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University of Kentucky

2015

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Articles 271 - 300 of 311

Full-Text Articles in Physical Sciences and Mathematics

Nitrogen Management Of Forages In Relation To Gaseous Emissions – New Approaches And Considerations, Shabtai Bittman, Derek Hunt Jan 2015

Nitrogen Management Of Forages In Relation To Gaseous Emissions – New Approaches And Considerations, Shabtai Bittman, Derek Hunt

IGC Proceedings (1997-2023)

Forages have a high N demand, a long growing season, and an effective root system all contributing to effective nutrient capture. However forages are restrictive in methods available for mitigating gaseous losses both as NH3 and as N2O, due to both practical and cost considerations. Strategies are needed to address the challenges of both N efficiency and N losses. Agronomic techniques in long term experiments can enhance estimates of N loss pathways and N efficiency, and demonstrate the importance of integrated multinutrient approaches. The dual manure stream concept divides manure into a thin fraction suitable as an …


Productivity And Biological Nitrogen Fixation Of Different Species Of Vetches (Vicia Spp.) Under The Rainfed Conditions Of West Asia, Ali Abd El Moneim, Mohan C. Saxena Jan 2015

Productivity And Biological Nitrogen Fixation Of Different Species Of Vetches (Vicia Spp.) Under The Rainfed Conditions Of West Asia, Ali Abd El Moneim, Mohan C. Saxena

IGC Proceedings (1997-2023)

The low rainfall areas of West Asia are characterized by pastoral production system primarily based on small ruminants (sheep and goats). Rangelands serve as the main source of feed. With increasing population, the demand for livestock products has increased. As a consequence, the stocking rates have soared, increasing the pressure on rangelands. Rangeland degradation has therefore been increasing threatening the sustainability of livestock production system and the livelihood of the people dependent on it. Production of additional feed is essential to reduce the pressure on rangelands. Vetches (Vicia spp.) are endemic in the area and can be potential source …


Strengthening Livelihood Of Rural Farmer Populations Through Improved Grasslands, Sujatha Premaratne, S. C. Somasiri Jan 2015

Strengthening Livelihood Of Rural Farmer Populations Through Improved Grasslands, Sujatha Premaratne, S. C. Somasiri

IGC Proceedings (1997-2023)

This paper reviews the current background of the grassland resource with a purpose of livestock perspective to improve the livelihood of rural farmers. The use of grasslands for livestock rearing by rural farmers has been a long tradition. In climate and vegetation contrast, these grasslands are much more diverse. They are likely to play an economical role in increasing the milk production in many Asian countries. With an increase of human population, the traditional feeding, breeding and surviving habitats for livestock have been acutely restricted in many countries. Therefore, a continued effort is needed to maintain production for sustainable management …


Impact Of Market Forces On Product Quality And Grassland Condition, David L. Michalk, Jianping Wu, Warwick B. Badgery, David R. Kemp Jan 2015

Impact Of Market Forces On Product Quality And Grassland Condition, David L. Michalk, Jianping Wu, Warwick B. Badgery, David R. Kemp

IGC Proceedings (1997-2023)

Meeting demands for livestock products which are predicted to more than double during the next 20 years, is central to the challenge of feeding the world sustainably. Smallholders will play a key role in achieving global security in animal protein. However, this requires a shift from subsistence to market-oriented farming where production efficiency not the number of livestock is the key focus with the aim of producing ‘more from less’. For grassland-based ruminant production, reducing stocking rate from current unsustainable levels under subsistence management is an essential first step to producing more production and profit from fewer animals. This is …


Stakeholders Integration For Sustainable Use Of Temperate Forage/Livestock Agriculture, Garry D. Lacefield, Don Ball Jan 2015

Stakeholders Integration For Sustainable Use Of Temperate Forage/Livestock Agriculture, Garry D. Lacefield, Don Ball

IGC Proceedings (1997-2023)

Forage/livestock production is complex, and best management options are often site-specific, but some concepts have broad application. The intent of this article is to provide an overview of research-based management approaches that the authors believe are necessary to ensure the sustainability of forage/livestock farms. This overview discussion is needed because livestock agriculture is changing, thus creating both challenges and opportunities for producers. In the last 30 years, beef numbers in the USA have declined by 20%, but production per cow has more than doubled, resulting in increased total production on less land with fewer animals. Similar statistics exist for the …


Sustainable Grasslands: Resolving Management Options For Livelihood And Environmental Benefits, David R. Kemp, Warwick B. Badgery, David L. Michalk Jan 2015

Sustainable Grasslands: Resolving Management Options For Livelihood And Environmental Benefits, David R. Kemp, Warwick B. Badgery, David L. Michalk

IGC Proceedings (1997-2023)

To help solve the major issues of improving livelihoods and environmental services, grassland research needs to be evaluated within the context of relevant farm systems. Treatments need to show that they not only have significant effects but that they have effects that are meaningful in the context of the relevant farm system. Research often defines an optimum criterion for management that is a single point, but that is difficult to achieve in practice, especially when there are several components in a grassland system that need to be optimised. It is argued that an appropriate criterion for optimising management is a …


Changing Grassland Scenario In Developing Countries--Economical And Social Perspective, Abule Ebro Jan 2015

Changing Grassland Scenario In Developing Countries--Economical And Social Perspective, Abule Ebro

IGC Proceedings (1997-2023)

Grasslands are mainly used for livestock production in developing countries although they have been facing contradictory pressures, i.e., increased demand for natural resources and animal products to cope with rising human populations. On the other, there is a need to preserve the environment and ecosystem. This paper reviewed the causes of grassland changes, the economic and social perspective of changing grasslands with more emphasis on dry lands. Different indicators were used to assess the economic (livestock production, wildlife and tourism, crop production, ecosystem services) and social (traditional institutions, mobility, land tenure and grazing systems) perspectives of changing grassland. The major …


Management Of Grazing Lands Through Educating Communities, D. Ariungerel, Graeme Hand, Annabel Walsh Jan 2015

Management Of Grazing Lands Through Educating Communities, D. Ariungerel, Graeme Hand, Annabel Walsh

IGC Proceedings (1997-2023)

The Mongolian steppe is one of the world’s largest grassland and it is an arid to semiarid land with a strong climate gradient. Biodiversity loss leading to desertification and land degradation is estimated to be impacting around 65% of the total area of Mongolia. The preliminary objective of this project was to trial the Positive Deviance Methodology to determine if this method assists herders to design behaviors to reverse this biodiversity loss. This project is a partnership between Mongolian Herders, Mongolian rangeland scientists and Australian based Stipa Native Grasses Association. The Positive Deviance Methodology has five basic steps based around …


Ecologically And Socially Sustainable Livestock Development In Marginal Areas, Ilse Köhler-Rollefson Jan 2015

Ecologically And Socially Sustainable Livestock Development In Marginal Areas, Ilse Köhler-Rollefson

IGC Proceedings (1997-2023)

“Marginal areas” are perceived as difficult and unproductive landscapes, always under the threat of drought, desertification and poverty. Yet, both dryland and high altitude marginal areas have an extraordinary output of livestock products; in the efficiency of producing human-edible protein they far surpass more fertile areas. This productivity under adverse climatic conditions rests on sophisticated strategies and social institutions developed by pastoral communities to deal with variability in the availability of resources. It depends on the use of animal genetic resources that are adapted to make best use of local vegetation and can cope with seasonal variations in availability. Livestock …


Valuing Variability--New Perspectives On Climate Resilient Dryland Development, Saverio Kratli Jan 2015

Valuing Variability--New Perspectives On Climate Resilient Dryland Development, Saverio Kratli

IGC Proceedings (1997-2023)

Valuing Variability is a challenge to the view of the drylands as naturally vulnerable to food insecurity and poverty. It argues that improving agricultural productivity in dryland environments is possible by working with climatic uncertainty rather than seeking to control it – a view that runs contrary to decades of development practice in arid and semi-arid lands.


Livestock And Local Development: Going To A New Humananimal Relationship, Jean François Tourrand, Laurent Dobremez, Benoit Dedieu, Guillaume Duteurtre, M. G. Piketty, P. Lescoat, B. Hubert Jan 2015

Livestock And Local Development: Going To A New Humananimal Relationship, Jean François Tourrand, Laurent Dobremez, Benoit Dedieu, Guillaume Duteurtre, M. G. Piketty, P. Lescoat, B. Hubert

IGC Proceedings (1997-2023)

Along the past ten years, the French National Agency for Research (ANR) has financed projects regarding livestock. Results of five projects were gathered to understand the long-term livestock trends. At the end of the 19th century, animal breeding was oriented towards the production of goods to meet the local, regional, national and global demand, according to the zone. The market gradually became the key-factor to norm both production and consumption. It is now integrating environmental norms and is starting to invest in the social domain. However, this economical vision of animal production does not take into account the other functions …


Breeding Strategies To Improve Fodder Legumes With Special Emphasis On Clover And Medics, Ajoy K. Roy, D. R. Malaviya, P. Kaushal Jan 2015

Breeding Strategies To Improve Fodder Legumes With Special Emphasis On Clover And Medics, Ajoy K. Roy, D. R. Malaviya, P. Kaushal

IGC Proceedings (1997-2023)

In India, Forage has a unique integration of agriculture and animal industry in diversified rich cultural environment. Greater part of rural economy in India relies much upon mixed farming system, a well-knit combination of crop production and livestock rearing. In India, grazing-based livestock husbandry plays an important role in the rural economy as around 50% of animals depend on grazing. Pasturelands over an area of 12 Mha constitute the main grazing resources that are available. Nearly 30 pastoral communities in hilly or arid/semi-arid regions in northern and western parts of India, depend on grazing-based livestock production. Nomadic pastoralism, a traditional …


Climate Change Impact And Adaptation In Temperate Grassland And Livestock Industries, Afshin Ghahramani, Andrew D. Moore Jan 2015

Climate Change Impact And Adaptation In Temperate Grassland And Livestock Industries, Afshin Ghahramani, Andrew D. Moore

IGC Proceedings (1997-2023)

Climate is projected to have negative impact on temperate grassland and livestock productions across the globe. Moderately elevated atmospheric CO2 in the near future is expected to increase plant photosynthetic rates but this is likely to be limited by soil nitrogen deficits. However, in Australia at least it is unlikely that positive effect of elevated CO2 on plant production be able to offset the negative impacts of climate change. Currently there is a considerable gap between actual and achievable production and profit in Australian grazing systems and many management and genetic improvements for climate adaptation would operate by …


Tropical Grassland Ecosystems And Climate Change, C. R. Babu, Vivek Kr. Choudhary, Vijay Kumar Jan 2015

Tropical Grassland Ecosystems And Climate Change, C. R. Babu, Vivek Kr. Choudhary, Vijay Kumar

IGC Proceedings (1997-2023)

Grasses are unique group of flowering plants that form the foundation for the trophic structure in terrestrial communities. The grasses are found in every conceivable habitat where plants can thrive – from sea to deserts and from wetlands to peaks of highest mountains. The grasses form a distinct biome – a major ecological formation in the global classification of vegetation.


Grassland And Livestock Production: The East African Case, David Miano Mwangi Jan 2015

Grassland And Livestock Production: The East African Case, David Miano Mwangi

IGC Proceedings (1997-2023)

Grasslands cover over 26% of the world land mass and about 80% of the agricultural area. They are the source of a livelihood for about 1 million people in the developing countries. Livestock contributes 40% of the global value of agricultural outputs. Approximately 60% of rural households keep livestock. In East Africa there are a number of grasslands. The most extensive of these are the Acacia based Savanna grasslands. Others include the sudd flooded grasslands of South Sudan and the Miobo woodlands of Tanzania. More than 60% of the livestock and wildlife in this region are found on these grasslands. …


Tropical Grasslands--Trends, Perspectives And Future Prospects, Panjab Singh Jan 2015

Tropical Grasslands--Trends, Perspectives And Future Prospects, Panjab Singh

IGC Proceedings (1997-2023)

This paper attempts a rapid summary of the present day state of tropical grassland and livestock based production systems globally, especially in tropics, in relation to recent trends, future assessment, grassland rehabilitation and management strategies, future perspectives of grassland science and development including policy imperatives.


Use Of Lidar-Derived Terrain And Vegetation Information In A Deciduous Forest In Kentucky, Wesley A. Staats Jan 2015

Use Of Lidar-Derived Terrain And Vegetation Information In A Deciduous Forest In Kentucky, Wesley A. Staats

Theses and Dissertations--Forestry and Natural Resources

The use of Light Detection and Ranging (LiDAR) information is gaining popularity, however its use has been limited in deciduous forests. This thesis describes two studies using LiDAR data in an Eastern Kentucky deciduous forest. The first study quantifies vertical error of LiDAR derived digital elevation models (DEMs) which describe the forests terrain. The study uses a new method which eliminates Global Positioning System (GPS) error. The study found that slope and slope variability both significantly affect DEM error and should be taken in to account when using LiDAR derived DEMs. The second study uses LiDAR derived forest vegetation and …


Empirical Likelihood Confidence Band, Shihong Zhu Jan 2015

Empirical Likelihood Confidence Band, Shihong Zhu

Theses and Dissertations--Statistics

The confidence band represents an important measure of uncertainty associated with a functional estimator and empirical likelihood method has been proved to be a viable approach to constructing confidence bands in many cases. Using the empirical likelihood ratio principle, this dissertation developed simultaneous confidence bands for many functions of fundamental importance in survival analysis, including the survival function, the difference and ratio of survival functions, the hazards ratio function, and other parameters involving residual lifetimes. Covariate adjustment was incorporated under the proportional hazards assumption. The proposed method can be very useful when, for example, an individualized survival function is desired …


New Results In Ell_1 Penalized Regression, Edward A. Roualdes Jan 2015

New Results In Ell_1 Penalized Regression, Edward A. Roualdes

Theses and Dissertations--Statistics

Here we consider penalized regression methods, and extend on the results surrounding the l1 norm penalty. We address a more recent development that generalizes previous methods by penalizing a linear transformation of the coefficients of interest instead of penalizing just the coefficients themselves. We introduce an approximate algorithm to fit this generalization and a fully Bayesian hierarchical model that is a direct analogue of the frequentist version. A number of benefits are derived from the Bayesian persepective; most notably choice of the tuning parameter and natural means to estimate the variation of estimates – a notoriously difficult task for the …


Towards Intelligent Telerobotics: Visualization And Control Of Remote Robot, Bo Fu Jan 2015

Towards Intelligent Telerobotics: Visualization And Control Of Remote Robot, Bo Fu

Theses and Dissertations--Computer Science

Human-machine cooperative or co-robotics has been recognized as the next generation of robotics. In contrast to current systems that use limited-reasoning strategies or address problems in narrow contexts, new co-robot systems will be characterized by their flexibility, resourcefulness, varied modeling or reasoning approaches, and use of real-world data in real time, demonstrating a level of intelligence and adaptability seen in humans and animals. The research I focused is in the two sub-field of co-robotics: teleoperation and telepresence. We firstly explore the ways of teleoperation using mixed reality techniques. I proposed a new type of display: hybrid-reality display (HRD) system, which …


High Quality Human 3d Body Modeling, Tracking And Application, Qing Zhang Jan 2015

High Quality Human 3d Body Modeling, Tracking And Application, Qing Zhang

Theses and Dissertations--Computer Science

Geometric reconstruction of dynamic objects is a fundamental task of computer vision and graphics, and modeling human body of high fidelity is considered to be a core of this problem. Traditional human shape and motion capture techniques require an array of surrounding cameras or subjects wear reflective markers, resulting in a limitation of working space and portability. In this dissertation, a complete process is designed from geometric modeling detailed 3D human full body and capturing shape dynamics over time using a flexible setup to guiding clothes/person re-targeting with such data-driven models. As the mechanical movement of human body can be …


Determinantal Ideals From Symmetrized Skew Tableaux, Bill Robinson Jan 2015

Determinantal Ideals From Symmetrized Skew Tableaux, Bill Robinson

Theses and Dissertations--Mathematics

We study a class of determinantal ideals called skew tableau ideals, which are generated by t x t minors in a subset of a symmetric matrix of indeterminates. The initial ideals have been studied in the 2 x 2 case by Corso, Nagel, Petrovic and Yuen. Using liaison techniques, we have extended their results to include the original determinantal ideals in the 2 x 2 case, as well as special cases of the ideals in the t x t case. In particular, for any skew tableau ideal of this form, we have defined an elementary biliaison between it and one …


Nonlinear Hierarchical Models For Longitudinal Experimental Infection Studies, Michael David Singleton Jan 2015

Nonlinear Hierarchical Models For Longitudinal Experimental Infection Studies, Michael David Singleton

Theses and Dissertations--Epidemiology and Biostatistics

Experimental infection (EI) studies, involving the intentional inoculation of animal or human subjects with an infectious agent under controlled conditions, have a long history in infectious disease research. Longitudinal infection response data often arise in EI studies designed to demonstrate vaccine efficacy, explore disease etiology, pathogenesis and transmission, or understand the host immune response to infection. Viral loads, antibody titers, symptom scores and body temperature are a few of the outcome variables commonly studied. Longitudinal EI data are inherently nonlinear, often with single-peaked response trajectories with a common pre- and post-infection baseline. Such data are frequently analyzed with statistical methods …


Singular Value Computation And Subspace Clustering, Qiao Liang Jan 2015

Singular Value Computation And Subspace Clustering, Qiao Liang

Theses and Dissertations--Mathematics

In this dissertation we discuss two problems. In the first part, we consider the problem of computing a few extreme eigenvalues of a symmetric definite generalized eigenvalue problem or a few extreme singular values of a large and sparse matrix. The standard method of choice of computing a few extreme eigenvalues of a large symmetric matrix is the Lanczos or the implicitly restarted Lanczos method. These methods usually employ a shift-and-invert transformation to accelerate the speed of convergence, which is not practical for truly large problems. With this in mind, Golub and Ye proposes an inverse-free preconditioned Krylov subspace method, …


Polyhedral Problems In Combinatorial Convex Geometry, Liam Solus Jan 2015

Polyhedral Problems In Combinatorial Convex Geometry, Liam Solus

Theses and Dissertations--Mathematics

In this dissertation, we exhibit two instances of polyhedra in combinatorial convex geometry. The first instance arises in the context of Ehrhart theory, and the polyhedra are the central objects of study. The second instance arises in algebraic statistics, and the polyhedra act as a conduit through which we study a nonpolyhedral problem.

In the first case, we examine combinatorial and algebraic properties of the Ehrhart h*-polynomial of the r-stable (n,k)-hypersimplices. These are a family of polytopes which form a nested chain of subpolytopes within the (n,k)-hypersimplex. We show that a well-studied unimodular triangulation of the (n,k)-hypersimplex restricts to a …


Selective Tripodal Titanium Silsesquioxane Catalysts For The Epoxidation Of Unactivated Olefins, Sarah M. Peak Jan 2015

Selective Tripodal Titanium Silsesquioxane Catalysts For The Epoxidation Of Unactivated Olefins, Sarah M. Peak

Theses and Dissertations--Chemistry

Regiomeric mixture of HMe2Si(CH2)3(i-Bu)6Si7O9(OH)3 (6), containing a Si-H group in one of the ligands of the silsesquioxane, was tethered onto a vinyl terminated hyperbranched poly(siloxysilane) polymer via a hydrosilation reaction to generate extremely active catalysts, P1-8 and c-P1-8. The synthesis of 6, in good yield, was accomplished via hydrosilation of CH2=CHCH2(i-Bu)7Si8O12 (1) to generate ClMe2Si(CH2)3(i-Bu)7Si8O12 …


Plasma Treated Mesoporous Tio2 Thin Films For Energy Storage Applications, Allen D. Reed Jan 2015

Plasma Treated Mesoporous Tio2 Thin Films For Energy Storage Applications, Allen D. Reed

Theses and Dissertations--Chemistry

Mesoporous TiO2 films treated with N2/argon plasma or H2 plasma were studied for use in photoelectrochemical water splitting and electrochemical supercapacitors, respectively. Cubic-ordered mesoporous thin films were prepared by a templated sol-gel method. UV-Vis absorbance spectra indicated that nitrogen plasma treatment significantly reduced the band gap of the TiO2. XPS analysis showed that nitrogen atoms are incorporated into substitutional sites, rather than interstitial. Photocatalytic activity of nitrogen-doped TiO2 films was evaluated by chronoamperometry and linear sweep voltammetry. Compared to pristine TiO2, plasma-treated films showed remarkable photocurrent enhancement (up to 240 times) …


Ferrocene-Fused Derivatives Of Acenes, Tropones And Thiepins, Bidhya L. Maharjan Jan 2015

Ferrocene-Fused Derivatives Of Acenes, Tropones And Thiepins, Bidhya L. Maharjan

Theses and Dissertations--Chemistry

This research project is concentrated on tuning the properties of small organic molecules, namely polyacenes, tropones and thiepins, by incorporating redox-active transition metal centers π-bonded to terminal cyclopentadienyl ligands. Organometallic-fused acenequinones, tropones, thiepins and cyclopentadiene-capped polyacenes were synthesized and characterized. This work was divided into three parts: first, the synthesis of ferrocene-fused acenequinones, cyclopentadiene-capped acenequinones and their subsequent aromatization to polyacenes; second, the synthesis of ferrocene-fused tropones, thiotropones and tropone oxime; and third, the synthesis of ferrocene-fused thiepins. Ferrocene-fused quinones are the precursors to our target complexes. Our synthetic route to ferrocenequinones involved two-fold aldol condensation between 1,2-diformylferrocene and naphthalene-1,4-diol …


Development Of An Extraction Method For The Mass Spectral Analysis Of Organic Gunshot Residue From Clothing, Brent Casper Jan 2015

Development Of An Extraction Method For The Mass Spectral Analysis Of Organic Gunshot Residue From Clothing, Brent Casper

Theses and Dissertations--Chemistry

This dissertation will focus on the extraction of volatile organic compounds associated with gunshot residue from articles of clothing, followed by analysis with mass spectrometry. During the discharge of a weapon, a cloud of volatile organic gunshot residue (OGSR) is dispersed around a firearm. This will create a high probability of transfer between the OGSR and the clothing of individuals who are near a discharged weapon.

The first part of this dissertation will be the development of a method for removal of volatile OGSR from articles of clothing. Extraction of OGSR will be completed by solid phase microextraction (SPME), followed …


Inhalable Nanocomposites And Anticancer Agents For Cancer Therapy, Nathanael A. Stocke Jan 2015

Inhalable Nanocomposites And Anticancer Agents For Cancer Therapy, Nathanael A. Stocke

Theses and Dissertations--Chemical and Materials Engineering

Cancer is designated as the leading cause of mortality worldwide and lung cancer is responsible for nearly 30% of all cancer related deaths. Over the last few decades mortality rates have only marginally increased and rates of recurrence remain high. These factors, among others, suggest the need for more innovative treatment modalities in lung cancer therapy. Targeted pulmonary delivery is well established for treating pulmonary diseases such as asthma and provides a promising platform for lung cancer therapy. Increasing local deposition of anticancer agents (ACAs) and reducing systemic exposure of these toxic moieties could lead to better therapeutic outcomes and …