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Healthcare challenges for people with diabetes during the national state of emergency due to covid-19 in lima, peru: Primary healthcare recommendations
No full textPatients diagnosed with type 2 diabetes mellitus, who then become infected with SARS-CoV-2, are at greater risk of developing complications from COVID-19, which may even lead to death. Diabetes is a chronic condition that requires continuous contact with healthcare facilities; therefore, this type of patients should have regular access to medicines, tests and appointments with healthcare personnel. In Peru, care and treatment continuity have been affected since the national state of emergency due to COVID-19 began; because many healthcare facilities suspended outpatient consultations. The strategies presented in this study were developed by different Peruvian health providers in the pandemic context to ensure care continuity for people with diabetes. This article provides recommendations to strengthen primary healthcare, because it is the first level of healthcare contact for patients with diabetes.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Experimental and analytical bond behaviour of masonry strengthened with steel reinforced grout (SRG)
No full textSteel Reinforced Grout (SRG) is gaining popularity as a retrofitting system for structural elements due to advantages such as its effectiveness and ease of installation. The good performance of SRG system has turned out to be substantially dependent on the behaviour of the bond between the composite layer and the substrate. This paper presents an experimental study of the bond behaviour of Peruvian masonry strengthened with SRG, along with a characterization of the materials by means of direct tensile tests on the fiber and compression tests on the mortar. The criteria of the sample's geometry, construction and test procedure are discussed for each trial since up to now there has been a gap in the standards that control them. In addition, an analytical model is employed in order to obtain design bond parameters to define a Cohesive Material Law (CML). The strain profile, slip profile, force profile and shear stress profile along the length of the bond are presented for each bond test. Finally, an optimal bond length is proposed for SRG material and a fracture energy value at the matrix-fiber interface.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
A low-cost measurement device for recording perceptions of thermal comfort
No full textIn this article, we describe the implementation of a low-cost device that registers perceptions of thermal comfort. The parameters of relative humidity (RH), temperature, thermal sensation (cold, cool, neutral, warn, hot) and clothing worn by people are collected. The design and validation of the device in an indoor environment are explained, and the calibration curves of the temperature and relative humidity sensors are obtained. The measurement results for the device from 10 people are shown. The study was carried out in the village of Imata (high Andean zone), at 4700 masl in the south of Peru. © Published under licence by IOP Publishing Ltd.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
A regularized quantitative ultrasound method for simultaneous calculation of backscatter and attenuation coefficients
No full textQuantitative ultrasound has shown potential of improving medical diagnosis. In this work, a regularized power law (RPL) for the joint estimation of backscatter coefficient (BSC) and attenuation coefficient (AC) parameters was derived and tested with simulated phantoms and in vivo. For the RPL method, a total variation regularization term regarding the BSC and AC parameters were used. The results were compared with ground truth simulated values. An improvement of precision can be appreciated without compromising the accuracy by factor of 80% and 54% according to bias and coefficient of variation, respectively. The in vivo experiments showed comparable results of the algorithm with the literature (i.e. fibroadenoma:1.90 ± 0.31dB.cm-1.MHz-1, normal tissue: 0.62 ± 0.20dB.cm-1.MHz-1). The results suggest the RPL method has the potential to accurately and precisely estimating BSCs and ACs. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Creep of geopolymeric concrete obtained from mining tailings
No full textGeopolymeric materials have recently been considered a revolutionary class of materials, due to the diversity of applications where they can be used, this derived from their good mechanical resistance, thermochemical stability and good fire resistance. From 1970 to the present, a notable increase has been observed in the number of scientific publications dealing with the synthesis and applications of geopolymeric materials with industrial application. Several publications have reported geopolymers as alternative materials to Portland cement, which will allow having a green construction industry in the coming years. The elaboration of geopolymeric materials is relatively simple, beginning with the identification of a source rich in amorphous aluminosilicates and a hardening compound (mainly alkaline in nature) which are properly mixed until a homogeneous and workable paste is obtained, then can harden at room temperature and acquire good mechanical resistance in a few hours. On the other hand, mining in Peru is one of the most important industries due to its contribution to the economic development of the country. However, mining is also one of the industries with the greatest negative impact on the environment, mainly due to the enormous amount of inorganic waste that it generates and which is currently accumulated without any prospect of recycling or reuse. Therefore, this research was conducted to elaborate concretes from mining tailings and to evaluate their mechanical behavior in creep (between 500 and 600 ºC). The results obtained allow us to propose the use of mining tailings for the elaboration of geopolymeric thermal barriers that work in conditions of intermediate temperatures, up to 600 ºC. © 2020, Avestia Publishing. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Coffee pulp: An industrial by-product with uses in agriculture, nutrition and biotechnology
No full textThe coffee shell or pulp is the first by-product obtained from the processing of coffee. It represents approximately 40 to 50% of the coffee berry’s weight. Currently, in much of the industry, it is a waste product with a major environmental impact on the water and soil, flora and fauna, and a problem to nearby populations in terms of odor and proliferation of insects and pathogenic microorganisms. This is a review that compiles alternative uses of coffee pulp in agriculture, food and nutrition, medicine and biotechnology. In food and agriculture, for example, the pulp can be used as organic fertilizer to improve degraded soils, in the biological control of plant pathogens, as food or substrate for microorganisms and worms, as feed for chickens, sheep, goats, fish and other animals, and in the productions of foods and beverages for human consumption. In biotechnology, coffee pulp can be used in the cultivation of edible fungi, production of enzymes, substrate for caffeine degrading microorganisms and for microorganisms that produce natural fungicides. Although many of these applications have been proposed and studied, there are also several novel uses that are in the early stages of development; for example, the use of pulp bioactive compounds to make food supplements, or to increase dietary fiber contents in foods and beverages, as well as for the production of biocontainers and biopackaging, alternatives to plastics and their serious environmental impact. © 2020 Reviews in Agricultural Science.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Modeling of the nominal power of a PV generator under clear and cloudy sky conditions
No full textThe characterization of the nominal power under real operating conditions is crucial for the correct evaluation of a photovoltaic generator. Several earlier studies proposed different methods based on empirical models for the estimation of the nominal power. These methods require experimental data obtained during optimal days under clear sky conditions and are not suitable for days deviating from these optimal conditions and, thus, generating a significant amount of noise in the data. In this sense, we propose a non-parametric statistical approach to filter out this noise to reliably estimate the real nominal power in the latter conditions. The period of study was 107 days. These were divided in two categories, clear and partly cloudy sky conditions. The results show that our statistical method allows to obtain the same nominal power under partly cloudy conditions as under clear sky. This was possible by applying a kernel density estimation to filter the outliers and the noise under cloudy conditions. © 2019. The Authors. Published by International Solar Energy Society Selection and/or peer review under responsibility of Scientific CommitteeConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Exploring the inuence of the emotional state on the efficiency for correcting defects in conceptual models: A live study
Get PDFThe purpose of this live study is to investigate the impact of emotional states on the efficiency of correcting defects within a Conceptual Model verification context. We plan to use the CoSTest tool for verifying defects and measure the experimented emotions during the testing tasks through I-PANAS-SF and SUDS instruments. Furthermore, the design, overview and potential threats of this experiment are presented.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Carbon and nutrient accumulation in mangrove sediments affected by multiple environmental changes
No full textPurpose In order to assess the impact of anthropogenic activities on carbon and nutrient accumulation, total organic carbon (TOC), nitrogen (TN), and phosphorus (TP) accumulation rates were examined in a Pb-210-dated mangrove sediment core from Sepetiba Bay, Brazil, a coastal region impacted by multiple environmental changes during the previous century. Materials and methods A 50-cm length sediment core was collected from a mangrove forest in Sepetiba Bay. Sediment subsamples were analyzed to measure TOC, TN, delta C-13, and delta N-15 using an elemental analyzer attached to an isotope ratio mass spectrometer Thermo Finnigan Model Delta Plus XP, whereas colorimetric analysis were used to measure TP. For (210)Pbex analyses, gamma-ray measurements were performed in a semiplanar intrinsic germanium high purity coaxial detector, coupled to a multichannel analyzer, whereas the sediment accumulation rate (SAR) was calculated according to the constant initial concentration (CIC) method. Also, carbon and nutrient fluxes were calculated using SAR and TOC, TN, and TP contents, whereas statistical differences were evaluated by ANOVA + Tukey HSD analysis with previous data normalization. Results and discussion The calculated sedimentation rate (similar to 8.1 mm year(-1)) since the early 1900s was up to threefold higher than the global mean determined for mangrove forests (similar to 2.8 mm year(-1)) and the regional sea level rise (similar to 3.2 mm year(-1)). Significantly higher TOC, TN, and TP fluxes, up to nearly 1000, 90, and 15 g m(-2) year(-1), respectively, were observed after the water diversion from a nearby drainage basin in the 1950s and an increase in sewage effluent input, which increased in the early 1990s. After this period, lighter delta C-13 values (similar to - 25 parts per thousand) indicate an increased importance of the terrestrial organic matter source, while lower TOC:TN ratios (similar to 11) and heavier delta N-15 values (similar to + 9 parts per thousand) suggest an increased influence of anthropogenic fertilization on inorganic nitrogen accumulation. Conclusions The significantly higher accumulation rates during the last decades evidenced the role of mangrove sediments as sinks for anthropogenically enhanced inputs of carbon and nutrients. Also, studies on carbon and nutrient accumulation evidenced the need for further research in eutrophic coastal areas.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
One-step synthesis of polyethyleneimine-coated magnetite nanoparticles and their structural, magnetic and power absorption study
No full textMagnetic nanoparticles (NPs) are especially interesting for several biomedical applications due to their chemical surface, especially for targeted cancer imaging and therapeutics. In order to realize these applications, it is important to know their magnetic properties among other complementary properties that help to improve the understanding of the synthesis process. In this work, we report the magnetic properties of polyethyleneimine-coated magnetite (PEI-Fe3O4) NPs synthesized by a one-step method via the co-precipitation method and using PEI as a stabilizer. Transmission electron microscopy (TEM) images revealed agglomerated magnetic nanoparticles with an average size of similar to 10 nm; meanwhile, the X-ray diffraction (DRX) analysis confirmed a pure magnetite phase. The study of magnetic properties shows a superparamagnetic system with coexistence of non-interacting single NPs with a low blocking temperature (similar to 35 K) and interacting NPs in the aggregates with a higher blocking temperature (>150 K), in which the interparticle interactions of magnetic cores dominate over surface spin disorder. The interaction between the surface spin-disorder layer and NP core was found to be weak, related to a weak exchange bias effect. A maximum specific loss power (SLP) value of 70 W g(-1) was obtained (f = 571 kHz and H = 23.87 kA m(-1)) indicating that the magnetic response plays a crucial role in determining the heating efficiency for future applications.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte