Protein crops: Food and feed for the future [Editorial]

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Automatic classification system of Raman spectra applied to pigments analysis

Raman spectroscopy is one of the few non-destructive techniques capable of identifying pigments in art works. Raman spectra contain powerful information that can be used to identify unknown compounds and their chemical structures. However, the analysis of spectral data comes with some difficulties, and therefore the spectral interpretation is not straightforward. Sometimes, there are very little differences in the spectral data concerning to specific identification objectives, for instance, in polymorphic discrimination or in the discrimination of natural and synthetic forms of certain pigments. Moreover, this discrimination is often performed manually so that the process can be repetitive, subjective and particularly time-consuming. The result is an increasing motivation to automate the identification process involved in the classification of pigments in paint. In this paper, we propose a system to automatically classify the spectral data into specific and well-known classes, i.e. reference classes. The proposal is based on a combination of chemometric techniques, which provides a powerful way to achieve spectral separability so that it is possible to discriminate between very similar spectra in an automatic way. In this regard, a decision-making algorithm was specifically developed to select the corresponding reference class with no user input, which was successfully validated using simulated spectra. The implemented methodology was used to classify Raman spectra of pigments commonly present in artist's paints in experimental cases, providing reliable and consistent results. Therefore, the presented system can play a good auxiliary role in the analysts' endpoint classification.Peer ReviewedPostprint (author's final draft

A non-parametric analysis of convergence in ICT industries

The purpose of this article is to explore the relative merits of capital accumulation and efficiency catch-up in the convergence patterns of labor productivity in theICT (Information and Communication Technologies) sector in a set of developed countries. It is the first convergence analysis of ICT carried out from the non-parametric kernel approach and using an intertemporal data envelopment analysis (DEA) to estimate the efficiency of the analyzed countries. Special care has been paid to the dataset construction, using hedonic prices and unit value ratios because of the nature of the industry. The appropriate technology theory extended with non-immediate spillovers is the theoretical framework used to interpret the obtained results. These show thatlabor productivity, technology and efficiency have moved from a unimodal towards a bimodal distribution over time, beginning the 21th century with two convergence clubs of countries. The conclusions obtained from these results show that while capital intensification offer opportunities to benefit from new knowledge developed by the leaders, assimilation of this knowledge is not immediate and its speed depends upon the social and technological capabilities of the followers. Policy decision-makers should be aware that the choice of the technology has to be complemented with the development of other actives to benefit from all its potentialities

Melatonin to rescue the aged heart: antiarrhythmic and antioxidant benefits

Aging comes with gradual loss of functions that increase the vulnerability to disease, senescence, and death. The mechanisms underlying these processes are linked to a prolonged imbalance between damage and repair. Damaging mechanisms include oxidative stress, mitochondrial dysfunction, chronodisruption, inflammation, and telomere attrition, as well as genetic and epigenetic alterations. Several endogenous tissue repairing mechanisms also decrease. These alterations associated with aging affect the entire organism. The most devastating manifestations involve the cardiovascular system and may lead to lethal cardiac arrhythmias. Together with structural remodeling, electrophysiological and intercellular communication alterations during aging predispose to arrhythmic events. Despite the knowledge on repairing mechanisms in the cardiovascular system, effective antiaging strategies able to reduce the risk of arrhythmias are still missing. Melatonin is a promising therapeutic candidate due to its pleiotropic actions. This indoleamine regulates chronobiology and endocrine physiology. Of relevance, melatonin is an antiaging, antioxidant, antiapoptotic, antiarrhythmic, immunomodulatory, and antiproliferative molecule. This review focuses on the protective effects of melatonin on age-induced cardiac functional and structural alterations, potentially becoming a new fountain of youth for the heart

Sedimentology and paleontology of the lower member of the Nogueras Fm (Lower Devonian) at Santa Cruz de Nogueras (Teruel, NE Spain)

An integrated sedimentological and paleontological analysis has been canted out in the lower member (d2a) of the shallow-marine Nogueras Formation (Lower Devonian, Iberian Chains). This formation represents the first carbonate-dominated and fossil-rich sedimentary unit of the Devonian of the Iberian Chains. Nine sedimentary facies, including terrigenous-clastic, mixed and carbonate facies, which are complexly intercalated at bed scale, have been characterized. Based on their sedimentary features and their lateral relationships using Markov chain analysis, two sedimentary models for the lower and upper part of d2a member have been proposed, which represent deposition in a mixed elastic-carbonate shallow marine depositional system. They include terrigenous-clastic intertidal deposits and predominant skeletal, carbonate-dominated and grain-supported facies in the high-energy shallow subtidal zone, whith a clear zonation of the skeletal components (brachiopods, bryozoans and crinoids, from shallow to relatively deep areas). Phosphate nodules, phosphatized fossils, ferruginous crusts and iron ooids, which are frequently associated with the relatively shallower bioclastic brachiopod facies, were probably linked to mineral continental sources and to remobilization in the shallow water high-energy area. The paleontological analysis shows that some of those organisms lived in protected areas of the subtidal zone, including in particular high-diversity communities of brachiopods, adapted to turbid waters with fine terrigenous suspended sediments. Se ha realizado un análisis sedimentológico y paleontológico integrado del miembro inferior (d2a) de la Formación Nogueras, que representa la primera unidad marina somera predominantemente carbonatada del Devónico de las Cadenas Ibéricas. Se han definido nueve facies sedimentarias tcrrígeno-clás ticas, mixtas y carbonatadas, que están complejamente intercaladas a escala de capa, depositadas en un sistema mixto de- trítico-carbonatado de aguas someras. En Junción de sus rasgos sedimentarios y del análisis de sus relaciones laterales mediante cadenas de Markov, se proponen dos modelos sedimentarios para la parte inferior y superior del miembro estudiado. Los dos modelos incluyen depósitos terrígenos en la zona intermareal y facies carbonatadas bioclásticas en la zona submareal somera, con una clara zonación de sus componentes esqueléticos dominantes (braquiópodos, briozoos, crinoides, desde la zona somera a la relativamente profunda). Los nodulos de fosfato, fósiles fósfatizados, costras y ooides ferruginosas frecuentes en las facies bioclasticas de braquiópodos relativamente someras, se relacionaron probablemente con aportes minerales desde el continente y retrabajamiento en la zona marina de alta energía. El análisis paleontológico muestra que algunos de estos organismos vivían en áreas protegidas de la zona submareal, incluyendo particularmente comunidades con alta diversidad de braquiópodos, adaptadas a aguas turbias con elevado sedimento terrígeno fino en suspensión

A Time-Varying Non-Parametric Methodology for Assessing Changes in QT Variability Unrelated to Heart Rate Variability

OBJECTIVE: To propose and test a novel methodology to measure changes in QT interval variability (QTV) unrelated to RR interval variability (RRV) in non-stationary conditions. METHODS: Time-frequency coherent and residual spectra representing QTV related (QTVrRRV) and unrelated (QTVuRRV) to RRV, respectively, are estimated using time-frequency Cohen's class distributions. The proposed approach decomposes the non-stationary output spectrum of any two-input one-output model with uncorrelated inputs into two spectra representing the information related and unrelated to one of the two inputs, respectively. An algorithm to correct for the bias of the time-frequency coherence function between QTV and RRV is proposed to provide accurate estimates of both QTVuRRV and QTVrRRV. Two simulation studies were conducted to assess the methodology in challenging non-stationary conditions and data recorded during head-up tilt in 16 healthy volunteers were analyzed. RESULTS: In the simulation studies, QTVuRRV changes were tracked with only a minor delay due to the filtering necessary to estimate the non-stationary spectra. The correlation coefficient between theoretical and estimated patterns was >0.92 even for extremely noisy recordings (SNR in QTV =-10dB). During head-up tilt, QTVrRRV explained the largest proportion of QTV, whereas QTVuRRV showed higher relative increase than QTV or QTVrRRV in all spectral bands (P<0.05 for most pairwise comparisons). CONCLUSION: The proposed approach accurately tracks changes in QTVuRRV. Head-up tilt induced a slightly greater increase in QTVuRRV than in QTVrRRV. SIGNIFICANCE: The proposed index QTVuRRV may represent an indirect measure of intrinsic ventricular repolarization variability, a marker of cardiac instability associated with sympathetic ventricular modulation and sudden cardiac death

Automatic identification of artistic pigments by Raman spectroscopy using fuzzy logic and principal component analysis

This work offers an automatic identification system of Raman spectra of artistic pigments. The proposed methodology is based on a fuzzy logic system, and uses principal component analysis to reduce redundancies in data and the correlation operator as an index of similarity between two Raman spectra. Moreover, as sometimes pigments are used in mixtures by artist, the designed system is able to recognize binary mixtures of pigments on the basis of their Raman fingerprints.Peer ReviewedPostprint (published version