Anterior Segment Tomography with the Cirrus Optical Coherence Tomography

Optical coherence tomography (OCT) is an optical acquisition method to examine biological tissues. In recent years, OCT has become an important imaging technology used in diagnosing and following macular pathologies. Further development enabled application of optical coherence tomography in evaluation of the integrity of the nerve fiber layer, optic nerve cupping, anterior chamber angle, or corneal topography. In this manuscript we overview the use of OCT in the clinical practice to enable corneal, iris, ciliary body, and angle evaluation and diagnostics

In situ degradation of YSZ and YSZ + Al2O3 electrolytes of sensors used in glass melting furnaces

This work reports on the degradation of pure YSZ and YSZ +10 wt% alumina composite electrolytes by exposure to the atmosphere of a heat recovery chamber of an industrial glass furnace, at a temperature around 1300 °C. Microstructural observations and impedance spectroscopy measurements were used to evaluate the corrosion effects. YSZ samples directly placed in the sidewalls and intimately exposed to the dusts and volatiles in the atmosphere show strong corrosion effects after short periods. These samples present large amounts of a glassy phase in the intergranular region, containing the same elements as the common batch with inclusion of volatile species from the fuel. At the same time, the average composition of YSZ grains remains almost unchanged. Effects on the electrical properties are obviously stronger in the intergranular response, as confirmed by changes in the typical relaxation frequency. The protection of samples and/or their careful placement in the furnace strongly inhibit the corrosion process. The effectiveness of alumina addition to the YSZ electrolyte in increasing its corrosion resistance was only tested in protected samples, where the corrosion is less severe. For this reason, the expected benefits of this incorporation were found almost irrelevant

Por uma agenda da paz nas Relações Internacionais do Brasil

Dada a falta de pesquisas sistemáticas sobre a paz na academia brasileira de Relações Internacionais, o artigo clama pela inclusão do tema nos debates científicos nacionais.Dada a falta de pesquisas sistemáticas sobre a paz na academia brasileira de Relações Internacionais, o artigo clama pela inclusão do tema nos debates científicos nacionais

Simulações computacionais para os efeitos da regulação ambiental sobre o crescimento e a dinâmica industrial- uma abordagem evolucionária

Este trabalho traz uma abordagem evolucionária para a discussão da problemática ambiental, propondo uma visão não concorrente (como realizada pela teoria convencional) entre economia e meio ambiente. Sugere-se a integração da variável ambiental como estratégia competitiva das firmas. Através do método de simulação computacional verificaram-se a eficácia de três tipos de políticas, todas diferentes quanto ao seu grau de restrição, quais sejam- um imposto ambiental, um subsídio à P&D “verde”, e um programa de educação ambiental que se traduz no mercado como uma preferência do consumidor à um produto ecológico. Foram simulados nove tipos de combinações derivados dessas políticas, com diferentes valores de parâmetros, a fim de se testar a sensibilidade das variáveis econômicas à estas políticas. Assim, objetivou-se averiguar qual tipo de política gera o melhor resultado ambiental, e suas conseqüências para a dinâmica industrial. Como principal conclusão, encontrou-se que o resultado da política ambiental depende do seu grau de restrição, corroborando com o que Porter chama de “boa regulamentação”.

Leishmania amazonensis promastigotes in 3D Collagen I culture: an in vitro physiological environment for the study of extracellular matrix and host cell interactions

Leishmania amazonensis is the causative agent of American cutaneous leishmaniasis, an important neglected tropical disease. Once Leishmania amazonensis is inoculated into the human host, promastigotes are exposed to the extracellular matrix (ECM) of the dermis. However, little is known about the interaction between the ECM and Leishmania promastigotes. In this study we established L. amazonensis promastigote culture in a three-dimensional (3D) environment mainly composed of Collagen I (COL I). This 3D culture recreates in vitro some aspects of the human host infection site, enabling the study of the interaction mechanisms of L. amazonensis with the host ECM. Promastigotes exhibited “freeze and run” migration in the 3D COL I matrix, which is completely different from the conventional in vitro swimming mode of migration. Moreover, L. amazonensis promastigotes were able to invade, migrate inside, and remodel the 3D COL I matrix. Promastigote trans-matrix invasion and the freeze and run migration mode were also observed when macrophages were present in the matrix. At least two classes of proteases, metallo- and cysteine proteases, are involved in the 3D COL I matrix degradation caused by Leishmania. Treatment with a mixture of protease inhibitors significantly reduced promastigote invasion and migration through this matrix. Together our results demonstrate that L. amazonensis promastigotes release proteases and actively remodel their 3D environment, facilitating their migration. This raises the possibility that promastigotes actively interact with their 3D environment during the search for their cellular “home”—macrophages. Supporting this hypothesis, promastigotes migrated faster than macrophages in a novel 3D co-culture model

Fundus Autofluorescence in Multiple Evanescent White Dot Syndrome

A patient complained of photopsia and vision loss in the left eye for two days, with visual acuity of 20/32. Right eye was normal. Funduscopy revealed foveal granularity and gray-white lesions in the posterior pole, mainly temporal to the fovea. The lesions (dots and spots), along with a few other areas surrounding them, showed hyperautofluorescence on autofluorescence imaging. Fluorescein angiogram (FA) depicted some early hyperfluorescent dots with late staining. Indocyanine green angiogram (ICGA) showed hypofluorescent lesions in a greater number compared with funduscopy, autofluorescence, and FA. Thirty days later, BCVA was 20/20 in both eyes and the complimentary exams were almost normal, despite an ICGA that showed few small hypofluorescent lesions. This case supports the hypothesis that the choroidal involvement occurs primarily in MEWDS, with secondary involvement of the RPE and the neurosensory retina

Staphylococcus epidermidis biofilms are resistant to phage infection due to the protective effect of the biofilm matrix

EMBO Conference on Viruses of Microbes III: Structure and Function - from Molecules to Communities (Programme and Abstract Book)info:eu-repo/semantics/publishedVersio

Highly Enantioselective Iridium(I)-Catalyzed Hydrocarbonation of Alkenes: A Versatile Approach to Heterocyclic Systems Bearing Quaternary Stereocenters

We report a versatile, highly enantioselective intramolecular hydrocarbonation reaction that provides a direct access to heteropolycyclic systems bearing chiral quaternary carbon stereocenters. The method, which relies on an iridium(I)/bisphosphine chiral catalyst, is particularly efficient for the synthesis of five-, six- and seven-membered fused indole and pyrrole products, bearing one and two stereocenters, with enantiomeric excesses of up to >99 %. DFT computational studies allowed to obtain a detailed mechanistic profile and identify a cluster of weak non-covalent interactions as key factors to control the enantioselectivityThis work received financial support from the Spanish MINECO (SAF2016-76689-R, PID2019-108624RB-I00, CTQ2017-84767-P, PID2020-118579GB-I00), the Xunta de Galicia (ED431C 2017/19, 2015-CP082, Centro Singular de Investigación de Galicia accreditation 2019-2022, ED431G 2019/03, a predoctoral Fellowship to A. A. and M. C. and a postdoctoral Fellowship to D. F. F, ED481B-2019-005) and the ERDF, ERC (Adv. Grant No. 340055). The Orfeo-Cinqa network (CTQ2016-81797-REDC)S