460 research outputs found

    Impacto da COVID-19 na Cirurgia de Transplantação Corneana: Primeiro EuCornea Educational Webinar

    Get PDF
    info:eu-repo/semantics/publishedVersio

    Outcomes of Cystoid Macular Edema Following Descemet's Membrane Endothelial Keratoplasty in a Referral Center for Keratoplasty in Spain: Retrospective Study

    Get PDF
    The aim of this study was to analyze the outcomes of eyes with visually significant cystoid macular œdema (vs-CMO) after Descemet membrane endothelial keratoplasty (DMEK) in a referral center for keratoplasty in Spain. We conducted a retrospective, single-surgeon case series of eyes that developed post-DMEK vs-CMO performed between January 2011 and December 2020. Data collected included: indication for DMEK; biometric data; ocular comorbidities; past medical history; time to detection of vs-CMO after DMEK (T, weeks); best-corrected visual acuity (BCVA, logMAR) and central retinal thickness (CRT, µm) at diagnosis of vs-CMO, after resolution of CMO, and at last follow-up; and management strategy. Main outcomes analyzed were incidence of vs-CMO, improvement in BCVA and CRT after treatment of vs-CMO. Of 291 consecutive DMEK surgeries, 14 eyes of 13 patients (4.8%) developed vs-CMO. Five patients (38.5%) had history of CMO, and 28.6% of eyes had ophthalmic comorbidities. Median (P25-P75) T was 4 (3-10) weeks. Treatment success was observed in 12/13 eyes (92.3%), two of which required second-line treatment. In successful cases (median time-to-resolution 3.0 (2.0-3.5) months), median BCVA improved from 0.60 (0.40-0.80) logMAR to 0.30 (0.15-0.40) logMAR (p = 0.002) after treatment, and median CRT improved from 582.5 (400.0-655.0) µm to 278.0 (258.0-294.0) µm (p = 0.005). In our study, we found a 4.8% rate of post-DMEK vs-CMO, with most cases occurring in the first 3 months after surgery. Good functional and anatomical outcomes are expected in most eyes, without treatment-related complications or implications in graft outcomes. Additional studies are encouraged to determine a standardized protocol for post-DMEK vs-CMO.info:eu-repo/semantics/publishedVersio

    Pseudo-single crystal electrochemistry on polycrystalline electrodes : visualizing activity at grains and grain boundaries on platinum for the Fe2+/Fe3+ redox reaction

    Get PDF
    The influence of electrode surface structure on electrochemical reaction rates and mechanisms is a major theme in electrochemical research, especially as electrodes with inherent structural heterogeneities are used ubiquitously. Yet, probing local electrochemistry and surface structure at complex surfaces is challenging. In this paper, high spatial resolution scanning electrochemical cell microscopy (SECCM) complemented with electron backscatter diffraction (EBSD) is demonstrated as a means of performing ‘pseudo-single-crystal’ electrochemical measurements at individual grains of a polycrystalline platinum electrode, while also allowing grain boundaries to be probed. Using the Fe2+/3+ couple as an illustrative case, a strong correlation is found between local surface structure and electrochemical activity. Variations in electrochemical activity for individual high index grains, visualized in a weakly adsorbing perchlorate medium, show that there is higher activity on grains with a significant (101) orientation contribution, compared to those with (001) and (111) contribution, consistent with findings on single-crystal electrodes. Interestingly, for Fe2+ oxidation in a sulfate medium a different pattern of activity emerges. Here, SECCM reveals only minor variations in activity between individual grains, again consistent with single-crystal studies, with a greatly enhanced activity at grain boundaries. This suggests that these sites may contribute significantly to the overall electrochemical behavior measured on the macroscale

    Structural correlations in heterogeneous electron transfer at monolayer and multilayer graphene electrodes

    Get PDF
    As a new form of carbon, graphene is attracting intense interest as an electrode material with widespread applications. In the present study, the heterogeneous electron transfer (ET) activity of graphene is investigated using scanning electrochemical cell microscopy (SECCM), which allows electrochemical currents to be mapped at high spatial resolution across a surface for correlation with the corresponding structure and properties of the graphene surface. We establish that the rate of heterogeneous ET at graphene increases systematically with the number of graphene layers, and show that the stacking in multilayers also has a subtle influence on ET kinetics. © 2012 American Chemical Society

    Effect of foliar application of boron, zinc and calcium on onion seed production = Efecto de la aplicación foliar de boro, zinc y calcio en la producción de semilla de cebolla

    Get PDF
    La semilla de cebolla representa un alto porcentaje del valor económico total de semillas de hortalizas comercializado en el mundo. En Argentina, la producción de semilla de cebolla se realiza en San Juan y Mendoza y se utilizan cultivares de polinización abierta (OP) e híbridos de primera generación. Una variedad OP tiene buenos rendimientos de semilla, pero el rendimiento de semillas híbridas es errático y considerablemente más bajo. El rendimiento y la calidad de semilla dependen, entre otros factores, de la fertilización. Nutrientes tales como boro, zinc y calcio son esenciales para el crecimiento y el desarrollo de las plantas. La fertilización foliar permite suministrar nutrientes sobre órganos específicos cuando la etapa de crecimiento, la demanda interna y las condiciones ambientales limitan su entrega. El objetivo de este estudio fue evaluar el efecto de la aplicación foliar de boro, zinc y calcio, sobre el rendimiento y la calidad de semilla de cebolla. El estudio se realizó sobre la cv. Angaco INTA en una finca comercial ubicada en el departamento de Pocito, San Juan. Se utilizó un diseño completamente aleatorizado con cuatro repeticiones. Se evaluaron tres dosis de boro, de calcio y de zinc, más una combinación de los mismos y el testigo. Se concluye que la aplicación foliar de boro, tanto simple como combinado con zinc y calcio, produce un mayor cuajado de frutos, mientras que el calcio mejora el poder germinativo. No se observaron efectos significativos en el rendimiento de semillas.Onion seed represents a high percentage of the total economic value of vegetable seeds marketed worldwide. In Argentina, onion seed production is carried out in San Juan and Mendoza, where open-pollination (OP) cultivars and first generation hybrids are used. An OP variety has good seed yield, but the yield of hybrid seeds is erratic and considerably lower. Seed yield and quality depends, among other factors, on fertilization. Nutrients such as boron, zinc and calcium are essential for the growth and development of plants. Foliar fertilization allows the supply of nutrients to specific organs when the growth stage, internal demand and environmental conditions limit their delivery. The objective of this study was to evaluate the effect of the foliar application of boron, zinc and calcium, on the yield and quality of onion seed. The study was conducted on cv. Angaco INTA in a commercial farm located in the department of Pocito, San Juan. A completely randomized design with four replications was used. Three doses of boron, calcium and zinc, plus a combination of the three nutrients and the control were evaluated. The foliar application of boron, both simple and combined with zinc and calcium, produces a greater fruit set, while calcium improves germination. No significant effects on seed yield were observed.EEA San JuanFil: Gabri Martín, Carlos Guillermo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina.Fil: Gabri Martín, Carlos Guillermo. Universidad Nacional de San Juan. Departamento de Agronomía. Facultad de Ingeniería; Argentina.Fil: Gabri Martín, Carlos Guillermo. Universidad Nacional de Cuyo. Facultad de Ciencia Agrarias; ArgentinaFil: Ibañez, Antonio Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Juan; Argentina.Fil: Güell, J. M. Universidad Nacional de San Juan. Departamento de Agronomía. Facultad de Ingeniería; Argentina.Fil: Galmarini, Claudio Rómulo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria La Consulta; Argentina.Fil: Galmarini, Claudio Rómulo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    A conceptual framework to safeguard the neuroright to personal autonomy

    Get PDF
    In this article, we propose a philosophical exploration on the main problems involved in two neurorights that concern autonomous action, namely free will and cognitive liberty, and sketch a possible solution to these problems by resourcing to a holistic interpretation of human actions. First, we expose the main conceptual and practical issues arising from the neuroright to free will, which are far from minor: the term itself is denied by some trends participating in the neurorights debate, the related concept of ultimate control is also disputed, the understanding of free will depends on cultural context, and the exercise of being free to act in several domains may be covered by other regulations. Second, we analyze the historical origin of cognitive liberty, its current status, and its relation with free will. Third, we criticize the concept of decision in mainstream action theory and propose to conceive action as a unified process constituted by three explanatory, non-sequential dimensions: intention, decision, and action realization. Fourth, we discuss two possible cases involving neurotechnologies and suggest ways to interpret them according to a unified framework in which free will and cognitive liberty fall under a single neuroright to personal autonomy. Finally, we outline a recommendation to introduce freedom of thought and personal autonomy as complementary neurorights to protect both the internal and external dimensions of thought and action

    Atypical parkinsonism-associated retromer mutant alters endosomal sorting of specific cargo proteins

    Get PDF
    The retromer complex acts as a scaffold for endosomal protein complexes that sort integral membrane proteins to various cellular destinations. The retromer complex is a heterotrimer of VPS29, VPS35, and VPS26. Two of these paralogues, VPS26A and VPS26B, are expressed in humans. Retromer dysfunction is associated with neurodegenerative disease, and recently, three VPS26A mutations (p.K93E, p.M112V, and p.K297X) were discovered to be associated with atypical parkinsonism. Here, we apply quantitative proteomics to provide a detailed description of the retromer interactome. By establishing a comparative proteomic methodology, we identify how this interactome is perturbed in atypical parkinsonism-associated VPS26A mutants. In particular, we describe a selective defect in the association of VPS26A (p.K297X) with the SNX27 cargo adaptor. By showing how a retromer mutant leads to altered endosomal sorting of specific PDZ ligand–containing cargo proteins, we reveal a new mechanism for perturbed endosomal cargo sorting in atypical parkinsonism
    corecore