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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Microbiotic Assessment of an Upflow Anaerobic/Aerobic Swine Treatment Process

McClain, Robert Earl 12 May 2001 (has links)
Confined animal feeding operations (CAFOs) relating to swine and their resulting odors continues to be an issue of concern. The primary sources of odors from a CAFO include general ventilation of the confinement house, the anaerobic lagoon, and the land application of lagoon sludge. This paper focuses on lagoon wastewaters, but the results therein could have influence on the other two aforementioned areas. An advanced upflow anaerobic/aerobic reactor system was developed to determine its impact on microbial activities that ultimately result in offensive odors. The microbial activity of SRB (sulfate-reducing bacteria) and hydrogen-sulfide production was monitored closely in each ?zone?, as well as other parameters such as dissolved oxygen and BOD. The results indicated a microbial physiology conducive to offensive odor production in the anaerobic zone of the pilot reactor and an aerobic microbial population in the upper zone of the pilot reactor. This aerobic zone was found to be effective in oxidizing the odorous gases created in the anaerobic zone. The overall microflora was consistent with an average magnitude of 108 CFU/mL. From the analysis performed, it was concluded that the microbiotic flora development and related substrate decomposition was the result of different metabolic pathways employed by the microflora rather than changes in the microbial population. In addition, the rise in pH throughout the experiment indicated the impact of the protein metabolic pathways (ammonification) over the carbohydrate metabolic pathways. Overall, the upflow anaerobic/aerobic pilot reactor proved to be an effective method for ?zoning? of the microbiotic flora, and a positive impact on the modifying the compounds related to offensive odor production.
12

Functional analysis of some yeast genes

El-Hassi, Mohamed F. January 1997 (has links)
A series of mutant strains of the yeast Saccharomyces cerevisiae that are sensitive to osmotic stress and also have a defect in vacuolar biogenesis have been isolated (M. Latterich, PhD Thesis 1992). The mutations that cause this pleiotropic phenotype are termed ssv, for salt sensitive vacuolar mutants. Complementation analysis has revealed that ssv mutations fall into one of 18 complementation groups. A MAP kinase related signal transduction pathway, termed the HOG pathway for High Osmolarity Glycerol, has been identified in yeast. This pathway senses osmotic stress and invokes the cellular response, one aspect of which is the accumulation of intracellular glycerol (Brewster et. al, 1993). Mutations in the HOG pathway often cause an osmosensitive phenotype similar to that shown by ssv mutations. This work sets out to characterise several ssv strains for defects in the HOG pathway. These strains were subjected to osmotic stress and the intracellular and extracellular glycerol determined and compared to control strains and conditions. Many of the strains showed reduced, or even elevated in one case, glycerol levels compared to wild-type strains. No correlation could be made between these glycerol levels and the activity of the rate-limiting enzyme, glycerol-3-phosphate dehydrogenase (GPDH) determined in an independent study. Transcription of the GPDH gene is under the control of the HOG pathway. In a separate study, the nucleotide sequence of a short region of yeast chromosome VII was determined. Approximately 11,000 bases of DNA from the right sub-telomeric region was sequenced. Analysis of the DNA sequence showed four potential open reading frames. One of these encoded the YORl gene and another a protein related to PAU1 The remaining two ORFs, termed ORFl and ORF2, encoded potential proteins of unknown function. Disruption cassettes containing the LEU2 selectable marker were constructed for both ORFl and ORF2. Successful disruption of ORFl was achieved, but no viable transformants were ever recovered after attempted disruption of 0RF2..ORFl gene knockouts are viable and show no observable phenotype under a range of growth conditions. Subsequent analysis of ORFl and 0RF2 after the completion of the Yeast Genome Project, shows that both ORFl and 0RF2 are members of different sub- telomeric associated gene families. 0RF2 encodes a putative Y' protein.
13

CHARACTERIZING POPULATION GENETIC STRUCTURE AND INFERRING THE INFLUENCE OF LANDSCAPE FEATURES ON GENE FLOW IN A TEMPERATE SNAKE SPECIES

Xuereb, Amanda 30 October 2012 (has links)
Patterns of genetic diversity in natural systems are influenced by landscape heterogeneity over spatial and temporal scales. Certain natural or anthropogenic landscape features may facilitate or impede organism dispersal and subsequent gene flow. Characterizing the geographical distribution of genetic diversity and identifying the factors contributing to population genetic structure is imperative for maintaining functional connectivity between isolated populations across a fragmented landscape. In this study, I combined genetic data and high-resolution land cover information to investigate patterns of population genetic structure in the threatened eastern hog-nosed snake (Heterodon platirhinos) at its northern range limit in Ontario, Canada. First, using putatively neutral microsatellite markers, I found evidence of genetic differentiation between two geographically disjunct regional populations: in the Carolinian region of southwestern Ontario, and along the eastern shoreline of Georgian Bay. Spatial and non-spatial Bayesian clustering algorithms also detected population genetic structure within each regional population. I found evidence of weak structure within Georgian Bay, roughly corresponding to regions north and south of Parry Sound. A genetic cluster at Wasaga Beach, located at the southern terminus of Georgian Bay, was highly differentiated from other populations, despite its geographic proximity to Georgian Bay. Excess homozygosity and reduced allelic diversity in Wasaga Beach compared to other sampled populations imply a population bottleneck event. Secondly, I inferred the role of landscape features on eastern hog-nosed snake dispersal and subsequent gene flow in the Georgian Bay regional population. Using techniques derived from electrical circuit theory, I estimated pairwise resistance distances between individuals by assigning costs to landscape features that are predicted to impede hog-nosed snake movement: open water, wetland, settlement and agriculture, and roads. Landscape features did not influence genetic structure within Wasaga Beach. However, I found weak evidence for an effect of landscape features, particularly open water and roads, on gene flow in eastern Georgian Bay. This study is the first to examine potential factors driving population genetic structure of eastern hog-nosed snakes and provides an empirical foundation for future tests of demographic models and spatially explicit simulations of gene flow. / Thesis (Master, Biology) -- Queen's University, 2012-10-30 11:58:05.094
14

Studies on Hog Plasma Lecithin:cholesterol Acyltransferase: Isolation and Characterization of the Enzyme

Park, Yong Bok 05 1900 (has links)
Lecithin:cholesterol acyltransferase (LCAT) was isolated from hog plasma and basic physicochemical properties and functionally important regions were investigated. Approximately one milligram of the enzyme was purified to apparent homogeneity with approximately a 20,000-fold increase in specific activity. In the plasma, hog LCAT was found to associate with high-density lipoproteins (HDL) probably through hydrophobic interactions with apolipoprotein A-I. HDL was the preferred lipoprotein substrate of the enzyme as its macromolecular substrate. The enzyme was found to contain 4 free sulfhydryl groups; at least one of these appeared to be essential for catalytic activity. The enzyme had a tendency to aggregate at high concentrations. More than half of the tryptophan and none of the tyrosine residues of the enzyme were shown to be exposed to the aqueous environment based on fluorescence and absorbance studies, respectively.
15

Assessing the impact of feral hog populations on the natural resources of Big Thicket National Preserve

Chavarria, Pedro Mazier 15 May 2009 (has links)
The Big Thicket National Preserve (BTNP) is a unit of the National Park Service whose mission prioritizes conservation of its wildlands in the United States. One threat to natural resources of the BTNP has been impacts associated with feral hog (Sus scrofa) activities. Population numbers of this non-native game species have increased throughout Texas, including areas within the preserve. Recreational hunting permitted by the BTNP has served as a means of controlling hog numbers, although the reported amounts of hog damage to park resources appear to have increased in recent years. Population reduction of feral hogs and mitigation of their impacts require research that documents and validates feral hog impacts on park resources. Here, I evaluated (1) population trends of feral hogs for the past 20 years via data from hunter-card surveys and track-counts, and (2) feral hog impacts on native vegetation for 3 management units of the BTNP. Results from my analysis suggest a nearly 3-fold increase in hog numbers throughout the preserve since 1981. The overall damage to vegetation from hog rooting or wallowing averaged to 28% among the 3 units of the BTNP. Landscape features such as topography, soil moisture, soil type, and dominant vegetative cover types were used to predict hog damage. Floodplains had the most damage in the Big Sandy unit (45%), while flatlands were mostly impacted in the Turkey Creek unit (46%), and uplands in the Lance Rosier unit (32%). Vegetative cover was an important variable in explaining variation in hog damage throughout the 3 units of the preserve. Impacts were more widespread across different vegetative strata than previously believed. Study results also support the premise that hog damage in the BTNP parallels the increase in hog abundance over the past 20 years. A more aggressive program for population reduction of feral hogs and mitigation of their impacts is recommended for the BTNP to continue to meet its legal mandates for conservation.
16

Abatement Strategies and Disease Assessment for Feral Hogs in East Texas

Sumrall, Samuel Aaron 2011 May 1900 (has links)
Feral hogs (Sus scrofa) are considered an exotic, free-ranging ungulate distributed within numerous countries and continents to include the United States. The reproductive efficiency, lack of predators, land use practices for domestic livestock (e.g., feeding stations, introduced water sources, intense cropping practices, etc.), and diet are leading factors in the expansion of feral hogs throughout their range. Feral hogs negatively impact floral and faunal communities, agricultural lands, and residential and recreational areas to include concerns with public safety and disease transmission. My study objectives were to (1) assess feral hog abatement strategies by (A) evaluating trap designs with the inclusion of electrical fencing, and (B) evaluating candidate baits for feral hog-specificity, and (2) assess prevalence levels for feral hog diseases. I evaluated 3 corral trap designs differing in the addition of electric fence configurations. Feral hog capture success data were collected and used to determine trap design efficacy. Treatments evaluated included (A) control corral trap with no electrical configurations, (B) corral trap with 1 electrical leg, and (C) corral trap with 2 electrical legs. ANOVA analyses suggest no differences (df = 2, P = 0.758) between trap designs; however, length of trapping effort (i.e., the number of days that trapping occurred) was a significant (df = 6, P < 0.001) factor in determining trap success. Pre-baiting was an important factor in observed trapping success. Trapping success declined after fourth day of continuous trapping. I recommend short, intensive trapping efforts (e.g., <4 days) when using corral traps in feral hog abatement programs. I also evaluated 14 candidate baits (with and without repellant) replicated 40 times to determine feral hog specificity. Three evaluated baits (i.e., PIGOUT™ strawberry, corn, and rice) were selected (df = 2, P < 0.05) more frequently by feral hogs than other combinations. Non-target species (e.g., raccoons) visited baits with repellants less (df = 2, P < 0.05) than baits without repellants. Repellant had no direct impact on feral hog visitation at bait sites. Trapping data also suggests that grains commonly farmed in local or regional areas are more likely to be consumed by feral hogs and, therefore considered in baiting options. Finally, of 412 feral hogs captured, 86 were sampled for prevalence of pseudorabies and Brucella suis. The prevalence of pseudorabies and B. suis was 20.9% and 13.9%, respectively within the study area. Based on disease study results, I recommend that natural resource managers take necessary precautions to protect themselves by wearing protective equipment and equipment and properly cooking feral hog meat. Additionally, resource managers should properly administer vaccinations to domestic and companion animals, and restricting domestic and companion animals from areas of high risk (e.g., carcasses of dead hogs and wallows).
17

EFFECT OF SOLID CATTLE MANURE AND LIQUID HOG MANURE APPLICATION ON PHOSPHORUS AND NITROGEN IN SOIL, RUN-OFF AND LEACHATE IN SASKATCHEWAN SOIL

2015 September 1900 (has links)
Traditional application methods in which manure is simply broadcast on the soil surface are being replaced by innovative methods that place the manure in the soil in bands, potentially increasing efficiency of manure nutrient utilization by crops and reducing losses to the environment. Limited information exists on the pools and mobility of phosphorus (P) and nitrogen (N) in soils receiving repeated applications of animal manure using different application methods. The overall objective of the thesis research is to determine the fate of manure nutrients applied using new subsurface banding technology, as it affects crop response and uptake, residual nutrients in the soil, and transport (lateral and vertical) by water off-site. Specific objectives were: 1) to determine yield response to solid cattle manure (SCM) and the recovery of SCM and liquid hog manure (LHM) P and N using broadcast manure placement and new subsurface banding technology, 2) to determine the amount of soluble reactive phosphorus (SRP) and N that is transported in snowmelt water moving across soils receiving different rates and methods of application of manure, and 3) to determine the amount and proportion of SRP and N that are transported downward in a SCM amended soil profile with leaching water as influenced by manure rate and placement. In-soil placement of SCM in bands had a small impact on improving crop yield and nutrient uptake in a 3 year crop rotation in east-central Saskatchewan compared to broadcast, and broadcast and incorporate application strategies. In-soil placement of manure was also not effective in reducing P and N export in snowmelt water. Export of P and N downward in leachate water in intact cores was increased by in-soil manure placement, especially when placed in bands. This is attributed to reduced fixation of manure N and P and enhanced solubilization when manure is placed in soil in bands versus a broadcast application. Overall, nutrient export was significantly lower in frozen versus thawing soils, and export of P in soils receiving liquid hog manure was much less than in soils receiving solid cattle manure which is attributed to the higher P content in cattle manure.
18

Ανίχνευση ανθρώπου και παρακολούθηση της κίνησής του

Βλαχοστάθης, Σωτήριος 13 January 2015 (has links)
Η διάδοση της χρήσης των υπολογιστών σε όλο και περισσότερους τομείς της καθημερινής μας ζωής, καθώς και η τεχνολογική εξέλιξη στην επιστήμη των υπολογιστών είχε σαν φυσικό επακόλουθο τη δημιουργία αλγορίθμων που έχουν στόχο την ανίχνευση και την αναγνώριση ανθρώπων με ακρίβεια καθώς και την παρακολούθηση τους. Τέτοιοι αλγόριθμοι εφαρμόζονται κυρίως σε συστήματα οπτικής επιτήρησης που είναι ζωτικής σημασίας σε διάφορους τομείς της καθημερινότητας. Αντικείμενο της παρούσας διπλωματικής εργασίας είναι η υλοποίηση ενός συστήματος ανίχνευσης, με τη χρήση του αλγόριθμου Histogram of Oriented Gradient (HOG), ταξινόμησης με χρήση Supported Vector Machines και παρακολούθησης ανθρώπου σε ακολουθία εικόνων, με χρήση αλγορίθμων υπολογιστικής όρασης όπως είναι ο αλγόριθμος φιλτραρίσματος σωματιδίων (Particle Filtering). / The widespread use of computers in more and more areas of our everyday life and the technological development in computer science as a natural consequence was the creation of algorithms that aim to detect and identify people accurately and monitor them. Such algorithms, are applied mainly in visual surveillance systems and is of vital importance in various areas of everyday life. The subject of this thesis is to implement a detection system using the algorithm Histogram of Oriented Gradient (HOG) as well, sort using Supported Vector Machines and the human tracking in image sequence, using computer vision algorithms such as Particle Filtering algorithm.
19

Pedestrian Detection on FPGA

Qureshi, Kamran January 2014 (has links)
Image processing emerges from the curiosity of human vision. To translate, what we see in everyday life and how we differentiate between objects, to robotic vision is a challenging and modern research topic. This thesis focuses on detecting a pedestrian within a standard format of an image. The efficiency of the algorithm is observed after its implementation in FPGA. The algorithm for pedestrian detection was developed using MATLAB as a base. To detect a pedestrian, a histogram of oriented gradient (HOG) of an image was computed. Study indicates that HOG is unique for different objects within an image. The HOG of a series of images was computed to train a binary classifier. A new image was then fed to the classifier in order to test its efficiency. Within the time frame of the thesis, the algorithm was partially translated to a hardware description using VHDL as a base descriptor. The proficiency of the hardware implementation was noted and the result exported to MATLAB for further processing. A hybrid model was created, in which the pre-processing steps were computed in FPGA and a classification performed in MATLAB. The outcome of the thesis shows that HOG is a very efficient and effective way to classify and differentiate different objects within an image. Given its efficiency, this algorithm may even be extended to video.
20

PIGS IN SPACE: GHOSTS, GENDER AND SEXUALITY IN A DEBATE ABOUT REGULATING INDUSTRIAL HOG FARMS IN KENTUCKY

Curran, Mary E. 01 January 2002 (has links)
In 1997, Governor Paul Patton of Kentucky asked the state Cabinet of Natural Resources and Environmental Protection to develop administrative regulations for industrial hog farms in the state. The regulatory process has been contentious. From 1997 through 1998, the Cabinet held five public hearings to elicit comments on the proposed regulations. This study is designed to answer two questions. First, how, within parameters of participation established by the Kentucky Cabinet of Natural Resources and Environmental Protection, have participants in the debate deployed notions of risk to privilege certain gendered and sexualized farming identities, farming practices, and notions of rurality? Second, how will the spatial arrangements proposed by participants alter social relationships? A theoretical framework that draws from Foucaults work on governmentality and power/knowledge, feminist theories and Latours actor network theory was developed for this analysis which combines discourse analysis with participant observation. The study examines texts produced by the Cabinet and three groups: the Kentucky Farm Bureau Federation, Kentuckians for the Commonwealth and Community Farm Alliance. Texts include transcripts of hearing comments, published histories, newspapers and web sites produced by three studied, law suits related to the debate, and newspaper coverage of the debate. Participant observation was conducted at public hearings and meetings of the Kentuckians for the Commonwealth and Community Farm Alliance. Results from this project suggest that gender and sexualization play very important roles in establishing hierarchies between organized groups and government agencies. Results also indicate that the constructions of farmers, farming and rurality produced by hierarchical relationships are largely dependent on distinct spatial arrangements which have very real effects on human-human, human-environment and human-animal relationships.

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