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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.
461

Comparison of an intra-oral approach using a contra-angle hand piece with the transbuccal technique for mandibular angle fracture repair

Andre Stephanus de Waal. January 2010 (has links)
No description available.
462

An epidemiological analysis of traumatic cervical spine fractures at a referral spinal unit : a three-month study

Singh, Natasha January 2008 (has links)
Dissertation submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic Faculty: Health Sciences, Durban University of Technology, 2009 / Aim To determine the profile of traumatic cervical spine fractures with respect to the epidemiology, clinical presentation, types of fractures, conservative and surgical intervention, short-term post-intervention (i.e. post-conservative and post-surgical) complications and short-term post-surgical rehabilitation of patients presenting at the Spinal Unit of King George V Hospital over a 12-week period. Methods Patients who presented to the King George V Hospital Spinal Unit from surrounding hospitals with traumatic cervical spine fractures were evaluated by the medical staff. Data concerning the epidemiology, clinical presentation, types of fractures, conservative and surgical intervention, short-term post-intervention (i.e. post-conservative and postsurgical) complications and short-term post-surgical rehabilitation data were recorded by the researcher. A p-value of <0.05 was considered as statistically significant. Appropriate statistical tests were applied to the hypothesis-testing objectives. These involved the Pearson’s Chi Square Tests for categorical variables or Fisher’s Exact Tests as appropriate where sample sizes were small. Paired t-tests were done to compare preand- post-surgical Frankel grading and Norton Pressure Sore Assessment scores. Results The number of patients who presented to the Spinal Unit over a 12-week period was 20, of this number 17 were males, three were females and all were black. Eleven patients were treated surgically while nine patients were treated conservatively. The most frequent aetiology of cervical spine fractures was motor vehicle accidents (n = 10) followed by falls (n = 9). The most common co-existing medical conditions were smoking (n = 7), HIV (n = 5), alcohol abuse (n = 3) and obesity (n = 3). The most frequent locations of cervical spine fractures were C2 (n = 6), C1 (n = 4) and the posterior column of C6 (n = 3), while dislocations occurred primarily at the C5-C6 levels (n = 5) of the lower cervical spine. Odontoid fractures (n = 6), Jefferson’s fractures (n = 4) and unilateral facet dislocations (n = 6) were the most common fractures and dislocations v observed. Head injuries (n = 4) and lower limb fractures (n = 3) were the most common extra-spinal fractures. All subjects who sustained head injuries also had associated C1 or C2 fractures. Neurological complications most frequently involved the upper limb where loss of motor function (n = 8) and weakness (n = 4) were observed. The majority of the patients (n = 8) reported a Frankel Grading of E. There were no significant associations between types of fracture and gender with the exception of fracture/dislocation observed in two females. There was a statistically significant difference in the NPSA score (p = 0.004). Conservative care utilized included soft collar (n = 6), cones calipers (n = 6), physiotherapy (n = 4), Minerva jacket (n = 4) and SOMI (sterno-occipital mandibular immobilization) brace (n = 1) while surgical intervention included anterior decompression (n = 8), anterior fusion (n = 8), allograft strut (n = 8), discectomy (n = 8), anterior cervical plating (n = 8), anterior screw fixation (n = 2), a transoral approach (n = 1) and a corpectomy (n = 1). The short-term post-conservative care complications observed in this study were an occipital pressure sore (n = 1), severe discomfort (n = 1) as well as severe neck pain (n = 1), while the short-term post-surgical complications were severe neck pain (n = 2), oral thrush (n = 1), pneumonia (n = 1), odynophagia (n = 1) and hoarseness (n = 1). Of the 11 patients who underwent cervical spine surgery, ten were sent for physiotherapy and one for occupational therapy. No significant associations were seen between the type of cervical spine fracture and the age of the subject. There was a significant association between fracture/dislocation and the female gender (p = 0.016). There was significant negative association between odontoid fracture and: anterior decompression, anterior fusion, allograft strut, discectomy and anterior cervical plating (p = 0.006). Conclusion The results of this study reflect the presentation and management of cervical spine fractures at a referral spinal unit of a public hospital in KwaZulu Natal. The impact of HIV and other co-existing medical conditions were not determined due to the small sample size in this study. Further epidemiological studies are required to be conducted in the Spinal Units of all South African public hospitals in order to confirm or refute the observation of this study.
463

Geoterminio rezervuaro formavimas granito sluoksnyje Lietuvos geoterminės anomalijos zonoje / The formation of geothermal reservoir in the subsurface layer at the zone of Lithuanian geothermal anomaly

Karpavičius, Artūras 24 February 2011 (has links)
Vakarų Lietuvoje aptikus padidėjusį šilumos srautą, imta domėtis geoterminės energetikos perspektyvomis. Išmatavus geoterminės anomalijos zonos savybes pastebėta, kad šioje zonoje vyraujantis šilumos srautas yra dvigubai didesnis, nei likusioje Lietuvos teritorijoje ir yra dvigubai didesnis už vidutinį rytų Europos šilumos srautą, o aukštesnės nei 150 ºC temperatūros yra pasiekiamos kristalinio pamato uolienose. Pirminiai geoterminės anomalijos parametrai yra nustatomi geofizinių ir geocheminių metodų pagalba. Kiti parametrai – gręžinio eksploatacijos metu. Šių parametrų ţinojimas nulemia tolimesnę patobulintos geoterminės sistemos (Enhanced geothermal system, EGS) kūrimą. Aukšto slėgio geoterminis skystis spaudžiamas į porėtą uoliena, sąveikauja su ją sudarančiais mineralais ir deformuoja ją hidrosuplėšymo metu, taip praplėsdamas ir atverdamas naujus plyšius. Ši technologija yra vadinama stimuliuota sausų uolienų geoterminė sistema (Hot dry rock, HDR). Šių sistemų tikslas yra poţeminio šilumokaičio sukūrimas, pumpuojant aukšto slėgio vandens srautą į kristalinį pamatą. Taip formuojamas stimuliuotų plyšių koridorius, kuriuo cirkuliuoja gręžiniais pumpuojamas vanduo. / The geothermal energetic was found interesting for an anomalous heat flow at the west Lithuanian that is the most intense in a whole East European Platform. A higher temperature than 150 ºC is available in crystal basement at Lithuania at less than 5 km depth. To measure basic parameters of geothermal anomaly, geophysical and geochemical methods are applied. The other measurements are taken at the moment of hydrocirculation. Knowledge of these parameters will be used for the development and improvement of the enhanced geothermal system (EGS). High pressured water geothermal fluid is pumped into the rock in purpose to open old and create new cracks and fractures by exceeding rock compressive stress. For this reason there was created hot dry rock (HDR) system. The main goal of this system is to create a geothermal reservoir by pumping high pressure water flow into the rock. This way water circulates in enhanced geothermal system through the tunnel of fractures.
464

Acute confusional state (delirium) : clinical studies in hip-fracture and stroke patients

Gustafson, Yngve January 1991 (has links)
Acute confusional state (ACS) or delirium according to DSM-III-R holds a central position in the medicine of old age. ACS is a common and sometimes the only symptom of diseases and medical complications in the elderly patient. The aim of this study was to elucidate ACS in patients with femoral neck fractures and patients with acute stroke with regard to frequency, predictors, possible pathogenetic mechanisms, associated complications, assessment and documentary routines and the clinical outcome for the patients. An intervention program to prevent postoperative ACS based on our results was developed and evaluated. The main findings of the study were high frequencies of ACS in elderly patients with femoral neck fractures (61 %) and in patients with acute stroke (48 %). The main risk factors for ACS in patients with femoral neck fractures were old age, diseases and drug treatment interfering with cerebral cholinergic metabolism. There was no link between anaesthetic technique and ACS but the connection between peroperative hypotension, early postoperative hypoxia and ACS was close. In stroke patients the degree of extremity paresis and old age were independent ACS risk factors. ACS was commonly associated with post stroke complications such as myocardial infarction, pneumonia, urinary infection and urinary retention. In stroke patients there was a close connection between high hypothalamic-pituitary-adrenal axis (HPA-axis) activity and ACS. High HPA-axis activity and disturbances in the cerebral cholinergic system may be two important ACS mechanisms. A correct diagnosis is a prerequisite for proper treatment of ACS and its underlying causes. In the orthopaedic wards both physicians and nurses diagnosed and documented ACS poorly and therefore associated complications were insufficiently treated. The intervention program for postoperative ACS, aimed mainly at protecting the cerebral oxidative metabolism and thereby the cerebral cholinergic metabolism which is especially sensitive to hypoxia. Postoperative complications associated with ACS were also treated. The intervention resulted in reduced frequency, duration and severity of postoperative ACS and in shorter orthopedic ward stay for patients with femoral neck fractures.Key words: Acute confusional state, delirium, elderly / <p>S. 1-76: sammanfattning, s. 77-175: 6 uppsatser</p> / digitalisering@umu
465

DEVELOPMENT, VALIDATION, AND APPLICATION OF A NONINVASIVE SPINAL MOTION MEASUREMENT SYSTEM

Stinton, Shaun Kevin 01 January 2011 (has links)
Spontaneous vertebral fractures are a large and growing health care problem. Biomechanical factors, specifically, abnormal posture or gait‐related spinal motion may interact with age‐weakened bone to induce altered spinal biomechanics that in turn increase the likelihood of vertebral body fracture. This research takes steps towards the goal of reducing the number of vertebral fractures in two phases: 1) Validation of a noninvasive spinal motion measurement system in cadaver torsos and 2) Application of the measurement system in human subjects. The cadaver study compared vertebral motion at 4 levels (T7,T12,L3,L5) as measured by adhesive skin markers versus motion measured by bone pins implanted into the vertebrae. Cadaver torsos were tested in lateral‐bending, flexion and axialrotation. Mean differences in vertebral body angular motion between skin markers and bone pin markers were <0.5° around the anterior‐posterior and medial‐lateral axes and <0.9° around the superior‐inferior axis. This measurement method was able to accurately quantify vertebral body motion in cadaver torsos thus allowing for application to human subject testing. X‐rays and 3D motion capture were employed to quantify spinal posture and motion parameters during gait in 12 older and 12 younger normal, females. Vertebral motion around 3 axes was measured at 4 levels (T7,T10,T12,L2) using noninvasive retroreflective markers during treadmill gait at 3 speeds (0.5,0.7,0.9m/s). The average angular motion of all gait cycles at each speed was determined for each level. The triplanar ranges of motion and variability of motion were compared as a function of age. Older subjects had 31.7% larger frontal Cobb angles and up to 30.9% and 33.5% smaller ranges of spinal motion in the frontal and sagittal planes. Variability of motion in the sagittal plane was up to 42.9% less in older subjects. Decreased ranges of motion and variability of spinal motion observed in older subjects may imply that vertebral loading in these subjects may not be as uniformly distributed across the vertebrae as in younger subjects. Greater stresses may result from the abnormal motion, thus increasing fracture risk. Confirmation of this hypothesis requires a longitudinal study, but if verified, may lead to the development of inexpensive countermeasures to prevent fractures.
466

Bisphosphonates and Bone Microdamage

Caruthers, William A 01 January 2012 (has links)
Osteoporosis is a significant healthcare issue due to the increasing elderly population. Bisphosphonates are used to treat osteoporosis by reducing the rate of resorption, increasing bone mineral density (BMD) and thereby reducing fracture risk. Long-term bisphosphonate treatment, however, has been associated with low-energy fractures. Bone microdamage may provide a partial explanation for one of the mechanisms responsible for these fractures since it has been shown to reduce bone toughness, fracture resistance, and bone strength. The goal of this study was to quantify the changes in bone microdamage parameters with the duration of bisphosphonate treatment. This study selected, stained, and histomorphometrically analyzed 40 iliac crest bone biopsies from controls and female patients with osteoporosis treated with bisphosphonates for varying durations (up to 12 years). All subjects were matched for age and low turnover. The results showed that microcrack density and microcrack surface density were significantly greater in patients who took bisphosphonates for at least 5 years compared to those who took bisphosphonates for less than 5 years or not at all. These results reveal novel, clinically relevant information linking microdamage accumulation to long-term bisphosphonate treatment without influences from age or turnover.
467

Analysis of Seismic Data Acquired at the Forsmark Site for Storage of Spent Nuclear Fuel, Central Sweden

Sharifi Brojerdi, Fatemeh January 2015 (has links)
The Forsmark area, the main study area in this thesis, is located about 140 km north of Stockholm, central Sweden. It belongs to the Paleoproterozoic Svecokarelian orogen and contains several major ductile and brittle deformation zones including the Forsmark, Eckarfjärden and Singö zones. The bedrock between these zones, in general is less deformed and considered suitable for a nuclear waste repository. While several site investigations have already been carried out in the area, this thesis focuses primarily on (i) re-processing some of the existing reflection seismic lines to improve imaging of deeper structures, (ii) acquiring and processing high-resolution reflection and refraction data for better characterization of the near surface geology for the planning of a new access ramp, (iii) studying possible seismic anisotropy from active sources recorded onto sparse three-component receivers and multi-offset-azimuth vertical seismic profiling data (VSP). Reflection seismic surveys are an important component of these investigations. The re-processing helped in improving the deeper parts (1-5 km) of the seismic images and allowing three major deeper reflections to be better characterized, one of which is sub-horizontal while the other two are dipping moderately. These reflections were attributed to originate from either dolerite sills or brittle fault systems. First break traveltime tomography allowed delineating an undulating bedrock-surface topography, which is typical in the Forsmark area. Shallow reflections imaged in 3D, thanks to the acquisition design were compared with existing borehole data and explained by fractured or weak zones in the bedrock. The analysis of seismic anisotropy indicates the presence of shear-wave splitting due to transverse isotropy with a vertical symmetry axis in the uppermost hundreds of meters of crust. Open fractures and joints were interpreted to be responsible for the large delays observed between the transverse and radial components of the shear-wave arrivals, both on surface and VSP data.
468

Epidemiology of joint injuries in thoroughbred racehorses in training

Reed, Suzanne Rene January 2011 (has links)
No description available.
469

Thermo-Hydro-Mechanical Behavior of Conductive Fractures using a Hybrid Finite Difference – Displacement Discontinuity Method

Jalali, Mohammadreza January 2013 (has links)
Large amounts of hydrocarbon reserves are trapped in fractured reservoirs where fluid flux is far more rapid along fractures than through the porous matrix, even though the volume of the pore space may be a hundred times greater than the volume of the fractures. These are considered extremely challenging in terms of accurate recovery prediction because of their complexity and heterogeneity. Conventional reservoir simulators are generally not suited to naturally fractured reservoirs’ production history simulation, especially when production processes are associated with large pressure and temperature changes that lead to large redistribution of effective stresses, causing natural fracture aperture alterations. In this case, all the effective processes, i.e. hydraulic, thermal and geomechanical, should be considered simultaneously to explain and evaluate the behavior of stress-sensitive reservoirs over the production period. This is called thermo-hydro-mechanical (THM) coupling. In this study, a fully coupled thermo-hydro-mechanical approach is developed to simulate the physical behavior of fractures in a plane strain thermo-poroelastic medium. A hybrid numerical method, which implements both the finite difference method (FDM) and the displacement discontinuity method (DDM), is established to study the pressure, temperature, deformation and stress variations of fractures and surrounding rocks during production processes. This method is straightforward and can be implemented in conventional reservoir simulators to update fracture conductivity as it uses the same grid block as the reservoir grids and requires only discretization of fractures. The hybrid model is then verified with couple of analytical solutions for the fracture aperture variation under different conditions. This model is implemented for some examples to present the behavior of fracture network as well as its surrounding rock under thermal injection and production. The results of this work clearly show the importance of rate, aspect ratio (i.e. geometry) and the coupling effects among fracture flow rate and aperture changes arising from coupled stress, pressure and temperature changes. The outcomes of this approach can be used to study the behavior of hydraulic injection for induced fracturing and promoting of shearing such as hydraulic fracturing of shale gas or shale oil reservoirs as well as massive waste disposal in the porous carbonate rocks. Furthermore, implementation of this technique should be able to lead to a better understanding of induced seismicity in injection projects of all kinds, whether it is for waste water disposal, or for the extraction of geothermal energy.
470

Ambulanssjuksköterskors möjlligheter att bedriva evidensbaserad vård vid prehospital smärtbehandling av patienter med höftfraktur / The Ambulance nurses possibilities to practice prehospital evidence-based care during pain relief of hip fractures

Larsson, Margareta, Pettersson, Jonas, Reckebo, Sten January 2015 (has links)
Väntetiden för patienter som ådragit sig höftfraktur till operation är ofta lång och kan uppgå till över ett dygn. I första delen av vårdkedjan är det ambulanssjuksköterskan som möter patienter som ådragit sig höftfraktur och omhändertagandet där smärtbehandling ingår genomförs med stöd av upprättade vårdriktlinjer. Ambulanssjuksköterskan har ett ansvar enligt svensk lag att den prehospitala akutsjukvården som genomförs ska vara evidensbaserad. Syftet med denna studie var att undersöka specialistutbildade ambulanssjuksköterskors uppfattningar om möjligheten att bedriva evidensbaserad vård vid prehospital smärtbehandling av patienter med höftfraktur. Detta är en kvalitativ studie med beskrivande design. Resultatet visade att den specialistutbildade ambulanssjuksköterskan uppfattade generellt att vårdriktlinjerna var tydliga och lätta att förhålla sig till. De uppfattade att smärtbehandling var väl fungerande och evidensbaserad. Vårdriktlinjerna var tydliga och lätta att förhålla sig till och informanterna uppfattade att smärtbehandlingen var väl fungerande och evidensbaserad. / The waiting time for patients that sustain hip fractures is often long and can be more than twenty-four hours. The Ambulance nurse provides the first care for those whom sustain a hip fracture.  These patients receive pain management care from the ambulance nurse as recommended by given guidelines.  The ambulance nurse has a responsibility by Swedish law to administer care in an evidence based care, prehospital in the emergency care. The intention of this study was to investigate the specialist educated ambulance nurses current opinions of the possibility to give evidence based care, during prehospital pain management to patients who have a hip fracture. This is a qualitative study with descriptive design. The outcome of this study shows that the specialist educated ambulance nurses believe that the guidelines are clear and easy to follow in general.  Their opinion was that the pain management was functional and evidence based. The guidelines were clear and easy to relate to and the informants experienced the pain management as evidence based.

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