Repositorio institucional - Concytec
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Guía Alicia 2.0
No full textPenúltima versión de la Guia Alicia, publicada en mayo de 2020. Presenta los criterios de implementación de repositorios institucionales en el Perú, respecto a proveedores, herramientas (software), gestión (políticas, comunidades, colecciones, flujos de trabajo), metadatos, evaluación (calidad), entre otros criterios para su puesta en servicio en cumplimiento con la Ley Nº 30035, Ley que regula el Repositorio Nacional Digital de Ciencia, Tecnología e Innovación de Acceso Abierto (ALICIA)
Libros & Ciencias: Revista de divulgación científica (N° 1 - Diciembre 2020)
No full textComunica al público no especializado temas científicos y tecnológicos que despiertan el interés actual. Este primer número se enfoca en el cambio climático, uno de los temas que despierta mayor interés en la comunidad científica y la ciudadanía en general pues sus consecuencias ya están generando cambios drásticos en nuestro territorio y en el mundo. Así, desde hace algunos años, la ciudadanía ha tomado mayor consciencia de la vulnerabilidad en la que está frente a los impactos del cambio climático principalmente por el esfuerzo e iniciativa de algunos científicos, organizaciones internacionales y activistas; sin embargo, muchos no conocen los principios científicos que gobiernan este fenómeno, aquellos que nos permitirán desarrollar medidas para la adaptación de nuestras poblaciones humanas, y tampoco han tomado consciencia de las formas en las que todas y todos podemos mitigar nuestras emisiones y no contribuir a la acumulación de gases de efecto invernadero en nuestra atmósfera. En este contexto, Libros&Ciencias N°1 muestra el panorama actual de la ciencia en relación a este fenómeno
Natural fibers as reinforcement additives for geopolymers – A review of potential eco-friendly applications to the construction industry
No full textThe construction industry is responsible not only for the consumption of huge amounts of natural resources but also for the emission of large quantities of CO2. Geopolymers have emerged as an environmentally friendly alternative for conventional construction materials since they can be produced from industrial wastes. Similarly to ordinary concrete, geopolymers can also improve their mechanical properties when reinforced with fibers. This paper presents a review of recent advances in the production of natural fiber-reinforced geopolymers produced from industrial by-products and waste materials as promising sustainable construction materials. Regarding the use of industrial wastes, this paper reports the use of fly ash, ground granulated blast furnace slag, construction and demolition wastes and mine tailings for the production of high strength geopolymers. At the same time, a survey of successful reinforcement with natural fibers (from plants such as pineapple leaf, sisal, linen, flax, sweet sorghum, and cotton) is also reported. In this respect, it has been found that the type of fiber, dimensions, amount and pretreatment of fibers affect the final properties of the resulting composites. Moreover, layer reinforcement using woven and non-woven layers of natural fibers seem to be more effective than short fibers randomly oriented.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Caracterización físico-química de dos formas de compostaje generados a partir de residuos de la industria palmitera APROPAL – distrito de Caynarachi, 2019
No full textLa presente investigación caracterizó físico-químicamente dos formas de compostaje, generados de fuentes de residuos de palmito provenientes de la Cooperativa Agroindustrial del Palmito APROPAL Ltda. en el distrito de Caynarachi, para conocer su potencial como sustrato para la productividad de Pleurotus sp. Se utilizó residuos de palmito (cáscaras de palmito y puntas fibrosas) en las siguientes proporciones: M1: 100% residuos de palmito y M2: 85% residuos de palmito + 15% gallinaza, empleando dos formas de compostaje (en forma de franjas, y en forma apilada). Los resultados indicaron que, en el proceso de compostaje muestra fases: Mesófila, Termófila, Mesófila II y de Maduración, identificadas en los días 1, 6, 8 y 15 días respectivamente para todos los tratamientos. Los mejores resultados se presentaron en el tratamiento 3 (forma apilado + 100% residuos de palmito) con valores de 5.50 pH, 25.76% celulosa, 10.40% hemicelulosa, 37.04% lignina, 0.37% nitrógeno, 60.64 ppm fósforo, 3700.25 ppm potasio, 4.27% carbono, 8.20 meq/100g Ca+2, 3.74 meq/100g Mg+2, 0.19 meq/100g Na+, 7.36% M.O, 2.70 dS/m C.E., 19.93 meq/100g C.I.C. y 33.50% ceniza. El T1 (forma franjas + 100% residuos de palmito) puede ser considerado para la producción de Pleurotus sp, siempre y cuando sea a partir de los 15 días. Los tratamientos 2 y 4 no pueden ser considerados para la producción de Pleurotus sp.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Social networks of the peruvian ministry of health in the combat against anemia: Qualitative-quantitative study of a promotional preventive video
No full textCender U. Quispe-Juli recibe financiamiento del Fondo Nacional de Desarrollo Cient?fico, Tecnol?gico y de Innovaci?n Tecnol?gica (FONDECYT).Childhood anemia is a public health problem in Peru. A variety of preventive strategies are being developed, among them the use of social networks. Little evidence is available about the best ways to interact with audiences in this space. The purpose of the study was to explore the perception of users of social networks of the Peruvian Ministry of Health about a video promoting food to reduce the risk of childhood anemia and estimate the scope and interaction it achieved through the social networks. An exploratory qualitative-quantitative study was conducted of an intervention based on a music video disseminated by the Ministry of Health in the social networks Facebook, Twitter and YouTube. Most of the users commenting on the video (58 / 77) in Facebook reported a positive perception. The largest number of replays was reached at four months' follow-up in Facebook (364 000 replays), trebling the results of Twitter and YouTube together. The broadest scope was achieved during the first week. The highest interaction rate at four months occurred in Facebook (7.1%), followed by Twitter (5.2%) and YouTube (0.3%). The greatest scope and interaction rate of the study video occurred in Facebook. Perception was positive, but the interaction rate was low. Social networks are a swift though ephemeral form of communication with a great potential in public health. © 2020, Centro Nacional de Informacion de Ciencias Medicas. All rights reserved.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Adaptive EWMA-S(2)control charts with adaptive smoothing parameter
No full textMemory charts like EWMA-S(2)or CUSUM-S(2)are designed to detect a particular change in the process variance efficiently. However, the charts could be inefficient to detect some other shifts. To overcome this constraint, control charts with adaptive schemes that are efficient for a wide range of shifts can be used. This work proposes new adaptive EWMA charts for the dispersion (AEWMA-S-2) based on an adaptive smoothing parameter that relates its value to the potential shift of the process. A Markov chain approach is used to optimize its design. A simulation experiment shows the advantage of the proposed charts.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Drying Accelerators to Enhance Processing and Properties: Ethanol, Isopropanol, Acetone and Acetic Acid as Pre-treatments to Convective Drying of Pumpkin
No full textDifferent drying accelerators were studied to improve vegetable drying: acetone (AC), ethanol (ET), isopropanol (ISO) and acetic acid (AA). Pre-treatments were performed by immersion of pumpkin cylinders. Convective drying was performed at 40 degrees C and air velocity 1 m/s. Different aspects were evaluated: drying kinetics, structural changes (microstructure and macrostructure), thermal profile and viscoelastic and rehydration behaviours. The microstructure was modified by pre-treatments, being more pronounced with AC and AA. Thinner cell walls, changes on turgor and extraction of components and air were reported, affecting the mass transfer. Moreover, the microstructural changes reinforced anisotropy and also affected the macrostructure, changing the viscoelastic behaviour. All pre-treatments resulted in a super-diffusive behaviour, decreasing the drying time from 9% (ISO) to 22% (AC). Possible relations were discussed among the compounds' physical properties, sample temperature profile, drying kinetics and equilibrium moisture. Rehydration was improved by ET and ISO, but impaired by AA. Although AC accelerates drying, it did not affect the rehydration. The viscoelasticity reflected the structure and composition, with the pre-treatments with higher structure modifications (AA and AC) losing elastic properties. In conclusion, the pre-treatments with isopropanol and ethanol showed better results, improving drying and rehydration, and are thus recommended.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Growth performance, oxidative stress, and antioxidant capacity of newly weaned piglets fed dietary peroxidized lipids with vitamin E or phytogenic compounds in drinking water
No full textObjective: This study evaluated the use of vitamin E and phytogenic compounds in drinking water on growth performance, oxidative stress, and immune status of piglets fed peroxidized lipids. Materials and Methods: In a 35-d study, 21-d-old weaned piglets (n = 96; 6.10 +/- 0.64 kg of BW) were assigned within sex and BW blocks to 1 of 4 treatments, using 24 pens (4 pigs per pen; 6 replications per treatment). Diets contained either 6% soybean oil or 6% peroxidized soybean oil. Pigs fed peroxidized soybean oil received drinking water without (control) or with supplemental vitamin E (100 IU/L of RRR-alpha-tocopherol) or phytogenic compounds (60 mu L/L for wk 1 and 30 mu L/L for wk 2 to 5). Results and Discussion: Peroxidized soybean oil decreased (P < 0.001) final BW (18.2 vs. 21.6 kg) and ADG (346 vs. 441 g/d) and tended to decrease ADFI (P = 0.14; 542 vs. 617 g/d) and G:F (P = 0.07; 645 vs. 715 g/kg). Peroxidation decreased serum vitamin E concentrations (P = 0.03), which could be restored (P = 0.01) by vitamin E in the water, but not phytogenic compounds. Peroxidized soybean oil decreased serum 8-hydroxydeoxy-guanosine, increased serum protein carbonyl, and had no effects on serum malondialdehyde or cytokines. Implications and Applications: Peroxidized soybean oil reduced growth performance of weaned nursery pigs, which did not appear to be related to oxidative stress or immune status. The negative effects of peroxidized soybean oil on animal performance could not be improved by supplementation of vitamin E or phytogenic compounds in the drinking water.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy
Magnetic skyrmion states in cobalt nanodisk
No full textInternal magnetic states and changes in the texture of the magnetization in cobalt nanodisks have been studied using micromagnetic simulations under two different initial conditions: a nucleated Bloch type skyrmion placed at the center of the cobalt disk and displaced 32 nm from the center. Analysis of simulation results clearly demonstrates that variations in values of the anisotropy (Ku) and Dzyaloshinskii-Moriya interaction (DMI) constants have strong influence on the internal magnetic states and the energy terms of the cobalt nanodisk. Of interest is the nucleation and stability of magnetic skyrmions as a function of the DMI constant. Micromagnetic analysis suggest that the interplay between demagnetizing, exchange and Dzyaloshinskii-Moriya energies induces a diagram with different textures of the magnetization including the Bloch and Néel type skyrmions, incomplete skyrmion and skyrmionium. If the initial Bloch skyrmion state is displaced 32 nm from the center, the diagram for the texture of the magnetization changes, creating a cycloid state for higher values of the DMI constant. The results have been discussed in function of the competition between the energy terms, and the initial magnetic states.Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica - Concyte
Potato starch-based films: Effects of glycerol and montmorillonite nanoclay concentration
No full textThe films can be obtained from renewable resources such as polysaccharides, proteins, and lipids. Potato starch is a polysaccharide found in abundance, low cost, biodegradable, edible, and can be obtained from agro-industrial waste. In the present study, biodegradable films were obtained from potato starch mixed with montmorillonite nanoclay (MMT) as crosslinking agent and glycerin as a plasticizer; and thus characterize properties such as: permeability to water vapor, solubility, thickness, functional groups by FTIR, analysis of the morphology by scanning electron microscopy (SEM), and mechanical properties. 9 mixtures combining different proportions of glycerol (1, 1.5 and 2 ml) with montmorillonite nanoclay (MMT) (0, 0.03 and 0.05 g) were prepared.Fondo Nacional de Desarrollo Científico y Tecnológico - Fondecy