In the Drosophila population the individuals of medium, small and large size prevail in spring, summer and autumn correspondingly. Such differences are genetically determined. Small individuals are characterized by the highest modification variability while the large individuals--by the lowest one. Genotypic heterogeneity of the population was also found in the body size of individuals, which is the highest in summer and the lowest in autumn. Dynamics of the individual sizes and of genetic heterogeneity is determined by radical seasonal changes in genotypic composition of the population. Such reconstruction influences the substantial part of gene pool, which defines the dimension of individuals. One of the possible reasons of this process is an integral selective action of the population density and temperature. It provides the regulation of variations in numbers and adaptation to the seasonal changes in life conditions.
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Trop Med Health
January 2025
School of Medicine, Private Technical University of Loja, Loja, 110101, Ecuador.
Introduction: Dengue is one of the most widespread arboviruses in Latin America and is now affecting areas previously free of transmission. The COVID-19 pandemic and climatic variations appear to have affected the incidence of the disease, abundance of vectors and health programs related to dengue in some countries.
Objective: To analyze the epidemiology of dengue in Paltas, Ecuador (2016-2022), compare the periods before and during the COVID-19 pandemic, examine entomological reports and discuss the possible implications of the COVID-19 pandemic and climatic variations.
Nature
January 2025
School of Life Sciences, Hebei University, Baoding, China.
Extreme droughts generally decrease productivity in grassland ecosystems with negative consequences for nature's contribution to people. The extent to which this negative effect varies among grassland types and over time in response to multi-year extreme drought remains unclear. Here, using a coordinated distributed experiment that simulated four years of growing-season drought (around 66% rainfall reduction), we compared drought sensitivity within and among six representative grasslands spanning broad precipitation gradients in each of Eurasia and North America-two of the Northern Hemisphere's largest grass-dominated regions.
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January 2025
Aquatic Ecology, Department of Biology, Lund University, Lund, Sweden.
Environmental variation has long been considered a key driver of evolutionary change, predicted to shape different strategies, such as genetic specialization, plasticity, or bet-hedging to maintain fitness. However, little evidence is available with regards to how the periodicity of stressors may impact fitness across generations. To address this gap, I conducted a reciprocal split-brood experiment using the freshwater crustacean, Daphnia magna, and an ecologically relevant environmental stressor, ultraviolet radiation (UVR).
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January 2025
Division of Genetics, Indian Agricultural Research Institute, New Delhi, India.
With climate change projections indicating an increase in the frequency of extreme heat events and irregular rainfall patterns globally, the threat to global food security looms large. Terminal heat stress, which occurs during the critical reproductive stage, significantly limits lentil productivity. Therefore, there is an urgent need to improve lentil's resilience to heat stress to sustain production.
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January 2025
Dermatology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Emilia-Romagna, Italy.
Objectives: Scabies infestation, caused by the mite, has recently emerged as a public health concern in Western nations, with increased incidence worldwide. In Bologna, Italy, local health authorities report a rise in scabies diagnoses, although detailed data are limited. This study aimed to analyse the temporal trends of scabies cases diagnosed at S.
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