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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.
391

Área de vida de Coryphaspiza melanotis e Cistothorus platensis no Brasil central e uma revisão sobre áreas de vida e territórios de aves na região Neotropical / Home range of Coryphaspiza melanotis and Cistothorus platensis in the central Brasil and a review of home ranges and territories of birds in the Neotropics

Fujikawa, Aline 16 August 2011 (has links)
O Cerrado é a maior, a mais rica e a mais ameaçada savana tropical do mundo, com aproximadamente 80% da sua vegetação nativa convertida em áreas modificadas, como pastagem e agricultura (Myers et al. 2000, Silva e Bates 2002, Klink e Machado 2005). É considerado um dos 25 hotspots mundiais para a conservação da biodiversidade devido à excepcional concentração de espécies endêmicas, alta riqueza de espécies e, também, por estar sofrendo uma rápida perda de vegetação nativa (Myers et al. 2000). Nele, foram registradas mais de 856 espécies de aves, das quais 4,3% são endêmicas (Cavalcanti 1999, Silva e Bates 2002, Marini e Garcia 2005, Silva e Santos 2005). O Cerrado abriga 78% das espécies de aves de campos naturais que ocorrem no Brasil, e 41% do total relacionado para a América do Sul (Vickery et al. 1999). Apesar dessa importância, grandes áreas de campos nativos foram modificadas pela expansão da agricultura mecanizada de larga escala no Cerrado (Cavalcanti 1999). O desaparecimento dos campos naturais tem causado um declínio alarmante nas populações de aves dependentes destes hábitats (Stotz et al. 1996, Cavalcanti 1999, Vickery et al.1999). A alta diversidade de aves e o considerável impacto humano demandam a priorização de pesquisas para subsidiar as ações conservacionistas no Cerrado (Cavalcanti 1999, Cavalcanti e Joly 2002, Macedo 2002). Entre elas está a geração de conhecimento sobre aspectos da história natural das espécies, informações consideradas essenciais para o desenvolvimento de medidas apropriadas para a conservação (Macedo 2002, Podulka et al. 2004, Sutherland et al. 2004, Lopes e Marini 2005). Numerosas espécies de aves que ocorrem no Cerrado ainda têm sua biologia pouco conhecida (Macedo 2002). Como exemplo têm-se Coryphaspiza melanotis e Cistothorus platensis, espécies habitantes de campos naturais no Cerrado (Tubelis e Cavalcanti 2001, Macedo 2002), esta última, inclusive, considerada espécie ameaçada de extinção (IUCN 2009). As informações disponíveis são, principalmente, de caráter geral, descritas brevemente em livros de ornitologia abrangentes, como guias de identificação de espécies (Ridgely e Tudor 1994, Stotz et al. 1996, Sick 1997, Sigrist 2006), ou em trabalhos sobre comunidades de espécies de aves (e.g. Tubelis e Cavalcanti 2001). Assim, publicações específicas e detalhadas sobre a biologia de C. melanotis e C. platensis são importantes para se compreender a biologia das espécies, assim como para disponibilizar informações importantes para estratégias de conservação e manejo (Pyke et al. 1977, Develey e Stouffer 2001, Lopes e Marini 2006). A presente pesquisa visa trazer informações pioneiras sobre a área de vida destas espécies de aves. Pesquisas sobre áreas de vida e territórios têm sido realizados em todos os continentes, principalmente com aves e mamíferos (Laver e Kelly 2008). Sherril e Case (1980) notaram que os termos área de vida e território costumam ser usados de maneira similar pela maioria dos autores, embora tenham sentidos diferentes. A área de vida é a área total na qual um indivíduo de uma espécie particular vive, buscando alimento, parceiros sexuais e abrigo (Pyke et al. 1977, Rose 1982). Por outro lado, o território é a porção da área de vida defendida contra outros indivíduos da mesma espécie (Odum e Kuenzler 1955, Podulka et al. 2004). Apesar de diversos aspectos dos estudos de áreas de vida e territórios já terem sido revisados (Schoener 1968, Worton 1987, Harris 1990, Lawson e Rodgers 1997, Powell 2000, Laver e Kelly 2008) nenhum estudo revisou publicações sobre aves de um determinado continente ou região biogeográfica. Além disso, nenhuma revisão abrangeu aspectos gerais das metodologias de estudos sobre áreas de vida e territórios de aves. Ao reunir informações de estudos de área de vida e territórios de aves realizados na região Neotropical, este trabalho pretende apontar lacunas de conhecimento e sugestões para pesquisas futuras. / In the Cerrado, native grasslands have been rapidly destroyed, leading to alarming declines in the populations of birds that rely on these habitats. Grassland species such as Coryphaspiza melanotis and Cistothorus platensis remain poorly known. The study of home ranges and territories of birds is important to understand their biology and for their conservation. The objective of this study was to study home ranges of C. melanotis and C. platensis at Parque Nacional da Chapada dos Veadeiros, central Brazil. Ten males of C. melanotis were studied between February and December 2008. The mean sizes of home ranges were 4.47 ± 1.49 ha (Minimum Convex Poligon) and 3.48 ± 1.44 ha (Kernel 95%) and varied between the studied seasons. The home ranges of all studied individuals were overlapped to those of at least three co-specifics. Small and highly overlapped home ranges can be considered a positive aspect for the conservation of C. melanotis. This is because grassland fragments and small reserves could contribute substantially for the conservation of populations through the Cerrado extension. Fourteen males of C. platensis were studied between February and December 2008. However, only five individuals were observed during all the study period. The mean sizes of their annual home ranges were 6.10 ± 2.09 ha (Minimum Convex Poligon) and 4.57 ± 1.92 ha (Kernel 95%) and varied between the seasons. These birds were quite territorial, holding territories similar to their home ranges and with low overlap with male neighbors. Our results highlight the existence of great differences between populations of C. platensis found in temperate and tropical regions. Other objective of this thesis was to review studies of home ranges and territories of birds conducted in the Neotropical region. A total of 130 scientific articles published between 1960 and 2011, with study areas in 23 countries, were revised. Home ranges were examined in 64% of the studies, while 36% of them studied territories. In 95% of the revised publications, information essential for the conduction of data collection and analyses is lacking, making impossible the replication of the studies. The study of home ranges and territories was not among the main results of numerous publications, that investigated other aspects of the biology of neotropical birds. Among the suggestions for future studies is a better description of the methodologies.
392

An in vivo improvement of range of motion in shoulder contractures with relaxin in animal models

Okajima, Stephen Michael 13 July 2017 (has links)
INTRODUCTION: Arthrofibrosis, which occurs in a substantial portion of the population, is a pathologic accumulation of scar tissue that presents in patients as a painful decrease in joint range of motion. Since an individual’s quality of life can be significantly impacted by arthrofibrosis and because there are limitations in current treatments, this thesis focuses on examining the use of the hormone relaxin to alleviate shoulder arthrofibrosis. METHODS: A set of 20 Sprague Dawley rats were given secondary shoulder contractures and separated into groups to examine the efficacy of relaxin using intravenous delivery, intra-articular delivery, and different treatment frequencies. The differences across groups were examined through mechanical range of motion testing as well as histologic sampling. RESULTS: Multiple doses of intra-articular injections of relaxin showed a complete return to the normal range of motion (P < 0.01) when compared with the surgical control, whereas other delivery methods and frequencies failed to show meaningful improvements. This was further confirmed in histologic analysis through the lack of fibrotic adhesions within the capsular space after multiple intra-articular relaxin treatments when compared with the surgical control. DISCUSSION: Although significant improvements to range of motion were seen after multiple doses of intra-articular relaxin, potential tissue degradation was also observed within the joint space after histologic examination. Further research is necessary to fully understand the proper dosing needed to avoid potential negative side effects caused by excess use of relaxin.
393

Structural Geology of the Central Part of Clarkston Mountain, Malad Range, Utah

Green, Douglas A 01 May 1986 (has links)
The central part of Clarkston Mountain is located in northcentral Utah in the southern part of the Malad Range. It is northwest of Clarkston, Utah. The mapped area measures 2.5 mi. in the north-south direction and 6.5 mi. in the east-west direction. It is within the Basin and Range Province. The Ute Formation of Middle Cambrian age is the oldest exposed stratigraphic unit. Other Cambrian units, in ascending order, are: Blacksmith Formation, Bloomington Formation, Nounan Formation, and St. Charles Formation. These units consist predominantly of limestone, dolostone, and shale. Units of Ordovician age include the Garden City Formation and the Swan Peak Formation. They consist of limestone and orthoquartzite, respectively. The youngest Paleozoic unit is the Fish Haven-Laketown Formation of Ordovician-Silurian age. It is dolostone. Units of Quaternary age include colluvial deposits, Lake Bonneville Group, and alluvial deposits. West-dipping, low-angle normal faults generally trend north and northwest. They were originally thrust faults formed during regional compression. A bedding-plane thrust fault separates the Bloomington and Nounan Formations. Later reversed movement on the west-dipping, low-angle thrust faults changed the stratigraphic relationships across these faults to those characteristic of normal faults. High-angle normal faults trend northwest, north, and northeast. Major normal faults extend along the western and eastern sides of Clarkston Mountain and are responsible for the present topographic relief. The structural features of the mapped area are the result of two major tectonic events. The Sevier orogeny produced eastward directed thrust faults. It began in Late Jurassic and ended in early Eocene. Basin and Range normal faulting caused reversed movement on west-dipping thrust faults, formed by the Sevier orogeny, and also produced many high-angle normal faults. It began in early Eocene and has continued into historic time in the region.
394

Potential For Cattle Grazing on Sheep Range in Southwest Utah

Gutierrez-Garza, Jose Salvador 01 May 1978 (has links)
A study was conducted on pastures grazed by sheep in late winter at the Desert Experimental Range in southwest Utah. Estimates of plant cover and herbage production were obtained in 1977 and used to examine longterm trends in the vegetation. The nutritional value of the six most important species of the area was assessed by chemical analysis. In addition, a management strategy was developed for obtaining some utilization of the range during the spring and summer months without affecting the traditional winter use by sheep. Long-term records (since 1937) in cover suggest a modest increase in grasses and a decrease in shrub cover. But there are insufficient data to infer range condition and trend. Long-term herbage production data (since 1938) show a substantial increase in annual species over the last twenty years. The year-to-year variability is very high, apparently depending on the prevailing climate conditions. Grass production was less variable than shrub production. No significant difference (P<.05) in crude protein content was found between shrubs and grasses from April to September, which contrasts with the later decline in nutritive value of grasses during the winter. Phosphorus content was significantly higher in shrubs than in grasses, but the high lignin content of shrub forage made its digestibility significantly lower than for grasses. Based on the nutritional analysis of forage and long-term records of climate and plant production, a management strategy was devised to make more efficient use of the salt-desert shrub vegetation. Climatic conditions will favor good forage production about four years out of ten. Perennial grasses, annuals, and winterfat (Ceratoides lanata) showed better response to favorable climatic conditions than the other species. It is proposed in this study that, in these years of high production, the range could be used by cattle in the spring or summer, and thereby al low occasional resting of mountain summer pastures. Such opportunistic summer grazing on the desert should not be detrimental to winter sheep grazing, but the plan would need to be field-tested on an experimental or trial basis to evaluate ecological responses to increased livestock use.
395

Scanning Electron Microscopic (SEM) Studies on Range Grasses and Their Resistance to Black Grass Bugs

Ling, Yun-Hwa 01 May 1982 (has links)
Large populations o+ black grass bugs, Labops hesperius Uhler, have been observed on extensive acreages o+ range lands. These bugs cause severe damage to the range grasses, lowering their palatability and productivity. This study was to determine whether morphological differences among breeding lines o+ grass species or interspecific hybrids could be correlated with the feeding behavior o+ black grass bugs. I+ so, plant breeders should be able to develop resistant cultivars. To explore this possibility, cultivars and synthetics o+ range grasses, representing the genera, Agropyron, Dactylis, Phalaris and Poa, were exposed to di++erent instar stages was examined under a scanning electron microscope. Leaf pubescence (trichomes) varied in density and size and appeared to be associated with resistance of plants in the genera, Agropyron, to the Labops nymphs (instar stages II and III> but had no relation with the feeding behavior of adult black grass bugs. Plant leaves of the general, Dactylis and Phalaris, were smooth (few and small if any trichomes> and were the least preferred of any of the grasses by all stages of the bugs. Trichomes on leaves of other genera were varied in density and size. Based on percent damage, preference by the nymphs was for the species with intermediate sized trichomes. The adult bugs showed no discrimination in their feeding behavior. Field grown plants developed more trichomes per unit leaf area and appeared to have thicker surface waxes than the same species grown in the greenhouse. For this reason, nymph feeding habits may be different in the field than in the greenhouse. Future studies should perhaps investigate (1) first stage nymph activity on field plants and (2) palatability and/or chemical differences of the grasses.
396

Home Range and Habitat Use of Santa Rosa Island Foxes (Urocyon littoralis santarosae)

Drake, Elizabeth Marie 01 March 2013 (has links)
Island foxes (Urocyon littoralis) are currently listed as federally endangered on four of the six Channel Islands to which they are endemic. The Santa Rosa Island (SRI) population declined by 99% during the 1990’s due to non-native golden eagle (Aguila chrysaetos) predation and is currently the lowest fox population (~280) and density (0.86 foxes/km2) of any of the Channel Islands. The goals of this study were to assess new miniaturized GPS technology and to quantify home range and habitat use of the SRI population. This is only the second use of Global Positioning System (GPS) collars on Channel Island foxes and provides essential baseline data for the recovering population. These results can be used to guide management decisions and future habitat restoration efforts after the recent removal of non-native ungulates. In fall 2009, 14 GPS collars were deployed on male foxes on the east side of SRI. Nine collars and three remote download datasets were recovered in 2010. The collars’ battery life was 40% lower than expected at an average (±SE) of 16.5 ± 1.7 weeks but had high performance in precision and fix rate. Collars yielded an average of 347 ± 33 locations with a fix rate of 82.3% ± 2.1% and 88% of locations categorized as high precision. From these data, 95% minimum convex polygon (MCP) home ranges and 95% kernel density isopleth (KDI) home ranges were created. The average 95% MCP home range size was 3.39 ± 0.59km2 and the area of overlap with adjacent home ranges had a median of 5.3%. The average 95% KDI home range size was 3.82 ± 0.68km2 with a median overlap of 6.0%. These home range sizes are almost triple the size reported in other island fox studies, likely due to the low fox densities in the recovering SRI population. Habitat analysis was performed using KDI home ranges and a Euclidian distance analysis (EDA) method to assess habitat selection within the study area, the home range and the core area. Results showed selection for lupine within the study area, which no previous studies have documented. There was no significant habitat selection within the home ranges or core areas. Foxes selected for valley bottom topography and for bare and grassland habitat at night. One shortcoming of EDA is that its reliance on random points for determining second order selection can lead to unused areas being identified as selected habitat. The lack of significant selection within home ranges and core areas may be attributed to small sample sizes, use of male foxes only and the timing of the study in relation to fox reproductive biology. I recommend further investigation in the use of lupine habitat and associated resources through prey inventory studies to further assess these findings. When densities reach historic levels of 4 foxes/km2, follow up studies should be conducted to reassess home range size, overlap and habitat use to determine if home range sizes have decreased and overlap has increased. Future studies should incorporate spring and summer seasons and females to determine if foxes select a particular habitat within the core area during denning and pupping periods.
397

Volcanic Glass as a Paleoenvironmental Proxy: Comparing Preparation Methods on Ashes from the Lee of the Cascade Range in Oregon, USA

Carlson, Tessa Boe 06 July 2018 (has links)
Deuterium ratios (δD) of hydrated volcanic glass have been used to reconstruct paleoenvironments, although the reliability and proper sample preparation protocol have been debated. In this study, hydrated volcanic ash samples from the lee of the Cascades were prepared using two separate methods. Method 1 involves sonicating and rinsing samples with hydrochloric acid (HCl) followed by hand-selection of glass shards (125-212µm). Method 2 requires hydrochloric acid (HCl) and hydrofluoric acid (HF) abrasion as well as heavy liquid separation of shards (70-150µm). Method 2 produced more consistent results with decreased intra-replicate variability in both water content (-0.92 wt. %) and deuterium values (-2.5‰ δD). Method 2 δD values of ≥99% isotropic glass were also 2.5-10 % more negative relative to Method 1 values, with an increasing discrepancy with age (3.68-32.66 Ma). Method 2 results suggest volcanic glass did not re-equilibrate with modern water, based on 1) < 2‰ discrepancies between samples of the same ash flow taken from unique sample localities and 2) a ~20‰ difference between samples of different ages (~8 Ma apart) from the same locality. These results support the specified use of HF abrasion and heavy liquid separation on 70-150 µm glass shards to minimize the impact of contaminants on reconstructed paleowater δD values.
398

Factors influencing parental care and home range size of a monomorphic species, the Red-headed Woodpecker (Melanerpes erythrocephalus)

Walter, L. Abigail 01 January 2019 (has links)
Parental care in animals can be costly and is shared between both parents in many bird species. Not surprisingly, most studies of how parental care is shared between the sexes are in sexually dimorphic species, and much less in known about sexually monomorphic species where sex cannot be determined in the field. This has prevented a full understanding of parental care behaviors – which are intrinsically linked to fitness – in species such as the Red-headed Woodpecker (Melanerpes erythrocephalus) that is experiencing population declines throughout much of its range. In this study we assessed whether Redheaded Woodpecker brooding time, nestling provisioning rates, and nest cleaning rates vary as a function of parent sex, habitat type (savanna and closed canopy forest), brood size, nestling age, temperature and/or date. We recorded and analyzed 128 hours of high-quality video from 21 broods at Fort A.P. Hill, Virginia where this species is relatively abundant. We captured and color-banded Red-headed Woodpeckers, taking breast feather samples for genetic sexing, and determined brood size and chick age of nests using an extendable pole camera. Using generalized linear mixed models, we found the best predictor of nestling provisioning was an interaction between chick age and date; older chicks were fed more frequently in early summer (before 7 July) compared to late summer. The seasonal reduction in provisioning could be related to a reduction in resource availability, but whether or not provisioning in later nests affects nestling survival warrants further study. We found chick age and parent sex to be the best predictors in brooding models, with females brooding more when chicks are less than 10 days old and males being the only parent to enter the cavity after 10 days. Additionally, males almost exclusively remove fecal sacs from nests, highlighting an observational method to determine sex of breeding adults in the field. Such division of reproductive roles is similar to what is known for dimorphic woodpecker species and likely indicates energetic constraints due to the need for high parental investment from both sexes. Parental care is inextricably linked with habitat quality and home range size. Parents will travel to obtain the resources necessary to provision their young, and larger home ranges during the demanding nestling provisioning stage may indicate increased effort resulting from fewer available resources near the nest. We estimated home range sizes of 25 breeding adult Red-headed Woodpeckers using PinPoint GPS tags and 95% kernel density estimates (KDEs) with plug-in smoothing factors. We modeled the effects of habitat, sex, nest stage, date, and distance to nearest neighbor on home range estimates. Red-headed Woodpecker males have larger home ranges than females, and late summer home ranges are smaller than those measured before 7 July. More study is needed to determine if sex or date is a stronger factor on home range, given our naive sampling which resulted in more females sampled in late summer and observations that did not continue to the end of the breeding season (late August). Since we found date to be an influential factor to both provisioning rate and home range size, it is possible that seasonal resource changes are an important, unstudied factor related to nationwide declines of this species.
399

Geology of the Southern Part of Wellsville Mountain, Wasatch Range, Utah

Gelnett, Ronald H. 01 May 1958 (has links)
Wellsville Mountain is 10 miles west of Logan, Utah, at the northern extremity of the Wasatch Range. Paleozoic rocks forma northeast-dipping homocline bounded in part by northwest-trending high-angle faults and cut by a series of northeast-trending high-angle faults. A major transverse fault, with a stratigraphic displacement of 4,500 feet, divides the mountain into two distinct blocks. The rock units of the area are comparable to those of the Logan quadrangle immediately to the east. Pre-Cambrian rocks crop out in Box Elder Canyon, just east of Brigham City, and are overlain by at least 20,000 feet of northeast-dipping Paleozoic rocks of every period except possibly the Permian. The Beirdneau sandstone member of the Jefferson formation, is tentatively correlated with that of the upper Devils Gate limestone of central Nevada. About 6,600 feet of the Oquirrh formation of Pennsylvanian age is exposed near the northern end of Wellsville Mountain. The presence of Desmoinesian fusulinids at the base of the Oquirrh and upper Virgilian fusulinids throughout the interval from 1,000 to 2,000 feet above its base indicates an absence of Lower Pennsylvanian rocks and suggests that the upper 4,400 feet may be in part Permian. Mesozoic rocks are not found in the area. The Wasatch formation and Salt Lake group of Tertiary age crop out in the foothills at the northern end of Wellsville Mountain. Two fault systems are recognized in the area. The northeast-trending high-angle transverse faults of Laramide age and the north-west-trending high-angle bordering faults are Basin and Range age.
400

The Effects of Policy Development and Organizational Structure on the Performance of Range Livestock Development Projects in Africa

Perrier, Gregory Karl 01 May 1991 (has links)
Range professionals are frequently involved in the arranagenent of range development projects, both dornesticalY and internationally. '!he success record of such projects has been uneven, particularly for projects in deveoloping nations. '!he objective of this study was to provide ~e specialists a better understanding of potential management obstacles and barriers to success. '!his is accomplished through an examination of the management of three AID-funded pastoral development proj ects in Africa: the Tanzanian Masai Livestock and Range Management Project, the Sanali Central Rangelarrls Development Project, and the ~tho Lard Conservation and Range Development Project. 'Ibe study examined the effects of two ilTIportant aspects of proj ect management, organizational structure and goal and strategy development, on project perfonnance. Firrlings indicated two major themes: project perfonnance is improved by actions that 1) increase flexibility and 2) result in appropriate strategies. Flexibility was increased by support from politically pcMerful institutions (e.g., pcMerful ministries, donors, etc.), ability to m:xlify internal stnlctures and external linkages to other organizations during implementation, ability to m:xlify strategy during implementation, devolution of operational decision-making to field levels, allowing field staff control over the resources needed to implement their activities, and participation in decision-making by pastoralists. Appropriate strategies are those having a high congruence with the interests of key actors (i. e., donors, national ministries, local administrators, pastoralists) , with pastoral household goals and extant production strategies, with the resources and capabilities locally available, and with inten1al structures and external linkages

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