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In order to realize in situ multi-frame framing, this paper designed and developed a large-waist framing converter tube. The size ratio between the waist and the object was about 1.16:1. The subsequent test results showed that the static spatial resolution of the tube could reach 10 lp/mm (@ 72.5%) under the premise of this adjustment, and the transverse magnification could reach 2.9. Once the MCP (Micro Channel Plate) traveling wave gating unit is equipped at the output end, it is expected to promote the further development of in situ multi-frame framing technology.
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The development of inertial confinement fusion (ICF) experiments necessitates the diagnostic instrument to have multiple frames with a high spatial and temporal resolution for the two-dimensional detection of the hot spot at the implosion end of the ICF. The existing sampling two-dimensional imaging technology in the world has superior performance; however, its subsequent development requires a streak tube with large lateral magnification. In this work, an electron beam separation device was designed and developed for the first time. The device can be used without changing the structure of the streak tube. It can be combined directly with the corresponding device and matched with a special control circuit. Based on the original transverse magnification, 1.77 times the secondary amplification can be achieved, which is conducive to expanding the recording range of the technology. The experimental results showed that the static spatial resolution of the streak tube after the inclusion of the device can still reach 10 lp/mm.
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For an electron-optical imaging system with wide beam focusing, the calculation of the field curvature can be performed only theoretically and requires the specific analytical expressions of the axial potential distribution in the streak tube and its corresponding derivatives, making the calculation cumbersome. Even when the electron trajectory is tracked using the numerical calculation method, the calculated results cannot be verified experimentally. A method for measuring the field curvature of the streak tube based on the spherical fluorescent screen is proposed for the first time, to the best of our knowledge. This method can directly measure the field curvature from the experimental image without requiring information on the internal structure of the streak tube, which is extremely useful for the design of the subsequent image reconstruction algorithm.
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Monitoring plant nitrogen (N) in a timely way and accurately is critical for precision fertilization. The imaging technology based on visible light is relatively inexpensive and ubiquitous, and open-source analysis tools have proliferated. In this study, texture- and geometry-related phenotyping combined with color properties were investigated for their potential use in evaluating N in pakchoi (Brassica campestris ssp. chinensis L.). Potted pakchoi treated with four levels of N were cultivated in a greenhouse. Their top-view images were acquired using a camera at six growth stages. The corresponding plant N concentration was determined destructively. The quantitative relationships between the nitrogen nutrition index (NNI) and the image-based phenotyping features were established using the following algorithms: random forest (RF), support vector regression (SVR), and neural network (NN). The results showed the full model based on the color, texture, and geometry-related features outperforms the model based on only the color-related feature in predicting the NNI. The RF full model exhibited the most robust performance in both the seedling and harvest stages, reaching prediction accuracies of 0.823 and 0.943, respectively. The high prediction accuracy of the model allows for a low-cost, non-destructive monitoring of N in the field of precision crop management.
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Brassica/química , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Nitrogênio/análise , Algoritmos , Biomassa , Modelos Teóricos , Avaliação Nutricional , FenótipoRESUMO
Macrophages under the conjunctival tissue are the first line defender cells of the corneas. Elimination of these cells would lead to aggravation of fungal keratitis. To determine how the course of fungal keratitis would be altered after the activation of these macrophages, a murine model was achieved by intrastromal instillation of latex beads before the corneas were infected with Fusarium solani. The keratitis was observed and clinically scored daily. Infected corneas were homogenized for colony counts. The levels of the IL-12, IL-4, MPO, MIF and iNOS cytokines were measured in the corneas using real-time polymerase chain reactions and enzyme-linked immunosorbent assays. CD3+, CD4+ and CD8+ lymphocytes in the corneas, submaxillary lymph nodes and peripheral blood were detected using immunohistochemistry and flow cytometry, respectively. The latex bead-treated mice exhibited aggravated keratitis. Substantially increased macrophage and polymorphonuclear leukocyte infiltration was detected in the corneas, although few colonies were observed. There was a marked increase in the IL-12, IL-4, MPO, MIF and iNOS expression in the corneas. The numbers of CD3+, CD4+ and CD8+ lymphocytes and the CD4+/CD8+ ratio were significantly enhanced in the corneas and submaxillary lymph nodes. However, the number of CD4+ lymphocytes was decreased in the peripheral blood, while the number of CD8+ lymphocytes increased. Collectively, our data demonstrate that the activation of macrophages in the cornea may cause an excessive immune response. Macrophages appear to play a critical role in regulating the immune response to corneal infections with F. solani.
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Infecções Oculares Fúngicas/imunologia , Fusariose/imunologia , Fusarium/isolamento & purificação , Imunidade Celular , Ceratite/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Animais , Córnea/imunologia , Córnea/patologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Infecções Oculares Fúngicas/microbiologia , Infecções Oculares Fúngicas/patologia , Feminino , Citometria de Fluxo , Fusariose/microbiologia , Fusariose/patologia , Imuno-Histoquímica , Ceratite/microbiologia , Ceratite/patologia , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , RNA/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The exposure of fruit surfaces to direct sunlight during the summer months can result in sunburn damage. Losses due to sunburn damage are a major economic problem when marketing fresh apples. The objective of this study was to develop and validate a model for simulating fruit surface temperature (FST) dynamics based on energy balance and measured weather data. A series of weather data (air temperature, humidity, solar radiation, and wind speed) was recorded for seven hours between 11:00-18:00 for two months at fifteen minute intervals. To validate the model, the FSTs of "Fuji" apples were monitored using an infrared camera in a natural orchard environment. The FST dynamics were measured using a series of thermal images. For the apples that were completely exposed to the sun, the RMSE of the model for estimating FST was less than 2.0 °C. A sensitivity analysis of the emissivity of the apple surface and the conductance of the fruit surface to water vapour showed that accurate estimations of the apple surface emissivity were important for the model. The validation results showed that the model was capable of accurately describing the thermal performances of apples under different solar radiation intensities. Thus, this model could be used to more accurately estimate the FST relative to estimates that only consider the air temperature. In addition, this model provides useful information for sunburn protection management.
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Exposição Ambiental , Monitoramento Ambiental/métodos , Frutas/fisiologia , Malus/fisiologia , Modelos Biológicos , Temperatura , Termografia/métodos , Simulação por Computador , Umidade , Estações do Ano , Tempo (Meteorologia)RESUMO
UV can serve as an effective light spectrum for regulating plant secondary metabolites, while relevant studies on UV-A are much less extensive than those on UV-B. A comprehensive understanding of the selective effects of UV-A on different secondary metabolites and the specific features of primary metabolism that drive these effects is still lacking. To address this knowledge gap, we conducted a study to analyze the dynamic changes in the metabolome and transcriptome of lettuce leaves irradiated with red plus UV-A light (monochromatic red light as control). Generally, UV-A promoted the synthesis of most phenylpropanoids and terpenoids originating from the shikimate and methylerythritol phosphate (MEP) pathway in plastids but sacrificed the synthesis of terpenoids derived from the mevalonate (MVA) pathway, particularly sesquiterpenes. Increased precursors supply for the shikimate and MEP pathway under UV-A was directly supported by the activation of the Calvin-Benson cycle and phosphoenolpyruvate transport. Whereas, along with phosphoenolpyruvate transport, the TCA cycle was restrained, causing deprivation of the MVA pathway precursor. In addition, UV-A also activated the plastidic oxidative branch of the pentose phosphate pathway, photorespiration, and malate shuttle, to ensure a sufficient supply of nitrogen, circulation homeostasis of the Calvin-Benson cycle, and energy balance, thus indirectly supporting UV-A-induced specific secondary metabolic output. This study provides a comprehensive framework for understanding the flexible primary-secondary metabolism interactions that are able to produce specific metabolites favorable for adaptation to environmental stimuli.
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Lactuca , Folhas de Planta , Metabolismo Secundário , Raios Ultravioleta , Lactuca/metabolismo , Lactuca/efeitos da radiação , Lactuca/química , Lactuca/genética , Lactuca/crescimento & desenvolvimento , Metabolismo Secundário/efeitos da radiação , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Folhas de Planta/química , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Metaboloma/efeitos da radiação , Regulação da Expressão Gênica de Plantas/efeitos da radiação , MultiômicaRESUMO
AIM: To identify genetic defects in a Chinese family with congenital posterior polar cataracts and assess the pathogenicity. METHODS: A four-generation Chinese family affected with autosomal dominant congenital cataract was recruited. Nineteen individuals took part in this study including 5 affected and 14 unaffected individuals. Sanger sequencing targeted hot-spot regions of 27 congenital cataract-causing genes for variant discovery. The pathogenicity of the variant was evaluated by the guidelines of American College of Medical Genetics and InterVar software. Confocal microscopy was applied to detect the subcellular localization of fluorescence-labeled ephrin type-A receptor 2 (EPHA2). Co-immunoprecipitation assay was implemented to estimate the interaction between EphA2 and other lens membrane proteins. The mRNA and protein expression were analyzed by reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting assay, respectively. The cell migration was analyzed by wound healing assay. Zebrafish model was generated by ectopic expression of human EPHA2/p.R957P mutant to demonstrate whether the mutant could cause lens opacity in vivo. RESULTS: A novel missense and pathogenic variant c.2870G>C was identified in the sterile alpha motif (SAM) domain of EPHA2. Functional studies demonstrated the variant's impact: reduced EPHA2 protein expression, altered subcellular localization, and disrupted interactions with other lens membrane proteins. This mutant notably enhanced human lens epithelial cell migration, and induced a central cloudy region and roughness in zebrafish lenses with ectopic expression of human EPHA2/p.R957P mutant under differential interference contrast (DIC) optics. CONCLUSION: Novel pathogenic c.2870G>C variant of EPHA2 in a Chinese congenital cataract family contributes to disease pathogenesis.
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Objective: Analyze the research status of Tourette Syndrome (TS) in children by CiteSpace and determine the current research hotspots and frontiers. Materials and methods: We chose publications indexed in the Web of Science Core Collection (WoSCC) database for studies related to TS in children from 2011 to 2021. We built online cooperation maps of countries/regions, institutions, authors, journals, references, and keywords by CiteSpace, and identified hotspots and frontiers of study for children's TS. Results: A total of 1,232 publications about TS in children were downloaded from the WoSCC. The USA (414) was the country with the highest rate of production, and University College London (87) was the institution that had the highest publication rate. Andrea Eugenio Cavanna was the most prolific author (39 papers). There was inactive cooperation between institutions, countries/regions, and authors. The Journal of European Child & Adolescent Psychiatry was the most active journal. Hot topics focused on epidemiology, comorbidities, deep brain stimulation, behavioral therapy, basal ganglia, pharmacological treatment, and risk factors of TS in children. Conclusion: According to the CiteSpace results, this study found that authors, countries/regions, and institutions were not actively working together. Current research hotspots mainly consist of epidemiology, comorbidities, deep brain stimulation, behavior therapy, and basal ganglia. The main research trends include comorbidities, pharmacological treatment, and risk factors. Therefore, international cooperation should be strengthened in the future, and it should be mindful of the psychiatric comorbidities of TS, the choice of intervention measures, and early warning of risk factors.
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Purpose: To investigate the risk factors and surgical design for type III acute acquired concomitant esotropia (AACE). Methods: In this retrospective, matched, case-control study, 51 patients developed type III AACE between March 2018 and September 2020, and the control group consisted of 60 patients matched by age and refractive power during the same period. A history of the duration of near work per day and the use of glasses were reviewed, and the refractive power of both eyes, deviation angles at both near and far vision, visual function, and treatment options were analyzed. Additionally, the distance from medial rectus insertion to the limbus was measured in surgical patients. The data were analyzed by logistic regression analysis. Results: We found that 99.96% of the patients and 91.67% of the controls had myopia. Of these, 60.8% and 20.0%, respectively, did not wear glasses for near work. Twelve patients were treated with a prism and 39 were treated surgically. The average time devoted to near work per day was 7.24 and 3.7 h by the patients and controls, respectively. Univariate logistic regression analysis showed that increased hours of near work per day and near work without the use of spectacles were associated with the incidence of type III AACE. Multiple logistic regression analysis revealed that increased hours of near work per day and near work without the use of glasses were independent risk factors for AACE. Conclusion: Increased hours of near work per day and uncorrected myopia in near work are independent risk factors for type III AACE.
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Esotropia , Miopia , Doença Aguda , Estudos de Casos e Controles , Humanos , Músculos Oculomotores , Procedimentos Cirúrgicos Oftalmológicos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Visão BinocularRESUMO
BACKGROUND: This study investigated the epidemiological characteristics, predisposing factors, clinical features, microbiological findings, and treatment outcomes of patients with fungal keratitis in southeastern China. METHODS: A retrospective review was carried out on 718 patients diagnosed with fungal keratitis at the the First Affiliated Hospital of Fujian Medical University between January 2004 and December 2017. The sociodemographic data, predisposing factors, clinical details, microbiological findings, and treatment strategies were analyzed. RESULTS: Fungal keratitis was diagnosed in 718 patients (442 male and 276 female; mean age, 41.4±13.1 years). Most patients came from rural areas (79.7%) and farm work was the main occupational activity (51.7%). Cases were more common during the harvest season between October and December (41.6%). Corneal trauma (73.7%), particularly injury with vegetative matter (51.5%), was the predominant predisposing factor. Corneal scrapings obtained from 621 patients were diagnosed as positive on direct microscopy using a 10% potassium hydroxide (KOH) wet mount preparation. The positive culture rate of corneal scrapings was 89.6%. Fungal isolates were Fusarium species in 444 eyes and Aspergillus species in 98 eyes. Antifungal medications were used to treat 529 patients and 189 patients received surgery. CONCLUSIONS: Fungal keratitis is a leading cause of infective corneal ulcers in southeastern China. Corneal trauma was the major predisposing factor and direct microscopic examination was a rapid and sensitive method for diagnosis. The species Fusarium was the most common fungal isolate. Antifungal medication was an effective method for treating early and mild cases.
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Infecções Oculares Fúngicas , Ceratite , Adulto , Antifúngicos/uso terapêutico , China/epidemiologia , Infecções Oculares Fúngicas/tratamento farmacológico , Infecções Oculares Fúngicas/epidemiologia , Feminino , Humanos , Ceratite/tratamento farmacológico , Ceratite/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Demand for spring onion seeds is variable and maintaining its supply is crucial to the success of seed companies. Spring onion seed demand forecasting, which can help reduce the high operational costs increased by long-period propagation and complex logistics, has not previously been investigated yet. This paper provides a novel perspective on spring onion seed demand forecasting and proposes a hybrid Holt-Winters and support vector machine (SVM) forecasting model. The model uses dynamic factors, including historical seed sales, seed inventory, spring onion crop market price and weather data, as inputs to forecast spring onion seed demand. Forecasting error, i.e. the difference between actual and forecasted demand, is assessed. Two advanced machine learning models are trained on the same dataset as benchmark models. Numerical experiments using actual commercial sales data for three spring onion seed varieties show the proposed hybrid model outperformed the statistical-based models for all three forecasting errors. Seed inventory, spring onion crop market price and historical seed sales are the most important dynamic factors, among which seed inventory has short-term influence while other two have mid-term influence on seed demand forecasting. The absolute minimum temperature is the only factor having long-term influence. This study provides a promising spring onion seed demand forecasting model that helps understand the relationships between seed demand and other dynamic factors and the model could potentially be applied to demand forecasting of other crop seeds to reduce total operational costs.
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Previsões/métodos , Cebolas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Produção Agrícola/economia , Abastecimento de Alimentos/economia , Máquina de Vetores de Suporte , Tempo (Meteorologia)RESUMO
Purpose: To investigate the immune response and mechanisms of interferon-γ (IFN-γ) in the fungal keratitis in mice. Methods: Mice were divided into two groups: group A, topical PBS four times daily post-infection; group B: topical IFN-γ four times daily post-infection. At1, 3, 5, and 7 days, the corneal lesions and inflammatory responses were observed by slit lamp, and immunofluorescence staining was performed to evaluate F4/80+ and CD4+ cells. Using ELISA, and RT-PCR to detect the expression levels of macrophage migration inhibitory factor (MIF), macrophage inflammatory protein-2 (MIP-2), IL-4, IL-10, IL-12, and IFN-γ. Results: The treatment with IFN-γ decreased clinical scores and expression levels of IL-4, increased expression of F4/80+ and CD4+ cells, whereas IL-12, MIF, and MIP-2 were expressed highly, and the peaks of IL-10 and IFN-γ move forward. Conclusion: This experiment showed that IFN-γ eye drops increase the accumulation of macrophages and shorten the duration of fungal keratitis.
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Antivirais/uso terapêutico , Úlcera da Córnea/tratamento farmacológico , Citocinas/metabolismo , Infecções Oculares Fúngicas/tratamento farmacológico , Fusariose/tratamento farmacológico , Fusarium/patogenicidade , Interferon gama/uso terapêutico , Administração Oftálmica , Animais , Antivirais/administração & dosagem , Linfócitos T CD4-Positivos/imunologia , Quimiocina CXCL2/metabolismo , Úlcera da Córnea/imunologia , Ensaio de Imunoadsorção Enzimática , Infecções Oculares Fúngicas/imunologia , Fusariose/imunologia , Interferon gama/administração & dosagem , Interleucinas/metabolismo , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Soluções Oftálmicas , Reação em Cadeia da Polimerase em Tempo RealRESUMO
PURPOSE: To explore the inhibitory activity of Lactobacillus salivarius ssp. salivarius JCM1231 (L. salivarius JCM1231) culture filtrate against Fusarium solani (F. solani) and its effects on murine keratocytes (MKs) infected with F. solani. METHODS: L. salivarius JCM1231 was cultured in an anaerobic incubator for 24 h, and the L. salivarius culture filtrate (LSCF) was prepared .The antifungal activity of L. salivarius JCM1231 against F. solani was determined with a plate overlay assay, agar diffusion assay, and conidial germination inhibition test. The effects of temperature, pH, and proteolytic enzymes on the antifungal activity of LSCF were detected with microtiter plate-well assay and conidial germination inhibition assay. Furthermore, the effects of LSCF on MKs infected with F. solani were detected. Cell activity and apoptosis were measured using methylthiazoletetrazolium assays and flow cytometry analysis, respectively. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) cytokines were measured using real-time polymerase chain reactions and enzyme-linked immunosorbent assays (ELISA), and mycotoxin production was detected with high-performance liquid chromatography tandem mass spectrometry. RESULTS: Conidial germination and mycelia growth of F. solani were significantly inhibited by LSCF. The antifungal substances produced by L. salivarius JCM1231 were heat unstable, proteinaceous, and sensitive to proteolytic enzymes and were active within a narrow acidic pH range between 2.0 and 4.0. In the presence of 15 µg/ml of LSCF, cell activity was significantly increased, and cell apoptosis, the level of IL-6 and TNF-α expressions, and mycotoxin (zearalenone and fumonisin B1) productions were decreased significantly in MKs infected with F. solani. CONCLUSION: L. salivarius JCM1231 culture filtrate can effectively inhibit F. solani growth and protect MKs against F. solani infection.
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Antibiose , Ceratócitos da Córnea/microbiologia , Fusarium/crescimento & desenvolvimento , Ligilactobacillus salivarius/fisiologia , Animais , Antibiose/fisiologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Infecções Oculares Fúngicas/prevenção & controle , Citometria de Fluxo , Fumonisinas/metabolismo , Fusariose/prevenção & controle , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Zearalenona/metabolismoRESUMO
Plant-based sensing on water stress can provide sensitive and direct reference for precision irrigation system in greenhouse. However, plant information acquisition, interpretation, and systematical application remain insufficient. This study developed a discrimination method for plant root zone water status in greenhouse by integrating phenotyping and machine learning techniques. Pakchoi plants were used and treated by three root zone moisture levels, 40%, 60%, and 80% relative water content. Three classification models, Random Forest (RF), Neural Network (NN), and Support Vector Machine (SVM) were developed and validated in different scenarios with overall accuracy over 90% for all. SVM model had the highest value, but it required the longest training time. All models had accuracy over 85% in all scenarios, and more stable performance was observed in RF model. Simplified SVM model developed by the top five most contributing traits had the largest accuracy reduction as 29.5%, while simplified RF and NN model still maintained approximately 80%. For real case application, factors such as operation cost, precision requirement, and system reaction time should be synthetically considered in model selection. Our work shows it is promising to discriminate plant root zone water status by implementing phenotyping and machine learning techniques for precision irrigation management.
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Aprendizado de Máquina , Fenômenos Fisiológicos Vegetais , Raízes de Plantas/metabolismo , Plantas/metabolismo , Água , Algoritmos , Modelos Biológicos , Fenótipo , Desenvolvimento Vegetal , Característica Quantitativa Herdável , Curva ROC , Reprodutibilidade dos Testes , Estresse FisiológicoRESUMO
PURPOSE: To investigate the biochemical characteristics in experimental keratomycosis by Raman spectroscopy analysis in vitro and in vivo. METHODS: Raman spectroscopy was used to analyze the biochemical characteristics of cultured mouse keratocytes stimulated by Fusarium solani suspension in vitro, and the infected cornea of Fusarium solani keratitis of mice. RESULTS: The peak intensities at 1005, 1186, 1311, 1449 and 1657 cm-1, which represented phenylalanine, tyrosine, nucleic acid bases, phospholipids and α-helix, were decreased in the infected keratocytes compared with the control keratocytes. The consistency of Raman spectra between the infected cornea tissue and the control cornea tissue was high. However, the intensity of some peaks declined, especially at 853, 940 and 1244 cm-1, which represent the tyrosine, proline and collagen content, respectively. CONCLUSIONS: After infection with Fusarium solani, the biochemical characteristics of keratocyte and cornea showed a decrease of amino acids, nucleic acid phospholipids and collagen, which may closely relate to the pathophysiology of keratomycosis.
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Córnea/fisiopatologia , Infecções Oculares Fúngicas/diagnóstico , Ceratite/diagnóstico , Análise Espectral Raman/métodos , Animais , Fenômenos Biomecânicos , Células Cultivadas , Córnea/microbiologia , Córnea/patologia , Modelos Animais de Doenças , Infecções Oculares Fúngicas/microbiologia , Infecções Oculares Fúngicas/fisiopatologia , Queratinócitos/microbiologia , Queratinócitos/patologia , Ceratite/microbiologia , Ceratite/fisiopatologia , Camundongos Endogâmicos BALB C , Reprodutibilidade dos TestesRESUMO
Purpose. To evaluate the efficacy of a combination of intrastromal and intracameral injections of amphotericin B in the treatment of severe recalcitrant fungal keratitis. Methods. Patients with severe fungal keratitis who were resistant to conventional antifungal medical treatments and needed potential surgical intervention were recruited at the First Affiliated Hospital of Fujian Medical University between January 2012 and July 2013. The patients were treated with a combination of intrastromal and intracameral injections of amphotericin B (25 µg/mL and 50 µg/mL, resp.). Selectively repeated injections were performed as necessary. The efficacy, complications, and outcome were evaluated. Results. Nine patients (9 eyes) were involved in this study. All 9 cases responded favorably, and the clinical appearance of serious corneal damage and intraocular extension was resolved after the treatment. Four eyes required only 1 injection, and 5 eyes required repeated injections. Seven corneal ulcers healed with leucoma, and 2 healed with adherent leucoma. All of our cases had a marked increase in the anterior chamber reaction and pain immediately after the injection. There was no obvious clinical evidence of corneal or lenticular toxicity in any patient. Conclusions. A combination of intrastromal and intracameral injections of amphotericin B may be safe and effective for the treatment of severe fungal keratitis that is resistant to conventional therapy.
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We introduce the large portfolio selection using gross-exposure constraints. We show that with gross-exposure constraint the empirically selected optimal portfolios based on estimated covariance matrices have similar performance to the theoretical optimal ones and there is no error accumulation effect from estimation of vast covariance matrices. This gives theoretical justification to the empirical results in Jagannathan and Ma (2003). We also show that the no-short-sale portfolio can be improved by allowing some short positions. The applications to portfolio selection, tracking, and improvements are also addressed. The utility of our new approach is illustrated by simulation and empirical studies on the 100 Fama-French industrial portfolios and the 600 stocks randomly selected from Russell 3000.
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Immobilized Saccharomyces cerevisiae on the surface of chitosan-coated magnetic nanoparticles (SICCM) was applied as a new magnetic adsorbent for the adsorption of Cu(II) from aqueous solution. The prepared magnetic adsorbent was characterized by TEM, XRD and FTIR. TEM images indicated that S. cerevisiae was immobilized on the surface of chitosan-coated magnetic nanoparticles (CCM) successfully, and conglobation was not observed. The XRD pictures suggested that the Fe(3)O(4) nanoparticles were pure Fe(3)O(4) with a spinel structure and that the immobilizing process did not result in the phase change of Fe(3)O(4). Factors that influence the adsorption of Cu(II) were investigated, which included the initial pH of Cu(II) solution, initial concentration of Cu(II) solution and contact time. The optimum pH for Cu(II) absorption was 4.5. The highest removal efficiency of 96.8% was reached when the initial Cu(II) concentration was 60 mg L(-1), and the adsorption capacity was increased with the increase of initial concentration of Cu(II). In particular, SICCM was highly efficient for the fast adsorption of Cu(II) within the first 10 min, and adsorption equilibrium could be achieved in 1h. Equilibrium studies show that the data of Cu(II) adsorption follow the Langmuir model. The maximum adsorption capacity for Cu(II) was estimated to be 144.9 mg g(-1) with a Langmuir adsorption equilibrium constant of 0.0719 L mg(-1) at 301 K.
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Biodegradação Ambiental , Cobre/farmacocinética , Saccharomyces cerevisiae/metabolismo , Poluentes Químicos da Água/farmacocinética , Adsorção , Células Imobilizadas , Quitosana , Cobre/isolamento & purificação , Magnetismo , Nanopartículas , Saccharomyces cerevisiae/citologia , Soluções , Poluentes Químicos da Água/isolamento & purificaçãoRESUMO
Through the immobilized biosorption of activated carbon and Paenibacillus polymyxa GA1 by sodium alginate, this paper take advantage of the orthogonal experiment to investigate the adsorption characteristics of sodium alginate. According to the research, the optimal preparation conditions were as following: the mass fraction of sodium alginate was 2.5%; the amount of carbon and bacteria was 1:20 and 1:2, respectively; under the preparation condition, the adsorption rate could reach to 93.74%. The adsorption conditions of the immobilized beads were: pH 5, temperature 30 degrees C and Pb2+ with an initial concentration of 300 mg x L(-1). Moreover, the immobilized activated carbon and GA1 improved their application range of pH, temperature and the initial concentration of Pb2+. Based on the equilibrium curve, it showed that the adsorption of Pb2+ was a rapid process within 30 min and gradually reached leveling within 2 h. What's more, the equilibrium curve could be well described by Langmuir model and Freundlich model, which be consisted mainly of monolayer adsorption, and the maximum monolayer adsorption amount was 370.37 mg x g(-1). Finally, the desorption result showed that the immobilized beads could be recycled effectively.