1,578 research outputs found

    A REGRESSION MODEL FOR THE TONS OF PRUNING PER HECTARE

    Get PDF
    More than nine million hectares of olive trees are cultivated all over the world, but especially in the Mediterranean countries. As an essential operation, pruning of olive trees produces a huge amount of biomass which is lacking of industrial applications and must be eliminated from fields to prevent propagation of vegetal diseases. This work deals with the development of a regression model to be used in the estimation of the real biomass production from olive tree pruning

    Do one‐step mechanisms always involve simultaneous evolution of electron density? QTAIM/IQA analysis of the Curtius rearrangement

    Get PDF
    The Curtius rearrangement reaction is studied by using quantum theory of atoms in molecules (QTAIM) analysis of the electron density and the interacting quantum atoms (IQA) formalism. Although the rearrangements take place in one stage, two phases are distinguished when the rearranged atom is H: the first one corresponds to the separation of N2, and the second one to the N‐H/C‐H bond rearrangement. The transition state (TS) for the reaction does not represent an intermediate between reagent and product for the migration but for the isolation of the N2 molecule. When the migration is undergone by a fluorine atom, no electronic phases can be distinguished and the process is really concerted. As the migration happens closer to the TS, the TS is more similar to the product. The IQA analysis reveals different electron density evolutions for H and F migrations, and the scarce relevance (in terms of energy) of the point where BCPs appear or disappear.Xunta de Galicia | Ref. ED431C 2019/2

    Microstructure–hardness–corrosion performance of 17–4 precipitation hardening stainless steels processed by selective laser melting in comparison with commercial alloy

    Get PDF
    Producción CientíficaThe 17–4 Precipitation Hardening Stainless Steel (PH SS) manufactured by Selective Laser Melting (SLM) has wide appli- cation perspectives, but they are limited due to defects and anisotropy. The selection of the appropriate process variables plays a fundamental part in the microstructure and in the determination of the final mechanical and corrosion properties. The main purpose of this study is to analyze the corrosion behavior, hardness and microstructure of 17–4 PH SS manufac- tured by SLM in comparison to the commercial counterparts. The anisotropic behavior was investigated by analyzing the microstructure–hardness and corrosion interrelationship, both in the surface of the construction platform and in the growth direction of the element. The corrosion behavior of the SLM 17–4PH SS in its natural state was investigated in relation to that of the 17–4 PH SS heat treated in a 0.1 M NaCl + 0.5 M H 2 SO 4 solution, using three electrochemical techniques. The results confirmed that the corrosion resistance of SLM 17–4 PH SS was considerably better than that of the forging, even after 60 days of immersion in the test solution. This was attributed to the absence of important manufacturing defects, to the fine microstructure with an important amount of austenite produced by SLM, and to a small amount of non-metallic inclusions precipitated as a result of the fast cooling and the high speed of solidification associated with the SLM process.Ministerio de Ciencia, Innovación y Universidades (grant RTI2018-097990-B-I00)Junta de Castilla y León (VA275P18) y (VA044G19)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

    Remediation of wastewaters containing tetrahydrofuran. Study of the electrochemical mineralization on BDD electrodes

    Get PDF
    This work contributes to the development of electro-oxidation on commercial boron doped diamond (BDD) anodes as an efficient and versatile environmental technology to deal with remediation of tetrahydrofuran (THF) polluted industrial wastewaters. Working with an undivided flow-by electrochemical cell, a systematic experimental study has been carried out to analyze the influence of the following operation variables: (i) initial THF concentrations in the range 500–1100 mg/L, (ii) supporting electrolyte, Na2SO4 and NaCl and (iii) current density in the range 300–1200 A/m2. The performance of the oxidation process was assessed through the change in the concentration of THF, Chemical Oxygen Demand (COD), and Total Organic Carbon (TOC) being the current density the variable that exerted the most positive kinetic influence; more precisely the reduction of COD after 60 min changed from 40% at japp = 300 A/m2 to 95.5% at japp = 1200 A/m2, whereas the reductions of TOC were typically higher than 95% for a value of the specific charge of Q = 10 A/h L. Besides, THF oxidation products have been analyzed, and the reactions’ pathway are proposed. Finally, the formation of chloride by-products, such as perchlorate was assessed observing that it was hindered at low current densities. In the view of these findings, it is concluded that THF oxidation on BDD anodes should be better performed at low current densities, i.e. 300 A/m2 for the type of wastewaters analyzed in the present work, to reach a compromise between effective degradation and the formation of undesirable chlorinated by-products.Financial support of Project ENE2010-15585 is gratefully acknowledged

    Microglial angiotensin type 2 receptors mediate sex-specific expression of inflammatory cytokines independently of circulating estrogen

    Get PDF
    Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia, Grant/Award Numbers: XUGA, ED431C 2018/10, ED431G/05; Instituto de Salud Carlos III, Grant/Award Numbers: PI20/00385, RD16/0011/0016, CIBERNED; Secretaría de Estado de Investigación, Desarrollo e Innovación, Grant/Award Number: RTI2018-098830-B-I00; Regional European Development Fund (FEDER)There are sex differences in microglia, which can maintain sex-related gene expression and functional differences in the absence of circulating sex steroids. The angiotensin type 2 (AT2) receptors mediate anti-inflammatory actions in different tissues, including brain. In mice, we performed RT-PCR analysis of microglia isolated from adult brains and RNA scope in situ hybridization from males, females, ovariectomized females, orchiectomized males and brain masculinized females. We also compared wild type and AT2 knockout mice. The expression of AT2 receptors in microglial cells showed sex differences with much higher AT2 mRNA expression in females than in males, and this was not dependent on circulating gonadal hormones, as observed using ovariectomized females, brain masculinized females and orchiectomized males. These results suggest genomic reasons, possibly related to sex chromosome complement, for sex differences in AT2 expression in microglia, as the AT2 receptor gene is located in the X chromosome. Furthermore, sex differences in expression of AT2 receptors were associated to sex differences in microglial expression of key anti-inflammatory cytokines such as interleukin-10 and pro-inflammatory cytokines such as interleukin-1β and interleukin-6. In conclusion, sex differences in microglial AT2 receptor expression appear as a major factor contributing to sex differences in the neuroinflammatory responses beyond the effects of circulating steroidsThere are sex differences in microglia, which can maintain sex-related gene expression and functional differences in the absence of circulating sex steroids. The angiotensin type 2 (AT2) receptors mediate anti-inflammatory actions in different tissues, including brain. In mice, we performed RT-PCR analysis of microglia isolated from adult brains and RNA scope in situ hybridization from males, females, ovariectomized females, orchiectomized males and brain masculinized females. We also compared wild type and AT2 knockout mice. The expression of AT2 receptors in microglial cells showed sex differences with much higher AT2 mRNA expression in females than in males, and this was not dependent on circulating gonadal hormones, as observed using ovariectomized females, brain masculinized females and orchiectomized males. These results suggest genomic reasons, possibly related to sex chromosome complement, for sex differences in AT2 expression in microglia, as the AT2 receptor gene is located in the X chromosome. Furthermore, sex differences in expression of AT2 receptors were associated to sex differences in microglial expression of key anti-inflammatory cytokines such as interleukin-10 and pro-inflammatory cytokines such as interleukin-1β and interleukin-6. In conclusion, sex differences in microglial AT2 receptor expression appear as a major factor contributing to sex differences in the neuroinflammatory responses beyond the effects of circulating steroidsS

    Participatory audiences in the European public service media: Content production and copyright

    Get PDF
    The interactivity and participation of the public in the media is not a novelty, but has increased significantly with the adaptation to the digital convergence process. The possibility for audiences to share content through social platforms or generating its own is raising new ethical and legal issues. In this context, the public service audiovisual media must be pioneer both in the introduction of new participatory experiences and in the debate on the behaviour of the media regarding the interaction with its users. The objective of this article is twofold: on the one hand, to approach the current scenario of participatory mechanisms present in the European public service audiovisual media; on the other hand, to determine how this media is solving the new problems generated by the increase in user interaction. The research on participatory mechanisms offered by public service media shows that social networks, blogs, and comment sections are the main tools for discursive participation, while the field of creative participation requires the exploitation of new innovation strategies. The main challenge arising from this situation is how to control the legality of user-generated content and how to manage the ownership of copyright according to social values represented in public service media

    Dietary Strategies for Metabolic Syndrome: A Comprehensive Review

    Get PDF
    Metabolic syndrome is a cluster of metabolic risk factors, characterized by abdominal obesity, dyslipidemia, low levels of high-density lipoprotein cholesterol (HDL-c), hypertension, and insulin resistance. Lifestyle modifications, especially dietary habits, are the main therapeutic strategy for the treatment and management of metabolic syndrome, but the most effective dietary pattern for its management has not been established. Specific dietary modifications, such as improving the quality of the foods or changing macronutrient distribution, showed beneficial effects on metabolic syndrome conditions and individual parameters. On comparing low-fat and restricted diets, the scientific evidence supports the use of the Mediterranean Dietary Approaches to Stop Hypertension (DASH) diet intervention as the new paradigm for metabolic syndrome prevention and treatment. The nutritional distribution and quality of these healthy diets allows health professionals to provide easy-to-follow dietary advice without the need for restricted diets. Nonetheless, energy-restricted dietary patterns and improvements in physical activity are crucial to improve the metabolic disturbances observed in metabolic syndrome patients

    Peritoneal protein transport during the baseline peritoneal equilibration test is an accurate predictor of the outcome of peritoneal dialysis patients

    Get PDF
    [Abstract] Background: Peritoneal protein excretion (PPE) is a potential marker of the outcome in peritoneal dialysis (PD) patients. Method: Observational study of a cohort of 269 patients starting PD in a single unit. Study variables: total PPE during a baseline peritoneal equilibration test (PET; PET-PPE) and 24-hour PPE. Control variables: essential baseline demographic, laboratory and adequacy markers. Main outcomes: mortality, cardiovascular events and risk of peritonitis. We applied univariate and multivariate strategies of survival analysis. Main Results: PET-PPE sustained a significant, yet limited correlation with 24-hour PPE (r = 0.46, p < 0.0005). At baseline, the main study variables showed an independent correlation with peritoneal transport characteristics (D/P240’ creatinine) and cardiovascular comorbidity. PET-PPE (p < 0.0005, model global χ2 59.4) was a more accurate predictor of overall mortality than 24-hour PPE (p = 0.04, χ2 50.5). Moreover, PPE during PET, but not 24-hour PPE, was an independent predictor of the risks of cardiovascular and infectious mortality, and of peritonitis. Conclusions: Baseline PPE represents a strong independent marker of survival of PD patients. Estimation of PPE during PET is more accurate than 24-hour PPE for this purpose, sustains a definite independent association with cardiovascular and infectious mortality, and shows a significant correlation with the risk of peritonitis
    corecore