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Full-Text Articles in Life Sciences

The Dynamics, Distribution, And Activity Of Viruses In Lake Erie, Amanda Dean Dec 2004

The Dynamics, Distribution, And Activity Of Viruses In Lake Erie, Amanda Dean

Masters Theses

As viruses-- specifically pervasive pathogens of aquatic microorganisms-- are now included in most studies of aquatic food webs and nutrient cycles, presented here is new information from samples collected in July 2003 which demonstrates that bacteria lysed by viruses released 122 - 1080 nM of phosphorus per day throughout Lake Erie, implying that viruses acted as a major mechanism of phosphorus recycling in the lake. Viruses have been shown to be ubiquitous throughout Lake Erie, with a weak correlation between their distribution and the distribution of bacteria. Moreover, evidence suggests that virus production rates are tightly tied to the growth …


Physicochemical And Antimicrobial Properties Of Antimicrobials Encapsulated In Surfactant-Based Nanoparticles, Sylvia Gaysinksy Segura Dec 2004

Physicochemical And Antimicrobial Properties Of Antimicrobials Encapsulated In Surfactant-Based Nanoparticles, Sylvia Gaysinksy Segura

Masters Theses

Phytophenols, components of essential oil extracts, are antimicrobials that may inhibit the growth of foodborne pathogens. However, their antimicrobial activity in food systems is low because of low water solubility and association with other food components. Incorporation of phytophenols in nanoscale surfactant micelles may offer a potential solution to increase solubility and improve activity in food systems. The objectives of this study were to determine the stability and physicochemical and antimicrobial properties of micellar antimicrobial-surfactant systems.

Carvacrol and eugenol containing micelles were prepared by dispersing Surfynol® 485W and Surfynol® 465 in water at room temperature. Stability was determined …


Levels And Patterns Of Genetic Diversity In The Rare And Endangered Cumberland Stitchwort, Minuartia Cumberlandensis (Caryophyllaceae), Charles Thomas Winder Dec 2004

Levels And Patterns Of Genetic Diversity In The Rare And Endangered Cumberland Stitchwort, Minuartia Cumberlandensis (Caryophyllaceae), Charles Thomas Winder

Masters Theses

Sequences of a highly variable nuclear gene (G3pdh) were used to characterize genetic diversity within and among populations of the endangered rockhouse endemic, Minuartia cumberlandensis (Wofford and Kral) McNeill (Caryophyllaceae), and compared to a widespread and abundant related species, M. glabra (Michaux) McNeill. By reconstructing phylogenetic relationships among G3pdh variants (haplotypes) and observing the geographical distribution of those ordered variants, an attempt was made to gauge the effects of historical and contemporary population processes acting within the species, particularly those with potential implications for long-term conservation. Both M. cumberlandensis and M. glabra were found to have high overall …


Effect Of Resin And Wax Ratio On Osb Properties, Trairat Neimsuwan Dec 2004

Effect Of Resin And Wax Ratio On Osb Properties, Trairat Neimsuwan

Masters Theses

Oriented Strandboard (OSB) was made for construction purpose. Mat structure especially resin and wax ratio had an influence on major panel properties such as bending strength properties, stiffness properties, internal bonding, water absorption, thickness swell and so on. Thickness swell was an important property of OSB for using in construction and outdoor facilities. The purpose of this study was to investigate the effects of resin and wax ratio on OSB properties and rapidly predict OSB properties using near infrared spectroscopy. The laboratory OSB panels were fabricated as a multiple layer (three layers) mat structure including, orientation, resin types (phenol formaldehyde …


“Participation And Life Skill Development Of The Tennessee Junior Livestock Skillathon Programs, Amy Margaret Powell Dec 2004

“Participation And Life Skill Development Of The Tennessee Junior Livestock Skillathon Programs, Amy Margaret Powell

Masters Theses

This study examined the Tennessee Junior Livestock Skillathon Program and its objectives. Research was conducted to determine what motivates or deters youth participation, how youth prepare for the skillathon and life skill development in the areas of communication, critical thinking and self-confidence. A self-developed, eleven question, likert scale survey was mailed to 200 randomly selected youth that exhibited livestock in the 2003 Tennessee Junior Livestock beef, sheep or market hog shows. Fifty-two percent (112) participants responded.

Youth that participate in the skillathon do so because they want to see how much they know about their project and they felt the …


Evaluation Of Botanical Oil Formulations For Management Of Powdery Mildew And Mites, Adriane Lorraine Cannon Dec 2004

Evaluation Of Botanical Oil Formulations For Management Of Powdery Mildew And Mites, Adriane Lorraine Cannon

Masters Theses

Experiments were conducted to evaluate the effects of newly created soybean oil formulations on powdery mildew (Erysiphe pulphra ), photosynthesis, phytotoxicity, and broad mites (Polyphagotarsonemus latus (Banks)) on dogwood ( Cornus florida (L.) 'Cloud Nine') trees, and to evaluate the amounts of formulations that are deposited and washed off of peach (Prunus persica, (L.)) leaves, dormant oak (Quercus phellos, (L.) ), and viburnum ( Viburnum x juddii) twigs after simulated rainfall. Oil treatments were applied using a back pack mist blower sprayed pre- and post- inoculation of powdery mildew to evaluate powdery mildew, …


Occurrence Of Escherichia Coli0157:H7 In Diverse Farm Environments In Five States, Carl Andrew Doane Dec 2004

Occurrence Of Escherichia Coli0157:H7 In Diverse Farm Environments In Five States, Carl Andrew Doane

Masters Theses

In the United States, foodborne outbreaks of Escherichia coli O157:H7 illness have often been linked to the consumption of contaminated, undercooked ground beef. However, the occurrence of E. coli O157:H7 in other animals has also been reported. The objective of this study was to determine the occurrence of E. coli O157:H7 in cattle, swine, poultry, and farm environments. Environmental samples (n=576) and fecal swab samples (n=1686) from sixteen locations in the U.S. were collected over 22 months. Overall, in fecal swabs E. coli O157:H7 was positive (serologically confirmed) in 4.7% of beef cattle (n = 408), 3.9% of dairy cattle …


Assessing Capacity For Collaborative Land Management In A Western Tennessee Community, Leslie Ann Horner Dec 2004

Assessing Capacity For Collaborative Land Management In A Western Tennessee Community, Leslie Ann Horner

Masters Theses

Human and natural alterations resulting in sedimentation, flooding, and hardwood tree mortality in western Tennessee’s Hatchie River watershed represent a landscape-level natural resource problem. Flooding and tree mortality have significant negative economic impacts on the residents of the watershed’s communities. Efforts to address these ecological problems will need to be conducted at a landscape level, across various boundaries, involving multiple private landowners. In order to succeed in a cross-boundary restoration approach, the needs of the people and the ecosystem must be addressed. Collaboration in natural resource management has emerged as one tool for discovering and maintaining a balance between community …


Relationships Between Muskrats And Freshwater Mussels Prior To River Otter Restoration At Mammoth Cave National Park, Kentucky, Kimberly Ann Asmus Dec 2004

Relationships Between Muskrats And Freshwater Mussels Prior To River Otter Restoration At Mammoth Cave National Park, Kentucky, Kimberly Ann Asmus

Masters Theses

The southeastern United States has a great diversity of freshwater mussel species, many of which are threatened with extinction. The muskrat (Ondatra zibethicus) is one of the few animals to extensively prey on freshwater mussels, and it has been implicated in retarding the recovery of, or further threatening, some endangered mussel populations. Muskrat predation on mussels may be significant at Mammoth Cave National Park (MCNP) where a river otter (Lontra canadensis) restoration has been proposed. Anecdotal observations suggest that the reintroduction of river otters dramatically reduces muskrat populations, which, in tum, may reduce the number of …


Development And Characterization Of Monoclonal Antibodies Directed Against Tanapox Virus, Michael Franz Dec 2004

Development And Characterization Of Monoclonal Antibodies Directed Against Tanapox Virus, Michael Franz

Masters Theses

The initial symptoms of a Tanapoxvirus (TPV) infection are indistinguishable from smallpox, which is caused by variola virus (VV). In the post-9/11 area, reagents that can quickly differentiate a TPV infection from smallpox are very desirable, but currently unavailable. Monoclonal antibodies (mAbs) directed specifically against TPV can be used for this purpose. Six mAbs were developed and characterized that specifically bind to TPV infected owl monkey kidney (OMK) cells, but not uninfected cells. The apparent molecular mass of the TPV protein(s) recognized by 5 mAbs were calculated using the Western blot technique. One mAb demonstrated no binding using the Western …


Seasonal Abundance Of Mosquitoes (Diptera: Culicidae) At A High And Low Prevalence Site For La Crosse Encephalitis In Eastern Tennessee, Nathan David Caldwell Dec 2004

Seasonal Abundance Of Mosquitoes (Diptera: Culicidae) At A High And Low Prevalence Site For La Crosse Encephalitis In Eastern Tennessee, Nathan David Caldwell

Masters Theses

La Crosse (LAC), a California (CAL) serogroup bunyavirus, is the most prevalent pediatric arboviral disease in the United States and accounts for virtually all encephalitis cases associated with CAL serogroup arboviruses. In Tennessee, USA, prior to the drastic increase of confirmed La Crosse (LAC) encephalitis cases in 1997, the sum of documented cases reported to the Tennessee Department of Health totaled 9. During subsequent years in Tennessee (1997 to 2003), an average of 12 cases has been reported annually. Approximately 62% of these reported cases have occurred in the months of July and August. The native, container-inhabiting mosquito Ochlerotatus triseriatus …


Insulin Sensitivity And The Onset Of Hyperphagia In Fatty Rats, Holiday Agnes Durham Dec 2004

Insulin Sensitivity And The Onset Of Hyperphagia In Fatty Rats, Holiday Agnes Durham

Masters Theses

Hyperphagia emerges suddenly after 22 days of age in Zucker fatty (fa/fa) rats, and fatties become visibly obese within days. This rapid increase in growth rate is likely to be associated with substantial changes in glucose metabolism. The objective of these experiments was to determine the relationship between insulin resistance and the onset of hyperphagia. Insulin tolerance tests showed that fatties were remarkably insulin resistant prior to the onset of hyperphagia, hyperinsulinemia, and obesity, but become as insulin sensitive as their lean littermates after the onset of hyperphagia. Furthermore, fatties became increasingly insulin resistant prior to the onset of …


Prostaglandin E2 Secretion And Effect On Adipocyte Lipogenesis, Patrick Allen Wortman Dec 2004

Prostaglandin E2 Secretion And Effect On Adipocyte Lipogenesis, Patrick Allen Wortman

Masters Theses

With the current focus on the role of n-3 PUFAs as beneficial dietary interventions in the fields of cardiovascular disease and cancer, there has been a vastly increased awareness and focus on the mechanism of action for these essential fatty acids.

Many of the effects of PUFAs are mediated via changes in prostaglandin (PG) levels. One primary substrate for PGs is arachidonic acid (AA) (20:4 n-6), which results in the production of 2-series PGs. Increased concentrations of AA have been shown to increase levels of PGE2 in vitro and in vivo. The omega-3 fatty acid EPA (20:5 n-3) is …


Antimicrobial Activity Of Trypsin And Pepsin Hydrolysates Derived From Acid-Precipitated Bovine Casein, Kellie Parks Burris Dec 2004

Antimicrobial Activity Of Trypsin And Pepsin Hydrolysates Derived From Acid-Precipitated Bovine Casein, Kellie Parks Burris

Masters Theses

Foodborne pathogens are a major concern to the food industry and consumers but they may be controlled with antimicrobials. Naturally occurring antimicrobials may be isolated from a variety of plant, animal and microbial sources. Previous studies have demonstrated that peptides isolated from enzyme hydrolyzed milk proteins may have in vivo and in vitro antimicrobial activity. Such compounds could be of use as inhibitors of foodborne pathogens. The objectives of this study were to determine the antimicrobial effectiveness against Salmonella Typhimurium and Listeria monocytogenes of digests of bovine acid-precipitated casein with the enzymes pepsin and trypsin and to determine if these …


Prescribed Burning In Tennessee: Importance And Barriers, Goals, And Information Needs Of Private, State, And Federal Managers, Brian T. Hemel Aug 2004

Prescribed Burning In Tennessee: Importance And Barriers, Goals, And Information Needs Of Private, State, And Federal Managers, Brian T. Hemel

Masters Theses

Early in the 20th century, intense and severe wildfires were frequent due to abundant fuels generated by logging and the presence of anthropogenic ignition sources in close proximity to these fuels. As timber was depleted, this period of lumbering ceased and the realization that vast tracts of cutover land had to be reforested and protected led to the inception of fire suppression organizations and techniques. The fire exclusion that occurred over much of the 20th century due to organized fire suppression efforts has led to two sets of problems: the buildup of fuels and the decline of fire-adapted …


Prevalence Of Potential Zoonotic Enteric Bacterial Pathogens In Dogs And Cats And Factors Associated With Potential Transmission Between Animals And Humans, Omaima Maamoun Ahmed Aug 2004

Prevalence Of Potential Zoonotic Enteric Bacterial Pathogens In Dogs And Cats And Factors Associated With Potential Transmission Between Animals And Humans, Omaima Maamoun Ahmed

Masters Theses

With the discovery of the human immunodeficiency virus (HIV) and acquired immune deficiency syndrome (AIDS), concerns about dangers of pet ownership have increased. Zoonotic organisms associated with cats and dogs, may cause life-threatening infections in immuosuppressed human beings. The objectives of this project were to determine the prevalence of potential zoonotic enteric pathogens (Salmonella, Listeria, and Campylobacter) in feces of dogs and cats (diarrheic, healthy, and hospitalized), to evaluate the association of diarrhea in dogs and cats with diarrhea in human beings sharing the same household, and to evaluate the antimicrobial susceptibility of Salmonella, Listeria …


Identifying The Signature Of The Natural Attenuation Of Mtbe In Groundwater Using Molecular Methods And "Bug Traps", Anita Eva Biernacki Aug 2004

Identifying The Signature Of The Natural Attenuation Of Mtbe In Groundwater Using Molecular Methods And "Bug Traps", Anita Eva Biernacki

Masters Theses

Natural attenuation through intrinsic bioremediation is the risk-based management approach commonly used for gasoline (BTEX) contamination sites. This approach has not yet been utilized for the fuel oxygenate methyl tertiary-butyl ether (MTBE). MTBE is more resistant to biodegradation than BTEX. MTBE is more abundant than benzene in oxygenated gasoline, has a greater water solubility than BTEX, and sorbs weakly to soil. These properties complicate developing a risk based management option to be implemented as easily as for BTEX. The purpose of this project is to contribute to a growing database containing information on MTBE contaminated sites nationwide with a variety …


Examining Varroa-Resistant Honey Bee Queens From Commercial Breeders: Colony Productivity, Hygienic Behavior, Suppression Of Mite Reproduction, And The Relationship Of Juvenile Hormone Iii To Mite Abundance, Laura L. Bryant Aug 2004

Examining Varroa-Resistant Honey Bee Queens From Commercial Breeders: Colony Productivity, Hygienic Behavior, Suppression Of Mite Reproduction, And The Relationship Of Juvenile Hormone Iii To Mite Abundance, Laura L. Bryant

Masters Theses

This research was conducted to assess the performance of commercially bred honey bee queens sold as resistant to the parasitic mite, Varroa destructor. The study’s objectives were to: 1) Compare honey and pollen stores and V. destructor infestation in colonies established with hybrid Russian, SMR, and control queens, 2) Determine levels of hygienic behavior and mite non-reproduction in the same colonies, and 3) Determine the relationship between juvenile hormone III in honey bee larvae and V. destructor reproduction.

In Part One, when honey, pollen, and V. destructor levels were measured, no significant differences were found among types of queens. …


Reproductive Efficiency Following Administration Of An Inhibitor Of Prostaglandin F During Early Embryonic Development In Dairy Cattle, Charles Dexter Young Aug 2004

Reproductive Efficiency Following Administration Of An Inhibitor Of Prostaglandin F2Α During Early Embryonic Development In Dairy Cattle, Charles Dexter Young

Masters Theses

A study was performed to examine the administration of flunixin meglumine (FM; an inhibitor of prostaglandin F) following artificial insemination on pregnancy rates of lactating dairy cattle. Jersey and Holstein cows (n=106) were randomly assigned to receive intravenously either FM (2.2 mg/kg BW) or saline (SAL; 1 mL/23 kg BW). Cows were randomly allotted to treatment by lactation number, bovine somatotropin administration, breed, BW, days in milk, milk production, and 305 ME milk production. Study was performed from September through April and all cows were milked twice daily. Following estrous synchronization (cloprostenol, 500 µg im), cows were artificially …


Atmospheric Plasma Inactivation Of Foodborne Pathogens On Fresh Produce Surfaces, Faith Michelle Johnson Aug 2004

Atmospheric Plasma Inactivation Of Foodborne Pathogens On Fresh Produce Surfaces, Faith Michelle Johnson

Masters Theses

A study was conducted to determine the effect of a one atmosphere uniform glow discharge plasma (OAUGDP) on inactivation of nalidixic acid resistant Escherichia coli O157:H7 and Salmonella, and Listeria monocytogenes on apples, cantaloupe, and lettuce, respectively, and culture media [tryptic soy agar (TSA) + 50 ppm nalidixic acid (TSAN) for E. coli O157:H7 and Salmonella; TSA for L. monocytogenes). A mixture of cultured test organisms was washed, suspended in phosphate buffer and spot inoculated onto produce or culture media (6 log CFU/sample). Inoculated produce or culture media (samples) were exposed inside a chamber affixed to the …


Production And Characterization Of Fungal Chitin And Chitosan, Tao Wu Aug 2004

Production And Characterization Of Fungal Chitin And Chitosan, Tao Wu

Masters Theses

Chitin is a biopolymer. Theoretically, it is a homopolymer of acetyl-glucosamine. Chitosan is the deacetylated product of chitin. Chitin and chitosan have many applications in water purification, agriculture, food and pharmaceutical industries. Currently, industrial production for chitin and chitosan is from the shell wastes. The objective of this study was to evaluate the feasibility of chitin and chitosan production from fungal sources.

The accumulation of chitin and chitosan during A. bisporus storage and Aspergillus niger and Mucor. rouxii. Growth was evaluated by total glucosamine determination. Chitin and chitosan were extracted from biomass by alkali and acid treatment and yield and …


Associations Between Eastern Hemlock (Tsuga Canadensis) And Avian Occurrence And Nest Success In The Southern Appalachians, David Aaron Keller Aug 2004

Associations Between Eastern Hemlock (Tsuga Canadensis) And Avian Occurrence And Nest Success In The Southern Appalachians, David Aaron Keller

Masters Theses

The recent decline of eastern hemlock (Tsuga canadensis) is a dramatic example of the effects exotic insect pests can have on forest composition and structure. Hemlock decline is attributed to defoliation caused by hemlock woolly adelgid (HWA, Adelges tsugae), an exotic Hemipteran introduced to the northwest U.S. from Asia during the 1920s and the eastern U.S. during the early 1950s. Within the past several years, HWA infestations have reached the southern portions of the Appalachian mountains and threaten to eliminate both eastern and Carolina hemlock (Tsuga carolinensis) from the region.

Recognized as nationally important bird …


A Survey Of Visitors To Mt. Leconte In The Great Smoky Mountains National Park, Amy Lynn Mathis Aug 2004

A Survey Of Visitors To Mt. Leconte In The Great Smoky Mountains National Park, Amy Lynn Mathis

Masters Theses

This study focuses on the behaviors, attitudes, perceptions and preferences of visitors to Mt. LeConte in the Great Smoky Mountains National Park. Mt. LeConte (elevation 6,593 ft.) is a popular tourist destination year-round. In addition to the trails that access the summit, there is a backcountry shelter and a rustic lodge, built in 1926, for overnight guests. The upcoming expiration of the Concession Contract for Mt. LeConte Lodge makes it necessary to conduct an Environmental Assessment. This project serves the dual objectives of providing data needed for the Environmental Assessment (EA) and meeting the General Management Plan requirement to monitor …


The Relationship Between Steps Per Day And Bone Variables In Healthy Postmenopausal Women, Olivera Lukajic Aug 2004

The Relationship Between Steps Per Day And Bone Variables In Healthy Postmenopausal Women, Olivera Lukajic

Masters Theses

The primary purpose of this study was to examine the relationship between ambulatory physical activity (steps per day) and bone variables in healthy, Caucasian postmenopausal women. Additionally, we examined the relationship of body mass (BM), lean mass (LM), and fat mass (FM) with bone variables in this group of women, Average steps taken per day were compared to bone mineral density (BMD) in 93 postmenopausal women (60.8 ±5.8 yrs). Ambulatory physical activity (steps per day) was measured for 14 consecutive days using a Yamax Digi-Walker SW-200. Additionally, current physical activity (PA) level was estimated using a Paffenbarger Physical Activity Index …


Alumni Perceptions: A Review Of The Curriculum Within The Recreation Program At The University Of Tennessee, Knoxville, Angela Jeneanne Wozencroft Aug 2004

Alumni Perceptions: A Review Of The Curriculum Within The Recreation Program At The University Of Tennessee, Knoxville, Angela Jeneanne Wozencroft

Masters Theses

The purpose of this study was to examine the perceptions of alumni who had graduated from The University of Tennessee, Knoxville’s (UTK) recreation program. The data collection tool used in this study was a questionnaire developed by the researcher. The questionnaire gathered information from the alumni on the following research questions:

1. How many graduates were employed in the field of recreation upon graduation and what were some of the reasons for one not being employed in the field?

2. What were the alumni’s perceptions of the quality of their education, from the recreation program, in relation to their demands …


Establishment Of Upland And Bottomland Hardwood Agroforestry Plantations In Tennessee And Mississippi, David Michael Casey Aug 2004

Establishment Of Upland And Bottomland Hardwood Agroforestry Plantations In Tennessee And Mississippi, David Michael Casey

Masters Theses

The feasibility of alley cropping as a means of afforestation was studied across seven different study sites in western Tennessee and northern Mississippi. Seeds were collected from 11 oak (Quercus spp) species and black walnut (Jug/ans nigra L.) trees in the region and grown under nursery protocols that are designed to produce seedlings of optimal size in one year. Seedlings were lifted by genetic family after one year and initial seedling measurements were recorded. Four bottomland studies and three upland studies were then sorted into an incomplete block design with multiple species and families within each block. …


Teachers' Perceptions And Concerns Of Year-Round Education In Tennessee High School Agriculture Programs, Gary Lee Blackwell Jr. Aug 2004

Teachers' Perceptions And Concerns Of Year-Round Education In Tennessee High School Agriculture Programs, Gary Lee Blackwell Jr.

Masters Theses

The purpose of this study was to focus on the emergence of year-round education and its possible effects on agricultural education programs throughout the state of Tennessee. The study collected perceptions of teachers who currently teach in a Tennessee high school agriculture program regarding the implementation of a year-round program at their school.

A survey was designed and sent to all 284 teachers identified in the 2002-2003 Tennessee Agriculture teacher directory. Findings were based upon a 69% response rate.

Findings

  • The total number of survey respondents was 197; of these 93 .1 % taught in schools operating on a traditional …


Performance And Fertility Of Yearling Beef Bulls Grazing Endophyte-Infected Tall Fescue Pastures, Gustavo Martin Schuenemann Aug 2004

Performance And Fertility Of Yearling Beef Bulls Grazing Endophyte-Infected Tall Fescue Pastures, Gustavo Martin Schuenemann

Masters Theses

During a two-year study, 80 bulls and 80 steers were utilized to determine the effects of grazing endophyte-infected tall fescue on growth performance, semen parameters, endocrine profiles, and IVF. Bulls and steers were allotted to graze Kentucky 31 tall fescue (Festuca arundinacea Schreb.) infected with Neotyphodium coenophialum, an ergot alkaloid-producing fungal endophyte new stand (E+New; n = 20/yr), old stand (E+Old; n = 20/yr), E+Old plus ladino (Trifolium repens) and red (T. pratense) clovers (E+Cl; n = 20/yr), or Jesup tall fescue with the non-ergot alkaloid-producing endophyte MaxQTM (MaxQ; n = 20/yr). Bulls and steers were grouped by body …


Inactivation Of Escherichia Coli O157:H7 And Listeria Monocytogenes By High-Intensity Ultrasound In The Presence Of Salts, Kimberly D. Stanley Aug 2004

Inactivation Of Escherichia Coli O157:H7 And Listeria Monocytogenes By High-Intensity Ultrasound In The Presence Of Salts, Kimberly D. Stanley

Masters Theses

Inactivation of Escherichia coli O157:H7 and Listeria monocytogenes suspended in salt solutions Na2PO4, NaCl, NaNO3, NH4Cl, CaCl2, AlCl3, and L. monocytogenes in salt solutions NaCl, NaNO3, AlCl3 at concentrations ranging from 0 to 5% (wt/vol) by high-intensity ultrasound at two different temperature conditions (ice water bath, 40ºC water bath) and three ultrasonic intensity levels (9.49, 21.83, 49.22 W/cm2) was determined. Increases in sonication treatment time, intensity and temperature led to increased lethality of both pathogens. However, cell lethality, as a function of solute concentration, varied depending upon type of salt. CaCl2, NaCl, NaNO3, NaPO4, and NH4Cl had little or no …


Benefits And Challenges Of Service-Learning In Tennessee 4-H Youth Development: A Delphi Study, Lori Jean Mantooth Aug 2004

Benefits And Challenges Of Service-Learning In Tennessee 4-H Youth Development: A Delphi Study, Lori Jean Mantooth

Masters Theses

The purpose of this study was to identify benefits and challenges of implementing service-learning in Tennessee 4-H Youth Development. Furthermore, the researcher sought to describe any perceived differences among three subgroups: 4-H members, volunteers, and Extension agents.

A purposefully selected panel of 10 4-H youth, 10 volunteers, and 10 4-H agents utilized the modified Delphi Technique to generate and prioritize benefits and challenges of conducting service-learning projects in Tennessee 4-H Youth Development. Data were gathered through three rounds of questionnaires administered to the panel through the mail and/or the Internet. The first round of questionnaires asked panel members to generate …