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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.
191

Modificações esqueletais e apendiculares torácicas para captação de água do solo em caranguejos semiterrestres (Crustacea: Brachyura: Grapsoidea:Ocypodoidea) / Thoracic appendicular and skeletal modifications to capture soil water in semi-terrestrial crabs (Crustacea:Brachyura:Grapsoidea:Ocypodoidea)

Tainá Stauffer de Oliveira 10 October 2014 (has links)
A conquista do ambiente terrestre por caranguejos Brachyura é dependente da obtenção e reserva de água na câmara branquial durante o período de emersão. Uma maneira de se obter água do meio é através de tufos de cerdas hidrofílicas, capazes de captar água do solo por capilaridade. Sabe-se que essas cerdas hidrofílicas estão associadas à abertura de Müller e que a água captada é admitida na câmara branquial graças à diferença de pressão entre a câmara branquial e o meio externo, produzida pelos batimentos do escafognatito. Contudo, as modificações morfológicas esqueletais e apendiculares para a formação da abertura de Müller e a composição das cerdas do tufo não são conhecidos. Com o intuito de elucidar tais lacunas, foram estudados o esqueleto axial, apendicular e a quetotaxia de 22 espécies de caranguejos semiterrestres pertencentes às superfamílias Grapsoidea (Grapsidae, Sesarmidae, Varunidae e Gecarcinidae) e Ocypoidea (Ocypodidae e Ucididae). O estudo do esqueleto axial e apendicular revelou que a abertura de Müller é, na verdade, um canal complexo que pode ser composto por três componentes: o canal pleural, a calha apendicular e o tufo de cerdas. A água presente no substrato é captada pelo tufo de cerdas, é conduzida pela calha apendicular, passa pelo canal pleural para, enfim, ser admitida na câmara branquial. O tufo de cerdas é formado entre a face posterior do coxopodito do pereópode 3 e a face anterior do coxopodito do pereópode 4. Em Sesarmidae, o tufo também ocorre entre os coxopoditos dos pereópodes 2 e 3. Os representantes das superfamílias Grapsoidea e Ocypodoidea diferem quanto à formação do canal de Müller. Os tipos de cerdas presentes nos tufos de cerda associados ao canal de Müller são os mesmos encontrados em outros pereópodes e no bordo da região branquiostegal (cerdas simples, paposas e papo-serradas). A única exceção são as cerdas constritas presentes, exclusivamente, nos tufos de cerdas das espécies da família Ocypodidae. Nos tufos de Grapsoidea, a inserção de cerdas no coxopodito do pereópode 4 ocorre somente na sua porção ventral enquanto, em Ocypodoidea, as cerdas do coxopodito do pereópode 4 se inserem tanto na porção ventral como na porção distal. A calha apendicular pode ser formada entre as coxas dos pereópodes 5/6 ou 6/7, de formato cilíndrico ou semicilíndrico. A função da calha apendicular está associada com a condução da água entre o tufo de cerdas e o canal pleural, embora existam casos de formação do canal de Müller sem a presença da calha apendicular. O canal pleural pode ser aberto ou semitubular, ocorrendo, sempre, entre os pleuritos torácicos 6 e 7 e, em algumas espécies, também entre os pleuritos torácicos 5 e 6. O canal pleural aberto é formado pelo afastamento de dois pleuritos torácicos adjacentes; o canal semitubular é formado pela projeção do pleurito 7 sobre o pleurito torácico 6. Foram encontrados, pelo menos, sete padrões de organização do canal de Müller que variam entre a ausência completa da estrutura até a formação de um canal completo (que apresente tufo de cerdas, calha apendicular e canal pleural, concomitantemente). Ucides cordatus (Ucididae) apresentou modificações esqueletais singulares, bastante diferentes dos demais Ocypodoidea e também de Grapsoidea. As espécies que apresentam maior nível de terrestrialidade (família Gecarcinidae) foram as únicas que não apresentaram canal de Müller ou qualquer adaptação para captação de água do substrato. / The conquest of terrestrial environment by brachyuran crabs depends on the attainment and maintainability of water in the branchial chamber during the emersion period. One way to get environmental water is through tufts of hydrophilic setae, capable of picking up water from the soil by capillarity. It is known that these hydrophilic setae are attached to the Müllers opening and the collected water is admitted into the branchial chamber due to the pressure difference between the branchial chamber and the external environment, produced by the scaphognathite beating. However, the morphological modifications of the axial and appendicular skeleton to form the Müllers opening and the composition of the seta tuft are not known. In order to elucidate such gaps, the axial skeleton, the appendicular skeleton and the chaetotaxy of 22 species of semiterrestrial crabs belonging to superfamilies Grapsoidea (Grapsidae, Sesarmidae, Varunidae and Gecarcinidae) and Ocypodoidea (Ocypodidae and Ucididae) were studied. The study of the axial and appendicular skeleton revealed that the Müllers opening is actually a complex channel that may be comprised of three components: the pleural channel, the appendicular gutter and the setal tuft. The water is collected from the substrate by the setal tuft and carried through the appendicular gutter. Then it passes through the pleural channel to be finally admitted into the branchial chamber. The setal tuft is formed between the posterior face of the coxopodite of pereopod 3 and the anterior face of the coxopodite of pereopod 4. In Sesarmidae species, a second tuft also occurs between the coxopodites of pereopods 2 and 3. Representatives of the superfamilies Grapsoidea and Ocypoidea differ in the formation of Müllers channel. In Grapsoidea tuft, the setal insertion occurs only in the ventral portion of coxopodite of pereopod 4 while in Ocypodoidea, the insertion of these seta occurs both in the ventral and distal portions of coxopodite of pereopod 4. The types of seta which are present in setal tufts associated with the Müllers channel are the same found in other pereopods and in the edge of branchiostegal region (simple, paposes and paposerrate seta). The only exception is the constricted seta which is present exclusively in the setal tufts of Ocypodidae species. The appendicular gutter may be formed between the coxopodites of the 5/6 or 6/7 pereopods, in cylindrical or semi-cylindrical shape. The function of the appendicular gutter is associated with the water conduction between the setal tuft and the pleural channel, although there are cases in which the formation of Müllers channel happens without the presence of the appendicular gutter. Pleural channel can be opened or semitubular. They always occur between thoracic pleurites 6/7 and, in some species, between the thoracic pleurites 5 and 6 as well. The open pleural channel is formed by the spacing of two adjacent thoracic pleurites; the semitubular pleural channel is formed by the projection of pleurite 7 above pleurite 6. At least seven patterns of organization of the Müllers channel were found, ranging from the complete absence of the structure to the formation of a full channel (presenting setal tuft, appendicular gutter and pleural channel concurrently). Ucides cordatus (Ucididae) showed quite unique skeletal modifications, different from the others Ocypodoidea and also from the Grapsoidea. The species with the highest level of terrestriality (Gecarcinidae family) were the only ones who did not have Müllers channel or any adaptation to water abstraction from the substrate.
192

A Positon Based Approach to Ragdoll Simulation

Pascucci, Fiammetta January 2007 (has links)
Create the realistic motion of a character is a very complicated work. This thesis aims to create interactive animation for characters in three dimensions using position based approach. Our character is pictured from ragdoll, which is a structure of system particles where all particles are linked by equidistance constraints. The goal of this thesis is observed the fall in the space of our ragdoll after creating all constraints, as structure, contact and environment constraints. The structure constraint represents all joint constraints which have one, two or three Degree of Freedom (DOF). The contact constraints are represented by collisions between our ragdoll and other objects in the space. Finally, the environment constraints are represented by means of the wall constraint. The achieved results allow to have a realist fall of our ragdoll in the space.
193

A Skeleton Programming Library for Multicore CPU and Multi-GPU Systems

Enmyren, Johan January 2010 (has links)
This report presents SkePU, a C++ template library which provides a simple and unified interface for specifying data-parallel computations with the help of skeletons on GPUs using CUDA and OpenCL. The interface is also general enough to support other architectures, and SkePU implements both a sequential CPU and a parallel OpenMP back end. It also supports multi-GPU systems. Benchmarks show that copying data between the host and the GPU is often a bottleneck. Therefore a container which uses lazy memory copying has been implemented to avoid unnecessary memory transfers. SkePU was evaluated with small benchmarks and a larger application, a Runge-Kutta ODE solver. The results show that skeletal parallel programming is indeed a viable approach for GPU Computing and that a generalized interface for multiple back ends is also reasonable. The best performance gains are received when the computation load is large compared to memory I/O (the lazy memory copying can help to achieve this). We see that SkePU offers good performance with a more complex and realistic task such as ODE solving, with up to ten times faster run times when using SkePU with a GPU back end compared to a sequential solver running on a fast CPU. From the benchmarks we can conclude that skeletal parallel programming is indeed a viable approach for GPU Computing and that a generalized interface for multiple back ends is also reasonable. SkePU does however have some disadvantages too; there is some overhead in using the library which we can see from the dot product and LibSolve benchmarks. Although not big, it is still there and if performance is of uttermost importance, then a hand coded solution would be best. One cannot express all calculations in terms of skeletons either, if one have such a problem, specialized routines must still be created.
194

High Quality Force Field Approximation in Linear Time and its Application to Skeletonization

Brunner, David, Brunnett, Guido 27 April 2007 (has links) (PDF)
Force fields of 3d objects are used for different purposes in computer graphics as skeletonization and collision detection. In this paper we present a novel method to approximate the force field of a discrete 3d object in linear time. Similar to the distance transformation we define a rule that describe how the forces associated with boundary points are propagated into the interior of the object. The result of this propagation depends on the order in which the points of the object are processed. Therefore we analyze how to obtain an order-invariant approximation formula. For a chosen iteration order (i, j, k) the set of boundary points that influence the force of a particular point p of the object can be described by a spatial region Rijk. The geometries of these regions are characterized both for the Cartesian and the body-centered cubic grid (bcc grid). We show that in the case of the bcc grid these regions can be combined in such a way that E3 is uniformly covered which basically means that each boundary point is contained in the same number of regions. Based on the covering an approximation formula for the force field is proposed that has linear complexity and gives good results for standard objects. We also show that such a uniform covering can not be built from the regions of influence of the Cartesian grid. With our method it becomes possible to use features of the force field for a fast and topology preserving skeletonization. We use a thinning strategy on the bcc grid to compute the skeleton and ensure that critical points of the force field are not removed. This leads to improved skeletons with respect to the properties of centeredness and rotational invariance.
195

Age related changes in the post-cranial human skeleton and its implication for the determination of sex

Vance, Veronica Liane Wanek 18 May 2009 (has links)
The study of skeletal differences between males and females has rarely taken into account the physical change in hard tissue characteristics with the onset of advanced age. Anatomical change through degenerative modification may pose a challenge when diagnosing the sex of an unknown individual, especially if age is unknown. The aim of this study was to establish whether sexual dimorphism changes with age. This issue was addressed by using three types of procedural analyses. Firstly, standard measuring techniques were utilized to determine sex from 593 individuals. Visual (morphological) assessment was then performed on 608 individuals using sexually dimorphic traits in the distal humerus and pelvis. Lastly, over 300 individuals were analyzed with geometric morphometries using four locations on the postcranial skeleton. Younger females and males (50 years of age and younger) were then compared to older individuals (over 50 years of age) to determine if sexual dimorphism was increasing or decreasing with the onset of age. Long bone measurements of the postcranial skeleton increased with the onset of age in the most osteoporotic sample (South African white females). Males exhibited an increase in size, mainly in the knee and elbow joints, and black females remained static in their measurements with age. Older white females especially can sometimes incorrectly be misclassified as males. Visual techniques indicated that all populations have similar non-metric morphology in the distal humerus and pelvis. Classification accuracies in females decreased when viewing the distal humerus, indicating a decrease in sexual dimorphism at this location. Females appeared static in their pelvic morphology with the onset of age. Males remained sexually dimorphic throughout life in the humerus and pelvis. Geometric morphometries showed that the morphology of the distal humerus is sexually dimorphic, and does not change with age. Morphometries also confirmed the marked sexual dimorphism in the pelvis, and showed virtually no change in sexual dimorphism when comparing young to old groups. / Thesis (PhD)--University of Pretoria, 2009. / Anatomy / Unrestricted
196

Studies toward the synthesis of the guaianolide skeleton : an intramolecular hetero Diels Alder approach and a carbonyl ene approach

Gambera, Giovanni January 2006 (has links)
This thesis describes the efforts towards the synthesis of the guaiane-6,12-olide skeleton, which characterises the guaianolide family of bioactive natural compounds. Two approaches have been investigated: the intramolecular hetero Diels Alder (IMHDA) reaction and the intramolecular carbonyl ene reaction. This thesis has been divided in three sections: the first part gives a general background about the guaianolides, the second section describes the synthetic approaches we investigated and, finally, the third section reports the experimental details. The first section gives a brief overview about the biosynthesis, the biological activities of the guaianolides, and the most interesting synthetic approaches to obtain them. The second section describes the two different approaches we investigated and gives a theoretical background about the main chemical transformations used. At first, the IMHDA reaction approach is described: a brief overview of palladium catalysis and Diels Alder reaction is given, and it is followed by the results and discussion of our study. Similarly, a theoretical background of the Alder ene reaction is given, before the results and discussion of the intramolecular carbonyl ene reaction approach are described: particular importance is given to the reasoning that led to the assignment of the relative configuration of the cycloadducts obtained, and to the rationalisation of this stereochemical outcome. Finally, the third section gives a complete description of the experimental procedures followed, and of the experimental data for the synthetic studies performed in the previous chapter.
197

Dualités fonctionnelles de GASP-1 et GASP-2, deux protéines multi-domaines antagonistes de la myostatine / Functional duality of GASP-1 and GASP-2, two multi-domain myostatin antagonist proteins

Parente, Alexis 20 September 2019 (has links)
GASP-1 et GASP-2 sont deux protéines très proches structuralement caractérisées par plusieurs modules inhibiteurs de protéases et identifiés comme des inhibiteurs de plusieurs membres de la famille TGF-ß tel que la myostatine ou GDF-11, respectivement régulateurs négatifs de la myogenèse et de l’ostéogénèse. Malgré l’organisation structurale commune des protéines GASPs, leurs profils d’expression différents laissent supposer des rôles physiologiques distincts. C’est pourquoi, nous avons généré des modèles souris Tg(Gasp-1) et Tg(Gasp-2) surexprimant Gasp-1 ou Gasp-2 afin de mieux appréhender les fonctions de ces protéines. Des analyses fonctionnelles, réalisées in vitro et in vivo dans les contextes musculaire, squelettique et anti-protéasique, nous ont permis de mettre en lumière une dualité fonctionnelle entre GASP-1 et GASP-2 dans ces différents contextes. Les deux lignées Tg(Gasp-1) et Tg(Gasp-2) présentent une augmentation de la masse musculaire due à une hypertrophie sans hyperplasie des myofibres. Cependant, les souris Tg(Gasp-1) présentent une dérégulation globale de l’homéostasie du glucose et des défauts métaboliques en vieillissant, phénotype non retrouvé chez les souris Tg(Gasp-2). Ces résultats nous a permis de proposer la protéine GASP-2 comme étant un meilleur candidat thérapeutique dans le cas de maladies musculaires. Dans le contexte squelettique, seule la surexpression de Gasp-2 entraine un phénotype osseux. L’ensemble de nos résultats permet de mettre en évidence un réseau de régulation de l’expression génique des membres de la famille TGF-ß et de leurs inhibiteurs dans le muscle. / GASP-1 and GASP-2 are two closely related proteins structurally characterized by several protease inhibitor modules and identified as inhibitors of several members of the TGF-ß family such as myostatin or GDF-11, negative regulators of myogenesis and osteogenesis, respectively. Despite the common structural organization of GASPs proteins, their different expression profiles suggest distinct physiological roles. We generated Tg(Gasp-1) and Tg(Gasp-2) mouse models overexpressing Gasp-1 or Gasp-2 in order to better understand the functions of these proteins. Functional analyses, carried out in vitro and in vivo in muscular, skeletal and anti-proteasic context, allowed us to highlight a functional duality between GASP-1 and GASP-2 in the different contexts. Both lines Tg(Gasp-1) and Tg(Gasp-2) exhibit an increase in muscle mass due to myofiber hypertrophy without hyperplasia. However, Tg(Gasp-1) mice have an overall deregulation of glucose homeostasis and metabolic defects with age, a phenotype not found in Tg(Gasp-2) mice. These results allowed us to propose the GASP-2 protein as a better therapeutic candidate for muscle diseases. In the skeletal context, only the Gasp-2 overexpression leads to a bone phenotype. Altogether, our findings highlighted a gene expression regulatory network of TGF-ß members and their inhibitors in muscle.
198

Deep Learning Action Anticipation for Real-time Control of Water Valves: Wudu use case

Felemban, Abdulwahab A. 12 1900 (has links)
Human-machine interaction could support many daily activities in making it more convenient. The development of smart devices has flourished the underlying smart systems that process smart and personalized control of devices. The first step in controlling any device is observation; through understanding the surrounding environment and human activity, a smart system can physically control a device. Human activity recognition (HAR) is essential in many smart applications such as self-driving cars, human-robot interaction, and automatic systems such as infrared (IR) taps. For human-centric systems, there are some requirements to perform a physical task in real-time. For human-machine interactions, the anticipation of human actions is essential. IR taps have delay limitations because of the proximity sensor that signals the solenoid valve only when the user’s hands are exactly below the tap. The hardware and electronics delay causes inconvenience in use and water waste. In this thesis, an alternative control based on deep learning action anticipation is proposed. Humans interact with taps for various tasks such as washing hands, face, brushing teeth, just to name a few. We focus on a small subset of these activities. Specifically, we focus on the activities carried out sequentially during an Islamic cleansing ritual called Wudu. Skeleton modality is widely used in HAR because of having abstract information that is scale-invariant and robust against imagery variances. We used depth cameras to obtain accurate 3D human skeletons of users performing Wudu. The sequences were manually annotated with ten atomic action classes. This thesis investigated the use of different Deep Learning networks with architectures optimized for real-time action anticipation. The proposed methods were mainly based on the Spatial-Temporal Graph Convolutional Network. With further improvements, we proposed a Gated Recurrent Unit (GRU) model with Spatial-Temporal Graph Convolution Network (ST-GCN) backbone to extract local temporal features. The GRU process the local temporal latent features sequentially to predict future actions. The proposed models scored 94.14% recall on binary classification to turn on and off the water tap. And higher than 81.58-89.08% recall on multiclass classification.
199

Administrativní budova v Praze / Office building in Prague

Ignatyeva, Anastasia January 2019 (has links)
The content of the diploma thesis is the elaboration of the project documentation for the construction of the administrative building. The building is designed in Prague Holešovice. The administrative building is part of the complexes of three administrative buildings with two common underground floors, which have technical premises and a parking space. On the above floors there are office and commercial premises. The construction system of the building is a reinforced concrete monolithic skeleton. As cladding was used glass facade. The roof of the building is flat.
200

Penzion pro seniory / Retirement home

Homola, Jan January 2019 (has links)
This diploma thesis deals with the project documentation for the execution of the pension for seniors. The land is located in the village of Kozlany. Pension serves long-term accommodation for 30 people. The building has one underground and three above-ground floors. The stop is done with a single-shell surface impermeable roof. The construction is designed as a monolithic skeleton.

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