Universidad de Medellín

The seismic performance of residential buildings is a pressing concern in high‐seismicity regions. In Colombia, Thin Lightly Reinforced Concrete Wall (TLRCW) buildings have become a common solution to address the housing deficits. This study evaluates the impact of structural configuration on the seismic performance of 52 low‐ and mid‐rise constructed TLRCW buildings, examining key parameters such as stiffness index, wall index, aspect ratio, longitudinal reinforcement ratios distributed in the wall web and concentrated at the wall edge, wall thickness, and confinement. Numerical simulations in OpenSeesPy were used to assess the performance of archetypes under a set of hazard‐consistent ground motion records, generating fragility curves for each archetype. For each archetype, the seismic performance is evaluated in terms of the probability of collapse for the maximum considered earthquake (MCE). The results show that certain structural configurations can increase the probability of collapse for low‐rise and mid‐rise buildings. Specifically, very thin walls (80–100 mm) with aspect ratios greater than 6, light longitudinal reinforcement ratio distributed in the wall web using a single layer of welded wire mesh (less than 0.20%), and light vertical reinforcement concentrated at the wall edge (less than 0.50%) increase the probability in low‐rise buildings. In contrast, high steel ratios of vertical reinforcement concentrated at the wall edges (more than 2%) combined with low web reinforcement (0.20% or less) are key attributes in mid‐rise buildings that lead to unacceptable seismic performance.

Penetrating traumatic brain injury (pTBI) is a severe subset of cranial trauma associated with high mortality and a substantial burden of intracranial infections. The pTBI infection rates have decreased from approximately 60% in the pre-war era to about 10% today, due to improvements in operative debridement, critical care, and widespread antibiotic availability; however, the independent effect of prophylactic antibiotics remains uncertain, and clinical practice is highly variable. This systematic review and meta-analysis aims to determine whether prophylactic antibiotics truly reduce intracranial infections in pTBI patients. A systematic review and meta-analysis were conducted following PRISMA guidelines. The PubMed, Scopus, and LILACS were rigorously searched. The primary effectiveness outcome analyzed was the risk of central nervous system infection. Secondary outcomes included antibiotic regimens and duration, mortality, and functional outcomes were assessed. Data were analyzed using a random-effects meta-analysis, and statistical heterogeneity was assessed. The study was registered with PROSPERO (CRD420251033854). Eight studies comprising 1372 patients (891 received antibiotic prophylaxis and 481 did not) were included. We found that the administration of prophylactic antibiotics did not significantly reduce the risk of suffering an intracranial infection OR 1.10 (95% CI 0.29-4.22 I2 = 48.8%). Furthermore, there was no statistically significant difference between monotherapy and multiple antibiotics, or shorter versus longer courses. Moreover, only one study employed a standardized antibiotic regimen. Prophylactic antibiotic administration in patients with penetrating traumatic brain injury was not associated with a statistically significant reduction in the risk of intracranial infections, as evidenced by substantial heterogeneity in the available literature. However, if prophylaxis is administered, it should be a short-course, monotherapy regimen. These findings highlight the urgent need for high-quality, standardized clinical trials to establish evidence-based guidelines for the use of prophylactic antibiotics in this high-risk population.

Alopoglossus grandisquamatus is a species only known from its male holotype, collected almost 40 years ago. We report the rediscovery of the Largescale Lizard A. grandisquamatus based on two female individuals from two new localities, extending its known distribution 19 km eastwards and 100 km southwards. Conservation status of Endangered is proposed for A. grandisquamatus. Novel morphological variation is described, including sexual dimorphism in femoral pores. Synonymy of A. grandisquamatus with Alopoglossus eurylepis is discussed, with the dismissal of non-useful diagnostic characters. New characters such as number of femoral pores in males, gular scales arrangement and the number of transversal rows of ventral scales are proposed to diagnose A. grandisquamatus from A. eurylepis. Other characters used by previous authors to differentiate both species are also validated.

Magnesium has significant potential for hydrogen storage in the solid state because its capacity is about 7.6 wt%. However, the high stability of magnesium hydride requires operating temperatures superior to 380 °C for hydrogen release. It is well known that Ni could catalyze the hydrogen absorption and desorption in magnesium. In this study, carbon-coated nickel nanoparticles were employed as catalysts to enhance the hydrogen absorption and desorption kinetics of pre-hydrogenated magnesium particles. The carbon-coated nickel nanoparticles were uniformly dispersed across the surface of the pre-hydrogenated magnesium particles. In dehydrogenation at 375 °C and 350 °C, the best sample desorbs 4.90 and 4.1 wt%, respectively, in 10 min. After 45 cycles at 375 °C, the hydrogen desorption capacity is 4.91 wt%, indicating a retention capacity of 100%. Our results demonstrate that carbon-coated nickel nanoparticles can be effectively incorporated into pre-hydrogenated magnesium without the need for ball milling, significantly enhancing hydrogen absorption and desorption performance.

<title>Abstract</title> Oxygen carriers (OCs) are essential materials in chemical looping technologies for low-carbon hydrogen production; however, the environmental implications of their synthesis remain insufficiently explored. This study presents a gate-to-gate life cycle assessment (LCA) of a chamotte–nickel OC produced via wet impregnation, following ISO 14040/44 guidelines. The functional unit was 1 kg of OC, requiring 0.8 kg of chamotte, 1.042 kg of nickel nitrate, and 0.66 kg of water. Environmental impacts were modeled using ReCiPe 2016 Midpoint (H). Transportation dominated 15 of the 18 impact categories, particularly toxicity and resource depletion, while wet impregnation contributed 38.9% to climate change and 55.6% to terrestrial acidification. Thermal treatments were major sources of N₂O and NOₓ, significantly affecting climate change and human toxicity. Hotspot analysis identified precursor selection, energy supply, and logistics as key drivers of environmental burdens. Mitigation strategies—including precursor substitution, renewable-energy integration, low-energy synthesis routes, emission abatement, and industrial symbiosis—could reduce CO₂-eq emissions by 30–50% and NOₓ by up to 90%. These results offer actionable guidance for sustainable OC design and highlight the importance of integrating LCA into early-stage materials engineering to support cleaner hydrogen production and circular resource flows.

Abstract Background Ulcerative colitis (UC) requires effective therapeutic strategies to induce and maintain remission. Upadacitinib, a selective JAK1 inhibitor, has shown strong efficacy in clinical trials; however, real-world evidence in Latin American populations remains scarce. The UPARECOL-UC study evaluated the effectiveness and safety of upadacitinib in Colombian patients with UC during induction (8–16 weeks) and maintenance (24 weeks) under routine clinical practice. Methods A prospective multicentre cohort study was conducted across Colombian reference centres including adults with confirmed UC (clinical, endoscopic, and histological criteria) who initiated upadacitinib between 2024 and 2025 for ≥8 weeks. Effectiveness outcomes included clinical response, clinical remission, and steroid-free remission. Objective biomarkers (C-reactive protein, faecal calprotectin, haemoglobin) were monitored at baseline and follow-up. Safety variables included adverse events (AEs), serious AEs, infections, and treatment discontinuation. Results A total of 47 patients were included in the induction analysis. After 8–16 weeks, clinical remission was achieved in 61.7% (29/47), with steroid-free remission in 71.4% of responders. At week 24, clinical remission increased to 90% (18/20), and steroid-free remission reached 88.2%. Endoscopic remission (Mayo 0–1) was 85% among patients reassessed endoscopically during maintenance. Significant reductions in inflammatory biomarkers were observed during follow-up, supporting clinical improvement. Colectomy occurred in 5.4% of patients during induction, with no colectomies during maintenance. Overall, 30.2% experienced any AE; acne was the most common (25.6%). Serious infections occurred in 4.7% . Treatment discontinuation due to AEs occurred in 9.3% of the cohort. No new safety signals were identified. Conclusion Upadacitinib demonstrated high real-world effectiveness for both induction and maintenance in this Colombian UC cohort, composed largely of patients with severe and treatment-refractory disease. Improvements in clinical outcomes were accompanied by significant reductions in inflammatory biomarkers. The safety profile was consistent with previous clinical and real-world data, supporting upadacitinib as an effective therapeutic option for UC in routine practice. Conflict of interest: Parra Izquierdo, Leidy Viviana: No conflict of interest Gil Parada, Fabio Leonel: No conflict of interest Juliao Baños, Fabián: No conflict of interest Puentes-Manosalva, Fabian Eduardo: No conflict of interest Cuervo-Pico, Pedro-Eduardo: No conflict of interest Galiano, Maria Teresa: No conflict of interest Riveros, Javier: No conflict of interest Gomez Venegas, Alvaro: No conflict of interest Medrano-Almanza, Carlos Andres: No conflict of interest Perea, Daniel: No conflict of interest Ballesteros, Manuel: No conflict of interest Barreto Perez, Jonathan: No conflict of interest Cuadros-Mendoza, Carlos Augusto: No conflict of interest Guzman, Gerardo: No conflict of interest Gutierrez Raba, Aura: No conflict of interest Soto Mora, Jahir: No conflict of interest Dr. Frías-Ordoñez, Juan: No conflict of interest

El artículo presenta un estudio de caso comparado para analizar la vulnerabilidad institucional y la resiliencia comunitaria en la gestión del riesgo de desastres, a partir de dos experiencias pre y post desastre en el departamento de Antioquia (Colombia): El asentamiento La Primavera -municipio de Barbosa- (ex-ante), y el municipio de Salgar (ex-post). La investigación es de carácter mixto, mediante el marco comprensivo de los sistemas socioecológicos. En esta se analizan los atributos mencionados que varían según los modos e intensidad de las relaciones entre comunidad, Estado y sector privado. Se concluye que contextos de cambio climático, con baja capacidad institucional, débil articulación entre actores y bajos niveles de confianza institucional, devienen en mayor vulnerabilidad y baja resiliencia comunitaria, todo lo cual está mediado por las políticas públicas, con repercusiones en la gobernanza.

Abstract Background Defaecatory urgency is a cardinal and distressing symptom in ulcerative colitis (UC), strongly associated with disease activity and reduced quality of life. Its resolution represents a key therapeutic goal, often paralleling mucosal healing and remission. Upadacitinib (UPA), a selective JAK1 inhibitor, has demonstrated robust efficacy for induction and maintenance of remission in UC; however, its specific impact on urgency in real-world Latin American settings remains poorly characterised. Methods We conducted a multicentre observational study including adults with moderate-to-severe UC treated with UPA 45 mg/day for induction and 30 mg/day for maintenance. Changes in defaecatory urgency (present/absent), clinical response (≥3-point decrease in Mayo score), and clinical remission (Mayo &amp;lt; 2) were evaluated at weeks 8–16 (induction) and 24 (maintenance). Biochemical remission was defined as faecal calprotectin &amp;lt; 150 µg/g and/or C-reactive protein &amp;lt; 5 mg/L. Absolute differences were calculated with 95 % confidence intervals (CI), and Fisher’s exact test was applied for categorical variables (p &amp;lt; 0.05). Results A total of 47 patients with UC were included; mean age 39.8 ± 14.6 years; 59.6 % female; 83 % previously exposed to at least one anti-TNF agent. At baseline, 66 % of patients reported defaecatory urgency, which decreased to 31.9 % after induction (Δ − 34.1 %; 95 % CI − 49.5 to − 18.7; p = 0.001) and 25.5 % at six months (p = 0.003). Clinical response was achieved in 81.2 % (95 % CI 66.1–91.4), and clinical remission in 61.7 % (95 % CI 46.4–75.1). Improvement in urgency strongly correlated with clinical remission (r = 0.72; p &amp;lt; 0.001). Biochemical remission (faecal calprotectin &amp;lt; 150 µg/g or CRP &amp;lt; 5 mg/L) occurred in 57.4 % of patients. No serious adverse events were observed; mild transaminase elevations occurred in 8.5 %. Conclusion Upadacitinib rapidly and sustainably reduced defaecatory urgency in Colombian patients with moderate-to-severe UC, with improvement in over two-thirds of cases and a strong association with clinical remission and biomarker normalisation. These findings provide the first real-world Latin American evidence highlighting upadacitinib’s impact on patient-centred symptomatic control in ulcerative colitis, supporting its role as an effective induction and maintenance therapy.