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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.
1

Efecto a corto y largo plazo de diferentes períodos de isquemia transitoria en la supervivencia de las células ganglionares de la retina de rata adulta: estudio cuantitativo

Sellés Navarro, Inmaculada 24 November 1995 (has links)
La retina es un tejido nervioso que parece tener una mayor tolerancia ante situaciones de hipoxia que el resto del sistema nervioso central (SNC). Sin embargo, las consecuencias funcionales derivadas de la privación de flujo sanguíneo son graves y en la mayoría de los casos irreversibles. Se han realizado numerosas investigaciones con el fin de conocer las alteraciones morfológicas y funcionales de la retina ante situaciones de isquemia de diferente intensidad, sin embargo se carecen de estudios que caractericen específicamente el comportamiento de las células ganglionares de la retina (GCR) ante la isquemia utilizando métodos que nos permiten cuantificar la muerte de las (GCR). Queremos determinar su grado de tolerancia ante la isquemia, y estudiar el patrón de muerte de estas células tras someterlas a diferentes periodos de isquemia transitoria basándonos en técnicas neuroanatómicas. Hemos marcado las CGR con un trazador neuronal fluorescente, el fluoro-Gold, que aplicado en los principales núcleos de proyección de la vía óptica de la rata adulta nos ha permitido distinguir y diferenciar las CGR.
2

Localization with Time-of-Flight cameras / Positionering med Time-of-Flight kameror

Pettersson, Lucas January 2020 (has links)
Time-of-Flight (ToF) cameras are becoming an increasingly common sensor in smartphones. These sensors are able to produce depth measurements in a grid at a relatively high rate. Using these depth measurements, point-clouds representing the captured scene can be produced. Previous research has been conducted in using ToF or LIDAR images to localize the camera. In this paper, we investigate several methods to localize the camera using point-clouds and surface meshes. Small alterations were made to some of the algorithms but the concepts remain the same. The main algorithms consisted of ICP variants as well as a relatively recent method called Corrective Gradient Refinement (CGR). The results obtained from generated data indicate that some of the methods are applicable for real-time applications, and the position estimates are comparable to those found in previous results. / Time-of-flight (ToF)-kameror blir en allt vanligare sensor i mobiltelefoner. Dessa sensorer kan producera djupmätningar i ett rutnät med relativt hög frekvens. Med hjälp av dessa djupmätningar kan ett punktmoln som representerar den fångade scenen produceras. Tidigare forskning har gjorts med hjälp av ToF- eller LIDAR-bilder för att lokalisera kameran. Här undersöks flera metoder för att lokalisera kameran med hjälp av ett punktmoln och en triangulering av en modell. Algoritmerna bestod till största delen av ICP-varianter samt en relativt ny metod som heter Corrective Gradient Refinement (CGR). Resultaten som erhållits från genererade data indikerar att vissa av metoderna är lämplig för realtidsapplikationer och felet på positioneringen är jämförbart med dem som hittades i tidigare resultat.
3

Modèles prédictifs pour les paramètres cinétiques et thermodynamiques des réactions chimiques / Predictive models for kinetic and thermodynamic parameters of reactions

Gimadiev, Timur 11 July 2018 (has links)
Ce travail est consacré à la modélisation QSPR des propriétés cinétiques et thermodynamiques des réactions chimiques à l'aide de l'approche Graphe Condensé de Réaction (CGR). Le CGR permet de coder des structures de réactifs et de produits en un seul graphe moléculaire pour lequel des descripteurs moléculaires peuvent être générés.Une base de données contenant plus de 11000 réactions collectées manuellement a été développée puis utilisée dans la modélisation. Les modèles prédictifs ont été construits pour les constantes de vitesse de réactions Diels-Alder, SN2 et E2 ainsi que pour les constantes d'équilibre des transformations tautomères. Ils sont rendus publics via un portail WEB. Une partie de la thèse concerne une étude de mécanique quantique des réactions entre des sydnones et des alcynes contraints pour lesquels la taille du jeux de données n'était pas suffisante pour produire des modèles statistiquement significatifs. / This work is devoted to QSPR modeling of kinetic and thermodynamic properties of chemical reactions using the Condensed Graph of Reaction (CGR) approach. CGR allows encoding structures of reactants and products into one sole molecular graph for which molecular descriptors can be generated. A comprehensive database containing some 11000 manually collected reactions has been developed then used in the modeling. Predictive models were built for rate constants of Diels-Alder, SN2 and E2 reaction as well as for equilibrium constants of tautomeric transformations. They are available for the users via WEB portal. A part of the thesis concerned quantum mechanics studies of reactions between sydnones and strained alkynes for which the size of the dataset was not sufficient to produce statistically meaningful models.
4

Gestão e planejamento regional : o papel do Colegiado de Gestão Regional (CGR) no processo de regionalização da saúde em Mato Grosso

Pedrotti, Priscila Ono 03 July 2013 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2018-08-29T16:16:50Z No. of bitstreams: 1 DISS_2013_ Priscila Ono Pedrotti.pdf: 2474809 bytes, checksum: d0b05d9f704a34d75e10544ec41083bc (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-10-03T16:44:16Z (GMT) No. of bitstreams: 1 DISS_2013_ Priscila Ono Pedrotti.pdf: 2474809 bytes, checksum: d0b05d9f704a34d75e10544ec41083bc (MD5) / Made available in DSpace on 2018-10-03T16:44:16Z (GMT). No. of bitstreams: 1 DISS_2013_ Priscila Ono Pedrotti.pdf: 2474809 bytes, checksum: d0b05d9f704a34d75e10544ec41083bc (MD5) Previous issue date: 2013-07-03 / A Constituição Brasileira de 1988 criou o Sistema Único de Saúde (SUS), adotando a descentralização e a regionalização como estratégias para a consolidação deste Sistema. Desde então, muitas foram as iniciativas implementadas, com destaque para o Pacto pela Saúde, que institucionalizou os Colegiados de Gestão Regional (CGR), espaço de negociação e pactuação visando a gestão regional. O presente trabalho busca analisar este papel dos CGR, frente ao processo de regionalização em Mato Grosso. Método: Pesquisa qualitativa que constou de uma exploração dos 16 CGR constituídos no estado, mediante a utilização de questionário autoaplicado e de estudo de caso de dois CGR, escolhidos por critério de polaridade após análise de dados oriundos daquele questionário. O período de análise referiu-se aos anos de 2006 a 2012. O foco da investigação deu-se na conformação do CGR, no seu funcionamento, sua organização e relações, principalmente à luz da gestão e planejamento, buscando apreender como se dá essa prática no nível regional. Resultados: O incentivo precoce dado à regionalização da saúde em Mato Grosso fortaleceu as instâncias regionais (CIB Regionais e CGR) e a institucionalidade materializou-se, principalmente no que tange aos seus componentes regulatório e normativo. Deram-se avanços também na governança, já que no âmbito do CGR, interesses de sujeitos, governos e organizações são contemplados e pactuados. No entanto, a partir dos questionário autoaplicados, da base documental analisada e do estudo de caso, são evidenciadas as limitações da gestão estadual na coordenação e na indução do processo de regionalização da saúde, comprometendo sobremaneira a gestão do SUS neste estado. / The Brazilian Constitution of 1988 created the National Health System (SUS), adopting decentralization and regionalization as strategies to consolidate this system. Since then, many initiatives have been implemented, especially the Health Pact, which established the Regional Management Boards (CGR), space for negotiation and agreement, aimed at regional management. This paper seeks to analyze the role of CGR within the process of regionalization in Mato Grosso. Method: qualitative research, consisting of the exploration of 16 CRG’s already created in state, through the usage of self-administered questionnaires and the study of two different cases – chosen through a polarity criteria – after the analysis of all the data retrieved from said questionnaire. The period of analysis referred to the years 2006 to 2012. The investigation was mainly focused on the conformation of the CGR, its operation, organization and relations – also considering management and planning, seeking to understand how this practice works at the regional level. Results: The early incentive given to the regionalization of health in Mato Grosso strengthened regional bodies (CIB Regional and CGR), having the institutionalization been materialized mainly in regard to its regulatory and normative components. Advances were also made in governance, since under the CGR, interests of individuals, governments and organizations were contemplated and established. However, from the self-administered questionnaire, the analysis of database and through case studies, the limitations of state management coordination and induction process of regionalization of health were highlighted, proving that it affects and compromises the NHS management on the analyzed state.
5

Análisis de la regulación de la competencia de la contraloría general de la república y de las instituciones públicas para iniciar procedimiento administrativo sancionador por infracciones disciplinarias y funcionales

Capani Jurado, Joseph 23 September 2017 (has links)
El trabajo de investigación ha tenido como problema general ¿De qué manera se puede regular la competencia de la Contraloría General de la República y de las Instituciones Públicas para iniciar procedimientos disciplinarios por infracciones disciplinarias? Y la propuesta teórica se basa en que se debe realizar un cambio en la competencia de ambos regímenes utilizando la cooperación y la competencia especial y gradual. / Tesis / Tesis
6

Scalable Schedule-Aware Bundle Routing

De Jonckère, Olivier 09 August 2023 (has links)
This thesis introduces approaches providing scalable delay-/disruption-tolerant routing capabilities in scheduled space topologies. The solution is developed for the requirements derived from use cases built according to predictions for future space topology, like the future Mars communications architecture report from the interagency operations advisory group. A novel routing algorithm is depicted to provide optimized networking performance that discards the scalability issues inherent to state-of-the-art approaches. This thesis also proposes a new recommendation to render volume management concerns generic and easily exchangeable, including a new simple management technique increasing volume awareness accuracy while being adaptable to more particular use cases. Additionally, this thesis introduces a more robust and scalable approach for internetworking between subnetworks to increase the throughput, reduce delays, and ease configuration thanks to its high flexibility.:1 Introduction 1.1 Motivation 1.2 Problem statement 1.3 Objectives 1.4 Outline 2 Requirements 2.1 Use cases 2.2 Requirements 2.2.1 Requirement analysis 2.2.2 Requirements relative to the routing algorithm 2.2.3 Requirements relative to the volume management 2.2.4 Requirements relative to interregional routing 3 Fundamentals 3.1 Delay-/disruption-tolerant networking 3.1.1 Architecture 3.1.2 Opportunistic and deterministic DTNs 3.1.3 DTN routing 3.1.4 Contact plans 3.1.5 Volume management 3.1.6 Regions 3.2 Contact graph routing 3.2.1 A non-replication routing scheme 3.2.2 Route construction 3.2.3 Route selection 3.2.4 Enhancements and main features 3.3 Graph theory and DTN routing 3.3.1 Mapping with DTN objects 3.3.2 Shortest path algorithm 3.3.3 Edge and vertex contraction 3.4 Algorithmic determinism and predictability 4 Preliminary analysis 4.1 Node and contact graphs 4.2 Scenario 4.3 Route construction in ION-CGR 4.4 Alternative route search 4.4.1 Yen’s algorithm scalability 4.4.2 Blocking issues with Yen 4.4.3 Limiting contact approaches 4.5 CGR-multicast and shortest-path tree search 4.6 Volume management 4.6.1 Volume obstruction 4.6.2 Contact sink 4.6.3 Ghost queue 4.6.4 Data rate variations 4.7 Hierarchical interregional routing 4.8 Other potential issues 5 State-of-the-art and related work 5.1 Taxonomy 5.2 Opportunistic and probabilistic approaches 5.2.1 Flooding approaches 5.2.2 PROPHET 5.2.3 MaxProp 5.2.4 Issues 5.3 Deterministic approaches 5.3.1 Movement-aware routing over interplanetary networks 5.3.2 Delay-tolerant link state routing 5.3.3 DTN routing for quasi-deterministic networks 5.3.4 Issues 5.4 CGR variants and enhancements 5.4.1 CGR alternative routing table computation 5.4.2 CGR-multicast 5.4.3 CGR extensions 5.4.4 RUCoP and CGR-hop 5.4.5 Issues 5.5 Interregional routing 5.5.1 Border gateway protocol 5.5.2 Hierarchical interregional routing 5.5.3 Issues 5.6 Further approaches 5.6.1 Machine learning approaches 5.6.2 Tropical geometry 6 Scalable schedule-aware bundle routing 6.1 Overview 6.2 Shortest-path tree routing for space networks 6.2.1 Structure 6.2.2 Tree construction 6.2.3 Tree management 6.2.4 Tree caching 6.3 Contact segmentation 6.3.1 Volume management interface 6.3.2 Simple volume manager 6.3.3 Enhanced volume manager 6.4 Contact passageways 6.4.1 Regional border definition 6.4.2 Virtual nodes 6.4.3 Pathfinding and administration 7 Evaluation 7.1 Methodology 7.1.1 Simulation tools 7.1.2 Simulator extensions 7.1.3 Algorithms and scenarios 7.2 Offline analysis 7.3 Eliminatory processing pressures 7.4 Networking performance 7.4.1 Intraregional unicast routing tests 7.4.2 Intraregional multicast tests 7.4.3 Interregional routing tests 7.4.4 Behavior with congestion 7.5 Requirement fulfillment 8 Summary and Outlook 8.1 Conclusion 8.2 Future works 8.2.1 Next development steps 8.2.2 Contact graph routing
7

Stochastically Constrained Simulation Optimization On Mixed-Integer Spaces

Nagaraj, Kalyani Shankar 27 October 2014 (has links)
We consider the problem of identifying solutions to a stochastic system under multiple constraints. The objective function and the constraints are expressed in terms of performance measures of the system that are observable only via a simulation model parameterized by a finite number of decision variables. In solving for such a system, one faces the much harder challenge of verifying the feasibility of a potential solution. Toward this, we present cgR-SPLINE, a multistart simulation optimization (SO) algorithm on integer spaces. cgR-SPLINE sequentially solves random restarts of a gradient-based local search routine with increasing precision. The local search routine in turn solves progressively stricter outer approximations of the underlying problem. The local solution estimator from a recently ended restart is probabilistically compared against an incumbent solution, thus generating a sequence of global solution estimators. The optimal convergence rate of the solution iterates is observed to be sub-exponential, slower than the exponential rate observed for SO problems on unconstrained discrete spaces. Additionally, efficiency for cgR-SPLINE dictates that the number of multistarts and the total simulation budget be sublinearly related, implying an increased emphasis on exploration than is prescribed in the continuous context. Heuristics for choosing constraint relaxations and solution reporting demonstrate good finite-time performance on three SO problems, of which two are nontrivial. The extension of cgR-SPLINE's framework to mixed spaces seems a natural next step. The presence of infeasible points arbitrarily close to the stochastic boundary, however pose challenges for consistency. We present a general framework for mixed spaces that is very much along the lines of cgR-SPLINE and propose ideas for specific algorithmic refinements and solution reporting. Strategically locating the restarts of a multistart SO algorithm appears to be a largely unexplored research topic. Toward achieving efficiency during the exploration phase, we present ideas for ``antithetically" generating the restarts from probability measures constructed from the SO algorithm's performance trajectory. Asymptotic behavior of the proposed sampling strategy and policies for optimal parameter selection are presently conjectural, but appear promising based on the outcomes of preliminary experiments. / Ph. D.
8

Určování genetické odlišnosti biologických sekvencí DNA / Determination of genetic differences of biological DNA sequences

Sliž, Ladislav Unknown Date (has links)
Work on determining the genetic diversity of biological signal aligning DNA sequences, will address a brief description of the composition of DNA. Following is basic information on the bioinformatics analysis. Then the work will describe the possibility of aligning DNA sequences. Work will focus primarily on global Needleman-Wunsch algorithm and local Smit - Watermanovův algorithm. Furthermore, this work will focus on aligning DNA sequences using methods CGR and FCGR. At the end of the work will describe the practical application of identifying genetic differences by aligning the sequences.
9

Zpracování genomických signálů fraktály / Processing of fractal genomic signals

Nedvěd, Jiří January 2012 (has links)
This diploma project is showen possibilities in classification of genomic sequences with CGR and FCGR methods in pictures. From this picture is computed classificator with BCM. Next here is written about the programme and its opportunities for classification. In the end is compared many of sequences computed in different options of programme.
10

Studies on Regulation of Rat Corpus Luteum Function by Prolactin And Luteinizing Hormone

John, Miya January 2015 (has links) (PDF)
The corpus luteum (CL) is a transient endocrine structure formed from the remnants of an ovulated follicle with the primary purpose of producing progesterone (P4), a hormone vital for the establishment and maintenance of pregnancy. The precise regulation of CL function is essential for normal reproductive cycles and maintenance of early pregnancy. In mammals, the pituitary hormones prolactin (PRL) and luteinizing hormone (LH) function as luteotrophic factors during pregnancy, and these two hormones form a functional luteotrophic complex to control CL function in rodents. The mechanistic underpinnings of the luteotrophic actions of PRL and LH, as well as the interplay between the two hormones are poorly understood, and has been the focus of the current investigation. There are several limitations involved in studying luteal function under cell culture conditions. Hence, in vivo animal models employing dopaminergic receptor agonist, 2-Bromo-α-Ergocryptine Mesylate (CB-154; inhibits pituitary PRL secretion) and GnRH receptor antagonist, cetrorelix (CET; inhibits pituitary LH secretion) have been standardized for purposes of examining the roles of PRL and LH in the regulation of CL structure and function in rats. Administration of CB-154 or CET to pregnant rats caused inhibition of CL function and concomitant loss of conceptuses. The CB-154 treatment induced loss of implants was determined to be the result of inhibition of luteal function, rather than the non-specific effects of CB-154 or requirement of PRL for uterine maintenance of implants. To understand how PRL and LH regulate luteal function, targets of PRL and LH in the rat CL needs to be established; however, this has not been well defined by previous studies. The present study observed that CB-154 induced inhibition of luteal function was gradual in its onset; hence, transcriptional changes of genes involved in steroid genesis were examined. mRNA expression of genes involved in P4 production were found to be down regulated, while 20α-hydroxysteroid dehydrogenate (20α-HSD), a P4 catabolizing enzyme was unregulated by CB-154 treatment. CET treatment also had a similar effect on mRNA expression of steroidogenic genes. Interestingly, mRNA expression of the steroidogenic acute regulatory protein (StAR), a key regulator of steroid genesis was not regulated by CB-154 or CET treatment. The luteolytic factor PGF2α also inhibited CL function in pregnant rats but did not down regulate mRNA expression of StAR. However, examination of phospho-StAR (Ser-195), the activated form of StAR, during CET and PGF2α-induced luteolysis suggested that regulation of StAR in the CL of pregnant rats might primarily be at the level of phosphorylation. PRL has been implicated in maintaining luteal expression of LH/choriogonadotrophin receptor (LH/CGR), the cognate receptor for LH. Hence, the luteotrophic actions of PRL may be indirect, by way of regulating LH signalling. Hence, the importance of the LH/CGR pathway and its regulation were examined. LH/CGR mRNA expression was found to correlate with CL function, with CET and CB-154 treatments resulting in down regulation of LH/CGR mRNA expression. Further, CB-154 treatment down regulated LH/CGR pre-mRNA levels, suggesting a role for PRL in the regulation of LH/CGR transcription. mRNA expression of LRH-1, a constitutively active transcription factor previously reported to be important in CL function was down regulated by both CB-154 and CET treatments and hence correlated with LH/CGR mRNA expression. Further, luciferase assays in HeLA cells transiently expressing LRH-1 suggests its involvement in activating the LH/CGR promoter. Estrogen receptor (ER)-α and ER-β also appear to correlate with LH/CGR expression and may play a role along with LRH-1 in the regulation of LH/CGR mRNA expression in the CL of pregnant rats. To examine mechanisms by which PRL may regulate its downstream targets, pathways employed by PRL in the CL of pregnant rats were analysed. The Akt pathway including downstream targets were down regulated by CB-154 treatment. The pathway was found to be regulated at the level of Akt1 mRNA expression. Hence, actions of PRL may regulate the survival of CL. This study has also made observations of LH playing a similar role in survival of the CL. The results of these studies taken together, shed light on the regulation of CL structure and function by PRL and LH, and provide molecular evidence for the two hormones having similar downstream targets and functioning as a luteotrophic complex in pregnant rats, which could only mean a robust interaction between the signalling pathways employed by the two hormones.

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