Two-sided bounds and perturbation results for regularized determinants of infinite order compact operators

AbstractA compact operator in a separable Hilbert space is of infinite order if it does not belong to any Schatten–von Neumann ideal. In the paper, upper and lower bounds for the regularized determinants of infinite order operators are derived. By these bounds, perturbations results for the regularized determinants are established

Bounds for characteristic values of entire matrix pencils

AbstractEntire matrix-valued functions of a complex argument (entire matrix pencils) are considered. Upper bounds for sums of characteristic values and a lower bound for the smallest characteristic value are derived in the terms of the coefficients of the Taylor series. These results are new even for polynomial pencils

Exploring Corporate Social Responsibility under the Background of Sustainable Development Goals: A Proposal to Corporate Volunteering

The research into corporate volunteering (CV) has been prolific, although few studies have focused their approach on senior and retired workers under the framework of the corporate social responsibility (CSR). The social participation of retirees in CV activities contributes to the businesses'' socially responsible performance and can be intimately connected with the global commitment pursued by the Sustainable Development Goals (SDGs) by the year 2030. This article aims to explore the key issues that might have influence the effective implementation of CV programs to integrate retired and pre-retired workers, promoting a participatory and healthy aging. Based on the interface of internal and external corporate social responsibility, we discuss how CV can achieve social legitimacy, influencing the health and well-being of workers beyond the employment relationship. The main contribution of this article to the state of art is to extend the literature on CSR and CV by elaborating a theoretical model that integrates both perspectives with the focus on the SDGs. The results suggest that SDGs represent an opportunity and a frame of reference for CSR strategies. Companies engaged in senior CV activities could enhance their corporate and social images within the strategic action of social responsibility, indisputably improving people''s health and well-being

Corporate Volunteering: a Tool for Promoting a Strategy for Internal Corporate Social Responsibility Integrating Retirees

This paper aims to make an exploratory analysis of the effectiveness of implementing a Corporate Volunteering program aimed at the context of retired workers, as a tool for participatory and healthy aging. The research study focused on the importance of the social participation of retirees in a company as a priority interest for the development of Corporate Volunteering programs, and delved into the expression of the socially responsible performance of organizations in volunteering actions carried out by their retired employees. Results show that the performance of retirees in a company’s volunteering activities can count on intimately connected theoretical supports and is closely related to Corporate Social Responsibility, fostering an active, healthy and fair old age, with socialbenefit to the community

Quality classification of Spanish olive oils by untargeted gas chromatography coupled to hybrid quadrupole–time of flight mass spectrometry with atmospheric pressure chemical ionization and metabolomics-based statistical approach

The novel atmospheric pressure chemical ionization (APCI) source has been used in combination with gas chromatography (GC) coupled to hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) for determination of volatile components of olive oil, enhancing its potential for classification of olive oil samples according to their quality using a metabolomics-based approach. The full-spectrum acquisition has allowed the detection of volatile organic compounds (VOCs) in olive oil samples, including extra virgin, virgin and lampante qualities. A dynamic headspace extraction with cartridge solvent elution was applied. The metabolomics strategy consisted of three different steps: a full mass spectral alignment of GC-MS data using MzMine 2.0, a multivariate analysis using Ez-Info and the creation of the statistical model with combinations of responses for molecular fragments. The model was finally validated using blind samples, obtaining an accuracy in oil classification of 70 % taking the official established method, “PANEL TEST” as reference.The authors acknowledge the financial support of Generalitat Valenciana, as research group of excellence (PROMETEO II/2014/023) and Collaborative Research on Environment and Food-Safety (ISIC/2012/016). This work and C. Sales grant has been supported by Universitat Jaume I research promotion plans (P1-1B2013-70

In vivo selection of Plasmodium falciparum parasites carrying the chloroquine-susceptible pfcrt K76 allele after treatment with artemether-lumefantrine in Africa

Background: Artemether-lumefantrine (AL) is a major and highly effective artemisinin-based combination therapy that is becoming increasingly important as a new first-line therapy against Plasmodium falciparum malaria. However, recrudescences occurring after AL treatment have been reported. Identification of drug-specific parasite determinants that contribute to treatment failures will provide important tools for the detection and surveillance of AL resistance. Methods: The findings from a 42-day follow-up efficacy trial in Tanzania that compared AL with sulfadoxinepyrimethamine (SP) were analyzed to identify candidate markers for lumefantrine tolerance/resistance in the chloroquine resistance transporter gene (pfcrt) and multidrug resistance gene 1 (pfmdr1). The findings were corroborated in vitro with genetically modified isogenic P. falciparum parasite lines. Results: Treatment with AL selected for the chloroquine-susceptible pfcrt K76 allele (P \u3c .0001) and, to a lesser extent, the pfmdr1 N86 (P = .048) allele among recurrent infections. These genotypes were not selected during SP treatment. No pfmdr1 gene amplifications were observed. Isogenic pfcrt-modified parasite lines demonstrated a 2-fold increase in susceptibility to lumefantrine, which was directly attributable to the K76T mutation. Conclusions: Our findings suggest that the pfcrt K76T mutation is a drug-specific contributor to enhanced P. falciparum susceptibility to lumefantrine in vivo and in vitro, and they highlight the benefit of using AL in areas affected by chloroquine-resistant P. falciparum malaria. © 2009 by the Infectious Diseases Society of America. All rights reserved

Hyperspectral imaging to evaluate the effect of irrigation water salinity in lettuce

International audienceSalinity is one of the most important stress factors in crop production, particularly in arid regions. This research focuses on the effect of salinity on the growth of lettuce plants; three solutions with different levels of salinity were considered and compared (S1 = 50, S2 = 100 and S3 = 150 mM NaCl) with a control solution (Ct = 0 mM NaCl). The osmotic potential and water content of the leaves were measured, and hyperspectral images of the surfaces of 40 leaves (10 leaves per treatment) were taken after two weeks of growth. The mean spectra of the leaves (n = 32,000) were pre-processed by means of a Savitzky-Golay algorithm and standard normal variate normalization. Principal component analysis was then performed on a calibration set of 28 mean spectra, yielding an initial model for salinity effect detection. A second model was subsequently proposed based on an index computing an approximation to the second derivative at the red edge region. Both models were applied to all the hyperspectral images to obtain the corresponding artificial images, distinguishing between the 28 that were used to extract the calibration mean spectra and the rest that constituted an external validation. Those virtual images were studied using analysis of variance in order to compare their ability for detecting salinity effects on the leaves. Both models showed significant differences between each salinity level, and the hyperspectral images allowed observations of the distribution of the salinity effects on the leaf surfaces, which were more intense in the areas distant from the veins. However, the index-based model is simpler and easier to apply because it is based solely on the reflectance at three different wavelengths, thus allowing for the implementation of less expensive multispectral devices

A novel electrochemical device as a disinfection system to maintain water quality during washing of ready to eat fresh produce

Electrolyzed water (EW) is known by its bactericidal efficacy and capability to oxidize organic matter. The present research evaluated the efficacy of recently developed electrolytic cells able to generate higher concentration of reactive oxygen species using lower power and salt concentration than conventional cells. This study tested the inactivation of Escherichia coli O157:H7, the organic matter depletion and trihalomethane (THM) generation by EW in process wash water under dynamic conditions. To achieve this, clean tap water was continuously added up to 60 min with artificial process water with high chemical oxygen demand (COD) inoculated with E. coli O157:H7, in experiments performed in a pilot plant that recirculated water through one electrolytic cell. Plate counts of E. coli O157:H7, COD, THMs, free, combined and total chlorine, pH, temperature and oxidation-reduction potential were determined. Results indicate that the novel electrolysis system combined with minimal addition of NaCl (0.05%) was able to suppress E. coli O157:H7 population build-up and decreased the COD accumulation in the process wash water. THM levels in the water were relatively high but its concentration in the washed product was marginal. Highly effective electrolysis has been proven to reduce the occurrence of foodborne diseases associated to cross-contamination in produce washers without having an accumulation of THMs in the washed product.Ciencias de la Alimentació