocytomas, neural crest-derived tumors of adrenomedullary cells. Here, we report that, at single-nucleus resolution, TMEM127-mutant tumors share precursor cells and transcription regulatory elements with pheochromocytomas carrying mutations of the tyrosine kinase receptor RET. Additionally, TMEM127-mutant pheochromocytomas, human cells, and mouse knockout models of TMEM127 accumulate RET and increase its signaling. TMEM127 contributes to RET cellular positioning, trafficking, and lysosome-mediated degradation. Mechanistically, TMEM127 binds to RET and recruits the NEDD4 E3 ubiquitin ligase for RET ubiquitination and degradation via TMEM127 C-terminal PxxY motifs. Lastly, increased cell …

Herders And Wetland Degradation In Northern Cameroon, E. Tedonkeng Pamo, F. Tendonkeng, J. R. Kana

IGC Proceedings (1997-2023)

Livestock rearing in Northern Cameroon is carried out under two majors systems: the nomadic and the transhumance production systems (Pamo & Pamo, 1991). Nomadism is the practice of wandering from place to place, while transhumance involves seasonal displacement of flocks from one area to another by herders. These production systems involved large grazing areas, which may encompass different ecosystems. The Yaére, the only wetland of the northern Cameroon, is the major dry season grazing lands for livestock and wildlife. The main characteristic of this wetland is that the whole area is excluded from grazing during the growing season as a …

Ensiling Characteristics And Ruminal Degradation Of Italian Ryegrass With Or Without Wilting And Added Cell Wall Degrading Enzymes, Z. Yu, Jianguo Han, Z. He, X. Qingfang, B. Chunsheng, N. Nishino

IGC Proceedings (1997-2023)

The previous experiment (Yu zhu et al.,1999) has shown that the efficacy of added enzymes varied greatly according to the DM content of the material crop. The silage DM did not alter the effects of enzymes on the in vitro digestion of NDF (Yu zhu et al.,1999, Yu zhu et al.,2000). The aim of this experiment was to study the effect of wilting and enzymes on fermentation quality, chemical composition and in situ digestion of Italian ryegrass (Lolium multiflorum Lam.) silage.

Reasons For The Premature Decline In Astragalus Adsurgens Stands In Kerqin Sandy Land, Qizhong Sun, Z. L. Wang, J. G. Han, Y. W. Wang, G. R. Liu

IGC Proceedings (1997-2023)

Diseases partly account for reductions in Astragalus adsurgens stand longevity. The effect of some cultural practices on the control of pests and diseases have been reported (Hou, 1986; Nan, 1996), but few reports have detailed the relationship among soil fertiliser status, diseases and premature stand decline. This study was conducted to investigate these relationships in order to extend the longevity of Astragalus adsurgens stands.

The Effect Of Fermentation Of Calliandra Calothyrsus, Gliricidia Sepium, Leucaena Leucocephala And Maize Forage On Rumen Degradation And Microbial Protein Synthesis, H. Kato, F. B. Bareeba, Elly N. Sabiiti, C. Ebong

IGC Proceedings (1997-2023)

Ensiling as a means of storing green fodder by acidification has a profound effect on the chemical composition of the resultant silage. Ensiling could therefore, ameliorate the effects of anti-nutritional factors associated with browses. The objective of the experiment was to determine fermentation characteristics and rumen degradation (D) of ensiled Calliandra calothyrsus (C), Gliricidia sepium (G), Leucaena leucocephala (L) and maize forage.

Extraction Of Challenging Forensic Samples Using The Microgem Dna Extraction Kit, Falyn R. Vega

Student Theses

In forensic science, DNA extraction can be a tedious and resource-intensive process. Extraction with Proteinase K is an industry standard but has its drawbacks, such as requiring multiple ionic detergents and washing steps. MicroGEM has developed a new enzyme called forensicGEM that is temperature-dependent and compatible with mesophilic enzymes, offering complete DNA extraction in about 20 minutes in a single tube, limiting contamination, loss of sample, and working time. ForensicGEM can extract DNA from highly degraded samples, potentially leading to more complete STR profiles. Highly degraded tissue and bone samples were collected and extracted with the forensicGEM …

Herders And Wetland Degradation In Northern Cameroon, E. Tedonkeng Pamo, F. Tendonkeng, J. R. Kana

IGC Proceedings (1997-2023)

Livestock rearing in Northern Cameroon is carried out under two majors systems: the nomadic and the transhumance production systems (Pamo & Pamo, 1991). Nomadism is the practice of wandering from place to place, while transhumance involves seasonal displacement of flocks from one area to another by herders. These production systems involved large grazing areas, which may encompass different ecosystems. The Yaére, the only wetland of the northern Cameroon, is the major dry season grazing lands for livestock and wildlife. The main characteristic of this wetland is that the whole area is excluded from grazing during the growing season as a …

Grazing Impacts On Rangeland Condition In Semi-Arid South-Western Africa, A. Rothauge, G. N. Smit, A. L. Abate

IGC Proceedings (1997-2023)

The savannah biome, consisting of a dense herbaceous layer and a relatively open woody layer in competitive balance, constitutes 64% of the land surface of Namibia, an arid country in south-western Africa, and is used mainly for extensive cattle and sheep ranching. About half of the savannah area is affected by dense to moderately dense bush-thickening, resulting in a ten-fold decrease in the rangeland’s grass-based carrying capacity and a concomitant loss in meat production of about US$115 million per year (De Klerk, 2004). Bushencroached areas typically have densities > 2 000 bushes/ha with > 90% belonging to a single species. High grazing …

Reasons For The Premature Decline In Astragalus Adsurgens Stands In Kerqin Sandy Land, Qizhong Sun, Z. L. Wang, J. G. Han, Y. W. Wang, G. R. Liu

IGC Proceedings (1997-2023)

Diseases partly account for reductions in Astragalus adsurgens stand longevity. The effect of some cultural practices on the control of pests and diseases have been reported (Hou, 1986; Nan, 1996), but few reports have detailed the relationship among soil fertiliser status, diseases and premature stand decline. This study was conducted to investigate these relationships in order to extend the longevity of Astragalus adsurgens stands.

Biological Remediation Of Fragipan, Corey Hale

Honors College Theses

The fragipan layer in the soil is a naturally occurring subsurface layer that restricts water percolation as well as inhibits root growth. A fragipan layer can be found almost ubiquitously across Southwestern Kentucky. This limits how agriculturalists manage soils in this area. It has been recently discovered by the University of Kentucky that Annual Ryegrass roots produce 3,4 dihydroxyphenylpropionic acid (DHPPA) that reacts with this hardpan to weaken the layer. Certain bacteria, such as Escherichia coli, Lactobacilli, and Bifidobacteria can also synthesize DHPPA through a breakdown process of chlorogenic acid. This reaction typically happens in the human digestive tract. …

Reasons For The Premature Decline In Astragalus Adsurgens Stands In Kerqin Sandy Land, Q. Zh. Sun, Z. L. Wang, J. G. Han, Y. W. Wang, G. R. Liu

IGC Proceedings (1997-2023)

Diseases partly account for reductions in Astragalus adsurgens, stand longevity. The effect of some cultural practices on the control of pests and diseases have been reported (Hou, 1986; Nan, 1996), but few reports have detailed the relationship among soil fertiliser status, diseases and premature stand decline. This study was conducted to investigate these relationships in order to extend the longevity of Astragalus adsurgens stands.

Principles Of Aaa+ Proteases, Samar Mahmoud

Doctoral Dissertations

ATPases associated with diverse cellular activities (AAA+) proteases in bacteria help maintain protein homeostasis by degrading misfolded and regulatory proteins. While a handful of protein targets for these proteases have been identified in Caulobacter crescentus and other organisms, more research is needed to elucidate mechanisms that govern substrate specificity. In the second chapter of this thesis, I will elaborate on how AAA+ substrate specificity is less rigid than previous work has suggested and how limiting ATP or mutations can alter substrate preferences of the ClpXP protease. In the third chapter, I will highlight our efforts to use a quantitative proteomics …

Characterizing The Multifaceted Roles Of The Proteasomal Deubiquitinase Uch37 In Proteostasis, Heather A. Bisbee

Doctoral Dissertations

Cellular protein pools are maintained through the biological processes of synthesis, degradation and quality control. As the dysregulation of these processes has been implicated in diseases such as neurodegeneration and cancer, understanding their functions is critical for drug development. Modification of proteins with ubiquitin may direct them to the proteasome, a large cellular protease complex, for degradation. Yet, the proteasome contains three deubiquitinating enzymes (DUBs) which remove ubiquitin from proteins, potentially altering their fate. As each DUB recognizes specific ubiquitin linkages and architectures, their activity may regulate how the proteasome handles substrates in dynamic cellular contexts. In this work, we …

Degradation Of Organic Pollutants Using A Photo-Enzymatic Cascade Process, Yu Xiao-Min, Pan Dai-Qing, Long Qing-Yun, Chen Xiao-Yang

Food and Machinery

Objective:A strategy of degrading organic pollutants using a photo-enzymatic cascade process was established, to avoid the problem caused by the use of H2O2 as oxidant in peroxidase-catalyzed reaction.Methods:After screening of photosensitizer, reaction pH and temperature, phenols and azo dyes can be degraded efficiently herein, by a combination of photo-catalytic H2O2 generation in situ and peroxidase-catalyzed oxidation.Results: 8 organic pollutions in different structure can be degraded with good to excellent degradation rate within 40 minutes. Moreover, the mechanism of this degradation process was proposed.Conclusion: Compared with classic methods of degrading organic pollutants, this photo-enzymatic cascade process …

Intensification Of Pastoralism As A Driver Of Degradation In The Algerian Steppe, S. Bencherif, P. Manzano

IGC Proceedings (1997-2023)

Land degradation linked to pastoralism use has been a worldwide concern for decades. A biological approach has often been use to understand such phenomena, usually disregarding economic and social factors. Radical transformations of pastoralism at the Algerian steppe constitute a good case study to provide an integrated understanding and to better orient development in other pastoralist areas across the world. Different actions by the public sector since the 1960s, as well as the land legislation adopted and the strong agricultural subventions during 2000-2010, have favored a massive conversion of land and resource management. This translates into conversion of many pastures …

Transformation Of Major Peanut (Arachis Hypogaea) Stilbenoid Phytoalexins Caused By Selected Microorganisms, Victor S. Sobolev, Travis E. Walk, Renee S. Arias, Alicia N. Massa, Valerie A. Orner, Marshall C. Lamb

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The peanut plant accumulates defensive stilbenoid phytoalexins in response to the presence of soil fungi, which in turn produce phytoalexin-detoxifying enzymes for successfully invading the plant host. Aspergillus spp. are opportunistic pathogens that invade peanut seeds; most common fungal species often produce highly carcinogenic aflatoxins. The purpose of the present research was to evaluate the in vitro dynamics of peanut phytoalexin transformation/detoxification by important fungal species. This work revealed that in feeding experiments, Aspergillus spp. from section Flavi were capable of degrading the major peanut phytoalexin, arachidin-3, into its hydroxylated homolog, arachidin-1, and a benzenoid, SB-1. However, Aspergillus niger from …

Arkansas Bulletin Of Water Research - Issue 2021-2022, Erin Grantz, Lillie Haddock, Brian E. Haggard

Arkansas Bulletin of Water Research

The Arkansas Bulletin of Water Research (Bulletin) is a publication of the Arkansas Water Resources Center (AWRC). We publish the Bulletin to communicate the major findings of research funded by the Water Resources Research Act Section 104(b) in Arkansas. This research is relevant to Arkansas water stakeholders, and the Bulletin provides an easily searchable and aesthetically engaging access option.

This is the fourth publication of the Bulletin. This issue contains final reports from research projects that were funded by the 104(b) program in fiscal years 2019 and 2020. The articles in this issue can be cited as an AWRC publication. …

An Investigation Into The Mechanism Of Proteasome Dysfunction In Neurodegenerative Disease And The Biological Impact Of Proteasome Hyperactivation In C. Elegans, Raymond T. Anderson

Graduate Theses, Dissertations, and Problem Reports

Aging is an inevitable process that occurs as humans grow older. It is characterized by the chronological accumulation of cellular damage over time leading to functional decline as an organism grows older. Several processes are thought to contribute to the aging phenomenon, but one of the most prolific of these is the disruption of protein homeostasis (proteostasis). The collapse of proteostasis can lead to accelerated aging and the development of age-related diseases including devastating neurodegenerative diseases (NDs) like Alzheimer and Parkinson disease. Virtually all NDs are characterized by the buildup of proteins in and around neurons resulting in neuronal death …

Evaluation Of A Number Of Grass Species For Restoring Degraded Semi-Arid Rangelands In Southern Africa, K. Kellner, S. De Wet

IGC Proceedings (1997-2023)

The biophysical environment is an important determinant of land degradation in both commercial and communal land tenure systems in South Africa. According to a recent study on the status of land degradation, approximately 25% of the total land cover in South Africa is degraded. Several technologies exist to restore the soil and vegetation degraded areas in natural pastures. To improve the production and biodiversity potential for agricultural and conservation uses in these rangelands, a common restoration technology includes the cultivation the eroded and compacted soil surfaces by rip- ploughing and the re-vegetation with high productive, palatable and perennial species. Five …

Water-Use Efficiency And Infiltration Under Different Rangeland Conditions And Cultivation In A Semi-Arid Climate Of South Africa, Hennie A. Snyman

IGC Proceedings (1997-2023)

The objective of this study was to determine the impact of rangeland in different botanical composition classes (good, moderate and poor), on water-use efficiency (WUE: crude protein produced per unit of evapotranspiration) and soilwater content. The same measurements were also made on an undisturbed bare soil surface and soil cultivated twice per annum. Evapotranspiration was determined by quantifying the soil-water balance equation with the aid of runoff plots and soil-water content measurements done by a neutron hydroprobe. Water-use efficiency declined significantly (P ≤ 0.01) with rangeland degradation. Rangeland in good condition averaged a WUE of 0.28 kg crude protein ha …

In-Vivo Evaluation Of Molybdenum As Bioabsorbable Stent Candidate, Malgorzata Sikora-Jasinska, Lea M. Morath, Maria P. Kwesiga, Margaret E. Plank, Alexia L. Nelson, Alexander A. Oliver, Martin L. Bocks, Roger J. Guillory Ii, Jeremy Goldman

Peer Reviewed Articles

Biodegradable stents have tremendous theoretical potential as an alternative to bare metal stents and drugeluting stents for the treatment of obstructive coronary artery disease. Any bioresorbable or biodegradable scaffold material needs to possess optimal mechanical properties and uniform degradation behavior that avoids local and systemic toxicity. Recently, molybdenum (Mo) has been investigated as a potential novel biodegradable material for this purpose. With its proven moderate degradation rate and excellent mechanical properties, Mo may represent an ideal source material for clinical cardiac and vascular applications. The present study was performed to evaluate the mechanical performance of metallic Mo in vitro and …

Mechanistic Insights Into Diverse Protease Adaptor Functions, Nathan J. Kuhlmann

Doctoral Dissertations

Protein degradation is an essential cellular process that helps maintain proper homeostasis. The ClpXP protease broadly regulates bacterial development and quality control during the cell cycle. The range and order of substrates that ClpXP degrades during the cell cycle is dictated by 3 accessory proteins, which are known as adaptors. This thesis will elaborate on how dimerization tightly regulates the stability and activity of the adaptor protein at the center of this hierarchy, RcdA, and show how this affects normal cellular processes in Caulobacter crescentus. I will discuss the mechanism by which dimerization limits RcdA activity and how the dimerization …

Use Of Remote Sensing To Guide The Assessment Of Temperate Grassland Degradation In The Territory, M. Martinez

IGC Proceedings (1997-2023)

The methodology Participatory Rangeland and Grassland Assessment (PRAGA), in its baseline phase, more specifically in stage 4, suggests remote sensing to assess at landscape scale. In order to determine the sites to be evaluated, grassland pixels of the Modis sensor were taken into account. Within it, three types of soils were differentiated: superficial, medium and deep, according to the previous existing cartography (2).

Within each soil type, pixels with significant trends (ἀ < 0.05), positive and negative (bright and hot), for the period 2000 -2017, were searched for both, IPSE and RESTREND. Therefore, 6 pixels of the Modis sensor were selected for each landscape.

From the field evaluation it appears that the greatest difference between the bright and hot trends was the height of the forage, and that both are pasture conditions …

Variations, Validations, Degradations, And Noninvasive Determination Of Pregnancy Using Fecal Steroid Metabolites In Free-Ranging Pronghorn, Cole A. Bleke, Eric M. Gese, Susannah S. French

USDA Wildlife Services: Staff Publications

Pregnancy status is a key parameter used to assess reproductive performance of a species as it represents a starting point for measuring vital rates. Vital rates allow managers to determine trends in populations such as neonate survival and recruitment; two important factors in ungulate population growth rates. Techniques to determine pregnancy have generally involved capture and restraint of the animal to obtain blood samples for determining serum hormone levels. Non-invasive pregnancy assessment, via feces, eliminates any hazards between handler and animal, as well as removes handling-induced physiological biases. Using noninvasive fecal sampling, we conducted hormone validations, investigated pregnancy rates, and …

Research Of The Efficiency Of The Solar Battery Operations In Real Exploitation Conditions, Umarbay Omanovich Odamov, Mirziyo Mirkamilovich Kamilov, Shavki Kulaganovich Niyazov, Kihyun Song

Scientific reports of Bukhara State University

Introduction. Nowadays, there is a constant growth of the demand for the use of solar power plants and obtaining green energy. In the using process of them in real conditions, a decrease in efficiency is observed. Because of the influence of external and internal factors on solar cells, the Coefficient of Efficiency(COE) panels decreases. The study of these influencing factors today is one of the actual problems. In this work is presented a study of the efficiency of a solar battery in real operating conditions. Research methods. By using an electronic counter DTS-541U№530230, the output parameters of solar cells were …

Community‐Based Management Is The Basic Way To Realize Sustainable Use And Achieve Environmental Protection For Grasslands On The Tibetan Plateau, Guozhen Du, Jianjun Cao

IGC Proceedings (1997-2023)

No abstract provided.

Assessing And Mapping The Spatial-Temporal Change In Forest Phenology Of Arabuko-Sokoke Forest Using Moderate Resolution Satellite, Bailey Ytterdahl

Independent Study Project (ISP) Collection

This study focuses on coastal forests in Kenya that have some of the highest variety of flora and fauna, specifically Arabuko Sokoke Forest. Arabuko Sokoke Forest is located 110 miles north of Mombasa and 18 kilometers south of Malindi. This forest is known to be a worldwide biodiversity hotspot that is home to endemic and rare plants and animals. Within the Arabuko Sokoke Forest ecosystem, there are two main issues that challenge the conservation of the area. First, there has been more competition for land, primarily for agriculture and development. Second, there is an increase demand for forest resources due …