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Native Pasture Forage On Offer And Animal Response, G E. Maraschin, E L. Moojen, C.M D. Escosteguy, F L. Correa, E S. Apezteguia, L L. Boldrini, J Riboldi Jul 2024

Native Pasture Forage On Offer And Animal Response, G E. Maraschin, E L. Moojen, C.M D. Escosteguy, F L. Correa, E S. Apezteguia, L L. Boldrini, J Riboldi

IGC Proceedings (1977-2023)

The 5-yr. study on the native pasture of southern Brazil (30o S) under levels of dry matter on offer (DMO) and continuous stocking, with five tester steers plus the put-and-takers per pasture and two field replications, indicated dry matter residues as dependent on DMO. Dry matter (DM) yield increased with DM residues, as well as dead plant parts. Daily liveweight gains (DLG) and gain ha- 1 showed a curvilinear response to DMO and DM residues. Forage on offer levels promoting selective grazing enhance higher DLG and sustainable G. ha-1, and contributes to the well-being of the ecosystem.

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Pasture Species Effects On Animal Performance, T J. Fraser, S=J S. Rowarth, T L. Knight Jul 2024

Pasture Species Effects On Animal Performance, T J. Fraser, S=J S. Rowarth, T L. Knight

IGC Proceedings (1977-2023)

Increasing concerns about food quality have resulted in investigations into the effects of different forage species on animal production and carcass quality. Pure species plots of high-endophyte ryegrass (Lolium perenne L.), white clover (Trifolium repens L.), chicory (Cichorium intybus L.), plantain (Plantago lanceolata L.) or lotus (Lotus corniculatus L.) were established and lambs grazed the species for 120 days during summer. Pasture species influenced growth rate, hot carcass weight, GR, wool growth, faecal egg counts, adult nematodes at slaughter, and sheep meat odour and flavour. Lambs grazing white clover, lotus or chicory outperformed those grazing …

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Grazing Affects Pest And Beneficial Invertebrates In Australian Pastures, P J. Michael, M Grimm, M Hyder, P T. Doyle Jul 2024

Grazing Affects Pest And Beneficial Invertebrates In Australian Pastures, P J. Michael, M Grimm, M Hyder, P T. Doyle

IGC Proceedings (1977-2023)

Grazing annual subterranean pastures in Western Australia to targeted levels of pasture mass, instead of at a set stocking rate, affected numbers of invertebrates at the commencement of the following season. Treatments were controlled grazing to 1.4 t ha-1 or 2.8 t ha -1 dry weight of green pasture and set stocking at the average for the district. Grazing reduced numbers of redlegged earth mite, Halotydeus destructor, but increased numbers of lucerne flea, Sminthurus viridis. The most likely reason for the reverse effect on lucerne flea was the presence of an effective predator, the pasture snout mite, Bdellodes lapidaria …

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The Effect Of Stocking Rate On Herbage Utilization And Milk Production Under Time-Restricted Grazing By Lactating Dairy Cows, M Okubo, I Nonaka, K Furukawa, H Nakatsuji, S Kondo Jul 2024

The Effect Of Stocking Rate On Herbage Utilization And Milk Production Under Time-Restricted Grazing By Lactating Dairy Cows, M Okubo, I Nonaka, K Furukawa, H Nakatsuji, S Kondo

IGC Proceedings (1977-2023)

The effect of two stocking rates of 5 (L) and 7 (H) heads of lactating dairy cows per hectare on herbage utilization and milk production were determined under a time-restricted grazing during 2 years from 1993 to 1994. The annual herbage utilization and milk production from pasture in 1993 were lower in H than L (herbage, 7.9 vs. 9.1tDM/ ha; milk, 8.1 vs. 9.6t/ha) since the days of grazing cycle was considerably shorter in H than L (7.8 vs. 17.1days). As a result of changing the expected daily herbage intake per head of H seasonally in 1994, the annual herbage …

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The Relationship Of Grazing Conditions To Annual Changes Of Sward Characteristics And Herbage Utilization By Lactating Dairy Cows In The Snowy, Cold Region In Japan, H Nakatsuji, I Nonaka, S Kondo, M Okubo Jul 2024

The Relationship Of Grazing Conditions To Annual Changes Of Sward Characteristics And Herbage Utilization By Lactating Dairy Cows In The Snowy, Cold Region In Japan, H Nakatsuji, I Nonaka, S Kondo, M Okubo

IGC Proceedings (1977-2023)

In order to determine the relationship of grazing conditions to annual changes of sward characteristics and herbage utilization in the snowy, cold region in Japan, the data for pasture utilization of dairy cows under a time-restricted grazing on Experimental Farm, Hokkaido University, from 1984 to 1992 were used for analyses. An annual herbage utilization did not always decrease though legume crown coverage declined gradually with advancing years after swardestablishment. The annual herbage utilization (tDM/ha, Y) increased with increasing the stocking rate (cow-hr/ha, X) (Y=0.00136X-0.685, r=0.752**).

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Effect Of Grazing Pressure And Supplemental Level On Weight Gain In Dairy Heifers, J M. Mieres, Y M. Acosta Jul 2024

Effect Of Grazing Pressure And Supplemental Level On Weight Gain In Dairy Heifers, J M. Mieres, Y M. Acosta

IGC Proceedings (1977-2023)

An experiment designed to assess the effect of two grazing pressures (GP, expressed as kg MS/100 kg LW) and four levels of supplement (0, 0.25, 0.50 and 0.75 expressed as kg/100 kg LW) fed to yearling heifers (212 kg) on live weight gain, was carried out at the Dairy Unit of INIA La Estanzuela (Uruguay). The experiment consisted of 8 treatments. Forty animals were used in the experiment, 5 per treatment, each animal being a replication of the treatment. The animals were blocked by weight in 5 blocks of 8 animals each, and then randomly assigned to the different treatments. …

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Leaf Appearance Rate Of Native And Introduced Grasses Under Different Intensities Of Continuous Grazing (Argentina), M G. Agnusdei, A Mazzanti, J Cordero, M H. Wade Jul 2024

Leaf Appearance Rate Of Native And Introduced Grasses Under Different Intensities Of Continuous Grazing (Argentina), M G. Agnusdei, A Mazzanti, J Cordero, M H. Wade

IGC Proceedings (1977-2023)

Results of two grazing experiments on the effect of maintaining contrasting sward states upon leaf appearance rate of individual tillers (LAR) and tiller density (D) are reported. The following species were evaluated: Cynodon dactylon(Cd), Leersia hexandra(Lh), y Paspalum dilatatum(Pd) in a natural grassland of the Flooding Pampa, and Festuca arundinacea in a sown pasture. Except for Pd, LAR decreased with the increment of sward surface height. The degree of this morphogenetic plasticity varied among species. Implications for the stability of grass populations under continuous grazing are suggested; the effect of sward state upon LAR may represent one alternative way …

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Grazing Systems Research In The Falkland Islands, J A. Kerr Jul 2024

Grazing Systems Research In The Falkland Islands, J A. Kerr

IGC Proceedings (1977-2023)

Conceptual models of both the metabolisable energy (ME) balance of sheep in relation to the environment and the effects heavy grazing on vegetation and soils will form the basis for the development of a sustainable grazing system for wool production in the Falkland Islands. Research which integrates plant community ecology, agricultural meteorology, sheep energetics, grazing systems and socio-economics is described.

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Wool Production From Annual Pastures Intensively Grazed By Wethers In Southern Western Australia, M W. Hyder, A N. Thompson, P T. Doyle, M Grimm, P J. Michael Jul 2024

Wool Production From Annual Pastures Intensively Grazed By Wethers In Southern Western Australia, M W. Hyder, A N. Thompson, P T. Doyle, M Grimm, P J. Michael

IGC Proceedings (1977-2023)

Intensively grazing annual pastures in southern Western Australia to target amounts of feed on offer increased the greasy wool production per hectare three-fold or more compared to production from a setstocked grazing regime. Feed on offer was maintained at 0.8, 1.1, 1.4, 2.0, 2.8 t DM/ha during spring and wool growth per hectare compared to that of sheep set-stocked at the district average of 8 sheep/ha. The role of intensive grazing as a tactic to increase production and profitability of wool producers in Mediterranean environments is discussed.

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Utilized Metabolizable Energy And Its Impacts On The Management Of Grass Pastures In The Central Chaco Of Paraguay, D Stosiek, A Glatzle, R Schultze-Kraft Jul 2024

Utilized Metabolizable Energy And Its Impacts On The Management Of Grass Pastures In The Central Chaco Of Paraguay, D Stosiek, A Glatzle, R Schultze-Kraft

IGC Proceedings (1977-2023)

Animal production from sown pastures of Gatton Panic (Panicum maximum Jacq.) and Estrella (Cynodon nlemfuënsis Vand.) on a luvic Kastanozem in the Central Chaco of Paraguay (mean annual rainfall 850 mm) was measured over two years (Sep. 1992 to Nov. 1994). The pastures were grazed continuously by Brahman X Hereford steers at six stocking densities, ranging from 0.5 to 2.0 American Animal Units (1 AU = 454 kg) per hectare. Herbage availability, chemical composition (ME, XP, fibre) and cattle liveweight gains were measured at four weekly intervals. Building regression models for Utilized metabolizable energy (UME in GJ/ha) and …

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Milk Production From Ruzi Grass Alone, Ruzi Mixed With Leucaena And Ruzi Supplemented With Dolichos Lablab, S Tudsri, S Prasanpanich, S Swasdiphanich Jul 2024

Milk Production From Ruzi Grass Alone, Ruzi Mixed With Leucaena And Ruzi Supplemented With Dolichos Lablab, S Tudsri, S Prasanpanich, S Swasdiphanich

IGC Proceedings (1977-2023)

Three groups of dairy cattle were compared under different grazing managements viz. strip-grazed on pure ruzi grass (Brachiaria ruziziensis), strip-grazed on mixed pasture between ruzi and leucaena (Luecaena luecocephala) and strip-grazed on pure ruzi and supplemented with lablab (Lablab purpureus). The results showed that the animals that received the legumes through supplementary or mixed with the grass produced higher in daily milk yield (13.63 and 13.26 kg/cow) and fat percentage (4.7 and 4.5) than that of the pure grass alone (12.00 kg/cow for milk yield and 4.2 % for fat). This advantage was due …

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Zea Mays Grazing In Cattle Production Systems, V Mundy, B E. Anderson, T L. Gompert, T L. Mader, C A. Shapiro Jul 2024

Zea Mays Grazing In Cattle Production Systems, V Mundy, B E. Anderson, T L. Gompert, T L. Mader, C A. Shapiro

IGC Proceedings (1977-2023)

Nebraska producers have used silage maize (Zea mays L.) hybrids as a grazed forage in dairy and beef production systems. In an onfarm case study, farmers and researchers collaborated to gather information on production practices, grazing management, and plant characteristics of grazing maize within three forage-based dairy and beef systems. Production practices were generally similar to conventional grain corn production, except that in one system maize was seeded directly into a suppressed grass sod. Milk production from grazing maize was 23 kg/day/animal, compared to 24 kg/day/ animal before using maize and 22 kg/day/animal after using maize. Average gain of …

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Grazing Management Of Lotus In Eastern Australia: A Participatory Approach, M J. Blumenthal, J F. Ayers, Z Hochman Jul 2024

Grazing Management Of Lotus In Eastern Australia: A Participatory Approach, M J. Blumenthal, J F. Ayers, Z Hochman

IGC Proceedings (1977-2023)

Both Lotus uliginosus Schkukr and L. corniculatus L. require lenient grazing management for persistent production. However, grazing systems, where Lotus is adapted in eastern Australia are based on intermittent set stocking. Conflict between plant ecophysiology and the adverse influences of traditional grazing systems that limit the adoption of new grazing management technology have been addressed by a participatory (co-learning) research and development process. The approach taken involved the use of a facilitator who ran an initial meeting to involve stakeholders and subsequently established “colearning” groups and “co-learning” experimental sites. These sites are monitored, progress is reviewed, and knowledge is …

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Rhizobium Specificity In Leucaena, B F. Mullen, V E. Frank, R A. Date Jul 2024

Rhizobium Specificity In Leucaena, B F. Mullen, V E. Frank, R A. Date

IGC Proceedings (1977-2023)

Twenty-seven accessions of Leucaena, representing 20 species, were assessed for effective N-fixing symbioses in association with 13 strains of Rhizobium in N-free conditions in a glasshouse. Fifteen accessions formed effective symbioses with most strains of Rhizobium. Only 4 accessions required specific strains. Conversely, 9 of the strains of Rhizobium formed effective symbioses with most accessions of Leucaena. Only one strain was ineffective. Strains CB3060 and CB3126 were effective with 21 and 22 accessions of Leucaena, respectively.

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Agronomic Performance Of 118 Leucaena Accessions In The Subtropical Environment Of Southeast Queensland, Australia, B F. Mullen, H M. Shelton Jul 2024

Agronomic Performance Of 118 Leucaena Accessions In The Subtropical Environment Of Southeast Queensland, Australia, B F. Mullen, H M. Shelton

IGC Proceedings (1977-2023)

The DM productivity in contrasting environments of 118 Leucaena accessions was evaluated in sub-tropical Australia over a 2 year period. Harvests were timed to coincide with hot/wet and cool/dry seasons and data were analysed to compare growth in these environments. Eleven accession groups were identified by cluster analysis. Group 1, which contained F1 and F4 interspecific hybrids, were highly productive in all environments. Growth of L. leucocephala accessions was severely checked by psyllids in hot/ wet environments. Four groups comprising 60 accessions were unproductive in all environments. Identification of specific adaptation to cold temperature within groups in psyllid susceptible accessions …

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The Effects Of Storage Period On The Germinability Of Rhodes Grass (Chloris Gayana), K C. Kawonga Jul 2024

The Effects Of Storage Period On The Germinability Of Rhodes Grass (Chloris Gayana), K C. Kawonga

IGC Proceedings (1977-2023)

An experiment was initiated to investigate the post harvest changes in the seed quality of Rhodes grass (Chloris gayana). The aim of the study was to find out the causes of poor germination of locally produced Rhodes grass seed. Random samples (72) were taken from a seed lot grown at Golden Valley Research Station. Seventy-two random samples were subdivided into groups of twelve and were stored at six locations. Half the samples were stored at room temperature and the other half were stored in the refrigerator for a period of one to six months. The germination test was …

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Technology Development Of Pasture Seed Production For Small Scale Farmers In Uganda, P Lusembo, E N. Sabiiti, C Ebong Jul 2024

Technology Development Of Pasture Seed Production For Small Scale Farmers In Uganda, P Lusembo, E N. Sabiiti, C Ebong

IGC Proceedings (1977-2023)

Pasture seed production by smallholder farmers in Uganda is hardly developed. The stages of development since the early 1960s are described as initial forage evaluation for adaptability and productivity of various species, seed production trials in relation to plant population, fertilizer requirements and the use of support systems for climbing forage legumes. Annual seed production by smallholder farmers, under an informal seed production system, is reported to have risen from 1,200kg in 1989 to over 35 metric tonnes of forage legume seed in 1995. This was attributed to the availability of appropriate seed production technology and the presence of a …

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Flowering Cycle-Related Seed Quality Parameters On 15 New Guineagrass (Panicum Maximum Jacq.) Hybrids, R Usberti, A Usberti Jr, R S. Paterniani Jul 2024

Flowering Cycle-Related Seed Quality Parameters On 15 New Guineagrass (Panicum Maximum Jacq.) Hybrids, R Usberti, A Usberti Jr, R S. Paterniani

IGC Proceedings (1977-2023)

Fifteen new guineagrass (Panicum maximum Jacq) hybrids, widely variable in flowering cycles, were tested for eleven seed quality parameters: seed viability (tetrazolium)-TZ; normal germination (with and without previous chemical scarification)-TG and NG; presence of viable seeds after the germination tests- RSTG and RSNG; seed dormancy-DTG and DNG; germination rate-TGR and NGR and seed vigor (after accelerated aging test) -AATG and AANG. The genetic materials used presented no significant differences for tetrazolium seed viability. Late- and intermediate-flowering genotypes showed the highest correlations between flowering cycle and seed quality for TG, NG, TGR and NGR (r= 0.468**; 0.731**; 0.422* and 0.683**, …

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Effect Of Plant Density On Yield And Yield Components And Seed Chemical Composition Of Some Sunflower Varieties, N A. Noueldin, M E. El-Bially, B A. El-Ahmer, M G. El-Baz Jul 2024

Effect Of Plant Density On Yield And Yield Components And Seed Chemical Composition Of Some Sunflower Varieties, N A. Noueldin, M E. El-Bially, B A. El-Ahmer, M G. El-Baz

IGC Proceedings (1977-2023)

The objective of this research is to study the effect of varieties (Mayak, Elorida 2000 and sigce 475), hill distance (20, 30 and 40 cm) and ridge width (50, 60 and 70 cm) on productivity of sunflower (Helianthus annus L.). The highest oil % was obtained by sowing sigco 475 at a 40 cm hills distince under 60 cm. ridge width and the highest oil yield feddan-1* as well as seed yield feddan-1 was obtained by sowing Mayak on 20cm hills under a 50cm ridge width.

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Seed Banks In A Natural Pasture In Tasmania, Australia: Implications For Species Composition Change, D A. Friend, A S. Cameron, A J. Povey, P L. Dolan Jul 2024

Seed Banks In A Natural Pasture In Tasmania, Australia: Implications For Species Composition Change, D A. Friend, A S. Cameron, A J. Povey, P L. Dolan

IGC Proceedings (1977-2023)

Seed banks in a natural pasture in Tasmania were examined as part of a study of the effects of grazing on changes in species composition. The dominant native perennial grasses had relatively low seed banks, whereas annual grasses, sedges, rushes and a number of forbs had relatively high seed banks. The results confirm the vulnerability of the native grasses to local extinction in the event of loss of the established plants, e.g. through overgrazing.

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Tropical Forage Seed Production In Southeast Asia: Current Status And Prospects, C Phaikaew, L Guodao, A Abdullah, M Tuhulele, E Magboo, B Bouahom, W Stur Jul 2024

Tropical Forage Seed Production In Southeast Asia: Current Status And Prospects, C Phaikaew, L Guodao, A Abdullah, M Tuhulele, E Magboo, B Bouahom, W Stur

IGC Proceedings (1977-2023)

The demand for forage seed in southeast Asia has increased in recent years. More than 1,200 tons of seed were produced in Thailand in 1995 with smaller quantities of seed having been produced in China, Lao PDR, Malaysia, Philippines and Indonesia. Large quantities have been produced of Brachiaria ruziziensis, Stylosanthes hamata, Stylosanthes guianensis and Panicum maximum. There are good prospects to increase forage seed production and to develop trade between countries in the southeast Asian region. There is a need to increase seed production of widely adapted species, and expand production of forages for other purposes such as turf …

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Traditional Grassland And Fodder Management Systems In Tanzania And Potential For Improvement, R M. Otsyina, I Essai, D Asenga Jul 2024

Traditional Grassland And Fodder Management Systems In Tanzania And Potential For Improvement, R M. Otsyina, I Essai, D Asenga

IGC Proceedings (1977-2023)

The “Ngitiri” fodder conservation system was developed by the Sukuma agro-pastoralists as a strategy to alleviate acute dry season fodder constraints. This traditional agroforestry system provides the basis and opportunities for development of improved silvipastoral systems. Ngitiri is a major source of dry season fodder supply for livestock and thatch for roofing. The system is widespread in the Sukuma landuse system in central Tanzania. This paper presents the scope and importance of the Ngitiri system, management aspects, constraints, and farmers’ perceptions on improvement. Implications for agroforestry technology development in the Sukuma agropastoral system are also discussed.

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Forage Seed Production In Egypt For Domestic Marker And For Export, M A. El-Nahrawy, A Rammah, O Niemelainen Jul 2024

Forage Seed Production In Egypt For Domestic Marker And For Export, M A. El-Nahrawy, A Rammah, O Niemelainen

IGC Proceedings (1977-2023)

In Egypt, no major effort is made to provide local and export markets with seeds of correctly identified and pure cultivars of forage crops in spite of the existence of all the essential factors for a successful seed industry. A wide genetic base of indigenous forage crops such as berseem clover and alfalfa, proper irrigation, a harvest and seed maturation period free from rain, sunshine and clear sky all year and highly fertile soils in isolated areas are available. Moreover, uncertified, uncontrolled and unidentified local seeds of berseem clover and alfalfa are highly demanded by foreign markets due to their …

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Coastal Infrastructure And Climate Change Adaptation In Bangladesh: Ecosystem Services Insights From An Integrated Ses-Dapsir Framework, Md Monzer Hossain Sarker, Alberto Gabino Martínez-Hernández, Jesús Reyes Vásquez, Perla Rivadeneyra, Sebastian Sebastian Raimondo Jul 2024

Coastal Infrastructure And Climate Change Adaptation In Bangladesh: Ecosystem Services Insights From An Integrated Ses-Dapsir Framework, Md Monzer Hossain Sarker, Alberto Gabino Martínez-Hernández, Jesús Reyes Vásquez, Perla Rivadeneyra, Sebastian Sebastian Raimondo

Fondazione Eni Enrico Mattei Working Papers

The escalating impacts of climate change on coastal regions stress the urgency for effective adaptation strategies, particularly for the case of high-risk countries such as Bangladesh. Nature-based solutions, grey and mixed coastal infrastructure offer promising solutions for addressing these challenges. Prior publications have utilized decision-making models such as the DPSIR framework to explore the link between coastal infrastructure and climate change. However, until now none of them have used it in combination with broader frameworks. Moreover, few works have analyzed the south central coast of Bangladesh by following an integrated approach. Hence, this working paper aims to bridge these gaps …

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Exploring Teacher Perceptions On The Effectiveness Of The Freshman Academy, Renee C. Goode-Boyd Jul 2024

Exploring Teacher Perceptions On The Effectiveness Of The Freshman Academy, Renee C. Goode-Boyd

Walden Dissertations and Doctoral Studies

A Southeastern school district created freshman academies to assist freshman students with strategies and support they need to combat ninth-grade failure successfully, but little change was observed. The purpose of the study was to explore teachers' perceptions of the freshman academy's transition program structure, benefits, challenges, and effectiveness. The conceptual framework for this study encompassed elements of constructivist theory, which explains how children adapt to their environments and learn how to process information successfully. The research questions examined teachers' perceptions regarding the benefits, challenges, and perceived effectiveness of the freshman academy intervention program. The data for this basic qualitative study …

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Facets Of Neuroticism As Predictors Of Heart Rate Variability And Psychological Distress, Mikel Cressman Jul 2024

Facets Of Neuroticism As Predictors Of Heart Rate Variability And Psychological Distress, Mikel Cressman

Theses and Dissertations

Heart rate variability (HRV) and personality are related to both physical and mental health outcomes. Previous research has found a relationship between neuroticism and distress while the findings on the relationship between neuroticism and HRV are mixed. Studying the facets of neuroticism may provide a more nuanced view of the effects of personality on HRV and distress. Previous research has suggested that the vulnerability facet of neuroticism appears to be uniquely related to the cardiovascular response to stress. This study's first hypothesis is that individuals with higher scores on the vulnerability facet will have lower heart rate variability. The second …

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Mdf-Dta: A Multi-Dimensional Fusion Approach For Drug-Target Binding Affinity Prediction, Amit Ranjan, Adam Bess, Chris Alvin, Supratik Mukhopadhyay Jul 2024

Mdf-Dta: A Multi-Dimensional Fusion Approach For Drug-Target Binding Affinity Prediction, Amit Ranjan, Adam Bess, Chris Alvin, Supratik Mukhopadhyay

Faculty Publications

Drug-target affinity (DTA) prediction is an important task in the early stages of drug discovery. Traditional biological approaches are time-consuming, effort-consuming, and resource-consuming due to the large size of genomic and chemical spaces. Computational approaches using machine learning have emerged to narrow down the drug candidate search space. However, most of these prediction models focus on single feature encoding of drugs and targets, ignoring the importance of integrating different dimensions of these features. We propose a deep learning-based approach called Multi-Dimensional Fusion for Drug Target Affinity Prediction (MDF-DTA) incorporating different dimensional features. Our model fuses 1D, 2D, and 3D representations …

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Fundamental Limits In Measuring The Anisotropic Rotational Diffusion Of Single Molecules, Weiyan Zhou, Tingting Wu, Matthew D. Lew Jul 2024

Fundamental Limits In Measuring The Anisotropic Rotational Diffusion Of Single Molecules, Weiyan Zhou, Tingting Wu, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Many biophysical techniques, such as single-molecule fluorescence correlation spectroscopy, Förster resonance energy transfer, and fluorescence anisotropy, measure the translation and rotation of biomolecules to quantify molecular processes at the nanoscale. These methods often simplify data analysis by assuming isotropic rotational diffusion, e.g., that molecules wobble within a circular cone. This simplification ignores the anisotropy present in many biological contexts that may cause molecules to exhibit different degrees of diffusion in different directions. Here, we loosen this assumption and establish a theoretical framework for describing and measuring anisotropic rotational diffusion using fluorescence imaging. We show that anisotropic wobble is directly quantified …

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Phytoplankton Community Dynamics In The Northern California Current System, Kristin E. Forgrave Jul 2024

Phytoplankton Community Dynamics In The Northern California Current System, Kristin E. Forgrave

Dissertations and Theses

The Northern California Current system is a productive coastal ecosystem encompassing a variety of temporal and spatial features. The photosynthetic microbial community plays a crucial role in supporting the rich ecosystem and its economically important fisheries. My research integrates data across location and two years to investigate the community composition of two major phytoplankton groups in this system: picocyanobacteria and photosynthetic picoeukaryotes (PPE). The abundances and sizes of the phytoplankton were measured using flow cytometry. I found PPE present at similar concentrations in both summer and winter seasons. Abundances of both PPE and picocyanobacteria were comparable in the winter, but …

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Adopting Oer Course Materials: Instructor Experiences, Jenny Ceciliano Jul 2024

Adopting Oer Course Materials: Instructor Experiences, Jenny Ceciliano

Dissertations and Theses

Traditional commercial textbooks used in postsecondary courses are often problematic due to their rigidity, tendency to mirror the dominant culture, and the substantial cost imposed upon students. Although replacing these texts with open educational resources (OER) can facilitate more equitable and inclusive pedagogical practices while removing a significant expense, there has been insufficient research surrounding instructors' experience of transitioning from a commercial textbook to OER course materials. Through semi-structured interviews with nine postsecondary instructors who teach with OER course materials, this basic qualitative study explores the experience of that transition. The findings indicate that adopting OER is a challenging and …

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