Search Results (234)

Background: Minimally invasive liver surgery has continuously developed with the advent of robotic systems that could present some advantages regarding dexterity and visualization. Single-port robotic devices have been introduced more recently in order to minimize the invasiveness of surgery. Unfortunately, scientific literature on this topic is still poor. This pilot feasibility study aimed to assess the technical applicability and short-term outcomes of single-port robotic liver resection. Methods: The study was designed as a retrospective analysis of 11 consecutive patients treated with single-port robotic liver resection. All interventions were performed in order to treat lesions localized in the anterolateral segments of the liver. All preoperative, intraoperative, and postoperative data were collected retrospectively and considered for the analysis. Cirrhotic patients were graded according to the Child–Pugh score. Results: The median age was 67 years (IQR 41–78), and 63.6% of the patients were women. There was cirrhosis in 27.3% of the cases, and all cases were categorized as Child–Pugh class A. Neoadjuvant chemotherapy was not administered in any of the patients. All procedures were considered Tampa grade II. The median operation time was 190 min (IQR 70–320), and the median blood loss was 50 mL (IQR 0–300). Pedicle clamping was done in 36.4% of the cases. An additional assistant trocar was needed in 45.4% of the procedures. In total, two anatomical and nine non-anatomical resections were done. There were no postoperative complications, reinterventions, and 90-day readmissions. The median length of hospitalization was 2 days (IQR 1–3). The postoperative pain was minimal, with a median VAS and NRS score of 0 on postoperative days 0 and 1. Analgesic treatment was ceased on postoperative day 1, and the median time to first flatus was 1 day in all patients. Conclusions: Single-port robotic liver resection seems to be technically possible in selected patients with intermediate-difficulty lesions in anterolateral segments. Additional research is necessary to establish its role in minimally invasive liver surgery. Full article

Digital Elevation Models (DEMs) are essential tools for terrain analysis. However, their selection often focuses on spatial resolution or overall vertical accuracy, overlooking aspects such as geometric consistency or fitness for specific applications. This misalignment between DEM’s capabilities and study requirements can lead to inaccurate interpretations, undermining the reliability of the results. To address this, we assessed the accuracy of seven freely available global DEMs (SRTM, ASTER, ALOS, Copernicus DEM, MERIT DEM, NASADEM, and FABDEM) against a 1 m LiDAR reference in a coastal region of El Salvador. Our workflow combined traditional metrics (RMSE, MAE, ME) with spatial error visualizations (histograms and heatmaps) and introduced the Spatial Error Robustness Index (SERI) with RMSE/SD ratio to jointly quantify error magnitude and variability. Elevation and slope were selected for DEM–LiDAR comparisons. Results show that all DEMs systematically overestimate elevation, with slope errors amplified by scale discrepancies. FABDEM achieved the highest elevation accuracy across coastal and tectonic landscapes, ALOS the lowest slope RMSE overall and Copernicus performed best in coastal zones; DEM performance depends on terrain and parameters. The SERI and RMSE/SD ratio, combined with spatial visualizations, revealed systematic error patterns and improved geomorphic coherence interpretation. Full article

Background/Objective: Postpartum hemorrhage is a leading cause of maternal morbidity and mortality, particularly among high-risk women undergoing cesarean section. This systematic review and meta-analysis evaluated the efficacy and safety of prophylactic tranexamic acid in high-risk cesarean sections. Methods: A systematic review and meta-analysis of randomized controlled trials was conducted. Risk of bias was assessed using RoB 2.0 and certainty of evidence was evaluated with GRADE. Random-effects meta-analyses, subgroup analyses and sensitivity analyses were performed. PROSPERO: CRD420251087054. Results: Nine randomized controlled trials involving 1776 participants were included. Tranexamic acid reduced total blood loss (MD −300.78; 95% CI −459.78 to −157.77), with greater efficacy when administered 15–20 min before incision (SMD −0.61; 95% CI −0.82 to −0.39). It also reduced intraoperative blood loss (MD −256.71 mL; 95% CI −375.04 to −138.39), blood loss >1000 mL (RR 0.24; 95% CI 0.14 to 0.41), additional uterotonics (RR 0.37; 95% CI 0.24 to 0.58), blood transfusions (RR 0.30; 95% CI 0.22 to 0.40), and complementary surgical interventions (RR 0.35; 95% CI 0.16 to 0.78). Conclusions: Prophylactic tranexamic acid may reduce blood loss in high-risk cesarean deliveries, particularly when administered 15–20 min before skin incision. It may decrease total and intraoperative blood loss and blood loss exceeding 1000 mL. It also likely reduces the postoperative decline in hemoglobin, the need for additional uterotonics, blood transfusions, and complementary surgical interventions; however, its effect on hematocrit remains uncertain. Full article

Background: Breast cancer is the most common cancer in women both in Peru and worldwide. Although mammography remains the standard for early detection, its effectiveness may be limited by unequal access to this technology. In this context, liquid biopsy emerges as a minimally invasive complementary technique that allows the identification of circulating biomarkers, such as microRNAs (miRNAs), whose differential expression has been associated with breast cancer. Methods: The present study evaluated the diagnostic potential of cell-free circulating miRNAs for the early detection of breast cancer. In the screening phase, seven candidate miRNAs were quantified by qPCR in plasma from patients with early-stage breast cancer and healthy controls. In the validation phase, miR-191, miR-182, miR-335, and miR-125b were analyzed in an independent cohort of 30 untreated patients to evaluate their diagnostic performance. Results: miR-125b and miR-335 showed the best individual diagnostic performance, with AUCs of 0.81 and 0.78, respectively, and presented a significant moderate correlation (ρ = 0.608; p < 0.05), supporting their biological consistency and potential as complementary biomarkers. The multivariable binary logistic regression model that integrated both miRNAs showed a moderate improvement in discriminatory ability; however, the expanded multivariable model that incorporated the four validated miRNAs achieved an AUC of 0.91, with a sensitivity of 92% and a specificity of 90%. Conclusions: The panel composed of miR-191, miR-182, miR-335, and miR-125b represents a promising set of circulating biomarkers for the early detection of breast cancer. Full article

Disabilities of the lower extremities significantly affect a person’s ability to perform activities of daily living. Many people have been affected by this type of disability due to birth disease or injury from accidents, strokes or even old age. The technical aids used in this type of disability are very basic, and rehabilitation is mainly performed by therapists. Rehabilitation consists of repetitions of exercises with normal movements that must be performed for prolonged periods of time. On the other hand, therapists, having to support the weight of the patient, tend to get injured. This paper introduces the design and modeling a robotic device intended to assist the therapist in the rehabilitation of sit-to-stand (STS) and walking movements, focusing primarily on the technical aspects of the system. The robot is designed to safely support the user’s weight and guide the user with appropriate movements according to the usual biomechanics of STS. This paper presents the solution of the inverse kinematic modeling of both the position and velocity of the robot mechanism, as well as the dynamic analysis. A series of simulations is conducted to evaluate the performance of the proposed mechanical architecture during the STS task, providing quantitative information on the system dynamics and the interaction forces between the user and the robot. The mathematical model was employed in the design of a prototype intended for children aged 8–12 years, capable of supporting up to 50 kg and providing a vertical motion range of 20–90 cm. The main structural elements of the robot, its control architecture, and its operation during the execution of the STS task are described. Finally, the conclusions of this work are discussed, and future work derived from this research is outlined. Full article

The large-scale mobility restrictions implemented worldwide in response to the COVID-19 (SARS-CoV-2) pandemic led to short-term reductions in anthropogenic emissions, providing an opportunity to explore atmospheric pollutant responses to large-scale changes in human activity and mobility patterns. Although numerous studies have reported air quality improvements during lockdowns, most rely on ground-based monitoring networks and focus on developed regions, leaving gaps in less-studied areas such as Central America. This study evaluates spatiotemporal changes in tropospheric nitrogen dioxide (NO₂) across Central America before, during, and after COVID-19 lockdowns using satellite-based remote sensing. High-resolution NO₂ vertical column density (VCD) data from the TROPOMI instrument onboard Sentinel-5P were processed using Google Earth Engine. Percentage variations were calculated using the March–May 2020 lockdown period as a reference within the 2019–2021 analysis period. Results indicate reductions in NO₂ across several high-density departments, particularly in Guatemala, El Salvador, and Honduras, with decreases of 20–30% and localized negative variations below −40%. In contrast, Nicaragua exhibited comparatively limited changes, while a gradual recovery in NO₂ concentrations was observed during 2021. The observed patterns suggest a potential association between NO₂ variability and changes in anthropogenic activity during the COVID-19 period, while also highlighting the importance of considering meteorological influences in regional atmospheric assessments. The results further demonstrate the potential of cloud-based Earth observation platforms for atmospheric monitoring in data-scarce tropical regions. Full article

Robust tsunami casualty estimation is vital for Peru’s central coast. While static maps ignore evacuation dynamics, precise agent-based models (ABMs) are often too computationally demanding for rapid screening. To bridge this gap, we propose an efficient geospatial workflow coupling TUNAMI-N2 simulations with shortest-path routing. Evaluating four subduction scenarios across Chorrillos and Villa El Salvador, the model tracks census-block evacuation progress. By intersecting evacuation trajectories with tsunami arrival times, casualties are calculated using empirical depth-dependent fragility functions. Results highlight that delayed reaction times significantly increase mortality. Furthermore, a counterintuitive dynamic emerges in spatially constrained corridors lacking vertical evacuation: higher walking speeds can paradoxically increase fatalities by advancing evacuees into deeper inundation zones before being overtaken. This highlights that behavioral preparedness must be coupled with structural urban interventions. Ultimately, our scalable approach enables DRR (Disaster Risk Reduction) managers to rapidly map mortality hotspots and prioritize critical infrastructure improvements in highly exposed coastal zones. Full article

This study presents the development and validation of a simulation-calibrated kinematic formulation for a three-wheeled symmetric pipeline inspection robot operating under cylindrical confinement. The proposed model integrates analytical implementation in MATLAB 2023b with multibody simulation in SolidWorks 2023 to identify semi-empirical correction terms that improve motion prediction under straight and curved pipe conditions. The formulation incorporates curvature-dependent and asymmetry-related effects derived from structured simulation datasets, ensuring consistency between analytical predictions and simulated behavior within the evaluated operating range. Quantitative comparison using statistical indicators demonstrates strong agreement between both approaches, with MAE values of 0.0547 for linear velocity and 13.96 for displacement, RMSE values of 0.0681 and 19.0401, and coefficients of determination of $R^2=0.9997$ and $R^2=0.9476$, respectively. Slightly larger deviations are observed at higher rotational speeds. The results provide a consistent analytical representation of the robot’s motion under the studied geometric constraints and establish a basis for future experimental validation and control-oriented extensions in confined pipeline environments. Full article

Vanilla (Vanilla planifolia Jacks. ex Andrews) is a tropical orchid of high economic value, with an annual production of 8000 to 10,000 t and a market exceeding 800 million USD in over 40 countries. In vitro propagation has strengthened the innovation, production, and conservation of this species. Bibliometrics, as a quantitative approach, systematically examines the patterns, dynamics, and evolutionary trends of scientific production. A systematic search was conducted in Scopus and Web of Science until December 2025, using the terms “vanilla” and “micropropagation”. A total of 53 documents were identified in Scopus (1997–2025) and 39 in Web of Science (2000–2025). The evaluated indicators included: year of publication, country of origin, language, areas, main categories, document typology, authorship, and keyword distribution. VOSviewer was used for keyword analysis to identify author collaboration networks and emerging trends. The years with the most information were 2024 and 2025, with Mexico and India standing out prominently. The main thematic areas were Agricultural and Biological Sciences, and the role of researcher Ramírez-Mosqueda was highlighted. The keywords with the highest correlation and impact were bioreactors, vanillin, and cryopreservation. This bibliometric study provides a comprehensive perspective on scientific production related to vanilla micropropagation. The results highlight the multidisciplinary nature of biotechnology applied to this crop, integrating contributions from various areas of knowledge for the benefit of the main actors in the value chain. Full article

Natural products from plants have played an important role in cancer and neurodegenerative diseases. In this context, the root bark of Maytenus chiapensis (Celastraceae) was investigated to examine its chemical constituents and potential biological activities. Chromatographic separation of the root bark extract yielded a new Diels–Alder adduct (morenine) formed by a triterpenophenolic moiety derived from tingenone and a bicyclic guaiane-type sesquiterpene linked through a 1,4-dioxane bridge. In addition, eight previously reported Diels–Alder adducts—retusonine and cheiloclines A–D and F–H—were isolated, together with their biosynthetic precursors, the quinone-methide triterpenoids (QMTs) pristimerin and tingenone. Structural elucidation was achieved through detailed 1D and 2D NMR spectroscopic analyses. The adducts were tested for cytotoxicity against six cancer cell lines (A549, SW1573, MIA PaCa-2, T-47D, HeLa, and WiDr cell lines), showing moderate-to-low activity compared with their precursors. Continuous live cell imaging identified apoptosis and vacuole formation as the main modes of action of pristimerin in SW1573 cells. Moreover, acetylcholinesterase inhibition assays revealed that cheiloclines B–D, F, and H exhibited up to 50% inhibition. These findings reinforce the potential of Celastraceae species as a source of unique and complex compounds and enhance our understanding of their therapeutic potential. Full article

This study evaluated the impact of incorporating citrus pulp (CiP) into the rations of high-producing dairy cows under tropical conditions. Eighteen lactating dairy cows were assigned to two dietary treatments: corn meal (CM) or CiP as the main energy source. Dairy cows were allocated to a crossover design comprising two 21-day periods. The rations were formulated to be isocaloric and isonitrogenous. Replacing CM with CiP reduced the intakes of dry matter (19.9 vs. 19.5 kg/d), organic matter (17.9 vs. 17.4 kg/d), digestible organic matter (12.3 vs. 11.7 kg/d), and crude protein (3.43 vs. 3.35 kg/d), while increasing neutral detergent fibre intake (7.39 vs. 7.63 kg/d). Apparent total tract digestibility decreased for all nutrients, including DM, OM, CP, NDF, and ADF, when CiP replaced CM. Milk production was lower in cows fed CiP than in those fed CM (23.7 vs. 22.7 kg/d), although milk feed efficiency (milk/DMI) was not different. An economic analysis showed that cows fed CM had higher milk gross income and income over feed cost. These results suggest that the partial replacement (60%) of CM with CiP may negatively affect feed intake, nutrient digestibility, milk production, and profitability in dairy cows in tropical regions. Full article

West Nile virus (WNV) is a mosquito-borne flavivirus with one of the widest global distributions. Since its discovery in Uganda in 1937, it has become a major zoonotic pathogen, and after its introduction into the United States in 1999, it spread rapidly across the Americas, becoming the leading cause of neuroinvasive arboviral disease. Its expansion illustrates a remarkable ecological adaptability, further intensified by climate change. In Latin America and the Caribbean, WNV circulation has been consistently documented in birds, horses, and mosquitoes; however, confirmed human cases remain disproportionately scarce compared with North America and Europe. Reports include sporadic human cases in Brazil (>100 since 2014), Mexico (~13), Argentina (2006–2007), Puerto Rico (2007), Nicaragua, and Haiti, while animal and vector evidence extends to Guatemala, El Salvador, Belize, Costa Rica, Bolivia, Paraguay, Colombia, Venezuela, Cuba, and Ecuador. This paradox likely reflects structural limitations within regional health systems, including underdiagnosis, restricted diagnostic capacity, and significant surveillance gaps, particularly in contexts where mild febrile syndromes may be misclassified as dengue, Zika, or Chikungunya. The regional risk of emergence is further amplified by climatic variability, ecological change, and intensifying human–wildlife interactions. Experiences from Europe highlight the importance of early detection, transfusion safety, and integrated surveillance within a One Health framework. Strengthening preparedness in Latin America will require investments in diagnostic infrastructure, implementation of standardized seroepidemiological surveys, development of predictive models tailored to local ecological contexts, and robust intersectoral collaboration. Full article

Accurate indoor localization in 5G remains challenging due to multipath propagation, signal blockage, and limited bandwidth in frequency range 1 (FR1). This study evaluates attention-based recurrent neural networks for two-dimensional user equipment (UE) localization using only positioning reference signal (PRS) magnitude data. We compare five models on the xG-Loc dataset (InF-DH scenario at 3.5 GHz, 5 MHz bandwidth): a simple GRU (M1), a deeper GRU with dropout (M2), a GRU optimized via Optuna (M3), a stacked GRU with multi-head attention (M4), and a bidirectional GRU with attention (M5). Model performance is quantified using the area above the cumulative distribution function (CDF) curve (AAC) metric, where lower values indicate better localization accuracy. Attention-based models significantly outperform baselines, and M4 achieves the lowest AAC of 6.71 (17% reduction versus M1’s 8.09), while M5 attains an AAC of 6.90. Statistical analysis confirms that M4 and M5 significantly outperform M3 (ANOVA, p < 0.000001). Optimal performance emerges with moderate numbers of time steps (TS ≈ 500 to 2500), with performance plateauing and degrading at higher values. These findings demonstrate that attention mechanisms substantially enhance 5G indoor localization accuracy using only PRS magnitudes, and that automated hyperparameter optimization improves model robustness. Full article

This study presents a comprehensive evaluation and environmental risk assessment (ERA) of pharmaceutical residues in the Cerrón Grande Reservoir, one of the most important surface water bodies in El Salvador. Sampling campaigns were conducted over a one-year period, covering both the dry (January 2024) and rainy (July 2024) seasons. A total of 76 pharmaceutical compounds were analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS), of which only five were not detected. During the dry season, the highest environmental concentrations were observed for mecamylamine (1710–6913 µg L⁻¹), 1,7-dimethylxanthine (379–2829 µg L⁻¹), chloroquine (2.29–362.7 µg L⁻¹), and hydroxychloroquine (5.02–315.4 µg L⁻¹). Concentrations generally decreased in the rainy season, with mecamylamine (1526–2198 µg L⁻¹), 1,7-dimethylxanthine (0.018–0.55 µg L⁻¹), and caffeine (0.2–0.474 µg L⁻¹) remaining the most prevalent. Compounds exceeding 1 µg L⁻¹ were assessed using predicted no-effect concentrations (PNEC) to calculate risk quotients (RQ). Chloroquine (RQ = 3346.3), mecamylamine (RQ = 1437.8), hydroxychloroquine (RQ = 1027.2), and manidipine (RQ = 271.0) posed the highest risks during the dry season, while only mecamylamine (RQ = 502.0) exceeded this threshold in the rainy season. To our knowledge, this represents the first in-depth study of pharmaceutical residues in Salvadoran surface waters, providing a foundational reference for future research and environmental policy in the region. Full article

In a context marked by polarization and diminished trust in nonviolent solutions, this article examines whether Christian political discernment can offer a viable response to the apparent inevitability of war. In light of Pope Francis’s critique of the applicability of just war reasoning amid today’s global arm’s race and advanced technology, this study investigates how Ignacio Ellacuría confronted the question of violence in El Salvador and reflects on its transnational relevance for Christian ethics in the face of contemporary conflicts. Through a close reading of Ellacuría’s philosophical and theological writings, informed by Xavier Zubiri’s philosophy, this article reconstructs the ambiguities and multiple meanings of violence that arise in situations of structural injustice and limit situations. Ellacuría’s commitment to the historical reality reveals his critique of the deficiencies of abstract or universal theories, including the appeal to legitimate defense, in favor of a praxis of discernment grounded in the lived experience of the poor. This study finds that Ellacuría locates the epistemic center of political judgment in the suffering of victims. This article concludes that Ellacuría’s provides an important contribution for renewing Christian political ethics in the 21st century by prioritizing the voices of those who suffer as the fundamental criterion for responding ethically to democratic crises and structural oppression. Full article