Art echo: María Zambrano and the Kouroi Relief

The aim of this paper is to examine the role of early Greek thought in the work of María Zambrano, a Spanish critic and philosopher who lived most of her life in exile (1939 - 1984). Zambrano incorporates Greek concepts into her writing as a means to question conventional Philosophy, not as an aim or télos, but as an uncomfortable dwelling that paradoxically leads into suspension and doubt. Key concepts and artistic figures emerge in her seemingly illogical reasoning (‘razón poética’) such as those arising from her work on the Greek ‘Kouroi.’ Zambrano refuses fixity in Philosophy, where logic and method can be rigorously apprehended. She gracefully takes another turn: by elucidating ancient wisdom through allusive metaphors and ancient ruins, she resists direct pathways into History and Truth. Her style takes after her thinking and can often meander into the realms of enigma, mysticism, and other unconventional forms of thought such as intuition and dreams

Carmen Conde: contadora de Gabriela Mistral

This article explores the relationship between Carmen Conde and Gabriela Mistral mainly through their correspondence which they exchanged from 1933-1952. This is the first time that their letters and postcards have been published together, and from them we can observe their anxieties and frustrations felt before and after the Spanish Civil War. Their correspondence offers us insight into their relationship, at times intimate, at times controversial (especially when reading Mistral). It is important to note that Mistral was the consul in Spain from 1933-1935 and was often busy with diplomatic duties. But it is also clear that she helped a number of young Spanish writers, including Conde, in their literary career. In her letters we can read how instrumental she was in helping Conde. When reading Conde's interpretation of Mistral, we find that it can be quite mixed. Even so, in her letters we see how much Conde honoured and respected Mistral, including imagining herself part of Mistral’s poetic community.<p></p> Este artículo muestra la relación epistolar entre Carmen Conde y Gabriela Mistral, abordando por primera vez la correspondencia (1933-1952) entre las dos autoras, revelando sus ideales y preocupaciones como escritoras en España, en los años 30. El ensayo muestra también la imagen que Conde construyó de Mistral, en la medida en que la última se permitió revelar o compartir su tiempo para ayudar a Conde en su carrera literaria. No se puede interpretar ésta como una relación pareja, pues se debe de considerar que Mistral era cónsul en Madrid (1933-1935) y que tenía que ser prudente con su tiempo y con la gente que le rodeaba. Este artículo busca aportar una mirada nueva, femenina y enriquecedora, de una época anterior a la guerra civil española y, por otra parte, presenta algunos detalles de los difíciles tiempos que vivieron las dos autoras.<p></p&gt

Efficacy of antiplatelet therapy in secondary prevention following lacunar stroke:Pooled analysis of randomized trials

Background and Purpose: Lacunar stroke accounts for ≈25% of ischemic stroke, but optimal antiplatelet regimen to prevent stroke recurrence remains unclear. We aimed to evaluate the efficacy of antiplatelet agents in secondary stroke prevention after a lacunar stroke. Methods: We searched MEDLINE, Embase, and the Cochrane library for randomized controlled trials that reported risk of recurrent stroke or death with antiplatelet therapy in patients with lacunar stroke. We used random effects meta-analysis and evaluated heterogeneity with I2. Results: We included 17 trials with 42 234 participants (mean age 64.4 years, 65% male) and follow up ranging from 4 weeks to 3.5 years. Compared with placebo, any single antiplatelet agent was associated with a significant reduction in recurrence of any stroke (risk ratio [RR] 0.77, 0.62–0.97, 2 studies) and ischemic stroke (RR 0.48, 0.30–0.78, 2 studies), but not for the composite outcome of any stroke, myocardial infarction, or death (RR 0.89, 0.75–1.05, 2 studies). When other antiplatelet agents (ticlodipine, cilostazol, and dipyridamole) were compared with aspirin, there was no consistent reduction in stroke recurrence (RR 0.91, 0.75–1.10, 3 studies). Dual antiplatelet therapy did not confer clear benefit over monotherapy (any stroke RR 0.83, 0.68–1.00, 3 studies; ischemic stroke RR 0.80, 0.62–1.02, 3 studies; composite outcome RR 0.90, 0.80–1.02, 3 studies). Conclusions: Our results suggest that any of the single antiplatelet agents compared with placebo in the included trials is adequate for secondary stroke prevention after lacunar stroke. Dual antiplatelet therapy should not be used for long-term stroke prevention in this stroke subtype

Sodium sulfate crystallisation monitoring using IR Thermography

In this work, the evaporation of sodium sulfate droplets with different concentrations and at different temperatures were studied using infrared thermography (IRT). IRT allows to detect the evaporation evolution, the crystal growth and for the first time, to observe in vivo the heat release related to sodium sulfate crystallisation. A detailed study revealed that dendritic Thenardite III crystals appeared at the edge of all the crystallised droplets, though they showed a fast increase of temperature related to crystallisation only when a hydrated phase crystallised also from the droplet. The observation of the heat of crystallisation is thus directly related to the supersaturation of the droplet and consequently to temperature. In addition, IRT detection is circumscribed by the location of crystallisation. The heat can be observed and measured only when the crystallisation occurs in the interface solution – air

Nicotinic Acid Receptor Abnormalities in Human Skin Cancer: Implications for a Role in Epidermal Differentiation

Chronic UV skin exposure leads to epidermal differentiation defects in humans that can be largely restored by pharmacological doses of nicotinic acid. Nicotinic acid has been identified as a ligand for the human G-protein-coupled receptors GPR109A and GPR109B that signal through G(i)-mediated inhibition of adenylyl cyclase. We have examined the expression, cellular distribution, and functionality of GPR109A/B in human skin and skin derived epidermal cells.Nicotinic acid increases epidermal differentiation in photodamaged human skin as judged by the terminal differentiation markers caspase 14 and filaggrin. Both GPR109A and GPR109B genes are transcribed in human skin and in epidermal keratinocytes, but expression in dermal fibroblasts is below limits of detection. Receptor transcripts are greatly over-expressed in squamous cell cancers. Receptor protein in normal skin is prominent from the basal through granular layers of the epidermis, with cellular localization more dispersive in the basal layer but predominantly localized at the plasma membrane in more differentiated epidermal layers. In normal human primary and immortalized keratinocytes, nicotinic acid receptors show plasma membrane localization and functional G(i)-mediated signaling. In contrast, in a squamous cell carcinoma derived cell line, receptor protein shows a more diffuse cellular localization and the receptors are nearly non-functional.The results of these studies justify future genetic and pharmacological intervention studies to define possible specific role(s) of nicotinic acid receptors in human skin homeostasis

Producción de harina de papa para puré instantáneo

In this study, potatoes flour for instant purée was produced using national potato varieties Provento and Granola. For this, the moisture content of potatoes was determined; the results showed that the Granola variety has lower moisture range and higher dry matter. Also, the effectiveness of physicochemical treatments (temperature, reduction of atmospheric oxygen and the use of chemical reagents) was studied for inhibition of polyphenol oxidase enzyme in the potatoes. The results showed that heat treatments, without the use of chemical agents, were the best choice for enzyme inhibition. The determination of the drying curves for potato paste, with pretreatment, was conducted in a drying tunnel at 60 ° C and an air velocity of 0.2 m/s. The pre-treatments include blanching, cooking, and the use of ascorbic acid and sodium metabisulfite. The results indicated that the applying heat treatment to potatoes was sufficient to prevent enzymatic browning and also, a lower drying time is achieved. Experimental data were evaluated using Midilli model, showing a good fit with an R2 > 0.99. Also, it was found that the optimal method for the preparation of potato flour involves the following steps: cooking, cooling and dry size reduction. This ensures that the flour, according to the results of swelling power, solubility in water and water absorption, reaches instant starch characteristics favoring the formation of a puree quickly. Yields in flour production range from 12.55 to 14.09% for Granola and between 11.18 to 15.58% for Provento wet basis. DOI: http://dx.doi.org/10.5377/nexo.v27i2.1946Este estudio se basó en la producción de harina de papa para puré instantáneo, utilizando las variedades de papas nacionalesProvento y Granola. Para ello, se determinó el porcentaje de humedad de las papas, resultando la variedad Granola con el menorrango de humedad y mayor contenido de materia seca. Adicionalmente, se estudió la efectividad de los tratamientosfisicoquímicos (temperatura, reducción de oxígeno atmosférico y uso de reactivos químicos) para la inhibición de la enzimaPolifenoloxidasa en el tubérculo. Los resultados mostraron que los tratamientos térmicos, sin uso de agentes químicos, fueronla mejor opción para la inhibición enzimática. La determinación de las curvas de secado de la pasta de papa, con tratamientoprevio, se llevó a cabo en un secador de túnel a 60 ºC y una velocidad de aire de 0.2 m/s. Los pre-tratamientos incluyeronescaldado, cocción y el uso de ácido ascórbico y metabisulfito de sodio. Los resultados indicaron que con la aplicación deltratamiento térmico al tubérculo fue suficiente para evitar el pardeamiento enzimático y además, se logra un menor tiempo desecado. Los datos experimentales fueron evaluados usando el modelo de Midilli observándose un buen ajuste con un R > 0.99.Además, se comprobó que el método más óptimo para la producción de harina de papa involucra las siguientes etapas: cocción,enfriamiento y reducción de tamaño en seco. Esto garantiza una harina, que según los resultados de poder de hinchamiento,solubilidad en agua y absorción de agua, alcanza las características de almidón instantáneo lo cual favorece la formación de unpuré de manera rápida. Los rendimientos en la producción de harina oscilan entre 12.55-14.09% para la Granola y entre11.18-15.58% para la provento en base húmeda.DOI: http://dx.doi.org/10.5377/nexo.v27i2.194

The role of hydrodynamics in structuring in situ ammonium uptake within a submerged macrophyte community

In low-nutrient, macrophyte-dominated coastal zones, benthic ammonium (NH4+) uptake may be influencedby the structural properties of plant canopies via their effect on near-bed hydrodynamics. Using adual-tracer (uranine and 15NH4+) method that does not require enclosures, we examined how this processaffects nutrient uptake rates within a tidally dominated, patchy Caulerpa prolifera–Cymodocea nodosalandscape. NH4+ uptake was determined by calculating tissue 15N excesses and correcting for 15N enrichmentas derived from uranine concentration. Vertical hydrodynamic profiles were measured in thedownstream flow direction from outside to inside of the C. nodosa bed by using an array of acousticDoppler velocimeters. The transition from a C. prolifera to a C. nodosa bed included a change in bothbenthic canopy properties (short and dense to tall and sparse) and sediment topography (0.2-m increasein water column depth) that resulted in an increase in longitudinal advection and turbulent diffusivitywithin the C. nodosa canopy between 0.5 and 1.5mfrom the leading edge. Vertical differences in canopywater exchange appeared to explain variations in uptake between biotic functional groups; however, noclear differences in longitudinal uptake were found. Using in situ labeling, this study demonstrated for thefirst time the role of hydrodynamics in structuring NH4+ uptake within an undisturbed, patchy macrophytelandscape

Comparative hydrochemical study in two sectors with abandoned metallic sulfide mines: Linares – La Carolina mining district (Jaén)

The Linares-La Carolina abandoned sulfide mines are partially flooded at present and the demand of water resources have led to the pumping of groundwater directly from the old shafts. There is a scarce mobilisation of heavy metals into the waters in the Linares area, which are characterized by net alkaline conditions (pH values from 6.7 to 8.2). Nevertheless, acid mine drainage is detected in La Carolina mining district, where pH values range from 3.4 to 7.3 and mine waters are characterized by a wide range of mineralization (from 300 mS/cm to 5500 mS/cm, approximately). In addition, Fe and Mn reach tens of mg/l, not only in acid mine drainage adits but also in some alkaline waters. These different hydrochemical types are interpreted as being due to the influence of the particular lithologies and hydrodynamic conditions of these mine

A novel retinoblastoma therapy from genomic and epigenetic analyses.

Retinoblastoma is an aggressive childhood cancer of the developing retina that is initiated by the biallelic loss of RB1. Tumours progress very quickly following RB1 inactivation but the underlying mechanism is not known. Here we show that the retinoblastoma genome is stable, but that multiple cancer pathways can be epigenetically deregulated. To identify the mutations that cooperate with RB1 loss, we performed whole-genome sequencing of retinoblastomas. The overall mutational rate was very low; RB1 was the only known cancer gene mutated. We then evaluated the role of RB1 in genome stability and considered non-genetic mechanisms of cancer pathway deregulation. For example, the proto-oncogene SYK is upregulated in retinoblastoma and is required for tumour cell survival. Targeting SYK with a small-molecule inhibitor induced retinoblastoma tumour cell death in vitro and in vivo. Thus, retinoblastomas may develop quickly as a result of the epigenetic deregulation of key cancer pathways as a direct or indirect result of RB1 loss

Contribution to the understanding of tribological properties of graphite intercalation compounds with metal chloride

Intrinsic tribological properties of lamellar compounds are usually attributed to the presence of van der Waals gaps in their structure through which interlayer interactions are weak. The controlled variation of the distances and interactions between graphene layers by intercalation of electrophilic species in graphite is used in order to explore more deeply the friction reduction properties of low-dimensional compounds. Three graphite intercalation compounds with antimony pentachloride, iron trichloride and aluminium trichloride are studied. Their tribological properties are correlated to their structural parameters, and the interlayer interactions are deduced from ab initio bands structure calculations