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Design of a "test Cell" to be located at 4500 masl in a high Andean region of Peru and dynamic simulation of the thermal performance of housing wall materials
No full textThe objective of the present study is to select appropriate wall materials for houses in high Andean regions based on the measurements of the thermal behavior of construction materials using a "Test Cell" under real environmental conditions. It will be the first "Test Cell" to be installed in Peru, in Imata-Arequipa, at 4500 masl. The design and thermal analysis of the "Test Cell" are presented using dynamic simulations with the EnergyPlus program. Initially, the thermal performance of adobe, a traditional construction material in rural regions of Peru, is simulated using real meteorological data recorded in Imata between August 18 and 24, 2018, a period with low temperatures (-12.6 °C). © Published under licence by IOP Publishing Ltd.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Occurrences of extreme solar irradiance at 3812 meters above sea level, at Lake Titicaca (Puno - Peru) [Ocurrencias de Irradiancia Solar Extrema a 3812 m.s.n.m., a nivel del Lago Titicaca (Puno - Perú)]
No full textThe capture of the solar resource by means of photovoltaic systems to transform it into electricity depends on the solar irradiance during the day and climatic factors, the latter being of great importance. Aiming at evaluating and determining the occurrences of extreme solar irradiance and the Peak Sun Hours (HSP) in varied climatic conditions of the altiplano at 3812 meters above sea level, at the level of Lake Titicaca (Puno - Peru) and its effects on the photovoltaic system. The solar irradiance measurement was performed with two short-circuit photovoltaic modules each, where the Isc short-circuit current was connected to a current transducer to convert it into an analog electrical signal processed and stored every second in a programmable Logic Controller High precision (PLC). The results show the occurrence of extreme solar irradiance exceeding 1000 W / m2 and the solar constant for a few seconds on partially cloudy days, determining that the HSP is above 6 kWh / m2 / d and its effects on the photovoltaic system. Finally, in the Puno Altiplano, over irradiance is caused by the interaction of the clouds around the sun and the transitory presence of rain in short periods of time that affects the electrical protection system of a photovoltaic system. © 2020 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Physico-chemical characterization, metabolomic profile and in vitro antioxidant, antihypertensive, antiobesity and antidiabetic properties of Andean elderberry (Sambucus nigra subsp. peruviana)
No full textBACKGROUND: The consumption of fruits, mainly berries, has been associated with beneficial health properties. These properties would be related to the quantity and quality of the metabolites present. Some native berries from the Andes, such as Andean elderberry, would be an important source of metabolites with bioactive properties. OBJECTIVES: To evaluate at the physico-chemical and metabolomic level the characteristics of the elderberry from four different high Andean regions, and to determine their bioactive potential through in vitro tests. RESULTS: Significant differences were found in the evaluated characteristics according to the Region of procedence of the fruit. Glucose was the main sugar for all berry samples, followed by fructose. Among the most important organic acids, citric and malic acid were found. Elderberry from Apurimac presented the highest content of total sugars and lower content of total acids in comparison to the samples from other procedences. UPLC-PDA results indicate that Junin elderberries presented the highest value of total phenolic compounds with high contents of flavonols, hydroxycinnamic acids and anthocyanins. Andean elderberry presented cyanidin 3-O-glucoside and cyanidin 3-O-sambubioside as main anthocyanins as well as their respective isomers. All samples showed inhibition activities against the different evaluated enzymes. Elderberries from Apurimac and Junin, displayed the lowest values of IC50 for the inhibition of -amylase and -glucosidase, while for the inhibition of lipase and angiotensin converting enzyme (ACE-I) elderberries from Junin displayed the lowest IC50 values. CONCLUSIONS: The results of this study suggest that Andean elderberry could be considered as an important source of bioactive compounds with properties that could be highlighted by the nutraceutical and functional food industries. © 2020 - IOS Press and the authors. All rights reserved.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Diurnal cycle of raindrops size distribution in a valley of the peruvian central Andes
No full textIn the Central Andes of Peru, convective and stratiform rainfall occurs, frequently associated with convective storms. The raindrop size distributions (RSD), measured by a Parsivel-2 optical disdrometer, were characterized by the variation of their normalized parameters. The RSD dataset includes measurements corresponding to 18 months between 2017 and 2019. As a result, it was found that the mass-weighted mean diameter Dm and the Nw parameter present respectively high and low values, in the interval of 15-20 LST (local standard time), wherein deeper and more active clouds appear. The events including convective rainfall contribute 67.5% of the accumulated total, wherein 92% corresponds to the 15-20 LST interval. It is concluded that the spectral variability of the RSD is strongly controlled by the cloudiness configuration field developing over the west (convection over highlands) and east (convection over Amazon) sides of the valley. In the afternoon, clouds develop and drift to the east, over the Andean valleys and towards the Amazon, intensified by local orographic circulation. The opposite happens at night, when the stratiform rainfall is dominant and it is controlled by clouds, located in the Inter-Andean valley, generated by the convection fields formed over the Amazon forest. © 2019 by the authors.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Solid surface composite materials manufactured from syrup of polymethyl methacrylate, alumina trihydrate and natural mineral fillers
No full textA composite material, which properties are similar to the commercial material Krion®, was manufactured using polymethyl methacrylate (PMMA) syrup, alumina trihydrate (ATH) and natural mineral fillers (CMN). For this purpose, composites have been manufactured in 2 stages: In first stage, free radical polymerization of methyl methacrylate (MMA) was carried out to obtain syrup of polymethyl methacrylate. Polymerization parameters were determined in order to avoid autoacceleration effect and to get syrup which PMMA conversion avoids precipitation of ATH particles. In second stage, composite samples were manufactured using the obtained syrup, ATH and CMN particles and, then, they were tested in order to determine suitable parameters to get similar properties to Krion®. It has been proved that syrup must have a MMA to PMMA conversion between 20% and 25% to avoid autoacceleration effect and precipitation of ATH particles. To obtain such syrup, polymerization must be carried out using 0,1% of benzoyl peroxide (PBO) y 0,2% of ethylene glycol dimercaptoacetate (EGDM) at 85°C during 90 minutes. Similarly, to get composites which properties are similar to Krion®, the manufacturing parameters of a PMMA composite reinforced with ATH and CMN particles are: 40% syrup / 60% ATH / %CMN variable according to the type of filler, 0,1% of additional PBO, 2,0% ethylene glycol dimethacrylate (EGDMA) y curing time 13 hours inside a furnace at 85°C. Properties of the composite that has been manufactured under these conditions and only contains ATH filler are: flexural resistance of 53 MPa, flexural elastic modulus of 8054 MPa and hardness of 91 HRM. Esthetic quality improves with the incorporation of CMN but mechanical properties decrease. © 2020, Universidade Federal do Rio de Janeiro. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Taxonomic status of parapraocis, a new genus of praociini (Coleoptera: Tenebrionidae: Pimeliinae) from Peru [Estatus taxonómico de parapraocis, un nuevo género de praociini (Coleoptera: tenebrionidae: pimeliinae) de Perú]
No full textThe new genus Parapraocis (Pimeliinae: Praociini) is described to accommodate three species from the northern Peruvian coast previously placed in the genus Praocis Eschscholtz: Parapraocis vagecostata (Fairmaire, 1902) n. comb. (type species), Parapraocis rossi (Kulzer, 1958) n. comb., and Parapraocis fumaria (Kulzer, 1966) n. comb. Diagnosis, description and illustrations of external morphology, male and female genitalia, and habitus photographs for two of its species are presented. A discussion on the raising of this new genus as well as homological structures in the female genitalia of the Praociini are also included. © Flores, G.E. & Giraldo A.E.-.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Bioprospection of native psychrotolerant plant-growth-promoting rhizobacteria from peruvian andean plateau soils associated with chenopodium quinoa
No full textThe Peruvian Andean Plateau, one of the main production areas of native varieties of Chenopodium quinoa, is exposed to abrupt decreases in environmental temperature, affecting crop production. Plant-growth-promoting rhizobacteria that tolerate low temperatures could be used as organic biofertilizers in this region. We aimed to bioprospect the native psychrotolerant bacteria of the quinoa rhizosphere in this region that show plant-growth-promoting traits. Fifty-one strains belonging to the quinoa rhizosphere were characterised; 73% of the total could grow at low temperatures (4, 6, and 15 °C), whose genetic diversity based on DNA amplification of interspersed repetitive elements (BOX) showed 12 different profiles. According to the 16S rRNA sequence, bacterial species belonging to the classes Beta-and Gammaproteobacteria were identified. Only three (6%) isolates identified as nonpathogenic bacteria exhibited plant-growth-promoting activities, like IAA production, phosphate solubilization, growth in a nitrogen-free medium, and ACC deaminase production at 6 and 15 °C. ILQ215 (Pseudomonas silesiensis) and JUQ307 (Pseudomonas plecoglossicida) strains showed significantly positive plant growth effects in aerial length (about 50%), radicular length (112% and 79%, respectively), and aerial and radicular mass (above 170% and 210%, respectively) of quinoa plants compared with the control without bacteria. These results indicate the potential of both psychrotolerant strains to be used as potential organic biofertilizers for quinoa in this region. © 2020, Canadian Science Publishing. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Lehmann-Suwa Residues Of Codimension One Holomorphic Foliations And Applications
No full textLet F be a singular codimension one holomorphic foliation on a compact complex manifold X of dimension at least three such that its singular set has codimension at least two. In this paper, we determine Lehmann-Suwa residues of F as multiples of complex numbers by integration currents along irreducible complex subvarieties of X. We then prove a formula that determines the Baum-Bott residue of simple almost Liouvillian foliations of codimension one, in terms of Lehmann- Suwa residues, generalizing a result of Marco Brunella. As an application, we give sufficient conditions for the existence of dicritical singularities of a singular real-analytic Levi-flat hypersurface M ⊂ X tangent to F. © 2020 International PressFondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Multifunctional in vitro bioactive properties: Antioxidant, antidiabetic, and antihypertensive of protein hydrolyzates from tarwi (Lupinus mutabilis Sweet) obtained by enzymatic biotransformation
No full textBackground and objectives: Tarwi is a legume that grows in the Andean region of Peru. This grain is characterized by having a high protein content (similar to 42%). In order to generate added-value products from this resource, the possibility of obtaining tarwi protein hydrolyzates (TPH) with in vitro bioactive properties was evaluated using Alcalase, Neutrase, and Flavourzyme enzymes, acting alone or in combination for up to 240 min. The in vitro evaluated properties were as follows: antioxidant (ABTS assay), antidiabetic (alpha-amylase, alpha-glucosidase and dipeptidyl peptidase IV (DPP-IV) inhibition), and antihypertensive (angiotensin-converting enzyme-I (ACE) inhibition). Findings: The TPH obtained from the different enzyme treatments exhibited important antioxidant, antidiabetic (specially for DPP-IV inhibition), and antihypertensive properties. One-stage treatment using Alcalase for 240 min and two sequential stage treatments with Alcalase-Neutrase for 180 min presented the highest ABTS antioxidant activity and lowest IC50 values for DPP-IV and ACE corresponding to 2.0-1.95 mu mol TE/mg, 2.14-2.61 and 0.16-0.11 mg/ml, respectively. Conclusions: The results of this research demonstrate that TPH exhibit in vitro multifunctional bioactive properties. Significance and novelty: TPH could potentially be used in the prevention or management of chronic diseases related to the development of oxidative processes, diabetes, and hypertension.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Depression in women with a diagnosis of breast cancer. Prevalence of symptoms of depression in Peruvian women with early breast cancer and related sociodemographic factors
No full textWe sought to review literature on the prevalence of symptoms of depression in women with a diagnosis of breast cancer (BC) and in the Peruvian population determine the prevalence of symptoms of depression and to describe the association with sociodemographic characteristics. Descriptive cross-sectional analytical study of 254 patients from the National Cancer Institute of Peru (Instituto Nacional de Enfermedades Neoplasicas) with a diagnosis of clinical stage I or II BC. The patients included women aged between 26 and 67 years old. Symptoms of depression were monitored by the Beck Depression Inventory-II. Moreover, clinical features and patient sociodemographic characteristics were analyzed and their association with depression was assessed by logistic regression. The average age of the patients was 47.8 +/- 9.2 years; 5.4% of the patients were postmenopausal at the time of the questionnaire. About 55% of women were from Lima, 58.3% had completed secondary education (11 +/- 3.2 years), 45.7% were not working, and 46.5% were single. The prevalence of depression was 25.6% at the time of BC diagnosis. Of those patients with symptoms of depression, 16.9% showed symptoms of mild depression, 6.3% moderate, and 2.4% severe. A multivariable logistic regression model showed that in Peruvian women with a diagnosis of BC being married or employed significantly decreased the odds of presenting depressive symptoms (P=0.029 and 0.017, respectively). Our main limitation was the lack of evaluation of depressive symptoms before the diagnosis, during or at the end of treatment. Another limitation was that the Beck Depression Inventory-II test could only identify depressive symptoms, but not depression as a disease. We have reviewed relevant literature on depression in women with a diagnosis of BC. The data presented suggests an association between both employment and marital status with depressive symptoms among Peruvian women with a diagnosis of BC. Pre-emptive support for women at risk could influence resilience and/or motivation for compliance with antineoplastic treatments. (C) 2020 Elsevier Inc. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte