Recent publications
Resumo Os índios, em especial aqueles provindos do que então era entendido como “mestiçagem” ou “miscigenação” com brancos e negros, tornaram-se um fator-chave no plano teórico do médico e antropólogo Raimundo Nina Rodrigues. Habitualmente, sua herança intelectual é vinculada à população “áfrico-bahiana”, posto seus estudos detalhados sobre etnologia urbana. Este artigo busca explorar, dentre suas propostas, o papel do “brasílio-guarany” e seu fator nocivo para o desenvolvimento do país, na ótica cientificista. Nina Rodrigues abriu diálogo com dois autores de destaque no século XIX sobre os ameríndios do Norte do país (em especial Pará e Amazonas), José Veríssimo e Couto de Magalhães. Sustentamos que o resultado deste confronto de ideias é um exemplo contundente de como o médico maranhense realizou certo deslocamento de sua posição em face do racismo científico, do qual ele se afasta (mas não abandona), incorporando elementos do evolucionismo-social e criando uma leitura única das relações sociais e biológicas entre as chamadas três raças formadoras da nação.
Eucalyptus (Eucalyptus spp., Mirtaceae) stands out for its remarkable regeneration capacity, making it a valuable tool for recovering degraded areas and for reforestation. Despite its Australian origins, eucalyptus has shown remarkable adaptation to the Brazilian tropical climate, contributing to the wood productivity of the country. However, the extensive monoculture of eucalyptus can increase pest incidence, thus being a significant challenge for the forestry sector, which suffers production losses of up to 30%. We analyzed the occurrence of 11 pest insect species in 450 eucalyptus stands over 9 years in the southeastern region of Brazil in our study. We related pest occurrences to specific year periods and climatic variations using circular uniformity analysis and zero-inflated models. We found that the species generally had isolated peaks of occurrence during the year and that the increase in the occurrence of at least five species was related to temperature or precipitation. The results highlight the sensitivity of pests to climatic conditions, showing the importance of management strategies to ensure the sustainability and productivity of eucalyptus plantations. We can develop more effective management strategies by understanding how these variables interact with insect populations, contributing to the sustainability and productivity of eucalyptus plantations with less aggressive environmental practices.
Objective To analyse vaccination coverage and factors associated with incomplete polio vaccination in a cohort of children born in 2017-2018, in state capitals and interior region municipalities of Northeast Brazil. Methods Household survey of children aged ≤24 months conducted between 2020 and 2022. Vaccination coverage and dropout rates were estimated, as well as factors associated with incomplete vaccination, analyzed by calculating odds ratios (OR) and 95% confidence intervals (95%CI). Results : Among 12,137 children, vaccination coverage (4 doses) was 80.9% (95%CI 78.4;83.1); 8.4% were not vaccinated. Not having a vaccination card (OR=18.06; 95%CI 10.01;32.61) and use of private services (OR=1.46; 95%CI 1.23;1.74) were associated with incomplete vaccination. Higher dropout rates were found for the booster dose, especially in the highest stratum. Conclusion Low vaccination coverage, poor dose follow-up and high dropout rates were found for polio vaccines in the areas studied.
Mosquitoes, particularly Aedes aegypti, pose significant public health risks by transmitting diseases like dengue, zika and chikungunya. Bacillus thuringiensis var. israelensis (BTI) is a crucial larvicide targeting mosquitoes while sparing other organisms and the environment. This study evaluated the effects of sublethal BTI doses on Ae. aegypti larvae regarding mortality, development, adult emergence and size, using a wide-area spray application in an urban neighbourhood. Laboratory experiments with four BTI concentrations (0, 0.008, 0.02 and 0.04 ppm) assessed compensatory and over compensatory responses. The spray achieved over 90% larval mortality within 48 h, but accumulating sublethal doses could trigger compensatory and over compensatory effects, enhancing the fitness of survivors. A dose–response relationship was evident, with higher BTI concentrations leading to increased mortality, reduced longevity and fewer pupae. BTI exposure also skewed the sex ratio towards males and altered adult sizes, potentially affecting population dynamics and vectorial capacity. These findings highlight the effectiveness of BTI in Ae. aegypti control and the importance of understanding compensation, overcompensation and density-dependent effects. While wide-area BTI applications can reach inaccessible breeding sites and offer potent mosquito control, careful consideration of ecological and evolutionary consequences is crucial.
Mangroves are essential tropical ecosystems nurturing a wide range of marine biodiversity and counteracting global warming by sequestering atmospheric carbon dioxide. Hence, the export mechanisms and fluxes of particulate and dissolved organic carbon and trace elements from mangroves directly influence coastal productivity, the global carbon cycle and thus global climate, which are, however, not well constrained. Here we find consistent radiogenic neodymium and hafnium isotopic compositions of porewater, sedimentary iron-manganese oxyhydroxides and coastal seawater, suggesting that the Amazonian mangrove belt supplies trace elements through porewater discharge, dissolution of iron-manganese oxyhydroxides and their interactions with seawater. Together, these processes supply 8.4 × 106 g yr⁻¹ dissolved neodymium, equivalent to 64% of the total sources of neodymium to the Amazonian coastal seawater. Globally, mangrove systems along the continental margins contribute 6–9% of the net neodymium input to the ocean, which is similar to the contributions from atmospheric deposition. A contribution of this magnitude is potentially also the case for other trace elements, given the strong correlations between neodymium and iron (Pearson r = 0.92), and manganese (r = 0.75) concentrations across the entire river-ocean section, emphasizing the crucial role of mangrove system inputs in micro-nutrient cycling.
Background
Considering the significant participation of the microenvironment in the local aggressiveness of odontogenic keratocysts, this study aims to evaluate the expression of ADAMTS-1 and its substrates, versican, aggrecan and brevican in this locally invasive odontogenic cyst.
Methods
Immunohistochemistry and polymerase chain reaction (PCR) were conducted on 30 cases of odontogenic keratocysts (OKCs) and 20 dental follicles (DFs).
Results
The immunohistochemical expression of these proteins was predominantly cytoplasmic and granular across all samples. In epithelial tissue, the immunoexpression of aggrecan and versican was higher in OKC (p < 0.05) compared to DF. Comparing the expression of proteins between the OKC epithelium and the cystic capsule, it was observed that all molecules were more expressed in the epithelium (p < 0.001). RT-PCR confirmed the expression of ADAMTS-1 and proteoglycans in all samples.
Conclusion
ADAMTS-1, aggrecan, brevican, and versican were expressed in all samples with a granular and cytoplasmic pattern. RT-PCR confirmed their presence in both OKC and DF, but only aggrecan and versican exhibited significantly higher levels in OKC (p < 0.05). Protein expression was notably greater in the epithelial component of OKC. These findings underscore the potential role of these proteins in the biological behavior of OKC.
In this article, we analyze a vibrating Timoshenko beam system with suspension in a one-dimensional bounded domain, under nonlinear localized internal damping mechanisms affecting all three wave equations. Specifically, we prove that damping applied to an arbitrarily small interval with positive measure, no matter how small, is effective. We also establish the existence and uniqueness of solutions using nonlinear semigroup theory and determine some rates of decay for these solutions without assuming any relationship between the coefficients. Additionally, we prove a result concerning internal observability for the conservative system to achieve the aforementioned asymptotic behavior.
Background
Tooth wear is an important mechanism for reducing dental dimensions and, consequently, dental crowding. The objective of this cohort study was to examine the relation of tooth wear, adjusted for covariates (age, tooth loss, arch perimeter and intercanine width), on tertiary crowding in Amazon Indigenous populations.
Methods
A sample of 40 Indigenous people in permanent dentition at T0 (baseline) and after 13 years (T1) were evaluated. The sample included 16 males and 24 females belonging to two villages, Arara ( n = 22, mean ages 16.6 and 29.9 years) and Assurini do Xingu ( n = 18, mean ages 16.0 and 29.6 years). Clinical, intraoral photograph and dental cast evaluations were performed at both times. The anterior crowding was measured using Little’s Irregularity Index (LI) and modeled through a multilevel linear regression with the predictor variables: village, tooth wear (T1-T0), age (T0), tooth loss (T1-T0), changes in intercanine width (T1-T0) and changes in arch perimeter (T1-T0).
Results
A slight increase was observed (< 1 mm) in anterior dental crowding and a decrease in arch perimeter < 1.5 mm, while tooth wear increased between 0.65 and 0.99 units. The contextual variable (village) had no significant association with LI. In the upper arch, tooth loss was the only variable that showed an inverse association with LI (β=-0.41, p < 0.05). In the lower arch, the increase in dental crowding was inversely associated with tooth wear (β=-1.30, p < 0.05) and changes in arch perimeter (β=-0.31, p < 0.05). The other variables did not show significant associations.
Conclusion
After 13 years, dental crowding and tooth wear increased, while the arch dimensions tended to decrease. The changes in long-term dental crowding seem to have distinct etiological components for each dental arch. In the mandible, the changes in incisor alignment were associated with increased tooth wear and decreased dental arch dimensions. Whereas in the maxilla, only tooth loss caused alterations in tooth alignment. It is suggested that the effect of increased tooth wear on the etiology of tertiary crowding is of small magnitude and restricted to the lower dental arch.
The study of emerging contaminants (ECs) in water resources has garnered significant attention due to their potential risks to human health and the environment. This review examines the contribution from computational approaches, focusing on the application of machine learning (ML) and molecular dynamics (MD) simulations to understand and optimize experimental applications of ECs adsorption on carbon-based nanomaterials. Condensed matter physics plays a crucial role in this research by investigating the fundamental properties of materials at the atomic and molecular levels, enabling the design and engineering of materials optimized for contaminant removal. We provide a comprehensive discussion of various force fields (FFs) such as AMBER, CHARMM, OPLS, GROMOS, and COMPASS, highlighting their unique features, advantages, and specific applications in modeling molecular interactions. The review also delves into the development and application of reactive potentials like ReaxFF, which facilitate large-scale atomistic simulations of chemical reactions. Additionally, we explore how ML models, including sGDML and SchNet, significantly enhance the potential and refinement of classical models by providing high-level quantum descriptions at reduced computational costs. The integration of ML with MD simulations allows for the accurate parameterization of FFs, offering detailed insights into adsorption mechanisms. Through a qualitative analysis of various ML models applied to the study of ECs on carbon materials, we identify key physical and chemical descriptors influencing adsorption capacities. Despite these advancements, challenges such as the limited diversity of ECs studied and the need for extensive experimental validation persist. This review underscores the importance of interdisciplinary collaboration, particularly the contributions of condensed matter physics, in developing innovative materials and strategies to address the environmental challenges posed by emerging contaminants.
Objective
The expansion of human activities in northern Colombia has increased human-snake encounters, particularly with venomous Porthidium lansbergii lansbergii. Given the limited knowledge of systemic envenomation effects and previous studies focusing only on early murine symptoms, this investigation aimed to describe the time-course physiopathology of P. lansbergii lansbergii envenomation following intramuscular injection in vivo.
Methods
Venom was inoculated in the gastrocnemius muscles of Swiss Webster mice, and blood, urine, and tissue samples were taken at different times to evaluate lethality and biochemical markers of renal function and oxidative stress.
Results
This study reports the first intramuscular LD50 for P. lansbergii lansbergii venom at 24.83 mg/Kg. Administering 80% of this LD50 induced early signs of renal injury, evidenced by urinary biomarkers over 24 h. The antioxidant activity was found at low levels in kidney tissue throughout the evaluated time post-envenomation. Malondialdehyde activity increased at the earliest point, while proinflammatory activity increased later. Urine metabolomics revealed elevated taurine and allantoin in the envenomed groups.
Discussion
Compensatory mechanisms in response to oxidative stress and tissue damage induced by the venom were evident in the envenomed mice over the evaluated time. However, histological analysis revealed evidence of pro-inflammatory processes occurring only at early times. Metabolomic analyses of urine samples identified taurine as a potential early biomarker of elevated oxidative stress and protein and creatinine levels.
Conclusions
P. lansbergii lansbergii venom induces alterations in murine renal tissue, affecting urinary biomarkers of kidney function within hours post-envenomation. Delayed proinflammatory effects may suggest an antioxidant imbalance in the envenomed mice, with unknown long-term effects. Further research on the role of oxidative stress and inflammation in renal structure and function following envenomation is necessary, emphasizing the need for prompt clinical management.
We investigate the dynamics of two-dimensional assemblies of rod-shaped magnetic colloids under the influence of an external rotating magnetic field. Using molecular dynamics, we simulate the formation of patterns that emerge based on the synchronization degree between the magnetic rods and the rotating field. We then explore the structural and dynamic characteristics of the resulting steady states, examining their evolution as a function of changes in the rods' aspect ratio, the strength of the external magnetic field, and its rotation frequency. Three distinct synchronization regimes of the rods with the magnetic field are clearly observed. A detailed set of phase diagrams illustrates the complex relationship between the magnitude of the external magnetic field and its rotation frequency and how these parameters govern the formation of unique self-organized structures.
Stress occurs as a reaction to mental and emotional pressure, anxiety, or scarring. Chronic stress is defined as constant submission to these moments. It can affect several body systems, increase blood pressure, and weaken immunity, thereby interfering with physiological health processes. Thus, this study aims to evaluate the effects of chronic stress on the redox status and histomorphological parameters of salivary glands. Thirty-two albino Wistar male rats were randomly divided into two groups: chronic stress and control. Chronically stressed animals were subjected to a restraint protocol by introducing them into a polyvinyl tube for 4 hours daily for 28 days, allowing immobilization of their movements. Subsequently, the animals were euthanized for further collection of the parotid and submandibular salivary glands. The redox state of the glands was evaluated using the antioxidant capacity against peroxyl radicals (ACAP) and thiobarbituric acid reactive substances (TBARS) assays. Histological analysis was performed through morphometry of the tissues stained with hematoxylin and eosin and histochemical through picrosirius red staining. Both the parotid and submandibular glands of stressed rats exhibited oxidative stress due to a decrease in ACAP and an increase in TBARS levels. However, the parotid glands are more susceptible to harmful changes in the tissue, such as an increase in the stromal area and in the collagen area fraction, decrease in the acinar area, and smaller size of the acinus and ducts. Our results suggest that chronic stress may cause harmful modulation of the redox state of the salivary glands, with different histological repercussions.
This study provides a comprehensive analysis of Ground Penetrating Radar (GPR) data processing techniques for detecting water leakage in urban pavements. By examining GPR images characterized by continuous and discontinuous high-amplitude reflections, the research identifies clear indicators of water saturation caused by leaking underground pipes. Computer modeling of GPR profiles enables effective comparisons with real data and helps in calibrating key GPR attributes such as energy, amplitude variance, and RMS amplitude. These attributes allow for the precise delineation of leakage zones in both synthetic and real GPR datasets collected in the Amazon region of Brazil. The Reflector Tilt Method (RTM) significantly enhances GPR data analysis, especially for detecting subsurface water leaks. RTM utilizes changes in the relative dielectric constant and electromagnetic wave velocity induced by water saturation in unconsolidated, horizontally stratified sand layers. By analyzing the tilt of reflections in GPR profiles, RTM differentiates between dry and saturated zones, providing insights into the geometry and extent of water infiltration. Notably, this study demonstrates how increased subsurface water saturation causes underlying reflectors to tilt. Using the tilt angle, we propose a novel technique to quantify the increase in the dielectric constant due to water saturation. This technique could also be adapted to detect leaks involving other fluids, as long as there is a strong contrast between the dielectric constant and the background. The integration of RTM improves the creation of accurate three-dimensional models of affected areas, enhancing leak detection and aiding in understanding water movement dynamics within the subsurface. The study underscores the importance of combining GPR attributes with RTM to generate detailed 3D models of leakage zones, which are essential for estimating the volume of infiltrated areas. Observations indicate significant water saturation near leaking pipes at shallow depths, with saturation levels decreasing rapidly as depth increases. By identifying 2D geophysical signatures of water leaks in public distribution networks, the research highlights the effectiveness of non-invasive GPR methods in mitigating risks such as soil erosion and surface collapse. This approach demonstrates the utility of GPR attributes and RTM as essential tools for assessing urban pavement integrity, enabling early João Andrade dos Reis Júnior et al. 2 detection of leaks and precise mapping of affected zones. The findings contribute significantly to the efficient and sustainable management of urban infrastructure, enhancing maintenance strategies and reducing potential hazards associated with undetected fluid leaks.
A dynamical model is used as a simple GCM to perform historical forecasts for rainfall in northeastern Brazil for the years 1982–2020. The model is forced by empirically derived source terms and includes basic parameterisations to simulate vertical diffusion, convection and condensation. Ensemble forecasts with 38 members are initiated on 1st January using persisted tropical sea surface temperature anomalies (SSTAs). Rainfall forecast performance is evaluated for the February–April (FMA) rainy season. The model reproduces the climatological precipitation in the specified Nordeste region with a mainly dry bias as the model rainfall maximum is displaced in the the northwest. Hindcasts for interannual rainfall anomalies correlate with observed values (r = 0.46) and model variance is weaker than observed. A further set of forecast experiments with SSTAs restricted to the three major ocean basins reveals that most of the forecast skill can be attributed to the Pacific, despite the model's greater sensitivity to Atlantic SSTAs. The sum of results from the three ocean basins is close to the full hindcast result. Finally, a set of 128 forecast runs with idealised SSTAs placed regularly within the tropics is carried out to calibrate the response of modelled rainfall to remote influences. An influence function is diagnosed in the form of a tropical distribution of northeastern Brazil rainfall in mm/day per unit SSTA. It is strongly concentrated in the tropical Atlantic, with dry/wet conditions resulting from positive SSTAs in the northern/southern tropical Atlantic, in keeping with the observed covariance. The influence function is the used to construct a linear approximation to the forecast performance of the simple GCM. It has similar skill but stronger variance, and the skill is partitioned differently between Atlantic and Pacific influences.
This study explores carbon sequestration in South Korea’s riverine wetlands, focusing on the four major rivers: Han, Yeongsan, Geum, and Nakdong. Field data from the Yeongsan River wetland, including 3D topography surveys, grainsize analyses, and loss-on-ignition measurements, were used to assess carbon stocks and their environmental drivers. The Yeongsan River was selected as a representative site due to its geomorphological, hydrological, and climatic similarities with the other three major rivers, which influence sediment transport and carbon dynamics. Carbon stocks of 3.31 megagrams (Mg) per hectare, observed in the Dam-Yang Stream Wetland, suggest that the four major rivers collectively have the potential to store approximately 23.42 million metric tons of carbon annually, accounting for 3.9% of South Korea’s carbon budget. Geomorphological features at different elevations significantly influence soil carbon storage, with finer sediments contributing to higher carbon retention in low-energy environments. Seasonal variations in stream geomorphology, driven by floods and tropical cyclones, are dominant factors regulating sediment transport and organic matter deposition. Our findings suggest that controlled discharge events could enhance sediment and organic material retention, boosting carbon sequestration across riverine wetlands. This study highlights the critical role of geomorphological and hydrological processes in enhancing wetland carbon storage and mitigating carbon emissions.
The study was conducted on a 3-year-old female Santa Inês sheep from a property located in the municipality of Santo Antônio de Tauá, west of Pará. The affected animal had a history of exophthalmos in the left eye, nasal discharge, and breathing difficulty for more than three months. On physical examination, the animal had a low body score, apathy, unilateral facial asymmetry, moderate unilateral left exophthalmos, mixed dyspnea and unilateral profuse serosanguinous nasal discharge. At necropsy, a large nasal mass was observed, predominantly yellowish-white with blackish-red areas, with an irregular, finely granular, moist, and friable surface. The mass invaded from the mucocutaneous junction of the left nostril to the choanae, infiltrated the frontal sinuses, the cribiform plate, and reached the meninges and the frontal portion of the brain. Microscopy of the surface of the nasal epithelium showed severe destruction of the turbinates and epithelia, evidenced by extensive areas of necrosis with a large amount of cellular debris, ulceration, and secondary bacterial infection. In the central nervous system there was pyogranulomatous meningitis with marked vessel congestion, as well as foci of necrosis and granulomatous inflammation. Immunohistochemistry showed intense staining of numerous intralesional hyphae for antibodies against Conidiobolus lamprauges. The diagnosis of granulomatous rhinitis of mycotic origin associated with the Conidiobolus lamprauges was based on epidemiological, clinical-pathological, and immunohistochemical data.
To improve the nutritional and functional quality of agro-industrial waste, his study established a ternary mixture of flours made from pineapple, acerola, and passion fruit waste using the simplex-centroid design, as well as to evaluate their effects on the physicochemical and sensory characteristics of edible ice cream. Using mixture planning, nine ternary flour components were applied to edible ice cream formulations to evaluate acceptance scores for taste, texture, and overall impression attributes, as well as physicochemical parameters (pH, acidity, soluble solids, and color parameters) and microbiological parameters (thermotolerant coliforms at 45 ºC, Enterobacteriaceae and Salmonella). The simplex-centroid design demonstrated that the cubic model best predicts the results for the analyzed sensory attributes. The response surface graphs indicated the area of greatest acceptance in the formulations with the maximum percentage established for the flour with acerola waste. The highest level of acceptability was given to the ternary mixture of 60%, 30%, and 10% pineapple, passion fruit, and acerola flours, respectively. The results indicated that sorbet enriched with flour composed of the ternary mixture is a product with the potential for exploitation, as well as contributing to the reduction of environmental impacts generated by the large and improper disposal of agro-industrial fruit processing residues in the ecosystem.
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