Ultrasonic evaluation of the hydration degree of the orange peel

The elastic parameters of fruit and vegetables are normally monitored in quality control processes as there is a good correlation to the degrees of firmness, turgidity and humidity. These parameters have been traditionally measured by means of penetration tests, which are destructive. This has resulted in the increased attention recently given to ultrasonic techniques applied to the quality evaluation of horticultural commodities. Nevertheless, since most of the fruit and vegetables display a viscoelastic behavior, the penetration test should be considered to be quasi-static, especially when compared with the speeds associated with the ultrasonic tests. Both methods should provide different values for the elastic parameters. The aim of this work is to study this discrepancy in the values of the elastic parameters and interpret the elastodynamic behavior of the vegetable tissue under an ultrasound test. Thus, the paper presents an ultrasonic nondestructive method to evaluate the elastic parameters of the sweet orange peel at 40. kHz. The complete dehydration process of two sets of oranges (Navelina and Ortanique) was monitored for 2. months. A linear elastic solid model with viscous losses was numerically solved using a simulation scheme based on a 3D-Spherical FDTD method (Finite-Difference Time-Domain) in order to interpret the results, which proved that the elastic parameters obtained by penetration and ultrasonic tests differ. The method provides an empirical relation between the hydration state and the elastic parameters of the orange peel. Therefore, the proposed ultrasonic test reported in this work is capable of determining the hydration state of the orange simply by measuring the propagation speed of the Rayleigh waves on the orange peel, and hence, can be used as a fruit quality index during postharvest processes. © 2012 Elsevier B.V.This study was supported by the Programa de Apoyo a la Investigacion y Desarrollo (PAID-05-09-002-618), (PAID-06-10-002-295) of Universidad Politecnica de Valencia. The authors would like to thank K. Y. Foo, from the University of Birmingham and P. Malischewsky from the University Friedrich-Schiller at Jena, for the fruitful discussions regarding surface acoustic waves.Jimenez, N.; Picó Vila, R.; Camarena Femenia, F.; Redondo, J.; Roig, B. (2012). Ultrasonic evaluation of the hydration degree of the orange peel. Postharvest Biology and Technology. 67:130-137. https://doi.org/10.1016/j.postharvbio.2011.12.020S1301376

Inhibitory Effect of Azamacrocyclic Ligands on Polyphenol Oxidase in Model and Food Systems

This document is the unedited Author's version of a Submitted Work that was subsequently accepted for publication in Journal of Agricultural and Food Chemistry, copyright © American Chemical Society after peer review. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acs.jafc.0c02407[EN] Enzymatic browning is one of the main problems faced by the food industry due to the enzyme polyphenol oxidase (PPO) provoking an undesirable color change in the presence of oxygen. Here, we report the evaluation of 10 different azamacrocyclic compounds with diverse morphologies as potential inhibitors against the activity of PPO, both in model and real systems. An initial screening of 10 ligands shows that all azamacrocyclic compounds inhibit to some extent the enzymatic browning, but the molecular structure plays a crucial role on the power of inhibition. Kinetic studies of the most active ligand (L2) reveal a S-parabolic I-parabolic noncompetitive inhibition mechanism and a remarkable inhibition at micromolar concentration (IC50 = 10 mu M). Furthermore, L2 action has been proven on apple juice to significantly reduce the enzymatic browning.Financial support by the Spanish Ministerio de Ciencia, Innovacion y Universidades (project RTI2018-100910-B-C44), Ministerio de Economia y Competitividad (projects CTQ2016-78499-C6-1-R, Unidad de Excelencia MDM 2015-0038 and CTQ2017-90852-REDC), and Generalitat Valenciana (Project PROMETEOII2015-002) is gratefully acknowledged.Muñoz-Pina, S.; Ros-Lis, JV.; Delgado-Pinar, E.; Martínez-Camarena, Á.; Verdejo, B.; García-España, E.; Argüelles Foix, AL.... (2020). Inhibitory Effect of Azamacrocyclic Ligands on Polyphenol Oxidase in Model and Food Systems. Journal of Agricultural and Food Chemistry. 68(30):7964-7973. https://doi.org/10.1021/acs.jafc.0c02407796479736830Simpson, B. K. (Ed.). (2012). 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Journal of Agricultural and Food Chemistry, 58(18), 10076-10084. doi:10.1021/jf1015347Massini, L., Rico, D., & Martin-Diana, A. B. (2018). Quality Attributes of Apple Juice. Fruit Juices, 45-57. doi:10.1016/b978-0-12-802230-6.00004-7McEvily, A. J., Iyengar, R., & Otwell, W. S. (1992). Inhibition of enzymatic browning in foods and beverages. Critical Reviews in Food Science and Nutrition, 32(3), 253-273. doi:10.1080/10408399209527599Iyengar, R., & McEvily, A. J. (1992). Anti-browning agents: alternatives to the use of sulfites in foods. Trends in Food Science & Technology, 3, 60-64. doi:10.1016/0924-2244(92)90131-fMuñoz-Pina, S., Ros-Lis, J. V., Argüelles, Á., Coll, C., Martínez-Máñez, R., & Andrés, A. (2018). Full inhibition of enzymatic browning in the presence of thiol-functionalised silica nanomaterial. Food Chemistry, 241, 199-205. doi:10.1016/j.foodchem.2017.08.059Muñoz-Pina, S., Ros-Lis, J. V., Argüelles, Á., Martínez-Máñez, R., & Andrés, A. (2020). Influence of the functionalisation of mesoporous silica material UVM-7 on polyphenol oxidase enzyme capture and enzymatic browning. Food Chemistry, 310, 125741. doi:10.1016/j.foodchem.2019.125741Castillo, C. E., Máñez, M. A., Basallote, M. G., Clares, M. P., Blasco, S., & García-España, E. (2012). Copper(ii) complexes of quinoline polyazamacrocyclic scorpiand-type ligands: X-ray, equilibrium and kinetic studies. Dalton Transactions, 41(18), 5617. doi:10.1039/c2dt30223cSantra, S., Mukherjee, S., Bej, S., Saha, S., & Ghosh, P. (2015). Amino-ether macrocycle that forms CuII templated threaded heteroleptic complexes: a detailed selectivity, structural and theoretical investigations. Dalton Transactions, 44(34), 15198-15211. doi:10.1039/c5dt00596eFan, R., Serrano-Plana, J., Oloo, W. N., Draksharapu, A., Delgado-Pinar, E., Company, A., … Münck, E. (2018). Spectroscopic and DFT Characterization of a Highly Reactive Nonheme FeV–Oxo Intermediate. Journal of the American Chemical Society, 140(11), 3916-3928. doi:10.1021/jacs.7b11400Martínez-Camarena, Á., Liberato, A., Delgado-Pinar, E., Algarra, A. G., Pitarch-Jarque, J., Llinares, J. M., … García-España, E. (2018). Coordination Chemistry of Cu2+ Complexes of Small N-Alkylated Tetra-azacyclophanes with SOD Activity. Inorganic Chemistry, 57(17), 10961-10973. doi:10.1021/acs.inorgchem.8b01492Algarra, A. G., Basallote, M. G., Belda, R., Blasco, S., Castillo, C. E., Llinares, J. M., … Verdejo, B. (2009). Synthesis, Protonation and CuIIComplexes of Two Novel Isomeric Pentaazacyclophane Ligands: Potentiometric, DFT, Kinetic and AMP Recognition Studies. European Journal of Inorganic Chemistry, 2009(1), 62-75. doi:10.1002/ejic.200800576Díaz, P., Basallote, M. G., Máñez, M. A., García-España, E., Gil, L., Latorre, J., … Luis, S. V. (2003). Thermodynamic and kinetic studies on the Cu2+ coordination chemistry of a novel binucleating pyridinophane ligandElectronic supplementary information (ESI) available: Table S1: observed rate constants for the acid-promoted decomposition of Cu2+ complexes with ligand L. Table S2: observed rate constants for the acid-promoted decomposition of Cu2+ complexes with macrocycle L1. Fig. S1: Variation of some selected 13C chemical shifts as a function of pH. See http://www.rsc.org/suppdata/dt/b2/b209013a/. Dalton Transactions, (6), 1186-1193. doi:10.1039/b209013aBasallote, M. G., Doménech, A., Ferrer, A., García-España, E., Llinares, J. M., Máñez, M. A., … Verdejo, B. (2006). Synthesis and Cu(II) coordination of two new hexaamines containing alternated propylenic and ethylenic chains: Kinetic studies on pH-driven metal ion slippage movements. 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Recent Developments in the Stereoselective Synthesis of Nitrogen-Containing Heterocycles usingN-Acylimines as Reactive Substrates. Advanced Synthesis & Catalysis, 358(23), 3657-3682. doi:10.1002/adsc.201600644Liu, W., Zou, L., Liu, J., Zhang, Z., Liu, C., & Liang, R. (2013). The effect of citric acid on the activity, thermodynamics and conformation of mushroom polyphenoloxidase. Food Chemistry, 140(1-2), 289-295. doi:10.1016/j.foodchem.2013.02.028Son, S. M., Moon, K. D., & Lee, C. Y. (2000). Kinetic Study of Oxalic Acid Inhibition on Enzymatic Browning. Journal of Agricultural and Food Chemistry, 48(6), 2071-2074. doi:10.1021/jf991397xÖZ, F., COLAK, A., ÖZEL, A., SAĞLAM ERTUNGA, N., & SESLI, E. (2011). PURIFICATION AND CHARACTERIZATION OF A MUSHROOM POLYPHENOL OXIDASE AND ITS ACTIVITY IN ORGANIC SOLVENTS. Journal of Food Biochemistry, 37(1), 36-44. doi:10.1111/j.1745-4514.2011.00604.xAyaz, F. A., Demir, O., Torun, H., Kolcuoglu, Y., & Colak, A. (2008). 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Hybrid learning environments in graduate studies

presente trabajo fue realizado por un equipo de académicas que formamos parte del núcleo básico de profesores de la Maestría en Gestión y Desarrollo Social, de la Universidad de Guadalajara. Nos interesa realizar una propuesta educativa que apoye los procesos de enseñanza y aprendizaje en el actual escenario y que responda a entender y atender las situaciones de incertidumbre tales como las que estamos viviendo ante la crisis sanitaria que originó la pandemia causada por el virus SARS-COV 2. Para ello, conjuntamos nuestros diferentes puntos de vista para integrar una propuesta de Modelo Híbrido de Enseñanza bajo el cual ejercer la docencia en el posgrado en comento, partiendo de la recreación de nuestras prácticas educativas y renovándolas de cara al futuro Post Pandemia que, a nuestro juicio, no regresará a la llamada normalidad del pasado. La nueva normalidad deberá estar constituida por nuevas formas de percibir, pensar, crear y actuar en los diferentes escenarios de la vida que se han visto en la necesidad de recrearse con motivo de la emergencia, pero profundamente cimentada en las innovaciones surgidas en la teoría pedagógica (andragógica, en nuestro caso), metodológicas, didácticas y tecnológicas aplicables a la educación, campo que durante tantas décadas se mostró reacio al cambio.The present work was carried out by a team of academics that are part of the basic core of professors of the Master in Management and Social Development, of the University of Guadalajara. We are interested in making an educational proposal that supports the teaching and learning processes in the current scenario and responds to understand and address situations of uncertainty such as those we are experiencing in the face of the health crisis that caused the pandemic caused by the SARS-COV virus. 2. For this, we combine our different points of view to integrate a proposal for a Hybrid Model of Teaching under which to teach in the postgraduate course in question, starting from the recreation of our educational practices and renewing them for the future Post Pandemic that, in our judgment, it will not return to the so-called normality of the past. The new normality must be constituted by new ways of perceiving, thinking, creating and acting in the different scenarios of life that have been in need of recreation due to the emergency, but deeply grounded in the innovations that emerged in pedagogical theory (andragogic, in our case), methodological, didactic and technological applicable to education, a field that for so many decades was reluctant to change.Facultad de Informátic

Status and Recent Results of the Acoustic Neutrino Detection Test System AMADEUS

The AMADEUS system is an integral part of the ANTARES neutrino telescope in the Mediterranean Sea. The project aims at the investigation of techniques for acoustic neutrino detection in the deep sea. Installed at a depth of more than 2000m, the acoustic sensors of AMADEUS are based on piezo-ceramics elements for the broad-band recording of signals with frequencies ranging up to 125kHz. AMADEUS was completed in May 2008 and comprises six "acoustic clusters", each one holding six acoustic sensors that are arranged at distances of roughly 1m from each other. The clusters are installed with inter-spacings ranging from 15m to 340m. Acoustic data are continuously acquired and processed at a computer cluster where online filter algorithms are applied to select a high-purity sample of neutrino-like signals. 1.6 TB of data were recorded in 2008 and 3.2 TB in 2009. In order to assess the background of neutrino-like signals in the deep sea, the characteristics of ambient noise and transient signals have been investigated. In this article, the AMADEUS system will be described and recent results will be presented.Comment: 7 pages, 8 figures. Proceedings of ARENA 2010, the 4th International Workshop on Acoustic and Radio EeV Neutrino Detection Activitie

The ANTARES Telescope Neutrino Alert System

The ANTARES telescope has the capability to detect neutrinos produced in astrophysical transient sources. Potential sources include gamma-ray bursts, core collapse supernovae, and flaring active galactic nuclei. To enhance the sensitivity of ANTARES to such sources, a new detection method based on coincident observations of neutrinos and optical signals has been developed. A fast online muon track reconstruction is used to trigger a network of small automatic optical telescopes. Such alerts are generated for special events, such as two or more neutrinos, coincident in time and direction, or single neutrinos of very high energy.Comment: 17 pages, 9 figures submitted to Astroparticle Physic

Hadron Energy Reconstruction for the ATLAS Calorimetry in the Framework of the Non-parametrical Method

This paper discusses hadron energy reconstruction for the ATLAS barrel prototype combined calorimeter (consisting of a lead-liquid argon electromagnetic part and an iron-scintillator hadronic part) in the framework of the non-parametrical method. The non-parametrical method utilizes only the known $e/h$ ratios and the electron calibration constants and does not require the determination of any parameters by a minimization technique. Thus, this technique lends itself to an easy use in a first level trigger. The reconstructed mean values of the hadron energies are within $\pm 1$ of the true values and the fractional energy resolution is $[(58\pm3)/\sqrt{E}+(2.5\pm0.3)$. The value of the $e/h$ ratio obtained for the electromagnetic compartment of the combined calorimeter is $1.74\pm0.04$ and agrees with the prediction that $e/h > 1.7$ for this electromagnetic calorimeter. Results of a study of the longitudinal hadronic shower development are also presented. The data have been taken in the H8 beam line of the CERN SPS using pions of energies from 10 to 300 GeV.Comment: 33 pages, 13 figures, Will be published in NIM

Acoustic and optical variations during rapid downward motion episodes in the deep north-western Mediterranean Sea

An Acoustic Doppler Current Profiler (ADCP) was moored at the deep-sea site of the ANTARES neutrino telescope near Toulon, France, thus providing a unique opportunity to compare high-resolution acoustic and optical observations between 70 and 170 m above the sea bed at 2475 m. The ADCP measured downward vertical currents of magnitudes up to 0.03 m s-1 in late winter and early spring 2006. In the same period, observations were made of enhanced levels of acoustic reflection, interpreted as suspended particles including zooplankton, by a factor of about 10 and of horizontal currents reaching 0.35 m s-1. These observations coincided with high light levels detected by the telescope, interpreted as increased bioluminescence. During winter 2006 deep dense-water formation occurred in the Ligurian subbasin, thus providing a possible explanation for these observations. However, the 10-20 days quasi-periodic episodes of high levels of acoustic reflection, light and large vertical currents continuing into the summer are not direct evidence of this process. It is hypothesized that the main process allowing for suspended material to be moved vertically later in the year is local advection, linked with topographic boundary current instabilities along the rim of the 'Northern Current'.Comment: 30 pages, 7 figure