The objective of this thesis work, is to propose an algorithm to detect the faces in a digital image with complex background. A lot of work has already been done in the area of face detection, but drawback of some face detection algorithms is the lack of ability to detect faces with closed eyes and open mouth. Thus facial features form an important basis for detection. The current thesis work focuses on detection of faces based on facial objects. The procedure is composed of three different phases: segmentation phase, filtering phase and localization phase. In segmentation phase, the algorithm utilizes color segmentation to isolate human skin color based on its chrominance properties. In filtering phase, Minkowski addition based object removal (Morphological operations) has been used to remove the non-skin regions. In the last phase, Image Processing and Computer Vision methods have been used to find the existence of facial components in the skin regions.This method is effective on detecting a face region with closed eyes, open mouth and a half profile face. The experiment’s results demonstrated that the detection accuracy is around 85.4% and the detection speed is faster when compared to neural network method and other techniques.

Multimedia retrieval systems are very important today with millions of content creators all over the world generating huge multimedia archives. Recent developments allows for content based image and video retrieval. These methods are often quite slow, especially if applied on a library of millions of media items. In this research a novel image retrieval method is proposed, which utilizes spatial metadata on images. By finding clusters of images based on their geographic location, the spatial metadata, and combining this information with existing content- based image retrieval algorithms, the proposed method enables efficient presentation of high quality image retrieval results to system users. Clustering methods considered include Vector Quantization, Vector Quantization LBG and DBSCAN. Clustering was performed on three different similarity measures; spatial metadata, histogram similarity or texture similarity. For histogram similarity there are many different distance metrics to use when comparing histograms. Euclidean, Quadratic Form and Earth Mover’s Distance was studied. As well as three different color spaces; RGB, HSV and CIE Lab.

Redeye artifact is the most prevalent problem in the flash photography, especially using compact cameras with built-in flash, which bothers both amateur and professional photographers. Hence, removing the affected redeye pixels has become an important skill. This thesis work presents a completely automatic approach for the purpose of redeye detection and removal and it consists of two modules: detection and correction of the redeye pixels in an individual eye, detection of two red eyes in an individual face.This approach is considered as a combination of some of the previous attempts in the area of redeye removal together with some minor and major modifications and novel ideas. The detection procedure is based on the redness histogram analysis followed by two adaptive methods, general and specific approaches, in order to find a threshold point. The correction procedure is a four step algorithm which does not solely rely on the detected redeye pixels. It also applies some more pixel checking, such as enlarging the search area and neighborhood checking, to improve the reliability of the whole procedure by reducing the image degradation risk. The second module is based on a skin-likelihood detection algorithm. A completely novel approach which is utilizing the Golden Ratio in order to segment the face area into some specific regions is implemented in the second module. The proposed method in this thesis work is applied on more than 40 sample images; by considering some requirements and constrains, the achieved results are satisfactory.

Three interrelated genes postulated to affect economically important traits related to growth and/or carcass quality of beef cattle were chosen to characterize and perform association analyses for this study. Melanocortin 1 receptor (MC1R), melanocortin 4 receptor (MC4R) and agouti related protein (AGRP) play an integral role in the appetite pathway and in fat deposition.<p> We genotyped 328 crossbred steers of various coat colours that were purchased at weaning and fed until slaughter for the previously published alleles ED, E+ and e. The E+ allele was present at five percent in this population and therefore was not included in further analysis. Black cattle of ED/ED or ED/e genotype had increased backfat (P<0.05) and required significantly fewer days (15-25) (P<0.01) on feed to reach a target fat level for slaughter compared to the red cattle. Red cattle of e/e genotype were found to have significantly larger longissimus dorsi (l. dorsi) area, shipping weight and hot carcass weight. Subsequent analysis revealed that the differences were comparable whether black versus red coat colour or MC1R genotype was used as the criteria for the group of cattle.<p> MC4R sequence was obtained from 20 random crossbred steers. In addition to several previously published polymorphisms, a novel Ser330Asn polymorphism was detected. A population of 382 crossbred Canadian steers and 985 crossbred American steers was genotyped for this Ser330Asn polymorphism. A minor allele frequency of 0.01 was observed in the Canadian and 0.02 in the American steer populations. No homozygous g.989AA cattle were detected. In the Canadian population, heterozygous steers had increased grade fat (P=0.036) and decreased lean meat yield (P=0.032). Similarly in the American population, steers of the g.989GA genotype had increased backfat (P=0.031) and less desirable yield grades (P=0.022,) but also lower ribeye area measurements (P=0.031). These results suggest that genotyping for the Ser330Asn polymorphism may lead to increased quality of carcasses either through lean meat production or backfat measurements, depending on the goal of the beef operation.<p> Sequence data obtained from 38 Bos taurus beef cattle, 4 Holsteins and 4 Bos indicus cattle revealed six polymorphisms in the AGRP gene. No polymorphisms that altered amino acids were detected in Bos taurus cattle. Genotyping of 382 crossbred beef steers was performed for two polymorphisms, an intronic deletion (g.439_440delTC) and a base pair substitution in exon 4 that did not alter an amino acid (g.715G>A). An ANOVA analysis, using PROC Mixed, was performed for both polymorphisms on several growth and carcass traits. No significant differences were observed.<p> Polymorphisms in MC1R and MC4R could be used as genetic tests which may be beneficial for beef producers in North America. The significant differences observed in this study in relation to cattle growth and fat deposition would represent savings for producers when used for sorting feedlot cattle or in selection of breeding cattle.

<p>Evolution can be studied at many levels, from phenotypic to molecular, and from a variety of disciplines. An integrative approach can help provide a more complete understanding of the complexities of evolutionary change. This dissertation examines the ecology, genetics, and molecular mechanisms of the evolution of floral anthocyanin pigmentation in four species of <em>Mimulus</em> native to central Chile. Anthocyanins, which create red and purple colors in many plants, are a valuable model for studying evolutionary processes. They are ecologically important and highly variable both within and between species, and the underlying biosynthetic pathway is well characterized. The focus of this dissertation is dramatic diversification in anthocyanin coloration, in four taxa that are closely related to the genomic model system <em>M. guttatus</em>. I posed three primary questions: (1) Is floral diversification associated with pollinator divergence? (2) What is the genetic basis of the floral diversification? (3) What is the molecular mechanism of the increased production of anthocyanin pigment? The first question was addressed by evaluating patterns of pollinator visitation in natural populations of all four study taxa. The second question was explored using segregation analysis for a series of inter- and intraspecific crosses. One trait, increased petal anthocyanins in <em>M. cupreus</em>, was further dissected at the molecular level, using candidate gene testing and quantitative gene expression analysis. Pollinator studies showed little effect of flower color on pollinator behavior, implying that pollinator preference probably did not drive pigment evolution in this group. However, segregation analyses revealed that petal anthocyanin pigmentation has evolved three times independently in the study taxa, suggesting an adaptive origin. In addition to pollinator attraction, anthocyanins and their biochemical precursors protect against a variety of environmental stressors, and selection may have acted on these additional functions. Molecular analysis of petal anthocyanins in <em>M. cupreus</em> revealed that this single-locus trait maps to a transcription factor, <em>McAn1</em>, which is differentially expressed in high- versus low-pigmented flowers. Expression of the anthocyanin structural genes is tightly correlated with <em>McAn1</em> expression. The results suggest that <em>M. cupreus</em> pigmentation evolved by a mutation cis to <em>McAn1</em> that alters the intensity of anthocyanin biosynthesis.</p> / Dissertation

<p>One of the major goals of evolutionary biology is understanding the process of species formation. There is particular interest in how selection can favor species formation through the process of reinforcement. When two diverging taxa produce maladaptive hybrids, selection will favor greater reproductive isolation between the taxa. Reinforcement often results in a pattern of reproductive character displacement, which is defined as two species having greater reproductive isolation in sympatry then in allopatry. Floral-color divergence in the native Texas wildflower, Phlox drummondii, constitutes one of the best documented cases of reinforcement in plants. P. drummondii and a closely related species, P. cuspidata produce similar light-blue flowers throughout the allopatric parts of their ranges. However, in the area of sympatry P. drummondii has dark-red flowers, which has been shown to decrease hybridization between the two species. In the following work, I investigate the causes and consequences of the process of reinforcement and the pattern of character displacement in P. drummondii. First, I identify the genetic basis of the flower color variation as regulatory changes in two genes controlling the type and amount of anthocyanin floral pigments. I then evaluate neutral genetic variation across the range of P. drummondii and conclude there is extensive gene flow between allopatric and sympatric areas of the range, which indicates that selection and not genetic drift is responsible for the flower color variation. By investigating genetic variation at the loci underlying flower color variation I find a molecular signature of a selective sweep at one of the two flower color loci, further indicating that selection is responsible for this flower color variation. Finally, I measure selection on flower color in both sympatry and allopatry. I find no evidence that flower color variation is a response to ecological character displacement or local adaptation in the area of sympatry. I find evidence of pollinator preference for the ancestral allopatric flower color in allopatry, which may explain the persistence of the pattern of character displacement. These investigations of reproductive character displacement and reinforcement address important areas of research in evolutionary biology including the genetic basis of adaptation, the formation of species, and pleiotropy and conflicting selection pressures in species.</p> / Dissertation

<p>Diversity in coloration is a common phenomenon in marine invertebrates, although the ecological significance of the diversity is often unknown. Patterns of geographic variability, particularly with respect to color phenotypes, are evident in many organisms and may provide visual evidence of natural selection. </p><p>This dissertation examined the geographic and genetic variability of color patterns and morphology of the sea urchin <italic>Lytechinus variegatus </italic>. This study had 3 objectives: 1) to describe and quantify phenotypic diversity--color and morphology--throughout the geographic range; 2) to determine the heritability of color in genetic crosses between individuals with similar and differing phenotype; 3) to assess the degree of genetic divergence between and within the regions and congruence between the phylogenetic mitochondrial COI data and color phenotypes seen in the field.</p><p>The distribution of color phenotypes in the field is highly variable across the geographic range which stretches from Beaufort NC to southern Brazil and throughout the Gulf of Mexico and Caribbean. Urchins in each of the 5 regions sampled (Beaufort, Gulf, Keys, Panama and Brazil) have a distinct phenotypic composition despite the presence of similar color morphs. The two regions at the extremes--Beaufort and Brazil--demonstrate the most homogeneous phenotypes, each with a single dominant color morph. The Keys has the most heterogeneous composition with all 14 color morphs present. Morphological diversity mirrors color diversity in being highly variable across the range. Urchins in Beaufort are significantly different morphologically from urchins in the central portion of the range, with thicker, flatter tests and longer more robust spines.</p><p>The heritability of color phenotypes and morphology suggests that genes rather than environment have a major role in color phenotype and patterning as well as morphology in test, spines and lanterns. F₁ and F₂ offspring of Beaufort and Tavernier Key crosses resemble the parental phenotypes in both morphology and color phenotype. Hybrids from crosses between regions have a mixed color palette and intermediate morphological characteristics. The crosses establish that in <italic>L. variegatus </italic>the white phenotype is a dominant autosomal trait and green and purple are recessive and co-expressed. Patterning of the test and spines is dominant to non-patterning. </p><p>Analysis of the mitochondrial COI gene in urchins from Beaufort, Gulf and Keys regions revealed two clades. Clade 1 composed exclusively of Keys urchins differed significantly (F_ST = 0.89, <italic>P</italic> < 0.001) from Clade 2 composed of urchins from Beaufort, Gulf and Keys. Genetic differentiation within Clade 2 was zero, indicating that urchins in these regions are genetically identical. The genetic split between phenotypically indistinguishable Keys urchins suggests cryptic species. Genetic differentiation does not concord with phenotypic and morphological differentiation. No structure was detected with regards to color phenotype in either clade or region of origin in Clade 2.</p> / Dissertation

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