A major goal of evolutionary developmental biology is to explore mechanisms and events underlying evolution of the myriad body plan morphologies expressed both genetically and phenotypically within the animal kingdom. Arthropods exhibit an astounding array of morphological diversity both within and between representative sub-phyla, thus providing an ideal phylum through which to address questions of body plan innovation and diversification. Major arthropod groups are recognised and defined by the distinct form and number of articulated appendages present along the antero-posterior axis of their segmented bodies. A great deal is known about the developmental genetics of limb development in the model insect Drosophila melanogaster, added to which, much comparative gene expression data and a growing body of functional genetic data is emerging for other arthropod species. Arthropod limb primordia are consistently marked by expression of the homeobox gene Distal-less (Dll), and the focus of this thesis is to compare signalling mediated by early Dll regulatory genes activity along antero-posterior and dorso-ventral embryonic axes during limb specification in Drosophila, with the activity of their orthologs in the widely disparate chelicerate, the spider mite Tetranychus urticae - interpreting new data with that available for other arthropods. Having made a detailed study of spider mite embryonic (and post-embryonic) development, to provide a basis for understanding mRNA transcription and protein activity patterns, I confirmed typical expression of Tetranychus Dll in prosomal limb primordia. I obtained limited results for the candidate antero-posterior positioning genes wingless and engrailed, although one of the two engrailed paralogs I identified is reportedly expressed in posterior segmental compartments, consistent with possible conservation of Engrailed-Wingless interactions in metameric patterning and positive regulation of Dll in arthropod limb specification. In Drosophila, wingless-dependent Dll transcription is restricted along the dorso-ventral axis by dorsal Dpp-mediated and ventral EGFR-mediated signalling gradients. Based on data from Tetranychus and other arthropods, neither dorsal nor ventral signalling regimes appear conserved outside the Drosophila system. Dll suppression in fly abdominal segments occurs due to powerful Hox (Ubx/AbdA) repression of the early Dll cis-regulatory element; this is discussed in relation to the independently evolved limbless chelicerate opisthosoma, informed by hypothetical scenarios of cis (regulatory DNA) and trans (coding sequence) evolution. Given practical difficulties and limitations encountered while working with spider mites, I offer a final assessment of the place of Tetranychus urticae as a non-model, and yet still valuable chelicerate species to consider carrying into the exciting future of evolutionary developmental biology.

Vários estudos têm relatado um aumento da incidência de câncer de pele em todo o mundo. No Brasil, o câncer de pele em geral continua sendo a neoplasia mais incidente em ambos os gêneros. Os tumores de anexos cutâneos compõem um grupo grande de neoplasias que exibem diferenciação morfológica para um dos epitélios anexiais da pele normal. Este trabalho trata dos aspectos clínicos, histológicos e imunoistoquímicos de um tumor anexial de origem folicular: o triquilemocarcinoma e sua versão benigna o triquilemoma. Os objetivos foram analisar comparativamente os dados clínicos, epidemiológicos e a expressão de citoqueratinas 15 e 16, claudinas 1,3,4,5,7 e 11, antígeno CD34, do p63 e do índice de proliferação celular pelo Ki67 entre o grupo dos Triquilemomas e Triquilemocarcinomas diagnosticados na Divisão de Dermatologia do Hospital das Clínicas da Universidade de São Paulo no período de 1991 a 2009 e definir um padrão imunofenotípico que auxilie no diagnóstico diferencial dos dois tumores. O estudo foi feito através de revisão clínico-epidemiológica de prontuário dos casos diagnosticados no período de 1991 a 2009; revisão das lâminas em HE e PAS com e sem diastase; realização das técnicas de imunoistoquímica. No período de 18 anos foram identificados 22 casos válidos de triquilemoma e 16 casos válidos de triquilemocarcinoma. Observou-se uma maior incidência de Triquilemoma entre adultos masculinos enquanto que os Triquilemocarcinomas predominaram entre os idosos femininos. A cabeça foi mais acometida entre os casos benignos que entre os malignos. A opção terapêutica predominante entre os triquilemomas foi de eletrocoagulação e de excisão cirúrgica para os demais casos. A claudina-1, claudina-4 e o CD34 apresentavam medianas mais altas nos casos benignos que nos malignos. Portanto, conclui-se que os dados epidemiológicos e clínicos dos dois grupos de tumores se distinguem em relação à idade, gênero, local de acometimento e tipo de tratamento; observou-se perda de expressão das CL1 e 4 e do CD34, marcadores de diferenciação celular, nos Triquilemocarcinomas em comparação aos Triquilemomas. Por outro lado, o índice de proliferação celular pelo Ki67 mostrou-se um marcador inútil para a distinção entre as formas benigna e maligna / Several studies have been reporting an increasing incidence in skin cancers all over the world. In Brazil, skin cancers are the most prevalent neoplasia in both genders. The skin adnexal tumors are a large group of neoplasias that differentiate into normal skin adnexal epithelium. We report here the clinical, histopathological and immunochemical aspects of the tumors of follicular origin: the trichilemmal carcinoma and its benign variation - trichilemmoma. The objectives were to analise comparatively the clinical and histological data and to compare the expression of the cytokeratins 15 and 16, claudins 1,3,4,5,7 and 11, antigen CD34, p63 and the cell proliferation index in the Ki67 between the two groups, defining a immunophenotypic pattern that could help the differential diagnosis of the two tumors. The study was made by identifying in the hospital records the cases of these tumors between 1991 and 2009. After that, a clinico-epidemiological review was made in the medical records, the histological samples were reviewed to confirm the diagnosis. The best areas were selected to compose the Tissue MicroArray that was used to immunochemical reactions. In these 18 years, there were 22 valid cases of trichilemmoma and 16 of trichilemmal carcinoma. There was a higher incidence of trichilemmoma in male adults and of trichilemmal carcinoma in female elderly. The head was more affected in the benign tumors than in the malignat ones. The treatment option was electrodissection in Trichilemmomas and surgical excision in Trichilemmal carcinomas. Claudin-1, claudin-4 and CD34 were more expressed in the first group. So, we concluded that the clinical and epidemiological data in the two groups differ in age, gender, local of the tumor and treatment option. There was loss of expression of CL1 and 4 and of CD34, cell differentiation markers, in the Trichilemmal carcinoma when compared to the Trichilemmomas. On the other hand, the Ki67 expression was of no use in differentiating the two groups of tumor

Vários estudos têm relatado um aumento da incidência de câncer de pele em todo o mundo. No Brasil, o câncer de pele em geral continua sendo a neoplasia mais incidente em ambos os gêneros. Os tumores de anexos cutâneos compõem um grupo grande de neoplasias que exibem diferenciação morfológica para um dos epitélios anexiais da pele normal. Este trabalho trata dos aspectos clínicos, histológicos e imunoistoquímicos de um tumor anexial de origem folicular: o triquilemocarcinoma e sua versão benigna o triquilemoma. Os objetivos foram analisar comparativamente os dados clínicos, epidemiológicos e a expressão de citoqueratinas 15 e 16, claudinas 1,3,4,5,7 e 11, antígeno CD34, do p63 e do índice de proliferação celular pelo Ki67 entre o grupo dos Triquilemomas e Triquilemocarcinomas diagnosticados na Divisão de Dermatologia do Hospital das Clínicas da Universidade de São Paulo no período de 1991 a 2009 e definir um padrão imunofenotípico que auxilie no diagnóstico diferencial dos dois tumores. O estudo foi feito através de revisão clínico-epidemiológica de prontuário dos casos diagnosticados no período de 1991 a 2009; revisão das lâminas em HE e PAS com e sem diastase; realização das técnicas de imunoistoquímica. No período de 18 anos foram identificados 22 casos válidos de triquilemoma e 16 casos válidos de triquilemocarcinoma. Observou-se uma maior incidência de Triquilemoma entre adultos masculinos enquanto que os Triquilemocarcinomas predominaram entre os idosos femininos. A cabeça foi mais acometida entre os casos benignos que entre os malignos. A opção terapêutica predominante entre os triquilemomas foi de eletrocoagulação e de excisão cirúrgica para os demais casos. A claudina-1, claudina-4 e o CD34 apresentavam medianas mais altas nos casos benignos que nos malignos. Portanto, conclui-se que os dados epidemiológicos e clínicos dos dois grupos de tumores se distinguem em relação à idade, gênero, local de acometimento e tipo de tratamento; observou-se perda de expressão das CL1 e 4 e do CD34, marcadores de diferenciação celular, nos Triquilemocarcinomas em comparação aos Triquilemomas. Por outro lado, o índice de proliferação celular pelo Ki67 mostrou-se um marcador inútil para a distinção entre as formas benigna e maligna / Several studies have been reporting an increasing incidence in skin cancers all over the world. In Brazil, skin cancers are the most prevalent neoplasia in both genders. The skin adnexal tumors are a large group of neoplasias that differentiate into normal skin adnexal epithelium. We report here the clinical, histopathological and immunochemical aspects of the tumors of follicular origin: the trichilemmal carcinoma and its benign variation - trichilemmoma. The objectives were to analise comparatively the clinical and histological data and to compare the expression of the cytokeratins 15 and 16, claudins 1,3,4,5,7 and 11, antigen CD34, p63 and the cell proliferation index in the Ki67 between the two groups, defining a immunophenotypic pattern that could help the differential diagnosis of the two tumors. The study was made by identifying in the hospital records the cases of these tumors between 1991 and 2009. After that, a clinico-epidemiological review was made in the medical records, the histological samples were reviewed to confirm the diagnosis. The best areas were selected to compose the Tissue MicroArray that was used to immunochemical reactions. In these 18 years, there were 22 valid cases of trichilemmoma and 16 of trichilemmal carcinoma. There was a higher incidence of trichilemmoma in male adults and of trichilemmal carcinoma in female elderly. The head was more affected in the benign tumors than in the malignat ones. The treatment option was electrodissection in Trichilemmomas and surgical excision in Trichilemmal carcinomas. Claudin-1, claudin-4 and CD34 were more expressed in the first group. So, we concluded that the clinical and epidemiological data in the two groups differ in age, gender, local of the tumor and treatment option. There was loss of expression of CL1 and 4 and of CD34, cell differentiation markers, in the Trichilemmal carcinoma when compared to the Trichilemmomas. On the other hand, the Ki67 expression was of no use in differentiating the two groups of tumor

No description available.

No description available.

There is a wide variety of tails, fins, scales, riblets and surface coatings, which are used by motile animals in nature. Since organisms currently living on earth have gone through millions of years of evolution, one can expect that their design is optimal for their tasks, including locomotion. However, the exterior of living animals has range of different functions, from camouflage to heat insulation; therefore it is a very challenging task to isolate mechanisms, which are beneficial to reduce the motion resistance of the body. There are two general categories of mechanisms existing in locomotion and flow control. The first is active flow control, when an organism is actively moving some parts or the whole body (exerts energy) in order to modify the surrounding flow field (for example, flapping bird wings). The second is passive flow control, in which an organism has an appendage or a coating, which is not actively controlled (no energy is spent), but is interacting with surrounding flow in a beneficial way. Our aim is to find novel mechanisms for passive flow control. We start by looking at a simple model of an appendage (splitter plate) behind a bluff body (circular cylinder). If a recirculation region forms behind the body, already in this simple system there is a symmetry breaking effect for sufficiently short plates, which passively generates turn and drift of the body. We have found that this effect is caused by the pressure forces in the recirculation region, which pushes the plate away from the vertical in a manner similar to how a straight inverted pendulum falls under the influence of gravity. In order to investigate this symmetry breaking, we developed an extension of the immersed boundary projection method, in which the rigid body dynamics and fluid dynamics are coupled implicitly. The method is capable of solving for particle motion in a fluid for very small density ratios. We also explain our findings by a simple yet quantitative reduced-order model and soap-film experiments. To extend our work, we investigate flow around bodies, which are coated by a porous and elastic material. We have analysed various theoretical approaches to modeling a coating in a continuous manner. We aim to solve the governing equations numerically. We have selected multi-scale expansion approach, of which we present some initial results. / Många djur använder sig av fjäll, päls, hår eller fjädrar för att öka sin förmåga att förflytta sig i luft eller vatten. Evolutionen har främjat ojämna, sträva eller gropiga ytor, vilka har en tendens att minska det totala motståndet som uppstår när en kropp rör sig i vatten eller luft, jämfört med en helt slät och jämn yta.Det finns två kategorier av metoder för manipulering av strömning (så kallad flödeskontroll). Den första är en aktiv metod, där organismer aktivt rör hela eller delar av kroppen (förbrukar energi) för att manipulera omgivande strömningsfält. Den andra metoden är passiv, där organismer har utväxter eller ytbeläggningar som de inte är aktivt har kontroll över (ingen energi förbrukas), men som samverkar med omgivande strömningsfält på ett fördelaktigt sätt. Vårt mål är att hitta nya mekanismer för passiv flödeskontroll.Vi börjar med att studera en enkel modell för hur en utväxt samverkar med en strömmande fluid genom att fästa en platta på en cirkulär cylinder. Om en vak (så-kallad återcirkulationsregion) bildas bakom kroppen, bryts symmetrin i strömningsfältet då plattan är tillräckligt kort. Som en konsekvens av detta roterar kroppen och driver i sidled. Vi visar att detta fenomen orsakas av tryckkrafter i återcirkulationsregionen, som förskjuter plattan från dess vertikala läge. Vi argumenterar att denna mekanism är samma mekanism som får en inverterad pendel att falla under inverkan av gravitation. För att analysera symmetribrytningen, utvecklade vi en numerisk metod (immersed boundary projection method), som implicit kopplar stelkropps- och strömningsdynamik. Med hjälp av denna metod kan vi simulera partiklar i fluider med väldigt låga densitetsskillnader. Våra resultat förklaras även med hjälp av en enkel modell av låg ordning och med hjälp av såphinneexperiment.Som nästa steg i vårt arbete, ämnar vi att studera strömningen kring kroppar som är belagda av tät, porös och elastisk beläggning. Vi har analyserat möjliga tillvägagångssätt för att modellera beläggningar med kontinuumteori. Vi har valt en metod baserad på en flerskalig expansionsmetod, från vilken vi presenterar våra preliminära resultat. / <p>QC 20150119</p>

The data obtained from computational fluid dynamics (CFD) simulations of blood flow in the heart is plentiful, and processing this data takes time and the procedure for that is not straightforward. This project aims to develop a tool that can semi-automatically process CFD simulation data, which is based on 4D flow computed tomography (CT) data, with minimal user input. The tool should be able to time efficiently calculate flow parameters from the data, and automatically create overview images of the flow field while doing so, to aid the user's analysis process. The tool is coded using Python programming language, and the Python scripts are inputted to the application ParaView for processing of the simulation data.  The tool generates 3 chamber views of the heart by calculating three points from the given patient data, which represent the aortic and mitral valves, and the apex of the heart. A plane is generated that pass through these three points, and the heart is sliced along this plane to visualize 3 chambers of the heart. The camera position is also manipulated to optimize the 3 chamber view. The maximum outflow velocity over the cardiac cycle in the left atrial appendage (LAA) is determined by searching in a time range around the maximum outflow rate of the LAA in a cardiac cycle, and finding the highest velocity value that points away from the LAA in this range. The flow component analysis is calculated in the LAA and left ventricle (LV) by seeding particles in each at the start of the cardiac cycle, and tracking these particles forwards and backwards in time to determine where the particles end up and come from, respectively. By knowing these two aspects, the four different flow components of the blood can be determined in both the LAA and LV.  The tool can successfully create 3 chamber views of the heart model from three semi-automatically determined points, at a manipulated camera location. It can also calculate the maximum outflow velocity of the flow field over a cardiac cycle in the LAA, and perform a flow component analysis of the LAA and the LV by tracking particles forwards and backwards in time through a cardiac cycle. The maximum velocity calculation is relatively time efficient and produces results similar to those found manually, yet the output is dependent on the user-defined inputs and processing techniques, and varies between users. The flow component analysis is also time efficient, produces results for the LV that are comparable to pre-existing research, and produces results for the LAA that are comparable to the LVs' results. Although, the extraction process of the LAA sometimes includes part of the left atrium, which impacts the accuracy of the results. After processing each part, the tool creates a single file containing each part's main results for easier analysis of the patient data. In conclusion, the tool is capable of semi-automatically processing CFD simulation data which saves the user time, and it has thus met all the project aims