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Nominal record linkage : the development of computer strategies to achieve the family-based record linkage of nineteenth century demographic dataWelford, John Anthony January 1989 (has links)
This thesis was originally submitted for examination in March 1983. Following the result of the viva in October of that year an appeal was lodged, and the subsequent proceedings lasted for almost four years. In October 1987 formal notification was made that the thesis could be revised and resubmitted. The prolonged length of the appeal proceedings has meant that the computing environment within which the research was set has developed significantly from the position in 1983. Indeed, in purely practical terms, the computing systems which were used at that time are no longer operational. The opportunity for making modifications and refinements to the record linkage system, and for incorporating additional primary source materials (even were sufficient human resources available), has therefore been removed. Under these circumstances, the record linkage strategies described in the revised thesis are precisely the same as those presented in the 1983 submission. For this reason and because of the extensive delays in carrying out the appeal proceedings it has not seemed appropriate to provide a full review of developments in the record linkage field beyond this date. Reference has, however, been made to the subsequent, crucial impact of the findings of the present research on the progress of the later phases of the 1851 Census National Sample Project, which I co-directed with Professor Michael Anderson at the University of Edinburgh. The entire conceptual and strategic approach to the organisation of family information in this project grew directly from perceptions which were central to the present research. Reference has also been made to the influence of the present research on the development of the SASPAC package, a computing system for handling the 1981 Population Census Small Area Statistics data for Great Britain. I was the chief systems designer of SASPAC, and the design and implementation methods which were adopted in this development drew heavily on the experience gained from the present research. Finally, the opportunity has been taken (in the new Section 10.2), to present the findings of some fresh analyses of 1851 household census data which serve to confirm the validity of the linkage strategies which have been developed.
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Isolation and characterization of microsatellite markers in the house sparrow (Passer domesticus L.)Neumann, Karsten January 1996 (has links)
No description available.
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Paleoekologické aspekty evoluce ústřic rodu Rhynchostreon Bayle / Palaeoecological aspects of Rhynchostreon Bayle oyster evolutionRantuch, Jakub January 2014 (has links)
This paper presents a multilevel analysis of palaeoecological aspects of the process of the Rhynchostreon genera evolution. According to the latest results of research, the process of genus appears to be more dynamic than previously assumed.The processes of internal dynamics of the environment in conjuncture with other studied aspects of the late cretaceous environment (e.g. paleotemperature, salinity, etc.) were a significant factor that initiated the activity of selective pressure and represents an important factor in group evolution. In this work we provide the overall hypothesis about co-evolution of two intrageneric (sisters) lineages in Rhynchostreon genera. The definiton of evolutionary trends of intrageneric lineages within the presented hypothesis (including a new description of oyster species) is supported by various analytical methods, which anchors them in the current zoological nomenclature system. An electron microscopy, isotopes and biometrical analysis of a shell in cooperation with some of the sedimentologic methods suggest a relation of lithology (as a result of environmental aspect) and evolution process. The transregional concept of proposed ecological-evolutionary models, based on materials studies from various paleogeographic regions of cretaceous world, increases the...
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Prédiction et modélisation du risque dans le cancer de l'endomètre de stade précoce / Risk prediction and modeling in early stage endometrial cancerBendifallah, Sofiane 16 September 2016 (has links)
Le développement de nouvelles options thérapeutiques est à l’origine d’un changement de paradigme dans le processus de décision médicale. L'émergence de la médecine individualisée et la complexité croissante des données médicales ont conduit à l'avènement des modèles de prédiction. Pour le cancer de l'endomètre, ces modèles (algorithmes, scores et nomogrammes) ont été développés pour stratifier, estimer et prédire le risque de métastase ganglionnaire et de récidive. Le principal enjeu clinique est d’intégrer ces outils en vu d’optimiser les stratégies de prévention, de diagnostic et de traitement. Nous nous sommes intéressés au risque de récidive et d’envahissement ganglionnaire sur la base d’une analyse en population, puis individuelle. À l’échelle de la population, nous avons proposé : i) un travail de comparaison des principales classifications internationales, ii) une nouvelle classification clinicopathologique reposant sur l’incorporation d’un prédicteur histologique, iii) le développement de scores de stratification du risque. À l’échelle individuelle, nous avons développé : i) une méthodologie de validation externe des modèles prédictifs, point de départ indispensable à leur utilisation en pratique, ii) un nomogramme clinicopathologique spécifique d’envahissement ganglionnaire et son seuil de décision clinique. La modélisation mathématique en cancérologie est susceptible de transformer notre façon d’appréhender les stratégies préventives et curatives dans le cancer de l’endomètre. Les pistes d’optimisation sont multiples et laissent entrevoir la possibilité, dans un avenir proche, d’une application clinique à ces outils. / With the abundance of new options in diagnostic and treatment modalities, a shift in the medical decision process for endometrial cancer has been observed. The emergence of individualized medicine and the increasing complexity of available medical data have lead to the development of prediction models. In endometrial cancer, those clinical models (algorithms, nomograms, and risk scoring systems) have been reported, for stratifying and subgrouping patients, with various unanswered questions regarding such things as the optimal surgical staging for lymph node metastasis as well as the assessment of recurrence and survival outcomes. Through this manuscript we developed the question of the risk stratification for recurrence at the population level and the probability of lymph node involvement estimation at an individual level in early stage endometrial cancer. This double approach was adopted with the aim to illustrate the interest of these tools in clinical practice. At the population level, we proposed: i) a comparison of the main international clinicopathological classifications ii) a new clinicopathological classification based on a pathological predictor iii) two risk stratification systems for recurrence and lymph node metastasis. At the individual level we developed: i) a reproducible methodology for external validation of predictive models, ii) a specific clinic pathological nomogram for lymph node metastasis. In the future, the emerging field of molecular or biochemical markers research may substantially improve the predictive approach for preventive and curative strategies in endometrial cancer.
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Evolução geomorfológica e tectônica da porção norte da Bacia do Amazonas : região do Rio Apuaú (AM) /Nascimento, Mayara Aline Santos Ribeiro do January 2016 (has links)
Orientador: Norberto Morales / Resumo: A paisagem na Amazônia tem mostrado um quadro geomorfológico evolutivo associado a condicionamentos tectônicos no controle da rede de drenagem, com importantes mudanças nos cursos dos rios associadas a sistemas de falhas no âmbito da Neotectônica. Esta pesquisa compreende o estudo da bacia hidrográfica do rio Apuaú, afluente da margem esquerda do rio Negro na sua porção média, a norte de Manaus, no Estado do Amazonas. Foi subsidiada por estudos estruturais e geomorfológicos apoiados em dados de campo, de sensores remotos e de datação dos depósitos aluvionares. Foram reconhecidos blocos desnivelados do relevo, com rupturas de declive (knickpoints) associadas e controladas por falhas. A rede de drenagem apresenta padrões anômalos dos cursos d’água, capturas, meandros e canais encurvados, alinhamento de canais retilíneos, marcando zonas de juntasou zonas de falhas. Os blocos controlam também a distribuição de terraços, paleoterraços e canais abandonados, e suas datações por LOE apontam para depósitos mais antigos na faixa de 53.000 a 62.200 anos, intermediários na faixa de 20.330 a 23.100 anos, e depósitos atuais. O quadro geológico-estrutural aponta para compartimentos morfotectônicos, controlados por falhas normais e falhas transcorrentes destrais associadas. As falhas normais condicionam blocos rotacionados, a rede de drenagem e a distribuição dos depósitos aluvionares, enquanto as falhas transcorrentes parecem balizar e controlar os blocos na porção norte e leste da bacia hi... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
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Απομόνωση μικροδορυφόρων από το δάκο της ελιάς, Bactrocera oleae και χρησιμοποίησή τους για την ανάλυση φυσικών πληθυσμών του είδους / Icrosatellite isolation of the olive fly, Bactrocera oleae and their use for the analysis of natural populations of the speciesΑυγουστίνος, Αντώνιος 24 June 2007 (has links)
Ο δάκος της ελιάς, Bactrocera oleae, αποτελεί το κυριότερο παράσιτο του καρπού της ελιάς. Λόγω της μεγάλης οικονομικής σημασίας της ελιάς, ιδιαίτερα για τις Μεσογειακές χώρες, ο αποτελεσματικότερος έλεγχος του εντόμου αυτού είναι απαραίτητος. Η εφαρμογή μεθόδων ολοκληρωμένης διαχείρισης του παρασίτου αυτού, μεθόδων δηλαδή φιλικών προς το περιβάλλον, επιβάλλει την καλύτερη γνώση της βιολογίας του και ιδιαίτερα της γενετικής και της γενετικής δομής των φυσικών πληθυσμών του. Στα πλαίσια αυτά, στόχος της παρούσας μελέτης ήταν η ανάπτυξη στο δάκο DNA δεικτών, των μικροδορυφόρων, οι οποίοι είναι άφθονοι στα γονιδιώματα και επιπλέον υψηλά πολυμορφικοί, για την ανάλυση φυσικών πληθυσμών του. Για την απομόνωση των μικροδορυφορικών δεικτών ακολουθήθηκαν τρεις διαφορετικές στρατηγικές: η κατασκευή και διαλογή γονιδιωματικών βιβλιοθηκών, η κατασκευή εμπλουτισμένων σε μικροδορυφόρους βιβλιοθηκών και ο έλεγχος ζευγών εκκινητών που είχαν σχεδιαστεί για την ενίσχυση μικροδορυφόρων στα συγγενικά είδη B. tyroni και C. capitata για το κατά πόσο ενισχύουν τις αντίστοιχες περιοχές και στο γονιδίωμα του εντόμου B. oleae (cross-species amplification). Από τις βιβλιοθήκες απομονώθηκαν συνολικά 69 κλώνοι που περιείχαν μικροδορυφόρους. Ακολούθησε ο σχεδιασμός ζευγών εκκινητών στις μοναδικές περιοχές που περιβάλλουν τους μικροδορυφόρους. Συνολικά σχεδιάστηκαν 42 ζεύγη εκκινητών. Οι εκκινητες αυτοί ελέγχθηκαν για το αν ενισχύουν το αναμενόμενο προϊόν. Ο έλεγχος έγινε με PCR και ηλεκτροφόρηση των προϊόντων σε πήκτωμα αγαρόζης. Παράλληλα ελέγχθηκαν είκοσι ζεύγη εκκινητών που είχαν σχεδιαστεί για μικροδορυφόρους του εντόμου B. tryoni και 42 ζεύγη εκκινητών που είχαν σχεδιαστεί για μικροδορυφόρους του εντόμου C. capitata. Οι τρεις διαδικασίες απομόνωσης έδωσαν συνολικά 67 λειτουργικά ζεύγη εκκινητών. Στη συνέχεια ελέγχθηκε μέσω PCR ο πολυμορφισμός των εκκινητών αυτών και το αν ενισχύουν διακριτά αλληλόμορφα, με μήτρα DNA γενετικό υλικό εννέα ατόμων. Τα προϊόντα της PCR αναλύθηκαν σε πήκτωμα ακρυλαμιδίου. Από τα 49 ζεύγη εκκινητών που ελέχθησαν, τα 28 έδωσαν πολύ καθαρό σήμα, ενώ τα 25 από αυτά βρέθηκαν πολυμορφικά. Μια πρώτη πληθυσμιακή ανάλυση έγινε με τη χρησιμοποίηση 24 από αυτούς τους δείκτες για την ανάλυση μικρού δείγματος ατόμων. Βασικός σκοπός της ανάλυσης αυτής ήταν να ελεγχθεί η ποιότητα των δεικτών και οδήγησε στον αποκλεισμό έξι δεικτών: ο ένας ήταν μονομορφικός, ένας δεύτερος έδειξε ασθενή ενίσχυση και μικρή επαναληψιμότητα και άλλοι τέσσερις εμφάνισαν απόκλιση από την ισορροπία κατά H-W, πιθανότητα λόγω της παρουσίας null αλληλομόρφων. Δώδεκα από τους υπόλοιπους δεκαοκτώ δείκτες χρησιμοποιήθηκαν για μια εκτεταμένη ανάλυση των πληθυσμών του δάκου στην Ευρωπαϊκή πλευρά της λεκάνης της Μεσογείου. Αναλύθηκαν δεκαεννέα δείγματα, μεγέθους εννέα ως πενήντα ατόμων, από έξι διαφορετικές χώρες (Ελλάδα, Κύπρος, Τουρκία, Ιταλία, Ισπανία και Πορτογαλία). Η ανάλυση αποκάλυψε σχετικά μικρές γενετικές αποστάσεις, που έδειχναν όμως μια στατιστικά σημαντική διαφοροποίηση σε τρεις υποπληθυσμούς. Ο πρώτος αποτελείτο από τα δείγματα της Κύπρου, ο δεύτερος από τα δείγματα Ελλάδας, Τουρκίας και Ισπανίας και ο τρίτος από τα δείγματα της Ιβηρικής χερσονήσου. Οι στατιστικές αναλύσεις που έγιναν έδειξαν τη σημαντική επίδραση της γεωγραφικής απόστασης στη δημιουργία αυτών των ομαδοποιήσεων. Οι τρεις αυτές ομάδες χαρακτηρίζονται από διαφορά και στο επίπεδο του πολυμορφισμού, εμφανίζοντας μια καθαρή μείωσή του από την Ανατολή προς τη Δύση. Η μείωση αυτή είναι στατιστικά σημαντική και με βάση την υπόθεση ότι η πορεία εποικισμού ενός είδους συνοδεύεται από μείωση του πολυμορφισμού, δίνει σημαντικές ενδείξεις για μία προς Δυσμάς πορεία εποίκισης του είδους στον Ευρωπαϊκό χώρο, με πρώτο κέντρο εξάπλωσης την Ανατολική λεκάνη της Μεσογείου. Τα πειράματα δια-ειδικής ενίσχυσης έδειξαν στενές φυλογενετικές σχέσεις των ειδών που εξετάστηκαν και κυρίως μεταξύ B. tryoni - B. oleae και B.oleae - C. capitata. Τα πειράματα αυτά υποστηρίζουν την χρησιμότητα των δεικτών που απομονώθηκαν σε ενδεχόμενες φυλογενετικές μελέτες στα είδη αυτά, καθώς και σε άλλα συγγενικά είδη. Η εύρεση ενός μεγάλου ποσοστού συντηρημένων μικροδορυφόρων σε είδη που έχουν διαχωριστεί εδώ και πολλά εκατομμύρια χρόνια ενισχύει την υπόθεση ότι οι μικροδορυφόροι δεν είναι γενετικό υλικό χωρίς ρόλο (junk DNA), αλλά επιτελούν συγκεκριμένες λειτουργίες στο γονιδίωμα. Η ανάλυση πολυμορφισμού που έγινε στις ατομικές διασταυρώσεις ατόμων από εργαστηριακούς ήταν ιδιαίτερα ενθαρρυντική. Ο υψηλός πολυμορφισμός που βρέθηκε δείχνει την δυνατότητα χρησιμοποίησης τους και στη γενετική χαρτογράφηση του είδους. / The olive fruit fly, Bactrocera oleae, is the main pest of the olive fruit. Because of its great economic importance, especially for the Mediterranean countries, there is a need for a more effective control method. The application of an integrated, environmental friendly, management of this pest requires a better knowledge of its biology and of the genetic structure of its natural populations. The aim of the present study was the development of DNA microsatellite markers for the analysis of the natural populations of the olive fruit fly. These markers are abundant in the genome of any species studied so far and highly polymorphic. Three different strategies were used for the isolation of microsatellite markers. The first was the construction and screening of genomic libraries of the insect, the second was the construction of genomic libraries, enriched for microsatellites and the third was the use of primer pairs that were designed for the amplification of microsatellite markers in the closely related species Bactrocera oleae and Ceratitis capitata(cross-species amplification). A total of 69 microsatellite containing clones were isolated from libraries. The next step was the design of primer pairs in the microsatellite flanking sequences. A total of 42 primer pairs was designed and tested for their abillty to amplify the expected product. Test was performed through PCR and analysis of the PCR products through electrophoresis on agarose gel. Twenty primer pairs designed for the amplification of Bactrocera tryoni’ s microsatellites and 42 primer pairs designed for the amplification of Ceratitis capitata microsatellites were also tested. All three strategies gave 67 primer pairs that amplified the expected product. The degree of polymorphism of these primer pairs and their ability to amplify easily resolvable alleles was tested through PCR with DNA template of nine individuals. PCR products were analysed through polyacrylamide gel electrophoresis. Twenty eight out of the 49 primer pairs tested produced clear bands and twenty five of them were polymorphic. A small scale population analysis was then performed, using tventy four of the markers available. The main purpose of this analysis was to demonstate the quality of the markers and lead to the exclusion of six markers: one of them was monomorphic, another didn’t show reproducible results and four more showed deviations from H-W equilibrium, probably because of the presence of null alleles. Twelve of the remaining loci were used in a large scale analysis of B. oleae’s populations in the European part of the Mediterranean basin. Nineteen samples, varying from nine to fifty individuals, were analysed. These samples were collected from six different countries (Greece, Cyprus, Turkey, Italy, Spain and Portugal). The analysis revealed relatively low genetic distances, which, however, demonsrated a statistically important differentiation of the samples in three subpopulations. The first consisted of the samples from Cyprus, the second of the samples from Greece, Turkey and Italy and the third of the samples from the Iberian Peninsula. The statistical analyses performed showed the statistically important contribution of geographic distance to the generation of genetic distance. These three groups of samples also demonstrate a clear loss of polymorphism towards West. This loss is statistically important and, if we take into account the hypothesis that the colonization process of a species is followed by a loss in polymorphism, it suggests a colonization process of the olive fruit fly towards West in the European part of the Mediterranean basin, with a first expansion area in the Eastern part of the Mediterranean basin. Cross-species amplification experiments indicate close phylogenetic relationships among the species studied, mainly between B. tryoni-B. oleae and B. oleae-C. capitata. These results support the usefulness of the markers isolated in phylogenetic studies in these species, as well as in other, closely related species. The identification of a high percentage if conserved microsatellites in species that have been well separated for millions of years is in agreement with the hypothesis that microsatellites are not useless genomic regions (junj DNA) but they perform specific functions in the genome. Polymorphism analysis in the crosses of individuals from laboratory strains was very encouraging. The high degree of polymorpism showes that they can be used in genetic mapping of the species
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Evolução geomorfológica e tectônica da porção norte da Bacia do Amazonas: região do Rio Apuaú (AM) / Geomorphological and tectonic evolution of the northern portion of the Amazon Basin: Apuaú River region (AM)Nascimento, Mayara Aline Santos Ribeiro do [UNESP] 08 November 2016 (has links)
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Previous issue date: 2016-11-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A paisagem na Amazônia tem mostrado um quadro geomorfológico evolutivo associado a condicionamentos tectônicos no controle da rede de drenagem, com importantes mudanças nos cursos dos rios associadas a sistemas de falhas no âmbito da Neotectônica. Esta pesquisa compreende o estudo da bacia hidrográfica do rio Apuaú, afluente da margem esquerda do rio Negro na sua porção média, a norte de Manaus, no Estado do Amazonas. Foi subsidiada por estudos estruturais e geomorfológicos apoiados em dados de campo, de sensores remotos e de datação dos depósitos aluvionares. Foram reconhecidos blocos desnivelados do relevo, com rupturas de declive (knickpoints) associadas e controladas por falhas. A rede de drenagem apresenta padrões anômalos dos cursos d’água, capturas, meandros e canais encurvados, alinhamento de canais retilíneos, marcando zonas de juntasou zonas de falhas. Os blocos controlam também a distribuição de terraços, paleoterraços e canais abandonados, e suas datações por LOE apontam para depósitos mais antigos na faixa de 53.000 a 62.200 anos, intermediários na faixa de 20.330 a 23.100 anos, e depósitos atuais. O quadro geológico-estrutural aponta para compartimentos morfotectônicos, controlados por falhas normais e falhas transcorrentes destrais associadas. As falhas normais condicionam blocos rotacionados, a rede de drenagem e a distribuição dos depósitos aluvionares, enquanto as falhas transcorrentes parecem balizar e controlar os blocos na porção norte e leste da bacia hidrográfica. Reconhecidas em campo, as falhas normais formam dois grandes conjuntos, orientados NE-SW a EW e NW-SE, enquanto as falhas transcorrentes destrais predominam com orientação próxima a EW e transcorrentes sinistrais NE-SW. O tratamento das populações de falhas para obtenção de eixos de paleotensões indica um evento distensivo NNW-SSE a NW-SE, interpretado como mais antigo, um evento distensivo NE-SW a EW, ao qual pode ser atribuído o ajuste dos blocos rotacionados, controlados por falhas NW-SE, e um arranjo compressivo NNW-SSE a NW-SE, responsável pelas falhas transcorrentes, ambos mais jovens. A associação entre as falhas transcorrentes destrais EW balizando os blocos abatidos e rotacionados controlados por falhas normais NW-SE promove o rearranjo da rede de drenagem e o ajuste da distribuição das coberturas superficiais, indicando atuação do regime neotectônico, decorrente da interação da Placa Sulamericana com a Placa do Caribe. / The landscape in the Amazon has shown a geomorphological evolution associated to tectonic constraints in controlling the drainage network, with important changes in the stream courses associated with fault systems within the scope of the neotectonic regime. This research comprises the study of the catchment of the Apuaú river, a tributary of the left bank of the Negro river in its middle portion, North of Manaus, in the state of Amazonas. Structural and geomorphological studies supported by field data, remote sensing and dating of alluvial deposits were carried out. Uneven relief blocks were recognized with associated slope ruptures (knickpoints) and controlled by faults. The drainage network has anomalous patterns of water courses, captures, meanders and curved channels, rectilinear alignment of channels, indicating fracture or fault zones. The blocks also control the distribution of terraces, paleoterraces and abandoned channels, and their LOE datings point to older deposits in the range 53,000 to 62,200 years, intermediate ones in the interval of 20,330 to 23,100 years and current deposits. The geological and structural framework points to morphotectonic compartments controlled by normal faults and associated dextral strike-slip faults. Normal fault constrain rotated blocks, drainage network and the distribution of alluvial deposits, while the strike-slip faults seem to delimit and control the blocks in the northern and eastern parts of the hydrographic basin. Recognized in the field, normal faults adjust into two large sets, oriented NE-SW to EW and NW-SE, while strike-slip faults predominate striking close to EW dextral and NE-SW sinistral ones. Fault population analysis to obtain paleostress axis indicates a NNW-SSE to NW-SE extensional event, interpreted as the oldest, followed by one NE-SW to EW distensive event, which can be attributed to the adjustment of rotated blocks, controlled by NW-SE faults, and a compressive arrangement NNW-SSE to NW-SE, responsible for the slip faults.The association between the EW dextral transcurrent faults controlling uneven and rotated blocks affected by NW-SE normal faults promotes the rearrangement of the drainage system and adjusting the distribution of surface covers, indicating actions of the neotectonic regime, due to the interaction of the South American Plate with the Caribbean Plate.
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Genetic analysis of Helosciadium repens (Jacq.) W.D.J.Koch populations in Germany - Fundamental research for conservation managementHerden, Tobias 03 February 2020 (has links)
Crop wild relatives (CWR) are an indispensable and at the same time threatened genetic resources for plant breeding. The study uses wild species related to celery to demonstrate how genetic resources of CWRs can be actively maintained in their natural surroundings (in-situ). Genetic reserves should be designated for long term conservation of selected occurrences.
The study presents the selection procedure in detail, aiming at the identification of occurrences and sites suitable for the designation of genetic reserves, the spatial model of a genetic reserve and first practical results of the project. The overall aim of the project is the establishment of a nationwide network of genetic reserves for Apium graveolens, Helosciadium repens, H. nodiflorum and H. inundatum, the four wild celery species native to Germany.
Helosciadum repens (Jacq.) W.D.J.Koch is threatened by genetic erosion due to a decline in population numbers and sizes. The loss of any population is an irretrievable loss of diversity and opportunity to enhance crops in the future. Genetic reserves are one way to conserve these populations and their genetic potential.
Twenty-seven populations were selected for the analysis in a decision process based on site information. Microsatellites (SSR) were used to elucidate the genetic diversity of German populations. A cluster analysis was performed to see if the individuals form clusters of similarity. For that, a discriminate analysis of principal components (DAPC) was conducted, as the inbreeding index indicated a high number of inbreeding events in the populations and thus discordance with HWE (Hardy-Weinberg equilibrium). The analysis identified six genetic groups, which coincide well with the geographic origin of the analysed plants. The allelic richness (mean counts of alleles per individual per population) was higher in the southern populations compared to the northern ones. This North-South discrepancy was also visible as a high heterogeneity in the cluster assignments in the DAPC analysis. These differences in genetic diversity might be a result of the biogeographic history of Europe, especially the last glacial maximum.
For the establishment of genetic reserves, two populations were considered as most important: The population that differs the most from the average genetic composition and the population that represents the average genetic composition of a population the best. The two extremes of differentiation were interpreted as such that the former has a specific adaptation to its local environment, and the latter represents all populations the best.
DifferInt was used to analyse the SSR data and validate the differentiation of all populations compared to a pool of populations. However, SSRs are not capable of detecting adaptive traits. Populations were additionally chosen from different eco-geographic units (EGU), to increase the chance of capturing different traits. EGUs (Naturräume) are areas of specific abiotic and biotic features. These features may influence selection pressures and induce local adaptations. Based on site parameters and genetic data, 14 most appropriate wild populations (MAWP) were identified for genetic reserves establishment.
For H. repens, two eco-forms are known and described in the literature. Besides their different habitats (terrestrial/semi-terrestrial and aquatic) they can be differentiated by morphological traits. Leave and stolon sizes and flowering behaviour differ significantly. Furthermore, the roots of the aquatic forms do not anchor in soil but on other aquatic plants, wood or roots of trees, while the terrestrial form exhibits a shallow root system network similar to other perennial species.
To this end, no genetic analysis was conducted to clarify the phylogenetic status of the putative forms and authors avoided the usage of any specific noun rather than form. The SSR data from the previous study was evaluated, particularly with regards to the two forms. Additionally, an ISSR analysis was conducted, and the data was used to perform a PCA. There was no genetic clustering regarding the two forms neither in the SSR nor in the ISSR data. Nonetheless, the North-South discrepancy in the genetic diversity that was visible in the DAPC plot was confirmed in the PCA of the ISSR data.
However, markers may fail to detect quantitative variation for adaptively important traits. As the most obvious difference in the two habitats was the water availability, the adaptation of both forms to drought stress was studied by measuring the relative water content of leaves, system water content and water loss during drought stress conditions. The stomatal index was measured for different water treatment levels. The results indicate that phenotypic plasticity rather than genotypic adaptation is responsible for different H. repens phenotypes.
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Representation of individual finger movements in macaque areas AIP, F5 and M1Sheng, Wei-An 21 June 2018 (has links)
No description available.
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Ageing assessment of transformer insulation through oil test database analysisTee, Sheng Ji January 2016 (has links)
Transformer ageing is inevitable and it is a challenge for utilities to manage a large fleet of ageing transformers. This means the need for monitoring transformer condition. One of the most widely used methods is oil sampling and testing. Databases of oil test records hence manifest as a great source of information for facilitating transformer ageing assessment and asset management. In this work, databases from three UK utilities including about 4,600 transformers and 65,000 oil test entries were processed, cleaned and analysed. The procedures used could help asset managers in how to approach databases, such as the need for addressing oil contamination, measurement procedure change and oil treatment discontinuities. An early degradation phenomenon was detected in multiple databases/utilities, which was investigated and found to be caused by the adoption of hydrotreatment oil refining technique in the late 1980s. Asset managers may need to monitor more frequently the affected units and restructure long term plans. The work subsequently focused on population analyses which indicated higher voltage transformers (275 kV and 400 kV) are tested more frequently and for more parameters compared with lower voltage units (33 kV and 132 kV). Acidity is the parameter that shows the highest correlation with transformer in-service age. In addition, the influence of the length of oil test records on population ageing trends was studied. It is found that it is possible to have a representative population ageing trend even with a short period (e.g. two years) of oil test results if the transformer age profile is representative of the whole transformer population. Leading from population analyses, seasonal influence on moisture was investigated which implies the importance of incorporating oil sampling temperature for better interpretation of moisture as well as indirectly breakdown voltage records. A condition mismatch between dielectric dissipation factor and resistivity was also discovered which could mean the need for revising the current IEC 60422 oil maintenance guide. Finally, insulation condition ranking was performed through principal component analysis (PCA) and analytic hierarchy process (AHP). These two techniques were demonstrated to be not just capable alternatives to traditional empirical formula but also allow fast, objective interpretation in PCA case, as well as flexible and comprehensive (objective and subjective incorporations) analysis in AHP case.
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