RESUMO
Dengue is a vector-borne disease that has increased over the past two decades, becoming a global public health emergency. The transmission of dengue is contingent upon various factors, among which climate variability plays a significant role. However, there remains substantial uncertainty regarding the underlying mechanisms. This study aims to investigate the spatial and temporal patterns of dengue risk and to quantify the associated risk factors in Valle del Cauca, Colombia, from 2001 to 2019. To achieve this, a spatio-temporal Bayesian hierarchical model was developed, integrating delayed and non-linear effects of climate variables, socio-economic factors, along with spatio-temporal random effects to account for unexplained variability. The results indicate that average temperature is positively associated with dengue risk 0-2 months later, showing a 35% increase in the risk. Similarly, high precipitation levels lead to increased risk approximately 2-3 months later, while relative humidity showed a constant risk within a 6 months-lag. These findings could be valuable for local health authorities interested in developing early warning systems to predict future risks in advance.
Assuntos
Teorema de Bayes , Dengue , Colômbia/epidemiologia , Dengue/epidemiologia , Dengue/transmissão , Humanos , Mudança Climática , Análise Espaço-Temporal , Clima , Temperatura , Fatores de Risco , UmidadeRESUMO
Heat stress has been recognized as a serious problem in dairy farms around the world due to the increasing heat waves and higher genetic potential of dairy cows. In Chile, milk production is concentrated in the southern regions of the country, where animals graze all year around, consequently being exposed directly to environmental conditions. Nevertheless, there are few studies conducted in Chile that have evaluated at the commercial level the impact of heat stress on milk production. The aim of this study was to assess the effects of summer conditions, across periods, on the milk production of cows at different stages of lactation in a dairy farm located in Southern Chile. Daily meteorological and milk yield records of three summers from a dairy farm were collected to characterize the relationship between two thermal stress indices and milk yield. The thermal comfort indices used were the comprehensive climate index (CCI), and the adjusted temperature humidity index (THIadj). The average values of CCI and THIadj were dependent on the period (P < 0.0001) with maximum CCI of 40.2 °C, 31.7 °C, and 27.5 °C for the 2012-2013, 2015-2016, and 2016-2017 periods, respectively. A similar response was recorded when THIadj was used (85.5, 78.0, and 73.9, respectively). In the 2012-2013 summer, 44.4% of the days presented conditions of heat stress (CCI ≥23), a value that fell to 26.7% in the summer of 2015-2016 and only 5.6% in the 2016-2017. On the opposite, when the THIadj was used, these values were 50%, 48.9%, and 5.6%, respectively. In conclusion, both comfort thermal indices are good tools to determine the risk of thermal stress in dairy cows, with a large variation between the three summer periods but also between indices. Likewise, cows in the early and mid-lactation periods are more affected in terms of milk yield.
Assuntos
Resposta ao Choque Térmico , Lactação , Animais , Bovinos/fisiologia , Feminino , Chile , Indústria de Laticínios , Umidade , Leite/metabolismo , Estações do Ano , Transtornos de Estresse por Calor/veterinária , Transtornos de Estresse por Calor/fisiopatologia , Temperatura Alta/efeitos adversosRESUMO
BACKGROUND: Exposure to extreme heat impacts millions of people worldwide and outdoor workers are among the populations most affected by hot temperatures. Heat stress induces several biological responses in humans, including the production of heat shock proteins (HSP) and antibodies against HSP (anti-HSP) which may play a central role in the body's cellular response to a hot environment. OBJECTIVE: This longitudinal study investigated the impact of elevated temperatures and humidity on the presence of HSP70 and anti-HSP70 and examined relationships with markers of kidney function in an at-risk workforce under conditions of extreme heat and exertion in Guatemala. METHODS: We collected ambient temperature and relative humidity data as well as biomarkers and clinical data from 40 sugarcane workers at the start and the end of a 6-month harvest. We used generalized mixed-effects models to estimate temperature effects on HSP70 and anti-HSP70 levels. In addition, we examined trends between HSP70 and anti-HSP70 levels and markers of kidney function across the harvest. RESULTS: At the end of the harvest, temperatures were higher, and workers had, on average, higher levels of HSP70 and anti-HSP70 compared to the beginning of the season. We observed significant increasing trends with temperature indices, heat index, and HSP70 levels. Maximum temperature was associated with HSP70 increments after controlling for age, systolic and diastolic blood pressure (ß: 0.21, 95% Confidence Interval: 0.09, 0.33). Kidney function decline across the harvest was associated with both higher levels of anti-HSP70 levels at the end of the harvest as well as greater increases in anti-HSP70 levels across the harvest. CONCLUSIONS: These results suggest that workplace heat exposure may increase the production of HSP70 and anti-HSP70 levels and that there may be a relationship between increasing anti-HSP70 antibodies and the development of renal injury. HSP70 holds promise as a biomarker of heat stress in exposed populations.
Assuntos
Biomarcadores , Fazendeiros , Proteínas de Choque Térmico HSP70 , Temperatura Alta , Exposição Ocupacional , Humanos , Proteínas de Choque Térmico HSP70/imunologia , Proteínas de Choque Térmico HSP70/sangue , Estudos Longitudinais , Masculino , Biomarcadores/sangue , Adulto , Feminino , Exposição Ocupacional/efeitos adversos , Temperatura Alta/efeitos adversos , Pessoa de Meia-Idade , Guatemala , Rim , Agricultura , Anticorpos/sangue , Transtornos de Estresse por Calor , UmidadeRESUMO
Temperature and humidity are studied in the context of seasonal infections in temperate and tropical zones, but the relationship between viral trends and climate variables in temperate subtropical zones remains underexplored. Our retrospective study analyzes respiratory pathogen incidence and its correlation with climate data in a subtropical zone. Retrospective observational study at Moinhos de Vento Hospital, South Brazil, aiming to assess seasonal trends in respiratory pathogens, correlating them with climate data. The study included patients of all ages from various healthcare settings, with data collected between April 2022 and July 2023. Biological samples were analyzed for 24 pathogens using polymerase chain reaction and hybridization techniques; demographic variables were also collected. The data was analyzed descriptively and graphically. Spearman tests and Poisson regression were used as correlation tests. Tests were clustered according to all pathogens, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza viruses, rhinovirus, and respiratory syncytial virus (RSV). Between April 2022 and July 2023, 3329 tests showed a 71.6% positivity rate. Rhinovirus and RSV predominated, exhibiting seasonal patterns. Temperature was inversely correlated with the viruses, notably rhinovirus, but SARS-CoV-2 was positively correlated. Air humidity was positively correlated with all pathogens, RSV, rhinovirus, and atmospheric pressure with all pathogens and rhinovirus. Our results showed statistically significant correlations, with modest effect sizes. Our study did not evaluate causation effects. Despite the correlation between climate and respiratory pathogens, our work suggests additional factors influencing transmission dynamics. Our findings underscore the complex interplay between climate and respiratory infections in subtropical climates.
Assuntos
COVID-19 , Umidade , Estações do Ano , Temperatura , Humanos , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/transmissão , COVID-19/virologia , Brasil/epidemiologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Criança , Adolescente , Pré-Escolar , Idoso , Adulto Jovem , Lactente , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Clima , Infecções Respiratórias/virologia , Infecções Respiratórias/epidemiologia , Clima Tropical , Recém-Nascido , Rhinovirus/genética , Rhinovirus/isolamento & purificação , Incidência , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/virologia , Idoso de 80 Anos ou maisRESUMO
Many habitat-specialist organisms occur in distinct, patchy habitat, yet do not occupy all patches, and an important question is why apparently suitable habitat remains unoccupied. We examined factors influencing patch occupancy in near-threatened, little-known Diademed Plovers (Phegornis mitchellii), arguably the bird most specialized to life in High Andean peatlands. Andean peatlands are well-suited to occupancy modelling because they are discrete patches of humid habitat within a matrix of high-altitude steppe. We hypothesized that Diademed Plovers occupy preferably larger and more humid peatlands, and avoid peatlands used for grazing by llamas and vicuñas, which may trample vegetation and nests. From December 2021 to February 2022 (breeding season), we conducted plover occupancy surveys (2-4) on 40 peatlands at Lagunas de Vilama, a landscape of arid steppe and wetlands above 4,500 m in NW Argentina. We measured peatland size, grazing pressure, topographic and remotely-sensed variables that correlate with humidity, and incorporated these as covariates in occupancy models. Occupancy models showed that more than 50% of the studied peatlands were used by Diademed Plovers and most showed signs of reproduction, highlighting the importance of the Vilama Wetlands for Diademed Plover conservation. Within peatlands, Diademed Plovers were most often associated with headwaters. The top ranked occupancy model included constant detection, random spatial effects, and a single occupancy covariate: mean NDWI (Normalized Difference Water Index, an index correlated with water content and humidity) over the previous three years. Contrary to our prediction, Diademed Plovers preferred less water-saturated peatlands (lower NDWI), possibly to avoid nest flooding. This may be especially important in wet years, like the year when we conducted our surveys. Neither peatland size nor grazing by llamas and vicuñas affected peatland use by Diademed Plovers, suggesting that llama grazing at current levels may be compatible with plover conservation. For organisms that specialize on humid habitats, such as peatlands, factors affecting occupancy may vary temporally with variation in climate, and we recommend follow-up surveys across multi-year timescales to untangle the impact of climate on animals' use of humid habitats.
Assuntos
Camelídeos Americanos , Ecossistema , Umidade , Animais , Camelídeos Americanos/fisiologia , Argentina , Áreas Alagadas , Herbivoria , Espécies em Perigo de Extinção , Solo/químicaRESUMO
The objectives of this study were to assess the adequacy of physical parameters/factors (temperature, relative humidity, noise, and illuminance levels) of the work environment in PHC facilities, to evaluate the association between the adequacy of these measured physical parameters and the physical characteristics of the PHC facilities and their surroundings and to assess the association between health professionals' perceptions about exposure to physical risks in the PHC work environment and the adequacy of physical parameters measured in the same facilities. The study monitored 23 PHC facilities in southern Brazil and interviewed 210 health professionals. Data analysis involved Pearson's chi-square, Fisher's exact test, Spearman's correlation, and multivariate linear regression analysis was used to control for confounding factors. The significance level was set at 5% (p ≤ 0.05). The combination of temperature and relative humidity presented thermal comfort levels outside the adopted criteria for adequacy in consultation (outdoor relative humidity, p = 0.013) and procedure rooms (front door open, p = 0.034). Inadequate sound comfort (noise) levels in the morning shift were found in the vaccination (front door open, p = 0.021) and consultation rooms (movement of people, p = 0.016). In PHC facilities where reception rooms had insufficient lighting, internal curtains were opened less frequently (p = 0.047). The analysis of health professionals' perceptions of physical factors demonstrated that physicians more frequently perceive the physical risk of temperature and humidity (p = 0.044). The higher the number of nurses (p = 0.004) and oral health technicians in the PHC facilities (p = 0.031), the greater the general percentage of adequacy of monitored physical parameters. It was also confirmed that the higher the perception of moderate or severe physical risk among health professionals, the lower the general percentage of the adequacy of the physical parameters of the work environment of the PHC facilities evaluated (rs = -0.450, p = 0.031). This study's evidence contributes to a better understanding of physical conditions and future occupational interventions to ensure the comfort, safety, and well-being of PHC workers.
Assuntos
Atenção Primária à Saúde , Local de Trabalho , Humanos , Brasil , Feminino , Masculino , Adulto , Local de Trabalho/psicologia , Pessoal de Saúde/psicologia , Pessoa de Meia-Idade , Umidade , Instituições de Assistência Ambulatorial , Temperatura , Exposição Ocupacional , Iluminação , Atitude do Pessoal de Saúde , Percepção , Condições de TrabalhoRESUMO
BACKGROUND: Sucrose accumulation in sugarcane is affected by several environmental and genetic factors, with plant moisture being of critical importance for its role in the synthesis and transport of sugars within the cane stalks, affecting the sucrose concentration. In general, rainfall and high soil humidity during the ripening stage promote plant growth, increasing the fresh weight and decreasing the sucrose yield in the humid region of Colombia. Therefore, this study aimed to identify markers associated with sucrose accumulation or production in the humid environment of Colombia through a genome-wide association study (GWAS). RESULTS: Sucrose concentration measurements were taken in 220 genotypes from the Cenicaña's diverse panel at 10 (early maturity) and 13 (normal maturity) months after planting. For early maturity data was collected during plant cane and first ratoon, while at normal maturity it was during plant cane, first, and second ratoon. A total of 137,890 SNPs were selected after sequencing the 220 genotypes through GBS, RADSeq, and whole-genome sequencing. After GWAS analysis, a total of 77 markers were significantly associated with sucrose concentration at both ages, but only 39 were close to candidate genes previously reported for sucrose accumulation and/or production. Among the candidate genes, 18 were highlighted because they were involved in sucrose hydrolysis (SUS6, CIN3, CINV1, CINV2), sugar transport (i.e., MST1, MST2, PLT5, SUT4, ERD6 like), phosphorylation processes (TPS genes), glycolysis (PFP-ALPHA, HXK3, PHI1), and transcription factors (ERF12, ERF112). Similarly, 64 genes were associated with glycosyltransferases, glycosidases, and hormones. CONCLUSIONS: These results provide new insights into the molecular mechanisms involved in sucrose accumulation in sugarcane and contribute with important genomic resources for future research in the humid environments of Colombia. Similarly, the markers identified will be validated for their potential application within Cenicaña's breeding program to assist the development of breeding populations.
Assuntos
Estudo de Associação Genômica Ampla , Umidade , Saccharum , Sacarose , Saccharum/genética , Saccharum/metabolismo , Colômbia , Sacarose/metabolismo , Polimorfismo de Nucleotídeo Único , GenótipoRESUMO
Although food is produced in aquaponics systems worldwide, no information is available on the occurrence of insect pests and natural enemies in aquaponic lettuce, Lactuca sativa L. In this study, a survey was carried out in an aquaponic system combining lettuce with lambari, Astyanax altiparanae (Garutti & Briski), aiming to determine the insect pests and natural enemies associated with this system. We also determined the predominant insect species and the effect of meteorological factors on their populations. Insect abundance was estimated by visual sampling during 13 cultivation cycles, totaling 27 sampling dates. The meteorological factors considered were air temperature and relative humidity, and their effects were determined using the Pearson correlation. The thrips Frankliniella schultzei (Trybom) and Caliothrips phaseoli (Hood) and the aphid Aphis spiraecola (Patch) predominated. Ambient temperature and relative humidity were essential factors affecting C. phaseoli and F. schultzei. The natural enemies found on the lettuce plants were the thrips Franklinothrips vespiformis (Crawford) and Stomatothrips angustipennis (Hood) and the ladybugs Cycloneda sanguinea L., Eriopis connexa (Germar), and Hippodamia convergens (Guérin-Méneville). These results constitute the first step for a lettuce-integrated pest-management program in aquaponics systems.
Assuntos
Lactuca , Animais , Lactuca/parasitologia , Lactuca/crescimento & desenvolvimento , Afídeos/fisiologia , Insetos/fisiologia , Umidade , Temperatura , Tisanópteros/fisiologia , Controle Biológico de Vetores/métodosRESUMO
BACKGROUND: Arthropods vector a multitude of human disease-causing organisms, and their geographic ranges are shifting rapidly in response to changing climatic conditions. This is, in turn, altering the landscape of disease risk for human populations that are brought into novel contact with the vectors and the diseases they carry. Sand flies in the genera Lutzomyia and Pintomyia are vectors of serious disease-causing agents such as Leishmania (the etiological agent of leishmaniasis) and may be expanding their range in the face of climate change. Understanding the climatic conditions that vector species both tolerate physiologically and prefer behaviorally is critical to predicting the direction and magnitude of range expansions and the resulting impacts on human health. Temperature and humidity are key factors that determine the geographic extent of many arthropods, including vector species. METHODS: We characterized the habitat of two species of sand flies, Lutzomyia longipalpis and Pintomyia evansi. Additionally, we studied two behavioral factors of thermal fitness-thermal and humidity preference in two species of sand flies alongside a key aspect of physiological tolerance-desiccation resistance. RESULTS: We found that Lu. longipalpis is found at cooler and drier conditions than Pi. evansi. Our results also show significant interspecific differences in both behavioral traits, with Pi. evansi preferring warmer, more humid conditions than Lu. longipalpis. Finally, we found that Lu. longipalpis shows greater tolerance to extreme low humidity, and that this is especially pronounced in males of the species. CONCLUSIONS: Taken together, our results suggest that temperature and humidity conditions are key aspects of the climatic niche of Lutzomyia and Pintomyia sand flies and underscore the value of integrative studies of climatic tolerance and preference in vector biology.
Assuntos
Ecossistema , Umidade , Psychodidae , Temperatura , Animais , Psychodidae/fisiologia , Psychodidae/classificação , Feminino , Masculino , Insetos Vetores/fisiologiaRESUMO
In dengue-endemic areas, transmission control is limited by the difficulty of achieving sufficient coverage and sustainability of interventions. To maximize the effectiveness of interventions, areas with higher transmission could be identified and prioritized. The aim was to identify burden clusters of Dengue virus (DENV) infection and evaluate their association with microclimatic factors in two endemic towns from southern Mexico. Information from a prospective population cohort study (2·5 years of follow-up) was used, microclimatic variables were calculated from satellite information, and a cross-sectional design was conducted to evaluate the relationship between the outcome and microclimatic variables in the five surveys. Spatial clustering was observed in specific geographic areas at different periods. Both, land surface temperature (aPR 0·945; IC95% 0·895-0·996) and soil humidity (aPR 3·018; IC95% 1·013-8·994), were independently associated with DENV burden clusters. These findings can help health authorities design focused dengue surveillance and control activities in dengue endemic areas.
Assuntos
Vírus da Dengue , Dengue , Microclima , Humanos , Dengue/epidemiologia , Dengue/transmissão , México/epidemiologia , Feminino , Masculino , Estudos Transversais , Adulto , Adolescente , Estudos Prospectivos , Criança , Doenças Endêmicas , Adulto Jovem , Pessoa de Meia-Idade , Pré-Escolar , Umidade , Análise por Conglomerados , TemperaturaRESUMO
The study aimed to estimate economic losses associated with heat stress in the eight dairy production regions (DPR), defined by the Dairy Chilean Consortium, using two comfort thermal indices, namely, the temperature-humidity index (THI) and the THI adjusted for solar radiation and wind speed (THIa). Hourly records from 19 weather stations (Nov - Mar 2017-2022) were collected to estimate the comfort thermal indices. The economic impact was estimated considering a critical threshold of 65 for both indices and the effect of higher values on loss in milk yield, days open, culling rate, and deaths. There were differences in the number of hours above the threshold among DPRs, independent of the thermal index used (P < 0.01). The greatest values were observed in DPRs I, II, and VIII, which concentrate most dairy cows. Average losses in milk yield were between 2.0 and 6.4 times higher when THIa was used instead of THI, which also depends on the DPR (P < 0.01). These estimations coincide with those observed empirically by producers. The lowest average economic losses per cow during the summer season (5 seasons average) occurred in DPR VI (US $ 91.5), and the highest losses were observed in DPR I (US $ 184.2) both using THIa. At the country level, economic losses fluctuate between US $ 29.0 and 108.4 million per summer season, depending on the comfort thermal index used. Finally, heat stress impacts negatively and significantly the Chilean dairy sector, which is highly dependent on the DPR.
Assuntos
Indústria de Laticínios , Transtornos de Estresse por Calor , Animais , Chile , Bovinos , Indústria de Laticínios/economia , Feminino , Transtornos de Estresse por Calor/economia , Transtornos de Estresse por Calor/veterinária , Umidade , Leite/economia , Temperatura Alta/efeitos adversos , Doenças dos Bovinos/economia , Doenças dos Bovinos/epidemiologia , Temperatura , Lactação , Estações do AnoRESUMO
Little has been studied about microclimate and the thermal comfort during the implementation of silvopastoral systems. This study aimed to evaluate the microclimate and thermal comfort during the implementation of High Biodiversity Silvopastoral System with Nuclei (SPSnu). Three treatments were investigated, SPSnu with 5 and 10% of the pasture area with nuclei, (SPSnu5 and SPSnu10, respectively), and treeless pasture (TLP). Each treatment was subdivided into 4 areas: within the nuclei, around the nuclei, around the nuclei with shade and internuclei. The analyzed variables were soil surface temperature, air temperature, wind speed, relative humidity, black globe temperature and the Heat Load Index (HLI) at 20 and 120 cm height. We hypothesized that the wind speed reduction associated with insufficient shade projection typical of the first years of SPSs may interfere in microclimate and thermal comfort during the hot seasons. SPSnu5 and SPSnu10 had a reduction in wind speed of 51.58% and 68.47% respectively when compared to TLP at 20 cm. Soil surface temperature and air temperature at 120 cm were higher for SPSnu than TLP. The same effect was observed for the HLI. At 20 cm, HLI indicated better thermal comfort in TLP than in the SPSnu treatments. The lack of shade projection from young nuclei in conjunction with the decrease of wind speed between the nuclei caused a higher air temperature and HLI in the SPSnu treatments, we called this conditions, windbreak countereffect. Farmers must knowledge this effect when implementing SPSs, and when necessary, mitigate with the proper management decisions.
Assuntos
Microclima , Temperatura , Vento , Agricultura/métodos , Umidade , Solo , Sensação Térmica , BiodiversidadeRESUMO
Our aims were to evaluate changes in body characteristics, milk yield and milk constituents as well as to determine the relationship between the thermal environment and production characteristics during the first lactation of dairy Gyr cows managed on pasture. Between 2013 and 2015, forty-five primiparous dairy Gyr cows were evaluated from prepartum to 10 months of lactation in Southeast of Brazil. Body weight, body condition score (BCS), subcutaneous fat thickness (SFT), milk yield (305 d), and milk constituents were collected monthly and progesterone was collected weekly. Additionally, we determined the temperature humidity index (THI) based on microclimate data. Overall, the cows lost body weight until six months of lactation and there was a progressive decrease in BCS, SFT, milk yield and milk lactose as the months in lactation progressed. In contrast, there was an increase in milk fat, milk protein and milk solids. The thermal environment did not pose a consistent heat challenge, nevertheless, we found a positive correlation between the average THI two days before milk collection with milk yield, fat and lactose contents, but in contrast a negative correlation was found with total solids and protein. In conclusion, the THI and months of lactation affected the yield and constituents of milk. However, more studies are necessary to understand the impacts of body characteristics and thermal environment on yield and milk constituents throughout the productive life of Gyr dairy cows.
Assuntos
Umidade , Lactação , Lactose , Leite , Animais , Lactação/fisiologia , Feminino , Bovinos/fisiologia , Leite/química , Lactose/análise , Proteínas do Leite/análise , Temperatura , Peso Corporal , Brasil , Indústria de Laticínios/métodos , Gordura Subcutânea/química , Composição CorporalRESUMO
BACKGROUND: Leptospirosis is an endemic zoonosis in tropical areas that is mainly related to rural activities; nevertheless, human leptospirosis (HL) outbreaks differ among regions. In Colombia, HL notifications are mandatory. Our objective was to determine the spatiotemporal distribution of HL in Colombia during 2007-2018 and its relationship with the main hydroclimatic variables. METHODS: We determined the estimated incidence and lethality of HL according to department and year. The Bayesian spatiotemporal analysis of an autoregressive model (STAR) model included HL cases and hydroclimatic factors (average temperature, rainfall and relative humidity) for quarterly periods. RESULTS: During the study period, 10 586 HL cases were registered (estimated incidence: 1.75 cases x 105) and 243 deaths by HL (lethality 2.3%). The STAR model found association of HL risk with temperature (RR:6.80; 95% CI 3.57 to 12.48) and space. Quindío and three other Amazonian departments (Guainía, Guaviare and Putumayo) had a positive relationship with a significant number of HL cases, adjusted for quarterly precipitation and humidity. CONCLUSION: Spatial analysis showed a high risk of HL in departments of the western Andean Colombian regions. By contrast, in the spatiotemporal model, a higher HL risk was associated with temperature and departments of the North Colombian Amazon regions and Quindío in the Colombian Andean region.
Assuntos
Teorema de Bayes , Leptospirose , Análise Espaço-Temporal , Colômbia/epidemiologia , Humanos , Leptospirose/epidemiologia , Incidência , Fatores de Risco , Temperatura , Clima , Umidade , Chuva , Surtos de DoençasRESUMO
BACKGROUND: Educational environments can have environmental conditions that are incompatible with the needs of students, compromising their well-being and affecting their performance. OBJECTIVE: To identify the environmental variables that influence the performance of university students and measure this influence through an experiment in indoor environments. METHODS: The study applied an experimental methodology for three consecutive days in seven educational environments located in different regions of Brazil, measuring the environ-mental conditions, the students' perception of the environment, and their cognitive performance. The impact of environmental variables and environmental perception on student performance was analyzed using Generalized Linear Models and a Structural Equation Model. RESULTS: Students who took the test at air temperatures between 22.4°C and 24.7°C had a 74.20% chance of performing better than those outside this range. Air temperatures between 26.2°C and 29°C were associated with an 86% chance of taking less time to complete the test. High illuminance levels increased the chance of taking longer to answer the test by 41.7%. CONCLUSIONS: Three environmental variables (relative humidity, lighting and air temperature) and two perceptual dimensions (light and thermal perception) directly influence student performance.
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Cognição , Estudantes , Humanos , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Brasil , Feminino , Masculino , Universidades , Temperatura , Meio Ambiente , Umidade , Iluminação , AdultoRESUMO
Mountain ranges contain high concentrations of endemic species and are indispensable refugia for lowland species that are facing anthropogenic climate change1,2. Forecasting biodiversity redistribution hinges on assessing whether species can track shifting isotherms as the climate warms3,4. However, a global analysis of the velocities of isotherm shifts along elevation gradients is hindered by the scarcity of weather stations in mountainous regions5. Here we address this issue by mapping the lapse rate of temperature (LRT) across mountain regions globally, both by using satellite data (SLRT) and by using the laws of thermodynamics to account for water vapour6 (that is, the moist adiabatic lapse rate (MALRT)). By dividing the rate of surface warming from 1971 to 2020 by either the SLRT or the MALRT, we provide maps of vertical isotherm shift velocities. We identify 17 mountain regions with exceptionally high vertical isotherm shift velocities (greater than 11.67 m per year for the SLRT; greater than 8.25 m per year for the MALRT), predominantly in dry areas but also in wet regions with shallow lapse rates; for example, northern Sumatra, the Brazilian highlands and southern Africa. By linking these velocities to the velocities of species range shifts, we report instances of close tracking in mountains with lower climate velocities. However, many species lag behind, suggesting that range shift dynamics would persist even if we managed to curb climate-change trajectories. Our findings are key for devising global conservation strategies, particularly in the 17 high-velocity mountain regions that we have identified.
Assuntos
Altitude , Migração Animal , Biodiversidade , Mapeamento Geográfico , Aquecimento Global , Animais , África Austral , Brasil , Conservação dos Recursos Naturais , Aquecimento Global/estatística & dados numéricos , Umidade , Indonésia , Chuva , Refúgio de Vida Selvagem , Imagens de Satélites , Especificidade da Espécie , Temperatura , Fatores de TempoRESUMO
This study assessed the fate of a Salmonella enterica cocktail (S. Typhimurium, S. Enteritidis, S. Newport, S. Agona and S. Anatum; initial counts 3.5 log CFU/g) in minimally processed sliced chard, broccoli and red cabbage at 16 conditions of different temperature (7, 14, 21 and 37 °C) and relative humidity (RH; 15, 35, 65 and 95%) over six days (144 h). Linear regression was used to estimate the rate change of Salmonella in cut vegetables as a function of temperature and relative humidity (RH). R2 value of 0.85, 0.87, and 0.78 were observed for the rates of change in chard, broccoli, and red cabbage, respectively. The interaction between temperature and RH was significant in all sliced vegetables. Higher temperatures and RH values favored Salmonella growth. As temperature or RH decreased, the rate of S. enterica change varied by vegetable. The models developed here can improve risk management of Salmonella in fresh cut vegetables.
Assuntos
Beta vulgaris , Brassica , Salmonella enterica , Temperatura , Microbiologia de Alimentos , Contaminação de Alimentos/análise , Umidade , Contagem de Colônia Microbiana , Salmonella , VerdurasRESUMO
This study aimed to determine the influence of heat stress during the dry period on milk yield and reproductive performance of Holstein cows in a hot environment. Breeding and milk production records of cows, as well as meteorological data between 2017 and 2020 from a commercial dairy herd (n = 12,102 lactations), were used to determine the relationship between climatic conditions during the dry period (average of the temperature-humidity index (THI) at the beginning, middle, and end of the dry period) and reproductive efficiency and milk yield traits. THI was divided into < 70 (no heat stress), 70-80 (moderate heat stress), and > 80 (severe heat stress). First-service pregnancy rate of cows decreased (P < 0.01) with increasing hyperthermia during the dry period (9.5, 7.3, and 3.4% for THI < 70, 70-80, and > 80, respectively). All-service pregnancy rate was highest (P < 0.01) for cows not undergoing heat stress during the dry period (60.2%) and lowest (42.6%) for cows with severe heat stress during the dry period. Cows not experiencing heat stress during the dry period required a mean ± SD of 5.6 ± 3.8 services per pregnancy compared with 6.5 ± 3.6 (P < 0.01) for cows subjected to THI > 80 during the dry period. Cows not suffering heat stress during the dry period produced more (P < 0.01) 305-day milk (10,926 ± 1206 kg) than cows subjected to moderate (10,799 ± 1254 kg) or severe (10,691 ± 1297 kg) heat stress during the dry period. Total milk yield did not differ (P > 0.10) between cows not undergoing heat stress (13,337 ± 3346 kg) and cows subjected to severe heat stress during the dry period (13,911 ± 4018 kg). It was concluded that environmental management of dry cows during hot months is warranted to maximize reproductive performance and milk yield in the following lactation.
Assuntos
Resposta ao Choque Térmico , Umidade , Lactação , Leite , Reprodução , Animais , Bovinos/fisiologia , Feminino , Reprodução/fisiologia , Resposta ao Choque Térmico/fisiologia , Gravidez , Transtornos de Estresse por Calor/veterinária , Transtornos de Estresse por Calor/fisiopatologia , Temperatura AltaRESUMO
The housing conditions of laboratory mice must be strictly controlled in order to reduce the impact of pathophysiological changes that affect animal health and welfare, possibly resulting in increased variability within experimental results. One way to improve the activity and survival of laboratory mice is to provide nesting material. The objective of this study was to determine if nest-building quality could be used to detect changes in murine mating behaviour in a rodent facility under controlled conditions. Nesting scores of 847 cages with monogamous pairs from three different genetic backgrounds (129, B6 and BALB/c) of both sexes were correlated with 18 predefined variables. The effects on nest quality were evaluated using descriptive data analysis, correspondence analysis and ordinal logistic model fitting. The results showed a strong relationship between nest quality and nest position. Humidity, genetic background, cage change and the number and age of pups in the cage affected the nest-building scores. The most important indicators were cage change and relative humidity, both of which exerted significant negative effects on nest-building quality. Even though the criteria were well defined, the observer could still influence nest score appraisal. However, in a long-term observational study, observers could improve their assessment by training and acquiring greater experience in score assignment. Nest-building scores are easy to assess in the cage, with little discomfort to the animal. Moreover, the nest score is a valid indicator of the health and well-being of laboratory mice and can provide valuable support in the management of animal facilities.
Assuntos
Abrigo para Animais , Comportamento de Nidação , Animais , Feminino , Masculino , Camundongos/fisiologia , Camundongos Endogâmicos BALB C , Comportamento Sexual Animal/fisiologia , Criação de Animais Domésticos/métodos , Umidade , Bem-Estar do AnimalRESUMO
High Energy Ball-Milling (HEBM) modifies starchs' granule morphology, physicochemical properties, and chemical structure. However, understanding how the HEBM changes the starch chemical structure is necessary to control these modifications. Therefore, this study aimed to investigate the changes in potato starch's long- and short-range molecular order during HEBM at different environmental conditions such as oxygen (Air) and humidity content. Due to the correlation between the starch modification and the energy supplied (Esupp) by the HEBM, Burgio's equation was used to calculate this energy. The starch transformation was followed by X-ray diffraction, Fourier Transform-Infrared Spectroscopy, and Raman spectroscopy. A Principal Component Analysis (PCA) was conducted to reduce the HEBM variables. PAC analysis demonstrated that the different oxygen-humidity conditions do not affect the HEBM of potato starch. Based on the starch chemical structure transformation correlated with Esupp during HEBM, four stages were observed: orientation, modification, mechanolysis, and over-destruction. It was identified for the first time that at low milling energy (<1.5 kJ/g, orientation stage), the glycosidic rings change their orientation, and starch-water interaction increases while the starch's organization reduces. Ergo, the potato starch could be more susceptible to chemical modifications during the first two stages.