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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.
81

Užití trombelastografie při hodnocení koagulace u žen s fyziologicky a patologicky probíhajícím těhotenstvím / The Use of Thromboelastography in Evaluation of Coagulation in Fenmales with Physiologial or Pathological Pregnancy

Polák, Ferdinand January 2011 (has links)
The Use of Thromboelastography in Evaluation of Coagulation in Females with Physiological or Pathological Pregnancy MUDr. Ferdinand Polák Abstract Introduction: The target of this study was to compare thromboelastography coagulation parameters in the following three groups: a) healthy pregnant women, b) healthy non-pregnant women and c) pregnant women with pathological pregnancy and also to compare it to reference limits for the common population. If appropriate, we would propose recommendations for new reference ranges for pregnant women in their third trimester. Materials and methods: Prospective observational study, comparing, by using thromboelastography, the blood samples of 60 healthy women in their third trimester of pregnancy (group GRAV) to the samples of the control group of 43 healthy non-pregnant fertile women (group NON-GRAV) and to the samples of 50 women with pathological pregnancy (preeclampsia, fetal death) in their third trimester (group PATOL). Selective percentiles were used to determine new reference limits. Results and conclusions: We found statistically significant differences between groups GRAV and NON-GRAV. Therefore, we established, based on our results, new thromboelastography reference limits for pregnant women. Coagulation changes during pathological pregnancy are less...
82

Impacts of a specialist diet on aardwolf ecology

De Vries, J.L. 07 1900 (has links)
The diet of an animal plays a fundamental role in its ecology, and the consequence of a specific diet may be more pronounced in mammals with a specialised diet that are more reliant on a specific food type. This can have a dramatic effect on its activity patterns, home range size and the interaction with heterospecifics. Investigating the diet of specialist mammals and the subsequent effects it will have on their ecology is thus vital to the management and subsequent conservation of the species, and crucial to our understanding of how the animal can survive and reproduce. In this thesis I investigate the effect that the diet of the aardwolf, a highly specialised myrmecophage, has on its ecology. Aardwolves feed predominantly on one genus of termite, Trinervoides spp., and are thus extremely dependent on the abundance and distribution of this arthropod. I firstly investigated the effect of temperature and rainfall on arthropod abundance and diversity, and further investigated the variation of arthropod abundance and diversity across the four habitat types at study site. This is one of a few studies that have been conducted on arthropod abundance and diversity in an arid environment and the findings show that in an arid environment arthropods are mainly influenced by temperature rather than rainfall. This is in contrast to studies in temperate and forest habitats where rainfall is the most important abiotic factor determining the abundance and diversity of arthropod assemblages. Habitat type still plays a major role in the abundance and diversity of arthropods, and habitat types that are more complex and diverse have both a higher diversity, and abundance of arthropods than other habitats. Due to the absence of prey items during the colder months of the year I investigated the diet of aardwolves to see if they display a switch in diet. This included an investigation into the seasonal variation of diet from a detailed scat analysis, using a newly developed method to assess scat content. The analysis of scats revealed that, contrary to previous studies, aardwolves showed no switch in diet and continued to feed on Trinervitermes. Using the data from the scat analyses and the information from the abundance and diversity of arthropods at the study site I expanded the study to investigate the functional responses of the aardwolf to change in prey abundance at the locality. Aardwolves demonstrate a Type I functional response to changes in prey abundance, a response that is normally found in plankton feeders. The expected functional response for specialist animals would be Type II response, and I propose that the Type I response seen in aardwolves is probably as a result of a limited handling time which reduces time spent foraging. The abundance of termites thus had a clear effect on the diet of aardwolves, showing that they feed on fewer when they are unavailable, and as such I investigated the effect of termite densities on home range sizes. The number of termite mounds in a home range influenced the size of the home range, and aardwolves with larger home ranges had a lower density of termite mounds. In contrast to previous studies, large overlaps between neighbouring individuals were recorded and indeed three male aardwolves shared a common den. I propose that the reason behind the overlap of home ranges is that a higher prey abundance during my study period occurred and as a consequence aardwolves did not need to defend an area to protect this resource. T. trinervoides has thus played a keystone role in driving the biology of the aardwolf and shaping many aspects of its ecology. / Thesis (PhD)--University of Pretoria, 2021. / South African Research Chair Initiative chair of Mammal Behavioural Ecology and Physiology / Zoology and Entomology / PhD / Unrestricted
83

Locoweed Poisoning in Cattle: An Overview of the Economic Problems Associated with Grazing these Ranges

Barnard, John E. 01 May 1983 (has links)
Locoweed poisoning, caused by ingestion of certain species of Astragalous and Oxytropis, has had serious economic impacts through a loss of productivity in livestock. This study has attempted to evaluate losses suffered by livestockmen grazing their cattle on areas infested with locoweed species. The results indicate a serious economic impact on these individuals. Personal interviews were carried out with five cattle ranchers faced with typical locoweed problems. These beef cattle operations were located in Utah, Wyoming, and New Mexico. All of these producers described similar problems and losses due to locoweed poisoning. Information obtained from these interviews was used to estimate a 1978 dollar loss for three ranches, running in common, and located near Park Valley, Utah. This study found the problem areas to be: (1) reduced weaning weights of calves; (2) increased requirements in the number of replacement heifers; (3) an increase in death loss; (4) reproductive problems (abortions and infertility); and (5) increased costs associated with labor and management problems. The summation of economic losses in each of these problem areas reflected a total estimated loss of $30,689.02 in 1978. To determine if locoweed poisoning had long-range effects on weight gains, a sample of 20 calves were put on a 138-day feeding experiment. Of these 20 calves, 12 had grazed a locoweed-infested area, while the remaining 8 had no access to the plant. Overall average gain of both groups was found to be nearly identical. This indicates that animals will recover with proper but, sometimes, costly management. Profitability of spraying locoweed-infested ranges with 2,4-dichlorophenoxy acetic acid (2,4-D) was determined through information supplied by the Wyoming rancher. An internal rate of return of 39.4 percent was found by using this method of locoweed control in this particular instance. Ranchers interviewed in this study estimated their losses due to locoweed poisoning to be from 30 to 40 percent reduction in profit. Although profit margins were not determined, the estimated loss of $30,689.02 found in this study would be close to their determination. With the rampant increase in operating costs which have occurred in the past decade, producers could not long endure losses of this magnitude. However, it was determined that with proper plant control and management these losses could be substantially reduced.
84

Income Adjustments form Fee and Permit Changes on Utah Cattle Ranches Using Public Ranges Yearlong

Gee, C. Kerry 01 May 1962 (has links)
Within the boundaries of Utah are approximately 52.7 million acres of land. About 41 million acres are rangeland, of which 73 percent is federally owned and 5 percent state owned (6).1 The portion owned by the Federal government is administered by the Bureau of Land Management (BLM) and the Forest Service. Most of this land is either arid or mountainous and has been used mainly for grazing in the past. IT has other uses, however, such as mining, forestry, recreation, and watersheds. Due to recent increases in population, personal income, shorter work weeks, and improved transportation facilities, these alternatives are becoming strong competitors for the use of this land.
85

Feeding Protein, Phosphorus and Energy Supplements to Beef Cows on Utah Desert Ranges

Olsen, Robert Hyrum 01 May 1959 (has links)
Many of the beef cattle in the Great Basin area are maintained part or all of the year on rangelands. Most of those going on to desert ranges for only part of the year go on during the late fall, winter, and early spring. It is estimated that 50-60 percent of the 600,000 beef cattle grazing on range lands in Utah graze on the one-fourth million acres of desert or semi-desert sometime during the year.
86

Rock Music: The Sounds of Flintknapping

Smith, Heather Noelle 13 April 2020 (has links)
No description available.
87

<b>Representation of whole-plant nutrient status with select individual leaves at multiple growth stages in maize</b><b> </b>

Brendan Jason Hanson (17112559) 10 December 2023 (has links)
<p dir="ltr">Routine testing of nutrient concentrations via plant tissue is an important component of in-season fertilizer management in maize (<i>Zea</i> <i>mays </i>L.) cropping systems. Accuracy of results are critical for nitrogen (N), phosphorous (P), potassium (K), and sulfur (S) management, yet there is little scientific guidance on which leaf to sample during mid- to late-vegetative growth stages. Additionally, the whole-plant status of each macro-nutrient may be best represented by a different leaf position due to mobility differences among nutrients. Mobility of each nutrient and allocation within the plant may also be influenced by environmental factors, management strategies, and genotype selection. Field experiments were conducted in West Lafayette and Windfall, Indiana in 2021 and 2022. The objectives were to (1) evaluate N, P, K, and S concentrations of specific leaf positions and whole plants in response to N fertilizer rate (NR), planting density (PD), and genotype (G) treatments at multiple growth stages, and (2) determine the ability of various leaf positions to predict whole-plant concentrations of N, P, K, and S across multiple NR, PD, and G environments. The West Lafayette study compared three NR treatments applied as urea-ammonium nitrate (UAN, 28-0-0) at the V5 growth stage and included (1) Control, no N applied, (2) 151 kg N ha<sup>-1</sup>, and (3) 241 kg N ha<sup>-1</sup>. The Windfall study compared two side-dress UAN rates of (1) Control, no N applied, and (2) 224 kg N ha<sup>-1</sup> at two planting densities (sub-plot) of 49,400 plants ha<sup>-1 </sup>and 89,000 plants ha<sup>-1</sup> with 4 Pioneer<sup>®</sup> genotypes (sub-sub-plot) including two historical double-cross hybrids and two modern single-crosses. Tissue sampling included the top-collared leaf and whole-plant at V8, the 8<sup>th</sup> leaf, top-collared leaf, and whole-plant at V12, and the 8<sup>th</sup> leaf, 12<sup>th</sup> leaf, ear-leaf, top-collared leaf and whole-plant at R1. Tissue N concentrations were consistently responsive to NR and PD treatments at all stages, but bottom leaves better reflected NR changes. As a mobile nutrient, N concentrations were highest in the uppermost leaf positions by R1 (ear-leaf and top-leaf), yet regressions between individual leaf and whole-plant N% were highest in the lower leaf positions (8<sup>th</sup> and 12<sup>th</sup> leaf positions). This suggested that the more likely a specific leaf was to exhibit nutrient deficiency symptoms, the better it would be at predicting whole-plant concentrations of that nutrient. Regressions between individual-leaf and whole-plant N% (modern genotypes only) increased from V8 to R1 and regressions were best with the 12<sup>th</sup> leaf position at both V12 and R1. Tissue S concentration responses to NR increased at later growth stages, and top-leaf S was a stronger reflection of whole-plant S than the 8<sup>th</sup> leaf. Despite S concentration differences among leaf positions at R1, the strength of regressions between each leaf position and whole-plant S were similar. There was no optimal leaf position to represent whole-plant S. While leaf N and S concentrations were above whole-plant concentrations, leaf P and K concentrations exhibited the opposite dynamic. There was little leaf P response to experimental treatment factors, and although regressions for leaf P versus whole-plant P concentrations were far weaker than for N, S or K, the 8<sup>th</sup> leaf position was preferred at V12 and R1 (R<sup>2</sup> of just 0.27 and 0.36, respectively). Potassium concentration response to NR was weak. However, leaf K% and whole-plant K% were highly related via regression, irrespective of NR, at all three stages. Prediction of whole-plant K was strongest with the 8<sup>th</sup> leaf at V12 and the 12<sup>th</sup> leaf at R1. In summary, optimum leaf sampling position was shown to vary with individual macronutrients and growth stages in maize. Although more research is essential, these preliminary results indicate that traditional sampling methods involving selection of the top fully-expanded leaf from V8 to silking, and the ear-leaf during post-silking stages, may not be the most reliable indicators of whole-plant nutrient status.</p>
88

Exploring Cyber Ranges in Cybersecurity Education

Beauchamp, Cheryl Lynn 01 April 2022 (has links)
According to a report from McAfee, the global cost of cybercrime for 2020 was over one trillion dollars (Smith, Z. et al., 2020). Cybersecurity breaches and attacks have not only cost businesses and organizations millions of dollars but have also threatened national security and critical infrastructure. Examples include the Ransomware attack in May of 2021 on the largest fuel pipeline in the United States and the February 2021 remote access system breach of a Florida water treatment facility which raised sodium hydroxide to a lethal level. Improving cybersecurity requires a skilled workforce with relevant knowledge and skills. Academic degree programs, boot camps, and various certification programs provide education and training to assist this need. Cyber ranges are a more recent development to provide hands-on skill training. These ranges, often virtual, provide a safe and accessible environment to improve practical skills and experience through hands-on application. They provide a training environment to identify threats, apply countermeasures, and secure data from risks separately from the organization's actual network. More and more academic programs utilize cyber ranges due to the perceived benefit of integrating them into their cybersecurity-related programs. Academic cyber ranges offer virtualized environments that support cybersecurity educators' needs to provide students with a safe, separated, and engaging environment. The purpose of my research has two components: 1) to understand who the educators are using academic-facing cyber ranges and how they are using them to support their cybersecurity education efforts, and 2) to understand how cybersecurity educators and students are motivated by using them. Specifically, my research is comprised of three manuscripts: (1) a mixed-method exploratory study of who are the educators using cyber ranges for cybersecurity education and how they are using them to create significant cybersecurity learning experiences, (2) a mixed-method study exploring the motivation of educators using a cyber range for cybersecurity education, and (3) a mixed-method study exploring student motivation participating in cybersecurity CTF competitions. The three manuscripts contribute to understanding cyber ranges in cybersecurity education. The results from my research provided insight from the users of these cyber ranges, cybersecurity educators and students. Results from my first manuscript suggested that high school cybersecurity educators are the primary users. These educators have less formal cybersecurity education and experience compared to cybersecurity educators in higher education. The data also showed that cybersecurity educators primarily used cyber ranges for teaching and learning to meet learning goals and objectives. Results from my second manuscript suggested that educators were motivated mainly by the importance of using a cyber range for cybersecurity education and for the interest-enjoyment their students experience from cyber range usage. Educators found using the cyber range made their class more engaging and relevant to their students.These educators were also confident they could use a cyber range and learn how to use it. However, those without prior experience in cybersecurity or previous experience using a cyber range shared they needed instructor-facing resources, professional development opportunities, and time to learn. Results from my third manuscript suggested that students were motivated by the importance of participating in a cybersecurity CTF competition. Many reported that participating was useful for developing professional skills and readiness. Although CTF competitions were considered difficult and stressful, students did not consider the difficulty pejorative. Many shared that challenging CTFs contributed towards the enjoyment of participating, making them a rewarding and worthwhile experience. However, students also shared that academic and team support contributed towards their confidence in competing. In contrast, those who did not report confidence, stated they lacked a team strategy or support from their academic institution. Additionally, they did not know what to expect to prepare before the competition event. Overall, the results of this dissertation highlight the importance of prior preparation for educators and student CTF participants. For educators, this prior preparation includes curriculum supporting resources such as content mapping to learning objectives and professional development opportunities that do not assume any prior knowledge or experience. For students, prior preparation includes understanding what to expect and recommendations for academic and team support. / Doctor of Philosophy / The technology era has enabled a global connectedness to attend conferences and meetings via our laptop computers while working from home. The proliferation of smart devices has also provided a means to view and communicate with visitors who ring our smart doorbells while we are not home. This interconnected network, i.e., the Internet, has altered how we pay our bills, buy our groceries, and attend classes virtually. It has also enabled cyber attacks and breaches that have contributed to identity thefts, increasing financial costs, business collapses, job losses, and even threatened national security. A cybersecurity workforce has become increasingly vital to address the need for improving cybersecurity. Thus, there is a need for academic cybersecurity programs to prepare future professionals to fill this national workforce shortfall. Consequently, more and more organizations have integrated cyber ranges as the means to provide a simulated environment for applying and developing cybersecurity-related knowledge and skills. Similar to a driving range for a golfer to practice their golf swing or a shooting range for those in law enforcement to earn their firearms qualifications, a cyber range supports efforts to provide cybersecurity training with hands-on exercises and labs to practice skills in a safe, virtual environment. My research contributes to understanding who uses cyber ranges and how they are motivated to use them for cybersecurity education. The first purpose of my research was to understand the educators who were using cyber ranges and how they were using them for cybersecurity education. More specifically, I examined their usage for alignment with a learning taxonomy to verify the usage contributed to successful and significant student learning. This understanding contributed to my research's second purpose, which explored how educators were motivated using cyber ranges. The third purpose of my study explored student motivation using a cyber range. Due to varying cyber range resources and activities, my research focused on the cybersecurity competition activity, Capture the Flag (CTF). This study provided an understanding of how students who participated in a cybersecurity CTF competition were motivated. My research demonstrates that educators and students are interested in using cyber ranges and believe using them for cybersecurity education and professional readiness is important. However, both educators and students who lack prior knowledge or experience using a cyber range or participating in a CTF shared the concern of not knowing what they do not know. PD time and instructor-facing resources that do not assume any prior cybersecurity knowledge were recommended to support educators who did not have a background or experience in cybersecurity. Students shared that although not knowing was stressful and made participating difficult, the difficulty and stress were good attributes because if the CTF were easy, it wouldn't be worth their time and would be less rewarding. Students also reported that team strategies and academic support were motivational aspects of CTF participation. Overall, educators and students were motivated using cyber ranges for cybersecurity education, but professional development and preparation resources would contribute positively to their usage.
89

Contaminants at a Shooting Range: Toxicological and Nutritional Significance to Birds and Mammals

Gonzalez, Gabriela Rae 25 August 2003 (has links)
Target shooting in the United States has become an increasingly popular sport in the last century. In addition to the large quantity of lead pellets littering range grounds and surrounding land, considerable amounts of clay target fragments cover shooting range areas as well as adjoining habitats. Polycyclic aromatic hydrocarbons (PAHs) within the target, as well as lead pellets from shotguns pose multiple threats to a variety of wildlife. To determine the effects of clay target and lead pellet ingestion on wildlife, I conducted controlled experiments on Coturnix quail exposed to clay targets in the lab, and collected wild birds and mammals exposed to lead pellets at a shooting range. The first Coturnix study determined whether quail voluntarily consumed target fragments or limestone fragments. In both fall (F=29.2, P<0.01) and spring (F=6.45, P=0.02) experiments, I found that quail consistently selected limestone fragments, but almost completely rejected clay target fragments. In the second study, quail were force-fed varying amounts of target dust on a weekly basis to simulate sporadic exposure to clay target dust. In both summer (F=1.63, P=0.23) and winter (F=0.34, P=0.8) trials, male quail did not have significant weight loss. Female quail had insignificant weight losses in summer trials (F=1.63, P=0.23) but experienced weight gains in winter trials (F=3.53, P=0.04). In the third and final Coturnix study, varying amounts of target dust were incorporated into daily feed rations to simulate frequent exposure to clay target dust. Male quail experienced weight loss in both summer (F=16.13, P<0.01) and winter (F=8.47, P<0.01) trials. Female quail also suffered weight loss in both summer (F=15.62, P<0.01) and winter (F=17.50, P<0.01) trials. Weight loss likely resulted from inadequate nutrition as opposed to target poisoning. However, because there were no biochemical analyses performed to test for PAH presence, no definite conclusions can be made. The second study focused on lead contamination in Passeriformes, perching birds, and small mammals. Seventeen of 20 birds (85%) (Passerine spp) captured at the shooting range had elevated lead levels (F=5.21, P<0.028), when compared to birds (n=20) at the control site. Nine of 26 (35%) white-footed mice (Peromyscous leucopus), trapped at the shooting range had elevated liver (F=9.78, P=0.0029) and kidney (F=22.49, P<0.01) lead levels. These results indicate that Passerine species as well as Peromyscous species around shooting ranges inadvertently consume lead, either as lead pellets, mistaking them for grit or dietary items, or through environmental sources such as water, soil, and vegetation. / Master of Science
90

TECHNICAL CAPABILITIES AND RESOURCES OF THE EXTENDED TEST RANGE ALLIANCE

Mackall, Dale A., Sakahara, Robert D. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Edwards Flight Test Range is a part of 20,000 square miles of DOD airspace (R-2508). A hypersonic air vehicle traveling above Mach 3 can easily exceed that airspace within seconds. An Unpiloted Autonomous Vehicle can exceed the airspace when flying long duration missions. To satisfy the flight-test requirements of Hypersonic Air Vehicles and Unpiloted Autonomous Vehicles, additional airspace and extended test ranges are required. The Air Force Flight Test Center and Dryden Flight Research Center at Edwards Air Force Base, California have mutual goals to support these flight test programs. To meet these goals, the Extended Test Range Alliance was formed as an engineering and operations team to satisfy program requirements in the areas of telemetry, flight termination, ground communications, uplink command, and differential global positioning systems. This paper will discuss the resources and technical capabilities available through the Extended Test Range.

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