The aim of the research presented in this dissertation was to further the implementation of push-pull for control of Eldana saccharina on sugarcane in the Midlands North region, KwaZulu-Natal, South Africa. Eldana saccharina, an indigenous stem borer, is the most damaging pest of sugarcane in South Africa, and sustainable control has still not been achieved. The push-pull strategy, a form of habitat management, has been developed for E. saccharina and is recommended as part of an integrated pest management (IPM) approach. Implementation of this strategy for both large- and small-scale farmers was facilitated through mixed methods social research. It included a novel exploratory network analysis to understand the process of technology adoption by farmers. Surveys showed that large-scale farmers have a good knowledge of E. saccharina, IPM and push-pull but that they needed more practical knowledge for implementation of the strategy. Farmers recommended experiential learning opportunities such as field days and model farms to get to know more about this technology. Despite demonstrating a positive attitude towards push-pull, farmers perceived it to be a ‘hassle’ and this is potentially the biggest barrier to its adoption. However, with suitable learning opportunities for farmers and good support for planting inputs, implementation of push-pull is likely to succeed. Sugarcane was shown to play an important role in the livelihoods and farming systems of small-scale growers. They did not perceive E. saccharina as a serious production constraint and had poor knowledge of the pest and its control. Extension for small-scale growers in this region should focus primarily on weed management and on reducing input costs, but still raising awareness of the increasing threat of E. saccharina. On-farm push-pull field trials showed a significant reduction of E. saccharina damage on two farms. Mean percentage damaged internodes decreased from 4.1% to 2.7% and from 1.7% to 1.1% in the presence of the repellent grass species, Melinis minutiflora. Where farmers did not manage their crops well, push-pull was not effective. It is therefore crucial that push-pull within an IPM framework be implemented together with good crop management practices. Stem borer surveys in wetlands on sugarcane farms revealed a high diversity of indigenous stem borers and parasitoids, including a stem borer species, Pirateolea piscator, which may pose a threat to crops in the future. These findings, together with a literature review on the significance of on-farm biodiversity and ecosystem services, demonstrated the value which wetlands have for pest management on sugarcane farms. Wetland health assessments were used to develop a tool for farmers to assess and utilise the wetlands on their farms for improved management of E. saccharina. This study highlights the importance of a farmer-participatory approach to implementation of knowledge-intensive farming practices such as push-pull. The importance of wetlands for providing pest regulatory services on sugarcane farms has shown that environmental sustainability needs to become a fundamental principle of farming and agricultural research. Participatory implementation of push-pull, as recommended in this dissertation, could act as a driving force for agroecology in the South African sugar industry and move sustainable farming practices off the pages of journals and manuals onto farmers’ fields. / Thesis (MSc (Zoology))--North-West University, Potchefstroom Campus, 2013

The common profiled steel cladding systems used in Australia and its neighboring countries are made of very thin (0.42 mm) high strength steel (G550 with a minimum yield stress of 550 MPa) and are crest-fixed. However, these claddings often suffer from local pull-through failures at their screw connections during high wind events such as storms and cyclones. Past experience and researches have shown that the loss of steel roofs has often occurred due to local pull-through failures of their screw connections under uplift or suction loading. Loss of claddings always led to a progressive collapse of the entire building. This situation is continuing because of the lower priority given to the design of roof and wall cladding systems. At present, steel design codes do not provide guidelines for the design of crest-fixed steel roof or wall claddings. Past research has shown that European and American recommendations for steel claddings cannot be used for Australian crest-fixed cladding systems as they were developed mainly for valley-fixed claddings subjected to gravity loading instead of crest-fixed claddings subjected to wind uplift/suction loading. Therefore at present the design of thin steel cladding systems is based on laboratory tests and is expensive. These situations inhibit the innovative design and advances in the steel cladding industry. Since the local pull-through failures in the less ductile G550 steel claddings are initiated by transverse splitting at the fastener hole, analytical studies have not been able to determine the pull-through failure loads accurately. Therefore in the first stage of this research an appropriate fracture/splitting criterion was developed using a series of large scale and small scale experiments of crest-fixed steel claddings. A shell finite element model of crest-fixed steel cladding was then developed that included the new fracture/splitting criterion and advanced features such as hyperelastic material modelling, contact simulations, residual stresses and geometric imperfections. The improved finite element analyses were able to model the pull-through failures associated with splitting as evident from the comparison of their results with the corresponding full-scale experimental results. An extensive series of parametric studies considering the effects of material properties and geometric parameters of the two commonly used trapezoidal cladding profiles was undertaken using finite element analysis. Appropriate design formulae for the pull-through and dimpling failure load of trapezoidal profiles were then derived for optimization purposes and to simplify the current design method. This will then lead to modification and optimisation of cladding profiles to satisfy the requirements of both strength (safety during cyclones and storms) and economy. This thesis presents the details of large scale experimental studies undertaken and the results including the criterion for the splitting/fracture failure of high strength steel cladding systems. It describes the many advances made in the finite element modelling of crest-fixed steel cladding systems including the effects of localised pull-through and dimpling failures. Finally, it presents a simple design method for trapezoidal steel cladding systems under wind uplift or suction loading.

Research Doctorate - Doctor of Philosophy (PhD) / Inserting fibre reinforced polymer (FRP) strips into pre-cut grooves in the surface of masonry walls is an emerging technique for the retrofit of unreinforced masonry (URM) structures. This method, known as near surface mounting (NSM), provides significant advantages over externally bonded FRP strips in that it has less of an effect on the aesthetics of a structure and can sustain higher loading before debonding. As this technique is relatively new, few studies into the behaviour of masonry walls strengthened using this technique have been conducted. A combined experimental and numerical program was conducted as part of this research project to study the in-plane shear behaviour of masonry wall panels strengthened with NSM carbon FRP (CFRP) strips. In this project the FRP strips were designed to resist sliding along mortar bed joints and diagonal cracking (through mortar joints and brick units). Both of these failure modes are common to masonry shear walls. Different reinforcement orientations were used, including: vertical; horizontal; and a combination of both. The first stage of the project involved characterising the bond between the FRP and the masonry using experimental pull tests (18 in total). From these tests the bond strength, the critical bond length and the local bond-slip relationship of the debonding interface was determined. The second stage of the project involved conducting diagonal tension/shear tests on masonry panels. A total of four URM wall panels and seven strengthened wall panels were tested. These tests were used to determine: the effectiveness of the reinforcement; the failure modes; the reinforcement mechanisms; and the behaviour of the bond between the masonry and the FRP in the case of a panel. The third stage of the project involved developing a finite element model to help understand the experimental results. The masonry was modelled using the micro-modelling approach, and the FRP was attached to the masonry model using the bond-slip relationships determined from the pull tests. Reinforcement schemes in which vertical FRP strips were used improved the strength and ductility of the masonry wall panels. When only horizontal strips were used to reinforce a wall panel, failure occurred along an un-strengthened bed joint and the increase in strength and ductility was negligible. The vertical reinforcement prevented URM sliding failure by restraining the opening (dilation) of the sliding cracks that developed through the mortar bed joints. The finite element model reproduced the key behaviours observed in the experiments for both the unreinforced and FRP strengthened wall panels. This model would potentially be useful for the development of design equations.

Research Doctorate - Doctor of Philosophy (PhD) / Inserting fibre reinforced polymer (FRP) strips into pre-cut grooves in the surface of masonry walls is an emerging technique for the retrofit of unreinforced masonry (URM) structures. This method, known as near surface mounting (NSM), provides significant advantages over externally bonded FRP strips in that it has less of an effect on the aesthetics of a structure and can sustain higher loading before debonding. As this technique is relatively new, few studies into the behaviour of masonry walls strengthened using this technique have been conducted. A combined experimental and numerical program was conducted as part of this research project to study the in-plane shear behaviour of masonry wall panels strengthened with NSM carbon FRP (CFRP) strips. In this project the FRP strips were designed to resist sliding along mortar bed joints and diagonal cracking (through mortar joints and brick units). Both of these failure modes are common to masonry shear walls. Different reinforcement orientations were used, including: vertical; horizontal; and a combination of both. The first stage of the project involved characterising the bond between the FRP and the masonry using experimental pull tests (18 in total). From these tests the bond strength, the critical bond length and the local bond-slip relationship of the debonding interface was determined. The second stage of the project involved conducting diagonal tension/shear tests on masonry panels. A total of four URM wall panels and seven strengthened wall panels were tested. These tests were used to determine: the effectiveness of the reinforcement; the failure modes; the reinforcement mechanisms; and the behaviour of the bond between the masonry and the FRP in the case of a panel. The third stage of the project involved developing a finite element model to help understand the experimental results. The masonry was modelled using the micro-modelling approach, and the FRP was attached to the masonry model using the bond-slip relationships determined from the pull tests. Reinforcement schemes in which vertical FRP strips were used improved the strength and ductility of the masonry wall panels. When only horizontal strips were used to reinforce a wall panel, failure occurred along an un-strengthened bed joint and the increase in strength and ductility was negligible. The vertical reinforcement prevented URM sliding failure by restraining the opening (dilation) of the sliding cracks that developed through the mortar bed joints. The finite element model reproduced the key behaviours observed in the experiments for both the unreinforced and FRP strengthened wall panels. This model would potentially be useful for the development of design equations.

Universiẗat, Diss.--St. Gallen, 1998. / Literaturverz. S. 225 - 249.

Title from first page of PDF document. Includes bibliographical references (p. 154-156).

Introdução: A gastrostomia percutânea endoscópica (PEG) é utilizada como via de nutrição para pacientes sem capacidade de utilizar a via oral para manter ingestão suficiente. A disfagiaé uma das principais razões para a indicação da PEG, sendo geralmente atribuída a processos neurodegenerativos. Diferentes técnicas e tipos de sonda são utilizadas para confecção da PEG. A técnica de Tração é o método original, na qual a sonda é tracionada a partir de uma pequena incisão na parede abdominal, através a boca e do esôfago até estar posicionada junto da parede gástrica. A técnica de punção com gastropexia é uma variante da técnica de punção original, na qual a sonda não passa pela cavidade oral. Nesta técnica, após fixação do estômago na parede abdominal com uso de pontos, a sonda é introduzida diretamente através da parede abdominal sob visão endoscópica. De acordo com a técnica, diferentes modelos de sondas podem ser utilizadas, cada uma com diferentes tipos de retentores internos. Os retentores internos maiscomuns são: em forma de diamante, em forma de cogumelo, disco rígido e balão. Possivelmente, tanto a técnica de inserção como os modelos de sondas e retentores utilizados podem estar associados a diferentes desfechos. O objetivo deste estudo foi avaliar a incidência podem estar associados a diferentes desfechos. O objetivo deste estudo foi avaliar a incidência. Métodos: Foi realizada uma coorte histórica na qual foram incluídos todos os pacientes maiores de 18 anos submetidos à colocação de uma primeira PEG entre janeiro de 2010 e dezembro de 2015 no Hospital Moinhos de Vento, um hospital privado em Porto Alegre, sul do Brasil. Os dados foram coletados em formulário padronizado através de uma busca no sistema informatizado da Instituição. Para complementação dos dados foi realizada uma busca nos prontuários digitalizados, e em algumas situações realizado contato telefônico. Resultados: Foram identificados 245 pacientes, sendo 200 submetidos a técnica de tração (Pull) e 45 à técnica de punção com gastropexia (Push com gastropexia). A média da idade foi 80,3±13,3 anos. Cento e trinta e quatro (54,7%) pacientes eram do sexo feminino. O período médio de seguimento foi de 17,2±14,6 meses. A indicação mais comum foi doença neurodegenerativa (62,4%), seguido por acidente vascular cerebral (AVC) (16,3%). Todos os pacientes realizaram profilaxia com antibiótico no dia do procedimento. A mediana de dias de internação pós PEG foi de 8 dias. O modelo de sonda mais utilizado foi o retentor em forma de diamante (51,8/%). A colocação da PEG foi bem-sucedida em 99,6% dos casos. A mortalidade geral foi de 42,4% (104/245) durante o período de seguimento. Nenhum óbito foi atribuído diretamente a complicações relacionadas ao procedimento. Entretanto, três pacientes faleceram dentro de 48 horas após o procedimento: um por sepse respiratória, outro por parada cardiorrespiratória e o terceiro que realizou a PEG ambulatorial teve morte súbita no domicílio. A taxa de complicações (maiores ou menores) foi de 23,6%, sendo a mais frequente, a retirada acidental da sonda, que ocorreu em 17,1% dos pacientes em algum momento do seu seguimento. Não foi observada diferença entre as técnicas de realização da PEG gastrostomia com a incidência desta complicação. O tempo até a retirada acidental da sonda foi menor entre os pacientes cujas sondas tinham o retentor interno em forma de diamante em relação aos demais retentores (p = 0,02). Sepultamento do retentor interno (Buried Bumper Syndrome) ocorreu em 5,4% dos casos, todos submetidos a técnica de tração (p = 0,08). Pacientes portadores de sonda com retentor em forma de diamante apresentaram maior incidência de complicações gerais (p = 0,02) e de retirada acidental (p = 0,01), comparativamente aos pacientes portadores de sondas com outros tipos de retentor. Conclusões: A PEG é uma técnica segura, com baixa taxa de mortalidade diretamente associada ao procedimento. Entretanto, devido a população na qual o procedimento é realizado, a mortalidade geral é elevada. Complicações menores são frequentes, independentemente da técnica ou tipo de sonda utilizada, porém a técnica e o tipo de sonda parecem associadas a um perfil diferente de complicações. Perspectivas: O desenvolvimento da técnica, o desenvolvimento de materiais com melhor perfil de segurança e, especialmente, o aprimoramento das orientações e cuidados pós-gastrostomia são necessários para reduzir a incidência de complicações em pacientes submetidos a esse tipo de procedimento. Novos estudos comparando de maneira prospectiva e randomizada diferentes técnicas e modelos de sonda são necessários para determinar se há uma técnica ou modelo a ser utilizado como primeira escolha.

Tittle: Description quadrupedal locomotion diagonal pattern in specific sport activity (rope climbing, walking, pull-up) Aim of work: The aim is to find a description kvadrupedal locomotion diagonal pattern with rope climbing and its motion pattern compared with the motion pattern of walking and pull-up. Methods: This work is descriptively-association study with quantitative and qualitative analysis. The dates were measured by surface electromyography and 2-D video-analysis. Results: Alternating activation of upper extremities (rope climbing without the lower extremities), we proved that the movement supporting lower extremities is quadruped locomotion diagonal pattern. Symmetric work of upper extremities (pull-up) is not in response at lower extremities quadruped locomotion diagonal pattern. Key words: Electromyography (EMG), quadruped, diagonal pattern, rope climbing, pull-up, walking

This study aims to analyse women’s self-employment in five regions of Europe, namely Northern Europe, Eastern Europe, Southern Europe, North-West Europe and Western Europe in two years, 2002 and 2016. To assess the factors affecting women’s self-employment in Europe we base our analysis on push and pull theory and as far as the quantitative part is concerned we estimate a probit model. Our research questions are the following: What socio-economic factors influence women to enter self-employment in the five regions of Europe? How are these factors related to the push and pull theory? Is there a trend of convergence over time in the five European regions studied? The main findings are that being women decreases the probability to become self-employed in the five European regions, except in the Northern part of Europe. The result suggests that women more often than men are pushed into self-employment as they have to balance work with family. Being young (18-35) also decreases the probability of being self-employed compared to middle age individual (36-50) in the year 2002 and 2016. Individuals with low and medium-skill level have a lower probability of being self-employed in comparison to the individual with high skill. Regarding the research questions, this study found that variable age (18-36), age (51-65), married, children, medium education, high education, low skill and high skill are factors that influence women in their decision to become self-employed. Observing the change over time of self-employment, we found that the probability increases being selfemployed in Southern Europe whereas it decreases in Northern Europe.

Made available in DSpace on 2016-12-06T17:07:13Z (GMT). No. of bitstreams: 1 RESUMO.pdf: 26325 bytes, checksum: b3675c6043e597d4b7943a6b80a68275 (MD5) Previous issue date: 2001-12-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A variety of reconstructive surgical procedures rely on the strength improvement of tendon-to-tendon linkage. Thus, methods to improve tendon ruptures may allow earlier rehabilitation and fast return to the daily living. The purpose of this study was to evaluate the mechanical strength of aquilles tendon 2-mm defect in male rabbits. The created gap was filled with bovine collagen (biomaterial) in nine specimens and a suture with no filling in other nine specimens. The other aquilles tendons were the control group as pattern of normality. In all eighteen tendons (eighteen animals) the strength were tested in a material testing machine for a pull-out strength. Ultimate strength and dislocation were analyzed in all groups. One-way analysis of variance (ANOVA) at a p£ 0.05 was used to compare the biomechanical data in the sixth week period of time. There were no obvious slipping at the interface between the clamp and the muscle-tendon fixation. There was no significantly difference among the groups. For the strength variable p=0.0467 and for the displacement p=0.1950. The coefficient of variation of 30% for the control group, 25% for the biomaterial group and 18% for the suture group when analyzing the tendon strength. In the displacement data, the control group presented a coefficient of variation of 37%, biomaterial group of 25% and the 42% for the control group. The presented data have not shown any improvement using biomaterial. However, the collagen group has shown similar curves compared to the control group. / O presente estudo teve como objetivo avaliar o comportamento biomecânico do tendão calcaneano de coelhos, quando utilizado um componente biológico para o preenchimento de uma falha. Os biomateriais são substâncias biologicamente ativas, que apresentam efeito osteogênico e formador de partes moles, isto é, ativam a formação de osso e colágeno novos nos organismos vivos. Neste estudo o biomaterial foi o colágeno bovino. A amostra foi caracterizada por dezoito coelhos da raça Nova Zelândia, adultos, machos em que foi criada uma falha cirúrgica de 2 mm no tendão calcaneano de todos os animais. Em nove animais foi realizada simples sutura sem biomaterial, nos restantes nove animais foi realizada a implantação dos biomateriais nas falhas criadas. No período de seis semanas estes animais foram sacrificados e os tendões submetidos ao teste de tração. A comparação foi utilizada pelo tendão não operado, como forma de obter-se o padrão de normalidade da resistência dos tendões. Foram utilizadas as garras para o ensaio de tração, próprias da máquina de ensaios biomecânicos. Os resultados da carga máxima aplicada para a ruptura destes espécimes e o deslocamento, a partir da curva carga-deslocamento foram registrados e avaliados o comportamento biomecânico destes espécimes. Utilizando-se a análise da variância (ANOVA) com um p£ 0,05 não foram observados diferenças estatisticamente significantes entre os grupos de estudo e o grupo controle. O coeficiente de variação (CV%) em relação à variável carga máxima à falência no grupo controle foi de 30%, no grupo biomaterial 25% e no grupo sutura 18%. Na análise do grau de deslocamento, o grupo controle apresentou um CV de 37%, o biomaterial de 25% e 42% para o grupo controle. Em análise do coeficiente de variação acumulado, houve uma tendência para estabilização da curva nos grupos apresentados. Os dados acima apresentados não demonstraram um efeito benéfico na adição do colágeno bovino nestes grupos estudados. Ainda assim, em observação qualitativa, as curvas do grupo biomaterial apresentaram um traçado semelhante aos da normalidade.