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The Thin Line In The Bluegrass Schools: A Quantitative Study On How School Resource Officers Impact A School And District's Use Of Exclusionary Discipline In Kentucky, Mia Morales

Theses and Dissertations--Education Sciences

Legislatures across the country have been developing laws and policies to place police officers, also known as School Resource Officers (“SROs”), in schools. A recent piece of legislation in Kentucky, entitled the School Safety and Resiliency Act, requires all school campuses in Kentucky contain at least one SRO. Researchers have found relationships between the presence of SROs and the use of exclusionary discipline, and this research expands on that foundation by looking statewide at school- and district-level variables.

Using a multiple regression model, this research examined the presence of SROs in schools and the ratio of number of SROs to …

Genetic Expression Changes And Pathologic Findings Associated With Hyperhomocysteinemia In Human Autopsy Brain Tissue, Erica M. Weekman, Zachary Winder, Colin B. Rogers, Erin L. Abner, Tiffany L. Sudduth, Ela Patel, Adam J. Dugan, Shuling X. Fister, Brandi Wasek, Peter T. Nelson, Gregory A. Jicha, Teodoro Bottiglieri, David W. Fardo, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Introduction: Vascular contributions to cognitive impairment and dementia (VCID) are a leading cause of dementia. An underappreciated, modifiable risk factor for VCID is hyperhomocysteinemia (HHcy), defined by elevated levels of plasma homocysteine, most often due to impaired B vitamin absorption in aged persons. Studies aimed at identifying neuropathologic features and gene expression profiles associated with HHcy have been lacking.

Methods: A subset of research volunteers from the University of Kentucky Alzheimer’s Disease Research Center longitudinal cohort came to autopsy and had ante mortem plasma homocysteine levels available. Brain tissue and blood plasma drawn closest to death were used to measure …

Forage News [2022-12], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.

Apoe Genetics Influence Murine Gut Microbiome, Diana J. Zajac, Stefan J. Green, Lance A. Johnson, Steven Estus

Sanders-Brown Center on Aging Faculty Publications

Apolipoprotein E (APOE) alleles impact pathogenesis and risk for multiple human diseases, making them primary targets for disease treatment and prevention. Previously, we and others reported an association between APOE alleles and the gut microbiome. Here, we evaluated effects of APOE heterozygosity and tested whether these overall results extended to mice maintained under ideal conditions for microbiome analyses. To model human APOE alleles, this study used APOE targeted replacement (TR) mice on a C57Bl/6 background. To minimize genetic drift, homozygous APOE3 mice were crossed to homozygous APOE2 or homozygous APOE4 mice prior to the study, and the resulting …

Single Low-Dose Targeted Bevacizumab Infusion In Adult Patients With Steroid-Refractory Radiation Necrosis Of The Brain: A Phase Ii Open-Label Prospective Clinical Trial, Shervin R. Dashti, Robert J. Kadner, Bradley S. Folley, Jason P. Sheehan, Dong Y. Han, Richard J. Kryscio, Mary B. Carter, Lisa B. E. Shields, Brian M. Plato, Renato V. La Rocca, Aaron C. Spalding, Tom L. Yao, Justin F. Fraser

Sanders-Brown Center on Aging Faculty Publications

OBJECTIVE There is an unmet need for safe and rapidly effective therapies for refractory brain radiation necrosis (RN). The aim of this prospective single-arm phase II trial was to evaluate the safety and efficacy of a single low-dose targeted bevacizumab infusion after blood-brain barrier disruption (BBBD) in adult patients with steroid-refractory brain RN.

METHODS Ten adults with steroid-refractory, imaging-confirmed brain RN were enrolled between November 2016 and January 2018 and followed for 12 months after treatment. Bevacizumab 2.5 mg/kg was administered as a one-time targeted intra-arterial infusion immediately after BBBD. Primary outcomes included safety and > 25% decrease in lesion volume. …

Effects Of Sowing Date And Phosphorus Fertiliser Application On Winter Survival Of Lucerne Cv. Aohan In The Northern Semi-Arid Region Of China, Z. L. Wang, Q. Zh. Sun, Y. W. Wang, Zh. Y. Li, Sh. F. Zhao

IGC Proceedings (1977-2023)

In the northern semi-arid region of China, winter survival is always a limiting factor for lucerne production, because low temperatures and a dry climate in winter (Zhou et al., 1993; Ma, 2000; Sun & Gui, 2001; Sun et al., 2003). An experiment was conducted to find an appropriate sowing date and P application rate in order to improve lucerne winter survival.

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 (1977-2023)

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 Influence Of Fertiliser Application To Strip-Sown Grasslands On Herbage Production And Quality, A. Kohoutek, P. Komárek, V. Odstrčilová, P. Nerušil

IGC Proceedings (1977-2023)

To increase the productivity of dairy cattle in the Czech Republic requires an improvement in herbage quality and an increase in the net energy of herbage. The decrease in cattle numbers by 50 % and the expansion of the grassland area both result in a surplus of feedstuffs of low quality. Introduction of strip-seeding of legumes and grasses into grasslands in interaction with fertilisation provides a possible solution to this problem.

Range-Based Livestock Production In Turkmenistan, R. H. Behnke, G. Davidson

IGC Proceedings (1977-2023)

Turkmenistan retains a centralized system of livestock production in which many critical assets are owned by the state. Though technically in the temperate zone, the country's climate is harsh and unstable. Groundwater resources are unevenly distributed, leaving many potential grazing areas seasonally inaccessible due to lack of drinking water for livestock. This paper summarizes the results of a three-year study of rangelands, livestock production, flock economics and land tenure at two study sites, one in central and the other in eastern Turkmenistan. The results of this study suggest that pastoral communities in Turkmenistan have coped remarkably well with the institutional …

Rangeland Ecological Management Counter-Measures Study Of Xinjiang, H. X. Cui, J. Li, S. Asiya, J. L. Zhang, Jialin

IGC Proceedings (1977-2023)

Xinjiang is located in the hinterland of the Asian-Euro continental area and far from the ocean. It is surrounded by mountains and forms a physiognomic landscape of two basins located in three mountains. This results in an extremely droughty continental climate and a harsh environment in the Temperate Zone. However, the geographical environment is diverse in the Xinjiang Autonomous region, the three high mountains and complicated geographical structure results in changes in ecological conditions with altitude and a diverse ecological environment. Because of the drought characteristics the desert area has developed different types of vegetation, and the complexity of the …

Nitrogen Dynamics Following The Break-Up Of Grassland On Three Different Sandy Soils, Manfred Kayser, K. Seidel, J. Müller

IGC Proceedings (1977-2023)

Nitrogen (N) is accumulated under grassland depending on factors such as soil type, management, and fertiliser input. Break-up of grassland stimulates mineralisation of organic N and may lead to increased soil mineral N and leaching losses (Lloyd, 1992). The objective of this study was to find out how site factors, e.g. soil, previous management and sward age, the following crop and the new level of N fertiliser affect the amount of inorganic N in autumn and the preceding mineralisation processes when grassland is ploughed in spring.

Leaching Losses Of N, P And K From Grazed Legume Based Swards: Some Preliminary Results, E. R. Dixon, A. C. Stone, D. Scholefield, D. J. Hatch

IGC Proceedings (1977-2023)

There is increasing interest in sustainable agricultural systems because of environmental concerns. Animal production which utilises mixed grass and legume swards could be an effective measure in increasing the efficiency of nutrient utilisation, and investigation into different legume species is necessary. Leaching losses of N, P and K from 3 legume species under grazing by sheep were measured using Teflon-coated suction cups. The experiment took place on the UK site of the EU-funded, multi-site experiment – LEGGRAZE.

Maximising Slurry Crop Available Nitrogen Utilisation In Grassland Systems, J. R. Williams, E. Sagoo, B. J. Chambers, J. Laws, D. R. Chadwick

IGC Proceedings (1977-2023)

In the UK, approximately 90 million tonnes of animal manure containing ca 450,000 tonnes of nitrogen (N) are recycled to agricultural land each year. The efficient utilisation of manure N can save farmers money and reduce diffuse air (ammonia) and water (nitrate) pollution. For slurries, bandspreading techniques (e.g. trailing shoe and trailing hose) can improve N utilisation by reducing ammonia volatilisation losses compared with conventional broadcast applications. They also provide increased spreading opportunities in spring/summer as slurry is placed in a band on the soil surface limiting herbage contamination, which can reduce the need to apply slurry in the autumn/early …

Phosphorus Transfer To River Water From Grassland Catchments In Ireland, H. Tunney, P. Jordan, G. Kiely, R. Moles, G. Morgan, P. Byrne, W. Menary, K. Daly

IGC Proceedings (1977-2023)

In Ireland it is estimated that at least half of phosphorus (P) loss to water is from agricultural sources and National and European Union policy and legislation aim at reducing phosphorus (P) loss to water in order to reduce eutrophication. In Ireland, the average soil test P (STP) levels increased ten-fold, from less than 1 to over 8 mg Morgan P per l soil over the past 50 years, reflecting increased P inputs in fertiliser and animal feed. One of the main objectives of this three-year research programme, started in 2001, was to investigate P loss to water in grassland …

Supplementation Of Cattle With Rock Phosphate And Urea Treated Straw To Improve Manure Quality And Crop Yields In The Sahel Zone Of Senegal, Maimouna Cissé, M. N’Diaye, C. M. N’Dione

IGC Proceedings (1977-2023)

Mineral deficiencies are a major constraint in improving animal production and crop yield in the Sahel zone (Cissé et al., 1996). Millet (Pennisetum glaucum) and groundnut (Arachis hypogaea,) are two major food and cash crops in this zone. The purpose of this study was to assess effects of supplementing grazing cattle with rock phosphate and nitrogen enriched diets on animal performances, and the effects of the application of their manure on crop yield in a pearl millet-groundnut rotational system located in N Senegal.

Characterisation Of Soil Organic Matter From Pensacola Bahiagrass Pastures Grazed For Four Years At Different Management Intensities, J. C. B. Dubeux Jr., Lynn E. Sollenberger, N. B. Comerford, Ana C. Ruggieri, K. M. Portier

IGC Proceedings (1977-2023)

Soil fertility and agricultural system sustainability depend upon soil organic matter (SOM), particularly in the tropics, because of highly weathered soils and low fertiliser inputs. Because of the beneficial effects of SOM on chemical, physical, and biological soil properties, Greenland (1994) suggested that SOM is an indicator of agro-ecosystem sustainability. Pasture management may affect SOM by altering the production/decomposition ratio of residues (Johnson, 1995). The objective of this study was to characterise the SOM of Pensacola bahiagrass pastures grazed for four years at a range of management intensities.

N-Mineralisation And Phosphorous: Important Elements In Decision Support For Grassland Systems, A. L. Nielsen, C. C. Hoffmann

IGC Proceedings (1977-2023)

Leaching of N and P from extensively managed grasslands on organic soils varies considerably. In environmentally sensitive areas it is important to diminish leaching by appropriate agricultural management. In Denmark low grazing intensity and management without fertilisation have been given a high priority. The type of soil has not been equally in focus, and it seems that the effect of cutting, compared with grazing, results in a higher removal of nutrients (e.g. Benke et al., 1992) can be used more strategically. The objective of this case study was to combine data from management strategies with data from leaching studies …

Effect Of Different Carbon And Nitrogen Inputs On Soil Chemical And Biochemical Properties In Maize-Based Forage Systems In Northern Italy, S. Monaco, D. Hatch, L. Dixon, C. Grignani, D. Sacco, L. Zavattaro

IGC Proceedings (1977-2023)

In agroecosystems, manure application and straw return affect carbon (C) and nitrogen (N) cycling and affect soil organic matter (SOM), nutrient supply and losses to the environment. We examined effects of different organic sources on crop production, N uptake and surplus and SOM in maize systems.

Nitrogen Leaching From Cattle, Sheep And Deer Grazed Pastures In New Zealand, Keith Betteridge, Sterwart F. Ledgard, Coby J. Hoogendoorn, M. G. Lambert, Z. A. Park, Des A. Costall, P. W. Theobald

IGC Proceedings (1977-2023)

The impacts of intensified grazing in New Zealand are being reflected in declining quality of groundwater, streams and lake water. Manipulation of ratios of grazing animal species may be one way farmers can reduce nitrogen (N) emissions to ground water. The present research quantifies nitrate and ammonium leaching losses from rotationally grazed sheep, cattle and deer pastures in a common environment.

Changes In Nutrient Turnover And Supply During The Reversion Of Arable Land To Acid Grassland/Calluna Heathland, A. Bhogal, B. J. Chambers, R. Pywell, K. Walker

IGC Proceedings (1977-2023)

Lowland heath is of high conservation value because of the specialised and rare assemblages of plants and animals that it supports. Combinations of agricultural and urban development, and lack of appropriate management have resulted in large-scale loss and fragmentation of this habitat throughout the UK. Current UK conservation policies seek to re-create 6,000 ha of this habitat on land previously in agricultural and forestry production. Previous research indicated that high soil pH and fertility, together with a lack of propagules of heathland species, made it difficult to achieve this objective. The aim was to evaluate techniques to establish grass-Calluna …

The Effect Of A Reduction In Phosphate Application On Soil Phosphate Pools, C. Van Der Salm, J. Van Middelkoop, P. A. I. Ehlert

IGC Proceedings (1977-2023)

Excessive use of manure and fertilisers in western Europe has led to high phosphorus (P) contents in many agricultural soils leading to environmental P losses by overland flow, subsurface drainage and leaching to groundwater. To stop phosphate build up in the soil and leaching to surface and ground waters, the Dutch government is gradually reducing allowable phosphate application on grassland from 130 kg/ha per year in 2005 to 90 kg/ha per year in 2015. This will lead to a reduction of the phosphate surplus from 40 in 2005 to 0 kg/ha per year. To investigate the impact of reductions in …

Within Resting Period Seasonal Soluble Carbohydrate Profiles Of Rotationally Grazed Elephant Grass, L. P. Passos, M. C. Vidigal, I. G. Perry, Fermino Deresz, F. B. De Sousa

IGC Proceedings (1977-2023)

Recent evidence indicates that carbohydrate-rich grazed herbage is effective for improving milk production (Trevaskis et al., 2004). However, the dynamics of water-soluble carbohydrate (WSC) seasonal accumulation as related to forage availability remains unknown, especially during the growth stage of tropical forage grazing systems. The objective of the work was to verify the seasonal WSC profiles of rotationally grazed elephantgrass (Pennisetum purpureum Schum.), by making measurements within each 30-day resting period.

Field Experiments To Help Optimise Nitrogen Fixation By Legumes On Organic Farms, A. Joynes, D. J. Hatch, A. Stone, S. Cuttle, G. Goodlass

IGC Proceedings (1977-2023)

During an organic rotation, the aim is to increase the nitrogen (N) content of the soil (and hence build up soil fertility) by recycling crop residues, applying manures/composts and from N fixed by legumes. IGER, with ADAS, Duchy College Cornwall and Abacus Organic Associates are developing improved guidance for organic farmers in the use of fertility-building crops. The main questions are: how to maximise N fixation and how to make the most efficient use of the fixed N? Available soil mineral N, which is generally thought to reduce N fixation, will be increased by manure applications, cutting/mulching and grazing. We …

The Effect Of Forage Legumes On Mineral Nitrogen Content In Soil, M. Isolahti, A. Huuskonen, M. Tuori, Oiva Nissinen, R. Nevalainen

IGC Proceedings (1977-2023)

The cultivation of forage legumes is often suggested as a possibility to improve nitrogen (N) utilisation in farming. However, previous studies have indicated examples in which the cultivation of legumes such as white clover has led to accumulation of large amounts of N in soil (Adams & Pattison, 1985). In this study the potential risks of N leaching were estimated by determining amount of mineral N in the soil.

Study Of Characteristics Of Soil Animals In Halophilous Plant Communities Of Leymus Chinensis Grasslands Of Northeast In China, Xiuqin Yin, Y. Zhang, W. Dong

IGC Proceedings (1977-2023)

We have researched soil animals in 8 types of halophilous plant communities of Leymus chinensis grasslands of Northeast China to characterise soil animal groups and explain the role and function of soil animals in grassland ecosystems (Richard & Roger, 1998) and provide a scientific basis for research to improve alkaline lands in these grasslands.

Grassland Management Practices And The Diversity Of Soil Nematode Communities, R. Cook, P. J. Murray, K. A. Mizen

IGC Proceedings (1977-2023)

Nematodes are numerically abundant in northern temperate grassland soils where, through their feeding on plants, soil microbes and each other as well as being a food resource, they contribute to soil functioning and affect plant soil interrelationships. Permanent plant cover and the consequent abundance of root tissue supply a year-round food supply. There are only limited data on the effects of root-feeding by nematodes on the growth and development of pasture plants but under some circumstances above-ground biomass may be reduced. Herbivory by specific nematode parasites may not only directly affect the host plant but also promote soil microbial activity …

The Addition And Cessation Of Inorganic Fertiliser Amendments In Long-Term Managed Grasslands: Impacts On Above And Below-Ground Communities, C. D. Clegg, P. J. Murray, R. Cook, T. Tallec

IGC Proceedings (1977-2023)

In recent times, land use in the United Kingdom has undergone considerable changes because of social and economic pressures, leading to a fine balance between the demands of highly productive intensive systems and practices which are perceived to be more environmentally acceptable. Plant productivity is governed by the supply of nutrients from the soil, which in turn is dependent on the dynamics of organic matter decomposition driven by soil micro-, meso- and macro fauna. Considerable information is available concerning the impact of inorganic fertiliser additions on communities of macro-fauna and flora, but the effects on specific microbial communities in soils …

Cycling Of N And P In Grass-Alone (Brachiaria) And Mixed Grass/Legume (Brachiaria/ Desmodium Ovalifolium) Grazed Pastures In The Atlantic Forest Region Of Brazil, R. M. Boddey, R. Tarré, R. Macedo, C. De P. Rezende, J. M. Pereira, B. J. R. Alves, S. Urquiaga

IGC Proceedings (1977-2023)

There are estimated to be > 80 M ha of Brachiaria pastures in the tropical regions of Brazil. When continuously grazed with only modest fertiliser inputs (and no N) these pastures can maintain reasonable cattle weight gains (> 200 kg LWG/ha per year). However, without fertiliser and when overgrazed, LWGs fall rapidly to low levels. Recent studies have shown that N and P deficiency are the most important factors limiting productivity. The objective of this study was to study fluxes of N and P in the pasture system in order to understand resilience to poor management and minimum nutrient requirements to …

Integrating Below-Ground Ecology Into Sustainable Grassland Management, R. D. Bardgett

IGC Proceedings (1977-2023)

Key points

1. Grasslands produce soils that sustain an abundant and diverse soil food web, providing tremendous opportunity for below-ground interactions to influence nutrient cycling processes and plant production.

2. Fast developing areas of ecological science offer scope to harness positive outcomes of below-ground ecology for enhancing efficient cycling of nutrients in sustainable grassland systems.

The Influence Of Burning On Soil Microbial Biomass And Activity Along The Boro Route In The Okavango Delta Of Botswana, Tabo Mubyana-John, A. Banda

IGC Proceedings (1977-2023)

The Okavango Delta, a protected area in northeastern Botswana because of its annual flooding pattern, is the main source of water in an otherwise arid environment with a high diversity of plants and animals and forms the main tourist area in the region. However, the area is under threat from range fires. The objective of this study was to assess the influence of fire on soil microbial activity, biomass C, fungal population and diversity, and some soil properties along the Boro route of the Okavango Delta (Botswana).