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New Generation Of Electrochemical Sensors For Nitric Oxide;Ruthenium/Carbon-Based Nanostructures And Colloids As Electrocatalytic Platforms, W. Pubudu M. Peiris

ETD Archive

Nitric oxide (NO) is an important intercellular messenger that acts in many tissues to regulate a diverse range of physiological and pathological processes. The physiologically implications of NO function are far from being completely understood. The multifaceted reactivity of NO prompted the need for accurate determination of the concentration of this molecule. However, it is difficult to detect nitric oxide, particularly in biological media and near live cells due to its short half-life, a result of its reactivity and the low levels of NO produced in vivo. As a result, the accurate and reliable detection of NO under varying experimental …

Nitrogen Removal And Sustainability Of Vertical Flow Constructed Wetlands For Small Scale Wastewater Treatment, Valerie J. Fuchs

Dissertations, Master's Theses and Master's Reports - Open

The challenge for wastewater professionals is to design and operate treatment processes that support human well being and are environmentally sensitive throughout the life-cycle. This research focuses on one technology for small-scale wastewater treatment: the vertical flow constructed wetland (VFCW), which is herein investigated for the capacity to remove ammonium and nitrate nitrogen from wastewater. Hydraulic regime and presence/absence of vegetation are the basis for a three-phase bench scale experiment to determine oxygen transfer and nitrogen fate in VFCWs. Results show that 90% NH4+-N removal is achieved in aerobic downflow columns, 60% NO3--N removal occurs in anaerobic upflow columns, and …

Effects Of Variation In Plant Quality On Densities And Sizes Of Herbivores, Primary And Secondary Parasitoids, Xavier M. Chiriboga

All PhD Dissertations

To investigate the effects of variation in host quality on densities and sizes of three levels of consumers, a cabbage-aphid-parasitoid foodweb was analyzed. Three close related cabbage populations were studied: Brassica oleracea var. gemnifera cv. Cyrus, a feral Brassica oleracea and a wild cabbage type Old Harry as source of variation in host plant quality. A field experiment were established in Wageningen, The Netherlands to measure the effects on densities of herbivores. Aphids and lepidopteran species were monitored weekly during eight weeks on fifteen randomized plants within each plot. Parasitism in aphids and numbers of predators (coccinelids and syrphids) were …

Gene Pool Organization, Population Genetics And Wild-Crop Complex Dynamics Of Cowpea (Vigna Unguiculata), Eric Bertrand Kouam

All PhD Dissertations

Cowpea is a tropical legume contributing significantly to food security in developing countries, especially in Africa. This research project was motivated by the upcoming introduction of Bt cowpea in Africa, likely to disturb the genetic equilibrium existing between wild and cultivated cowpea. The objectives of this study were to assess the genetic relationship between wild and cultivated cowpea, to determine how inbred and how differentiated are cowpea populations as well as gene flow, to estimate the mating system parameters in cowpea and their relation to ecological agents. In order to achieve these goals, wild and cultivated cowpea individuals were electrophoreticafy …

Diversity And Ecological Preference Of Parasitoids Associated With Lepidopteran Stem Borers In Kenya, Duna Madu Mailafiya

All PhD Dissertations

Field surveys were carried out from 2005 to 2007 to assess parasitoid species diversity and stem borer parasitism in cultivated and natural habitats in four agroecological zones in Kenya. To increase the chances of collecting stem borer parasitoids, random sampling was employed in cultivated habitats, while both random and non-random samplings were applied in natural habitats. A total of 7443 and 3676 stem borers were collected from cultivated and natural habitats, respectively. Thirty-three species of parasitoid were recovered. Eighteen of them from six stem borer species feeding on cereal crops, and twenty seven from twenty-one stem borer species feeding on …

Basis Of Host Recognition By The Larval Endoparasitoids: Cotesia Sesamiae Cameron And Cotesia Flavipes (Cameron) (Hymenoptera: Braconidae), Amos Owino Meshack Obonyo

All PhD Dissertations

Host recognition behaviour of two braconid larval parasitoids Cotesia sesamiae and Cotesia flavipes was studied using suitable stemborer hosts [i.e. Busseola fusca for C. sesamiae, and Chilo partellus for C. flavipes] and one non-host [Eldana saccharina]. The wasps displayed similar sequences of behavioural steps when locating their hosts largely depending on their antennae for host recognition and both antennae and tarsi for final host acceptance and oviposition. Tactile and contact chemoreception stimuli from the hosts seem to play a major role in oviposition decision by the parasitoids. In addition, the external morphology and distribution pattern of sensilla present on antennae, …

Reproductive Isolation Between Two Sympatric Simultaneous Hermaphroditic Shrimp, Lysmata Wurdemanni And L. Boggessi, Dong Zhang, Junda Lin, Jörg D. Hardege, Andrew L. Rhyne

Arts & Sciences Faculty Publications

To investigate pre- and post-zygotic isolation between two sympatric and phylogenetically related species of Lysmata shrimp, two assays were conducted in the laboratory: (1) no specific mate choice where mating between the two species was ‘forced’; (2) specific mate choice or preference where a female had a choice between conspecific and heterospecifc males. Behavioural studies reveal that female L. wurdemanni accepted only conspecific male shrimp, whereas L. boggessi females would mate with an interspecific male if there was no conspecific male present. When males of both species were present, L. boggessi females always mated with the conspecific male. Male L. …

Development Of Formulations And Delivery Systems To Control Economically Important Ticks With Entomopathogenic Fungi, Felix Nchu

All PhD Dissertations

Due to the rapid development of tick resistance to synthetic chemical acaricides and the potential risk posed by these chemicals to non-target species, efforts are intensifying towards the development of entomopathogenic fungi as an environmentally benign alternative tick control strategy. The main objective of this study is the development of formulations and delivery systems for control of ticks with entomopathogenic fungi. Screening of entomopathogenic fungal isolates is the first step towards the development of mycoacaricides. Twelve isolates of Metarhizium anisopliae (Metschnik.) Sorok. and three isolates of Beauveria bassiana (Bals.) Vuill. (Ascomycota: Hypocreales) were evaluated for pathogenicity against unfed Rhipicephalus pulchellus …

Identification Of Chemical Signals That Influence The Oviposition Behaviour Of Anopheles Gambiae And Exploration Of Their Potential In Mosquito Control, Sabina Wangui Wachira

All PhD Dissertations

The African mosquito species Anopheles gambiae and An. funestus are ranked high among the world's most efficient vectors of human malaria. Their juvenile stages develop in aquatic environments while adults are terrestrial. Chemical signals guide gravid females of these vectors to their egg-laying sites. Several attributes of a pond including presence of other organisms influence egg hatching success and larval survival. Gravid An. gambiae females strongly discriminate among potential egg-laying sites to ensure viability of their offsprings. This study is based on the hypothesis that gravid An. gambiae females use chemical cues from microbial activity and/or those associated with competitors …

Ethnobotanicals For Management Of The Brown Ear Tick Rhipicephalus Appendiculatus In Western Kenya, Wycliffe Wanzala

All PhD Dissertations

This thesis describes the results of a study to assess the effect of ethnobotanical products on the behaviour of the brown ear tick Rhipicephalus appendiculatus, the main vector of East Coast fever in sub-Saharan Africa. Ethnoknowledge of the Bukusu people in western Kenya on tick control and management was evaluated to identify plants that affect livestock ticks, using participatory action research approaches. More than 150 plant species spread over 110 genera and 51 families were identified and documented. From these, eight plants were selected and their essential oils extracted and used for screening in the laboratory on their behavioural effects …

An Evaluation Of The Effects Of Information And Technology Characteristics On Technology Choice And Adoption The Case Of Striga And Stemborer Control Technologies In Maize Production In Western Kenya, Esther Njuguna Mwihaki

All PhD Dissertations

Kenya's population is increasing, thus leading to increased demand for food, especially maize which is a staple food for most of the Kenyan population. Demand for maize in Sub Saharan Africa is projected to double to 52 million tons by 2020 (Pingali and Pandey). The increasing population has also caused the per capita farm holdings in Kenya rural areas to become smaller due to continuous sub-division. Besides the reduced farm holding, maize production is constrained by both biotic and abiotic factors. Two of the most important biotic constraints in maize production are Striga and stemborer infestations.Maize yield loss due to …

The Biology And Ecology Of Mussidia Spp. (Lepidoptera: Pyralidae) And Associated Natural Enemies In Kenya., Benjamin Kimwele Muli

All PhD Dissertations

Mussidia nigrivenella Ragonot (Lepidoptera: Pyralidae), an important pest of maize, cotton and Phaseolus bean in West Africa, has never been described as a crop pest from East and southern Africa (ESA). It was hypothesized that in ESA it was either kept under control by natural enemies or that there exist several populations of M. nigrivenella with different host plant ranges. Another possibility is the mis-identification of the Mussidia species in ESA. Studies were conducted in Kenya between 2005 and 2007 to assess the species diversity and host plant range of Mussidia spp. and spatial distribution studies were done on selected …

General Undergraduate Catalog, 2009-2010, Marshall University

Marshall University Catalogs 2000-2009

Marshall University Undergraduate Catalog for the 2009-2010 academic year.

Graduate Catalog, Spring 2009, Marshall University

Marshall University Catalogs 2000-2009

Marshall University Graduate Catalog for the Spring 2009 academic semester.

Graduate Catalog, Fall 2009, Marshall University

Marshall University Catalogs 2000-2009

Marshall University Graduate Catalog for the Fall 2009 academic year.

Light-Induced Fos Expression In Intrinsically Photosensitive Retinal Ganglion Cells In Melanopsin Knockout (Opn4-/-) Mice, Gary E. Pickard, Scott B. Baver, Malcolm D. Ogilvie, Patricia J. Sollars

School of Veterinary and Biomedical Sciences: Faculty Publications

Retinal ganglion cells that express the photopigment melanopsin are intrinsically photosensitive (ipRGCs) and exhibit robust synaptically driven ON-responses to light, yet they will continue to depolarize in response to light when all synaptic input from rod and cone photoreceptors is removed. The light-evoked increase in firing of classical ganglion cells is determined by synaptic input from ON-bipolar cells in the proximal sublamina of the inner plexiform layer. OFF-bipolar cells synapse with ganglion cell dendrites in the distal sublamina of the inner plexiform layer. Of the several types of ipRGC that have been described, M1 ipRGCs send dendrites exclusively into the …

Piñon And Juniper Field Guide: Asking The Right Questions To Select Appropriate Management Actions, Robin J. Tausch, R. F. Miller, B. A. Roundy, J. C. Chambers

Reports

Piñon-juniper woodlands are an important vegetation type in the Great Basin. Old-growth and open shrub savanna woodlands have been present over much of the last several hundred years. Strong evidence indicates these woodlands have experienced significant tree infilling and major expansion in their distribution since the late 1800s by encroaching into surrounding landscapes once dominated by shrubs and herbaceous vegetation. Both infilling and expansion affects soil resources, plant community structure and composition, water and nutrient cycles, forage production, wildlife habitat, biodiversity, and fire patterns across the landscape. Another impact is the shift from historic fire regimes to larger and more …

Western Michigan University Graduate Catalog 2009-2010, Western Michigan University

Western Michigan University Course Catalogs (1904-present)

• General Information
• Colleges
• Course Descriptions (by College)

Western Michigan University Undergraduate Catalog 2009-2010, Western Michigan University

Western Michigan University Course Catalogs (1904-present)

• General Information
• Colleges
• Course Descriptions (by prefix)

Measuring Turbulent Large-Eddy Structures With An Adcp. Part 2. Horizontal Velocity Variance, A. E. Gargett, A. E. Tejada-Martínez, C. E. Grosch

Journal of Marine Research

This paper considers the degree of accuracy with which observations from an acoustic Doppler current profiler (ADCP) can determine turbulent horizontal velocity variance. As in a previous paper addressing turbulent vertical velocity variance, we use a combination of techniques, deriving response functions from simple theory and from oceanic observations taken with a VADCP (an ADCP with an additional vertical (V) beam) in two different oceanic turbulent flows, Langmuir supercells (LSC) and unstable convection. In the case of LSC, we also determine response by sampling available Large-Eddy Simulations (LES) with specified beam geometry. In contrast with the previous investigation, where a …

Sensitivity Of Plankton Biomass And Productivity To Variations In Physical Forcing And Biological Parameters In Chesapeake Bay, Ming Li, Liejun Zhong, Lawrence W. Harding Jr.

Journal of Marine Research

A coupled three-dimensional hydrodynamic-biogeochemical model is used to simulate plankton dynamics in Chesapeake Bay and examine its sensitivity to variations in biological parameters and physical forcing. The coupled biophysical model captures observed seasonal cycle and regional distributions of plankton in Chesapeake Bay and predicts the "phase lag" between the spring chlorophyll maximum and the summer primary productivity maximum. This lag traces to the delivery of dissolved inorganic nutrients in the winter-spring freshet from the Susquehanna River that fuels the spring bloom, whereas regenerated nutrients support high primary productivity in summer. The model shows that episodic wind events commonly associated with …

A Shallow Water Model Conserving Energy And Potential Enstrophy In The Presence Of Boundaries, Rick Salmon

Journal of Marine Research

We extend a previously developed method for constructing shallow water models that conserve energy and potential enstrophy to the case of flow bounded by rigid walls. This allows the method to be applied to ocean models. Our procedure splits the dynamics into a set of prognostic equations for variables (vorticity, divergence, and depth) chosen for their relation to the Casimir invariants of mass, circulation and potential enstrophy, and a set of diagnostic equations for variables that are the functional derivatives of the Hamiltonian with respect to the chosen prognostic variables. The form of the energy determines the form of the …

Children Of Foster Care: Elevating Their Voices, Nancy A. Cristadoro

Regis University Student Publications (comprehensive collection)

The purpose of this paper was to discuss how through research and an internship with Douglas County Child Welfare, elevating children"â„¢s voices in decisions of placement is a vital component of child welfare reform today. This paper examines some of the negative outcomes of the foster care system on children who age out of the system. The negative impact further deteriorates children"â„¢s self esteem and increases the occurrence of homelessness and incarceration in our society. The internship further validated the difficulty inherent in including children in decisions of placements and the importance of allowing extra time, planning and changing mind …

Marchagee Oil Mallee Study : Drill Completion And Preliminary Hydrogeological Report, D L. Bennett, Adrian Goodreid

Resource management technical reports

No abstract provided.

Antioxidant And Anticancer Activities Of Wampee (Clausena Lansium (Lour.) Skeels) Peel, K. Nagendra Prasad, Jing Hao, Chun Yi, Dandan Zhang, Shengxiang Qiu, Yueming Jiang, Mingwei Zhang, Feng Chen

Publications

Antioxidant activities of wampee peel extracts using five different solvents (ethanol, hexane, ethyl acetate, butanol and water) were determined by using in-vitro antioxidant models including total antioxidant capability, 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, reducing power, and superoxide scavenging activity. Ethyl acetate fraction (EAF) exhibited the highest antioxidant activity compared to other fractions, even higher than synthetic antioxidant butylated hydroxyl toluene (BHT). In addition, the EAF exhibited strong anticancer activities against human gastric carcinoma (SGC-7901), human hepatocellular liver carcinoma (HepG-2) and human lung adenocarcinoma (A-549) cancer cell lines, higher than cisplatin, a conventional anticancer drug. The total phenolic content of …

Nimbus (Winter 2009), New College Alumnae/I Association

Alumnae/i Association Collection

No abstract provided.

Guide For Quantifying Fuels In The Sagebrush Steppe And Juniper Woodlands Of The Great Basin, Andrea Stebleton, Stephen Bunting

Reports

Prescribed fire is increasingly used for fuels management and ecosystem restoration. Managers and fuels specialists of the Great Basin are often required to estimate fuel loadings to predict fire behavior, recommend fuel treatments, or restore an area to its natural fire regime. Because of invasive species and woodland encroachment, there have been extensive changes in the fire regimes of sagebrush steppe over the past 150 years. After two years of pre-treatment sampling across six states of the Great Basin, the Sagebrush Steppe Treatment and Evaluation Project (SageSTEP) measured many variables including vegetation, soils, hydrology, wildlife, and fuels. These data will …

Ua94/6/1 Student / Alumni Personal Papers Western Kentucky University Small Collections, Wku Archives

WKU Archives Collection Inventories

Small collections of personal papers and oral histories relating to the Western Kentucky University.

Who Owns This Text?: Plagiarism, Authorship, And Disciplinary Cultures, Carol Petersen Haviland, Joan A. Mullin

All USU Press Publications

Carol Haviland, Joan Mullin, and their collaborators report on a three-year interdisciplinary interview project on the subject of plagiarism, authorship, and "property," and how these are conceived across different fields. The study investigated seven different academic fields to discover disciplinary conceptions of what types of scholarly production count as "owned." Less a research report than a conversation, the book offers a wide range of ideas, and the chapters here will provoke discussion on scholarly practice relating to intellectual property, plagiarism, and authorship---and to how these matters are conveyed to students. Although these authors find a good deal of consensus in …

The Falcon 2009-2010, Seattle Pacific University

Seattle Pacific Student Newspapers

No abstract provided.