The effect of sepiolite on the compatibilization of polyethylene thermoplastic starch blends for environmentally friendly films

The final publication is available at Springer via http://dx.doi.org/10.1007/s10853-014-8647-8[EN] Green polyethylene is a new and attracting polymer from biobased resources (sugarcane) and identical properties to petroleum-based polyethylene. Its potential in the packaging industry is really promising. In this work, we report the use of different compatibilizer systems for green polyethylene (from sugarcane) and thermoplastic starch (30 wt% TPS) in order to increase ductile mechanical properties and biodegradable content. Typical petroleum-based graft copolymer of polyethylene with maleic anhydride (PE-g-MA) is used as reference compatibilizer, and new compatibilizer systems are developed using sepiolite. The obtained results show that sepiolite-based compatibilizers provide good compatibilization properties as observed by a remarkable increase in elongation at break and a noticeable size reduction of the TPS domains dispersed in the green polyethylene matrix as observed by scanning electron microscopy (SEM).This study has been funded by the ‘‘Conselleria d’Educacio´, Cultura i Esport’’—Generalitat Valenciana (Reference number: GV/2014/008). Authors thank Tolsa S.A for kindly supply sepiolite for this study and Microscopy Services at UPV for helping in using SEM and TEM techniques.Samper Madrigal, MD.; Fenollar Gimeno, OÁ.; Dominici, F.; Balart Gimeno, RA.; Kenny, JM. (2015). The effect of sepiolite on the compatibilization of polyethylene thermoplastic starch blends for environmentally friendly films. 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Análisis de la evolución de las familias acogedoras y los factores personales que favorecen los acogimientos

El acogimiento familiar es un recurso de protección del menor donde familias de forma voluntaria acogen a menores que por diversas circunstancias no pueden ser atendidos por sus familias. Para ello las distintas administraciones con competencia programan la formación y la valoración necesaria para otorgar a estas familias la idoneidad para la realización de acogimientos. A partir de ese momento, la familia espera la asignación de un menor en función de sus características y disponibilidad, así como del perfil del menor y sus necesidades. En la presente comunicación se analiza la evolución de un grupo de familias acogedoras a lo largo de tres años y las características personales de los acogedores que resultaron más adecuadas para llevar a cabo acogimientos exitosos. La valoración del ajuste de las familias acogedoras fue realizada por el equipo de técnicos que efectuaba el seguimiento y apoyo especializado de los acogimientos. Además se recogieron datos de personalidad y estilo educativo. Los factores de buen ajuste que destacaron fueron el estilo educativo democrático-asertivo, así como entre las características de personalidad la estabilidad emocional, la energía y la afabilidad.Foster care is a resource for protecting minors by which families voluntarily decide to foster minors that due to several reasons cannot be taken care of by their families. For that, the corresponding organizations with cognizant of the subject, draw up a plan of the training and assessment needed by the families to be considered suitable to take in children. From this moment on, the family has to wait to be assigned a minor depending on their characteristics and availability, as well as on the minor´s profile and needs. In this communication we analyse the evolution of a group of foster families throughout three years as well as the features of the foster families that ended up being more suitable for successful foster adoptions. The assessment of the suitability of the foster families was made by the team of trainers that were in charge of the specialised monitoring and support of the foster care adoption. In addition, further data on personality and educational style were collected. The proper adjustment features that stood out were the democratic assertive educational style and from the personality and emotional stability features, energy and affability

Synthesis, Photochemical, and Redox Properties of Gold(I) and Gold(III) Pincer Complexes Incorporating a 2,2′:6′,2″-Terpyridine Ligand Framework

Reaction of [Au(C6F5)(tht)] (tht = tetrahydrothiophene) with 2,2′:6′,2″-terpyridine (terpy) leads to complex [Au(C6F5)(η1-terpy)] (1). The chemical oxidation of complex (1) with 2 equiv of [N(C6H4Br-4)3](PF6) or using electrosynthetic techniques affords the Au(III) complex [Au(C6F5)(η3-terpy)](PF6)2 (2). The X-ray diffraction study of complex 2 reveals that the terpyridine acts as tridentate chelate ligand, which leads to a slightly distorted square-planar geometry. Complex 1 displays fluorescence in the solid state at 77 K due to a metal (gold) to ligand (terpy) charge transfer transition, whereas complex 2 displays fluorescence in acetonitrile due to excimer or exciplex formation. Time-dependent density functional theory calculations match the experimental absorption spectra of the synthesized complexes. In order to further probe the frontier orbitals of both complexes and study their redox behavior, each compound was separately characterized using cyclic voltammetry. The bulk electrolysis of a solution of complex 1 was analyzed by spectroscopic methods confirming the electrochemical synthesis of complex 2

Geothermometrical modelling applied to the CO2-rich thermal waters of the Lanjarón hydrothermal system (Granada, Spain)

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Estudio de la densidad mineral ósea mediante osteosonografía en niños y adolescentes sanos: valores de normalidad

Osteoporosis is a frequent health problem in adults. Optimization of bone mass acquisition during childhood and adolescence may play a major role in the prevention of this disease. Osteosonography is a recent technique for measuring bone mineralization without exposing the patient to radiation. OBJECTIVES: To measure bone mineral density using osteosonography in healthy Spanish Caucasian children and adolescents in order to determine normal values. METHODS: We performed a cross sectional study of 829 healthy child and adolescent volunteers (360 girls and 469 boys) randomly selected from the urban area of Pamplona in Navarre (Spain). Ages ranged from 6 to 18 years. ADBM Sonic 1200 ultrasound densitometer from IGEA was used. Daily calcium dietary intake and amount of physical activity were recorded. RESULTS: Cross sectional standards for Ad-SOS are presented. Ad-SOS did not significantly change between the ages of 6 and 9 years in girls or until the age of 10 years in boys. From the ages of 10 to 14 years, Ad-SOS values were higher in girls than in boys. After the age of 14 years, no significant differences were found. No correlation was found between calcium dietary intake, amount of physical exercise or bone mineralization values. CONCLUSIONS: Measurement of Ad-SOS by osteosonography is an easy, fast and inexpensive method for measuring bone mineral density in children and adolescents without exposing them to radiation. It can be used in the pediatric population to detect early alterations in bone mineralization

Application of chemical geothermometers to a low temperature thermal system

The Tiermas geothermal system is one of the areas with the greatest geothermal potential in Aragón, however, its hydrogeological and geochemical features are still poorly known. In this study, the main hydrochemical features of these waters are presented and the reservoir temperature is approached by applying chemical geothermometers. These waters have a sulphate chloride sodium affinity, with nearly 40 ºC of spring temperature and an approximate flow rate of 200 l/s. The most likely aquifer seems to be located in the Paleocene and Eocene carbonates. However, due to the structural complexity of the area, the waters would also interact with the evaporitic facies present in the Eocene–Oligocene boundary. Two different hydrochemical groups have been distinguished based on their salinity, Na/Cl ratios, SO4 concentrations and TDS values. Despite the compositional variations detected in the springs, the geothermometric calculations allow to infer a reservoir temperature of 85 ± 17 °C. Good consistency has been obtained with the cationic geothermometers, which is an unusual situation for a geothermal system in carbonate–evaporitic materialsEl sistema geotermal de Tiermas representa una de las zonas con mayor potencial geotérmico de Aragón y, sin embargo, se sabe todavía poco acerca de sus características hidrológicas y geoquímicas. En este trabajo se presentan los principales rasgos hidroquímicos de estas aguas y se determina su temperatura en profundidad mediante la aplicación de geotermómetros químicos. Estas aguas tienen una afinidad clorurada sulfatada sódica, una temperatura de surgencia de casi 40 °C y un caudal de unos 200 l/s. El acuífero más probable se localizaría en los carbonatos del Paleoceno y Eoceno, pero debido a la complejidad estructural de la zona, las aguas entrarían en contacto con la facies evaporítica del tránsito Eoceno–Oligoceno, adquiriendo así dicha afinidad. Se han distinguido dos grupos hidroquímicos con una diferente salinidad, relación Na/Cl y concentraciones de SO4 y TSD. A pesar de las variaciones composicionales detectadas en las surgencias, los cálculos geotermométricos realizados permiten establecer un rango de temperaturas en el reservorio de 85 ± 17 °C, habiéndose obtenido buenos resultados con los geotermómetros catiónicos, situación poco habitual en sistemas termales instalados en materiales carbonatados – evaporítico

Mineral equilibria and thermodynamic uncertainties in the geothermometrical characterisation of carbonate geothermal systems of low temperature. The case of the Alhama-Jaraba system (Spain)

Geothermometrical characterisation of low-temperature, carbonate-evaporitic geothermal systems is usually hampered by the lack of appropriate mineral equilibria to successfully use most of the classical geothermometers and/or by the thermodynamic uncertainties affecting some of the most probable mineral equilibria in low temperature conditions. This situation is further hindered if the thermal waters are additionally affected by secondary processes (e.g., CO2 loss) during their ascent to surface. All these problems cluster together in the low-temperature Alhama-Jaraba thermal system, hosted in carbonate rocks, with spring temperatures about 30 °C and waters of Ca-Mg−HCO3/SO4 type. This system, one of the largest naturally flowing (600 L/s) low temperature thermal systems in Europe, is used in this paper as a suitable frame to assess the problems in the application of chemical geothermometrical techniques (classical geothermometers and geothermometrical modelling) and to provide a methodology that could be used in this type of geothermal system or in potential CO2 storage sites in similar aquifers. The results obtained have shown that the effects of the secondary processes can be avoided by selecting the samples unaffected by such processes and, therefore, representative of the conditions at depth, or by applying existing methodologies to reconstruct the original composition, as is usually done for medium to high temperature systems. The effective mineral equilibria at depth depend on the temperature, the residence time and the specific lithological/mineralogical characteristics of the system studied. In the present case, the mineral equilibria on which classical cation geothermometers are based have not been attained. The low proportion of evaporitic minerals in the hosting aquifer prevents the system from reaching anhydrite equilibrium, otherwise common in carbonate-evaporitic systems and necessary for the specific SO4-F geothermometer or the specially reliable quartz (or chalcedony) – anhydrite equilibrium in the geothermometrical modelling of these geothermal systems. Under these circumstances, the temperature estimation must rely on quartz (or chalcedony), clay minerals and, especially, calcite and dolomite. However, clay minerals and dolomite present important thermodynamic uncertainties related to possible variations in composition or crystallinity degree for clays and order/disorder degree for dolomite. To deal with these problems, a sensitivity analysis to the thermodynamic data for clay minerals has been carried out, comparing the results obtained when considering different solubility data. The uncertainties associated with dolomite have been addressed by reviewing the solubility data available for dolomites with different order degrees and performing specific calculations for the order degree of the dolomite in the aquifer. This approach can be used to find the most adequate dolomite thermodynamic data for the system under consideration, including medium-high temperature geothermal systems. Finally, the temperature estimation of the Alhama-Jaraba waters in the deep reservoir has been obtained from simultaneous equilibria of quartz, calcite, partially disordered dolomite and some aluminosilicate phases. The obtained value of 51 ± 14 °C is within the uncertainty range normally affecting this type of estimations and is coherent with independent estimations from geophysical data

Morphology and histology of the uropygial gland in Antarctic birds: relationship with their contact with the aquatic environment?

Fil: Chiale, María Cecilia. División Zoología Vertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; ArgentinaFil: Fernández, Patricia E.. Cátedra de Patología Genera. Facultad de Ciencias Veterinarias. Universidad Nacional de La Plata; ArgentinaFil: Gimeno, Eduardo J.. Cátedra de Patología General. Facultad de Ciencias Veterinarias. Universidad Nacional de La Plata; ArgentinaFil: Barbeito, Claudio G.. Cátedra de Histología y Embriología. Facultad de Ciencias Veterinarias. Universidad Nacional de La Plata; ArgentinaFil: Montalti, Diego. División Zoología Vertebrados. Facultad de Ciencias Naturales y Museo. Universidad Nacional de La Plata; Argentin

Depth of focus increase by multiplexing programmable diffractive lenses

A combination of several diffractive lenses written onto a single programmable liquid crystal display (LCD) is proposed for increasing the Depth of Focus (DOF) of the imaging system as a whole. The lenses are spatially multiplexed in a random scheme onto the LCD. The axial irradiance distribution produced by each lens overlaps with the next one producing an extended focal depth. To compare the image quality of the multiplexed lenses, the Modulation Transfer Function (MTF) is calculated. Finally we obtain the experimental Point Spread Functions (PSF) for these multiplexed lenses and experimental results in which an extended object is illuminated under spatially incoherent monochromatic light. We compare the images obtained in the focal plane and in some defocused planes with the single lens and with three multiplexed lenses. The experimental results confirm that the multiplexed lenses produce a high increase in the depth of focus.Fil: Iemmi, Claudio Cesar. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Campos, Juan. Universitat Autonoma de Barcelona; EspañaFil: Escalera, J. C.. Universitat Autonoma de Barcelona; EspañaFil: López Coronado, O. Universitat Autonoma de Barcelona; EspañaFil: Gimeno, R.. Universitat Autonoma de Barcelona; EspañaFil: Yzuel, María J.. Universitat Autonoma de Barcelona; Españ

Molecular characterization and heterologous expression of a Xanthophyllomyces dendrorhous ¿-glucosidase with potential for prebiotics production

Abstract Basidiomycetous yeast Xanthophyllomyces dendrorhous expresses an α-glucosidase with strong transglycosylation activity producing prebiotic sugars such as panose and an unusual tetrasaccharides mixture including α–(1–6) bonds as major products, which makes it of biotechnological interest. Initial analysis pointed to a homodimeric protein of 60 kDa subunit as responsible for this activity. In this study, the gene Xd-AlphaGlu was characterized. The 4131-bp-long gene is interrupted by 13 short introns and encodes a protein of 990 amino acids (Xd-AlphaGlu). The N-terminal sequence of the previously detected 60 kDa protein resides in this larger protein at residues 583–602. Functionality of the gene was proved in Saccharomyces cerevisiae, which produced a protein of about 130 kDa containing Xd-AlphaGlu sequences. All properties of the heterologously expressed protein, including thermal and pH profiles, activity on different substrates, and ability to produce prebiotic sugars were similar to that of the α-glucosidase produced in X. dendrorhous. No activity was detected in S. cerevisiae containing exclusively the 1256-bp from gene Xd-AlphaGlu that would encode synthesis of the 60 kDa protein previously detected. Data were compatible with an active monomeric α-glucosidase of 990 amino acids and an inactive hydrolysis product of 60 kDa. Protein Xd-AlphaGlu contained most of the elements characteristic of α-glucosidases included in the glycoside hydrolases family GH31 and its structural model based on the homologous human maltase-lucoamylase was obtained. Remarkably, the Xd-AlphaGlu C-terminal domain presents an unusually long 115-residue insertion that could be involved in this enzyme’s activity against long-size substrates such as maltoheptaose and soluble starch.Spanish Ministry of Economy and Competitiveness supported this research. We thank Fundación Ramón Areces for the institutional grant to the Centro de Biología Molecular Severo OchoaPeer Reviewe