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Cultural adaptation and validation of SATAQ-4 “Sociocultural attitudes towards appearance questionnaire-4” for peruvian population
No full textIntroduction: Eating disorders (anorexia and bulimia) have been increasing worldwide and nationally. Prior to the development of this disorder, adolescents' present body dissatisfaction, whose study through the ¨Tripartite Influence Model¨ gives us three main pressures: Pressure from parents, media and peers. Factors that are studied through SATAQ-4. We conduct a study to validate the Peruvian version of SATAQ-4 "Sociocultural Attitudes Toward Appearance Questionnaire-4". Methods: A cross-sectional study was carried out in 2015. It was started by culturally adapting the test. Subsequently, validity was determined through the validity of the construct, and reliability through internal consistency assessment and intra-observer reliability (test-retest). Results: We obtained a culturally adapted instrument which presented a mean greater than 3 in the Delphi method, an intraclass correlation equal to 0.83 and an internal consistency (Cronbach alpha) of 0.90. The confirmatory factor analysis supported the original five-factor structure and the convergent validity analysis (r Pearson) when compared with BSQ a correlation of 0.70. Conclusions: The instrument adequately measures the construct for which it was created and can be applied in the Peruvian university environment. © 2020 Sociedad de Neurologia Psiquiatria y Neurocirugia. All rights reserved.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Revisiting neutrino and sneutrino dark matter in natural SUSY scenarios
No full textWe study natural supersymmetric scenarios with light right-handed neutrino superfields, and consider the possibility of having either a neutrino or a sneutrino as a dark matter candidate. For the former, we evaluate the possibility of having SUSY corrections on the ν4→ν γ decay rate, such that the NuStar bounds are relaxed. We find that corrections are too small. For sneutrino dark matter, we consider thermal and nonthermal production, taking into account freeze-out, freeze-in, and super-weakly interacting massive particles mechanisms. For the nonthermal case, we find that the νR can reproduce the observed relic density by adjusting the R-sneutrino mass and Yukawa couplings. For the thermal case, we find the need to extend the model in order to enhance sneutrino annihilations, which we exemplify in a model with an extended gauge symmetry. © 2020 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/" Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
The CuO/ZnO and CuO/ZnO/biochar materials for water treatment
No full textThe research of new materials and methods for water treatment is necessary. Two sets of materials were prepared. The one set is composed from CuO/ZnO oxides with variable content of CuO and the second set consists of its biochar impregnated counterparts. The structure and phase composition was determined using X-ray diffraction method and morphology of the materials was studied using scanning electron microscopy. The photodegradation activity and adsorption properties were tested on model pollutant - Methylene blue (MB) dye solution. The experimental kinetic of the data was analyzed using pseudo-first-order and pseudo-second-order kinetic models and the equilibrium data was evaluated using Langmuir, Freundlich and Dubinin-Radushkievic models. It was found that optimal material for photodegradation of MB is 1% CuO/ZnO oxide and for the adsorption of MB is the best material raw corn cob biochar. © Published under licence by IOP Publishing Ltd.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
A note on the zeros of approximations of the Ramanujan Ξ -function
No full textIn this paper we review the study of the distribution of the zeros of certain approximations for the Ramanujan Ξ -function given by Ki (Ramanujan J 17(1):123–143, 2008), and we provide new proofs of his results. Our approach is motivated by the ideas of Velásquez (J Anal Math 110:67–127, 2010) in the study of the zeros of certain sums of entire functions with some condition of stability related to the Hermite–Biehler theorem. © 2020, The Author(s).Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Thermomechanical evaluation of geopolymeric and conventional concretes
No full textGeopolymers are a class of inorganic synthetic materials that in recent years have received extensive interest of the scientific community, mainly due to the variety of applications in which they can be used. The synthesis of these materials is based on a chemical process called geopolymerization, which consists of the alkaline activation of amorphous alumina and silica oxides present in many natural raw materials and industrial solid waste. Therefore, the present work proposes the use of inorganic mining residues (mine tailings) from gold mining in the southern region of Peru, for the manufacture of geopolymeric concrete. The first part of the research focused on the physical, structural and microstructural characterization of the raw material (fine sand and mining tailings), then the volumetric matrix of mixtures for five types of geopolymer concrete was determined. Cylindrical samples of 20 mm diameter and 40 mm high geopolymeric concrete were manufactured, at the same time conventional Portland cement concrete was manufactured for comparison purposes. All materials were mechanically characterized by uniaxial compression tests at variable temperatures (from room temperature to 600 ºC), and they were also microstructurally characterized before and after mechanical tests. The main microstructural mechanisms responsible for the fracture and plastic deformation of geopolymeric and conventional Portland cement concretes have been determined. © 2020, Avestia Publishing. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Molecular diversity in pathogenic variants of Vibrio parahaemolyticus in Peru [Diversidad molecular de variantes patogénicas de Vibrio parahaemolyticus en el Perú]
No full textDuring the period from 1995 to 2017, in order to determine the diversity of Vibrio parahaemolyticus pathogenic variants in Peru, 102 Peruvian genomes (97 from a hospital setting and 5 from an out-of-hospital setting) were analyzed using the multilocus typification scheme and BLASTn in the search for virulence genes. Fifteen different sequence types were identified. It was found that the ST3 genotype, which is found in the pandemic clone, was the most abundant, with 52% (n=53); followed by ST120, with 23.5% (n=24); and the CC345 clonal complex, with 11.8% (n=12). A total of 89 analyzed strains presented genes encoding the pathogenicity island VpaI-7 (87.3%), while 96 presented the tdh gene (94.1%), and 6 the trh gene (5.9%). The ST3 genotype was the predominant one during the evaluated period, this genotype was the cause of a major outbreak in Peru’s past history. Other pathogenic genotypes found represent a latent public health risk associated with seafood consumption. © 2020, Instituto Nacional de Salud. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Performance evaluation and characterization of different photovoltaic technologies under the coastal, desertic climate conditions of Lima, Peru
No full textThis work presents the firsts results of the experimental characterization campaign under outdoor conditions carried out with three different photovoltaic (PV) module technologies: Standard poly-crystalline silicon (poly-Si) aluminum back surface field (Al-BSF) cells, mono-crystalline (c-Si) Heterojunction with Intrinsic Thin-Layer (HIT) cells, and amorphous and microcrystalline silicon (a-Si/µc-Si) thin-film tandem cells. We studied the behavior of these PV technologies and their performance in Lima's desertic and coastal climate during the period from May 2019 to July 2019. For this study, a new outdoor-PV laboratory was implemented at the Pontificia Universidad Católica del Perú (PUCP) with the help of the IDEA research group of the University of Jaén (UJA), Spain. The laboratory enables the characterization of PV modules by extracting the electrical parameters from the current-voltage (I-V) curve under outdoor conditions and by measuring the irradiance, the spectral distribution, the panel temperature, and the weather conditions. As a first step, the nominal maximum power of the PV modules under standard test conditions is obtained from the outdoor data. Then, an analysis of the different PV technologies' performance under the local climate conditions is presented by applying the Osterwald and the constant fill factor methods to compare the modeled and experimental maximum power. © 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
Recovery and characterization of Lucuma seed starch (Pouteria lucuma) with potential industrial application [Recuperación y caracterización del almidón de semilla de Lúcuma (Pouteria lucuma) con potencial aplicación industrial]
No full textToday starches have multiple industrial applications and have gained value as the raw material for the production of biodegradable packaging. Despite having been extracted from innumerable plant sources such as potatoes, corn, cassava, wheat, rice, quinoa, banana, etc,. The search for new low-cost sources continues to be important, seeking not to limit access to these traditional sources, which are the basis of alimentation in developing countries. For this reason, the objective of this research was to take advantage of the lucuma seed as a source for the isolation of starch, whose physicochemical and functional characterization would allow us to know its performance and its potential industrial application. For the isolation of the native starch, a sequence of physical operations using pilot equipment will be used, while the characterization tests included by physicochemical tests (% total starch, % humidity, % ash, water activity, % acidity, and pH) and functional properties: solubility index (ISA), swelling power (HP), water absorption capacity (CAA) and clarity of the paste. The results found that the total starch present in the lucuma seed is 83.97%. The functional properties show an ISA (15.55%), CAA (23.61 g of water / g of starch), HP (27.98 g of water / g of starch), and clarity of the paste of 18.67%, demonstrating the potential for possible uses in various industrial food processes. © 2020 Latin American and Caribbean Consortium of Engineering Institutions. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Within batch non-linear profile monitoring applied to shrimp farming: A case study
No full textThe operation of many batch processes involves critical characteristics that follow specific patterns over time. Sometimes the batch time is long enough that the operator can take corrective actions within it. This paper explores how to develop appropriate monitoring procedures for such situations within the context of a shrimp farming process. It uses a Gompetz non-linear model to describe the basic shrimp growth and defines the control limits through the prediction band around the estimated model. It proposes a method to generate a control chart soon enough within the batch so management can prioritize which ponds require the most attention. © 2021 Taylor & Francis Group, LLC.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Influence of wind shear uncertainty in long-term extreme responses of an offshore monopile wind turbine
No full textIn the field of stochastic dynamics of marine structures, the determination of long-term extreme responses is a crucial aspect to ensure the desired level of structural reliability. The calculation of these responses requires precise knowledge of the environmental conditions and reliable methods to predict the values associated with a reliability target level. While there is a very precise method to determine the value of these extreme values, e. g. the full long-term analysis (FLTA), this approach is computationally expensive. Then, approximated methods are needed.One practical approach for the determination of the most relevant environmental conditions for extreme calculation is the environmental contour method (ECM). However, some limitations have been detected when this method is used for offshore structures that consider survival strategies e. g. offshore wind turbines (OWT). Lastly, a modified ECM procedure (MECM) has been developed with the purpose to bypass the limitations of the traditional ECM. This method is based on short-term simulations and through an iterative process by testing many environmental contours in the operational range allows finding an important wind speed with its corresponding return period and thus, the problem that traditional ECM has, is avoided.The environmental conditions, which are represented by a large number of parameters, are also an important aspect of extreme calculation. Whereas some of them are treated as stochastic values, some are considered deterministic and, therefore the existence of uncertainties in their measured/estimated values is inevitable. These uncertainties are addressed by adopting values recommended by standards and guidelines and, in practice, it is often necessary to be conservative when there is a lack of information about the specific site studied. Therefore, the understanding of the impact that these uncertainties can have on the loads/responses that govern the design of offshore structures, especially wind turbines, is of great relevance. In this work, the influence of uncertainty in the wind shear coefficient (WSC) is studied. This parameter is directly related to one critical environmental condition i. e. wind speed at hub height, and its influence in power production and fatigue loads has been documented in the literature, but, few cases have addressed their influence in bottom fixed OWT responses.This work seeks to highlight the relevance of an accurate selection of shear coefficient and, its influence on the probabilistic analysis of a bottom fixed OWT taking into account that considerable variations from recommended values may occur. Through the use of coupled simulations in FAST, the NREL 5MW wind turbine will be subjected to varying wind shear conditions, and the corresponding 50-yr long-term responses will be calculated considering the MECM to take into account the influence of the wind turbine survival mode. The extreme values are fitted from a Global Maxima Method (GMM). Finally, it is sought to relate the uncertainty in a relevant input parameter (i. e. WSC) with the uncertainties propagated to the output parameters (i. e. extrapolated long-term extreme responses).Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte