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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.
21

Fjällfåglar : En jämförande studie från dal till topp i ett nordligt och sydligt svenskt fjäll

Zackrisson, Kristian January 2011 (has links)
Title: Mountain birds – a comparative study from valley to mountaintop in a northern and southern Swedish fjeld   Author: Kristian Zackrisson   Abstract Main aim in this study was to increase the knowledge about birds in the Swedish mountain area. Three questions were asked: 1) Which bird species can be found during the breeding season along a low mountain slope from a forested valley to a mountaintop with bare mountain environment? 2) Do the number of species and individuals differ in different elevation zones? 3) Is the composition of bird species along a low mountain slope the same in the Kebnekaise mountains inLaplandand the Grövelsjön mountains in Dalarna? Bird census in two study sites located in the Kebnekaise mountains and the Grövelsjön mountains and subsequent analysis of the results from the bird census was the main parts in this study. Totally 20 bird species were found along a low mountain slope in the Kebnekaise mountains. In a lower elevation zone below the forest boundary there was 16 bird species and 509 individuals observed. 6 bird species and 65 individuals were registered in an upper elevation zone above the forest boundary. The lower elevation zone indicated a higher biodiversity for birds compared to the upper elevation zone. Bird species composition varied between the two study sites. Five species that had been observed in the Kebnekaise mountains where not found in the Grövelsjön mountains which instead had six species that were not found in the Kebnekaise mountains. Compared to other studies the 20 observed bird species are some of several species in the specific area. The higher biodiversity in the lower elevation zone can be related to declining temperature by elevation gradients. Previous bird censuses indicate that the bird species observed in the Kebnekaise mountains also can be found in the Grövelsjön mountains.
22

Evaluation Of An Education Intervention For The Staff On The Head Of The Bed Elevation In The Pediatric Intensive Care Unit

Johnson, Randall 01 January 2007 (has links)
Elevating the head of bed (HOB) reduces risks for aspiration and ventilator associated pneumonia (VAP) in the adult population. Educational interventions have resulted in improvements in achieving a target HOB elevation of 30° in adults. Limited research has addressed this intervention in the pediatric intensive care unit (PICU). The aim of this study was to determine if an educational intervention for the PICU staff would result in improvement in the HOB elevation in the PICU. Four research questions were studied: 1) What is the common practice related to the elevation of the HOB in the PICU? 2) Is there a difference in the mean HOB elevation before and after an education intervention? 3) Is there a difference in the percent of time the HOB is at or above 30° after the intervention? and 4) What factors influence HOB elevation in the PICU? A quasi-experimental, pre, and post measurement, with nonequivalent comparison group design was used. The angle of the HOB elevation was measured with the “Pitch and Angle Locator” (PAL) (Johnson, Mequon, WI). Baseline measurements (n = 99) were obtained for patients admitted to a PICU at various days and times over a 2-week period. An educational intervention was done for the staff members in the PICU, with a focus on the importance of keeping the HOB up and strategies for measuring the HOB elevation. Posters to reinforce the information were placed on the unit. Post-intervention, measurements (n = 98) were obtained for another 2-week period. At the time of data collection, staff members caring for the PICU patients were asked to provide responses for what influenced them to place the patient at the documented HOB elevation. Children were older in the post-intervention group than in the pre-intervention (8.8 yrs, vs. 3.7, yrs, respectively, t = -6.67, df = 195, p= .000). The children also weighed more in the post-intervention group than in the pre-intervention (32.0 kg vs. 19.7 kg, respectively, t = -4.19, df= 195, p = .000). The mean HOB elevation was 23.5° before the intervention. After the intervention, the mean HOB increased to 26.5° (t = -1.19, df 195, p = .033). For ventilated patients, the mean HOB elevation went from 23.6° to 29.1° (t = -3.25, df 95, p= .001), and for patients mechanically ventilated and in an adult bed, the mean increased from 26° ± 7.89°, pre- intervention to 30° ± 8.59° postintervention (t = -1.80, df 63, p = .038). The percent of the time the measures were greater than 30° increased from 26% to 44% pre- and post-intervention respectively (χ2 6.71, df 1, p= .005). Responses (n = 230) related to the factors that influenced positioning were categorized as follows: physician order (3%), safety (7%), found this way (11%), therapeutic intervention (16%), comfort (24%), and patient condition (39%). An educational intervention can impact the practice of elevation of the HOB in a PICU, thus decreasing the risks of developing aspiration and VAP. Although the mean HOB increased statistically, the HOB was less than 30° in more than half of the post intervention measurements, indicating the need for ongoing reinforcement of the education. The PAL device was a new, reliable method for recording HOB elevation in both adult beds and cribs. Follow-up research is needed to determine if these gains in HOB elevation have been sustained over time and their impact on VAP.
23

Terrain elevation determination using a microprocessor controlled vector map

Goosen, Richard F. January 1985 (has links)
No description available.
24

Neonatal testosterone treatment affects the paw elevation of the Mongolian gerbil (Meriones unguiculatus)

Robertson, Rohan 08 1900 (has links)
<p> The present thesis reports an experiment that investigated the phenomenon of asymmetric paw elevation in the tripedal stance of the Mongolian gerbil, and tested the Geschwind-Galaburda extra-genetic theory of human handedness. Neonate gerbils of both sexes were injected with testosterone propionate during the "critical" period of brain development. They were then assessed for asymmetry in eye opening, for anogenital distance, and for paw elevation and scent marking before and after puberty. Eye opening asymmetry was not affected by treatment. Paw elevation was affected by treatment, with treated gerbils of both sexes displaying more right elevations before and after puberty than untreated gerbils. Control females displayed systematic patterns in paw elevation before and after puberty. Adult gerbils in all conditions displayed more consistency in paw elevation than young gerbils. Anogenital distance was increased with treatment, but only in the females. Adult scent marking behavior was marginally reduced with treatment, but only in the males. Results are interpreted within the Geschwind-Galaburda theory of handedness, and the hormonal basis of paw elevation is discussed. </p> / Thesis / Master of Science (MSc)
25

Temporal advances in the peak and end of flowering in Streptanthus tortuosus

Indraganti, Lahari 25 September 2024 (has links)
Climate change is causing shifts in the phenology (timing of life events) of many organisms with consequences such as changes in species interactions and community composition. Owing to the large elevational and latitudinal gradients in its distribution, the native California wildflower, Streptanthus tortuosus (shieldplant) is a great model organism for studying the impacts of climate change. Few studies have looked at temporal shifts in the onset, peak, and end of flowering. Herbarium specimens and local historical climate data were used to make inferences about the temporal shifts of flowering phenology and the impacts of rising mean annual temperature and minimum monthly temperature on flowering phenology. Across the 114 years (1894- 2010) sampled, low elevation specimens (up to 1000 m) were the most sensitive to phenological shifts with their peak flowering advancing by 19 days. The end of flowering in low elevation plants advanced by 17 days. Furthermore, the data demonstrate that increasing temperatures correlated with earlier flowering times for all specimens, particularly at low elevations. Plants at higher elevations displayed smaller shifts in flowering timings. Taken together, these results suggest that climate change is likely causing shifts in the reproductive phenology of S. tortuosus. Understanding these impacts will enable us to better understand and predict the plant’s ability to adapt and persist in California as it faces new and increasingly variable environmental conditions in the future.
26

On guided bone reformation in the maxillary sinus to enable placement and integration of endosseous implants. Clinical and experimental studies.

Cricchio, Giovanni January 2011 (has links)
Dental caries and periodontal disease are the major causes for tooth loss. While dental caries commonly involve the posterior teeth in both jaws, the teeth most commonly lost due to periodontal problems are the first and second molars in the maxilla. As a consequence, the upper posterior jaw is frequently edentulous. Implant therapy today is a predictable treatment modality for prosthetic reconstruction of edentulous patient. Insufficient amounts of bone, due to atrophy following loss of teeth or due to the presence of the maxillary sinus, can make it impossible to insert implants in the posterior maxilla. During the 1970s and 1980s, Tatum, Boyne and James and Wood and Moore first described maxillary sinus floor augmentation whereby, after the creation of a lateral access point, autologous bone grafts are inserted to increase crestal bone height and to create the necessary conditions for the insertion of implants. This surgical procedure requires a two-stage approach and a double surgical site: first, bone is harvested from a donor site and transplanted to the recipient site; then, after a proper healing period of between 4 to 6 months, the implants are inserted. This kind of bone reconstruction, even if well documented, has its limitations, not least in the creation of two different surgical sites and the consequent increased risk of morbidity. In 2004, Lundgren et al. described a new, simplified technique for the elevation of the sinus floor. The authors showed that by lifting the sinus membrane an empty space was created in which blood clot formations resulted in the establishment of new bone. The implants were placed simultaneously to function as “tent poles”, thus maintaining the sinus membrane in a raised position during the subsequent healing period. An essential prerequisite of this technique is to obtain optimal primary implant stability from the residual bone in the sinus floor. An extremely resorbed maxillary sinus floor, with, for example, less than 2-3 mm of poor quality residual bone, could impair implant insertion. The aims of the present research project were (i) to evaluate the donor site morbidity and the acceptance level of patients when a bone graft is harvested from the anterior iliac crest, (ii) to evaluate implant stability, new bone formation inside the maxillary sinus and marginal bone resorption around the implants in long term follow up when maxillary sinus floor augmentation is performed through sinus membrane elevation and without the addition of any grafting material, (iii) to investigate new bone formation inside the maxillary sinus, in experimental design, using a resorbable space-maker device in order to maintain elevation of the sinus membrane where there is too little bone to insert implants with good primary stability. In Paper I, 70 consecutively treated patients were retrospectively evaluated in terms of postoperative donor site morbidity and donor site complications. With regard to donor site morbidity, 74% of patients were free of pain within 3 weeks, whereas 26% had a prolonged period of pain lasting from a few weeks to several months. For 11% of patients there was still some pain or discomfort 2 years after the grafting surgery. Nevertheless, patients acceptance was high and treatment significantly improved oral function, facial appearance, and recreation/social activities and resulted in an overall improvement in the quality of life of formerly edentulous patients. In Paper I and III, some differently shaped space-making devices were tested on primates (tufted capuchin - Cebus apella) in two experimental models aimed at evaluating whether a two-stage procedure for sinus floor augmentation could benefit from the use of a space-making device to increase the bone volume and enable later implant installation with good primary stability, without the use of any grafting material. An histological examination of the specimens showed that it is possible to obtain bone formation in contact with both the Schneiderian membrane and the device. In most cases the device was displaced. The process of bone formation indicated that this technique is potentially useful for two-stage sinus floor augmentation. The lack of device stability within the sinus requires further improvement in space-makers if predictable bone augmentation is to be achieved. In Paper IV, a total of 84 patients were subjected to 96 membrane elevation procedures and the simultaneous placement of 239 implants. Changes of intra-sinus and marginal bone height in relation to the implants were measured in intraoral radiographs carried out during insertion after 6 months of healing, after 6 months of loading and then annually. Computerised tomography was performed pre-surgically and 6 months post-surgically. Resonance frequency analysis measurements were performed at the time of implant placement, at abutment connection and after 6 months of loading. The implant follow-up period ranged from a minimum of one to a maximum of 6 years after implant loading. All implants were stable after 6 months of healing. A total of three implants were lost during the follow-up period giving a survival rate of 98.7%. Radiography demonstrated an average of 5.3 ± 2.1 mm of intra-sinus new bone formation after 6 months of healing. RFA measurements showed adequate primary stability (implant stability quotient 67.4 ± 6.1) and small changes over time. In conclusion, harvesting bone from the iliac crest could result in temporary donor site morbidity, but in 11% of patients pain or discomfort was still present up to 2 years after surgery. However, patient satisfaction was good despite this slow or incomplete recovery, as showed by the quality of life questionnaire. Maxillary sinus membrane elevation without the use of bone grafts or bone substitutes results in predictable bone formation both in animal design, where the sinus membrane is supported by a resorbable device, and in clinical conditions, where the membrane is kept in the upper position by dental implants. This new bone formation is accompanied by a high implant survival rate of 98.7% over a follow-up period of up to 6 years. Intra-sinus bone formation remained stable in the long-term follow-up. It is suggested that the secluded compartment allowed bone formation in accordance with the principle of guided tissue regeneration. This technique reduces the risks of morbidity related to bone graft harvesting and eliminates the costs of grafting materials.
27

Inspiration: Examining Its Emotional Correlates and Relationship to Internalized Values

Jennings, David, II 05 November 2012 (has links)
The study of inspiration as a psychological construct has received little empirical attention to date. In the present dissertation, I review the empirical literature on inspiration and present a theoretical model and definition of inspiration. In two studies, I tested a Value-Congruent Model of Inspiration and my proposed definition. In Study 1 (N = 134), I explored inspiration’s emotional correlates and tested whether individuals experience greater inspiration if the inspirational content is concordant with individual meaning and values. As predicted, state inspiration was positively related to state levels of admiration, awe, and elevation, and value-congruent stimuli significantly predicted self-reported experiences of inspiration. In Study 2 (N = 173), I replicated these results and tested whether value-congruent inspiration would predict behavioral intentions and volunteering behavior toward environmental preservation. The adapted measure of self-concordance for internalized values did not yield the predicted results. However, one’s level of commitment to the environment predicted willingness to sacrifice for the environment, which was partially mediated by state inspiration.
28

Metodologia de elaboração automatizada de modelo digital de elevação e ortofoto em média e pequena escala. / Methodology of automatic digital elevation model and ortophotos construction to medium and small scales.

Idoeta, Ivan Valeije 19 November 2007 (has links)
O presente trabalho propõe uma metodologia para a elaboração de modelos digitais de elevação e ortofotos, em média e pequena escala, de maneira automática, utilizando correlação de imagens digitais, a partir de fotografias aéreas métricas. Aborda conceitos básicos de Fotogrametria e correlação de imagens digitais, e lança o conceito da janela epipolar como ferramenta auxiliar na busca e correlação. Estas janelas permitem obter a máxima correlação simultânea entre duas ou mais imagens, como também a varredura em qualquer direção. Isso torna bastante robusto o método de elaboração dos produtos propostos. Esta metodologia foi implementada em um caso prático onde se utilizou uma cobertura aerofotogramétrica em escala 1:25.000. Os produtos foram validados, a partir de elementos de referência retirados de outra cobertura em escala 1:5.000. As precisões atenderam os requisitos do PEC Classe A para a escala 1:2.500 em planimetia, e intervalos de curvas de nível de 5 metros de eqüidistância, em altimetria. / This work presents a methodology for the production of digital elevation model and orthophotos on medium and small scales, with an automatic manner, using the concepts of digital image correlation. It presents basic fundamentals of photogrammetry and digital image correlation, and launches the concept of epipolar window like an auxiliary search and correlation tool. These windows allow the simultaneous multiple image correlation, in different direction scanning. This makes quite robust the production method of the proposed products. This methodology was implemented in a practical case, where 1:25.000 scale photogrammetric images were used. The products were validated using a 1:5.000 scale coverage as reference. The accuracy and precision achieved are into the Brazilian Cartography Standards as \"Classe A\" for the 1:2.500 scale, in planimmetry, and 5 meter contour lines interval in altimetry.
29

A Digital Elevation Model of the Lövåsen Esker

Bring, Hedda January 2007 (has links)
<p>The threats imposed by the ongoing climate change become successively more clear. In the municipality of Sandviken the possible rise in water level in the lake Storsjön might cause major problems. This study aims to produce an elevation model over one of the threatened areas so that the effect of different water levels in the lake can be studied in the future.</p><p>The area of study consists of an esker cutting straight through the lake Storsjön. The area is densely populated and the size is about 13 hectares.</p><p>Measurements were performed, both with GPS, utilizing Network-RTK, and with total station. The formations of the ridge were captured by following the breaklines with a point density of 225 points/ha as an intended goal.</p><p>The GPS measurements were transformed into the local coordinate system of Sandviken municipality. The measured coordinates for six control points were compared to the true coordinates. The fit was not perfect, so a Helmert transformation was performed on the plane coordinates. The accuracy of the measurements was below 50 mm after the transformation. Net adjustments in plane and height were performed on the total station measurements. The error ellipses for the station points varied from 2 to 44 mm. The over all point density achieved was 274 points/ha.</p><p>Two elevation models were created, one Triangular Irregular Network (TIN) and one interpolated model using a kriging interpolation. Contour lines from both models were produced and compared with each other. The TIN creates a more angular surface and therefore the contour lines are not as smooth as in the interpolated model. Both models showed good resemblance compared with the original data.</p> / <p>Problem relaterade till klimatförändringar blir alltmer uttalade. I Sandvikens kommun kan problem uppstå om vattennivåerna i Storsjön stiger. Syftet med det här examensarbetet var att skapa en höjdmodell över ett av de utsatta områdena för att effekter av en eventuell vattennivåhöjning skall kunna studeras i framtiden.</p><p>Området består av en rullstensås som sträcker sig rakt igenom Storsjön. Området är tättbefolkat och ca 13 hektar stort.</p><p>Mätningarna utfördes med både GPS och totalstation. Vid GPS-mätningarna utnyttjades Nätverks-RTK. Åsens formationer fångades genom att följa brytlinjer med en estimerad punkttäthet på 225 punkter/ha.</p><p>GPS-mätningarna transformerades till Sandvikens lokala koordinatsystem. De mätta koordinaterna för sex kontrollpunkter jämfördes med de sanna koordinaterna. Eftersom de mätta värdena inte passade in perfekt så utfördes en Helmerttransformation av plankoordinaterna. Noggrannheten på mätta värden var inom 50 mm efter transformationen. Nätutjämningar i plan och höjd gjordes på totalstationsmätningarna. Felellipserna för stationspunkterna varierade mellan 2 och 44 mm. Den sammanlagda punkttätheten uppgick till 274 punkter/ha.</p><p>Två höjdmodeller framställdes, en TIN-model (Triangular Irregular Network) och en interpolerad model där interpolationsmetoden kriging användes. Höjdkurvor framställda från respektive modell skapades och jämfördes med varandra. Ett TIN ger en mer kantig yta vilket återspeglas i höjdkurvorna som inte är lika jämna som de från den interpolerade modellen. Båda modellerna visade god överensstämmelse med originaldata.</p>
30

Evolution of Dioecy in Echinocereus coccineus: Relative Influence of Pollinators, Resources and Elevation over Multiple Spatial Scales

Scobell, Summer Ann 21 April 2008 (has links)
"Why have separate sexes?" is a fundamental question in biology and has been investigated intensively since Darwin first proposed two hypotheses: Separate sexes evolve 1) to avoid detrimental effects of self-fertilization or 2) to improve allocation of scarce resources to each sex's reproductive function. In animal-pollinated plants dioecy is hypothesized to be favored when small, generalized pollinators predominate because they increase self-fertilization rates of plants. I concurrently tested Darwin's hypotheses using Echinocereus coccineus (Cactaceae). I found, as predicted, when specialized pollinators (hummingbirds) were excluded from plants and only generalized pollinators (bees) visited, selfing rates of plants increased 238%. High selfing rates produced by bees, along with high levels of inbreeding depression in E. coccineus populations, were sufficient to select for dioecy, even in absence of any reallocation of resources by the plants. Hummingbirds may also maintain high levels of gene flow among E. coccineus populations: populations blooming synchronously with the hummingbird migration had lower FST values (i.e. less genetic divergence) than asynchronously blooming populations. Population genetic data also suggest frequency of dioecious populations should be negatively correlated with both hummingbird abundance and elevation. Structural equation models of effects of hummingbird abundance, elevation and annual rainfall (resources) on dioecy across the range of E. coccineus supported this hypothesis. All predictor variables were either directly or indirectly negatively correlated with dioecy. Only models with hummingbird abundance as a direct predictor of dioecy significantly fit the data. Darwin's first hypothesis was again supported: as hummingbird abundance declines (and selfing rates increase), the incidence of dioecious populations increases. Finally, to determine how changes in pollinator type may be globally influencing the evolution of dioecy, I conducted a literature survey of studies noting changes in pollinator types along elevation gradients and compared these to studies of dioecy along elevation gradients. The abundance of specialized insect pollinators declines with elevation, often leaving only generalized pollinators at the highest elevations: Proportion of dioecious species in communities increases accordingly with elevation. I propose elevation may be useful as a worldwide predictor of dioecy because it effects pollinator community composition and amount of inbreeding depression expressed in plant populations.

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