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1
Trømborg, Håkon. "Control system for the DNV GL Fuel Fighter Prototype and the DNV GL Fuel Fighter UrbanConcept." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for teknisk kybernetikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25969.
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In this report I present my work developing the main control unit in the two DNV GL Fuel Fighter cars that raced in Shell Eco-marathon 2014. The objective of the Shell Eco-marathon is to race a set distance using as little energy as possible, and my focus has been on giving the driver the tools and information to run the car in an energy efficient manner. I explored different existing driving strategies, and because of the high power consumption of the motor controller circuit I decided to use the "Pulse and Glide" strategy. This meant the car would accelerate rapidly to maximum speed and then coast with motor and its controller switched off.
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Tonning, Oluf Roar Bjørset. "Implementing Lean Systems Engineering in the DNV Fuel Fighter project." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produktutvikling og materialer, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18806.
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This thesis is a practical application of Systems Engineering in a full-scale project. The author has participated as a member of NTNU's Eco-marathon team, who has spent the last two semesters designing and manufacturing an energy-efficient car for the Shell Eco-marathon competition 2012. The author made an assessment of the project to find the areas where he should focus his effort. The author also applied Lean Thinking to find the Systems Engineering methods that would best aid the team improve within the areas uncovered in the assessment. The areas where the team needed improvement were Knowledge management and Continuous improvements of the product development process. By using Model-based Systems Engineering processes the author produced a system model acting as a knowledge repository. Then, the author used methods from Lean Thinking for knowledge capture, namely Knowledge Briefs and learning events.For improving the product development process, the author introduced the team to Visual Workflow Management to help the team become more agile, and to visualize project progress from multiple perspectives in order to discover parts of the system which is not evolving at the desired rate.Key concepts in this thesis include:Lean Thinking, Lean Systems Engineering, Model-based Systems Engineering, Model-based Documentation, Knowledge management, Knowledge briefs, A3 method, system modelling, functional analysis, functional flow block diagrams (FFBDs), system architecture, Visual Workflow Management, Stand-up meetings, Visual project board, risk management
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Bøvre, Mats, Marius Kyllo, Johannes Aalberg, Isak Olav Søbye Nordal, and Abal Lierni Imaz. "DNV GL Fuel Fighter : Development and Construction of Vehicles for Participation in Shell Eco- marathon 2014." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produktutvikling og materialer, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-26068.
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AbstractThis master thesis is the continuation of the 2013 autumn semester project report. The thesis seeks to describe the work done in order to participate with two vehicles in the European Shell Eco-marathon 2014 competition and to reach the result of:- 7th place in the Prototype battery electric category- 3rd place in the Urban Concept battery electric category A new prototype vehicle has been built to participate in a category which NTNU never has participated in before. This report includes the design and production of all the sub systems required to build and race the prototype vehicle. It also includes information about the work related to project management and promotion as well as the technical modifications which was done to improve the Urban Concept vehicle.
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Valen, Magnus. "Launch and recovery of ROV: Investigation of operational limit from DNV Recommended Practices and time domain simulations in SIMO." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11626.
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Offshore contractors seek to operate their remotely operated vehicles for the widest range of sea conditions where particularly launch and recovery through splash zone are critical phases in the offshore operation. The analytical methods for calculation of operational limit proposed by guidelines from DNV Recommended Practices may lead to an over-estimation of the hydrodynamic forces and consequently to an unduly restrictive operational limit. Accurate predictions of the hydrodynamic forces are important, and there is an opening in the regulations which allow the use of other analysis tools to determine the forces on the ROV system during launch and recovery. The main objective of the master thesis was to carry out splash zone analyses for DOF Subsea’s ROV system by use of DNV Recommended Practices and compare the results found by modeling the marine operation in the time domain simulation program SIMO. This involved a broad study of SIMO and a complete modeling of the offshore operation including calculation of the hydrodynamic data for the vessel Skandi Bergen and modeling of the ROV system. In SIMO, particularly the sea state of 4.5 [m] significant wave height was investigated since this is the current operational limit for DOF Subsea’s ROV system. The investigation of operational limits by use of the analytical method and SIMO have shown that DNV Recommended Practices over-estimates the hydrodynamic forces acting in the wave zone leading to an restrictive operational limit in comparison to the time domain calculations in SIMO. The calculations by the analytical method have shown that the operational limit for launch and recovery of ROV should be limited to 2.5 [m] significant wave height, while analyses in SIMO have shown that the current operational limit of 4.5 [m] could be justified. However, it is seen that the possibility for slack umbilical is present in the sea state of 4.5 [m] and peak periods in the range of Tp = 6 – 9 [s]. It is also to be noted that the slack umbilical occurrences show a thoroughly dependency of the vessel heading. Furthermore, the snap loads induced by the slack umbilical occurrences are not found to be critical in the irregular wave analyses. This can justify the operational limit of 4.5 [m] significant wave height as long as the weather is assessed by experienced personnel during deployment through wave zone and Skandi Bergen is positioned head sea.
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WAICHENBERG, LEONARDO LEMOS. "AN APPLICATION OF THE GAPS MODEL FOR THE IDENTIFICATION OF BRAND PERCEPTION OF A SERVICE COMPANY: THE DNV CASE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=16528@1.
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A presente dissertação teve como objetivo principal testar a aplicabilidade
do Modelo de Hiatos para identificar diferenças de percepção entre os clientes e
os gestores de uma empresa não orientada pelos princípios de marketing, em
relação à reputação de sua marca e de seus serviços. O trabalho apresenta a
empresa focal no detalhe e descreve os principais conceitos de marca, serviços e
marketing de serviços, além da relação entre eles. O método é baseado na
mensuração das percepções dos clientes da empresa em relação aos atributos de
sua marca e de seus serviços, as quais são contrastadas com as percepções de seus
gestores. Neste sentido duas pesquisas de campo são utilizadas, sendo uma de
natureza global e outra restrita aos clientes da empresa no Brasil. O foco principal
deste trabalho é a pesquisa local. Os resultados das duas pesquisas serviram de
base para apurar o nível de similaridade das percepções levantadas, segundo
mensuração feita com base em escalas quantitativas. O modelo de hiatos adotado
contribuiu para demonstrar que, apesar da boa reputação da empresa no tocante à
sua marca e aos serviços prestados, a percepção dos clientes estudados difere em
vários quesitos daquela imaginada pelos gestores da empresa. Este resultado
confirma a importância da pesquisa de mercado para o devido monitoramento da
marca e do nível de serviços de uma instituição. Objetivando minimizar essa
lacuna entre a percepção presumida e a obtida, são apresentadas algumas
sugestões para os praticantes e gestores, além de sugeridas novas pesquisas sobre
o tema.This dissertation`s main objective was to test the applicability of the Gaps Model to identify differences in perception between the clients and the managers of a company not driven by the marketing principles, in relation to the reputation of its brand and services. The paper presents the focal firm in detail and describes the main concepts of brand, service and marketing services and the relation between them. The method is based on the measurement of the customers’ perceptions related to the attributes of the company`s brand and services, which are contrasted with the perceptions of its managers. In this regard two field surveys are used, one being global and the other restricted to the firm’s clients in Brazil. The main focus of this work is the local research. The results of both surveys were the basis for determining the level of similarity of the raised perceptions, according to measurements based on quantitative scales. The adopted gaps model helped to demonstrate that, despite the company s good reputation in terms of its brand and the provided services, the researched customer`s perception differs in many areas on that envisioned by the enterprise’s managers. This result confirms the importance of market research for the proper monitoring of the brand and the services level of an institution. In order to minimize the gap between presumed and obtained perceptions, some suggestions are presented for practisers and managers, and further research on the topic also suggested.
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Vargas, Vivian Patricia Saldias. "Prevalência das fissuras labiopalatinas no município de Bauru: concordância de diagnóstico entre registros do HRAC/USP, DNV e SINASC." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/61/61132/tde-04032016-102118/.
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As fissuras labiopalatinas são as malformações mais comuns que atingem a face. Estudos epidemiológicos são importantes para o delineamento das ocorrências e alocação de recursos para tratamento. Objetivos: Determinar a prevalência das fissuras labiopalatinas no município de Bauru por sua notificação na Declaração de Nascido Vivo (DNV) e no Sistema de Informações sobre Nascidos Vivos (SINASC) e verificar a concordância de diagnóstico comparando com registros do Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de São Paulo (HRAC/USP). Metodologia: Estudo observacional retrospectivo por avaliação de todas as DNV e identificação dos indivíduos com fissuras labiopalatinas nascidos e domiciliados em Bauru entre 01/01/2000 e 31/12/2010, comparados aos dados cadastrais do HRAC/USP. A prevalência foi calculada pela divisão do número de crianças com fissuras labiopalatinas pelo total de nascidos vivos registrados no período. A notificação dos diferentes tipos de fissuras foi comparada pelo teste qui-quadrado. Resultados: No período de estudo foram avaliadas 50898 DNV, entre as quais havia 232 notificações de anomalias congênitas (1:219 nascidos vivos), sendo 25 de fissuras labiopalatinas (1:2036 nascidos vivos). No mesmo período foram registrados no HRAC/USP 77 casos, revelando uma prevalência de 1:661 nascidos vivos, representando 67,5% de subnotificação das fissuras. A fissura palatina foi a mais prevalente (34,9%), seguida pela fissura labiopalatina (31,7%) e pela fissura labial (30,2%), afetando predominantemente o gênero masculino (58,5%). A notificação da fissura palatina isolada (16,12%) foi menor comparada às fissuras labial (43,75%) e labiopalatina (54,54%). Conclusão: O estudo revelou predominância de fissura palatina, com expressiva subnotificação das fissuras no sistema público de saúde, de forma mais acentuada para as fissuras palatinas comparadas às fissuras labial e labiopalatina. Esforços devem ser realizados para tornar confiáveis e fidedignos os dados do sistema público de saúde que usa como fonte de dados as DNV e o SINASC.Cleft lip and palate are the most common congenital defects involving the face. Epidemiological studies are important for the delineation of cases and allocation of resources for treatment. Objectives: To determine the prevalence of cleft lip and palate in Bauru by notification in the Declaration of Live Birth (DNV) and Live Birth Information System (SINASC) as compared to records of the Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo (HRAC/USP). Methodology: Retrospective observational study by evaluation of all DNV and identification of individuals with cleft lip and palate born and living in Bauru between 01/01/2000 and 31/12/2010, compared to the registries of HRAC/USP. The prevalence was calculated by dividing the number of children with cleft lip and palate by the total number of live births recorded during the study period. Notification of different types of clefts was compared by the chi-square test. Results: During the study period 50,898 DNV were analyzed, among which there were 232 notifications of congenital anomalies (1:219 livebirths), being 25 of cleft lip and palate (1:2,036 livebirths). In the same period, the HRAC/USP registered 77 cases, revealing a prevalence of 1:661 livebirths, representing 67.5% of subnotification of clefts. Cleft palate was the most prevalent (34.9%), followed by cleft lip and palate (31.7%) and cleft lip (30.2%), predominantly affecting the male gender (58.5%). The notification of cleft palate (16.12%) was smaller compared to cleft lip (43.75%) and cleft lip and palate (54.54%). Conclusion: The study revealed predominance of cleft palate, with significant subnotification of clefts in the public health system, especially for cleft palate as compared to cleft lip and cleft lip and palate. Efforts should be made to achieve trustable and reliable data from the public health system that uses the DNV and the SINASC as data source.
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Yu, Hanqi. "Reliability Sensitivity Analysis of Dropped Objects Hitting on the Pipeline at Seabed." ScholarWorks@UNO, 2019. https://scholarworks.uno.edu/td/2710.
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Nowadays, as oil industry gradually moves towards deep sea fields with water depth more than 1000 meters, they are subjected to several threats which can cause failure of the pipeline, of which the accidentally-dropped objects have become the leading external risk factor for subsea developments. In this thesis, a sample field layout introduced in Det Norske Veritas (DNV) guide rules is selected as the study case with 100 m water depth. Six different groups of dropped objects are used in this paper. The conditional hit probability for long/flat shaped objects will be calculated with the methods from both DNV rules and an in-house tool Dropped Objects Simulator (DROBS). The difference between the results will be discussed. Meanwhile, the sensitivity analysis on mass, collision area , the volume, added mass coefficient and drag coefficient of the objects are calculated.
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Oskarsson, Daniel, and Jan-Erik Henriksson. "Modernisering av marint styr- och övervakningsskåp." Thesis, University West, Department of Technology, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-392.
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Yuguero, Garmendia Itxaso. "Development and construction of car for eco-marathon for participation in competition : Verification,Validation and Testing activities for the DNV Fuel Fighter 2." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produktutvikling og materialer, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18787.
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The goal of this Thesis is to verify a winning solution for the DNV Fuel Fighter 2, the verification of the design and development will be achieved by a series of verification, validation and testing activities.The Literature review of the report represents the VVT activities during the entire life cycle. The Theory and Methods used in the Thesis are based on A. Engel’s “Verification, Validation and Testing activities of Engineered Systems”. The author has customized those VVT activities so they fit the time and resource constrains of the case of study.The case is the NTNU’s fifth entrance to the Shell Eco Marathon competition, The DNV Fuel Fighter 2. The actual repot is a reflection of the first time in SEM’s project where an entire Thesis reflects the VVT activities in order to qualify the vehicle.This Master Thesis follows the work that was done in the specialization project 2011 fall in the NTNU. The fall report was focused on the trade-off and requirement analysis and in the definition a high level architecture that could be use in the project. The project work was used as a foundation for the work that was done afterwards in this Master Thesis. The work done during the year is based on the systems engineering effort made from the previous year. The author along with the other system engineer of the project has upgraded the SE effort.The main contribution of the Thesis has been the development of the VVT activities and to prove that they are useful for projects with time and resource constrains. The suggested future work consists of continuing with the use of the VVT strategy performed this year and to upgrade it until the Acceptance stage; where the final user will be the responsible of performing the tests.
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Salani, Marcelo Re [UNESP]. "Estudo das propriedades mecânicas de aços microligados produzidos por laminação controlada seguida de resfriamento acelerado para tubos API/DNV usado no projeto pré-sal." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/94378.
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Com os novos desafios impostos pelas condições cada vez mais severas dos poços de petróleo offshore a necessidade de materiais mais modernos e com melhores propriedades mecânicas tem sido um desafio constante. Neste trabalho foi realizada a caracterização mecânica de tubos fabricados a partir de chapas de aço laminadas a quente, seguido de resfriamento acelerado. Os valores reportados são resultados de testes de laboratório aplicados em corpos de prova retirados do metal de base, de solda e da zona termicamente afetada. A utilização destes aços na fabricação de tubos soldados por processo arco-submerso em dois passes, utilizando arcos múltiplos, tem apresentado resultados de tenacidades confiáveis e superiores aos obtidos a partir de chapas laminadas pelo processo de laminação controlada sem resfriamento acelerado, principalmente em espessuras de 16 mm e superiores. Os requisitos do teste de tenacidade especificados pela norma DNV-OS –F101 aplicados em tubos fabricados de acordo com a norma API 5L, são considerados críticos. A criticidade é função dos valores mínimos a serem obtidos e também da freqüência estabelecida para ser aplicada em cada corrida de aço utilizada na produção de cada item de fabricação. Com isso nota-se uma enorme vantagem do uso dos aços com o processo de resfriamento acelerado, visto que os mesmos tiveram uma melhor homogeneidade nos resultados de limite de escoamento, com um ganho significativo no alongamento e apenas uma pequena redução no limite de resistência. O fato de usarem menores teores de carbono, também favoreceu muito a tenacidade no metal de base e ao longo da ZTA, tendo diferenças extremamente significativas de ganho no teste de impacto e CTOD
The main of this work is the mechanical properties characterization of pipes made from steel plates produced using hot rolling with accelerated cooling. The values reported are laboratory tests results, applied on samples taken from the base metal, weld and heat affected zone. The use of these steel plates in the manufacture of pipes by submerged arc welding process using multiple arcs has shown toughness and elongation results superior to those obtained by using hot rolled steel plates without accelerated cooling, particularly in thicknesses of 16 mm and higher. The toughness test requirements specified by DNV-OS-F101 applied for pipes manufactured aiming offshore application are considered critical. The criticality is function of the minimum values required set the sampling frequency to be applied in every steel heat used in the production of each product. Because of this the use of accelerated cooling process shows a significant advantage, since it provides a better homogeneity in yield strength results, with a significant gain in elongation and only a small reduction in tensile strength. The use of smaller amounts of carbon also greatly fostered toughness in base metal and along HAZ, with significant improvement in the impact test and CTOD. Results due to these enhanced properties the use of steels with accelerated cooling technology is essential in order to face technological challenges imposed by new requirements of submarines pipelines
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Salani, Marcelo Re. "Estudo das propriedades mecânicas de aços microligados produzidos por laminação controlada seguida de resfriamento acelerado para tubos API/DNV usado no projeto pré-sal /." Guaratinguetá : [s.n.], 2011. http://hdl.handle.net/11449/94378.
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Orientador: Tomaz Manubu HashimotoBanca: Marcelo dos Santos Pereira
Banca: Cristina de Carvalho Ares Elisei
Resumo: Com os novos desafios impostos pelas condições cada vez mais severas dos poços de petróleo offshore a necessidade de materiais mais modernos e com melhores propriedades mecânicas tem sido um desafio constante. Neste trabalho foi realizada a caracterização mecânica de tubos fabricados a partir de chapas de aço laminadas a quente, seguido de resfriamento acelerado. Os valores reportados são resultados de testes de laboratório aplicados em corpos de prova retirados do metal de base, de solda e da zona termicamente afetada. A utilização destes aços na fabricação de tubos soldados por processo arco-submerso em dois passes, utilizando arcos múltiplos, tem apresentado resultados de tenacidades confiáveis e superiores aos obtidos a partir de chapas laminadas pelo processo de laminação controlada sem resfriamento acelerado, principalmente em espessuras de 16 mm e superiores. Os requisitos do teste de tenacidade especificados pela norma DNV-OS -F101 aplicados em tubos fabricados de acordo com a norma API 5L, são considerados críticos. A criticidade é função dos valores mínimos a serem obtidos e também da freqüência estabelecida para ser aplicada em cada corrida de aço utilizada na produção de cada item de fabricação. Com isso nota-se uma enorme vantagem do uso dos aços com o processo de resfriamento acelerado, visto que os mesmos tiveram uma melhor homogeneidade nos resultados de limite de escoamento, com um ganho significativo no alongamento e apenas uma pequena redução no limite de resistência. O fato de usarem menores teores de carbono, também favoreceu muito a tenacidade no metal de base e ao longo da ZTA, tendo diferenças extremamente significativas de ganho no teste de impacto e CTOD
Abstract: The main of this work is the mechanical properties characterization of pipes made from steel plates produced using hot rolling with accelerated cooling. The values reported are laboratory tests results, applied on samples taken from the base metal, weld and heat affected zone. The use of these steel plates in the manufacture of pipes by submerged arc welding process using multiple arcs has shown toughness and elongation results superior to those obtained by using hot rolled steel plates without accelerated cooling, particularly in thicknesses of 16 mm and higher. The toughness test requirements specified by DNV-OS-F101 applied for pipes manufactured aiming offshore application are considered critical. The criticality is function of the minimum values required set the sampling frequency to be applied in every steel heat used in the production of each product. Because of this the use of accelerated cooling process shows a significant advantage, since it provides a better homogeneity in yield strength results, with a significant gain in elongation and only a small reduction in tensile strength. The use of smaller amounts of carbon also greatly fostered toughness in base metal and along HAZ, with significant improvement in the impact test and CTOD. Results due to these enhanced properties the use of steels with accelerated cooling technology is essential in order to face technological challenges imposed by new requirements of submarines pipelines
Mestre
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Mohamed, Hassan Liban, and Haris Hodzic. "Modular and Flexible Payload Arrangement : With Reconfigurable Floors and Sliding Bulkheads." Thesis, Blekinge Tekniska Högskola, Institutionen för maskinteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-21854.
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Background The shipbuilding trends have changed from being single purpose ships only to using modular and flexible parts or systems to carry out multiple missions with as few ships as possible to minimize the ecological and economic impact. A flotilla can become smaller by having multiple ships capable of carrying out various missions instead of single-purpose ships. Objectives The objectives throughout the thesis are to provide an insight into how the trends today are affecting the market of surface ships and to study how a reconfigurable floor can be combined with a sliding bulkhead to be implemented into the cargo space. The developed concept needs to meet the regulations set by DNV-GL, which are an international classification society that is experts in risk management and quality assurance. This master’s thesis focuses on how to implement modularity and flexibility in payload arrangement for surface ships. Method The work process is based on the methodology design thinking’s four phases, which are initiation, inspiration, ideation, and implementation. Throughout the project, a trendwatching was conducted to determine the most impactful trends on the naval market. Using semi-structured interviews, techwatching and brainstorming iterations, a requirements list was defined to support the concept development. The concepts were weighed against each other, and the highest scoring was developed into a parametric CAD model. The model was later compared to the DNV-GL regulations to see whether the developed concept affects existing systems such as HVAC. Results Some of the top trends that have been affecting the naval market lately is modularity, flexibility, and unmanned surface vessels. The developed concept was a combination of a pallet loading floor and cargo floor rollers for reconfigurable floors and garage door-inspired bulkhead. The concept was visualized in Autodesk Inventor Professional 2020 to be further analyzed and display how the concept operates, its functions and how the system compares to DNV-GL regulations. Conclusions The top trends affecting the naval market are modularity, flexibility, and unmanned surface vessels to mention a few. Some of the regulations from DNV-GL that need to be considered when implementing a modular and flexible payload arrangement are fire protection and tightness requirements. However, the regulations can be stricter or changed depending on the role, design, and placement of the payload arrangement.
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Lundberg, Anders, and Tobias Jansson. "Preliminary study of a frame for a two module turbine system." Thesis, Linköpings universitet, Maskinkonstruktion, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72082.
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The development of steam turbines is continuously moving forward and the aim is oftento develop configurations with higher power output. Siemens Industrial Turbomachinery AB is currently in the beginning of a development project which replaces a single turbine with two interconnected turbines with higher pressure and temperature of the steam than before. To ensure reliable quality and hold down costs is it an advantage to do most of the assembly before delivery to site.This thesis work at Linköping University has been written in collaboration with Siemens Industrial Turbomachinery AB, Finspång. The objective of this work is to investigate the possibility to mount two turbines and a gearbox on a turbine frame. Theframe will be used both for transportation and during operation.The thesis considerate analyses of the turbine layout and critical parameters that may affect a turbine frame. In addition was a frame concept developed and evaluated with respect to solid mechanics and alignment of the shaft arrangement.Our conclusion is that there are good possibilities to install the equipment on a frame and achieve demands due to solid mechanics and alignment of the shaft arrangement.We recommend Siemens Industrial Turbomachinery AB to carry on with the project and do further investigations of the natural frequency of the frame concept, compare financial advantages and disadvantages together with possibilities for transportation.
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Jensen, Kim Rune. "Det norske Veritas og oljeutvinning til havs – gammel tradisjon i nytt farvann : Erfaringer med halvt nedsenkbare flytende plattformer og offshoreindustri 1968 – 1977." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for historie og klassiske fag, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21485.
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Med fremveksten av oljeutvinning til havs ble det behov for nye metoder for å lete etter olje, i tillegg til å hente den opp. Mobile plattformer ble til i tiden rundt 1950 som et resultat av oljeindustriens vekst, og klasseselskapene gikk aktivt inn for å involvere seg i klassifisering av disse plattformene. Etter kort tid kom problemstillingen om hva en mobil plattform var – et skip eller noe annet? Det norske Veritas involverte seg i den begynnende olje- og gassutvinningen i Nordsjøen ganske tidlig. For selskapet var offshoreindustri et skritt vekk fra det tradisjonelle klassearbeidet. Likevel åpnet industrien flere dører for klasseselskapet, samtidig som det bød på nye utfordringer. Mobile plattformer var noe nytt, men hadde samtidig en forankring i det maritime miljøet. Det norske Veritas prøvde slik å utnytte sin egen lange erfaring fra skip, ved å overføre den til et eget regelverk og en egen klasse for mobile plattformer. Selskapet kjempet slik for å få en kontrollordning på mobile plattformer basert på samme ordning som for skip. Sjøfartsdirektoratet hadde et langt og nært samarbeid med Det norske Veritas. Med opprettelsen av Oljedirektoratet ble klasseselskapet en årsak til uenighet innad i direktoratene, og da spesielt omkring arbeidet med mobile plattformer - en uenighet som ville følge alle aktørene gjennom hele perioden. Spørsmålet om hva en mobil plattform skulle defineres som var også medvirkende. Oppgaven avslutter med rammeavtalen mellom Det norske Veritas og Oljedirektoratet i 1977.
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Karlsson, Lars, and Andreas Köhler. "Dimensionering av bladförband på Kamewa CPP (Controllable Pitch Propeller)." Thesis, Karlstad University, Karlstad University, Karlstad University, Division for Engineering Sciences, Physics and Mathematics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-3332.
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The thesis project is accomplished during winter and spring 2008 at Karlstad University at the faculty of technology and science. The tutor at Karlstad University is Nils Hallbäck and the examiner is Hans Johansson. Rolls-Royce at Kristinehamn in Sweden is the initiator for the project. The thesis project title is design of the blade bolt joint on Kamewa CPP. CPP stands for controllable pitch propeller. The study include two main aspects which are to analyze if the blade bolt joint which is used today can be applied on a larger propeller and if there are better solutions or other possibilities to join the blade to the hub. First the classification rules of some institutes were studied to find out which limitations there are. Bolted joint has to exceed a minimum bending strength and the bolts have to be made out of steel and their strength has to be at least 10.9. Today Rolls-Royce use ten bolts per propeller, five on each side of the blade. To analyze the strength of the blade bolt joint connection a FEM and an analytic analyze were made and the results compared with each other. Two cases were examined, one for drift and two when hitting an iceberg. The results were similar to each other for FEM and the analytic analyze. At drift all bolts were under the tensile strength of 750 MPa but when using ice loads some bolts started to deform. A new concept for the bolt connection was tested. Again the stress in the bolts stayed under the tensile strength at drift but deformed when applying ice loads. A difference between analytical and FEM analysis was that the stress difference between the bolts were minor in the FEM method. Another concept was only studied with FEM and it had a geometric locking devise combined with the same blade bolt connection as Rolls-Royce use today. At drift the locking devise didn’t support the connection much but when applying ice loads less bolts started to deform and less material in the bolts reached the tensile limit. All three concepts showed stress concentrations at the first two or three threads. The differences between the three concepts weren’t that large and to get better results other possibilities have to be considered. It is important to know how much torque has to be applied on the screw to get the right amount of pretension. Three aspects to consider are to apply the torque without getting any torsion in the screw, to lower the moment with the right coating or lubricant and to avoid the stress concentrations at the threads. Superbolts and clampnuts are two possibilities to avoid torsion in the screws. By using screw thread inserts or tension optimized threads the stress in the thread gets optimized and a coating or lubricant with a low friction coefficient will lower the torque. Three possible solutions are suggested.
Examensarbetet har utförts på fakulteten för teknik och naturvetenskap under vintern och våren 2008 och är en kurs på 22,5 hp med kurskoden MSGC 17. Handledare på Karlstads universitet är Nils Hallbäck och examinator är Hans Johansson. Rolls-Royce i Kristinehamn är uppdragsgivaren till examensarbetet. Uppgiften är att dimensionera ett bladförband till en stor Kamewa Ulstein CP-propeller. Frågeställningen som ska besvaras är om det går att använda dagens förband och undersöka om det finns bättre alternativ eller andra lösningar på problemet. Det finns inga ritningar på den storleken av propellrar som förbandet ska göras till. Därför måste man skala upp mått från mindre propellrar. Propellerdiameter är 7,7 meter och bladet med fot väger 10 ton efter skalningen. Förbandet ska klara av DNVs (Det Norske Veritas) klassificeringskrav för böjmotstånd och förbandet dimensioneras därefter. För dagens förband behövs det mycket stora skruvar för att klara klassificeringskravet. En analytisk och en FEM-analys genomfördes för att det inte finns något material att jämföra med. Krafter som måste betraktas är centrifugalkraften, tyngdkraften, framdrivningskraften från vattnet samt en isbelastning vid kollision med ett isberg. Framdrivningskraften varierar med 20 % när propellern passerar skrovet. Resultaten från analyserna gav att dagens förband klarar belastningarna vid drift, dock att bultarna börjar deformeras vid belastning med iskraften. I den analytiska analysen antar man att alla delar (bladfot, fläns och nav) är stela och inte deformeras. Dessutom tar man inte hänsyn till böjpåkänningarna som uppstår i skruvarna. Detta tas med i FEM-analysen samt att man räknar med olinjära materialsamband. Därför uppstår det stora spänningsskillnader, upp till 210 MPa, i bultarna vid FEM-analysen vilket inte sker vid de analytiska beräkningarna. Ett antal koncept genererades och två av dessa analyserades närmare. Båda koncepten är optimerade för centrifugalkraften eftersom den utgör den största belastningen under drift om man bortser ifrån förspänningen. Koncept 1 är ett förband som består av 16 bultar per propeller med tre olika storlekar. Enligt FEM analysen fås en jämnare spänningsfördelning över skruvarna än med dagens förband, medan den analytiska metoden ger ungefär samma fördelning som vid dagens förband. Alla skruvar håller sig under sträckgränsen vid drift. Vid isbelastningen uppnås sträckgränsen i många av de mindre skruvarna och skruvarna börjar deformeras plastiskt. I detta avseende stämmer den analytiska lösningen och FEM-analysen överens. Skillnaden är att den analytiska beräkningen visar större spänningsvariation bland skruvarna dvs. att den största och minsta spänningen hos bultarna är högre än vid FEM-beräkningarna. Det andra konceptet som analyserades närmare består av en formlåsning som sitter under bladet tillsammans med samma skruvar som används vid dagens förband. Vid drift märks knappt någon skillnad. Vid isbelastningen så tar formlåsningen dock upp mer spänning och avlastar skruvarna. Färre skruvar deformeras plastiskt. Det finns möjligheter att använda sig av redan befintliga lösningar som Superbolts, clampnuts och andra verktyg. Det som är avgörande för förbandets funktion är ett korrekt åtdragningsmoment. Positivt är att samtidigt kunna förspänna skruvarna utan torsion. En lösning är att ytbehandla skruvarna med en beläggning med känd friktionskoefficient.
Tre lösningsförslag har tagits fram som ger ett bättre resultat än dagens förband.
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Floridia, Daniele. "Hybrid foundations for offshore wind turbines." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amslaurea.unibo.it/3284/.
Full textAbstract:
Nowadays offshore wind turbines represents a valid answer for energy production but with an increasing in costs mainly due to foundation technology required. Hybrid foundations composed by suction caissons over which is welded a tower supporting the nacelle and the blades allows a strong costs reduction. Here a monopod configuration is studied in a sandy soil in a 10 m water depth. Bearing capacity, sliding resistance and pull-out resistance are evaluated. In a second part the installation process occurring in four steps is analysed. considering also the effect of stress enhancement due to frictional forces opposing to penetration growing at skirt sides both inside and outside. In a three dimensional finite element model using Straus7 the soil non-linearity is considered in an approximate way through an iterative procedure using the Yokota empirical decay curves.
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Steven, Adelina. "Risk Assessment of Dropped Cylindrical Objects in Offshore Operations." ScholarWorks@UNO, 2018. https://scholarworks.uno.edu/td/2495.
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Dropped object are defined as any object that fall under its own weight from a previously static position or fell due to an applied force from equipment or a moving object. It is among the top ten causes of injuries and fatality in oil and gas industry. To solve this problem, several in-house tools and guidelines is developed over time to assess the risk of dropped objects on the sub-sea structures. This thesis focuses on compiling and comparing those methods in hope to improve the recommended practices available in the market. A simple modification is done on the in-house tools to better predict the landing point distribution of the dropped cylindrical objects on the seabed by imposing the random three-dimensional rotation around the water depth axis. This tool is then used to compare the result of annual hit frequency using the recommended practice and further compared with the available experimental data.
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Clements, Andrea D., C. Richard Parker, Wallace E. Jr Dixon, and Brenda Salley. "Marshmallows Used as Saliva Stimulant Do Not Affect Cortisol Concentrations: Finally a Palatable Alternative for Toddler Saliva Collection." Digital Commons @ East Tennessee State University, 2007. https://doi.org/10.1002/dev.20238.
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Two studies were conducted to validate marshmallows as a saliva stimulant for use with toddlers. First, cortisol concentrations from 14 subjects (ages 6–46 years) were compared using three saliva collection methods: (1) plain cotton dental roll, (2) dental roll with one mini-marshmallow, and (3) expectorating into a collection tube using no cotton or stimulant. EIA was used for analyses. There were no significant differences among cortisol concentrations. Second, saliva collection compliance rate was compared for 21-month-olds (n = 51) using either flavored drink crystal- (compliance rate = 16.7%) or marshmallow-flavored (compliance rate = 60%) dental rolls for saliva collection (χ2 )1) = 4.02, p = .045). These studies indicate that marshmallow is a viable option for saliva stimulation to determine toddler cortisol concentrations using EIA.
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Clements, Andrea D. "Cortisol Measurement in Developmental Research: Where Do We Go From Here?" Digital Commons @ East Tennessee State University, 2013. https://doi.org/10.1002/dev.21025.
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Salivary cortisol has been measured extensively in developmental research over the last three decades. The purpose of this article is to summarize the contributions to and limitations of salivary cortisol measurement in developmental research and propose future directions for research that includes salivary cortisol measurement. The properties of cortisol, the history of its burgeoning popularity, and the utility and limitations of (a) cortisol as a biological indicator, (b) saliva as a source of cortisol, and (c) various saliva collection methodologies are described. The current state of understanding about what is and is not reliably predictable from cortisol is summarized and the value of salivary cortisol measurement in developmental research is discussed, addressing whether methodology could be driving research design. Recommendations are made for streamlining study design and reporting within developmental research.
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Davis, Molly, Kara West, Joanie Bilms, Diana Morelen, and Cynthia Suveg. "A Systematic Review of Parent-Child Synchrony: It’s More Than Skin Deep." Digital Commons @ East Tennessee State University, 2018. https://doi.org/10.1002/dev.21743.
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This manuscript provides a critical review of the literature on parent–child physiological synchrony—the matching of biological states between parents and children. All eligible studies found some evidence of physiological synchrony, though the magnitude and direction of synchrony varied according to methodological factors, including the physiological system examined (i.e., parasympathetic or sympathetic nervous system activity, adrenocortical functioning) and the statistical approach used (e.g., multilevel modeling, correlation). The review underscores the need to consider the context in which physiological synchrony occurs (e.g., family risk) to best understand its significance. Furthermore, the review delineates vital avenues for future research, including the need to assess synchrony across multiple physiological systems and the importance of documenting continuity/change in physiological synchrony across developmental periods. Such research is crucial for understanding how the parent–child relationship unfolds at a physiological level and, in turn, how this relationship can facilitate or hinder parent, child, and family adjustment.
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Stacevičius, Domas. "Genominės DNR metilinti regionai." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080407_105619-10194.
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Darbo tikslas: Apžvelgti ir apibendrinti ankstesnius tyrimus apie genominės DNR metilinimą bei šio biocheminio proceso svarbą gyvam organizmui. Darbo uždaviniai: Išanalizuoti ir apibendrinti esamą mokslinę literatūrą apie:1. DNR metilinimo bazinius aspektus. 2. DNR metilinimo procesų eigą. 3. DNR metilinimo biologinę esmę ir reikšmę. 4. DNR metilinimo procesus eukariotuose ir prokariotuose. 5. DNR metilinimo tyrimo metodus. 6. DNR metilinimo duomenų bazes. Darbas paremtas įvairių autorių anksčiau publikuotais duomenimis apie DNR metilinimą ir jo biologinę reikšmę. Surinkta, išnagrinėta ir apibendrinta literatūra apie DNR metilinimą leidžia geriau suprasti ir papildyti žinias apie DNR metilinimo reikšmę ląstelių diferenciacijai, apsaugai, genų represijai ir indukcijai, nukleotidų pasikeitimui genome bei organizmų evoliucijai. Išvados: 1. Metilinimas yra svarbi DNR modifikacija., nuo kurios priklauso svarbūs genetiniai reiškiniai – genomo imprintingas ir apsauga, chromatino sandara, ląstelės ciklo ir genų veiklos valdymas. Metilinimo procesas labai svarbus embriogenezės ir organizmo vystymosi metu, nes nuo jo priklauso genų ekspresija. 2. Citozino likučių metilinimas katalizuojamas fermentais - DNR metiltransferazėmis, kurie randami prokariotuose ir eukariotuose. 3. Metilinimas atlieka ir kitas funkcijas: dalyvauja replikacijos tikslumo kontrolėje, de novo metilinime, taip pat demetilinimo procesuose.To view and generalize previous analysis about genomic DNA methylation and stress out of this biochemical process to the alive organism. Fit up, analyse and generalize scientific literature about: DNR methylation fundamental dimensions, DNR methylation process, DNR methylation biological point and consideration, DNR methylation process in eukariotics and prokaryotics, DNR methylation exploratory methods, DNR methylation databases. Methylation is an essential DNA modification, whose over depend important genetic expressions – genomic inprinting and conservancy, chromatin structure, cell cycle and repression of genes activity. Methylation process is very important during embryogenesis and organism evolution, because its over depend gene expression. There are three DNA methylation conditions: non-methylated site, methylated site and hemi-methylated site. Methylation investigation was navigate in germ. Parent methylation function in germ is a mechanism, which protects a cell from extraneous DNA institution.
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Henning, Anja. "Einsatz von einzelsträngigen DNS-Templaten zur Erstellung funktioneller DNS-Nanostrukturen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-112695.
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Der Grundbaustein des Lebens, die Desoxyribonukleinsäure (DNS), ist aufgrund ihrer spezifischen Basenpaarung ein geeignetes Molekül, um stabile und vielfältige nano- beziehungsweise mikrometergroße Strukturen herzustellen. Diese selbstorganisierten DNS-Strukturen eignen sich als Grundeinheiten für die Ausrichtung anorganischer und organischer Materialien. Für die Synthese solcher DNS-Strukturen werden insbesondere die Kachel-basierte Assemblierung (engl. tile-based assembly, im Folgenden als Tile-basierte Assemblierung bezeichnet) oder die DNS-Origami-Methode verwendet. Die Tile-basierte Assemblierung beinhaltet die Verbindung einzelner DNS-Bausteine, den sogenannten Kacheln (engl. tiles), zu komplexeren DNS-Strukturen. Hingegen entspricht die DNS-Origami-Methode der Faltung eines langen einzelsträngigen DNS-Moleküls, dem sogenannten scaffold, anhand von hunderten kurzen Oligonukleotiden (Heftklammer-Oligomeren, engl. staple strands) hin zu einer entsprechenden Form.
Hinsichtlich einer zukünftigen Erstellung von DNS-basierten, nanoelektronischen Systemen war das Ziel dieser Arbeit einheitliche zwei- (2D) und dreidimensionale (3D) DNS-Nanostrukturen herzustellen, Methoden für deren kontrollierte Vernetzung zu entwickeln sowie deren chemische Funktionalisierung mit Nanomaterialien und einer beispielhaften Integration in lithographisch gefertigten Mikrokontaktstrukturen durchzuführen. Hierfür war es notwendig, einen weiten Bogen zu spannen, welcher einerseits verschiedene Konstruktionsprinzipien der DNS-Nanotechnologie vorteilhaft miteinander vereint und der andererseits die weitreichenden Möglichkeiten der chemischen Funktionalisierung der sogenannten DNS-Templatstrukturen auslotet.
Konkret wurden zur Erstellung von einheitlichen DNS-Strukturen Assemblierungskonzepte verwendet bzw. entwickelt, welche auf die Ausrichtung einzelner kurzer Oligonukleotide anhand eines langen einzelsträngigen DNS-Templates beruhen. Im ersten Teil der Arbeit ist anhand eines selbstkomplementären Einzelstranges aufgezeigt, wie sich prinzipiell die Wachstumsrichtung einer Tile-basierten Struktur durch die Verwendung eines einzelsträngigen DNS-Templates beeinflussen lässt. Bei diesem Ansatz bildet sich entlang des DNS-Templates eine 2D-Gitterstruktur aus einheitlichen und abschnittsweise selbstkomplementären hexagonalen oder tetragonalen Oligonukleotideinheiten aus. Diese gerichtete Selbstassemblierung führt schließlich zum Aufrollen und Zusammenschluss der 2D-DNS-Struktur zu einer tubulären Struktur. Die Größe und Geometrie der Oligonukleotideinheiten bestimmen dabei maßgeblich den Durchmesser dieser DNS-Nanoröhren. Zur Erklärung von experimentellen Beobachtungen wurde ein Modell entwickelt, welches die Templat-gestützte Assemblierung theoretisch beschreibt. Die erstellten, strukturellen Anforderungen genügenden Nanoröhren eignen sich für eine gleichmäßige Funktionalisierung mit Nanomaterialien, wie anhand der Ausrichtung von Gold-Nanopartikeln gezeigt wurde.
In einem weiteren Teil der Arbeit wurde eine ca. 400 nm lange DNS-Nanoröhre anhand der DNS-Origami-Methode erstellt. Diese Nanoröhre diente als Modellsystem zur Untersuchung der Integration von tubulären DNS-Strukturen in Mikrokontaktstrukturen mittels der Dielektrophorese. Eine positive dielektrophoretische Antwort der 3D-DNS-Strukturen konnte im MHz-Bereich festgestellt werden. Des Weiteren wurde für mit Gold-Nanopartikeln funktionalisierte DNS-Nanoröhren eine verstärkte dielektrophoretisch Antwort beobachtet. Neben der Manipulation bzw. Ausrichtung von DNS-Nanostrukturen wurden Konzepte entwickelt, welche zusätzlich zum Aufbau komplexer DNS-Netzwerke innerhalb einer Mikrokontaktstruktur erforderlich sind. Konkret konnte eine Verbindung der 3D-Nanoröhren (i) untereinander über eine 200 nm lange kreuzartige DNS-Zwischenstruktur und (ii) endständig mit einer Goldoberfläche ermöglicht werden.
Der dritte Teil dieser Arbeit befasste sich mit der Entwicklung einer modularen 2D-DNS-Struktur, welche unter anderem für eine vergleichbare Untersuchung zur Immobilisierung von Nanomaterialien auf DNS-Strukturen dienen kann. Anhand der DNS-Origami-Methode wurde eine spezifische DNS-Gerüststruktur entworfen, welche die Ausstattung mit einer funktionalisierbaren Tile-basierten Einheit erlaubt. Um die Modularität der DNS-Gerüststruktur zu verdeutlichen, wurden zwei unterschiedliche, drei-beinige Tiles entworfen und anhand eines Ein- oder Zwei-Schritt-Verfahrens in die DNS-Gerüststruktur integriert. Die Anbindung eines Gold-Nanopartikels an jedes Bein des eingebundenen Tiles demonstriert die spezifische Funktionialisierbarkeit dieses Modellsystems. Zudem wurden Methoden, welche zur Aufreinigung der funktionalisierten DNS-Gerüststrukturen dienen, wie auch Effekte der Vernetzung von DNS-Origami-Strukturen anhand unspezifischer Wechselwirkungen untersucht.
Die Ermittlung der Struktureigenschaften beziehungsweise der Assemblierungsqualität der in dieser Arbeit gezeigten DNS-Strukturen erfolgte mittels elektrophoretischer und bildgebender Untersuchungsverfahren (Rasterkraftmikroskopie, Transmissionselektronenmikroskopie, Rasterelektronenmikroskopie).
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Gedgaudaitė, Aušra. "Paukščių muziejinės medžiagos panaudojimas genetiniams tyrimams." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080628_090602-96528.
Full textAbstract:
Šio darbo tikslas buvo įvertinti T. Ivanausko zoologijos muziejuje surinktą vištinių paukščių medžiagą ir išanalizuoti jos tinkamumą genetiniams tyrimams atlikti. Pagrindiniai darbo uždaviniai buvo nustatyti T. Ivanausko muziejaus vištinių paukščių eksponatų rūšinę sudėtį ir pagrindines radimvietes, išskirti DNR iš muziejinės ir šviežios medžiagos ir atlikti mikrosatelitinę ir AAPD analizę. Panaudojant Laird ir kt. 1991 metodiką su kai kuriomis modifikacijomis iš šviežios medžiagos, muziejinių plunksnų ir odos buvo išskirta DNR. Iš muziejinių plunksnų ir odos išsiskyrusi DNR yra fragmentuota, todėl netinkama AAPD analizei. Gali būti, jog neigiamą poveikį eksponatų DNR turi arsenas, kuris naudojamas kaip konservanatas paruošiant odas, ar netinkamos eksponatų laikymo salygos. Iš šaldytų, šviežiai išpeštų plunksnų ir spirite fiksuotų audinių išsiskyrusi DNR yra nefragmentuota ir yra tinkama AAPD analizei atlikti. Naudojant 3 pradmenis: ROTH 180-04, OPA04 ir OPA11, AAPD metodu buvo išanalizuotos 3 naminių vištų imtys (iš Suvalkų krašto ūkio ir Žemaitijos ūkio paimtos hibridinių vištų imtys ir LVA rodailendų veislės vištų imtis). Visos hibridinės vištos buvo fenetiškai panašios į rodailendų veislės vištas. Pagal visus tris pradmenis bendras lokusų skaičius buvo 42, iš kurių 32 buvo polimorfiniai Suvalkų krašto ūkio vištose, 14 polimorfinių Žemaitijos ūkio vištose. Visi LVA vištų lokusai buvo monomorfiniai. Iš filogenetinio medžio nustatyta, kad LVA vištos genetiškai buvo... [toliau žr. visą tekstą]The aim of this study was to collect information about T.Ivanauskas zoo museum Galliformes and to evaluate the application of Galliformes museum piece for genetic analysis. The main tasks were to estimate the composition of species and the main finding places of Galliformes, to isolate DNA from museum feathers or skins and newly plucked feathers and to perform microsatellite or RAPD analysis. DNA from museum feathers and skins was fragmented and unsuitable for RAPD analysis. Museum specimens were salted with arsenic and it is known that arsenic inhibits DNA reparation. So, it might lead that arsenic or nonsuitable storage conditions might compromiseability to amplify DNA with PCR, further studies are needed to confirm this. DNA from newly plucked feathers and ethanol fixed tissues was suitable for RAPD analysis. Using RAPD method with 3 primers: ROTH 180-04, OPA04 ir OPA11 we evaluated 3 groups of chicken: 2 crossbred groups from Suvalkai farm and Zemaitija farm and group from LVA pedigree chickens. It was etimated 42 loci, 32 of them were polymorphic in the chicken group from Suvalkai farm, 14 polymorphic in the chickens from Zemaitija farm. All loci of LVA chickens were monomorphic and these chickens were genetically identic. The group of chickens from Zemaitija farm were more similar to LVA chickens than the group of chickens from Suvalkai farm. Using RAPD method ROTH 180-04, OPA04 ir OPA11 primers availability for other Galliformes (Tetrao tetrix and Tetrao urogallus)... [to full text]
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Plankytė, Jurga. "Kriminalistinis žmogaus plaukų tyrimas:galimybės ir praktika Lietuvoje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2007~D_20080125_103700-54383.
Full textAbstract:
Žmogaus plaukas – neatsiejama žmogaus organizmo dalis. Lietuvos kriminalistikos moksle plaukas priskiriamas biologinių objektų grupei, o tiriant įvairius nusikaltimus, neretai tampa puikiu informacijos šaltiniu.
Baigiamajame darbe pateikiama trumpa kriminalistinio žmogaus plaukų tyrimo istorinė raida Lietuvos prieškario ir pokario laikotarpiu.
Trumpai yra aprašoma žmogaus plauko struktūra.
Pateikiami trys pagrindiniai kriminalistiniai plaukų tyrimo metodai: morfologinis, serologinis ir DNR analizės. Aptariamos šių metodų atlikimo galimybės Lietuvoje.Palyginimui pateikiamos naujausios žmogaus plaukų tyrimo metodikos užsienio šalyse (Anglijoje, Vokietijoje, Švedijoje) – žmogaus plauko kutikulės išliejos metodas; botaninės kilmės aplinkos dalelių (žiedadulkių ir sporų) žmogaus plaukų nuoplovose metodas; katageninių ir telogeninių plaukų DNR tyrimai, pasitelkus „LCN sistemą“; geno (MC1R), apsprendžiančio žmogaus plaukų spalvą ir odos tipą, mutacijų tyrimas; narkotinių medžiagų žmogaus galvos ir gaktos plaukuose nustatymo tyrimai.
Analizuojama Lietuvos ekspertinių įstaigų 2004-2006 metų veikla, susijusi su kriminalistiniu žmogaus plaukų tyrimu.
Aptariami ekspertų-specialistų anketinės apklausos rezultatai.
Pateikiama išsami ekspertizės aktų analizė, statistiniai duomenys apie nusikaltimus, kurių aplinkybėms aiškinti buvo tiriami žmogaus plaukai, įrodoma žmogaus plaukų, kaip tyrimo objekto kriminalistikoje, reikšmė, tiriant smurtinius ir... [toliau žr. visą tekstą]Human hair – a part of human body. Lithuanian Forensic Science it presents like the group of biological evidences. Due investigation of the variuos commited crimes, human hair becomes a wide source of important and useful informacion. Noted a short Lithuanian prewar and postwar history of forensic human hair exploration. Shortly described a structure of human hair. There were mentioned three, the main ways of forensic investigation of human hair in Lithuania: morphological, serological exploration and DNA analysis. The procedures and the opportunities of these methods applied in Lithuania, were discussed as well. Described the modern procedures of human hair investigation: a scale cast obtained from shaft of human hair; the exploration of polynomorphs (pollens and spores) in human hair; the DNA analysis of human catagen and telogen hair by Low Copy Number (LCN) method; a single gene (MC1R) extraction for identification of human hair colors from degraded DNR; the human hair analysis for drugs detection in it. Submited a comprehensive assay of activity in Lithuanian Forensic Institutes, which is dealing with forensic human hair investigation. There was offered an importance of human hair exploration in forensic trial. Equally, were presented an inquiry results of Lithuanian forensic experts. Were discussed a generalization of forensic experts reports, shown a statistic of commited crimes, where the human hair was found and took like... [to full text]
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Buchovska, Jurata. "Geographical distribution patterns of DNA polymorphism of scots pine (Pinus Sylvestris L.) at the eastern part of the species range." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2013~D_20131218_133551-78973.
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In Lithuania, it is a first genetic study that analyses the DNA polymorphism of Scots pine at the level of cell’s nucleus and organelle’s genomes. In Europe, it is one of the first studies of DNR-based population structure covering in detail the eastern range of Scots pine, where the populations originate from Scotland in the west up to the Amur river estuary in the east. Our material represents a great magnitude of adaptive environments including the core populations at the central part of the species range as well as the marginal populations. The analysis was performed using high resolution and repeatability microsatellite DNA markers.Tai yra pirmas genetinis mokslinis darbas Lietuvoje, nagrinėjantis paprastosios pušies DNR polimorfizmą ląstelės branduolio ir organoidų genomų lygmenyse. Europoje tai vienas iš pirmųjų mokslinių darbų, detaliai analizuojantis DNR polimorfizmą rytinėje paprastosios pušies rūšies arealo dalyje. Darbe lyginamos populiacijos, pradedant Škotija vakaruose, baigiant Amūro upės žiotimis tolimuose rytuose. Taip reprezentuojamas visas adaptacinių aplinkų gradientas: Europa–Uralas–Tolimieji Rytai. Tyrimui naudoti aukštos genetinės rezoliucijos ir patikimo pakartojamumo mikrosatelitinės DNR žymenys.
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Becker, Nils B. "Sequence dependent elasticity of DNA." Doctoral thesis, [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1186511923001-71752.
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Seidel, Ralf. "Methods for the development of a DNA based nanoelectronics." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2003. http://nbn-resolving.de/urn:nbn:de:swb:14-1074596565484-95599.
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The exceptional self-assembly properties of DNA as well as its ability to interact with different kinds of chemical compounds and biological structures make this biomolecule to an interesting object for the fabrication of artificial nanostructures. In this work several methods for a DNA-based self-assembly of electronic nanocircuitry are explored. For this, four basic steps, which turned out to be essential within a circuit assembly process, are addressed: (i) The formation of multi-branched DNA junctions by a simple building-block procedure. (ii) The site-specific attachment of nanoobjects (gold colloids) at the center of DNA junctions. (iii) The integration of DNA into microstructured gold electrode arrays, in particular the stretching of single DNA molecules between two electrodes. For this a simple, but reliable methods for the functionalization of gold electrodes by using aminoethanethiol was developed, which enables end-specific attachment of the DNA but does not require DNA modification. (iv) The metallization of DNA. A synthesis procedure was developed, which results in the formation of continuous chains of 5nm platinum clusters along the DNA. The metal deposition process turned out to take place exclusively at the DNA while background metallization is completely suppressed.
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Dinu, Cerasela Zoica. "Leveraging the motor protein Kinesin to manipulate DNA molecules in synthetic environment." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2006. http://nbn-resolving.de/urn:nbn:de:swb:14-1149612769067-28113.
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Die vorliegende Doktorarbeit stammt aus (ist in) dem Bereich der NanoBioTechnologie. Ihr Ziel ist es, das Motorprotein Kinesin und Mikrotubuli einzusetzen, um DNS-Moleküle in einem synthetischen Umgebung zu manipulieren. Diese Doktorarbeit setzt sich aus fünf Kapiteln zusammen. In der Einführung wird die makromolekulare Struktur der Zelle beschrieben, z.B. das Zytoskelett und Kinesin, eins der Motorproteine, die auf Mikrotubuli entlang laufen können. Der Schwerpunkt dieses Kapitels liegt auf der Nützlichkeit biologischer Motoren für den Aufbau und die Organisation von Strukturen im technischen Umfeld. Das zweite Kapitel zeigt, wie Kinesin und Mikrotubulis in einem synthetischen Umfeld für den Transport verschiedener Frachten, z.B. Streptavidin, Quantum dots oder DNS-Molekülen, genutzt werden können. Hier liegt der Schwerpunkt auf der Manipulation der DNS-Moleküle durch motor-gesteuerte Mikrotubulis und wie dieser Fracht-Transport-Mechanismus prinzipiell als Basis für die Entwicklung neuer Konzepte im Bereich des Bioingenieurwesens dienen kann. Ein Beispiel für ein solches Konzept ist die auf DNS basierende Molekularelektronik, bei der die Bindung und Streckung von DNS-Molekülen zwischen leitfähigen Oberflächen notwendig ist. Das dritte Kapitel beschreibt den Einfluß der Oberflächeneigenschaften auf die DNS-Anbindung. Es bietet Antworten darauf, wie diese Eigenschaften erforscht, spezifisch gestaltet und vorbereitet werden können, so daß sie der wissenschaftlichen Zielsetzung angemessen sind. Auf die Betrachtung von komplexen Musteranordnungen, wie sie in der Nanoelektronik genutzt werden können, wird im vierten Kapitel eingegangen. Hier wird auf praktische Art und Weise deutlich gemacht, wie DNS-Moleküle an leitfähige Oberflächen gebunden und dort durch Motorproteine und Mikrotubulis manipuliert werden können. Die Vorteile der motor-basierten Manipulation gegenüber den konventionellen Methoden wie AFM oder der optischen Pinzette werden diskutiert. Das fünfte und letzte Kapitel zeigt, wie man das Kinesin-Mikrotubuli-System nutzen kann, um daraus Informationen über DNS-Moleküle abzuleiten. Dafür wurde das Verhalten der Mikrotubulis in Beziehung auf die von gebundenen DNS-Molekülen ausgeübten Kräfte untersucht. Zusammenfassend habe ich experimentelle Untersuchungen und Färbeprotokolle entwickelt, um den gesamten Manipulationsprozeß zu detektieren, visualisieren und kontrollieren. Weiterhin untersuchte ich seine Implikationen auf theoretische Analysen, sowie auf praktische Anwendungen im Nano-Ingenieurwesen. Meine Daten demonstrieren, das DNS-Moleküle im synthetischen Umfeld so manipuliert werden können, daß kontrollierte DNS-Bioschnittstellen entstehen; Schnittstellen, die sowohl für weitere nanoelektronische Anwendungen als auch für topologische DNS-Studien genutzt werden können. Es wird weiterhin erwartet, daß das Kinesin-Mikrotubuli-System für die 3D-Anordnung auf biomolekularer Ebene im technischen Umfeld eine ebenso wichtige Rolle spielen wird. Die Fähigkeit, Vorlagen von Biomolekülen und/oder Anordungen mit definierten Eigenschaften zu schaffen und gleichzeitig ihre biologische Aktivität zu erhalten, kann als Beweis dienen, daß biologische Motoren für die molekulare Fertigung genutzt werden können. - (Die Druckexemplare enthalten jeweils eine CD-ROM als Anlagenteil: QuickTimeMovies (ca. 86 MB)- Übersicht über Inhalte siehe Dissertation S. IX - XIII)The work described in this thesis is in the field of NanoBioTechnology. Its goal is to leverage the motor protein kinesin and its microtubule track to manipulate DNA molecules in synthetic environment. This thesis contains five chapters. The first chapter describes macromolecular structures of the cell: i. e. the cytoskeleton and one of the motor proteins that move along it, kinesin. Emphasized is how biological motors might prove useful for organizing structures in engineered environments. The second chapter demonstrates how kinesin and microtubules can be used in synthetic environments to transport different cargos: i.e. streptavidin, quantum dots and DNA molecules. Special emphasis is placed on the manipulation of DNA molecules by the motor-driven microtubules. This cargo transport mechanism serves as a proof-of-principle for new bioengineering concepts such as DNA-based molecular electronics. The third chapter describes the influences of the surface properties on the DNA attachment and offers answers as how surface characteristics can be investigated, specifically designed and prepared so that they can serve the desired scientific purpose. The fourth chapter describes the manner in which DNA molecules can be attached to conductive surfaces and manipulated with motor proteins and microtubules. The complex DNA pattern formation that can be used for nanoelectronics is demonstrated. The advantages of motor-based manipulation over the conventional "one-by-one" methods (AFM, optical tweezers etc.) are discussed. The fifth and last chapter shows how one can use the kinesin-microtubule system to derive information about DNA molecules. For this, the response of the microtubules to forces exerted by attached DNA molecules has been studied. In summary, I have generated experimental assays and staining procedures to detect, visualize and control the entire manipulation process and to investigate its implications for theoretical analysis as well as for practical nano-engineered applications. My data demonstrated that DNA molecules can be manipulated in synthetic environment by kinesin and microtubules in such a way that controlled DNA biointerfaces can be generated. These biointerfaces can then be used for nanoelectronical application as well as for DNA topological studies. The kinesin-microtubule system is also expected to be equally important for 3D biomolecular assembly in engineered environments. The ability to generate templates of biomolecules and/or bioassemblies with well-defined features while maintaining their bioactivity, serves as proof-of-principle that biological motors can be used for molecular manufacturing. - (The pressure copies contain in each case a CD-ROM as component: QuickTimeMovies (ca. 86 MB)- To overview of contents see thesis P. IX - XIII)
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Žvingila, Donatas. "DNR žymenų panaudojimas augalų genominiams ir bioįvairovės tyrimams." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090305_092636-58705.
Full textAbstract:
DNR žymenys yra polimorfinių DNR lokusų aleliai, lokalizuoti tam tikrose genomo vietose ir nustatomi naudojant įvairius molekulinės biologijos metodus. Genetinės įvairovės nustatymas ir tyrimas naudojant DNR žymenis gali padėti suprasti daugelio biologinių reiškinių, vykstančių augaluose (ląstelės, organizmo, rūšies lygmenyje), prigimtį. Vykdydami aptariamus tyrimus norime rasti atsakymą į pagrindinį klausimą: kokios naudotų DNR žymenų galimybės kai kurioms augalų biologijos problemoms (genetinių išteklių išsaugojimo, adaptyvumo, populiacijų diferenciacijos, biotinio ir abiotinio streso ir kt.) spręsti? Naudodami įvairius DNR žymenis kaip molekulinius instrumentus, įvertinome genetinės įvairovės lygį pagrindinėse miežių veislėse, sukurtose Baltijos šalyse ir Baltarusijoje, pritaikėme DNR žymenų nustatymo metodus Rubus idaeus, Lonicera ceruleae genetinėse kolekcijose esančių pavyzdžių genotipavimui bei miško medžių (Pinus sylvestris, Piceae abies) rinktinių medžių klonų tapatumo nustatymui; naudodami EST žymenis klonavome ir ištyrėme du genus, dalyvaujančius Solanum tuberosum atsake į biotinį (Erwinia carotovora infekcija) ir abiotinį stresą. Naudodami RAPD metodą ištyrėme Saxifraga hirculus, Piceae abies, Fraxinus excelsior, Taxus baccata, Rubus idaeus, Pinus sylvestris populiacijų genetinę struktūrą, diferenciacijos lygį, kai kurių ekologinių veiksnių įtaką genetinės įvairovės pasiskirstymui populiacijose.DNA markers are alleles of polymorphic DNA loci that are established using methods of molecular biology and can be used for the identification of specific chromosome region. DNA markers are applied for the detection and analysis of genetic variation. These molecular instruments can help in the understanding of molecular basis of various biological phenomena in plants (loss of genetic diversity, population divergence, adaptivity, response to biotic and abiotic stress, genetic instability et cetera). The use of DNA markers in practical studies requires a careful consideration of the advantages and as well as limitations of various marker techniques. In this review various applications of DNA markers in plant genetic studies including genotyping and characterization of accessions of germplasm collections, assessment of genetic relationships between cultivars, understanding of the genetic variation within and between populations, plant genome analysis and gene cloning are discussed.
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Paulavičiūtė, Brigita. "Use of molecular markers in biochemical taxonomy of Tischeriidae (Lepidoptera: Tischerioidea) and Elachistidae (Lepidoptera: Gelechioidea)." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20101019_154349-34145.
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The field of molecular biology has expanded greatly in the last ten years and currently many entomologists want to use this technology since it is a new level of carrying out studies of insect ecological systems and taxonomy. The study of mitochondrial DNA (mtDNA) sequences has become the method for a wide range of taxonomic, population and evolutionary investigations in Lepidoptera (Lunt et al, 1996). The increasing popularity of molecular taxonomy will undoubtedly exert a major impact on conservation biology practice. The benefit of such approaches is undeniable since they will clearly be an asset to rapid biological assessments of poorly known taxa or unexplored areas, and to the discovery of cryptic biodiversity.
The Tischeriidae and Elachistidae represent rather small families as compared to many other groups of Lepidoptera. Moths are with wingspan from 6–13 mm. They are found all over the world, but most species are known from Boreal, Palearctic and Neotropical regions. These moths are leaf-miners during all larval instars. Molecular tools can help to identify this group. A lot of Tischeriidae and Elachistidae species are siblings externally, and their identification is very problematic, so in this case the structure of the male genital is more popular. However, only two articles dealt with the results of the mitochondrial DNA analysis in Elachista species from Australia (Kaila and Ståhls, 2006) and Tisheria ptarmica from the United Arab Emirates (Nieukerken, 2010)... [to full text]Molekuliniai žymenys yra polimorfinės DNR sekos lokalizuotos tam tikrose genomo vietose ir nustatomos naudojant įvairius molekulinės biologijos metodus. Jais nustatomi dviejų ar daugiau idividų ląstelėse esančios genetinės informacijos skirtumai. Morfologiniai žymenys naudojami ir šiandien, bet dėl įvairių trūkumų jų panaudojimas labai ribotas. Įvairūs molekuliniai tyrimo metodai vis dažniau naudojami entomologijoje (Loxdale, Lushai, 1998). Tiriant vabzdžių filogenezę ir sistematiką molekuliniai tyrimo metodai vis populiarėja, tačiau iki šiol jie nebuvo taikomi Tischeriidae ir Elachistidae šeimų drugių tokio pobūdžio tyrimuose. Šių šeimų drugiai filogenetiškai vieni primityviausių drugių būrio atstovai, jungiantys giminiškas šeimas. Tischeriidae ir Elachistidae drugiai plačiai paplitę tiek Baltijos regione, tiek visame pasaulyje, joms priklauso vieni mažiausių Žemėje mikro drugiai, kurie išsiskiria ne tik archaiška sandara, bet ir labai didele specializacija. Daugelio jų išskleistų sparnų ilgis tesiekia vos 6–13 mm. Daugelis Tischeriidae ir Elachistidae rūšių išoriškai yra panašios ir sunkiai atskiriamos, todėl pagrindinis dėmesys apibūdinant rūšį skiriamas patinų genitalijų struktūrai. Minuojantis gyvenimo būdas – svarbi primityvių Microlepidoptera biologinė adaptacija, suteikusi šiems vabzdžiams daug privalumų. Iki šiol molekulinių tyrimų su šiais drugiais atlikta ypač mažai, todėl visi publikuoti apžvalginiai darbai (tiek Lietuvos autorių, tiek užsienio mokslininkų), iki... [toliau žr. visą tekstą]
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Gerasimaitė, Rūta. "A directed evolution design of target specificity and kinetic analysis of conformational transitions in the HhaI methyltransferase." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110519_082240-87105.
Full textAbstract:
DNA cytosine-5 methyltransferases (MTases) recognize short DNA sequences and catalyze the transfer of the methyl group from the cofactor AdoMet to the C5-position of a target cytosine. In this work both these aspects of the MTase mechanism have been addressed. First, using rational protein design and directed evolution approaches the specificity of the HhaI MTase, GCGC, has been changed to GCG by functional elimination of one of the two target recognition elements. In addition, the introduced structural changes endowed the MTase with the ability to transfer extended groups from synthetic cofactor analogs, providing the first example of a dual specificity change in a DNA MTase.
Second, the kinetics of fast pre-catalytic conformational transitions in the MTase and DNA has been investigated. A new method to follow the target cytosine flipping and its subsequent covalent activation has been proposed, which allows a direct real-time observation of these processes by monitoring associated UV absorbance changes in a chemically unperturbed DNA. These studies for the first time demonstrate that the flipping of the target cytosine and the closure of the catalytic loop in the enzyme occur simultaneously, whereas the covalent activation of the target cytosine and the transfer of the methyl group are temporally distinct steps in the catalytic cycle of M.HhaI. Since the new method is based on the general phenomenon of hyperchromicity, it is thus applicable for studies of other systems... [to full text]DNR citozino-5 metiltransferazės (MTazės) atpažįsta specifines DNR sekas ir katalizuoja metilgrupės pernešimą nuo kofaktoriaus AdoMet ant taikinyje esančio citozino. Šiame darbe nagrinėjami abu MTazių veikimo mechanizmo aspektai. Baltymų inžinerijos ir kryptingos evoliucijos metodais pašalinant vienos iš dviejų taikinio atpažinimo kilpų funkciją, MTazės HhaI atpažįstamas taikinys GCGC pakeistas į GCG. Dėl įvestų struktūros pakeitimų nauja unikalaus specifiškumo MTazė efektyviai katalizuoja ne tik metilo, bet ir didesnių grupių pernešimą nuo sintetinių kofaktoriaus analogų, ir gali tapti naudingu molekulinės biologijos įrankiu. Katalitinės reakcijos metu MTazės kilpa užsidaro, apglėbdama surištą DNR, o taikinio citozinas išsukamas iš DNR spiralės ir aktyvuojamas, kovalentiškai prisijungiant katalitiniam cisteinui. Šiems greitiems prieškatalitiniams procesams tirti buvo panaudotas naujas metodas, leidžiantis realiu laiku stebėti M.HhaI sąlygotą citozino išsukimą bei kovalentinę aktyvaciją, registruojant mažus UV absorbcijos pokyčius gamtinį substratą atitinkančioje DNR. Pirmą kartą parodyta, kad M.HhaI katalizuojamoje reakcijoje citozino išsukimas ir katalitinės kilpos užsidarymas vyksta sinchroniškai, o kovalentinė citozino aktyvacija ir metilgrupės pernešimas yra kinetiškai netapačios katalitinio ciklo stadijos. Kadangi naujasis metodas remiasi fundamentine nukleorūgščių savybe – hiperchrominiu efektu, todėl jis gali būti naudojamas ir kitų DNR bazę išsukančių baltymų... [toliau žr. visą tekstą]
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Gerasimaitė, Rūta. "DNR metiltransferazės HhaI atpažįstamos sekos inžinerija ir konformacinių virsmų kinetikos tyrimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2011~D_20110519_082408-25550.
Full textAbstract:
DNR citozino-5 metiltransferazės (MTazės) atpažįsta specifines DNR sekas ir katalizuoja metilgrupės pernešimą nuo kofaktoriaus AdoMet ant taikinyje esančio citozino. Šiame darbe nagrinėjami abu MTazių veikimo mechanizmo aspektai. Baltymų inžinerijos ir kryptingos evoliucijos metodais pašalinant vienos iš dviejų taikinio atpažinimo kilpų funkciją, MTazės HhaI atpažįstamas taikinys GCGC pakeistas į GCG. Dėl įvestų struktūros pakeitimų nauja unikalaus specifiškumo MTazė efektyviai katalizuoja ne tik metilo, bet ir didesnių grupių pernešimą nuo sintetinių kofaktoriaus analogų, ir gali tapti naudingu molekulinės biologijos įrankiu.
Katalitinės reakcijos metu MTazės kilpa užsidaro, apglėbdama surištą DNR, o taikinio citozinas išsukamas iš DNR spiralės ir aktyvuojamas, kovalentiškai prisijungiant katalitiniam cisteinui. Šiems greitiems prieškatalitiniams procesams tirti buvo panaudotas naujas metodas, leidžiantis realiu laiku stebėti M.HhaI sąlygotą citozino išsukimą bei kovalentinę aktyvaciją, registruojant mažus UV absorbcijos pokyčius gamtinį substratą atitinkančioje DNR. Pirmą kartą parodyta, kad M.HhaI katalizuojamoje reakcijoje citozino išsukimas ir katalitinės kilpos užsidarymas vyksta sinchroniškai, o kovalentinė citozino aktyvacija ir metilgrupės pernešimas yra kinetiškai netapačios katalitinio ciklo stadijos. Kadangi naujasis metodas remiasi fundamentine nukleorūgščių savybe – hiperchrominiu efektu, todėl jis gali būti naudojamas ir kitų DNR bazę išsukančių baltymų... [toliau žr. visą tekstą]DNA cytosine-5 methyltransferases (MTases) recognize short DNA sequences and catalyze the transfer of the methyl group from the cofactor AdoMet to the C5-position of a target cytosine. In this work both these aspects of the MTase mechanism have been addressed. First, using rational protein design and directed evolution approaches the specificity of the HhaI MTase, GCGC, has been changed to GCG by functional elimination of one of the two target recognition elements. In addition, the introduced structural changes endowed the MTase with the ability to transfer extended groups from synthetic cofactor analogs, providing the first example of a dual specificity change in a DNA MTase. Second, the kinetics of fast pre-catalytic conformational transitions in the MTase and DNA has been investigated. A new method to follow the target cytosine flipping and its subsequent covalent activation has been proposed, which allows a direct real-time observation of these processes by monitoring associated UV absorbance changes in a chemically unperturbed DNA. These studies for the first time demonstrate that the flipping of the target cytosine and the closure of the catalytic loop in the enzyme occur simultaneously, whereas the covalent activation of the target cytosine and the transfer of the methyl group are temporally distinct steps in the catalytic cycle of M.HhaI. Since the new method is based on the general phenomenon of hyperchromicity, it is thus applicable for studies of other systems... [to full text]
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Masiokas, Andrius. "Paprastųjų uosių (Fraxinus excelsior L.), besiskiriančių džiūvimo laipsniu, palikuonių išauginimas in vitro ir genetinės įvairovės įvertinimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100621_114629-24771.
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Darbo objektas – Alyvmedinių (Oleaceae) šeimos uosinių (Fraxinus) genties medis - paprastasis uosis (Fraxinus excelsior L.). Darbo tikslas – Išauginti in vitro paprastųjų uosių (Fraxinus excelsior L.), besiskiriančių džiūvimo laipsniu, palikuonis ir atlikti genetinės įvairovės įvertinimą. Darbo metodai – regeneravusių mikroūglių įvertinimas, palikuonių DNR nustatymas. Darbo rezultatai. Atlikus tyrimus įvertintos paprastojo uosio išauginimo in vitro sąlygos ir nustatyta genetinė įvairovė. Eksplantų sterilinimui tikslinga naudoti aseptinių tirpalų kombinaciją su „ACE“ ir AgNO3 0,2 proc., kad užtikrinti gyvybingų ir be užkrato eksplantų išlikimą. Aktyviausiai mikroūgliai regeneravo WPM (Woody Plant Medium) terpėje, kurios pH 5,0. Gyvybingiausi regenerantai atitinka mažiausiai pažeistą uosį pagal džiūvimo laipsnį. Sveikiausio genotipo uosių ex vitro sąlygomis adaptavosi 92 proc., labiausiai pažeisto - 53 proc. Tirtų dviejų paprastojo uosio individų turėjo skirtingus APPD fenotipus su naudotais dviem informatyviais pradmenimis.The research object. – Oleaceae (Oleaceae) family of Ash (Fraxinus) tree of the genus - ash (Fraxinus excelsior L.). The aims of the study – Grown in vitro for common ash (Fraxinus excelsior L.), distinguished by the degree of drying, and a descendant of the genetic diversity assessment. Methods – regenerant microshoots evaluation of DNA detection. The results. After the tests evaluated in plain ash grown in vitro conditions and the genetic diversity. For explants sterile appropriate to use a combination of aseptic solutions with ACE and 0.2 percent AgNO3. to ensure the viability and survival of the explants without contamination. The most active shoots regenerate WPM (Woody Plant Medium) medium with pH 5.0. The most lively regenerants the least damaged ash according to the degree of drying. Healthiest genotype ashes of ex vitro specialized 92 percent. The most damaged - 53 percent. The results from two-ordinary ash individuals had different phenotypes APPD to use two informative primers.
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Bärmann, Daniel. "Aufzählen von DNA-Codes." Master's thesis, Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2006/1026/.
Full textAbstract:
In dieser Arbeit wird ein Modell zum Aufzählen von DNA-Codes entwickelt.
Indem eine Ordnung auf der Menge aller DNA-Codewörter eingeführt und auf die Menge aller Codes erweitert wird, erlaubt das Modell das Auffinden von DNA-Codes mit bestimmten Eigenschaften, wie Überlappungsfreiheit, Konformität, Kommafreiheit, Stickyfreiheit, Überhangfreiheit, Teilwortkonformität und anderer bezüglich einer gegebenen Involution auf der Menge der Codewörter. Ein auf Grundlage des geschaffenen Modells entstandenes Werkzeug erlaubt das Suchen von Codes mit beliebigen Kombinationen von Codeeigenschaften.
Ein weiterer wesentlicher Bestandteil dieser Arbeit ist die Untersuchung der Optimalität von DNA-Codes bezüglich ihrer Informationsrate sowie das Finden solider DNA-Codes.In this work a model for enumerating DNA codes is developed. By applying an order on the set of DNA codewords and extending this order on the set of codes, this model assists in the discovery of DNA codes with properties like non-overlappingness, compliance, comma-freeness, sticky-freeness, overhang-freeness, subword-compliance, solidness and others with respect to a given involution on the set of codewords. This tool can be used to find codes with arbitrary combinations of code properties with respect to the standard Watson-Crick-DNA involution. The work also investigates DNA codes with respect to the optimizing of the information rate, as well as finding solid DNA codes.
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Hajkova, Petra. "Epigenetic reprogramming in mouse germ cells." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2004. http://dx.doi.org/10.18452/15020.
Full textAbstract:
Bei Säugerkeimzellen, Zygoten und Embryos in frühen Stadien kommt der epigenetischen Neuprogammierung eine außergewöhnlich wichtige Rolle in der Regulation der Genomfunktionen in entscheidenden Entwicklungsstadien zu. Die epigenetische Neuprogrammierung in Keimzellen löscht zuerst die Imprinting-Markierungen und Epi-Mutationen und stellt dann geschlechtsspezifische Markierungen (genomische Prägung) wieder her. Die vorliegende Arbeit bezieht sich auf das Löschen epigenetischer Modifikationen in primordialen Mauskeimzellen (primordial germ cells (PGCs)) zwischen dem 10.5 bis 13.5 Tag nach der Befruchtung. Entgegen früheren Annahmen zeigen unsere Ergebnisse, daß primordiale Mauskeimzellen (PGCs) beim Eintritt in die embryonalen Keimdrüsen noch immer DNS Methylierungsmarker besitzen, die ähnlich dem Marker in somatischen Zellen sind. Kurz nach dem Eintritt in die Keimdrüsen werden die DNS Methylierungsmarker, die in Verbindung mit geprägten und nicht geprägten Genen stehen, gelöscht. Für die Mehrzahl der Gene beginnt die Löschung der Marker in männlichen und weiblichen Embryos gleichzeitig und ist innerhalb eines Entwicklungstages abgeschlossen. Diese Kinetik deutet auf einen aktiven Demethylierungsprozess hin, initiiert durch ein somatisches Signal, ausgehend von der embryonalen Keimdrüse. Der Zeitpunkt der Neuprogrammierung in den primordialen Keimzellen ist entscheidend, da er sicherstellt, daß Keimzellen beiden Geschlechts einen epigenetisch äquivalenten Status erhalten, bevor sie geschlechtsspezifisch ausdifferenzieren und anschließend neu elterlich geprägt werden. Vollständiges Verständnis des Prozesses der Neuprogrammierung der Keimzellen ist nicht nur im Hinblick auf genomisches Imprinting wichtig, sondern auch für die Erforschung von Mechanismen für die Wiederherstellung von omnipotenten Zellen bei Klonierung und Stammzellenerhaltung.Epigenetic reprogramming in mammalian germ cells, zygote and early embryos, plays a crucial role in regulating genome functions at critical stages of development. Germ line epigenetic reprogramming assures erasure of all the imprinting marks and epi-mutations and establishment of new sex-specific gametic imprints. The presented work focuses on the erasure of epigenetic modifications that occur in mouse primordial germ cells (PGCs) between day 10.5 to 13.5 post coitum (dpc). Contrary to previous assumptions, our results show that as they enter the genital ridge the PGCs still possess DNA methylation marks comparable to those found in somatic cells. Shortly after the entry of PGCs into the gonadal anlagen the DNA methylation marks associated with imprinted and non-imprinted genes are erased. For most genes the erasure commences simultaneously in PGCs of both male and female embryos and is completed within only one day of development. The kinetics of this process indicates that is an active demethylation process initiated by a somatic signal emanating from the stroma of the genital ridge. The timing of reprogramming in PGCs is crucial since it ensures that germ cells of both sexes acquire an equivalent epigenetic state prior to the differentiation of the definitive male and female germ cells in which, new parental imprints are established subsequently. Complete understanding of the germline reprogramming processes is important not only in the light of genomic imprinting but also for resolving other mechanisms connected with restoring cellular totipotency, such as cloning and stem cell derivation.
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Boroudjerdi, Hoda. "Charged polymer-macroion complexes." Phd thesis, Universität Potsdam, 2005. http://opus.kobv.de/ubp/volltexte/2006/628/.
Full textAbstract:
This work explores the equilibrium structure and thermodynamic phase behavior
of complexes formed by charged polymer chains (polyelectrolytes) and oppositely
charged spheres (macroions).
Polyelectrolyte-macroion complexes form a common pattern in soft-matter physics,
chemistry and biology, and enter in numerous technological applications as well.
From a fundamental point of view, such complexes are interesting in that
they combine the subtle interplay between electrostatic interactions and elastic as well as entropic
effects due to conformational changes of the polymer chain, giving rise
to a wide range of structural properties.
This forms the central theme of theoretical studies presented in this thesis, which
concentrate on a number of different problems
involving strongly coupled complexes, i.e. complexes that are characterized by
a large adsorption energy and small chain fluctuations.
In the first part, a global analysis of the structural phase behavior of a single polyelectrolyte-macroion complex is presented based on a dimensionless representation, yielding results that cover a wide range of realistic system parameters. Emphasize is made on the interplay between the effects due to the polyelectrolytes chain length, salt concentration and the macroion charge as well as the mechanical chain persistence length. The results are summarized into generic phase diagrams characterizing the wrapping-dewrapping behavior of a polyelectrolyte chain on a macroion. A fully wrapped chain state is typically obtained at intermediate salt concentrations and chain lengths, where the amount of polyelectrolyte charge adsorbed on the macroion typically exceeds the bare macroion charge leading thus to a highly overcharged complex.
Perhaps the most striking features occur when a single long polyelectrolyte chain is complexed with many oppositely charged spheres. In biology, such complexes form between DNA (which carries the cell's genetic information) and small oppositely charged histone proteins serving as an efficient mechanism for packing a huge amount of DNA into the micron-size cell nucleus in eucaryotic cells. The resultant complex fiber, known as the chromatin fiber, appears with a diameter of 30~nm under physiological conditions. Recent experiments indicate a zig-zag spatial arrangement for individual DNA-histone complexes (nucleosome core particles) along the chromatin fiber. A numerical method is introduced in this thesis based on a simple generic chain-sphere cell model that enables one to investigate the mechanism of fiber formation on a systematic level by incorporating electrostatic and elastic contributions. As will be shown, stable complex fibers exhibit an impressive variety of structures including zig-zag, solenoidal and beads-on-a-string patterns, depending on system parameters such as salt concentration, sphere charge as well as the chain contour length (per sphere). The present results predict fibers of compact zig-zag structure within the physiologically relevant regime with a diameter of about 30~nm, when DNA-histone parameters are adopted.
In the next part, a numerical method is developed in order to investigate the role of thermal fluctuations on the structure and thermodynamic phase behavior of polyelectrolyte-macroion complexes. This is based on a saddle-point approximation, which allows to describe the experimentally observed reaction (or complexation) equilibrium in a dilute solution of polyelectrolytes and macroions on a systematic level. This equilibrium is determined by the entropy loss a single polyelectrolyte chain suffers as it binds to an oppositely charged macroion. This latter quantity can be calculated from the spectrum of polyelectrolyte fluctuations around a macroion, which is determined by means of a normal-mode analysis. Thereby, a stability phase diagram is obtained, which exhibits qualitative agreement with experimental findings.
At elevated complex concentrations, one needs to account for the inter-complex interactions as well. It will be shown that at small separations, complexes undergo structural changes in such a way that positive patches from one complex match up with negative patches on the other. Furthermore, one of the polyelectrolyte chains may bridge between the two complexes. These mechanisms lead to a strong inter-complex attraction. As a result, the second virial coefficient associated with the inter-complex interaction becomes negative at intermediate salt concentrations in qualitative agreement with recent experiments on solutions of nucleosome core particles.
In dieser Arbeit werden Gleichgewichtsstrukturen und die thermodynamischen Phasen von Komplexen aus geladenen Polymeren (Polyelektrolyten) und entgegengesetzt geladenen Kugeln (Makroionen) untersucht. Polyelektrolyt-Makroion-Komplexe bilden ein grundlegendes und wiederkehrendes Prinzip in der Physik weicher Materie sowie in Chemie und Biologie. In zahlreichen technologischen Prozessen finden sich ebenfalls Anwendungsbeispiele für derartige Komplexe. Zusätzlich zu ihrem häufigen Auftreten sind sie aufgrund ihrer Vielfalt von strukturellen Eigenschaften von grundlegendem Interesse. Diese Vielfalt wird durch ein Zusammenspiel von elektrostatischen Wechselwirkungen sowie elastischen und entropischen Effekten aufgrund von Konformationsänderungen in der Polymerkette bedingt und bildet das zentrale Thema der theoretischen Studien, die mit dieser Arbeit vorgelegt werden. Verschiedene Strukturen und Prozesse, die stark gekoppelte Komplexe beinhalten - das sind solche, für die eine hohe Adsorptionsenergie und geringe Fluktuationen in den Polymerketten charakteristisch sind -, bilden das Hauptthema der Arbeit.
Basierend auf einer dimensionslosen Darstellung wird im ersten Teil der Arbeit in einer umfassenden Analyse das strukturelle Phasenverhalten einzelner Polyelektrolyt-Makroion-Komplexe behandelt. Der Schwerpunkt wird hier auf das Wechselspiel zwischen Effekten aufgrund der Polyelektrolytkettenlänge, ihrer mechanischen Persistenzlänge, der Salzkonzentration und der Ladung des Makroions gelegt. Die Ergebnisse werden in allgemeinen Phasendiagrammen zusammengestellt, das das Aufwickeln-Abwickeln-Verhalten der Polyelektrolytkette auf einem Makroion beschreibt. Ein Zustand mit komplett aufgewickelter Kette tritt typischerweise bei mittleren Salzkonzentrationen und Kettenlängen auf; häufig ist hier die auf dem Makroion adsorbierte Gesamtladung des Polyelektrolyts größ er als die Ladung des nackten Makroions, d.h. es findet in hohem Grad Ladungsinversion statt.
Äußerst bemerkenswerte Eigenschaften treten auf, wenn eine einzelne lange Polyelektrolytkette viele, ihr entgegengesetzt geladene Kugeln komplexiert. In biologischen Systemen findet man solche Komplexe zwischen DNS, die die genetische Information einer Zelle trägt, und kleinen, entgegengesetzt geladenen Histonproteinen. Diese Komplexe dienen als effizienter Mechanismus, die groß e Menge an DNS im Mikrometer-groß en Zellkern eukaryotischer Zellen zu komprimieren. Die dadurch erhaltene komplexe Faser, eine Chromatinfaser, hat unter physiologischen Bedingungen einen Durchmesser von nur etwa 30~nm. Neue Experimente haben gezeigt, dass eine räumliche Zickzack-Anordnung einzelner DNA-Histon-Komplexe entlang der Chromatinfaser vorliegt. In der hier vorgelegten Arbeit wird eine numerische Methode vorgestellt, die auf einem einfachen Ketten-Kugel-Zell-Modell basiert und die die systematische Untersuchung des Mechnismus zur Faserbildung ermöglicht, wobei sowohl elektrostatische als auch elastische Wechselwirkungen berücksichtigt werden. Es wird gezeigt, dass stabile Komplexfasern in Abhängigkeit von der Salzkonzentration, der Kugelladung und der Kettenkonturlänge eine Vielfalt von Strukturen aufweisen, darunter Zickzack-, Solenoid- und Perlenkettenformen. Für physiologisch relevante Bedingungen werden mit dieser Methode für DNA-Histon-Komplexe Fasern kompakter Zickzack-Struktur mit einem Durchmesser von etwa 30~nm erhalten.
Im folgenden Teil wird eine numerische Methode entwickelt, um den Einfluss thermischer Fluktuationen auf Struktur und thermodynamisches Phasenverhalten der Polyelektrolyt-Makroion-Komplexe zu untersuchen. Basierend auf der Sattelpunktsnäherung werden die experimentell beobachteten Reaktionsgleichgewichte in verdünnten Lösungen von Polyelektrolyten und Makroionen systematisch beschrieben. Das Gleichgewicht ist durch einen Verlust an Entropie für die einzelne Polyelektrolytkette durch die Bindung an das entgegengesetzt geladene Makroion gekennzeichnet. Diese Größ e wurde aus dem Spektrum der Polyelektrolytfluktuationen um das Makroion erhalten und mittels einer Analyse der Normalmoden berechnet. Hierüber wird ein Phasendiagramm zur Stabilität der Komplexe erhalten, das qualitativ gute Übereinstimmungen mit experimentellen Ergebnissen aufweist.
Bei höheren Komplexkonzentrationen müssen auch die Wechselwirkungen zwischen den Komplexen berücksichtigt werden. Es wird gezeigt, dass sich die Struktur der Komplexe bei kleinen Abständen so ändert, dass positiv geladene Bereiche eines Komplexes mit negativ geladenen auf einem Nachbarkomplex räumlich korrelieren. Weiterhin können einzelne Polyelektrolytketten als verbrückendes Element zwischen zwei Komplexen dienen. Dieser Mechanismus führt zu starker effektiver Anziehung zwischen den Komplexen. In Übereinstimmung mit kürzlich durchgeführten Experimenten ist als Folge davon der zweite Virialkoeffizient der Wechselwirkung zwischen Komplexen bei mittleren Salzkonzentrationen negativ.
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Gouws, Chrisna. "Tyrosinemia type I as a model for studying epigenetic events in the aetiology of metabolic disease associated hepatocarcinoma / Gouws, C." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7010.
Full textAbstract:
Occupational risk management can be a catalyst in generating superior returns for all stakeholders on a sustainable basis. A number of companies in South Africa have implemented Cardinal Rules of Safety adopted from international companies to ensure the safety of their employees. The purpose of this study was to measure the impact of the cardinal rules on employee safety behaviour implemented at power stations in Mpumalanga.
The empirical study was done by using a questionnaire as measuring instrument. The questionnaire was developed from a literature review and contains questions and items relevant to the initial research problem. The questionnaire comprised of five–point Likert scale type questions.The convenience sampling method was applied identifying 90 participants at three different power stations in Mpumalanga taking part in the study.
Statistical analysis was performed by the Statistical Consulting Service of the North–West University using SPSS. Cronbach’s alpha co–efficients was used to determine the reliability of the factors. Descriptive statistics (Mean, standard, deviation, were used in the compiling of the profile of the results. While Spearman’s rho correlation coefficient was calculated to identify practically significant associations between variables and factors
The research findings suggest that there is practical significant correlation between the factors that were measured. The opinion given by respondents suggests that cardinal rules of safety were implemented, given all the necessary support by management and enforced throughout the organisation.Thesis (Ph.D. (Biochemistry))--North-West University, Potchefstroom Campus, 2012.
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Draudvilaitė, Kristina. "Žemaitukų mitochondrinės DNR konrolinės sekos nustatytmas ir palyginimas skirtingose arklių veislėse." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050413_083701-74154.
Full textAbstract:
The objective - To identify Zemaitukai mtDNA D-loop region and genetic relationships between Zemaitukai and some other breeds based on mtDNA sequence variation.
Methods - To perform a phylogenetic analysis of 10 Zemaitukai, mtDNA D-loop 49 horses in the 20 different horse breeds sequence were included from GenBank (http://www.ncbi.nlm.nih.gov/GenBank). DNA was extracted from hair roots using the DNEasy® Tissue Kit (Qiagen). 1,280 bp fragment of mtDNA D-loop were amplify out in PTC-100™ termocycler. Amplified products were sequenced on a LI-COR® 4200S-2 automated sequencer. Sequencher v 4.1.4. software package was used to generate the actual DNA sequence for each of the animals. Multiple alignments of sequences were performed with CLUSTAL X 1.8 (Thompson et al., 1997). The Neighbor-joining tree (Saitou and Nei, 1987) of mtDNA sequences was constructed from Jukes-Cantor distances, performed on the pairwise deletion using the MEGA software (Kumar et al., 1993).
Results –Within Zemaitukai breed 19 polymorphic sites were detected and 6 haplotypes. At the individual level 4 zemaitukai haplotypes were private to one individuals, 1 haplotype-between 2 individuals and 1 haplotype was shared between 4 individuals. On the Neighbor-joining tree showed one Zemaitukai haplotype closer genetic relationships to the Icelandic and to the Norwegian Fiord horse haplotypes. Zemaitukai breed formed a separate branch with the ancient DNA haplotype. The phylogenetic analysis reflects the presence... [to full text]
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Ragauskas, Adomas. "Lietuvos upinių ungurių - Anguilla anguilla (L.) vidurūšinės genetinės įvairovės tyrimas naudojant mikrosatelitinius DNR žymenis." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2011. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2008~D_20110709_152245-13179.
Full textAbstract:
Šio darbo metu naudojant 5 mikrosatelitinius DNR žymenis buvo bandoma išsiaiškinti, ar į Lietuvą natūraliai atplaukiantys upiniai unguriai skiriasi nuo į Lietuvą introdukuotų upinių ungurių genetiškai. Vietines Anguilla anguilla populiacijas atstovavo Baltijos jūros ir Kuršių marių imtys, o introdukuotas – Dringio ir Siesarčio ežerų imtys. Tikrinama buvo, tiek izoliacijos dėl atstumo (IBD), tiek laikinės izoliacijos (IBT), įtaka A. anguilla genetinei diferenciacijai. Nors genetinė diferenciacija tarp didžiosios dalies lyginamų imčių buvo maža (FST = 0,0042) ir nepatikima (p > 0,05), tačiau remdamiesi gautais tyrimo rezultatais negalime patvirtinti panmiksinės hipotezės A. anguilla rūšyje, kadangi mažos (FST = 0,0143) ir patikimos (p = 0,0018) genetinės diferenciacijos nustatymas tarp Siesarčio ežero introdukuotų upinių ungurių leidžia teigti, kad genetinė diferenciacija Anguilla anguilla rūšyje egzistuoja.In order to find out whether native and introduced Anguilla anguilla populations differ one from another genetically I have used 5 microsatellite markers and compared 2 native between 2 introduced European eel samples. Native A. anguilla samples were taken from Baltic sea and Curonian lagoon, while introduced samples were taken from Dringis and Siesartis lakes. During this work I tried to find out not only IBD, but also IBT impact to A. anguilla genetic differentiation. Experiment results do not reject panmixia hypothesis in European eel, because there are small (FST = 0,0042) and not significant (p > 0,05) genetic differentiation among all samples used in this experiment. However, there is no enough data to say that A. anguilla genetic differentiation does not exist at all, because there is small (FST = 0,0143) and significant (p = 0,0018) genetic differentiation among lake Siesartis samples.
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Kerpauskaitė, Vilma. "Skirtingų paprastosios pušies (Pinus Sylvestris L.) lajos dalių sėklinių palikuonių genetinės įvairovės palyginimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120620_150922-88975.
Full textAbstract:
Magistro darbe lyginama vieno paprastosios pušies (Pinus sylvestris L.) klono skirtingų lajos dalių sėklinių palikuonių, augančių Višakio Rūdos bandomuosiuose želdiniuose, genetinė įvairovė remiantis DNR žymenimis ir kokybiniais bei kiekybiniais požymiais.
Darbo objektas – paprastosios pušies (Pinus sylvestris L.) sėklinių palikuonių želdiniai iš skirtingų lajos dalies sėklų (viršutinės, vidurinės, apatinės).
Darbo metodai – genetinė įvairovė tirta atliekant želdinių kiekybinių ir kokybinių požymių analizę bei jų DNR polimorfizmo tyrimą.
Darbo rezultatai. Fenotipinių požymių tyrimai parodė, kad 24 m amžiuje, viršutinės lajos dalies sėkliniai palikuonys pasižymi ženkliai didesniu išlikimu, bet esminiai nesiskiria savo kiekybinių ir kokybinių požymių įvairove nuo apatinės lajos dalies palikuonių. Gali būti, kad fenotipinių požymių įvairovei atsiskleisti trukdo nevienodas medžių išlikimas, kur esant mažesniam išlikimui, susidaro nevienodi tarpai tarp medžių, galėję įtakoti didesnę erdvinę įvairovę radialiniam prieaugiui. 6 chloroplasto DNR(cpSSR) lokusų DNR polimorfizmo tyrimai parodė, kad viršutinės lajos dalies sėklinių palikuonių genetinė įvairovė yra ženkliai didesnė nei vidurines ir apatinės lajos dalių sėklinių palikuonių. Iš 30 skirtingų cpSSR tipų (tėvinių genotipų) 18 buvo aptikti viršutinės lajos dalies palikuonyse, tuo tarpu vidurinėje dalyje – 8, o apatinėje - 10 .Visi 5 proc. savidulkinių individų aptikti tarp apatinės ir centrinės lajos dalies palikuonių (18 vnt.)... [toliau žr. visą tekstą]The genetic diversity of the progeny from different parts of Scots pine crown of a single clone by quantitative and qualitative traits and DNA polymorphism was investigated in the work of master science. Object of the work - 24 years old progeny from different parts of Scots pine crown of a single clone. The aim of the study - to compare the diversity of quantitative and qualitative traits and DNA polymorphism of24 years old progeny from different parts of Scots pine crown of a single clone by using cpSSR DNA markers. Methods of the work - Survival, stem diameter, stem straightness, flowering, cone yield, barktype,condition,the beginning of activegrowth and other parameters of the seedling progenies were evaluated. The genetic diversity was assessed at six cpDNA loci by the aid of cpSSRs. Study results. The results showed, that the survival of the progeny from the middle and the bottom of the crown was much lower than from the top. However, there were not any significant differences nor in the other traits neither between the variances of the progeny from the different parts of the crown. A reason could be that owing to low survival of the bottom and middle progeny, the remaining trees grew in a wider spacing and this uneven spacing between the treatments disturbed the comparison. cpSSR markers revealed much greater haplotype and allele diversity of the progeny from the top of the crown. Selfing rate was 5; background pollination 50; as much as 28 of the progeny from the... [to full text]
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Komori, Hirofumi. "Structural studies on DNA-binding proteins : DNA replication initiator and DNA photolyase." 京都大学 (Kyoto University), 2002. http://hdl.handle.net/2433/150005.
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Bandholtz, Lisa Charlotta. "DNA vaccines and bacterial DNA in immunity /." Stockholm, 2002. http://diss.kib.ki.se/2002/91-7349-340-6/.
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Boal, Amie Kathleen Parker Carl Stevens Barton Jacqueline K. "DNA-mediated charge transport in DNA repair /." Diss., Pasadena, Calif. : California Institute of Technology, 2008. http://resolver.caltech.edu/CaltechETD:etd-06022008-092549.
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Richardson, James Alistair. "Novel DNA probes for sensitive DNA detection." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/173981/.
Full textAbstract:
The ability to detect and interrogate DNA sequences allows further understanding and diagnosis of genetic disease. The ability to perform such analysis of genetic material requires highly selective and reliable technologies. Furthermore techniques which can use simple and cheap equipment allow the use of such technologies for point of care analysis. Described in this thesis are two novel DNA probe systems designed for mutation discrimination and sequence recognition of PCR products. A homogenous PCR system using HyBeacons® which utilise FRET to produce a three probe multiplex system and surface enhanced Raman detection method. Both of these systems allow multiplex detection of PCR products and mutation discrimination by melting temperature analysis. The research reported includes investigations into the effects of different modifications to improve the performance of HyBeacon® probes as well as the effect of different dyes in a FRET system, including unique changes in the optical properties of such dyes. Also a novel method of performing melting temperature analysis using an electrochemical potential is reported. In addition to the detection methods described this thesis includes initial work into the stabilisation of quantum dot nanoparticles for their use in aqueous systems as a potential alternative to fluorescent organic molecules.
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Lo, Pik Kwan Peggy. "Supramolecular DNA chemistry: assembly of DNA nanotubes and templated synthesis of DNA-mimetic polymers." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95152.
Full textAbstract:
DNA has emerged as a promising template for the programmable assembly of structures on the nanometer scale. In particular, DNA nanotubes hold promise for a number of biological and materials applications, because of their high aspect ratio and encapsulation potential. Current construction methods result in symmetrical and cylindrical assemblies that are totally double-stranded, and are long and polydisperse. In order to investigate DNA nanotubes for applications as well-defined molecular hosts and one-dimensional templates, better control over their geometry, stiffness and porosity, ability to encapsulate and length needs to be achieved. Specifically, the first section of this thesis will describe (a) a modular approach to construct DNA nanotubes of geometrically well-defined triangular and square-shapes, which can exist in either double- and single-stranded forms with different stiffnesses, (b) the construction of DNA nanotubes with longitudinal variation by alternating larger and smaller capsules along the tube length, the encapsulation of guest molecules within these DNA nanotubes as well as their selective release with externally added DNA strands, (c) the use of a DNA-templated approach to produce nanotubes with controlled pre-determined lengths of 1 μm, and 500 nm and narrow length distributions, and the encapsulation of gold nanoparticles within these well-defined nanotubes to form finite lines of gold nanoparticles with longitudinal plasmon coupling. While DNA is a very promising construction material, it suffers from serious drawbacks for practical applications in materials science and biology. DNA is difficult and expensive to obtain in large quantities, and has limited long-term stability. On the other hand, synthetic polymers are routinely used as building blocks for nanostructured materials, with multiple applications in areas ranging from optics and data storage, to separation science and biology. Thus, an important challenge is the creation ofL'ADN s'est récemment manifesté comme un matériau prometteur pour l'assemblage programmable de structures à l'échelle nanométrique. En particulier, les nanotubes d'ADN sont intéressants pour leurs applications en science des matériaux et en biologie, en raison de leur aspect linéaire et leur potentiel d'encapsulation. Les méthodes courantes de leur synthèse produisent des assemblées symétriques et cylindriques totalement constituées de doubles brins d'ADN longs et polydisperses. Afin d'examiner les nanotubes d'ADN pour leurs applications comme des hôtes moléculaires à structure bien-définie et comme modèles unidimensionnels, des méthodes de synthèse qui mènent à un plus haut niveau de contrôle de leur géométrie, rigidité, porosité, capacité d'encapsulation et longueur doivent être développées. Plus précisément, la première section de cette thèse décrira (a) une approche modulaire pour construire des nanotubes d'ADN géométriquement bien définis, triangulaires ou carrés, et pouvant exister en formes d'ADN double-brin ou brin simple avec des différences de rigidité, (b) la construction des nanotubes d'ADN avec une variation longitudinale, en alternant les grandes et les petites capsules le long du tube, et l'encapsulation de matériaux invités au sein de ces nanotubes d'ADN, ainsi que leur libération sélective sous l'action de brins d'ADN externes ajoutés, (c) l'utilisation de l'approche d'un modèle d'ADN pour produire des nanotubes avec des longueurs contrôlées et prédéterminées de 1 µm ou de 500 nm et des distributions de longueurs étroites, et l'encapsulation de nanoparticules d'or au sein de ces nanotubes bien définis pour former des lignes de longueurs bien définies de nanoparticules d'or avec un couplage plasmonique longitudinal. Bien que l'ADN soit une molécule très intéressante pour l'auto-assemblage de structures, son utilisation comme un outil dans les applications pratiques en science des maté
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Araki, Kasumi. "Dual roles for DNA polymerase η in homologous DNA recombination and translesion DNA synthesis." Kyoto University, 2006. http://hdl.handle.net/2433/143860.
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Pearson, Christopher Edmund. "DNA cruciforms and mammalian origins of DNA replication." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28503.
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The objective of the research in this thesis is to investigate, at the molecular level, the sequences and/or structures involved in the initiation of mammalian DNA replication and to investigate the protein interactions with DNA cruciforms which have been implicated in the process of replication initiation. Four plasmids containing monkey (CV-1) early replicating nascent origin enriched sequences (ors), which had been shown previously to replicate autonomously in transfected CV-1, COS-7 and HeLa cells, were used in the establishment of an in vitro DNA replication system that uses HeLa cell extracts. The in vitro replication system is dependent upon the presence of an ors sequence, and HeLa cell extracts. Mapping experiments indicate that there is preferential nucleotide incorporation in the ors sequences, suggesting site-specific initiation, and that replication is bidirectional and semiconservative. Electron microscopy confirmed that in vitro initiation occurs within the ors sequence.Prokaryotic and eukaryotic viral replication origins, mammalian origin enriched sequences (ors) and other mammalian early replicating sequences contain AT-rich sequences and inverted repeats, which have the potential to form bent and cruciform (stem-loop) DNA structures, respectively. Cruciforms have been postulated to form transiently at or near origins to serve as recognition structures for initiator proteins. Using a stable-DNA cruciform as a binding substrate in a band-shift assay, a novel DNA binding activity with specificity for the cruciform-containing DNA and no apparent sequence-specificity was identified in HeLa cell extracts. The activity is protein-dependent and is void of detectable nuclease activity. Cruciform-specific binding was observed to be maximal in early-S phase extracts. A novel cruciform binding protein (CBP) with an apparent molecular weight of 66 kDa was enriched from HeLa cell extracts. Footprinting experiments localized the CBP-DNA cruciform interaction to the four-way junction at the base of the cruciform. CBP appears to interact with the elbow junctions in an asymmetric fashion. Upon CBP binding, structural distortions were observed at the cruciform stems and at a DNA region distal to the junction.
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Grundström, Malin. "DNA : Att tillvarata DNA på ett rättssäkert sätt." Thesis, Umeå University, Basic training programme for Police Officers, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-27188.
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Syftet med arbetet är att belysa problematiken kring DNA som ett bevisinstrument, hur de olika analysformerna går till samt att påvisa vikten av att även polispersonal i yttre tjänst förstår hur och varför det är så viktigt att det tillvaratas på rätt sätt. Det finns mycket litteratur om DNA och jag har försökt begränsa mitt material till de delar som kan intressera poliser. Jag har även försökt att förklara DNA på ett så lätt sätt som möjligt för att den som inte är så bevandrad i biologi skall kunna förstå ett ändå mycket komplext ämne. Företrädelsevis har jag använt mig av skriftlig litteratur i form av handböcker för kriminaltekniker, föreläsningsanteckningar från Rättsmedicin för Jurister och sökningar på Internet ex. SKL’s hemsida. I arbetet har jag först gått igenom bakgrunden rent historiskt kring DNA, från första upptäckten av hur egenskaper ärvs 1865 till modern tid då DNA används som bevis i rättegångar. Resultatet har jag redovisat som ett fingerat ”case” där jag låtit huvudpersonerna agera utifrån vad man ska tänka på när man säkrar DNA-spår och låtit dem följa hela kedjan ända till analyssvar och sedermera en dom i tingsrätten. Eftersom DNA är ett mycket känsligt spår är det viktigt att det tillvaratas på rätt sätt för att det inte skall kontamineras (dvs. smittas av spårsäkrarens eget DNA) och även förstöras. Detta för att kunna säkra att rätt person döms för brottet.
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Leavitt, Markley Carl. "Bacteriophage T5 DNA polymerase relationships of DNA polymerases." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185335.
Full textAbstract:
T5 DNA polymerase, a highly processive single polypeptide enzyme, and PRD1 DNA polymerase, a protein-primed DNA polymerase, have been analyzed for their primary structural features. The amino acid sequence of T5 DNA polymerase reveals a high degree of homology with DNA polymerase I (Pol I) of Escherichia coli and retains many of the amino acid residues which have been implicated in the 3'-5' exonuclease and DNA polymerase activities of that enzyme. Alignment with sequences of polymerase I and T7 DNA polymerase (family A polymerases) was used to identify regions possibly involved in the high processivity of this enzyme. Further amino acid sequence comparisons of T5 DNA polymerase with a large group of DNA polymerases (family B) previously shown to exhibit little similarity to Pol I, indicate certain sequence segments are shared among distantly related DNA polymerases. These shared regions have been implicated in the 3'-5' exonuclease function of Pol I which suggests that the proofreading domains of all these enzymes may be related. Mutations in these segments in T5 DNA polymerase (family A) and PRD1 DNA polymerase (family B) greatly decrease the exonuclease activity of these enzymes but leave the polymerase activities intact. Additionally, an exonuclease deficient T5 DNA polymerase is used in DNA sequencing reactions and yields consistent results with low background contamination on autoradiographs of polyacrylamide/urea gels. PRD1 mutants defective in 3 regions which are highly conserved among family B DNA polymerases, are deficient in DNA polymerase activity but retain exonuclease activity.
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Carson, Christian Tyler. "DNA viruses and the cellular DNA repair machinery /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3175282.
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