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DIN 16MnCr5 is commonly used in mechanical engineering contact applications such as gears, joint parts, shafts, gear wheels, camshafts, bolts, pins, and cardan joints, among others. This study examined the microstructural and mechanical properties and tribological behavior of different surface treatments applied to DIN 16MnCr5 steel. The samples were hardened at 870 °C for 15 min and then quenched in water. The surface conditions evaluated were as follows: quenched and tempered DIN 16MnCr5 steel samples without surface treatments (control group), quenched and tempered DIN 16MnCr5 steel samples with gas-nitriding at 560 °C for 6 h, quenched and tempered DIN 16MnCr5 steel samples with pack boriding at 950 °C for 4 h, and quenched and tempered DIN 16MnCr5 steel samples with duplex gas-nitriding and pack boriding. Microstructure characterization was carried out using metallographic techniques, optical microscopy, scanning electron microscopy with energy-dispersive spectroscopy, and X-ray diffraction. The mechanical properties were assessed through microhardness and elastic modulus tests using nanoindentation. The tribological behavior was evaluated using pin-on-disc tests following the ASTM G99-17 standard procedure under dry sliding conditions. The results indicated that the surface treated with duplex gas-nitriding and pack boriding exhibited the highest wear resistance and a reduced coefficient of friction due to improved mechanical properties, leading to increased hardness and elastic modulus.

The 17-4 PH stainless steel is widely used in the aerospace, petrochemical, chemical, food, and general metallurgical industries. The present study was conducted to analyze the mechanical properties of two types of 17-4 PH stainless steel—commercial cold-rolled and direct metal laser sintering (DMLS) manufactured. This study employed linear and nonlinear tensile FEM simulations, combined with various materials characterization techniques such as tensile testing and nanoindentation. Moreover, microstructural analysis was performed using metallographic techniques, optical microscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The results on the microstructure for 17-4 PH DMLS stainless steel reveal the layers of melting due to the laser process characterized by complex directional columnar structures parallel to the DMLS build direction. The mechanical properties obtained from the simple tension test decreased by 17% for the elastic modulus, 7.8% for the yield strength, and 7% for the ultimate strength for 17-4 PH DMLS compared with rolled 17-4 PH stainless steel. The FEM simulation using the experimental tension test data revealed that the 17-4 PH DMLS stainless steel experienced a decrease in the yield strength of ~8% and in the ultimate strength of ~11%. A reduction of the yield strength of the material was obtained as the grain size increased.

This study evaluates the tribological performance of nanolubricants of a vegetable oil (sunflower oil) reinforced with different concentrations of environmentally-friendly nanoparticles of halloysite clay nanotubes (HNTs). Tribological characterization was performed under different conditions to determine its effect on the nanolubricants’ performance and optimal HNT concentration. The tribological performances under low and high contact pressures were analyzed with a block-on-ring tribometer following the ASTM G-077-05 standard procedure. The extreme pressure (EP) properties of the nanolubricants were determined with a T-02 four-ball tribotester according to the ITeE-PIB Polish method for testing lubricants under scuffing conditions. In addition, the lubrication performance of the newly-developed vegetable oil-based nanolubricants was evaluated in an industrial-type application through a tapping torque test. The results indicated that at a low contact pressure 1.5 wt.% HNTs/sunflower oil provided the best tribological behavior by decreasing the coefficient of friction (COF) and wear volume loss by 29 and 70%, respectively. For high contact pressures, 0.05 wt.% HNTs lowered COF and wear by 55% and 56%, respectively. The load-carrying capacity increased by 141% with 0.10 wt.% HNTs compared to the sunflower oil. A high tapping torque efficiency was obtained with HNTs that can prolong tool life in the machining process. Therefore, this study suggests that HNTs/sunflower oil could be used as green lubricants for industrial applications.

In the present research project, a novel portable battery-powered handheld device able to produce micron and submicron fibers using centrifugal forces is proposed. The design includes spinnerets with a clamshell configuration with multiple chambers or reservoirs (2, 4, and 8) and different exit orifice diameters (400, 500, 600, and 800 µm). The rotational speed is controlled via an Arduino microcontroller. To validate the design, a series of experiments were conducted and the effect of the orifice diameter, number of chambers, and velocity on the resulting fibers’ diameter and yield was studied. For the experiments, a polymeric solution of Polyvinyl Alcohol (PVA) was prepared. The fiber yield was gravimetrically quantified, and the fiber morphology and diameter were analyzed by means of scanning electron microscopy (SEM). The experimental results showed that spinnerets with an orifice diameter of 500 microns yielded the greatest amount of fibers (0.0777 g). In addition, the number of chambers also affected the amount of fibers produced, and it was determined that the fiber diameter size is dependent on the spinneret speed. Fibers 80 nm in diameter were observed at 6500 rpm.

In recent years, there has been growing concern regarding the use of petroleum-based lubricants. This concern has generated interest in readily biodegradable fluids such as vegetable oils. The present work evaluated the rheological and tribological characteristics of sunflower oil modified with silicon dioxide (SiO2) and titanium dioxide (TiO2) nanoparticles as lubricant additives at different concentrations. A parallel plate rheometer was used to evaluate the effects of concentration and shear rate on the shear viscosity, and the experimental data was compared with conventional models. The wear protection and friction characteristics of the oil-formulations were evaluated by conducting block-on-ring sliding tests. Surface analysis-based instruments, including scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and profilometry, were used to characterize the morphology and structure of the worn surfaces. The experimental results showed that the coefficient of friction decreased with the addition of SiO2 and TiO2 nanoparticles by 77.7% and 93.7%, respectively when compared to base sunflower oil. Furthermore, the volume loss was lowered by 74.1% and 70.1%, with the addition of SiO2 and TiO2 nanoparticles, respectively. Based on the experimental results, the authors conclude that modified sunflower oil enhanced with nanoparticles has the potential for use as a good biodegradable lubricant.

A modular torque measuring instrument capable of performing tapping torque tests (TTT) according to the ASTM D-5619 standard was designed, developed, and validated. With this new instrument, the performance of different lubricants can be evaluated in terms of frictional torque and energy consumption during tapping processes. This instrument can adapt onto any conventional milling machine or CNC machine and operate under various machining operations such as tapping, drilling, and other processes. To validate the design and performance of this new device, three commercially available lubricants were evaluated. From the three tested conditions, the results showed good repeatability, with consistent results throughout the different tests for each lubricant. The impact of such a proposed instrument ranges from academic use to industrial business use.

In metal-forming processes, the use of lubricants for providing desirable tribological conditions at the tool−workpiece interface is critical to increase the material formability and prolonging tool life. Nowadays, the depletion of crude oil reserves in the world and the global concern in protecting the environment from contamination have renewed interest in developing environmentally-friendly lubricants derived from alternative sources such as vegetable oils. In the present study, the rheological and tribological behavior of coconut oil modified with nanoparticle additives was experimentally evaluated. Two different nanoparticle additives were investigated: Silicon dioxide (SiO2) and copper oxide (CuO). For the two conditions, nanoparticles were dispersed at different concentrations within the coconut oil. The effects of concentration and shear rate on the viscosity were evaluated and the experimental data was compared with conventional models. A custom-made tribotester was used to evaluate the effect of concentration on the tribological performance of the nano-lubricants. The experimental results showed that wear volume loss was lowered by 37% and 33% using SiO2 and CuO nanoparticles, respectively. Furthermore, the addition of SiO2 and CuO nanoparticles decreased the coefficient of friction (COF) by 93.75% and 93.25%, respectively, as compared to coconut oil without nanoparticles.

One of the main causes of hip prostheses failure is the premature wear of their components. Multi-directional motion or “cross-shear” motion has been identified as one of the most significant factors affecting the wear rate of UHMWPE in total hip joint replacement prostheses. To better evaluate the effect of this cross-shear motion on the tribological behavior of different biomaterials, a new wear testing device has been designed and developed. This new instrument is capable to reproduce the “cross-shear” effect with bidirectional motion on bearing materials and to determine coefficient of friction (COF) between surfaces during testing. To validate the functionality of this new testing platform, alumina balls were articulated against Ti-6Al-4V ELI alloy disks in Ringer’s solution. Four different articulation patterns, all with identical path lengths per cycle, were tested. Gravimetric weight loss was converted to volumetric wear data in order to determine the effects of motion patterns on the wear. Worn surfaces were analyzed by scanning electron microscopy. This scientific approach to quantifying the tribological effects of cross-shear provides fundamental data that are crucial in evaluating potential biomaterials for use in knee and hip joint replacements.

Background: Increasing evidence supports the united airway disease concept for the management of upper and lower respiratory tract diseases, particularly in patients with asthma and chronic rhinosinusitis with nasal polyps (CRSwNP). However, evidence for a combined approach in asthma and CRSwNP is scarce. Objective: In this systematic review, we focused on the role of biologics in the lung function and quality of life in patients with severe asthma and CRSwNP. Methods: We conducted a systematic search of 3 electronic databases using 2 search strategies to identify studies published from January 2010 to March 2022. Quality assessment was performed with the Critical Appraisal Skills Programme. Results: Of 1030 studies identified, 48 original studies reporting data of benralizumab (12), dupilumab (14), mepolizumab (10), omalizumab (13), and reslizumab (2) were analyzed. Primary diagnosis was mostly asthma or CRSwNP, with only 15 studies, mainly observational, performed in populations with united airway disease. In total, 18 studies reported data on quality of life (mostly 22-item Sino-Nasal Outcome Test score), 8 on lung function (mostly FEV1), and 22 on both outcomes. Significant FEV1 and 22-item Sino-Nasal Outcome Test score improvements were consistently observed after 24-week treatment, and thereafter, mostly in real-world studies that included variable proportions of patients with asthma/CRSwNP. Conclusions: The use of biologics in patients with severe asthma and CRSwNP was overall associated with significant improvements in lung function and quality of life. However, we observed a high heterogeneity of populations and outcome measurements across studies. Notwithstanding the need of larger studies, our results reinforce the joint management of asthma and CRSwNP as united airway disease in clinical practice.

Abstract Background Scientific evidence on patients with multimorbid type 2 asthma and chronic rhinosinusitis with nasal polyps (CRSwNP) from a united airways disease (UAD) perspective remains scarce, despite the frequent coexistence of these entities. We aimed to generate expert consensus-based recommendations for the management of UAD patients. Methods Using a two-round Delphi method, Spanish expert allergists, pulmonologists and otolaryngologists expressed their agreement on 32 statements (52 items) on a 9-point Likert scale, classified as appropriate (median 7–9), uncertain (4–6) or inappropriate (1–3). Consensus was considered when at least two-thirds of the panel scored within the range containing the median. Results A panel of 30 experts reached consensus on the appropriateness of 43 out of the 52 (82.7%) items. The usefulness of certain biomarkers (tissue and peripheral blood eosinophil count, serum total IgE, and fraction of exhaled nitric oxide [FeNO]) in the identification and follow-up of type 2 inflammation, and assessment of the response to biologics, were agreed. Some of these biomarkers were also associated with disease severity and/or recurrence after endoscopic sinus surgery (ESS). Consensus was achieved on treatment strategies related to the prescription of anti-IL-4/IL-13 or anti-IgE agents, concomitant treatment with systemic corticosteroids, and combining or switching to biologics with a different mechanism of action, considering a number of UAD clinical scenarios. Conclusion We provide expert-based recommendations to assist in clinical decision-making for the management of patients with multimorbid type 2 asthma and CRSwNP. Specific clinical trials and real-world studies focusing on the single-entity UAD are required to address controversial items.

Resumen: El asma grave afecta del 3 al 10% de la población mundial, según estimaciones de la Iniciativa Global para el ASMA (GINA). El asma alérgica es uno de los fenotipos más comunes del asma grave y se caracteriza por una inflamación de tipo 2 provocada por alérgenos y en el que la inmunoglobulina E (IgE) es una mediadora clave, lo que la ha convertido en una diana terapéutica importante. La introducción de las terapias o de los tratamientos biológicos dirigidos ha supuesto la entrada del manejo del asma grave en la era de la medicina de precisión y que el objetivo del tratamiento aspirase a la remisión clínica de la enfermedad. Existe un porcentaje importante de pacientes con asma alérgica grave que no responden a los tratamientos y cuyos síntomas no están controlados. En este documento, un grupo de expertos en el manejo del asma alérgica grave ha revisado y evaluado la evidencia más relevante relativa a la fisiopatología y a los fenotipos del asma grave alérgica, la función de la IgE en la inflamación alérgica, la identificación de alérgenos, las técnicas, biomarcadores y retos diagnósticos y los tratamientos y estrategias disponibles para el manejo de la enfermedad, con un especial foco en los tratamientos biológicos. A partir de esta revisión se han desarrollado unas recomendaciones que han sido validadas a través de un proceso de consenso Delphi con el objetivo de ofrecer mejoras en el manejo del asma alérgica grave a los profesionales implicados e identificar las necesidades no cubiertas en el manejo de esta patología. Abstract: Severe asthma affects 3%-10% of the world's population, according to estimates by the Global Initiative for ASTHMA (GINA). Allergic asthma is one of the most common phenotypes of severe asthma and it is characterized by allergen-induced type 2 inflammation in which immunoglobulin E (IgE) is a key mediator, making it an important therapeutic target. The introduction of targeted biological therapies or treatments has entered the management for severe asthma in the era of precision medicine, and the goal of treatment is clinical remission of the disease. There is a significant percentage of patients with severe allergic asthma who do not respond to treatments and whose symptoms are not controlled. In this paper, a group of experts in the management of severe allergic asthma reviewed and evaluated the most relevant evidence regarding the pathophysiology and phenotypes of severe allergic asthma, the role of IgE in allergic inflammation, allergen identification, techniques, biomarkers and diagnostic challenges, available treatments and strategies for disease management, with a special focus on biological treatments. From this review, recommendations were developed and validated through a Delphi consensus process with the aim of offering improvements in the management of severe allergic asthma to the professionals involved and identifying the unmet needs in the management of this pathology.

Background and aimsMany improvements have been made in the treatment of human immunodeficiency virus (HIV) in pediatric patients; however, challenges remain in terms of achieving normal growth, body composition, and metabolism during treatment, etc. Current nutritional recommendations are based on studies performed in adults, with limited data on the HIV-infected pediatric population. Therefore, this study aimed to compare the resting energy expenditure (REE) of asymptomatic HIV-infected pediatric patients with healthy counterparts and to compare body composition, dietary intake, and physical activity between the two groups.MethodsThis was a cross-sectional study of asymptomatic HIV-infected children who were receiving antiretroviral therapy; the infected group was compared with the uninfected group, matched by age (± 6 months), sex, and body mass index (± 0.5 z-score). Participants were recruited between 2021 and 2022, as outpatients. In both groups, REE was determined by indirect calorimetry and body composition by bioelectrical impedance analysis and hand strength, measured using a hydraulic hand dynamometer.ResultsSeventy-eight participants were enrolled, where n = 39 HIV-infected children and n = 39 controls, with a mean age of 11.6 ± 3.4 years old. REE was significantly higher in the HIV group (1254.4 ± 334.7 kcal/day vs. 1124.7 ± 321 kcal/day, p = 0.013) than in the control group. Fat-free mass (FFM) was lower in the HIV group (28.2 ± 10.5 kg vs. 32 ± 11.2 kg, p = 0.001); this trend continued when the index skeletal muscle was evaluated (7.2 ± 1.2 vs. 7.6 ± 1.5, p = 0.04). The strength of the dominant hand was also lower in the HIV group (12 (8–18) kg vs. 20 (10.5–26) kg, p < 0.0001).ConclusionsChildren with asymptomatic HIV infection have higher REE than their uninfected peers. They also present decreased FFM, skeletal muscle mass index, and muscle strength. These parameters should be considered during nutritional assessment in this population to have a favorable impact on nutritional status and growth.

INTRODUCCIÓN. El tema de la dimensión emocional en el campo educativo se vincula necesariamente con procesos motivacionales y de aprendizaje. En esta investigación se focaliza la atención hacia a aquellas emociones de orden epistémico asociadas con objetivos de aprendizaje concretos, en este caso aprender a enseñar a argumentar en ciencias. En este sentido, la investigación propone como objetivo central conocer las emociones epistémicas que manifiestan los futuros educadores al asumir el reto de aprender a enseñar a argumentar en clase de ciencias, antes y después de cursar una actividad académica en una universidad pública colombiana. MÉTODO. Para dar respuesta al objetivo propuesto, se diseñó un estudio fundamentado en la investigación-acción y para el análisis de la información se combinó acciones de carácter descriptivo-comprensivo. Los participantes fueron 57 estudiantes inscritos en una actividad académica perteneciente a la malla curricular de un programa de formación de docentes. RESULTADOS. Se destaca la presencia de emociones epistémicas como la curiosidad y disfrute, importantes para activar estrategias profundas para el procesamiento de información. También la identificación de la ansiedad, vinculada con dispositivos activadores como la valoración de logro y control de la actividad. CONCLUSIONES. Promover acciones reflexivas sobre las emociones epistémicas, aporta y enriquece no solo la comprensión de la relación emociones y objetivos epistémicos, sino también la reducción gradual de emociones negativas como la ansiedad y, por consiguiente, el fortalecimiento de emociones positivas como el disfrute y la curiosidad, vinculadas precisamente con la motivación de lograr aprendizajes profundos.

El Código Orgánico General de Procesos, ha instaurado el procedimiento monitorio a través del cual los propietarios de deudas determinadas, líquidas, exigibles y de plazo vencida que no consten en un título ejecutivo y que no excedan de los cincuenta salarios básicos unificados (SBU) del trabajador, puedan ejercer su derecho de cobro, garantizando que este procedimiento sea célere y efectivo, contribuyendo así a descongestionar los procesos de administración de justicia. Este procedimiento incluye el patrocinio de un abogado, con una limitante: si el salario es inferior a los tres salarios básicos unificados (SBU) no se requiere este patrocinio; lo cual contraría lo dispuesto en la Constitución que expresa que todo trámite judicial requiere el patrocinio de un abogado, además en la práctica los casos presentan una oposición a la demanda lo cual conlleva a una audiencia única, para lo cual las partes requieren para su defensa de un abogado, a quien también se le limita el derecho al trabajo. Frente a esta situación se aborda la importancia de que el patrocinio de un abogado sea un requisito obligatorio independientemente de la cuantía de la obligación.

Background: Football practice involves a great muscular demand, leading to the development of the lower limbs that, on occasions, can cause deviations from the normal anthropometric values. The quadriceps angle (Q angle) is a value often taken as a reference for the alignment of the lower limbs. Objective: To observe the changes of the Q angle in young football players, because of muscular effort, analyzing the differences between four groups of different ages and to determine whether the playing position might influence these variations. Methods: A cross sectional study was carried out with 104 male subjects divided into four groups according to age: under 8 years-old, 8-17 years-old, 17-21 years-old and over 21 years-old. A photograph was taken in standing position and the Q angle was plotted with KINOVEA® software. As for the reliability of the measurements, intraclass intra and interobserver coefficient were 0.958 and 0.860 respectively. The study was conducted in mid-season. Results: Q angle value is greater in those under 8 years of age and decreases gradually and significantly (p 0.005), except for goalkeepers, who suffered a difference in the evolution of the angle within their age category (p 0.8) except forward (value

El presente trabajo analiza la actuación del Consejo de la Judicatura del Ecuador como órgano administrativo al aplicar la sanción disciplinaria del error inexcusable, cuya decisión trae consigo la destitución de los Jueces; el problema tiene relación con el procedimiento que se aplica en este tipo de sumarios, ya que la declaración de dicha figura sancionatoria debe ser advertida dentro de la misma vía jurisdiccional por los mismos Jueces que conocen las causas ordinarias y constitucionales vía recursos, conforme lo establece el Art. 131.3 del Código Orgánico de la Función Judicial y no como lo podría haber realizado dicho organismo vulnerando el debido proceso y la misma independencia Judicial consagrada en el Art. 76.3 y 168 de la Constitución del Ecuador respectivamente; incluso la Corte IDH ha hecho referencia a esta cuestión en su jurisprudencia, a la que Ecuador se encuentra adherido.

En las últimas dos décadas se ha focalizado en la escuela, el interés sobre la argumentación como herramienta importante para el desarrollo del pensamiento crítico. Actualmente, se pueden encontrar diferentes modelos de argumentación propuestos por diversos autores. A pesar de ser bastantes, lo cierto es que no parece haber un norte claro que permita orientar y seleccionar los modelos según su necesidad o conveniencia a la hora de aplicarlos en el aula. Por ello, en el presente artículo se exponen los resultados de una investigación analítica comparativa de cada uno de los principales modelos argumentativos y sus precursores: Aristóteles (1982, 1988), Gótama (1913; la escuela nyāya o lógica india), Sócrates (Platón, 2010, Crát.), Sexto Empírico (1996), los filósofos vitandines (argumentación negativa india), la escuela de los lógicos (shi), la escuela china de los nombres, Toulmin (2007), De Zubiría (2001) y De Zubiría (2006), Díaz (2014), Adam (1992), Van Dijk (1996a, 1996b), Van Eemeren (2019), Van Eemeren y Grootendorst (2002), Perelman (2007) y Perelman y Olbrechts-Tyteca (1989). Dicho análisis permitió clasificar todos estos modelos en cuatro tipos (formal, conceptual, persuasivo y pragmadialéctico) a partir de sus elementos y estructura. Una vez realizado este análisis, se evalúa la aplicabilidad de cada uno de ellos en los procesos de enseñanza a la luz de los siguientes criterios: aportes a la construcción del conocimiento; habilidades comunicativas intervinientes; procesos de pensamiento favorecidos; actitudes, valores y emociones que permite desarrollar; limitaciones de cada modelo; y tipo de población para los que son más pertinentes. En síntesis, se pretende ofrecer herramientas que faciliten a maestros e investigadores reconocer los principales modelos argumentativos existentes, sus características, posibles bondades y los alcances de su puesta en práctica en el salón de clase.

Introduction: Adding LAMA to LABA/ICS is recommended to improve control in patients with persistent asthma. Methods: This observational, retrospective, before-and-after study considered patients diagnosed with asthma who started LABA/ICS + LAMA treatment (triple therapy, TT) between 1 January 2017 and 31 December 2018 and had been treated with LABA/ICS (dual therapy, DT) in the year before. Changes in lung function and exacerbation rates, healthcare resource utilization, and healthcare and non-healthcare costs (€2019) were estimated in patients with asthma in clinical practices in Spain. Data from computerized medical records from seven Spanish regions were collected ±1 year of LAMA addition. Results: 4740 patients (64.1 years old [SD: 16.3]) were included. TT reduced the incidence of exacerbations by 16.7% (p < 0.044) and the number of patients with exacerbations by 8.5% (p < 0.001) compared to previous DT. The rate of patients with severe exacerbations requiring systemic corticosteroids and their hospitalization rates significantly decreased by 22.5% and 29.5%. TT significantly improved FEV1, FVC, and FEV1/FVC, saving €571/patient for society. Younger patients with asthma (18–44 years old) and patients with severe asthma (FEV1 < 60%) performed better upon the initiation of TT. Conclusions: TT reduced asthma exacerbations, improved lung function and reduced healthcare costs vs. DT, particularly in patients requiring systemic corticosteroids to treat severe exacerbations.

Dietary nutrient composition is essential for shaping important fitness traits and behaviours. Many organisms are protein limited, and for Drosophila melanogaster this limitation manifests at the level of the single most limiting essential Amino Acid (AA) in the diet. The identity of this AA and its effects on female fecundity is readily predictable by a procedure called exome matching in which the sum of AAs encoded by a consumer's exome is used to predict the relative proportion of AAs required in its diet. However, the exome matching calculation does not weight AA contributions to the overall profile by protein size or expression. Here, we update the exome matching calculation to include these weightings. Surprisingly, although nearly half of the transcriptome is differentially expressed when comparing male and female flies, we found that creating transcriptome-weighted exome matched diets for each sex did not enhance their fecundity over that supported by exome matching alone. These data indicate that while organisms may require different amounts of dietary protein across conditions, the relative proportion of the constituent AAs remains constant. Interestingly, we also found that exome matched AA profiles are generally conserved across taxa and that the composition of these profiles might be explained by energetic and elemental limitations on microbial AA synthesis. Thus, it appears that ecological constraints amongst autotrophs shape the relative proportion of AAs that are available across trophic levels and that this constrains biomass composition.

Los objetivos del presente artículo de investigación son caracterizar modelos de explicación sociocientífica sobre cambio climático y establecer los tipos de relaciones multimodales (cooperación y especialización) entre los lenguajes utilizados por estudiantes de 13-15 años. La investigación es de tipo cualitativo con un alcance comprensivo, modalidad estudio de caso, que analiza el contenido de tres modos de lenguaje (oral, escrito y gráfico) empleados por los estudiantes de una institución educativa colombiana durante su participación en escenarios de discusión y debate sobre un problema sociocientífico. Se presentan los resultados de dos modelos analizados en profundidad. El análisis permite identificar que los estudiantes centran su debate en las causas antropogénicas y naturales que han sido expuestas por los expertos. Las diferencias entre los modelos identifican mayor contenido científico (ecológico-ambiental) o social (político, ético y económico) de diferente naturaleza, así como mayor profundidad conceptual en las relaciones intersemióticas de especialización, que de cooperación.

Fundamento: La pandemia por el coronavirus SARS-CoV-2, genera afectaciones en las esferas social, económica y sanitaria de un país, y de manera particular, consecuencias psicológicas negativas en el personal sanitario de hospitales públicos, considerados como la primera línea de atención a pacientes con esta enfermedad. Objetivo: Describir factores asociados a la presencia de malestar psicológico en el personal sanitario de un hospital general público en Ecuador, durante la pandemia de COVID-19. Metodología: Estudio no experimental, de corte transversal, con alcance descriptivo-correlacional. Los datos correspondieron a 276 funcionarios de la salud que respondieron un instrumento online, con un módulo de datos sociodemográficos y una escala de tamizaje de malestar psicológico, estos se aplicaron después de una intervención en salud dirigida al personal de salud realizada al inicio de la pandemia, en mayo del año 2020. Se realizaron análisis descriptivos y de asociación, mediante el software SPSS 25.0. Resultados: La muestra estuvo compuesta por 76.1 % de mujeres, 23.9 % de hombres, con una media de edad de 36 años, en mayor cantidad con profesionales de Enfermería (33.7 %), seguido de Medicina (24.3 %). El 70.7 % del personal de salud presentó malestar psicológico, de estos, el 26.1 % con indicativo de trastorno mental. Se encontraron tres variables asociadas a la presencia de malestar psicológico: clima laboral, teletrabajo y convivir con grupos de riesgo. Conclusiones: El personal de Salud ha presentado afectación en su salud mental asociado a las condiciones sociolaborales durante la pandemia.

Superatom molecular orbitals (SAMOs) are atom-like molecular orbitals that have been observed in the buckminsterfullerene C60 molecule. We studied the ice-like water cluster (H2O)10 that is expected to be ubiquitous in nature in nanoscale microenvironments at ambient temperatures due to the nanoconfinement effect. We report for the first time the theoretical prediction of the existence of SAMOs in the adamantanoid nanostructured water cluster (H2O)10. The geometry of the adamantanoid water cluster (H2O)10 was optimized using the Restricted Hartree-Fock method and the ab-initio second-order Møller-Plesset perturbation theory (MP2) method, as well as the aqueous solvent phase polarizable continuum method (PCM). The optimized (H2O)10 structure is a distorted adamantanoid that closely matches the crystal structure of (H2O)10 that was previously reported. The theoretical studies using Hartree-Fock (HF), MP2, or Density Functional Theory (DFT) predict that the adamantanoid water cluster (H2O)10 exhibits SAMOs in the low-lying LUMOs. The orbital energies calculated with these methods are reported. The lowest-lying SAMOs in the water cluster (H2O)10 is the most intriguing SAMO due to its s-orbital character and potential to delocalize electrons in a large area that surrounds the cluster. The electron affinity of the water cluster (H2O)10 was calculated using HF, MP2, and DFT methods and the values obtained from each method were (kJ/mol) +74.71, -770.58, and -48.57, respectively. The existence of SAMOs in low-lying LUMO levels indicate of possible supramolecular chemistry of the water clusters with interfacial implications in nanoconfined spaces. Overall, these theoretical results predict new fundamental properties of water clusters that may have deep implications and impact in biological and nanotechnology systems that involve nanostructured water in confined spaces.

Objective: To collect perspectives and explore consensus for expert recommendations related to asthma control and the use of telemedicine among professionals who manage patients with asthma. Design: A Delphi-like questionnaire was designed to analyse the level of agreement about several recommendations formulated by an expert scientific committee about asthma control and the use of telemedicine with this purpose. A dedicated scientific committee validated the questionnaire, which included questions about the participants’ profile and the use of technological tools at a personal level or in clinical practice.The experts expressed their agreement with a Likert-scale of 9 values: 1–3 was considered no agreement, 4–6 neutral, and 7–9 agreement. A rate ≥70% with the same answer was considered consensus. Site: The questionnaire was programmed and distributed as an internet-based survey. Participants: A pre-selected sample of 75 experts with experience in telemedicine (pulmonology, allergology, family medicine, nursing and community pharmacy) responded to a Delphi-like questionnaire composed by six questions and 52 items. Interventions: Consultation was performed in two consecutive waves: the first wave was carried out from 12th of July to 8th of September of 2021; the second wave, from 25th of October to 12th of November of 2021. Main measurements: Three questions about asthma control (actions for achieving or maintaining control of asthma at every visit, current problems that affect asthma control, and potential solutions to offset such problems), and three questions about the impact of telemedicine in asthma control (potential benefits of telemedicine, and potential reticence about telemedicine among both patients and healthcare professionals) were included. Results: From the 52 items inquired, 35 were agreed by consensus. The actions for achieving or maintaining control of asthma, the problems that affect asthma control, and their potential solutions were agreed by consensus. The potential benefits of telemedicine were validated by consensus. None of the potential reservations of patients about telemedicine were validated, while five out of 14 potential reservations of healthcare professionals were agreed by consensus. Conclusions: The COMETA consensus provides a current picture of the main problems for achieving asthma control, the benefits and the reservations about the use of telemedicine in the Spanish setting, and offers solutions. A wide interest in implementing telemedicine has been observed, although current limitations need to be overcome. Resumen: Objetivos: Recoger las perspectivas y explorar el consenso de los expertos en las recomendaciones para un mejor control del asma y el uso de la telemedicina entre los profesionales que tratan pacientes con asma. Diseño: Se diseñó un cuestionario con la metodología Delphi para analizar el nivel de acuerdo en varias recomendaciones formuladas por un comité científico experto sobre el asma y el uso de la telemedicina. Un comité experto validó el cuestionario, que incluyó preguntas sobre el perfil de los participantes y el uso de las herramientas tecnológicas a nivel personal y en la práctica clínica.Los expertos expresaron su acuerdo con una escala de Likert de 9 valores: 1-3 se consideró sin acuerdo, 4-6 neutral y 7-9 de acuerdo. Se consideró consenso cuando ≥70% de los participantes respondieron la misma respuesta. Ubicación: La consulta se realizó online. Participantes: Una muestra preseleccionada de 75 expertos con experiencia en telemedicina (neumología, alergología, medicina familiar, enfermería y farmacia comunitaria) respondió a un cuestionario formado por 6 preguntas y 52 ítems. Intervenciones: La consulta se realizó en dos olas consecutivas: la primera ola tuvo lugar desde el 12 de julio al 8 de septiembre de 2021. Y la segunda ola, del 25 de octubre al 12 de noviembre de 2021. Medidas principales: En el cuestionario se incluyeron tres preguntas sobre el control del asma (acciones para lograr y/o mantener el control del asma, problemas actuales que afectan a este control y las posibles soluciones), y tres preguntas sobre el impacto de la telemedicina en el control del asma (potenciales beneficios de la telemedicina y la posible reticencia a telemedicina entre los pacientes y los profesionales sanitarios). Resultados: De los 52 ítems consultados, en 35 de ellos se alcanzó el consenso. Se acordaron por consenso las acciones para lograr o mantener el control del asma, los problemas que afectan al control del asma y sus posibles soluciones. Los beneficios potenciales de la telemedicina fueron validados por consenso. Ninguna de las posibles reservas de los pacientes sobre la telemedicina fue validada, mientras que cinco de las 14 posibles reservas de los profesionales sanitarios se acordaron por consenso. Conclusiones: El consenso COMETA ofrece una imagen actual de los principales problemas para lograr el control del asma, los beneficios y las reservas sobre el uso de la telemedicina en el ámbito español, y ofrece soluciones. Se ha observado un amplio interés por parte de los profesionales sanitarios por implementar la telemedicina, aunque es necesario superar las limitaciones actuales.

Resumen: Antecedentes y objetivo: Los glucocorticoides sistémicos (GCS) se han utilizado ampliamente para tratar el asma desde que se describió por primera vez su eficacia en esta enfermedad. Actualmente sabemos que su uso está asociado con la aparición de efectos adversos (EA), como la osteoporosis o la insuficiencia suprarrenal. Este es un estudio observacional basado en la metodología Delphi. El cuestionario constaba de 4 bloques principales: generalidades de los GCS; tratamiento de mantenimiento; tratamiento en ciclos cortos, y EA. Materiales y métodos: Un panel de 48 expertos profesionales alergólogos y neumólogos respondieron a 2 rondas de un cuestionario de 68 enunciados. Resultados: Se consensuaron definiciones y hubo acuerdos sobre el uso apropiado de los GCS en el tratamiento del asma grave. Los expertos consensuaron que el uso de los GCS se debe minimizar en lo posible y estuvieron de acuerdo en un esquema de retirada gradual y progresivo en caso de terapias de mantenimiento. Además, destacaron la necesidad de estandarizar el procedimiento de control de la medida de GCS administrado tanto en ciclos cortos como en terapias de mantenimiento a fin de controlar mejor la carga acumulada de los pacientes que reciben dicho tratamiento y evitar la aparición de EA. Conclusiones: Este documento de consenso pretende aunar las recomendaciones de los expertos en el manejo del asma respaldadas por la evidencia científica con el objetivo de impulsar la reducción en el uso de GCS en el ámbito español. Abstract: Background and aim: Since their effectiveness was initially demonstrated, oral corticosteroids (OCS) have been routinely used to treat asthma. We now know that their usage is linked to the development of side effects such osteoporosis and adrenal insufficiency. This is an observational study based on Delphi methodology. The questionnaire was divided into 4 sections: OCS generalities, maintenance treatment, short-term treatment, and adverse events. Materials and methods: Two rounds of a 68-item questionnaire were completed by a panel of 48 allergists and pneumologists. Results: Definitions were agreed upon, as was the proper use of OCS in the treatment of severe asthma. The experts agreed that the use of OCS should be minimized as much as possible and that in the event of maintenance treatments, a slow and progressive tapering strategy should be used. They also emphasized the importance of standardizing the technique for measuring the amount of SCG delivered in both cases. Conclusions: This consensus document attempts to bring together scientifically supported suggestions from specialists in the management of asthma to reduce the use of OCS in Spain.

This review aims at identifying research trends in medical education focused on clinical reasoning and argumentation for the resolution of specific problems in the area of medicine. A systematic literature review was performed comprising articles from 2015 to 2019 with the keywords; Clinical Reasoning and Medical Education. A total of 191 articles were initially found, of which 52 were analyzed as they were in accordance with the criteria designed for the study. Most studies had a qualitative design and, although they were focused on the teaching process, there was a fundamental recognition of the student in the design of strategies and methods. The theoretical and thematic categories most addressed were new trends in teaching strategies, resolution of medical practice problems, and the decrease in diagnostic error. This type of study allows the delimitation of fields of research, and clarifies the state of progress, approaches, and interests of researchers dedicated to this particular area. It is concluded that the investigation of teaching practices that lead to the promotion of argumentation in students has become a field of exploration, and introduces new perspectives in relation to the training process. This supports the need to integrate the method into teaching and learning processes of health sciences, as well as in the theoretical and methodological developments resulting from research on specific didactics. Resumen: En vista del creciente interés por la aplicación de las teorías educativas, y más específicamente de las didácticas de dominio específico a los procesos de enseñanza y aprendizaje de la medicina, se hace necesario delimitar los campos de intervención que den pie a nuevas propuestas metodológicas, donde se privilegie la promoción del pensamiento crítico y el razonamiento científico, enfocados en la resolución de problemas en salud. Esta revisión pretende identificar las tendencias de investigación en educación médica con respecto al razonamiento clínico y a la argumentación para la resolución de problemas específicos del área de la medicina. Se llevó a cabo una revisión sistemática de la literatura, incluyendo artículos desde el 2015 hasta el 2020, con las palabras clinical reasoning y medical education. Inicialmente, se encontraron 191 trabajos, de los cuales se terminaron analizando 52, según los criterios diseñados para la investigación. La mayoría de los estudios tienen un diseño cualitativo y están centrados en el proceso de enseñanza, aunque enfocados en los estudiantes. Las categorías teóricas y temáticas más abordadas son las nuevas tendencias en estrategias de enseñanza, la resolución de problemas de la práctica médica y la disminución del error diagnóstico.Este tipo de estudios permite delimitar los campos de investigación y dejar claro el estado de avance, los enfoques y los intereses de los especialistas dedicados a estas áreas particulares. La investigación de las prácticas docentes que conllevan a la promoción de la argumentación en los estudiantes se ha convertido en un campo de exploración y de planteamiento de nuevas perspectivas en relación con el proceso de enseñanza y aprendizaje, lo cual apoya la necesidad de incorporar a este último concerniente a las ciencias de la salud, los desarrollos teóricos y metodológicos productos de la investigación de las didácticas específicas.

Objective: The aims that we set in this study were to analyse the kinematic and kinetic changes in the lower limbs of cyclists when using the utility model, nº of publication ES 1078023, which consists of a system of cleats with an exact omnidirectional adjustment and without oscillations between the shoe and the pedal. Methods: This is a quasi-experimental, longitudinal and prospective study with a non-randomized sampling. The sample was made up of 34 cyclists. The variables studies focused on the kinematics of each joint of the lower limb in three planes and the kinetics in the function of the angular position of the cleat. They had the Bioval® system put in place, through which the kinematic parameters were recorded at the points marked on the lower limb for 20 s. Three systems were used for the kinetics (Power Tap, Rotor and Pioneer), recording the power developed for 1 min for each of the study situations. Results: Regarding the kinematic variables, statistically significant differences were found for the three planes in all of the structures studied. As for the kinetics, statistically significant differences were also observed, both when analyzing them globally and when doing so for each of the systems. Conclusions: The variation in the rotational position of the cleat influences both the cyclist’s kinematics and dynamics.

Contextualización: Desde el protocolo de Kioto y la Cumbre de París, la reducción de gases de efecto invernadero, GEI, causados por la actividad antrópica, en el mundo ha cobrado vital importancia, dado los indicadores críticos de emisión con efectos nocivos en el clima. Vacío de investigación: Dentro de este panorama, investigaciones preliminares no tienen puntos de acuerdo sobre qué combustible genera menores emisiones de CO2: el diésel o el biodiésel. Propósito del estudio: Por esta razón, y buscando fundamentar información que permita proponer alternativas energéticas sustentables a partir de sustitutos de combustibles fósiles, fue necesario cuantificar y evaluar las emisiones de CO2, proveniente de motores diésel, para lo cual, se realizó el presente experimento que tuvo como propósito emplear diésel comercial B10 y biodiésel B100, y determinar sus emisiones de CO2, para ello se utilizó un motor de compresión de una planta eléctrica, con factores fijos como la cantidad de combustible a emplear establecida en 100 gramos. Metodología: El experimento, se apoyó estadísticamente con un diseño factorial de dos factores: tipo de diésel con dos niveles y potencia generada con tres niveles, y se determinó el efecto conjunto que estos factores producen en la emisión de CO2. Para esto, el motor fue sometido a la generación de tres potencias: 0,5kW-1,0kW-1,5kW; lo cual propició para cada nivel de potencia, diferentes caudales o consumos de combustible y aire, y diferentes emisiones de CO2. Resultados y conclusiones: Los resultados indican que: empleando cualquier combustible la relación aire/combustible es menor y la fracción molar de CO2 es mayor cuando se genera más potencia; el experimento mostró que la fracción molar de B10 es mayor que la del B100: 0,15 y 0,13, respectivamente, con lo cual no puede generalizarse que la mayor emisión de CO2 la propicie el diésel comercial, pues la mayor o menor emisión depende de la composición química del combustible.

Resumen: A pesar de los avances terapéuticos disponibles actualmente, el grado de control del asma es escaso. Dicho control se basa en evaluar al paciente, ajustar el tratamiento y revisar la respuesta al mismo. En situaciones normales, el seguimiento y el control del asma se realizan mediante visitas presenciales secuenciales. Sin embargo, debido a las medidas de bioseguridad y distanciamiento para evitar la transmisión de la enfermedad durante una pandemia, ese seguimiento y control se ven limitados. Así es como ha surgido la teleasistencia, la cual dispone de una amplia evidencia publicada en asma. Aun así, no ha de entenderse como una forma de sustituir a las consultas presenciales, sino como una alternativa complementaria a las mismas, en las que se permite el seguimiento de los pacientes cuando no sea necesario o no se pueda realizar una consulta presencial. A través del proyecto COntrol como Meta en la Era de la Telemedicina en el Asma (COMETA), un grupo de expertos abordó en profundidad la enfermedad asmática, analizando de forma detallada los problemas existentes para poder alcanzar el control, y proponer soluciones ante situaciones como las que estamos viviendo actualmente con la pandemia de la COVID-19. Abstract: Despite the therapeutic advances currently available, asthma control is poor. Such control is based on assessing the patient, adjusting treatment, and reviewing the response to treatment. In normal situations, asthma is monitored and controlled by sequential face-to-face visits. However, due to biosecurity and distancing measures to avoid disease transmission during a pandemic, such monitoring and control is limited. This is how tele-assistance, which is available from extensive published evidence in asthma, has emerged. Even so, it should not be understood as a substitute for face-to-face consultations, but as a complementary alternative to them, in which patients can be monitored when a face-to-face consultation is not necessary or cannot be carried out. Through the COMETA project (COntrol como Meta en la Era de la Telemedicina en el Asma, Control as a Goal in the Age of Telemedicine in Asthma), a group of experts addressed in depth the asthmatic pathology, analyzing in detail the existing problems in order to achieve control and propose solutions to situations such as those we are currently experiencing with the COVID-19 pandemic.

Introduction Systemic lupus erythaematosus (SLE) is a chronic autoimmune disease of heterogeneous involvement. The disease may affect feet with a high prevalence of symptoms such as, for example, pain, forefoot and rearfoot deformities, and biomechanics dysfunctions. Custom-made foot orthoses (CMFO) have been previously reported to be effective in patients with other rheumatic diseases. However, as far as the authors know, there exist no studies about their effectiveness in SLE. This study aims at determining the effect of CMFO versus placebo flat cushioning insoles on pain, foot functionality, fatigue and quality of life in patients with SLE.Methods and analysis A randomised controlled trial would compare the effects of (1) CMFO and group B, which received a placebo, flat cushioning insoles, for 3 months. The main outcome measures are foot pain, foot functionality and foot-related disability. The secondary outcome measures are fatigue and quality of life.Ethics and dissemination The study has been approved by the Portal de Ética de la Investigación Biomédica de Andalucía ethical committee 1494-N-19. The results will be disseminated regardless of the magnitude or direction of effect.Trial registartion number Clinicaltrials.gov identifier NCT04098055.

La investigación indaga sobre el poder predictivo que el desempeño académico de secundaria tiene sobre el éxito académico en la universidad, al igual que las implicaciones de su incorporación en el proceso de admisión como moderador de la desigualdad social en nuestro entorno. Método: la población, estudiantes que ingresaron a la Universidad de Caldas en los años 2011-2012. Se acudió a los modelos de regresión múltiple y al cálculo de la importancia relativa de las variables regresoras para medir su capacidad predictiva. Se realizó un análisis comparativo de la incidencia que los resultados en las pruebas del ICFES tienen como reproductor de las desigualdades sociales. Resultados: el modelo obtenido contempla al desempeño en secundaria y al puntaje de admisión como variables predictoras del éxito universitario, explicando un 18.3% de la variabilidad total de los datos. La importancia relativa arroja que el 78.3% se le atribuye al desempeño en secundaria y el 21.7% al puntaje de admisión. Conclusión: los resultados obtenidos son consistentes con múltiples investigaciones en el área, por lo que la recomendación apunta a incorporar el rendimiento académico de secundaria en los procesos de admisión de las instituciones de educación superior.

Fundamento: Ante el aumento de personas con trastornos psiquiátricos en países de América Latina, se aprecia la necesidad de desarrollar estudios epidemiológicos para conocer la distribución de estos entre los varios grupos etarios; sin embargo, existen diferencias que van desde la elección de los instrumentos, hasta la selección y cálculo de la muestra, lo que afecta los resultados y sus conclusiones, como son el subregistro y el sobre diagnóstico de trastornos, o las dificultades en el acceso a los servicios de salud mental. Objetivo: Analizar diferencias metodológicas entre los estudios relacionados con la morbilidad psiquiátrica en la población general y en servicios de atención primaria, asimismo los diferentes hallazgos obtenidos en esas investigaciones. Conclusiones: Los estudios de morbilidad psiquiátrica a partir del indicador prevalencia realizados en América Latina son heterogéneos e incluyen instrumentos, sistemas de clasificación, sujetos y cálculo de muestras diferentes, así como sus resultados, por lo que es pertinente enfocar el diseño de este tipo de investigación ajustado a las realidades locales y recursos disponibles para de esta manera definir estrategias que aporten a la planificación de servicios y el desarrollo de políticas de salud mental en esta región.

El artículo es resultado parcial de la investigación “Semiosis de la Pedagogía, el Currículo y la Didáctica” y se focaliza en la categoría pedagogía. Es un estudio cualitativo que tiene como objetivos describir y valorar las ideas que en torno al campo de la pedagogía manifiestan profesores y estudiantes de la Universidad de Caldas, Colombia. En lo metodológico tuvo en cuenta una muestra intencional de 168 sujetos que aplicaron a un instrumento de 39 ítems de los cuales 11 aludían a asuntos relacionados con la pedagogía. El análisis se hizo a partir de las valoraciones dadas a los diferentes ítems utilizando herramientas de Excel. Se destacan en los resultados valoraciones importantes que se hacen de la pedagogía como arte o como campo de conocimiento y de la experiencia como un componente central en la constitución de la formación y del conocimiento pedagógico de los docentes.