Arterial variants, defined as atypical presentations of anatomy including aberrant origin, course, and branching pattern, are important to be aware of because of their effects in the clinical setting as well as their possible link to pathology. Much research has already been done focusing on specific arterial variants in a specific region in the body. However, more research is needed to determine if there is a relationship between arterial variants in different regions of the body. The purpose of this study is to examine the whole-body arterial system of body donors in order to assess if there is a relationship between the presence of arterial variants in one region of the body to the other. The entire arterial system of twenty-five formalin fixed body donors was examined for the presence of arterial variants. The data was separated into two main categories, central variants (e.g. arch of the aorta, unpaired abdominal aortic branches) and peripheral variants (e.g. upper and lower extremities). The relationship between the central and peripheral variants was determined using quantitative observation, specifically, by examining the percent frequency of cases where arterial variants were co-occurring. Of the body donors examined, all were found to have at least one arterial variant, with an average of 8.7 variants per body. Arterial variants were most commonly found in the foregut with prevalence of 80%, the midgut (68%), left subclavian (60%), right upper extremity (52%), and the left upper extremity (48%). Of the central arterial variants, a percent frequency of 20% was found for the arch of the aorta, 20% for the coronary artery, 12% for the hindgut, 28% for the right renal, and 28% for the left renal. For the peripheral variants, the percent frequencies were as follows: brain variants were 4%, right carotid 8%, left carotid 0%, right subclavian 28%, left upper extremity 40%, right suprarenal 24%, left suprarenal 12%, right phrenic 24%, left phrenic 12%, gonadal 4%, right iliac 40%, left iliac 32%, and right lower extremity 40%. Examination of the relationship between central variants and peripheral variants reveals that the most common arterial variants to occur in tandem in the sample were those of the variant foregut with variants of the left subclavian artery (52% of cases), the upper and lower extremities (36-44% and 40-44% of cases, respectively), and the right iliac artery (36% of cases). The most common central arterial variants to co-occur were the variants of the foregut and midgut observed in 64% of cases. The frequency of cases involving normal central anatomy and variant peripheral anatomy indicates that vascular variants in the periphery are likely unrelated to variants in the central body cavities. However, it does seem like there are “hot spots” for arterial variants to occur, including the foregut, midgut left subclavian artery, right and left upper extremities, the right iliac artery, and the right and left lower extremities. Although there was no discernable pattern found between vascular variants in the present study, that does not preclude the possibility that there is a significant relationship between certain vascular variants. Either way, the high prevalence of cases with multiple arterial variations suggests that they may be more likely to occur than previously thought.

The differentiation of melanocytes from multipotential neural crest cells is an ideal system for studying the processes underlying lineage determination in development. Tyrosinase is a key enzyme in melanin biosynthesis and the activation of the tyrosinase gene is characteristic of differentiated melanocytes. In order to study the mechanisms underlying activation of melanocyte-specific genes during differentiation in chick embryos, a chicken genomic DNA library was screened for tyrosinase-encoding sequences using a mouse tyrosinase cDNA probe. Two identical hybridising clones were identified. Restriction mapping and sequencing revealed that both clones contained a 4.3 kb genomic DNA fragment, CTYR4.3, that included 2125 nt of the 5' flanking region, the first exon and part of the first intron of the chicken tyrosinase gene. The 5' flanking sequence of CTYR4.3, which is the most extensive to be reported for a lower vertebrate tyrosinase gene to date, was analysed further using computer-aided homology searches and primer extension. Alignment of the promoter sequences of CTYR4.3 with those of the human, mouse, quail and turtle tyrosinase genes revealed two evolutionary conserved regions. These regions may be functionally significant as they contain regulatory elements previously reported to play a role in melanocyte-specific expression of the tyrosinase gene in mammals. These include an initiator region and an associated SP1-binding site, the M-box and an upstream enhancer element, TDE. In addition, other potential transcription factor binding motifs were identified, including an AP-1-binding site, a UV-responsive element and glucocorticoid-responsive elements. Although several TATA box motifs were identified, they were situated more than 200 bp upstream of the transcription start sites mapped by primer extension analysis and therefore are unlikely to function as TFIID-binding sites. Transcription initiation appears to occur at heterogeneous start sites, and given the absence of a functional TATA box, may be mediated via the conserved initiator region and SP1-binding site. To test the ability of the 5' flanking sequence of CTYR4.3 to drive transcription and to begin to assess the functional significance of the various conserved elements, transient transfection assays were carried out. Constructs were generated in which 2.1 kb, 1.1 kb, 0.5 kb and 0.2 kb fragments of the 5' flanking sequence were linked to a luciferase reporter gene. These constructs were introduced into cultures of chicken retinal pigment epithelial cells (RPE), immortalised quail neural crest cells (MQTNC), and human liver cells (Hep G2) by calcium phosphate-mediated transfection. Transfections with all constructs resulted in luciferase activities significantly greater than those that were observed with the promoterless luciferase construct, thus confirming that the 5' flanking sequence of CTYR4.3 does possess promoter activity. However, the level of expression from the various constructs differed markedly in the different cell types. In the tyrosinase-negative Hep G2 cells, low levels of expression were observed with all constructs. In the tyrosinase-positive RPE cells, a high level of luciferase activity was obtained specifically with the smallest (0.2 kb) promoter construct. Since the 0.2 kb promoter fragment does not include the conserved initiator region, SP1-binding site, or M-box, the role of these elements in tissue-specific transcription initiation of the chicken tyrosinase gene is now questionable. These results suggest the existence of transcription regulatory mechanisms that are unique to avians and possibly other lower vertebrates. In contrast to the results obtained for RPE cells, the highest luciferase activity was obtained with the full length 2.1 kb promoter construct in the immortalised quail neural crest-derived cells. These results may have developmental significance since they suggest that the chicken tyrosinase gene promoter is regulated differently in RPE cells and neural crest-derived cells.

Diss. Linköping : Univ., 2005.

Os métodos de controle de qualidade tradicionais aplicados ao radiodiagnóstico, é a melhor maneira de garantir a boa qualidade das imagens produzidas. No entanto, a investigação de particularidades oriundas do processo de formação de imagens radiológicas requer ferramentas computacionais complementares, em função do número de variáveis envolvidas. Entretanto, os fantomas computacionais baseados em voxels não conseguem representar as variações morfométricas necessárias para a simulação de exames cujo diagnóstico é baseado em imagem. Neste trabalho foi desenvolvido um novo tipo de fantoma computacional, baseado em modelagem 3D, que possui as vantagens apresentadas pelos fantomas computacionais tradicionais sem os problemas encontados nestes. A ferramenta de modelagem utilizada, o Blender, é disponibilizada gratuitamente na internet. A técnica utilizada foi a box modeling, que consiste na deformação de uma primitiva básica, nesse caso um cubo, até que apresente a forma da estrutura que se deseja modelar. Para tanto, foram utilizadas como referencia, imagens obtidas de atlas de anatomia e fotografias de um esqueleto fornecido pela Universidade de Mogi das Cruzes. Foram modelados o sistema ósseo, os órgãos internos e a anatomia externa do corpo humano. A metodologia empregada permitiu a alteração de parâmetros do modelo dentro da ferramenta da modelagem. Essa possibilidade foi mostrada através da variação, dos formatos do intestino e do aumento da quantidade de tecido adiposo da malha referente a pele. A simulação das imagens radiológicas foi realizada a partir de coeficientes de atenuação de massa de materiais, ossos e tecidos e de modelos com diversas características físicas. Essa versatilidade permite prever a influência que as diferenças morfométricas entre os indivíduos provocam nas imagens, propriciando dessa forma, uma ferramenta relevante complementar aos métodos de controle de qualidade tradicionais. / The conventional methods of quality control applied to radio diagnosis are the best way to have assured good quality of the produced images. Due the amount of variables to consider, the study of particular issues of the process of formation of radiological images requires complementary computational tools. However, the computational voxel based phantoms are not suitable to represent the morphometrical variations, intended for test simulations with image based diagnosis. This work developed a new type of computational phantom, based on 3D modelling. It has the same advantages of the conventional ones, without some of their restrictions. The modeling tool employed, Blender, is available on internet for free download. The project uses the technique called box modeling, which consists in the deformation of a primitive form (a cube, in this case) until it presents a similar form to that it is wanted to model. In order to achieve it, some images, obtained from anatomy atlas and a skeleton pictures obtained from University of Mogi das Cruzes, were used as reference. Were built models from skeletal system, internal organs and external human body anatomy. The applied methodology allowed model´s parameter settings on the modelling tool. This option was presented by means of intestine format variation and increase of adipose tissue on the mesh that represents skin. The simulation of radiological images was done by means of x-ray mass attenuation coefficients, bones and tissues and models with diferent physical characteristics. This flexibility allows the analysis and forecasting of the influences that morphometrical differences of individual implies on images, revealing an important tool that complements the conventional quality control tools.

Birds are the most diverse extant group of terrestrial vertebrates, and relationships amongst major extant and extinct avian lineages remain hotly debated. A clade of Aves which has received limited attention is the extinct Zygodactylidae, a species-rich group of perching birds that possess a foot with a retroverted fourth toe, an elongate tarsometatarsus and a large intermetacarpal process in the wing. Specimens currently included within Zygodactylidae previously were thought to be sister taxa to songbirds (Passeriformes) or woodpeckers and allies (Piciformes). Zygodactylids were most abundant during the Eocene in North America and Europe and persisted to the Early Miocene. Five exceptionally preserved fossils from the Early Eocene Green River Formation of Wyoming are described, and provide insights into the interrelationships of zygodactylid taxa and the position of the clade within Aves. In an attempt to resolve systematic relationships within zygodactylids, and the position of the clade within Aves, I conducted two sets of phylogenetic analyses. The first focused on clarifying relationships within Zygodactylidae. Each taxon was evaluated for 37 morphological characters. Resulting strict consensus cladograms yield topologies in which two of the new Green River specimens are positioned in a clade within Zygodactylus, a taxon previously known only from the Early Oligocene and Early Miocene of Europe. The second set of analyses sought to assess which extant avian lineage is most closely allied with Zygodactylidae. Those analyses used a dataset of 135 characters evaluated for 57 species and a supraspecific terminal, Zygodactylidae. Scoring of Zygodactylidae was based on morphological observations from all described taxa within Zygodactylidae. The extant species sample was chosen to evaluate previously proposed hypotheses of relationships between Zygodactylidae and other avian clades and included songbirds, parrots and 43 species from the coraciiform-piciform clade (e.g., woodpeckers, galbulids, rollers and motmots). Outgroup species were iteratively swapped to determine if outgroup choice affected recovered estimates of zygodactylid relationships within Aves. Zygodactylidae is the sister taxon to songbirds in the resultant tree topologies. These results forward our understanding of the relationship between Zygodactylidae and Passeriformes within Aves. / text

In this work habitats impact to dandelion´s anatomic and morphologic state. Dandelion´s leaf is dorsoventral, bifaciral type. Mesophyll habitat epidermal cells are izodeometric, waved, whereas in the higrophyll – slightly waved and extended in tangential direction. Mesophyll habitat epidermal cells´ number is bigger than in the higrophyll. In the mesophyll habitat on the upper epidermal cells´ number is 85,4, on the lower – 87,2 per 1 mm², accordingly in the higrophyll habitat – 79,3 and 82,4 per 1 mm². Stomata apparatus per 1mm² are more in the higrophyll habitat (on the upper lamina´s side there were 20,2, on the lower – 24,9 stomata apparatus), than in the mesophyll (on the upper lamina´s side there were 14,8, on the lowe – 19,5 stomata apparatus). In the mesophyll habitat upper lamina´s side stomata´s coefficient was 19,36% and 45,57%. Dandelion´s leafstalk is ivugularly – shaped trapezium. In the mesophyll habitat – double, in the higrophyll – single, air spaces´ diameter – 1056 ��. In the lamina´s epidermis the stomata apparatus is not found neither on the upper, nor on the lower side. Dandelion´s leafstalk is represented by tabular collenchyma. In the leafstalk´s parenchyma articulate communicating latex vessel are situated. Investigated on the Taraxacum officinale, wich is growing in the mesophyll and higrophyll habitats, anatomic state of radix is definited that changing habitat the anatomic state of radix shifts a little bit. Independent of habitat radix is... [to full text]

Magistro darbe pateikti paprastojo raudonėlio (Origanum vulgare L.) rausvažiedės ir baltažiedės formų, augančių VDU Kauno botanikos sodo vaistinių ir prieskoninių augalų kolekcijoje, vegetatyvinių organų lapo ir stiebo anatominės ir morfologinės sandaros ypatumai, bei įvertinti generatyvinių ir vegetatyvinių organų morfologinių požymių parametrų skirtumai. Nustatyti koreliacijos koeficientai tarp stiebo aukščio ir žiedyno ilgio, priklausomybė mentūrių skaičiaus žiedyne nuo žiedyno ilgio ir lapalakščio plošio ir ilgio tarpusavio priklausomubė. Visur pasireiškė teigiami koreliacijos ryšiai, kai vienam rodikliui didėjant, didėja ir kitas rodiklis. Abiejų tirtų paprastojo raudonėlio (Origanum vulgare L.) formų stiebas daugiametis, medėjantis, ne kulelinio tipo. Apytakos audiniai išsidėsto sifonostelėje. Vandens indai pavieniai. Būdingi spiraliniai ir tinkliniai vandens indai. Spiraliniai vandens indai su snapeliu. Žiotelinis aparatas anizocitinio ir diacitinio tipo, išsidėsto adoksalinėje ir aboksalinėje lapo pusėse. Origanum vulgare L. raudonžiedžio viršutinėje lapo pusėje 1mm² vidutiniškai 40, o apatinėje 125 žiotelių. Origanum vulgare L. baltažiedžio lapo viršutinėje pusėje vidutiniškai 1mm² 35, o apatinėje 97 žiotelių. Raudonėlio (Origanum L.) genties augaluose yra šizogeninės kilmės liaukos. Origanum vulgare L. raudonžiedžio sėklų daigumas buvo tiriamas mirkant ir daiginant jas katolitiniame ir anolitiniame vandenyje. Nustatyta, kad katolitinis vanduo skatina paprastojo... [toliau žr. visą tekstą] / This MA thesis paper presents an overview of the specific characteristics of the anatomic and morphologic formation of the vegetative organs – the leaf and the stem – of the red and white blossom varieties of simple oregano (Origanum vulgare L.) that are cultivated as part of the medicinal plants and potherbs collection at the Kaunas botanical garden of the Vytautas Magnus University. The work also presents an evaluation of differences between the parameters of morphologic characteristics of generative and vegetative organs. Determined are the correlation ratios for the height of the stem and the length of the inflorescence, the relationship between the number of whorls in the inflorescence and the length of the latter, as well as the interrelation of the lenth and the width of the lamina. Positive correlation (when an increase in one variable resulted in the increase of another variable) was determined in all cases. The stem of both studied forms of simple oregano (Origanum vulgare L.) is perennial, lignificating, of a non-bundle type. Circulation tissues are arranged in a siphonostele. Water vessels are single. Spiral and cellular water vessels are common. The spiral ones feature a nozzle. The leaves of the plants belonging to the oregano genus (Origanum L.) are equifacial. The length of the static tissue’s cells varies from 83 µm to 87 µm, while the width varies from 33 µm to 44 µm. The stomatic apparatus is of the anisocitic and diacitic types, located on the adoxal... [to full text]

Thesis (M.A.) -- University of Texas Southwestern Medical Center at Dallas, 2004. / Vita. Bibliography: [91-92].

abstract: Detecting anatomical structures, such as the carina, the pulmonary trunk and the aortic arch, is an important step in designing a CAD system of detection Pulmonary Embolism. The presented CAD system gets rid of the high-level prior defined knowledge to become a system which can easily extend to detect other anatomic structures. The system is based on a machine learning algorithm --- AdaBoost and a general feature --- Haar. This study emphasizes on off-line and on-line AdaBoost learning. And in on-line AdaBoost, the thesis further deals with extremely imbalanced condition. The thesis first reviews several knowledge-based detection methods, which are relied on human being's understanding of the relationship between anatomic structures. Then the thesis introduces a classic off-line AdaBoost learning. The thesis applies different cascading scheme, namely multi-exit cascading scheme. The comparison between the two methods will be provided and discussed. Both of the off-line AdaBoost methods have problems in memory usage and time consuming. Off-line AdaBoost methods need to store all the training samples and the dataset need to be set before training. The dataset cannot be enlarged dynamically. Different training dataset requires retraining the whole process. The retraining is very time consuming and even not realistic. To deal with the shortcomings of off-line learning, the study exploited on-line AdaBoost learning approach. The thesis proposed a novel pool based on-line method with Kalman filters and histogram to better represent the distribution of the samples' weight. Analysis of the performance, the stability and the computational complexity will be provided in the thesis. Furthermore, the original on-line AdaBoost performs badly in imbalanced conditions, which occur frequently in medical image processing. In image dataset, positive samples are limited and negative samples are countless. A novel Self-Adaptive Asymmetric On-line Boosting method is presented. The method utilized a new asymmetric loss criterion with self-adaptability according to the ratio of exposed positive and negative samples and it has an advanced rule to update sample's importance weight taking account of both classification result and sample's label. Compared to traditional on-line AdaBoost Learning method, the new method can achieve far more accuracy in imbalanced conditions. / Dissertation/Thesis / M.S. Computing Studies 2011

Os métodos de controle de qualidade tradicionais aplicados ao radiodiagnóstico, é a melhor maneira de garantir a boa qualidade das imagens produzidas. No entanto, a investigação de particularidades oriundas do processo de formação de imagens radiológicas requer ferramentas computacionais complementares, em função do número de variáveis envolvidas. Entretanto, os fantomas computacionais baseados em voxels não conseguem representar as variações morfométricas necessárias para a simulação de exames cujo diagnóstico é baseado em imagem. Neste trabalho foi desenvolvido um novo tipo de fantoma computacional, baseado em modelagem 3D, que possui as vantagens apresentadas pelos fantomas computacionais tradicionais sem os problemas encontados nestes. A ferramenta de modelagem utilizada, o Blender, é disponibilizada gratuitamente na internet. A técnica utilizada foi a box modeling, que consiste na deformação de uma primitiva básica, nesse caso um cubo, até que apresente a forma da estrutura que se deseja modelar. Para tanto, foram utilizadas como referencia, imagens obtidas de atlas de anatomia e fotografias de um esqueleto fornecido pela Universidade de Mogi das Cruzes. Foram modelados o sistema ósseo, os órgãos internos e a anatomia externa do corpo humano. A metodologia empregada permitiu a alteração de parâmetros do modelo dentro da ferramenta da modelagem. Essa possibilidade foi mostrada através da variação, dos formatos do intestino e do aumento da quantidade de tecido adiposo da malha referente a pele. A simulação das imagens radiológicas foi realizada a partir de coeficientes de atenuação de massa de materiais, ossos e tecidos e de modelos com diversas características físicas. Essa versatilidade permite prever a influência que as diferenças morfométricas entre os indivíduos provocam nas imagens, propriciando dessa forma, uma ferramenta relevante complementar aos métodos de controle de qualidade tradicionais. / The conventional methods of quality control applied to radio diagnosis are the best way to have assured good quality of the produced images. Due the amount of variables to consider, the study of particular issues of the process of formation of radiological images requires complementary computational tools. However, the computational voxel based phantoms are not suitable to represent the morphometrical variations, intended for test simulations with image based diagnosis. This work developed a new type of computational phantom, based on 3D modelling. It has the same advantages of the conventional ones, without some of their restrictions. The modeling tool employed, Blender, is available on internet for free download. The project uses the technique called box modeling, which consists in the deformation of a primitive form (a cube, in this case) until it presents a similar form to that it is wanted to model. In order to achieve it, some images, obtained from anatomy atlas and a skeleton pictures obtained from University of Mogi das Cruzes, were used as reference. Were built models from skeletal system, internal organs and external human body anatomy. The applied methodology allowed model´s parameter settings on the modelling tool. This option was presented by means of intestine format variation and increase of adipose tissue on the mesh that represents skin. The simulation of radiological images was done by means of x-ray mass attenuation coefficients, bones and tissues and models with diferent physical characteristics. This flexibility allows the analysis and forecasting of the influences that morphometrical differences of individual implies on images, revealing an important tool that complements the conventional quality control tools.