Development and Application of an Automated Raman Sensor for Bioprocess Monitoring: From the Laboratory to an Algae Production Platform.

Microalgae provide valuable bio-components with economic and environmental benefits. The monitoring of microalgal production is mostly performed using different sensors and analytical methods that, although very powerful, are limited to qualified users. This study proposes an automated Raman spectroscopy-based sensor for the online monitoring of microalgal production. For this purpose, an in situ system with a sampling station was made of a light-tight optical chamber connected to a Raman probe. Microalgal cultures were routed to this chamber by pipes connected to pumps and valves controlled and programmed by a computer. The developed approach was evaluated on Parachlorella kessleri under different culture conditions at a laboratory and an industrial algal platform. As a result, more than 4000 Raman spectra were generated and analysed by statistical methods. These spectra reflected the physiological state of the cells and demonstrate the ability of the developed sensor to monitor the physiology of microalgal cells and their intracellular molecules of interest in a complex production environment.

Novel hybrid evolutionary algorithm for bi-objective optimization problems.

This work considers the Bi-objective Traveling Salesman Problem (BTSP), where two conflicting objectives, the travel time and monetary cost between cities, are minimized. Our purpose is to compute the trade-off solutions that fulfill the problem requirements. We introduce a novel three-Phase Hybrid Evolutionary Algorithm (3PHEA) based on the Lin-Kernighan Heuristic, an improved version of the Non-Dominated Sorting Genetic Algorithm, and Pareto Variable Neighborhood Search, a multi-objective version of VNS. We conduct a comparative study with three existing approaches dedicated to solving BTSP. To assess the performance of algorithms, we consider 20 BTSP instances from the literature of varying degrees of difficulty (e.g., euclidean, random, mixed, etc.) and different sizes ranging from 100 to 1000 cities. We also compute several multi-objective performance indicators, including running time, coverage, hypervolume, epsilon, generational distance, inverted generational distance, spread, and generalized spread. Experimental results and comparative analysis indicate that the proposed three-phase method 3PHEA is significantly superior to existing approaches covering up to 80% of the true Pareto fronts.

Does Variability Affect the Performance of Front-Face Fluorescence Spectroscopy? A Study Case on Commercial Lebanese Olive Oil.

The potential of front-face fluorescence spectroscopy coupled with chemometric techniques, namely multiple linear regression (MLR) applied on parallel factor (PARAFAC) scores and partial least squares (PLS), was tested on Lebanese olive oil samples possessing natural variability within their chemical parameters. Ninety-six olive oil samples have been harvested at different dates and from two seasons, processed using different extraction methods, collected from different altitudes and other factors that can increase the variability of the samples' chemical composition. Fluorescence excitation-emission matrices (EEM) of the collected samples were measured, and the relationship between them and the chemical parameters was examined. Twenty-two MLR regression models based on PARAFAC scores were generated, the majority of which showed a good correlation coefficient (R > 0.7 for ten predicted variables). A second model using PLS on the unfolded EEM was also conducted to improve the regression and to assess if it can handle the variability in hand. However, similar results, with a slight improvement over the MLR model, were obtained. In a non-experimental design, such variability may hinder the potentials of front-face fluorescence; however average to good MLR and PLS models were obtained, predicting the Lebanese olive oil deterioration quality parameters and fatty acid content.

Encapsulation of curcumin in cyclodextrin-metal organic frameworks: Dissociation of loaded CD-MOFs enhances stability of curcumin.

Curcumin has been successfully encapsulated in cyclodextrin-metal organic frameworks (CD-MOFs) without altering their crystallinity. The interaction between curcumin and CD-MOFs is strong through hydrogen bond type interaction between the OH group of cyclodextrin of CD-MOFs and the phenolic hydroxyl group of the curcumin. Interestingly, dissolving the curcumin loaded CD-MOFs crystals in water results in formation of a unique complex between curcumin, γCD and potassium cations. In fact, the initial interaction between curcumin and CD-MOF is crucial for the formation of the latter. This new complex formed in alkaline media at pH 11.5 has maximum absorbance at 520nm and emittance at 600nm. Most importantly, the stability of curcumin in this complex was enhanced by at least 3 orders of magnitude compared to free curcumin and curcumin:γ-CD at pH 11.5. These results suggest a promising benign system of CD-MOFs, which can be used to store and stabilize curcumin for food applications.

Facoemulsificação sob anestesia tópica realizada por residentes do terceiro ano de Oftalmologia / Phacoemulsification under topical anesthesia performed by third year Ophthalmology residents

OBJETIVOS: Avaliar a eficácia e a segurança da transição da cirurgia de facoemulsificação sob anestesia peribulbar para tópica realizadas por residentes do terceiro ano. MÉTODOS: Os prontuários dos pacientes submetidos à facoemulsificação no período de agosto de 2004 a janeiro de 2005 foram analisados. Os pacientes foram operados sob anestesia tópica (grupo I) e peribulbar (grupo II).Foram obtidos dados referentes a sexo, idade, acuidade visual com estenopeico e complicações. Foram excluídos pacientes com baixa acuidade visual não devido à catarata. RESULTADOS: Cento e cinqüenta e um (151) olhos foram avaliados; 70 olhos no grupo I e 81 no grupo II. A acuidade visual pósoperatória com estenopeico aos seis meses foi superior a logMAR +0,30 em 80,7 por cento e a média foi de log MAR +0.10 em ambos os grupos. As análises das complicações intraoperatórias entre os grupos I e II mostrou diferença estatisticamente significante (p=0,039). CONCLUSÃO: Nossos dados sugerem que a transição para cirurgia de facoemulsificação sob anestesia tópica realizadas por residentes de terceiro ano é eficaz e segura.

PURPOSE: To evaluate the outcome and safety of the transition from phacoemulsification performed by third year residents using peribulbar anesthesia to topical anesthesia. METHODS: Cases performed by third year residents from august 2004 to february 2005 were analyzed. Patients were operated under peribulbar (group I) and topical anesthesia (group II). Variables analyzed included patients age, sex, visual acuity under pinhole and complications. Patients with low visual acuity other than cataract were excluded from analysis. RESULTS: A total of 151 eyes were analyzed; 70 eyes in group I and 81 in group II. The visual acuity with pinhole as better than logMAR +0,30 in 80,7 percent and the average visual acuity after six months was log MAR +0.10 for both groups.The complication rate diference between both groups was statistically significant (p=0,039). CONCLUSION: Our data suggests that transition to topical anesthesia performed by third year residents is safe with similar outcomes.

Abordagem da Catarata Congênita: análise de série de casos / Approach to Congenital Cataract: case series analysis

A catarata congênita é uma causa importante de deficiência visual, principalmente por ambliopia, com prevalência aproximada de 0,4%. Seu manejo cirúrgico, inclusive em crianças, tem se desenvolvido, levando a melhores resultados visuais e contribuindo para o controle da ambliopia. OBJETIVO: Relatar os resultados precoces de uma série de casos submetidos a diferentes modalidades cirúrgicas para catarata congênita no Serviço de Catarata do Instituto de Oftalmologia Tadeu Cvintal (IOTC) de janeiro de 2004 a janeiro de 2005. MÉTODOS: Estudo retrospectivo em 19 crianças (32 olhos) com catarata congênita. A série de casos foi dividida em três grupos de acordo com a abordagem cirúrgica: lensectomia via pars plana, facoaspiração com e sem implante de lente intraocular. A acuidade visual corrigida final foi registrada com quatro meses de pós-operatório. RESULTADOS: Oito olhos foram submetidos à lensectomia, treze (13) à facoaspiração com implante de lente intra-ocular, e onze (11) à facoaspiração sem implante de lente intra-ocular. Em dez olhos foi realizada capsulotomia posterior primária. A única complicação observada foi opacidade de cápsula posterior em 60% (n=05) dos casos. Aproximadamente 43% dos pacientes (n=14) desenvolveram AV final corrigida entre 20/20 (LogMAR + 0.0) e 20/40 (LogMAR +0.3). Destes, oito (57%) eram olhos de crianças operadas de ambos os olhos (catarata bilateral). A média de idade em que foram operadas, neste grupo de melhor acuidade, foi de sete anos. Sete (50%) olhos foram submetidos a facoaspiração com implante de lente intra-ocular, e cinco (35%) destes foram submetidos á capsulotomia posterior secundária. CONCLUSÃO: A série de casos analisada apresentou bons resultados cirúrgicos e funcionais precoces, embora trata-se de um número pequeno e heterogêneo de pacientes. O acompanhamento a longo prazo desses pacientes é essencial para avaliarmos que papel as diferentes...

INTRODUCTION: Congenital cataract is an important cause of poor visual acuity and amblyopia, with an incidence of 0,4 percent. Surgical approaches in children present many advances through the years, such as intraocular lenses implantation and others thechniques, wich results in better visual outcomes and prevention of amblyopia. PURPOSE: To report the early outcomes of a series of cases submited to different surgical techiniques for pediatric cataract, in the Tadeu Cvintal Ophthalmology Institute, from January 2004 to January 2005. METHODS: Retrospective study in 19 children (32 eyes) with congenital cataract. The surgical management was separated in three series: pars plana lensectomy, phacoaspiration with or without intraocular lenses; and also separated in patients who had been submitted to posterior capsulotomy. Visual acuity has been tested with four months of follow up. RESULTS: Lensectomy was performed on eight cases, phacoaspiration with intraocular lenses implantation on 13, phacoaspiration without intraocular lenses on 11. Ten eyes had primary posterior capsulotomy, 13 had secondary posteior capsulotomy one month after initial surgery, nine did not need secondary surgery for capsular opacification. The only observed complication was capsule opacification in 60% of the cases. Fourteen (14) eyes (43%) had visual acuity between 20/20 and 20/40 (LoGMAR +0.0 to + 0.3), from which eight were operated on bilateral cataract. The mean age in the group with best visual acuity was 7 years old. Seven eyes from this group (50%) had phacoaspiration with intraocular lenses implantation, and five (35%) with secondary capsulotomy. CONCLUSIONS: This series showed good visual and functional early outcomes, even with a small and heterogeneous sample. A longer follow-up is needed to evaluate the different prognosis for each surgical technique.

Trabeculectomia preservando a integridade da Cápsula de Tenon em casos de pobre prognóstico / Trabeculectomy preserve Tenon's capsule integrity in cases of poor prognosis

Introdução: A trabeculectomia é uma técnica cirúrgica que objetiva a diminuição da pressão intra-ocular (PIO), através da criação de uma fístula que permite o livre fluxo do humor aquoso entre a câmara anterior e o espaço sub-tenoniano. Alterações inflamatórias no nível da Cápsula de Tenon representam uma causa comum de falência da trabeculectomia. O objetivo deste estudo é apresentar nossa experiência com cirurgias filtrantes nos casos de glaucoma, onde a intenção foi minimizar a injúria à Cápsula de Tenon. Local: Instituto de Oftalmologia Tadeu Cvintal, São Paulo. Pacientes e Métodos: Realizamos a trabeculectomia preservando a integridade da Cápsula de Tenon, segundo a técnica descrita por Van Buskik, modificada por Fabian Lerner em 16 pacientes, considerados de mau prognóstico. Uma peritomia conjuntival de 3.0mm é realizada sem lesar a Cápsula de Tenon. Uma incisão de espessura parcial é feita no limbo e um flap escleral é dissecado 3mm posteriormente. O espaço subconjuntival é atingido com um cistótomo, que passa através da bolsa escleral criada após a confecção do flap. A seguir é feita injeção de solução salina balanceada (BSS, Alcon laboratories, Ft. Worth, TX) misturada com 5-fluoracil (5mg) em todos os casos. A câmara anterior é atingida através de uma incisão próxima ao limbo. Um fragmento de 1,5 por 1,0mm no assoalho da bolsa escleral e ressecado, seguido de uma iridectomia periférica. Por fim, a esclera e a conjuntiva são suturadas com pontos isolados de nylon 10-0. Resultados: A PIO pré-operatória era de 36 +/- 4mmHg e a PIO atingida no pós-operatório foi de 14 +/- 2mmHg em 6 meses, sendo que 75 por cento dos olhos atingiram níveis de PIO menor ou igual a 15mmHg sem medicação. O tempo de seguimento pós-operatório médio foi de 12 meses, variando de 8 a 14 meses. Nenhuma complicação séria foi evidenciada. Conclusão: Tempos de seguimentos pós-operatórios mais extensos mostram que essa nova técnica é um procedimento seguro e capaz de reduzir os níveis de PIO com eficácia. Sugerimos o uso dessa técnica, especialmente em casos de pobre prognóstico, obtendo-se resultados melhores que os encontrados com o procedimento convencional.