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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.
21

Optimizing restoration site selection along the Florida Reef Tract for the coral species Acropora cervicornis and Acropora palmata

King, Samantha 26 April 2019 (has links)
The decline of Acropora cervicornis and Acropora palmata populations and consequent listing as endangered species has prompted the need for restoration. Since financial resources are limited, optimal sites for restoration should not only be environmentally suitable for outplant survival, but also have a greater capacity to replenish surrounding reefs with larvae. However, in Florida coral larval dispersal patterns and reef connectivity remain poorly studied. Here, we measured long term larval survival and competency of A. cervicornis to calibrate a high resolution (100m) biophysical larval dispersal model of Acropora in the Florida Reef Tract (FRT). This model revealed that there is potential connectivity between reefs along the FRT, with most source reefs being located in the southern portion of the reef track, and most sinks in the northern part. The connectivity matrix was used then to develop a metapopulation model accounting for larval dispersal patterns, current and historic habitat for the species, growth, fecundity, and density-dependent post-settlement mortality for A. cervicornis and A. palmata, which allows comparing the capacity of suitable restoration sites to recolonize other reefs through sexual recruitment. Furthermore, it can determine optimal mesoscale spatial scaling and temporal planning of restoration project. We found that there was regional variation in the optimal spatial scaling, due to differences in intra-reginal connectivity and exiting coral cover. We also found that temporally staggering outplanting effort is important in poor environmental conditions. Considering ecological processes in restoration will enhance genetic diversity, hasten coral recovery, and boost resilience across the entire reef system.
22

FAM122A ENSURES CELL CYCLE INTERPHASE PROGRESSION AND CHECKPOINT CONTROL AS A SLiM-DEPENDENT SUBSTRATE-COMPETITIVE INHIBITOR TO THE B55α/PP2A PHOSPHATASE

Wasserman, Jason, 0000-0002-0697-5971 January 2023 (has links)
Protein phosphorylation is a reversible post-translational modification that is critical for the regulation of key cellular processes. It is estimated that two-thirds of all cellular proteins are phosphorylated, with more than 98% of those phosphorylation events occurring on Ser/Thr residues. Protein phosphorylation is mediated by protein kinases and reversed via dephosphorylation by protein phosphatases. Two protein phosphatases, phosphatase 1 (PP1) and Protein phosphatase 2A (PP2A), are thought to account for more than 90% of the total phosphatase activity in eukaryotic cells. PP2A is a highly conserved assortment of heterotrimeric holoenzymes responsible for the dephosphorylation of many regulated phosphoproteins. Substrate recognition and the integration of regulatory cues are mediated by B regulatory subunits that are complexed to the catalytic subunit (C) by a scaffold protein (A). Substrate recruitment of PP2A/B55α, the most abundant PP2A holoenzyme, was thought to be mediated by charge-charge interactions between the surface of B55α and its substrates. Challenging this view, we recently discovered a conserved SLiM (Short Linear Motif) [RK]-V-x-x-[VI]-R in a range of proteins, including substrates such as the retinoblastoma-related protein p107 and TAU (Fowle et al. eLife 2021;10:e63181). Here we report the identification of this SLiM in FAM122A, an inhibitor of B55α/PP2A, and analysis of the associated proteomic datasets that aided in identifying FAM122A, which can assist in the further identification of potential substrates and cellular pathways regulated by this phosphatase. The newly identified conserved SLiM is necessary for FAM122A binding to B55α in vitro and in cells. Computational structure prediction with AlphaFold2 predicts an interaction consistent with the mutational data and supports a mechanism whereby FAM122A uses the ‘SLiM’ in the form of a short α-helix to dock to the B55α top groove. In this model, FAM122A spatially constrains substrate access by occluding the catalytic subunit with a second α-helix immediately adjacent to helix-1. Consistently, FAM122A functions as a competitive inhibitor as it prevents the binding of substrates in in vitro competition assays and the dephosphorylation of CDK substrates by B55α/PP2A in cell lysates. Ablation of FAM122A in human cell lines reduces the rate of proliferation, the progression through cell cycle transitions, and abrogates G1/S and intra-S phase cell cycle checkpoints. FAM122A-KO in HEK293 cells results in the attenuation of CHK1 and CHK2 activation in response to replication stress. Overall, these data strongly suggest that FAM122A is a ‘SLiM’-dependent, substrate-competitive inhibitor of B55α/PP2A that suppresses multiple functions of B55α in the DNA damage response and in timely progression through the cell cycle interphase. In agreement with these findings, ectopic expression of B55α results in the downregulation of 14-3-3σ signaling mediated by ATM and ATR as determined by pathway analysis of phosphoproteomic datasets and a reduction of ATM signaling within the total proteome. Altogether, this work has significantly expanded our understanding of the PP2A/B55 SLiM, resulting from the characterization of FAM122A, a high-affinity substrate inhibitor, and enables future interrogation of novel substrates and signaling networks regulated by PP2A/B55α. / Biomedical Sciences
23

DIETARY SUPPLEMENT WASTEWATER TREATMENT BY BIOLOGICAL METHODS

Hou, Xiangting 12 January 2012 (has links)
No description available.
24

Automatic tag correction in videos : an approach based on frequent pattern mining / Correction automatique d’annotations de vidéos : une approche à base de fouille de motifs fréquents

Tran, Hoang Tung 17 July 2014 (has links)
Nous présentons dans cette thèse un système de correction automatique d'annotations (tags) fournies par des utilisateurs qui téléversent des vidéos sur des sites de partage de documents multimédia sur Internet. La plupart des systèmes d'annotation automatique existants se servent principalement de l'information textuelle fournie en plus de la vidéo par les utilisateurs et apprennent un grand nombre de "classifieurs" pour étiqueter une nouvelle vidéo. Cependant, les annotations fournies par les utilisateurs sont souvent incomplètes et incorrectes. En effet, un utilisateur peut vouloir augmenter artificiellement le nombre de "vues" d'une vidéo en rajoutant des tags non pertinents. Dans cette thèse, nous limitons l'utilisation de cette information textuelle contestable et nous n'apprenons pas de modèle pour propager des annotations entre vidéos. Nous proposons de comparer directement le contenu visuel des vidéos par différents ensembles d'attributs comme les sacs de mots visuels basés sur des descripteurs SIFT ou des motifs fréquents construits à partir de ces sacs. Nous proposons ensuite une stratégie originale de correction des annotations basées sur la fréquence des annotations des vidéos visuellement proches de la vidéo que nous cherchons à corriger. Nous avons également proposé des stratégies d'évaluation et des jeux de données pour évaluer notre approche. Nos expériences montrent que notre système peut effectivement améliorer la qualité des annotations fournies et que les motifs fréquents construits à partir des sacs de motifs fréquents sont des attributs visuels pertinents / This thesis presents a new system for video auto tagging which aims at correcting the tags provided by users for videos uploaded on the Internet. Most existing auto-tagging systems rely mainly on the textual information and learn a great number of classifiers (on per possible tag) to tag new videos. However, the existing user-provided video annotations are often incorrect and incomplete. Indeed, users uploading videos might often want to rapidly increase their video’s number-of-view by tagging them with popular tags which are irrelevant to the video. They can also forget an obvious tag which might greatly help an indexing process. In this thesis, we limit the use this questionable textual information and do not build a supervised model to perform the tag propagation. We propose to compare directly the visual content of the videos described by different sets of features such as SIFT-based Bag-Of-visual-Words or frequent patterns built from them. We then propose an original tag correction strategy based on the frequency of the tags in the visual neighborhood of the videos. We have also introduced a number of strategies and datasets to evaluate our system. The experiments show that our method can effectively improve the existing tags and that frequent patterns build from Bag-Of-visual-Words are useful to construct accurate visual features
25

Neke klase planarnih mreža i intervalno-vrednosni rasplinuti skupovi / Some classes of planar lattices and interval-valued fuzzy sets

Gorjanac Ranitović Marijana 08 April 2015 (has links)
<p>U radu je ispitan sledeći problem: <em>Pod kojim&nbsp;uslovima se može rekonstruisati&nbsp; (sintetisati)&nbsp;intervalno-vrednosni rasplinuti skup iz&nbsp; poznate&nbsp;familije nivo skupova.</em></p><p>U tu svrhu su proučena svojstva mreža&nbsp;intervala za svaki od četiri izabrana mrežna&nbsp;<br />uređenja: poredak po komponentama, neprecizni&nbsp;poredak (skupovna inkluzija), strogi &nbsp;i leksikografski&nbsp;poredak.&nbsp;</p><p>Definisane su i-između i ili-između ravne&nbsp;mreže&nbsp;&nbsp; i ispitana njihova svojstva potrebna za&nbsp;re&scaron;avanje postavljenog problema sinteze za&nbsp;intervalno-vrednosne rasplinute skupove. Za i-između ravne mreže je dokazano da su, u svom&nbsp;konačnom slučaju, slim mreže i dualno, da su ili-između ravne mreže dualno-slim mreže.</p><p>Data je karakterizacija kompletnih konačno&nbsp;prostornih i dualno konačno prostornih mreža.&nbsp;</p><p>Određena je klasa mreža koje se mogu&nbsp;injektivno preslikati u direktan proizvod n&nbsp;<br />kompletnih lanaca tako da su očuvani supremumi i&nbsp;dualno, određena je klasa mreža koje se mogu&nbsp;injektivno preslikati u direktan proizvod n lanaca&nbsp;tako da su očuvani infimumi.&nbsp;</p><p>U re&scaron;avanju problema sinteze posmatrana su&nbsp;dva tipa nivo skupova - gornji i donji nivo skupovi.&nbsp;Potreban i dovoljan uslov za sintezu intervalno-vrednosnog rasplinutog skupa iz poznate familije&nbsp;nivo skupova određen je za mrežu intervala koja je&nbsp;uređena poretkom po komponentama, za oba tipa&nbsp;posmatranih nivo skupova.</p><p>Za mrežu intervala uređenu nepreciznim&nbsp;poretkom, problem je re&scaron;en za donje nivo skupove,&nbsp;dok su za gornje nivo skupove određeni dovoljni&nbsp;uslovi.</p><p>Za mrežu intervala koja je uređena&nbsp;leksikografskim poretkom, takođe su dati dovoljni<br />uslovi i to za oba tipa nivo skupova.&nbsp;</p><p>Za mrežu intervala uređenu strogim poretkom&nbsp;problem nije re&scaron;avan, jer izlazi izvan okvira ovog&nbsp;rada.</p><p><br />Dobijeni rezultati su primenjeni za re&scaron;avanje&nbsp;sličnog problema sinteze za intervalno-vrednosne&nbsp;intuicionističke rasplinute skupove&nbsp; za mrežu&nbsp;intervala uređenu poretkom po komponentama.&nbsp;</p><p>Rezultati ovog istraživanja su od teorijskog&nbsp;značaja u teoriji mreža i teoriji rasplinutih skupova,&nbsp;ali postoji mogućnost za primenu u matematičkoj&nbsp;morfologiji i obradi slika.</p> / <p>In this thesis&nbsp; the following problem was investigated: Under which conditions an interval-valued fuzzy set can be reconstructed from the given family of cut sets.</p><p>We consider interval-valued fuzzy sets as&nbsp; a special type of lattice-valued fuzzy sets and&nbsp; we studied properties of lattices of intervals using four different lattice&nbsp; order: componentwise ordering, imprecision ordering (inclusion of sets), strong and&nbsp;lexicographical ordering.</p><p>We proposed new definitions&nbsp; of meet-between planar and join - between planar lattices, we investigated their properties and used them for solving problem of synthesis&nbsp; in&nbsp; interval-valued fuzzy sets.</p><p>It has been proven that finite meet- between planar lattices and slim lattices are equivalent, and dually:&nbsp;&nbsp;&nbsp; finite join-&nbsp; between planar lattices and dually slim lattices are equivalent.</p><p>Complete finitely&nbsp; spatial lattices and complete dually finitely spatial lattices are fully&nbsp;characterized&nbsp; in this setting. Next, we characterized&nbsp; lattices which can be order<br />embedded into a Cartesian product of&nbsp; n&nbsp; complete chains such that all suprema are preserved under the embedding.</p><p>And dually, we characterized lattices which can be order embedded into a Cartesian product of n complete chains such that all infima are preserved under the embedding.</p><p>We considered two types of cut sets &ndash; upper cuts and lower cuts.</p><p>Solution of the&nbsp; problem of synthesis of interval-valued fuzzy sets are given for lattices of intervals under componentwise ordering for both types of cut sets. Solution of problem of synthesis of&nbsp; interval-valued fuzzy sets&nbsp; are&nbsp; given for lower cuts for lattices of intervals under imprecision ordering.&nbsp; Sufficient conditions are given for lattices of intervals under imprecision ordering and family of upper cuts.</p><p>Sufficient conditions are also given for lattices of intervals under lexicographical ordering.</p><p>The problem of synthesis of interval-valued fuzzy sets for lattices of&nbsp; intervals under strong ordering is beyond the scope of this thesis.</p><p>A similar problem of synthesis of&nbsp; interval-valued intuitionistic fuzzy sets is solved for lattices of intervals under componentwise ordering.</p><p>These results are&nbsp; mostly of theoretical importance in lattice theory and fuzzy sets theory, but also they could&nbsp; be applied in mathematical morphology and in&nbsp; image processing.</p>
26

Are Rock Climbers Crunchy? : Serious Leisure, Place Attachment and Environmental Concern in the Shawangunks

Wilson, William Richard 17 June 2013 (has links)
No description available.
27

Modelos numéricos de vigas mistas de aço e concreto pertencentes a sistemas de pisos mistos de pequena altura em situação de incêndio / Numerical modelling of composite slim floor beams in fire

Rocha, Fábio Martin 08 March 2012 (has links)
Os pisos mistos de baixa altura caracterizam um sistema estrutural em que há a incorporação, parcial ou completa, do perfil metálico (viga de aço) na laje de concreto, promovendo a redução da altura da seção e, consequentemente, o aumento da altura útil do pavimento. A incorporação do perfil de aço na laje de concreto garante revestimento ao aço contra o fogo, melhorando o desempenho da viga de aço frente às ações do fogo. Com a finalidade de avaliar o desempenho térmico e estrutural desta solução construtiva, foram desenvolvidos modelos numéricos das vigas parcialmente revestidas presentes nesse sistema estrutural em duas etapas distintas: Na primeira é realizada a análise térmica bidimensional no pacote computacional DIANA para a obtenção dos campos térmicos nas seções transversais das vigas em questão e, a partir daí, considerá-los em um processador de cálculo de momentos plásticos resistentes em todo o intervalo de tempo analisado, sendo então possível avaliar a perda da capacidade portante da seção em função do tempo de exposição ao fogo. A segunda etapa consiste na criação de modelos numéricos tridimensionais em elementos finitos no pacote computacional DIANA, com o qual é possível obter o comportamento estrutural da viga mista de aço e concreto quando exposta ao incêndio padrão, considerando então os efeitos relativos à inclusão do gradiente de temperatura tais como a perda das propriedades mecânicas, a expansão e a interação entre os materiais. Tendo em vista as funcionalidades do código computacional DIANA, diversos modelos foram construídos procurando atingir a melhor aproximação com os resultados experimentais apresentados na literatura associados ao menor custo computacional possível. Dessa forma, foram analisados casos com (1) interação parcial e total entre o aço e o concreto e com (2) diferentes modelos constitutivos para os materiais em questão. Por fim, os resultados obtidos com a análise numérica a partir do DIANA são comparados com os do método dos momentos plásticos, que por sua vez, apresentam um custo computacional bastante reduzido / Slim floor frames consists on structural system in which the steel beam is completely or partially inserted in a concrete slab, that is usually used in profiled steel decks systems. The main goal of the slim floor systems is to obtain a minimum height of the composite beam section and, consequently, achieve a higher height of the floor or a lower total height of the building. The partial encasement of the steel beam in the concrete slab provides a thermal protection, improving the behavior of the beam when subjected to fire. In order to evaluate the thermal and structural behavior of the slim floor system, numerical models considering partially encased beams, which can be found in the slim floor structures, were created. The numerical evaluation procedure was divided in two steps. In the first step, a two-dimensional thermal analysis is carried out using the general finite-element software TNO DIANA to obtain the temperatures gradient in the cross section during the fire exposure time and then, use the data in a computational code developed in FORTRAN which calculates the bearing capacity, over the exposure time, of the slim floor beams by means of the plastic moment capacity method, using the reduction factors associated to the mechanical properties of the materials presented in Eurocode 4. The second step consists in to develop three-dimensional numerical models using the software TNO DIANA and then obtain the complete structural behavior of the beam when subjected to a fire condition. Another aspect related to the loss of mechanical properties was also considered, such as the thermal expansion and the interaction between the steel and the concrete. In view of the DIANA functions, several models were developed in order to achieve a better approximation, a low computational cost, of some tests results presented in wide world literature. The cases of partial and complete interaction between the materials were analyzed, as well as the different constitutive models for them, so that the results obtained at the two steps were compared, and an evaluation of the methods was done
28

Estudo teórico-experimental da contribuição da armadura para a capacidade resistente de vigas parcialmente revestidas / A theoretical and experimental study of steel bars contribution of the bending capacity of the partially encased composite beams

Cavalcanti, Leandro de Amorim 26 March 2010 (has links)
Este trabalho tem por objetivo investigar a contribuição da armadura para a capacidade resistente de vigas mistas parcialmente revestidas, bem como sua eficiência para promover o comportamento conjunto aço-concreto, imprescindível para a obtenção de vigas mistas. O estudo engloba uma investigação experimental com ensaios de vigas sob flexão em quatro pontos e uma simulação numérica utilizando o pacote computacional DIANA®, visando obter dados do comportamento de vigas mistas parcialmente revestidas com armadura longitudinal. Foram ensaiados quatro modelos de viga mista parcialmente revestida e duas variáveis foram analisadas: taxa de armadura longitudinal no concreto e posição dos conectores tipo pino com cabeça. Os resultados experimentais mostraram a eficiência do conjunto armadura-conector para o aumento da capacidade resistente à flexão e para a promoção da interação aço-concreto. A simulação numérica teve concordância satisfatória com os resultados experimentais obtidos. / This study aims to investigate the contribution of the steel bars to the flexure capacity and to promote the composite behavior in partially encased composite beams. The study includes an experimental investigation of partially encased beams under bending in four points and a numerical simulation using the computer package DIANA® to collect data from the behavior of partially encased composite beams with longitudinal reinforcement. Four models of partially encased composite beams were tested and two variables were analyzed: rate of longitudinal reinforcement in concrete and position of stud bolts. The experimental results showed the efficiency of the junction between reinforcing bars and stud bolt to the increase the bending capacity of the partially encased beam and to obtain the steel-concrete interaction. The numerical simulation has good agreement with the experimental results.
29

Análise teórico-experimental de pisos mistos de pequena altura / Experimental and theorical analysis of composite shallow floors

Friedrich, Juliana Teodoro 13 August 2012 (has links)
O piso misto usual é formado pela laje mista, de aço e concreto, apoiada na mesa superior da viga metálica. No piso misto de pequena altura, a laje mista se apoia na mesa inferior da viga, diminuindo assim a altura total do piso. A forma de aço, utilizada nesse sistema, tende a ser três vezes mais alta, que as formas de aço usuais. No Brasil não há uma forma de aço para uso nos sistemas mistos de pequena altura, comercializada. Este estudo trata do desenvolvimento de uma forma de aço trapezoidal para pisos mistos de pequena altura. Foi desenvolvida uma geometria de forma de aço trapezoidal com mossas estampadas nas laterais. Foram realizados ensaios experimentais com modelos de lajes mistas, confeccionados com a forma de aço desenvolvida no presente estudo. Esses ensaios visaram avaliar a resistência e o comportamento de lajes mistas fabricadas com a forma desenvolvida. A geometria da forma de aço e das mossas apresentaram um bom comportamento frente aos esforços cisalhantes, com resistências comparáveis as formas de aço comercializadas, mostrando que podem ser utilizadas em trabalhos futuros. / The usual composite floor is formed by the composite slab, of steel and concrete, supported on the top flange of the steel beam. On the shallow floor systems, the steel beams are contained within the depth occupied by the floor. The steel form steel used in this composite shallow floor systems is around three times higher than usual forms of steel decking. In Brazil there is not a form of steel for use in shallow floor systems, marketed. This study concerns the development of a steel decking to shallow floor systems. Developed a geometry shape of trapezoidal steel and embossements on the sides. Experimental tests were conducted with composite slabs, made of steel the shape developed in this study. These tests were intended to assess the strength and behavior of composite slabs made with the developed form. The geometry of the steel form and embossements showed good behavior against shearing efforts, forms with resistances comparable steel deckings marketed, showing that may be used in future work.
30

Uma abordagem prática e eficiente de consultas por similaridade para suporte a diagnóstico por imagens. / A pratical and eficient approach of searches for similarity to support diagnose by images.

Rosa, Natália Abdala 26 September 2002 (has links)
O objetivo desse trabalho é apresentar as características de um Sistema de Apoio ao Diagnóstico em Sistema Hospitalar Suportando Busca por Imagens Similares, a ser desenvolvido e implantado no Hospital das Clínicas de Ribeirão Preto. A recuperação de imagens baseada no conteúdo é uma área de pesquisa que tem evoluído bastante nos últimos anos. Assim, um sistema de busca e obtenção de imagens, utilizando tal técnica, deve ser extensível aos novos algoritmos de extração de características e métodos de indexação. A extração de características de imagens, tais como informações de cor, textura, forma e o relacionamento entre elas são utilizadas para descrever o conteúdo das imagens. Essas características são então utilizadas para indexar e possibilitar a comparação de imagens no processo de recuperação. O sistema proposto utilizará um método de indexação de dados recém-desenvolvido – a Slim-tree – para indexar as características extraídas das imagens. Através desse método o Sistema de Apoio ao Diagnóstico possibilitará a consulta por conteúdo em imagens médicas. / This works presents the main characteristics of a diagnosis support system based on image similarity search for medical applications. This system was developed to be used in the Clinical Hospital of Ribeirao Preto of the University of Sao Paulo. The content-based image retrieval (CBIR) researching area has evolved greatly in the last years. Thus, a CBIR system should be able to incorporate the new techniques developed, such as, new feature extraction algorithms and indexing methods among others. Traditionally, the main features extracted from images to get the image essence are color, texture, shape and the relationship among them. Therefore, such features describe the images under analysis, and are used to index and to compare images during the content-based retrieval process. The proposed system takes advantage of a new metric access method - the Slim-tree, which allows the indexing and the retrieval of the images through their extracted features.

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