Produção Científica e Didática

Produção científica recente

Framework to Detect Adulterated Honey Using Hyperspectral Imaging and Machine Learning

Artículos y libros

Honey is a natural product renowned for its nutritional and medicinal properties. However, the increasing market demand in Pakistan has led to frequent instances of adulterated and fraudulent honey. Conventional detection methods are widely used but are often ineffective in accurately identifying adulteration. This study proposes a novel approach to detecting adulteration in honey, specifically the mixing of sugar, using machine learning (ML) techniques in conjunction with hyperspectral imaging (HSI). By leveraging HSI, we capture distinct spectral features of both pure and adulterated honey. These spectral features are processed and analyzed using ML algorithms trained on a dataset comprising pure and mixed honey samples. Experiments involve binary, as well as, multiclass (5 classes) honey samples with different levels of adulteration. In addition, data balancing is also carried out using synthetic minority oversampling technique (SMOTE). The results prove the proposed approach to be efficient in detecting adulteration across various honey varieties, with linear regression achieved 99.9% while support vector machine and multilayer perceptron obtaining a 98.7% accuracy for binary class. For the multiple classes of honey, the multilayer perceptron shows a 96.67% accuracy outperforming the remaining ML and deep learning models. Among the deep learning models, the convolutional neural network (CNN) achieved the best performance with an accuracy of 94.67% after applying the SMOTE × 3 (three times of over samples of original samples of each class) data balancing strategy, whereas recurrent neural network (RNN), long short-term memory (LSTM), and gated recurrent unit (GRU) models showed comparatively lower performance.

Leer más

Cryptocurrency Market Trends: A Machine Learning-Driven Time Series Forecasting with Twitter Sentiment Integration

Artículos y libros

Accurate forecasting of cryptocurrency prices remains an open challenge because classical statistical models cannot capture the non-linear, sentiment-driven dynamics of these markets. This study compares three hybrid deep learning architectures—VAR-LSTM, XGBoost-LSTM, and CNN-LSTM—to determine which best forecasts Bitcoin (BTC), Ethereum (ETH), and Dogecoin (DOGE) closing prices, and to quantify the marginal predictive value of Twitter sentiment integration. Six years of hourly OHLCV data (2017–2023) are augmented with VADER-scored Twitter sentiment polarity. Each model is formulated mathematically, implemented with documented hyperparameters (epochs, dropout, units;), and trained for one-step-ahead next-hour price prediction. Performance is measured by RMSE, MAE, MAPE, R 2 , and Directional Accuracy (DA) across five random seeds, with paired Wilcoxon significance tests. XGBoost-LSTM achieves the best performance (RMSE = 81.547, R 2 = 0.9254, DA = 80.0%), outperforming all nine literature baselines. Removing Twitter sentiment degrades DA by 14.3 percentage points ( p < 0.01 ), confirming that social media signals carry independent predictive information. Hybrid architectures consistently outperform single-model baselines; XGBoost-LSTM offers the best accuracy-to-compute ratio. VADER-enriched Twitter sentiment is a significant predictor beyond price history. Limitations include reliance on a single sentiment platform and a training window that predates several structural market events

Leer más

Rethinking legal protection against gender-based and domestic violence in Angola: human rights and governance

Artículos y libros

Gender-based and domestic violence remain among the most significant challenges to the protection of women's human rights in Angola. This study aimed to analyse the conceptual evolution of gender-based violence, examine the applicable national and international legal framework, and assess the institutional challenges affecting the effectiveness of the protection system from a socio-legal perspective. A qualitative research design was adopted through a legal-documentary review of scientific literature, national legislation, international human rights instruments, and institutional documents published mainly between 2020 and 2026. The findings reveal important legal advances through the Constitution of Angola, Law No. 25/11 on Domestic Violence, and international human rights instruments that strengthen the legal protection of women. However, significant challenges remain regarding effective access to justice, institutional coordination, prevention strategies, and the implementation of public policies. As its main contribution, the study proposes a socio-legal model structured around five strategic dimensions—prevention, comprehensive protection, access to justice, institutional coordination, and comprehensive reparation—to strengthen the State's response and improve the effective protection of women's rights in Angola.

Leer más

Artificial intelligence-based clinical decision support systems in neurophysiology: conceptual framework, design criteria, and ethical considerations

Artículos y libros

Diagnosis in neurophysiology using visual evoked potentials (VEP) for multiple sclerosis and optic neuropathies remains specialist-dependent and subject to variability. Artificial intelligence (AI) offers transformative potential, but its responsible implementation is hindered by algorithmic metrics. This paper develops a conceptual framework for AI-based clinical decision support systems (CDSS) in neurophysiology, structured around three integrated dimensions: CDSS typology and foundations, responsible design criteria, and ethical-regulatory considerations. Six architectural principles are proposed: transparency, clinical anchoring in validated criteria (ISCEV 2023), preservation of physician judgment, false-alarm minimization, reproducibility, and interoperability, applicable to any system in the field. The framework is illustrated through an EEG‑VEP system on the VEPCON dataset, integrating automated classification, clinical hierarchy over statistical thresholds, and a dashboard with an explicit ethical disclaimer. The responsible development of CDSS in neurophysiology demands a systemic approach that integrates clinical evidence, operational design, and medical device regulation, ensuring their role as support rather than as a substitute for clinical judgment.

Leer más

Parental Decision-Related Factors Are Associated with Discretionary Ultra-Processed Food Consumption Among Children and Adolescents Living in the Mediterranean Area

Artículos y libros

Background/Objectives: Nutrition during childhood and adolescence is a key determinant of long-term health, influencing metabolic homeostasis, neurocognitive development, and immune system maturation. Globalization and technological advances have reshaped food production and consumption, increasing the availability of ultra-processed foods (UPF) of low nutritional quality. This study aimed to investigate the relationship between parental factors, namely food literacy, perceived barriers and enablers, dietary attitudes, and healthy eating behaviors, and the consumption of discretionary UPF among children and adolescents living in 5 Mediterranean countries. Methods: This cross-sectional study was based on a survey completed by 2011 parents of children and adolescents aged 6–17 years from 5 Mediterranean countries, who reported on their children’s dietary and lifestyle habits. Adherence to the Mediterranean diet was assessed through the KIDMED index. Parental food literacy was measured using the Short Food Literacy Questionnaire (SFLQ). Perceived barriers and enablers were assessed based on the Theory of Planned Behavior, and parents’ attitudes toward their child’s diet were evaluated using the Healthy-Eating Attitudes Questionnaire (HEAQ). Finally, the Theory of Internet Use Related to Health (TIUH) questionnaire was used to assess parents’ tendencies related to health information use online. Results: Higher perceived barriers and enablers were significantly associated with lower discretionary UPF consumption across all models. Parental food literacy (SFLQ) showed a positive association with discretionary UPF consumption, remaining significant in the fully adjusted model, although with reduced magnitude. Healthy-eating attitudes (HEAQ) were initially positively associated with discretionary UPF intake but lost statistical significance after full adjustment. Regarding health-related internet use (TIUH), the Health Information dimension showed a strong positive association with discretionary UPF consumption, while other dimensions (Consciousness and Beliefs) showed inconsistent and non-significant associations in the fully adjusted model. Conclusions: Children’s consumption of discretionary UPF is shaped by several interrelated factors, such as family environment, eating patterns, and parents’ perceptions, rather than solely by knowledge or attitudes.

Leer más