New COVID-19 ventilation guidelines have resulted in higher energy consumption to maintain indoor air quality (IAQ), and energy efficiency has become a secondary concern. Despite the significance of ...the studies conducted on COVID-19 ventilation requirements, a comprehensive investigation of the associated energy challenges has not been discussed. This study aims to present a critical systematic review of the Coronavirus viral spreading risk mitigation through ventilation systems (VS) and its relation to energy use. COVID-19 heating, ventilation and air conditioning (HVAC)-related countermeasures proposed by industry professionals have been reviewed and their influence on operating VS and energy consumption have also been discussed. A critical review analysis was then conducted on publications from 2020 to 2022. Four research questions (RQs) have been selected for this review concerning i) maturity of the existing literature, ii) building types and occupancy profile, iii) ventilation types and effective control strategies and iv) challenges and related causes. The results reveal that employing HVAC auxiliary equipment is mostly effective and increased fresh air supply is the most significant challenge associated with increased energy consumption due to maintaining IAQ. Future studies should focus on novel approaches toward solving the apparently conflicting objectives of minimizing energy consumption and maximizing IAQ. Also, effective ventilation control strategies should be assessed in various buildings with different occupancy densities. The implications of this study can be useful for future development of this topic not only to enhance the energy efficiency of the VS but also to enable more resiliency and health in buildings.
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•A PRISMA-based systematic review of the COVID-19 ventilation energy challenges.•The Ventilation energy use rose after the pandemic; this alarms energy conservation.•The topic is developed by evaluation-type studies focusing on educational buildings.•Increased fresh air supply is the most significant challenge during the pandemic.•Efficiency improvement and optimization of auxiliary equipment were mainly effective.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Induction motor are electrical machines used in a wide variety of industrial applications. However, due to their applications, are subjected to undesirable operating conditions. A complementary ...technique that aids in fault diagnosis in induction motors is infrared thermography. This paper proposes a methodology based on automatic learning and unsegmented infrared imaging for classifies and diagnosis failures on induction motor and their kinematic chain. The proposed methodology is analyzing the unsegmented infrared thermography, taking directly from the thermogram significant statistical features that describe the thermal behavior of the electromechanical system, to later reduce the set of characteristics and, through a machine learning algorithm, classify the fault condition. To demonstrate the efficiency of the proposed methodology, this paper presents the health condition analysis and three fault conditions in an induction motor: a broken rotor bar, bearing damage, and misalignment.
Desde el 70 al 80 Aniversario de la fundación del Instituto de Medicina Tropical "Pedro Kourí", los investigadores, profesionales y técnicos de este centro, han laborado en cooperación con diversas ...instituciones académicas y de los servicios de salud de Cuba (en equipos multidisciplinarios) en las tareas de desarrollo científico, innovación tecnológica y construcción de capacidades. Este artículo resume las principales investigaciones realizadas sobre la tuberculosis desde 2008-2017; como contribuciones al Programa Nacional de Control y Eliminación de la Tuberculosis con la perspectiva de aumentar la calidad, efectividad y eficiencia de las acciones y acelerar la solución de la incidencia y la mortalidad por tuberculosis, para la investigación, la vigilancia y control de la tuberculosis. Se presentan evidencias que fundamentan las innovaciones en el manejo clínico terapéutico de pacientes inmunocompetentes e inmunocomprometidos, en niños y adolescentes, sobre las indicaciones para el control de la infección tuberculosa latente, la vigilancia de los desenlaces del tratamiento anti-tuberculosis, la investigación de contactos de casos, los cambios en el sistema de registro e información, el monitoreo y evaluación de la calidad de la detección de casos de tuberculosis, el impacto sobre la morbilidad y la mortalidad.
Husk tomato (Physalis ixocarpa Brot. var. Rendidora) waste was evaluated as a source of specialized pectin, and pectin extracted from this waste was characterized physicochemically. Fruit was ...blanched for 10 or 15 min and extracted in 0.1 N HCl for 15 to 25 min. Extracted pectin was subjected to physicochemical analysis. For all extraction conditions, the percentage of anhydrogalacturonic acid exceeded 60%, indicating that husk tomato was a good source of pectin. The degree of esterification of pectin molecules was 63% to 91%. The amount of extracted pectin decreased with increasing extraction time. The apparent viscosity of husk tomato pectin showed the characteristic behavior of pseudoplastic fluids. Neutral sugars were identified, and the amounts of 6 sugars (fucose, rhamnose, arabinose, galactose, glucose, and xylose) were quantified. Sugars identified in husk tomato pectin and present in the Rhamnogalacturonan I region, arabinose, galactose, and rhamnose suggest a highly branched structure, which will influence its future applications. Molecular weight values were 542 to 699 kDa, exceeding molecular weight values reported for commercial citrus pectins from 134 to 480 kDa. The extraction process significantly (P < 0.05) influenced the physicochemical properties of pectin. Up to 19.8% from the total amount of pectin in the husk tomato was extracted by 10 min of blanching and 20 min of a more heat treatment. Our findings indicate that husk tomato can be a good alternative source of pectin having highly distinctive physicochemical characteristics.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Computer vision plays an important role in problem solving, mainly in those problems which are focused on human monitoring, being the facial features the most important among them. In this paper, a ...methodology for detecting eyes and mouth via software is presented, using image processing techniques such as color space conversion, thresholding and erosion. It has the characteristic of being adaptable to any person and works in both day and night environments, taking advantage in the ability to detect which environment is. To obtain the image in a daytime environment, the image is captured with natural light, while for night using an infrared capture system becomes. The system was tested in a software application developed with satisfactory results.
Myricetin is a flavonol with high antioxidant properties. In this research, the fluorescence emission of myricetin powder and its solutions in different solvents were measured and analyzed by ...comparing with the results of calculations. Comparison of the calculated and measured characteristic wavelengths allowed the identification of all the spectral features in the fluorescence spectra of myricetin powder and solutions with different concentrations. The computation was based on modeling the process of the excited state intermolecular proton transfer, which predicts the formation of tautomeric forms of the flavonol molecule. Characteristic emission wavelengths were obtained using TDDFT/M06-2X/6-31++G(d,p). To understand the influence of the hydroxyl groups in the B-ring of the flavonol molecule on the emission spectrum, we also compared the fluorescence spectra of myricetin with those of kaempferol and quercetin. Moreover, based on the analysis of the changes in the shape of the FL spectra with the concentration of the solution, a criterion for the complete dissolution of the flavonol powders was established, which is important for bioavailability of flavonoids.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary
Radio frequency (RF) treatments have been reported for pasteurization and disinfestation of diverse grains such as corn. Yellow corn (Zea mays cv. Everta) is the kernel employed for popcorn, ...a popular snack in different countries. In this study, yellow corn was subjected to RF heating (until reach 52 °C), holding time (1 min) and cooling with forced air (until room temperature) as a disinfestation protocol. RF heating took around 6 min for batches of 10 kg and 3.5 min for batches of 20 kg. Even moisture and water activity of the grains were affected by the protocol (P < 0.05), and similar physical properties were obtained in 20‐kg RF‐treated batches. As an advantage, the popping ability of the grains was not affected by the RF heating in comparison with untreated samples (P > 0.05). Short RF heating may be considered as potential treatment for yellow corn, keeping kernel conditions for popcorn production.
Justification and experimental strategy for RF treatments.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Controversial findings regarding the association between pro-inflammatory cytokines and depression have been reported in pregnant subjects. Scarce data about anxiety and its relationships with ...cytokines are available in pregnant women. To understand the association between anxiety and cytokines during pregnancy, we conducted the present study in women with or without depression.
Women exhibiting severe depression (SD) and severe anxiety (SA) during the 3rd trimester of pregnancy (n = 139) and control subjects exhibiting neither depression nor anxiety (n = 40) were assessed through the Hamilton Depression Rating Scale (HDRS) and the Hamilton Anxiety Rating Scale (HARS). Serum cytokines were measured by a multiplex bead-based assay. Correlation tests were used to analyze the data and comparisons between groups were performed. A general linear model of analysis of variance was constructed using the group as a dependent variable, interleukin concentrations as independent variables, and HDRS/HARS scores and gestational weeks as covariables.
The highest levels of Th1- (IL-6, TNF-α, IL-2, IFN-γ), Th17- (IL-17A, IL-22), and Th2- (IL-9, IL-10, and IL-13) related cytokines were observed in women with SD + SA. The SA group showed higher concentrations of Th1- (IL-6, TNF-α, IL-2, IFN-γ) and Th2- (IL-4, and IL-10) related cytokines than the controls. Positive correlations were found between HDRS and IL-2, IL-6, and TNF-α in the SA group (p < 0.03), and between HDRS and Th1- (IL-2, IL-6, TNF-α), Th2- (IL-9, IL-10, IL-13) and Th17- (IL-17A) cytokines (p < 0.05) in the SD + SA group. After controlling the correlation analysis by gestational weeks, the correlations that remained significant were: HDRS and IL-2, IL-6, IL-9, and IL-17A in the SD + SA group (p < 0.03). HARS scores correlated with IL-17A in the SA group and with IL-17A, IL-17F, and IL-2 in the SD + SA group (p < 0.02). The linear model of analysis of variance showed that HDRS and HARS scores influenced cytokine concentrations; only IL-6 and TNF-α could be explained by the group.
We found that the cytokine profiles differ when comparing pregnant subjects exhibiting SA with comorbid SD against those showing only SA without depression.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Despite the growing scientific evidence, the electricity market models used in Chile do not consider the effects of climate change on hydroelectric energy production. Based on a statistical analysis ...of the historical hydro-energy inflow dataset and a revision of the scientific literature, we suggest a set of technical and statistical criteria to determine an alternative representation of the hydro-energy uncertainty in the Chilean electricity market. Based on these criteria, we then propose an alternative range of historical hydrological data, which is built by shedding the first 35 years of the historical dataset (out of 59 years) and using only a reduced subset of 24 years. Additionally, we propose to capture the potential impacts of even more prolonged droughts on the Chilean electricity system by repeating the last nine years of data at the end of the 24 year-long series. The resulting extended subset of 33 hydro-years is approximately 10% drier on average than the original dataset of 59 years. The proposed range of hydrological data captures some of the anticipated effects of climate change on Chilean hydro-uncertainty reported in the literature and also preserves most of the intra-annual and spatial diversity of the original data.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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