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PURPOSE. To evaluate light scatter and stray light in intraocular lenses (IOLs) explanted because of postoperative opacification (13 calcified hydrophilic acrylic, 1 calcified silicone, and 4 polymethylmethacrylate [PMMA] lenses with snowflake degeneration), as well as effect of opacification on other optical quality/performance indicators, in comparison with controls. METHODS. The Complete Angle Scatter Instrument (CASI) scatterometer was used to measure the forward light scattering (FLS) of the IOLs, and the stray light values at various angles were calculated from the measured FLS. Modulation transfer function (MTF) was obtained with an optical bench, and a Badal optometer was used to obtain letter chart images through the lenses. Back light scatter and light transmittance were also measured. RESULTS. Average stray light values (Log (s)) at a scattered angle of 100 were 1.79 +/- 0.37 for hydrophilic acrylic IOLs (controls 0.36 +/- 0.05), 1.53 for the silicone lens (control 0.41), and 1.62 +/- 0.46 for PMMA IOLs (control 0.25). Stray light was significantly higher for explanted opacified lenses (N = 18) in comparison with controls (N = 7; two-tail P < 0.001 at 100). Modulation transfer function and Badal image contrast were drastically reduced in lenses with calcification and snowflake degeneration. CONCLUSIONS. Different studies described the impact of stray light in human vision, with serious hindrance above 1.47 Log (s). Lenses explanted from patients because of clinically significant opacification are associated with a considerable increase in light scatter and stray light, as well as with a decline of other optical quality/performance indicators.

Made available in DSpace on 2017-07-24T19:45:52Z (GMT). No. of bitstreams: 1 Gustavo Trierveiler Anselmo.pdf: 9979848 bytes, checksum: 860bb544a69cc5a636999f5a0f91c142 (MD5) Previous issue date: 2016-09-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Simulator Didactics of Accommodation of the Human Eye is a set of activities that have as objective facilitate the teaching-learning process on optics and, especially, on the process of human accommodation. The educational product explores concepts of geometrical optics (light rays and refraction) in the paraxial approximation and its applications to spherical lenses. Didactic simulator was built with a flexible lens, produced with a latex-made male condom filled with water. Its spherical shape, with a diameter of approximately , was compared with the theoretical model of the “ball lens”. We have experimentally determined its focal length ( and compared it with the corresponding theoretical value, obtaining a accuracy. The flexibility feature of this lens gives the possibility to simulate the accommodation process of the eye in two different situations: for diverging and parallel light beams, corresponding to objects near and far from the observer, respectively. These concepts were addressed in the educational spirit of the meaningful learning of David Ausubel. It has been proposed 4 lesson plans from the previous organizers (taught in 8 lessons), 1 lesson plan for application of the didactic simulator (3 lessons) and 2 meetings for application and discussion of the questionnaires (2 lessons), summing up 13 classes. We have used several resources: lectures, computer simulators, construction of one darkroom, dissection of the bull's-eye and a experimental apparatus produced by students. Adding to other support materials, these instruments facilitated the learning of content offered and the better understanding of the students. This is proven by the results obtained in 42 questionnaires applied. Of these, 24 were before and 18 after the application of the project. There has been an increase of ~200% in the number of hits in the second stage. The proposal has been applied in a class of 39 students, where we had a meaningful learning of over of the class. One should stress also the impact on students, who were more willing to learn, requiring better quality lessons, both in content and evaluation of them. / Esta dissertação descreve um conjunto de atividades realizadas com o objetivo de facilitar o processo de ensino-aprendizagem sobre a óptica e, principalmente, da acomodação do cristalino humano. O produto educacional gerado, chamado de Simulador Didático da Acomodação do Cristalino do Olho Humano, explora conceitos de óptica geométrica (raio de luz e refração) dentro da aproximação paraxial e suas aplicações em lentes esféricas. Para isso foi construído um aparato com uma lente flexível, produzida com preservativo masculino feito de látex preenchido com água. O seu formato esférico, com diâmetro de aproximadamente , foi comparado com o modelo teórico das “ball lens”. Determinamos experimentalmente sua distância focal ( que, comparado com seu valor teórico, tem uma acurácia de . Por ser flexível, foi possível simular o processo de acomodação do cristalino em dois casos: para feixes de luz divergentes e paralelos, simulando situações com objetos próximos e distantes do observador, respectivamente. Estes conceitos foram abordados conforme a concepção educacional da aprendizagem significativa de David Ausubel. Foram propostos quatro planos de aulas de organizadores prévios (ministrado em oito aulas), um plano de aula de aplicação do simulador didático (três aulas) e dois momentos para aplicação e discussão dos questionários (duas aulas), totalizando 13 aulas. Utilizou-se variados recursos: aulas expositivas, simuladores computacionais, construção de câmara escura, dissecação do olho de boi e aparatos experimentais produzidos pelos alunos. Aliados a materiais de apoio, esses instrumentos facilitaram a aprendizagem dos conteúdos ministrados e o melhor entendimento dos alunos. Isso é comprovado pelos resultados obtidos em 42 questionários aplicados. Destes, 24 foram antes e 18 depois da aplicação do projeto. Houve um aumento de ~200% no número de acertos na segunda etapa. A proposta foi aplicada em uma turma de 39 alunos, onde obtivemos uma aprendizagem significativa de mais da classe. A ressaltar, também o impacto nos alunos, que se mostraram mais dispostos a aprenderem, exigindo aulas de melhor qualidade, tanto na exposição do conteúdo como na avaliação.

The demand of digital cameras in Taiwan has been steady increasing during 2011 to 2012; the total sales volumes are expected to be positive in the future. On other hand, due to consumers are pursuing higher quality lives, they buy more functionalities cameras. As DSLR cameras are too heavy and low-end digital cameras have low functionalities, which are why DSLR-like cameras and high-end digital cameras have become more popular recently. Despite the increase sale of cameras, the qualities of cameras accessories are still in chaos, especially in products like camera lens protector. There is no such a high C/P value of camera lens protector in the Taiwan market. Because of the above opportunity, some of my friends and I have founded a company to produce a high C/P value of camera lens protector. Our company vision is to product the best quality camera lens protector with medium price in Taiwan. Our company goal is to reach 50% market share in the camera accessories market. We have our own R&D in Taiwan, and guarantee that our products will be made in Taiwan. Our camera lens protector will be mainly sold in Taiwan in the beginning of year. About our channel selections, we will mainly focus on some independent stores in Bo-Han camera areas, two largest 3C chain stores. In order to sell our products to those independent and chain stores, pre-launching marketing is also needed. We will provide POSM to channels, incentives to sales people, and internet marketing to promote our products. When our products are steady in Taiwan, our company will be discovering more export sales in overseas. We are looking forward to doing OEM or ODM, if there were any opportunities in the future.

Cataract is a leading cause of blindness throughout the world, yet the fundamental biochemical causes are unknown. A rodent model of the biochemical processes is selenite cataract. This cataract shows some of the features of human cataracts such as increased lens calcium, proteolysis of proteins, and insolubilization leading to lens opacity. The goals of the current experiments were: (1) To measure changes in transcript levels for calpains and caspase 3 and oxidation of epithelial proteins in selenite cataract. (2) To elucidate changes in calpain 10 and its interaction with other calpains in selenite cataract. (3) To investigate changes in stability of ��B1-crystallin caused by deamidation and truncation. These data would provide roles for apoptosis, protein insolubilization, proteolysis and deamidation observed in cataract. To induce cataract, 12-day old rats were injected with an overdose of Na���SeO���. Epithelium was analyzed by competitive RT-PCR, zymography, and thiol-blotting. Calpains were detected by western-blotting. For ��B1-crystallin stability studies, recombinant ��B1-crystallins were denatured by urea or heat. Urea stability was measured by circular dichroism and fluorescence spectrometry, and heat stability was measured by light scattering at 405 nm. During selenite cataract formation, calpains in epithelium were activated resulting in increased proteolysis of crystallins, but mRNA levels for calpains did not show appreciable changes. Oxidation of sulthydryls in epithelial proteins was minimal during cataract formation. These results suggested that calpain-induced proteolysis in the epithelium contribute to selenite cataract. In selenite cataract, calpain 10 proteins disappeared, which appeared to be due to degradation by calpain 2 and Lp82 calpain. Deamidated ��B1-crystallin was less stable in urea and heat, compared to wildtype. When the terminal extensions were removed, ��B1-crystallin was as stable as wild-type. However, without the extensions, truncated ��B1-crystallin caused accelerated precipitation in a complex with ��A-crystallin, suggesting that the extensions may contribute to proper association with other crystallins and to stability of the soluble complexes. In summary, proteolysis of proteins by calpains was more pronounced than protein oxidation in lens epithelium of selenite cataract. Deamidation and truncation caused instability of ��B1-crystallin and abnormal association with ��A-crystallin. Thus, proteolysis and deamidation may increase susceptibility of lenses to cataract. / Graduation date: 2003

The increased risk of age-related cataracts in postmenopausal women and studies in animal models suggest that estrogen may have a protective role in the lens. However, very little is known regarding the role of estrogen and its receptors in the lens. To begin unraveling the estrogen signaling mechanism in the lens, the following aims were investigated: 1) to determine if estrogen receptors are expressed in the lens, [125I]-17beta-estradiol binding and mRNA expression of ERalpha, ERbeta, and GPR30 were examined in the mouse and human lens; 2) to determine if the loss of ERalpha and/or ERbeta receptors will induce spontaneous development of cataracts and to examine their role in an inducible cataract model; and 3) to identify estrogen-regulated genes in the lens that influence cataract development in the ERdelta3-induced cataract model. High-affinity, saturable binding sites for 17beta-estradiol were identified in the nuclear, cytosolic, and membrane fractions of the mouse and human lens. Additionally, detectable binding in the membrane fraction and expression of GPR30 mRNA in the mouse and human lens are the first evidence of this novel transmembrane estrogen receptor in the lens of any species. Transcripts for ERalpha, ERbeta, and GPR30 were expressed in the mouse lens which suggests that one or more of these estrogen receptor subtypes are responsible for the binding detected. With the loss of nuclear ER in the lens, spontaneous cataracts did not occur; however, diminished levels or loss of ERalpha in ERdelta3 female mice increased the severity of cortical cataracts with age. These results suggest that ERalpha in the lens may provide protection against the progression of cataracts in the ERdelta3 model. Together with the cataract induction and gene expression studies, six genes were identified to be differentially expressed with estrogen versus vehicle treatment in the lenses of ERdelta3 mice. The pax6, tcfap2a, tgfbeta2, six3, sox2, and pdgfalpha genes are known to have a critical role in lens development, proliferation, differentiation and maintenance of lens homeostasis. Therefore, future examination of these genes and their pathways in the lens may contribute to the understanding of the mechanisms of estrogen-mediated protection of lens transparency. Knowledge of pathways that function to maintain lens transparency and how estrogen regulated these pathways will assist in the development of estrogen therapies that can be clinically used to delay the onset and/or progression of cataracts. / Mylan School of Pharmacy and the Graduate School of Pharmaceutical Sciences; / Pharmacology-Toxicology / PhD; / Dissertation;

The crystalline lens is a unique cellular organ that performs metabolic processes while maintaining optical functionality. Mitochondria play a vital role in providing the cell with the energy necessary for these metabolic processes and have recently been shown to be more metabolically active than previously thought. To test the hypothesis that mitochondrial function directly influences the optical function of the lens, bovine lenses were treated with 50 μM, 200 μM, 600 μM and 1000 μM menadione, a mitochondrial specific toxin that renders the mitochondria inactive, and the Back Vertex Distance (BVD) variability was observed over 216 hours. Confocal micrographs of secondary fibre cells’ mitochondria were also analyzed for 50 μM, 200 μM, and 600 μM menadione treatment over 48 hours. Increase in BVD variability (± s.e.m.) was observed within 24 hours from 0.28 ± 0.021 to 1.83 ± 0.75 for the 600 μM treated lenses. Confocal micrograph analysis showed a trend toward a decrease in the average length of mitochondria from 7.9 ± 0.8 to 3.7 ± 0.9 over for 200 μM treated lenses and from 5.9 ± 1.0 to 3.6 ± 0.6 for the 600 μM treated lenses over 48 hours. These data show that indeed menadione has a detrimental effect on mitochondria as a function of both time and concentration and this change in mitochondria precedes changes in BVD variability directly linking mitochondrial function to optical function.