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Silver enhances hematite nanoparticles based ethanol sensor response and selectivity at room temperature
No full textGas sensors are fundamental for continuous online monitoring of volatile organic com-pounds. Gas sensors based on semiconductor materials have demonstrated to be highly competitive, but are generally made of expensive materials and operate at high temperatures, which are draw-backs of these technologies. Herein is described a novel ethanol sensor for room temperature (25◦C) measurements based on hematite (α-Fe2O3 )/silver nanoparticles. The AgNPs were shown to increase the oxide semiconductor charge carrier density, but especially to enhance the ethanol adsorption rate boosting the selectivity and sensitivity, thus allowing quantification of ethanol vapor in 2–35 mg L−1 range with an excellent linear relationship. In addition, the α-Fe2O3/Ag 3.0 wt% nanocomposite is cheap, and easy to make and process, imparting high perspectives for real applications in breath analyzers and/or sensors in food and beverage industries. This work contributes to the advance of gas sensing at ambient temperature as a competitive alternative for quantification of conventional volatile organic compounds. © 2021 by the authors. Li-censee MDPI, Basel, Switzerland.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Trace element composition and U-Pb ages of cassiterite from the Bolivian tin belt
No full textThe Bolivian tin belt is a metallogenic province in the Eastern Cordillera of the Andes known for its Sn, W, Ag, and base metal deposits. Cassiterite, which is a major constituent in many magmatic-hydrothermal ore deposits from the Bolivian tin belt, can incorporate dozens of elements within its crystal lattice, making it a useful geological tracer mineral and also a potential host of critical elements. New U-Pb dating of cassiterite yields Late Triassic (Kellhuani deposit) and Late Oligocene to earliest Miocene (Viloco, Huanuni, and Llallagua deposits) ages. These ages confirm that Sn mineralization in the Bolivian tin belt occurred at least in two separate events during two major magmatic episodes apparently triggered by mantle upwelling, decompression melting, and basalt production promoting high heat flow into the overlying crust. The composition of studied hydrothermal cassiterite yields some geochemical trends that are attributed to its distance to the causative intrusion and/or level of emplacement. For example, cassiterite is generally enriched in Nb and Ta and yields higher Ti/Zr and Ti/Sc ratios in samples from xenothermal ore deposits located adjacent to intrusive complexes relative to shallow xenothermal and epithermal ore deposits. Therefore, these geochemical trends in cassiterite are useful tracers pointing to magmatic-hydrothermal centers. REE distribution in cassiterite was likely influenced by boiling processes, which resulted in tetrad-type irregularities. Cassiterite from the Bolivian tin belt is unattractive as a source for Nb (interquartile range [IQR] 4.84-0.037 ppm), Ta (IQR 0.0924-0.0126 ppm), and Ge (IQR 3.92-0.776 ppm). Some deposits, however, contain cassiterite relatively enriched in In (IQR 96.9-9.78 ppm, up to 1414 ppm) and Ga (IQR 92.1-3.03, up to 7437 ppm), that could constitute an attractive supplementary source for these elements in addition to sulfide minerals in the same deposits.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Gestión de datos de investigación en repositorios
Get PDFMenciona que entre los principales retos para los administradores de los repositorios digitales en todo tipo de organizaciones, es el que se relaciona con la necesidad de recopilar y preservar los datos de la investigación, así como el de asegurar su accesibilidad en el largo plazo. Por ello, es necesario seguir una ruta que asegure la adopción de buenas prácticas internacionales en cada una de las fases del ciclo de vida de los datos
Masi: A mechanical ventilator based on a manual resuscitator with telemedicine capabilities for patients with ARDS during the COVID-19 crisis
No full textThis work has been funded by the 055-2020-FONDECYT GRANT from the Peruvian government and the donations of the enterprises mentioned in our webpage: https://www.proyectomasi.pe/.In addition,the authors would like to thank to all the members of the Masi team, especially to all of the collaborators working at the five institutions involved in this project (BREIN, DIACSA, EAT, PUCP and Zolid). Without all of their effort, professionalism and sacrifice while working steadily during the pandemic; this device would have not existed.In this article, we introduce a portable and low-cost ventilator that could be rapidly manufactured, to meet the increasing demand of ventilators worldwide produced by COVID-19 pandemic. These ventilators should be rapidly deployable and with functional capabilities to manage COVID-19 patients with severe acute respiratory distress syndrome (ARDS). Our implementation offers robustness, safety and functionality absent in existing solutions to the ventilator shortage (i.e., telemonitoring, easy-to-disinfect, modularity) by maintaining simplicity. The design makes use of a manual resuscitator as the core respiration component activated by a compression mechanism which consist of two electronically controlled paddles. The quality measurements obtained after testing on a calibrated artificial lung demonstrate repeatability and accuracy exceeding human capabilities of manual ventilation. The complete design files are provided in the supplementary materials to facilitate ventilator production even in resource-limited settings. The implementation of this mechanical ventilator could eliminate device rationing or splitting to serve multiple patients on ICUs. (C) 2021 Pontificia Universidad Catolica del Peru. Published by Elsevier Ltd.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Monitoring shrimp growth with control charts in aquaculture
No full textThe data used in this work was provided by the Ecosac fish farm. The authors wish to express their appreciation for this and for all the support throughout the investigation, especially to the production engineer Grover Cedillo. This research has received financial support from the government of Peru, under contract 49-2018 of the project Proyecto de Mejoramiento y Ampliacion de los Servicios del Sistema Nacional de Ciencia, Tecnologia e Innovacion Tecnologica 8682PE, of the CON-CYTEC/FONDECYT/World Bank Group.This work proposes a method for the statistical monitoring of the weekly weight of shrimp in a fish farm. The design of control charts for shrimp growth presents several challenges, the main ones being the presence of trend and autocorrelation. Several control charts are proposed, the most efficient being a chart based on the residuals of a second order autoregression whose parameters vary with the week. A control chart with less computational complexity is also provided. It is simply based on growth rates and works well at detecting negative weight changes. Real data from a large shrimp farm has been used for both the design and the evaluation.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
T-CREo: A Twitter Credibility Analysis Framework
No full textThis research was supported by the FONDO NACIONAL DE DESARROLLO CIENTIFICO, TECNOLOGICO Y DE INNOVACION TECNOLOGICA ~ FONDECYT as an executing entity of CONSEJO NACIONAL DE CIENCIA, TECNOLOGIA E INNOVACION TECNOLOGICA - CONCYTEC under grant agreement No. 01-2019-FONDECYT-BM-INC.INV in the project RUTAS: Robots for Urban Tourism centers, Autonomous and Semantic-based.Social media and other platforms on Internet are commonly used to communicate and generate information. In many cases, this information is not validated, which makes it difficult to use and analyze. Although there exist studies focused on information validation, most of them are limited to specific scenarios. Thus, a more general and flexible architecture is needed, that can be adapted to user/developer requirements and be independent of the social media platform. We propose a framework to automatically and in real-time perform credibility analysis of posts on social media, based on three levels of credibility: Text, User, and Social. The general architecture of our framework is composed of a front-end, a light client proposed as a web plug-in for any browser; a back-end that implements the logic of the credibility model; and a third-party services module. We develop a first version of the proposed system, called T-CREo (Twitter CREdibility analysis framework) and evaluate its performance and scalability. In summary, the main contributions of this work are: the general framework design; a credibility model adaptable to various social networks, integrated into the framework; and T-CREo as a proof of concept that demonstrates the framework applicability and allows evaluating its performance for unstructured information sources; results show that T-CREo qualifies as a highly scalable real-time service. The future work includes the improvement of T-CREo implementation, to provide a robust architecture for the development of third-party applications, as well as the extension of the credibility model for considering bots detection, semantic analysis and multimedia analysis.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
The widely distributed, edible seaweeds in Peru, Chondracanthus chamissoi and Chondracanthus chamissoi f. glomeratus (Gigartinaceae, Rhodophyta), are morphologically diverse but not phylogenetically distinct
No full textConsejo Nacional de Ciencia, Tecnologia e Innovacion Tecnologica, Grant/Award Number: Convenio de Subvencion Nro. 017-2016-FONDECYTChondracanthus chamissoi is part of the diet of coastal people from Peru and is exported dehydrated to Asian countries for direct consumption. Although it is considered endemic to Peru and Chile, its range has extended to distant regions, such as Korea, Japan, and France. Using morphological and molecular approaches, we examined specimens from Peru assigned to C. chamissoi (including the taxon of uncertain status Chondracanthus glomeratus) to improve phylogenetic and geographical information and characterize its morphological variability. Twenty-one localities on the Peruvian coast were sampled, obtaining 102 COI and 27 rbcL sequences. To differentiate both entities, morphological characters such as thallus size, consistency, arrangement of main and secondary axes, branching patterns and location of reproductive structures, were analyzed on 46 specimens. While morphological characteristics are clearly contrasting among the two groups, both COI and rbcL phylogenies revealed a well-supported clade with no genetic differentiation between the two morphologies. Therefore, the phylogenies indicate that C. chamissoi and C. glomeratus form a single taxonomic entity with high morphological variability, large geographic distribution and at least two morphological forms. The smaller form of C. chamissoi can be identified as C. chamissoi f. glomeratus. Such morphological variability can be of interest for future aquaculture development.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Acid precipitation followed by microalgae (Chlorella vulgaris) cultivation as a new approach for poultry slaughterhouse wastewater treatment
No full textThis study was supported by the Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica (CONCYTEC) and the Fondo Nacional de Desarrollo Científico, Tecnológico y de Innovación Tecnológica (FONDECYT) - Perú. Grant N° 06-2019-FONDECYT-BM-INC.INV.Poultry slaughterhouse wastewater (PSW) contains high organic matter and nutrients requiring thus a special treatment before its final disposal. In this work, acid precipitation (H2SO4) followed by microalgae “Chlorella vulgaris” cultivation both in batch and continuous processes was studied as an alternative method for PSW treatment. By reducing the pH value of PSW from 6 to 7 to 4, about 80% of the total chemical oxygen demand (CODT) was removed as sludge. In the supernatant, the COD residual was efficiently removed (83%) by microalgae in the batch process, using an internal-loop concentric tube photobioreactor (4.5 L). Moreover, in continuous process, after 89 h, the COD value resulted lower than 200 mg L-1 and 1.2 g L-1 of microalgae in the output line. The proposed PSW treatment method is promising from economic and environmental viewpoints, since the microalgal biomass can be valued in a biorefinery context. © 2021 Elsevier LtdConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
An ecological overview of Prosopis pallida, one of the most adapted dryland species to extreme climate events
No full textFinancial support was provided by the Peruvian program CONCYTEC (163-2018-FONDECYT-BM-IADT-SE) granted to Dr. Pablo Salazar. RV was supported by the Spanish MEC project DIVERBOS ( CGL2011- 30285-C02-02 ) and ECO-MEDIT ( CGL2014-53236-R ), the project Ecología funcional de los bosques andaluces y predicciones sobre sus cambios futuros (For-Change) (UCO-27943) by Junta de Andalucía (Spain) , the project Funcionalidad y servicios ecosistémicos de los bosques andaluces y normarroquíes: relaciones con la diversidad vegetal y edáfica ante el cambio climático by Junta de Andalucía (Spain), all co-funded with European FEDER funds. RMNC was supported by the ISOPINE (UCO-1265298), ESPECTRAMED (CGL2017-86161-R) and SilvAdapt RED2018 102719 T projects. GML was supported by the Deutsche Forschungsgemeinschaft (DFG, ME 5087/1-1).Prosopis pallida (algarrobo) is a highly adapted species to extremely dry and wet conditions. Its geographic distribution at both sides of the Pacific Ocean is associated with its plastic response to El Niño event, an extreme climate event that changes precipitation regimes. In this review, we summarized the current knowledge of this versatile species based on scientific literature. Our analysis conducted identify three main research topics: geographical distribution, ecophysiology and population plasticity, and ecosystem services provision to guide the review in a methodological and unbiased way. In the geographical distribution section, we describe the origin, history, and native distribution of algarrobo, as well as the current distribution and the degree of invasiveness in some countries. In the ecophysiology and population plasticity section, we focus on the mechanisms used by algarrobo to avoid water stress during drought and maximize plant growth during El Niño. We discuss how this is reflected in the most important leaf functional traits, such as leaf mass per area (LMA) or gas exchange-related traits. We analyse the importance of phenotypic plasticity and intraspecific variability as adaptive ways to resist extreme rainfall and prolonged droughts on P. pallida growth during the last 50 years. Finally, we summarized the main ecosystem services and ecological benefits provided by P. pallida as well as its potential industrial uses. With this review, we wish to consolidate the current scientific knowledge of this species, to point out gaps of knowledge and suggest future research directions. As the world becomes a warmer place, P. pallida can be a key species to understand plant resilience to extreme events in dryland ecosystems. © 2021 Elsevier LtdConsejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Chemical Composition of Natural Fibers Using the Measured True Density. Case Study: Ichu Fibers
No full textThis paper was written in the context of the Project funded by CONCYTEC, under the contract number N° 103-2018 - FONDECYT-BM. The authors of this paper appreciate the financial support from the Peruvian Government.On any industry where the natural fibers are used, chemical composition of the fibers is an important parameter to determine, since it allows to predict the product quality. On the other hand, TAPPI standard developed a well described methodology to determine the chemical composition; however, their methodology is time and resource consuming, and furthermore it requires well trained specialist. An alternative to determine the chemical composition is to use the true density, since the density of the fiber constituents are different. In this study, we present a clear relation between the true density and the three major constituents (cellulose, lignin and extractives) with the fitting parameter R > 90%, for the Stipa obtusa base fibers. © 2021 Taylor & Francis.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte