Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The objective of the study was to describe the total postlarval length of Trichomycterus rivulatus Valenciennes, 1846 (suche) under controlled conditions. A total of 887 postlarvae of T. rivalatus after 25 days post-hatching was used as biological material. Water quality (temperature, dissolved oxygen and pH) was controlled. Before each feeding, siphoning was done to remove food debris and 90% of the water volume was replaced in all treatments. Growth (total length) was measured with a millimeter ruler (precision ± 0.01) at the beginning and end of the experimental phase. Survival for each experimental treatment before live feed supply was: T2 = 99.66% > T1 = 98.97% > T3 = 97.63%. At 21 days the postlarvae showed an average total length of 21.6 ± 0.51 mm, while at 45 days the total length was 30.53 ± 0.52 mm. A statistical difference was found between the total length at 21 and 45 days: t = -47.80 and p value = 0. The description of the total post-larval length of T. rivalatus under controlled conditions indicated that feeding with Daphnia pulex Linnaeus, 1758 + copepods presented the highest mortality. Choking was observed in the dead individuals. Also, as the number of days increased, there was growth in the postlarvae. It was concluded that the type of live food did not influence the total length of T. rivalatus postlarvae and, after 45 days, growth was significant.

In the COVID-19 pandemic, the generation and composition of municipal solid waste could vary. This study investigated the quantity and composition of municipal solid waste in times of the COVID-19 pandemic in the Madeán Town Center, Madeán District, Yauyos Province, Lima Region, Peru. The total solid waste was separated into eight fractions: paper / cardboard, plastics, organic, textile/leather, metals, electricity/electronics, glass, and others. Its percentage composition by weight was determined for six weeks between September and October 2020. The results showed that the average amount of weekly solid waste was 466.46 Kg ± 82.99 Kg. Regarding the composition, the organic fraction represents the largest part with 75.07%. In addition, in the Populated Center far from the capital, there is evidence of a minimal generation of bio contaminated waste, with a weekly average of 0.3 Kg ± 0.13 Kg, and 1.82 Kg collected throughout the study in the COVID-19 pandemic season. On the other hand, single-use plastics and disposable papers represent a large percentage compared to the recyclable part. In conclusion,the organic fraction exceeds the percentage of various studies in Peru concerning the pre- COVID-19 era. However, the bio contaminated waste generated is minimal; single-use plastics and disposable papers were higher than the recyclable part. Therefore, changes in the consumption of the inhabitants have impacted changes in the composition of solid waste. Keywords: biocontamination – organic fraction – plastic – recyclable

The objective of the study was to describe the environmental cost of the biodegradable transformation coefficient in effluents from oxidation ponds, Ica, Peru. In January and February 2023, effluents from the oxidation ponds of Angostura Limón, Yaurilla and Pueblo Nuevo were sampled. Biochemical oxygen demand (BOD5.20) and chemical oxygen demand (COD) were determined where the concentrations were compared with the maximum permissible limit of Supreme Decree 004-2017 MINAM - Peru. With the data, the environmental cost was estimated by a quotient between the cost of assessment (COA) and the regulatory prevention cost (CONP). The values were BOD5.20 = 203.1 mg.L-1 and COD = 405.0 (Angostura Limón), BOD5.20 = 273.1 mg.L-1 and COD = 450.8 mg.L-1 (Yaurilla) and BOD5.20 = 366.5 mg.L-1 and COD = 628.0 mg.L-1 (Pueblo Nuevo). The environmental cost was equal to 0. The BOD5.20 and COD values exceeded the normative permissible limit: 5.0 mg.L-1 (BOD5.20) and 20.0 mg.L-1 (COD) because there was a high content of organic matter that did not biodegrade before the partial oxygen concentrations. The effluents are shown as a resource of limiting value. It is concluded that the concentrations of BOD5.20 indicated that there was biodegradability in the oxidation ponds, but the content of organic matter is high where the retention time for its degradation is insufficient and this dynamic influences the limitation of the use of the effluents because their treatment was not adequate.

The objective of the study was to describe chaos and creativity from a methodological vocabulary in the embodied learning of the research seedbed. From January to December 2022, a pilot project called "Formándose y Formando" was carried out with four research seedlings of the Universidad Nacional ¨San Luis Gonzaga¨, Ica, Peru. Four pedagogical dimensions were established to describe conceptualization criteria in three stages and then the embodied learning of the methodological vocabulary was considered with five structures in a pedagogical model: title, introduction, objectives, measurement and proposal improvement. Conceptualization criteria were recognized for two levels: practical and theoretical of the methodological vocabulary. The bigraphy yielded as percentage of variance the title (46.15%), introduction (23.22%), objectives (20.18%), methods (9.64%) and proposal improvement (0.81%). It was concluded, that the description of the chaos and creativity of the methodological vocabulary in the embodied learning of the research seedbed through the pedagogical model defined the embodiment of a cognition and learning where the knowledge integration skills were measured with conceptualization criteria.

The inadequate treatment of urban waste in landfills represents an environmental risk for agricultural soils where their edaphological properties can be modified. The aim of the study was to evaluate organic matter and pH in agricultural soil in front of the Quitasol dump in the city of Abancay, Apurímac, Peru. Three sampling points (PM1, PM2, PM3) of the agricultural soil where organic matter (OM) and pH were determined were selected by means of a random probability sampling. The results were: PM1 (MO = 1.69%; pH = 7.05), PM2 (MO = 1.12%; pH = 7.06) and PM3 (MO = 0.30%; pH = 7.26). The percentage of OM ranged from the medium to low range where there were statistically significant differences between the three sampling points. The pH values were on the neutral scale. It is concluded that the use value of the agricultural land near the Quitasol dump is limited according to the organic matter and the pH outside the interchangeable range of majority and minority elements for productivity.

The qualities of polypropylene fi bers accompanied by ideal materials such as concrete, have brought solid and resistant structures to all types of construction such as pavements, tunnels, roads, among others. The purpose of this paper is to examine the behavior of concrete reinforced with different types of fi ber, including polypropylene fi ber, in order to know its reaction to mechanical processes. A review of 50 articles was carried out between 2010 and 2021, including Scopus, Scielo, ScienceDirect and EBSCO databases, analyzing the effects of fi bers and their infl uence on the compressive strength of concrete. In order to know the improvements in the strength of concrete using polypropylene fi ber, the results obtained with different dosages of this fi ber are presented. We conclude that the use of polypropylene fi ber generates the following changes in the properties of the concrete: 1) Increase in its tensile capacity; 2) Decrease in the workability of the concrete and, 3) Increased ductility of the concrete. Keywords: Compressive strength – concrete – polypropylene fi bers

This article is the product of academic research, personal refl ections, professional experiences, and normative and technical proposals of the author. It is a qualitative approximation to the study and systematization of public housing policies in Peru in the period 1946-2021, by representative institutions, by type of policies, and by type of political and economic reforms; and also is a proposal of some contributions for a public housing policy in the country 2021- 2030, with housing programs differentiated by social strata, by city size, and by natural regions. Keywords: housing – public housing policies – public policies

The aim of the study was to describe theoretical-practical tools of the professional teaching and learning process as a category of university teaching. The study was carried out from January to June 2021, where teaching was considered as the first university mission, the category that refers to the professional process of teaching and learning. In this category, six theoreticalpractical tools are mentioned: 1st) establishes the didactic strategies, 2nd) selects the content, 3rd) identifies the learning resources, 4th) schedules the activities, 5th), considers the type of evaluation, and 6th) the learning outcome is diagnostic and then conceptualized for description. It is indicated that every process aims to optimize methods and techniques in the teaching and learning relationship to move between skill levels. In the process of updating and relevancy of knowledge, a definition of the practice to be evaluated is needed so that the program exercised is transcendental. Likewise, the effectiveness of the identification of resources requires the remodeling of educational practice through digital technologies. The operability of planning needs to show positive effects from a dialogic teaching. For its part, the demonstration of competencies on performance and capabilities consider the type of evaluation and the verification of knowledge is a critical issue. It is concluded that the theoretical-practical tools of the professional teaching and learning process as a category of university teaching is a complex process and can result in a contradiction to rhetoric when all construction and reconstruction of knowledge is expressed. Keywords: competence – didactic strategies – evaluation – methodological processes – university teaching

The aim of the study was to evaluate digital technological competence through the Moodle platform in university teaching during COVID 19. The study was carried out between May and July 2021 with students with a master’s degree in health sciences and a doctorate in science, technology and the environment, where digital technological competences were recognized from the activity or resource (chat, questionnaire, forum and task) that were added from the visualization in the Moodle virtual teaching platform. Statistically signifi cant differences were found in the level of response for the master’s and doctoral programs; where there was no alignment of discrimination of means in both programs and in the case of applicants for a master’s degree in science, the level of response to information from an activity or resource was better. Chat and forum were the lowest frequency activities. It is concluded that the COVID-19 pandemic generates concern in education, since there are digital access gaps, and deficient use from the activities shown by the Moodle teaching platform. In addition, digital technological competence in university teaching for both postgraduate programs was valued as limited, since the low number of applicants who showed an immediate level of response, supports the idea that the digital divide from the answers of technological resources prevents integration, the development of social practices and that are related to formative learning. Keywords: COVID 19 – digital competence – teaching – technology – university

The aim of the study was to analyze dimensions of value in the scientific manuscript. The study was conducted between May and July 2021, where  the ScienceDirect database was accessed. The last fi ve years of viewing was fi ltered and only the article publication types referred to the review and research. Through means of a systematic random probability sampling, 25 research articles were selected. 5% of the citations for each of the scientific articles of selection were analyzed and then the interpretation from the scientific problematization, statistical model of the selection variables, act and power of the scientific argumentation for four axiological barriers of dimensions of value that identify the scientific publication. It was observed in the scientific articles that the value dimensions of the axiological barriers showed coding of accepted responses. Likewise, the need to understand a hermeneutical key of the scientific manuscript is shown and with this, the search for the scientific effort for its recognition from how the manuscript should be written is considered. It is concluded that the dimensions of value from axiological barriers make it possible to understand the nature of the impact of scientific articles, since they determine the methodological domain of scientific research and its way of communicating it; however, the contributing analysis and guide for its probable publication is guaranteed from the hermeneutics of questions for each scientific manuscript. Keywords: research characteristics – methodological processes – scientific publication – scientific writing