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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.
501

Localization and characterization of genes involved in parathyroid tumor development /

Forsberg, Lars, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.
502

Deletion mapping of human 3P in major epithelial malignancies and fine localization of candidate tumor suppressor genes /

Liu, Jian, January 2003 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.
503

Bouquet formation, rapid prophase movements and homologous pairing during meiotic prophase in Saccharomyces cerevisiae

Lee, Chih-ying. January 2009 (has links) (PDF)
Thesis (Ph. D.)--University of Oklahoma. / Bibliography: leaves 139-152.
504

Mitotic regulation of Aurora B kinase by TD-60 /

Nitcher, Sara Eileen Rosasco. January 2008 (has links)
Thesis (Ph. D.)--University of Virginia, 2008. / Includes bibliographical references. Also available in electronic form as viewed 2/16/2009.
505

Genetic information values and rights the morality of presymptomatic genetic testing /

Juth, Niklas. January 1900 (has links)
Thesis (doctoral)--Göteborg University, 2005. / Includes bibliographical references (p. 438-449) and index.
506

Genetic information values and rights the morality of presymptomatic genetic testing /

Juth, Niklas. January 1900 (has links)
Thesis (doctoral)--Göteborg University, 2005. / Includes bibliographical references (p. 438-449) and index.
507

Epidemiology of hereditary prostate cancer : genetic analysis of susceptibility loci incorporating clinical characteristics /

Goode, Ellen Lee. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 137-144).
508

Σχεδιασμός - υλοποίηση ολοκληρωμένου γραφικού περιβάλλοντος gene expression programming και ανάπτυξη καινοτόμων τελεστών

Αντωνίου, Μαρία 25 January 2012 (has links)
Τo Gene Expression Programming - GEP (Προγραμματισμός Γονιδιακής Έκφρασης - ΠΓΕ) είναι μια μέθοδος αυτόματης παραγωγής προγραμμάτων η οποία ανήκει στη γενική κατηγορία των Εξελικτικών Αλγορίθμων, εκείνων των τεχνικών δηλαδή που εμπνέονται από τις φυσικές διεργασίες της βιολογικής εξέλιξης. Συγκεκριμένα ο ΠΓΕ χρησιμοποιεί πληθυσμούς από άτομα, επιλέγει τα άτομα σύμφωνα με την καταλληλότητά τους (fitness) και εισάγει νέα σημεία (άτομα, πιθανές λύσεις) στον πληθυσμό χρησιμοποιώντας έναν ή περισσότερους γενετικούς τελεστές. Στόχος αυτής της Μεταπτυχιακής Διπλωματικής Εργασίας ήταν ο σχεδιασμός και η υλοποίηση ενός Ολοκληρωμένου Γραφικού Περιβάλλοντος για τον Προγραμματισμό Γονιδιακής Έκφρασης καθώς και η υλοποίηση ορισμένων καινοτομιών. Στα πλαίσια της διπλωματικής εργασίας, σχεδιάσθηκε και αναπτύχθηκε ένας καινοτόμος τελεστής για την μέθοδο του ΠΓΕ. Ο συγκεκριμένος τελεστής πραγματοποιεί μια τοπική αναζήτηση στις μεταβλητές που χρησιμοποιούνται στη μοντελοποίηση του εκάστοτε προβλήματος και επιλέγει εκείνες τις μεταβλητές για τις οποίες η απόδοση του αλγορίθμου βελτιστοποιείται. Η απόδοση του καινούργιου τελεστή ελέγχθηκε και πειραματικά. Μια επιπλέον καινοτομία που εφαρμόστηκε είναι η αυξομείωση του αριθμού των μεταλλάξεων. Συγκεκριμένα, επιλέγουμε να μειώνουμε τον αριθμό των μεταλλάξεων καθώς ο πληθυσμός εξελίσσεται, ενώ τον αυξάνουμε όταν έχουμε μικρή διαφορά ανάμεσα στη βέλτιστη και τη μέση απόδοση του πληθυσμού. Ο μεταβλητός αριθμός μεταλλάξεων σε συνδυασμό με την ικανότητα της μεθοδολογίας του ΠΓΕ να αποφεύγει τα τοπικά ακρότατα βελτιώνει σημαντικά την προσαρμοστικότητα του αλγορίθμου. Επιπλέον, για την αντιμετώπιση της αυξημένης υπολογιστικής πολυπλοκότητας που παρουσιάζει η μέθοδος, εισήχθη η έννοια του παραλληλισμού. Τέλος, η τροποποιημένη μέθοδος του ΠΓΕ εφαρμόστηκε σε πληθώρα προβλημάτων όπως η μοντελοποίηση συμπεριφοράς μιας χρονοσειράς μαγνητοεγκεφαλογραφήματος, η μοντελοποίηση της συμπεριφοράς κόπωσης υλικών, η πρόβλεψη ισοτιμίας δολαρίου – ευρώ, η πρόβλεψη πρωτεϊνικών αλληλεπιδράσεων και η πρόβλεψη του βαθμού υδατοκορεσμού ελαιοκαλλιεργειών. Τα αποτελέσματα που προέκυψαν είναι ιδιαίτερα ενθαρρυντικά. / Gene Expression Programming (GEP) is one method of automatic generation of programs that belongs to a wider class of Evolutionary Algorithms. Evolutionary Algorithms are inspired by biological mechanisms of evolution. Specifically, GEP uses populations of individuals, select the individuals according to their fitness, and introduce genetic variation using one or more genetic operators. The purpose of this Master's Thesis was to design and implement an Integrated Graphical Environment for Gene Expression Programming and the implementation of certain innovations. Ιn the context of this thesis an innovative operator was designed and developed for the GEP method. This particular operator is conducting a local search on the variables used in modeling of a problem and chooses those variables for which the performance of the algorithm is optimized. The performance of the new operator was experimentally tested. Another innovation implemented was the fluctuation in the number of mutations. Specifically, we choose to reduce the number of mutations as the population evolves, while we increase it when the performance of the best individual found is very close to the average performance of the population. The variable number of mutations in combination with the ability of the methodology of GEP to avoid local extrema significantly improves the adaptability of the algorithm. Moreover, in order to face the increased computational complexity of the method, we introduce parallelism. Finally, the modified method of GEP was applied to many problems such as modeling behavior of a MEG’s time series, modeling of fatigue behavior of materials, forecasting Euro - United States Dollar exchange rate, predicting protein interactions and predicting the degree of saturation of olive crops. The results are very encouraging.
509

Caracterização morfológica e citogenética de sementes e plântulas de algumas espécies de plantas tóxicas /

Andrade, Débora Aparecida Verde de. January 2007 (has links)
Orientador: Fabíola Vitti Môro / Banca: Emerson Ricardo Pansarin / Banca: Ricardo Machado da Silva / Resumo: Este trabalho teve como objetivo caracterizar morfologica e citogeneticamente as especies de plantas toxicas: Crotalaria lanceolata E. Mey., Ricinus communis L., Cassia occidentalis L. , Canavalia ensiformis D.C. e Amaranthus spinosus L.. Para a morfologia utilizou-se sementes e plantulas que foram esquematizadas com auxilio de estereomicroscopio equipado com camara clara.Para a citogenetica utilizou-se pontas de raizes, hidroxiquinoleina e coloracao Giemsa. Crotalaria lanceolata E. Mey. apresenta sementes com variados tons de castanhos. A germinacao e epigea e fanerocotiledonar. O embriao e cotiledonar e o endosperma mucilaginoso. Apresenta numero cromossomico 2n = 16 cromossomos, com comprimento medio geral de 3,340 Êm } 0,689. Ricinus communis L. possui sementes com testa mesclada em tons castanhos, com caruncula visivel localizada na parte inferior da semente, germinacao epigea e fanerocotiledonar.O embriao e cotiledonar e o endosperma oleaginoso. O numero cromossomico 2n = 10 cromossomos, com comprimento cromossomico medio de 1,123 Êm } 0,327. Cassia occidentalis apresenta sementes com tons marrom-escuro, embriao cotiledonar e endosperma mucilaginoso. A germinacao e epigea e fanerocotiledonar. Possui 2n = 26 cromossomos com comprimento cromossomico medio e de 1,672 0,400. Canavalia ensiformis D.C apresenta sementes com uma coloracao branca e lignificada, embrião cotiledonar e endosperma mucilaginoso. A germinacao e do tipo epigea e fanerocotiledonar. Apresenta numero cromossomico 2n = 22 cromossomos com comprimento medio de 1,388 Êm 0,249...... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work had as objective to characterize morphologic and citogenetics some species of toxic plants: Crotalaria lanceolata E. Mey., Ricinus communis L., Cassia occidentalis L., Canavalia ensiformis D. C. and Amaranthus spinosus L.. For the morphological studies were used seeds and seedlings that were schematized with of stereomicroscoppe equipped with camera lucida. The cytogenetic already used points of rootses, Hidroxiquinoleina and Giemsa coloration. Crotalaria lanceolata E. Mey. present seeds with varied tones of chestnut . Its germination is phanerocotyledonar and epigeous. The seeds are kidney shaped and the embryo is cotyledonary with a mucilaginous endospermic. They present chromosome number 2n = 16 chromosomes, with general medium length of 3,340mm l 0,689. Ricinus communis L. presents seeds with forehead several mixed many tones chestnut, wich visible caruncula located in the inferior part of the seed, germination is phanerocotyledonar and epigeous. The seeds are kidney shaped and the embryo is cotyledonary and an oleaginous endospermic. Its chromosome number is 2n = 10 chromosomes, with length medium chromossomic of 1,123mm l 0,327. Cassia occidentalis presents seed with tones brown-darkness whose interior presents an embryo is cotyledonary and a mucilaginous endospermic. Its germination is phanerocotyledonar and epigeous. The evaluation cytogenetic shows us 2n = 26 chromosomes with length medium chromossomic are of 1,672mm l 0,400. Canavalia ensiformis D.C presents seeds with a white coloration and lignification. In its interior it is located an embryo cotyledonary... (Complete abstract, click electronic access below) / Mestre
510

A behavioural and genomic approach to studying the evolution of reproductive isolation : a contact zone between closely related field crickets in the genus Teleogryllus

Moran, Peter January 2017 (has links)
What processes contribute to the evolution of reproductive isolation and the coexistence of interfertile species in the same habitat? This thesis investigates the relative roles of species interactions and intraspecific processes in contributing to reproductive isolation. I combine behavioural and genomic approaches to test hypotheses about what mechanisms maintain the general species boundary between two closely related field cricket species: Teleogryllus oceanicus and T. commodus. These species are a classic study system for sexual communication and readily hybridize in the laboratory, however little is known about species interactions in sympatric populations. I examine patterns of geographic variation in two key sexual traits: calling song and cuticular hydrocarbons (CHCs), and the geographic distribution of genetic variation across a broad sample of allopatric and sympatric populations. I test whether X chromosomes play a pronounced role in population divergence and reproductive isolation. Using close range mating trials and hybridization experiments I identify numerous pre-mating and post-mating barriers between the species. The results indicate that the species are currently reproductively isolated and the pattern of population differentiation does not strongly support contemporary species interactions contributing to phenotypic diversity. Numerous barriers exist between the species, in particular hybrid females are sterile in both cross directions, while hybrid males are relatively fertile. This provides a rare exception to Haldane's rule which is central to many genetic theories of speciation. Established theory predicts that X chromosomes should play a pronounced role in the evolution of both pre- and postzygotic barriers. Contrary to this, I found no evidence that X chromosomes contribute to hybrid female sterility. Moreover, X-linked loci exhibited an unexpected pattern of reduced population differentiation within species, but increased species divergence compared to autosomal loci, which may indicate selective sweeps or sex-biased processes. Taken together, the results suggest that the causes and consequences of X chromosome evolution, in particular among XO taxa, may contradict some of the established theories.

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