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For the development of efficient management and conservation strategies for wild rodent species, understanding the aspects related to their reproduction, including the interaction of this physiological function with the environment, is essential. This study aimed to evaluate the impacts of weather changes derived from a semiarid region's dry and rainy seasons on the epididymal sperm characteristics of red-rumped agouti (Dasyprocta leporina), a histricognath rodent, still little studied, which inhabits the Brazilian Caatinga. The sperm from the epididymal cauda of 14 agoutis were collected, seven individuals per season (dry and rainy). Samples were evaluated for kinetic parameters, membrane structural and functional integrity, mitochondrial activity, morphology, and morphometry. The environmental variables were measured: maximum air temperature, relative humidity, wind speed, solar radiation, and the total rainfall for dry and rainy seasons were, respectively, 36.2 and 34.1 °C, 66.8 and 80.1%, 4.0 and 1.9 m/s, 527.3 and 441.8 W/m2, and 0.2 and 517.7 mm. There were strong correlations between some sperm parameters and environmental variables, mainly those related to the acquisition of sperm mobility. Sperm concentration and the number of sperm collected were higher in the dry (1028.7 sperm/mL × 106 and 1361.2 × 106 sperm) than in the rainy season (758.9 sperm × 106/mL and 714.6 sperm × 106). During the rainy season, there were fewer sperm defects, higher sperm metrics, and higher membrane structural integrity with mitochondrial activity. Regarding motility patterns, the increases during the rainy season stand out in total and progressive motility, VAP, VSL, VCL, and subpopulations of rapid sperm. In summary, our results suggest that the adverse climatic conditions of the dry season in the semiarid region, mainly high solar radiation and temperature, considerably impair the epididymal sperm quality of red-rumped agoutis. On the contrary, the largest amount of sperm was obtained during this season, probably due to compensatory and adaptive mechanisms of the species to enable its reproduction throughout the year.

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Research into microbial interactions during coffee processing is essential for developing new methods that adapt to climate change and improve flavor, thus enhancing the resilience and quality of global coffee production. This study aimed to investigate how microbial communities interact and contribute to flavor development in coffee processing within humid subtropical climates. Employing Illumina sequencing for microbial dynamics analysis, and high-performance liquid chromatography (HPLC) integrated with gas chromatography-mass spectrometry (GC-MS) for metabolite assessment, the study revealed intricate microbial diversity and associated metabolic activities. Throughout the fermentation process, dominant microbial species included Enterobacter, Erwinia, Kluyvera, and Pantoea from the prokaryotic group, and Fusarium, Cladosporium, Kurtzmaniella, Leptosphaerulina, Neonectria, and Penicillium from the eukaryotic group. The key metabolites identified were ethanol, and lactic, acetic, and citric acids. Notably, the bacterial community plays a crucial role in flavor development by utilizing metabolic versatility to produce esters and alcohols, while plant-derived metabolites such as caffeine and linalool remain stable throughout the fermentation process. The undirected network analysis revealed 321 interactions among microbial species and key substances during the fermentation process, with Enterobacter, Kluyvera, and Serratia showing strong connections with sugar and various volatile compounds, such as hexanal, benzaldehyde, 3-methylbenzaldehyde, 2-butenal, and 4-heptenal. These interactions, including inhibitory effects by Fusarium and Cladosporium, suggest microbial adaptability to subtropical conditions, potentially influencing fermentation and coffee quality. The sensory analysis showed that the final beverage obtained a score of 80.83 ± 0.39, being classified as a specialty coffee by the Specialty Coffee Association (SCA) metrics. Nonetheless, further enhancements in acidity, body, and aftertaste could lead to a more balanced flavor profile. The findings of this research hold substantial implications for the coffee industry in humid subtropical regions, offering potential strategies to enhance flavor quality and consistency through controlled fermentation practices. Furthermore, this study contributes to the broader understanding of how microbial ecology interplays with environmental factors to influence food and beverage fermentation, a topic of growing interest in the context of climate change and sustainable agriculture.

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The alarming increase in extreme weather events, such as severe storms with torrential rain and strong winds, is a direct result of climate change. These events have led to discernible shifts in forest structure and the carbon cycle, primarily driven by a surge in tree mortality. However, the impacts caused by these severe storms on the production and carbon increment from coarse woody debris (CWD) are still poorly understood, especially in the Brazilian Atlantic Forest. Thus, the goal proposed by the study was to quantify the CWD volume, necromass, and carbon stock before and after the occurrence of a severe storm and to determine the importance of spatial, structural, and qualitative variables of trees in the CWD carbon increment. The increase in carbon by the storm was 2.01 MgC ha-1, with a higher concentration in the CWD less decomposed and smaller diameter class. The forest fragment plots showed distinct increments (0.05-0.35 MgC), being influenced by spatial (elevation, declivity, and slope angle) structural (basal area) and qualitative factors (trunk quality and tree health), intrinsic to the forest. Thus, it is concluded that severe storms cause a large increase in carbon in CWD, making it essential to understand the susceptibility of forests to the action of intense rains and strong winds to model and monitor the future impacts of these extreme weather events on Atlantic Forest and other tropical forests in the world.

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The proliferation of Raphidiopsis raciborskii blooms has sparked concerns regarding potential human exposure to heightened saxitoxins (STXs) levels. Thus, comprehending how environmental elements drive the proliferation of this STXs-producing species can aid in predicting human exposure risks. This study aimed to explore the link between cyanobacteria R. raciborskii, STXs cyanotoxins, and environmental factors in 37 public supply reservoirs in the tropical region and assess potential health hazards these toxins pose in the reservoir waters. A Structural Equation Model was used to assess the impact of environmental factors (water volume and physical and chemical variables) on R. raciborskii biomass and STXs levels. Furthermore, the potential risk of STXs exposure from consuming untreated reservoir water was evaluated. Lastly, the cumulative distribution function (CDF) of STXs across the reservoirs was computed. Our findings revealed a correlation between R. raciborskii biomass and STXs concentrations. Total phosphorus emerged as a critical environmental factor positively influencing species biomass and indirectly affecting STXs levels. pH significantly influenced STXs concentrations, indicating different factors influencing R. raciborskii biomass and STXs. Significantly, for the first time, the risk of STXs exposure was gauged using the risk quotient (HQ) for untreated water consumption from public supply reservoirs in Brazil's semi-arid region. Although the exposure risks were generally low to moderate, the CDF underscored the risk of chronic exposure due to low toxin concentrations in over 90% of samples. These outcomes emphasize the potential expansion of R. raciborskii in tropical settings due to increased phosphorus, amplifying waterborne STXs levels and associated intoxication risks. Thus, this study reinforces the importance of nutrient control, particularly phosphorus regulation, as a mitigation strategy against R. raciborskii blooms and reducing STXs intoxication hazards.

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Dengue is a vector borne disease caused by virus serotypes DENV-1, DENV-2, DENV-3, and DENV-4, representing a significant public health concern in the Region of the Americas (2,997,097 cases in 2023). This study explores the relationship between dengue incidence and climate changes in the city of São Paulo-Brazil. During the first semester of 2023, Brazil reported the highest number of dengue cases in Americas' Region. Our data reveals a correlation between the high temperature and rainfall season persistence and the extension of dengue incidence into the winter season. The findings highlight the importance of understanding the relationship between climate change and disease transmission patterns to develop effective strategies for prevention and control.

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BACKGROUND: Crop yields have been affected by many different biotic and abiotic factors. Generally, plants experience more than one stress during their life cycle, and plants can tolerate multiple stresses and develop cross-tolerance. The expected rise in atmospheric CO2 concentration ([CO2]) can contribute to cross-tolerance. Priming is a strategy to increase yield or to maintain yield under stress conditions. Thus, our objective was to evaluate if priming the rice plants with water deficit during the vegetative stage can induce tolerance to heat stress at anthesis and to evaluate the contribution of e[CO2]. METHODS: The experiment was arranged in a completely randomized design in a factorial arrangement. Factor A consisted of the following treatments: water deficit at four-leaf stage (no-stress, and drought stress), heat at anthesis (normal temperature, high temperature), and priming with water deficit at four-leaf stage and heat stress at anthesis; and Factor B was two [CO2] treatments: a[CO2] = 400 ± 40 µmol mol-1 and e[CO2] = 700 ± 40 µmol mol-1. We assessed the effect of the treatments on plant growth, yield, biochemical, and transcriptome alterations. RESULTS: Although e[CO2] affected rice growth parameters, it did not affect the priming effect. Primed plants showed an increase in yield and number of panicles per plant. Primed plants showed upregulation of OsHSP16.9A, OsHSP70.1, and OsHSP70.6. These results showed induced cross-tolerance. CONCLUSIONS: Water deficit at the rice vegetative stage reduces the effect of heat stress at the reproductive stage. Water deficit at the vegetative stage can be used, after further testing in field conditions, to reduce the effect of heat stress during flowering in rice.

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The Caribbean fruit fly, Anastrepha suspensa (Lower, 1862) (Diptera: Tephritidae), is a pest of significant economic importance in Central America and Florida (USA). This study was carried out to examine the influence of climate change on the space-time distribution of A. suspensa on temporal and spatial scales. The CLIMEX software was used to model the current distribution and for climate change. The future distribution was performed using two global climate models (GCMs), CSIRO-Mk3.0 (CS) and MIROC-H (MR), under the emission scenarios (SRES) A2 and A1B for the years 2050, 2080, and 2100. The results indicate a low potential for global distribution of A. suspensa in all scenarios studied. However, tropical areas were identified with high climatic suitability for A. suspensa in South America, Central America, Africa, and Oceania until the end of the century. Projections of areas with climatic suitability for A. suspensa can provide helpful information to develop preventive strategies of phytosanitary management avoiding economic impacts with the introduction of the species.

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Low rainfall in Northeast Brazil is a limiting factor for animal production. Forages that present crassulacean acid metabolism, such as forage cactus, are adapted to the edaphoclimatic conditions of this region, as they lose little water through the stomata. Thus, the objective was to evaluate the physical and chemical quality, fatty acid profile and sensory acceptance of the meat from goats fed forage cactus as a substitute for Tifton 85 hay. Twenty-one uncastrated mixed-breed goats with a mean body weight of 18 ± 0.86 kg and 7 ± 1 months of age were used. A completely randomized design with three treatments and seven replications per treatment was performed. The inclusion of 0 (control), 25 and 55% of forage cactus in substitution of Tifton 85 hay in the diet of the goats was evaluated. The lipid content in the meat of animals fed 25 and 55% of forage cactus was 1.33% and 1.26%, respectively, and was lower (p < 0.05) in relation to the meat of animals that received the control diet (1.56%). The inclusion of 55% of forage cactus provided an increase (p < 0.05) in the content of monounsaturated fatty acids in the meat (52.71%) in relation to the control meat (37.75%). Sensory analysis differed (p < 0.05) between treatments. We recommend replacing Tifton 85 hay with 55% forage cactus, as it presents greater sensory acceptance, and provides lower lipid content and higher content of monounsaturated fatty acids in goat meat.

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Climate change can alter the toxic effects of pesticides on soil invertebrates. However, the nature and magnitude of the influence of climatic factors on clothianidin impacts in tropical soils are still unknown. The influence of increasing atmospheric temperature and the reduction in soil moisture on the toxicity and risk of clothianidin (seed dressing formulation Inside FS®) were assessed through chronic toxicity tests with collembolans Folsomia candida in a tropical field soil (Entisol). The risk of clothianidin for collembolans was estimated using the Toxicity-Exposure Ratio (TER) approach. Organisms were exposed to increasing clothianidin concentrations at 20, 25 and 27 °C in combination with two soil moisture conditions (30 and 60% of the maximum water holding capacity-WHC). The effect of temperature and soil moisture content on clothianidin toxicity was verified through the number of F. candida juveniles generated after 28 days of exposure to the spiked soil. The toxicities estimated at 25 °C (EC50_30%WHC = 0.014 mg kg-1; EC50_60%WHC = 0.010 mg kg-1) and 27 °C (EC50_30%WHC = 0.006 mg kg-1; EC50_60%WHC = 0.007 mg kg-1) were 2.9-3.0-fold (25 °C) and 4.3-6.7-fold (27 °C) higher than those found at 20 °C (EC50_30%WHC = 0.040 mg kg-1; EC50_60%WHC = 0.030 mg kg-1), indicating that clothianidin toxicity increases with temperature. No clear influence of soil moisture content on clothianidin toxicity could be observed once the EC50 values estimated at 30% and 60% WHC, within the same temperature, did not significantly differ. A significant risk was detected in all temperatures and soil moisture scenarios studied, and the TER values indicate that the risk can increase with increasing temperatures. Our results revealed that temperature could overlap with soil moisture in regulating clothianidin toxicity and reinforce the importance of including climatic factors in the prospective risk assessment of pesticides.

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The search for productive germplasm adapted to adverse conditions is an important action to mitigate the harmful effects of climate change. The aim was to identify the yield potential of 50 popcorn inbred lines grown in field conditions, in two crop seasons (CS), and under contrasting water conditions (WC). Morphoagronomic, physiological, and root system traits were evaluated. Joint and individual analyses of variance were performed, in addition to the multivariate GT bip-lot analysis. Expressive reductions between WC were observed in 100-grain weight (100 GW), popping expansion (PE), grain yield (GY), expanded popcorn volume per ha (EPV), row number per ear (RNE), plant height (PH), relative chlorophyll content (SPAD), and nitrogen balance index (NBI). It was found that the SPAD, 100 GW, GY, PE, and grain number per ear (GNE) traits had the most significant impact on the selection of genotypes. Regardless of WC and CS, the ideal lines were L294 and L688 for PE; L691 and L480 for GY; and L291 and L292 for both traits. SPAD, 100 GW, and GNE can contribute to the indirect selection. Our work contributes to understanding the damage caused by drought and the integration of traits for the indirect selection of drought-tolerant popcorn genotypes.

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We assessed the potentially pathogenic fungi present in Antarctic permafrost and the overlying active layer on King George, Robert, Livingston and Deception Islands in the South Shetland Islands archipelago, maritime Antarctica. Permafrost and active layer sub-samples were incubated at 37 °C to select fungi able to grow inside the human body. A total of 67 fungal isolates were obtained, 27 from the permafrost and 40 from the active layer. These represented 18 taxa of the genera Alternaria, Aspergillus, Curvularia, Penicillium, Rhodotorula and Talaromyces. The majority of fungi detected occurred exclusively either in the permafrost or the active layer at each site. Only Aspergillus thermomutatus, Penicillium cf. chrysogenum and Rhodotorula cf. mucilaginosa were present in both permafrost and active layer samples from the same site. The yeast R. cf. mucilaginosa was recovered from both in at least two sites. The genus Penicillium was the most abundant and widely distributed genus in both permafrost and active layer samples across the sites sampled. All fungal isolates were screened using enzymatic, pH and antifungal assays to identify their virulence potential. Aspergillus hiratsukae, A. thermomutatus and R. cf. mucilaginosa, known human opportunistic fungi, were identified, displayed phospholipase, esterase, proteinase and hemolytic activities. All three also displayed the ability to grow at 40°, 45° and/or 50 °C and resistance to fluconazole and itraconazole; additionally, R. cf. mucilaginosa showed resistance to amphotericin B and viability after 100 d at -80 °C. A. thermomutatus UFMGCB 17415 killed the entire larvae of Tenebrio molitor in six days and R. cf. mucilaginosa UFMGCB 17448 and 17473 in three and four days, respectively. The melting of maritime Antarctic permafrost as a result of climate change may threaten the release of wild strains of pathogenic fungi geographically isolated for long time, which may in turn be transported within and beyond Antarctica by different biological and non-biological vectors.

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INTRODUCTION: The Anthropocene is used to describe the most recent period where major disruptions in Earth's system processes have resulted from humanity's increasing ecological footprint. Climate change affects the social and environmental determinants of good health, such as clean air, stable ecosystems, safe drinking water, and sufficient and safe food, and they seem to be closely related to air pollution. OBJECTIVES: This article aims to review the evidence of how extreme weather events and indoor and outdoor pollution are associated with insufficient lung growth in early life, changes in lung function, and the increase in respiratory infections, favoring the development of allergic respiratory diseases. MATERIAL AND METHODS: Non-systematic review of English, Spanish, and Portuguese articles published in the last ten years in databases such as PubMed, EMBASE, and SciELO. The terms used were air pollution OR climate changes OR smoke, AND health OR allergic disease. RESULTS: Climate change and air pollution are the leading contributors to health emergencies around the world. On a global scale, those most at risk of adverse health effects associated with climate change include children, the elderly, and other vulnerable groups. Climate change and air pollution have adverse impacts on respiratory allergies, and the mechanisms are complex and interactive. CONCLUSION: Health professionals must receive information and education necessary to establish effective mitigation and adaptation strategies to minimize the effects of climate changes on the respiratory health of their patients.

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This study evaluated carbon dynamics in a carbonate microbasin (Bule stream), located in an important metallogenetic area (QF) in Brazil. River water collections were performed on a base and high flow. The microbasin showed high DIC, with HCO3- being the main component, followed by CO2. The pCO2 showed high values, indicating fluxes in the water → air direction. The degassing was 683.4 mmol m-2 day-1 (average at low flow) and 43.4 mmol m-2 day-1 (average at high flow). The fluvial flow was 9 to 31 kg km-2 day-1 of HCO3- and 1.4 to 0.7 kg km-2 day-1 of CO2, respectively, at the base and high flow. Considering the importance of the lithological unit of the Minas Supergroup for the QF, the total flow of CO2 released by all the basins that compose such units was estimated. The estimated values were 1.3 × 1012 mmol day-1 in low flow and 8.4 × 1010 mmol day-1 in high flow. The data obtained in this study were the first in the QF region. The Bule stream is an environmental protection area, free from contamination, considered a background for other drainage basins inserted in the QF. The results obtained reinforce the importance of hydrographic microbasins influence on the river carbon fluxes in a regional and global context.

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Histoplasmosis is a mycotic infection principally affecting pulmonary tissue; sometimes, histoplasmosis can progress into a systemic disease. This infection involves immunocompetent and immunosuppressed human and other mammalian hosts, depending on particular circumstances. Histoplasmosis infection has been documented worldwide. The infection is acquired by inhaling infective mycelial propagules of the dimorphic fungus Histoplasma capsulatum. New reports of clinical cases of histoplasmosis in extreme latitudes could be related to human social adaptations and climate changes in the world, which are creating new favorable environments for this fungus and for bats, its major natural reservoirs and dispersers. Histoplasma has been isolated from most continents, and it is considered a complex of cryptic species, consisting of various groups of isolates that differ genetically and correlate with a particular geographic distribution. Based on updated studies, Histoplasma taxonomy is adjusting to new genetic data. Here, we have suggested that Histoplasma has at least 14 phylogenetic species distributed worldwide and new genotypes that could be under deliberation. Histoplasma's geographic radiation began in South America millions of years ago when the continents were joined and the climate was favorable. For fungal spreading, the role of bats and some birds is crucial, although other natural factors could also participate.

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Resumo A interface entre as Mudanças Climáticas e a Segurança Alimentar e Nutricional (SAN) tem se destacado na agenda de desenvolvimento sustentável desde o início da década de 1990. Desde então, estudos demonstram que as mudanças climáticas possuem efeitos negativos na SAN, potencializados pela pobreza e desigualdade social. O objetivo deste artigo é realizar uma revisão relacionando mudanças climáticas e SAN. A pesquisa foi realizada no PubMed utilizando os descritores "climate change and food security" no título, selecionando somente artigos em português, espanhol e inglês e com relação direta com os temas. Os principais impactos das mudanças climáticas na SAN foram no acesso, produção, qualidade nutricional e volatilidade dos preços dos alimentos. Estratégias de mitigação/adaptação aos efeitos das mudanças climáticas na SAN também foram apontadas nos estudos, além de um panorama geográfico das publicações com domínio de estudos na África e Ásia, continentes marcados por desigualdade social e pobreza. As mudanças climáticas afetam as dimensões da SAN, especialmente em populações mais pobres e em situação de desigualdade social. A relevância dos temas suscita a premência de maior investimento em políticas públicas, estudos e pesquisas acerca da temática no mundo.

Abstract The interface between Climate Changes and Food and Nutrition Security (FNS) has been standing out in the sustainable development agenda since the early 1990's. Since then, studies show that climate changes have negative effects on the FNS, aggravated by poverty and social inequality. The purpose of this paper is to perform a review evidencing the relationships between climate changes and FNS. The research was carried out in PubMed using the descriptors "climate change and food security" on the headline, selecting only papers in Portuguese, Spanish, and English languages, and with a direct relation to the themes. The main impacts of climate changes on the FNS were related to the access, production, nutritional quality, and volatility of food prices. The studies also indicated mitigation/adaptation strategies to the effects of climate changes on the FNS, as well as a geographic panorama of the publications with fields of study in Africa and Asia, continents marked by social inequality and poverty. Climate changes affect the dimensions of FNS, especially in poorer populations in situation of social inequality. The relevance of the themes raises concern on the urgency of higher investments in public policies, studies, and research on the subject around the world.

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Resumen En el presente trabajo se analiza la distribución de las especies peruanas del género Senecio, a partir de 4342 pliegos de herbario con localidades y coordenadas geográficas disponibles. Para conocer cómo están relacionadas con el clima se usó el método de los pisos bioclimáticos de Rivas-Martínez, y el modelo de Koppen-Geiger para observar su comportamiento frente a cambios climáticos a 50 y 100 años. Para observar cómo es la distribución departamental de las especies y la relación entre departamentos en cuanto a su presencia-ausencia, se recurrió a un clúster (UPGMA, coeficiente de Sorensen). Un Análisis de Componentes Principales (ACP) reveló la correlación de cada especie con la altitud media, variables climáticas medias e Índice de Termicidad medio de las localidades de una especie, estableciendo 10 grupos ordenados por pisos bioclimáticos. Diferentes modelos de distribución fueron cartografiados correspondiéndose con pisos bioclimáticos y provincias biogeográficas del Perú. La Cordillera Blanca se configura como una auténtica barrera biogeográfica separando numerosas localidades del N del Perú del resto de las posiciones de Senecio.

Abstract This paper analyses the distribution of Peruvian species of the genus Senecio, based on 4342 herbarium sheets with available localities and geographical coordinates. The Rivas-Martínez method of bioclimatic belts and the Koppen-Geiger model were used to determine how they are related to climate, and to observe their response in the face of climatic changes over 50 and 100 years. To observe the departmental distribution of the species and the relationship between departments in terms of presence-absence (UPGMA, Sorensen's coefficient) was used. A Principal Component Analysis (PCA) revealed the correlation of each species with mean altitude, mean climatic variables and mean Thermicity Index of the localities of a species, establishing 10 groups ordered by bioclimatic belts. Different distribution patterns were mapped, corresponding to bioclimatic belts and biogeographical provinces of Peru. The Cordillera Blanca forms an authentic biogeographical barrier separating numerous localities in northern Peru from the rest of the Senecio positions.

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Abstract Frequent heat waves and mass mortality events on marine biota are positively correlated to ocean warming. Although literature has indicated some species of marine sponges, and some oceanic regions, like the Brazilian Exclusive Economic Zone, may be less affected or seem to be more resilient under future scenarios of climate changes, few studies have focused on the species responses on the climate change issue along Brazilian coast. This paradigm was undone throughout 2019 after an exceptional average increase of 2 °C in the sea surface temperature (SST) and on precipitation values since 2015 at Ilha Grande Bay (IGB, SE Brazil). The combination of SST and precipitation average increase possibly favored an environmental context for the unprecedented strong population decline and mass mortality rate of the marine sponge species Desmapsamma anchorata in the austral spring. The species used to be one of the most frequent benthic species at IGB however it was only recorded in 41.7% sites (n = 12). From 162 individuals recorded at Abraãozinho along 180 m rocky shore, 83 individuals (51.2%) were healthy, 74 (45.7%) were intensively covered by cyanobacteria and locally bleached, and five (3.1%) were completely bleached or died. Desmapsamma anchorata population deterioration in a biogeographic transition zone (Rio de Janeiro state) may reflect a shift in the marine community of IGB, opening space for opportunistic species establishment and coverage increase, since IGB has a high species turnover. The three-dimensionality, the shelter for several species, the high competitive ability and the potential to indicate polluted or not polluted areas make D. anchorata a key species for IGB monitoring in a climate change scenario.

Resumo Ondas de calor e eventos de mortalidade em massa da biota marinha são cada vez mais frequentes e estão positivamente correlacionados ao aquecimento do oceano. Embora a literatura tenha indicado que algumas espécies de esponjas marinhas e algumas regiões oceânicas, como a Zona Econômica Exclusiva do Brasil, podem ser menos afetadas ou serem mais resilientes em cenários futuros de mudanças climáticas, poucos estudos focaram na resposta das espécies à problemática das mudanças climáticas na costa brasileira. Esse paradigma foi desfeito em 2019 após um excepcional aumento médio de 2 °C na temperatura da superfície do mar e nos valores de precipitação, desde 2015 na Baía da Ilha Grande (BIG, SE Brasil). Essa combinação de fatores possivelmente favoreceu um contexto ambiental sem precedentes, levando ao forte declínio populacional e alta taxa de mortalidade da esponja marinha Desmapsamma anchorata na primavera austral. A espécie costuma ser uma das espécies bentônicas mais frequentes na BIG, mas só foi observada em 41,7% dos sítios (n = 12). De 162 indivíduos registrados em Abraãozinho ao longo de 180 m de costão rochoso, 83 indivíduos (51,2%) estavam saudáveis, 74 (45,7%) estavam cobertos por cianobactéria e localmente branqueados e cinco (3,1%) estavam completamente branqueados ou mortos. A deterioração da população de D. anchorata na zona de transição biogeográfica (estado do Rio de Janeiro) pode refletir em uma alteração na comunidade marinha da BIG, abrindo espaço para o estabelecimento de espécies oportunistas, uma vez que a BIG possui alto turnover. A tridimensionalidade, o abrigo a diversas espécies, a alta capacidade competitiva e o potencial de indicar áreas poluídas ou não tornam D. anchorata uma espécie chave no monitoramento da BIG em um cenário de mudanças climáticas.

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ABSTRACT Background: This research addresses two questions: (1) how El Niño Southern Oscillation (ENSO) affects climate variability and how it influences dengue transmission in the Metropolitan Region of Recife (MRR), and (2) whether the epidemic in MRR municipalities has any connection and synchronicity. Methods: Wavelet analysis and cross-correlation were applied to characterize seasonality, multiyear cycles, and relative delays between the series. This study was developed into two distinct periods. Initially, we performed periodic dengue incidence and intercity epidemic synchronism analyses from 2001 to 2017. We then defined the period from 2001 to 2016 to analyze the periodicity of climatic variables and their coherence with dengue incidence. Results: Our results showed systematic cycles of 3-4 years with a recent shortening trend of 2-3 years. Climatic variability, such as positive anomalous temperatures and reduced rainfall due to changes in sea surface temperature (SST), is partially linked to the changing epidemiology of the disease, as this condition provides suitable environments for the Aedes aegypti lifecycle. Conclusion: ENSO may have influenced the dengue temporal patterns in the MRR, transiently reducing its main way of multiyear variability (3-4 years) to 2-3 years. Furthermore, when the epidemic coincided with El Niño years, it spread regionally and was highly synchronized.

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Changes in temperature resulting from climate change can impact the distribution and survival of species, including bees, where temperature may also affect their immune system. Evaluation of immune system activity is often performed by the total count of circulating hemocytes in the hemolymph. However, there are few studies on bees examining the relationship between the amount of circulating hemocytes and temperature. This study evaluated changes of circulating hemocytes in Apis mellifera hemolymph at different temperatures and development stages. Total hemocytes of bees were determined at - 8, 16, 24, and 32 °C - and at different development stages - in vivo larvae, in vitro larvae, newly emerged, and forager bees. A. mellifera larvae had a greater number of circulating hemocytes compared to the other development stages (newly emerged and foragers). Additionally, temperature was an important factor explaining variation of circulating hemocytes in the hemolymph, according to principal component analyses (PCA), as the number of circulating hemocytes was greater at higher temperatures. Therefore, extreme events arising from climate change, such as variation in temperature, can directly impact the immune system of bees, both individually and at the colony level, threatening the distribution and survival of several species.

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