Digital Commons Network^™

Nadh-Bound Aif Activates The Mitochondrial Chchd4/Mia40 Chaperone By A Substrate-Mimicry Mechanism, Chris A Brosey, Runze Shen, John A Tainer

Faculty, Staff and Student Publications

Mitochondrial metabolism requires the chaperoned import of disulfide-stabilized proteins via CHCHD4/MIA40 and its enigmatic interaction with oxidoreductase Apoptosis-inducing factor (AIF). By crystallizing human CHCHD4's AIF-interaction domain with an activated AIF dimer, we uncover how NADH allosterically configures AIF to anchor CHCHD4's β-hairpin and histidine-helix motifs to the inner mitochondrial membrane. The structure further reveals a similarity between the AIF-interaction domain and recognition sequences of CHCHD4 substrates. NMR and X-ray scattering (SAXS) solution measurements, mutational analyses, and biochemistry show that the substrate-mimicking AIF-interaction domain shields CHCHD4's redox-sensitive active site. Disrupting this shield critically activates CHCHD4 substrate affinity and chaperone activity. Regulatory-domain …

The Alphaproteobacterial General Stress Response: Investigating Protein Structure, Dynamics, And Regulatory Mechanisms, Danielle Swingle

Dissertations, Theses, and Capstone Projects

Bacteria are relatively simple organisms that face a wide variety of environmental challenges. Their survival is determined by their ability to sense and respond to changes in their surroundings. Alphaproteobacteria commonly accomplish this using the general stress response (GSR). During the first step in this system, a signal is detected by a sensor histidine kinase (HK), modulating autophosphorylation within its kinase domain. HKs involved in the GSR generally belong to the HWE/HisKA2 family, a lesser studied group of HKs with noncanonical features. The signal is propagated when the HK phosphorylates the next protein in the pathway, PhyR. Once activated, PhyR …

The Role Of Secondary And Tertiary Structure In The Cap-Independent Translation Of Fgf-9 And Hif-1-Alpha, Amanda Michelle Whittaker

Dissertations, Theses, and Capstone Projects

Under normoxic conditions, eukaryotes initiate translation of RNA through eIF4E recognition of the 5’ cap. However, under cellular stress, eukaryotic translation must be initiated through a 4E-independent, or “cap-independent” mechanism, involving eukaryotic initiation factor 4G (eIF4G) binding directly to the 5’ untranslated regions (5’ UTR) of the RNA. eIF4G binding then recruits the ribosome to the transcript. While this mechanism is useful for translation of apoptotic transcripts and transcripts involved in cell survival, cap-independent translation is also utilized by oncogenic RNA for tumorigenesis. Previous work by our lab and others has categorized this recruitment and initiation mechanism as either internal-ribosome-entry-site …

Constructing A Parameterized Stimuli Space Suitable To Induce Controlled Changes In Human And Machine Perceptual Systems, Andrew Frankel

Dissertations, Theses, and Capstone Projects

Traditional computer vision applications focus on objective tasks, such as object detection, classification, or segmentation. Much of human experience is inherently subjective, such as our personal response to artwork. Individualized experiences are challenging to replicate in a controlled laboratory environment, as those experiences depend on the unique history and internal models of the observer. This work presents a technique to construct a 2-dimensional parameterized stimuli space suitable to induce controlled changes in the perceptual systems of both human and machine observers. Our contributions are threefold:

1. Using a balanced dataset of 8,800 fine art images spanning 11 art movements and 88 …

   ---

   Go to article

The Psychophysiology Of Primary And Secondary Variants Of Psychopathic Traits In Youth, Ines Guariguata

Dissertations, Theses, and Capstone Projects

Psychopathy is a cluster of personality traits marked by a pervasive callousness, lack of shame or remorse, deceitfulness, a persona of confidence and charm, shallow emotional connection, general lack of insight into their actions, and an absence of anxiety (Glenn & Raine, 2014; Hare, 2003). Research suggests that there are distinct etiological pathways to the development of psychopathic traits and that their responses to treatment are different (Craig et al., 2021; Yildrim & Derksen, 2015; Fleming et al., 2023). Primary variants show a low-fear, low-anxiety profile during stress, and have a genetic basis (Craig et al., 2021; Yildrim & Derksen, …

Tracing The Sources Of Nitrogen In Submarine Groundwater Discharge And Primary Producers In The Great South Bay Estuary, Nia H. Rene

Dissertations, Theses, and Capstone Projects

The primary aim of this research was to elucidate the impact of submarine groundwater discharge (SGD) and septic effluent on coastal primary producers in the Great South Bay (GSB). The study focused on three main objectives: assessing the impact of precipitation patterns on SGD, tracing nitrogen sources into the GSB, and determining the impact of these nitrogen sources on coastal primary producers. The research revealed that current precipitation patterns significantly influence SGD across different seasons, highlighting the seasonal variability in groundwater discharge and its implications for nutrient loading in coastal waters. A suite of tracers was employed to identify and …

Recurrent Selection For Partial Resistance To Anthracnose Disease In Shrubby Stylo (Stylosanthes Scabra), D F. Cameron, R A. Boland, S Chakraborty, B Jamieson, J.A G. Irwin

IGC Proceedings (1977-2023)

Three cycles of crossing have been completed in a recurrent selection programme for partial resistance to anthracnose disease of shrubby stylo (Stylosanthes scabra) In a field study of a subset of 40 F2 populations from the first cycle, highly significant differences (P<0.001) in anthracnose resistance were found for both male and female effects and for the female x male interaction, In a subsequent F3 progeny test of 99 families selected for disease resistance and yield, 92 of the families were resistant to highly resistant with leaf damage <1% (cf, >50% damage for the susceptible cultivar, Fitzroy). Strong discrimination for resistance was also obtained in a second subset of 23 F2 populations using combined glasshouse and field selection for resistance. Further improvement in anthracnose resistance was achieved in the second and third cycles of recurrent selection. The broadly based resistance of selections from the third cycle …

Calliandra Calothyrsus - A Potential New Shrub Legume For Tropical Animal Production?, B Palmer, R A. Bray, T M. Ibrahim

IGC Proceedings (1977-2023)

Calliandra calothyrsus outyielded leucaena in cutting experiments at 2 sites in northern Australia and I in Indonesia. Drying significantly depressed the voluntary intake and digestibility of leaf, possibly due to the presence of tannin. Calliandra has the potential as a supplement for the low quality grass common to the tropics both ln grazing and cut-and-carry systems.

Glycine Latifolia- A Potentially Useful Native Legume For Clay Soils In Tropical And Subtropical Australia, M C. Rees, R M. Jones, A.H D. Brown, J N. Coote

IGC Proceedings (1977-2023)

In tropical and subtropical Australia, more than 5 million ha of heavy-textured soils receive adequate rainfall for cropping or pasture improvement. Glycine latifolla, a perennial legume native to these areas, shows promise for permanent pastures or long term leys. It occurs from latitudes 22"8 to 31 •s on heavy textured soils in the 500-1200 mm rainfall zone. It is a prostrate plant that roots from stolons and sets seed under grazing, It is drought tolerant, frost resistant, and produces dry matter yields comparable to those from the introduced legumes Desmanthus virgatus and Indigofera schimperi, There is a need to …

Development Of Rhizoma Peanut For Forage In Lower South, Usa, Gordon M. Prine, Edwin C. French

IGC Proceedings (1977-2023)

Rhizoma (perennial) peanut (Arachiis glabrata Benth.) (RP) is n perennial, warm-season legume, adapted to well-drained soils of humid tropics and subtropics. It is grown in Florida and warmer portions of the south-eastern USA up to about 32°N. Cultivar Florigraze was released in 1978 and cv. Arbrook in 1986. Commercial hectarage of RP has increased about 40% annually to approximately 2000 ha in 1992. Propagated vegetatively from rhizomes, RP Is slow to establish. Rhizoma peanut is drought-tolerant, persistent, grows well on droughty, low-fertility soils, requires moderate to excessive soil drainage and requires no N and usually no P fertiliser. It …

Effects Of Cutting Heights And Cutting Frequencies On The Annual Yield Of Leucaena And Calliandra Hedges, O Ncamihigo, P Brandelard

IGC Proceedings (1977-2023)

A 3-year study was conducted in Burundi to examine the effects of 3 cutting heights (0, 50 and 100 cm) and 3 cutting frequencies (3, 4 and 6 months) on the total annual biomass yield and leaf production of 3 shrub legumes, Leucaena diverslfolia cv, Buitenzorg, L. leucocephala cv, Peruvian and Calliandra calothyrsus. Highest annual biomass and leaf production were obtained at the 100 cm cutting hejght, There was no significant effect of cutting interval on L. leucocephala but for Calliandra calothyrsus, leaf production was highest at the 4- month cutting frequency. Both biomass production and leaf production …

Performance Of Desmanthus Virgatus Accessions In The Caribbean, M B. Adjei, K Albrecht

IGC Proceedings (1977-2023)

Twenty-three Desmanthus virgatus accessions, established on a mildly alkaline clay soil (Typic Rendoll Mollisol), were repeatedly harvested to 10 cm stubble over a 2-year period whenever regrowths reached the early-pod stage of maturity to determine forage yield, leaf/stem proportions, forage quality and stand persistence. Differences were observed in seasonal growth distribution and annual forage yield of accessions. Collections from Venezeula and Mexico were among the most productive (8-11 t dry matter/ha/year) and from the Dominican Republic, the least productive (<6 t/ha/year) accessions. Most accessions perissted well under the lenient garvesting regime imposed. The proportion of leaf in dry forage ranged from 34 to 43% with average leaf crude protein (CP) content in vitro organic matter digestibility (IVOMD) of 19.2% and 83.4%, respectively. The average stem CP and IVOMD were 7.4% and 48.9%, respectively, and were not affected by accessions. Leaf samples of all Desmanthus accessions contained high levels of tannins (26-31 g tannic acid equivalent s/kg DM). However, unlike fibre fractions, leaf IVOMD was only weakly correlated with leaf tannin content (r-0.38).

Breeding For Rust Resistance In Marcoptilium Atropurpureum, R A. Bray

IGC Proceedings (1977-2023)

Rust in Macroptilium atropurpurewn cv. Siratro is an important disease, reducing both yield and quality, Resistance to the disease is conditioned by several genetic mechanisms, including single dominant. genes, multiple dominant genes, single major genes together with genes of lesser effect, and single recessive genes. Near-isogenic lines have been developed by backcrossing dominant genes into Slratro background, and these lines used to demonstrate pathogenic specialisation in Mexican collections of the rust organism. No variation In virulence is apparent in S Australian isolates of the fungus, Pour of the backcross populations, with resistance genes from geographically diverse origins, have been mixed …

Phenological Development Of Line 8400 Stylo And Alyeclover Planted At Two Dates In Subtropical Florida, M J. Williams, C G. Chambliss, J B. Brolmann

IGC Proceedings (1977-2023)

Line 8400 slylo (Stylosathes guianensis) remains vegetative later in the autumn than many tropical annual legumes. The objective of our study was lo determine the effect of planting dale (April or June) on the phenological development of Line 8400 stylo compared with alyceclover (Alysicarpus vaginalis). Root/shoot ratio of Line 8400 stylo (0.16) was not affected by planting date and was similar to April-planted alyceclover (0.15), but was lower (P<0.05) than June­planted alyceclover (0,21). Legume leaf/stem ratio was not affected by planting date, declined (P=0.0001) from an average of 2.79 at 4 weeks to 0.55 by 16 weeks post-planting, and was higher (P=0.03) for Line 8400 stylo (1.76) than alyceclover (1.29). Maximum dry mailer yield was 10.1 and 5.0 Mg/ha for April- and 7.2 and 5.6 Mg/ ha for June-planted Line 8400 stylo and alyceclover, respectively.

Selection Of Sylosanthes Spp. For The Cerrados Of Brazil, B Grof, A.T F. Fernandes, C D. Fernandez

IGC Proceedings (1977-2023)

Improved seed yield and leaf retention during the dry season coupled with anthracnose resistance were recorded among mid-season flowering progenies of intervarietal hybrids of Stylosantheses guianensis var. vulgaris x var. panciflora. Mineirao, a late-flowering accession of S. g11ia11e11sis var. vulgaris, displayed similar agronomic traits, but produced lower seed yields. Venezuelan accessions of S. capitata, and a binary mixture of S. capitata-S. ,nacrocepllala showed field resistance to anthracnose. Inter- and intraspecific variation for resistance to anthracnose disease was demonstrated by inoculation with virulent local and introduced pathotypes of Colletotrichum gloeosporioides. The development from these heterogeneous populations of cultivars …

Meeting The Challenge Of Adapting Leucaena Leucocephala To The Acid Oxisols And Utisolds Of South America And South-East Asia, E M. Hutton, Chin Peng Chen

IGC Proceedings (1977-2023)

Shtteen lines from 2 families of Leucaena leucocephala-L. diversifolia hybrids selected for acid-soil tolerance in Brazil were reselected in the Kuala Linggi acid-sulphate soil and Serdang oxisol in Malaysia. In the K. Linggi soil with 81 % Al saturation, highly acid-tolerant hybrids were selected with 35-79% more growth than the intolerant cv. Cunningham. At Serdang the oxisol had ·a mean 68% Al saturation and hybrids were selected with 19-49% more growth than Cunningham which lacked intolerance symptoms due to annual dolomite application. In a severe psyllid infestation at K. Linggi, 5 of the 14 hybrids from one family had …

Evaluation Of Wild Nut-Producing Arachis Species For Forage, A E. Kretschmer Jr, C E. Simpson, T C. Wilson, W D. Pitman

IGC Proceedings (1977-2023)

Fourteen nut-producing wild peanut (Arachis spp,) accessions were evaluated in single-plant plots and in ranchers' fields under grazing. Transplants were used for initial and some secondary planting, Agronomic characteristics and persistence were measured. The cv. Amarillo (4222) and a selection previously evaluated (2273) were used as controls. Plant yield, leaf and stem weights, nut production and other attributes varied among the accessions. Accession 2273 was one of the earliest and most prolific flowering and nut producers, while 4222 was the most persistent under initial grazing evaluation,

Production And Growth Characteristics Of Sixteen Gliricidia Provenances Grown In A Dryland Farming Are In Bali, W Puger, I M. Nitis, K Lana, M Suarna, W Sukanten

IGC Proceedings (1977-2023)

At evaluation of Gliricidia sepium provenances was conducted in Bali for 3 years on a calcareous-based red-brown Mediternn soil at a lowland site with 1000 mm annual rainfall. Fifteen provenances representing diverse geographical regions in Latin America were compared with an Indonesian provenance using a randomised block design. Plants were grown in alleys 4 m apart with plants spaced at 0.5 m apart within the alley. All the plants were cut at 150 cm height periodically, twice during the 4-month wet season and twice during the 8-month dry season. Significant differences were found between provenances for leaf and branch …

Advances In Forage Legumes: A Subsahara African Perspective, B H. Dzowela

IGC Proceedings (1977-2023)

In the context of diverse agricultural production systems in subSaharan Africa, advances made with forage legume research are outlined. The direction of research has been geared to evaluating and incorporating the forage legume technology in crop farming and pastoral livestock feeding systems, In systems with minimal fertiliser inputs; legumes have contributed to the crop phase by reducing the rate. of soil fertility decline, In pastoral systems legumes have contributed to rehabilitating the range and in improving the quality of grazing. In agropastoral systems legumes have conferred better quality and improved utilisation of crop residues, natural pastures and fallow lands. Major …

Advances In Research And Development With Sylosanthes And Other Tropical Pasture Legumes, D F. Cameron, C P. Miller, L A. Edye, J W. Miles

IGC Proceedings (1977-2023)

The last 20 years have seen major advances in research and development wilh tropical legumes. Research advances have been closely associated with substantial increases in the number and diversity of genetic resource collections, Release of a wide range of new cultivars has been based on selection for plant adaptation, persistence and productivity, screening for resistance to pest's and diseases, and the development of efficient seed production. Determination of fertiliser requirements and grazing management practices has resulted in sustainable animal production from legume-based pasture systems. Extensive pasture development has now occurred in both high and low input systems. Options vary from …

Integration Of Wildlife And Cattle On Communal Lands In Kangwane, South Africa, M Stalmans, A Van Wyk, M T. Mentis

IGC Proceedings (1977-2023)

The feasibility of integrating wildlife with the current livestock husbandry on communal lands in KaNgwane was investigated. Present stocking rates were 3 times the recommended figure for production farming. This fitted predictions based on the Jones-Sandland model for populations where the major consideration is maximum number of animals rather than high productivity. The integration of game was seen as a means to increase economic output, while spreading benefits from the use of natural resources to the community at large and establishing a form of ecologically sustainable land use. The active involvement of the community in the planning process and their …

Integrated Gamebird Farming As An Incentive To Promote Biodiversity And Conservation Of Rangelands, P J. Wiljoen, C R. Hurt

IGC Proceedings (1977-2023)

The popularity of gamebird hunting as a sport in Southern Africa serves as an incentive to rangeland owners to increase biodiversity on their properties. Gamebird utilisation is compatible with virtually all forms of land use, be it crop, domestic stock or wildlife production or a combination thereof, The range in habitat requirements, behaviour patterns and feeding niches of indigenous gameblrds ensures that at least one species is compatible with a specific agricultural practice, climate or vegetation type. Marginal and wasteland areas such as marsl}es, gullies, road verges and rocky outcrops, are prime gamebird production areas. The prospects of sport and …

Game Production On Private Land In South Africa, J C. Pauw, M J.S Peel

IGC Proceedings (1977-2023)

The game industry on private land in South Africa has grown considerably in the last 30 years, resulting in a greatly increased biodiversity on private rangeland. However, animals are not domesticated and management is difficult. Management becomes even more complex because commercial game production normally involves a number of species, including domestic stock, in the same production system. Mixed livestock-game ranching holds certain advantages for management and is generally perceived to be more profitable than either alone. Because of human preferences, a lack of clearly defined management objectives and lack of practical management recommendations, veld is generally heavily utilised and …

Determinants Of Herbaceous Species Composition On Wildlife Utilization Areas In The Eastern Transvaal Lowveld Of South Africa- A Preliminary Investigation, M.J S. Peel, G C. Stuart-Hill

IGC Proceedings (1977-2023)

This study investigated the. effect of recent past annual rainfall and stocking rate on herbaceous plant species composition in the Lowveld of the eastern Transvaal, South Africa. Annual rainfall and grazing (stocking rate) act synergistically in determining herbaceous species composition, annual rainfall exerting the greatest influence and grazing having a modifying effect particularly under extreme conditions. In mesic areas (mean annual rainfall of around 600 mm) a relatively favourable herbaceous composition was found under relatively higher grazer stocking rates of around 10 grazer units/JOO ha (10 GU/100 ha) In semi-arid areas (mean annual rainfall of around 400 mm) a lighter …

Cattle And Wildlife Ranching In The Zimbabwe Midlands: Are They Economically Compatible?, Urs P. Kreuter, John P. Workman

IGC Proceedings (1977-2023)

Thirty-five Midlands ranches earning revenue from beef caltle, wildlife, or both during 1989-90 were surveyed to determine their financial and economic· profitability. Market prices were used to calculate financial profit, and opportunity costs were used to estimate economic profit of each operation. Under current market conditions, only mixed ranches produced positive financial profits, Economic profits were significantly higher than financial profits for all three types of operation. This implies that they all faced production disincentives due to government policy interventions. However, there were no significant differences between the economic profits of the three types of operations and none of them …

Overcoming Limitations On The Productivity Of Browsing Ungulates In Africa, Norman Owen-Smith

IGC Proceedings (1977-2023)

In African savannas primary production by woody plants may match that by the grass layer. However, maximum population levels attained by browsing ruminants are only one tenth of those reached by similar sized grazers, The productivity of browsers is limited because (I) much foliage is out of reach, and dispersed by wind when shed; (2) most palatable trees are deciduous, leading to a food bottleneck during the late dry season; (3) leaves of many woody species are rendered unpalatable, indigestible or toxic by plant secondary metabolites. Management actions to overcome these limitations include (I) lopping trees to restrict their height; …

Southern United States Forest Range Management: History And Development, Henry A. Pearson

IGC Proceedings (1977-2023)

The history and development of forest range management in the southern USA are discussed, including influences of domestic livestock, wildlife, forestry, research, education and societies, Domestic cattle entered the USA in 1521; since then grazing the "piney woods" has been common. By the early 1930s, old growth timber was harvested from Texas to Florida and South Carolina. Fire control legislation helped reforestation to peak in 1959. This forced many cattlemen out of business owing to the fast-growing pines. Wildlife declined with colonisation but many populations were re­established after World War II. Public agencies, universities, and the Society for Range Management …

Economic And Ecological Features Of Livestock And Wildlife Utilization In Africa, J I. Barnes

IGC Proceedings (1977-2023)

This paper looks at livestock and wildlife utilisation in Africa within the framework of total economic value (TEV), which includes both utilisation and biodiversity values. In Africa, traditional use of wildlife involves open access systems on public land, Here, free ranging, public wildlife resources are used to produce subsistence or marketed meat and skins at smaII scale. Traditional livestock systems involve open access use of rangelands. Here, livestock are kept at small ·scale to produce draft power, milk, meat and as a store of .value. Commercial use of wildlife involves restricted access systems on both public and private lands. Here, …

Conservation Of Biodiveristy In Managed Rangelands, With Special Emphasis On The Ecological Effects Of Large Grazing Ungulates, Domestic And Wild, Patrick Duncan, Peter J. Jarman

IGC Proceedings (1977-2023)

Biodiversily with its different components (genes, species and ecosystems) is defined in relation to rangelands, whose Importance in its conservation is described. At the fine scale grasslands are much more diverse than tropical rain forest, and are comparably diverse at a regional scale, at least in Africa. Rangelands are crucially important world wide for 1he conservation of plants, and also for birds and large mammalian herbivores. Large ungulates (and other large herbivores) ace "keystone" species in these·ecosystems, playing a crucial role in the maintenance of diverse communities of plants, birds and invertebrates associated with such grasslands. Modification of the natural …

Major Beef Production Gains From Commercial Rain-Fed Leucaena-Grass Pastures In Central Queensland, Australia, J H. Wildin

IGC Proceedings (1977-2023)

Commercial leucnena-grass pastures in central Queensland increased from 24 ha in 1979 to about 20 000 ha in 1992. Since 1986 the exotic leucaena psyllid devastated leucaena (Leucaena leucocepliala) production along the humid coastal areas but not in the subcoastal plantings where the hot dry atmosphere controls the psyllid populations. The introduced rumen bacteria to detoxify DHP has enhanced the performance of cattle grazing leucaena. Unfertilised rain-fed leucaena-grass pastutes with leucaena rows 5-10 m apart have given annual steer live-weight gains of more than 250 kg consistently at stocking rates around 1-1.5 ha/steer. One cattleman with about 500 …