• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 38
  • 19
  • 14
  • 9
  • 9
  • 3
  • 2
  • 1
  • Tagged with
  • 119
  • 19
  • 11
  • 11
  • 11
  • 11
  • 11
  • 10
  • 10
  • 9
  • 8
  • 8
  • 8
  • 8
  • 8
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Faktorer som påverkar bemanning på RiB-stationer : En studie av vilka faktorer som påverkar beredskapsgruppers storlek samt en undersökning av Jämtlands RiB-bemanning

Edström, Jennie January 2024 (has links)
Enligt Lag (2003:778) om skydd mot olyckor ska skyddet mot olyckor i Sverige vara tillfredsställande och likvärdigt med hänsyn till lokala förhållanden. Kommuner är skyldiga att i ett handlingsprogram för räddningstjänst ange bland annat de risker för olyckor vilka finns i kommunen, förmågan att genomföra räddningsinsatser samt vilka resurser som finns för att upprätthålla den förmågan. Detta kräver en bemanning som är anpassad till riskbilden. I dagsläget upplevs det finnas brister och problem kopplade till Jämtlands räddningstjänstförbunds (JRF:s) placering och omfattning av personal på dess deltidsstationer, då underlag saknas till varför bemanningen är fördelad som den är. Inledningsvis genomfördes en litteraturstudie och en intervjustudie med syftet att undersöka vilka ingångsparametrar som påverkar beredskapsgruppers storlek och att ta fram en process som kan nyttjas som beslutsunderlag kring bemanning på stationerna i förbundet med räddningstjänstpersonal i beredskap (RiB). Litteraturstudien utfördes för att inhämta och kartlägga information om räddningstjänsten Jämtland, relevanta begrepp och regelverk samt för att få en grundläggande förståelse för vilka parametrar som kan påverka bemanningen. Intervjustudien genomfördes med personal inom JRF, sex olika räddningstjänster i Sverige, myndigheten för samhällsskydd och beredskap (MSB) samt Sveriges kommuner och regioner (SKR). Syftet med intervjuerna var att från olika organisationers perspektiv undersöka vilka faktorer som bör vägas in i beslut gällande vilken bemanning en station bör ha. De faktorer vilka identifierades som viktiga att beakta var riskbild, förstärkande styrkor, politiska ambitioner, regelverk och riktlinjer, nyckeluppgifter, effektivitet, arbetsmiljö, framtida exploateringar, likriktning, likvärdighet samt gränsöverskridande påverkan. De kan sammanfattas i fyra steg; nyckeluppgifter, styrkeuppbyggnad, likvärdighet och övriga förutsättningar. Ett förslag på metodik att använda vid analysering av bemanning på RiB-stationer gavs därefter. En undersökning av bemanning på JRF:s samt Åres stationer gjordes förenklat med hjälp av den framtagna metodiken för att besvara frågan på om JRF har en bemanning anpassad efter dess riskbild, vilket mynnade ut i förslag på att förändra bemanningen på tio av de 34 RiB-stationerna.
12

Age estimation on two Mediterranean samples using rib histomorphometry

Gómez García-Donas, Julia January 2018 (has links)
Estimation of age is a crucial step for the identification of unknown individuals. Age is commonly assessed through macroscopic analytical methods based on the gross-examination of age degenerative changes in the skeleton. The choice of the methods relies on the taphonomic condition of the human remains and/or the skeletal element that is available. In cases of very fragmented bones, microscopic techniques remain one of the few approaches to estimate age. Thus, many histological age estimation methods have been developed for different bones and on different samples in the last forty years. Numerous intrinsic and extrinsic factors influence bone remodelling rates and have shown to affect the accuracy of histological aging methods. The present study investigates rib thin-sections from two Mediterranean samples, aiming to explore the applicability and reliability of histological methods in estimating age within these samples. Standard ribs were obtained from males and females (N = 88, Mean age = 60, SD = 17.90) from two samples, Cretans (Greece) and Greek- Cypriots (Republic of Cyprus). The costal elements were processed histologically according to standard protocols and thirteen raw and composite histomorphometric parameters (frequency number of intact and fragmentary osteons, total osteons, osteon population densities - including OPD(I) and OPD(F) - cortical area, total area, endosteal area, relative cortical area, osteon area, osteon perimeter and osteon circularity) were assessed. Intra- and inter-observer errors were examined. Due to the fragmented nature of the costal elements, sampling error was calculated as a means to explore whether the histological variables vary among six different topographical locations along the rib length. A validation study was carried out by applying four existing histological age prediction equations on the entire dataset and on the sub-datasets (sex and samples separately) in order to verify whether population-specific formulae are required for the Mediterranean samples. The relationship between the histological variables and age, as well as sex and samples, was determined through several statistical tests. Lastly, simple and multiple regression analyses were performed testing all possible combinations of variables. The best models ii were finally selected according to prediction power and goodness of fit indicators. The results from intra- and inter-observer errors indicated that most of the histological parameters achieved high levels of repeatability. The preliminary outcome from the sampling error pilot study suggested low variability among the six thin-sections from each rib. According to the validation study, three of the four age prediction equations resulted in high underestimation of age, indicating that population-specific formulae are needed to provide more accurate age estimates. Most of the histological variables showed a statistically significant correlation with age with some differences observed by sex and by sample. Forty-one models were generated concluding that osteon densities along with rib and osteon measurements formulae produced the most accurate results. The best model generated from the entire dataset included OPD and osteon circularity with a standard error of the estimate of 10.45 years. When sex and samples were separated, the best model selected included OPD and osteon perimeter producing a standard error of the estimate of 8 years for Cypriots. This research demonstrates that quantitative bone histology is a feasible method to estimate age on the Mediterranean samples obtaining errors rates that are in accordance with macroscopic ageing techniques. Inter-population variation in remodeling rates is suggested; however, the inclusion of other bones presenting different remodelling dynamics (such as femora) is recommended to further explore this hypothesis. This study contributes to the creation of population-specific standards for Cretans and Cypriots.
13

Transcostal focused ultrasound surgery : treatment through the ribcage

Gao, Jing January 2012 (has links)
Two issues hindering the clinical application of image-guided transcostal focused ultrasound surgery (FUS) are the organ motion caused by cardiac and respiratory movements and the presence of the ribcage. Intervening ribs absorb and reflect the majority of ultrasound energy excited by an acoustic source, resulting in insufficient energy delivered to the target organs of the liver, kidney, and pancreas. Localized hot spots also exist at the interfaces between the ribs and soft tissue and in highly absorptive regions such as the skin. The aim of this study is to assess the effects of transmitted beam distortion and frequency-dependent rib heating during trans-costal FUS, and to propose potential solutions to reduce the side effects of rib heating and increase ultrasound efficacy. Direct measurements of the transmitted beam propagation were performed on a porcine rib cage phantom, an epoxy rib cage phantom and an acoustic absorber rib cage phantom, in order of their similarities to the human rib cage. Finite element analysis was used to investigate the rib cage geometry, the position of the target tissue relative to the rib cage, and the geometry and operating frequency of the transducer. Of particular importance, frequency-dependent heating at the target and the intervening ribs were estimated along with experimental verification. The ratio of ultrasonic power density at the target and the ribs, the time-varying spatial distribution of temperature, and the ablated focus of each sonication are regarded as key indicators to determine the optimal frequency. Following that, geometric rib-sparing was evaluated by investigating the operation of 2D matrix arrays to optimize focused beam shape and intensity at target. Trans-costal FUS is most useful in treating tumours that are small and near the surface of the abdominal organs, such as the liver, kidney and pancreas. However, for targets deep inside these organs, severe attenuation of acoustic energy occurs, suggesting that pure ultrasound thermal ablation with different heating patterns will have limited effects in improving the treatment efficacy. Results also demonstrate that the optimal ultrasound frequency is around 0.8 MHz for the configurations considered, but that it may shift to higher frequencies with changes in the axial and lateral positions of the tumours. In this work, I aimed to reduce the side effects of rib heating and increase the ultrasound efficacy at the focal point in trans-costal treatment. However, potential advanced techniques need to be explored for further enhanced localized heating in trans-costal FUS.
14

New developments on preparation of cooled and bunched radioactive ion beams at ISOL-Facilities: the ISCOOL project and the rotating wall cooling

Podadera Aliseda, Ivan 07 July 2006 (has links)
Last years have become very productive for the research, construction and development of new facilities devoted to the production of beams with exotic radioisotopes (Radioactive Ion Beams, RIB). These beams are later used for experiments in fields like nuclear physics, atomic physics, astrophysics or medicine, among others. Within this kind of facilities, the ISOL facilities stand out. They are based on the on-line separation of radioactive isotopes produced in nuclear reactions between a target and a high-energy proton beam. The ISOL method was the pioneer for these facilities and it has kept up to now the leadership of RIB facilities. The main reason is ISOLDE, an ISOL facility located at CERN, the largest accelerator complex in the world, where this doctoral thesis has been carried out.The first innovation which is described is the design of an ion trap for the cooling and bunching of RIB's for ISOLDE, the so-called ISCOOL (ISOLDE COOLer). It is an Radio Frequency Quadrupole ion Cooler and Buncher (RFQCB), device based on the Paul traps. In these traps, the ions are confined in the three dimensions by electric fields. The ions are confined on the transverse plane with the pseudopotential well created by the Radio Frequency Quadrupole (RFQ) and focused on the longitudinal axis. At the same time, a gas (normally helium) fills the chamber with a pressure between 10-3 and 10-2 mbar. The collisions between the atoms or molecules of the gas and the ions. In addition, to drive the ions to the extraction of the RFQCB, an axial electric field is created by segmented electrodes. Different voltages are applied to these electrodes in order to choose the shape of the field. The shape can be chosen to create a potential well close to the extraction from the RFQCB in which the ions are accumulated and extracted as bunches, by the fast-switch of the voltages applied to the axial electrodes.The new ISCOOL will be installed as a permanent device of the ISOLDE beam lines.
15

Numerical analysis of laminar convective heat transfer of ribs in the parallel-plate channel

Yang, Min-hsiung 08 July 2010 (has links)
Numerical study of laminar convective cooling of ribs in a parallel plate channel is investigated. Single rib mounted on one channel wall in forced, mixed and free convection is analyzed. Furthermore, the series ribs array with in-line and staggered mounted on channel walls are considered. Through the use of a stream function vorticity transformation, solution of the transformed governing equations for the system is obtained using the control volume method with non-uniform grid. The effects of the Reynolds number, thermal conductivity ratio of rib to fluid and rib¡¦s profile area on heat transfer rate of single rib and rib array are presented. In addition, the effects of the length from inlet to the first rib and the space between ribs for rib array are carried out. A correlation for single and rib array in forced convection is presented to estimate the optimum aspect ratio of rib with various Reynolds number, thermal conductivity ratio of rib to fluid, rib¡¦s profile area. Furthermore, the results of different Gr/Re2 and various channel inclination angle in mixed convection are also examined numerically. The results indicate that both in forced and mixed convection, the optimum aspect ratio of a rib corresponding to the rib with maximum heat transfer rate increases with increasing Re but decreases with K for a fixed rib profile area. In forced convection the optimum aspect ratio of rib array increases with rib¡¦s space but decreases with the length from inlet to the first rib of channel. Then, numerical correlations to predict the optimum aspect ratio of single rib and rib array are developed for fixed rib¡¦s area with various Re, K and rib number. In mixed convection, the optimum aspect ratios of single rib and staggered rib array increase with not only the inclination angle but also Gr/Re2.
16

The Beef Nutrient Database Improvement Project: Retail Cuts From the Rib and Plate

May, Laura 2010 December 1900 (has links)
The purpose of this study was to collect and analyze retail cuts from the beef rib and plate that had been identified as needing nutrient composition updates in the United States Department of Agriculture’s (USDA) National Nutrient Database for Standard Reference (SR). Twenty beef carcasses were selected from three different regions of the United States, and the rib and plate were collected for shipment via refrigerated truck to the Rosenthal Meat Science and Technology Center. Each rib and plate was fabricated 14 to 21 d postmortem into the appropriate retail cuts to be used for this study. The cuts were dissected, either raw or cooked (braised, grilled, roasted), into four separable components: separable lean, seam fat, external fat, and refuse. Bone and heavy connective tissue were considered refuse. Percent total chemical fat, moisture, protein, and ash analyses were conducted on the separable lean component obtained from dissection. Cooking yields were evaluated for each of the three cooking methods utilized in this study. Grilled cuts had the highest numerical yield followed by roasted and braised cuts. Dissection data showed single muscle cuts had a higher percentage of separable lean than retail cuts composed of multiple muscles. Boneless and lip-off retail cuts contained a higher percentage of separable lean when compared to their bone-in and lip-on counterparts. Finally, proximate analysis data showed that as retail cuts increased in the percentage of total chemical fat, the percentage of moisture decreased. When percentage of total chemical fat was stratified by USDA quality grade, most cuts showed differences between USDA Choice and Select quality grades. This study was a collaborative project; therefore, the results and discussion of this thesis are only based on findings from Texas A and M University's data. The final project results will be published in the USDA’s National Nutrient Database SR.
17

Proposição, validação e aplicação de um novo metodo para analise cinematica tridimensional da movimentação da caixa toracica durante a respiração / Proposition, validation and application of a novel method to the 3D kinematical analysis of the rib cage motion during breathing

Sarro, Karine Jacon, 1977- 30 November 2007 (has links)
Orientador: Ricardo Machado Leite de Barros / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Fisica / Made available in DSpace on 2018-08-09T17:18:56Z (GMT). No. of bitstreams: 1 Sarro_KarineJacon_D.pdf: 1134388 bytes, checksum: b567c37751844e9b74d352b031f141d7 (MD5) Previous issue date: 2007 / Resumo: O presente trabalho teve como objetivo propor e validar um novo método para análise cinemática tridimensional da movimentação da caixa torácica durante a respiração e mostrar uma aplicação do mesmo. A análise cinemática foi utilizada para descrever a movimentação tridimensional das costelas durante a respiração. As coordenadas 3D de marcadores posicionados sobre as costelas e vértebras foram utilizadas para calcular as distâncias transversais e ântero-posteriores da caixa torácica e a orientação das costelas em função do tempo. O método identificou um sinal coerente com o ciclo respiratório para todas as distâncias calculadas e também para os ângulos das costelas ao redor de um eixo quasi-transversal representando os movimentos de elevação e abaixamento das costelas. Também foi capaz de medir a maior variação das distâncias ântero-posteriores e transversais da caixa torácica durante respirações em capacidade vital quando comparadas a respirações em volume corrente. Foram realizados testes para avaliar variáveis relacionadas aos erros de medição do sistema de análise cinemática utilizado. Imagens de ressonância magnética do tronco foram utilizadas para calcular a movimentação relativa entre os marcadores de superfície e as costelas (deslizamento de pele). Os resultados revelaram um erro sistemático abaixo de 1 mm e um desvio padrão experimental de 2,5 mm, o que gerou erros máximos de 2º na medição da variação angular das costelas. A movimentação relativa média entre os marcadores, assumida como a distância entre o marcador e a costela em capacidade pulmonar total menos a distância entre o marcador e a costela em capacidade residual funcional, foi igual a 3,9 mm, valor menor que os relatados na literatura para os membros inferiores ou coluna vertebral. Esses resultados validam o método, mostrando a viabilidade em se usar a análise cinemática para avaliar movimentações das costelas acima de 2º. Uma vez validado, o método foi aplicado a um grupo de sujeitos saudáveis e distinguiu alguns sujeitos com movimentação paradoxal das costelas. Aplicado a um grupo de nadadores, foi capaz de evidenciar alterações nos movimentos respiratórios desse grupo, identificando maior variação angular das costelas e maior correlação entre as curvas dos ângulos das costelas (p<0,05) quando comparado ao grupo controle. Os nadadores também apresentaram maior correlação entre a variação angular das costelas e os volumes parciais do tronco, reforçando o potencial da metodologia em identificar alterações nos padrões respiratórios. Concluindo, este estudo validou o uso da análise cinemática 3-D para avaliar a movimentação das costelas e a coordenação entre elas durante a respiração bem como evidenciou seu potencial na identificação de diferentes comportamentos da movimentação das costelas, mostrando que a prática de natação induziu um padrão otimizado de movimentação da caixa torácica / Abstract: The present work aimed to propose and validate a novel method to the 3D kinematical analysis of the rib cage motion during breathing and to show an example of application. The kinematical analysis was used to describe the 3D motion of the ribs during breathing. The 3D coordinates of surface markers positioned on the ribs, sternum and vertebrae were used to calculate the transversal and anterior-posterior distances of the rib cage and the orientation of the ribs in function of time. The method identified a signal coherent with the breathing cycle for all the distances measured and for the angles of the ribs around the quasi-transversal axis representing the upward and downward movements of the ribs. The method was also able to identify the higher variation of the transversal and anterior-posterior distances of the rib cage during breathing at vital capacity when compared with breathing at tidal volume. Some tests were performed to evaluate variables related to the measurement errors of the system. Magnetic resonance images of the trunk were used to calculate the relative motion between the surface markers and the ribs (soft tissue artifact). The results revealed less than 1 mm of systematic error and a experimental standard deviation of 2.5 mm, which generate maximal errors of 2º on the angular variation of the ribs. The soft tissue artifact was assumed as the distance between the marker and the rib at total lung capacity minus the distance between the marker and the rib at functional residual capacity, and the absolute mean value found was 3.9 mm. This value is smaller than that one found in the kinematics of other segments. The method was applied in a group of swimmers and a control group of non-athletes and was able to distinguish subjects with a paradoxal movement and showed that swimmers presented greater angular variation for all ribs, and greater correlation between the curves of the rib angles (p<0.05). The swimmers also presented higher correlation between the angular variation of the ribs and the variation of the separate volumes of the trunk. In conclusion, this study has validated the use of 3-D kinematic analysis to evaluate the movement of the ribs and their coordination during breathing as well as has shown its potential to identify differences in the behavior of the ribs motion, showing that swimming training induced an optimized pattern of motion of the rib cage / Doutorado / Biodinamica do Movimento Humano / Doutor em Educação Física
18

Sensitivity and specificity of thoracic radiography relative to computed tomography in dogs affected by blunt trauma caused by a motor vehicle accident

Dancer, Sumari Constance January 2019 (has links)
Thoracic injuries caused by blunt trauma are commonly encountered emergencies in veterinary medicine. However, no literature exists comparing radiography to computed tomography (CT) in blunt thoracic trauma caused by motor vehicle accidents in canine patients. The aim of this prospective case series was to estimate the sensitivity (Se) and specificity (Sp) of thoracic radiography relative to CT for detecting lung contusions, pneumothorax, pleural effusion and rib fractures. The study further aimed to establish a severity scoring system for radiography and CT and to compare the findings between the two modalities. The hypothesis was that radiography would be less sensitive than CT at detecting these injuries and that radiography would underestimate the severity of lung contusions compared to CT. Fifty-nine patients met the inclusion criteria. Radiography underestimated the presence of lung contusions (Se = 69%, 95% Confidence interval (CI)) and overestimated the severity of the contusions relative to CT. There was also high interobserver variability in evaluating lung contusion severity (coefficient of variation = 91%). Both the three-view thoracic and horizontal beam radiography had poor sensitivities for the detection of pneumothorax (Se = 19% and 63% respectively) and pleural effusions (Se = 43% and 71% respectively). Similarly, the sensitivity (56%) of three-view thoracic radiographs for the detection of rib fractures was poor relative to CT. To conclude, three-view thoracic radiography had low sensitivity for pathology related to blunt thoracic trauma caused by motor vehicle accidents and CT could be considered as an additional diagnostic imaging modality in these patients. / Dissertation (MMedVet (Diagnostic Imaging))--University of Pretoria, 2019. / Companion Animal Clinical Studies / MMedVet (Diagnostic Imaging) / Unrestricted
19

Age estimation from features of the first rib

Dooley, Ellen V. 17 June 2020 (has links)
Several techniques for estimating adult age-at-death are used in biological and forensic anthropology, including morphological changes of the ribs. However, due to human variation and taphonomic damage, it remains difficult to produce accurate and meaningful age-at-death estimations based on skeletal remains. This research further explores morphological changes to the first rib, which is easily identifiable and relatively robust, including the costal face and tubercle facet identified by Kunos’ (1999) and modified by DiGangi et al. (2009). A total of 400 European American individuals (f=200; m=200) from the William M. Bass Donated Skeletal Collection at the University of Tennessee, Knoxville, were observed using modified descriptions for Kunos’ (1999) five traits of the costal face and tubercle facet, on an ordinal scale of 1-8. Additionally, bone quality was assessed on an ordinal scale of 1-3 and was incorporated as a variable in order to improve estimations. Exploratory statistical analysis demonstrates that all eleven traits correlate with age at a statistically significant level, with bone quality being the most significant feature for both sexes. Female and male differences were found, and cross-validated ordinal logistic regression equations are presented for each. The resulting AIC table estimates 100% of the male and female sample correctly, though the produced ranges are too large to be forensically relevant. The results of this research underscore the importance of developing age estimation methods on skeletal regions that are under researched and for those that are more resistant to taphonomic damage.
20

Intravenous Lidocaine for Rib Fractures: Effect on Pain Control and Outcome

King, Sarah, Smith, Lou, Harper, Christopher, Beam, Zachary, Heidel, Eric, Carico, Genevieve, Wahler, Kelsey, Daley, Brian 01 January 2021 (has links)
Background: Multimodal analgesia in rib fractures (RFs) is designed to maximize pain control while minimizing narcotics. Prior research with intravenous lidocaine (IVL) efficacy produced conflicting results. We hypothesized IVL infusion reduces opioid utilization and pain scores. Methods: A retrospective review of RF patients at an ACS-verified Level I trauma center from April 2018 to 2/2020 was conducted. Patients (pts) stratified as receiving IVL vs no IVL. Initial lidocaine dose: 1 mg/kg/hr with a maximum of 3 mg/kg/hr. Duration of infusion: 48 h. Pain quantified by the Stanford Pain Score system (PS). Bivariate and multivariate analyses of variables were performed on SPSS, version 21 (IBM Corp). Results: 414 pts met inclusion criteria: 254 males and 160 females. The average age for the non-IVL = 67.4 ± 15.2 years vs IVL = 58.3 ± 17.1 years (P <.001). There were no statistically significant differences between groups for ISS, PS for initial 48 h, and ICU length of stay (LOS). There was a difference in morphine equivalents per hour: non-IVL = 1.25 vs IVL = 1.72 (P =.004) and LOS non-IVL = 10.2+/−7.6 vs IVL = 7.82+/−4.94. By analyzing IVL pts in a crossover comparison before and after IVL, there was reduction in opiates: 3.01 vs 1.72 (P <.001) and PS: 7.0 vs 4.9 (P <.001). Stanford Pain Score system reduction in the IVL = 48.3 ± 23.9%, but less effective in narcotic dependency (27 ± 22.9%, P =.035); IVL pts had hospital cost reduction: $82,927 vs $118,202 (P <.01). Discussion: In a crossover analysis, IVL is effective for reduction of PS and opiate use and reduces hospital LOS and costs. Patient age may confound interpretation of results. Our data support IVL use in multimodal pain regimens. Future prospective study is warranted.

Page generated in 0.0425 seconds