A preliminary study on electrocatalytic reduction of CO2 using FAC-ReI(CO)3(4,4′-dimethyl-2,2′-bipyridyl)((E)-2-((3-amino-pyridin-4-ylimino)-methyl)-4,6-DI-tert-butylphenol))+ complex

Indexación: Scopus.Several research to explore the possible conversion of CO2 using rhenium(I) tricarbonyl complexes have been reported the last years. In the present work, we investigated a potential use of fac-Re(CO)3(4,4′-di-methyl-2,2′-bipyridyl)L+ complex (C2), where L is an electron-withdrawing ancillary ligands which present an intramolecular hydrogen bond (IHB), in a preliminary electrocatalytic reduction of CO2. The C2 complex was synthesized and characterized according to reported methods earlier. The cyclic voltammogram profle for the C2 complex were studied in dichloromethane under inert atmosphere, and it shows a typical behavior for an electrocatalytic process, the C2 complex illustrate the electrochemical reaction mechanism corresponds to an electrochemical-chemical-electrochemical pathway (ECE). Also, a Vitreous Carbon plate used as working electrode was employed and modifed by cycling the anodic region of C2 in CH2Cl2 which involve the oxidative redox response for the -NH2 and -OH groups. The voltammogram profle involve shows a polymeric deposit on the plate surface in a CO2 saturated solution (pH=7.0). A strong electrocatalytic discharge of current is obtained with a wave foot of -1.3 V showing that C2 have the potential to be used in electrocatalyst CO2 reduction. © 2017 Sociedad Chilena de Quimica. All Rights Reserved.https://scielo.conicyt.cl/pdf/jcchems/v62n4/0717-9324-jcchems-62-04-3765.pd

Libertad, destino y poder en “La hija del aire” de Calderón

“La hija del aire” de Calderón, cuya “Primera parte” se complementa con la “Segunda”, es una buena muestra de las nefastas consecuencias que acarrean la mala conducta de los gobernantes, sus intrigas y su afán de poder. El drama es un buen ejemplo de las crisis que provoca la presencia de una confusa e intrigante monarquía, que transciende más allá de las tablas. Se proyecta en el espacio político de los espectadores del siglo XVII. La figura central de la “Primera parte”, Semíramis, conduce su gobierno movida por la pasión de poder y por la tiranía. El modelo de gobierno que representa su hijo en la “Segunda parte”, el imprudente Ninías, es igualmente perjudicial para la nación. Su inexperiencia y desidia ante las obligaciones de su puesto, provocan la inestabilidad política y social. Ambos poderosos se muestran incapaces de controlar las pasiones que obnubilan la razón (los celos, la venganza, el rencor) y de seguir el camino medio de la virtud: la llamada vía mediocritas. Las dos partes del drama postulan, como gobierno a evitar, la necesidad del control de los instintos primarios de quien rige y de educar en el buen gobierno, dentro del concepto pedagógico del speculum principis, a los regidores de un país. El regente corrupto, rijoso, dominado por validos y por sus propios instintos de dominio provoca la inestabilidad y la degeneración. Arriesga con su conducta la supervivencia del estado que dirige. En este sentido, “La hija del aire” casa justamente, como representación poética y dramática, dentro de los dramas que muestran, en una segunda lectura, poderosas e intrigantes alegorías de las crisis del poder

Dipole-dipole interaction between a quantum dot and graphene nanodisk

We study theoretically the dipole-dipole interaction and energy transfer in a hybrid system consisting of a quantum dot and graphene nanodisk embedded in a nonlinear photonic crystal. In our model a probe laser field is applied to measure the energy transfer between the quantum dot and graphene nanodisk while a control field manipulates the energy transfer process. These fields create excitons in the quantum dot and surface plasmon polaritons in the graphene nanodisk which interact via the dipole-dipole interaction. Here the nonlinear photonic crystal acts as a tunable photonic reservoir for the quantum dot, and is used to control the energy transfer. We have found that the spectrum of power absorption in the quantum dot has two peaks due to the creation of two dressed excitons in the presence of the dipole-dipole interaction. The energy transfer rate spectrum of the graphene nanodisk also has two peaks due to the absorption of these two dressed excitons. Additionally, energy transfer between the quantum dot and the graphene nanodisk can be switched on and off by applying a pump laser to the photonic crystal or by adjusting the strength of the dipole-dipole interaction. We show that the intensity and frequencies of the peaks in the energy transfer rate spectra can be modified by changing the number of graphene monolayers in the nanodisk or the separation between the quantum dot and graphene. Our results agree with existing experiments on a qualitative basis. The principle of our system can be employed to fabricate nano-biosensors, optical nano-switches, and energy transfer devices

New properties of a bioinspired pyridine benzimidazole compound as a novel differential staining agent for endoplasmic reticulum and Golgi apparatus in fluorescence live cell imaging

Indexación: Scopus.In this study, we explored new properties of the bioinspired pyridine benzimidazole compound B2 (2,4-di-tert-butyl-6-(3H-imidazo[4,5-c]pyridine-2-yl)phenol) regarding its potential use as a differential biomarker. For that, we performed 1D 1HNMR (TOCSY), UV-Vis absorption spectra in different organic solvents, voltammetry profile (including a scan-rate study), and TD-DFT calculations that including NBO analyses, to provide valuable information about B2 structure and luminescence. In our study, we found that the B2 structure is highly stable, where the presence of an intramolecular hydrogen bond (IHB) seems to have a crucial role in the stability of luminescence, and its emission can be assigned as fluorescence. In fact, we found that the relatively large Stokes Shift observed for B2 (around 175 nm) may be attributed to the stability of the B2 geometry and the strength of its IHB. On the other hand, we determined that B2 is biocompatible by cytotoxicity experiments in HeLa cells, an epithelial cell line. Furthermore, in cellular assays we found that B2 could be internalized by passive diffusion in absence of artificial permeabilization at short incubation times (15 min to 30 min). Fluorescence microscopy studies confirmed that B2 accumulates in the endoplasmic reticulum (ER) and Golgi apparatus, two organelles involved in the secretory pathway. Finally, we determined that B2 exhibited no noticeable blinking or bleaching after 1 h of continuous exposure. Thus, B2 provides a biocompatible, rapid, simple, and efficient way to fluorescently label particular organelles, producing similar results to that obtained with other well-established but more complex methods. © 2018 Llancalahuen, Fuentes, Carreño, Zúñiga, Páez-Hernández, Gacitúa, Polanco, Preite, Arratia-Pérez and Otero.https://www.frontiersin.org/articles/10.3389/fchem.2018.00345/ful

Crime and Punishment in the UK: The Criminal Justice Act 2003 reduces deterrence within the UK criminal justice system

Deterrence under the Criminal Justice Act 2003: A critical appreciation of the effectiveness of its innovative criminal policy and the struggle between the outcome of a controversial political decision and the principle of proportionality

Seismic site classification from the horizontal-to-vertical response spectral ratios: use of the Spanish strong-motion database

Normally, the average of the horizontal-to-vertical (H/V) ratios of the 5% damped response spectra of ground motions is used to classify the site of strong-motion stations. In these cases, only the three-orthogonal as-recorded acceleration components are used in the analysis, and all the vector compositions that can generate a different response for each period oscillator are excluded. In this study, the Spanish strong-motion database was used to classify the sites of accelerometric stations based on the predominant periods through the average horizontal-to-vertical spectral ratios (HVSR) of recorded ground motions. Moreover, the directionality effects using the vector composition of the horizontal components of ground motions were also considered in the estimations of H/V ratios. This consideration is a relevant novelty compared to the traditional H/V ratios methods. Only earthquakes with magnitudes above 3.5 and hypocentral distances below 200 km were selected, which resulted in 692 ground-motion records, corresponding to 86 stations, from events in the period between 1993 and 2017. After the analysis, a predominant-period site classification was assigned to each station. On the whole, the obtained mean and standard deviation values of the spectral ratios are comparable to those shown by other researchers. Therefore, the advantages of the proposed procedure, which takes the directionality effects into account, can be summarized as follows: (a) The obtained information is richer and gives enables more sophisticated and realistic analyses on the basis of percentiles and (b) it is easier to detect anomalous stations, sites, and/or accelerograms. Moreover, the method eliminates the effect of directionality as a contributor to epistemic uncertainty.Peer ReviewedPostprint (published version

Analyzing rare event, anomaly, novelty and outlier detection terms under the supervised classification framework

In recent years, a variety of research areas have contributed to a set of related problems with rare event, anomaly, novelty and outlier detection terms as the main actors. These multiple research areas have created a mix-up between terminology and problems. In some research, similar problems have been named differently; while in some other works, the same term has been used to describe different problems. This confusion between terms and problems causes the repetition of research and hinders the advance of the field. Therefore, a standardization is imperative. The goal of this paper is to underline the differences between each term, and organize the area by looking at all these terms under the umbrella of supervised classification. Therefore, a one-to-one assignment of terms to learning scenarios is proposed. In fact, each learning scenario is associated with the term most frequently used in the literature. In order to validate this proposal, a set of experiments retrieving papers from Google Scholar, ACM Digital Library and IEEE Xplore has been carried out

Impacto Transmicable

The problem of mobility is one of the many issues that arise in cities. For this reason, territorial planning and how to get around is a fundamental pillar for the construction of society. In Bogotá (Colombia) the issue of mobility is very complex, especially in the most remote neighborhoods. The integrated Transmilenio system tries to control the problem, however, several factors such as population growth with an average of 1.87% per year reduce its capacity. This expansion significantly affects the environment, increases congestion, the accident rate, and creates an inability of movement and accessibility. The implementation of new transportation systems is a relevant factor for proper functioning. Projects such as the Transmicable not only provide a solution to the mobility issue but also have constructions with social benefits.El problema de la movilidad es uno de los tantos que se presentan en las ciudades. Por ello la planeación del territorio y el cómo transportarse es un pilar fundamental para la construcción de sociedad. En Bogotá (Colombia) el tema de la movilidad es muy complejo, sobre todo en los barrios más alejados. El sistema integrado de Transmilenio trata de controlar el problema, sin embargo varios factores como el crecimiento de la población con un promedio de 1.87% por año reducen su capacidad. Esta expansión afecta significativamente el medio ambiente, aumenta la congestión, la tasa de accidentes, y crea incapacidad de movimiento y accesibilidad. La implementación de nuevos sistemas de transporte es un factor relevante para el buen funcionamiento. Proyectos como el Transmicable no solo da solución al tema de movilidad sino que además cuenta con construcciones con beneficio social