Brain and central nervous cancer presents a significant clinical burden, accounting for 2.4% of all cancer deaths. High grade glioma is particularly deadly, with 5 year survival times of 35% or less. Traditional treatment includes tumor resection followed by radiation therapy or chemotherapy. Aggressive resection is essential in order to prolong patient life. In fact, several studies have shown that life expectancy increases with increased extent of resection. Extent of resection is burdened by the fact that surgeons must be careful not to remove functional brain tissue. Resection is incomplete more often than not due to lack of visual cues for the surgeon. He must rely on tactile sensation to distinguish tumor from healthy tissue. Methods such as intraoperative MRI and CT exist, but these require expensive equipment and special training that is not available in all surgical environments. Some laboratories have proposed small molecule dyes to solve this problem, but these are insufficient when used in an invasive tumor model. It was the goal of this research to provide an objective cue in the form of a nanoencapsulated visible dye without the need for additional equipment of changes to the surgery process itself other than injection of the dye. We hypothesized that the nanocarrier would allow staining of the tumor through passive targeting by taking advantage of the enhanced permeability and retention effect. Once the nanocarriers have reached the desired target, they would not diffuse out into healthy tissue due to their large size compared to small molecule dyes, which readily diffuse out and stain healthy tissue. To test this hypothesis, we prepared and characterized a liposomal nanocarrier encapsulating Evans blue dye. The nanocarrier was tested for safety in vitro and in vivo, then used to delineate tumor margins in an invasive rat glioma model in vivo. Microscopic analysis was then conducted to ensure only tumor tissue was stained by the nanocarrier. This thesis presents a successful method of tumor border delineation to provide surgeons with positive visual cues without the need for changes in surgical environment or techniques.

Orientador: Roberto Calderon Gonçalves / Banca: Alice Maria Melville Paiva / Banca: Simone Biagio Chiacchio / Resumo: Os estudos das secreções traqueobrônquicas são amplamente utilizados nas pesquisas de condições patológicas pulmonares nas diversas espécies animais, inclusive no homem. Os objetivos desta pesquisa foram a viabilização da técnica de colheita de lavado traqueobrônquico na espécie ovina e o estudo da relação clínico-citológica do lavado de ovinos portadores de afecções respiratórias e clinicamente sadios. Foram utilizados neste estudo 19 ovinos sem sintomatologia respiratória e 23 portadores de enfermidade respiratória com sinais clínicos e envolvimento de vias aéreas, divididos nos respectivos grupos. Após o exame físico foi realizado o lavado traqueobrônquico por via nasotraqueal. A colheita do lavado foi feita com a inoculação e aspiração de solução fisiológica estéril. As amostras foram processadas citologicamente através de citocentrifugação e coradas pelos métodos Giemsa, Shorr e Gram. Nos animais sadios notou-se predomínio de macrófagos, seguido por células epiteliais cilíndricas, neutrófilos e linfócitos. No grupo de animais doentes notou-se redução no número de macrófagos e aumento da freqüência cardíaca. Embora não tenha ocorrido diferença estatística significativa entre os grupos avaliados, notou-se tendência ao aumento de neutrófilos nos animais doentes. A técnica estudada mostrou-se eficaz na obtenção de fluidos traqueobrônquicos, por ser de fácil realização por médicos veterinários no campo, pouco dispendiosa, e obter material representativo da região traqueobrônquica. / Abstract: The studies of the tracheobrochial secretions are very useful in the research of the lung pathological conditions in different animal's species and in humans. The purposes of this research are to enable the collection technique of the tracheobronchial lavage in ovine and the study of the clinical cytology relationship of the lavage in ovines with respiratory disease and clinically healthy. In this study there were used 19 ovines without respiratory symptoms and 23 with respiratory disease with symptoms and airway involvement, separated in respective groups. After physical examination the tracheobronchial lavage was performed by nasotracheal via. The tracheobronchial lavage was performed by injection and aspiration of sterile saline. Cytology of the samples was proceeding by centrifugation and collored by Giemsa, Shorr and Gram methods. In the healthy animals was noted prevalence of macrophages, followed by cylindric epithelial cells, neutrophils and lymphocytes. In the ill animals group there was reduction in the macrophages and higher heart rate. Despite there was no considerable statistic difference between the analyzed groups, a tendency in the increase of the neutrophils number in the ill group was noted. The evaluated technical showed itself to be efficient to obtain tracheobronchial fluid, considering its easy proceeding by veterinarians in the field, no expensive and obtaining representative volume of the samples from the tracheobronchial region. / Mestre

Made available in DSpace on 2014-06-11T19:23:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-01Bitstream added on 2014-06-13T20:11:21Z : No. of bitstreams: 1 legatti_e_me_botfmvz.pdf: 505379 bytes, checksum: d0ebc26e693dd968ef47d606c20308a7 (MD5) / A Cromoendoscopia é definida como a aplicação tópica de corantes aquosos na mucosa do trato gastrointestinal. Estes corantes evidenciam alterações precoces ou discretas que passariam despercebidas ao exame convencional, permitindo assim a coleta de tecido alterado ou o acompanhamento de doenças pré existentes. Na Medicina Veterinária, não foram encontrados trabalhos que tenham utilizado esta técnica, mas há muitas situações em que ela pode ser empregada como a pesquisa ou o acompanhamento de: esofagites (como esôfago de Barrett em humanos), lesões gástricas erosivas ou polipóides e lesões duodenais. Utilizando os corantes escolhidos, este trabalho teve como objetivos: demonstrar a aplicação da cromoendoscopia em cães e confirmar sua eficácia quanto à identificação e delimitação de lesões no trato digestório superior destes animais; descrever vantagens e desvantagens da cromoendoscopia no direcionamento e aquisição de amostras de biópsia do trato digestório superior de cães; e correlacionar os achados endoscópicos pré e pós aplicação da técnica com os resultados histopatológicos. O estudo utilizou 10 cães adultos provenientes do Canil Municipal de Botucatu, do Canil da UNESP FMVZ Botucatu e da rotina do Hospital Veterinário da UNESP FMVZ Botucatu. Todos os animais realizaram endoscopia digestiva alta (EDA) seguida de Cromoendoscopia (CRE) e coleta de biópsia da mucosa esofágica, gástrica e duodenal, quando acessível. As biópsias foram enviadas para exame histopatológico e identificação de presença ou ausência de lesão no material coletado. Os resultados demonstraram concordância importante na cromoendoscopia (CRE) de esôfago com acurácia de 83,33%. Concordância moderada na endoscopia convencional (E.C.) de esôfago e na CRE de fundo, corpo e antro piloro com acurácia de... / Chromoendoscopy is defined as the topical application of aqueous dye mucosa of the gastrointestinal tract. These dyes show early changes or mild they go unnoticed to the conventional examination, allowing the collection of tissue changes or monitoring pre-existing diseases. In Veterinary Medicine, there were no studies that have used this technique , but there are many situations in which it can be employed as research or monitoring esophagitis (such as humans Barrett's esophagus), erosive or polypoid gastric lesions and duodenal injuries . Using the colors chosen, this work was objectives: to demonstrate the technique of chromoendoscopy in dogs and evaluate its effectiveness as the identification and delineation of chronic or early lesions, often unapparent, in the upper digestive tract these animals; describe advantages and disadvantages of chromoendoscopy in targeting and acquisition of biopsy specimens of the upper digestive tract of dogs, and correlate the endoscopic findings before and after technique application with the histopathologic results. The study used 10 adult dogs from the Botucatu Municipal Kennel, UNESP kennel FMVZ Botucatu and routine FMVZ Veterinary Hospital of UNESP Botucatu. Every animals performed upper endoscopy (EGD) followed by Chromoendoscopy (CRE) and collecting biopsy of the esophageal mucosa, gastric and duodenal when available. Biopsies were sent for examination and identification of pathological presence or absence of lesions in the material collected. The results showed chromoendoscopy (CRE) important concordance of the esophagus with an accuracy of 83.33%. Moderate concordance in conventional endoscopy (CE) of the esophagus and CRE fundus, body and pyloric antrum with an accuracy of 83.33%, 70%, 70% e 70% respectively. Reasonable concordance in CRE... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:23:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-22Bitstream added on 2014-06-13T19:30:12Z : No. of bitstreams: 1 marcondes_js_me_botfmvz.pdf: 567670 bytes, checksum: 1ff58f582a8a4a863c4ee08a32172d9a (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os estudos das secreções traqueobrônquicas são amplamente utilizados nas pesquisas de condições patológicas pulmonares nas diversas espécies animais, inclusive no homem. Os objetivos desta pesquisa foram a viabilização da técnica de colheita de lavado traqueobrônquico na espécie ovina e o estudo da relação clínico-citológica do lavado de ovinos portadores de afecções respiratórias e clinicamente sadios. Foram utilizados neste estudo 19 ovinos sem sintomatologia respiratória e 23 portadores de enfermidade respiratória com sinais clínicos e envolvimento de vias aéreas, divididos nos respectivos grupos. Após o exame físico foi realizado o lavado traqueobrônquico por via nasotraqueal. A colheita do lavado foi feita com a inoculação e aspiração de solução fisiológica estéril. As amostras foram processadas citologicamente através de citocentrifugação e coradas pelos métodos Giemsa, Shorr e Gram. Nos animais sadios notou-se predomínio de macrófagos, seguido por células epiteliais cilíndricas, neutrófilos e linfócitos. No grupo de animais doentes notou-se redução no número de macrófagos e aumento da freqüência cardíaca. Embora não tenha ocorrido diferença estatística significativa entre os grupos avaliados, notou-se tendência ao aumento de neutrófilos nos animais doentes. A técnica estudada mostrou-se eficaz na obtenção de fluidos traqueobrônquicos, por ser de fácil realização por médicos veterinários no campo, pouco dispendiosa, e obter material representativo da região traqueobrônquica. / The studies of the tracheobrochial secretions are very useful in the research of the lung pathological conditions in different animal's species and in humans. The purposes of this research are to enable the collection technique of the tracheobronchial lavage in ovine and the study of the clinical cytology relationship of the lavage in ovines with respiratory disease and clinically healthy. In this study there were used 19 ovines without respiratory symptoms and 23 with respiratory disease with symptoms and airway involvement, separated in respective groups. After physical examination the tracheobronchial lavage was performed by nasotracheal via. The tracheobronchial lavage was performed by injection and aspiration of sterile saline. Cytology of the samples was proceeding by centrifugation and collored by Giemsa, Shorr and Gram methods. In the healthy animals was noted prevalence of macrophages, followed by cylindric epithelial cells, neutrophils and lymphocytes. In the ill animals group there was reduction in the macrophages and higher heart rate. Despite there was no considerable statistic difference between the analyzed groups, a tendency in the increase of the neutrophils number in the ill group was noted. The evaluated technical showed itself to be efficient to obtain tracheobronchial fluid, considering its easy proceeding by veterinarians in the field, no expensive and obtaining representative volume of the samples from the tracheobronchial region.

Orientador: Luiz Carlos Vulcano / Coorientador: Luiz Eduardo Naresse / Banca: Marcos Jun Watanabe / Banca: Érika Veruska Paiva Ortolan / Resumo: A Cromoendoscopia é definida como a aplicação tópica de corantes aquosos na mucosa do trato gastrointestinal. Estes corantes evidenciam alterações precoces ou discretas que passariam despercebidas ao exame convencional, permitindo assim a coleta de tecido alterado ou o acompanhamento de doenças pré existentes. Na Medicina Veterinária, não foram encontrados trabalhos que tenham utilizado esta técnica, mas há muitas situações em que ela pode ser empregada como a pesquisa ou o acompanhamento de: esofagites (como esôfago de Barrett em humanos), lesões gástricas erosivas ou polipóides e lesões duodenais. Utilizando os corantes escolhidos, este trabalho teve como objetivos: demonstrar a aplicação da cromoendoscopia em cães e confirmar sua eficácia quanto à identificação e delimitação de lesões no trato digestório superior destes animais; descrever vantagens e desvantagens da cromoendoscopia no direcionamento e aquisição de amostras de biópsia do trato digestório superior de cães; e correlacionar os achados endoscópicos pré e pós aplicação da técnica com os resultados histopatológicos. O estudo utilizou 10 cães adultos provenientes do Canil Municipal de Botucatu, do Canil da UNESP FMVZ Botucatu e da rotina do Hospital Veterinário da UNESP FMVZ Botucatu. Todos os animais realizaram endoscopia digestiva alta (EDA) seguida de Cromoendoscopia (CRE) e coleta de biópsia da mucosa esofágica, gástrica e duodenal, quando acessível. As biópsias foram enviadas para exame histopatológico e identificação de presença ou ausência de lesão no material coletado. Os resultados demonstraram concordância importante na cromoendoscopia (CRE) de esôfago com acurácia de 83,33%. Concordância moderada na endoscopia convencional (E.C.) de esôfago e na CRE de fundo, corpo e antro piloro com acurácia de... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract:Chromoendoscopy is defined as the topical application of aqueous dye mucosa of the gastrointestinal tract. These dyes show early changes or mild they go unnoticed to the conventional examination, allowing the collection of tissue changes or monitoring pre-existing diseases. In Veterinary Medicine, there were no studies that have used this technique , but there are many situations in which it can be employed as research or monitoring esophagitis (such as humans Barrett's esophagus), erosive or polypoid gastric lesions and duodenal injuries . Using the colors chosen, this work was objectives: to demonstrate the technique of chromoendoscopy in dogs and evaluate its effectiveness as the identification and delineation of chronic or early lesions, often unapparent, in the upper digestive tract these animals; describe advantages and disadvantages of chromoendoscopy in targeting and acquisition of biopsy specimens of the upper digestive tract of dogs, and correlate the endoscopic findings before and after technique application with the histopathologic results. The study used 10 adult dogs from the Botucatu Municipal Kennel, UNESP kennel FMVZ Botucatu and routine FMVZ Veterinary Hospital of UNESP Botucatu. Every animals performed upper endoscopy (EGD) followed by Chromoendoscopy (CRE) and collecting biopsy of the esophageal mucosa, gastric and duodenal when available. Biopsies were sent for examination and identification of pathological presence or absence of lesions in the material collected. The results showed chromoendoscopy (CRE) important concordance of the esophagus with an accuracy of 83.33%. Moderate concordance in conventional endoscopy (CE) of the esophagus and CRE fundus, body and pyloric antrum with an accuracy of 83.33%, 70%, 70% e 70% respectively. Reasonable concordance in CRE... (Complete abstract click electronic access below) / Mestre

Quand une source de lumière cohérente éclaire un milieu présentant soit une rugosité de surface à l’échelle de la longueur d’onde de la lumière incidente, soit des variations d’indice de réfraction, les ondes diffusées se propagent suivant différents chemins optiques. Les ondelettes ainsi créées, toujours cohérentes, interfèrent entre elles dans un plan d’observation, créant un champ de speckle. Dans ce travail, nous couplons l’analyse du champ de speckle à l’analyse de la polarisation de la lumière en adoptant une approche multiparamètre regroupant des informations spatiales et temporelles. La capacité du speckle polarisé à caractériser des propriétés de milieux diffusants complexes est exploitée. Des informations liées à un changement de proportions de tailles de diffuseurs, de coefficient d’absorption, et de dynamique intrinsèque des diffuseurs sont extraites. Les méthodologies développées sont appliquées à la caractérisation d’échantillons biologiques, à la détection de phases préliminaires d’érosion dentaire, et au suivi de réactions de polymérisation. / When a coherent light source illuminates a random medium, having either surface roughness or refractive index variations, the scattered waves propagate following different optical paths. The coherent created wavelets interfere with each other in a certain observation plane, creating the speckle field. In this work, we simultaneously the analysis of the speckle field as well as the analysis of polarized light, in a multi-parameter approach combining spatial and temporal information. The capability of the polarized speckle field to characterize complex scattering media is investigated. Information related to changes in diffusers sizes and proportions, absorption coefficient, and intrinsic dynamics are extracted. The developed methodologies are applied to characterize biological samples, to diagnose early stages of dental erosion, and to monitor polymerization reactions.

Thesis (MMed)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Background Occult blood loss from the gastrointestinal tract (GIT), causing iron deficiency often with anaemia, can be diagnostically and therapeutically challenging. This is because the endoscopic and radiologic tests may be negative due to the slow, chronic and intermittent nature of the gastrointestinal bleeding, making timing key in detection and localisation of the bleed. These limitations can be approached using two different radioactive isotopes. Firstly, we tested the sensitivity of extending Cr-51 RBC for 21 days relative to 5 days to detect GIT bleeding and its use to optimise timing of a Tc-99m RBC study for GIT blood loss localisation. Finally, we tested if the information provided by the Tc-99m RBC study aided gastroenterologic intervention for anatomical localisation of a lesion. Method In this retrospective review, after obtaining institutional and ethics committee approval, records of patients referred for evaluation of possible GIT blood loss were reviewed. In each; daily appearance of radiochromium in stool was measured in the whole body counter. In those cases exceeding 50 ml/day, a technetium-99m (Tc-99m) localization study was performed. These studies were correlated with clinical findings. Results A total of 59 Cr-51 RBC studies were carried out in 36 females and 21 males (n = 57). In 32 (54%) the radiochromium results were positive with 75% of the bleeding incidences occurring after 5 days of stool collection. Of 17 cases in whom Tc-99m RBC imaging studies were performed, 14 (82%) were positive with specific anatomical sites successfully defined in twelve. In all patients with blood loss of >100 ml/24h, Tc-99m RBC were positive and localised. Ten of the 17 Tc-99m RBC studies were further investigated and half diagnosed with small-bowel angiodysplasia. Conclusion This sequential twin isotope method is practical in revealing otherwise silent intestinal haemorrhage. Although it has good patient acceptability and clinical as well as diagnostic utility in management, further studies are required to clearly establish a cut-off level of blood loss for performing imaging studies and the impact of the findings on the overall patient management. / AFRIKAANSE OPSOMMING: Agtergrond Die evaluasie van okkulte bloedverlies uit die gastro-intestinale kanaal (GIT), met gevolglike ystertekort anemie, kan diagnosties en terapeuties uitdagend wees. Dit is omdat endoskopiese en radiologiese ondersoeke negatief mag wees as gevolg van die stadige, chroniese en intermitterende aard van die gastro-intestinale bloeding, wat die presiese tydstip van opsporing en lokalisering van die bloeding krities belangrik maak. Hierdie beperkings kan aangespreek word deur twee verskillende radioaktiewe isotope te gebruik. Eerstens is die sensitiwiteit van die verlenging van die Cr-51 RBS studie tot 21 dae in plaas van 5 dae om die GIT bloeding op te spoor, getoets, asook die gebruik daarvan om die optimale tyd vir ‘n Tc-99m RBS studie om die GIT bloedverlies te lokaliseer, vas te stel. Laastens is getoets of die inligting van die Tc-99m RBS studie wel bygedra het tot die gastroenterologiese ingreep om die letsel anatomies te lokaliseer. Metode Na institusionele en etiese komitee toestemming is inligting van pasiënte wat vir die evaluering van ‘n moontlike GI bloedverlies verwys is, in hierdie retrospektiewe oorsig nagegaan. Die daaglikse voorkoms van radioaktiewe chroom in stoelgangmonsters is in ‘n heelliggaamteller gemeet. In gevalle waar dit 50 ml/dag oorskry het, is ‘n tegnesium 99m (Tc 99m) studie gedoen. Hierdie studies is met die kliniese bevindinge gekorreleer. Resultate ‘n Totaal van 59 Cr-51 RBS studies is in 36 vroue en 21 mans (n = 57) gedoen. Die gemerkte chroomstudies was positief in 32 (54%), met 75% van die bloedings wat meer as 5 dae na versameling van die stoelgang plaasgevind het. In veertien (82%) van die 17 gevalle waar Tc-99m RBS studies gedoen is, was die studies positief. Spesifieke anatomiese gebiede van bloeding kon in 12 hiervan suksesvol bevestig word. Tc-99m RBS studies was positief in al die pasiënte met ‘n bloedverlies van >100 ml/24h, en kon gelokaliseer word. Tien van die 17 Tc-99m RBS studies is verder ondersoek en die helfte daarvan gediagnoseer met dunderm angiodisplasie. Gevolgtrekking Die opeenvolgende twee isotoopmetode om andersins asimptomatiese dermbloeding op te spoor, is prakties uitvoerbaar. Alhoewel die studies goed deur pasiënte aanvaar is, en ook van kliniese en diagnostiese waarde in die hantering van die pasiënte is, is verdere studies nodig om die afsnypunt vir die hoeveelheid bloedverlies om beeldingstudies uit te voer, sonder twyfel vas te stel, asook om die impak van die bevindings op ‘n groter pasiëntpopulasie vas te stel.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / O auxÃlio ao diagnÃstico atravÃs da visualizaÃÃo de imagens mÃdicas vÃm sendo utilizado em diversas Ãreas da Medicina tais como pneumologia, cardiologia, traumatologia, neurologia, dentre outras. Na Ãrea da cardiologia, vÃrias aplicaÃÃes clÃnicas tÃm sido propostas para a anÃlise de doenÃas cardÃacas atravÃs da quantificaÃÃo e avaliaÃÃo da dessincronia ventricular esquerda durante a deformaÃÃo do mÃsculo cardÃaco (miocÃrdio). Existem, atualmente, duas tÃcnicas utilizadas na aferiÃÃo da deformaÃÃo miocÃrdica em duas dimensÃes: Doppler Tecidual (DT) e Strain 2D (St2D). A primeira tÃcnica possui desvantagens quanto à dependÃncia do Ãngulo de insonaÃÃo do transdutor durante o exame ecocardiogrÃfico, diminuindo a chance de reprodutibilidade do resultado das mediÃÃes entre especialistas. A segunda tÃcnica, recentemente introduzida e tambÃm chamada de Speckle Tracking, consiste no acompanhamento de marcadores acÃsticos naturais existentes na imagem produzida pelo ultrassom. Neste sentido, vÃ-se a importÃncia do estudo de tÃcnicas para rastrear esses marcadores acÃsticos. A presente dissertaÃÃo realiza uma anÃlise comparativa entre oito algoritmos de estimaÃÃo de deslocamento baseados na tÃcnica de Casamento de Blocos (CB) e trÃs algoritmos baseados na tÃcnica de Fluxo Ãptico (FO), que sÃo as duas atuais tÃcnicas amplamente citadas na literatura. A anÃlise à realizada mediante vÃdeos sintÃticos e vÃdeos mÃdicos de exames ecocardiogrÃficos. A avaliaÃÃo das tÃcnicas em vÃdeos sintÃticos à realizada quanto à trajetÃria e à deformaÃÃo. Jà a avaliaÃÃo em vÃdeos de exames ecocardiogrÃficos à realizada quanto Ãs curvas e taxas de deformaÃÃo. Na anÃlise da trajetÃria sÃo aplicadas duas mÃtricas de avaliaÃÃo das tÃcnicas: correlaÃÃo mÃdia e erro quadrÃtico mÃdio. Para a anÃlise das curvas e das taxas de deformaÃÃo a mÃtrica usada à o valor do erro quadrÃtico mÃdio em relaÃÃo à deformaÃÃo global (global strain) do miocÃrdio. Os resultados indicam que o desempenho idÃntico de alguns estimadores de deslocamento os reduzem de oito para seis algoritmos. A tÃcnica de CB mostra-se viÃvel para o rastreamento de marcas acÃsticas mas à dependente das dimensÃes adotadas nos blocos. Em relaÃÃo Ãs tÃcnicas de FO, o algoritmo de Lucas e Kanade Piramidal à o que obtÃm melhor resultado nos testes realizados, produzindo curvas de deformaÃÃo global com erro mÃdio de 0,47%, enquanto os valores de erro dos outros algoritmos de FO estÃo em torno de 10%. No caso, os erros dos estimadores de CB variam de 1% a 16%. / Aided diagnosis by visualization of medical images has been used in several medical fields such as pulmonology, cardiology, traumatology, neurology, and others. In cardiology, several clinical applications have been proposed for the analysis of heart disease by quantification and evaluation of ventricular dyssynchrony during deformation of the heart muscle (myocardium). There are currently two techniques used in the measurement of myocardial deformation in two dimensions: Tissue Doppler and 2D Strain. The first technique has drawbacks regarding the dependence on the angle of insonation of the transducer during the echocardiographic examination, which reduce the chance of reproducibility of measurements among experts. The second technique, recently introduced and also called Speckle Tracking, consists of tracking the natural acoustic markers in the image produced by ultrasound. In this sense we see the importance of studying techniques to track these acoustic markers. This thesis performs a comparative analysis of eight algorithms from time-delay estimators based on the block matching technique and three algorithms based on the optical flow technique, which are the two current techniques widely presented in the literature. The analysis is performed using synthetic videos and medical videos from echocardiographic examinations. The evaluation of the techniques in synthetic videos is performed on the trajectory and deformation. The assessment in echocardiographic videos is held regarding the strain curves and strain rates. In the analysis of the trajectory are applied two metrics for evaluating techniques: mean correlation and mean square error. For the analysis of strain curves and of strain rate the measure used is the value of the mean square error relative to global strain of myocardium. The results indicate that the identical performance of some estimators reduce the time-delay estimators from eight to six algorithms. The block matching technique appears to be a viable technique for tracking acoustic marks but is dependent on the dimensions adopted in the blocks. Regarding optical flow techniques, the Lucas and Kanade Pyramidal algorithm is the one which gets the best results in the tests performed herein and produce global strain curves average error of 0.47 %, while the error values of the other optical flow algorithms are around 10 %. In case, the block matching time-delay estimators errors vary from 1% to 16%.

Nanoparticles are used in various applications like medical diagnostics, drug delivery, energy technology, electronics, catalysis etc. Although particles of such small dimensions can be synthesized through various methods, the liquid phase synthesis methods stands out for their simplicity. Typically, these methods involve reaction of precursors to form solute. At high concentration of solute, nucleation commences and nuclei are formed. These nuclei grow in size by assimilating solute from the bulk. Stabilizers or capping agents compete with solute for adsorption on the surface of a growing particle. Two partially protected particles can form bigger particle by coagulation. Uncontrolled turbulent flow field in laboratory scale reactors combined with all the above quite fast and poorly understood steps often lead to poorly controlled synthesis of particles. In many a systems, it also leads to very poor reproducibility. Any attempt to synthesis nanoparticles at engineering scale, with good control on mean size and polydispersity, requires quantitative understanding of the synthesis process. It can then be combined with description of other transport processes in reactors to optimize synthesis protocols. Two main factors hinder progress in this direction: complex and often poorly understood chemistry, and inefficient tools to simulate particle synthesis. In the first part of the thesis, a quantitative model is developed for tannic acid method of synthesis of gold nanoparticles. It showcases the approach used to model a system with poorly understood chemistry and which defies an understanding through the widely used homogeneous nucleation based mechanism for particle synthesis. An organizer based mechanism in which tannic acid brings together nucleating species to facilitate nucleation is invoked. Simple reaction network based models however fail to explain the experimental findings. The underlying chemistry is explored to develop a comprehensive reaction network. This network is used as a guide to seek pathways which can mimic burst of nucleation, a characteristic of homogeneous nucleation based mechanism, through self-limiting nucleation, and various other features present in the experimental data. After successful prediction of all the features of the experimental data through this network, a minimal organizer based mechanism which leads to self-limiting nucleation is developed. The minimal organizer model offers itself as a competing and alternative mechanism to explain nanoparticle synthesis. A few new predictions made by the new model are verified by others in our group. Monte-Carlo (MC) simulations are used as a powerful tool to simulate stochastic processes. Their application to nanoparticle synthesis is limited by three problems: (i) zero initial rate of stochastic processes which leads to infinite time step at the beginning of the simulation, (ii) sensitively time dependent rate of stochastic processes, and (iii) computation intensive simulations. We propose a new approach to carry out MC simulations. It makes use of simulation results obtained with systems of extremely small sizes. These system size dependent predictions, obtained at substantially reduced computational cost are used to construct results for system of infinite size. The approach is based on a new power law scaling that we have found in this work. An efficient implementation of MC simulation for time dependent rate processes is also developed. In this method, an additional variable is introduced for inter-event evolution. It increases the number of differential equation by one, but significantly reduces the computational effort required to estimate the interval of quiescence for time dependent rate processes. All the above ideas are combined in the new approach to simulate complete size distribution for simultaneous nucleation and growth of nanoparticles for a system of infinite size from erroneous simulations carried out with three extremely small size systems. A new framework for solving multidimensional population balance equations (PBEs) which routinely arise in modeling of nanoparticle synthesis is also developed. The new framework advances the concept of minimal internal consistency of discretization. It suggests that an n dimensional PBE is a statement of evolution of population of particles while accounting for how n internal attributes of particles change in particulate events. Thus, a minimum of n + 1 attributes of particles, instead of 2n attributes used hitherto, need to be represented perfectly in discrete representation. This is termed as the concept of minimum internal consistency of discretization in this work. The elements used for discretization should therefore be triangles for 2-d, tetrahedrons for 3-d, and an object with n + 1 vertices in n-d space for the solution of a n-d PBE. The results presented for the solutions for 2-d and 3-d PBEs show the superiority of this framework over the earlier framework. The present work also shows that directionality of elements plays a critical role in the solution of multi-dimensional PBEs. A mere change in connectivity of pivots in space, which changes their directionality, is shown to influence numerical results. This work led to new radial discretization of space, which has been followed up by others in the group and demonstrated to be quite powerful. A physical model is developed to understand digestive ripening of nanoparticles, a technique which is in extensive use in the literature to improve monodispersity of nanoparticles. The physical model is based on critical analysis of the large body of experimental findings available in the literature on several variations of this technique. The physical model is the first one to consistently and qualitatively explain all the reported experimental findings.

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