Southern Brazil Research Articles

New record of Cyanallagma demoiselle Denck, Ehlert & Pinto, 2023 (Odonata, Zygoptera, Coenagrionidae) in southern Brazil

During a field expedition in the municipality of Araquari, state of Santa Catarina, southern Brazil, adults of the damselfly Cyanallagma demoiselle Denck, Ehlert & Pinto 2023 (Odonata, Zygoptera, Coenagrionidae) were collected. This species was recently described and reported to date for the southeastern Atlantic Forest in Brazil. Here, we recorded this species as well as its respective genus for the first time for the state of Santa Catarina, increasing its distribution range of the species to southwards and raising the number of Odonata species recorded for this state to 151.

The Surprising Survival of Constitutionalism in the Caudillo Republic of Rio Grande do Sul, Brazil, 1836–1845

Abstract The caudillo strongman remains emblematic of Latin American authoritarianism, but scholarship has seldom reflected on the semantic shifts that this concept suffered over time and its implications for the history of political thought. Numerous political experiments have been marginalized from historical and state-building narratives as the irrelevant work of caudillos, such as the short-lived Rio Grandense Republic in southern Brazil (1836–45). By explaining the Rio Grandense caudillos’ engagement with constitutionalism, this article argues that ‘caudillo’ can be a useful category of analysis if historically contextualized. The article thus reconsiders the history of political thought and state-building in Latin America and beyond in the age of revolutions, suggesting the serious need to scrutinize ‘failed’ states and revolutions. This argument is pursued in three steps. First, the article describes shifting understandings and usages of ‘caudillo’ in nineteenth-century Brazil and neighbouring River Plate states. Second, it analyses the Rio Grandense Republic’s 1842–3 constituent assembly and the novel electoral procedures it employed. Third, it examines the never-promulgated constitutional draft produced by its assemblymen. This constitutional draft is then compared to contemporary River Plate and Brazilian constitutions and its rejection is explained through the assemblymen’s divergent understandings of constitutionalism and democracy.

HPV Vaccination Coverage in Brazil's State of Paraná: Spatial Distribution and Advances in Public Health.

Background/Objectives: To analyze the spatial distribution of HPV vaccination coverage in relation to sociodemographic variables in a state of Southern Brazil. Methods: This was an ecological, retrospective study with secondary data from the Department of Information Technology of the Unified Health System/Ministry of Health from 2015 to 2022. The cohort method was used to calculate vaccination coverage. Geographically weighted regression was used for the independent variables. Results: There was a 22.04% reduction in vaccination between the first and second doses. Coverage with the first dose of the vaccine reached 95.17% for the female population, 64.67% for the male population, and 79.57% for both sexes. In 50.62% of cities, coverage exceeded 90% for both sexes. In 80.45% of cities, the recommended coverage for females was achieved. The variable municipal performance was positively significant for the increase in vaccination coverage in 45.45% of the regions for girls, 18.18% for boys, and 36.36% for both sexes. The family health strategy variable was significant in 9.09% of the regions for girls and both sexes. The education variable showed an inverse significance for girls in 40.90%, for boys in 18.18%, and for both sexes in 36.36% of the regions. Conclusions: HPV vaccination declined between the first and second doses, with high first-dose coverage among females and moderate coverage among males. Municipal performance notably impacted coverage, particularly for girls. The family health strategy was relevant in specific regions, while educational factors had a variable effect. Addressing these variables may enhance vaccination coverage and minimize the gap between doses.

Influence of different environmental challenges on the expression of reproductive traits in Holstein cattle in Southern Brazil.

The aim of this study was to assess the impact of genotype-environment interaction (GEI) on the manifestation of traits such as age at first calving (AFC), age at first service (AFS), and calving interval (CI) through the application of the reaction norm model in Holstein cattle raised in Paraná state, Brazil. Utilizing data from the milk testing service of the Paraná Association of Holstein Cattle Breeders (APCBRH), this study analyzed records from 179,492 animals undergoing their first, second, and third lactations from the years 2012 to 2022. These animals were part of 513 herds spread across 72 municipalities in Paraná. The environmental gradient was established by normalizing contemporary group solutions, derived from the animal model, with the 305-day-corrected milk yield serving as the dependent variable. Subsequently, reaction norms were determined utilizing a Random Regression Model. Spearman's correlation was then applied to compare the estimates of breeding values across different environmental gradients for the studied traits. The highest EG (+ 4) indicates the least challenging environments, where animals experience better environmental conditions. Conversely, lower EG (-4) values represent the most challenging environments, where animals endure worse conditions. The only trait that exhibited a moderate heritability magnitude was AFC (0.23) in the least challenging environmental condition. The other traits were classified as having low heritability magnitudes regardless of the evaluated environmental gradient. While minimal evidence was found for the influence of GEI on CI, a clear GEI effect was observed for AFC and AFS across all environmental gradients examined. A reversal in genotype ranking occurred under extreme environmental conditions. The findings suggest that the best-performing genotype under one environmental gradient may not necessarily excel under another.

Isolation of Toxoplasma gondii from the masseter muscles of equines destined for human consumption in a slaughterhouse in southern Brazil

Isolation of Toxoplasma gondii from the masseter muscles of equines destined for human consumption in a slaughterhouse in southern Brazil

Human immunodeficiency virus cascade-continuum of care stages and outcomes in a hospital in southern Brazil.

The human immunodeficiency virus (HIV) continuum of care cascade illustrates the 90-90-90 goals defined by the Joint United Nations Program on HIV/acquired immunodeficiency syndrome (UNAIDS). The care cascade includes the following five steps: Diagnosis, linkage to care, retention in care, adherence to antiretroviral therapy (ART), and viral suppression. To elaborate the HIV cascade of patients diagnosed with HIV at the Nossa Senhora da Conceição Hospital (HNSC) and to determine possible local causes for the loss of patients between each step of the cascade. This retrospective cohort study included patients diagnosed with HIV infection from January 1, 2015 to December 31, 2016 and followed up until July 31, 2019. The data were analyzed by IBM SPSS software version 25, and Poisson regression with simple robust variance was used to analyze variables in relation to each step of the cascade. Variables with P < 0.20 were included in multivariable analysis, and P < 0.05 was considered significant. Pearson's χ 2 test was used to compare the groups of patients followed up at the HNSC and those followed up at other sites. The results were lower than those expected by the UNAIDS, with 94% of patients linked, 91% retained, 81% adhering to ART, and 84% in viral suppression. Age and site of follow-up were the variables with the highest statistical significance. A comparison showed that the cascade of patients from the HNSC had superior results than outpatients, with a significant difference in the last step of the cascade. The specialized and continued care provided at the HNSC was associated with better results and was closer to the goals set by the UNAIDS. The development of the HIV cascade using local data allowed for the stratification and evaluation of risk factors associated with the losses occurring between each step of the cascade.

Sediment source tracing in a Brazilian subtropical catchment using diffuse reflectance: Effect of spectral ranges, pre-processing techniques, and multivariate model

ABSTRACT Agriculture intensification in Southern Brazil’s subtropical regions combined with the frequent occurrence of erosive rainfall has rendered the area a global water erosion hotspot. In this scenario, understanding and regulating erosion processes at the river catchment scale is critical for mitigating soil and water resource degradation. Traditional methods for tracing sediment sources are expensive and time-consuming and justify the development of alternative approaches. Therefore, in this study, we employed diffuse reflectance spectroscopy analyses in the ultraviolet-visible (UV-VIS), near-infrared (NIR), and mid-infrared (MIR) ranges, combined with multivariate models and spectral pre-processing techniques to estimate sediment source contributions in a homogeneous subtropical catchment (Conceição River, 804 km²). Soil samples (n = 181) were collected to characterize the four potential sediment sources, including: cropland (n = 78), stream bank (n = 36), unpaved road (n = 40) and pasture (n = 27). Moreover, 44 sediment samples were collected, including suspended sediment (n = 8), fine sediment deposited on the riverbed (n = 15), and suspended sediment samples collected in the water column during storm events (n = 21). Vector machine (SVM) model outperformed the others, with better accuracy and reliability. While UV-VIS spectra proved less effective due to soil homogeneity across the catchment, NIR and MIR spectra provided valuable information for discriminating sediment sources. Furthermore, reducing the number of potential sources (from four to three or two) improved model predictions, especially when distinguishing between surface sources (cropland and pasture) and subsurface sources (unpaved roads and stream banks). The study’s findings shed light on the power of efficient and cost-effective alternative methods for assessing sediment sources, which are vital for promoting effective erosion control and sustainable land management in similar regions.

Radiological Protection Management: software implementation in a hospital in south Brazil

The exacerbated increase in the use of ionizing radiation to obtain images, and the risks and standards that exist to preserve the health of those who use it, are not properly taken into account when carrying out radiodiagnostic examinations. The professionals who work in these environments play a decisive role in the performance of their numerous activities within radiodiagnostic services, bearing in mind that any dose of radiation is associated with a probability of biological effects occurring, no matter how low that dose may be. Thus, the aim of building a software program was to optimize the work of the multiprofessional and interdisciplinary team in radiodiagnostic services, in the management of radiological protection. This is a methodological and quasi-experimental study carried out in a university hospital in southern Brazil, intentionally chosen because it has a Radiological Protection Committee. This research design was adopted for the development of technological production, in this case software for managing radiological protection. The study was carried out in the radiological protection sector of the radiology department of a university hospital in southern Brazil. The results showed that the software, called SisPRad - Management System for Radiological Protection, is a tool that helps the service's multi-professional and interdisciplinary team in terms of managing radiological protection. Finally, it aims to ensure the safety of professionals working in the service and its users, as well as reducing repetition of activities at management level, and can be adapted for other institutions. The computer registration number 512019002125-8 was obtained from the National Institute of Industrial Property for the first version of the software and the registration number 512023003116-0 for its second version.

Association of the rs9896052 Polymorphism Upstream of GRB2 with Proliferative Diabetic Retinopathy in Patients with Less than 10 Years of Diabetes

Growth factor receptor-bound protein 2 (GRB2) is a negative regulator of insulin signaling and a positive regulator of angiogenesis. Its expression is increased in a mouse model of retinal neovascularization and in patients with type 2 diabetes mellitus (T2DM). This case–control study aimed to investigate the association between the rs9896052 polymorphism (A&gt;C) upstream of GRB2 and proliferative diabetic retinopathy (PDR) in patients with T2DM from Southern Brazil, taking into consideration self-reported skin color (white or non-white) and the known duration of diabetes (&lt;10 years or ≥10 years). Genotypes were determined by real-time PCR in 838 patients with T2DM (284 cases with PDR and 554 controls without DR). In the total study group and in the analysis stratified by skin color, the genotype and allele frequencies were similar between cases and controls. However, among patients with less than 10 years of diabetes, the C allele was more frequent in cases than in controls (63.3% versus 51.8%, p = 0.032), and the CC genotype was independently associated with an increased risk of PDR (adjusted OR = 2.82, 95% CI 1.17–6.75). In conclusion, our findings support the hypothesis that the rs9896052 polymorphism near GRB2 is associated with PDR in Brazilian patients with T2DM.

The burden of pre-operative anaemia and postoperative outcomes in 15 166 surgical patients from a public hospital in Brazil: A retrospective cohort study.

Preoperative anaemia is associated with poor postoperative outcomes; however, few studies have reported its prevalence in developing countries and its association with significant postoperative outcomes. We aimed to identify the prevalence of anaemia and its association with postoperative outcomes in a major public hospital in Brazil. Retrospective cohort study. Single-centre, 860-bed, quaternary university-affiliated teaching hospital in Southern Brazil. We included adult patients who had undergone surgery between 2015 and 2019. Main outcome measures: The main outcome was the in-hospital 30-day postoperative mortality. According to the World Health Organisation, we defined anaemia and its sub-classification (mild, moderate, and severe). We developed Poisson regression models to examine the association between preoperative anaemia and outcomes. We included 15 166 patients, of whom 6387 (42.1%) were anaemic. After adjustment for confounding factors, patients with anaemia had an increased risk of in-hospital 30-day postoperative mortality (relative risk (RR) 1.69, 95% confidence interval (CI) 1.44 to 1.99, P < 0.001). Mild [relative risk (RR) 1.38, 95% CI 1.12 to 1.71, P = 0.003], moderate (RR 1.73, 95% CI 1.43 to 2.10, P < 0.001), and severe anaemia (RR 2.43, 95% CI 1.92 to 3.07, P < 0.001) were associated with the primary outcome. Anaemia increased the transfusion risk (RR 4.44, 95% CI 3.90 to 5.06, P < 0.001) and postoperative intensive care unit (ICU) admission (RR 1.09, 95% CI 1.04 to 1.16, P = 0.001). Four out of 10 patients had anaemia. These patients had an increased risk of adverse postoperative outcomes. Comprehension of the magnitude and impact of anaemia is essential to establish interventions in low-resource scenarios to optimise the patient's journey. Institutional Review Board Registration number 40522820000005327 (Brazilian CEP/CONEP System, available in https://plataformabrasil.saude.gov.br/).

Collective Rural Resettlement: the Vulnerabilities of Families Affected by a Hydroelectric Dam in Southern Brazil

Objective: To evaluate the ways in which affected families cope with health vulnerabilities and environmental changes after compulsory displacement, considering the Rural Collective Resettlement (RCC) service modality. Theoretical Framework: The vulnerability in health and environment proposed by José Ricardo Ayres is observed in the affected population as the chance of people being exposed to illness, taking into account the environment, individual, social and health service aspects. Method: 11 questionnaires were administered to those affected by the hydroelectric plant, who were served by the RCC modality. Results and Discussion: Subjective aspects involving the compulsory displacement of the affected population, such as the networks of social, cultural and neighborhood relations, are supplanted by the prospect of economic gains for the municipalities, based on the supposed regional development caused by the movement brought about by the start of construction and, later, by the payment of royalties to the affected municipalities. However, the losses due to profound changes, especially for the population affected, the compulsory displacement and, with it, the reduction in the local population and, consequently, the economy, are not properly accounted for. Research Implications: The RCCs are the least incentivized and most time-consuming form of care Originality/Value: The sense of belonging and identification as a community, the promotion of collective work and the organization of the health and education care network have contributed to making the health and environmental vulnerability caused by the hydroelectric dam less significant.

Aspects of the reproductive biology of sympatric Myrtaceae: &lt;i&gt;Myrceugenia euosma&lt;/i&gt; and &lt;i&gt;Siphoneugena reitzii&lt;/i&gt; in southern Brazil

Background: The Myrtaceae family represents one of the most diverse groups in South America. Yet, there are few studies on their reproductive characteristics. Among the species with limited information on their reproductive behavior are Myrceugenia euosma (O. Berg) D. Legrand and Siphoneugena reitzii D. Legrand. Questions: What are the floral attractions and resources of M. euosma and S. reitzii for pollinators? Who are the pollinators of these species? What is the predominant reproductive system in both species? Studied species: M. euosma and S. reitzii, two sympatric Myrtaceae from southern Brazil. Study site and dates: Urubici, Painel, and Rio Rufino, Santa Catarina state, southern Brazil. November 2021 - February 2022. Methods: Information was obtained on morphological aspects, anthesis time, stigmatic viability, floral resources, structures attractive to visitors, olfactory testing, observation and identification of floral visitors, and reproductive system testing. Results: The flowers of M. euosma opens between 11 am and 17 pm (- 20 pm), with full opening occurring mostly at night; S. reitzii flowers open between 4 a.m. and 6 a.m., with a highest peak by 8 a.m. Flowers of both species have receptive stigmas until senescence. Pollen is the primary floral reward and the scent coming from the anthers combined with the floral display attract native bees and Apis mellifera, legitimate pollinators of both species. The lack of fruit development in the self-pollination tests support cross reproduction in both taxa. Conclusions: Both species exhibit traits consistent with melittophily syndrome and potential self-incompatibility. These results are essential for conservation efforts.

Calibrated Eckhardt’s filter versus alternative baseflow separation methods: A silica-based approach in a Brazilian catchment

The Eckhardt’s filter, a recursive digital filter widely used in hydrology to separate baseflow, relies on two parameters: the recession constant (a) and the maximum allowable long-term ratio of baseflow to streamflow (BFImax). While a can be determined through regression analyses, BFImax is often assigned an arbitrary value because of limited catchment information for a more objective determination. This study aimed to assess and calibrate BFImax for a 1.2 km2 rural catchment in southern Brazil using dissolved silica data. Calibration involved minimizing differences between filter-generated baseflow hydrographs and those derived from dissolved silica measurements and mass balance across 13 monitored rainfall-runoff events. The calibrated model was compared to three established models: a modified graphical method based on local minima, a backward filter model, and a one-parameter filter. The results yielded an optimal BFImax of 0.653 with high model performance (PBias ≈ 0, NSE = 0.85, KGE = 0.74, and NRMSD = 13 %) against silica-derived baseflow. Applying the calibrated filter to a six-year streamflow dataset yielded a long-term baseflow index (BFI) value of 54 %, aligned with regional and global averages. Comparisons with other models showed that the backward filter model produced unrealistic baseflow values nearly identical to streamflow values; the local minima method overestimated baseflow by +19 % and failed to accurately represent the smoothness and peaks of the baseflow hydrographs; and the one-parameter filter represented the shape and timing of the baseflow hydrographs well, but underestimated magnitude by −19 %. These findings validate the effectiveness of the Eckhardt’s filter in generating accurate baseflow hydrographs and confirm the importance of calibrating BFImax for optimal performance. The research also endorses the use of dissolved silica measurements and the mass balance method as a reliable approach for calibrating BFImax for long-term assessment of baseflows.

Bio-fertilizer applications from poultry slaughterhouses in subtropical agriculture – Interactions between soil structure and nitrate dynamics

The No-till system and organic fertilization combined can be a potential strategy to avoid nutrient leaching, as the soil structure plays a crucial role in retaining them. In this study, we evaluated the influence of different rates of a bio-fertilizer made of industrial organic waste (IOW) from a poultry slaughterhouse on the percolation and stocks of nitrate in disturbed and undisturbed soil samples collected from a subtropical no-till field in southern Brazil. In an incubation experiment, we performed a percolation experiment using lysimeters and simulated rainfall for 180 days and evaluated the remaining soil nitrate stock after the incubation period. We set up a completely randomized experiment with three replicates using four IOW rates (equivalent to 0, 2, 4, and 8 Mg ha−1) and two sample types: disturbed and undisturbed soils. Using the bio-fertilizer increased nitrate mineralization from 0.77 to 1.55 kg ha−1 day−1. Overall, the IOW application increased the amount of percolated nitrate, significantly influenced by the simulated rainfall (p < 0.01). The amount of water flushed through the lysimeters was significantly higher for the disturbed soils (p < 0.05, LSD test), suggesting that the loosened structure promoted a higher water flux. No differences were observed between undisturbed and disturbed samples for nitrate percolation, implying that the amount of nitrate in the liquid soil phase may be a more critical factor in determining nitrate leaching than the water flux. The disturbed samples presented significantly higher nitrate percolation with increasing IOW rates, regardless of precipitation. Stocks in the 0–5 cm depth were 6.6 kg ha−1 higher for undisturbed samples (p < 0.05, LSD test). This result suggests preserving the soil structure can significantly increase the nitrate stocks upon IOW application.

Self-perceived oral health and happiness

In recent years, studies investigating psychological states such as happiness in individuals’ health have increased. Aim: This study investigated a possible association between self-perceived oral health and happiness in university students. Methods: This cross-sectional study was performed in a cohort of university students who entered in the 2016 academic year at the Federal University of Pelotas, located in southern Brazil. Data were collected using a self-administered questionnaire, including demographic and socioeconomic characteristics, psychosocial traits, and oral health-related questions. Happiness was measured through a question accompanied by the Faces Scale of Andrews and Whitey. Poisson regression models with robust variance were used to assess the association between the exposure variables (oral health measures) and the outcome (happiness). Results: The prevalence of happiness was 48.6%. A significant association between happiness and oral health, including satisfaction with dental appearance (PR 1.86; 95% CI 1.73-2.01), oral health-related to quality of life (PR 1.19; 95% CI 1.09-1.31), and halitosis (PR 1.10; 95% CI 1.01-1.20), was found. Conclusion: Individuals who reported dissatisfaction with dental appearance, an impact on oral health-related to quality of life, and halitosis perceived themselves as unhappy.

A Software Tool for ICESat and ICESat-2 Laser Altimetry Data Processing, Analysis, and Visualization: Description, Features, and Usage

This paper presents a web-based software tool designed to process, analyze, and visualize satellite laser altimetry data, specifically from the Ice, Cloud, and land Elevation Satellite (ICESat) mission, which collected data from 2003 to 2009, and ICESat-2, which was launched in 2018 and is currently operational. These data are crucial for studying and understanding changes in Earth’s surface and cryosphere, offering unprecedented accuracy in quantifying such changes. The software tool ICEComb provides the capability to access the available data from both missions, interactively visualize it on a geographic map, locally store the data records, and process, analyze, and explore the data in a detailed, meaningful, and efficient manner. This creates a user-friendly online platform for the analysis, exploration, and interpretation of satellite laser altimetry data. ICEComb was developed using well-known and well-documented technologies, simplifying the addition of new functionalities and extending its applicability to support data from different satellite laser altimetry missions. The tool’s use is illustrated throughout the text by its application to ICESat and ICESat-2 laser altimetry measurements over the Mirim Lagoon region in southern Brazil and Uruguay, which is part of the world’s largest complex of shallow-water coastal lagoons.

Soil, water and p losses by water erosion in soil treated with pig slurry

Pig slurry (PS) can modify the soil fertility and influence the water erosion. The aim of this research was to evaluate the effect of PS doses on the content phosphorus (P) in the soil and on water (WL) and P losses due to water erosion, in a Alfisol in southern Brazil. The treatments, totaling 0, 250, 500, and 1000 m3 ha-1 of PS applied in oats (Avena strigosa), corn (Zea mays), turnip (Raphanus sativus L.) and soybean (Glycine max), and in oat residues. Simulated rainfall (65 mm h-1 and 75 minutes) was applied three times (test -T) on corn and four T on turnip, soybean, and residues, with a simulator rotating-boom. T1 occurred one day after the application of the PS and the interval between the other T ranged from 14 to 70 days. The P in the soil was determined before and after the survey. During runoff, runoff samples were collected to determine WL and P in the water. The PS did not influence the P in the soil. The P in runoff water was 78% higher in the D1000 treatment than in D0, while the difference in total P loss was 90%. Soil P at the end of the research increased at the beginning of the research, and the content in the soil at the end of the research decreased with increasing layer depth. P loss increased with increasing water loss, while P in water increased with increasing P in the soil.

Geochemistry of fine-grained sedimentary rocks: Implications for source area, paleoweathering, paleoclimate, and provenance of the Santa Maria Formation (Triassic, Paraná Basin, Brazil)

The integration of ICP-OES, XRD, chemical analysis, and scanning electron microscopy was used to investigate the source area, weathering, paleoclimate conditions, and provenance of the siltstones of the Santa Maria Formation (Middle to Upper Triassic, Southern Brazil). This unit is regionally subdivided, from base to top, into the Passo das Tropas Member (Late Anisian–Middle Ladinian) and the Alemoa Member (Middle Ladinian–Carnian). The Chemical Index of Alteration (CIA) was calculated for both members to highlight the weathering processes of primary minerals. The CIA results indicate moderate to extreme weathering of the source rocks for the siltstones. The extreme chemical alteration observed in the Passo das Tropas siltstones (CIA = 76.97–90.83) and in the mid-section of the Alemoa Member (CIA = 87.96–89.63) suggests weathering under more humid conditions, related to an increase in paleorainfall. Paleoclimate was interpreted as semi-arid to arid, with alternating wet and dry seasons. These results align with the geochemical behavior of uranium and thorium. Samples with higher CIA values show higher Th/U ratios, indicating a shift toward a more humid climate. X-ray diffraction analysis of the fine fraction (FF < 2 μm) of the samples identified mixed-layered illite-smectite (I/S) clay minerals with minor amounts of quartz. Regarding provenance, Th/U ratios coupled with Th vs. Sc and La-Th-Sc plots, suggest an upper crustal protolith for the southern Santa Maria siltstones, consisting of uplifted rocks from the crystalline basement of the Sul-Rio-Grandense shield and sedimentary rocks of the Camaquã Basin. The Th/Sc, Sc/Th, Co/Th, and La/Sc ratios, along with the contents of Al₂O₃, SiO₂, TiO₂, Co, V, Ni, and Sc, indicate a more felsic composition for the Passo das Tropas Member. Meanwhile, the source rocks of the Alemoa Member sediments demonstrate a more mafic composition in the mid-section, transitioning to a felsic composition in the uppermost succession.

A Multi-Scale Analysis of the Extreme Precipitation in Southern Brazil in April/May 2024

Since 2020, southern Brazil’s Rio Grande do Sul (RS) State has been affected by extreme precipitation episodes caused by different atmospheric systems. However, the most extreme was registered between the end of April and the beginning of May 2024. This extreme precipitation caused floods in most parts of the state, affecting 2,398,255 people and leading to 183 deaths and 27 missing persons. Due to the severity of this episode, we need to understand its drivers. In this context, the main objective of this study is a multi-scale analysis of the extreme precipitation between 26 April and 5 May, i.e., an analysis of the large-scale patterns of the atmosphere, a description of the synoptic environment, and an analysis of the mesoscale viewpoint (cloud-top features and lightning). Data from different sources (reanalysis, satellite, radar, and pluviometers) were used in this study, and different methods were applied. The National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN) registered accumulated rainfall above 400 mm between 26 April and 5 May using 27 pluviometers located in the central-northern part of RS. The monthly volumes reached 667 mm and 803 mm, respectively, for April and May 2024, against a climatological average of 151 mm and 137 mm for these months. The maximum precipitation recorded was 300 mm in a single day on 30 April 2024. From a large-scale point of view, an anomalous heat source in the western Indian Ocean triggered a Rossby wave that contributed to a barotropic anticyclonic anomalous circulation over mid-southeastern Brazil. While the precipitant systems were inhibited over this region (the synoptic view), the anomalous stronger subtropical jet southward of the anticyclonic circulation caused uplift over RS State and, consequently, conditions leading to mesoscale convective system (MCS) development. In addition, the low-level jet east of the Andes transported warm and moist air to southern Brazil, which also interacted with two cold fronts that reached RS during the 10-day period, helping to establish the precipitation. Severe deep MCSs (with a cloud-top temperature lower than −80 °C) were responsible for a high lightning rate (above 10 flashes km−2 in 10 days) and accumulated precipitation (above 600 mm in 10 days), as observed by satellite measurements. This high volume of rainfall caused an increase in soil moisture, which exceeded a volume fraction of 0.55, making water infiltration into the soil difficult and, consequently, favoring flood occurrence.

Invasive wild boar affected feral hog skull evolution over 25 years in Brazilian Pantanal wetland

Abstract The morphological plasticity of the Sus scrofa wild–domestic species complex is evident in both free-ranging morphotypes and domestic breeds. The Brazilian Pantanal feral hog (“porco-monteiro”) evolved after a long-term feralization process and represents a significant proportion of the mammalian biomass in the region. Its coexistence with native fauna brings several ecological impacts, which are mitigated by the Brazilian Pantanal wetland vastness and resource availability. They are a local subsistence game resource but also impact crops and pastures. Around the 2000s to mid-2010s, numerous European wild boar were introduced in Brazil to fulfill a demand for gourmet meat. Wild boar was also introduced to the Brazilian Pantanal as a game species and to breed with porco-monteiro feral hogs in a commercial venture to produce an even more exotic meat. The craze for wild boar meat has since dwindled, but their populations remain widespread and uncontrolled. Moreover, the full impact of the wild boar introduction on feral hog populations is still unknown. This study analyzes the skulls of porco-monteiro feral hogs from the 1990s, 2000s, and 2010s to assess possible morphological and functional variations along with skulls of wild boar and hybrids from Argentina, Uruguay, and Southern Brazil. The results indicate a trend of broadening of feral hog skulls at the coronal plane and a progressive reduction of the semispinalis capitis muscle scars over the decades. Biomechanical analysis denoted a decrease in head-elevation force that could affect the rooting performance of the latest feral hog morphotypes. Taken together, results show that wild boars likely influenced the evolution of the Pantanal feral hog skull. The magnitude of ecomorphological implications of these morphofunctional changes is unknown, as well as its effects in the Brazilian Pantanal wetland ecology.