The motivation of this work is filtering of elongated curvilinear objects in digital images. Their narrowness presents difficulties for their detection. In addition, they are prone to disconnections due to noise, image acquisition artefacts and occlusions by other objects. This work is focused on thin objects detection and linkage. For these purposes, a hybrid second-order derivative-based and morphological linear filtering method is proposed within the framework of scale-space theory. The theory of spatially-variant morphological filters is discussed and efficient algorithms are presented. From the application point of view, our work is motivated by the diagnosis, treatment planning and follow-up of vascular diseases. The first application is aimed at the assessment of arteriovenous malformations (AVM) of cerebral vasculature. The small size and the complexity of the vascular structures, coupled to noise, image acquisition artefacts, and blood signal heterogeneity make the analysis of such data a challenging task. This work is focused on cerebral angiographic image enhancement, segmentation and vascular network analysis with the final purpose to further assist the study of cerebral AVM. The second medical application concerns the processing of low dose X-ray images used in interventional radiology therapies observing insertion of guide-wires in the vascular system of patients. Such procedures are used in aneurysm treatment, tumour embolization and other clinical procedures. Due to low signal-to-noise ratio of such data, guide-wire detection is needed for their visualization and reconstruction. Here, we compare the performance of several line detection algorithms. The purpose of this work is to select a few of the most promising line detection methods for this medical application

Tender vessels in the United States will soon need to comply with new safety regulations as mandated by the Coast Guard Authorization Act of 2010. This thesis focuses specifically on assisting in the formation of an Alternative Safety Compliance Program (ASCP) for the unique tender vessel fleet and seeks to understand why tender vessels experience fatalities and vessel casualties. By analyzing data of tendermen fatalities and tender vessel casualties between 2000 and 2012, the report sheds light on the realities of these incidents. Among other findings, the data show that the most common cause of vessel casualty was striking rocks or the ocean floor, and the most common human error was falling asleep at the helm. This thesis then proposes potential regulations that would be economically feasible and realistic for tenders by comparing the casualty data to the reported financial realities of current tender vessels. Notably, the analysis indicates that applying the current Alternative Compliance and Safety Agreement (ACSA) to tenders would not be beneficial. Ultimately, the proposed regulations herein should act as a foundation for a discussion regarding an alternative compliance agreement, as the final agreement will be reached through a much greater dialogue between many involved parties, including tendermen, regulators, safety compliance experts, and others.

Kemikalier hanteras i det dagliga arbetet ombord. Syftet med den här studien var att ta reda på hur kemikalier hanteras ombord på en svensk passagerarfärja. Frågeställningarna koncentrerades på produkt- och metodval, kommunikation och tillämpning av rutiner och instruktioner samt riskmedvetenhet hos besättningen. Studien genomfördes som en enfallsstudie och bestod av dokumentanalyser, observationer och intervjuer med besättningsmedlemmar. Resultatet visar att informanterna på däcks- och maskinavdelningarna hade stora möjligheter att påverka arbetssituationen vad gäller hantering av kemikalier till skillnad från informanten på intendenturavdelningen som enbart hade begränsad möjlighet att påverka. En god kännedom om säkerhetsdatablad fanns hos samtliga informanter, liksom en hög riskmedvetenhet. Den personliga skyddsutrustningen prioriterades högt och sågs som en viktig del för att minska riskerna med kemikaliehanteringen. Den slutsats som drogs var att det praktiska arbetet med kemikalier ombord fungerade tillfredsställande, men dokumentationen kan förbättras i form av tydligare instruktioner och utförligare information. / Chemicals are a part of the daily work on board. The purpose of this study was to find out about the handling of chemicals on board a Swedish passenger ferry. The research questions were focused on choice of products and methods, communication and application of routines and instructions and risk awareness among the crew members. The study was carried out as a single-case study and consisted of analysis of documents, observations and interviews with crew members. The results show that the informants on the deck and engine departments had ample opportunity to influence the working situation in regards to handling of chemicals. The informant from the service department had limited ability to influence. All informants had a good knowledge about material safety data sheets and a high awareness about risks with chemicals. The personal protective equipment was highly prioritized and regarded as a vital part to minimize the risks with chemical handling. The conclusion drawn was that the practical work with chemicals on board functioned satisfactorily, but the documentation could be improved in terms of clearer instructions and more detailed information.

Till sjöss är den hierarkiska organisationsstrukturen den vanligast förekommande. Detta sträcker sig från befälhavaren till den individuella sjömannen. Överstyrman, nummer två i däcksbefälsordningen, har flera olika ansvarsområden. Några vanliga exempel är bland annat att prioritera underhåll av fartyget, övervaka och leda arbetet på däck samt att ha huvudansvar för lastning och lossning. Med detta i åtanke är det inte svårt att tänka sig att man i denna roll upplever konflikter ombord, både arbetsrelaterade och privata. Syftet med denna studie är att försöka besvara vilka konflikter som är vanligast utifrån en överstyrmans perspektiv samt utreda om överstyrmän i sin roll använder några definierade metoder för att hantera de konflikter som uppstår. Avslutningsvis besvaras också frågan hur benägna överstyrmän är att deltaga i kurser kring utveckling av sin egen konflikthantering. Genom djupintervjuer med aktiva överstyrmän så har slutsatsen dragits att de mest vanliga konflikterna är de som uppstår från små irritationer i vardagen. Dessa mindre konflikter, om de lämnas utan åtgärd, har en tendens att växa och eskalera till större tvister som kräver konflikthantering. Ur ett konflikthanteringsperspektiv så visar undersökningen på att alla överstyrmän använder sig av en fördefinierad konflikthanteringsstrategi. Alla som har deltagit i undersökningen anser att vidare utbildning inom området konflikthantering skulle gynna dem både i deras roll som överstyrman och samtidigt ha en positiv inverkan på ombordkulturen. / At sea, a strict hierarchy is the natural chain of command. This ranges from the captain to the individual sailor. The Chief Officer, second in command on deck, has many areas of responsibility. For instance, he or she is commonly in charge of prioritizing aspects of ship maintenance, supervise and manage crew work-orders and the main responsibility for loading and discharging cargo. With this in mind, it is not hard to imagine that a mustered chief officer will experience a variety of conflicts on-board, both work related and personal. The purpose of this study is to answer what conflicts are the most common from a chief officers perspective on-board a merchant vessel. Also it will gauge if there are any specific conflict management methods that are used by chief officers to advert or intervene in the conflict situations that can arise. The concluding section of this study will look at the possibility and interest for chief officers to attend a course in conflict management to further develop their tools within this area. Through in-depth interviews with active chief officer the result showed that the most common conflicts were perceived as the ones that arose from everyday problems on-board. These minor issues, if left to their own accord, tend to escalate. From a conflict management perspective, all findings indicate that chief officers tend to use a predefined strategy in regards to solving or manage conflicts on-board. However, all respondents agree that further education within the field would surely benefit them as individuals and also the on-board culture as a whole.

Recombinant synthesis of elastin-mimetic proteins has been employed for several decades, however, long-term biocompatibility and biostability of such proteins was not fully defined. We present virtually crosslinked elastin-mimetic proteins which exhibit exceptional biocompatibility and long-term biostability over a period of at least seven months. This report is the first evidence of a non-chemically or ionically crosslinked system that exhibits long-term in vivo stability. Although, physically crosslinked protein-based materials possess a number of advantages over their chemically crosslinked counterparts, physical crosslinks and the related domains so formed may be deformed or damaged at applied stresses lower than those required to disrupt covalent crosslinks. In this regard, we have synthesized a new class of recombinant elastin-mimetic triblock copolymer capable of both physical and chemical crosslinking. We have demonstrated that chemical crosslinking provides an independent mechanism for control of protein mechanical responses. Specifically, elastic modulus was enhanced and creep strain reduced through the addition of chemical crosslinking sites. A number of reports have described the design of synthetic genes, which encode elastin-like proteins for bacterial expression in Escherichia coli. Although advantages with this expression system exist, significant limitations including the lack of eukaryotic post-translational systems, the tendency to sequester mammalian proteins into inclusion bodies, difficult purification protocols, and endotoxin contamination have been noted. We demonstrate the expression of a recombinant elastin-mimetic protein from P. pastoris. A novel synthetic strategy, monomer library concatamerization, was utilized in designing non-repetitive elastin genes for highly repetitive protein sequences. It is likely that this strategy will be useful for creating large, repetitive genes for a variety of expression systems in order to more closely approach the genetic diversity inherent to native DNA sequences. All told, elastin-based protein polymers are a promising class of material characterized by high degree of biocompatibility, excellent biostability, and a tunable range of mechanical properties from plastic to elastic. A variety of options facilitate the processing of these biopolymers into chemically crosslinked or non-crosslinked gels, films, or nanofibers for any of a number of implant applications including structural components of artificial organs and engineered living tissues, carriers for controlled drug release, or biocompatible surface coatings.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 4 uppsatser.

A gestação inicial da égua é um período fascinante que abrange numerosas e intensas mudanças em seu desenvolvimento, muitas das quais são únicas para a espécie equina. Esse desenvolvimento depende da manutenção da função lútea, do estabelecimento de um ambiente uterino e de uma interação precisa e orquestrada entre o concepto e o ambiente uterino. O objetivo deste estudo foi verificar as alterações histológicas do endométrio e a produção histotrófica em éguas cíclicas e prenhes nos dias 7, 10 e 13 pós-ovulação. No primeiro ciclo, biópsias endometriais de 30 éguas foram coletadas no dia 7 (n = 10), 10 (n = 10) e 13 (n = 10) constituindo o grupo éguas cíclicas. No segundo ciclo, as mesmas éguas foram cobertas por um garanhão fértil, acompanhadas diariamente até detectar a ovulação, considerada o dia 0. Foram coletadas biópsias endometriais nos dias7 (n 10), 10 (n 10) e 13 (n 10). Imediatamente após a coleta, o útero foi lavado e as éguas em que foi obtido embrião, foram inseridas no grupo de éguas prenhes. Um maior calibre dos vasos sanguíneos foi observado em prenhez comparados às éguas cíclicas do dia 7 aos 13. No sétimo dia pós-ovulação, uma grande perda de células ciliadas foi evidente no grupo de éguas prenhes, comparadas ao grupo de éguas cíclicas, as células do epitélio endometrial estavam mais protusas e uma pequena quantidade de secreção histotrófica entre as dobras endometriais foi observada. No décimo dia de prenhez, secreção histotrófica glandular e do epitélio luminal estavam mais presentes comparadas às éguas do grupo cíclico. No dia 13 de prenhes, foi observado um grande conteúdo de histotrofo nas aberturas glandulares que estavam cercadas por células ciliares. Ocorreram alterações no ambiente uterino logo após a entrada do embrião no útero. No estroma e no lúmen, essas modificações parecem visar fornecer a nutrição necessária para o desenvolvimento inicial do embrião e estas mudanças nas estruturas celulares irão interagir na sinalização embrionária, futura fixação, implantação e placentação. / The early pregnancy of mare is a fascinating period that encompasses numerous and intense changes in its development, many of which are unique to the equine species. This development depends on the maintenance of the luteal function, the establishment of a favorable uterine environment and a precise and orchestrated interaction between the concept and the uterine environment. The aim of this study was to evaluate histological changes in the endometrium in days 7, 10 and 13 post-ovulation in pregnant and cyclic mares. In the first cycle, endometrial biopsies from 30 cyclic mares (Cyclic group) were collected on days 7, 10 and 13 post-ovulation. In the second cycle, the same mares were bred by a fertile stallion. At days 7, 10 and 13 post-ovulation intrauterine biopsies were collected. Immediately after sample collection, the mare‟s uteri were flushed, and those mares with embryo recovery were assigned to the Pregnant group. A larger blood vessel caliber was observed in pregnant mares than in cyclic from day 7 to 13. On the 7th day a large loss of ciliated cells was evident in the group of pregnant mares in comparison with the Cyclic group and the superficial cells of the endometrium were more protruded, and a small amount of histotrophic material between the folds was observed. On the 10th day of pregnancy, the glandular histotrophic secretion and the secretion of luminal epithelium became more intense than the secretion of cyclic mares. On the 13th day of pregnancy, a very large amount of histotroph was observed within large glandular openings surrounded by ciliated cells. Changes occurred in the uterine environment thereupon the entry of the embryo into the uterus. In the stroma and in the lumen, these modifications seem aim to provide the necessary nutrition for the initial development of the embryo and to promote changes at cellular structures that will interact in the embryonic signaling and future fixation, implantation and placentation.

Vasos de pressão e tubulações são equipamentos essenciais em industrias químicas, petroquímicas, refino de petróleo, entre outras. A operação segura deste tipo de equipamento é um fator determinante, visto que falhas podem variar desde grandes perdas financeiras até consequências catastróficas. Avaliação de descontinuidades encontradas em inspeções podem ser realizadas através de metodologias de fitness for service, as quais são baseadas na mecânica da fratura, que teve grande desenvolvimentos nos últimos 40 anos. Estas metodologias são consagradas como sendo seguras para garantir a integridade de equipamentos em operação. Este trabalho utilizará primeiramente a metodologia de “fitness for service” empregando o guia BS7910 para avaliar um caso de um bocal de oito polegadas de diâmetro unido a um casco de dezesseis polegadas de diâmetro com uma grande descontinuidade do tipo falta de penetração em sua solda. A metodologia de fitness for service será comparada com o resultado do teste experimental, o qual foi realizado através de um teste hidrostático destrutivo monitorado através do ensaio de emissão acústica. Por fim, será realizada uma análise não linear utilizando não linearidade física e geométrica através do método de elementos finitos. A comparação dos resultados numéricos, experimentais e os analíticos obtidos pela aplicação da BS7910 permitiram a obtenção de várias conclusões que são expostas neste trabalho. A metodologia de ajuste ao uso utilizando a BS7910 foi conservativa para o caso estudado. O modo de falha dominante utilizando a BS7910 foi o colapso plástico que foi coerente com o teste experimental. O ensaio de emissão acústica não teve correlação entre a energia acumulada dos sinais captados e a criticidade de descontinuidades entre um bocal e um tampo, o que salientou que para aplicações semelhantes os dados devem ser analisados cuidadosamente uma vez que regiões sujeitas a colapso plástico como no caso do bocal estudado podem emitir sinais de menor intensidade que descontinuidades onde existe a interação entre os modos de fratura e colapso plástico. A análise não linear utilizando não linearidades física e geometria teve o resultado 5,8% maior que a pressão de ruptura no teste experimental que foi de 14,7MPa, o que pode ser considerado um resultado com um bom grau de aproximação. / Pressure vessels and pipes are essential equipment in the chemical, petrochemical, petroleum refining, among others. The safety operation of this equipment is an important aspect, since failures can vary from large financial losses to catastrophic consequences. Evaluation discontinuity found in inspections can be perfomed by fitness for service methodology which is based on fracture mechanics, which had great developments in the last 40 years. These methodologies are known as being the best way to ensure the integrity of equipment while in operation. This work first uses the fitness for service methodology according BS7910 guide to evaluate lack of weld penetration in eight-inch nozzle attached to a shell with sixteen inches in diameter. The methodology of fitness for service was compared with the experimental test result, which was performed by a destructive hydrostatic test monitored by acoustic emission test. Finally, finite element method was performed using nonlinearity physical and geometric tecniques. The comparison of numerical, experimental and analytical results obtained by the application of BS7910 allowed us to obtain several conclusions that are exposed in this work. The methodology using the BS7910 was conservative for the case study. The dominant failure mode using the BS7910 was the collapse of plastic that was consistent with the experimental test. The acoustic emission technique had no correlation between the stored energy of the picked up signals and criticality of discontinuities between a nozzle and a head, which pointed out that for similar applications data must be analyzed carefully since in regions subjected to plastic collapse such as in the case studied nozzle can generate signals of lower intensity that discontinuities where there is an interaction between the modes of fracture and plastic collapse. The nonlinear analysis result using physics and geometry nonlinearities was 5.8% higher than the rupture pressure of the experimental test was 14.7 MPa, being considered a result with a good degree of accuracity.

Diploma work that deals with topic of "Anti - flood measures on chosen parts of the Novohradka river" is divided into theoretical and practical treatise. Theoretical treatise contains specific section that deals with laws relating to flood solutions and general part that explains flood as such and everything it involves. Practical part sums up concrete proposed anti - flood measures but it also mentions personal suggestions and evaluations of so far executed measures. This work should especially attract attention of general public and representatives of interested parties.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to analyze the development of cravina culture in substrate ash rice husk in different vessel sizes and under varying levels of water availability, observing its response as the height of the stems developed, number of nodes per stem; fresh weight and dry weight of stems and number of flower buds developed per stem. The cultivar used in the experiment was a hybrid of series 'Melody', the seedlings were obtained by cutting a die makers deployed specifically for this purpose. The seedlings were first planted in rooting where they remained for 30 days and were then transplanted in black plastic pots, 8 and 18 liters, filled with a substrate of rice husk ash, and kept 100% 80% 60% and 40% of the capacity of water retention of the vessels. Maintenance of the water vessel was performed by the method of weighting, with added amounts of water to keep the vessel in your weight limit. The water consumption of plants was determined by the method of weighing over two crop cycles. Results showed that the water consumption of this species is highly influenced by the weather; is recommend the use vessel of lower capacity and maintenance water in 40% of the capacity to retain water; it is preferable to growing the cravina in just a cycle, since the rods obtained in the second exhibit features not fit for commercialization. / O objetivo do presente trabalho foi analisar o desenvolvimento da cultura da cravina em substrato de cinza de casca de arroz em diferentes tamanhos de vaso e sob variados níveis de disponibilidade hídrica, observando sua resposta quanto à altura das hastes desenvolvidas; número de nós por haste; peso fresco e peso seco das hastes e número de botões florais desenvolvidos por haste. A cultivar utilizada no experimento foi o híbrido interespecífico série Melody , sendo que as mudas foram obtidas por meio de estaquia de um matrizeiro implantado especificamente para tal objetivo. As mudas obtidas primeiramente foram plantadas em bandejas de enraizamento onde permaneceram por 30 dias, sendo após transplantadas em vasos plásticos pretos de 8 e 18 litros, preenchidos com substrato de cinza de casca de arroz, e mantidas em 100%, 80%, 60% e 40% do limite da capacidade de retenção hídrica dos vasos. A manutenção da umidade dos vasos foi realizada a partir do método de pesagens, sendo acrescentadas quantidades variáveis de água para manter o vaso no peso estipulado. O consumo de água das plantas também foi determinado através do método de pesagens, ao longo de dois ciclos de cultivo. Os resultados obtidos mostraram que o consumo hídrico dessa espécie é altamente influenciado pelas condições meteorológicas; recomenda-se o uso do vaso de menor capacidade e a manutenção da disponibilidade hídrica em 40% da capacidade de retenção de água; é preferível o cultivo da cravina em apenas um ciclo, já que as hastes obtidas no segundo apresentam características não próprias para a comercialização.