Box populations of Drosophila melanogaster are characterized by two types of periodical fluctuations of numbers: with low and high frequency. High frequency fluctuations are determined by existence of preimago and imago stages and subsequent delay in density-dependent limitation of imago reproduction, duration of which is determined by time of preimago stage. The period of these fluctuations should be limited within two generation, that is confirmed by experimental data. Low frequency fluctuations with the period of 13-15 generations are the result of ecological density-dependent effect. In this case during pick density one can observe continuous degradation of population (i.e. decrease in fecundity and life time of imago) and following decrease in numbers. Temporary changes in fecundity of females and their offspring of the second generation are positively correlated with low frequency fluctuations in numbers. Such relationships show the possibility of density-dependent, cyclic, genetic changes in fecundity connected with fluctuations in numbers. It means that at the phase of growth in numbers when the density is still low, the selection is directed to the individuals with high fecundity sensible to overpopulation. The phase of decline in numbers is connected with high density and selection directed to the individuals with low fecundity in low density populations. The changes in genetic structure of fluctuating population lead to the weakening of this fluctuations and to the maintaining of population under such conditions.
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Talanta
January 2025
School of Material Science and Engineering, Shanghai University of Engineering Science, Shanghai, 201620, PR China. Electronic address:
Flexible sweat sensors play a crucial role in health monitoring and disease prevention by enabling real-time, non-invasive assessment of human physiological conditions. Sweat contains a variety of biomarkers, offering valuable insights into an individual's health status. In this study, we developed an advanced flexible electrochemical sensor featuring reduced graphene oxide (rGO)-based electrodes, modified with a composite material comprising nitrogen and sulfur co-doped holey graphene (HG) and MXene, with in-situ-grown TiO nanoparticles on the MXene.
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Swiss Federal Institute of technology in Lausanne, Lausanne, Vaud, Switzerland.
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Ens de Lyon, Université Lyon, CNRS, Laboratoire de Physique, F-69342 Lyon, France.
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Quantinuum, 303 S. Technology Court, Broomfield, Colorado 80021, USA.
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January 2025
Department of Chemistry, Hankuk University of Foreign Studies, Yongin 17035, Republic of Korea.
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