Introdução: O ensino em cirurgia deve acompanhar a evolução das técnicas, procedimentos e tecnologia. Desde a década de 90 a videocirurgia vem se desenvolvendo e hoje é a primeira escolha para muitos procedimentos em cirugia geral. Com características diferentes da cirurgia convencional, os residentes treinaram em simuladores para adaptação. A literatura médica mundial já apresenta programas consagrados para treinamento entre eles os Fundamentos da Cirurgia Laparoscópica (FLS). A avaliação das habilidades técnicas cirúrgicas é uma ferramenta importante em programas de residência médica. Objetivo: Avaliar o impacto do treinamento através de aquisição de habilidades dos médicos residentes em cirurgia geral antes e após treinamento teórico-prático em videocirurgia utilizando um simulador de baixa fidelidade baseado em exercícios do FLS. Método: Estudar de modo prospectivo a aquisição de habilidades de médicos residentes em cirurgia geral de primeiro e segundo ano (R1 e R2), antes e após realização de treinamento teórico-prático pré-definido. Conclusão: Houve melhora significativa com o treinamento atingindo níveis de conhecimento e aprimoramento semelhantes aos trabalhos da literatura mundial. A melhoria no desempenho dos residentes foi evidente em ambos os grupos da amostra. Aqueles do primeiro ano atingiram a concentração de conhecimento após o treinamento semelhante ao desempenho dos residentes de segundo ano na avaliação inicial, destacando que o treinamento sequenciado realizado equivale a um ano de prática no programa de residência geral de cirurgia

Introduction: Teaching in surgery must follow the evolution of medical techniques, procedures and technology. Since the 90s videosurgery has been developing and nowadays is the gold standard for many procedures in general surgery. As there are different characteristics from conventional surgery, residents need to practice in order to adapt to simulators. The world medical literature has established many training programs among them the Fundaments of laparoscopic Surgery (FLS). Evaluation of surgical technical abilities is a major tool for the residency programs. Objectives: To assess the effect of training acquiring skills of residents at first and second postgraduated level year (PGY1 and PGY2) before and after practice using low fidelity simulator based on tasks from FLS. Methods: A prospective study was conducted to determinate skills acquisition of residents at first and second postgraduated level year l (PGY1 and PGY2) before and after standardized practice using low fidelity simulator. Conclusions: There was a significant improve of the technical abilities reaching levels of improvement. Resident’s performance was evident in the sample groups. First year residents (PGY1) achieved knowledge retention after training similar to the performance of second in the initial assessment, suggesting that the sequenced training carried out is equivalent to one year of practice in the general surgery residency program

Introdução: O ensino em cirurgia convencional foi tradicionalmente baseado no modelo halstediano do “see one, do one and teach one” (veja um, faça um e ensine um); porém, com a bem sucedida propagação da cirurgia videolaparoscópica precisou ser adaptado para um novo modelo do “do many, mentored always” (fazer vários, sempre supervisionado). A nova era da cirurgia demanda treinamento sequencial, com crescente complexidade e repetição supervisionada para adquirir habilidades especificas prévias ao primeiro ato operatório. Objetivo: Desenvolver modelo para ensino e treinamento em videocirurgia com plataforma de baixo custo, fácil execução e baixa fidelidade com tarefas que utilizam materiais sintéticos. Método: Construiu-se com materiais de baixo custo plataforma utilizando apenas placa de madeira, poucos materiais de ferragem (parafuso simples, parafuso com porca tipo borboleta, gancho com rosca), folha de EVA (etileno acetato de vinila), tinta branca para artesanato e caneta hidrográfica. A amostra-teste foi composta por 15 cirurgiões gerais com mais de 10 anos de experiência em videolaparoscopia. Iniciou-se a avaliação com um vídeo explicativo com duração de 20 min. A seguir, cada cirurgião executou 5 tarefas gravadas para posterior análise e pontuação. Mediu-se as habilidades de acordo com a pontuação. Resultados: A plataforma foi útil e eficaz em reproduzir as atividades utilizadas para replicação do programa comparativo do Fundaments of Laparoscopic Surgery. A amostra de cirurgiões atingiu o tempo alvo definido como padrão pelo programa. Conclusão: A plataforma elaborada com materiais de baixo custo é de fácil aquisição, mostrou-se modelo eficaz para treinamento em videocirurgia, de fácil replicabilidade e construção, adaptável a vários modelos de tarefas, e feita com materiais sintéticos.

Introduction: Teaching in conventional surgery has traditionally been based on the Halstedian model of “see one, do one, and teach one”. However, with the widespread success of videolaparoscopic surgery, the teaching method needed to be adapted to a novel “Do many, always mentored” model. The modern era of surgery demands sequential training with progressively increasing complexity and supervised repetition, in order to acquire specific skills prior to the first surgical procedure. Objective: To develop a new experimental teaching and training with low cost and low fidelity platform for laparoscopic surgery using synthetic materials, and simple manufacturing. Method: A platform was built using low-cost materials easily found in hardware stores, consisting of a wooden board and a few hardware materials (threaded bolt, wing nut and bolt, threaded hooks), EVA sheet (ethylene vinylacetat), white crafting paint, and felt-tip pen. The sample consisted of 15 general surgeons with more than 10 years of experience in videolaparoscopy. The evaluation began with an explanatory video lasting 20 min. Next, each surgeon performed 5 recorded tasks for later analysis and scoring. Skills were measured according to the stablished score. Results: The developed platform was useful and capable of reproducing the tasks performed based on the program of Fundaments of Laparoscopic Surgery. All the surgeons of the sample group achieved the target time proposed for the program. Conclusion: Was shown that the proposed platform can be built using easily obtainable and low-cost materials, and it proved to be an effective model for training in laparoscopic surgery, being easy to replicate and construct. Additionally, this platform can be easily adapted to various models of tasks using materials similar to those found in other training programs, that are widely practiced and have been globally validated.

ABSTRACT The development of the conceptual design of a technology for obtaining concentrated nitric acid at 99 % by weight from conventional nitric acid is presented through the analysis of 2 production alternatives, using a process simulator. For the conceptual design, process analysis techniques such as mathematical modeling, process simulation, optimization, economic analysis and Pinch analysis were used, among others. The process flow diagrams of both alternatives are also presented, as well as the validation of the mathematical model used to calculate the vapor - liquid balance in the water - nitric acid - magnesium nitrate system, as well as the sizing of the main equipment, optimizing the 2 feed and solvent inlet plates, as well as the heat transfer area of the heat exchange equipment. Finally, a summary of the economic analysis carried out for the two alternatives studied and the selection of the best one is presented.

RESUMEN Se presenta el desarrollo del diseño conceptual de una tecnología para la obtención del ácido nítrico concentrado al 99 % en peso a partir del ácido nítrico convencional mediante el análisis de 2 alternativas de producción, haciendo uso de un simulador de procesos. Para el diseño conceptual se utilizaron técnicas del análisis de proceso tales como la modelación matemática, la simulación de procesos, la optimización, análisis económico y análisis Pinch entre otras. Se presentan, además, los diagramas de flujo de procesos de ambas alternativas, la validación del modelo matemático empleado para el cálculo del equilibrio vapor - líquido en el sistema agua - ácido nítrico - nitrato de magnesio, así como el dimensionamiento de los equipos principales, optimizando los 2 platos de entrada de la alimentación y del solvente, así como el área de transferencia de calor de los equipos de intercambio térmico. Finalmente se expone un resumen del análisis económico realizado para las dos alternativas estudiadas y la selección de la mejor.

ABSTRACT The research relevance is predefined by the air travel number growth. Accordingly, the relevance of this issue is increasing, especially concerning air travel safety. Also, due to the increasing demand for international flights, it becomes essential to harmonize the standards and methodology of training aviation personnel. The research aims to consider the parameters of flight safety and the impact of the unification of training programs for aviation personnel. The conclusion that unification can significantly affect safety was made with the help of scientific and special methods, including analysis, synthesis, concretization, and generalization. An analysis of existing unification methods was conducted. The multi-crew pilot training program proved to be one of the most advanced compared to standard flight crew training programs. The method was determined to be a specialized training program tailored to the needs of the aviation industry and focused on training pilots for multi-crew and jet operations. The program is more challenging, intensive and dynamic, and includes a significant amount of simulator training. Traditional flight training programs, such as Private Pilot Licenses (PPL), Commercial Pilot Licenses (CPL), instrument qualification, and multi-engine rating, have a broader scope and provide pilots with more career opportunities. Simulator training has been identified as a critical component of many flight training programs and plays a vital role in flight safety. The study may be of interest to a range of readers concerned with the issue of standardizing aviation training and improving safety in aviation, including researchers, faculty, and students of higher education institutions in the aviation field.

Resumo Objetivo da Investigação: O objetivo deste artigo é avaliar e quantificar os impactos do desbravamento sobre os solos: a perda de fertilidade dos solos desbravados foi avaliada através de análises físico-químicas de solos florestais (azinheiras), de pastagens e de parcelas desbravadas transformadas em terras aráveis há muito tempo (+10 anos). Metodologia: A simulação da precipitação (utilizando um simulador simples) foi utilizada para avaliar o impacto da limpeza e do cultivo no comportamento hidrodinâmico do solo. Resultados: A degradação das florestas tem consequências negativas para o ambiente natural. Em primeiro lugar, o solo torna-se instável devido aos efeitos do pisoteio do gado e das lavouras sucessivas. Em segundo lugar, verifica-se uma redução das reservas do solo, com uma diminuição da matéria orgânica de 33,61% do seu nível inicial e um aumento dos níveis de azoto mineral de 1,61 para 7,73 mg/100g. Em terceiro lugar, as perdas de solo por erosão hídrica atingem 0,85 t/ha para uma sequência de precipitação de 80 mm h-1 durante 45 minutos. Os resultados experimentais desta análise na depressão de Ain Nokra mostram o papel significativo de ecossistemas florestais bem preservados na proteção do solo contra a erosão hídrica e na conservação dos recursos hídricos. Originalidade/valor: Este estudo representa a primeira simulação da erosão em Ain Nokra (Médio Atlas). De um ponto de vista científico, este artigo aborda o papel da vegetação na proteção dos solos contra a erosão, bem como o seu impacto no enriquecimento do solo com matéria orgânica.

Abstract Research Purpose: The aim of this article is to evaluate and quantify the impacts of land clearing on soils: the loss of fertility of cleared soils was assessed using physico-chemical soil analyses under forest (Holm Oak), and in rangeland and cleared plots transformed into arable land a long time ago (+10 years). Methodology: Rainfall simulation (using a simple simulator) was used to assess the impact of land clearing and cultivation on soil hydrodynamic behavior. Results: The results show that forest degradation has negative consequences for the natural environment. Firstly, the soil becomes unstable under the effects of trampling by livestock and successive ploughing. Secondly, soil reserves are reduced, with organic matter dropping from 33.61% of its initial level, and mineral nitrogen rising from 1.61 to 7.73 mg/100g. Thirdly, soil losses through water erosion reached 0.85 t/ha for a precipitation sequence of 80 mm h-1 for 45 minutes. The experimental results of this analysis in the Ain Nokra depression demonstrate the significant role of well-preserved forest ecosystems in protecting soil against water erosion and conserving water resources. Originality/value: This study represents the first simulation of erosion at Ain Nokra (Middle Atlas). From a scientific point of view, this article addresses the role of vegetation in preserving soils against erosion, as well as its impact in enriching the soil with organic matter.

Resume Objectif de recherche: L’objectif de cet article consiste à évaluer et quantifier les impacts de défrichement sur les sols : La perte de fertilité des sols défrichés a été évaluée à l'aide d'analyses physico-chimiques des sols sous forêt (Chêne vert), et dans des terrains de parcours et les parcelles défrichées Transformées en terres arables depuis longtemps (+10 ans). Méthodologie: La simulation de pluies (avec simulateur simple) a été utilisée pour évaluer les impacts du défrichement et de la mise en culture sur le comportement hydrodynamique du sol. Résultats: Les résultats obtenus montent que la dégradation des forêts, a des conséquences négatives sur le milieu naturel. Premièrement le sol devient instable sous les effets du piétinement du cheptel et les labours successifs. Deuxièmement il y a réduction des réserves du sol, à savoir la matière organique qui baisse de 33,61% de sa teneur initiale, l’augmentation du taux l’azote minéral est passé de 1,61 à 7,73 mg/100g. Troisièmement, les pertes en sols par l'érosion hydrique ont atteint 0,85 t/ha pour une séquence de précipitation de 80 mm h-1 pendant 45 minutes. Les résultats expérimentaux de cette analyse au niveau de la dépression Ain Nokra montrent le rôle non négligeable des écosystèmes forestiers bien conservés dans la protection du sol contre l'érosion hydrique, et dans la conservation des ressources en eau. Originalité/Valeur: Cette étude représente la première simulation de l'érosion au niveau d'Ain Nokra (Moyen Atlas). Sur le plan scientifique, cet article aborde le rôle de la végétation dans la préservation des sols contre l'érosion, ainsi que son impact dans l'enrichissement du sol en matières organiques.

Abstract: The present systematization of experience evaluated the use of a low-cost electric/electronic device, attached to a computer mouse, to facilitate the use of the mouse by elderly people with specific manual motor difficulties, who encounter limitations when performing the double click (they lack sufficient strength to generate the necessary pressing speed). The population observed was 76 adults, aged between 60 and 85 years. The objective of the observation was to analyze the suitability of the new tool to the needs of the participants from a socio-technical and interdisciplinary perspective. Data collection was based on group interviews and surveys. It was found that participants over 70 years of age expressed a preference for the new device over the mouse, while the 60-70 age group expressed a preference for the traditional mouse. This result is consistent with the evidence of difficulty in double-clicking, especially after the age of 70. It is concluded that this difference in the perception of the technical aid (double-click simulator) points out (a) the need for an appropriate segmentation of computer courses for older adults, taking into account as a criterion, for example, the operative skills of the participants; and (b) the importance of carrying out a previous diagnosis of these skills, to determine in which cases to use technical aids and which are the most appropriate.

Resumo: Essa sistematização de experiência avaliou o uso de um dispositivo elétrico/eletrônico de baixo custo, acoplado a um mouse de computador, para facilitar o uso do mouse por idosos com dificuldades motoras man- uais específicas, que encontram limitações ao clicar duas vezes (eles não têm força suficiente para gerar a velocidade necessária para clicar). A população observada foi de 76 adultos, com idade entre 60 e 85 anos. O objetivo da observação foi analisar a adequação da nova ferramenta às necessidades dos participantes a partir de uma perspectiva sociotécnica e interdisciplinar. A coleta de dados foi baseada em entrevistas em grupo e pesquisas. Verificouse que os participantes com mais de 70 anos de idade expressaram preferência pelo novo dispositivo em vez do mouse, enquanto a faixa etária de 60 a 70 anos expressou preferência pelo mouse tradicional. Esse resultado é consistente com a evidência de dificuldade em clicar duas vezes, especialmente na faixa etária acima de 70 anos. Concluise que essa diferença na percepção da ajuda técnica (simulador de duplo clique) alerta para (a) a necessidade de uma segmentação adequada dos cursos de informática para idosos levando em conta como critério, por exemplo, as habilidades operacionais dos participantes; e (b) a importância de se realizar um diagnóstico prévio dessas habilidades, para determinar em quais casos utilizar as ajudas técnicas e quais são as mais adequadas.

Resumen: La presente sistematización de experiencia evaluó la utilización de un dispositivo eléctrico/electrónico de bajo costo, anexado a un mouse de computadora, para facilitar la utilización del mouse por parte de personas mayores con dificultades motoras manuales específicas, quienes encuentran limitaciones a la hora de realizar el doble clic (carecen de fuerza suficiente para generar la velocidad necesaria de pulsado). La población observada fue 76 adultos, de entre 60 y 85 años. El objetivo de la observación fue analizar la adecuación de la nueva herramienta a las necesidades de los participantes desde una perspectiva socio-técnica e interdisciplinar. La recolección de datos se basó en entrevistas grupales y en encuestas. Se halló que los participantes mayores de 70 años manifestaron preferencia por el nuevo dispositivo respecto del mouse, mientras que el grupo de 60-70 manifestó una preferencia por el mouse tradicional. Este resultado es coherente con la evidencia de la dificultad para el doble cliqueo especialmente a partir de los 70 años. Se concluye que esta diferencia en la percepción de la ayuda técnica (simulador de doble clic) advierte: sobre (a) la necesidad de una segmentación apropiada de los cursos de informática para adultos mayores teniendo en cuenta como criterio, por ejemplo, las habilidades operativas de los participantes; y sobre (b) la importancia de realizar un diagnóstico previo de las mismas, para determinar en qué casos utilizar ayudas técnicas y cuáles son las más apropiadas.

Resumo A química estrutural pode ser discutida com substâncias aromáticas, aplicando os recursos digitais PUBCHEM - banco de dados de informações químicas com estruturas 3D interativas, SDBS - banco de dados de espectros de RMN-1H e IV experimentais, NMRDB- simulador de espectros de RMN-1H com inteligência artificial (IA), para a elaboração de atividades interativas que promovam a visualização molecular em situações de estudo (SE). Foram selecionadas cinco substâncias sendo que quatro delas formam dois pares de isômeros estruturais, um par com a composição C5H10O2 com grupos funcionais distintos, o formato de isobutila - aroma da amora e o etanoato de butila - aroma da maçã; o segundo par tem a fórmula química C9H10O2, acetato de benzila - aroma da pera e fenilacetato de metila - aroma de mel, tendo as duas moléculas grupos funcionais idênticos. Foi sugerido o uso combinado de recursos digitais como objetos de aprendizagem (OAs) para a visualização direta (PUBCHEM) e indireta das estruturas químicas (NMRDB e SDBS) dessas moléculas, como uma introdução à análise de espectros de RMN-H usando a inteligência artificial do simulador NMRDB para atividades interativas em uma SE envolvendo química estrutural na formação inicial ou continuada de professores de química. Além de proporcionar a visualização molecular, na prática da química, a atividade interativa apresentada pode contribuir para o desenvolvimento da curiosidade científica, da argumentação com base em fatos, dentre outras competências gerais da Base Nacional Comum Curricular (BNCC).

Abstract Structural chemistry can be discussed with aromatic substances by applying digital resources PUBCHEM - chemical information database with interactive 3D structures, SDBS - database of experimental 1H-NMR and IR spectra, NMRDB- simulator of 1H- NMR with artificial intelligence (AI), for the development of interactive activities that promote molecular visualization in study situations (SE). Five substances were selected, four of which form two pairs of structural isomers, one pair with the composition C5H10O2 with distinct functional groups, the isobutyl formate - blackberry aroma and the butyl ethanoate - apple aroma; the second pair has the chemical formula C9H10O2, benzyl acetate - pear aroma and methyl phenylacetate - honey aroma, both molecules having identical functional groups. The combined use of digital resources as learning objects (LOs) for the direct (PUBCHEM) and indirect visualization of chemical structures (NMRDB and SDBS) of these molecules was proposed, exemplifying an introduction to the analysis of 1H-NMR spectra with the AI of the NMRDB simulator, for interactive activities in a SE with structural chemistry in the training (initial or continuing) of chemistry teachers. In addition to providing molecular visualization in the practice of chemistry, the interactive activity presented can contribute to the development of scientific curiosity, argumentation based on facts, among other general skills of the National Common Curricular Base (Base Nacional Comum Curricular -BNCC).

The advancement of wireless technology is increasing the demand for scarce spectrum. Cognitive radio ad hoc networks (CRAHNs) were proposed as a solution to spectrum scarcity which is also deployed in combat. However, military cognitive radio ad-hoc networks (MCRAHNs) are subject to destruction and frequent link breakages. The challenge with MCRAHNs routing is the timing-out of packets. This paper proposes the spectrum-aware transitive multi-cast on-demand distance vector (SAT-MAODV), optimised for throughput and delay. The relay nodes are selected based on zonal data and mobility. This is achieved through handshaking and sharing of location data. The nodes are expected to store location data of nodes encountered, which is used in routing and in determining the movement of the node. The mobility of military nodes is organised and structured, which simplifies routing. The SAT-MAODV was evaluated in network simulator 2 and the results show that the scheme is effective. Using SAT-MAODV instead of xWCETT, it reduced routing path and node relay delay by at least 65% and 13% respectively, and increased achievable throughput by 31%. It also improved the delivery ratio by 9% while reducing latency by 27% in comparison with MARSA. Categories · Networks ~ Network protocols, Network layer protocols, Routing protocols

Abstract Introduction Rubber band ligation is a minimally invasive outpatient hemorrhoid treatment with low cost, low complication rates, and rapid realization. It is performed with the aid of an anoscope and uses a rubber ring that surrounds the hemorrhoidal nipple, causing compression of the vascular structures of the tissue, leading to necrosis and remission of the hemorrhoid. No device for training this essential procedure for treating this pathology has been identified in the literature. Therefore, we aim to develop a low-cost simulator for training hemorrhoidal rubber ligation. Methods The model was constructed using PVC pipe wrapped in neoprene fabric. Hemorrhoidal nipples and the pectineal line were also simulated using fabric and sewing threads. The procedure is performed with conventional anoscope and ligature forceps. Conclusion The device in question is a low-cost simulation model designed to train the skills required to perform a rubber band ligation and review the basic anatomy of the anal canal during anoscopy. Given these qualities, the model can be used for academic training due to its low cost and simplicity of application. rates realization nipple tissue literature Therefore lowcost threads forceps anoscopy qualities application

Abstract Objective To validate the low-cost model for arthroscopy training and analyze the acceptance and usefulness of the developed simulator in medical teaching and training. Method Ten medical students, ten third-year orthopedic residents, and ten shoulder surgeons performed predetermined tasks on a shoulder simulator twice. The parameters used were time to complete the tasks, number of looks at the hands, GOALS score (Global Operative Assessment of Laparoscopic Skills) and comparison between groups and within groups. An adapted Likert scale was applied addressing the individuals' impressions about the simulator and its applicability. Results In the intergroup comparison, the shoulder surgeons had better scores and times than the other groups. When the tasks were repeated, the group of surgeons had a 59% improvement in time (p < 0.05), as did the group of medical students. In the GOALS score, shoulder surgeons had consistently better scores than the other groups. And when we evaluated the evolution from the first to the second test, the group of surgeons and the group of academics had a statistically significant improvement (p < 0.05). In terms of lookdowns, there was a decrease in all groups. There was consensus that the simulator is useful in training. Conclusion The simulator developed allowed the differentiation between individuals with different levels of training in arthroscopic surgery. It was accepted by 100% of the participants as a useful tool in arthroscopic shoulder surgical training.

Resumo Objetivo Validar o modelo de baixo custo para treinamento em artroscopia e analisar a aceitação e utilidade do simulador desenvolvido no ensino e treinamento médico. Método Dez acadêmicos do curso de medicina, dez residentes do terceiro ano em ortopedia e dez cirurgiões de ombro realizaram tarefas pré determinadas em um simulador de ombro duas vezes. Os parâmetros utilizados foram o tempo para completar as tarefas, quantidade de olhares para as mãos, escore de GOALS (Global Operative Assessment of Laparoscopic Skills) e comparados entre os grupos e intragrupos. Uma escala de Likert adaptada foi aplicada abordando as impressões dos indivíduos acerca do simulador e de sua aplicabilidade. Resultados Na comparação intergrupos, os cirurgiões de ombro tiveram melhores escores e tempos que os demais grupos. Quando as tarefas foram repetidas, o grupo de cirurgiões, teve uma melhora de 59% no tempo (p < 0,05), assim como no grupo de acadêmicos. No escore de GOALS os cirurgiões de ombro apresentaram escores consistentemente melhores que os demais grupos. E quando avaliamos a evolução do primeiro para o segundo teste, o grupo de cirurgiões e o grupo de acadêmicos tiveram melhora estatisticamente significante (p < 0,05). No quesito de lookdowns houve diminuição em todos os grupos. Houve consenso em que o simulador é útil no treinamento. Conclusão O simulador desenvolvido permitiu a diferenciação entre indivíduos com diferentes níveis de treinamento em cirurgia artroscópica. Foi aceito por 100% dos participantes como uma ferramenta útil no treinamento cirúrgico artroscópico do ombro.

RESUMEN El proceso de compactación de los residuos agroindustriales, constituye actualmente una forma apropiada de almacenamiento y distribución. El bagazo de caña, a pesar de su uso variado, es uno de los desechos que puede compactarse y aprovecharse como materia prima alternativa, para la bioeléctrica cubana. No se ha observado en Cuba que exista a nivel industrial una planta para el peletizado, lo que pudiera contribuir al encadenamiento productivo entre las Empresas Azucareras del territorio centro oriental y la Bioeléctrica. El objetivo de este trabajo es analizar alternativas tecnológicas, para la producción de pellets a partir del bagazo de caña, empleando el simulador SuperPro Designer, de manera que permita la selección de una variante económicamente factible, como forma de encadenamiento productivo. Para dicha selección serán utilizados los indicadores: VAN, TIR y PRI.

ABSTRACT The process of compacting agro-industrial waste is currently an appropriate form of storage and distribution. Sugarcane bagasse, despite its varied use, is one of the wastes that can be compacted and used as an alternative raw material for the Cuban bioelectric plant. It has not been observed in Cuba that there is a plant for pelletizing at the industrial level, which could contribute to the productive chain between the Sugar Companies of the eastern central territory and the Bioelectric. The objective of this work is to analyze technological alternatives, for the production of pellets from sugarcane bagasse, using the SuperPro Designer simulator, so that it allows the selection of an economically feasible variant, as a form of productive chain. For this selection, the indicators will be used: NPV, IRR and PBT.

Resumen Los nuevos medios de comunicación han creado oportunidades para medir directamente cómo los adolescentes responden a situaciones de agresión. Presentamos a SIMA, un simulador de chats digitales creado para imitar interacciones agresivas en línea en una situación de conflicto. Los adolescentes son invitados a ser parte de un chat digital para discutir temas controversiales (p. ej., maltrato animal). En realidad, las interacciones están todas preprogramadas a excepción de las intervenciones de quienes participan. Dos supuestos miembros del chat tienen un conflicto programado para escalar de forma rápida con insultos agresivos. Participaron estudiantes de sexto y séptimo grado (principalmente de 12 a 14 años; n = 287) de un colegio público (NSE bajo) y uno privado (NSE alto). Las respuestas a preguntas abiertas sugieren que la gran mayoría consideró que estaban participando en una interacción en línea real. Las ofensas agresivas hacia otros miembros del chat fueron muy comunes. SIMA abre muchas opciones para futuras investigaciones sobre el comportamiento de espectadores en interacciones agresivas en línea.

Abstract New media creates opportunities to directly measure how adolescents respond to aggressive situations. In this study, we report on SIMA, a simulator of digital chats, created to mimic online aggressive interactions within a conflict situation. Adolescents were invited to be part of a digital chat where all interactions were pre-programmed, except for the participants’ interventions, to discuss controversial topics (e.g., animal maltreatment). Two chat members engaged in a conflict programmed to escalate quickly through aggressive insults. Sixth and seventh-grade students (mostly aged 12 to 14; n = 287) from one public school (low SES) and one private school (high SES) participated in the study. Responses to open questions after finishing the chat suggest that the great majority considered that they were taking part in a real online interaction. Aggressive offenses towards other members of the chat were very common. SIMA opens many options for further research about bystander behavior in aggressive online interactions.

Resumen: En la actualidad se ha comenzado a desplegar la tecnología de banda ancha 5G New Radio. Por lo tanto, se necesitan nuevas herramientas enfocadas al estudio del estándar y las condiciones de propagación. En este contexto, se presenta el desarrollo de un simulador 5G New Radio que permite experimentar con los diferentes parámetros de las señales, así como identificar las principales características a nivel de enlace y propagación de onda. Se analizaron las partes más esenciales del estándar y se introdujeron en el software, a partir de lo cual se pudo parametrizar el Physical Downlink Shared Channel y el Physical Uplink Shared Channel. En cuanto a la planificación de celdas urbanas, se incluyen dos cálculos: i) Mapas SINR que permiten la visualización de Signal to Noise and Interference Ratio (SINR) para un número parametrizable de gNodesB, potencia de transmisión, downtilt, etc. ii) Simulación de cobertura basada en ray-tracing en mapas 3D que tiene en cuenta también la permitividad y la conductividad de los materiales de edificios y terreno. Además, para la caracterización del canal, el simulador presenta el Perfil de Retardo de Potencia (PDP), y si hay movimiento, el desplazamiento Doppler se representa en la función de dispersión. El resultado es un simulador parametrizable que integra la generación de señales de 5G-NR y cálculos de cobertura para el despliegue de celdas urbanas de 5G, con una diferencia media para el caso del ray-tracing de 7.11 dB entre los valores medidos y calculados.

Abstract: Nowadays, the 5G New Radio broadband technology has begun to be deployed. Therefore, new tools focused on studying the standard and propagation conditions are needed. In this context, the development of a 5G New Radio simulator that allows experimentation with the different signal parameters, as well as to identify the main characteristics at the link level and wave propagation, is presented. The essential parts of the standard were analyzed and introduced into the software, from which the Physical Downlink Shared Channel and the Physical Uplink Shared Channel could be parametrized. Regarding urban cell planning, two calculations are included: i) SINR maps that allow the visualization of Signal to Noise and Interference Ratio (SINR) for parametrizable numbers of gNodeB, transmission power, downtilt, and so on; ii) Coverage simulation based on ray-tracing in 3D maps that also consider the permittivity and conductivity of buildings and terrain materials. Additionally, for channel characterization, the simulator presents the Power Delay Profile (PDP), and if there is movement, the Doppler shift is represented in the Scattering function. The result is a parameterizable simulator that integrates 5G-NR signal generation and coverage calculations for the deployment of 5G urban cells, with an average difference in the ray-tracing case of 7.11 dB between the measured and calculated values.

Resumen Objetivo: Evaluar las competencias logradas por estudiantes de medicina en la realización de una apendicectomía abierta y jareta en el modelo de simulación creado, evaluar el grado de satisfacción de su uso y determinar sus costos. Método: Estudio preexperimental de grupo único, prospectivo y longitudinal. Se evaluaron las competencias logradas por 24 alumnos de pregrado de medicina en la realización de una apendicectomía abierta y jareta en el simulador, mediante las pautas OSATS (Objective Structured Assessment of Technical Skills) a través de enseñanza virtual. Se realizó una encuesta a los alumnos para evaluar el simulador y se determinaron sus costos. Resultados: Hubo un incremento significativo en las pautas OSATS de las competencias logradas de 7 (pre-test) a 26 ± 5.71 puntos (pos-test final) (p = 0.0001) y una reducción del tiempo operatorio de 12 ± 3.81 minutos (primer pos-test) a 8 ± 2.02 minutos (pos-test final) (p = 0.0001). El 41% de los alumnos estuvieron totalmente satisfechos con los logros obtenidos y el 59% parcialmente satisfechos. El costo del simulador fue de 4.64 dólares americanos. Conclusiones: Los estudiantes lograron una mejora de sus competencias en la técnica quirúrgica. Este modelo de simulación es de bajo costo y presenta un nivel adecuado en la satisfacción de los logros obtenidos por los alumnos.

Abstract Objective: To evaluate the skills achieved by the undergraduate medical student in performing an open appendectomy and purse string in the simulation model created, to evaluate the degree of satisfaction of its use and to determine its costs. Method: Pre-experimental, prospective and longitudinal study. The skills achieved by 24 undergraduate medical students in performing an open appendectomy and purse string in the simulator were evaluated using the OSATS (Objective Structured Assessment of Technical Skills) through virtual teaching. A survey was conducted to the students to evaluate the simulator and its costs were determined. Results: There was a significant increase in the OSATS of the skills achieved, from 7 (pre-test) to 26 ± 5.71 points (final post-test) (p = 0.0001) and reduction in the operative time from 12 ± 3.81 minutes (first post-test) to 8 ± 2.02 minutes (final post-test) (p = 0.0001). 41% of the students were totally satisfied with the achievements obtained and 59% partially satisfied. The cost of the simulator was 4.64 USD. Conclusions: The students achieved an improvement in their skills in the surgical technique. This simulation model is low cost and presents an adequate level in the satisfaction of the achievements obtained by the students.