A Structural Comparison of Ordered and Non-Ordered Ion Doped Silicate Bioactive Glasses

One of the key benefits of sol-gel-derived glasses is the presence of a mesoporous structure and the resulting increase in surface area. This enhancement in textural properties has a significant e ect on the physicochemical properties of the materials. In this context the aim of this study was to investigate how sol-gel synthesis parameters can influence the textural and structural properties of mesoporous silicate glasses. We report the synthesis and characterization of metal ion doped sol-gel derived glasses with di erent dopants in the presence or absence of a surfactant (Pluronic P123) used as structure-directing templating agent. Characterization was done by several methods. Using a structure directing agent led to larger surface areas and highly ordered mesoporous structures. The chemical structure of the non-ordered glasses was modified to a larger extent than the one of the ordered glasses due to increased incorporation of dopant ions into the glass network. The results will help to further understand how the properties of sol-gel glasses can be controlled by incorporation of metal dopants, in conjunction with control over the textural properties, and will be important to optimize the properties of sol-gel glasses for specific applications, e.g., drug delivery, bone regeneration, wound healing, and antibacterial materials.European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 643050, project “HyMedPoly

Incorporation of Calcium Containing Mesoporous (MCM-41-Type) Particles in Electrospun PCL Fibers by Using Benign Solvents

The electrospinning technique is a versatile method for the production of fibrous scaffolds able to resemble the morphology of the native extra cellular matrix. In the present paper, electrospinning is used to fabricate novel SiO2 particles (type MCM-41) containing poly(epsilon-caprolactone) (PCL) fibers. The main aims of the present work are both the optimization of the particle synthesis and the fabrication of composite fibers, obtained using benign solvents, suitable as drug delivery systems and scaffolds for soft tissue engineering applications. The optimized synthesis and characterization of calcium-containing MCM-41 particles are reported. Homogeneous bead-free composite electrospun mats were obtained by using acetic acid and formic acid as solvents; neat PCL electrospun mats were used as control. Initially, an optimization of the electrospinning environmental parameters, like relative humidity, was performed. The obtained composite nanofibers were characterized from the morphological, chemical and mechanical points of view, the acellular bioactivity of the composite nanofibers was also investigated. Positive results were obtained in terms of mesoporous particle incorporation in the fibers and no significant differences in terms of average fiber diameter were detected between the neat and composite electrospun fibers. Even if the Ca-containing MCM-41 particles are bioactive, this property is not preserved in the composite fibers. In fact, during the bioactivity assessment, the particles were released confirming the potential application of the composite fibers as a drug delivery system. Preliminary in vitro tests with bone marrow stromal cells were performed to investigate cell adhesion on the fabricated composite mats, the positive obtained results confirmed the suitability of the composite fibers as scaffolds for soft tissue engineerin

Weight bias internalization among adolescents in Spain: psychological correlates across gender diversity and weight status

Weight bias internalization refers to the negative weight-related attributions applied to oneself, but it does not just occur in the highest weight statuses, but rather exists across the entire weight spectrum. There is a negative impact associated to increase psychological problems in adults, however, it has been less studied among the adolescent Spanish population. In this study, we assess the relationship between the internalization of weight bias, social attitudes towards appearance, body appreciation and self-esteem, and potential differences regarding gender and weight status. A community sample of 1258 Spanish adolescents between 12 and 18 years old (46.3% male gender; Mage = 15.58; SD = 1.59; 49.5% female gender; Mage = 15.59; SD = 1.67; and 4.1% non-binary gender; Mage = 14.86; SD = 2.86) participated in the study. The Modified Weight Bias Internalization Scale (WBIS-M), the Rosenberg Self-Esteem Scale (RSES), and the Sociocultural Attitudes Towards Appearance Questionnaire (SATAQ-4) were used. ANOVA’s test and bivariate correlations were performed. The results suggest that females (t = -.55; p ≤ .001) and non-binary adolescents (t = .64; p ≤ .01) have higher levels of WBI-M compared to males. Regarding weight status, the group with obesity (t = 1.39; p ≤ .001) and the group with overweight (t = -.81; p ≤ .001) have higher levels of WBI-M compared to the normal weight group. Significant correlations between WBI-M and the assessed psychological variables were found in the total sample, and across all-gender and weight categories, except for the underweight group. These results are a first approximation to the internalization of weight bias in a Spanish adolescent sample and highlight the need to introduce this concept in prevention and psychological interventions in school context.La internalización de los prejuicios de peso entre los y las adolescentes en España: correlatos psicológicos en función del género y el estatus de peso. La internalización de los prejuicios de peso hace referencia a las atribuciones negativas relacionadas con el peso aplicadas a uno mismo/a, lo cual no ocurre únicamente en las personas con un estatus de peso elevado, sino en todo el rango de pesos. En adultos, existe evidencia de su impacto negativo asociados a incrementar problemas psicológicos; aunque se ha estudiado en menor medida en la población adolescente. El objetivo de este estudio fue examinar la relación entre la internalización de prejuicios de peso, las actitudes socioculturales hacia la apariencia, la apreciación corporal y el nivel de autoestima, y analizar las posibles diferencias en función del género y del estatus de peso. Participaron 1.258 adolescentes españoles de una muestra comunitaria entre 12 y 18 años (46.3% género masculino; Medad = 15.58; DT = 1.59; 49,5% género femenino; Medad = 15.59; DT = 1.67; y 4.1% género no binario; Medad = 14.86; DT = 2.86). Se utilizaron la escala de internalización de prejuicios de peso modificado (WBIS-M), la escala de autoestima de Rosenberg (RSES) y el cuestionario de actitudes socioculturales hacia la apariencia (SATAQ-4). Se realizó la prueba ANOVA y correlaciones bivariadas. Los resultados sugieren que el grupo identificado con el género femenino (t = -.55; p ≤ .001) y con el no binario (t = .64; p ≤ .01) muestran niveles más altos de internalización del sesgo de peso en comparación con el género masculino. En cuanto al estado ponderal, el grupo con obesidad (t = 1.39; p ≤ .001) y el grupo con sobrepeso (t = -.81; p ≤ .001) presentan niveles más altos de internalización de prejuicios de peso en comparación con el grupo con normopeso. Se encontraron correlaciones significativas entre las puntuaciones del WBIS-M y las variables psicológicas evaluadas en la muestra total y en todas las categorías de género y peso, con la excepción del grupo de bajo peso. Estos resultados son una primera aproximación a la interiorización del estigma del peso en una muestra adolescente española y resalta la necesidad de incluir esta dimensión en la prevención de las alteraciones de la imagen corporal y los problemas psicológicos relacionados con la autoestima entre adolescentes en el contexto escolar

High performance novel gadolinium doped ceria/yttria stabilized zirconia/nickel layered and hybrid thin film anodes for application in solid oxide fuel cells

Magnetron sputtering under oblique angle deposition was used to produce Ni-containing ultra thin film anodes comprising alternating layers of gadolinium doped ceria (GDC) and yttria stabilized zirconia (YSZ) of either 200 nm or 1000 nm thickness. The evolution of film structure from initial deposition, through calcination and final reduction was examined by XRD, SEM, TEM and TOF-SIMS. After subsequent fuel cell usage, the porous columnar architecture of the two-component layered thin film anodes was maintained and their resistance to delamination from the underlying YSZ electrolyte was superior to that of corresponding single component Ni-YSZ and Ni-GDC thin films. Moreover, the fuel cell performance of the 200 nm layered an- odes compared favorably with conventional commercially available thick anodes. The observed dependence of fuel cell performance on individual layer thicknesses prompted study of equivalent but more easily fabricated hybrid anodes consisting of simultaneously deposited Ni-GDC and Ni-YSZ, which procedure resulted in exceptionally intimate mixing and interaction of the components. The hybrids exhibited very unusual and favorable I---V characteristics, along with exceptionally high power densities at high currents. Their discovery is the principal contribution of the present work.European Union's Seventh Framework Programme FP7/2007–2013Fuel Cells and Hydrogen Joint Technology Initiative under the T-CELL project, grant 298300MINECO (Spain), grants nº MAT2013-40852RJuan de la Cierva Programme FPDI-2013-1862

Combination of Selective Etching and Impregnation toward Hollow Mesoporous Bioactive Glass Nanoparticles

In this study, binary SiO2-CaO hollow mesoporous bioactive glass nanoparticles (HMBGNs) are prepared by combing selective etching and impregnation strategies. Spherical silica particles (SiO2 NPs) are used as hard cores to assemble cetyltrimethylammonium bromide (CTAB)/silica shells, which are later removed by selective etching to generate a hollow structure. After the removal of CTAB by calcination, the mesoporous shell of particles is formed. Calcium (Ca) is incorporated into the particles using impregnation by soaking the etched SiO2 NPs in calcium nitrate aqueous solution. The amount of incorporated Ca is tailorable by controlling the ratio of SiO2 NPs:calcium nitrate in the soaking solution. The produced HMBGNs are bioactive, as indicated by the rapid formation of hydroxyapatite on their surfaces after immersion in simulated body fluid. In a direct culture with MC3T3-E1 cells, HMBGNs were shown to exhibit concentration-dependent cytotoxicity and can stimulate osteogenic differentiation of MC3T3-E1 cells at concentrations of 1, 0.5, and 0.25 mg/mL. Our results indicate that the combination of selective etching and impregnation is a feasible approach to produce hierarchical HMBGNs. The produced hollow particles have potential in drug delivery and bone tissue regeneration applications, and should be further investigated in detailed in vitro and in vivo studies.European Union’s Horizon 2020 research and innovation program 685872-MOZAR

Surface functionalisation of sol-gel-based bioactive glass scaffolds for drug delivery

ITN FP-7 project “GlaCERCo

Acidithiobacillus ferrianus sp. nov.:an ancestral extremely acidophilic and facultatively anaerobic chemolithoautotroph

Strain MG, isolated from an acidic pond sediment on the island of Milos (Greece), is proposed as a novel species of ferrous iron- and sulfur-oxidizing Acidithiobacillus. Currently, four of the eight validated species of this genus oxidize ferrous iron, and strain MG shares many key characteristics with these four, including the capacities for catalyzing the oxidative dissolution of pyrite and for anaerobic growth via ferric iron respiration. Strain MG also grows aerobically on hydrogen and anaerobically on hydrogen coupled to ferric iron reduction. While the 16S rRNA genes of the iron-oxidizing Acidithiobacillus species (and strain MG) are located in a distinct phylogenetic clade and are closely related (98–99% 16S rRNA gene identity), genomic relatedness indexes (ANI/dDDH) revealed strong genomic divergence between strain MG and all sequenced type strains of the taxon, and placed MG as the first cultured representative of an ancestral phylotype of iron oxidizing acidithiobacilli. Strain MG is proposed as a novel species, Acidithiobacillus ferrianus sp. nov. The type strain is MGT(= DSM 107098T= JCM 33084T).Similar strains have been found as isolates or indicated by cloned 16S rRNA genes from several mineral sulfide mine sites.Indexación: Scopu

Trispyrazolylborate Ligands Supported on Vinyl Addition Polynorbornenes and Their Copper Derivatives as Recyclable Catalysts

Polynorbornenes prepared by vinyl addition poly- merization and bearing pendant alkenyl groups serve as skeletons to support trispyrazolylborate ligands (Tpx) built at those alkenyl sites. Reaction with CuI in acetonitrile led to VA-PNB–TpxCu(NCMe) (VA-PBN = vinyl addition polynorbor- nene) with a 0.8–1.4 mmol incorporation of Cu per gram of polymer. The presence of tetracoordinated copper(I) ions was been assessed by FTIR studies on the corresponding VA-PNB-TpxCu(CO) adducts, in agreement with those on discrete TpxCu(CO). The new materials were employed as heteroge- neous catalysts in several carbene- and nitrene-transfer reac- tions, showing a behavior similar to that of the homogene- ous counterparts but also being recycled several times main- taining a high degree of activity and selectivity. This is the first example of supported Tpx ligands onto polymeric sup- ports with catalytic applications.MINECO (CTQ2017-82893-C2-1-R, CTQ2016-80913-P and Red Intecat CTQ2016-81923-REDC)Junta de Castilla y León (VA051P17, VA062G18)European Union (CHAOS COST ACTION CA-15106)

Laboratory and industrial testing of silica bricks for coke ovens

In order to rationalize the reconstruction of coke ovens' walls in a local steelmaking, a set of laboratory and industrial tests was carried out on silica KN bricks. Two types of bricks that are currently used in oven construction were analyzed, one being less expensive than the other. On the other hand, 25 year-old original bricks were also studied. The results of laboratory tests were analyzed taking into account the requirements of DIN 1089 standard. Additionally, an evaluation of costs was carried out.Fil: Camerucci, Maria Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Tomba Martinez, Analia Gladys. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: Cavalieri, Ana Lia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; ArgentinaFil: de Córdova, M.. SIDERAR; ArgentinaFil: Beltrán, D.. SIDERAR; ArgentinaFil: Topolevsky, R.. SIDERAR; Argentin

Influence of Copper-Strontium Co-Doping on Bioactivity, Cytotoxicity and Antibacterial Activity of Mesoporous Bioactive Glass

Mesoporous bioactive glass (MBG) is an extensively studied biomaterial used for the healing of bone defects. Its biological applications can be tailored by introducing metallic ions, such as strontium (Sr) and copper (Cu), which can enhance its functionalities, including osteogenetic, angiogenetic and antibacterial functionalities. In this study, Cu and Sr ions were co-doped (ratio 1:1) with x = 0.5, 1 and 2 mol% each in glass with an intended nominal composition of 80SiO2-(15-2x)CaO-5P2O5-xCuO-xSrO and synthesized with an evaporation-induced self-assembly (EISA)-based sol-gel technique. XRD confirmed the amorphous nature of the glass, while compositional analysis using ICP-OES confirmed the presence of dopant ions with the required amounts. A TEM study of the MBG powders showed fringes that corresponded to the formation of a highly ordered mesoporous structure. The Cu-Sr-doped MBG showed a positive effect on apatite formation when immersed in SBF, although the release of Cu and Sr ions was relatively slow for 1 mol% of each co-dopant, which signified a stable network structure in the glass. The impact of the Cu and Sr ions on the osteoblast-like cell line MG-63 was assessed. At the particle concentrations of 1 wt./vol.% or lower, the cell viability was above 50%. An antibacterial test was conducted against Gram-negative E. coli and Gram-positive S. aureus bacteria. With a sequential increase in the co-doped ion content in the glass, the zone of inhibition for bacteria increased. The results suggest that the doping of MBG with Cu and Sr ions at up to 2 mol% can result in tailored sustained release of ions to enhance the applicability of the studied glass as a functional biomaterial for bone regeneration applications.European Union’s Horizon 2020 research and innovation program under grant number 739566VEGA 1/0191/2