Fractionation and fluxes of metals and radionuclides during the recycling process of phosphogypsum wastes applied to mineral CO2 sequestration

The industry of phosphoric acid produces a calcium-rich by-product known as phosphogypsum, which is usually stored in large stacks of millions of tons. Up to now, no commercial application has been widely implemented for its reuse because of the significant presence of potentially toxic contaminants. This work confirmed that up to 96% of the calcium of phosphogypsum could be recycled for CO2 mineral sequestration by a simple two-step process: alkaline dissolution and aqueous carbonation, under ambient pressure and temperature. This CO2 sequestration process based on recycling phosphogypsum wastes would help to mitigate greenhouse gasses emissions. Yet this work goes beyond the validation of the sequestration procedure; it tracks the contaminants, such as trace metals or radionuclides, during the recycling process in the phosphogypsum. Thus, most of the contaminants were transferred from raw phosphogypsum to portlandite, obtained by dissolution of the phosphogypsum in soda, and from portlandite to calcite during aqueous carbonation. These findings provide valuable information for managing phosphogypsum wastes and designing potential technological applications of the by-products of this environmentally-friendly proposal.Junta de Andalucía P10-RNM-6300, P12- RNM-226

Bioactivity of wollastonite/aerogels composites obtained from a TEOS-MTES matrix

Organic-inorganic hybrid materials were synthesized by controlled hydrolysis of tetraethoxysilane (TEOS), methyltrimethoxysilane (MTES), synthetic wollastonite powders and polydimethylsiloxane (PDMS) in an ethanol solution. Aerogels were prepared from acid hydrolysis of TEOS and MTES with different volume ratio in ethanol, followed by addition of wollastonite powder and PDMS in order to obtain aerogels with 20 wt% of PDMS and 5 wt% of CaO of the total silica. Finally, when the wet gels were obtained, they were supercritically dried at 260°C and 90 bar, in ethanol. In order to obtain its bioactivity, one method for surface activation is based on a wet chemical alkaline treatment. The particular interest of this study is that we introduce hybrid aerogels, in a 1 M solution of NaOH, for 30 s at room temperature. We evaluate the bioactivity of TEOS-MTES aerogel when immersed in a static volume of simulated body fluid (SBF). An apatite layer of spherical-shaped particles of uniform size smaller than 5 microns is observed to form on the surface of the aerogels after 25 days soaking in SBF.Ministerio de Ciencia e Innovación MAT2005-01583Junta de Andalucía TEP 79

New method for carbon dioxide mineralization based on phosphogypsum and aluminium-rich industrial wastes resulting in valuable carbonated by-products

A new carbon mineralization method was designed based on a sequestration agent synthesised exclusively from industrial wastes. Phosphogypsum waste from the fertiliser industry was dissolved into caustic aqueous waste from the aluminium anodising industry. The resulting precipitate consisted of katoite (Ca3Al2(OH)12, a Si-free hydrogrossular solid solution end-member of the Al-containing hydrogarnet) and thenardite (Na2SO4); the latter easily removed by rinsing with water. The carbonation performance of this katoite-rich sequestration agent was evaluated using two different methods, by bubbling in aqueous media and by weathering. Both procedures yielded high carbonation efficiencies (80% and 100%, respectively), and resulted in a solid precipitate composed primarily of calcite (CaCO3) and aluminium hydroxide (Al(OH)3). Priority attention was given to the transfer of trace elements and radionuclides of the uranium series typically present in the phosphogypsum. Results confirmed that the traces were transferred to resulting final solid carbonate at concentrations similar to those present in the raw phosphogypsum. In conclusion, these carbonated minerals would trap substantial amounts of CO2 and produce final materials with similar civil engineering uses to those proposed for current phosphogypsum wastes. This work offers new methods for jointly managing specific industrial wastes oriented to more sustainable industrial processes and controlling CO2 emissionsGobierno de España MAT2013-42934- RJunta de Andalucía P12-RNM-226

Clinician ratings of the Comprehensive Assessment of Psychopathic Personality (CAPP) in a representative sample of Spanish prison inmates: New validity evidence

The Comprehensive Assessment of Psychopathic Personality (CAPP) is a concept map of psychopathic personality disorder (PPD). The CAPP- Institutional Rating Scale (IRS) is a tool designed to assess CAPP symptoms in institutional settings. The CAPP contains 33 personality traits organized in six domains: attachment, behavioural, cognitive, dominance, emotional and self. Until now, much of the CAPP research has been conducted out of clinical, forensic and correctional settings using self-ratings. In the current study, the psychometric properties and construct validity of the CAPP-IRS were evaluated in a non-convenience sample of 204 Spanish convicts. Clinician ratings were employed. Participants had been imprisoned for at least 6 months at Pereiro de Aguiar Penitentiary. This group of inmates was heterogeneous with respect to type of official charges, and representative as all convicts interned for at least 6 months in this prison were screened for participation. Classical test theory indexes of reliability, correlations between CAPP items and domains and external correlations and structural analyses demonstrated that CAPP assessment is a solid and robust way of evaluating psychopathy in a correctional setting. Best fit was found for a three-factor model: attachment and emotional items associated with a callous and unemotional trait, dominance and self items associated with a pathological interpersonal style, and behavioural and residual items from other domains associated with impulsivity

Efecto de la aplicación del ácido giberélico sobre el crecimiento de coliflor (Brassica oleraceae L.) var. Botrytis DC.

La coliflor es una de las hortalizas de mayor consumo en Colombia, es muy apetecida comercialmente por sus aportes nutricionales y por ello su mercado se ha ampliado a congelados y procesados con fines de exportación. Con el propósito de determinar el efecto del ácido giberélico (AG3) sobre el crecimiento de órganos cosechados se realizó un experimento en dos épocas de siembra en los que se aplicaron concentraciones de 0, 5, 25 y 125 mg· L-1 de AG3. Se cuantificaron variables como la masa seca total, la masa seca por órganos (raíz, tallo e inflorescencia), el número de flores y la altura de planta. Los resultados demostraron que la dosis de 25 mg·L-1 de AG3 fue la más apropiada para inducir la floración y obtener mayor altura de planta, mientras que la dosis de 5 mg· L-1 de AG3 permitió acumular mayor cantidad e biomasaColiflor-Brassica olerace

Social Skills and Psychological Disorders: Converging and Criterion-Related Validity for YSR and IHSA-Del-Prette in Adolescents at Risk

This study evaluated indexes of converging and criterion-related validity for the Social Skills Inventory for Adolescents (IHSA-Del-Prette) and the Youth Self-Report (YSR) in two samples: one referring to clinical service (CLIN), with 28 adolescents (64.3% boys), 11 through 17 years old (M = 13.75; SD = 1.74), and the other referring to a psycho-educational program (PME = 46.2%), mainly composed of boys (91.7%) aged 13 through 17 (M = 15.33; SD = 1.47). Both samples completed the two inventories. Results showed a high incidence of psychological disorders in both samples (between 4% and 79% in the borderline or clinical range on YSR scales) and accentuated deficits in the general and subscale scores of IHSA-Del-Prette, especially on the frequency scale (25% to 58%). The correlations between the instruments in the two groups supported criterion-related and converging validity. Some issues concerning the differences between the samples and about the construct of social competence, underlying these inventories, are discussed. Key words authors

Aerogeles con aplicaciones en biomedicina y medioambiente

Es posible preparar materiales híbridos inorgánico-orgánicos incorporando una fase orgánica sobre un sol obtenido por hidrólisis de metalorgánico mientras se aplican ultrasonidos de alta potencia. Cuando las dos fases quedan químicamente enlazadas resulta un sono-ormosil (de ORganic MOdified SILicate) conocido también como ormosil duro. Unas de las aplicaciones de estos materiales atañe el dominio de la biotecnología pues llegan a ser bioactivos cuando contienen Ca, cumpliendo con ello el primer requisito para su validez como implantes óseos. La fuente de calcio, seleccionada para optimizar el proceso de secado supercrítico en etanol, ha sido partículas de wollastonita, (CaSiO3), material bioactivo, lo que al influir sobre el volumen poroso y el radio de los poros, permite controlar la densidad y situar la resistencia mecánica en el intervalo de valores propios de los huesos humanos esponjosos. Por otra parte, los poros pueden hacerse químicamente activos y usarse como soportes estructurales para la captación y fijación de gases.It is possible to synthesise inorganic-organic hybrid materials incorporating the organic phase to a sol prepared from a metal organic under high power ultrasounds. When both phases are chemically bonded a sono-ormosil (from ORganic MOdified SILicate) results, also known as hard ormosil. One of the applications of these materials concerns the biotechnologies since they become bioactive when are doped with Ca, fulfilling this way the preliminary condition to be considered for bone implants. The addition of silicate particles allows modifying the pore volume and radius. We have used these gels with particles, as precursor of the bioactive component, in order to act on the porosity for controlling the density and adequate the mechanical strength to that of the human cancellous bone. In like manner, the pores becomes chemically active and be used as structural support for noxious atmospheric gas sequestration

Contribution of teaching in metacognitive processes and the resolution of mathematical problems

The present study evaluates the contribution of teaching from problem solving to metacognitive processes (Analysis, Planning, Local Monitoring and Global Monitoring) problem solving. The sample consisted of 41 second grade students from a public school in the department of Atlántico (Colombia). Observation was used as the main technique through video recordings of the classes, in addition the Teaching Practice Observation Format and a Semistructured Flexible Interview were used. The participants were selected by means of a nonprobabilistic sampling of intentional type. Regarding the results, the average scores in the metacognitive processes were examined, as well as their relationship at the bivariate level (Pearson's correlation) with the success in solving quantitative reasoning problems. Finally, the predictive variables of success were examined and 43.7% of the Local Monitoring variance was explained by practice at the Start of class and 39.4% of the Global Monitoring variance was explained by practice at Class Closing. . The results obtained in relation to the practice in the classroom are discussed and a series of final recommendations are suggested that contribute to the success in solving mathematical problems to make decisions directed towards the improvement of the curricular processes.El presente estudio evalúa la contribución de la enseñanza desde la resolución de problemas a los procesos Metacognitivos (Análisis, Planeación, Monitoreo Local y Monitoreo Global) de resolución de problemas. La muestra estuvo conformada por 41 estudiantes de segundo grado de un colegio público del departamento del Atlántico (Colombia). Se empleó la observación como técnica principal mediante videograbaciones de las clases, además se empleó el Formato de Observación de la Práctica Docente y se hizo una Entrevista Flexible Semiestructurada. Los participantes fueron seleccionados mediante un muestreo no probabilístico de tipo intencional. Respecto a los resultados, se examinaron las puntuaciones medias en los procesos Metacognitivos, así como su relación a nivel bivariado (correlación de Pearson) con el éxito en la resolución de problemas de razonamiento cuantitativo. Finalmente, se examinaron las variables predictoras del éxito y se comprobó el 43.7% de la varianza de Monitoreo Local fue explicada por la práctica al Inicio de clase y el 39.4% de la varianza de Monitoreo Global fue explicada por la práctica al Cierre de la Clase. Se discuten los resultados obtenidos en relación con la práctica en el aula y se sugiere una serie de recomendaciones finales que contribuyan al éxito en resolución de problemas matemáticos para tomar decisiones direccionadas hacia el mejoramiento de los procesos curriculares

Efecto combinado de grafeno y nanotubos de carbono en las propiedades de las resinas dopadas

En este trabajo se estudia la eficiencia de la adición de nanorrefuerzos grafíticos para la mejora de las propiedades de resinas epoxídicas. Para ello, se han obtenido dispersiones de nanotubos de carbono y nanoplaquetas de grafeno en resinas termoestables de calidad aeronáutica. Se ha confirmado que la adición de bajos contenidos de nanotubos aumenta la temperatura de transición vítrea de las resinas y su conductividad eléctrica, mientras que el grafeno aporta un interesante aumento de la conductividad térmica. Es por ello que se concluye que ambos refuerzos son complementarios e inducen mejoras del material en diferentes propiedades

Overexpression of Dyrk1A Is Implicated in Several Cognitive, Electrophysiological and Neuromorphological Alterations Found in a Mouse Model of Down Syndrome

Down syndrome (DS) phenotypes result from the overexpression of several dosage-sensitive genes. The DYRK1A (dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A) gene, which has been implicated in the behavioral and neuronal alterations that are characteristic of DS, plays a role in neuronal progenitor proliferation, neuronal differentiation and long-term potentiation (LTP) mechanisms that contribute to the cognitive deficits found in DS. The purpose of this study was to evaluate the effect of Dyrk1A overexpression on the behavioral and cognitive alterations in the Ts65Dn (TS) mouse model, which is the most commonly utilized mouse model of DS, as well as on several neuromorphological and electrophysiological properties proposed to underlie these deficits. In this study, we analyzed the phenotypic differences in the progeny obtained from crosses of TS females and heterozygous Dyrk1A (+/-) male mice. Our results revealed that normalization of the Dyrk1A copy number in TS mice improved working and reference memory based on the Morris water maze and contextual conditioning based on the fear conditioning test and rescued hippocampal LTP. Concomitant with these functional improvements, normalization of the Dyrk1A expression level in TS mice restored the proliferation and differentiation of hippocampal cells in the adult dentate gyrus (DG) and the density of GABAergic and glutamatergic synapse markers in the molecular layer of the hippocampus. However, normalization of the Dyrk1A gene dosage did not affect other structural (e.g., the density of mature hippocampal granule cells, the DG volume and the subgranular zone area) or behavioral (i.e., hyperactivity/attention) alterations found in the TS mouse. These results suggest that Dyrk1A overexpression is involved in some of the cognitive, electrophysiological and neuromorphological alterations, but not in the structural alterations found in DS, and suggest that pharmacological strategies targeting this gene may improve the treatment of DS-associated learning disabilities