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Toxicological and behavioral analyses indicates the safety of a biofertilizer in the non-target D. melanogaster
No full textThe demand for food to feed the growing world population has been promoting the indiscriminate use of chemical fertilizers, which can be detrimental to the environment. In order to maintain high crop productivity without damaging the ecosystem, biofertilizers have emerged as alternative to reduce the use of chemical fertilizers. So, environmentally safer biofertilizer can replace the exploitation of more toxic chemical fertilizer. Here, the fly Drosophila melanogaster was used to study the potential toxicity of the biofertilizer Beifort®. Flies were exposed to high concentrations of Beifort® in the diet (1.8 mL/L, 9.0 mL/L and 18 mL/L), and morphological and behavioral endpoints of toxicity were analyzed (development from egg to adult age, flies longevity, climbing performance, memory and learning of an associative learning, larvae digestive tract damage and plasmid DNA break). Beifort® did not modify flies development, survival, digestive track cell damage, locomotor activity or memory. Beifort® did not induce DNA breakage in vitro and had no toxicity to the non-target D. melanogaster after in vivo exposure. Thus, in addition of promoting the sustainable use of agricultural wastes, the exploitation of Beifort® can contribute to decrease the use of chemical fertilizers
Nickel-aluminium layered double hydroxide as an efficient adsorbent to selectively recover praseodymium and samarium from phosphogypsum leachate
No full textThis study aimed to synthesize a green powdered layered double hydroxide (LDH) based on nickel-aluminum (Ni–Al-LDH) to evaluate its efficiency in the removal of rare earth elements (REEs), Praseodymium (Pr3+) and Samarium (Sm3+), from synthetic effluents and real leachate using phosphogypsum as a secondary source of REEs. Several characterization techniques were employed to evaluate the physicochemical properties of Ni-Al-LDH adsorbent, such as specific surface area and porosity, functional surface groups and phases, and point of zero charge. The characterization results indicated that Ni-Al-LDH exhibited a typical layered structure confirming the successful synthesis. The effect of key adsorption variables, such as pH, contact time, initial concentration, and temperature, on the REEs adsorption was extensively studied in single-factor experiments separately. The kinetic and equilibrium adsorption data agreeably fitted the Avrami and Sips models, respectively. The maximum adsorption capacities for Pr3+ and Sm3+ adsorption were 18.13 and 15.68 mg g−1 at 298 K, respectively. The thermodynamic parameters (ΔH0, ΔS0, ΔG0) indicated that the adsorption was spontaneous, favorable, and exothermic for both Pr3+ and Sm3+. The interactions between Pr3+ and Sm3+ onto Ni-Al-LDH suggest that multiple adsorption mechanisms are involved, such as ion exchange, precipitation, chelation, and pore filling. Finally, the Ni-Al-LDH could selectively recover REEs, specially Pr3+ and Sm3+, from the real phosphogypsum leachate. It has been demonstrated that Ni-Al-LDH is a promising adsorbent material that could be used as an adsorbent for the recovery of REEs from synthetic and real effluents
Citrus fruit residues as alternative precursors to developing H2O and CO2 activated carbons and its application for Cu(II) adsorption
No full textDue to its toxicity, the presence of Cu(II) ions released in aquatic environments presents a serious threat to the environment and human health. In search of sustainable and low-cost alternatives, there are citrus fruit residues, which are generated in large quantities by the juice industries and can be used to produce activated carbons. Therefore, the physical route was investigated for producing activated carbons to reuse citrus wastes. In this work, eight activated carbons were developed, varying the precursor (orange peel-OP, mandarine peel-MP, rangpur lime peel-RLP, and sweet lime peel-SLP) and the activating agent (CO2 and H2O) to remove Cu(II) ions of the aqueous medium. Results revealed promising activated carbons with a micro-mesoporous structure, a specific surface area of around 400 m2 g–1, and a pore volume of around 0.25 cm3 g–1. In addition, Cu (II) adsorption was favored at pH 5.5. The kinetic study showed that the equilibrium was reached within 60 min removing about 80% of Cu(II) ions. The Sips model was the most suitable for the equilibrium data, providing maximum adsorption capacities (qmS) values of 69.69, 70.27, 88.04, 67.83 mg g–1 for activated carbons (AC-CO2) from OP, MP, RLP, and SLP, respectively. The thermodynamic behavior showed that the adsorption process of Cu(II) ions was spontaneous, favorable, and endothermic. It was suggested that the mechanism was controlled by surface complexation and Cu2+-π interaction. Desorption was possible with an HCl solution (0.5 mol L–1). From the results obtained in this work, it is possible to infer that citrus residues could be successfully converted into efficient adsorbents to remove Cu(II) ions from aqueous solutions
Implementation of information and communication technologies to increase sustainable productivity in freshwater finfish aquaculture – A review
No full textThe practice of continental aquaculture has grown globally, mainly due to its ability to provide protein to vulnerable populations and stimulate local economies in many regions of the world. In recent years, information and communication technologies (ICT) have been implemented to monitor, control, correct and even predict the behavior of critical parameters in fish farms to obtain sustainable productivity. A systematic literature review (SLR) was applied to identify the main variables contributing to the increase in sustainable productivity in freshwater aquaculture and the most used ICT tools to monitor or control these variables. It was found that aquaculture uses IoT and AI mainly on five fronts: water quality, fish feeding, water recirculation, fish transport and traceability, and fish welfare. The use of ICT tools in aquaculture has evolved from the use of simple sensors to the construction of predictive models using deep learning. However, it is worth highlighting the few articles that evaluate the impact of ICT tools on the productivity metrics of a freshwater fish farm under real conditions, and the information presented in the reviewed literature is difficult to compare due to the lack of uniformity in aquaculture projects where ICT tools are applied
Effectiveness and safety of dupilumab in adults with moderate and severe atopic dermatitis in Colombia: real-life experience
No full textBackground. Dupilumab is a treatment approved for uncontrolled moderate-to-severe atopic dermatitis (AD). Tropical and developing countries such as Colombia have characteristics that may impact the natural history of AD and access to medical treatments. In that sense, we aimed to describe the effectiveness and safety of dupilumab in adults with moderate to severe AD in a Colombian multicenter cohort. Methods.Multicenter descriptive study that included patients who started treatment between March 2018 and May 2020 in 6 centers. Disease severity was assessed using the following: Scoring Atopic Dermatitis (SCORAD), Eczema Area and Severity Index (EASI), Patient Oriented Eczema Measure (POEM), and Dermatology Life Quality Index (DLQI). These measurements were collected according to availability at baseline, 3–5 months, 6–12 months, and more than 12 months. Days of sick leave, hospitalizations, and AD flares before and after dupilumab treatment were reported. Adverse events (AEs) were recorded during follow-up. Results. Ninety-three patients were included, with a median age of 32 years (IQR: 24.0; 40.0) and a disease evolution time of 21 years (IQR: 16.0; 29.5). 88.2% had at least 1 allergic disease other than AD. An improvement greater than or equal to 75% EASI was observed in 41.7% of patients at 3–5 months, in 73.7% of patients at 6–12 months, and in 75.0% of patients after 12 months. For those reporting SCORAD and POEM, the median percent change ([IQR], n) from baseline in SCORAD was −67.1 ([−79.2; −54.2], n = 16), −70.5 ([−85.8; −47.9], n = 36) and −66.7 ([−77.3; −51.0], n = 13); and POEM, −58.6 ([−66.4; −55.5], n = 4), −73.0 ([−86.5; −66.7], n = 16) and −87.3 ([−93.4; −69.6], n = 8), respectively. Before initiation of dupilumab treatment, 82 (88.2%) patients reported at least 1 flare of AD in the past 12 months. During the follow-up period, 30 (32.3%) patients reported at least 1 exacerbation or flare. Twelve patients (12.9%) presented an AE and 3 (3.2%) patients discontinued dupilumab for this cause. Conclusions. Dupilumab was effective and safe for the treatment of moderate to severe AD in point-of-care settings, with results similar to randomized controlled and other real-life studies. These positive results are still maintained even though a high number of patients had short interruptions in the use of dupilumab due to administrative problems
Betting scenario for the management of university professional practices from the conformation of intersectoral cooperation networks
No full textThe professional practices represent a space for interorganizational and intersectoral alliances that contribute to the development of localities and regions. From this referent, the design and validation of intersectoral cooperation networks is considered pertinent for the effective management of professional practices. Therefore, this article is oriented towards the construction of the ideal scenario where a universitygovernmentcompany intersectoral cooperation network can operate on a horizon of 2030. Foresight is used as a research and planning method, in conjunction with the consultation of experts from different social sectors that lead to obtaining sixteen scenarios of probable occurrence. For this, techniques, such as the prospective workshop, Delphi method, structural analysis (MICMAC) and scenario analysis (SMIC), are used. The results show a bet scenario where the four finally selected events occur, with a probability of occurrence of 35.7%, which would allow establishing future strategies that allow the network to be operational. It is concluded that the formation of a cooperation network for the management of university professional practices represents in itself a strategy to strengthen the curriculum and guide the achievement of common objectives in the intersectoral context studied. The contribution of the article to the study of sustainability sciences stands out, since it addresses a theme that leads to the description, explanation and understanding of the sustainable development of localities and regions from an educational dimension. In this sense, the contribution is synthesized from three planes of reflection and analysis: firstly, the understanding of sustainability as a multidimensional construct, where education is a key dimension to consolidate sustainable development processes; secondly, the management of interorganizational and intersectoral networks as a cooperation strategy that promotes sustainable development; and thirdly, prospective as a planning method that leads to delineating betting scenarios for sustainability management from an educational perspective, more specifically from the university curriculum
Estrategias instruccionales para el fortalecimiento del rendimiento académico, en el marco del enfoque neuro sicoeducativo
No full textWithin the framework of formal educational systems, the profession of educators deserves a radical transformation, since the challenges imposed by the environment pose for this important educational actor the need to change the epistemological and methodological schemes that support their educational praxis. In this sense, the objective of the research was oriented to the analysis of the applications of the instructional strategies for the strengthening of the academic performance of the students of the educational institution of Bonda - District of Santa Marta-Colombia, within the framework of the neuropsychoeducational approachThe instructional strategies variable was supported by the contributions of Logatt (2015) and Valera Rincon and Rivero (2013) among others. Methodologically, the research is of an analytical type and is contextualized within the qualitative-quantitative approach; Its design is characterized as contemporary, punctual, non-experimental, transectional, descriptive and mixed (field and documentary simultaneously). This study takes place specifically in four (4) sites of the Bonda District Educational Institution (Main Site, Santana, Laureles and Masinga); which is a public educational establishment of the District of Santa Marta.In this research we can observe that although the teachers emphasize that the different types and models of instructional strategies are applied and that aspects and characteristics of the individuality of the students are taken into account, they do so moderately; which means a weakness to achieve the fundamental objectives of the neuropsychoeducational approach, as a modeling and information tool for students to live novel and pleasant learning experiences, which allow linking their emotions and thus contribute to the motivation to achieve meaningful learning.En el marco de los sistemas educativos formales, la profesión de los educadores amerita una transformación radical, pues los retos impuestos por el ambiente plantean para este importante actor educativo, la necesidad de cambiar los esquemas epistemológicos y metodológicos que sustentan su praxis educativa. En este sentido, el objetivo de la investigación estuvo orientado al análisis de las aplicaciones de las estrategias instruccionales para el fortalecimiento del rendimiento académico de los estudiantes de la institución educativa de Bonda - Distrito de Santa Marta-Colombia, en el marco del enfoque neuro sicoeducativo. La variable estrategias instruccionales, se sustentó con los aportes de Logatt (2015) y Valera Rincón y Rivero (2013) entre otros. Metodológicamente, la investigación es de tipo analítica y se contextualiza dentro del enfoque cualicuantitativo; su diseño se caracteriza como contemporáneo, de tipo puntual, no experimental, transeccional, descriptivo y mixto (de campo y documental simultáneamente). El presente estudio tiene lugar específicamente en cuatro (3) sedes de la Institución Educativa Distrital de Bonda (Sede Principal, Santana y Laureles); la cual es un establecimiento educativo público del Distrito de Santa Marta. En esta investigación podemos observar que aunque los profesores enfatizan en que sí se aplican los diferentes tipos y modelos de estrategias instruccionales y se toman en cuenta aspectos y características propias de la individualidad de los estudiantes lo realizan moderadamente; lo cual significa una debilidad para alcanzar los objetivos fundamentales del enfoque neuro sicoeducativo, como herramienta de modelaje e información para que los estudiantes vivencien experiencias de aprendizaje novedosas y placenteras, que permitan vincular sus emociones y de esa forma contribuir con la motivación para alcanzar un aprendizaje significativo.INTRODUCCIÓN 12 --
CAPÍTULO I 167 --
PLANTEAMIENTO DEL PROBLEMA 17 --
PREGUNTA PROBLEMA 29 --
OBJETIVOS DE INVESTIGACION 29 --
OBJETIVO GENERAL 29 --
OBJETIVOS ESPECÍFICOS 29 --
JUSTIFICACIÓN 30 --
DELIMITACIÓN Y ALCANCE 36 --
DELIMITACIÓN TEMÁTICA 36 --
DELIMITACIÓN ESPACIAL 37 --
ELIMITACIÓN TEMPORAL 38 --
CAPÍTULO II 39 --
ANTECEDENTES 39 --
ESTRATEGIAS INSTRUCCIONALES 53 --
TIPOS DE ESTRATEGIAS INSTRUCIONALES 60 --
ESTRATEGIAS DE ENSEÑANZA PREINSTRUCCIONALES 60 --
ESTRATEGIAS DE ENSEÑANZA COINSTRUCCIONALES 62 --
ESTRATEGIAS DE ENSEÑANZA POSINSTRUCCIONALES 63 --
METODOS PARA LA FORMACION ESTRATEGICA INSTRUCCIONALES 64 --
MODELADO 65 --
INFORMACIÓN 66 --
CRITERIOS PARA LA APLICACIÓN DE LAS ESTRATEGIAS INSTRUCCIONALES 68 --
CARACTERISTICAS BIOPSICOSOCIALES DE LOS ESTUDIANTES 69 --
EL TIEMPO, EL AMBIENTE NATURAL Y SOCIAL 69 --
TAMAÑO DEL GRUPO 70 --
EL ENFOQUE NEURO SICOEDUCATIVO COMO CRITERIO DE ANÁLISIS 71 --
PRINCIPIOS DEL APRENDIZAJE BAJO EL ENFOQUE NEURO SICOEDUCATIVO 76 --
APLICACIÓN DE ESTRATEGIAS INSTRUCCIONALES BAJO EL ENFOQUE NEURO SICOEDUCATIVO 93 --
MARCO LEGAL 95 --
MARCO CONCEPTUAL 98 --
OPERACIONALIZACION DE LAS VARIABLES 102 --
TABLA DE OPERACIONALIZACIÓN DE VARIABLE 103 --
CAPÍTULO III 105 --
SISTEMA METODOLÓGICO 105 --
ENFOQUE EPISTEMOLÓGICO DEL ESTUDIO 105 --
TIPO DE INVESTIGACIÓN 107 --
DISEÑO DE LA INVESTIGACIÓN 109 --
POBLACIÓN DE ESTUDIO Y FUENTES DE INFORMACIÓN 109 --
TÉCNICAS DE RECOLECCIÓN DE DATOS 111 --
VALIDEZ Y CONFIABILIDAD DEL CUESTIONARIO 113 --
TÉCNICS DEL ANÁLISIS DE RESULTADO 115 --
CAPITULO IV 118 --
RESULTADO DEL ESTUDIO 118 --
DISCUSION DE RESULTADOS 131 --
CONCLUSIONES 135
RECOMENDACIONES 142 --
REFERENCIAS 148 -
ANEXOS 152--Magíster en EducaciónMaestrí
Release kinetics of multi-nutrients from volcanic rock mining by-products: Evidences for their use as a soil remineralizer
No full textGreat quantities of stone by-products are stored alongside different exploiting mines in south Brazil, which are becoming an unsustainable environmental issue. Powder materials of andesite and dacite rocks were obtained from two mining companies of Southern Brazil. The particle size classification of the materials was determined by sieving. The X-ray diffraction (XRD) technique was used to identify the mineral phases of the by-products and X-ray fluorescence (XRF) was applied to determine their chemical compositions. The concentrations of calcium (Ca), potassium (K), magnesium (Mg), phosphorus (P) and silicon (Si) released by the by-products were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Dissolution rates of andesite and dacite rocks were measured in Milli-Q water, and in solutions of 0.1 mol L−1 citric acid, and Milli-Q water acidified with 0.5 mol L−1 acetic acid, as a function of reaction times at 24–96 h (short-term), and at 96–5760 h (long-term). The solutions were agitated continuously on a mechanical rotatory shaker at room temperature. The parabolic diffusion, simplified Elovich, and power function models were applied at both time slots of solid-solution reaction. The results indicated that the relationships of quantity of released multi-nutrients were well described by power equation: ln qt = ln a + b ln t. Dissolution rates were obtained based on the release of Ca, K, Mg, P and Si at a steady state under far from equilibrium conditions. Dissolution rates of both by-products were not affected, within the experimental uncertainty, by Milli-Q water. Although the by-products dissolution rates were unaffected by Milli-Q water, its rates are increased along the time. The dissolution of the by-products minerals was significantly affected by the pH of the solutions. The multi-elements release by both by-products in 0.1 mol L−1 citric acid solution was significantly larger than another solutions, indicating that exchangeable cations were readily available in citric acid solution. The results obtained from power function model in two reaction time intervals can contribute to estimate the multi-nutrients-supplying power of by-products to soil. The present study provides both to solving an environmental issue associated with Brazilian rock exploitation and to create an alternative for soil fertilization and a more sustainable agriculture.Gómez Plata, leandro-will be generated-orcid-0000-0002-2944-4479-600Gindri Ramos, Claudete-will be generated-orcid-0000-0003-2172-8052-600Silva Oliveira, Marcos LeandroSilva O., Luis F
Combined use of the extended theory of connections and the onto‑semiotic approach to analyze mathematical connections by relating the graphs of f and f
No full textThe literature reports that students have difficulties connecting different meanings, multiple representations of the derivative, and performing reversibility processes between representations of f and f’. The research goal is to analyze the mathematical connections that university students establish when solving tasks that involve the graphs of f and f’ when the two functions do not have associated symbolic expressions. Seven students from the first year of undergraduate studies in mathematics from a university in southern Mexico participated. For data collection, two tasks involving the graphical context of the derivative were applied. An analysis of the mathematical activity was carried out by the participants with the analysis model proposed by the onto-semiotic approach, and thematic analysis with types of mathematical connections from the extended theory of connections was carried out to infer the connections made in that mathematical activity, which allowed us to consider the reversibility connection between the graphs of f and f’ as the encapsulation of a portion of the mathematical activity. Four students establish the reversibility relationship between the graph of f and the graph of f’. It has been concluded that some students can establish the reversibility connection between the graphs of f and f’, but the complexity of the mathematical activity that encapsulates the connection explains (by showing everything that the student must do) why some students are not able to establish it
Direct medical costs of diabetes mellitus in Colombia
No full textObjectives. Diabetes mellitus type 2 (DM2) is a public health issue worldwide. In this study we estimated the health care resource utilization and the annual direct medical costs of diabetes mellitus in Colombia, 2018-2021
Methods. Cross-sectional study of patients with DM2 of Mutual SER EPS, a poor population insurance company with 2.5 million insured. We analyzed the annually health care resource utilization (HCRU) of patients who consumed health services and their direct medical costs. Absolute and relative frequencies were estimated to describe HCRU, and costs were expressed in averages with 95% confidence intervals (95%CI). This study was conducted from the health system perspective. Costs were reported in American dollars using an exchange rate of 1USD = 3,981.16 COP.
Results. We analyzed 2,788 DM2 patients, 68.8% male. The average of age and body mass index was 60.7 years old (SD. 13.6) and 26.4 (SD. 5.3). The annual average direct medical cost of a DM2 patient that used health services was US224.4 (95%CI 220.2-238.6); 1,304 (46.7%) used specialist consultation, with average direct costs of US69.2 (95%CI 56.7-81.7), among other services. Conclusions. DM2 represents a high economic burden for this insurance company, as a prevalent disease in Colombia. Drugs, consults by specialists, labs. & Images were the most used services for these patients. This study provides inputs to conduct cost-effectiveness analysis of health technologies for DM2