Dissertations / Theses on the topic 'Rare mamals'

Estimates of animal abundance or density are fundamental quantities in ecology and conservation, but for many species such as rare, small mammals, obtaining robust estimates is problematic. In this thesis, I combine elements of two standard abundance estimation methods, capture-recapture and distance sampling, to develop a method called trapping point transects (TPT). In TPT, a "detection function", g(r) (i.e. the probability of capturing an animal, given it is r m from a trap when the trap is set) is estimated using a subset of animals whose locations are known prior to traps being set. Generalised linear models are used to estimate the detection function, and the model can be extended to include random effects to allow for heterogeneity in capture probabilities. Standard point transect methods are modified to estimate abundance. Two abundance estimators are available. The first estimator is based on the reciprocal of the expected probability of detecting an animal, ^P, where the expectation is over r; whereas the second estimator is the expectation of the reciprocal of ^P. Performance of the TPT method under various sampling efforts and underlying true detection probabilities of individuals in the population was investigated in a simulation study. When underlying probability of detection was high (g(0) = 0:88) and between-individual variation was small, survey effort could be surprisingly low (c. 510 trap nights) to yield low bias (c. 4%) in the two estimators; but under certain situations, the second estimator can be extremely biased. Uncertainty and relative bias in population estimates increased with decreasing detectability and increasing between-individual variation. Abundance of the Key Largo woodrat (Neotoma floridana smalli), an endangered rodent with a restricted geographic range, was estimated using TPT. The TPT method compared well to other viable methods (capture-recapture and spatially-explicit capture-recapture), in terms of both field practicality and cost. The TPT method may generally be useful in estimating animal abundance in trapping studies and variants of the TPT method are presented.

Knowledge of the richness of species that inhabit a particular area is an essential metric for both conservationists and practitioners. Relatively cost-efficient and easily standardized solution has occurred in last the decades with the massive digitalization of photography, the camera trap. Such an independent detector is bias-free in the probability of recording objects passing by and in most cases does not disturb animals. Recent discoveries of new mammal species are proof of this. Moreover, camera traps allow for insight into the otherwise hidden behaviour of even the most timid animals. My interest in photography, endangered animal species and nature conservation has led me to the decision to apply a novel method in practice. Me and my team have focused on three different use-confirmation of the accuracy of capture-recapture population estimates, temporal overlaps of invasive species with its prey and competitors, and first ever camera-trapping species inventory in the Niokolo-Koba National Park. Thanks to personal experiences and contacts from World biodiversity hotspots I was able to successfully employ an approach and carry out field studies. I hope that our results will contribute to the development of effective conservation strategies and the methodology itself.

Bats are the only mammals capable of powered flight. In flight, bats consume up to 20 times more oxygen per hour than under basal conditions. This is twice the increase reported for running mammals of the same body sizes. Birds are the only other group of vertebrate capable of powered flight. By plotting morphological and physiological parameters against body mass for bats, terrestrial mammals, and birds, we can observe to what extent these parameters permit high rates of oxygen delivery necessary for flight. In this study we analyzed basal metabolic rate, heart mass, and hematocrit, and compared how differently they scale in the afore-mentioned groups. We found that larger heart masses are associated with the ability to fly; hematocrit values for birds change markedly with body size, while those for mammals and bats are nearly independent of body size; and that BMR scales differently in all three groups.

La chasse aux trophées, type de chasse récréative dont l'objectif premier est de prélever un trophée d'intérêt, est un sujet très controversé. Cette activité est potentiellement génératrice d'un effet Allee anthropogénique (EAA). Ce processus démographique stipule que la valorisation de la rareté d'une espèce peut stimuler son exploitation et mener à son extinction. L'objectif de ce travail a été de tester le risque d'EAA dans la chasse aux trophées. Nous avons mis en évidence que les espèces rares ont une forte valeur économique dans la chasse aux trophées, quelque soit la taille du trophée, ce qui témoigne d'une demande forte pour ces espèces. Nous avons également montré que le nombre d'importations/exportations de trophées et le nombre de trophées de chasse enregistrés par le Safari Club International s'accroît pour les espèces les plus rares lorsque l'indice de rareté de l'espèce augmente. La chasse aux trophées sur les espèces rares a été proposée comme outil pour financer leur conservation. Cependant, nos résultats valident le risque d'EAA pour ces espèces. De plus, les chasseurs ne semblent pas motivés en priorité par la participation à la conservation de la vie sauvage et le peu de données disponibles sur les populations, la chasse illégale, la corruption et le manque de contrôle rendent possible l'exploitation non durable de ces ressources à forte valeur économique. Néanmoins, la vie sauvage doit apporter des bénéfices économiques pour motiver sa préservation. Ainsi, la chasse aux trophées des espèces rares peut être utilisée pour financer leur conservation mais certaines mesures sont à prendre au préalable pour prévenir leur surexploitation
Trophy hunting, which is a form of recreational hunting with the main objective of collecting a trophy of interest, is a controversial subject. This activity could potentially generate an anthropogenic Allee effect (AAE). This demographic process states that the valuation of rarity could drive rare species exploitation and even lead to their extinction. Our project aims at testing the potential for an AEE in trophy hunting. We demonstrate that rare species have a high financial value, regardless of the trophy size, indicating that there is a high demand for those species. We also show that the number of trophies traded internationally and the number of recorded trophies by the Safari Club International (one of the largest clubs for international trophy hunters in the USA) rises as the degree of rarity (as measured by a rarity index) increases. Trophy hunting of rare species has been proposed as a tool to fund their conservation. However, our results indicate that there is a risk of an AAE for rare species. Furthermore, the combined effects of trophy hunting, illegal hunting, corruption as well as the lack of population knowledge and of management controls have potential to result in the unsustainable exploitation of rare species of high financial value. Nonetheless, trophy hunting has potential to generate strong financial incentives that are necessary for wildlife preservation. Such incentives are only likely to be effective if strict measures are required and enforced to prevent overexploitation of rare trophy species

An important goal of ecological studies is to identify and explain patterns or variation in species assemblages. Ecologists have discovered that global variation in the number of species in an assemblage relates strongly to climate, area, and topographic variability in terrestrial environments. Is the same true for other characteristics of species assemblages? The focus of this thesis is to determine whether species assemblage structure, defined primarily as the body mass frequency distributions and species abundance distributions relate in convergent ways to a set of a few environmental variables across broad spatial scales. First, I found that for mammals and trees most of their geographic variation across North and South America in assemblage structure is statistically related to temperature, precipitation, and habitat heterogeneity (e.g. different vegetation types) in convergent ways. I then examined bird assemblages across islands and continents. Despite the evolutionary and ecological differences between island and continental assemblages, I found that much of the variation in bird assemblage structure depends on temperature, precipitation, land area, and island isolation in congruent patterns in continent and island bird assemblages. Frank Preston modeled species richness based on the total number of individuals and the number of individuals of the rarest species. Building on Preston’s model, Chapter 2 hypothesized that gradients of diversity correlate with gradients in the number of individuals of the rarest species, which in turn are driven by gradients in temperature and precipitation. This hypothesis assumes that species abundance distributions relate to temperature and precipitation in similar ways anywhere in the world. I found that both the number of individuals of the rarest species (m) and the proportion of species represented by a single individual in samples of species assemblages (Φ) were strongly related to climate. Moreover, global variation in species richness was more strongly related to these measures of rarity than to climate. I propose that variation in the shape of the log-normal species abundance distribution is responsible for global gradients of species richness: rare species (reflected in m and Φ) persist better in benign climates. Even though body mass frequency distributions of assemblages show convergent patterns in relation to a set of a few environmental variables, the question remains as to what processes are responsible for creating the geographical variation in the body-size distribution of species. Several mechanisms (e.g. heat conservation and resource availability hypotheses) have been proposed to explain this variation. Chapter 5 tested and found no empirical support for the predictions derived from each of these mechanisms; I showed that species of all sizes occur across the entire temperature gradient. In conclusion, assemblage structure among various taxonomic groups across broad spatial scales relate in similar ways to a set of a few environmental variables, primarily mean annual temperature and mean annual precipitation. While the exact mechanisms are still unknown, I hypothesize several to explain the patterns of convergent assembly. Résumé Un but important de l'écologie est d'identifier et d'expliquer la variation de premier ordre dans les caractéristiques des assemblages d'espèces. Un des patrons ayant déjà été identifié par les écologistes, c'est que la variation mondiale de la richesse en espèces est liée à la variation du climat, de l'aire et de la topographie. Est-ce que d'autres caractéristiques des assemblages d'espèces peuvent être reliées à ces mêmes variables? Le but de cette thèse est de déterminer si la structure des assemblages d'espèces, ici définie comme la distribution des fréquences de masse corporelle ainsi que la distribution d'abondances des espèces, est reliée de manière convergente à un petit ensemble de variables environnementales, et ce, partout dans le monde. D'abord, j'ai déterminé que, pour les mammifères et les arbres, la majorité de la variation géographique dans la structure des assemblages d'espèces est reliée statistiquement à température, précipitation, et l’hétérogénéité du couvert végétal , et ce, de manière convergente pour l'Amérique du Nord et du Sud. Je me suis ensuite penché sur l'assemblage des oiseaux sur les îles et les continents. Malgré les larges différences évolutives et écologiques qui distinguent les îles des continents, je démontre que la majorité de la variation dans la structure des assemblages d'oiseaux dépend de la température, la précipitation, la superficie et l’isolation de façon congruente sur les îles et les continents. Frank Preston a modélisé la richesse en espèces d'une localité, basée sur le nombre total d'individus ainsi que le nombre d'individus de l’espèce la plus rare. En s'appuyant sur les modèles de Preston, Chapître 3 propose une nouvelle hypothèse voulant que les gradients de diversité dépendent des gradients du nombre d'individus de l’espèce la plus rare. Celle-ci dépend des gradients de température et de précipitation. Cette hypothèse repose sur le postulat que la distribution d’abondances des espèces dépend de la température et la précipitation, et ce, de la même manière n’importe où au monde. J’ai mis en évidence que le nombre d’individus de l’espèce la plus rare (m), ainsi que la proportion d’espèces représentées par un individu unique () dans des échantillons locaux étaient fortement reliés au climat. D’ailleurs, la variation globale de la richesse en espèces était plus fortement reliée à ces indices de rareté qu’au climat. Je propose que la variation dans la forme de la distribution log-normale d’abondances d’individus soit responsable des gradients mondiaux de richesse en espèces. En d’autres mots, les espèces rares (indiquées par m et ) persistent mieux dans des climats bénins. Malgré que la distribution des fréquences de masse corporelle des assemblages d'espèces soit liée de manière convergente à seulement quelques variables environnementales, la question demeure à savoir quels processus sont responsables des gradients géographiques de variation en masse corporelle des espèces. Plusieurs mécanismes ont été proposés pour expliquer cette variation. Dans Chapitre 5, j'ai testé les prédictions dérivées de chacun de ces mécanismes sans trouver de support empirique pour aucun. Je démontre aussi que des espèces de toutes tailles se retrouvent sur le gradient de température en entier. En conclusion, la structure des assemblages d'espèces, pour différents groupes taxonomiques et à travers le monde, est liée de façon similaire à un petit nombre de variables environnementales. Bien que les mécanismes soient encore inconnus, j'en propose plusieurs pouvant expliquer ces patrons d'assemblages convergents.

The cheetah (Acinonyx jubatus) has experienced a drastic decline in numbers over the last 20 years globally and is currently listed as vulnerable by the International Union for the Conservation of Nature (IUCN). In South Africa, there are only an estimated 763 free-ranging cheetahs and conflict with humans is arguably the most significant reason for this low number. The aim of my study was to determine the population size and demographic characteristics of the cheetah population within the Timbavati Private Nature Reserve (TPNR), South Africa, and to contribute to a better understanding of cheetah space use and habitat selection. The research was conducted on TPNR between November 2009 and June 2011 and I used a photographic survey to assess cheetah population size and demographic characteristics. Location data was obtained by collaring two adult male cheetahs with GPS/GSM collars and ad hoc sightings data from across the reserve for an adult female with cubs and three adolescent females. A relatively high minimum population density of 4.46 cheetahs/100km² was estimated, signifying a relatively healthy cheetah population. The sex ratio data indicated a higher male to female ratio and an average litter size of three cubs. The relatively high cub survival rate and density is promising in terms of the status of species within the area, as the data denote the success and potential persistence of the species. Cheetah home ranges varied between 20.97km² for the female with cubs and 659.65km² for the younger collared male. Season did not appear to be a determining factor in terms of home range sizes for the three social groups within the TPNR. However, the males did show a slight increase in their home range sizes during the dry season when resources where presumably more widespread. My results indicate that the cheetah is an adaptable species, flexible in behaviour and able to tolerate a variety of habitat types. Such knowledge is fundamental for planning and implementing the effective management and conservation of cheetahs in South Africa.

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O objetivo do presente estudo foi analisar a tendência da mortalidade por câncer de mama e câncer de colo do útero em mulheres residentes no município de Juiz de Fora, Minas Gerais. Para tanto, utilizou-se a série histórica de óbitos do Sistema de Informação sobre Mortalidade (SIM) do Ministério da Saúde. Foram identificados os óbitos que tiveram como causa básica o câncer de mama e o câncer de colo do útero, incluído útero sem outra especificação, ocorridos no período de 1980 a 2006. Foram calculadas taxas anuais de mortalidade específicas por idade e padronizadas pela população mundial. Para análise de tendência, foram utilizados modelos de regressão em que as taxas de mortalidade foram consideradas variáveis dependentes e os anos variáveis independentes. Foram aplicados modelos de regressão polinomial e modelo de regressão linear segmentada (regressão joinpoint). A tendência das taxas de mortalidade foi considerada significativa quando o modelo de regressão polinomial considerado atingiu nível de significância de 5% (p < 0,05). Para regressão linear segmentada, foram utilizadas taxas de mortalidade log-transformadas e a análise estatística, testada por teste de permutação com descrição dos respectivos intervalos de confiança. O câncer de mama foi a principal causa de óbito entre as neoplasias malignas na população de mulheres residentes no município de Juiz de Fora, com a menor taxa anual de mortalidade no ano de 1997, equivalente a 10,0 por 100.000 mulheres e a maior taxa em 1999, 19,6 por 100.000. No mesmo período, para o câncer de colo do útero, foram observadas taxas que variaram de 3,6 no ano de 2003 a 12,5 por 100.000 em 1982. A análise de tendência pelo modelo de regressão polinomial mostrou queda na taxa de mortalidade por câncer de colo do útero (p=0,001) e tendência de crescimento da mortalidade por câncer de mama (p=0,035) ao longo dos anos da série. Por outro lado, a análise por regressão linear segmentada mostrou redução na taxa de mortalidade por câncer de colo do útero até o ano de 2001 com APC -4,2% (IC 95% -6,2: -2,1), com estabilização das taxas nos últimos anos da série, e não mostrou variação de tendência na mortalidade por câncer de mama. O comportamento da mortalidade por câncer de mama e colo do útero no município de Juiz de Fora sugere um processo de transição epidemiológica em andamento, representado por significativas taxas de mortalidade por doenças associadas a melhores condições socioeconômicas como o câncer de mama, e persistência de taxas elevadas por 7 tumores que geralmente guardam relação com a pobreza, como o câncer de colo do útero.
The aim of this study was to analyze the trends in mortality from breast cancer and cancer of the uterine cervix in women of the municipality of Juiz de Fora, Minas Gerais, Brazil. The death time-series of the Mortality Information System (Sistema de Informação Sobre Mortalidade – SIM) of the Brazilian Ministry of Health was used. Deaths having as the basic cause breast cancer and cancer of the uterine cervix, including uterus, part unspecified, occurring during the period 1980-2006, were identified. Age-related annual specific mortality rates were calculated and standardized according to the world population. Regression models, in which mortality rates were considered dependent variables and the years independent variables, were used for analysis of mortality trends. Polynomial regression and segmented linear regression (joinpoint) models were applied. Trends in mortality rate were considered significant when the polynomial regression model reached the 5% significance level (p < 0.05). For segmented linear regression, log-transformed mortality rates and permutation tested statistical analysis with description of the respective confidence intervals were used. Breast cancer was the main cause of death among malignancies in the population of women living in the municipality of Juiz de Fora, with the lowest mortality rate in 1997 (10/100,000) and the highest mortality rate in 1999 (19.6/100,000). During the same period, the mortality rates for cancer of the uterine cervix ranged from 3.6/100,000 in 2003 to 12.5/100,000 in 1982. Trend analysis by the polynomial regression model showed a decrease of mortality due to cancer of the uterine cervix (p=0.001) and an increase of mortality due to breast cancer (p=0.035) throughout the years of the series. On the other hand, segmented linear regression analysis showed a decrease in mortality due to cancer of the uterine cervix until 2001 (APC -4.2%; CI 95% -6.2: -2.1), with stabilization of the rates in the last years of the series, there being no variation in the mortality due to breast cancer. The behavior of the mortality due to breast cancer and cancer of the uterine cervix in the municipality of Juiz de Fora suggests an ongoing process of epidemiological transition, with significant mortality rates due to diseases associated with better socioeconomic conditions, such as breast cancer, and the persistence of high rates of tumors related to poverty, such as cancer of the uterine cervix.

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Alguns estudos sobre o câncer de mama no Brasil indicam que a mortalidade associada a esta doença cresceu nas últimas décadas. Contudo, após verificar que tal crescimento não ocorreu de forma homogênea no território nacional, buscou-se, nesse trabalho, analisar a taxa de mortalidade por câncer de mama nos municípios brasileiros e os fatores associados a esta neoplasia. Foram calculadas taxas de mortalidade, padronizadas por faixa etária, centradas nos anos de 1990, 2000 e 2010. Deste modo, foi possível estimar modelos de regressão, com dados em painel e corte transversal, que permitiram verificar o grau de associação de alguns destes fatores em diferentes períodos e regiões do Brasil. Os resultados indicaram que o crescimento da renda per capita, o aumento da expectativa de vida, a queda no nível de escolaridade, a redução da taxa de fecundidade e menores gastos públicos em saúde poderiam elevar a taxa da mortalidade por câncer de mama. No caso da taxa corrigida por causas mal definidas, apenas a longevidade e os gastos públicos em saúde afetariam a mortalidade pela doença. Constatou-se ainda que a mortalidade por câncer de mama é maior no Sul e no Sudeste e menor no Norte, Nordeste e Centro Oeste, respectivamente. Além disso, as menores taxas de mortalidade são encontradas em cidades com 20 a 100 mil habitantes. Já as maiores ocorreriam tanto nos municípios com mais de 500 mil habitantes quanto naqueles onde a população não chega a 5 mil. A análise de tendência revelou que as regiões brasileiras só não reduziram suas respectivas taxas de mortalidade devido a outros fenômenos vivenciados pelo país, tais como o crescimento da renda, a elevação da expectativa de vida e a diminuição da taxa de fecundidade. Por fim, os dados apresentados sobre o câncer de mama revelaram uma qualidade inferior dos registros de óbitos desta neoplasia nas regiões Norte, Centro-Oeste e Nordeste em comparação ao Sudeste e Sul do país. Entretanto, esta situação melhorou durante o período analisado. Além disso, a diminuição dos óbitos por causas mal definidas parece ter reduzido o impacto deste problema sobre a mortalidade por câncer de mama.
Some researchers have indicated an increase on breast cancer mortality in Brazil in recent decades. However, this growth has not been homogeneous along the national territory. Therefore, this research aimed to analyze the factors associated to mortality rate from breast cancer of Brazilian counties. In order to accomplish this task, mortality rates, standardized by age group, were calculated to each county of Brazil to the years 1990, 2000 and 2010. It allowed us to estimate regression models, with cross-section and panel data, in order to verify the degree of association of these factors to different periods and regions of Brazil. The results revealed that a growth rate of per capita income, an increase of longevity, a decrease in the level of education, a reduction of fertility rates and a reduction of public spending on health could increase the mortality from breast cancer. However, when considering the mortality rate with correction by ill-defined causes, the results indicated that only the longevity and public spending on health would affect mortality. It was also found that mortality is higher in the South and Southeast and it is lower in the North, Northeast and Midwest, respectively. In addition, the lowest mortality rates were found in cities with 20.-100 thousand inhabitants. The highest mortality rates belong both to the big cities, with over 500 thousand inhabitants, as to the small ones, where the population does not reach 5 thousand. The trend analysis showed that Brazilian regions could have reduced their respective mortality rates if other phenomena (such as income growth, increased life expectancy and declining fertility rate) had not happened in Brazil. Finally, the compilation of data on breast cancer still showed a lower level of coverage of this neoplasm in the North, Midwest and Northeast and a higher level in the Southeast and South. However, this situation has improved over the considered period. Moreover, the reduction of deaths coming from ill-defined causes, verified along 1990, 2000 and 2010, appears to have reduced the effect of this problem on mortality from breast cancer.

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Breast cancer is the second most common type of cancer in the world, and the most common among women, affecting men who account for 1% of all cases of the disease. The risk factors of the disease are related to age, endocrine / reproductive history, behavioral / environmental factors, and genetic / hereditary factors. The prognosis of the disease depends on its extension (staging), with greater curative potential when diagnosed at baseline.Among the types of treatment of breast cancer stand out surgery, radiotherapy, chemotherapy, hormone therapy and biological therapy. It is highlighted in the radiotherapy modality, Brachytherapy, which is the application of radiation in a more precise and localized way in the tumor. In this work we will focus on high-grade interstitial brachytherapy dose rate, partial and accelerated breast irradiation (IPAM), which has been shown to have better esthetic results, lower risk of injury from radiation from healthy adjacent tissues, shorter duration of treatment, and low recurrence rates. This is a retrospective, longitudinal, descriptive, analytical study, with a review of medical records of patients diagnosed with breast cancer, stages 0-I-II, between the years 2004 and 2013 who received IPAM using brachytherapy after conservative surgery of the breast at the Radium Institute of Campinas, Campinas-SP, Brazil.This work aims to report and evaluate the viability, acute and chronic toxicity, aesthetic aspects, efficacy and factors related to the use of Partial and Accelerated Breast Irradiation with high dose rate brachytherapy for patients with early stage of breast cancer. In addition to assessing recurrence rates and local control of the disease.
O c?ncer de mama ? o segundo tipo de c?ncer mais comum no mundo,e o mais frequente entre as mulheres, acometendo tamb?m homens que representam 1% do total de casos da doen?a. Os fatores de risco da doen?a est?o relacionados com idade, fatores end?crinos/hist?ria reprodutiva, fatores comportamentais/ambientais e fatores gen?ticos/heredit?rios. O progn?stico da doen?a depende da sua extens?o (estadiamento), com maior potencial curativo quando diagnosticada no in?cio. Entre os tipos de tratamento do c?ncer de mama destacam-se a cirurgia, radioterapia , quimioterapia, hormonioterapia e terapia biol?gica. Apresenta destaque na modalidade radioter?pica, a Braquiterapia, que trata-se da aplica??o de radia??o de forma mais precisa e localizada no tumor. Neste trabalho teremos como enfoque a braquiterapia intersticial de alta taxa de dose, irradia??o parcial e acelerada da mama (IPAM), que vem apresentando melhores resultados est?ticos, menor risco de les?o pela radia??o de tecidos adjacentes saud?veis, menor dura??o do tratamento, e baixas taxas de recorr?ncia. Trata-se de um estudo retrospectivo, longitudinal, descritivo, anal?tico, com revis?o de prontu?rios de pacientes com diagn?stico de c?ncer de mama, est?dios 0-I-II , entre os anos de 2004 e 2013 que receberam IPAM utilizando braquiterapia ap?s a cirurgia conservadora da mama no Instituto do Radium de Campinas, Campinas-SP, Brasil. Tal trabalho objetiva relatar e avaliar a viabilidade, toxicidade aguda e cr?nica, aspectos est?ticos, efic?cia e fatores relacionados com utiliza??o de Irradia??o Parcial e Acelerada da Mama com braquiterapia de alta taxa de dose para pacientes com est?dio inicial de c?ncer de mama. Al?m de avaliar as taxas de recorr?ncia e controle local da doen?a.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Images are relevant sources of information in many areas of science and technology. The processing of such information improves and optimizes its use. The image compression causes the information representation is more efficient, reducing the amount of data required to represent an image. The objective of this study is to evaluate the performance of Fractal Compression technique onto mammograms through an association between the objective criteria, provided by Peak Signal Noise Ration (PSNR); and the subjective criteria, given by visual analysis of an expert physician. Visual analysis was performed comparing mammograms compressed to different extents (compression rate) with the original image, where experts classified the compressed images as unacceptable , acceptable , good or great . In doing so, the optimal compression rate and PSNR values of mammograms was achieved, where images are considered acceptable according to experts. In order to compare the performance of fractal compression technique with another compression method, visual analysis was also done on images compressed by JPEG2000 method.
As imagens são fontes relevantes de informação em diversas áreas da ciência e tecnologia. O processamento dessas informações melhora e otimiza sua utilização. A compressão de imagens faz com que a representação da informação seja mais eficiente, reduzindo a quantidade de dados necessários para representar uma imagem. O objetivo deste trabalho é apresentar a avaliação do desempenho da compressão fractal aplicada a imagens mamográficas, pela combinação entre o critério objetivo, fornecido pela relação sinal ruído de pico (Peak Signal Noise Ratio - PSNR), e o critério subjetivo, especificado pela análise visual de médicos especialistas. A análise visual foi realizada comparando as imagens mamográficas comprimidas com diferentes taxas de compressão e a imagem original. Os especialistas classificaram as imagens comprimidas como \"inaceitável\", \"aceitável\", \"boa\" ou \"ótima\". Dessa maneira, conseguiu-se combinar a taxa de compressão e o valor de PSNR, para que as imagens comprimidas sejam consideradas aceitáveis pelos especialistas. Para avaliar o desempenho da compressão fractal foram realizados testes e análises visuais com as mesmas imagens utilizando o método de compressão JPEG2000.
Mestre em Ciências

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FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais
O câncer de mama é o mais frequente na população feminina mundial e brasileira. No Brasil a estimativa é de aproximadamente 57.120 mil novos casos para 2014. Objetivos: analisar a mortalidade e o fluxo dos óbitos por câncer de mama nas microrregiões de saúde no estado de Minas Gerais, no período de 2008 a 2012, considerando a oferta de serviços especializados em assistência oncológica. Métodos: Trata-se de um estudo ecológico que utilizou os dados de mortalidade (SIM), demográficos (IBGE) e dos estabelecimentos de saúde (CNES). Os óbitos foram corrigidos por causas mal definidas e posteriormente efetuou-se o cálculo das taxas de mortalidade por câncer de mama padronizadas pela população padrão mundial, para o estado de Minas Gerais e suas 77 microrregiões. Os óbitos foram analisados considerando o município de residência e o município de ocorrência sendo construídos os mapas de fluxos que permitem visualizar as distâncias percorridas. Utilizou-se os softwares TABWIN, Terraview, Geoda e Microsoft Excel. Resultados: Foram identificados 5885 óbitos por câncer de mama feminina em Minas Gerais resultando em uma taxa de mortalidade padronizada de 10,3 por 100.000 mulheres. As microrregiões que apresentaram as maiores taxas foram Além Paraíba (17,0/100.000), Belo Horizonte/Nova Lima/Caeté (13,6/100.000) e Juiz de Fora/Lima Duarte/Bom Jardim(13,4/100.000). As menores taxas foram encontradas em Brasília de Minas (2,9/100.000), Pedra Azul (3,3/100.000) e Padre Paraíso (3,3/100.000). A análise do fluxo dos óbitos aponta que os municípios que receberam maior número de pacientes externos foram: Belo Horizonte, Ipatinga, Muriaé, Juiz de Fora e Montes Claros, sendo que 20% dos pacientes percorreram distancias superiores a 150 Km em busca de assistência.
Breast cancer is the most common in the world and Brazilian women. In Brazil, the estimate is approximately 57.12 million new cases in 2014. Objectives: to analyze the mortality and the flow of deaths from breast cancer in health micro-regions in the state of Minas Gerais, from 2008 to 2012, considering the provision of services specialized in cancer care. Methods: This was an ecological study using mortality data (SIM), demographics (IBGE) and health facilities (CNES). Deaths were corrected by ill-defined causes and later made the calculation of mortality rates from breast cancer standardized by the standard world population for the state of Minas Gerais and its 77 micro-regions. Deaths were analyzed in the municipality of residence and the occurrence of the municipality being built maps flows that allow viewing distances. We used the TABWIN software, Terraview, geoda and Microsoft Excel. Results: We identified 5885 deaths from female breast cancer in Minas Gerais resulting in standardized mortality rate of 10.3 per 100,000 women. The regions with the highest rates were Alem Paraíba (17.0 / 100,000), Belo Horizonte / Nova Lima / Caeté (13.6 / 100,000) and Juiz de Fora / Lima Duarte / Bom Jardim (13.4 / 100,000). The lowest rates were found in Brasília de Minas (2.9 / 100,000), Pedra Azul (3.3 / 100,000) and Padre Paraíso (3.3 / 100,000). The analysis of the flow of deaths shows that the municipalities that received the most number of outpatients were: Belo Horizonte, Ipatinga, Muriaé, Juiz de Fora and Montes Claros, and 20% of patients traveled higher distances of 150 km for assistance.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The increased incidence of breast cancer in recent years in developed and developing countries has been the main cause of mortality among women aged 40-59 years old. Advances in cancer treatment have increased the quality and survival of patients, however, the adverse effects arising from the therapeutic regimen are extensive and complex, occurring for cardiovascular complications. The Heart Rate Variability (HRV) is a non-invasive parameter, which can be used to identify phenomena related to nerve modulation of the heart, identifying possible changes in this organ. The present study aimed to assess heart rate variability in women with breast carcinoma and treated with doxorrubicin. It was an analytical, cross-sectional study in Maranhense Institute of Oncology, Hospital Aldenora Bello (IMOAB) in the period between March and August 2014 The sample was non-probabilistic type, with 24 female participants, ranging age between 35 to 59 years, divided into two groups, the first experimental group (EG), composed of women with breast carcinoma treatment and control group (CG), composed of women without breast cancer. For data collection, a 12-lead electrocardiogram for the evaluation of heart rate variability, moment to moment where the RR intervals were recorded during the period was used. The participants remained lying at rest in the supine position, and the electrocardiogram was monitored for 15 minutes. RR, and RMSS SDRR indices were used in the time domain (TD) and the LF, HF and LF/HF components in the frequency domain (FD). The data were compiled by BioEstat 5.0 program. No significant differences in variables between the groups were found in demographic and clinical characteristics. The 12 participants in the experimental group were aged between 35 and 59 years, and of these, 66.7% were between 50-59 years old and 33.3% were 40 years or less. There was a reduction of HRV in the DT and DF in the experimental group. Based on the calculation of the individual dose of doxorubicin based on body surface, were found cumulative doses of doxorubicin, above 400 mg/m2 in all experimental group. Early detection of cardiotoxic effects at the beginning or during treatment may help in choosing strategies that enable the reduction of cardiovascular risk. When used in women with breast carcinoma who used doxorubicin, HRV to detect potential heart problems, direct further research and treatment of these changes, thus contributing to improve the prognosis.
O aumento da incidência de câncer de mama nos últimos anos em países desenvolvidos e em desenvolvimento vem sendo responsável pela principal causa de mortalidade entre as mulheres na faixa etária de 40 a 59 anos de idade. Os avanços no tratamento oncológico aumentaram a qualidade e a sobrevida das pacientes, entretanto, os efeitos adversos oriundo do esquema terapêutico são extensos e complexos, com ocorrência para as complicações cardiovasculares. A Variabilidade da Frequência Cardíaca (VFC) é um parâmetro não invasivo, que pode ser utilizada para identificar fenômenos relacionados à modulação nervosa do coração, identificando possíveis alterações nesse órgão. O presente estudo teve como objetivo avaliar a variabilidade da frequência cardíaca em portadoras de carcinoma mamário submetidas a quimioterapia com doxorrubicina. Tratou-se de um estudo analítico e transversal, realizado no Instituto Maranhense de Oncologia, Hospital Aldenora Bello (IMOAB), no período de março a agosto de 2014. A amostra foi por conveniência, com 24 participantes do sexo feminino, na faixa etária entre 35 a 59 anos, divididas em dois grupos, sendo o primeiro grupo experimental (GE), composto por mulheres portadoras de carcinoma mamário em tratamento e o grupo controle (GC), composto por mulheres sem carcinoma mamário. Para a coleta de dados foi utilizado um eletrocardiograma de 12 derivações para a avaliação da variabilidade da frequência cardíaca, onde foram registrados momento a momento os intervalos R-R durante o período de repouso. As participantes permaneceram deitadas em repouso na posição supina, e o eletrocardiograma foi monitorado por 15 minutos. Foram utilizados os índices RR, SDRR e RMSS no domínio do tempo (DT) e os componentes LF, HF e LF/HF no domínio da frequência (DF). Os dados obtidos foram compilados pelo programa BioEstat 5.0. Não foram encontradas diferenças significativas das variáveis analisadas entre os grupos em relação às características clínicodemográficas. As 12 participantes do grupo experimental estavam na faixa etária entre 35 a 59 anos, sendo que destas, 66,7% tinham entre 50 a 59 anos de idade e 33,3% tinham 40 anos ou menos. Houve redução da VFC no DT e DF no grupo experimental. Baseando-se no cálculo da dose individual de doxorrubicina com base na superfície corporal, foram encontradas doses cumulativas de doxorrubicina, acima de 400mg/m2 em todas as participantes do grupo experimental. A detecção precoce dos efeitos cardiotóxicos no início ou no decorrer do tratamento, pode auxiliar na escolha de estratégias que possibilitem a redução do risco cardiovascular. Quando utilizada em portadoras de carcinoma mamário que fizeram uso de doxorrubicina, a VFC permitirá detectar possíveis alterações cardíacas, direcionar o aprofundamento da investigação e tratamento dessas alterações, contribuindo assim na melhora do prognóstico.

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A neoplasia de mama é responsável pelo maior número de óbitos por câncer em mulheres. O Brasil tem diretrizes para o rastreamento do câncer de mama desde 2004, mas a cobertura populacional continua abaixo do recomendado. Os determinantes sociais que influenciam a cobertura do rastreamento e a sobrevivência ainda são pouco estudados. Propõe-se elaborar um modelo conceitual da determinação social da sobrevivência do câncer de mama em mulheres, baseado em evidências, e aplicar este modelo em estudos epidemiológicos. Propõe-se também investigar a distribuição espacial da cobertura de rastreamento mamográfico nas regiões de saúde do Brasil e os fatores associados. Para elaboração do modelo conceitual, fez-se uma revisão integrativa, com busca sistemática nas bases de dados LILACS e MEDLINE com os descritores de assunto "neoplasias da mama", "análise de sobrevivência" e termos relacionados aos determinantes sociais. Com base neste modelo, estudou-se a sobrevivência em 10 anos de uma coorte de mulheres com câncer de mama acompanhadas em serviço oncológico hospitalar de Juiz de Fora, com setores público e privado. Para investigar a cobertura do rastreamento, fez-se um estudo ecológico de análise espacial em saúde. Existem evidências na literatura de que a posição socioeconômica atual e em etapas anteriores da vida, a condição socioeconômica da área de residência, raça/cor/etnia, características dos serviços de saúde, estilo de vida e suporte psicossocial são determinantes sociais da sobrevivência no câncer de mama; e de que fatores biológicos, como o estadiamento da doença, e as intervenções terapêuticas, são mediadores desta relação. No estudo de sobrevivência, as mulheres de raça/cor negra (HR=2,08; IC95%: 1,48-2,91) e residentes em áreas de menor renda (HR=2,39; IC95%: 1,493,83; comparando o quartil de menor renda com o de maior renda) tiveram pior prognóstico. O principal mediador de raça/cor foi o diagnóstico em estágios mais avançados (proporção mediada=40%; IC95%: 37%-42%), provavelmente por menor acesso ao rastreamento. O estudo ecológico mostrou grandes desigualdades regionais na cobertura de rastreamento mamográfico, com valor mediano de 21,6% e intervalo interquartílico de 8,1% a 37,9%. Comparada com a região Sudeste, as regiões de saúde da região Centro-Oeste tiveram em média uma cobertura 24,0% menor, as da região Norte 13,9% menor e as do Nordeste 11,0% menor. Os fatores associados a uma maior cobertura mamográfica foram o tamanho e a proporção de urbanização da população, menor desigualdade de renda, maior disponibilidade de mamógrafos e radiologistas e maior eficiência no uso dos mamógrafos existentes. Nos modelos de regimes espaciais, a eficiência no uso dos mamógrafos foi o único fator significativo para todas as grandes regiões. O índice de Gini foi significativo no Sul e Sudeste, o tamanho da população no Sul, a razão de radiologistas no Centro-Oeste e a razão de mamógrafos no Norte. Foram evidenciadas iniquidades regionais na cobertura de rastreamento mamográfico e disparidades raciais e sociais na sobrevivência de mulheres com câncer de mama. A melhora do acesso a ações de rastreamento e diagnóstico precoce do câncer de mama pode contribuir de maneira importante para a redução das iniquidades em saúde.
Breast cancer accounts for the highest number of cancer deaths in women. Brazil has had guidelines for screening for breast cancer since 2004, but population coverage remains low and the survival of woman with the disease is lower than in high-income countries. The social determinants of screening coverage and survival from breast cancer are still poorly studied. It is proposed to elaborate a conceptual model of the social determination of the survival of breast cancer in women, based on scientific evidence, and to apply this model in epidemiological studies. It is also proposed to investigate the spatial distribution of mammographic screening coverage in Brazilian health regions and associated factors. For the elaboration of the conceptual model, an integrative review was carried out, with a systematic search in the LILACS and MEDLINE databases with the subject descriptors "breast neoplasms", "survival analysis" and terms related to social determinants. Based on this model, it was studied the survival in 10 years of a cohort of women with breast cancer accompanied at a hospital oncology service in Juiz de Fora, with public and private sectors. To investigate the mammographic screening coverage, an ecological study of spatial analysis in health was made. There is evidence in the literature that current socioeconomic status and in earlier life stages, the socioeconomic conditions of area of residence, race/color/ethnicity, characteristics of health services, lifestyle and psychosocial support are social determinants of survival in breast cancer; and that biological factors, such as staging of the disease, in addition to therapeutic interventions, are mediators of this relationship. In the survival study, women of black race/color (HR = 2.08, 95% CI: 1.48-2.91) and residents in lower income areas (HR = 2.39, 95% CI: 1, 49-3,83, comparing the lowest income quartile with the highest income quartile) had a worse prognosis. The main mediator of race/color was the diagnosis at more advanced stages (mediated proportion = 40%, 95% CI: 37%-42%), probably due to less access to screening. The ecological study showed large regional inequalities in mammographic screening coverage, with a median value of 21.6% and an interquartile range of 8.1% to 37.9%. Compared to the Southeast, the health regions of the Central-West had a 24.4% lower coverage, the North region 13,9% lower and the Northeast 11.0% lower. Factors associated with a greater mammographic coverage were the size and proportion of urbanization of the population, lower income inequality, greater availability of mammography machines and radiologists, and greater efficiency in the use of existing mammography machines. In spatial regime models, efficiency in the use of mammography was the only significant factor for all regions. The Gini index was significant in the South and Southeast, the population size in the South, the ratio of radiologists in the Central-West ant the ratio of mammography machines in the North. Regional iniquities in the coverage of mammographic screening and racial and social disparities in the survival of women with breast cancer were evidenced. Improved access to screening and early diagnosis of breast cancer can contribute significantly to reducing health inequities

Australia has one of the world's worst rates of mammal extinctions, accounting for about one third of the mammal species that have become extinct in the world since 1600 (Burbidge and Manly 2002). Most of these documented declines and extinctions have been concentrated towards mammals in the arid-zone of central Australia. In South Australia (SA), one of the arid-zone species that has undergone substantial declines in range and abundance is the black-footed rock-wallaby, Petrogale lateralis (MacDonnell Ranges race). Animals are now restricted to the Anangu Pitjantjatjara Yankunytjatjara (APY) Lands in the state's far north-west, where there remain two known metapopulations. The decline of this race, which is known as 'warru' by Western Desert Indigenous people, is presumed to have been precipitated by introduced predators. However, in order to exclude other potential causes and establish if recovery is feasible, the current project investigated the ecology of warru in the SA APY Lands. In order to make inferences about the habitat and environmental conditions that best facilitate warru persistence, a modelling approach at multiple spatial scales was used. At a landscape scale, warru presence was correlated to geology, slope, soil type and elevation. At a finer scale, fieldwork established that a number of parameters, including aspect, vegetation, rock complexity and refuges' physical characteristics were important determinants of warru presence and use. The work presents the first analysis of P. lateralis habitat requirements. To establish animals' use of this preferred habitat, the thesis provides preliminary data on warru home range and movement patterns. Unfortunately, catastrophic failure of Global Positioning System collars meant that data were limited to those from one adult female in one month. Nevertheless, during this time, the animal had a larger than expected home range and undertook a number of long-range movements, including a sojourn off the hill. These results have implications for management, including predator and fire management strategies. An investigation of the genetic structure of animals in the three largest-known warru colonies indicated that all colonies are genetically diverse, with levels of heterozygosity approximating expected values. All three also exhibited substantial population structuring, with genetic groups correlating to geographic colonies. However, there was also evidence for sub-structuring being present within one of the colonies and for migration occurring into two colonies, with approximately 5% of sampled individuals having mixed ancestry. An analysis of the parentage of offspring indicated that warru have a polygamous mating structure, although one instance of intra- and inter-year monogamy was also established. Population modelling was used to provide an estimate of the sizes of each of the three studied colonies. Combined with recent aerial survey data, these data suggested that there are likely to be fewer than 200 warru remaining in SA. However, all three colonies showed signs conducive to potential recovery, including high average reproductive rates, even sex ratios and high adult survivorship (>75%). Juvenile survival, however, was significantly lower (51%) and positively correlated with winter rainfall, indicating that access to water is important during the drier winter months. The potential for warru recovery was supported by an analysis of warru blood chemistry in both the wild and captive colonies. The latter was established as part of the recovery program and aimed to produce animals for in-situ supplementation and reintroduction. In 2009, when blood samples were taken, warru colonies did not manifest with results that are indicative of population-wide disease. However, the biochemical parameters of animals in one of the in-situ colonies, 'New Well', suggested some level of nutritional and water stress. This suggests that managers could consider providing warru at New Well with supplementary food and water during drought, and/or using fire to promote vegetational diversity. The study presents the first detailed haematological reference values for P. lateralis and potentially, a methodology for other threatened species recovery programs to follow in order to establish the health of their populations. The current results have implications for management of both the in- and ex-situ warru populations. For example, results pertaining to habitat selection can be used to guide selection of appropriate reintroduction sites. Overall, results indicate that although the extant colonies have small population sizes, the animals therein have high reproductive rates, are not suffering the effects of disease and are genetically diverse. The rock-wallabies' polygamous mating strategy is also likely to continue to facilitate this genetic diversity. Furthermore, although warru have specific habitat preferences, they have the capacity to disperse to surrounding available habitat. Overall, this suggests that, given appropriate management, warru recovery is feasible. Some of these data may also be pertinent for management of P. lateralis in the Northern Territory and Western Australia.
Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2011

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014
Adenoid Cystic Carcinoma (ACC) is a rare malignancy that arises mostly in salivary glands. Although rarely described, it has also been found in the breast. Despite the similarities between ACC in the two locations, these triple negative carcinomas differ in incidence and clinical behavior. In these report we describe six cases of breast ACC that were archived at Serviço de Anatomia Patológica, Instituto Português de Oncologia Francisco Gentil – Lisboa, between 2001 and 2013 and we review the published data about the presentation, treatment and follow-up of this rare cancer type.
O Carcinoma adenóide-cístico (ACC) é um cancro raro encontrado predominantemente nas glândulas salivares. Embora raros, existem casos descritos de ACC da mama. Apesar das semelhanças entre o ACC destas duas localizações, estes cancros triplo negativos apresentam incidência, clínica e prognóstico diferentes. Neste artigo são descritos seis casos de ACC da mama arquivados no Serviço de Anatomia Patológica do Instituto Português de Oncologia Francisco Gentil – Lisboa, entre 2001 e 2013 e é feita uma revisão dos dados publicados acerca da sua apresentação clínica, tratamento e follow-up.

Com a proibição do uso de antibióticos para fins não terapêuticos surgiu a necessidade de procurar novos métodos potenciadores da produção de proteína animal. Os ácidos orgânicos surgem como alternativas aos promotores de crescimento convencionais, uma vez que exercem uma ação antimicrobiana, através da diminuição do pH, promovendo uma melhoria na digestibilidade da proteína, aumento das secreções pancreáticas e efeitos tróficos na mucosa intestinal. Assim, a presente revisão sistemática foi realizada com o objetivo de avaliar o efeito dos ácidos orgânicos no desempenho de crescimento de aves e mamíferos de produção. A pesquisa foi realizada nas bases de dados Pubmed, Web of Science e Scielo entre os meses de outubro de 2020 e abril de 2021. No total 47 estudos cumpriram os critérios de elegibilidade definidos de acordo com a temática em análise Os parâmetros utilizados para comparar os diversos estudos foram o consumo de ração, ganho de peso corporal e taxa de conversão alimentar. No geral, os ácidos orgânicos provaram ser uma estratégia alimentar promissora na indústria pecuária. As associações de ácidos orgânicos mostraram ser mais vantajosas do que o uso do ácido orgânico isoladamente. Na maioria dos estudos, os efeitos dos ácidos orgânicos ficaram aquém dos efeitos dos antibióticos. A falta de consistência na demonstração de evidência do benefício dos ácidos orgânicos pode estar relacionada com variáveis não controladas, como o baixo desafio sanitário nas experiências, a capacidade tampão de ingredientes presentes na dieta, a heterogeneidade da microbiota intestinal e a utilização de outro tipo de agentes antimicrobianos que não os antibióticos nos estudos, podendo conduzir a conclusões não sustentadas sobre os aditivos em estudo. Em conclusão, com base na qualidade dos estudos é possível aferir com evidência científica moderada, um impacto positivo dos ácidos orgânicos no desempenho de crescimento de animais de produção.
With the ban on the use of antibiotics for non therapeutic purposes, there was a need to look for new methods to enhance the production of animal protein. Organic acids appear as alternatives to conventional growth promoters, since they exert an antimicrobial action, by decreasing the pH, promoting an improvement in protein digestibility, increased pancreatic secretions and trophic effects on the intestinal mucosa. Thus, the present systematic review was carried out with the aim of evaluating the effect of organic acids on the growth performance of production birds and mammals. The research was carried out in Pubmed, Web of Science and Scielo databases, between the months of October 2020 and April 2021. A total of 47 studies were completely able to align themselves with the proposed theme. The parameters used to compare the different studies were feed intake, body weight gain and feed conversion ratio. Overall, organic acids have proven to be a promising food strategy in the livestock industry. Organic acid associations proved to be more advantageous than the use of organic acid alone. In most studies, the effects of organic acids fell short of the effects of antibiotics. The lack of consistency in demonstrating evidence of the benefit of organic acids may be related to uncontrolled variables, such as the low sanitary challenge in the experiments, the buffering capacity of ingredients present in the diet, the heterogeneity of the intestinal microbiota and the use of other types of antimicrobial agents other than antibiotics in the studies, which may lead to unsupported conclusions about the additives under study. In conclusion, based on the quality of the studies, it is possible to assess, with moderate scientific evidence, a positive impact of organic acids on the growth performance of farm animals.