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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

SSR= ökad säkerhet? : Fallstudie Kosovo

Rubinsson, Emma January 2008 (has links)
The security sector of a state is supposed to deliver a secure environment for its citizens. Security Sector Reform (SSR) are reforms aiming to develop the security sector of a state in order to guarantee human security. In Kosovo SSR is in operation to create a more secure society with greater civil control. The aim of this essay is to examine how Kosovos’ security sector is organized year 2007 and how its development should progress in order to facilitate security and civilian control of the security sector, with focus on three central actors: the Kosovo Police Service (KPS), the Kosovo Protection Corps (KPC) and the security service. The theoretical framework used, with a descriptive purpose, pinpoints Human security, Post- conflict reconstruction, Intrastate Security Dilemma, SSR and Implementation theory for networks as important elements for the study and understanding of SSR. The main findings are that a holistic approach is needed when addressing SSR and that all further SSR in Kosovo are dependent of the future status of Kosovo and a good economic development. Currently, one of the main problems facing the security sector in Kosovo is the lack of civil oversight. Key words: Security Sector Reform (SSR), human security, Kosovo, Kosovo Police Service (KPS), Kosovo Protection Corps (KPS), security service. Nyckelord: Säkerhetssektorreformer (SSR), mänsklig säkerhet, Kosovo, Kosovo Police Service (KPS), Kosovo Protection Corps (KPS), säkerhetstjänst.
102

Expression of defense genes in sorghum grain mold and tagging and mapping a sorghum anthracnose resistance gene

Katile, Seriba Ousmane 15 May 2009 (has links)
Sorghum grain mold and anthracnose are two major diseases of sorghum (Sorghum bicolor) that constrain sorghum production worldwide. Grain mold is caused by several species of fungi, but the two most common are Curvularia lunata and Fusarium thapsinum. Isolates of these two species were used to inoculate panicles of selected sorghum cultivars in green house and field experimentations. Panicles were sprayed at the time of anthesis with conidial suspensions of the two fungal species individually or in a mixture and with water to serve as a control. Samples were collected 48 hours after inoculation for RNA extraction. In greenhouse studies, four cultivars (Tx2911, Sureno, SC170 and RTx430) were used while thirteen cultivars were grown in the field experiments. Gene expression was measured for the following genes using real time polymerase chain reactions (rt-PCR): PR10, β-glucanase, chitinase, thaumatin, sormatin, phenyalanine ammonia lyase (PAL), obtusifoliol 14α-demethylase (Obtus), antifungal protein (AFP), apoptosis related protein (Apop) and leucine rich repeat (LRR). Seed germination tests in field grown cultivars indicated that germination rates for SC279-14E, SC660 and Sureno were not greatly influenced by grain mold. Covering the panicles with bags served to protect them against grain mold pathogens. The seed mycoflora test showed that Fusarium thapsinum was the most frequently recovered species and there were more species present in non-covered panicles. The response of sorghum cultivars to grain mold infection involves multiple defense genes. Real time PCR used to study the expression of sorghum defense in greenhouse grown plants showed that mRNA encoding PR-10, a small 10 kDa protein, was highly expressed in the glumes and spikelets of resistant cultivars Tx2911 and Sureno and constitutively in leaves. The expression of some other defense genes like beta-glucanase, chitinase and AFP was variable. Sormatin was not expressed. Expression of β-glucanase, chitinase, and PR10 was higher in field than in greenhouse experiments. A second area of research involved tagging of a resistance gene for sorghum anthracnose. Three AFLP markers (Xtxa607, Xtxa3181 and Xtxa4327) and three SSRs (Xtxp3, Xtxp55 and Xtxp72) were identified. These markers were loosely linked to the resistance genes. The markers are located on linkage group B. The results suggest that markers located 20-30 cM on one side or the other of those tested should provide useful tags for the resistance gene.
103

Diversity of Low Chill Peaches (Prunus persica) from Asia, Brazil, Europe and the USA

Anderson, Natalie A. 2010 May 1900 (has links)
One hundred fifty-five peach (Prunus persica) cultivars, from Asia, Brazil, Europe, and the USA, were examined using eleven Simple Sequence Repeats (SSRs) to study the genetic relationships among low chill as compared to high chill peach germplasm. Data was analyzed by NTSYSpc to form a similarity matrix using Nei and Li’s Dice similarity coefficient. This similarity matrix was then subjected to a cluster analysis and a dendrogram was constructed using the UPGMA (Unweighted Pair-Group Method, Arithmetic Mean) method. A wide range of diversity was detected, from 0.33 coefficient of similarity amongst the Thai peaches to 0.97 between two Brazilian peaches. The most distant clusters were the low chill peaches from Thailand and Taiwan and the local cultivars (both fruit and ornamental types) from China. Among the improved germplasm, there were distinct clusters for the Chinese/Japanese cultivars, three clusters for the Brazilian cultivars and one for the cultivars from the USA and Europe. The Brazilian materials clustered according to breeding programs in São Paulo and Pelotas reflecting the different sets of local cultivars used in the breeding efforts. The largest group investigated was the European/USA peaches. This group subdivided into three distinct clusters, with a general clustering of the low chill germplasm. The low chill accessions from Asia were genetically distant from the improved low chill peaches from the USA or Brazil. The low chill peaches from the Americas were more closely related to the high chill peaches developed in the USA and China/Japan due to the introgression of this germplasm into a low chill background.
104

Genetic Diversity Of Scald (rhynchosporium Secalis) Disease Resistant And Sensitive Turkish Barley Seed Sources As Determined With Simple Sequence Repeats

Dizkirici, Ayten 01 August 2006 (has links) (PDF)
Scald disease (Rhynchosporium secalis) is one of the major plant diseases causing considerable yield loss in barley (Hordeum vulgare) plantations in Turkey. To develop, scald resistant barley varieties, C.R.I.F.C. of Turkey has a large accumulated collection of barley seed sources in hand, but these samples are difficult to be followed and used in the breeding programs due to lack of genetic studies on them. Thus, the objective of this study was to characterize and fingerprint of eighty barley seed sources, and assess the magnitude and pattern of genetic diversity that could be used to have more efficient scald disease resistant breeding programs in the future. Forty scald disease resistant and 40 scald sensitive Turkish barley seed sources were screened using 6 simple sequence repeats (SSR) primers. Each of barley seed source were represented with four seeds, assuming they are genetically uniform since barley is a self-pollinated crop. Estimated genetic parameters indicated that scald disease resistant and sensitive barley seed sources still maintain large amount of genetic diversity. For example, expected heterozygosity was 0.62&plusmn / 0.01 and 0.64&plusmn / 0.01 for resistant and sensitive Turkish barley seed sources, respectively. Thirty-nine percent of total genetic variation was between populations for resistant and 46% for sensitive group, while 61% of total variation was within populations for resistant group and 54% for sensitive group. When overall Turkish barley seed sources were considered, genetic distances between scald sensitive seed source S18 and resistant R1 as well as between sensitive S28 and resistant R1 were large. Scald resistant and sensitive barley seed sources were generally located in different clusters in dendrogram. The presence of R25, R39 and S16 barley seed sources with high genetic diversity parameters among studied seed sources, suggests that this diversity could be important drive in future barley breeding program in Turkey. However, further study is needed to illustrate genetic divergence of Turkish barley seed sources with use of more molecular markers.
105

Expression of defense genes in sorghum grain mold and tagging and mapping a sorghum anthracnose resistance gene

Katile, Seriba Ousmane 10 October 2008 (has links)
Sorghum grain mold and anthracnose are two major diseases of sorghum (Sorghum bicolor) that constrain sorghum production worldwide. Grain mold is caused by several species of fungi, but the two most common are Curvularia lunata and Fusarium thapsinum. Isolates of these two species were used to inoculate panicles of selected sorghum cultivars in green house and field experimentations. Panicles were sprayed at the time of anthesis with conidial suspensions of the two fungal species individually or in a mixture and with water to serve as a control. Samples were collected 48 hours after inoculation for RNA extraction. In greenhouse studies, four cultivars (Tx2911, Sureno, SC170 and RTx430) were used while thirteen cultivars were grown in the field experiments. Gene expression was measured for the following genes using real time polymerase chain reactions (rt-PCR): PR10, β-glucanase, chitinase, thaumatin, sormatin, phenyalanine ammonia lyase (PAL), obtusifoliol 14α-demethylase (Obtus), antifungal protein (AFP), apoptosis related protein (Apop) and leucine rich repeat (LRR). Seed germination tests in field grown cultivars indicated that germination rates for SC279-14E, SC660 and Sureno were not greatly influenced by grain mold. Covering the panicles with bags served to protect them against grain mold pathogens. The seed mycoflora test showed that Fusarium thapsinum was the most frequently recovered species and there were more species present in non-covered panicles. The response of sorghum cultivars to grain mold infection involves multiple defense genes. Real time PCR used to study the expression of sorghum defense in greenhouse grown plants showed that mRNA encoding PR-10, a small 10 kDa protein, was highly expressed in the glumes and spikelets of resistant cultivars Tx2911 and Sureno and constitutively in leaves. The expression of some other defense genes like beta-glucanase, chitinase and AFP was variable. Sormatin was not expressed. Expression of β-glucanase, chitinase, and PR10 was higher in field than in greenhouse experiments. A second area of research involved tagging of a resistance gene for sorghum anthracnose. Three AFLP markers (Xtxa607, Xtxa3181 and Xtxa4327) and three SSRs (Xtxp3, Xtxp55 and Xtxp72) were identified. These markers were loosely linked to the resistance genes. The markers are located on linkage group B. The results suggest that markers located 20-30 cM on one side or the other of those tested should provide useful tags for the resistance gene.
106

SSR= ökad säkerhet? : Fallstudie Kosovo

Rubinsson, Emma January 2008 (has links)
<p>The security sector of a state is supposed to deliver a secure environment for its citizens. Security Sector Reform (SSR) are reforms aiming to develop the security sector of a state in order to guarantee human security. In Kosovo SSR is in operation to create a more secure society with greater civil control.</p><p>The aim of this essay is to examine how Kosovos’ security sector is organized year 2007 and how its development should progress in order to facilitate security and civilian control of the security sector, with focus on three central actors: the Kosovo Police Service (KPS), the Kosovo Protection Corps (KPC) and the security service. The theoretical framework used, with a descriptive purpose, pinpoints Human security, Post- conflict reconstruction, Intrastate Security Dilemma, SSR and Implementation theory for networks as important elements for the study and understanding of SSR.</p><p>The main findings are that a holistic approach is needed when addressing SSR and that all further SSR in Kosovo are dependent of the future status of Kosovo and a good economic development. Currently, one of the main problems facing the security sector in Kosovo is the lack of civil oversight.</p><p>Key words: Security Sector Reform (SSR), human security, Kosovo, Kosovo Police Service (KPS), Kosovo Protection Corps (KPS), security service.</p><p>Nyckelord: Säkerhetssektorreformer (SSR), mänsklig säkerhet, Kosovo, Kosovo Police Service (KPS), Kosovo Protection Corps (KPS), säkerhetstjänst.</p>
107

Power System Dynamics Enhancement Through Phase Unbalanced and Adaptive Control Schemes in Series FACTS devices

2012 April 1900 (has links)
This thesis presents novel series compensation schemes and adaptive control techniques to enhance power system dynamics through damping Subsynchronous Resonance (SSR) and low-frequency power oscillations: local and inter-area oscillations. Series capacitive compensation of transmission lines is used to improve power transfer capability of the transmission line and is economical compared to the addition of new lines. However, one of the impeding factors for the increased utilization of series capacitive compensation is the potential risk of SSR, where electrical energy is exchanged with turbine-generator shaft systems in a growing manner which can result in shaft damage. Furthermore, the fixed capacitor does not provide controllable reactance and does not aid in the low-frequency oscillations damping. The Flexible AC Transmission System (FACTS) controllers have the flexibility of controlling both real and reactive power which could provide an excellent capability for improving power system dynamics. Several studies have investigated the potential of using this capability in mitigating the low-frequency (electromechanical) as well as the subsynchronous resonance (SSR) oscillations. However, the practical implementations of FACTS devices are very limited due to their high cost. To address this issue, this thesis proposes a new series capacitive compensation concept capable of enhancing power system dynamics. The idea behind the concept is a series capacitive compensation which provides balanced compensation at the power frequency while it provides phase unbalance at other frequencies of oscillations. The compensation scheme is a combination of a single-phase Thyristor Controlled Series Capacitor (TCSC) or Static Synchronous Series Compensator (SSSC) and a fixed series capacitors in series in one phase of the compensated transmission line and fixed capacitors on the other two phases. The proposed scheme is economical compared to a full three-phase FACTS counterpart and improves reliability of the device by reducing number of switching components. The phase unbalance during transients reduces the coupling strength between the mechanical and the electrical system at asynchronous oscillations, thus suppressing the build-up of torsional stresses on the generator shaft systems. The SSR oscillations damping capability of the schemes is validated through detailed time-domain electromagnetic transient simulation studies on the IEEE first and second benchmark models. Furthermore, as the proposed schemes provide controllable reactance through TCSC or SSSC, the supplementary controllers can be implemented to damp low-frequency power oscillations as well. The low-frequency damping capability of the schemes is validated through detail time-domain electromagnetic transient simulation studies on two machines systems connected to a very large system and a three-area, six-machine power system. The simulation studies are carried out using commercially available electromagnetic transient simulation tools (EMTP-RV and PSCAD/EMTDC). An adaptive controller consisting of a robust on-line identifier, namely a robust Recursive Least Square (RLS), and a Pole-Shift (PS) controller is also proposed to provide optimal damping over a wide range of power system operations. The proposed identifier penalizes large estimated errors and smooth-out the change in parameters during large power system disturbances. The PS control is ideal for its robustness and stability conditions. The combination results in a computationally efficient estimator and a controller suitable for optimal control over wider range of operations of a non-linear system such as power system. The most important aspect of the controller is that it can be designed with an approximate linearized model of the complete power system, and does not need to be re-tuned after it is commissioned. The damping capability of such controller is demonstrated through detail studies on a three-area test system and on an IEEE 12-bus test system. Finally, the adaptive control algorithm is developed on a Digital Signal Processing Board, and the performance is experimentally tested using hardware-in-the-loop studies. For this purpose, a Real Time Digital Simulator (RTDS) is used, which is capable of simulating power system in real-time at 50 µs simulation time step. The RTDS facilitates the performance evaluation of a controller just like testing on a real power system. The experimental results match closely with the simulation results; which demonstrated the practical applicability of the adaptive controller in power systems. The proposed controller is computationally efficient and simple to implement in DSP hardware.
108

Application of molecular markers in selected breeding material and plant genetic resources of Lolium perenne L.

Liu, Siyang 12 May 2015 (has links)
No description available.
109

Diversidade e estrutura populacional do tubarão-raposa nos oceanos Atlântico e Índico utilizando marcadores genéticos moleculares

Morales, Millke Jasmine Arminini. January 2016 (has links)
Orientador: Fausto Foresti / Resumo: Populações de elasmobrânquios têm sofrido declínios severos nas últimas décadas devido à massiva pressão pesqueira. Com características de vida que tornam a espécie mais suscetível à pesca, o tubarão-raposa Alopias superciliosus está classificado atualmente como vulnerável na lista vermelha de espécies ameaçadas da IUCN. A espécie apresenta maturação sexual tardia e somente dois (raramente quatro) filhotes a cada gestação, que dura aproximadamente 12 meses. Estas características evidenciam a necessidade de sistemas de manejo pesqueiro adequados à estruturação populacional da espécie, que se apresenta como um instrumento fundamental para sua conservação. Com o advento de novas tecnologias atualmente é viável utilizar ferramentas moleculares para elucidar questões evolutivas e genético-populacionais em organismos não modelos, gerando informações que podem auxiliar na elaboração de planos de manejo. Tendo em vista à escassez de informações sobre a dinâmica populacional do tubarão-raposa, o presente estudo teve como objetivo o desenvolvimento e aplicação de marcadores moleculares em amostras de A. superciliosus provenientes de diferentes localidades dos oceanos Atlântico e Índico. Um total de 12 marcadores moleculares do tipo microssatélite, sendo 11 polimórficos e 1 monomórfico, foram identificados e, a partir desta identificação, primers espécie-específicos foram desenvolvidos e padronizados. Para acessar a diversidade genética e populacional de A. superciliosus foram genotipad... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
110

Modelagem espacial do fluxo de sementes de Jatobá (Hymenaea courbaril), através de marcadores moleculares, na paisagem fragmentada do Pontal do Paranapanema, SP. / Spatial modeling of the seed flow for Hymenaea courbaril with ssr, in a fragmented landscape at Pontal do Paranapanema, Brazil.

Renato Miazaki de Toledo 17 June 2005 (has links)
Intervenções conservacionistas baseadas em receitas generalistas e uniformes têm eficácia comprometida por serem incapazes de incorporar as particularidades de cada ecossistema e as diferentes características regionais da atividade humana. Este trabalho teve como objetivo desenvolver uma metodologia que incorporasse a avaliação espacial do fluxo gênico contemporâneo de plantas ao planejamento territorial de paisagens fragmentadas. Adotou-se o Jatobá (Hymenaea courbaril), espécie zoocórica, como espécie guarda-chuva. Localizada no Pontal do Paranapanema, a área amostral utilizada possui 49km2, que abrigam sete sub-populações de Jatobá e 1,32 km2 de remanescentes florestais divididos em 4 fragmentos. Executamos o censo de árvores adultas e amostragem regular de indivíduos juvenis. Amostrou-se 359 indivíduos, dos quais 75 foram considerados como adultos, todos foram georreferenciados por GPS e genotipados por SSR. Analisando-se três locos de DNA genômico e um de c-DNA, foram realizados 21.225 testes de maternidade, nos quais 62 plantas jovens tiveram suas mães identificadas. A distribuição das distâncias de dispersão de sementes verificada indica que o isolamento para recolonização entre sub-populações ocorre em distâncias superiores a 1600m. Foram localizados 13 fragmentos que permaneceriam em condição de isolamento, mesmo após a recuperação de todas as APPs. Recomenda-se a inclusão do aumento de conectividade destas manchas, bem como do reflorestamento de todas as APPs, na lista de prioridades do planejamento da conservação da biodiversidade desta região. / Conservationist interventions, based on general and uniform protocols, lose effectiveness by being incapable to incorporate the particularities of each ecosystem and the different regional patterns of the human activity. This research meant to develop a method that incorporates the spatial evaluation of the contemporary gene flow of plants to the territorial planning of fragmented landscape. We adopted Hymenaea courbaril as an umbrella species. Located in the Pontal of the Paranapanema (São Paulo State, Brazil), the study area has 49km2, that shelters seven subpopulations of Hymenaea courbaril with 1,32km2 are covered by forest that is separated in four patches. We censused adult trees and also regular seedlings and juveniles were regularly sampled. A total of 359 individuals were identified and georreferencered by GPS and genotyped by SSR. Analyzing 3 loci of genomic DNA and one of c-DNA, we applied a maternity test. 62 young plants had them mothers identified. The distribution of distances of seed dispersal indicates that the isolation for recolonization between subpopulations occurs in distances greater than 1600m, indicating that the connectivity in the studied landscape is very low for Hymenaea courbaril. 13 habitat patches were located in isolation condition, even after the recuperation of all the law-protected riparian-corridor areas. These results emphasized the increase of connectivity of these spots, as well as the restoration in the protected riparian areas, as some of the top priorities in the planning of the biological conservation of this region.

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