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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.
231

Data Perspectives of Workflow Schema Evolution : Cases of Task Deletion and Insertion

Arunagiri, Aravindhan January 2013 (has links) (PDF)
Dynamic changes in the business environment requires their business process to be up-to-date. The Workflow Management Systems supporting these business processes need to adapt to these changes rapidly. The Work Flow Management Systems however lacks the ability to dynamically propagate the process changes to their process model schemas (Workflow templates). The literature on workflow schema evolution emphasizes the impact of changes in control flow with very ittle attention to other aspects of a workflow schema. This thesis studies the data aspect (data flow and data model) of workflow schema during its evolution. Workflow schema changes can lead to inconsistencies between the underlying database model and the workflow. A rather straight forward approach to the problem would be to abandon the existing database model and start afresh. However this introduces data persistence issues. Also there could be significant system downtimes involved in the process of migrating data from the old database model to the current one. In this research we develop an approach to address this problem. The business changes demand various types of control flow changes to its business process model (workflow schema). The control flow changes include task insertion, deletion, swapping, movement, replacement, extraction, in-lining, Parallelizing etc. Many of the control flow changes to the workflow can be made by using the combination of a simple task insertion and deletion, while some like embedding task in loop/ conditional branch and Parallelizing tasks also requires the addition/removal of control dependency between the tasks. Since many of the control flow change patterns involves task insertion and deletion at its core, in this thesis we study its impact on the underlying data model. We propose algorithms to dynamically handle the changes in the underlying relational database schema. First we identify the basic change patterns that can be implemented using atomic task insertion and deletions. Then we characterize these basic pattern in terms of their data flow anomalies (Missing, Redundant, Conflicting data) that they can generate. The Data schema compliance criteria are developed to identify the data changes: (i) that makes the underlying database schema inconsistent with the modified workflow and (ii) generating the aforementioned data anomalies. The Data schema compliance criteria characterizes the change patterns in terms of its ability to work with the current relational data model. The Data schema compliance criteria show various properties required of the modified workflow to be consistent with the underlying database model. The data of any workflow instance conforming to Data schema compliance criteria can be directly accommodated in the database model. The data anomalies (of task insertion and deletion) identified using DSC are handled dynamically using respective Data adaptation algorithms. The algorithm uses the functional dependency constraints in the relational database model to adapt/handle these data anomalies. Such handled data (changes) that conform to DSC can be directly accommodated in the underlying database schema. Hence with this approach the workflow can be modified (using task insertion and deletion) and their data changes can be implemented on-the-fly using the Data adaptation algorithms. In this research the same old data model is evolved without abandoning it even after the modification of the workflow schema. This maintains the old data persistence in the existing database schema. Detailed implementation procedures to deploy the Data adaptation algorithms are presented with illustrative examples.
232

La délétion génétique du récepteur corticotropin-releasing factor de type 2 réduit les déficits mnésiques et sociaux induits par la cocaïne / Corticotropin-releasing factor 2 receptor-deficiency reduces memory and social deficits induced by cocaine

Morisot, Nadège 16 December 2013 (has links)
Les travaux de cette thèse visent à étudier le role du système corticotropin-releasing factor (CRF) dans les dysfonctions cognitives, les altérations du comportement social et la vulnérabilité au stress associées à l’addiction aux drogues. Les effets de la délétion génétique du récepteur CRF1 ou CRF2 sont examinés dans les tests de reconnaissance d’objet et de préférence sociale après une exposition chronique et pendant le sevrage à la cocaine. Le rôle du récepteur CRF2 dans la vulnérabilité au stress qui pourrait précipiter l’apparition de déficits cognitifs et sociaux pendant le sevrage prolongé à la cocaine est également étudié. / Stimulant-related disorders are characterized by emotional-like, cognitive and social dysfunction that may contribute to the maintenance of the disease. In addition, stimulant use and withdrawal may alter brain stress systems. The corticotropin-releasing factor (CRF) system is a major stress coordinator hypothesized to contribute to substance-related disorders. CRF signalling is mediated by two receptor types, named CRF1 and CRF2. The specific role of each of the CRF receptors in negative affective-like, cognitive and social dysfunction associated with stimulant administration and withdrawal remains largely unknown. The present study demonstrates that the CRF1 receptor-deficiency increases the anxiety-like behaviour induced by intermittent administration of escalating doses of cocaine (5-20 mg/kg, i.p.), as assessed by the elevated plus maze. In addition, the same cocaine regimen induces novel object recognition (NOR) and sociability deficits, which are unaffected by CRF2 receptor-deficiency. However, CRF2 receptor-deficiency effectively shortens the duration of the NOR and sociability deficit induced by cocaine withdrawal. Furthermore, following the apparent recovery of NOR and sociability performances during relative long-term (42 days) cocaine withdrawal, CRF2 receptor-deficiency eliminates the stress-induced re-emergence of NOR and sociability deficit. Stressed cocaine-withdrawn mice show a genotype-independent higher c-fos mRNA expression in the perirhinal cortex, a brain region mediating NOR performance, than stressed drug-naïve mice. However, neither genotype nor drug withdrawal affects the expression of tyrosine hydroxylase in the ventral tegmentale area and the locus coeruleus, CRF in the amygdala and the paraventricular nucleus of the hypothalamus and dynorphin in the nucleus accumbens shell. The latter results suggest that stress vulnerability during long-term cocaine withdrawal is not due to alterations in stress-coping mechanisms. The present study provides initial evidence of a critical role for the CRF system in cognitive and sociability deficits and vulnerability induced by stimulant administration and withdrawal, suggesting new therapeutic strategies for substance-related disorders.
233

Polimorfismos de inserção/deleção no cromossomo X : análise de 32 marcadores na população da região sudeste do Brasil /

Silva, Flávia Alves de Jesus. January 2020 (has links)
Orientador: Regina Maria Barreto Cicarelli / Resumo: Na rotina forense, há casos em que a amostra biológica se encontra degradada ou com baixa concentração de DNA, o uso exclusivo dos marcadores STRs pode gerar um resultado estatístico inconclusivo, tornando fundamental a análise de marcadores adicionais para a resolução do caso. Utilizado como método complementar, os polimorfismos de inserção e deleção (InDels) têm mostrado grande potencial para superar as limitações dos marcadores tradicionais. Adicionalmente, estudos de genética forense tem sido cada vez mais explorados no âmbito do cromossomo X, especialmente nos casos em que a análise dos autossômicos não é suficiente. Nessa perspectiva, este trabalho avaliou a utilidade de um conjunto de 32 polimorfismos de inserção/deleção do cromossomo X em amostras da população da região sudeste do Brasil. Afim de avaliar a diversidade genética destas populações, foram analisados os perfis genotípicos de 627 indivíduos sem relação genética pelo cromossomo X, residentes nos estados de Minas Gerais (90 mulheres e 116 homens), Espírito Santo (201 homens) e Rio de Janeiro (220 homens). Os resultados indicam que o painel dos 32 X-InDels é bastante eficiente para a sua finalidade, sendo que praticamente todos os marcadores se mostraram altamente informativos para as populações estudadas. O teste de equilíbrio de Hardy-Weinberg foi realizado nas amostras femininas de Minas Gerais e não foram verificados desvios significativos. Em todas populações analisadas o painel demonstrou alta eficiência... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the forensic routine, there are cases in which the biological sample is degraded or with a low concentration of DNA, the exclusive use of STR markers can generate an inconclusive statistical result, making the analysis of additional markers essential for the resolution of the case. Used as a complementary method, the insertion and deletion polymorphisms (InDels) have shown great potential to overcome the limitations of traditional markers. Additionally, the X chromosome has been increasing significant importance in forensic genetics studies, especially in cases where the analysis of autosomal is not enough. In this perspective, this work evaluated the usefulness of a set of 32 polymorphisms of insertion/deletion of the X chromosome in samples from the population of the southeastern region of Brazil. In order to evaluate the genetic diversity of these populations, the genotypic profiles of 627 individuals without genetic relationship were analyzed by the X chromosome, living in the states of Minas Gerais (90 females and 116 males), Espírito Santo (201 males) and Rio de Janeiro (220 males). The results indicate that the 32 X-InDels panel is enough efficient for its purpose, with practically all the markers proving to be highly informative for the studied populations. The Hardy-Weinberg equilibrium test was performed on female samples from Minas Gerais and no significant deviations were found. In all analyzed populations, the panel demonstrated high forensic efficiency, confi... (Complete abstract click electronic access below) / Doutor
234

Analýza chybějících hodnot: porovnání vhodnosti tradičních metod napříč mechanismy / Analysis of Missing Data: Comparing Performance of Traditional Methods across Mechanisms

Petrúšek, Ivan January 2014 (has links)
The objective of this thesis is to evaluate different methods of dealing with missing values in data analysis. The thesis is divided into three major chapters. The first chapter summarizes the theoretical literature on missing data and focuses on missing data mechanisms in particular. The second chapter introduces traditional methods for addressing missing data in sociological research. The third chapter assesses the performance of these methods by analyzing simulated data sets for two variables (income, IQ). For practical analysis (chapter 3), we simulated missing data according to three different mechanisms (MCAR, MAR, NMAR) and varied the proportion of missing values under these mechanisms (10%, 20%, 30%). Then, we applied each of the following four methods of addressing missing values: complete-case analysis, arithmetic mean imputation, regression imputation, and stochastic regression imputation. In order to evaluate the performance of each of these methods we performed correlation and regression analyses for each experimental condition. The results of these simulations are largely in agreement with existing theoretical literature on the subject of missing data. In the case of NMAR, all solution methods provided biased parameter estimates. In the case of MCAR, only complete-case analysis and...
235

Algorithms to Resolve Large Scale and Complex StructuralVariants in the Human Genome

Hayes, Matthew 23 August 2013 (has links)
No description available.
236

Modulation génétique de la dynamique cérébrale dans les troubles neurodéveloppementaux : impact des CNVs pathogéniques sur l’EEG de repos

Audet-Duchesne, Elisabeth 08 1900 (has links)
Bien que la majeure partie du génome humain soit présente en deux copies (une copie héritée de chaque parent), certains segments peuvent être délétés (une copie) ou dupliqués (trois copies). La recherche a montré que plusieurs variations du nombre de copies (CNVs) augmentent le risque de troubles neurodéveloppementaux (e.g. autisme, TDAH, schizophrénie). Or, on connait peu les effets des CNVs sur le développement et le fonctionnement cérébral. L’électroencéphalographie (EEG) au repos s’avère être une méthode adaptée pour étudier les perturbations de l’activité neuronale chez les porteurs de CNVs. L’objectif de ce projet était de déterminer s’il existe des signatures EEG à l’état de repos qui sont caractéristiques des enfants porteurs de CNVs pathogéniques. L’activité cérébrale au repos de 109 porteurs de CNVs (66 délétions, 43 duplications) âgés de 3 à 17 ans a été enregistrée en EEG durant 4 minutes. Pour mieux prendre en compte les variations développementales, les indices EEG (puissance spectrale et connectivité fonctionnelle) ont été corrigés avec un modèle normatif estimé à partir de 256 contrôles du Heatlhy Brain Network. Les résultats ont montré une puissance bêta et gamma accrue dans les régions postérieures ainsi qu’une sous-connectivité globale à des échelles temporelles distinctes chez les porteurs de CNVs. Les porteurs d’une délétion et d’une duplication pouvaient être différenciés par leur connectivité dans les fréquences bas-alpha: la connectivité des porteurs d’une duplication était plus perturbée que celle des porteurs d’une délétion. Les perturbations distinctives en connectivité se sont avérées plus proéminentes à l’adolescence. Les résultats suggèrent que les porteurs de CNVs présentent des altérations électrophysiologiques par rapport aux témoins neurotypiques, indépendamment de la région génomique affectée. / Although most of the human genome is present in two copies (one copy inherited from each parent), some segments can be deleted (one copy) or duplicated (three copies). Research has shown that many copy number variations (CNVs) increase the risk of neurodevelopmental disorders (e.g. autism, ADHD, schizophrenia). However, little is known about the effects of CNVs on brain development and function. Resting-state electroencephalography (EEG) is a suitable method to study the disturbances of neuronal functioning in CNVs. We aimed to determine whether there are resting-state EEG signatures that are characteristic of children with pathogenic CNVs. Resting-state brain activity of 109 CNVs carriers (66 deletions, 43 duplications) aged 3 to 17 years was recorded in EEG for 4 minutes. To better account for developmental variations, EEG indices (power spectral density and functional connectivity) were corrected with a normative model estimated from 256 Heatlhy Brain Network controls. Results showed increased beta and gamma power in posterior regions as well as a global under-connectivity at distinct frequency bands in CNVs carriers. Deletion and duplication carriers can be differentiated by their connectivity in low alpha frequencies: the connectivity of the duplication carriers was more disrupted than that of the deletion carriers. The distinctive connectivity perturbations were found to be most prominent during adolescence. The results suggest that CNVs carriers show electrophysiological alterations compared to neurotypical controls, regardless of the gene dosage effect and of their affected genomic region. Moreover, a specific signature of the molecular alterations associated with deletions was found.
237

Construction and Analysis of a Genome-Wide Insertion Library in Schizosaccharomyces pombe Reveals Novel Aspects of DNA Repair

Li, Yanhui 09 February 2015 (has links)
No description available.
238

Frequent p16-independent inactivation of p14ARF in human melanoma

Freedberg, D.E., Rigas, S.H., Russak, J., Gai, W., Kaplow, M., Osman, I., Turner, F., Randerson-Moor, J.A., Houghton, A., Busam, K., Bishop, D.T., Bastian, B.C., Newton-Bishop, J.A., Polsky, D. January 2008 (has links)
No / BACKGROUND: The tumor suppressors p14(ARF) (ARF) and p16(INK4A) (p16) are encoded by overlapping reading frames at the CDKN2A/INK4A locus on chromosome 9p21. In human melanoma, the accumulated evidence has suggested that the predominant tumor suppressor at 9p21 is p16, not ARF. However, recent observations from melanoma-prone families and murine melanoma models suggest a p16-independent tumor suppressor role for ARF. We analyzed a group of melanoma metastases and cell lines to investigate directly whether somatic alterations to the ARF gene support its role as a p16-independent tumor suppressor in human melanoma, assuming that two alterations (genetic and/or epigenetic) would be required to inactivate a gene. METHODS: We examined the p16/ARF locus in 60 melanoma metastases from 58 patients and in 9 human melanoma cell lines using multiplex ligation-dependent probe amplification and multiplex polymerase chain reaction (PCR) to detect deletions, methylation-specific PCR to detect promoter methylation, direct sequencing to detect mutations affecting ARF and p16, and, in a subset of 20 tumors, immunohistochemistry to determine the effect of these alterations on p16 protein expression. All statistical tests were two-sided. RESULTS: We observed two or more alterations to the ARF gene in 26/60 (43%) metastases. The p16 gene sustained two or more alterations in 13/60 (22%) metastases (P = .03). Inactivation of ARF in the presence of wild-type p16 was seen in 18/60 (30%) metastases. CONCLUSION: Genetic and epigenetic analyses of the human 9p21 locus indicate that modifications of ARF occur independently of p16 inactivation in human melanoma and suggest that ARF is more frequently inactivated than p16.
239

Neural Wiskott-Aldrich syndrome protein modulates Wnt signaling and is required for hair follicle cycling in mice

Lyubimova, A., Garber, J.J., Upadhyay, G., Sharov, A.A., Anastasoaie, F., Yajnik, V., Cotsarelis, G., Dotto, G.P., Botchkarev, Vladimir A., Snapper, S.B. January 2010 (has links)
No / The Rho family GTPases Cdc42 and Rac1 are critical regulators of the actin cytoskeleton and are essential for skin and hair function. Wiskott-Aldrich syndrome family proteins act downstream of these GTPases, controlling actin assembly and cytoskeletal reorganization, but their role in epithelial cells has not been characterized in vivo. Here, we used a conditional knockout approach to assess the role of neural Wiskott-Aldrich syndrome protein (N-WASP), the ubiquitously expressed Wiskott-Aldrich syndrome-like (WASL) protein, in mouse skin. We found that N-WASP deficiency in mouse skin led to severe alopecia, epidermal hyperproliferation, and ulceration, without obvious effects on epidermal differentiation and wound healing. Further analysis revealed that the observed alopecia was likely the result of a progressive and ultimately nearly complete block in hair follicle (HF) cycling by 5 months of age. N-WASP deficiency also led to abnormal proliferation of skin progenitor cells, resulting in their depletion over time. Furthermore, N-WASP deficiency in vitro and in vivo correlated with decreased GSK-3beta phosphorylation, decreased nuclear localization of beta-catenin in follicular keratinocytes, and decreased Wnt-dependent transcription. Our results indicate a critical role for N-WASP in skin function and HF cycling and identify a link between N-WASP and Wnt signaling. We therefore propose that N-WASP acts as a positive regulator of beta-catenin-dependent transcription, modulating differentiation of HF progenitor cells.
240

The Human Y chromosome and its role in the developing male nervous system

Johansson, Martin M. January 2015 (has links)
Recent research demonstrated that besides a role in sex determination and male fertility, the Y chromosome is involved in additional functions including prostate cancer, sex-specific effects on the brain and behaviour, graft-versus-host disease, nociception, aggression and autoimmune diseases. The results presented in this thesis include an analysis of sex-biased genes encoded on the X and Y chromosomes of rodents. Expression data from six different somatic tissues was analyzed and we found that the X chromosome is enriched in female biased genes and depleted of male biased ones. The second study described copy number variation (CNV) patterns in a world-wide collection of human Y chromosome samples. Contrary to expectations, duplications and not deletions were the most frequent variations. We also discovered novel CNV patterns of which some were significantly overrepresented in specific haplogroups. A substantial part of the thesis focuses on analysis of spatial expression of two Y-encoded brain-specific genes, namely PCDH11Y and NLGN4Y. The perhaps most surprising discovery was the observation that X and Y transcripts of both gene pairs are mostly expressed in different cells in human spinal cord and medulla oblongata. Also, we detected spatial expression differences for the PCDH11X gene in spinal cord. The main focus of the spatial investigations was to uncover genetically coded sexual differences in expression during early development of human central nervous system (CNS). Also, investigations of the expression profiles for 13 X and Y homolog gene pairs in human CNS, adult brain, testes and still-born chimpanzee brain samples were included. Contrary to previous studies, we found only three X-encoded genes from the 13 X/Y homologous gene pairs studied that exhibit female-bias. We also describe six novel non-coding RNAs encoded in the human MSY, some of which are polyadenylated and with conserved expression in chimpanzee brain. The description of dimorphic cellular expression patterns of X- and Y-linked genes should boost the interest in the human specific gene PCDH11Y, and draw attention to other Y-encoded genes expressed in the brain during development. This may help to elucidate the role of the Y chromosome in sex differences during early CNS development in humans. / <p>chinese, finnish, norwegian, schizophrenia, bipolar, bipolar disorder, msy, male specific region Y, PAR1, PAR2, pseudoautosomal, male-biased, female-biased, male biased, female biased, ashkenazi population, structure, variants, YHRD, Elena Jazin, Björn Reinius, Per Ahlberg, brain, hjärna, CNS, central nervous system, IR2, inverted repeat 2, isodicentric, genetics, genetik, padlock, rolling circle, amplification, PCR, sY1191, sY1291, STS, DDX3Y, DAZ, AZFa, AZFb, AZFc, AZF, Repping, haplogroup J, rearrangements, DE-M145, I-M170, E-M96, Q-M242, R-M207, O-M175, G-M201, D-M174, C-M130, NO-M214, N-M231, poland</p>

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