Universidad Nacional de Colombia

Far-Field Tsunami Observations of the 29 July 2025 Mw 8.8 Kamchatka Earthquake and Comparison with other Far-Field Tsunamis on the Mexican Pacific Coast

The Mw8.8 Kamchatka earthquake occurred offshore southern Kamchatka on July 29, 2025, generating a tsunami that propagated across the Pacific Ocean and produced a measurable sea-level disturbance along the Mexican Pacific coast. In this study, we analyze tide-gauge records along...

Mid-Miocene palaeohydrology archived in palaeosols of La Tatacoa, Colombia

Abstract Mid-Miocene palaeosols of the Baraya Member (Villavieja Formation, La Tatacoa, Colombia) record contrasting pedogenic pathways developed within fine-grained floodbasin environments under subhumid tropical conditions. The Ferruginous Red Bed (FRB) and La Venta Red Bed (LV...

Mitigation of Acrylamide in Panela: Evaluating Storage and Additive-Based Strategies on Physicochemical Properties and Sensory Quality

Abstract Panela, a traditional non-centrifugal cane sugar sweetener, undergoes intensive thermal evaporation promoting acrylamide (AA) formation through Maillard reactions. This study characterized AA formation throughout traditional panela production in Útica, Colombia, and qua...

Optimization of an in vitro drug screening assay for anti- Trypanosoma cruzi activity using epimastigotes

Abstract Chagas disease, caused by Trypanosoma cruzi, poses a significant global health burden. Current treatment relies solely on benznidazole and nifurtimox, both with limited efficacy and significant adverse effects. In vitro phenotype-based screening enables identification of...

Amazon Forgotten Fishes. How the remarkable diversity of freshwater fishes is critical to people, rivers and forest

Across the vast sweep of the Amazon Basin, thousands of rivers, streams and floodplain lakes flow in an immense, interconnected waterscape— home to an unparalleled diversity of freshwater fishes. More than 2,700 species have so far been recorded, with dozens more added each year...

Carotenoid-enriched endolithic phototrophic communities in Colombian gypsums

Gypsum has been shown to serve both as a protective shield against intense solar irradiation and as a microhabitat for microbial life, particularly under extreme environmental conditions. This study presents the first report of endolithic photosynthetic microbial communities and...

Nilpotent graphs over skew PBW extensions

We study the diameter and girth of nilpotent graphs associated with skew PBW extensions over $2$-primal rings, generalizing similar results on skew polynomial rings. Under certain compatibility conditions, we establish bounds for the diameter of the nilpotent graph and prove inva...

Transethmoidal encephalocele associated with granulomatosis with polyangiitis: A case report

Encephaloceles are uncommon lesions, most of which are congenital, and may be overlooked in routine radiologic practice. Failure to identify a skull base defect and characterize the herniated contents may delay recognition of associated abnormalities and clinically important comp...

Quantum states of three 3He atoms confined in a C60 fullerene

We employ a Non-Coulombic Non-Orthogonal Configuration Interaction (NC-NOCI) approach to study the confinement of three fermionic helium atoms, 3He, inside a C60 fullerene, with the aim of elucidating how encapsulation affects their spatial distribution and energy-level structure...

Muscle architecture and functional anatomy of the extrinsic thoracic limb muscles in a semiarboreal xenarthran (Tamandua mexicana)

Abstract Tamandua mexicana is a mammal belonging to Xenarthrans, with high interest in medicine, conservation, and evolutionary studies. It has semiarboreal locomotion with specific adaptations to allow its movement on different substrates. To carry out this type of locomotion, t...

Development of SpriteOptics: A Python-Based Framework for Synthetic Optical Emission Modeling of Sprite Streamers

Transient Luminous Events (TLEs), particularly sprites, are short-lived electrical discharges occurring in the upper atmosphere and producing characteristic optical emissions. Numerical streamer simulations provide valuable information on their dynamics and electrodynamic propert...

Development of SpriteOptics: A Python-Based Framework for Synthetic Optical Emission Modeling of Sprite Streamers

Transient Luminous Events (TLEs), particularly sprites, are short-lived electrical discharges occurring in the upper atmosphere and producing characteristic optical emissions. Numerical streamer simulations provide valuable information on their dynamics and electrodynamic propert...

TSH-induced post thyroidectomy spontaneous ovarian hyperstimulation syndrome: a rare case report of molecular mimicry

Abstract Background: Spontaneous ovarian hyperstimulation syndrome (sOHSS) is an exceptionally rare condition, particularly when associated with profound primary hypothyroidism (Type III sOHSS). Unlike the common iatrogenic form, it occurs without exogenous ovulation induction. C...

A sustainability index for strategic mine planning: integrating closure and environmental costs into phase prioritization

Abstract This paper proposes a phase-based evaluation workflow for strategic mine planning in which environmental and closure costs associated with each project phase are quantified after a base-case block sequencing and then compared with the economic performance of the resultin...

Climatic factors as drivers of elevational shifts in the montane forests-paramo boundary over the last 15,000 years in the northwest Andes

In this study, conducted in the Belmira paramo in the northwestern Andes of Colombia, we used pollen records to track vegetation changes over the past 15 calibrated thousand years before AD 1950 (cal kyr BP). Employing ordination (NMDS), species indicator, and wavelet analysis, w...

Regional Hydroclimatic Sensitivity of Monthly Precipitation Anomalies to ENSO in the Colombian Andes and Orinoquia

El Niño–Southern Oscillation (ENSO) modulates tropical South American rainfall, but its Colombian expression is filtered by terrain, rainfall regime, moisture pathways, and atmospheric state. We quantify ENSO-related sensitivity of standardized precipitation anomalies in the Colo...

History of divergence and gene flow shaping geographic variation in Andean warblers (Myioborus).

Studying how genetic variation is structured across space, and how it relates to divergence in phenotypic traits relevant to reproductive isolation, is important for our understanding of the speciation process. We used ddRAD-seq data to examine genetic variation across the distri...

On Pell, Narayana and Padovan Languages and Their Generalizations

In this article, we study several languages associated with classical integer sequences such as the Pell, Narayana, and Padovan sequences, as well as various generalizations. Some of these languages arise naturally in the context of graph theory. We show that a subset of these la...

Anchors for Homology-Based Scaffolding

Homology-based scaffolding orders contigs based on conserved collinearity of homologous sequences across related species. Existing methods often rely on costly whole-genome alignments or show limited robustness when integrating multiple references. Here, we introduce an anchor-ba...

Skew-symmetric augmented matrices and a characterization of virtual doodles

Abstract In this paper, we present a brief overview of the concept of doodles from the perspective of J. S. Carter’s work on classifying immersed curves and the work of J. Carter, S. Kamada, and M. Saito on stable equivalence of knots on surfaces and virtual knot cobordisms. We u...