Universidade Federal do Pará

Measuring Backdoor Persistence in Post-trained Large Language Models: The Cyber Resilience Scaling Coefficient

Data-poisoning backdoors implanted during supervised fine-tuning of large language models persist through subsequent clean training, yet the field lacks a bounded, scale-normalized metric for quantifying and comparing this persistence across architectures and training regimes. We...

A systematic review and individual patient data meta-analysis to determine the effect of primaquine dose on efficacy, tolerability and safety in uncomplicated Plasmodium vivax malaria in Latin America

Background Primaquine is widely used to prevent relapses of Plasmodium vivax malaria, but the optimal dose in Latin America is unknown. We undertook a systematic review and individual patient data meta-analysis to investigate the efficacy, tolerability and safety of different pri...

Advances in artificial intelligence and geomatics technology for the transformation of global agri-food systems: A review

Abstract The world’s rapidly growing population is driving up food demand and placing significant pressure on natural resources, posing major challenges to agricultural sustainability. Ensuring food security requires integrating innovative technologies that enhance productivity w...

Phytochemistry, Chemotypic Diversity and Antimicrobial Potential of Essential Oils From Native Aromatic Plants of the Americas: A Systematic Review

ABSTRACT Essential oils (EOs) derived from native aromatic plants represent a critical frontier for sustainable development, biodiversity conservation and innovative pharmacological applications in the Americas. This review synthesizes current scientific knowledge on the chemical...

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...

Effects of 24-Epibrassinolide Application on the Development of Dipteryx odorata: Between Growth Stimulation and Inhibitory Effects

Abstract Dipteryx odorata , the Tonka Bean tree, is an Amazonian tree species of high ecological and economic importance, widely used in reforestation and restoration programs. This study evaluated the effects of exogenous application of 24-epibrassinolide (24-EBL) on the morphol...

Toxicological evidence that methylmercury exposure amplifies bone destruction and systemic impact associated with apical periodontitis in rats

Abstract This study investigated whether long-term methylmercury exposure aggravates apical periodontitis in Wistar rats. Thirty-two male rats (90 days old) were randomized into four groups (n = 8): control, methylmercury, apical periodontitis, and methylmercury + apical periodon...

Plant-derived immunomodulatory compounds in experimental leishmaniasis: a systematic review

Abstract Leishmaniasis is a neglected tropical disease that remains a major public health problem in many endemic regions. Current treatments are limited by toxicity, high cost, and emerging drug resistance. Plant-derived compounds have been investigated as potential therapeutic...

Hybrid Integral Transform Solution of a Nonlinear Core-Flooding Model with Capillary Pressure and End Effects

Abstract Oil-water displacement in coreflooding experiments is governed by a nonlinear convection-diffusion equation derived from the extended Buckley-Leverett formulation that accounts for capillary pressure effects. When realistic constitutive relations are combined with nonlin...

A Brief overview on the existence of solution to a class of quasilinear integro-differential equations

Abstract In this paper, we are concerned with a class of integro-differential equations whose prototype is given by $$\begin{aligned} \left\{ \begin{array}{lcl} -div(a(u)\nabla u)+\eta \psi (x)\int _{\Omega } \varphi u = f(x,u), \text { in } \Omega ,\\ u=0, \text { on } \partial...

Seven years of monitoring the demography and population density of jaguars (Panthera onca) in a human-modified landscape of eastern Amazonia

The primary impacts of mining on wildlife are habitat loss and fragmentation, which reduce the availability of essential resources and disrupt ecological processes necessary for species persistence. Despite the growing expansion of mining activities in tropical regions, their eff...

Bertholletia excelsa Shell–Based Wood–Plastic with Upcycled Polypropylene: An Amazonian Feedstock for Circular Bioeconomy Applications

Environmental accumulation issues arise from discarded waste, synthetic, and natural polymers in landfills, whose slow degradation exacerbates the problem. These materials can be upcycled as renewable feedstocks and properly reused. Therefore, this research examines the fabricati...

Factors associated with discordance between the patient-reported Rheumatoid Arthritis Disease Activity Index (RADAI) and the Simplified Disease Activity Index (SDAI) concerning the achievement of treat-to-target goals – data from the REAL study

Abstract Background Treat-to-target (T2T) strategies in rheumatoid arthritis (RA) rely on regular assessment of disease activity using validated composite indices, with remission or low disease activity as therapeutic goals. The Simplified Disease Activity Index (SDAI) is widely...

Exploring genetic variability in FOXE1 through in silico approaches: new insights on UTR variants

<title>Abstract</title> The <italic>FOXE1</italic> gene is a transcription factor critical for thyroid development and function, and has been associated with thyroid disorders and other phenotypic traits like cancer and orofacial clefts. This study explores the genetic variabilit...

Mapping the IntermolecularInteraction Landscape ina New Nicotinamide–Undecanoic Acid Cocrystal: SupramolecularStructure, Spectroscopic Analyses, and Computational Studies

Abstract A novel cocrystal composed of nicotinamide (NA) and undecanoic acid (UA) in a 1:1 stoichiometry has been successfully synthesized via slow evaporation and comprehensively characterized through a multidisciplinary approach combining experimental and computational methods....

Persistent Redox Imbalance in Post-COVID-19 Syndrome: Lipid Peroxidation, Antioxidant Enzyme Depletion, and Reduced Nitric Oxide Availability in an Amazonian Population

Post-COVID-19 syndrome (PCS) can persist even after mild acute illness, and oxidative stress has been proposed as a central mechanism for this persistence, although it remains poorly studied in the Amazon. This study characterized redox imbalance in patients with PCS through a co...

Platelets as regulators of cancer immunity: mechanisms and therapeutic perspectives

Abstract Platelets correspond to one of the most abundant components of the blood and shape the tumor microenvironment, modulate antitumor immune responses, and influence clinical outcomes in cancer patients. Recent studies have expanded our understanding of the mechanisms underl...

Cation-Disordered TbNdFeCoO6 Double Perovskite: Structural, Vibrational, Magnetic, and Electrocatalytic Insights for Efficient Hydrogen Evolution Reaction

Abstract Double perovskite oxides have emerged as promising multifunctional materials for sustainable energy applications due to their tunable structural, electronic, magnetic, and electrocatalytic properties. In this research study, the cation-disordered double perovskite TbNdFe...

Microplastic Occurrence in Foragers of Two Neotropical Bee Species (Apidae: Meliponini) from the Eastern Amazon

Abstract Microplastics (MPs) are ubiquitous anthropogenic pollutants that originate from diverse sources and pose a significant threat to both aquatic and terrestrial ecosystems. Bees are considered active bio-samplers of air quality due to the accumulation of MPs on their bodies...

Global trends in artificial intelligence applications in medical imaging and implications for clinical practice

This study aimed to analyze the evolution of scientific production on AI applied to medical imaging, focusing on temporal trends, the global distribution of research, and trends in clinical applications. A bibliometric study was conducted using the Scopus and Web of Science datab...