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Guglielmo, M.

Publications and source records attributed to Guglielmo, M..

3 recordsLinked to original sources

Data-Driven Discovery of Mechanistic Ecosystem Models with LLMs

Ecosystem models are essential for ecosystem management, but their development traditionally requires significant time and expertise, creating bottlenecks in addressing urgent environmental challenges. We present LEMMA (LLM Enabled Mechanistic Modelling for ecosystem Assessment), a framework that programmatically generates and iteratively refines mechanistic ecosystem models by combining large language models (LLMs) for equation synthesis and parameter search, evolutionary algorithms for structural optimization, and Template Model Builder (TMB) for efficient parameter estimation. We critically review LEMMAs ability to recover known ecological relationships through two complementary marine case studies: (1) a nutrient-phytoplankton-zooplankton model, and (2) a Crown-of-Thorns starfish (COTS) model. In the first case, our best models displayed almost perfect recovery of known ecological dynamics while maintaining strong predictive performance across multivariate time-series. In the second case, best LEMMA generated models approached human expert models in terms of their ability to successfully capture COTS outbreak dynamics and demonstrated strong out-of-sample predictive power. LEMMA produces interpretable models with meaningful parameters that capture real biological processes, facilitating scientific insight and potentially accelerating management applications. By dramatically accelerating model development while offering ecological interpretability, LEMMA offers a powerful new tool for addressing urgent ecological challenges in a changing world.

ecology↗

The influence of larval retention on coral recruitment

Marine broadcast spawners typically exhibit bipartite life-histories with distinct pelagic larvae and benthic phases. The transition between phases shapes benthic populations, but the rate of larval arrival to a reef is largely unknown due to challenges in accurately measuring supply. Once larvae arrive to a reef, reduced current flow and velocity, facilitate the transition from the water column to the benthos for inefficient swimming larvae. Yet, for coral reefs characterised by complex hydrodynamics and tides, slack current conditions typically last 1.5-3 hours and it remains unclear if such short retention periods drive significant recruitment. This study mechanistically examined the effects of water retention on the settlement of coral larvae from the water column to the benthos and subsequent longer-term recruitment over 15-months. Brief periods of slack currents (<3-hours) retained larvae in unconstrained larval supply treatments, resulting in settlement rates 40-times higher than natural, background rates. Constrained and longer retention of larvae under nets for 2.5- and 24-hours resulted in 4-7-times higher initial settlement than the unconstrained treatment and 305-times higher than background rates. However, after 15-months, similar numbers of surviving recruits were observed across all larval supply treatments, highlighting the effects of density-dependent population regulation. Observations from recruitment tiles show survival rates of coral recruits after 15-months were low (<0.25), even though gregarious settlement behaviour and settlement close to tile edges improved survival. In contrast, observations from the natural substrate show survival rates were 2.5-3.5-times higher than tiles after 15-months, indicating density-independent survival due to optimal niche space and less space limitation. Therefore, when larval supply is high and gregarious behaviour prominent, key vital rates including recruitment and mortality derived from settlement tiles are likely overestimated, as substrate and microhabitat properties between tiles and natural reef environment vary. Overall, our study highlights the prominent role of slack current conditions and local retention of larvae in facilitating the supply-to-settlement transition, and how this interacts with density-dependent processes post-settlement. Our findings underscore the need to investigate how the interaction strengths of pre-and post-settlement processes modulate early coral recovery to best model recovery trajectories for conservation and restoration prioritisation.

ecology↗

Modeling the effect of COVID-19 disease on the cardiac function: a computational study

BackgroundThe effect of COVID-19 on the cardiac function and on the vascular system increases the morbidity and mortality of infected subjects with cardiovascular diseases. ObjectivesTo provide preliminary results on cardiac global outcomes (such as cardiac output, ventricular pressures) obtained by means of computational models in plausible scenarios characterized by COVID-19. MethodsWe considered a lumped parameters computational model of the cardiovascular system, which models, from the mechanical point of view, the systemic and pulmonary circulations, the four cardiac valves and the four heart chambers, through mathematical equations of the underlying physical processes. To study the effect of COVID-19, we varied the heart rate, the contractility and the pulmonary resistances in suitable ranges. ResultsOur computations on individuals with both otherwise normal and impaired cardiac functions revealed that COVID-19 worsen cardiac function, as shown by a decrease of some cardiac biomarkers values such as cardiac output and ejection fraction. In the case of existing impaired cardiac function, the presence of COVID-19 lead to values outside the normal ranges. ConclusionsComputational models revealed to be an effective tool to study the effect of COVID-19 on the cardiovascular system. Such effect could be significant for patients with impaired cardiac function. This is especially useful to perform a sensitivity analysis of the hemodynamics for different conditions. CONDENSED ABSTRACTEmerging studies address how COVID-19 infection might impact the cardiovascular system. This relates particularly to the development of myocardial injury, acute coronary syndrome, myocarditis, arrhythmia, and heart failure. Prospective treatment approach is advised for these patients. By the assessment of conventional important biomarkers obtained with new sources as a 0-dimentional computational model, we propose a new study protocol as an effective method to evaluate short-term prognosis. The clinical protocol proposed will help to rapidly identify which patients require intensive monitoring, diagnostic strategy and most adequate therapy.

pathology↗