Pigments and paints in Antofagasta de la sierra. compositional analysis of minerals and ceramic surfaces (province of Catamarca, Argentina)

Se presentan los resultados obtenidos sobre el estudio composicional de pinturas y engobes aplicados sobre cerámica arqueológica de distintos estilos recuperada en Punta de la Peña, Peñas Coloradas y Paicuqui, localidades arqueológicas de la microrregión de Antofagasta de la Sierra (Provincia de Catamarca, Argentina). Se evalúa la variabilidad de minerales empleados tanto en piezas de producción local como en recipientes de procedencia alóctona. Además, se detectó que en Paicuqui afloran depósitos de minerales colorantes de distintas tonalidades y se recuperaron también evidencias de procesamiento de pigmentos. A través de análisis por Difracción de Rayos X y Microespectroscopía Raman se caracteriza la composición de estas materias primas y se discute su posible uso en la cerámica estudiada. La información generada contribuye, por un lado, al conocimiento de las prácticas locales de producción, circulación y consumo de alfarería y de saberes para su elaboración que se desarrollaron en la región en el rango cronológico ca. 1000-1500 DC y, además, conforma el principio de una base de datos necesaria para la referencia de fuentes de pigmentos, escasamente registrados en el Noroeste Argentino.The results of compositional studies of paints and slips applied on archaeological ceramics of different styles recovered at Punta de la Peña, Peñas Coloradas and Paicuqui, archaeological sites of Antofagasta de la Sierra microrregion (Catamarca Province, Argentina), are presented and discussed. The variability of minerals used in local, as well as, in foreign pieces is evaluated. Furthermore, pigment deposits of diverse colors and also evidences of pigment processing were found. These materials were characterized by X-ray diffraction and Raman microspectroscopy and their possible appli cation in the fabrication of the studied ceramics is discussed. This information may contribute to the knowledge of the local pottery production, circulation ways and use, and of the elaboration techniques developed in this region during the chronological range ca. 1000-1500 AD. Also, may serve as the start of an empirical reference database of raw materials sources, which are scarcely registered in Argentine Northwest.Fil: Puente, Veronica. Universidad Nacional de Mar del Plata. Facultad de Humanidades. Departamento de Historia. Laboratorio de Arqueología Regional Bonaerense; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; ArgentinaFil: Desimone, Paula Mariela. 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: Porto Lopez, Jose Manuel. Universidad Nacional de Mar del Plata. Facultad de Humanidades. Departamento de Historia. Laboratorio de Arqueología Regional Bonaerense; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentin

Microstructure and properties of Fe3O4/BaTiO3/epoxy composites

Con el objetivo de estudiar nuevos materiales multipropósito, en este trabajo se analizó la influencia de las partículas de Fe3O4 y BaTiO3 sobre las propiedades magnéticas y dieléctricas de los sistemas Fe3O4/BaTiO3/epoxi. A tal efecto se analizaron los sistemas bifásicos Fe3O4/epoxi y BaTiO3/epoxi y a partir del análisis de los resultados se conformaron los compuestos Fe3O4/BaTiO3/epoxi. En todos los casos los valores de permitividad y pérdidas dieléctricas fueron altamente influenciados por el contenido de carga. En este sentido, los materiales procesados con Fe3O4 presentaron muy elevadas pérdidas dieléctricas para altas concentraciones de carga debido a efectos de percolación y a las propiedades semiconductoras del Fe3O4.The influence of Fe3O4 and BaTiO3 on dielectric and magnetic properties of Fe3O4/BaTiO3/epoxy composites was studied. Initially, biphasic Fe3O4/epoxy and BaTiO3/epoxy composites were analyzed, and based on these results Fe3O4/BaTiO3/epoxy composite were conformed. In all the cases, dielectric properties were influenced by the frequency and filler concentration. In this way, Fe3O4/epoxy composites with high filler concentration showed high dielectric loss due to percolation effects and semiconducting properties of Fe3O4.Fil: Ramajo, Leandro Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Cristobal, Adrian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Porto Lopez, Jose Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Botta, Pablo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Reboredo, Maria Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; ArgentinaFil: Castro, Miriam Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentin

Production and Characterization of MnZn Ferrites from ZnFe2O4-MnFe2O4 Mixtures

Se estudió la síntesis de ferritas de MnZn en tres composiciones diferentes en el sistema MnxZn1-xFe2O4, con x=0,50; 0,65 y 0,85, a partir de las ferritas MnFe2O4 y ZnFe2O4. Con estas espinelas, sintetizadas previamente, se prepararon mezclas íntimas que fueron compactadas en forma de pastillas y sometidas a tratamiento térmico a 1100ºC en atmósfera de N2, durante distintos tiempos. Los materiales así obtenidos fueron caracterizados por difracción de rayos x (DRX), análisis térmico diferencial y gravimétrico (ATD/TG), magnetometría de muestra vibrante (VSM) y microscopía electrónica de barrido (SEM). Además se midieron las densidades de las pastillas sinterizadas, para las tres composiciones estudiadas. Se observó la formación de las fases deseadas para cada caso, con densidades entre un 80 y 85% del valor teórico y propiedades magnéticas que superan el 90% de los valores reportados en literatura. Se comparan estos valores con los correspondientes a estas ferritas preparadas por otros métodos. Se discute el efecto de las variables de procesamiento sobre la morfología y propiedades de los materiales sintetizados.The synthesis of MnxZn1-xFe2O4 (x = 0.5, 0.65 and 0.85) starting from single ferrites ZnFe2O4 and MnFe2O4 is studied. Powder mixtures of these spinels were prepared and subsequently, they were compacted and submitted to thermal treatment at 1100ºC under N2 atmosphere during several holding times. The obtained materials were characterized by X-ray diffraction (XRD), differential and gravimetric thermal analysis (DTA/TG), vibrating sample magnetometry (VSM) and scanning electron microscopy (SEM). Also the density of the sintered ferrites was determined. For the three studied compositions, the formation of expected mixed ferrites was observed, reaching densities of 80-85% of the theoretical values and magnetic properties that exceeded 90% of the reported data. These values are compared with those corresponding to ferrites synthesized by conventional methods. The effect of processing parameters on the morphology and properties of the obtained materials is discussed.Fil: Botta, Pablo Martín. 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: Bercoff, Paula Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; Argentina. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Aglietti, Esteban Fausto. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Tecnología de Recursos Minerales y Cerámica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Tecnología de Recursos Minerales y Cerámica; ArgentinaFil: Bertorello, Hector Raul. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Física Enrique Gaviola. Universidad Nacional de Córdoba. Instituto de Física Enrique Gaviola; ArgentinaFil: Porto Lopez, Jose Manuel. 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; Argentin

Identification of regulatory variants associated with genetic susceptibility to meningococcal disease.

Non-coding genetic variants play an important role in driving susceptibility to complex diseases but their characterization remains challenging. Here, we employed a novel approach to interrogate the genetic risk of such polymorphisms in a more systematic way by targeting specific regulatory regions relevant for the phenotype studied. We applied this method to meningococcal disease susceptibility, using the DNA binding pattern of RELA - a NF-kB subunit, master regulator of the response to infection - under bacterial stimuli in nasopharyngeal epithelial cells. We designed a custom panel to cover these RELA binding sites and used it for targeted sequencing in cases and controls. Variant calling and association analysis were performed followed by validation of candidate polymorphisms by genotyping in three independent cohorts. We identified two new polymorphisms, rs4823231 and rs11913168, showing signs of association with meningococcal disease susceptibility. In addition, using our genomic data as well as publicly available resources, we found evidences for these SNPs to have potential regulatory effects on ATXN10 and LIF genes respectively. The variants and related candidate genes are relevant for infectious diseases and may have important contribution for meningococcal disease pathology. Finally, we described a novel genetic association approach that could be applied to other phenotypes

Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Dementia in Latin America : paving the way towards a regional action plan

Regional challenges faced by Latin American and Caribbean countries (LACs) to fight dementia, such as heterogeneity, diversity, political instabilities, and socioeconomic disparities, can be addressed more effectively grounded in a collaborative setting based on the open exchange of knowledge. In this work, the Latin American and Caribbean Consortium on Dementia (LAC-CD) proposes an agenda for integration to deliver a Knowledge to Action Framework (KtAF). First, we summarize evidence-based strategies (epidemiology, genetics, biomarkers, clinical trials, nonpharmacological interventions, networking and translational research) and align them to current global strategies to translate regional knowledge into actions with transformative power. Then, by characterizing genetic isolates, admixture in populations, environmental factors, and barriers to effective interventions and mapping these to the above challenges, we provide the basic mosaics of knowledge that will pave the way towards a KtAF. We describe strategies supporting the knowledge creation stage that underpins the translational impact of KtAF

Plasma lipid profiles discriminate bacterial from viral infection in febrile children

Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection are often non-specific, and there is no definitive test for the accurate diagnosis of infection. The 'omics' approaches to identifying biomarkers from the host-response to bacterial infection are promising. In this study, lipidomic analysis was carried out with plasma samples obtained from febrile children with confirmed bacterial infection (n = 20) and confirmed viral infection (n = 20). We show for the first time that bacterial and viral infection produces distinct profile in the host lipidome. Some species of glycerophosphoinositol, sphingomyelin, lysophosphatidylcholine and cholesterol sulfate were higher in the confirmed virus infected group, while some species of fatty acids, glycerophosphocholine, glycerophosphoserine, lactosylceramide and bilirubin were lower in the confirmed virus infected group when compared with confirmed bacterial infected group. A combination of three lipids achieved an area under the receiver operating characteristic (ROC) curve of 0.911 (95% CI 0.81 to 0.98). This pilot study demonstrates the potential of metabolic biomarkers to assist clinicians in distinguishing bacterial from viral infection in febrile children, to facilitate effective clinical management and to the limit inappropriate use of antibiotics

Structural analysis of modified hydroxyapatite powders

In this work, the presence of structural defects in modified hydroxyapatite (HA) samples were studied. The behavior of HA samples with different chemical compositions was compared. Structural alterations were produced by thermal treatments and high-energy milling. Electron paramagnetic resonance spectroscopy (EPR) was used in order to identify the presence of structural defects. Samples were analyzed at room temperature and the signals observed by electron paramagnetic resonance at g = 1.999 were assigned to oxygen vacancies in the apatitic structure. The determination of vacancy concentration (Vo·) in each sample was related with the characteristic parameters of the signal and the experimental conditions. XRD and SEM were used as additional characterization techniques. The production and concentration of these vacancies was correlated to the modifications introduced during the processing of the materials. The results were also related with the chemical composition, particle size and crystallinity of the samples.Fil: Fanovich, Maria Alejandra. 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: Castro, Miriam Susana. 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: Porto Lopez, Jose Manuel. 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; Argentin

Kinetic study of ZnFe2O4 formation from mechanochemically activated Zn-Fe2O3 mixtures

The kinetics of ZnFe2O4 formation starting from mechanochemically activated Zn-Fe2O3 powders are studied. Mixtures of metallic Zn and hematite were activated under air atmosphere in a high energy mill and thermally treated at temperatures between 500 and 650 °C during several holding times. During the activation, morphological and compositional changes were observed, but ZnFe2O4 formation was not detected. The ZnFe2O4 content in heated samples was determined using quantitative X-ray diffraction analysis. The resulting conversion-time curves were fitted using different kinetic models of solid-state reaction, calculating the kinetic parameters of the studied reaction. The comparison with the conventional synthesis method revealed that the mechanochemical treatment provoked a change of the rate-controlling step and a significant decrease of the activation energy, which was more evident for the more activated mixtures.Fil: Botta, Pablo Martín. 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: Aglietti, Esteban Fausto. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Tecnología de Recursos Minerales y Cerámica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Tecnología de Recursos Minerales y Cerámica; ArgentinaFil: Porto Lopez, Jose Manuel. 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; Argentin