• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 42
  • 42
  • 16
  • 13
  • 5
  • 5
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 152
  • 38
  • 29
  • 23
  • 22
  • 22
  • 20
  • 19
  • 19
  • 18
  • 17
  • 14
  • 13
  • 12
  • 12
  • 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.
91

Validation of Markerless Motion Capture for the Assessment of Soldier Movement Patterns Under Varying Body-Borne Loads

Coll, Isabel 01 May 2023 (has links)
Modern soldiers are burdened by an increase in body-borne load due to technological advancements related to their armour and equipment. Despite the potential increase in safety from carrying more protective equipment, a heavier load on the soldier might decrease field performance both cognitively and physically. Additionally, an increasing load on military personnel concurrently increases their risk of musculoskeletal injuries. Therefore, there is a necessity for research on the soldier's biomechanical outcomes under different loading conditions. When it comes to biomechanics research, marker-based technology is widely accepted as the gold standard in terms of motion capture. However, recent advancements in markerless motion capture could allow the quick collection of data in various training environments, while avoiding marker errors. In this research project, the Theia3D markerless motion capture system was compared to the marker-based gold standard for application on participants across varying body-borne load conditions. The aim was to estimate lower body joint kinematics, gastrocnemius lateralis and medialis muscle activation patterns, and lower body joint reaction forces from the two motion capture systems. Data were collected on 16 participants for three repetitions of both walking and running under four body-borne load conditions by both motion capture systems simultaneously. Electromyography (EMG) data of lower limb muscles were collected on the right leg and force plates measured ground reaction forces. A complete musculoskeletal analysis was completed in OpenSim using the Rajagopal full-body model and standard workflow: model scaling, inverse kinematics, residual reduction, static optimization, and joint reaction analysis. Estimations of joint kinematics and joint reaction forces were compared between the two systems using Pearson's correlation coefficient, root-mean-square errors, and Bland-Altman limits of agreement. Very strong correlations (r = 0.960 ± 0.038) and acceptable differences (RMSE = 7.8° ± 2.6°) were observed between the kinematics of the marker-based and markerless systems, with some angle biases due to joint centre differences between systems causing an offset. Because the marker-based motion capture system lost line of sight with markers more frequently in the heavier body-borne load conditions, differences generally increased with heavier body-borne loads. Timing of muscle activations of the gastrocnemius lateralis and medialis as estimated from both systems agreed with the ones measured by the EMG sensors. Joint reaction force results also showed a very strong correlation between the systems but the markerless model seemed to overestimate joint reaction forces when compared to results from the marker-based model. Overall, this research highlighted the potential of markerless motion capture to track participants across all body-borne load conditions. However, more work is necessary on the determination of angle bias between the two systems to improve the use of markerless data with OpenSim models.
92

The Effects of a Novel Exercise Training Suit on Cardiorespiratory Fitness, Body Composition and Leg Strength

Curry, Trevor M, Davis, Steven C, Nazmi, Aydin, Clegg, Don 01 June 2015 (has links) (PDF)
ABSTRACT The Effects of a Novel Exercise Training Suit on Cardiorespiratory Fitness, Body Composition and Leg Strength Trevor Michael Curry The physiological responses to physical activity or exercise using external load carriage systems (LCS) in the form of weighted personal protective equipment, backpacks, or vests have biomechanical and human performance implications. It remains unclear whether a new unique LCS in the form of a weighted (5.45 kg) full-bodied exercise suit can induce greater improvements in performance and body composition. Twenty-one healthy males (20±3 years; 24.9±3.6 body mass index (BMI); 25.1±6.4% total percentage body fat ( % fat); 120.1±17.3 kg lean mass; 146.2±35.4 kg leg press 1-repetition max; 1.25±0.14 g·cm-2 bone mineral density; 49.5±8.53 mLO2·kg-1·min-1 maximal oxygen consumption (VO2max)) were matched for VO2max and physical characteristics before being randomly allocated into an aerobic exercise intervention with or without the exercise suit using a treadmill at the Cal Poly Recreation Center. Participants jogged at 60%-70% of their maximum heart rate for 30 min three times a week on nonconsecutive days for six weeks. Weight was recorded before and after each session while heart rates, blood pressures, and tympanic membrane temperatures were recorded incrementally during each session. Thereafter, VO2max and the same physical characteristics were measured and used to analyze the changes before and after the 6-week program. The results indicate that there was no difference for the change in any of the variables measured during and between the exercise intervention. Future studies examining the effect of the exercise suit on these variables should strongly consider larger sample sizes and other subpopulations to gain the statistical power to measure the effects of the exercise suit.
93

Variability and local dynamic stability during gait: an investigation of military-relevant load carriage and hip pathology

Loverro, Kari Lyn 06 July 2018 (has links)
The primary goal of human locomotion is to translate the body from point A to point B, but humans must have the variability and stability to adapt and recover from constraints they may encounter. The overarching aim of this dissertation was to investigate how constraints arising from external factors (i.e., military load carriage and speed) and internal factors (i.e., hip pain) affect kinematic variability and local dynamic stability of gait. In study 1, I focus on using traditional biomechanical measures to investigate if females and males use different gait mechanics when carrying military-relevant loads, as females and males are known to use different mechanics when walking with no load. In this study, I found that females and males do use different gait mechanics when walking with military-relevant loads. Females make kinematic adaptations at the ankle and knee while males make kinematic adaptations at the hip. The differences in adaptations between females and males may be related to females’ greater risk of injury when carrying load. In study 2, I used the same cohort to investigate how military-relevant loads affect the kinematic variability and local dynamic stability of gait. I found that kinematic variability and local dynamic stability were similarly affected by load. Participants had greater kinematic variability and decreased local dynamic stability when carrying loads, which may indicate an increased risk of falling while carrying load. I also found that local dynamic stability increased with increased walking speed at all loads in the mediolateral and anteroposterior directions. However, decreased stability was detected in the vertical direction, which may require increased energy expenditure. The results of this study indicate that walking faster with increased loads may be more stable, but less energy efficient. In study 3, I investigated the how kinematic variability and local dynamic stability were affected in individuals with hip pain and a history of developmental dysplasia. I found that kinematic variability and local dynamic stability were not similarly affected in these individuals. I found that kinematic variability was greater in individuals with hip pain compared to healthy controls, but there was no difference in local dynamic stability between groups. The overall finding of this dissertation is that the relationship between kinematic variability and local dynamic stability may be dependent on the factor investigated. / 2020-07-06T00:00:00Z
94

Investigation into Biomechanical Response and Health Consequences of Military Rucksack Design for Female Soldiers

Grawe, Sarah Koop 16 September 2014 (has links)
No description available.
95

Chronic Carriage of <i>Salmonella</i>: Biofilms and Gallstones

Crawford, Robert William 02 September 2009 (has links)
No description available.
96

Predicting the Joint Stiffness of Wooden Pallets Assembled with Lag Screws and Carriage Bolts

Keller, Joseph David 20 April 2023 (has links)
Master of Science / Pallets are used all over the world in the field of distribution. The strength values associated with a pallet have been thoroughly investigated by many different researchers; however, the stiffness values associated with pallet joints have not. The goal of this work was to investigate the stiffnesses associated with pallets joints made with lag screws and carriage bolts. It is important to understand that different materials, fastening methods, and design considerations can have a huge impact on the stiffness of the joint. This paper will discuss the various tests that were used to measure the actual stiffness of pallet joints and the results of those tests. Afterwards, the researchers detail their attempt to predict the stiffness using an equation created from the actual test data. Finally, by understanding the effects of these various factors, better pallet designs can be created that are both safer and stronger using the investigated alternative fasteners.
97

Improving Cable Logging Operations for New Zealand’s Steep Terrain Forest Plantations

Harrill, Hunter January 2014 (has links)
Cable logging will become more important as harvesting shifts to greater annual proportions on steep terrain in New Zealand. The costs of cable logging are considerably higher than that of conventional ground-based methods. Improving cost-effectiveness has been identified as key to ensuring the forestry industry remains cost competitive in the international market. This thesis focuses on ways to better understand and improve cable logging methods by specifically focusing on rigging configurations. The investigation was conducted through a comprehensive literature review, an industry survey to establish current use and preferences, a Delphi survey with experts to establish actual advantages and disadvantages, scale model testing to establish some fundamental knowledge of tension to deflection relationship, and finally a series of targeted case studies to establish both productivity and skyline tension in actual operations. Each of these aspects of the research topic employed different methodology. The literature review highlighted the most relevant research relating to cable logging world-wide spanning nearly a century. Various research papers, manuals, books and computer software were summarized. While many aspects of cable yarding operations have been investigated, much of it focusing on various aspects of operational efficiency through case studies, there is very limited information with regard to rigging configurations. The survey of 50 cable logging practitioners determined what rigging configurations were commonly used in New Zealand. It includes their perceived advantages and disadvantages for varying levels of deflection, but also for specific scenarios such as pulling away from native forest boundaries and flying logs over a stream. Results showed that there were many conflicting perceptions about rigging configuration options. Using an expert panel, a Delphi process was used to derive consensus on what advantages were truly unique to each configuration. This allowed the longer lists of perceived advantages from the industry survey to be pared down to a concise list of ad/disadvantages that will be used in the updating of the Best Practice Guidelines for Cable Logging. To increase our fundamental understanding of tension / payload / deflection relationships, an experiment was conducted in a controlled environment. Using a model yarder in a lab and continuous tension and video recording devices, the dynamic skyline behavior of three similar configurations were tested: North Bend, South Bend and Block in the Bight. The tensions were compared by use of a two-way analysis of variance, which indicated configuration and choker length were significant variables in some but not all of the dynamic load tests. Results also showed that some configurations performed better than others in minimizing the shock loads due to dropping into full suspension, impact with ground objects, and breakout during bridling. Finally, a series of eight studies were conducted on targeted logging operations where relevant stand and terrain parameters were related to the continuous skyline tension monitoring, and recording of productivity through time study. The three targeted configurations included (1) North Bend, (2) Standing skyline using a motorized slack-pulling carriage and (3) a live skyline using a motorized grapple carriage. Results showed that peak and average tensions, as well as amplification factors and the payload to tension relationship, varied between configurations. The study also showed that tensions could be collected to compute measures of payload and tension efficiency, which provided insight into operational performance. The safe working load was exceeded in 53% of all cycles studied and across seven of eight study sites and 14 of 16 spans. Cycle times were significantly different between rigging configurations and that production information could be used to compute measures of labor and energy consumption as well as payload and tension efficiency; which also provide insight into operational performance. The industry should give serious consideration to the use of tension monitors. Tension monitors have many benefits and have the potential to improve cable logging operations in New Zealand. Monitoring tensions can help one learn new techniques or methods (i.e. rigging configurations), help improve payload analysis software for future planning and help evaluate new technology and machinery.
98

Odpovědnost dopravce v mezinárodní přepravě zboží se zaměřením na přepravu námořní / The liability of the carrier in international carriage of goods (focused on carriage of goods by sea)

Lojda, Jiří January 2013 (has links)
The liability of the carrier in international carriage of goods is a classical issue, which is well known, but still actual. The increasing intensity of international trade has impact on the demand for the transport services. Different rules in different legal systems constitute a hindrance for a proper functioning of international transport services. Nowadays, this problem is well solved by the international conventions containing certain rules, regarding contract of carriage in international transport of goods. However, these conventions govern the contract of carriage only in particular mode of transport which is the reason why it is necessary to describe the liability of the carrier in all these particular modes of transport. The starting point of this thesis is to describe the applicable sets of rules, which can govern the contract of carriage in international transport. Today, the relation among these sets of rules can appear be genuinely complicated. The most crucial point seems to solve the problem of relation between the conventions containing certain rules regarding contract of carriage and the legislation of the EU. In the EU, the most important sets of rules are Regulation (EC) No. 593/2008 of the European Parliament and of the Council of 17 June 2008 on the law applicable to...
99

Tipagem molecular de Streptococcus pneumoniae isolados da nasofaringe de crianças no contexto da vacinação pneumocócica / Molecular typing of pneumococcal isolated from the nasopharyngeal from children

ROCHA, Cristyane Gonçalves Benicio Bastos 18 February 2010 (has links)
Made available in DSpace on 2014-07-29T15:26:20Z (GMT). No. of bitstreams: 1 TeseCristyaneBenicio2010.pdf: 531193 bytes, checksum: 9a3d68036fe340ca60db84cb20f7066b (MD5) Previous issue date: 2010-02-18 / Objectives (i) Present review article focusing on pneumococcal vaccines and carriage; (ii) to validate sequential multiplex PCR for identifying pneumococcal capsular serotypes from children attending day-care centers; (iii) determine the multilocus sequence typing; (iv) to identify the capsular types of multiple colonies of S. pneumoniae isolates from a single sample of nasopharyngeal secretions of children attending day-care centers in Goiânia. Materials and Methods S. pneumoniae was obtained from health children less than 5 years old attending 62 day care centers of Goiânia. The laboratory procedures were performed according to WHO recommendations. Were selected 217 isolates (penicillin resistant and sensitive) for capsular typing by multiplex PCR technique. MLST was performed for 55 isolates representing the serotypes detected and the different susceptibility patterns for penicillin. Quellung reaction was used for typing isolates serotypes 6A, 6B, 18C and the isolates not typed by multiplex PCR. For 28 presumptive pneumococcal positive NP swabs, 3 colonies were picked to acess possible serotype diversity. Eighty four pneumococci were identified by conventionally procedure and multiplex PCR was performed. Results Serotypes were deduced for 177/217 (81.6%) of the pneumococcal. The most frequent serogroups/serotypes were 14, 6, 23F, 19F and 18. Multiple serotypes were detected in 13 specimens. Were found 19 MLST types and two new ST. Forty (18.4%) were not serotyped by the multiplex PCR and quellung reaction. The analysis of three colonies from the same NP permitted the detection of differente serotypes in 7/28 (25%) NP samples. Conclusion (i) The multiplex PCR is simple and cost-effective method for detecting multiple serotypes in nasopharyngeal isolates; (ii) and thus might be useful for the monitoring of pneumococcal colonization over time; (iii) the use of multiplex PCR can further broaden our understanding of the dynamics of pneumococcal carriage, including multiple serotypes, the effect of vaccination on carriage, and transmission, as well as surveillance of IPD and co-colonization. / Objetivos: (i) Apresentar uma revisão focando as vacinas pneumocócicas e o portador de S. pneumoniae na nasofaringe; (ii) realizar a tipagem capsular de pneumococos colonizadores de nasofaringe de crianças de creches pela técnica de multiplex PCR; (iii) identificar o perfil MLST dos pneumococos isolados na nasofaringe; (iv) identificar os tipos capsulares de múltiplas colônias de S. pneumoniae isolados de uma única amostra de secreção da nasofaringe de crianças que frequentam creches do município de Goiânia pela técnica de multiplex PCR. Material e Métodos: Um estudo de prevalência de portador de pneumococo foi conduzido de agosto a dezembro de 2005, em crianças de dois a 59 meses de idade, atendidas em 62 creches em Goiânia. Os procedimentos laboratoriais para isolamento e identificação dos pneumococos foram realizados de acordo com as técnicas recomendadas pela Organização Mundial de Saúde. Foram selecionados 217 isolados (resistentes e sensíveis à penicilina) para a tipagem capsular pela técnica de multiplex PCR. O perfil MLST foi realizado para 55 isolados, representando os sorotipos detectados e os diferentes perfis de suscetibilidade à penicilina. A reação de Quellung foi usada para tipar os sorotipos 6A, 6B e 18C e os isolados não tipados pelo multiplex PCR. Para a análise de múltiplas colônias de S. pneumoniae, utilizou-se 28 amostras positivas para pneumococo, das quais se recuperou 3 colônias de cada placa de ágar sangue, totalizando 84 colônias, que foram submetidas aos testes de tipagem fenotípica e caracterização capsular pela técnica de multiplex PCR. Resultados: Cento e setenta e sete sorotipos em duzentos e dezessete (177/217), totalizando 81,6% dos pneumococos foram tipados. Os sorotipos mais freqüentes foram 14, 6, 23F, 19F e 18. Foram identificadas múltiplas colônias em 13 amostras de nasofaringe. Foram observados 19 tipos MLST e dois novos tipos de seqüência (ST). Quarenta (18,4%) dos isolados não foram tipados pelo multiplex PCR e todos não tipados pela reação de Quellung. A análise de múltiplas colônias de S. pneumoniae pela técnica de multiplex PCR permitiu a detecção de mais de um tipo em 25% (7/28) das amostras. Conclusões: (i) O método de multiplex PCR mostrou-se seguro e simples na detecção de diferentes tipos capsulares incluídos na reação, além de mais barato; (ii) representou uma valiosa ferramenta em investigações de vigilância de pneumococos; (iii) Aplicação da técnica multiplex PCR permitiu o conhecimento da diversidade genética de pneumococos colonizadores da nasofaringe, detectando a dinâmica da colonização desta bactéria na população, incluindo a colonização por múltiplos sorotipos; a substituição ou mudança de sorotipo como resultado da vacinação; como também vigilância das doenças pneumocócicas invasivas.
100

Prevalência e determinação dos sorotipos circulantes de Streptococcus pneumoniae em crianças que frequentam creches no município de Goiânia-GO / Prevalence and determination of current serotypes of Streptococcus pneumoniae in children attending in day care centers in Goiânia-GO

Guerreiro, Tainá Carvalho 08 July 2015 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-09T13:25:07Z No. of bitstreams: 2 Dissertação - Tainá Carvalho Guerreiro - 2015.pdf: 1793254 bytes, checksum: b06a919b2f95dde4661fe77445d3668c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-09T13:27:31Z (GMT) No. of bitstreams: 2 Dissertação - Tainá Carvalho Guerreiro - 2015.pdf: 1793254 bytes, checksum: b06a919b2f95dde4661fe77445d3668c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-09T13:27:31Z (GMT). No. of bitstreams: 2 Dissertação - Tainá Carvalho Guerreiro - 2015.pdf: 1793254 bytes, checksum: b06a919b2f95dde4661fe77445d3668c (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-07-08 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Streptococcus pneumoniae remains as a major cause of childhood morbidity and mortality worldwide, especially in developing countries. Nasopharyngeal colonization is the key of the development of pneumococcal diseases as well as for horizontal spread of this pathogen in the community. Children are the main reservoir of S. pneumoniae and act as vectors in the transmission chain of this microorganism. Pneumococcal conjugate vaccines protect against pneumococcal disease caused by vaccine serotypes, also contributes to the protection against colonization by the same serotypes. In 2010, PCV10 was introduced in the childhood immunization program of Brazil. This is a population-based study that was conducted immediately after the introduction of the vaccine in order to determine the carriage rate of this pathogen in children attending in day care centers in Goiania. These data may be used as a predictor for evaluating the dynamic of the circulating serotypes into the community after the vaccine introduction. Between October and November 2010, nasopharyngeal swabs were collected from 853 children ranging from 36 to 59 months attending in day care centers in Goiania. Isolation and identification of S. pneumoniae were done after the incubation step on broth-enriched for 6 h and posterior plating on blood agar. Isolates that were α-haemolytic, optochin-sensitive and soluble in bile were identified as S. pneumoniae. The isolates were serotyped by cmPCR. The database had been built with the statistical program SPSS (Chicago, IL, USA) version 18.0. The possible risk factors were assessed by multivariate Poisson regression. The level of probability of 0.05 (two-tailed) was used to determine statistical significance. The prevalence of pneumococcus carrier was 57.6% (CI95%: 54.2% - 60.9%). According to the multivariate Poisson regression analysis, children aged 36-47 months (IRR: 1.117; CI95%: 1.007-1.238; p: 0.035) and children in whose houses had four or more residents (IRR: 1.1214; CI95%: 1.078-1.368; p 0.001) were considered risk factors independently associated to pneumococcal colonization. The variable family income equal to or greater than three minimum wages was considered a protective factor independently associated to pneumococcal colonization (IRR: 0.787; CI95%: 0.627-0.990; p 0.041). The most prevalent serotypes and serogroups founded were 6A/6B/6C/6D (n=80; 16.3%), 14 (n=47; 9.6%), 23F (n=46; 9.4%), 19F (n=43; 8.8%), 15B/15C (n=30; 6.1%), 11A/11D (n=28; 5.7%), 3 (n=22; 4.5%) and 19A (n=16; 3.3%). Our results showed a high prevalence of pneumococcal colonization among the study population, indicating that colonization by this microrganism is common among children, especially in environments that favor crowding. The main serotypes/serogroups are cover by PCV10. / Streptococcus pneumoniae é o patógeno responsável pelas maiores taxas de morbidade e mortalidade em crianças, principalmente em países em desenvolvimento. A colonização da nasofaringe é a chave para o desenvolvimento das doenças pneumocócicas, bem como para a transmissão horizontal desse patógeno na comunidade. Crianças são o principal reservatório de S. pneumoniae e atuam como vetores dentro da cadeia de transmissão desse microrganismo. As vacinas pneumocócicas conjugadas (PCV) protegem contra as doenças pneumocócicas causadas pelos sorotipos vacinais, atuando também na proteção contra a colonização pelos mesmos sorotipos. Em 2010, o Brasil introduziu a PCV10 no programa de imunização infantil. Este trabalho é um estudo de base populacional que foi conduzido imediatamente após a introdução da PCV10 para determinar a taxa de portador desse patógeno em crianças não vacinadas que frequentam creches no município de Goiânia. Esses dados poderão ser utilizados como linha de base epidemiológica para avaliação da dinâmica dos sorotipos circulantes na comunidade após a introdução da vacina. Foram coletados, nos meses de outubro e novembro de 2010, 853 swabs de secreção da nasofaringe em crianças entre 36 a 59 meses que frequentavam creches no município de Goiânia. Para o isolamento e identificação de S. pneumoniae as amostras foram incubadas por 6 h em caldo enriquecido e semeadas em ágar sangue. Colônias α-hemolíticas sensíveis à optoquina e à bile foram identificadas como S. pneumoniae. Os isolados foram sorotipados por PCR multiplex convencional. A base de dados foi construída com o programa estatístico SPSS (Chicago, IL, USA) versão 18.0. Os possíveis fatores de risco foram avaliados por regressão de Poisson multivariada. O nível de probabilidade de 0,05 (bi-caudal) foi utilizado para determinar a significância estatística. A prevalência de portador do pneumococo foi de 57,6% (IC95%: 54,2% - 60,9%). De acordo com a análise multivariada crianças com idade entre 36-47 meses de idade (IRR: 1,117; IC95%:1,007 – 1,238; p= 0,035) e crianças em cujos domicílios haviam quatro ou mais pessoas residentes (IRR: 1,1214; IC95%: 1,078 – 1,368; p= 0,001) foram considerados fatores de risco independentemente associados para a colonização pneumocócica. A variável renda familiar igual ou superior a três salários mínimos foi considerada um fator protetor independentemente associado para a colonização pneumocócica (IRR: 0,787; IC95%: 0,627 – 0,990; p= 0,041). Os sorotipos/sorogrupos mais prevalentes foram 6A/6B/6C/6D (n=80; 16,3%), 14 (n=47; 9,6%), 23F (n=46; 9,4%), 19F (n=43; 8,8%), 15B/15C (n=30; 6,1%), 11A/11D (n=28; 5,7%), 3 (n=22; 4,5%) e 19A (n=16; 3,3%). Nossos resultados mostraram uma alta prevalência de colonização por pneumococo entre a população estudada, indicando que a colonização por esse microrganismo é comum entre crianças, principalmente em ambientes que favorecem a aglomeração. Os principais sorotipos/sorogrupos encontrados são contemplados pela PCV10.

Page generated in 0.0506 seconds