Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 7081 - 7110 of 10873

Full-Text Articles in Entire DC Network

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 (1977-2023)

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 …

Go to article

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 (1977-2023)

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 …

Go to article

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 (1977-2023)

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 …

Go to article

Socio-Cultural Factors Challenging Development Interventions In Cattle Production In The Remote Areas Of Vietnam, Duong-Nam Ha, Pham-Van Hung, Tran-The Cuong, Ninh-Xuan Trung, Tran-Van Long, Laurie Bonney, Peter A. Lane, Guillaume Duteurtre, Stephen Ives Jan 2015

Socio-Cultural Factors Challenging Development Interventions In Cattle Production In The Remote Areas Of Vietnam, Duong-Nam Ha, Pham-Van Hung, Tran-The Cuong, Ninh-Xuan Trung, Tran-Van Long, Laurie Bonney, Peter A. Lane, Guillaume Duteurtre, Stephen Ives

IGC Proceedings (1977-2023)

The northwest highlands of Vietnam are characterized by high altitude, low infrastructure, and low population densities composed of a wide diversity of different ethnic groups. Their socio-cultural characteristics strongly influence their lifestyle and production systems, including agricultural activities. The majority of these people have suffered from slow economic development, with the highest poverty rate in the country. This is a real need for plausible interventions where behavioral changes of smallholders throughout local value chains would be a critical foundation. Our project implemented in this context of development in the Northwest highlands of Vietnam aims to understand the role of socio-cultural …

Go to article

Conservation Of Grassland Plant Genetic Resources Through People Participation, D. R. Malaviya, Ajoy K. Roy, P. Kaushal Jan 2015

Conservation Of Grassland Plant Genetic Resources Through People Participation, D. R. Malaviya, Ajoy K. Roy, P. Kaushal

IGC Proceedings (1977-2023)

Agrobiodiversity provides the foundation of all food and feed production. Hence, need of the time is to collect, evaluate and utilize the biodiversity globally available. Indian sub-continent is one of the world’s mega centers of crop origins. India possesses 166 species of agri-horticultural crops and 324 species of wild relatives. India is reported to have five grass covers identified. There have been almost nil human interference in terms of selection pressure; hence, the biodiversity is well conserved in these grazing lands. There is need of a system approach to understanding biodiversity that moves significantly beyond taxonomy and species observations. In …

Go to article

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 (1977-2023)

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 …

Go to article

Front Matter [23rd International Grassland Congress Proceedings], National Organizing Committee, International Grassland Congress Jan 2015

Front Matter [23rd International Grassland Congress Proceedings], National Organizing Committee, International Grassland Congress

IGC Proceedings (1977-2023)

No abstract provided.

Go to article

In Vitro Study Of Wound-Healing Capabilities Of Bioactive Glass Fibers Under Various Culture Conditions, Sisi Chen Jan 2015

In Vitro Study Of Wound-Healing Capabilities Of Bioactive Glass Fibers Under Various Culture Conditions, Sisi Chen

Masters Theses

"Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying physiological and cellular mechanism behind this function remains unclear. In this study, in vitro dynamic flow modules were designed to mimic the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, and were used to investigate the biocompatibility and functionality of borate glass nano-/micro-fibers. Glass-cell interactions were investigated either by dosing fibers to the upstream of or co-cultured with cells, and two types of borate glasses (with or without CuO/ZnO doped were …

Go to article

Exponentially Increasing Incidences Of Cutaneous Malignant Melanoma In Europe Correlate With Low Personal Annual Uv Doses And Suggests 2 Major Risk Factors, Stephen Merrill, Samira Ashrafi, Madhan Subramanian, Dianne E. Godar Jan 2015

Exponentially Increasing Incidences Of Cutaneous Malignant Melanoma In Europe Correlate With Low Personal Annual Uv Doses And Suggests 2 Major Risk Factors, Stephen Merrill, Samira Ashrafi, Madhan Subramanian, Dianne E. Godar

Mathematics, Statistics and Computer Science Faculty Research and Publications

For several decades the incidence of cutaneous malignant melanoma (CMM) steadily increased in fair-skinned, indoor-working people around the world. Scientists think poor tanning ability resulting in sunburns initiate CMM, but they do not understand why the incidence continues to increase despite the increased use of sunscreens and formulations offering more protection. This paradox, along with lower incidences of CMM in outdoor workers, although they have significantly higher annual UV doses than indoor workers have, perplexes scientists. We found a temporal exponential increase in the CMM incidence indicating second-order reaction kinetics revealing the existence of 2 major risk factors. From epidemiology …

Go to article

Gvsu Sustainable Agriculture Project Handbook, Youssef Darwich, Dana Eardley Jan 2015

Gvsu Sustainable Agriculture Project Handbook, Youssef Darwich, Dana Eardley

Honors Projects

The GVSU Sustainable Agriculture Project was started by a group of Grand Valley students in 2008, and is a project of the Brooks College of Interdisciplinary Studies. The original farm site is on Luce Street on the Allendale campus.

Go to article

Comparison Of Blood Lead Levels Between Children In An Urban Setting And Children In A Rural Setting, Juan Manuel Alvarez Jan 2015

Comparison Of Blood Lead Levels Between Children In An Urban Setting And Children In A Rural Setting, Juan Manuel Alvarez

Open Access Theses & Dissertations

Environmental heavy metal exposure is a public health problem that is of great concern because it is highly toxic for children. The urban setting in downtown El Paso is historically known to be contaminated through various sources of contamination of heavy metals. The goal of this study was to compare whether children in a historically contaminated urban downtown area had significantly increased levels of lead exposure as compared to children in a demographically similar rural area approximately 20 miles north of the urban center, while controlling for gender and age. Cadmium and mercury were also measured for comparison purposes. It …

Go to article

A Pilot Study Of Arsenic In Young Children From Two Rural West Texas Communities: Blood Levels, Household Water Levels, And Behavioral Outcomes, Michelle Del Rio Jan 2015

A Pilot Study Of Arsenic In Young Children From Two Rural West Texas Communities: Blood Levels, Household Water Levels, And Behavioral Outcomes, Michelle Del Rio

Open Access Theses & Dissertations

Background & Significance: Heavy metals have been identified as a child health hazard because children are highly vulnerable to the effects of exposure, which can be physical, cognitive, and behavioral. Levels of arsenic (As) greater than the EPA Maximum Contaminant Level (10μg/L) were identified in some household water samples in two rural west Texas communities located within 20 miles of the U.S.-Mexico border by a Health Impact Assessment conducted in 2013 (Hargrove, Juarez-Carillo, & Korc 2015). Whether home water samples predicted child blood As levels needed to be examined. Since lead (Pb) is another common heavy metal contaminant in the …

Go to article

Nanoceria Exposure To Kidney Beans (Phaseolus Vulgaris): Implications On Plant Physiology, Nutrition And Their Transfer To Next Trophic Level, Sanghamitra Majumdar Jan 2015

Nanoceria Exposure To Kidney Beans (Phaseolus Vulgaris): Implications On Plant Physiology, Nutrition And Their Transfer To Next Trophic Level, Sanghamitra Majumdar

Open Access Theses & Dissertations

Previous studies investigating the effects of cerium oxide nanoparticles (nanoceria, nCeO2) on plants have primarily focused on the physiological and biochemical changes at early growth stages. Comprehensive information on the effects of nCeO2 through the entire life cycle of plants and the nutritional quality of the edible tissues is limited. No studies have been reported on the interactions between nCeO2 and common beans (Phaseolus vulgaris). Common beans are leguminous crops, which are societally important due to their nutritional benefits. The beans are rich in proteins and essential nutrients like folate, iron, zinc, molybdenum and magnesium, and are consumed worldwide. This …

Go to article

Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann Jan 2015

Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann

CCPO Publications

We propose definitions in terminology to enhance ongoing collaborations between biologists and modellers on plankton ecology. Organism "functional type" should refer to commonality in ecology not biogeochemistry; the latter is largely an emergent property of the former, while alignment with ecology is also consistent with usage in terrestrial science. Adaptation should be confined, as in genetics, to consideration of species inter-generational change; most so-called "adaptive" plankton models are thus acclimative, modifying vital rates in response to stimuli. Trait trade-off approaches should ideally only be considered for describing intra-generational interactions; in applications between generations, and certainly between unrelated species, such concepts …

Go to article

The Effect Of Parental Size On Spermatophore Production, Egg Quality, Fertilization Success, And Larval Characteristics In The Caribbean Spiny Lobster, Panulirus Argus, Mark J. Butler Iv, Alison Macdiarmid, Gaya Gnanalingam Jan 2015

The Effect Of Parental Size On Spermatophore Production, Egg Quality, Fertilization Success, And Larval Characteristics In The Caribbean Spiny Lobster, Panulirus Argus, Mark J. Butler Iv, Alison Macdiarmid, Gaya Gnanalingam

Biological Sciences Faculty Publications

The average size of spiny lobsters (Decapoda; Palinuridae) has decreased worldwide over the past few decades. Market forces coupled with minimum size limits compel fishers to target the largest individuals. Males are targeted disproportionately as a consequence of sexual dimorphism in spiny lobster size (i.e. males grow larger than females) and because of protections for ovigerous females. Therefore, overexploitation of males has led to sperm limitation in several decapod populations with serious repercussions for reproductive success. In the Caribbean spiny lobster, Panulirus argus, little is known about the effect of reduced male size on fertilization success or the role …

Go to article

Survey Of Two Perfluorinated Organic Compounds (Pfoa And Pfhxa) In Water And Biota Surrounding A Polyfluorinated Chemical Plant, Kevin S. Dillon Jan 2015

Survey Of Two Perfluorinated Organic Compounds (Pfoa And Pfhxa) In Water And Biota Surrounding A Polyfluorinated Chemical Plant, Kevin S. Dillon

Gulf and Caribbean Research

Perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA) concentrations were measured in water and biota samples collected within and near a polyfluorinated chemical plant in coastal Mississippi. Effluents from the site and from the local public water treatment plant were sampled along with municipal water supplies, shallow groundwater beneath the site, nearby surface waters, and local biota. Highest concentrations were from stormwater ([PFOA] = 85—530 ng/l; PFHxA = 140—590 ng/l) and shallow groundwaters ([PFOA] = 44—1000 ng/l; PFHxA = 210—3100 ng/l) collected at the site. The local public water treatment effluent also had relatively high PFHxA concentrations (310—590 ng/l). Intermediate PFOA …

Go to article

Modeling The Dynamic Processes Of Challenge And Recovery (Stress And Strain) Over Time, Fan Yang Jan 2015

Modeling The Dynamic Processes Of Challenge And Recovery (Stress And Strain) Over Time, Fan Yang

Department of Statistics: Dissertations, Theses, and Student Research

A dynamic process with challenge and recovery is an important branch in the family of stochastic processes. The dependent data of such processes are often observed over time, and hence, are time dependent. The purpose of this dissertation is to develop methods to characterize a dynamic process with challenge and recovery under different dimensionalities and error assumptions. In this dissertation, a univariate dynamic process under Gaussian assumption is discussed first and a bi-logistic model is developed by three different methods: compartment, additive, and Bayesian. Then the discussion is extended to a bivariate hysteresis system with challenge and recovery. Three methods: …

Go to article

Spatial Incidence Of Adult Obesity In The State Of Alabama, Mary G. Odhiambo Jan 2015

Spatial Incidence Of Adult Obesity In The State Of Alabama, Mary G. Odhiambo

Theses

No abstract provided.

Go to article

Developments In Nonparametric Regression Methods With Application To Raman Spectroscopy Analysis, Jing Guo Jan 2015

Developments In Nonparametric Regression Methods With Application To Raman Spectroscopy Analysis, Jing Guo

Theses and Dissertations--Epidemiology and Biostatistics

Raman spectroscopy has been successfully employed in the classification of breast pathologies involving basis spectra for chemical constituents of breast tissue and resulted in high sensitivity (94%) and specificity (96%) (Haka et al, 2005). Motivated by recent developments in nonparametric regression, in this work, we adapt stacking, boosting, and dynamic ensemble learning into a nonparametric regression framework with application to Raman spectroscopy analysis for breast cancer diagnosis. In Chapter 2, we apply compound estimation (Charnigo and Srinivasan, 2011) in Raman spectra analysis to classify normal, benign, and malignant breast tissue. We explore both the spectra profiles and their derivatives to …

Go to article

University Of North Florida Environmental Center Annual Report 2015, Caitlin Kengle, James W. Taylor Jan 2015

University Of North Florida Environmental Center Annual Report 2015, Caitlin Kengle, James W. Taylor

Annual Reports

2015 Annual Report of the Environmental Center at the University of North Florida

Go to article

Get Two For One—The Same Strategies Help You Go Green And Improve Wellness, Jean S. Waters Jan 2015

Get Two For One—The Same Strategies Help You Go Green And Improve Wellness, Jean S. Waters

White Papers

Going green and losing weight may very well be two of the biggest ever lifestyle buzzwords. Both require conscious effort, planning and systematic changes and both yield beneficial results. Drawing comparisons between green and wellness campaigns, Jean Waters, environmental engineer, discusses costs, benefits and strategies of pursuing sustainability.

Go to article

Mind-Craft: Exploring The Relation Between "Digital" Visual Experience And Orientation In Visual Contour Perception, Daniel Hipp Jan 2015

Mind-Craft: Exploring The Relation Between "Digital" Visual Experience And Orientation In Visual Contour Perception, Daniel Hipp

Graduate Dissertations and Theses

Visual perception depends fundamentally on statistical regularities in the environment to make sense of the world. One such regularity is the orientation anisotropy typical of natural scenes; most natural scenes contain slightly more horizontal and vertical information than oblique information. This property is likely a primary cause of the “oblique effect” in visual perception, in which subjects experience greater perceptual fluently with horizontally and vertically oriented content than oblique. However, recent changes in the visual environment, including the “carpentered” content in urban scenes and the framed, caricatured content in digital screen media presentations, may have altered the level of orientation …

Go to article

Identification Of Interactions Between Lhx2 And Other Neocortical Proteins, William Shannon Jackson Jan 2015

Identification Of Interactions Between Lhx2 And Other Neocortical Proteins, William Shannon Jackson

All Master's Theses

Lhx2 is a protein that is expressed in a gradient across the developing neocortex and is involved in arealization, the process through which this structure is divided into functional fields. However, little is known on how Lhx2's graded expression across the neocortex actually regulates the locations and sizes of the neocortical areas. In an attempt to understand how Lhx2 performs its functions within the neocortex, a yeast two-hybrid screen was used to identify possible binding partners for Lhx2. Of the sixteen pulled from the screen, two proteins, Eri3 and Ddx50, were deemed as having the highest likelihood of playing a …

Go to article

Interpretation Of Shell [Delta]180 And [Delta]13c From Two Hells Canyon Study Sites: A Methods Approach To Analysis, Nathaniel Jacob Morse Jan 2015

Interpretation Of Shell [Delta]180 And [Delta]13c From Two Hells Canyon Study Sites: A Methods Approach To Analysis, Nathaniel Jacob Morse

All Master's Theses

I analyze stable oxygen isotope ([delta]180) and stable carbon isotope ([delta]13C) data from shell at two study sites in the Hells Canyon in Oregon and Idaho. Mussel shell isotope data from two species, Margaritifera falcata and Gonidea angulata, are compared with a terrestrial snail species Oreohelix strigosa from the Tryon Creek site (35WA288) and the Bernard Creek Rockshelter (1 0IH483). There were five methodological hypotheses to test with these data. Three tests yielded no significant correlation in isotope values: M falcata vs. G. angulata, mussels vs. snails, and winter vs. summer increments of snails. A fourth test showed …

Go to article

Front Matter [Preface And List Of Contributors], National Organizing Committee, International Grassland Congress Jan 2015

Front Matter [Preface And List Of Contributors], National Organizing Committee, International Grassland Congress

IGC Proceedings (1977-2023)

No abstract provided.

Go to article

Promising Forage Options To Enhance Livestock Production In Mediterranean Climate Agricultural Systems, Serkan Ates, Hayley C. Norman, Hichem Ben Salem, Bradley Nutt, Harun Cicek Jan 2015

Promising Forage Options To Enhance Livestock Production In Mediterranean Climate Agricultural Systems, Serkan Ates, Hayley C. Norman, Hichem Ben Salem, Bradley Nutt, Harun Cicek

IGC Proceedings (1977-2023)

The increasing demand for food, fibre and animal products inevitably requires intensifying agricultural production worldwide. This can present a number of environmental and farming systems challenges in Mediterranean climate areas of the world. Developments of novel strategies, employing ecologically sound intensification practices, are crucial to enhance production in the Mediterranean agropastoral production systems. In this paper, we have discussed forage based systems that improve productivity, profitability, environmental quality and resilience of the farming systems. Key opportunities include better use and integration of diverse genetic resources, new agronomic techniques and the utilization of perennial forage plants that are adapted to land …

Go to article

Grazing Management Options For Maintaining Optimum Pasture Composition And Utilization, Glen E. Aiken Jan 2015

Grazing Management Options For Maintaining Optimum Pasture Composition And Utilization, Glen E. Aiken

IGC Proceedings (1977-2023)

Global demand for meat and dairy products will continue to increase over the 21st century, however, the global forage-based livestock industry will be challenged in meeting production goals with minimal impact of the environment. Sustainable production of grazing livestock will depend on the use of carefully planned grazing management strategies. Development of a grazing management plan involves making two decisions: determining the livestock density at which pastures are stocked and settling on the method used to graze the pastures. Stocking rate indirectly affects output per animal and per hectare through its direct effect on forage mass and pasture composition. A …

Go to article

Management Of Pasture Soils: Biochar Stability, Carbon Storage Potential And Its Effect On Production And Quality, Bhupinder Pal Singh, Yunying Fang, Mark Boersma, Damian Collins, Lukas Van Zwieten, Lynne M. Macdonald Jan 2015

Management Of Pasture Soils: Biochar Stability, Carbon Storage Potential And Its Effect On Production And Quality, Bhupinder Pal Singh, Yunying Fang, Mark Boersma, Damian Collins, Lukas Van Zwieten, Lynne M. Macdonald

IGC Proceedings (1977-2023)

The use of biochar has been proposed as a stable carbon (C) amendment with long-term carbon (C) storage potential in agricultural soils while improving primary productivity. However, this concept has not been widely tested in contrasting soils under temperate pasture systems. To address this knowledge gap, a 13C-labelled biochar, produced from Eucalyptus saligna biomass by slow pyrolysis (450° C; d13C -36.7‰) was surface (0"10 cm) applied in C3 dominated, annual temperate pasture systems across Arenosol, Cambisol and Ferralsol. The results show that only 2% of the applied biochar-C was mineralised in a relatively clay- and C-poor …

Go to article

Grassland Renovation And Consequences For Nutrient Management, Johannes Isselstein, Manfred Kayser Jan 2015

Grassland Renovation And Consequences For Nutrient Management, Johannes Isselstein, Manfred Kayser

IGC Proceedings (1977-2023)

Sward degradation is a serious threat to the functioning of grassland and the provision of ecosystem services. Renovation measures are frequently applied in order to restore degraded swards. However, the success is highly variable and substantial tradeoffs are often found following renovation such as among agronomic and environmental services. Starting from a general classification of renovation measures the paper investigates the processes induced by renovation that lead to a change of the vegetation and that affect carbon and nitrogen fluxes. These processes are strongly interrelated and dependent on site, climate and management condition as well as on the time scale. …

Go to article

Math In The Modern World, Steven Cosares Jan 2015

Math In The Modern World, Steven Cosares

Open Educational Resources

Students are asked to gather nutrition data regarding their favorite snacks and assess how well they contribute to their maintenance of a “healthy” diet, as defined through, articles, websites, and guidelines established by the US Department of Agriculture.

Go to article

First Prev Next Last