Relevant bibliographies by topics / OLCO model

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Academic literature on the topic 'OLCO model'

Author: Grafiati
Published: 4 June 2021
Last updated: 2 February 2022

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Journal articles on the topic "OLCO model"

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Voskuhl, Rhonda R., Noriko Itoh, Alessia Tassoni, Macy Akiyo Matsukawa, Emily Ren, Vincent Tse, Ellis Jang, Timothy Takazo Suen, and Yuichiro Itoh. "Gene expression in oligodendrocytes during remyelination reveals cholesterol homeostasis as a therapeutic target in multiple sclerosis." Proceedings of the National Academy of Sciences 116, no. 20 (April 30, 2019): 10130–39. http://dx.doi.org/10.1073/pnas.1821306116.

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Regional differences in neurons, astrocytes, oligodendrocytes, and microglia exist in the brain during health, and regional differences in the transcriptome may occur for each cell type during neurodegeneration. Multiple sclerosis (MS) is multifocal, and regional differences in the astrocyte transcriptome occur in experimental autoimmune encephalomyelitis (EAE), an MS model. MS and EAE are characterized by inflammation, demyelination, and axonal damage, with minimal remyelination. Here, RNA-sequencing analysis of MS tissues from six brain regions suggested a focus on oligodendrocyte lineage cells (OLCs) in corpus callosum. Olig1-RiboTag mice were used to determine the translatome of OLCs in vivo in corpus callosum during the remyelination phase of a chronic cuprizone model with axonal damage. Cholesterol-synthesis gene pathways dominated as the top up-regulated pathways in OLCs during remyelination. In EAE, remyelination was induced with estrogen receptor-β (ERβ) ligand treatment, and up-regulation of cholesterol-synthesis gene expression was again observed in OLCs. ERβ-ligand treatment in the cuprizone model further increased cholesterol synthesis gene expression and enhanced remyelination. Conditional KOs of ERβ in OLCs demonstrated that increased cholesterol-synthesis gene expression in OLCs was mediated by direct effects in both models. To address this direct effect, ChIP assays showed binding of ERβ to the putative estrogen-response element of a key cholesterol-synthesis gene (Fdps). As fetal OLCs are exposed in utero to high levels of estrogens in maternal blood, we discuss how remyelinating properties of estrogen treatment in adults during injury may recapitulate normal developmental myelination through targeting cholesterol homeostasis in OLCs.
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Bharti, Dinesh, Si-Jung Jang, Sang-Yun Lee, Sung-Lim Lee, and Gyu-Jin Rho. "In Vitro Generation of Oocyte Like Cells and Their In Vivo Efficacy: How Far We have been Succeeded." Cells 9, no. 3 (February 27, 2020): 557. http://dx.doi.org/10.3390/cells9030557.

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In the last few decades, stem cell therapy has grown as a boon for many pathological complications including female reproductive disorders. In this review, a brief description of available strategies that are related to stem cell-based in vitro oocyte-like cell (OLC) development are given. We have tried to cover all the aspects and latest updates of the in vitro OLC developmental methodologies, marker profiling, available disease models, and in vivo efficacies, with a special focus on mesenchymal stem cells (MSCs), induced pluripotent stem cells (iPSCs), and embryonic stem cells (ESCs) usage. The differentiation abilities of both the ovarian and non-ovarian stem cell sources under various induction conditions have shown different effects on morphological alterations, proliferation- and size-associated developments, hormonal secretions under gonadotropic stimulations, and their neo-oogenesis or folliculogenesis abilities after in vivo transplantations. The attainment of characters like oocyte-like morphology, size expansion, and meiosis initiation have been found to be major obstacles during in vitro oogenesis. A number of reports have either lacked in vivo studies or have shown their functional incapability to produce viable and healthy offspring. Though researchers have gained many valuable insights regarding in vitro gametogenesis, still there are many things to do to make stem cell-derived OLCs fully functional.
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Muñoz-Pascual, Lucía, Carla Curado, and Jesús Galende. "Fuzzy Set Qualitative Comparative Analysis on the Adoption of Environmental Practices: Exploring Technological- and Human-Resource-Based Contributions." Mathematics 9, no. 13 (July 1, 2021): 1553. http://dx.doi.org/10.3390/math9131553.

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Our main objective was to analyze which paths can lead to the adoption of environmental practices (PRAC) in firms, for which we developed three original alternative research models. Model 1 involves five sources for the adoption of environmental practices: human resource costs, organizational learning capability, firm size, manager educational level and manager experience. Model 2 adopts five sources for PRAC: human resource costs, information technology support, firm size, manager educational level and manager experience. Finally, Model 3 adopts six sources for PRAC: human resource costs, organizational learning capability, information technology support, firm size, manager educational level and manager experience. Therefore, Model 1 uses the organizational learning capability for PRAC, Model 2 uses the information technology support for PRAC and Model 3 uses both organizational learning capability and information technology support for PRAC. We used a fuzzy set qualitative comparative analysis on 349 small- and medium-sized Portuguese firms in twelve industrial sectors. The results show that organizational learning capability (OLC) and information technology support (ITS) are important sources for the development of PRAC. In this line, the three research models show that there are different pathways that lead to PRAC. These research models also show pathways that lead to the absence of PRAC. Therefore, the qualitative findings show the relevancy of OLC and ITS to PRAC. In addition, our findings indicate that, by focusing on variables such as OLC, a firm can find more paths that lead to PRAC. Additionally, with the combination of OLC and ITS, it must be taken into account that only developing ITS without OLC is riskier when obtaining PRAC.
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Zhang, Fengji, Zhijiang Zhang, Yi Long, and Ling Zhang. "Integration of Sentinel-3 OLCI Land Products and MERRA2 Meteorology Data into Light Use Efficiency and Vegetation Index-Driven Models for Modeling Gross Primary Production." Remote Sensing 13, no. 5 (March 8, 2021): 1015. http://dx.doi.org/10.3390/rs13051015.

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Accurately and reliably estimating total terrestrial gross primary production (GPP) on a large scale is of great significance for monitoring the carbon cycle process. The Sentinel-3 satellite provides the OLCI FAPAR and OTCI products, which possess a higher spatial and temporal resolution than MODIS products. However, few studies have focused on using LUE models and VI-driven models based on the Sentinel-3 satellites to estimate GPP on a large scale. The purpose of this study is to evaluate the performance of Sentinel-3 OLCI FAPAR and OTCI products combined with meteorology reanalysis data in estimating GPP at site and regional scale. Firstly, we integrated OLCI FAPAR and meteorology reanalysis data into the MODIS GPP algorithm and eddy covariance light use efficiency (EC-LUE) model (GPPMODIS-GPP and GPPEC-LUE, respectively). Then, we combined OTCI and meteorology reanalysis data with the greenness and radiation (GR) model and vegetation index (VI) model (GPPGR and GPPVI, respectively). Lastly, GPPMODIS-GPP, GPPEC-LUE, GPPGR, and GPPVI were evaluated against the eddy covariance flux data (GPPEC) at the site scale and MODIS GPP products (GPPMOD17) at the regional scale. The results showed that, at the site scale, GPPMODIS-GPP and GPPEC-LUE agreed well with GPPEC for the US-Ton site, with R2 = 0.73 and 0.74, respectively. The performance of GPPGR and GPPVI varied across different biome types. Strong correlations were obtained across deciduous broadleaf forests, mixed forests, grasslands, and croplands. At the same time, there are overestimations and underestimations in croplands, evergreen needleleaf forests and deciduous broadleaf forests. At the regional scale, the annual mean and maximum daily GPPMODIS-GPP and GPPEC-LUE agreed well with GPPMOD17 in 2017 and 2018, with R2 > 0.75. Overall, the above findings demonstrate the feasibility of using Sentinel-3 OLCI FAPAR and OTCI products combined with meteorology reanalysis data through LUE and VI-driven models to estimate GPP, and fill in the gaps for the large-scale evaluation of GPP via Sentinel-3 satellites.
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Su, Hua, Xuemei Lu, Zuoqi Chen, Hongsheng Zhang, Wenfang Lu, and Wenting Wu. "Estimating Coastal Chlorophyll-A Concentration from Time-Series OLCI Data Based on Machine Learning." Remote Sensing 13, no. 4 (February 6, 2021): 576. http://dx.doi.org/10.3390/rs13040576.

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Chlorophyll-a (chl-a) is an important parameter of water quality and its concentration can be directly retrieved from satellite observations. The Ocean and Land Color Instrument (OLCI), a new-generation water-color sensor onboard Sentinel-3A and Sentinel-3B, is an excellent tool for marine environmental monitoring. In this study, we introduce a new machine learning model, Light Gradient Boosting Machine (LightGBM), for estimating time-series chl-a concentration in Fujian’s coastal waters using multitemporal OLCI data and in situ data. We applied the Case 2 Regional CoastColour (C2RCC) processor to obtain OLCI band reflectance and constructed four spectral indices based on OLCI feature bands as supplementary input features. We also used root-mean-square error (RMSE), mean absolute error (MAE), median absolute percentage error (MAPE), and R2 as performance indicators. The results indicate that the addition of spectral indices can easily improve the prediction accuracy of the model, and normalized fluorescence height index (NFHI) has the best performance, with an RMSE of 0.38 µg/L, MAE of 0.22 µg/L, MAPE of 28.33%, and R2 of 0.785. Moreover, we used the well-known band ratio and three-band methods for chl-a estimation validation, and another two OLCI chl-a products were adopted for comparison (OC4Me chl-a and Inverse Modelling Technique (IMT) Neural Net chl-a). The results confirmed that the LightGBM model outperforms the traditional methods and OLCI chl-a products. This study provides an effective remote sensing technique for coastal chl-a concentration estimation and promotes the advantage of OLCI data in ocean color remote sensing.
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Blix, Katalin, Károly Pálffy, Viktor Tóth, and Torbjørn Eltoft. "Remote Sensing of Water Quality Parameters over Lake Balaton by Using Sentinel-3 OLCI." Water 10, no. 10 (October 11, 2018): 1428. http://dx.doi.org/10.3390/w10101428.

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The Ocean and Land Color Instrument (OLCI) onboard Sentinel 3A satellite was launched in February 2016. Level 2 (L2) products have been available for the public since July 2017. OLCI provides the possibility to monitor aquatic environments on 300 m spatial resolution on 9 spectral bands, which allows to retrieve detailed information about the water quality of various type of waters. It has only been a short time since L2 data became accessible, therefore validation of these products from different aquatic environments are required. In this work we study the possibility to use S3 OLCI L2 products to monitor an optically highly complex shallow lake. We test S3 OLCI-derived Chlorophyll-a (Chl-a), Colored Dissolved Organic Matter (CDOM) and Total Suspended Matter (TSM) for complex waters against in situ measurements over Lake Balaton in 2017. In addition, we tested the machine learning Gaussian process regression model, trained locally as a potential candidate to retrieve water quality parameters. We applied the automatic model selection algorithm to select the combination and number of spectral bands for the given water quality parameter to train the Gaussian Process Regression model. Lake Balaton represents different types of aquatic environments (eutrophic, mesotrophic and oligotrophic), hence being able to establish a model to monitor water quality by using S3 OLCI products might allow the generalization of the methodology.
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Bhandari, Dilliram. "Test of Learning Capability Model in Nepalese Commercial Banks." Dristikon: A Multidisciplinary Journal 10, no. 1 (December 31, 2020): 82–102. http://dx.doi.org/10.3126/dristikon.v10i1.34544.

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Learning and innovation are being threshold capabilities of modern organizations. Taking this into consideration, this study attempts to explore the learning orientation of organizational learning capability (OLC) and test a learning model in Nepalese commercial banks which have been operating in a highly competitive and volatile environment with strict regulatory frameworks. A descriptive research design has been followed to explore the state of OLC in Nepalese commercial banks. The population of this study comprised of all 27 commercial banks of Nepal and the sample frame for this study included 11 commercial banks, out of which, three were publicly-owned banks and eight were private sector banks. The informants of this study are the middle and top-level employees of the sample banks from both branch and corporate (head) offices. Altogether 415 questionnaires were distributed, out of these 265questionnaires were returned and finally, 245 responses were used for further analysis. Descriptive research design was followed to explore the state of OLC in Nepalese commercial banks. The development of the measurement model of OLC was achieved at two level sex placatory factor analysis (EFA) and confirmatory factor analysis (CFA). This study proposes leaning model for Nepalese commercial banks. This is expected to give the first insight into the items and constructs to build the learning capability model for enhanced organizational effectiveness. This study also showed that Nepalese commercial banks are in poor state of OLC that shows they not oriented towards learning for building their capabilities.
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Mosca, Luigi, Martina Gianecchini, and Diego Campagnolo. "Organizational life cycle models: a design perspective." Journal of Organization Design 10, no. 1 (January 20, 2021): 3–18. http://dx.doi.org/10.1186/s41469-021-00090-7.

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AbstractNew competitive and environmental challenges have fostered renewed attention towards organizational design. This scenario calls for a significant return to organizational design studies that embrace a holistic approach, especially those focusing on the simultaneous interaction of multiple design elements. Organizational life cycle (OLC) models provide a fitting response to this call. In this paper, we review the organizational design characteristics of five seminal OLC models. We show that according to these OLC models, growth in size—which is described as unavoidable—generates business issues that firms are forced to solve by adopting only one possible organizational configuration, here following a deterministic organizational approach. We challenge this approach and propose conceiving of OLC as an evolutionary process, which calls for a variety of equifinal organizational solutions. We conclude by proposing future research avenues.
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Khan, Samar Hayat, Abdul Majid, Muhammad Yasir, and Asad Javed. "Social capital and business model innovation in SMEs: do organizational learning capabilities and entrepreneurial orientation really matter?" European Journal of Innovation Management 24, no. 1 (December 18, 2020): 191–212. http://dx.doi.org/10.1108/ejim-04-2020-0143.

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PurposeThis research aims to concentrate on the important concern that how social capital (SC) influences business model innovation (BMI) in the course of the mediating role of organizational learning capabilities (OLC) and the moderating role of entrepreneurial orientation (EO). In the context of small and medium enterprises (SMEs), this study empirically tested a theoretical model of BMI to advocate a mechanism for the analysis of its significant determinants.Design/methodology/approachIn order to achieve the objective of the research, survey method was utilized, and data were collected from 521 CEOs, MDs and the owners of ICT sector SMEs. Correlation, causal step approach and regression analysis were used to test the proposed model.FindingsFinding of the research advocates that OLC mediate the relationship between SC and BMI. In addition, stronger EO augments the association between OLC and BMI.Practical implicationsThe study adds to the literature by providing insights regarding the impact of SC, OLC and EO on BMI of small firms.Originality/valueThis research enriches the existing knowledge by testing a mediating role of OLC between SC-BMI link and, therefore, makes an important addition to the existing knowledge in the context of SMEs by concentrating on the relationship between SC, OLC, BMI and EO.
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Karamperidou, Christina, Francesco Cioffi, and Upmanu Lall. "Surface Temperature Gradients as Diagnostic Indicators of Midlatitude Circulation Dynamics." Journal of Climate 25, no. 12 (June 15, 2012): 4154–71. http://dx.doi.org/10.1175/jcli-d-11-00067.1.

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Abstract Zonal and meridional surface temperature gradients are considered to be determinants of large-scale atmospheric circulation patterns. However, there has been limited investigation of these gradients as diagnostic aids. Here, the twentieth-century variability in the Northern Hemisphere equator-to-pole temperature gradient (EPG) and the ocean–land temperature contrast (OLC) is explored. A secular trend in decreasing EPG and OLC is noted. Decadal and interannual (ENSO-related) variations in the joint distribution of EPG and OLC are identified, hinting at multistable climate states that may be indigenous to the climate or due to changing boundary forcings. The NH circulation patterns for cases in the tails of the joint distribution of EPG and OLC are also seen to be different. Given this context, this paper extends past efforts to develop insights into jet stream dynamics using the Lorenz-1984 model, which is forced directly and only by EPG and OLC. The joint probability distribution of jet stream and eddy energy, conditional on EPG and OLC scenarios, is investigated. The scenarios correspond to (i) warmer versus colder climate conditions and (ii) polarized ENSO phases. The latter scenario involves the use of a heuristic ENSO model to drive the Lorenz-1984 model via a modulation of the EPG or the OLC. As with GCMs, the low-order model reveals that the response to El Niño forcing is not similar to an anthropogenic warming signature. The potential uses of EPG and OLC as macro-level indicators of climate change and variability and for comparing results across GCMs and observations are indicated.
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Dissertations / Theses on the topic "OLCO model"

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Lee, Hannah Yun Young. "Calcium homeostasis in lens transparency and the involmement of calpains in cataract." Lincoln University, 2006. http://hdl.handle.net/10182/1897.

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The absolute clarity of the lens of the eye is vital in the visual system. The unique structural and physiological properties of the lens are tightly integrated with highly ordered protein content to allow the lens to remain transparent. Consequently, any alteration or disturbance of these highly ordered proteins can affect the optical properties of the lens. In humans, cataracts are the major cause of blindness, yet the exact aetiology of cataract formation (cataractogenesis) is not fully understood. The purpose of the current research was to investigate whether deregulation of the Ca²⁺-dependent enzyme, calpains, following changes in lens Ca²⁺ homeostasis, is a key mechanism leading to undesired cleavage of a number of proteins that are linked with maintaining lens transparency and contributing to cataractogenesis. An ovine lens culture (in vitro) system and the heritable ovine cataract (in vivo) model were used to test the research hypothesis. The Ca²⁺ ionophore, ionomycin, was used to induce a Ca²⁺ overload and in vitro opacification during lens culture. Opacity in the lens was graded by a computer image analysis program. Protein profile (SDS-PAGE, 2-DE and Western detection), calpain activity (casein zymography), lens structure (microscopic view) and cytotoxicity level (LDH leakage assay) were analysed in Ca²⁺-induced opaque lenses. The involvement of calpain during opacification was further examined by applying synthetic exogenous calpain inhibitors to the in vitro system. Two novel exogenous calpain inhibitors were also assessed for their therapeutic potential in preventing the progression of cataracts in the in vivo cataract model by topical administration of the inhibitor direct to the sheep's eye over a 11 week period. HPLC was used to detect the penetration of these compounds into ocular tissues. Sustained Ca²⁺ influx into cultured lenses caused dense opacification. The opacity was characterised by formation of a turbid fraction and cell death in the outer cortex of the ovine lens. There was increased calpain autolysis associated with the progress of opacification, indicating increased calpain activity. Major degradation of the cytoskeletal proteins, spectrin and vimentin, was observed whilst there was limited degradation of the lens structural soluble proteins, crystallins, in response to a Ca²⁺ flux. Lens proteins were protected from degradation by adding synthetic calpain inhibitors to the culture medium. Topical administration of novel anti-calpain molecules failed to retard the progression of cataractogenesis in the ovine inherited cataract model. Further investigation of drug penetration showed that efficacy of inhibitory compounds was limited by permeability of these molecules across the cornea and the ability of the molecules to reach and penetrate into the lens. The ovine lens Ca²⁺-induced opacification (OLCO) model in this thesis has provided a model to understand the role of Ca²⁺ homeostasis in lens transparency. With sustained intracellular Ca²⁺ level, the degradation of cytoskeletal elements is highly correlated with calpain activity. Cataractogenesis is the pathological response to the loss of lens Ca²⁺ homeostasis in this model. The current results support the hypothesis that the deregulation of calpain activity is a trigger for a series of cascading events, leading to death of the cells in the lens.
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Baião, André Francês. "Simulador óptico dinâmico do olho humano." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/9751.

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Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica
Objectivo: Este trabalho teve como objectivo desenvolver um simulador óptico dinâmico do olho humano combinando as ferramentas Zemax (desenho óptico) e MATLAB (programação) e utilizando os estudos existentes sobre as variações dos diversos componentes com a idade e acomodação. Pretendeu-se que, ao introduzir no programa os parâmetros relevantes de um sujeito e situação de funcionamento do olho, e com base nestas, este altere os parâmetros do desenho óptico, de forma a poder-se analisar o comportamento óptico deste. Método: O simulador, a que se chamou dEYEnamic, baseou-se no modelo óptico de Dubbelman, dependente do nível de acomodação e idade. O modelo foi adaptado para contemplar a dispersão cromática no olho humano e devidamente testado. Seguidamente foi implementado na ferramenta desenvolvida que assegura a introdução dos dados e comunicação com o Zemax, através do protocolo de comunicação Microsoft Windows DDE, facilitada pelo conjunto de funções MZDDE. Resultados: O simulador foi testado com o olho em várias situações que permitiram a sua validação em termos de implementação do modelo óptico base, bem como em termos de customização do modelo ocular por parte do utilizador. Conclusões: Conclui-se que o simulador construído replica as condições de funcionamento do olho dito normal. O programa desenvolvido permite ainda que o utilizador modifique o modelo ocular como pretendido, possibilitando a customização do modelo. O facto de estar construído numa plataforma de traçado de raios não sequencial permite que no futuro possam ser contemplados e implementados parâmetros com vista a obtenção de um modelo virtual completo. O simulador apresenta um grande potencial de expansão na investigação da performance visual em função de várias fontes de luz.
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Paiva, Cíntia Sade de. "Olho seco agrava o desfecho da queimadura alcalina da córnea." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/17/17150/tde-07012016-091105/.

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Introdução: As queimaduras alcalinas da córnea fazem parte dos ferimentos mais devastadores para o olho. Objetivo: Os objetivos foram investigar o efeito aditivo do olho seco na atividade de proteases na superfície ocular e complicações corneanas apos lesão ocular alcalina e também investigar a eficácia da terapia anti-inflamatória controlar este processo. Métodos: Um modelo combinado (CM) de olho seco e queimadura alcalina unilateral foi usada. Resumidamente, camundongos C57BL /6 foram submetidos à queimadura alcalina unilateral (AB) com ou sem olho seco concomitante por 2 ou 5 dias. Um grupo separado de animais foram submetidos a ambos modelos (AB e olho seco) foram tratados topicamente com a Dexametasona, ou Doxiciclina ou colírio controle de solução salina balanceada (BSS). Os camundongos foram observados diariamente para verificar o aparecimento de perfuração da córnea. Córneas inteiras foram colhidas e homogeneizadas para extração de RNA. PCR quantitativo em tempo real foi realizada para medir a expressão de citocinas inflamatórias, metaloproteinases de matriz (MMP). Ativdade da MMP-9, atividade da gelatinase e da atividade da mieloperoxidase (MPO) foram avaliados em córneas homogeneizadas. A presença da infiltração de neutrófilos foi avaliada por imunohistoquímica e citometria de fluxo. Resultados: Os olhos submetidos ao modelo combinado de AB e olho seco (CM) tiveram 20% de taxa de perfuração estéril da córnea 1 dia após a lesão inicial; que aumentou para 35% em 5 dias. Houve um atraso no fechamento da ferida e aumento de opacidade residual da córnea. Aumento dos níveis de IL-1, IL-6, e as MMPs 1, -3, -8, -9, 13 e CXCL1, foram encontrados após 2 dias no CM comparando com córneas AB. Um aumento da imunorreatividade da MMP-1, -3, -9 e -13 e atividade gelatinolítica da MMP-9 foram observadas em comparação com córneas do grupo CM comparado com AB. O aumento da infiltração de neutrófilos e a atividade da mieloperoxidase foi observado no grupo CM comparando-se com córneas do grupo AB após dois dias da lesão inicial. Não foram observadas perfurações nas córneas tratadas com Dexametasona. Nos olhos tratados com Doxiciclina, 100% do fechamento da ferida pós-lesão no dia 2 e pontuação significantemente menor na escala de opacidade da córnea em relação ao BSS também foram observadas nos dias 4 e 5. Córneas tratadas com Dexametasona apresentaram a menor pontuação de opacidade da córnea. Tratamento com Dexametasona diminuiu significativamente os níveis de mRNA da IL-1, IL-6, e MMP-1, -9, -13, e o TIMP-1 depois de 2 dias, e aumentou os níveis de MMP-8, enquanto que o tratamento com Doxiciclina diminuiu significativamente IL-1, IL-6, MMP-8, -9 e, em comparação com córneas tratadas com BSS. A diminuição da imunorreatividade da MMP-1, -9 e -13 e atividade gelatinolítica foram vistos em córneas tratadas com Doxiciclina e Dexametasona em comparação com o veículo BSS. O aumento da infiltração de neutrófilos e a atividade da mieloperoxidase foi observado no grupo BSS comparação com o grupo Dexametasona 2 dias pós-lesão. Conclusões: O olho seco ambiental piora o resultado da queimadura ocular alcalina, criando uma tempestade de citocinas e proteases, aumentando o risco de perfuração corneana. Entretanto, o tratamento inicial com terapia anti-inflamatória é muito eficaz na preservação da transparência corneana e facilita a cicatrização de feridas, enquanto controla a produção de MMP e a migração de neutrófilos.
Introduction: Alkali burns to the cornea are among the most devastating injuries to the eye. Purpose: To evaluate the effects of dry eye on ocular surface protease activity and sight threatening corneal complications following ocular surface chemical injury and also to investigate the efficacy of anti-inflammatory therapy controlling this. Methods: A combined model (CM) of unilateral alkali burn and dry eye was used. Briefly, C57BL/6 mice were subjected to unilateral alkali burn (AB) with or without concomitant dry eye for 2 or 5 days. A separate group of mice subjected to both AB and dry eye were topically treated with Dexamethasone (Dex), Doxycycline (Doxy) or saline control (BSS). Mice were observed daily for appearance of corneal perforation. Whole corneas were harvested and lysed for RNA extraction. Quantitative real time PCR was performed to measure expression of inflammation cytokines, matrix metalloproteinases (MMP). MMP-9 activity, gelatinase activity and myeloperoxidase (MPO) activity were evaluated in corneal lysates. Presence of infiltrating neutrophils was evaluated by immunohistochemistry and flow cytometry. Results: Eyes subjected to the combined model of AB and dry eye (CM) had 20% sterile corneal perforation rate as soon as 1 day after the initial injury, which increased to 35% by 5 days, delayed wound closure and increased corneal opacity. Increased levels of IL- 1, IL-6, and MMPs 1,-3,-8,-9, 13, and CXCL1 transcripts were found after 2 days in CM compared to AB corneas. Increased MMP-1, -3,-9 and -13 immunoreactivity and gelatinolytic activity were seen in CM corneas compared to AB. Increased neutrophil infiltration and MPO activity was noted in the CM group compared to AB 2 days post injury. No perforations were observed in the Dex treated corneas. Doxy treated eyes had 100% of wound closure 2D post-injury, and significant lower corneal opacity scores at days 4 and 5 compared to BSS. Dex-treated corneas showed the lowest corneal opacity score. Dex treatment significantly decreased mRNA levels of IL-1, IL-6, and MMPs -1,-9, -13, and TIMP-1 after 2 days with increased levels of MMP-8, while Doxy treatment significantly decreased IL-1, IL-6, MMP-8, and -9, compared to BSS-treated corneas. Decreased MMPs -1,-9 and -13 immunoreactivity and gelatinolytic activity were seen in corneas treated with Doxy and Dex compared to BSS vehicle. Increased neutrophil infiltration and MPO activity was noted in the BSS group compared to Dex 2 D post-injury. Conclusions: Desiccating stress worsens outcome of ocular alkali burn, creating a cytokine and protease storm with greater neutrophil infiltration, increasing the risk of corneal perforation. However, early treatment with anti-inflammatory therapy is very efficacious in preserving corneal clarity and facilitating wound healing, while controlling MMP production and migration of neutrophils.
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Delgado, Esmeralda Sofia da Costa. "Estudo da regulação da circulação ocular num modelo de olho isolado de coelho." Doctoral thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2008. http://hdl.handle.net/10400.5/461.

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Dissertação de Doutoramento em Ciências Veterinárias
A circulação ocular compreende dois compartimentos: o retiniano possui receptores autonómicos e é autoregulado, enquanto que o coroideu possui inervação adrenérgica e existe controvérsia acerca da presença de autoregulação. Nesta tese criámos e optimizámos um modelo experimental de olho isolado de coelho para ajudar a clarificar os mecanismos de controlo locais da circulação ocular independentemente de outras interferências presentes num modelo in vivo. Surpreendentemente, antes da administração de qualquer fármaco, observámos respostas de vasomotricidade intrínseca em todos os modelos experimentais. Validámos o modelo utilizando fármacos adrenérgicos de efeitos conhecidos. A injecção de fenilefrina (α1-adrenérgico) desencadeou uma resposta vasoconstritora e diminuiu a frequência e aumentou a amplitude das oscilações enquanto que a prazozina (α1-bloqueador), a fentolamina (α1,2 -bloqueador) e o labetalol, (αβ-bloqueador) provocaram vasodilatação e diminuíram a intensidade das oscilações de vasomotricidade intrínseca. Analisámos as variações de pressão decorrentes da injecção intraarterial de outros neurotransmissores: a Endotelina-1, o L-NAME (antagonista do Óxido Nítrico) e o Neuropéptido Y induziram uma resposta vasoconstritora e aumento da frequência e amplitude das oscilações enquanto que a L-Arginina (precursor do Óxido Nítrico), o Péptido Vasointestinal e a amlodipina (bloqueador dos canais de cálcio) desencadearam os efeitos opostos. Estes resultados abrem novas perspectivas para a manipulação terapêutica das doenças oculares isquémicas como sejam a retinopatia diabética e o glaucoma
ABSTRACT: Ocular circulation has two compartments: the retina has autonomic receptors and is also autoregulated, while the choroid has adrenergic innervation but there is still some controversy about the presence of autoregulation. In the current investigation we developed an experimental model of isolated rabbit eye to help clarifying the local mechanisms of control of ocular circulation, independently of other interferences present in an “in vivo” model. Surprisingly, before any drug administration, we observed intrinsic vasomotricity in every animal model. We validated the model using adrenergic drugs of known effects. The injection of phenylefrine (α1-adrenergic) elicited vasoconstriction and decreased the frequency but increased the amplitude of the oscillations while prazozin (α1-blocker), phentolamine (α1,2 -blocker) and labetalol, (αβ-blocker) evoked vasodilation and a decrease in both the frequency and amplitude of the oscillations of intrinsic vasomotricity. We analysed the perfusion pressure changes following the intraarterial injection of other neurotransmitters: Endotelin-1, L-NAME (Nitric Oxide antagonist) and Neuropeptide Y elicited vasoconstrition and increased the frequency and amplitude of the oscillations while L-Arginine (Nitric Oxide precursor), Vasointestinal Peptide and amlodipine (calcium channel blocker) evoked the opposite effects. These results open new perspectives to the therapeutical handling of isquemic ocular diseases such as diabetic retinopathy and glaucoma
Trabalho realizado ao abrigo do Projecto de Investigação 71/Oftalmologia financiado pelo Centro de Investigação Interdisciplinar em Sanidade Animal da Faculdade de Medicina Veterinária de Lisboa.
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5

Xavier, Bruna Liana Mattiuzzi Frainer. "Constituição de modelo cinético baseado em agrupamentos químicos para o craqueamento térmico de biomassa triglicérica." reponame:Repositório Institucional da UFSC, 2017. https://repositorio.ufsc.br/xmlui/handle/123456789/183412.

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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2017.
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O craqueamento térmico é um processo onde ocorre a quebra das cadeias de hidrocarbonetos na ausência de oxigênio, com geração de uma quantidade expressiva de produtos de cadeia menor, alguns deles com características muito semelhantes ao diesel e à gasolina, por exemplo, quando a reação é conduzida em temperaturas na faixa de 500 °C e utilizando como matéria-prima os triacilglicerois. Neste trabalho foram realizados experimentos em um sistema reacional que opera em regime contínuo, com o intuito de propor modelos cinéticos para a reação de craqueamento térmico de óleo de soja, com base nos agrupamentos químicos presentes nos produtos. A constituição de modelos, levando-se em conta os balanços de massa do processo, assim como os mecanismos de reação envolvidos, possibilitaram uma melhor compreensão do processo e podem vir a contribuir para o aumento da eficiência e possível ampliação industrial. As propostas de mecanismos cinéticos feitas com agrupamentos de 6 lumps permitiram melhorar as regressões realizadas, bem como representar de maneira satisfatória as reações que ocorrem no craqueamento térmico, principalmente no que diz respeito ao consumo de biomassa. Os resultados obtidos com a mudança na geometria do reator, bem como a caracterização dos produtos e modelos cinéticos propostos evidenciam o potencial deste tipo de processo na obtenção de combustíveis renováveis provenientes de biomassa.
Abstract : Thermal cracking is the process of breaking the molecules of large hydrocarbons in the absence of oxygen, with the generation of an expressed amount of smaller chain products. Some compounds have very similar characteristics to biodiesel and biogas when the reaction is conducted at temperatures around 500 °C and using triacylglycerol as feedstock. This work was carried out in a continuous reaction system aiming on propose kinetic models for the thermal cracking of commercial soybean oil, based on the chemical groups present in the products. The constitution of models takes into account the mass balance of the process and the reaction mechanisms involved, allowing a better understanding of the process. Furthermore, it can contribute to increase reaction efficiency and a possible industrial expansion. A 6- lump kinetic mechanism proposed in this work allowed to improve the regressions performed, as well as representing satisfactorily the reactions that occur in the thermal cracking, mainly regarding to biomass consumption. The results obtained with the change in the reactor geometry, along with the characterization of the proposed kinetic products and models, showed the potential of this type of process in the production of renewable fuels from biomass.
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6

Castellar, Leonardo dos Santos. "Modelo de transplante de ilhotas pancreáticas para a câmara anterior do olho em camundongos diabéticos." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-12062015-161511/.

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Estima-se que, em 2013, cerca de 382 milhões de pessoas eram portadoras de diabetes mundialmente. Já o diabetes mellitus do tipo 1 (DMT1) representa de 5-10% desse total de casos, cujo tratamento atual se pauta na administração de insulina exógena. Contudo, desde a publicação do protocolo de Edmonton, o transplante de ilhotas pancreáticas se apresenta como nova técnica no tratamento para o DMT1, inclusive obtendo a independência de insulina em alguns casos. Apesar disso, a escolha do sítio receptor ainda é essencial para diminuir efeitos adversos e permitir o acompanhamento do enxerto. Nesse sentido, destaca-se o transplante de ilhotas para a câmara anterior do olho, pois permite, além do restabelecimento do controle glicêmico, o estudo da fisiologia dos enxertos in vivo. Dessa forma, o objetivo foi estabelecer metodologia de isolamento e transplante de ilhotas de alta reprodutibilidade e baixo custo, utilizando a câmara anterior do olho como sítio receptor. O isolamento foi realizado via injeção de solução de colagenase (1 mg/mL via ducto colédoco) em camundongos machos C57BL/6 hígidos de 8 semanas de idade e posterior transplante dessas ilhotas para camundongos machos da mesma espécie com diabetes induzido por injeção de aloxana (60 mg/kg, i.v.). Esses camundongos foram submetidos a infusão de aproximadamente 250 equivalentes de ilhotas (IEQs) para a câmara anterior do olho e tiveram sua glicemia e alteração de massa corpórea acompanhadas por 14 dias após o transplante. Também foi realizado teste de tolerância a glicose via injeção de solução de glicose (2g/kg i.p.) e realização da curva glicêmica. Obteve-se, na etapa de padronização, que a adição de 0,5% (%p/v) de albumina de soro bovino à solução de colagenase foi capaz de aumentar o número de IEQs isolados por animal. Quanto ao transplante, obteve-se que 50% dos animais submetidos à técnica tiveram diminuição significativa na sua glicemia (172,5 ± 6,4 mg/dL), quando comparados com o grupo controle diabético (582,8 ± 27,5 mg/dL) (p < 0,05). Entretanto, todos os animais tiveram aumento significativo da massa corpórea no período de acompanhamento e glicemia de jejum significativamente menor que os animais diabéticos (p < 0,05). Ademais, a curva glicêmica dos animais que tiveram transplante considerado bem sucedido, no teste de tolerância a glicose, se aproxima da curva do grupo controle sadio. Conclui-se que o modelo de transplante de ilhotas pancreáticas para a câmara anterior do olho foi bem estabelecido neste projeto, confirmado pelos resultados que evidenciam o transplante de ilhotas funcionais capazes de reduzir sensivelmente a glicemia e promover o ganho de peso em camundongos diabéticos.
It is estimated that, in 2013, around 382 million people had diabetes worldwide. Of that number, 5-10% represented cases of T1DM, which treatment is based in the administration of exogenous insulin. However, since the Edmonton protocol was published, islet transplantation presented itself as novel technique for T1DM treatment, achieving insulin independence in some cases. Although, recipient site choice is still essential to diminish side effects and enable graft follow up. In that sense, transplantation to the anterior chamber of the eye stands out, since it allows, beyond the reestablishment of glycemic control, study of islet physiology in vivo. That way, the objective was to establish a low cost and high reproducible model of islet isolation and transplantation, using the anterior chamber of the eye as receptor site. Islet isolation was made by injection of collagenase solution (1 mg/mL via common bile duct) in 8 week old healthy male C57BL/6 mice and followed by transplantation of these islets to male mice of the same age and species with diabetes induced by alloxan injection (60 mg/kg i.v.). These mice were subject of 250 islet equivalents (IEQs) infusion to the anterior chamber of the eye and had their blood glucose and change in body mass monitored for 14 days after transplantation. A glucose tolerance test (GTT) was also made, by injection of glucose solution (2g/kg i.p.) and a glycemic curve was plotted. In the standardization period, was observed that the addition of 0,5% (%w/v) bovine serum albumin is capable of increasing the number of IEQs isolated from each animal. About the transplants, was obtained that 50% of animals subject to transplantation had their blood glucose decreased significantly (172,5 ± 6,4 mg/dL), when compared to the diabetic control group (582,8 ± 27,5 mg/dL) (p < 0,05). However, all animals subject to the procedure had significant body mass increase, when compared to the same control group and fasting blood glucose significantly lower than diabetic animals (p < 0,05). Moreover, the glycemic curve of animals, who had their transplantation considered successful, was similar to that found in healthy control animals, in the GTT. We conclude that the model of transplant to the anterior chamber of the eye is well established in this project, which is confirmed by results that shows transplantation of functional islets, capable of promoting a significant decrease in blood glucose and an increase in total body mass in diabetic animals.
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Custodio, Aline Ferrão. "Modelagem e simulação do processo de separação de oleo de soja-hexano por evaporação." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266512.

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Orientadores: Rubens Maciel Filho, Dailton de Freitas Rezende
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
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Resumo: Até as duas primeiras décadas do século XX, a extração industrial de oleaginosas se fazia, exclusivamente pelo uso de prensas. As prensas, embora extraíssem um óleo de muito boa qualidade, deixavam resíduos no material sólido (torta) superiores, por exemplo a 5% para grãos como o de soja. Tais resíduos além de implicarem em perda de óleo, afetavam a qualidade da torta, que é também um dos produtos efluentes do extrator. A extração por solvente, por outro lado, é capaz de retirar o óleo, deixando resíduos inferiores a 1%. Após a extração, os sólidos são encaminhados ao dessolventizador e a micela (mistura óleo-solvente) ao sistema de destilação, composto por dois evaporadores em série e uma coluna de dessorção (stripping). A unidade de evaporação é uma das que mais demandam energia em uma planta de processamento. Assim, a modelagem matemática dinâmica deste processo com vistas à otimização do consumo energético e à avaliação do desempenho de políticas de controle torna-se um requisito decisivo para operação economicamente viável. O objetivo geral deste trabalho é desenvolver um modelo dinâmico efetuando análises de sensibilidade paramétrica para um evaporador típico da indústria de extração de óleos vegetais, visando a otimização deste processo, ou seja, a recuperação máxima de solvente e o consumo mínimo de energia. A fim de analisar as condições de operação do sistema, propôs-se um modelo matemático do sistema de evaporação com base no de TONELLI et al. (1990), consistindo em balanços mássicos global e de óleo e de balanço energético em torno do sistema de evaporação. O programa simulador foi construído em linguagem FORTRAN. Este programa, a partir de informações tais como temperatura, pressão e concentração de alimentação, assim como de quais são os componentes envolvidos, calcula propriedades termodinâmicas tais como temperaturas de ebulição, capacidades térmicas e entalpias de misturas. Desse modo, um mínimo de informações são requeridas, permitindo simulações rápidas do processo de evaporação. O programa computacional elaborado permitiu simulações rápidas e com baixos erros numéricos para o processo de evaporação do solvente em uma unidade de dessolventização do óleo após extração convencional. Este programa permitiu ainda avaliações de efeitos para os fatores influentes na evaporação. Considerando-se a intensidade das perturbações realizadas e o nível central dos fatores, o fator fração mássica de óleo na entrada foi o que apresentou o maior efeito. Já a velocidade de escoamento do vapor de água de aquecimento foi o fator com o menor efeito no teor de óleo da micela efluente
Abstract: Until the two first decades of century XX, the industrial extraction of oleaginosas were carried out exclusively by mechanical process. This process allow to extracted oil of very good quality, but it leads the left residues in the solid material (pie) to be very high, for example 5% for grains as of soy. Such residues besides implying in loss of oil, affected the quality of the pie, that is also one of the effluent products of the extractor. The extraction for solvent, on the other hand, is capable to remove the oil, leaving residues to be smaller (1%). After the extraction, the solids are directed to the dessolventizador and miscella (oil-solvent mixture) to the distillation system. Witch is composed by two evaporators in series and a stripping column. The unit of evaporation is one that demands for high energy consumption in a processing plant. Thus, the dynamic mathematical modeling of this process with sights to the reduction of the energy consumption and to the evaluation of the performance of control politics becomes a decisive requirement for economically viable operation. The general objective of this work is to develop a dynamic model of the process witch allow for parametric sensitivity analyze for a typical evaporator for the vegetal oil industry extraction. The aim is to have a tool for either process optimization or maximum recovery of solvent. The deterministic mathematical model is developed through mass and energy balance equation together with heat and mass transfer parameter correlations. The simulator was build up in FORTRAN. The software uses operational information as feed temperature, concentration and pressure witch allows for the calculation of the thermodynamic properties such as thermal temperatures of boiling, capacities and enthalpies of mixtures. In this way, a minimum of information is required, allowing fast simulations of the evaporation process. Through experimental design procedure applied to the deterministic model was possible to identify the main operational variables effects as well as the impact of the extraction array variables has on the process behaviors. The mass oil fraction in the feed was found to have the largest effect. The speed of the water vapor draining for the heating zone was the factor with the loweit effect in the oil miscella effluent
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Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
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8

Bordin, Vivian Gomes Deolindo. "Modelo computacional da córnea e do humor aquoso." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18133/tde-09052017-152424/.

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A pressão intra-ocular (PO) é um importante parâmetro na avaliação da saúde ocular, sendo que o diagnóstico e a monitorização do glaucoma dependem de sua adequada mensuração. Entretanto estudos recentes mostram uma redução na PO medida através de tonômetros de aplanação após a cirurgia, o que provavelmente, é provocado por alterações da forma, estrutura e espessura da córnea em decorrência de procedimento cirúrgico freqüente no tratamento da miopia. A medida da PO é realizada aplicando uma pressão externa sobre o centro da córnea até que essa esteja totalmente plana. A deformação provocada pela pressão externa depende não somente da pressão intra-ocular mas também da energia de interação entre as moléculas da córnea, entre as moléculas do humor aquoso assim como, da interação mútua entre as moléculas do humor aquoso e da córnea. A quantidade e o tamanho das moléculas que formam estas estruturas (humor aquoso e córnea) também influenciam a deformação. Portanto, propomos neste trabalho, um modelo computacional que permite representar as moléculas da córnea e do humor aquoso com suas devidas espessuras e arranjos em função das energias de interação. O trabalho foi desenvolvido utilizando o programa DICE, o qual tem a finalidade de simular sistemas moleculares densos, compostos por diferentes tipos de partículas interagindo através de uma função (U) que descreve como a energia potencial de interação varia com a distância entre elas. Após diversas modificações dos parâmetros iniciais verificamos a tendência para o equilíbrio do sistema provando que o modelo é viável e factível de ser aplicado a avaliação da PO.
Intraocular pressure is an important parameter in the evaluation of eye health so that the diagnosing and monitoring of glaucoma depend on their correct measuring. However recent studies show a reduction in intraocular pressure measured by means of plaining tonometers after surgery, what is probably caused by alterations in the form, structure and thickness of the cornea as a result of the surgical procedure frequent in treatment of miopy. Intraoculoar pressure is measured by applying an external pressure on the center of the cornea until it is completely plain (flat). The deformation caused by external pressure depends not only on intraocular pressure but also on the interaction force among the molecules of the cornea, among the molecules of the aqueous humour and also on the mutual interaction among the molecules of the aqueous humour and those of the cornea. The quantity and size of the molecules that make up these structures (aqueous humour and cornea) have an influence on the deformation as well. So, we propose in this work a computational model that allows to represent the molecules of the cornea and aqueous humour with their respective thickness and arrangements in relation to the interaction forces. The work has been developed with the program DICE, whose objective is to simulate dense molecular systems, composed by different types of particles interacting by means of a function (U) that describes how the potential interaction force varies according to thedistance between them. After various modifications of the initial parameters we verified the tendency to the balance of the system, proving that the model is viable and feasible of being applied in evaluation of intraocular pressure.
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Andrade, Alexey Santos de. "Avaliação do estresse oxidativo em modelo experimental de olho seco e a resposta ao uso de antioxidantes ômega 3 e ácido lipoico." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/84949.

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O filme lacrimal é o principal mecanismo de proteção da superfície ocular contra agentes externos e a quebra de sua homeostase pode levar à síndrome do olho seco, causando desde desconforto leve a dano severo na superfície ocular com prejuízo irreversível para a visão. A produção de lágrima pela glândula lacrimal está intimamente relacionada a fatores neuroendócrinos, hormonais e imunológicos e o estresse oxidativo pode ter um papel importante na sua regulação. Induzimos, neste estudo, o olho seco em modelo animal por supressão hormonal e realizamos a suplementação dietética com ácidos graxos poli-insaturados ômega 3 (AGPI n-3) e ácido lipoico, objetivando avaliar o estresse oxidativo e a resposta antioxidante na superfície ocular e glândula lacrimal e o papel destas substâncias no tratamento do olho seco. A produção lacrimal, medida através do teste de Schirmer, mostrou recuperação com a suplementação dietética com ácidos graxos poli-insaturados ômega 3 e ácido lipoico. O estresse oxidativo foi levemente modificado pelo ômega 3, enquanto o ácido lipoico teve um efeito pró-oxidante e antioxidante sítio específico, com influência importante na preservação da integridade da superfície ocular e melhora do olho seco. O dano oxidativo em proteínas foi medido através da quantificação dos níveis de carbonil e a peroxidação lipídica pela formação de MDA, defesas antioxidantes enzimáticas através da atividade da SOD total e GPx, defesas não enzimáticas através dos níveis de vitamina C, glutationa total e medida indireta de óxido nítrico. De acordo com nossos achados, o estresse oxidativo na glândula lacrimal não tem um papel importante no desenvolvimento do olho seco através de espécies reativas de oxigênio, mas o ácido lipoico altera o metabolismo de espécies reativas de nitrogênio e de vias de sinalização na superfície ocular ocasionando um aumento na atividade da peroxidase lacrimal e melhora da produção de lágrima com recuperação do teste de Schirmer.
The tear film is a major mechanism of ocular surface protection against harmful external agents and the breaking of its balance can lead to dry eye syndrome, causing from mild eye discomfort to scarring damage of the ocular surface with irreversible prejudice to vision. The production of tears by the lacrimal gland is closely related to neuroendocrine, hormonal and immunological factors and the oxidative stress can play an important role in its regulation. In this study, the dry eye was induced in an animal model by hormone suppression and the diet supplemented with omega 3 polyunsaturated fatty acids (PUFA) and alpha-lipoic acid for evaluation of oxidative stress and antioxidant response in the ocular surface and lacrimal gland and the role of these substances in the treatment of dry eye. The lacrimal production, measured by the Schirmer test, showed recuperation when diet was supplemented with omega 3 polyunsaturated fatty acids and alpha-lipoic acid. PUFA omega 3 seems to have little oxidative stress effect while alpha-lipoic acid has site-specific pro-oxidant and antioxidant effect with important influence in ocular surface integrity preservation and dry eye improvement. Oxidative damage in protein was measured by carbonyl levels and lipids peroxidation by MDA production, enzymatic antioxidant defenses by tSOD and GPx activity, non-enzymatic defenses by vitamin C, glutathione and indirect oxide nitric levels. It appears that oxidative stress in the lacrimal gland does not play an important role in the dry eye through reactive oxygen species, but alpha-lipoic acid alters the metabolism of reactive nitrogen species and signaling pathways on the ocular surface with increased activity of lacrimal peroxidase and improved in Schirmer test and lacrimal production.
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Fernandes, Marcio Rodolfo. "Um metodo streamline diffusion descontinuo aplicado a um modelo de espalhamento de manchas de petroleo." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307419.

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Orientadores: Jose Luiz Boldrini, Petronio Pulino
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Doutorado
Doutor em Matemática Aplicada
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Books on the topic "OLCO model"

1

Clark, Archie B. An investigation of classical dynamic scaling techniques applied to an oleo-pneumatic landing gear strut. Wright-Patterson Air Force Base, Ohio: Flight Dynamics, Air Force Wright Aeronautical Laboratories, Air Force Systems Command, 1987.

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Cunha, Marcelo Antonio da. No olho da rua: A vida na Fazenda Modelo, um dos maiores abrigos de mendigos do mundo. Rio de Janeiro, RJ, Brasil: Editora Nova Fronteira, 2008.

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No olho da rua: A vida na Fazenda Modelo, um dos maiores abrigos de mendigos do mundo. Rio de Janeiro, RJ, Brasil: Editora Nova Fronteira, 2008.

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Book chapters on the topic "OLCO model"

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Duraiappah, Anantha Kumar. "Issues in Production, Recycling and International Trade: Analyzing the Plastic Sector Using an Optimal Life Cycle (OLC) Model." In Computational Models in the Economics of Environment and Development, 51–106. Dordrecht: Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-007-0960-7_4.

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Kedar, Alexandre, Ahmad Amara, and Oren Yiftachel. "The Land Regime of the Late Ottoman Period." In Emptied Lands. Stanford University Press, 2018. http://dx.doi.org/10.11126/stanford/9781503603585.003.0003.

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This chapter begins to set the historical background for the book by outlining in detail the state of affairs in the Negev during the last period of Ottomans rule in the late nineteenth and early twentieth centuries. Focusing on tribal-state relations, the chapter explores the late Ottoman modes of governance, and traces changing Ottoman policies and practices in the region. More specifically, the chapter addresses the founding of the Beersheba sub-district, and seeks to understand the land regime that existed prior, during and after the Ottoman reforms (Tanzimat), especially the introduction of the 1858 Ottoman Land Code (OLC).
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"scto th ara ti rsetc ic te s d ( M mo OdSe ) l . f S or m ec it ahstadnad ta are called model output 1994). The state of ENSO is only one of many factors obs terevveedn SS gi T v en a perfect SRSoTp el feow re sckais ( t 1 -9 9i7 .e ) ., shtohweu (K se r d is hn to aKfuom re acrae st t al t . h1e99I5n ) d . ian summer monsoon m to oid ts elEuNsS ed O -a r t -N t C he E P cu rrent operational atmospheric Ward et al. (1993) discuss the useful level of skill In their study e , la ftoerd ty r -a fi i need vne fa lylspastu te brsn ta snfto ia rlpa ra d c ju ti sctamleun se ts . m of a d tr eop in ic a re l al n o ti r m th e A by f ri tchaenU fo KreM ca e st tse or th ol aotgihcaavleOb ff eiecnee (h xianm dc in aesd ts ) fo bra se th d e on specif e ie a d rs ( oofbsseeravseodn ) alSS fo Trew ca esrtess re in la ctei on 1s9h8i6p . swTih th esgeloabrael ly ladrigsetlry ib ubtaesdedSSoTn , SS st Tatiin st itchaelm ea o ch d el sism imulation wapserrieopde at 1e9d50 th -i 9r4 te . enEa ti cmh es s , e w as hoenraelpSoonue th n t. A O tla vnetrict , hean la dstade re claad ti e v , eltyhesm re aalll -ti EmNeSfOo re ccoam sts ­ u initial co unldaitt io io nnswatso st easrttiemdatwe ith th e s lig mha tl gynid tu if dfee ren otfvhaalviedah te addahisnkdic ll asstismim lar adteotwhiatthotbhtea in seadme fr osm ta t c is rto ic sasl -v av anrp ia re ti doincs ta ble and therefore random atmospheric methods. The chief limitation to further progress is a rai enrfaag ll edf or tion th ca elcm ul oad te e l. thTehebtehsitr te meondseilmeus la ti t m io antseao re flsaecaksoonf ( gJluonbeal th tr roopu ic gahlSSeSpTtefm or beecra ) s . tsAvcaclu id ra f te orfo th re ecawse ts ttgylpoibcaall ly v , a a ri l th ea ocuhghgitvheen seasonal SST pattern. Quite of ENSO would help, but would in most years be well, it sho at w io ends in sem as oodneall re ra piln ic fa altledpa th tt eeronbs se qruvietdeifn al sluffo fi rceiceanst. tsAatrmeoaslp so heu ri scedd , ynbaumtitchaely -m oondleyl -h baavseedusreaf in ul ­ T re hgu io s ns fo rofptrheec ip w it s a ystematic or tlido , n -t rhee la tmesdpaa ti pap ll l y ic var odel pre a d ti i o ct nys in g in biases. skill with lead times of a month or less before the require some kind ions wmoaun ld y r th ai antf al hlusm ea asnoin ty ( Fhoa ll sanidncerteaals . ed1 99 th 1 e ). Istuisscaelpsto ib p il o it s y si b o le f g ki ennderoaf te bdi as byadajuM stm OS ofteacdhjnuisqtumee . n T ts h , e perhaps those tropical west Africa to drought through the pro­ production of operat einot places a huge bnue rd ed en foorntthhiesg co re vsesrivoevreerdu re c c ti eonntd in ecnaedaers -. coTahsitsalcw ha e n st geAfirn ic a th nefolraensdtM because each time the m na oldd el y n is a m ch ic aanlge fo d r , eacansetwmsoedteo ls f s (e u . r g fa ., ceElb ta ohuinrdaan ry dhGaosnbgee1n99s6 ho ) w to nhbayve se v th e e ra lpo au te tnhtoirasla ne O ed S e statistics must be calculated to provide the to weaken the north African monsoon. More studies nneacleys si d sa s ad ojfu ry Msm tm u e lt n id ts e . c T ad h a is l re en qu se ir m es bltehsetgoe ne orbatta io in natnhdetorfopp ic oasls ib nloer th re g A io fr n ic aalnarnatihnrfo al p l, ogaesniwce ll inafs lu efnocr es on fundamental OiSmp st rao ti vse ti m cs enatnsdtuond th eerssecom re osdtehles , nseuecdh fo as r reg W ion ar sdwe it thaml. a ( r 1 gi 9n9a3l ) seaalssoonadlisrcau in sfsaltlh , e a re sk n il eleo de odt . her tahboosvee . related to the flux adjustments, discussed m tim ad eefboy re c th a e st sff real­ UK orM th et eeon ro olro th g e ic aasltOBfrfaizcielsw in ectes1e9 as 8o7n . dro Kungohwt le p d re gdeico ti fonEsNS in O m is a n in ysup ff airctisenotffotrher eg w io o n rl adlT se hviesreisa relatively dry area, subject to intermittent lbeescsaium se p o in rt a th n ese regions its influence is either small or Hastenr dartohuagnhdt. c T ol hleasbeorfao to re rs c a ( set . s g , ., asHw as etlelnarsatthho1s9e95b ) y , p ea ro st foBurnad zil an t than other factors. For instance, north­ are mainly statistical, although real-time dynamical patterns ( lFyo ll iandf lu west A nd eentcael. d frican w 19 b9y1 , H tro ept ic saela so Ant la ra nitn ic fa ll astenrath 1995, WSaSrTeM for eetceaosrtosl og hiacvae ard based on tropi lcbaOlAfefe ic n e . mTahdee st saitn is ctei cal 19f9o4 re ca bsy ts tahreeS1S9T 97 ) i . n In th aeddtirtoipoinc , aplaIrn ts d i of the Sahel are affected by on ENSO SSTs. On tl aanv ti ecraSgSeT , t a ro npoim ca allyAp tl aatn te ti rcnsSaSnTdsF Si o m ll i a la nrd ly , eltocaall . SS 19 T9p1a , tt Bar anns to Onceaannd (P Sam lm ith er11999866 ). , h re agvieonaboofuSt ou tw th ic Aem th e e ri cian , fl aule th nocue gh ofexEtN re SmOeE fo NrStOhs is , A no urstth ra w li eas , tnooftA ab ulsyt ra ilniatih er e ns influence precipitation in such as that in 1982-3, can dominate the circulation Drosdowsky 1993, F n re d th IendA ia uns tr O al c ia enanw north and and precipitation patterns over tropical South ericksen and i B nt aelrgo ( v e. ign . d , A sis m te e n ri t c ly a . h T ig hhe le r v ea el l -t o im f e sk iflol, resc im as itlsarhtaovethhaatdobatac in oend ­." In Droughts, 63. Routledge, 2016. http://dx.doi.org/10.4324/9781315830896-43.

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Conference papers on the topic "OLCO model"

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Gabet, R., E. Le Cren, C. Jin, M. Gadonna, B. Ung, Y. Jaouen, M. Thual, and S. LaRochelle. "Characterization of few mode fibers by OLCI technique." In 2014 European Conference on Optical Communication (ECOC). IEEE, 2014. http://dx.doi.org/10.1109/ecoc.2014.6963921.

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Hamel, Philippe, Yves Jaouen, Renaud Gabet, and Siddharth Ramachandran. "Chromatic dispersion measurements of few-mode fibres using OLCR technique." In 2006 32nd European Conference on Optical Communications - (ECOC 2006). IEEE, 2006. http://dx.doi.org/10.1109/ecoc.2006.4800945.

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Jaouen, Y., C. Palavicini, A. F. Obaton, C. Moreau, and P. Sillard. "Direct chromatic dispersion determination of higher-order mode fibers using OLCR technique." In 2005 Conference on Lasers and Electro-Optics (CLEO). IEEE, 2005. http://dx.doi.org/10.1109/cleo.2005.202197.

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Nofrion, Nofrion, Rahmanelli Rahmanelli, Yurni Suasti, Khairani Khairani, Bayu Wijayanto, Bigharta Bekti Susetyo, Rery Novio, and Surtani Surtani. "EXO OLO TASK Learning Model: What Should Students Do in The Class?" In International Conference on Education, Social Sciences and Humanities. Jakarta: RedWhite Press, 2019. http://dx.doi.org/10.32698/hum0216.

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Bittencourt, Marco, and Gabriela Ramos Correa. "ANÁLISE DE IMPACTO DE BALAS DE BORRACHA EM UM MODELO COMPUTACIONAL DO OLHO HUMANO." In XXIII Congresso de Iniciação Científica da Unicamp. Campinas - SP, Brazil: Galoá, 2015. http://dx.doi.org/10.19146/pibic-2015-37293.

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Ramos Correa, Gabriela, and Marco Bittencourt. "Análise de impacto de balas de borracha em um modelo computacional de olho humano." In XXIV Congresso de Iniciação Científica da UNICAMP - 2016. Campinas - SP, Brazil: Galoa, 2016. http://dx.doi.org/10.19146/pibic-2016-52026.

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Willich, Felix, Carsten Wolff, Andreas Sutorma, Uwe Jahn, and Merlin Stampa. "Model-based Systems Engineering of an Active, Oleo-Pneumatic Damper for a CS-23 General Aviation Aircraft Landing Gear." In 2021 IEEE European Technology and Engineering Management Summit (E-TEMS). IEEE, 2021. http://dx.doi.org/10.1109/e-tems51171.2021.9524897.

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Moura, Luiza Rosa de, Alessandra Martins Coelho, and Matheus de Freitas Oliveira Baffa. "Detecção Automática de Anomalias Oculares Utilizando Redes Neurais Convolucionais." In Encontro Nacional de Computação dos Institutos Federais. Sociedade Brasileira de Computação, 2021. http://dx.doi.org/10.5753/encompif.2021.15953.

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Analisando a importância do cuidado com a visão, o trabalho proposto tem como objetivo desenvolver um método de auxílio ao diagnostico de diferentes anomalias que acometem a região externa do olho. A Rede Neural Convolucional foi então utilizada para detectar padroes visuais das imagens da base de dados Warsaw BioBase Disease Iris v2.1, que posteriormente foram classificadas entre doentes e saudáveis. O classificador construído foi avaliado seguindo o protocolo de experimentação Holdout, obtendo uma taxa de acerto de 94%. Mediante tal resultado, é possível concluir que o modelo desenvolvido tem potencial para se tornar uma ferramenta para o auxílio ao diagnostico.
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Kim, Tae-Uk, Sung Joon Kim, and Seunggyu Lee. "Crashworthy Landing Gear Design Using a Composite Tube by Extra Energy Absorber." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36452.

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Landing gear is the one of the key components for improving aircraft crashworthiness because its primary function is the energy absorption. But, in general, the shock absorbers are designed to have best efficiency for normal landing cases and can be ineffective when faced with very high sink speed. Thus special design and implementation are necessary for landing gear to have crashworthiness. For this purpose, various concepts have been studied and put to practical use such as structural pin, pressure relief valve and additional energy absorbing devices, etc. In this paper, the composite tube is investigated as an extra energy absorber and adopted to landing gear to increase shock absorbing performance in case of crash. To do this, first the quasi-static and impact test of composite tubes are conducted and the analysis model is tuned to explain the test results. During the correlation process, the failure modes and the specific energy absorption of the composite tubes are analyzed and the optimal configurations are searched. The overall performance of landing gear including the composite tube is analyzed by developing a simplified dynamic model. Each force-stroke relation of oleo-pneumatic shock absorber, tire and composite tube are modeled as spring and damper, then the equation of motion is solved to obtain the crash responses. In this model, after the bottoming of shock absorber, the crushing of composite tube is activated for additional energy absorption. Numerical solutions show that the enhanced shock absorbing capability in case of crash when the composite tube adopted. For practical use, the landing gear performance should be verified by drop tests and this is author’s future research project.
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Reports on the topic "OLCO model"

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Beachkofski, Brian K. Elementary Model of Nose Gear Retraction and Oleo-Pneumatic Strut Compression. Fort Belvoir, VA: Defense Technical Information Center, August 1999. http://dx.doi.org/10.21236/ada374308.

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