22 research outputs found
Arabica‑cofee and teobroma‑cocoa agro‑industrial waste biosorbents, for Pb(II) removal in aqueous solutions
Agro-industrial waste biosorbents of arabica–cofee (WCA) and theobroma–cocoa (WCT) have been characterized and tested to remove Pb(II) from aqueous media. The maximum adsorption capacity of WCA and WCT (qmax = 158.7 and 123.5 mg·g−1, respectively) is comparable or even higher than for several other similar agro-industrial waste biosorbents reported in the literature. Structural and morphological characterization were performed by infrared spectrometry with Fourier transform (FT-IR), scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), and charge measurements at the zero point charge (pHPZC). Both biosorbents, WCA and WCT, show cracked surfaces with heterogeneous plates which ones include functional adsorption groups such as OH, C = O and C-O-C. Optimal Pb(II) adsorption occurs for a pH between 4 and 5 at [WCA] and [WCT] dose concentrations of 2 g·L−1. We found that the adsorption process follows pseudo-second order kinetics with a rapid growth rate (almost six times larger for WCA than for WCT), basically controlled by the chemisorption process. The regeneration of both biosorbents was carried out in an eluent of 0.1M HNO3 and they can be eficiently reused up to 5 times.Campus Lima Centr
The contribution of meteorological parameters and the COVID-19 partial lockdown on air quality in Rio de Janeiro, Brazil
This study evaluated the pollutant levels (NO2, SO2, CO, and O3), air quality index (AQI) and
the influence of meteorological variables and coronavirus disease (COVID-19) pandemic on the
air quality in Rio de Janeiro. The data set used comprises periods before (March-April, 2019) and
during pandemic (March-April, 2020). According to the AQI results, on most days, the air quality
was ranked as “good”. Brazilian air quality standards for SO2, O3, and NO2 were not exceeded in
any of the monitoring stations during partial lockdown, while CO exceeded in all periods in one
site due to industrial emission. Comparing both periods, descriptive statistics for the meteorological
parameters presented no differences, which suggests similar conditions. However, when evaluated
week by week in 2020, weather conditions presented some differences that probably affected
pollutant concentrations. The correlations between O3 and NO2 and some meteorological parameters
indicate that variations in both favored ozone formation, since it is a photochemical process favored
by temperature and solar radiation and that, in Rio de Janeiro, low NO2 concentrations lead to
increased O3. The improvements on air quality during the partial lockdown may be attributed
mainly to a reduction on emission sources rather than weather conditions.Campus Lima Centr
VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory
VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l.
in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design,
construction techniques and data acquisition system of the HAWC observatory.
HAWC is an air-shower array currently under construction at the same site of
VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water
Cherenkov detectors and two different data acquisition systems. It was in
operation between October 2011 and May 2012 with an average live time of 30%.
Besides the scientific verification purposes, the eight months of data were
used to obtain the results presented in this paper: the detector response to
the Forbush decrease of March 2012, and the analysis of possible emission, at
energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages,
10 figures). Corresponding authors: A.Marinelli and D.Zaboro
Nodavirus colonizes and replicates in the testis of gilthead seabream and European sea bass modulating its immune and reproductive functions
Viruses are threatening pathogens for fish aquaculture. Some of them are transmitted
through gonad fluids or gametes as occurs with nervous necrosis virus (NNV). In order to
be transmitted through the gonad, the virus should colonize and replicate inside some cell
types of this tissue and avoid the subsequent immune response locally. However, whether
NNV colonizes the gonad, the cell types that are infected, and how the immune response in
the gonad is regulated has never been studied. We have demonstrated for the first time the
presence and localization of NNV into the testis after an experimental infection in the European
sea bass (Dicentrarchus labrax), and in the gilthead seabream (Sparus aurata), a very
susceptible and an asymptomatic host fish species, respectively. Thus, we localized in the
testis viral RNA in both species using in situ PCR and viral proteins in gilthead seabream by
immunohistochemistry, suggesting that males might also transmit the virus. In addition, we
were able to isolate infective particles from the testis of both species demonstrating that
NNV colonizes and replicates into the testis of both species. Blood contamination of the tissues
sampled was discarded by completely fish bleeding, furthermore the in situ PCR and
immunocytochemistry techniques never showed staining in blood vessels or cells. Moreover,
we also determined how the immune and reproductive functions are affected comparing
the effects in the testis with those found in the brain, the main target tissue of the virus.
Interestingly, NNV triggered the immune response in the European sea bass but not in the
gilthead seabream testis. Regarding reproductive functions, NNV infection alters 17β-estradiol
and 11-ketotestosterone production and the potential sensitivity of brain and testis to
these hormones, whereas there is no disruption of testicular functions according to several
reproductive parameters. Moreover, we have also studied the NNV infection of the testis in
vitro to assess local responses. Our in vitro results show that the changes observed on the expression of immune and reproductive genes in the testis of both species are different to
those observed upon in vivo infections in most of the casesMINECO and FEDER (AGL2010-20801-C02-01; AGL2010-20801-C02-02; AGL2013-43588-P); Fundación Séneca (04538/GERM/06)Versión del editor4,411
Species composition and seasonal abundance of sandflies (Diptera: Psychodidae: Phlebotominae) in coffee agroecosystems
VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad
Acta de congresoLa conmemoración de los cien años de la Reforma Universitaria de 1918 se presentó como una ocasión propicia para debatir el rol de la historia, la teoría y la crítica en la formación y en la práctica profesional de diseñadores, arquitectos y urbanistas.
En ese marco el VIII Encuentro de Docentes e Investigadores en Historia del Diseño, la Arquitectura y la Ciudad constituyó un espacio de intercambio y reflexión cuya realización ha sido posible gracias a la colaboración entre Facultades de Arquitectura, Urbanismo y Diseño de la Universidad Nacional y la Facultad de Arquitectura de la Universidad Católica de Córdoba, contando además con la activa participación de mayoría de las Facultades, Centros e Institutos de Historia de la Arquitectura del país y la región.
Orientado en su convocatoria tanto a docentes como a estudiantes de Arquitectura y Diseño Industrial de todos los niveles de la FAUD-UNC promovió el debate de ideas a partir de experiencias concretas en instancias tales como mesas temáticas de carácter interdisciplinario, que adoptaron la modalidad de presentación de ponencias, entre otras actividades.
En el ámbito de VIII Encuentro, desarrollado en la sede Ciudad Universitaria de Córdoba, se desplegaron numerosas posiciones sobre la enseñanza, la investigación y la formación en historia, teoría y crítica del diseño, la arquitectura y la ciudad; sumándose el aporte realizado a través de sus respectivas conferencias de Ana Clarisa Agüero, Bibiana Cicutti, Fernando Aliata y Alberto Petrina. El conjunto de ponencias que se publican en este Repositorio de la UNC son el resultado de dos intensas jornadas de exposiciones, cuyos contenidos han posibilitado actualizar viejos dilemas y promover nuevos debates.
El evento recibió el apoyo de las autoridades de la FAUD-UNC, en especial de la Secretaría de Investigación y de la Biblioteca de nuestra casa, como así también de la Facultad de Arquitectura de la UCC; va para todos ellos un especial agradecimiento
Influence of Polysaccharides’ Molecular Structure on the Antibacterial Activity and Cytotoxicity of Green Synthesized Composites Based on Silver Nanoparticles and Carboxymethyl-Cellulose
In this paper we report on the influence of polysaccharides’ molecular structure on the antibacterial activity and cytotoxicity of composites based on silver nanoparticles (AgNPs) immobilized into carboxymethyl-cellulose (CMC). These composites were green synthesized from the reduction of silver ions into aqueous solutions of the polysaccharide, using CMC with different degree of substitution (DS) and molecular weight (Mw). The composites were characterized by transmission electron microscopy (TEM), as well as infrared (ATR-FTIR), ultraviolet (UV-Vis), Raman, and X-ray photo-electron (XPS) spectroscopic techniques. The antibacterial activity was evaluated with minimum inhibitory concentration against Enterococcus faecalis. The cytotoxicity of composites was assessed against human gingival fibroblast. Experimental evidence suggests that particle size distribution and morphology of AgNPs change according to the quantity of silver precursor added to the reaction, as well as the DS and Mw of CMC used for composites preparation. This is related to the dispersion of silver precursor into aqueous solutions of the polysaccharide and the formation of Ag-O coordination bonds among AgNPs and COO− moieties of CMC. Moreover, these coordination bonds modify the ability of nanoparticles to produce and release Ag+ into aqueous dispersion, adjusting their antibacterial activity and the induction of cytotoxicity into the tested biological environments
Assessment of amination reactions via nucleophilic aromatic substitution using conventional and eco-friendly energies
Resúmenes proyectos de investigación en Psicología con financiamiento del fondo nacional de desarrollo científico y tecnológico - FONDECYT, aprobados año 2011
During 2011 the Grants from FONDECYT for Regular Competitions 2012 and for Introduction to Research 2011 were
resolved. For Introduction to Research, 525 projects was submitted and 262 projects were approved. Of these, 7
corresponded to Psychology (from a total
of 12 projects nominated), with an amount of 322.630 million pesos, representing 2,3% of total awarded funding in this
category. In Regular Competition, from 1164 projects submitted for funding and 605 were approved. Of these, 11 projects
are from Psychology (out of 23 submitted), valued at 620.406 million, equivalent to 1.0% of the total amount allocated for
this competition. In this special report, all summaries from projects approved in the area are presented. They began to run
in November 2011 (Introduction) and will run until the period 2013-2014.Durante el año 2011 se resolvieron los concursos FONDECYT regular 2012 y de Iniciación a la investigación 2011. En el
concurso de Iniciación a la Investigación, se presentaron 525 proyectos, de los cuales fueron aprobaron 262. De estos, 7
corresponden a Psicología (de un total de 12 proyectos postulados), por un valor de 322.630 millones de pesos, lo que
constituye el 2,3% del total del financiamiento otorgado en esta categoría. En el concurso regular, de 1164 proyectos
postulados, se aprobaron para financiamiento 605. De estos, 11 proyectos corresponden a Psicología (de un total de 23
presentados), por un valor de 620.406 millones, lo que equivale al 1,0% del monto total asignado a este concurso. Se
presentan en este artículo especial, los resúmenes de la totalidad de proyectos aprobados para el área, los cuales
comenzaron a ejecutarse en noviembre del 2011 (iniciación) y que estarán ejecutándose hasta el periodo 2013-2014