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

As funções do solo têm sido ameaçadas pelas atividades antrópicas, comprometendo a provisão de serviços ecossistêmicos e desiquilibrando o ciclo biogeoquímico do carbono. O sequestro de carbono no solo é uma solução para a restauração de solo degradado e para a mitigação climática. O estoque de carbono orgânico do solo (C-estoque) é um indicador que orienta projetos de restauração de ecossistemas e verifica resultados. No entanto, o solo é um sistema complexo e heterogêneo, sujeito às interações do sistema solo-planta-atmosfera, e é controlado por uma série de processos multidisciplinares que envolvem desde a captura de C da atmosfera até a retenção de C no solo. Ainda, há uma série de incertezas sobre conceitos, mecanismos de retenção e protocolos de mensuração do C-estoque. Por meio de uma revisão crítica da literatura, este artigo teve o objetivo de sintetizar conceitos com uma abordagem interdisciplinar, analisar oportunidades de pesquisa e avaliar aplicações sustentáveis à luz da engenharia ambiental. Os resultados apontam avanços conceituais na temática de estabilização da matéria orgânica no solo e ressaltam oportunidades de pesquisa sobre a dinâmica entre o carbono orgânico e o fluxo de água dentro de perfis de solo estruturados, o que pode ser compreendido por meio de conceitos da engenharia geotécnica. A revisão ainda sinaliza a ausência de um enquadramento multidisciplinar das variáveis que delimite a análise transdisciplinar do tema. Por fim, o C-estoque é um índice que pode ser utilizado em soluções de engenharia baseadas em C como um indicador dos resultados de restauração ecossistêmica.

Sustainable fish waste management is a critical issue linked to the United Nations Sustainable Development Goals, particularly SDG 12 (Sustainable Consumption and Production). Improper disposal of fish processing residues, including viscera, causes significant environmental problems by worsening pollution and wasting valuable biotechnological resources. In order to contribute to the solution of this economic and environmental challenge, this study sought to use wastewater from the processing of Nile tilapia (Oreochromis niloticus) viscera as a raw material for biosurfactant production by Penicillium citrinum UCP 1183. This strain was cultivated in alternative media composed of tilapia viscera wastewater and post-frying soybean oil, based on the concentrations established by a 22 full-factorial design. Biosurfactant production was verified in condition 4 of the full-factorial design, obtaining a surface tension of 36 mN/m. The biosurfactant showed an anionic and lipopeptide nature, moderate zeta potential, and excellent stability and emulsifying capacity. Hence, tilapia viscera wastewater proved to be an excellent substrate for sustainable biosurfactant production, minimizing the environmental impact of fish processing waste and promoting the circular economy.

Biosurfactants are surface-active molecules produced by microorganisms, whose amphiphilic structure enables them to reduce surface tension and stabilize emulsions. This study evaluated the production, characterization, stability, toxicity, and cleaning potential of a biosurfactant synthesized by Candida guilliermondii UCP 1592. The compound was produced in a medium containing distilled water, 2.5% corn steep liquor, and 5% residual frying oil, under agitation for 144 h. The biosurfactant reduced the surface tension of water from 72 to 30 mN/m and achieved a production yield of 18 g/L. It effectively emulsified 100% of burnt motor oil, forming a stable emulsion. Toxicity tests using Tenebrio molitor and Artemia salina revealed no toxic effects, with 100% survival. In cleaning tests, the biosurfactant removed 100% of oil from glass surfaces, even at concentrations below its critical micelle concentration (CMC). For oil removal from cotton fabrics, it reached efficiencies of 91, 70, and 57% at 2 CMC (0.6 g/L), 1 CMC (0.3 g/L), and 0.5 CMC (0.15 g/L), respectively. These results demonstrate the biosurfactant’s high effectiveness, safety, and environmental compatibility, highlighting its potential as a sustainable alternative to synthetic surfactants for cleaning and oil removal applications.

O setor da construção é um dos maiores geradores de emissões atmosféricas e de resíduos sólidos, o que denota a necessidade de contabilizar seus impactos ambientais na contribuição para mudanças climáticas. Uma forma de analisar esses efeitos do setor no meio ambiente é por meio da avaliação de ciclo de vida (ACV), que considera os impactos de todo o sistema de produto. Essa pesquisa propôs um método numérico para a ACV de agregado reciclado de concreto (ARCO), relacionado à pegada de carbono, baseado nos procedimentos da NBR ISO 14040, usando bases de dados e outros estudos como referências para a modelagem. Isso atende à necessidade de simplificação do processo de determinação de ACV de ARCO, tendo em vista à complexidade de dados de características do material, oferecendo uma alternativa prática para aplicações acadêmicas e industriais. No modelo, três processos principais foram adotados: a demolição da estrutura de concreto, o transporte do material e a reciclagem do agregado; e foram classificados e quantificados com base nas emissões do uso de energia elétrica e na queima de combustíveis fósseis. Assim, a equação de ACV foi modelada conforme o tamanho final do agregado e com a distância de transporte, possibilitando a obtenção de um valor de pegada de carbono. Ao final, foi possível concluir que o modelo completo foi capaz de simplificar a implementação da ACV em ARCO, obtendo consistência estatística e confiabilidade por meio de validação com estudos de referência.

The damage caused by wildfires has major impacts each year, not only on the environment but also on the economy and public health. The present study aimed at mapping the fire risk in the different areas of the municipality of Rio Verde, in the Central Brazilian state of Goiás. A number of factors that influence the occurrence of wildfires were considered in this analysis, including the orientation of the relief, the slope, population density, proximity of homes, the road network, and land cover and use. The analytical hierarchy process was used to determine the appropriate weights for each of the variables. The fire risk index was divided into five classes: water, low, moderate, high, and very high risks. Class 4 (high risk) was the most frequently recorded within the study area, followed by classes 3 (moderate risk) and 2 (low risk). Subsequently, the heat spots recorded by remote sensing were related to fire risk indices, and the framing in the classes was verified. Overall, 16.36% of the heat spots were considered low risk (class 2), while 36.29% were classified as moderate risk (class 3), and 46.72% as high risk (class 4). These findings indicate that the fire risk index provides an adequate and effective parameter for the spatial assessment of the distribution of fire events (controlled burns or wildfires) in the municipality of Rio Verde.

DOI: https://doi.org/10.46296/ig.v8i16.0298 Abstract Road infrastructure is an pillar for social and economic development, ensuring connectivity and the safe mobility of goods and people. In this context, the 30-meter-long bridge over the Quimis River represents a strategic project for the province of Manabí, following the collapse of the original bridge in 2021. This study aims to systematize the construction process of the new bridge and its access points, with a comprehensive approach that articulates the technical, environmental, and social aspects of the project. The research adopted a mixed design, both documentary and field-based. Drawings, calculation reports, technical specifications, national and international regulations, as well as photographic records and on-site observations, were collected and analyzed. Management tools such as the Gantt chart, the critical path method (CPM), and tracking diagrams were applied for planning and control. The environmental assessment was conducted using the Leopold Matrix, while the ethical analysis focused on transparency, social responsibility, and respect for the community. The results show that the project complies with current technical regulations, although it presents challenges in time control and mitigating environmental impacts. Good practices in foundations and access were also identified, as well as opportunities for improvement in social and environmental management. In conclusion, the systematization allowed for the creation of a reference academic document that strengthens professional training and contributes to the sustainable development of road infrastructure in Ecuador. Keywords: Bridge, systematization, road infrastructure, project planning, environmental impacts, ethics in civil engineering.

DOI: https://doi.org/10.46296/ig.v8i15.0273 Abstract The structural analysis and design of an earthquake-resistant university residence hall made of Guadua angustifolia Kunth (GaK), in accordance with the Ecuadorian Construction Standard NEC-SE-GUADUA, requires the integration of technical criteria ranging from material characterization to specific construction provisions. GaK characterization includes the morphological identification of culms, verification of their optimal shear age between four and six years, and compliance with conicity and cracking parameters that limit their natural variability. Furthermore, the standardized mechanical properties under a moisture content of 12% constitute the basis for defining allowable stresses and safety factors. In structural design, NEC-SE-GUADUA establishes a method for allowable stresses, with deformation control and verification of column slenderness. It also regulates the behavior of elements subjected to bending, compression, and combinations of loads, integrating shear walls as a fundamental component for lateral resistance. The application of modification coefficients adjusts the design values to the service conditions, reflecting the influence of environmental factors on the material's performance. In the construction field, the design of a university residence hall requires reinforced concrete foundations, metal culm anchors, mortar-filled bolted joints, wall panels configured as shear elements, and rigid diaphragms in floors and roofs. These criteria guarantee a continuous structural system capable of safely responding to seismic stresses typical of the Ecuadorian context. Keywords: Guadua, structural design, earthquake resistance, structural joints, university residence hall.

DOI: https://doi.org/10.46296/ig.v8i16.0291 Abstract This study presents the pedagogical validation of a didactic board designed for the teaching of electropneumatics in the Electricity Technology career, whose manufacture is exhibited to facilitate its replication in other contexts, the main objective being to evaluate its effectiveness as a training resource and explore opportunities for improvement in its educational application. To this end, progressive practices were developed aimed at strengthening competencies in the design and analysis of electropneumatic circuits, integrating both digital simulators and the direct use of the panel. The evaluation included surveys applied before and after the internships, structured with items on the Likert scale using Google forms. The results are presented in tables and graphs, which show that the use of the didactic board significantly improves the conceptual understanding and practical performance of students, by offering an immersive learning experience close to real environments. It is concluded that this resource represents an effective pedagogical strategy, with the potential to be optimized and replicated in other academic contexts, supported by the clear exposition of its manufacturing process. Keywords: electropneumatics, didactic boards, active learning, technical training.

DOI: https://doi.org/10.46296/ig.v8i15.0230 This study analyzes emotional responses to visual stimuli using the eyetracking device, which tracks eye movements and measures visual attention. Emotions influence the perception of visual information, generating different attention patterns to positive and negative stimuli. The general objective of this study is to record and analyze emotions from data obtained through eyetracking. The methodology is based on data collection, analysis and processing. A group of 40 participants was selected, who were exposed to different visual stimuli, including both positive and negative images. Five key variables were measured: Total Fixation Duration (TFD), Average Fixation Duration (ADF), Total Number of Fixations (TNF), Number of Saccades (NS) and Average Pupil Diameter during Fixations (APD). The results indicated that negative images generated a 15.3% longer average fixation duration (TPD: 175.33 ms) compared to positive images (TPD: 168.66 ms). Regarding Total Fixation Duration (TFD), positive (117.61 ms) and negative (116.07 ms) images presented comparable means, with a difference of 1.3%. The analysis of Average Pupil Diameter during Fixations (APD) revealed that positive images generated an average pupil diameter of 3.10 mm, 10.7% larger than negative images (2.80 mm). These findings support the theory that, if significant differences exist, negative emotions provoke more intense and prolonged attention, while positive emotions, although attractive, do not generate the same need for evaluation in many cases; showing that there are differences in the aforementioned variables when presenting positive and negative stimuli. This study contributes to the understanding of the emotional process in response to visual stimuli and provides a basis for future research on the relationship between emotions and visual perception. Keywords: Eyetracking, emotions, variables, pupil diameter, visual stimuli.

DOI: https://doi.org/10.46296/ig.v8i15.0231 Social media predictions allowed for an understanding of user behavior and the identification of trends, optimizing content strategies. Despite prior research across various platforms, a gap remained in the analysis of predictive models focused on Instagram. Therefore, this study aimed to conduct a systematic literature review in academic databases on models for predicting popularity on this social network. The findings revealed that organizations employed these models to improve marketing decisions, detect trends, and personalize content. It was found that individual photo posts were the most studied, while formats like reels and carousels posed analytical challenges due to the need for advanced text preprocessing techniques to enhance accuracy. Although progress has been made in developing models for other networks, studies specific to Instagram still presented limitations regarding transparency, ethics, and privacy, as well as a limited use of certain types of content for making predictions. The implications of this study are practical, as they provide marketing professionals and content creators with a comprehensive understanding of how predictive models on Instagram can be used to optimize content strategy on this platform. Keywords: predictive model, Instagram, social media, trends, gaps.