Search Results (6,241)

Background: Oral diseases such as periodontitis, dental infections, and oral dysbiosis have been increasingly associated with systemic conditions. Emerging evidence suggests a potential relationship between oral health and neurological disorders, including brain abscesses, structural brain alterations, and gliomas. However, the strength and mechanisms of these associations remain incompletely understood. Objective: To systematically review clinical, neuroimaging, genetic, and mechanistic evidence linking oral diseases with brain pathologies. Methods: A systematic literature search was conducted in PubMed, Scopus, Web of Science, and EBSCO, with complementary screening of SciELO, Redalyc, and LILACS databases. Studies evaluating associations between oral diseases (periodontitis, dental infections, caries, or oral microbiota alterations) and neurological outcomes were considered. Eligible study designs included observational clinical studies, Mendelian randomization analyses, neuroimaging studies, and experimental investigations. Seventeen studies met the inclusion criteria. Due to the substantial heterogeneity in study designs, outcomes, and effect metrics, quantitative meta-analysis was not feasible. Findings were therefore synthesized using a structured narrative approach following PRISMA guidelines. Results: Clinical studies consistently identified odontogenic infections as a relevant source of brain abscesses, frequently originating from chronic or clinically silent dental foci. Neuroimaging and genetic studies reported associations between poor oral health indicators and structural brain alterations, including reduced cortical thickness and white matter abnormalities. Experimental investigations suggested potential biological mechanisms involving microbial dissemination, systemic inflammation, and immune modulation. Virulence factors from Porphyromonas gingivalis have been shown to induce inflammatory signaling pathways and immune checkpoint activation in glioma cells. Conclusions: The current evidence suggests a possible association between oral diseases and several brain pathologies. Although causality cannot be established, the findings highlight the importance of oral health as a potentially modifiable factor relevant to neurological health. Further longitudinal and mechanistic studies are required to clarify these relationships. Full article

Building-Integrated and Building-Attached Photovoltaic (BIPV/BAPV) systems are increasingly being adopted in metropolitan areas worldwide, driven by international commitments to reduce greenhouse gas emissions and the declining cost of PV technology. A promising application involves the vertical integration of PV panels into building facades, which offers architectural and energy benefits, particularly in urban environments with limited roof space. This study experimentally evaluates the energy behavior of 12 vertically mounted 5 W PV panels (model SP005P) installed on university buildings in Ibarra, Ecuador, across four azimuth orientations (−135° SE, −45° NE, 45° NW, 135° SW). A continuous 8-month monitoring campaign was conducted using a custom-designed Arduino-based data logger, validated with multimeter measurements (error < 5%). The dataset was used to develop MATLAB version 2025b forecasting models based on Sum-of-Sine functions, achieving R² values between 0.83 and 0.98 and RMSE values between 0.024 and 0.082 W. The 45° (NW) orientation achieved the highest annual energy yield of 48% STC, reaching up to ≈440 kWh/kWp in the best-performing facade, while 135° (SW) also exhibited favorable performance compared with the northeast and southeast orientations. These findings provide significant evidence for facade-integrated PV design in equatorial latitudes, offering performance benchmarks and validated forecasting tools that can support architectural planning, BIPV feasibility analysis, and urban solar-energy strategies in regions with similar conditions. Full article

We investigated the effect of film thickness d on the acoustic response of titanium dioxide (TiO₂) layers deposited on Ti, SiO₂, Al₂O₃, and Si substrates. For each TiO₂ thickness–substrate pair, we computed reflection coefficients and acoustic signatures under normal operating conditions of a conventional scanning acoustic microscope, then deduced the Rayleigh-wave velocity V_R from spectral analysis of the oscillatory layer–substrate signatures. As d increased, V_R either rose or fell, depending on the layer/substrate pair, and eventually approached a saturation value. For TiO₂/SiO₂ and TiO₂/Ti, V_R increased from those of the bare substrates (SiO₂: 3415 m/s; Ti: 2965 m/s) toward 3830 m·s⁻¹, the bulk TiO₂ value. For TiO₂/Al₂O₃ and TiO₂/Si, V_R decreased from the substrate values (Al₂O₃: 5700 m/s; Si: 4712 m/s) toward the same TiO₂ saturation. These dispersion trends are consistent with stiffening (V_R (TiO₂) > V_R (Substrate)) or loading (V_R (TiO₂) < V_R (Substrate)) effects. The resulting V_R–d dispersion charts provide theoretical reference trends relating thickness and Rayleigh-wave velocity for the idealized TiO₂/substrate systems considered here. Full article

Nutrient inputs from human activities, such as agriculture and sewage discharge, influence algal blooms in water bodies. In Ecuador, the Daule River receives wastewater discharges. In addition, poor agricultural practices, including the unsuitable use of fertilisers in combination with soil erosion and surface runoff processes, increase the nutrient load to the river. Considering this, the objective of this study was to evaluate environmental and biological variables using statistical analysis to identify the parameters that influence algal blooms in the main stem of the Daule River. The methodology consisted of two phases: (i) data collection, including water sampling and laboratory work for the analysis of nutrients and phytoplankton, and (ii) statistical analysis, which includes univariate, bivariate, inferential and multivariate analysis (STATICO technique). The results showed that pH and dissolved oxygen were the main drivers of diatoms (Polymyxus coronalis and Aulacoseira granulate) and the charophyte Mougeotia sp. Similarly, ammonium-N was the main driver of the diatom Ulnaria ulna and the cyanobacteria Planktothrix cf. agardhii. The outcomes of this study identified the main environmental variables driving blooms of the five most abundant species, providing a basis for the development of ecological models in the context of land use and climate change. Full article

Generative AI is reshaping university teaching and creating tension around authority, evidence, and accountability when decisions are made using algorithms. From a student perspective, this study constructed a typology of distributed teacher–AI agency (TAI) and examined the discursive mechanisms that produce the illusion of teacher autonomy. A non-experimental, cross-sectional, explanatory study was conducted: a lexicometric analysis of the ALCESTE (IRAMUTEQ) questionnaire, using open-ended responses from 3120 students (Mexico, n = 2051; Ecuador, n = 1069), segmented into 1077 units, and analyzed using positioning theory. Co-agency was operationalized using Teacher Agency (A), Delegation to AI (D), Governance (G: disclosure, criteria, verification), and the Illusion Index (II = A/(D + G + 1)). Three configurations emerged: Immediate Customizer (28.8%) with very high A and minimal D/G (II = 25.4); Technological Literacy Facilitator (27.3%) with visible delegation and safeguards (II ≈ 2.0); and Operational Optimizer (43.9%) oriented toward accelerating tasks with moderate governance (II ≈ 2.7). The illusion was associated with the agentive erasure of AI and a rhetoric of immediacy/efficiency that replaced verifiable criteria. These findings transform the student voice into a criteria-based diagnostic tool for strengthening traceability, minimal verification, and responsible orchestration of AI in higher education. Full article

Based on data from 208 students involved in entrepreneurship studies at Tecnológico de Monterrey, Mexico, this paper examines whether prior experience with AI, expectations, gender, and age reinforce future AI use. To achieve this objective, we applied binary logistic regression with random oversampling to balance the dataset. We complemented it with additional model performance metrics, including the confusion matrix, sensitivity, specificity, and area under the ROC curve. The results show that prior experience with AI, age-related technology use, and positive expectations regarding AI are associated with a higher likelihood of reinforcing future AI use. In terms of gender, the results indicate a gender gap favoring women, who are more likely to use AI when they perceive greater utility and confidence, as well as a stronger desire to succeed. Full article

Background: Rapidly progressive glomerulonephritis (RPGN) is a severe nephrological emergency, frequently secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. In older adults, the coexistence of comorbidities and monoclonal gammopathy of undetermined significance (MGUS) makes it difficult to distinguish between ANCA vasculitis and monoclonal gammopathy of renal significance (MGRS), which differ in prognosis and treatment. The coexistence of PR3-ANCA-associated vasculitis and MGUS is uncommon and sparsely documented. Case Presentation: A 72-year-old woman with hypertension and type 2 diabetes presented with acute deterioration and rapidly progressive renal failure, requiring hemodialysis. She had subnephrotic proteinuria, hematuria, and an active urinary sediment. The autoimmune workup showed ANCA negativity using immunofluorescence, but PR3-ANCA positivity using ELISA. Hematologic characterization documented an IgG kappa monoclonal spike; no bone lesions, amyloidosis, or criteria for multiple myeloma were found; and the patient was classified as MGUS. Renal biopsy revealed necrotizing extracapillary pauci-immune glomerulonephritis with cellular and fibrocellular crescents and no monoclonal deposits, consistent with PR3-ANCA vasculitis. Induction therapy with methylprednisolone pulses and oral prednisone was initiated; cyclophosphamide was not administered because of catheter-associated Staphylococcus aureus bacteremia and upper gastrointestinal bleeding complicated by disseminated intravascular coagulation. The patient died on day 25 due to infectious and hemorrhagic complications. Conclusions: This case provides additional documentation of an uncommon overlap between PR3-ANCA-associated vasculitis and MGUS in a Latin American patient and highlights the role of renal biopsy in distinguishing MGRS from pauci-immune vasculitis in the presence of paraproteinemia. It also underscores the need to tailor immunosuppression in frail older adults, balancing disease control against the risk of severe infection. Full article

The leishmaniases are a group of neglected tropical diseases caused by kinetoplastid protozoa of the genus Leishmania, transmitted by phlebotomine sandflies. In the absence of a human vaccine, current chemotherapeutic options remain suboptimal due to limited target selectivity, high cost, restricted availability in endemic low-resource regions, and escalating parasite resistance. This review highlights recent advances in rational drug design directed at the kinetoplast—a distinctive mitochondrial organelle critical for parasite viability. Different targets (e.g., kDNA, G-quadruplex, topoisomerases) and innovative approaches employing mitochondrion-targeted small molecules are discussed, as well as ligand-functionalized nanoparticle delivery systems that can transport bioactive agents to the parasite’s mitochondrial microenvironment. These strategies highlight the kinetoplast’s strong translational relevance as a selective antileishmanial target. By exploiting its unique molecular machinery, these strategies may offer improved parasite selectivity, although potential mitochondrial liabilities in host cells must be carefully evaluated. Full article

Scholarly knowledge graphs integrate bibliographic records from heterogeneous sources and therefore require controlled, auditable deduplication. This paper presents OntoDup, an ontology-driven approach that models entity matching as a governed decision process: Matching outcomes are recorded as reified assertions enriched with governance state, evidence, provenance and operational metadata, while a separate operational view is exposed through policy-driven materialization of consumable identity links. We evaluate OntoDup on the DBLP-ACM and DBLP-Scholar benchmarks under two regimes: (i) a pre-blocked setting using the benchmark candidate lists to compare matching methods under a fixed candidate set, and (ii) an end-to-end setting that generates candidates from the graph with DeepBlocker and applies governed triage and materialization. We report operational precision/recall/$F_1$ computed directly on the graph via SPARQL aggregations, characterize governance workload through state distributions, and quantify inference cost for LLM-based matchers via token and latency metadata attached to assertions. For end-to-end evaluation, we anchor operational links against a full positive reference encoded as idealized validations derived from the benchmark labels, enabling analysis of missed positives in terms of governance status and materialization policy. The experiments show that OntoDup enables evaluation at the level of consumable identity links, review workload, and inference cost, revealing operational trade-offs that are not visible from pairwise matching metrics alone. Full article

This study develops a multiregional forecasting framework for road traffic accidents in Ecuador, addressing a critical limitation in existing predictive approaches that rely predominantly on point error metrics without validating the statistical assumptions underlying forecast uncertainty. Although the analysis is conducted at the provincial level, the spatial dimension is used primarily for cross-regional comparison and risk classification rather than for explicit spatial interaction modeling. Using a dataset of 27,648 monthly observations covering all 24 provinces from 2014 to 2025, the study applies the Prophet model within a Design Science Research paradigm and a CRISP-DM implementation cycle. Separate provincial models are estimated with a 24-month forecasting horizon, and methodological rigor is ensured through systematic residual diagnostics using the Shapiro–Wilk test for normality and the Ljung–Box test for temporal independence. Empirical results indicate that the Prophet-based artifact outperforms a naïve seasonal benchmark in 70.8% of the provinces, demonstrating excellent predictive accuracy in structurally stable regions such as Tungurahua (MAPE = 10.9%). At the same time, the framework enables the identification of critical emerging risks in provinces such as Santo Domingo and Cotopaxi, where projected increases exceed 49% despite acceptable point forecasts. The findings confirm that point accuracy alone does not guarantee the validity of confidence intervals and that residual validation is essential for trustworthy uncertainty quantification. Overall, the proposed approach provides a robust foundation for a predictive surveillance system capable of supporting differentiated, evidence-based road safety policies in territorially heterogeneous contexts. Full article

Urban pedestrianization has become a widely adopted strategy to promote sustainable mobility, improve urban livability, and enhance the quality of public space. Despite its potential benefits, pedestrianization interventions often generate heterogeneous perceptions among different user groups, which may influence their long-term acceptance. This study analyzes citizen perceptions of an urban pedestrianization intervention implemented in the city of Loja, Ecuador, considering residents, business owners or employees, and pedestrians or visitors. A structured survey was conducted, and the collected data were analyzed using exploratory analytical techniques, including rescaled single-item indices, user segmentation, and Spearman correlation analysis to identify patterns and relationships among variables. The results reveal significant associations between socio-demographic characteristics, user type, and acceptance of permanent pedestrianization, as well as differentiated patterns of urban experience. These findings provide empirical evidence to support decision-making in urban mobility policies and contribute to the academic discussion on pedestrianization in intermediate Latin American cities. Full article

Context-aware mobile applications operating in environments with intermittent or unreliable connectivity must support offline-first behavior while preserving consistent decision-making and timely synchronization. Traditional cloud-centric architectures often fail to provide adequate availability, responsiveness, and reliable context reasoning under such conditions. This paper presents CAMS-F Edge DTN, an edge-centric runtime designed to support offline-first context-aware applications operating under intermittent connectivity. The proposed approach extends the CAMS domain-specific language (DSL) with declarative policies for semantic reconciliation, opportunistic synchronization, and context-aware conflict resolution. The runtime integrates Conflict-Free Replicated Data Types (CRDTs), opportunistic communication channels such as Bluetooth and Wi-Fi Direct, and MQTT-SN messaging to enable robust data exchange across mobile, vehicular, and edge nodes. CAMS F-Edge DTN supports offline-first execution by allowing applications to evaluate contextual rules locally and reconcile distributed state asynchronously when connectivity becomes available. The approach is evaluated through controlled experiments and case studies in rural logistics and healthcare distribution scenarios. The experimental results show that the proposed architecture maintains 96–99% operational availability under intermittent connectivity and up to 100% availability during fully offline operation, while achieving low-latency local reasoning (<10 ms median latency) and deterministic state convergence through CRDT-based synchronization mechanisms. Full article

Background: Obstructive sleep apnea (OSA) is a prevalent sleep-related breathing disorder associated with multiple systemic comorbidities. Gastroesophageal reflux disease (GERD) has been frequently reported among patients with OSA; however, the magnitude of this association remains uncertain. Objective: To systematically evaluate and quantify the association between obstructive sleep apnea and gastroesophageal reflux disease in adult populations. Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines and a protocol registered in PROSPERO (CRD420261278563). Electronic searches were performed in PubMed/MEDLINE, Scopus, Web of Science, and Embase. Observational studies assessing the association between OSA and GERD were included. Risk of bias was assessed using the Newcastle–Ottawa Scale. A random-effects meta-analysis was performed to pool odds ratios (ORs) with 95% confidence intervals (CIs). Results: Six observational studies were included in the quantitative synthesis. The pooled analysis demonstrated a statistically significant association between obstructive sleep apnea and gastroesophageal reflux disease, with a combined OR of 1.96. Moderate heterogeneity was observed among studies (I² = 65%). No substantial evidence of publication bias was identified based on funnel plot assessment. Conclusions: These findings suggest that obstructive sleep apnea is associated with nearly two-fold increased odds of gastroesophageal reflux disease and support increased clinical awareness rather than formal screening recommendations. Full article

University mobility in medium-sized cities faces increasing challenges arising from traffic congestion, urban sprawl, and the limited availability of sustainable transport options. In this context, the bicycle represents an efficient and environmentally low-impact alternative, provided that safe and connected infrastructure exists to facilitate its adoption. This study assesses the potential for bicycle use in the Andean city of Loja, Ecuador, taking as a case study the university community of the Universidad Técnica Particular de Loja (UTPL). Geographic Information Systems (GIS) tools, origin–destination (OD) matrices, and logistic models were integrated to analyze the relationship between three key variables: terrain slope, minimum travel time, and the percentage of protected cycling infrastructure. The results show that protected cycling infrastructure shows the strongest positive association with the modeled probability of use, while slopes greater than 15% and trips longer than twenty minutes are associated with lower modeled probabilities. The geospatial analysis identified priority corridors where improvements in cycling protection would yield higher modeled modal returns. It is concluded that strengthening cycling connectivity and the continuity of protected routes may inform scenario-based planning to support active university mobility, offering a replicable framework for medium-sized cities with similar topographic conditions. Full article

Chile stands out for its renewable energy resources and its commitment to developing green hydrogen. However, achieving cost parity with gray hydrogen remains an obstacle, mainly due to high capital costs and sensitivity to scale. This study assesses the technical and economic feasibility of green hydrogen production, using five different plants located in the Magallanes region in the south of the country as a reference. The model integrates a detailed framework of wind generation, PEM electrolysis, compression, and high-pressure storage subsystems, as well as a stochastic economic layer that combines the CAPEX, NPV, and LCOH assessments using Monte Carlo simulations. It also incorporates real-world capacity distributions and probabilistic fluctuations in systems. A sensitivity analysis confirms production scale as the main factor affecting profitability, with a break-even threshold of 0.5 MW. The results show that the LCOH decreases from 7.1 USD to 3.4 USD/kgH₂ as capacity increases. The analysis reveals that only 23.88% of small-scale configurations yield positive NPV, underscoring the need for scaling to achieve economic viability. Full article