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The design and analysis of a rotman lens with reduced conjugate-port couplingIbbotson, Alex 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This project comprises the design, analysis, and construction of a Rotman lens with
reduced conjugate-port coupling. The Rotman lens is a beam-forming network, used
in wide-angle scanners to feed an antenna array. The scanning operation is based on
optics and is therefore frequency invariant, a desirable feature of the Rotman lens
compared to other beam-forming networks which employ phase shifters.
The antenna array is connected to the lens's array ports via transmission lines.
These array ports lie on the array contour which is designed so that a signal incident
onto the antenna array will propagate into the lens and focus at a particular point.
The position of this focal point depends on the signals direction of arrival at the
array. Ports are placed on these focal points to feed and receive signals. Bootlace
lenses allow up to four focal points for linear arrays whereas the Rotman lens is
designed for three foci. Scanners usually require to scan many beam-widths, thus
ports are employed along a focal arc which intersect these foci. Inter-focal ports do
not focus perfectly and result in phase errors distributed across the array aperture.
The derivation of three and four foci lenses is provided. There are several degrees
of freedom at the designer's disposal, the e ect which these available parameters have
on the lens geometry and phase errors is investigated. The waveguide implementa-
tion of these lenses is examined, in which we use vertically polarised horns as feed
ports and coaxial probes as array ports.
Some designs of Rotman lenses published in literature show excess mutual cou-
pling between symmetrically opposed feed ports. Using a model which approximates
the array contour as a re
ecting wall, we show that this is due to the re
ected energy
focusing on conjugate ports. It is identi ed that Rotman lenses designed for mini-
mum phase errors will have near maximum conjugate-port coupling. Two Rotman lenses have been designed at 3; 5GHz for ve feed ports, eleven
elements, and up to 30 scan angles. The rst is designed for minimum phase
errors, and the second for the defocusing of the re
ected energy from the focal
arc. Simulations show up to a 10dB reduction in conjugate-port coupling for the
second lens with a negligible degradation in performance from the phase errors.
Measurements show that the re
ected energy is spread between the feed ports as
expected, compared to the focusing at a single port of the traditional Rotman lens. / AFRIKAANSE OPSOMMING: Hierdie projek behels die ontwerp, analise en konstruksie van 'n Rotmanlens met
verminderde simmetries oorstaande poort koppeling. Die Rotmanlens is 'n patroon-
vormingsnetwerk wat gebruik word as samestellingvoer in wye hoek skandeerders.
'n Gewensde eienskap van die Rotmanlens bo faseskuif voernetwerke is dat die skan-
deerwerking gebasseer is op optika en dus frekwensie onafhanklik is.
Die antennasamestelling word deur transmissielyne verbind aan die antennapoorte
van die lens. Hierdie poorte l^e op die samestellingkontoer wat ontwerp is om te
verseker dat seine wat inval op die antennasamestelling sal voortplant in die lens en
fokus op 'n spesi eke punt. Die posisie van die fokuspunt hang af van die invalshoek
van die sein op die samestelling. Poorte word op hierdie fokuspunte geplaas om te
seine te ontvang en te lanseer. Hierdie tipe lense kan tot vier fokuspunte h^e , waar
die Rotman lens spesi ek vir drie fokuspunte ontwerp word. Skandeerders moet
normaalweg etlike bundelwydtes wyd kan skandeer, en daarom word poorte geplaas
op 'n straal wat die fokuspunte onderskep. Poorte wat weg van die fokus geplaas
word toon 'n e ens uit fokus gedrag, wat vertaal na fasefoute in die samestelling
stralingsvlak.
Die a
eiding van drie en vier fokus lense word verskaf. Daar is verskeie grade
van vryheid tot die beskikking van die ontwerper, en die e ek wat die beskikbare
parameters op die geometrie van die lens en die fase foute het word ondersoek. Die
gol
eier implimetering van hierdie lense word beskryf, waar vertikaal gepolariseerde
horings as voerpoorte, en ko-aksiale lyne as antennapoorte gebruik word. Sommige Rotman lens ontwerpe in die literatuur toon beduidende koppeling
tussen die simmetries oorstaande voerpoorte. Deur van 'n model gebruik te maak
wat die samestellingkontoer as 'n weerkaatsende muur benader toon ons aan dat
die koppeling geskied as gevolg van die weerkaatsde energie wat fokus in die simme-
tries oorstaande poorte. Dit word identi seer dat Rotman lense wat vir minimum
fasefoute ontwerp word bykans maksimum koppeling tussen simmetries oorstaande
poorte tot gevolg het.
Twee Rotman lense is ontwerp by 3; 5GHz vir vyf voerpoorte, elf antenna ele-
mente en skandeer hoeke van 30. Die eerste is ontwerp vir minimum fasefoute en
die tweede vir uit fokus weerkaatsde energie vanuit die fokus straal. Simulasies toon tot 10 dB vermindering in koppeling tussen simmetries oorstaande poorte vir die
tweede lens met weglaatbare werkverrigting verswakking as gevolg van fasefoute.
Metings toon dat die weerkaatsde energie, soos verwag, versprei word tussen die
voerpoorte vergeleke met energie gefokus in 'n enkele poort soos by die tradisionele
Rotman lens.
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Mikroskopie pomalými elektrony ve studiu složitých krystalických struktur / STUDY OF COMPLICATED CRYSTAL STRUCTURES BY MEANS OF SLOW ELECTRONSMikmeková, Šárka January 2013 (has links)
Methods for examination of the crystal structure of crystalline materials include the X-Ray, neutron and synchrotron-radiation diffraction, electron backscattered diffraction in the scanning electron microscope, scanning transmission electron microscopy, transmission electron microscopy and focused ion beam microscopy. The scanning low energy electron microscopy (SLEEM) is less known as yet but already has proven itself very powerful tool for studies of the crystal lattice. By means of very slow electrons reflected from the sample and effectively detected in their full angular and energy distribution the crystalline structure is imaged at high spatial resolution and high contrast is obtained between differently oriented grains in polycrystals. Because of high sensitivity of the image signal to the inner potential distribution in the sample even details like subgrains or twins as well as strain at the microstructural level can be visualized. The aim of this thesis is to demonstrate the scanning low energy electron microscopy as an effective tool for investigation of wide range of materials like steels, non-ferrous alloys and ultra-fine grained materials.
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Modeling and model-aware signal processing methods for enhancement of optical systemsAksoylar, Aydan 05 November 2016 (has links)
Theoretical and numerical modeling of optical systems are increasingly being utilized in a wide range of areas in physics and engineering for characterizing and improving existing systems or developing new methods. This dissertation focuses on determining and improving the performance of imaging and non-imaging optical systems through modeling and developing model-aware enhancement methods. We evaluate the performance, demonstrate enhancements in terms of resolution and light collection efficiency, and improve the capabilities of the systems through changes to the system design and through post-processing techniques. We consider application areas in integrated circuit (IC) imaging for fault analysis and malicious circuitry detection, and free-form lens design for creating prescribed illumination patterns.
The first part of this dissertation focuses on sub-surface imaging of ICs for fault analysis using a solid immersion lens (SIL) microscope. We first derive the Green's function of the microscope and use it to determine its resolution limits for bulk silicon and silicon-on-insulator (SOI) chips. We then propose an optimization framework for designing super-resolving apodization masks that utilizes the developed model and demonstrate the trade-offs in designing such masks. Finally, we derive the full electromagnetic model of the SIL microscope that models the image of an arbitrary sub-surface structure.
With the rapidly shrinking dimensions of ICs, we are increasingly limited in resolving the features and identifying potential modifications despite the resolution improvements provided by the state-of-the-art microscopy techniques and enhancement methods described here. In the second part of this dissertation, we shift our focus away from improving the resolution and consider an optical framework that does not require high resolution imaging for detecting malicious circuitry. We develop a classification-based high-throughput gate identification method that utilizes the physical model of the optical system. We then propose a lower-throughput system to increase the detection accuracy, based on higher resolution imaging to supplement the former method.
Finally, we consider the problem of free-form lens design for forming prescribed illumination patterns as a non-imaging application. Common methods that design free-form lenses for forming patterns consider the input light source to be a point source, however using extended light sources with such lenses lead to significant blurring in the resulting pattern. We propose a deconvolution-based framework that utilizes the lens geometry to model the blurring effects and eliminates this degradation, resulting in sharper patterns.
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Testes oftalmológicos e poder dióptrico da lente intraocular em lobo guará (Chrysocyon brachyurus - Illinger, 1815)Barros, Rodrigo. January 2018 (has links)
Orientador: Cláudia Valéria Seullner Brandão / Resumo: Este trabalho tem como objetivo descrever valores oftalmológicos, determinar o poder dióptrico da lente intraocular (LIO), além de comparar os olhos considerando a lateralidade e sexo nesta espécie e avaliar a hipótese que os valores são similares com o cão. O lobo guará (Chrysocyon brachyurus) encontra-se na lista vermelha de espécies em extinção do The International Union for Conservation of Nature (IUCN), de animais em quase ameaça. As principais causas são a caça indiscriminada e atropelamentos. A espécie possui hábitos noturnos e crepusculares, o que torna a visão um dos seus sentidos mais importantes. Diante disso, a pesquisa avaliou 13 lobos guarás (26 olhos), hígidos, com idade superior a um ano, machos e fêmeas com peso entre 25 e 30kg. Foram realizados os seguintes testes oftalmológicos: teste lacrimal de Schirmer (TLS), estesiometria, tonometria e paquimetria. Adicionalmente, foi realizada a ultrassonografia modo A (US-A), ceratometria e a medida da distância limbo-limbo; e o calculo da dioptria lenticular. Foram obtidos os seguintes valores médios para os testes oftalmológicos: TLS 19,15±3,58mm/min; estesiometria 0,96±0,31mm; tonometria 13,96±4,75mmHg; paquimetria 528,50±55,13µm; distância limbo-limbo 18,08±1,32mm; comprimento axial 21,04±0,55mm e profundidade de câmara anterior 4,63±0,33mm; e cetarometria média 37,21±1,32D. Referente às fórmulas: SRK/T 34,04±1,66D; Hoffer Q 36,31±1,83D; Holladay I 35,42±1,88D, Haigis 42,19±2,29D e Holladay II 35,00±1,65D. Foram d... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed to describe ophthalmologic values, to determine the dioptric power of the intraocular lens (IOL), and to evaluate the results compared to the laterality of the eyes and the sex of maned wolves and evaluate the hypothesis that the values are similar to dogs. The maned wolf (Chrysocyon brachyurus) is in the red list of endangered species of the International Union for Conservation of Nature (IUCN), a near-threatened animal. The main causes are indiscriminate hunting and trampling. The species has nocturnal and crepuscular habits, which makes the vision one of its most important senses. In this research were evaluated 13 maned wolfs (26 eyes), healthy, captive wolves, aged from 1 to 8 years, four males and nine females with weight between 25 and 30kg. The following ophthalmological tests were performed: Schirmer's lachrymal test (SLT), esthesiometry, tonometry and pachymetry. Additionally, ultrasound mode A, keratometry and measurement of limbo-limbo distance were performed; and the calculation of lenticular diopter. Values of the ophthalmological tests were obtained: SLT 19,15±3,58mm/min; esthesiometry 0,96±0,31mm; tonometry 13,96±4,75mmHg; pachymetry 528,50±55,13μm; limbo-limbo distance 18,08±1,32mm; axial length 21,04±0,55mm and anterior chamber depht 4,63±0,33mm. Cetarometry average 37,21±1,32D. The formulas: SRK/T 34,04±1,66D; Hoffer Q 36,31±1,83D; Holladay I 35,42±1,88D, Haigis 42,19±2,29D and Holladay II 35,00±1,65D. The ophthalmologic variables and diopt... (Complete abstract click electronic access below) / Doutor
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Strahlenbelastung der Augenlinse bei urologischen Eingriffen am Beispiel der ureterorenoskopischen Steinbehandlung / Eye lens radiation exposure at the example of the ureteroscopic stone therapySabo, Ana 25 September 2018 (has links)
No description available.
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Dosimetria clínica em exame periapical utilizando diferentes colimadoresTravessas, Juliana Andréa Corrêa January 2008 (has links)
Exames radiográficos para fins de saúde constituem a principal fonte de exposição da população à radiação ionizante artificial, devendo empregar a dose mínima necessária para que se obtenha imagem de qualidade. Colimadores retangulares têm sido propostos em substituição aos circulares para reduzir a exposição de órgãos críticos. Este estudo teve por objetivo verificar se existe diferença na dose de radiação nas regiões de cristalino e tireóide durante a realização de um exame periapical completo, em função da forma e do tamanho do colimador utilizado. Trinta pacientes foram aleatoriamente distribuídos em três grupos: 1 - colimador circular convencional com 60 mm de diâmetro; 2 - colimador retangular com 24 x 32 mm² e 3 - colimador retangular com 30 x 40 mm2. As condições de exame foram padronizadas para os três grupos. A dose foi obtida por meio de dosímetros termoluminescentes de LiF:Mg.Cu.P (TLD-100H), que permaneceram, durante a execução das 14 radiografias do exame completo periapical, posicionados sobre os olhos (cristalino) direito e esquerdo e sobre a região da tireóide, abaixo do protetor plumbífero. Os resultados finais foram submetidos aos testes não-paramétricos de Kruskal-Wallis e Friedman, ambos complementados por seus testes de comparações múltiplas, ao nível de significância de 5%. No grupo 2 houve redução significativa na dose de radiação absorvida na região dos olhos em relação aos grupos 1 e 3. Os grupos 2 e 3 apresentaram redução significativa na dose de radiação absorvida na tireóide em relação ao grupo 1. Nos três grupos, a dose absorvida na região dos olhos é significativamente maior do que a dose absorvida pela tireóide. O uso do colimador retangular reduziu significativamente a dose absorvida na tireóide. / X rays examinations are the main source of population's exposure to artificial ionizing radiation. Radiation dose in such examinations should be as low as possible but still ensuring a good image quality. Rectangular collimators have been proposed in substitution to the circular ones in order to minimize the radiation exposure to nearby critical organs. This study aims to compare the radiation doses in the lens of the eyes (right and left) and thyroid gland obtained using different collimators, in a complete periapical examination (14 radiographic exposures). Thirty patients have been randomly allocated to three groups: 1 - using a 60 mm diameter conventional circular collimator; 2 - using a 24 x 32 mm² rectangular collimator; and 3 - using a 30 x 40 mm2 rectangular collimator. The doses were measured by LiF:Mg,Cu,P thermoluminescent dosimeters (TLD-100H) positioned over both right and left eyes and under the lead thyroid protector shield, in the thyroid gland position. Final results were submitted to Kruskal-Wallis and Friedman non-parametric statistics analysis, complemented by multiple comparison tests, with 5% significance level. Group 2 presented a significant dose reduction in the eyes region compared to groups 1 and 3. Groups 2 and 3 showed a significant dose reduction in the thyroid gland region compared to group1.
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Modélisation hyperfréquence de problèmes multi-échelles appliquée au cas des antennes à métamatériaux diélectriques / Microwave modeling of multi-scale problems applied to dielectric metamaterial antennasDiallo, Alpha Ousmane 30 October 2017 (has links)
Ce travail de thèse s’intéresse à l’amélioration de la compacité des antennes destinées en priorité aux systèmes embarqués tout en respectant les exigences de performance et de compétitivité. L’approche explorée consiste à utiliser des matériaux artificiels fonctionnant en transmission et conçus en structurant la matière diélectrique à une échelle plus petite que la longueur d’onde (sub-longueur d’onde). Cette structuration permet en pratique d’opérer une variation de l’indice de réfraction effectif afin de réaliser des éléments diffractifs aptes à remplir une fonction hyperfréquence. Cependant, la particularité de ce type d’élément structuré est de mêler plusieurs échelles physiques engendrant une complexité dans leur étude. La plus grande dimension d’un composant structuré peut atteindre plusieurs dizaines de longueur d’onde, par exemple 20λ, alors que la taille minimale des structures sub-longueur d’onde peut être inférieure à une fraction de la longueur d’onde, tel que λ/20. Cet aspect multi-échelle allonge les temps de simulation des dispositifs antennaires intégrant ces éléments structurés, empêchant ainsi toute possibilité d’optimisation multi-paramètres dans des temps raisonnables. Afin de pouvoir exploiter pleinement le potentiel de ces matériaux structurés, un modèle numérique de calcul a été développé sur la base des chemins optiques. Ce modèle restitue des résultats sur le maximum de gain des antennes lentilles diffractives structurées avec une précision de 0,5 dB. Le temps de calcul du modèle est de l’ordre de la minute comparée à plus de 6 heures pour une simulation complète avec le logiciel de calcul électromagnétique CST. La rapidité et la précision de ce modèle ont été mises à profit pour optimiser la conception d’une lentille diffractive structurée. Pour illustrer la pertinence de cette approche structurée, ses performances ont été comparées à celles des antennes lentilles de Fresnel et à profil hyperbolique. Cette comparaison s’est faite dans des conditions d’encombrement identiques avec un rapport longueur sur diamètre L/D de 0,5. Le gain de la lentille structurée se révèle être plus élevé de 1,6 dB par rapport à celui de la lentille de Fresnel et de 2,7 dB par rapport à celui de la lentille hyperbolique. / This work focuses on the improvement of the antennas compactness used primarily for embedded systems while respecting the performance and competitiveness requirements. The approach explored consists in using artificial materials operating in transmission and designed by structuring the dielectric material on a scale smaller than the wavelength (sub-wavelength). This structuring makes it possible in practice to achieve a variation in the effective refractive index in order to produce diffractive elements capable of performing a microwave function. However, the particularity of this type of structured element is to mix several physical scales generating complexity in their study. The largest dimension of a structured component can reach several tens of wavelength, for example 20λ, while the minimum size of the sub-wavelength structures may be less than a fraction of the wavelength, as than λ / 20. This multi-scale aspect increases the simulation times of antenna devices integrating these structured elements, thus preventing any possibility of multi-parameter optimization in reasonable times. In order to exploit fully the potential of these structured materials, a numerical model of computation has been developed on the basis of optical paths. This model gives results on the maximum gain of structured diffractive lens antennas with an accuracy of 0.5 dB. The computation time of the model is of the order of the minute compared to more than 6 hours for a complete simulation with the electromagnetic calculation software CST Microwave Studio. The speed and precision of this model have been used to optimize the design of a structured diffractive lens. To illustrate the relevance of this structured approach, its performances were compared with those of Fresnel lens antenna and hyperbolic lens antenna. This comparison was carried out under identical footprint conditions with a length to diameter ratio L / D of 0.5. The gain of the structured lens was found to be 1.6 dB higher than the Fresnel lens and 2.7 dB higher than the hyperbolic lens.
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Dosimetria clínica em exame periapical utilizando diferentes colimadoresTravessas, Juliana Andréa Corrêa January 2008 (has links)
Exames radiográficos para fins de saúde constituem a principal fonte de exposição da população à radiação ionizante artificial, devendo empregar a dose mínima necessária para que se obtenha imagem de qualidade. Colimadores retangulares têm sido propostos em substituição aos circulares para reduzir a exposição de órgãos críticos. Este estudo teve por objetivo verificar se existe diferença na dose de radiação nas regiões de cristalino e tireóide durante a realização de um exame periapical completo, em função da forma e do tamanho do colimador utilizado. Trinta pacientes foram aleatoriamente distribuídos em três grupos: 1 - colimador circular convencional com 60 mm de diâmetro; 2 - colimador retangular com 24 x 32 mm² e 3 - colimador retangular com 30 x 40 mm2. As condições de exame foram padronizadas para os três grupos. A dose foi obtida por meio de dosímetros termoluminescentes de LiF:Mg.Cu.P (TLD-100H), que permaneceram, durante a execução das 14 radiografias do exame completo periapical, posicionados sobre os olhos (cristalino) direito e esquerdo e sobre a região da tireóide, abaixo do protetor plumbífero. Os resultados finais foram submetidos aos testes não-paramétricos de Kruskal-Wallis e Friedman, ambos complementados por seus testes de comparações múltiplas, ao nível de significância de 5%. No grupo 2 houve redução significativa na dose de radiação absorvida na região dos olhos em relação aos grupos 1 e 3. Os grupos 2 e 3 apresentaram redução significativa na dose de radiação absorvida na tireóide em relação ao grupo 1. Nos três grupos, a dose absorvida na região dos olhos é significativamente maior do que a dose absorvida pela tireóide. O uso do colimador retangular reduziu significativamente a dose absorvida na tireóide. / X rays examinations are the main source of population's exposure to artificial ionizing radiation. Radiation dose in such examinations should be as low as possible but still ensuring a good image quality. Rectangular collimators have been proposed in substitution to the circular ones in order to minimize the radiation exposure to nearby critical organs. This study aims to compare the radiation doses in the lens of the eyes (right and left) and thyroid gland obtained using different collimators, in a complete periapical examination (14 radiographic exposures). Thirty patients have been randomly allocated to three groups: 1 - using a 60 mm diameter conventional circular collimator; 2 - using a 24 x 32 mm² rectangular collimator; and 3 - using a 30 x 40 mm2 rectangular collimator. The doses were measured by LiF:Mg,Cu,P thermoluminescent dosimeters (TLD-100H) positioned over both right and left eyes and under the lead thyroid protector shield, in the thyroid gland position. Final results were submitted to Kruskal-Wallis and Friedman non-parametric statistics analysis, complemented by multiple comparison tests, with 5% significance level. Group 2 presented a significant dose reduction in the eyes region compared to groups 1 and 3. Groups 2 and 3 showed a significant dose reduction in the thyroid gland region compared to group1.
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Development of a novel gradient-force tapered fibre optical tweezers system for 3D optical trapping at near horizontal fibre insertion anglesRoss, Steven January 2015 (has links)
The use of optical fibre as a mechanism for the delivery of the trapping laser beam to the sample chamber significantly reduces both the size and the build costs of “Optical Tweezers”. Furthermore, the use of fibre facilitates the decoupling of the optical trapping beam from the microscope optics, which provides further scope for the development of a portable optical trapping system, and the potential for uncomplicated integration with other advanced microscopy systems such as an atomic force microscope (AFM) for example. For use with an AFM, the optical fibre must be inserted at an angle of 10° with respect to the sample chamber floor. However, previous literature suggests that 3D optical trapping with a single fibre inserted at an angle ≤20° is not feasible. This thesis presents the design, development, build and test of a single beam optical fibre based gradient force optical tweezers system and its associated software. An investigation is conducted to ascertain why optical trapping, using single fibre systems, cannot be achieved at sub 20° insertion angles, the result of which formed the basis of a hypothesis that explains this limitation. This finding led to the development of tapered optical fibre tips that are cable of 3D optical trapping at an insertion angle of ≤10°. The optimised optical fibre tapers are presented and their ability to trap both organic and inanimate material in 3D at an insertion angle of 10° is demonstrated. The near-horizontal insertion angle introduced a maximum trapping range (MTR). The MTR of the tips is determined empirically, evaluated against simulated data, and found to be tuneable through taper optimisation. Optical trap characterisation has been undertaken in terms of the optical trapping forces acting on the trapping subjects. Finally, the fibre tapering devices ability to reproduce identical tapers, or not, using the same device parameters, was investigated and the results in terms of geometric profile and optical performance are presented.
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Avaliação morfológica e molecular do epitélio e cápsula anterior da lente de cães com catarata, submetidos à facoemulsificação com o uso do azul de tripano a 0,1% / Morphologic and molecular evaluation of the epithelium and anterior capsule of the canine lens, with cataracts, after surgery utilizing 0.1% trypan blue during capsulorrexisAna Paula Franco do Amaral Hvenegaard 31 March 2015 (has links)
A remoção cirúrgica da catarata é uma intervenção cada vez mais praticada na medicina veterinária e, com ela, diversos estudos têm sido realizados com o intuito de reduzir as possíveis complicações de seu pós-operatório, tal como a opacidade da cápsula posterior, alteração ocasionada principalmente pela diferenciação e migração das células do epitélio lenticular para a cápsula posterior da lente. O objetivo deste estudo foi analisar a morfologia da cápsula anterior e seu epitélio pela coloração de rotina com hematoxilina-eosina; a composição molecular da cápsula pelas técnicas histoquímicas de PAS (avaliação de proteoglicanos) e picrosirius red (avaliação de colágeno IV); além da expressão de morte celular nas células epiteliais pelas técnicas de imunofluorescência com Beclina 1 (autofagia) e Caspase 3 (apoptose), em cães idosos com catarata diabética e não diabética do tipo hipermadura, submetidos ao uso ou não de azul de tripano a 0,1 % durante a cirurgia de remoção da catarata por facoemulsificação. Para o estudo, foram estudadas as células epiteliais e cápsula anterior da lente de 27 cães, sendo 21 fêmeas e 6 machos, de 8 a 12 anos de idade (média = 9,6 anos), de diversas raças, que foram primeiramente divididos em 2 grupos: GC (catarata hipermadura) e GCD (catarata diabética) e, depois, subdivididos em outros 4 grupos: os que utilizaram o corante: GAND (catarata hipermadura com azul de tripano) e GAD (catarata diabética com azul de tripano); e os que não foram submetidos ao uso do corante: GND (catarata hipermadura sem azul de tripano) e GD (catarata diabética sem azul de tripano). Os resultados das análises realizadas observaram que ambas as amostras, tanto as provenientes das cataratas hipermaduras, quanto as diabéticas, sofrem alterações em igual intensidade apesar do diferente processo de formação, ou seja, observou-se que houve positividade na expressão de morte celular do epitélio por apoptose e autofagia em igual intensidade e independente da utilização de azul de tripano a 0,1 % em todos os grupos; que a composição molecular da cápsula quanto à quantidade de proteoglicanos e colágeno IV também é semelhante e que, apesar da cápsula apresentar-se mais espessada do que o normal, ainda preserva sua relação anatômica com o epitélio. Conclui-se, portanto, que as lesões ocasionadas pela formação da catarata diabética e hipermadura no epitélio e em sua membrana basal (cápsula) são semelhantes apesar da diferente fisiopatologia de formação, mas que o epitélio e a cápsula ainda preservam sua relação anatômica e morfologia. Com os resultados, também se pode sugerir que cães que apresentem cataratas destes tipos, devam apresentar menor risco de ocorrência de opacidade na cápsula posterior no pós cirúrgico da catarata / Nowadays, surgical removal of cataracts in dogs is being considered a common intervention. Along with that, many studies have been realized aiming to reduce its post operatory complications, such as the posterior lens capsule opacity, which occurs due to epithelium cells differentiation and migration to the posterior pole. The objective of this study was to evaluate, by morphometry (hematoxilin-eosin), histochemistry (PAS and picrosirius red) and immunofluorescence (Caspase 3 and Beclin 1) analysis: the morphological alterations of the lens anterior capsule and its epithelium; the molecular components of the extracellular matrix; and the expression of lens epithelium cellular death (by autophagy and apoptosis), in elderly diabetic and non diabetic dogs with cataracts, after phacoemulsification surgery utilizing or not 0,1 % trypan blue. Twenty seven dogs, including 21 female and 6 male dogs, with ages varying from 8 to 12 years old (mean = 9.6 yo), of different breeds were studied. Animals were first divided into 2 groups: GC (hypermature cataracts) and GCD (diabetic cataracts); then, subdivided in 4 different groups: GAND (non diabetic dogs with trypan blue), GAD (diabetic dogs with trypan blue), GND (non diabetic dogs without trypan blue) and finally, GD (diabetic dogs without trypan blue). Results showed that both types of studied samples (diabetic and hypermature ones), are equally altered besides its different pathophysiology, since no statistical significant differences were observed in both capsule and epithelium thickness, type IV collagen and proteoglycans concentration and also, in the epithelium cells autophagy and apoptosis, observed by Caspase 3 and Beclin 1 expression in every studied group. In addition, 0,1 % trypan blue was not capable to demonstrate its toxicity rate, as cells were already under the referred death processes. In conclusion, our findings suggests that, besides the differences in both, hypermature and diabetic cataracts, pathophysiologies of formation, serious and similar alterations are observed with the same intensity in the anterior lens capsule and its epithelium in dogs, what must probably reduce posterior lens capsule opacity post phacoemulsification surgery
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