Planar cell polarity (PCP) is the organization of cellular characteristics within the plane of a tissue. PCP manifests both structurally, as in the directionality of insect bristles or mammalian skin hair, or dynamically, as in vertebrate neurulation, gastrulation, and oriented cell division in the kidney. Two well-conserved pathways are known to regulate PCP in invertebrates and in vertebrates: the Frizzled/PCP pathway and the Fat-Dachsous (Ft-Ds) pathway. The latter consists of the cadherins Ft and Ds, along with the Golgi kinase Four-jointed (Fj) and the transcriptional co-repressor Atrophin (Atro). Ft and Ds can bind each other, suggesting a mechanism for signal transduction. Fj phosphorylates Ft and Ds, modulating their binding affinities for each other. Atro is proposed to link Ft-Ds signaling with downstream events in the nucleus during eye development. The details of Ft-Ds binding, and the consequences of their interactions with other members of the pathway are poorly understood. In this work, I quantitatively analyzed Ft-Ds pathway mutant clones for their effects on ommatidial polarity in the Drosophila eye. My findings suggest that the Ft-Ds pathway regulates PCP independently of asymmetric cellular accumulation of Ft or Ds. I found that Atro has a position-specific role in regulating polarity in the eye, that Fj dampens clonal polarity signals, and that asymmetric accumulation of the atypical myosin Dachs is not essential for production and propagation of a long-range PCP signal. My observations suggest that Ft and Ds interact to modulate a secondary signal that regulates long-range polarity, that signaling by the Ds intracellular domain is dependent on Ft, and that ommatidial fate specification is genetically separable from long-range signaling.

The problem of custody of children is demanded when the parents, due to separation of spouses or judicial separation, or in the dissolution hypothesis of the consensual marriage, do not live in the same house or in the cases where the parents never cohabited. Granting to the children the fundamental right to live in family, the custody should always take into consideration the welfare of the minor, which is to have the presence of both parents in his life. The jointed custody is the familiar arrangement which gives continuity to the affective boundaries established between the father and the mother, even after the family transformation. The Constitucional Grounds of the jointed custody are the equality principle of genus, of the best interest for the minor and the absolute priority for the child and adolescent. It can be executed with or without housing alternating. The problems faced in its applicability by the parents do not impede its implementation. The jointed custody gives advantages to everybody involved: the parents, children and the judiciary, and finds in the mediation the way to its effectiveness, since it promotes the family participation in the litigation involvement. In spite of the acceptance of this modality of juridical arrangement in the Brazilian juridical ordering, it is still being constructed its acceptance gradually and culture, on the contrary what happens in the compared law, where it is applied frequently. An empirical research proved its operation and necessity that the parents are informed by the law representatives about the existence and advantages of the jointed custody. / O problema da guarda de filhos é cogitado quando os pais, em decorrência da separação de fato ou de direito, ou na hipótese da dissolução de união estável, passam a não conviver sob o mesmo teto ou nos casos em que os pais nunca coabitaram. Garantindo à criança o direito fundamental de conviver em família, a guarda deve sempre atender ao melhor interesse do menor, que é ter a presença de ambos os pais em sua vida. A guarda compartilhada é o arranjo familiar que dá continuidade aos vínculos afetivos estabelecidos entre pais e filhos, estimulando uma co-participação com igualdade de direitos e deveres entre o pai e a mãe, mesmo após a transformação da família. Os fundamentos constitucionais da guarda compartilhada são os princípios da igualdade de gêneros, do melhor interesse do menor e da prioridade absoluta da criança e do adolescente. Pode ser exercida com ou sem alternância de lares. Os problemas enfrentados na sua aplicabilidade pelos pais não impedem a sua implementação. A guarda compartilhada proporciona vantagens para todos os envolvidos: os pais, os filhos e o Judiciário, e encontra na mediação o caminho para sua efetivação, na medida em que promove a participação da família na composição do litígio. Apesar da receptividade dessa modalidade de arranjo no ordenamento jurídico brasileiro, ainda se está construindo de forma gradativa sua aceitação e cultura, ao contrário do que já acontece no direito comparado, onde ela é aplicada com freqüência. Uma pesquisa empírica comprovou a sua operacionalização e a necessidade de que os pais sejam informados pelos operadores do direito da existência e das vantagens da guarda compartilhada.

Neste trabalho são abordados dois aspectos relacionados com modelos físicos fraturados: o primeiro, referido à resistência, é abordado através da avaliação de ensaios triaxiais em modelos fraturados pelo critério empírico de resistência de Hoek-Brown, e por análise numérica através do Código Universal de Elementos Distintos (UDEC). O segundo, referido a modos de ruptura, é abordado através da simulação em termos de deformabilidade e resistência de modelos fraturados e a simulação de taludes de diferentes alturas com o intuito de estudar a influência do tamanho do bloco no modo de ruptura. Ambos aspectos estão baseados nos resultados experimentais de Brown (1970) e de Singh (1997). A influêcia do tamanho do bloco no modo de ruptura foi estudada utilizando RMR89\", levando em consideração a escala do maciço (altura do talude). Através de análises numéricas preliminares e de um processo de retroanálises, foi simulado o comportamento mecânico dos modelos fraturados referidos. A avaliação da resistência aplicando o critério de resistência empírica de Hoek-Brown mostrou resultados coerentes quando comparados com os resultados experimentais de Brown (1970). Através de RMR89\" foi possível observar a influência do tamanho do bloco nos modos de ruptura e na estabilidade dos taludes de diferentes alturas. / This works treats about two aspects related to jointed physical models: one related to strength, by back-analyzing data using the Hoek-Brown criterion by means of numerical analyses with the Universal Distinct Element Code (UDEC). The record refers to failure modes, is analyzed by means of numerical simulations taking into account deformability and strength of jointed physical models, as well as the simulation of slopes in jointed rock masses. Slopes of different heigths and different block sizes were analyzed to investigate scale effects. The analyses were made taking experimental results obtained by Brown (1970) and Singh (1997). The influence of the block size was studied using RMR89\", taking the rock mass scale into consideration. Strength evaluation adopting Hoek-Brown empirical strength criterion proved consistent with Brown\'s model test results. By means of RMR89\" the influence of the block size could be analyzed on failure models and in the stability of slopes with different heights.

A Rolling Dynamic Deflectometer (RDD) is a nondestructive testing device for determining continuous deflection profiles of pavements. Theses deflection profiles can be used more effectively when combined with other data such as pavement thickness, variability in moisture and other subsurface conditions, void detection and pavement right-of-way conditions. Therefore, a new, multi-function pavement testing device has been developed by a joint effort between the Texas Department of Transportation (TxDOT), the Center for Transportation Research (CTR) at the University of Texas at Austin (UT) and the Texas A&M Transportation Institute (TTI) at Texas A&M University. This new device is called the Total Pavement Acceptance Device (TPAD). The objective of TPAD testing is to nondestructively and nonintrusively investigate the structural adequacy of the total pavement system. The multiple functions of the TPAD presently include the following measurement capabilities: (1) rolling dynamic deflectometer (RDD), (2) ground penetrating radar (GPR), (3) global positioning (GPS), (4) pavement surface temperature, (5) digital video imaging of pavement and right-of-way conditions and (6) longitudinal survey offsets from known points through distance measurement (DMI). The TPAD is currently designed to perform continuous measurements at speeds around 2 to 3 mph. The effort in this dissertation is directed at: (1) developing the fourth-generation rolling sensors for faster testing speeds with the TPAD, (2) developing the Jointed Concrete Pavement (JCP) testbed with known and well-documented conditions (3) developing and evaluating the TPAD mobile platform, (4) evaluating the performance of the fourth-generation rolling sensors and refining a field calibration procedure and (5) studying the influence of the longitudinal and transverse joints in Jointed Concrete Pavement on TPAD deflection profile measurements. The first part involved the study of previous research and preliminary testing using the second-generation rolling sensor. Key benefits of the fourth-generation rolling sensor are: (1) reduced rolling noise during the testing, (2) higher signal-to-noise ratio (SNR), and (3) better tracking of the sensor. The second part of this work involved the development of the JCP testbed at the Texas Department of Transportation (TxDOT), Flight Services Facility (FSF) adjacent to the Austin-Bergstrom International Airport (ABIA). The JCP testbed was developed to establish a pavement facility with known and well-documented conditions for use in future research dealing with rigid pavement testing. The third part of this work involved the acceptance testing of the TPAD mobile platform for the RDD deflection measurements. The mobile platform was the one of the key components to develop the new moving pavement testing device. The TPAD mobile platform was developed by modifying a small, off-road vibroseies built by Industrial Vehicle International, Inc. (IVI). Acceptance testing of each of the following components was performed: (1) automated speed control, (2) static loading system and (3) dynamic loading system. The fourth part of this work involved the TPAD deflection measurements at the testbed at the TxDOT FSF. The deflection profiles using the fourth-generation rolling sensors and TPAD were performed at the established testbed. During the performance evaluation testing, the new sensor positioning, towing and raising/lowering system was developed and installed in the TPAD. The fifth part of this study involved the deflection measurement using the TPAD-RDD system on the jointed concrete pavement. This study includes the repeatability of the TPAD deflection measurements, the influence of the proximity to the longitudinal and transverse joints in JCP on TPAD deflection measurements, deflection measurements under different pavement surface temperature, the characteristic of the TPAD-RDD deflections and the comparison between the Falling Weight Deflectometer and TPAD deflection measurement testing. / text

Closely jointed greywacke rock masses are widespread throughout both the North and South Islands of New Zealand and much of New Zealand's infrastructure is constructed upon greywacke rock masses. This thesis deals with determining the rock mass strength of unweathered closely jointed New Zealand greywacke rock masses. Currently, the estimation of rock mass strength and deformability is reasonably well predicted through the use of such empirical failure criteria as the Hoek-Brown failure criterion and empirical expressions to predict deformability. However, previous studies upon predicting the strength and deformability of unweathered closely jointed New Zealand greywacke rock masses has shown that existing empirical methods of determining strength and deformability are unsatisfactory. The problem with predicting rock mass strength and deformability moduli of New Zealand greywacke and the lack of adequate data to calibrate a failure criterion was the starting point for this work. The objective of this thesis was to increase the knowledge of intact and defect properties of closely jointed greywacke, develop reliable rock mass data with which to calibrate a failure criterion and improve the ability to estimate the rock mass strength of greywacke rock masses. A review of existing failure criteria for rock masses was conducted and of these criteria, the Hoek-Brown rock mass failure criteria was selected to calibrate to both the intact rock and rock mass failure data, because of its broad acceptance in the rock mechanics community. A database of greywacke properties was developed based on previous studies upon unweathered greywacke around New Zealand and is attached to the thesis as an Appendix. The database included descriptions of greywacke defect properties and mechanical properties of the intact rock and joints. From this database, inputs could be justified for numerical modelling and later analyses of failure criteria. Records from the construction archives of the Benmore and Aviemore hydroelectric power projects in the South Island of New Zealand were reviewed to obtain information and results from a series of shear tests carried out on unweathered closely jointed greywacke in the 1960s. Data on rock mass strength at failure and rock mass deformability were extracted from these records to assess the predictability of the failure criterion and deformability expressions. Problems experienced during the shear tests at the Aviemore dam site created doubt as to the actual rock mass strengths achieved at failure. The behaviour of these tests was studied using the finite difference code FLAC. The work was aimed at investigating the potential for transfer of shear force between the two concrete blocks sheared in each test and the impact shear force transfer had upon the likely normal stresses beneath each block at failure. The numerical modelling results indicated that a combination of preferential failure occurring in one direction, and doubt in the actual normal load applied to the concrete blocks during testing lead to premature failure in the blocks sheared upstream. The blocks sheared in the opposite direction failed at normal stresses that are reflective of the strength of an unweathered greywacke rock mass, but these results could be explained by failure occurring along defects therefore not satisfying the assumptions of homogeneity typically required of a rock mass failure criterion. The Hoek-Brown failure criterion for intact rock was investigated by fitting it to the largest intact greywacke datasets. For a full set of test data (i.e. including tensile data), the Mostyn & Douglas (2000) variant of the Hoek-Brown failure criterion gave the best fit for a full set of rock mass data. A multiple regression method was developed which improved the fitted curve to intact data in the tensile region and gave the best estimate of tensile strength if no existing lab results for tensile strength were available. These results suggest that the Hoek-Brown failure criterion is significantly limited in its applicability to intact NZ greywacke rock. Hoek-Brown input parameters different to those suggested by Hoek et al (2002) are recommended for using the Hoek-Brown failure criterion for intact NZ greywacke. For closely jointed NZ greywacke rock masses, the results from the shear tests at Aviemore and Benmore were separated into different GSI classes and Hoek-Brown envelopes fitted to the datasets by multiple regression. Revised expressions were proposed for each Hoek-Brown input parameter (mb, s, ab) as a function of the GSI. The resulting revised Hoek-Brown failure envelopes for NZ greywacke offer a significant improvement on the existing criterion used to predict the strength of NZ greywacke intact rock and rock masses. The differences in the behaviour of the reaction blocks that failed before the test blocks and the reduction in rock strength due to sliding along defects from that predicted could be reasoned from recorded observations and the behaviour of the concrete blocks during the shear tests. This study has clearly illustrated the need for continued research in this area. This includes (1) a means of assessing the role of defects upon the shear strength of closely jointed greywacke rock mass into a failure criterion, (2) further modelling of the in-situ shear tests by a discrete element procedure to expressly determine the role of the defect on failure, (3) more testing on rock masses to obtain more data to calibrate a rock mass failure criterion, and (4) more studies on predicting the strength of extremely disturbed rock masses.

Difficult gradient calculations, converging to a local optimum without exploring the design space adequately, too much dependency on the starting solution, lacking capabilities to treat discrete and mixed design variables are the main drawbacks of conventional optimization techniques. So evolutionary optimization methods received significant interest amongst researchers in the optimization area. Genetic algorithms (GAs) and simulated annealing (SA) are the main representatives of evolutionary optimization methods. These techniques emerged as powerful and modern strategies to efficiently deal with the difficulties encountered in conventional techniques, and therefore rightly attracted a substantial interest and popularity. The underlying concepts of these techniques and thus their algorithmic models have been devised by establishing between the optimization task and events occurring in nature. While, Darwin&amp / #8217 / s survival of the fittest theory is mimicked by GAs, annealing process of physical systems are employed to SA. On the other hand, dome structures are among the most preferred types of structures for large unobstructed areas. Domes have been of a special interest in the sense that they enclose a maximum amount of space with a minimum surface. This feature provides economy in terms of consumption of constructional materials. So merging these two concepts make it possible to obtain optimum designs of dome structures. This thesis is concerned with the use of GAs and SA in optimum structural design of dome structures, which range from some relatively simple problems to the problems of increased complexity. In this thesis, firstly both techniques are investigated in terms of their practicality and applicability to the problems of interest. Then numerous test problems taken from real life conditions are studied for comparing the success of the proposed GA and SA techniques with other discrete and continuous optimization methods. The results are discussed in detail to reach certain recommendations contributing to a more efficient use of the techniques in optimum structural design of pin-jointed 3-D dome structures.

Two new three-dimensional rock mass strength criteria are developed in this dissertation by extending an existing rock mass strength criterion. These criteria incorporate the effects of the intermediate principal stress, minimum principal stress and the anisotropy resulting from these stresses acting on the fracture system. In addition, these criteria have the capability of capturing the anisotropic and scale dependent behavior of the jointed rock mass strength by incorporating the effect of fracture geometry through the fracture tensor components. Another significant feature of the new rock mass strength criterion which has the exponential functions (equation 6.7) is having only four empirical coefficients compared to the existing strength criterion which has five empirical coefficients; if the joint sets have the same isotropic mechanical behavior, the number of the empirical coefficients reduces to two in this new strength criterion (equation 6.10). The new criteria were proposed after analyzing 452 numerical modeling results of the triaxial, polyaxial and biaxial compression tests conducted on the jointed rock blocks having one or two joint sets by the PFC3D software version 5. In this research to have several samples with the same properties a synthetic rock material that is made out of a mixture of gypsum, sand and water was used. In total, 20 joint systems were chosen and joint sets have different dip angles varying from 15 to 60 at an interval of 15 with dip directions of 30 and 75 for the two joint sets. Each joint set also has 3 persistent joints with the joint spacing of 42 mm in a cubic sample of size 160 mm and the joints have the same isotropic mechanical behavior. The confining stress combination values were chosen based on the uniaxial compressive strength (UCS) value of the modeled intact synthetic rock. The minimum principal stress values were chosen as 0, 20, 40 and 60 percent of the UCS. For each minimum principal stress value, the intermediate principal stress value varies starting at the minimum principal stress value and increasing at an interval of 20 percent of the UCS until it is lower than the strength of the sample under the biaxial loading condition with the same minimum principal stress value. The new rock mass failure criteria were developed from the PFC3D modeling data. However, since the joint sets having the dip angle of 60 intersect the top and bottom boundaries of the sample simultaneously, the joint systems with at least one of the joint sets having the dip angle of 60 were removed from the database. Thus, 284 data points from 12 joint systems were used to find the best values of the empirical coefficients for the new rock mass strength criteria. λ, p and q were found to be 0.675, 3.16 and 0.6, respectively, through a conducted grid analysis with a high R2 (coefficient of determination) value of 0.94 for the new criterion given by equation 6.9 and a and b were found to be 0.404 and 0.972, respectively, through a conducted grid analysis with a high R2 value of 0.92 for the new criterion given by equation 6.10. The research results clearly illustrate how increase of the minimum and intermediate principal stresses and decrease of the joint dip angle, increase the jointed rock block strength. This dissertation also illustrates how different confining stress combinations and joint set dip angles result in different jointed rock mass failure modes such as sliding on the joints, failure through the intact rock and a combination of the intact rock and joint failures. To express the new rock mass strength failure criteria, it was necessary to determine the intact rock strengths under the same confining stress combinations mentioned earlier. Therefore, the intact rock was also modeled for all three compression tests and the intact rock strengths were found for 33 different confining stress combinations. Suitability of six major intact rock failure criteria: Mohr-Coulomb, Hoek-Brown, Modified Lade, Modified Wiebols and Cook, Mogi and Drucker-Prager in representing the intact rock strength was examined through fitting them using the aforementioned 33 PFC3D data points. Among these criteria, Modified Lade, Modified Mogi with power function and Modified Wiebols and Cook were found to be the best failure criteria producing lower Root Mean Square Error (RMSE) values of 0.272, 0.301 and 0.307, respectively. Thus, these three failure criteria are recommended for the prediction of the intact rock strength under the polyaxial stress condition. In PFC unlike the other methods, macro mechanical parameters are not directly used in the model and micro mechanical parameter values applicable between the particles should be calibrated using the macro mechanical properties. Accurate calibration is a difficult or challenging task. This dissertation emphasized the importance of studying the effects of all micro parameter values on the macro mechanical properties before one goes through calibration of the micro parameters in PFC modeling. Important effects of two micro parameters, which have received very little attention, the particle size distribution and the cov of the normal and shear strengths, on the macro properties are clearly illustrated before conducting the said calibration. The intact rock macro mechanical parameter values for the Young’s modulus, uniaxial compression strength (UCS), internal friction angle, cohesion and Poisson's ratio were found by performing 3 uniaxial tests, 3 triaxial tests and 5 Brazilian tests on a synthetic material made out of a mixture of gypsum, sand and water and the joint macro mechanical parameter values were found by conducting 4 uniaxial compression tests and 4 direct shear tests on jointed synthetic rocks with a horizontal joint. Then the micro mechanical properties of the Linear Parallel Bond Model (LPMB) and Modified Smooth Joint Contact Model (MSJCM) were calibrated to represent the intact rock and joints respectively, through the specific procedures explained in this research. The similar results obtained between the 2 polyaxial experiments tests of the intact rock and 11 polyaxial experimental tests of the jointed rock blocks having one joint set and the numerical modeling verified the calibrated micro mechanical properties and further modification of these properties was not necessary. This dissertation also proposes a modification to the Smooth Joint Contact Model (SJCM) to overcome the shortcoming of the SJCM to capture the non-linear behavior of the joint closure varying with the joint normal stress. Modified Smooth Joint Contact Model (MSJCM) uses a linear relation between the joint normal stiffness and the normal contact stress to model the non-linear relation between the joint normal deformation and the joint normal stress observed in the compression joint normal stiffness test. A good agreement obtained between the results from the experimental tests and the numerical modeling of the compression joint normal test shows the accuracy of this new model. Moreover, another shortcoming associated with the SJCM application known as the interlocking problem was solved through this research by proposing a new joint contact implementation algorithm called joint sides checking (JSC) approach. The interlocking problem occurs due to a shortcoming of the updating procedure in the PFC software related to the contact conditions of the particles that lie around the intended joint plane during high shear displacements. This problem increases the joint strength and dilation angle and creates unwanted fractures around the intended joint plane.

The master’s thesis focuses on suitable design of an ecoduct on the highway D1 near Jihlava. It includes a structural analysis of reinforced concrete strip footings and wooden beams in all phases of construction. The material of the main bearing system is glued laminated timber GL24h. An important part of three-jointed ecoduct wooden arched beams is well-chosen isolation.

[pt] O objetivo deste trabalho foi o de verificar a influência da modificação no campo de tensões ao redor de uma escavação em um maciço rochoso fraturado, observando a ocorrência do fechamento de fraturas e a redução da condutividade hidráulica na região ao redor da escavação. São apresentadas inicialmente as características básicas que devem ser consideradas ao analisar problemas em maciços rochosos fraturados e apontados os possíveis efeitos de uma escavação neste tipo de material. Uma breve revisão bibliográfica mostra alguns tipos de técnicas de análises numéricas disponíveis para simulação de problemas em meios descontínuos, com ênfase no método dos elementos discretos e, em especial, no método dos elementos distintos (DEM), empregado no software UDEC da Itasca Consulting Group Inc., utilizado neste trabalho. As simulações utilizam um acoplamento hidromecânico, onde o maciço é representado por um conjunto de blocos e as descontinuidades são tratadas como contornos dos blocos, sendo o fluxo permitido apenas no interior das fraturas. Foi utilizado um modelo hipotético com escavação circular para validação da modelagem a partir de soluções analíticas presentes na literatura. Além disso, foi realizado um estudo de caso real, de dois túneis localizados em uma importante via na cidade do Rio de Janeiro. A análise paramétrica do problema mostra a influência da modificação de algumas variáveis importantes neste tipo de fenômeno. Por fim, foram analisados os resultados de todos os casos, com suas considerações finais e sugestões para trabalhos futuros. / [en] This work aims to verify the influence of the stress field changing around an excavation in a jointed rock mass, noticing the fracture closure and the hydraulic conductivity decrease in the region surrounding the excavation. At first, the basic characteristics that should be considered in jointed rock masses analyses are presented, pointing out the potential effects caused by excavations in such materials. A brief literature review presents some types of numerical analysis techniques available for discontinuous medium modeling, focusing on the discrete elements methods and, specifically, in the distinct element method (DEM), applied in the UDEC software by Itasca Consulting Group Inc., which was utilized in this work. The simulations make use of a hydromechanical coupling, being the rock mass represented by an assembly of blocks. The water flow takes place among the discontinuities, which are treated as blocks’ boundaries. A hypothetical model was used for modeling validation by comparison with analytical solutions from the literature. Besides that, it was accomplished a real case study of two tunnels located at an important road in Rio de Janeiro city. The parametric analyses of the problem show the influence of changing some important variables in this type of phenomenon. At last, all the results have been discussed, with final considerations and future works suggestions.

No description available.