Estudio de la visión martiana del catastrofismo. Una mirada desde la educación ambiental / Study of Marti's vision of catastrophism. A look from the environmental education

El presente artículo tiene como objetivo constatar las potencialidades que brinda la obra martiana para lograr un desempeño profesional pedagógico ambiental en los profesores, a partir de las descripciones realizadas por Martí sobre catástrofes naturales o provocadas por la acción del hombre. Para la realización de esta tarea se usan los métodos del nivel teórico como el analítico-sintético y el inductivo-deductivo en la interpretación de la visión martiana sobre las catástrofes. Se ofrecen sugerencias para la introducción de una nueva temática nombrada “Visión martiana del catastrofismo. Una mirada hacia la educación ambiental” en el programa de la asignatura “Ética e Ideario Martiano”.The aim of this paper is to ascertain the potential offered by Marti's work to achieve an environmental, educational and professional development on teachers from descriptions by Martí on natural disasters by human action. To perform this task theoretical and analytic-synthetic and inductive-deductive methods were used in the interpretation of Marti's vision of disaster. Suggestions for the introduction of a new vision of Marti on catastrophe. This work is look at the environmental education program of the subject Ethics and Marti Ideology

Bis(hydrosulfido)-bridged dinuclear rhodium(I) complexes as a platform for the synthesis of trinuclear sulfido aggregates with the core [MRh2(μ3-S2)] (M = Rh, Ir, Pd, Pt, Ru)

The reaction of [Rh(μ-SH)(CO)(PPh3)]2 or [Rh(μ-SH){P(OPh)3}2]2 with [Cp*MCl2]2 (M = Rh, Ir) in the presence of NEt3 afforded the Rh3 and IrRh2 sulfido-bridged compounds [Cp*M(μ3-S)2Rh2(CO)2(PPh3)2] (M = Rh, 1; Ir, 2) and [Cp*Rh(μ3-S)2Rh2{P(OPh)3}4] (3). The reaction with [MCl2(cod)] (M = Pd, Pt), cis-[PtCl2(PPh3)2] or [(η6-C6H6)RuCl2]2 under the same experimental conditions gave [(cod)M(μ3-S)2Rh2{P(OPh)3}4] (M = Pd, 6; Pt, 7), [(cod)M(μ3-S)2Rh2(CO)2(PPh3)2] (M = Pd, 8; Pt, 9), [(PPh3)2Pt(μ3-S)2Rh2(CO)2(PPh3)2] (10) and [(η6-C6H6)Ru(μ3-S)2Rh2(CO)2(PPh3)2] (12), with PdRh2, PtRh2 and RuRh2 trimetallic cores. The aggregates derived from [Rh(μ-SH)(CO)(PPh3)]2 were isolated as a mixture of trans and cis isomers in which the trans isomer predominates. The reaction of [Rh(μ-SH){P(OPh)3}2]2 with 2 equiv. of n-BuLi at 253 K followed by addition of [Cp*IrCl2]2 gave [Cp*Ir(μ3-S)2Rh2{P(OPh)3}4] (4) and [Cp*2ClIr2(μ3-S)2Rh{P(OPh)3}2] (5) in a 3:2 ratio. The RuRh2 compound [(η6-C6H6)Ru(μ3-S)2Rh2{P(OPh)3}4] (11) was prepared similarly from [Rh(μ-SH){P(OPh)3}2]2 and [(η6-C6H6)RuCl2]2 using n-BuLi as a deprotonating agent. The molecular structures of compounds 3, 6, 7, 9 and 11 have been determined by X-ray analysis. The trinuclear complexes exhibit an asymmetric triangular metal core with two triply bridging sulfido ligands resulting in a distorted trigonal-bipyramidal M3(μ3-S)2 heterometallic metal–sulfur core.Financial support from the Ministerio de Ciencia e Innovación (MICINN/FEDER) of Spain (Project CTQ2010-15221), the Diputación General de Aragón (E07), and CONSOLIDER INGENIO-2010, Projects MULTICAT (CSD2009-00050) and Factoría de Cristalización (CSD2006-0015) is gratefully acknowledged.Peer Reviewe

Overoxidation of chloroplast 2-Cys peroxiredoxins: balancing toxic and signaling activities of hydrogen peroxide

Photosynthesis, the primary source of biomass and oxygen into the biosphere, involves the transport of electrons in the presence of oxygen and, therefore, chloroplasts constitute an important source of reactive oxygen species, including hydrogen peroxide. If accumulated at high level, hydrogen peroxide may exert a toxic effect; however, it is as well an important second messenger. In order to balance the toxic and signaling activities of hydrogen peroxide its level has to be tightly controlled. To this end, chloroplasts are equipped with different antioxidant systems such as 2-Cys peroxiredoxins (2-Cys Prxs), thiol-based peroxidases able to reduce hydrogen and organic peroxides. At high peroxide concentrations the peroxidase function of 2-Cys Prxs may become inactivated through a process of overoxidation. This inactivation has been proposed to explain the signaling function of hydrogen peroxide in eukaryotes, whereas in prokaryotes, the 2-Cys Prxs of which were considered to be insensitive to overoxidation, the signaling activity of hydrogen peroxide is less relevant. Here we discuss the current knowledge about the mechanisms controlling 2-Cys Prx overoxidation in chloroplasts, organelles with an important signaling function in plants. Given the prokaryotic origin of chloroplasts, we discuss the occurrence of 2-Cys Prx overoxidation in cyanobacteria with the aim of identifying similarities between chloroplasts and their ancestors regarding their response to hydrogen peroxide.España , Ministerio de Ciencia e Innovación BIO2010-15430España, Junta de Andalucía BIO-182España, Junta de Andalucía CVI-591

Hiponatremia en pacientes neurocríticos en la unidad de cuidados intensivos

Introducción: La hiponatremia es el trastorno electrolítico más frecuente en la práctica clínica. El cerebro es el principal órgano diana en relación a la morbilidad producida por esta afección, debido a la rigidez del cráneo, lo que impide su adaptación en situaciones de edema cerebral. Objetivo: Caracterizar a los pacientes neurocríticos con hiponatremia ingresados en la Unidad de Cuidados Intensivos del Hospital Universitario "General Calixto García".Métodos: Se realizó un estudio observacional, descriptivo y longitudinal. El universo estuvo constituido por 84 pacientes que ingresaron con lesiones neurológicas agudas y la muestra quedó conformada por 28 pacientes con disminución del sodio sérico. Se excluyeron aquellos pacientes cuya estadía en la terapia intensiva fue menor de 24 horas, y aquellos que no dieron su consentimiento para participar en la investigación. Las principales variables estudiadas fueron el grado de severidad de la hiponatremia, motivo de ingreso, estado al egreso, estado de la volemia y días de ventilación mecánica.Resultados: Hubo un predominio de pacientes del sexo masculino. La edad promedio fue 45,9 años. El 28,6 % de la muestra tuvo lesiones traumáticas. La mortalidad se incrementó en pacientes con hiponatremia severa. La ventilación mecánica tuvo una duración mayor de 10 días.Conclusiones: La hiponatremia se presentó con mayor frecuencia en pacientes con trauma craneoencefálico, y estuvo asociada a un peor pronóstico según se incrementó la severidad de esta

Genetic Heterogeneity Underlying Phenotypes with Early-Onset Cerebellar Atrophy

Cerebellar atrophy (CA) is a frequent neuroimaging finding in paediatric neurology, usually associated with cerebellar ataxia. The list of genes involved in hereditary forms of CA is continuously growing and reveals its genetic complexity. We investigated ten cases with early-onset cerebellar involvement with and without ataxia by exome sequencing or by a targeted panel with 363 genes involved in ataxia or spastic paraplegia. Novel variants were investigated by in silico or experimental approaches. Seven probands carry causative variants in well-known genes associated with CA or cerebellar hypoplasia: SETX, CACNA1G, CACNA1A, CLN6, CPLANE1, and TBCD. The remaining three cases deserve special attention; they harbour variants in MAST1, PI4KA and CLK2 genes. MAST1 is responsible for an ultrarare condition characterised by global developmental delay and cognitive decline; our index case added ataxia to the list of concomitant associated symptoms. PIK4A is mainly related to hypomyelinating leukodystrophy; our proband presented with pure spastic paraplegia and normal intellectual capacity. Finally, in a patient who suffers from mild ataxia with oculomotor apraxia, the de novo novel CLK2 c.1120T>C variant was found. The protein expression of the mutated protein was reduced, which may indicate instability that would affect its kinase activity

Direct Access to 2,3,4,6-Tetrasubstituted Tetrahydro-2H-pyrans via Tandem SN2'-Prins Cyclization

A new direct and diastereoselective synthesis of activated 2,3,4,6-tetrasubstituted tetrahydro-2H-pyrans is described. In this reaction iron(III) catalyzed an SN2’-Prins cyclization tandem process leading to the creation of three new stereocenters in one single step. These activated tetrahydro-2H-pyran units are easily derivatizable through CuAAC conjugations in order to generate multi-functionalized complex molecules. DFT calculations support the in situ SN2’ reaction as a preliminary step in the Prins cyclizatio

Cholesterol Enhances the Toxic Effect of Ethanol and Acetaldehyde in Primary Mouse Hepatocytes

Obesity and alcohol consumption are risk factors for hepatic steatosis, and both commonly coexist. Our objective was to evaluate the effect of ethanol and acetaldehyde on primary hepatocytes obtained from mice fed for two days with a high cholesterol (HC) diet. HC hepatocytes increased lipid and cholesterol content. HC diet sensitized hepatocytes to the toxic effect of ethanol and acetaldehyde. Cyp2E1 content increased with HC diet, as well as in those treated with ethanol or acetaldehyde, while the activity of this enzyme determined in microsomes increased in the HC and in all ethanol treated hepatocytes, HC and CW. Oxidized proteins were increased in the HC cultures treated or not with the toxins. Transmission electron microscopy showed endoplasmic reticulum (ER) stress and megamitochondria in hepatocytes treated with ethanol as in HC and the ethanol HC treated hepatocytes. ER stress determined by PERK content was increased in ethanol treated hepatocytes from HC mice and CW. Nuclear translocation of ATF6 was observed in HC hepatocytes treated with ethanol, results that indicate that lipids overload and ethanol treatment favor ER stress. Oxidative stress, ER stress, and mitochondrial damage underlie potential mechanisms for increased damage in steatotic hepatocyte treated with ethanol

Self-esteem and suicidal behaviour in youth: A meta-analysis of longitudinal studies

Background: Previous literature suggests that low self-esteem is a risk factor for suicide attempts, but no meta-analyses have been conducted to assess this association in adolescents/young adults. The present study examined the relationship between low self-esteem and suicide attempts in young people (12-26 years old). Method: Meta-analyses were performed using random-effects models (ES) and odds ratio (OR). Heterogeneity and sensitivity analyses were performed. Results: From 26,883 initial titles, 22 studies met the inclusion criteria, of which 9 studies had data that could be included in the meta-analysis. The meta-analysis showed that youths with lower self-esteem were more likely to have future suicide attempts, with an effect size (self-esteem as continuous variable) of d = .58 (95% CI = .44 - .73) and, for low self-esteem (categorical variable) an OR = 1.99 (95% CI = 1.39-2.86; p < .001). Conclusion: A low level of self-esteem is a risk factor for suicide attempts in adolescents/young adults

Metodologías y experiencias de investigación en comunicación e información

This work contextualizes the state of research in the areas of Communication Sciences and Information Sciences and presents new national and international methodological experiences that allow enriching the research experience of groups and lines of research developed in both thematic areas. The intersections between qualitative and quantitative methodologies, cases and ways of approaching research are explored, and new knowledge is provided both from studying the context of the situation and from the actual practices that allow opening doors and consolidating research in emerging areas, such as communication and information. The knowledge transfer carried out in this work is the result of the research work of consolidated research groups that carry out their research financed by public and private bodies of the first order and that are developed in Higher Education centres. The result is a volume directed at researchers and carried out by researchers who are looking for the intersection and collaboration in experiences that may allow the enrichment and progress of investigation