Benthic macroinvertebrate communities in Salado and Loa Rivers, Antofagasta Region, Chile

The Loa River is the longest Chilean river with 440 km, located in the Atacama Desert. It has three tributaries’ rivers, and its fauna has been poorly studied, due to mainly access difficulties. The aim of the present study was the first characterization of benthic invertebrate community structure in a confluence of Loa and Salado rivers considering the derive invertebrates and benthic communities. The results revealed that species composition in benthic samples has no significant differences between Salado and Loa rivers before the confluence with Salado River, but both sites had significantly high species numbers in comparison to Loa River in Calama after Salado confluence whereas in derive species composition did not have species differences. Finally, the results of null models revealed that species number for three sites had no structured pattern for benthic and derive samples. Ecological and biogeographical topics were discussed here

TiO2/Au/TiO2 multilayer thin-film photoanodes synthesized by pulsed laser deposition for photoelectrochemical degradation of organic pollutants

Most commonly employed anodes for photoelectrochemical degradation of organic contaminants in water are too thick, resulting in a low degradation efficiency due to the excessive electron-hole recombination. Multilayer-type TiO 2 /Au/TiO 2 nanocomposites have been prepared as photoanode thin films by pulsed laser deposition (PLD). The films were composed of six TiO 2 and five Au alternate layers, with total thickness of about 212 nm, aimed to optimize the absorption of photons and minimize the recombination. The influence of gold on the optical, structural, and chemical properties of the semiconductor nanocomposites was investigated. The band gap determined from Tauc model was 3.22 eV, close to that obtained by spectroscopic ellipsometry and lower than that of the TiO 2 film, revealing an enhancement of visible light absorption. The catalytic performance of PLD films was evaluated by using them as anodes in electro-oxidation (EO) and photoanodes in photoelectrocatalysis (PEC) to degrade 39-157 mg L ⁻¹ paracetamol in sulfate medium. The drug removal was very slow in EO, due to the low ability to form [rad] OH on the anode surface, which was significantly enhanced upon UVA irradiation in PEC. The presence of Cl ⁻ allowed a faster degradation by produced active chlorine. Finally, a hybrid process involving PEC + photoelectro-Fenton (PEF) with an air-diffusion cathode yielded total paracetamol decay in 4-5 min at an anodic potential of +4.0 V because of the efficient [rad] OH generation from Fenton's and photo-Fenton reactions. Hydroquinone, p-benzoquinone and hydroxylated products were detected during EO and PEC. The generation of active chlorine was confirmed by identifying a chlorinated derivative, N-(4-chloro-2-hydroxyphenyl)acetamide, in PEC + PEF treatment

Synthesis of Spherical 4R Mechanism for Path Generation using Differential Evolution

The problem of path generation for the spherical 4R mechanism is solved using the Differential Evolution algorithm (DE). Formulas for the spherical geodesics are employed in order to obtain the parametric equation for the generated trajectory. Direct optimization of the objective function gives the solution to the path generation task without prescribed timing. Therefore, there is no need to separate this task into two stages to make the optimization. Moreover, the order defect problem can be solved without difficulty by means of manipulations of the individuals in the DE algorithm. Two examples of optimum synthesis showing the simplicity and effectiveness of this approach are included.Comment: Submitted to Mechanism and Machine Theor

Enantiopure 4‐oxazolin‐2‐ones and 4‐methylene‐2‐oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles

En este trabajo se describe la reactividad de las oxazolidin-2-onas en un ambiente quiral obteniéndose resultados novedosos, los cuales se describen extensamente.Enantiopure 3‐((R)‐ and 3‐((S)‐1‐phenylethyl)‐4‐oxazoline‐2‐ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N‐(R)‐ or N‐(S)‐1‐phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric induction of the 4‐ and 5‐positions of the 4‐oxazolin‐2‐one ring through thermal and MW‐promoted nucleophilic conjugated addition to Michael acceptors and alkyl halides. The resulting adducts were transformed via a cascade process into fused six‐membered carbo‐ and heterocycles. The structure of the reaction products depended on the electrophiles and reaction conditions used. Alternative isomeric 4‐methylene‐2‐oxazolidinones served as chiral precursors for a versatile and divergent approach to highly substituted cyclic carbamates. DFT quantum calculations showed that the formation of bicyclic pyranyl compounds was generated by a diastereoselective concerted hetero‐Diels‐Alder cycloaddition.Instituto Politécnico Nacional, Secretaria de Investigación y Estudios Avanzados de la Universidad Autónoma del Estado de México, Universidad de Guanajuato y CONACYT

Accesibilidad web en un sistema de administración académica desde dispositivos móviles

En la sociedad del conocimiento se intensifica la comunicación de información a través de entornos web y dispositivos móviles. La accesibilidad web como criterio de calidad en los sistemas informáticos y su interés a nivel internacional día a día cobra más relevancia. Se sintetizan los resultados obtenidos al revisar validadores automáticos un sistema de administración/gestión académica siguiendo las pautas WCAG 2.0 desde dispositivos móviles.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Accesibilidad web en un sistema de administración académica desde dispositivos móviles

En la sociedad del conocimiento se intensifica la comunicación de información a través de entornos web y dispositivos móviles. La accesibilidad web como criterio de calidad en los sistemas informáticos y su interés a nivel internacional día a día cobra más relevancia. Se sintetizan los resultados obtenidos al revisar validadores automáticos un sistema de administración/gestión académica siguiendo las pautas WCAG 2.0 desde dispositivos móviles.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Accesibilidad web en un sistema de administración académica desde dispositivos móviles

En la sociedad del conocimiento se intensifica la comunicación de información a través de entornos web y dispositivos móviles. La accesibilidad web como criterio de calidad en los sistemas informáticos y su interés a nivel internacional día a día cobra más relevancia. Se sintetizan los resultados obtenidos al revisar validadores automáticos un sistema de administración/gestión académica siguiendo las pautas WCAG 2.0 desde dispositivos móviles.Sociedad Argentina de Informática e Investigación Operativa (SADIO

Human Oncoprotein 5MP Suppresses General and Repeat-Associated Non-AUG Translation via eIF3 by a Common Mechanism

eIF5-mimic protein (5MP) is a translational regulatory protein that binds the small ribosomal subunit and modulates its activity. 5MP is proposed to reprogram non-AUG translation rates for oncogenes in cancer, but its role in controlling non-AUG initiated synthesis of deleterious repeat-peptide products, such as FMRpolyG observed in fragile-X-associated tremor ataxia syndrome (FXTAS), is unknown. Here, we show that 5MP can suppress both general and repeat-associated non-AUG (RAN) translation by a common mechanism in a manner dependent on its interaction with eIF3. Essentially, 5MP displaces eIF5 through the eIF3c subunit within the preinitiation complex (PIC), thereby increasing the accuracy of initiation. In Drosophila, 5MP/Kra represses neuronal toxicity and enhances the lifespan in an FXTAS disease model. These results implicate 5MP in protecting cells from unwanted byproducts of non-AUG translation in neurodegeneration

Pautas WCAG: métodos y herramientas en el análisis y desarrollo de sitios web

Se resume los logros en la aplicación de métodos y herramientas destinadas a medir las pautas de accesibilidad de los contenidos web (WCAG 1.0 y 2.0) de diversos sitios, enfatizando en aquellos pertenecientes a organizaciones del NE y orientados a diversos dominios del conocimiento. Se consolida la formación de recursos humanos en la temática, incorporando los estudios realizados en el desarrollo de becas otorgadas por la UNNE y tesinas de grado.Eje: Ingeniería de SoftwareRed de Universidades con Carreras en Informática (RedUNCI