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Drylands soils worldwide are naturally colonized by microbial communities known as biocrusts. These soil microbiomes render important ecosystem services associated with soil fertility, water holding capacity, and stability to the areas they cover. Because of the importance of biocrusts in the global cycling of nutrients, there is a growing interest in describing the many microbial configurations these communities display worldwide. However, comprehensive 16S rRNA genes surveys of biocrust communities do not exist for much of the planet: for example, in the continents of South America and the northern part of Africa. The absence of a global understanding of biocrust biodiversity has lead us to assign a general importance to community members that may, in fact, be regional. Here we report for the first time the presence of biocrusts in Colombia (South America) through 16S rRNA genes surveys across an arid, a semi-arid and a dry subtropical region within the country. Our results constitute the first glance of the Bacterial/Archaeal communities associated with South American biocrust microbiomes. Communities where cyanobacteria other than Microcoleus vaginatus prevail, despite the latter being considered a key species elsewhere, illustrate differentiable results in these surveys. We also find that the coastal biocrust communities in Colombia include halo-tolerant and halophilic species, and that niche preference of some nitrogen fixing organisms deviate from previously described global trends. In addition, we identified a high proportion (ranging from 5 to 70%, in average) of cyanobacterial sequences that did not match any formally described cyanobacterial species. Our investigation of Colombian biocrusts points to highly diverse communities with climatic regions controlling taxonomic configurations. They also highlight an extensive local diversity to be discovered which is central to better design management and restoration strategies for drylands soils currently undergoing disturbances due to land use and global warming. Finally, this field study highlights the need for an improved mechanistic understanding of the response of key biocrust community members to changes in moisture and temperature.

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In the present study we aimed to investigate superficial skin temperature of racehorses' distal limbs after training in a racetrack. Male and female Thoroughbred racehorses were investigated in summer, after light training, and in the winter, after light and intense training. Horses were exercised (Exercise group, EG) under trainers' protocol while others were maintained inside their stalls (Control group, CG). Thermographic images were obtained from the front (fetlock, cannon, and carpus) and hindlimbs (fetlock, cannon, and tarsus), before exercise and 45, 60, 120 and 180 min after exercising. Images were analyzed using the Flir Tools® program. Temperatures of different moments of each group were compared using Anova for repeated measures and each moment of EG versus CG using Student t test. Horses of the CG maintained steady temperature in the winter, but in summer temperature increased at M45 until M180 (P < 0,01). EG increased temperatures after exercises that remained higher than M0 even at 180 min post-exercise (P < 0,0001), for most of the regions in winter and summer. EG temperatures were higher than CG at most of the time points after exercise. There was positive correlation between all regions' temperature and the atmospheric temperature for the CG during the summer (P = 0,003, r2 = 0,9622), observed for the front fetlock and carpal regions for the EG (P = 0.035, r2 = 0,8166). This pilot study demonstrates that, after race exercising under natural conditions skin temperature might take more than 180 min to return to basal values.

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The pelagic cephalopod species jumbo flying squid Dosidicus gigas is ecologically and economically important in the Humboldt ecosystem off Peru. This squid species is sensitive to oceanic environmental changes, and regional oceanographical variability is one of the important factors driving its redistribution. Off Peruvian waters, mesoscale eddies are ubiquitous and dominate the biogeochemical processes in this region. This study first explored the role of mesoscale eddies in regulating the environments and their effects on the abundance and habitat distribution of D. gigas off Peru by analyzing squid distribution in eddy-centric coordinates and building a habitat suitability index (HSI) model. Results indicated that the abundance and habitat distribution of D. gigas in mesoscale eddies varied across months, with significant differences observed between anticyclonic eddies (AE) and cyclonic eddies (CE). In AE, a higher abundance and proportion of suitable habitat occurred. While in CE, the abundance was relatively low and the suitable habitat was relatively less, concentrating at the periphery of CE. Based on the HSI model results, sea surface temperature (SST) and 50 m water temperature (T50m) in AE were more favorable for D. gigas, which was 0.3-0.5 °C lower than that in CE, yielding high-quality habitats and higher abundance of D. gigas. Our findings emphasized that mesoscale eddies have a significant impact on water temperature conditions and nutrient concentrations off Peruvian waters.

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A short stretch (27°S and 30°S) along the coast of Chile is habitat for the seagrass Heterozostera nigricaulis. The seagrass is classified as endangered and grows only clonally, but there are no data on its physiology and growth. However, this information is important to gain insights into its acclimation potential and how disturbances may affect them. We therefore studied H. nigricaulis at 27° and 30°S, and determined their growth and physiology among seasons and depths over one year. Biomass was higher at 27° than at 30°S, and was always higher in summer than in autumn and winter. Increased photosynthesis supported growth in summer, and in winter carbonic anhydrase activity was in place to maintain these evergreen meadows. Our results suggest that these seagrass meadows are adapted to local conditions, which, together with their asexual reproduction, could make them more vulnerable to disturbance. Therefore, our results serve as a basis for future studies on seagrass growth dynamics, and are important for protection and management plans.

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The increasing need for fresh water in a climate change scenario requires remote monitoring of water bodies in high-altitude mountain areas. This study aimed to explore the feasibility of SMFC operation in the presence of low dissolved oxygen concentrations for remote, on-site monitoring of physical environmental parameters in high-altitude mountainous areas. The implemented power management system (PMS) uses a reference SMFC (SMFCRef) to implement a quasi-maximum power point tracking (quasi-MPPT) algorithm to harvest energy stably. As a result, while transmitting in a point-to-point wireless sensor network topology, the system achieves an overall efficiency of 59.6%. Furthermore, the control mechanisms prevent energy waste and maintain a stable voltage despite the microbial fuel cell (MFC)'s high impedance, low time response, and low energy production. Moreover, our system enables a fundamental understanding of environmental systems and their resilience of adaptation strategies by being a low-cost, ecological, and environmentally friendly alternative to power-distributed and dynamic environmental sensing networks in high-altitude mountain ecosystems with anoxic environmental conditions.

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The fall armyworm [FAW; Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)], is considered a serious invasive pest that poses a serious threat to world food security. It can completely devastate a whole country's cereal crops. Therefore, the present work is the 1st field trial in Egypt to elucidate some ecological aspects of S. frugiperda on maize plants (Single-Hybrid 168 Yellow Corn cultivar) at Esna district, Luxor Governorate, Egypt, throughout two sequential growing seasons of maize (2021-2022). Three insect parameters were used, i.e., egg masses, number of larvae, and percentage of damaged corn plants. Effects of certain climatic conditions and corn plant ages on S. frugiperda seasonal activity and damaged plants percentage were also estimated. S. frugiperda population initiated to attack maize plants from the 3rd week of June until the harvest in every season. S. frugiperda had two seasonal activity peaks in terms of egg masses numbers and three peaks regarding the larval population density/season. Its damage percentage increased with increasing plant age weekly. The mean of S. frugiperda egg masses were 2.83 ± 0.40 and 2.96 ± 0.45 mass /10 corn plants in 2021 and 2022, respectively. While, the overall mean larval populations were 13.41 ± 0.52 and 13.03 ± 0.46 larvae/10 plants, during the two growing seasons, respectively. Corn plant damage percentages reached 68.54 ± 2.71 and 60.42 ± 2.92% in 2021 and 2022, respectively. The combined effects of both the weather conditions and maize plant ages were highly significant on egg masses, larvae population density, and damage percentage, and varied from one season to another. The mean daily maximum temperature was the most effective variable on egg masses and the larval population. Maize plant age had a clear effect on the damage percentage caused by the larvae in the field during the two years of the study. The dramatic spread of FAW and the consequent damage (that appeared in different countries of America, Africa, and Asia) mean that different management approaches must be sought for the small and large-scale producers by using available technologies for smallholder farmers will eliminate pest damage without access to reach to an economic Injury level. This information may assist the decision maker when planning the S. frugiperda IPM program for maize plants and its surveillance.

A lagarta-do-cartucho [FAW; Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)], é considerada uma séria praga invasora que representa uma séria ameaça à segurança alimentar mundial. Essa espécie pode devastar completamente as plantações de cereais de um país inteiro. Portanto, o presente trabalho é o primeiro ensaio de campo no Egito para elucidar alguns aspectos ecológicos de S. frugiperda em plantas de milho (Single-Hybrid 168 Yellow Corn cultivar) no distrito de Esna, Luxor Governorate, Egito, ao longo de duas estações de crescimento sequencial de milho (2021 a 2022). Três parâmetros de insetos foram utilizados, isto é, massas de ovos, número de larvas e porcentagem de plantas de milho danificadas. Também foram estimados os efeitos de certas condições climáticas e idades das plantas de milho na atividade sazonal de S. frugiperda e na porcentagem de plantas danificadas. A população de S. frugiperda começou a atacar as plantas de milho a partir da terceira semana de junho até a colheita em todas as estações. S. frugiperda apresentou dois picos sazonais de atividade como o número de massas de ovos e três picos em relação à densidade populacional larval/estação. Seu percentual de dano aumentou semanalmente a partir do aumento da idade da planta. A média das massas de ovos de S. frugiperda foi de 2,83 ± 0,40 e 2,96 ± 0,45 massa/10 plantas de milho em 2021 e 2022, respectivamente. Enquanto, as populações larvais médias gerais foram de 13,41 ± 0,52 e 13,03 ± 0,46 larvas/10 plantas, durante as duas estações de crescimento, respectivamente. As porcentagens de danos às plantas de milho atingiram 68,54 ± 2,71 e 60,42 ± 2,92% em 2021 e 2022, respectivamente. Os efeitos combinados das condições climáticas e da idade das plantas de milho foram altamente significativos nas massas de ovos, densidade populacional de larvas e porcentagem de danos, e variaram de uma estação para outra. A temperatura média diária máxima foi a variável mais efetiva sobre as massas de ovos e a população larval. A idade da planta de milho influenciou visivelmente o percentual de dano causado pelas larvas no campo durante os dois anos de estudo. A propagação dramática da LFM e os danos consequentes (que apareceram em diferentes países da América, África e Ásia) significam que devem ser utilizadas diferentes abordagens de gestão para os pequenos e grandes produtores, a partir de tecnologias disponíveis para os pequenos agricultores eliminarem os danos causados pelas pragas sem acesso para chegar a um nível de dano econômico. Essas informações podem auxiliar o tomador de decisão no planejamento do programa MIP de S. frugiperda para plantas de milho e o seu monitoramento.

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As poedeiras criadas em sistema degaiolas tem seu bem-estar afetado devido ao menor espaço disponível para elas, o que vai de encontro da crescente pressão por grande parte de consumidores preocupados com as condições em que essas aves são criadas. A consequência dessa menor densidade de alojamento sobre a produtividade, e a qualidade de vida da ave e dos ovos por elas produzidos deve ser avaliada. O objetivo desse estudo é avaliar a produção, qualidade de ovos, e bem-estar de galinhas poedeiras criadas em diferentes densidades de alojamentos em gaiolas. Às 28 semanas de idade, foram distribuídas, em delineamento inteiramente casualizado, 120 poedeiras leves da linhagem Novogen White, após debicagem, em 24 gaiolas com dimensões de 45 cm x 50cm, em três diferentes densidades de alojamento: 562,5 cm² /ave (quatro aves/gaiola), 450 cm² /ave (cinco aves/gaiola) e 375 cm² /ave(seis aves/gaiola), com 8 repetições cada. As dietas experimentais foram isoproteicas e isoenergéticas, formuladas à base de milho e farelo de soja. O período experimental será compreendido por seis ciclos de 28 dias cada. As variáveis analisadas foram: peso do ovo, índice de gema, unidade Haugh, pigmentação da gema, porcentagem dos componentes dos ovos e espessura de casca (em milímetros). Quando as aves atingiram 44 semanas de idade, foi realizada a medição do escore de penas. Foram avaliadas 40 galinhaspor tratamento, em quatro regiões: peito, dorso, asas e posterior. Essa análise consiste emcategorizar as aves de acordo com três diferentes escores, de acordo com o tamanho da área de ausência de penas em cada região. Espera-se que a redução da densidade de alojamento das galinhas nas gaiolas propicie maior produção com melhor qualidade dos ovos, promovendo também melhor bem-estar das aves.(AU)

The well-beingof laying hens raised in cages is affected due to the smaller space available for them,which is in line with the growing pressure from a large number of consumers concerned about the conditions in which these birds are raised.The consequence of thislower housing density on productivity and the quality of life of the bird andthe eggs produced by them must be evaluated. The aim of this study is to evaluate the production, egg quality, and welfare of laying hens reared in different housing densities in cages. At 28 weeks of age, 120 light Novogen White laying hens were distributed, after beak trimming, in24 cages measuring 45 cm x 50 cm, in three different housing densities: 562.5 cm²/bird (four birds/cage), 450 cm²/bird (five birds/cage) and 375 cm²/bird (six birds/cage), with 8 repetitions each. The experimental diets were isoproteic and isoenergetic, based on corn and soybean meal. The trial period will comprise six cycles of 28 days each. The variables analyzed were: egg weight, yolk index, Haugh unit, yolk pigmentation, percentage of egg components and shell thickness (in millimeters). When the birds reached 44 weeks of age, the feather score was measured. Forty chickens per treatment were evaluated in four regions: chest, back, wings and hindquarters. This analysis consists of categorizing the birds according to three different scores, according to thesize of the area without feathers in each region. It is expected that the reduction in the hen housing density in the cages will lead to higher production with better egg quality, also promoting better hen welfare.(AU)

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We aimed to assess how biofilm formation by three Bacillus isolates was affected by changes in temperature, water potential, growth media, time, and the combinations between these factors. The strains had been selected as potential biological control agents (BCAs) in earlier studies, and they were identified as B. subtilis and B. velezensis spp. through 16 rRNA sequencing and MALDI-TOF MS. Maize leaves (ML) were used as one of the growth media, since they made it possible to simulate the nutrient content in the maize phyllosphere, from which the bacteria were originally isolated. The strains were able to form biofilm both in ML and biofilm-inducing MSgg after 24, 48, and 72 h. Biofilm development in the form of pellicles and architecturally complex colonies varied morphologically from one strain to another and depended on the conditions mentioned above. In all cases, colonies and pellicles were less complex when both temperature and water potential were lower. Scanning electron microscopy (SEM) revealed that changing levels of complexity in pellicles were correlated with those in colonies. Statistical analyses found that the quantification of biofilm produced by the isolates was influenced by all the conditions tested. In terms of motility (which may contribute to biofilm formation), swimming and swarming were possible for all strains in 0.3 and 0.7% agar, respectively. A more in-depth understanding of how abiotic factors influence biofilm formation can contribute to a more effective use of these biocontrol strains against pathogens in the maize phyllosphere.

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The consumption of food with a high content of bioactive compounds is correlated with the prevention of chronic degenerative diseases. Tomato is a food with exceptional nutraceutical value; however, saline stress severely affects the yield, the quality of fruits, and the agricultural productivity of this crop. Recent studies have shown that seed priming can mitigate or alleviate the negative effects caused by this type of stress. However, the use of carbon nanomaterials (CNMs) in this technique has not been tested for this purpose. In the present study, the effects of tomato seed priming with carbon nanotubes (CNTs) and graphene (GP) (50, 250, and 500 mg L-1) and two controls (not sonicated and sonicated) were evaluated based on the content of photosynthetic pigments in the leaves; the physicochemical parameters of the fruits; and the presence of enzymatic and non-enzymatic antioxidant compounds, carotenoids, and stress biomarkers such as hydrogen peroxide (H2O2) and malondialdehyde (MDA) in the leaves and fruits of tomato plants without saline stress and with saline stress (50 mM NaCl). The results show that saline stress in combination with CNTs and GP increased the content of chlorophylls (9.1-21.7%), ascorbic acid (19.5%), glutathione (≈13%), proteins (9.9-11.9%), and phenols (14.2%) on the leaves. The addition of CNTs and GP increased the activity of enzymes (CAT, APX, GPX, and PAL). Likewise, there was also a slight increase in the content of H2O2 (by 20.5%) and MDA (3.7%) in the leaves. Salinity affected the quality of tomato fruits. The physico-chemical parameters and bioactive compounds in both the stressed and non-stressed tomato plants were modified with the addition of CNTs and GP. Higher contents of total soluble solids (25.9%), phenols (up to 144.85%), flavonoids (up to 37.63%), ascorbic acid (≈28%), and lycopene (12.4-36.2%) were observed. The addition of carbon nanomaterials by seed priming in tomato plants subjected to saline stress modifies the content of bioactive compounds in tomato fruits and improves the antioxidant defense system, suggesting possible protection of the plant from the negative impacts of stress by salinity. However, analysis of the mechanism of action of CNMs through seed priming, in greater depth is suggested, perhaps with the use of omics sciences.

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The success rate for the evaluation of the results of techniques of Assisted Human Reproduction implies the occurrence of pregnancy with a live, healthy child. There are reports of the association between chemical and unhealthy environmental air conditions (bacteria, dust, particulates and volatile compounds) and reducing the success rate of embryo production and the occurrence of pregnancy. This paper reviews available information about the interference of biochemical, environmental and microbiological changes with the success of the assisted reproductive technique.

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BACKGROUND: Leptospirosis is among the leading zoonotic causes of morbidity and mortality worldwide. Knowledge about spatial patterns of diseases and their underlying processes have the potential to guide intervention efforts. However, leptospirosis is often an underreported and misdiagnosed disease and consequently, spatial patterns of the disease remain unclear. In the absence of accurate epidemiological data in the urban agglomeration of Santa Fe, we used a knowledge-based index and cluster analysis to identify spatial patterns of environmental and socioeconomic suitability for the disease and potential underlying processes that shape them. METHODS: We geocoded human leptospirosis cases derived from the Argentinian surveillance system during the period 2010 to 2019. Environmental and socioeconomic databases were obtained from satellite images and publicly available platforms on the web. Two sets of human leptospirosis determinants were considered according to the level of their support by the literature and expert knowledge. We used the Zonation algorithm to build a knowledge-based index and a clustering approach to identify distinct potential sets of determinants. Spatial similarity and correlations between index, clusters, and incidence rates were evaluated. RESULTS: We were able to geocode 56.36% of the human leptospirosis cases reported in the national epidemiological database. The knowledge-based index showed the suitability for human leptospirosis in the UA Santa Fe increased from downtown areas of the largest cities towards peri-urban and suburban areas. Cluster analysis revealed downtown areas were characterized by higher levels of socioeconomic conditions. Peri-urban and suburban areas encompassed two clusters which differed in terms of environmental determinants. The highest incidence rates overlapped areas with the highest suitability scores, the strength of association was low though (CSc r = 0.21, P < 0.001 and ESc r = 0.19, P < 0.001). CONCLUSIONS: We present a method to analyze the environmental and socioeconomic suitability for human leptospirosis based on literature and expert knowledge. The methodology can be thought as an evolutive and perfectible scheme as more studies are performed in the area and novel information regarding determinants of the disease become available. Our approach can be a valuable tool for decision-makers since it can serve as a baseline to plan intervention measures.

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The objective was to evaluate the effect of the season on the sexual behavior patterns adopted by Morada Nova sheep in the Brazilian semiarid region. A total of 55 and 59 female sheep were used in the rainy and dry seasons, respectively, attended by four males of the same breed in rotation. The females identified in oestrus were released in a pasture, together with the breeder of the day for each season, and aspects of sexual behavior were measured for an uninterrupted period of 11 hours/day. Assuming a negative binomial distribution, the behavioral frequencies were subjected to deviation analysis and compared using the chi-square. Heading in the male was observed more frequently during the rainy season (0.12) and shifts with higher temperatures; the turn of the head in relation to the man was observed more frequently during the dry season (2.49). The interactions between seasons and shifts significantly affected the following behaviors: sniffing the male, sniffing the male's urogenital region, wagging the tail, lifting the tail, and urinating. Behavioral variables were influenced by the season. Morada Nova sheep reduce their water intake and grazing time to engage more efficiently in reproductive activities, thus demonstrating an ability to adapt to the Caatinga.

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he objective was to evaluate the effect of the season on the sexual behavior patterns adopted by Morada Nova sheep in the Brazilian semiarid region. A total of 55 and 59 female sheep were used in the rainy and dry seasons, respectively, attended by four males of the same breed in rotation. The females identified in oestrus were released in a pasture, together with the breeder of the day for each season, and aspects of sexual behavior were measured for an uninterrupted period of 11 hours/day. Assuming a negative binomial distribution, the behavioral frequencies were subjected to deviation analysis and compared using the chi-square. Heading in the male was observed more frequently during the rainy season (0.12) and shifts with higher temperatures; the turn of the head in relation to the man was observed more frequently during the dry season (2.49). The interactions between seasons and shifts significantly affected the following behaviors: sniffing the male, sniffing the male's urogenital region, wagging the tail, lifting the tail, and urinating. Behavioral variables were influenced by the season. Morada Nova sheep reduce their water intake and grazing time to engage more efficiently in reproductive activities, thus demonstrating an ability to adapt to the Caatinga.(AU)

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An increase in 2,4-D use is expected as tolerant crops have been approved to use in Brazil, which may negatively affect important crops such as tobacco. Our objective was to determine safe distances between 2,4-D applications and tobacco fields considering herbicide contamination to the harvested product. A field experiment was conducted, consisting of a 2,4-D application done perpendicularly to the wind direction, using a tractor sprayer. Drifted herbicide was collected using tobacco plants placed at various points (-50 up to 400 meters from application zone), following three schemes: a) 0 to 0.5 hours after application (HAT); b) 0 to 24 HAT; and c) 0.5 to 24 HAT. Environmental conditions were recorded. Herbicide in tobacco leaves was quantified. Drift was detected up to 200 m in both years. Vapor movement of 2,4-D was detected up to 400 m from the application strip in 2016, on plants taken to the field after herbicide application. Environmental conditions in 2015 favored off-target movement (higher wind speed and air temperature and lower humidity); although, in 2016 the herbicide traveled further due to wet deposition. These results indicated that a 100-meter buffer zone is enough to significantly decrease chances of tobacco contamination above the tolerated threshold, and highlighted the importance of environmental conditions in the transport processes for 2,4-D under field conditions.

O aumento no uso do 2,4-D é esperado, uma vez que as culturas tolerantes foram aprovadas para uso no Brasil, o que pode afetar negativamente culturas importantes, como o tabaco. Nosso objetivo foi determinar a distância segura entre aplicações de 2,4-D e lavouras de tabaco, considerando a contaminação do herbicida no produto colhido. Um experimento de campo foi realizado, utilizando aplicação de 2,4-D perpendicularmente à direção do vento, com pulverizador tratorizado. A deriva do herbicida foi coletada plantas de tabaco colocadas em vários pontos (-50 até 400 metros da zona de aplicação), seguindo três esquemas: a) 0 a 0,5 horas após a aplicação (HAT); b) 0 a 24 HAT; e c) 0,5 a 24 HAT. As condições ambientais foram registradas. Foi quantificado o herbicida em folhas de tabaco. A deriva foi detectada até 200 m em 2015 e até 150 m em 2016. A volatilização ocorreu em ambos os anos, pois o 2,4-D foi detectado em plantas transportadas para o campo após a aplicação. As condições ambientais em 2015 favoreceram o movimento fora do alvo (maior velocidade do vento e temperatura do ar e menor umidade). Esses resultados indicam que uma zona de exclusão de 100 metros é suficiente para diminuir significativamente as chances de contaminação do tabaco acima do limite tolerado e, destaca a importância das condições ambientais nos processos de transporte do 2,4-D em condições de campo.

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Real-time PCR is widely used to study the relative abundance of mRNA due to its specificity, sensitivity, and repeatability quantification. However, relative quantification requires a reference gene, which should be stable in its expression, showing lower variation by experimental conditions or tissues. The aim of this study was to evaluate the stability of the expression of five commonly used reference genes (actb, ywhaz, b2m, sdha, and 18s rRNA) at different physiological stages (alert and emergency) in three different cattle breeds. In this study, five genes (actb, ywhaz, b2m, sdha, and 18s rRNA) were selected as candidate reference genes for expression studies in the whole blood from three cattle breeds (Romosinuano, Gyr, and Brahman) under heat stress conditions. The transcription stability of the candidate reference genes was evaluated using geNorm and NormFinder. The results showed that actb, 18SrRNA, and b2m expression were the most stable reference genes for whole blood of Gyr and Brahman breeds under two states of livestock weather safety (alert and emergency). Meanwhile, actb, b2m, and ywhaz were the most stable reference genes for the Romosinuano breed.

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Fires can pose a threat to forest ecosystems when those ecosystems are not fire-adapted or when forest community conditions make them vulnerable to wildfires. Thus, investigating fire-prone environmental conditions is urgently needed to create action plans that preserve these ecosystems. In this sense, climate variables can determine the environmental conditions favorable for forest fires. Our study confirms that vapor pressure deficit (VPD) is an essential climate indicator for forest fires, as it is related to maximum temperatures and low humidity, representing the stress conditions for vegetation prone to fires. This study explores the extent to which ENSO phases can modulate climatic conditions that lead to high VPD over Guanajuato, a semi-arid region in central Mexico, during the dry season (March-April-May). Using fire occurrence data from MODIS (2000-2019) and Landsat 5 (1998-1999), we developed a climatic probability model for the occurrence of forest fires using VPD estimated from ERA5 reanalysis for each ENSO phase. We found that VPD and the occurrence of forest fires were higher during El Niño than under Neutral and La Niña years, with a higher risk of forest fire occurrence in Guanajuato's southern region. This study concludes that it is necessary to implement regional and local fire management plans, especially where the largest number of natural protected areas is located.

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This paper explores the main factors for mosquito-borne transmission of the Zika virus by focusing on environmental, anthropogenic, and social risks. A literature review was conducted bringing together related information from this genre of research from peer-reviewed publications. It was observed that environmental conditions, especially precipitation, humidity, and temperature, played a role in the transmission. Furthermore, anthropogenic factors including sanitation, urbanization, and environmental pollution promote the transmission by affecting the mosquito density. In addition, socioeconomic factors such as poverty as well as social inequality and low-quality housing have also an impact since these are social factors that limit access to certain facilities or infrastructure which, in turn, promote transmission when absent (e.g., piped water and screened windows). Finally, the paper presents short-, mid-, and long-term preventative solutions together with future perspectives. This is the first review exploring the effects of anthropogenic aspects on Zika transmission with a special emphasis in Brazil.

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The influence of short-term (daily) variation in environmental conditions (rainfall, wind, tide, river flow) on debris accumulation was examined on two beaches at an estuarine outlet. Sampling occurred over 60 consecutive days along two sections (Internal Area, IA; and External Area, EA) of the Paranaguá Estuary Complex's southern outlet, in Paraná, southern Brazil. The IA is sheltered from direct wave action, whereas the EA is more exposed to wave and wind action from the open ocean. The IA accounted for 71% of the total debris, while the EA accounted for 29%. Debris abundance was highest after intermediate bouts of rainfall, although river flow only affected debris accumulation in the IA. Wind and tide influenced accumulation differently across sites. These results highlight the importance of short-term variation in the accumulation of marine debris on sandy beaches, which should be considered when designing and monitoring assessment programs and removal strategies.

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Ocotea quixos (Lam.) Kosterm. is an aromatic tree native to Ecuador, whose leaves are used to prepare aromatic beverages to which different health benefits are attributed. In this study, Ocotea quixos leaves were collected in the Amazon region in different environmental conditions and subjected to hydrodistillation to isolate the essential oil. The collection variables used were type of soil, amount of shade, and height; in addition, the presence of twig and leaf age and moisture were used as variables. Chemical composition was analyzed by means of gas chromatography equipped with a flame ionization detector and gas chromatography coupled to mass spectrometry. A wide variety of chemical compositions were detected in the samples. In total, forty-seven compounds were identified, which represented between 97.17% and 99.89% of the total composition. The constituents were mainly grouped into aliphatic sesquiterpene hydrocarbons (33.03-55.89%), other compounds (8.94-47.83%), and oxygenated monoterpenes (1.97-39.66%). The main constituents were found to be (E)-cinnamyl acetate (5.96-41.65%), (E)-methyl cinnamate (0.38-37.91%), and trans-caryophyllene (8.77-37.02%). The statistical analysis suggested the existence of two essential oil chemotypes and a direct correlation between environmental conditions and chemical composition of the essential oils.

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Billions of people are at risk due to mosquito-borne diseases. Ideally, the control of mosquito-borne diseases should integrate mosquito control and surveillance to maximize transmission prevention while minimizing environmental impacts. Mosquito surveillance is often limited in scope by logistical constraints, especially the labour and expertise in identifying captured mosquitoes. Mosquito sounds, primarily the wingbeat frequencies (WBF), have been extensively studied in the literature, often targeting a straightforward assessment of this technology with species identification in laboratory conditions. Optical sensors for measuring the WBF of free-flying mosquitoes are the most recent proposal to automate species identification. However, many of the factors that may influence WBF within and between species have not been fully examined, resulting in failures in the species identification. Here we show that body size and temperature modify the wingbeat frequency of female Aedes [Stegomyia] aegypti Linnaeus (Diptera:Culicidae) and such an optical sensor can capture these alterations. We demonstrate that this study's optical sensor can distinguish wingbeat frequency from large and small mosquitoes at different temperatures. The relationship between WBF and size should be taken into account to improve the accuracy of devices that automatically identify species using WBF.

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