Clodomiro Picado y sus años de formación científica

Se analizan una serie de factores socioeconómicos, políticas y culturales que jugaron un papel importante en los años de formación del científica costarricense Clodomiro Picado Twight. E! desarrollo político y cultural de Costa Rica durante la parte final del siglo XIX, y la predominancia creciente de la ideología liberal, contribuyeron a gestar un ambiente cultural propicio para que un individuo con las dotes de Picado pudiera desarrollar sus potencialidades. Se analizan en este sentido el papel que jugaron las cambios en la filosofía educativa, la influencia de los primeros estudiosos de nuestra Historia Natural y los efectos de la temprana efervescencia de nuestra narrativa. Como segunda etapa, se enfatiza la importancia que ejercieron en Picado sus años de estudio en Francia, en la medida en que le permitieron asimilar una serie de aspectos altamente novedosos de la Biología, sobre todo en lo que respecta al empleo del método experimental y al análisis químico, aparejados éstos con los métodos más tradicionales de Historia Natural. Se concluye que la combinación de las influencias recibidas en estas dos etapas de su formación, unidas al talento y vocación excepcionales de Clorito Picado, sentaron las bases de su mentalidad científica y humanista.UCR::Vicerrectoría de Investigació

Antivenomics of Atropoides mexicanus and Atropoides picadoi snake venoms: Relationship to the neutralization of toxic and enzymatic activities

Viperid snakes of the genus Atropoides are distributed in Mexico and Central America and, owing to their size and venom yield, are capable of provoking severe envenomings in humans. This study evaluated, using an ‘antivenomics’ approach, the ability of a polyspecific (polyvalent) antivenom manufactured in Costa Rica to recognize the proteins of Atropoides mexicanus and A. picadoi venoms, which are not included in the immunization mixture. In addition, the neutralization of lethal, hemorrhagic, myotoxic, coagulant, proteinase and phospholipase A2 (PLA2) activities of these venoms by the antivenom was assessed. The antivenom was highly-effective in immunodepleting many venom components, particularly high molecular mass P-III metalloproteinases (SVMPs), L-amino acid oxidases, and some serine proteinases and P-I SVMPs. In contrast, PLA2s, certain serine proteinases and P-I SVMPs, and a C type lectin-like protein were only partially immunodepleted, and two PLA2 molecules were not depleted at all. The antivenom was able to neutralize all toxic and enzymatic activities tested, although neutralization of lethality by A. nummifer venom was achieved when a challenge dose of 3 LD50s of venom was used, but was iffective when 4 LD50s were used. These results, and previously obtained evidence on the immunoreactivity of this antivenom towards homologous and heterologous venoms, revealed the low immunogenicity of a number of venom components (PLA2s, CRISPs, P-I SVMPs, and some serine proteinases), underscoring the need to search for innovative immunization protocols to improve the immune response to these antigens

Electrochemical Behavior Zn(II) at Carbon Steel Electrode in Deep Eutectic Solvents Based on Choline Chloride

Producción CientíficaDeep eutectic solvents prepared by mixture of choline chloride with urea, thiourea and ethylene glycol (1:2 molar ratio) were used to study the electrochemical behavior Zn(II) at carbon steel 1018 electrode. Zn deposits were immersed in a corrosive media (NaCl 3%wt). Composition of the solvent employed causes a difference in electrodeposition and corrosion behaviors, being diffusion coefficient value a critical parameter associated to these processes

Colorimetric analysis for on-line arc-welding diagnostics by means of plasma optical spectroscopy

In this paper an analysis on the suitability of employing a colorimetric analysis of the acquired plasma spectra to perform on-line arc-welding quality monitoring will be discussed. Different colorimetric parameters like the color temperature or the parameters associated with the hue, saturation, luminance color space will be evaluated in comparison with the standard approach based on the estimation of the plasma electronic temperature. This approach does not require the identification of the emission lines involved in the analysis, thus giving rise to a more efficient solution in terms of computational efficiency, and avoiding unambiguous identifications that may give rise to incorrect results. In particular, experimental tests performed with a tungsten inert gas arc-welding process will show the feasibility of using the proposed solution and its ability to perform an online detection of different welding perturbations.This work has been supported by the project TEC2013-47264-C2-1-R

Laser metal deposition on-line monitoring via plasma emission spectroscopy and spectral correlation techniques

Plasma spectroscopic techniques focused on the analysis of the plasma background radiation have been studied to enable an efficient on-line monitoring of a laser metal deposition process. The influence of different process parameters and elements, such as laser power, process speed, powder feeding rate and different powder and substrate compositions has been analyzed by means of several experimental trials. The resulting cladding patch analyzes via visual inspection and macrographs have been correlated with their associated spectroscopic monitoring signals. These studies have indicated that on-line quality monitoring of the laser metal deposition process is feasible by means of the proposed solutions, avoiding the identification and use of plasma emission lines. The latter improves the computational performance and avoids, not only the identification of each emission line, but also their specific sensitivity to certain defects. Spectral correlation techniques have also been proposed for monitoring purposes, thus enabling a more quantitative analysisThis work was supported in part by the Project “Noves tecnologies de laser cladding per a processos de conformat” (RD15-1-0098) funded by ACCIO (Generalitat de Catalunya) via FEDER funds. This work was also supported by projects PID2019-107270RB-C21/ AEI / 10.13039/501100011033

An inertial sensor-based system designed to measure and prevent undesired camera rotation during endoscopic sinus surgery

This project was developed thanks to the Innovation Support Program “InnVal” of the Marqués de Valdecilla Research Institute (IDIVAL)

Effect of Deep Eutectic Solvent Composition on the Corrosion Behavior of Electrodeposited Cadmium Coatings on Carbon Steel

Producción CientíficaDeep eutectic solvents prepared by mixing choline chloride with urea or thiourea (1:2 molar ratio) were employed to evaluate their effects on the formation of cadmium electrodeposits on a reactive electrode composed of carbon steel 1018. The corrosion protection of carbon steel corresponds to the use of cadmium as a sacrificial anode. Differences in DES affect the electrochemical and corrosion behavior of cadmium.Junta de Castilla y Leon (Project VA171U14

Estimation of the plasma spectrum RMS signal as an alternative spectroscopic approach for arc-welding quality monitoring

Plasma spectroscopy has demonstrated its potential within the framework of welding process quality monitoring. The analysis of the welding plasma spectrum, which is formed by several emission lines from the different elements participating in the process, gives rise to spectroscopic parameters exhibiting a direct correlation to the quality of the resulting seams. The plasma electronic temperature has been the traditional selection in this regard, mainly by using an approximation where only two emission lines from the same species are involved in the calculations. However, for a completely automated system, the computational cost involved in the process could be a serious drawback. In this paper we propose the use of the plasma spectrum RMS (Root Mean Square) signal as an alternative spectroscopic approach, as it will be demonstrated that this parameter can be also used to identify the appearance of weld defects in an on-line quality monitoring system

Spectroscopic Polymer Optical Fiber sensor for orbital arc-welding on-line monitoring

Plasma optical spectroscopy has proved to be a promising solution for the on-line monitoring of both laser and arc-welding processes, where quality assurance plays a mayor role, especially in some particular industrial scenarios like aeronautics. Despite the robustness provided by these spectroscopic analysis techniques, the implementation of an efficient and non-invasive optical sensor system is not always feasible. Input optics based on optical collimators are commonly employed, but when complex shapes are to be welded, or specific welding processes are being considered, a different approach must be designed. In this paper we propose an optical sensor based on the use of a Polymer Optical Fiber (POF) as the input optics. The external protection of the POF is removed, providing an acquisition of the plasma radiation from the fiber cladding. Experimental welding tests will show the feasibility of the proposed POF sensor

Real-time detection of the aluminium contribution during laser welding of Usibor1500 tailor-welded blanks

The identification and intensity estimation of some aluminium emission lines have been proposed to perform an on-line quantification of the Al contribution to the laser-welding process of Usibor blanks. This boron steel is protected by an Al-Si coating that is removed by laser ablation before welding. If this process fails to remove Al from the joint surface, its contribution may affect the final properties of the resulting seams, therefore compromising their quality. Experimental tests have been performed, some of them in a real production scenario. They have been analysed and compared to the results of welding test specimens, analysis of the associated tensile properties and fracture locations and seam macrographs. These studies have indicated that on-line quantification of the Al contribution to the process is feasible and that a correlation can be established between the Al content estimated in real-time and the results derived from the off-line tests considered.The authors would like to thank the staff of Autotech Engineering and Solblank (both Gestamp companies) for their valuable help during the design, implementation and test of the monitoring system. This work has been supported by the project TEC2013- 47264-C2-1-