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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.
311

Adaptive transmission for block-fading channels

Nguyen, Dang Khoa January 2010 (has links)
Multipath propagation and mobility in wireless communication systems give rise to variations in the amplitude and phase of the transmitted signal, commonly referred to as fading. Many wireless applications are affected by slowly varying fading, where the channel is non-ergodic, leading to non-reliable transmission during bad channel realizations. These communication scenarios are well modeled by the block-fading channel, where the reliability is quantatively characterized by the outage probability. This thesis focuses on the analysis and design of adaptive transmission schemes to improve the outage performance of both single- and multiple-antenna transmission over the block-fading channel, especially for the cases where discrete input constellations are used. Firstly, a new lower bound on the outage probability of non-adaptive transmission is proposed, providing an efficient tool for evaluating the performance of non-adaptive transmission. The lower bound, together with its asymptotic analysis, is essential for efficiently designing the adaptive transmission schemes considered in the thesis. Secondly, new power allocation rules are derived to minimize the outage probability of fixed-rate transmission over block-fading channels. Asymptotic outage analysis for the resulting schemes is performed, revealing important system design criteria. Furthermore, the thesis proposes novel suboptimal power allocation rules, which enjoy low-complexity while suffering minimal losses as compared to the optimal solution. Thus, these schemes facilitate power adaptation in low-cost devices. Thirdly, the thesis considers incremental-redundancy automatic-repeat-request (INR-ARQ) strategies, which perform adaptive transmission based on receiver feedback. In particular, the thesis concentrates on multi-bit feedback, which has been shown to yield significant gains in performance compared to conventional single-bit ARQ schemes. The thesis proposes a new information-theoretic framework for multi-bit feedback INR-ARQ, whereby the receiver feeds back a quantized version of the accumulated mutual information. Within this framework, the thesis presents an asymptotic analysis which yields the large gains in outage performance offered by multi-bit feedback. Furthermore, the thesis proposes practical design rules, which further illustrates the benefits of multi-bit feedback in INR-ARQ systems. In short, the thesis studies the outage performance of transmission over block-fading channels. Outage analysis is performed for non-adaptive and adaptive transmission. Improvements for the existing adaptive schemes are also proposed, leading to either lower complexity requirements or better outage performance. Still, further research is needed to bring the benefits offered by adaptive transmission into practical systems. / Thesis (PhD)--University of South Australia, 2010
312

Adaptive transmission for block-fading channels

Nguyen, Dang Khoa January 2010 (has links)
Multipath propagation and mobility in wireless communication systems give rise to variations in the amplitude and phase of the transmitted signal, commonly referred to as fading. Many wireless applications are affected by slowly varying fading, where the channel is non-ergodic, leading to non-reliable transmission during bad channel realizations. These communication scenarios are well modeled by the block-fading channel, where the reliability is quantatively characterized by the outage probability. This thesis focuses on the analysis and design of adaptive transmission schemes to improve the outage performance of both single- and multiple-antenna transmission over the block-fading channel, especially for the cases where discrete input constellations are used. Firstly, a new lower bound on the outage probability of non-adaptive transmission is proposed, providing an efficient tool for evaluating the performance of non-adaptive transmission. The lower bound, together with its asymptotic analysis, is essential for efficiently designing the adaptive transmission schemes considered in the thesis. Secondly, new power allocation rules are derived to minimize the outage probability of fixed-rate transmission over block-fading channels. Asymptotic outage analysis for the resulting schemes is performed, revealing important system design criteria. Furthermore, the thesis proposes novel suboptimal power allocation rules, which enjoy low-complexity while suffering minimal losses as compared to the optimal solution. Thus, these schemes facilitate power adaptation in low-cost devices. Thirdly, the thesis considers incremental-redundancy automatic-repeat-request (INR-ARQ) strategies, which perform adaptive transmission based on receiver feedback. In particular, the thesis concentrates on multi-bit feedback, which has been shown to yield significant gains in performance compared to conventional single-bit ARQ schemes. The thesis proposes a new information-theoretic framework for multi-bit feedback INR-ARQ, whereby the receiver feeds back a quantized version of the accumulated mutual information. Within this framework, the thesis presents an asymptotic analysis which yields the large gains in outage performance offered by multi-bit feedback. Furthermore, the thesis proposes practical design rules, which further illustrates the benefits of multi-bit feedback in INR-ARQ systems. In short, the thesis studies the outage performance of transmission over block-fading channels. Outage analysis is performed for non-adaptive and adaptive transmission. Improvements for the existing adaptive schemes are also proposed, leading to either lower complexity requirements or better outage performance. Still, further research is needed to bring the benefits offered by adaptive transmission into practical systems. / Thesis (PhD)--University of South Australia, 2010
313

Investigating landscape change and ecological restoration: an integrated approach using historical ecology and GIS in Waterton Lakes National Park, Alberta

Levesque, Lisa Marie 02 September 2005 (has links)
This thesis examines landscape change from 1889 to the present within the foothills-parkland ecoregion of Waterton Lakes National Park (WLNP) in southwestern Alberta, Canada. Land cover dynamics are explored qualitatively and quantitatively using Geographical Information Systems and a combination of historical and contemporary data sources including: (1) Dominion Land Survey (DLS) transect records (1889), (2) repeat oblique photographs (1914 and 2004) and repeat aerial photography (1939 and 1999). Results indicate a consistent increase in woody vegetation cover, particularly aspen forest cover, within the foothills-parkland since 1889, largely at the expense of native grasslands. The primary drivers of these changes likely include: climatic influences, changes to the historical grazing regime, the suppression of natural fire cycles and the cessation of First Nations’ land management practices. This research illustrates the value of integrating multiple historical data sources for studying landscape change in the Canadian Rockies, and explores the implications of this change for ecological restoration in the foothills-parkland of WLNP.
314

Understanding repeat attendance in market research studies : reasons for regular participation and recruitment procedures

Van Zyl, Shalaine 01 1900 (has links)
This dissertation presents the findings of a qualitative study on understanding the motivating factors underlying repeat attendance in market research studies and the ways in which repeat attendance participants are recruited to take part in such studies. The study was approached from an interpretivist paradigm, employing the self-determination theory and the theory of self-concept maintenance. Purposive sampling was applied. The data was collected by conducting eight semi-structured interviews with participants who had taken part in numerous market research studies. Through thematic analysis, sub themes were identified from the data, combined into second-level themes and grouped into the following three overarching themes: (1) participation motivation; (2) honesty/dishonesty; and (3) recruitment procedures. It was found that participants were not only motivated by extrinsic motivators such as incentives, but that intrinsic motivators were also present. Furthermore, a level of dishonesty was also evident, not only among the participants, but among the recruiters as well. / Psychology / M.A. (Psychology with specialisation in Research Consultation)
315

Role of AMP-Activated Protein Kinase in Cancer Cell Survival under Matrix-Deprived Conditions

Saha, Manipa January 2015 (has links) (PDF)
Cancer progression is a multi-step process requiring cells to acquire specific properties that aid the neoplastic growth. One such property is the ability to survive in the absence of matrix-attachment, a critical necessity for cells to traverse in circulation and seed metastases. Therefore, understanding the signalling mechanisms that protect cells from undergoing death in matrix-deprived condition, termed as anoikis, is important. We have used two systems to study this, one involving experimental transformation model, and another involving cancer cell lines. In the in vitro transformation model system involving the serial introduction of oncogenes, the ability to survive in anchorage-independent condition and generate spheres/colonies was dependent on the presence of the Simian Virus Small T antigen, SV40 ST. We identified that the viral antigen mediates its effects, at least in part, by activating the master metabolic regulator and cellular stress kinase AMP-activated protein kinase (AMPK) leading to maintenance of energy homeostasis. Consistent with this, our lab has previously identified both activation of AMPK upon matrix-deprivation in breast cells, as well as its requirement for survival under these conditions. However, a pathway often associated with survival under matrix-deprivation is the PI3K/Akt pathway. Surprisingly, we observed an AMPK-dependent decrease in Akt activity under conditions of matrix-detachment. Since this was contrary to the general notion, we probed deeper into a possible crosstalk between these two kinases. Our work revealed that AMPK activation in suspension inhibits Akt via upregulation of a known Akt phosphatase, pleckstrin homology domain leucinrich repeat protein phosphatise (PHLPP). We further show that the AMPK-PHLPP-Akt signalling axis is important for anoikis-resistance and metastasis. In addition, our results point to a yet unidentified protumorigenic role of PHLPP in breast cancer progression. With an aim to identify cellular proteins differentially regulated upon AMPK activation in breast cancer cells, we undertook a proteomics approach. Using 2-dimensional gel electrophoresis followed by mass spectrometric analysis, we identified some candidate proteins. We have validated the increase in levels of one of these proteins, annexin A2, in cancer cells upon AMPK activation. In summary, the present study unveils novel oncogenic functions of AMPK in cancer cells under the stress of matrix-deprivation. Furthermore, our results elucidate a double-negative feedback loop between two critical cellular kinases AMPK and Akt, and also identify a novel pro-tumorigenic role of PHLPP in breast cancer. In addition, we identify PHLPP and annexin A2 as novel proteins upregulated by AMPK in cancer cells. Thus, our results begin to identify pathways utilised by cancer cells to aid anchorage-independent growth, a critical step for cancer metastasis. Based on our results, inhibition of AMPK or perturbation of signalling axes involving AMPK, and PHLPP or annexin A2 might be considered as novel therapeutic approaches to combat cancer progression
316

Perda de gestação e incidência de fêmeas repetidoras de estro em rebanho leiteiro mestiço

Souza, Fransérgio Rocha de 17 December 2012 (has links)
The objective of the studies was evaluate the effects of the animal category, season of calving, season of artificial insemination (AI), parity, numbers of previous inseminated and days in milk (DIM) at AI on pregnancy losses (PL) and the incidence of pregnancy loss before and after 60th day post-AI from females repeat breeders (FRB) and the effects of the animal category, season of calving, parturition condition and parity on the incidence of FRB. Data from Study 1 were collected from 462 pregnancies and calving of lactating dairy cows and from 118 pregnancies of heifers and the Study 2 from 997 pregnancies and calving of lactating dairy cows and from 371 pregnancies of heifers. Pregnancy check was performed by ultrasound between days 28 and 44 post-AI and re-checked between days 45 and 60 post-AI. The rates of pregnancy loss before 60th day and the incidence of RB were higher in lactating dairy cows than heifers (11.90% vs. 3.4%, P=0.01 and 24.5% vs. 6.5%, P<0.001, respectively) and pregnancy loss after day 60 was not affected by animal category (P=0.58). The season of calving affected the pregnancy loss before 60th day (which was higher in spring/summer) and there was only tendency (P=0.078) in affecting the incidence of RB cows probably due to the worst postpartum recovery. There was no relationship between season of AI, parity, number of previous inseminated and DIM at IA and pregnancy loss before and after 60th day in lactating dairy cows. The parturition condition had no effects on RB incidence, however, the effect of parity was detected. Even in crossbred lactating dairy cows the incidence of overall pregnancy loss and RB condition was higher and could be considered as a factor that compromised the reproduction efficiency. / Objetivou-se com este estudo avaliar os efeitos da categoria animal, estação do parto, estação da inseminação artificial (IA), ordem de lactação, número de inseminações prévias e dias em lactação (DEL) na IA sobre as perdas de gestação (PG) e a incidência de PG antes e após 60 dias da IA de fêmeas repetidoras de estro (FRE), bem como os efeitos da categoria animal, estação do parto, tipo de parto e ordem de lactação na incidência de FRE. Os dados do experimento 1 foram coletados de 462 gestações e partos de vacas leiteiras em lactação e de 118 gestações de novilhas, e do experimento 2 de 997 gestações e partos de vacas leiteiras em lactação e 371 gestações de novilhas. O diagnóstico de gestação foi realizado por ultrassonografia entre os dias 28 e 44 pós-IA e a confirmação entre 45 e 60 dias pós-IA. As taxas de PG antes do 60º dia e a incidência de FRE foram maiores em vacas leiteiras lactantes que em novilhas (11,90% vs. 3,4%; P=0,01 e 24,5% vs. 6,5%; P<0,001, respectivamente), e a perda após 60 dias não foi afetada pela categoria animal (P=0,58). A estação do parto afetou a perda antes do 60º dia (que foi maior na primavera/verão) e houve apenas uma tendência (P=0,078) em afetar a incidência de vacas RE, provavelmente devido à pior recuperação no pós-parto. Não houve relação entre estação da IA, ordem de lactação, número de inseminações prévias e DEL na inseminação e PG antes e depois do 60º dia em vacas leiteiras lactantes. O tipo de parto não afetou a incidência de FRE, porém, o efeito da ordem de lactação foi detectado. Até mesmo em vacas leiteiras mestiças a incidência de perda geral de gestação e de FRE foi alta e pode-se considerá-los como problemas reprodutivos que comprometem a eficiência reprodutiva. / Mestre em Ciências Veterinárias
317

Caracterização química e molecular de quatro espécies de Vitex (Lamiaceae) e bioatividade contra o ácaro-da-necrose-do-coqueiro Aceria guerreronis (Acari : Eriophyidae)

Barreto, Ighor Costa 03 March 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Aceria guerreronis keifer is one of the main coconut pests in Brazil, its attack causes a premature fall, reduction of fruit size, water weight and volume, as well as stetic esthetic damages (necrosis) depreciating the product. Currently, there are five pesticides registered for the control of the coconut-necrotic mite. However, there is no specificity to A. guerreronis. The Lamiaceae family stands out with some specimens with notable insecticidal activity, among them the Vitex genus, known to have ecdysteroids and iridoids as markers of the genus. However, there is a shortage of specific chemotaxonomic studies for volatile compounds. The objective of this work was to identify the volatile compounds present in the essential oils of the species of Vitex gardneriana Schauer, Vitex capitata Vahl., Vitex rufescens A. Juss., Vitex megapotamica (Spreng.) Moldenk and to evaluate possible effects of toxicity and repellence against A. guerreronis. In addition to analyzing the genetic diversity of species of the genus Vitex using ISSR markers, verifying the occurrence of statistical correlations between the genetic diversity and the chemical profiles of the essential oils. Chromatographic and spectroscopic techniques (GC-MS / FID) were used for the detection of volatile compounds, and the molecular markers of ISSR for the genetic characterization of the species, as well as toxicity and repellency tests against necrotic necrosis. The results showed 46, 45, 41 and 37 constituents for V. capitata, V. megapotamica, V. gardneriana and V. rufences respectively, among which, -copaene, (E)-caryophyllene, -elemene, -humulene, trans-cadine-1(6)4-diene, viridiflorene and -cadinene were the main components of V. capitata and V. megapotamica. 6,9-guaiadiene, caryophyllene oxide, L-calamenene for V. gardneriana and (E)-cariophylene, ledol, germacrene D, -humulene, allo-aromadendrene, viridiflorene and -elemene for V. rufences. The results of molecular markers of ISSR generated a total of 90 fragments, of which 100% were polymorphic. The genotypes of the four Vitex species selected for this study were pooled using the Jaccard coefficient (JC). The mean similarity was 0.21 JC (0.08-0.45 JC). A clear separation of two groups was observed, with V. gardneriana being the most isolated of the four species, and V. capitata and V. megapotamica more closely related to each other. The acaricide activity of the four oils was also evaluated by means of toxicity and repellency tests against A. guerreronis. The essential oil of V. gardneriana showed acaricidal activity against A. guerreronis with a LC50 of 0.85 mg.mL-1, whereas the oils of V. capitata, V. megapotamica and V. rufecens were not toxic to this pest up to 2.3 mg. Ml-1 when tested through the toxicity bioassay. In general, essential oils distilled from the Vitex species repelled A. guerreronis after 24 hours at a concentration of 1.8 mg.mL-1 using abamectin as a control in the two-choice disc repellency assay, however, the essential oil of V. gardneriana presented a statistically significant acaricidal activity against the coconut mite necrosis. Introducing himself as a potential candidate for the development of an acaricide product. / O ácaro-da-necrose-de-coqueiro Aceria guerreronis keifer é uma das principais pragas de coqueiro do Brasil, seu ataque causa queda prematura, redução no tamanho e peso dos frutos e volume de água, além dos danos estéticos (necroses) na casca que diminui o valor comercial do produto. Atualmente, existem cinco agrotóxicos registrados para o controle dessa praga. No entanto, não há especificidade ao A. guerreronis. A família Lamiaceae se destaca com alguns exemplares com notória atividade inseticida, dentre eles, o gênero Vitex, conhecido por possuir dentre seus constituintes os ecdisteroides e iridoides como marcadores do gênero, todavia, há uma escassez de estudo quimiotaxonômicos específicos para compostos voláteis. O objetivo deste trabalho foi identificar os compostos voláteis presentes nos óleos essenciais das espécies de Vitex gardneriana Schauer, Vitex capitata Vahl., Vitex rufescens A. Juss., Vitex megapotamica (Spreng.) Moldenk e avaliar possíveis efeitos de toxicidade e repelência frente ao A. guerreronis, além de analisar a diversidade genética de espécies do gênero Vitex. Técnicas cromatográficas e espectroscópicas (CG-MS/FID) foram utilizadas para detecção dos compostos voláteis, e os marcadores moleculares de ISSR foram empregados para a caracterização genética das espécies, além de testes de toxicidade e repelência contra ao àcaro-da-necrose. Os resultados mostraram 46, 45, 41 e 37 constituintes para V. capitata, V. megapotamica, V. gardneriana e V. rufences respectivamente, dentre os quais, -copaeno, (E)-cariofileno, -elemeno, -humuleno, trans-cadina-1(6),4-dieno, viridiflorene e -cadineno foram os principais componentes de V. capitata e V. megapotamica. 6,9- guaiadieno, óxido de cariofileno, L-calameneno para V. gardneriana e (E)-cariofileno, ledol, germacreno D, -humuleno, allo-aromadendreno, viridifloreno e -elemene para V. rufences. Os resultados dos marcadores moleculares de ISSR geraram um total de 90 fragmentos, dos quais 100% foram polimórficos. Os genótipos das quatro espécies de Vitex selecionadas para este estudo foram agrupados utilizando o coeficiente Jaccard (JC). A média de similaridade foi de 0,21 JC (0,08-0,45 JC). Observou-se uma clara separação de dois grupos, sendo V. gardneriana a mais isolada das quatro espécies, e V. capitata e V. megapotamica mais próxima geneticamente entre si. A atividade acaricida dos quatro óleos também foi avaliada por meio de ensaios de toxicidade e repelência contra o àcaro-da-necrose. O óleo essencial de V. gardneriana mostrou atividade acaricida ao A. guerreronis com uma CL50 de 0,85 mg.mL-1, enquanto que os óleos de V. capitata, V. megapotamica e V. rufecens não foram tóxicos para esta praga até 2,3 mg.ml-1, quando testados através do bioensaio de toxicidade. Em geral, os óleos essenciais destilados a partir das espécies de Vitex repeliram o A. guerreronis após 24 horas a uma concentração de 1.8 mg.mL-1 utilizando abamectina como controle no ensaio de repelência disco de duas escolha, no entanto, o óleo essencial de V. gardneriana apresentou atividade acaricida estatisticamente significativa frente ao ácaro-da-necrose-do-coqueiro. Apresentando-se como potencial candidato para o desenvolvimento de um produto acaricida. / São Cristóvão, SE
318

Frontotemporal lobar degeneration in Finland:molecular genetics and clinical aspects

Kaivorinne, A.-L. (Anna-Lotta) 20 November 2012 (has links)
Abstract Frontotemporal lobar degeneration (FTLD) is the second most common neurodegenerative disease leading to early-onset dementia (&#60;&#160;65 years), next to Alzheimer’s disease. FTLD is substantially a genetic disorder with up to 50% of cases having a positive family history. Mutations in the genes microtubule-associated protein tau (MAPT) and progranulin (PGRN) account for about 10–20% of all cases of FTLD. Hexanucleotide repeat expansion mutation within the gene C9ORF72 has recently been identified as the major cause of FTLD, FTLD with amyotrophic lateral sclerosis (ALS) and pure ALS. During this study, hexanucleotide repeat expansion within the C9ORF72 gene was shown to explain nearly 50% of familial and 30% of all FTLD cases in the Finnish population. Otherwise, the genetic background of Finnish FTLD is largely unknown. The object of the present work was to disentangle the genetic aetiology of FTLD in the Finnish population. We studied a cohort of patients with a clinical diagnosis of FTLD from the province of Northern Ostrobothnia, Finland. Sequencing analysis of the genes MAPT, charged multi-vesicular body protein 2B (CHMP2B) and TAR DNA binding protein (TARDBP) were performed and the MAPT haplotypes were analysed. Correlations between genotype and phenotype were studied in patients with C9ORF72 repeat expansion mutation. C9ORF72 expansion mutation explained nearly 30% of cases of FTLD in our cohort. Concomitant ALS and positive family history of the disease increased the possibility of carrying expanded C9ORF72. The clinical phenotype of C9ORF72 expansion carriers varied at presentation: both behavioural and language variants were detected with or without ALS. The behavioural presentations included prominent psychotic features, although psychiatric presentations were not overrepresented in expansion carriers. No pathogenic mutations were identified in the MAPT, CHMP2B and TARDBP genes in our series of FTLD patients. The H2 MAPT haplotype was associated with FTLD in the series. Our findings emphasise the importance of C9ORF72 expansion mutation in FTLD. While mutations in MAPT and PGRN cause a significant proportion of cases of FTLD worldwide, they seem to be rare causes of FTLD in the Finnish population. Besides being infrequent in other populations, mutations in CHMP2B and TARDBP are rare causes of FTLD in the Finnish population as well. Our findings have clinical implications for recognising phenotypic features characteristic of expanded C9ORF72 as well as for genetic counselling of Finnish patients with FTLD. Even though a considerable proportion of our cases of familial FTLD is caused by the C9ORF72 expansion, over 50&#160;% of our familial cases are without a molecular genetic diagnosis, suggesting that there are other unidentified causal genes to be found. / Tiivistelmä Otsa-ohimolohkorappeumat on toiseksi yleisin työikäisten dementiaa aiheuttava etenevä aivojen rappeumasairaus. Toisinaan otsa-ohimolohkorappeumat esiintyvät yhdessä liikehermorappeuman, amyotrofisen lateraaliskleroosin (ALS), kanssa. Perinnöllisillä tekijöillä on todennäköisesti keskeinen merkitys taudin taustalla. Mutaatiot microtubule-associated protein tau (MAPT)- ja progranulin (PGRN) geeneissä aiheuttavat yhteensä 10–20&#160;% otsa-ohimolohkorappeumista maailmalla. C9ORF72-geenissä sijaitsevan toistojaksomonistuman on vastikään todettu olevan yleisin otsa-ohimolohkorappeumia ja ALS:a aiheuttava mutaatio. Mutaatio on erityisen yleinen suomalaisessa väestössä selittäen lähes 50&#160;% suvuittaisista ja 30&#160;% kaikista otsa-ohimolohkorappeumista. Oireyhtymän perinnöllisyys on muutoin huonosti tunnettu suomalaisessa väestössä. Tutkimuksen tavoitteena oli selvittää otsa-ohimolohkorappeumien geneettisiä syitä aineistossa, joka koostui vuosina 1999–2010 Oulun yliopistollisessa sairaalassa tutkituista potilaista. Tutkimuksessa selvitettiin MAPT-, charged multi-vesicular body protein 2B (CHMP2B)- ja TAR DNA-binding protein (TARDBP) geenien mutaatioiden esiintyvyyttä ja määritettiin MAPT-geenin haplotyypit. Lisäksi tutkittiin taudin kliinisiä erityispiirteitä C9ORF72-mutaation kantajilla. C9ORF72-mutaatio selitti lähes 30&#160;% otsa-ohimolohkorappeumista aineistossamme. Tutkimuksessa havaittiin, että suvuittain esiintyvä tautimuoto ja ALS yhdistyneenä otsa-ohimolohkorappeumaan liittyivät merkittävästi C9ORF72-mutaatioon. Monistuman kantajien fenotyyppi oli moninainen – ensioireina oli sekä käytösongelmia että kielellisiä vaikeuksia. Vaikka C9ORF72-mutaation kantajilla on kuvattu runsaasti psykoottisia oireita, psykoottiset oireet eivät olleet selvästi yliedustettuna mutaation kantajilla aineistossamme. Tutkimuksessa ei löydetty tautia aiheuttavia mutaatioita MAPT-, CHMP2B- tai TARDBP-geeneistä. Havaitsimme kuitenkin tilastollisesti merkittävän yhteyden MAPT-geenin H2-haplotyypin ja otsa-ohimolohkorappeumien välillä. Tuloksemme antavat uutta tietoa C9ORF72-mutaation kantajien kliinisistä erityispiirteistä. MAPT-geenin mutaatioiden merkitys otsa-ohimolohkorappeumien synnyssä ei näyttäisi olevan suomalaisessa väestössä niin merkittävä kuin muissa väestöissä. CHMP2B- ja TARDBP-mutaatiot ovat harvinainen oireyhtymän syy myös suomalaisessa väestössä. Tuloksiamme voidaan hyödyntää suomalaisten otsa-ohimolohkorappeumapotilaiden perinnöllisessä neuvonnassa. Huomattavista edistysaskelista huolimatta yli puolet suvuittain esiintyvistä tautitapauksistamme on vailla geneettistä diagnoosia, mikä antaa aihetta jatkotutkimuksille.
319

Coastal erosion on Högklint, Gotland: Processes, rate, and future implications / Kusterosion på Högklint, Gotland: Processer, hastighet och framtida konsekvenser

Glansholm, Helena January 2015 (has links)
The coastline along Högklint and Gråberget, Gotland, Sweden, was examined in order to establish therate of cliff erosion, erosion patterns, as well as some of the driving factors of the erosional processes in the area. Picture comparisons of the coastline reveal some major geomorphological changes in the area over the last 100 years, and the coast is still changing. At present, gardens are slowly disappearing over the cliff edge, and during storms Buske fishing place is threatened to be destroyed.Cliff retreat values could be obtained on two locations with the help of a Light Detection and Ranging (LiDAR) system. Scans were made with the LiDAR in January and May 2013. The scans were latercompared in CloudCompare and a mean erosion rate of 0.159 m/a was obtained for the Högklint siteand 0.123 m/a for the Gråberget site. The cliffs were also studied with a Schmidt hammer that clearly showed how that the cliff face was more eroded below the visible groundwater table than above it. With Gemini Tinytag data loggers temperatures were measured from October 2012 to May 2013 at the surface of the cliff face and inside the cliff at a depth of 4.5 cm and 9.5 cm. It could be concluded that tempera- tures were within the frost-cracking window (-10 to -3 ºC) for 19.7 Julian days, not consecutive. Due to the visibly high water content in the cliff and temperatures within the frost-cracking window, ice segre- gation within the cliff is a possible eroding factor in the area.The cliffs are subjected to erosion caused by ground-, melt-, and rainwater in a significant degree, possibly even more so than by the impact of breaking waves. It is important that the municipality ofGotland takes action to prevent further damage on personal property and to prevent personal injury. Todo this further studies needs to be done on how future climate change will effect the coast and rate oferosion. / Kuststräckan längs med Högklint och Gråberget, Gotland, Sverige, undersöktes för att etablera erosionshastighet,erosionsmönster och de drivande erosionsprocesserna i området. Genom återfotografering ochbildjämförelse av kuststräckan konstateras stora geomorfologiska förändringar de senaste 100 åren.Kustförändringarna är en pågående process. I dagsläget försvinner trädgårdar bit för bit över klintkantenoch vid varje storm hotas Buske fiskeläge att förstöras.Med en Light Detection and Ranging (LiDAR) radar erhölls data över hur mycket som försvunnitfrån klinten på två platser längs området. LiDAR- skanningarna gjordes i januari och maj 2013. Mätningarnajämfördes sedan i CloudCompare och visade på ett medelvärde av erosionshastigheten på0,159 m/a för platsen vid Högklint och 0,123 m/a för platsen vid Gråberget. Klintarna undersöktes ocksåmed en Schmidt-hammare. Resultatet visar hur klippväggen är mer eroderad under den synliga grundvattennivånän över den. Mellan oktober 2012 och maj 2013 mättes temperaturen på klintväggen, samt4,5 cm och 9,5 cm inne i berget, med hjälp av Gimini Tinytag datainsamlare. Resultatet visar att temperaturenlåg inom spannet för frostsprängning, dvs -10 till -3 ºC, i sammanlagt 19,7 dygn. Dessa lågatemperaturer tillsammans med den höga andelen synligt vatten i klinten möjliggör för bildandet avsegregationsis inne i klinten. Detta kan vara en bidragande orsak till uppluckring av klintväggen ocherosion i området.En betydande del av klinterosionen längs med kusten sker på grund av grund-, smält-, och regnvatten,kanske till och med i högre grad än brytande vågor. Det är viktigt att Gotlands kommun vidtar åtgärderför att förhindra skada på egendom och personskador. Mer studier behövs för att ta reda på hur framtidaklimatförändringar kommer att påverka klintarna och erosionshastigheten längs med kusten.
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Characterisation of eight non-codis Ministrs in four South African populations to aid the analysis of degraded DNA

Ismail, Aneesah January 2009 (has links)
Magister Scientiae - MSc / In many forensic cases, such as mass disasters reconstruction cases, the recovered DNA is highly degraded. In such incidences, typing of STR loci has become one of the most powerful tools for retrieving information from the degraded DNA. However, as DNA degradation proceeds, three phenomena occur consecutively: loci imbalance, allele dropout and no amplification. To solve the problem of degraded DNA, redesigned primer sets have been developed in which the primers were positioned as close as possible to the STR repeat region. These reduced primer sets were called Miniplexes. Unfortunately, a few of the CODIS STR loci cannot be made into smaller amplicons. For this reason non-CODIS miniSTRs have been developed. The present study was undertaken for the population genetic analysis of microsatellite variation in four South African populations; Afrikaner, Xhosa, Mixed Ancestry and Asian Indian using eight non-CODIS miniSTR loci. These miniSTRs loci were characterized within the populations by estimating the levels of diversity of the markers, estimating the population genetic parameters, and studying the inter-population relationships. All of the miniSTRs were amplified successfully and the genetic variability parameters across all loci in Afrikaner, Mixed Ancestry, Asian Indian and Xhosa were estimated to be in the range of 3 (D4S2364) to 12 (D9S2157) alleles, the total number of alleles over all loci ranged from 100 to 204, the allelic richness ranged from 3.612 to 10.307 and the heterozygosity ranged from 0.4360 to 0.8073. Genetic distance was least between Afrikaner and Asian Indian and highest between Xhosa and Mixed Ancestry. Deviations from Hardy-Weinberg equilibrium were not observed for most of the loci. The low mean FIS (-0.027) and FIT (-0.010) and FST (0.017) values across the populations indicated low level of inbreeding within (FIS) and among (FST) the populations. The Asian Indian population showed higher levels of the inbreeding coefficient, indicating less gene exchange between it and other populations. These 8 markers can be used for genetic investigations and assessing population structure. The study contributed to the knowledge and genetic characterization of four South African populations. In addition, these MiniSTRs prove to be useful in cases where more genetic information is needed. / South Africa

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