Universidade Federal Rural do Rio de Janeiro

The Weak Visible n → π* Transition of CF3NO: Vertical Accuracy versus Spectral Agreement

Abstract Trifluoronitrosomethane (CF3NO), one of the few relatively stable blue gases, owes its color to a weak, structured n → π* absorption near 690 nm. Its small size suggests a straightforward benchmark, yet vertical excited-state methods place this transition very differentl...

Land use impairs soil quality in a Histosol: a comparative study between conventional cultivation and secondary forest

Histosols provide key ecosystem services, including carbon storage, hydrological regulation, and biodiversity support; however, the effects of conventional agriculture on their quality in tropical regions remain poorly understood. In this study, we evaluated the effects of differ...

Soil-plant-animal properties and microbial reassembly distinguish cattle oral disease prevalence across converted Amazon pasture systems

Forest-to-pasture conversion can alter soil properties, forage composition, and microbial communities, but whether these changes are associated with bovine periodontitis remains unclear. We compared eight pasture systems in the Western Brazilian Amazon classified by high or low h...

Influence of Residual Lignin on Mechanical Fibrillation and Colloidal Stability of Cellulose Nanofibrils from Eucalyptus Kraft Pulp

Eucalyptus kraft pulping represents an important source for the production of lignin-containing cellulose nanofibrils (LCNF); however, the influence of controlled residual lignin levels on fibrillation energy demand and suspension stability remains poorly understood. This study e...

Molecular and Histopathological Findings of Giardia duodenalis in Rodents and Bats from the Atlantic Forest and Cerrado of Southeastern Brazil

Giardia duodenalis is a globally distributed intestinal protozoan infecting humans and animals. This study investigated its occurrence, genetic diversity, and histopathological findings in rodents and bats from the Atlantic Forest and Cerrado of southeastern Brazil. A total of 51...

Changing the world from Latin America: Milton Santos between transnational networking and multilingual worldings

On the occasion of the centenary of the birth of Brazilian radical geographer Milton Santos (1926–2001), we publish here for the first time the text of a guest lecture that he gave at the Fourth Meeting of Latin American Geographers (EGAL) in Mérida, Venezuela, in 1993. Unusually...

Synthesis and Biological Evaluation of Prazosin-Derived Antitrypanosomal Agents Putatively Targeting FAZ1

Abstract Current therapeutic interventions for Human African Trypanosomiasis (HAT) are severely limited by emerging drug resistance and profound systemic toxicity, necessitating the urgent development of novel chemotypes. Building upon our previous identification of the alpha-adr...

Discovery of First Quinoline–Acylguanidine Hybrids as Selective Butyrylcholinesterase Inhibitors: Design, Synthesis, and Molecular Basis

Alzheimer’s disease (DA) remains a major therapeutic challenge, and selective butyrylcholinesterase (BChE) inhibition has emerged as a promising strategy for symptomatic treatment, particularly in advanced stages. Herein, a series of novel quinoline–acylguanidine hybrids was desi...

Bisexual population of the parthenogenetic tick Amblyomma rotundatum: bioecological data from the field and laboratory

The tick Amblyomma rotundatum parasitizes primarily cold-blooded animals and is widely distributed in the Neotropics. This tick is considered parthenogenetic, with rare reports of males in nature. In the present study, we identified for the first time a bisexual population of A....

Large magnetocaloric effect in the EuSe1− x S x magnetic semiconductors with coexistence of the magnetic phases

We present the experimental results of the magnetic and calorimetric properties as well as the magnetocaloric effect of the EuSe1−xSx compounds with x = 0, 0.10, 0.16, 0.18, and 1. Magnetic and calorimetric results reveal complex low-temperature magnetic behavior arising from com...

Macrophyte litter diversity affects microbial respiration but not litter mass loss

Abstract Litter mixing effects (LME) may alter microbial-mediated decomposition in aquatic ecosystems, but it remains unclear whether these effects are related to the chemical diversity of litter and leachates or whether they change over time. Furthermore, most aquatic studies of...

(TD)DFT investigation of donor influence on the electronic and photovoltaic properties of D-π-A-π-A quinoxaline dyes

Abstract Context The design of efficient metal-free organic dyes is crucial for improving the performance of dye-sensitized solar cells (DSSCs). In this work, we investigated the influence of different donor groups on the electronic, photophysical, and photovoltaic properties of...

Bioactive Constituents of Melipona quadrifasciata anthidioides Geopropolis with Antifungal Activity against Sporothrix brasiliensis

Abstract Sporotrichosis caused by Sporothrix brasiliensis represents an emerging public health challenge in Brazil, with increasing therapeutic limitations and antifungal resistance. This study investigated Brazilian geopropolis produced by Melipona quadrifasciataanthidioides as...

A new perspective on centroid algorithms for unsupervised discrete clustering in Riemannian manifolds: an approach via optimization

Abstract Clustering is an unsupervised learning technique used to discover hidden structures in data. By identifying patterns and similarities among objects, this methodology enables the organization of datasets into homogeneous groups. This work presents a new perspective on a s...

O-Glycosylated Oncofetal Fibronectin Expression in Lesions of Human Cutaneous Leishmaniasis: A Novel Finding in Infectious Diseases

Cutaneous leishmaniasis (CL) is a chronic infectious disease characterized by extensive tissue destruction and profound extracellular matrix (ECM) remodeling. This study provides the first evidence of O-glycosylated oncofetal fibronectin (onf-FN) expression in human CL lesions. I...

Egg quality and performance responses to dietary calcium and phosphorus concentrations in laying hens of different ages

Context The balance of dietary calcium (Ca) and phosphorus (P) plays a crucial role in laying hen performance and egg quality, yet optimal concentrations for these minerals are not well-defined, particularly across different ages. Aims This study aimed to evaluate the effects of...

Kinetic and Oxidative Stability of Oil-in-Water Pickering Emulsions Stabilized by Lysozyme-Ferulic Acid Conjugates

The demand for ingredients with natural appeal has driven the development of multifunctional natural emulsifiers. This study aimed to synthesize covalent conjugates of lysozyme (LYS) and ferulic acid (FA) via a free radical reaction and investigate their application in stabilizin...

Shift vector sign reversal in the Alcubierre warp drive spacetime geometry and nonlinear Burgers-type dynamics

Abstract This work investigates a sign reversal of the shift vector in the Alcubierre warp drive geometry and its effect on the nonlinear reduced structure of the Einstein equations. Previous analyses showed that Burgers-type equations can arise in warp drive spacetimes, leading...

Silent spreaders: multidrug-resistant and hypermucoviscous Klebsiella from animals threaten one health

This study investigated the identification, antimicrobial resistance patterns, and phenotypic and genotypic traits of 30 Klebsiella isolates recovered from diverse animal species and infection sites. MALDI-TOF MS demonstrated higher accuracy in species-level identification than c...

Hepatic encephalopathy associated with extensive hepatic diaphragmatic herniation in an adult horse

Abstract Background Diaphragmatic hernia in horses is a rare condition, most commonly presenting with signs of colic and, less frequently, respiratory compromise. Hepatic herniation through a diaphragmatic defect with secondary hepatic failure and encephalopathy has rarely been d...