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1
artículo
Publicado 2023
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In recent years, the consumption of beverages has increased; however, the excessive consumption of processed and packaged foods with a high sugar content is detrimental to human health as it has led to an increase in various metabolic diseases, which is why it is essential to introduce into the food chain new options of beverages enriched with fruit pulp, rich in polyphenolic compounds and antioxidants. This research sought to develop a functional beverage based on soybean juice and aguaymanto pulp sweetened with stevia, for which nine treatments were formulated consisting of 70, 80 and 90% soybean juice, 30, 20 and 10% aguaymanto pulp and 0.08, 0.10 and 0.12% stevia, and their physicochemical characteristics, sensory acceptability and bioactive composition were evaluated. The results showed that treatment 3 presented the highest sensory acceptability by the panelists with a score of 3.3...
2
artículo
Publicado 2012
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The aim of the present work was to optimize the sensorial and technological features of ice cream. The experimental work was performed in two stages: 1) optimization of lactose enzymatic hydrolysis, and 2) optimization of the process and product. For the first stage a complete factorial design was developed, optimized using both response surface and the steepest ascent method. In the second stage a mixture design was performed, combining the process variables. The product with the best sensorial acceptance, high yield and low cost was selected. The acceptance of the product was developed by an untrained taster’s panel. As a main result the sensorial and technological features of the final product were improved, establishing the optimum parameters for its elaboration.
3
artículo
Publicado 2012
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The aim of the present work was to optimize the sensorial and technological features of ice cream. The experimental work was performed in two stages: 1) optimization of lactose enzymatic hydrolysis, and 2) optimization of the process and product. For the first stage a complete factorial design was developed, optimized using both response surface and the steepest ascent method. In the second stage a mixture design was performed, combining the process variables. The product with the best sensorial acceptance, high yield and low cost was selected. The acceptance of the product was developed by an untrained taster’s panel. As a main result the sensorial and technological features of the final product were improved, establishing the optimum parameters for its elaboration.
4
artículo
Publicado 2019
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The effects of organic and conventional crop systems on chemical composition, antioxidant activity and functional properties were evaluated in white and dark chia (Salvia hispanica L.) seeds. The organic system reduced the total protein content, and increased the total carbohydrates but did not change polyunsaturated fatty acids, total phenolic or flavonoids. Organic white chia seeds showed the best techno-functional properties. The antioxidant capacity of chia extracts varied in relation to the chemical complexity and differential rate kinetics of different assays. Extractable total phenolic acids and antioxidant capacity were better in organic white chia seeds. In this first approach, we have demonstrated that the organic white chia seed has a better total antioxidant capacity measured by direct quencher approaches than its conventionally-grown counterpart. To summarize, we conclude th...
5
artículo
Publicado 2009
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Los problemas en el sector anterior son muy comunes en nuestra práctica profesional y cobra vital importancia el realizar una adecuada rehabilitación en estos casos; no podemos hacer una buena rehabilitación si no conocemos las características básicas tanto estéticas como funcionales. Hoy las resinas compuestas son una alternativa válida para la reconstrucción del sector anterior, ya que nos brindan una buena posibilidad conservadora y estética, pero independientemente del material a utilizar debemos basarnos en ciertas reglas o parámetros para realizar una adecuada rehabilitación. En el presente artículo se detallan los criterios básicos a tomar en cuenta para reconstruir el sector anterior así como la técnica al utilizar resinas compuestas.
6
artículo
Publicado 2009
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The anterior sector problems are very common in our professional practice and became vital importance to make a suitable rehabilitation in these cases; we can not do a good rehabilitation if we do not know the basic characteristics, both aesthetic and functional. Today the composites are a valid alternative for the restoration of the anterior sector, since they offer to us a conservative and aesthetic possibility, but independently of the material to use we have to based on certain rules or parameters to realize a suitable rehabilitation. In this article the basic criteria to keep in mind are detailed to restore the anterior sector as well as the skills on having used composites.
7
objeto de conferencia
Publicado 2020
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ABSTRACT This work evaluated the influence of the concentration of NaOH (100, 200 and 300 g/L NaOH) in the mercerization process at 25 °C for 1 h, and of the percentage (15, 20 and 25% m/m) of Mauritia flexuosa fibers on impact resistance in a polyester matrix composite. The polyester matrix composite was obtained by the compression molding process, at a constant pressure of 24 MPa. The obtained plates had a dimension of 130 mm long x 80 mm wide x 3.4 mm thick. Specimens for the impact assay were extracted from the obtained plates under the EN ISO 179-1 standard. Likewise, the fiber-reinforced composites without treatment were also evaluated, all the fibers were characterized before and after the NaOH treatment by means of the chemical characterization of the fiber, absorption percentage, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy ( FT-IR). The result...
8
artículo
Tooth wear is the loss of hard tissue of multiple aetiology and may be due to functional or parafunctional factors. Depending on this, a restorative treatment should be chosen based on the severity of the wear, as it can result in loss of vertical dimension of occlusion (VOD), tooth sensitivity, and decreased quality of life. In these cases, the choice of restoration strategy must follow evidence-based treatment protocols, which include direct and indirect restoration techniques, as well as minimally invasive treatments based on composite resins that emerge as an alternative to conventional restorations of ceramics. This clinical case describes the treatment of a patient with severe dental wear through oral rehabilitation with composite resins through direct and indirect techniques, with the aim of preserving the tooth structure as much as possible and having greater aesthetic-functional...
9
artículo
Publicado 2021
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El deterioro de las construcciones hechas con ignimbrita en el centro histórico de Arequipa, es un problema causado por el intemperismo, emisión de contaminantes industriales y biológicos, afectando su preservación. Se evaluó aplicar a la ignimbrita, polisiloxano funcionalizado con nanopartículas de plata (PXS-AgNPs), como recubrimiento para disminuir su porosidad, evitar su degradación y darle un efecto protector a su superficie.Las nanopartículas de plata (AgNPs) se sintetizaron, por reducción de nitrato de plata (AgNO3) con borohidruro de sodio (NaBH4), el polisiloxano se sintetizó por hidrólisis del clorosilano en agua y éter dietílico; que fue funcionalizado con AgNPs, mezclando soluciones acuosas de PXS y de AgNPs, obteniéndose un gel de color amarillo lechoso. Se aplicó PXSAgNPs a la superficie de la ignimbrita y se realizaron pruebas de adsorción con solución de ...
10
artículo
Publicado 2020
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In the present investigation we present a polysiloxane composite functionalized with silver nanoparticles (NPs-Ag). NPs-Ag was synthesized, by reduction of a silver nitrate solution (AgNO3) with sodium borohydride (NaBH4), the NPs-Ag were characterized by the UVvisible spectrophotometric method, finding that between 400 - 410 nm the typical peak of NPs-Ag by surface plasmon resonance. In the Dynamic Light Scattering (DLS) analysis of the NPs-Ag, a polydisperse distribution was found with two populations of 59.78 nm in 70% and 4.33 nm in 30%. Subsequently, the polysiloxane gel was synthesized by hydrolyzing chlorosilane, using diethyl ether as the solvent, the obtained polysiloxane was characterized by infrared Fourier transform spectrophotometry (FTIR). In the spectrum peaks are observed in the region of 1258.88 cm-1 corresponding to methyl, between 1000 - 1100 cm-1 a peak corresponding ...
11
artículo
Publicado 2017
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The alterations of the lipid metabolism and the uncertainty at the moment of selecting beneficial foods to the human body lead to the investigation of omega fatty acids. The study is based on the evaluation of the effect of three preparation methods of chía seed, before getting the oil through two extraction methods and the characterization of the lipid fraction of chia seed (Salvia hispánica L.) from Colta-Ecuador. The oil yield of the conditioned seeds showed statistical differences. Regarding the extraction method, the differences were highly significant, the use of ether in the Soxhlet equipment showed the superiority in the oil performance in a relation of approximately 2:1 versus immersion in hexane. The presence and the content of fatty acids was determined by the use of a gas chromatograph with FiD detector Agilent Technologies 5975C brand, fatty acids were separated with a cap...
12
artículo
Publicado 2025
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The main campus of the National University of San Marcos (UNMSM), located in Lima, Peru, has green areas that function as refuges for a significant diversity of birds. The aim of this research was to determine the species composition of the avifauna present on the main campus of the National University of San Marcos, Lima, Peru. Observations were carried out between August 2024 and July 2025, during the morning and afternoon hours. Thirty-three species were recorded, distributed across 10 orders and 18 families, with the Passeriformes order and the Thraupidae family predominating. The most representative trophic guilds were granivores and insectivores equally (27.3%), which is consistent with patterns typically observed in urban environments. Furthermore, the adaptation of Chordeiles acutipennis (Hermann, 1783) to archaeological sites on campus was documented, highlighting the importance...
13
artículo
Publicado 2017
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The competence of the European States in the field of international relations seems to conceive at the present time as an all-embracing faculty, which embraces all responsibility for any activity with external significance. In the Spanish case, this trend has meant a return to the prevailing conception during the primary stage of constitutional development, and refers to coverage in an expansive reading of the State’s competency title on international relations and on the functions of international treaties and Direction Foreign policy constitutionally conferred on the Government.
14
tesis de grado
Antecedentes: Los cambios de estilo de vida y la mayor valoración de una dieta saludable ha permitido el desarrollo de alimentos y bebidas funcionales. Estas bebidas funcionales, sean naturales o artificiales, contienen sustancias benéficas para la salud o potencian algún aspecto de esta. Además, se consumen con cierta frecuencia y presentan pigmentos relacionados a sus componentes. No existe información sobre el efecto que puede producir sobre restauraciones de composite. Objetivo: Evaluar la influencia de bebidas funcionales en el color de un composite de nanorelleno. Materiales y Métodos: Se confeccionaron 60 especímenes de composites (Filtek™ Z350 XT, 3M ESPE, St. Paul, EEUU) color A2 (7 mm diámetro x 2 mm altura). Los especímenes fueron inmersos en las bebidas (Vitaenergía, ON, No Stress, Amalaki, café y agua destilada) por 30 minutos durante 28 días. El registro del c...
15
artículo
Publicado 2025
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Bulk-fill composite resins have emerged as a key innovation in restorative dentistry, offering an efficient and modern alternative for direct dental restorations. These resins allow for the placement of thicker layers, reducing clinical time. Among their main features are their adaptability, adequate depth of polymerization, and mechanical properties, which meet clinical requirements for functional and durable restorations. The clinical benefits of bulk-fill resins include reduced polymerization shrinkage stress and simplified handling, making them particularly useful for deep cavity restorations. However, despite these advantages, controversies have arisen regarding their long-term performance, such as color stability and wear resistance in areas of high occlusal load. This article reviews the fundamental characteristics of bulk-fill resins, their clinical benefits, and the controversie...
16
artículo
Publicado 2023
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The aim of this study was to evaluate the effect of the genotype on the deposition curve of the chemical components and fatty acid profile of carcass of guinea pigs of Peru and Cieneguilla genotypes. Forty-eight male guinea pigs (24 per genotype), randomly distributed in pens with three animals each per genotype were used. Management and feeding protocols, up to 32 wk of age, were similar for both genotypes. The deposition curve of the chemical components was determined using the Gompertz equation. Data of the fatty acid profile were submitted to analysis of varianza under a Randomized Complete Block Design using the SAS Studio Environment software, with a significance level of α = 0.05. The results showed that the asymptote of the moisture and protein content in the carcass of the Peru genotype was higher (P < 0.05) than that of Cieneguilla genotype, but not in the fat content, whic...
17
artículo
This work studies the dependence of Cs-137 root uptake on the structure of landscape, especially on the properties of soils, under controlled conditions. Researches were carried out at various levels of Cs-137 contamination (from 20 up 1000 kBq/m²), with five different types of soils, which differ in texture and granulometric composition. The results showed that transfer factor (TF) values of Cs-137 differ 5 times for the natural grassy coenoses. The correlation between Cs-137 TF values and granulometric composition of soil was determined for both automorphic and hydromorphic mineral soils.
18
artículo
Publicado 2021
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The Rietveld refinement method has taken high relevance since its creation. Nowadays, it is an useful tool in many fields of industry, materials science, and technology. For these reasons, it becomes a need for scientists and engineers whom pretend to use it for proper analysis of their materials. However, the initiation in the method can be slow, taking into account the accelerated rhythm of the research and economic demands. Thus, this work is an intend to fulfill this hole, providing the basic foundations and methodology of the Rietveld refinement in a brief way, this along with the results of its application in superconducting samples of Yttrium Barium Copper Oxide and magnesium diboride, and functional magnetic nanoadsorbents of maghemite and a multiphasic composite (iron oxide, hydroxyapatite and secondary phases). In the process, an in-detail protocol was designed and provided. It...
19
artículo
Publicado 2016
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The potato (Solanum tuberosum) is an important source of starch which is underused in Peru, as are mainly imported potato starch, for has not been achieved yet, industrialization starch extraction is a success. This study aimed to obtain, characterize and modify chemically by acetylation, starch of a commercial potato variety, Unique. Extraction was performed with water and chemical modification was performed by acetylation using acetic anhydride at different levels (% v/w starch): 5, 10 y 15%. Native starch and modified starch were characterized: proximate composition, clear gel, apparent viscosity and stability to the freeze, also the percentage of acetyl groups (GA) was measured. The extraction yield was 16.5% and the apparent viscosity of native potato starch was 25000 mPas. Also starch modified with 15% acetylation for application in a cream ice cream because of their functional ...
20
artículo
Publicado 2016
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The potato (Solanum tuberosum) is an important source of starch which is underused in Peru, as are mainly imported potato starch, for has not been achieved yet, industrialization starch extraction is a success. This study aimed to obtain, characterize and modify chemically by acetylation, starch of a commercial potato variety, Unique. Extraction was performed with water and chemical modification was performed by acetylation using acetic anhydride at different levels (% v/w starch): 5, 10 y 15%. Native starch and modified starch were characterized: proximate composition, clear gel, apparent viscosity and stability to the freeze, also the percentage of acetyl groups (GA) was measured. The extraction yield was 16.5% and the apparent viscosity of native potato starch was 25000 mPas. Also starch modified with 15% acetylation for application in a cream ice cream because of their functional ...
