Presently we continue our studies of the quantum mechanism of light energy transmission in the form of excitons by axisymmetric nanostructures with electrically conductive walls. Using our theoretical model, we analyzed the light energy transmission by biopolymers forming optical channels within retinal Müller cells. There are specialized intermediate filaments (IF) 10-18nm in diameter, built of electrically conductive polypeptides. Presently, we analyzed the spectral selectivity of these nanostructures. We found that their transmission spectrum depends on their diameter and wall thickness. We also considered the classical approach, comparing the results with those predicted by the quantum mechanism. We performed experimental measurements on model quantum waveguides, made of rectangular nanometer-thick chromium (Cr) tracks. The optical spectrum of such waveguides varied with their thickness. We compared the experimental absorption/transmission spectra with those predicted by our model, with good agreement between the two. We report that the observed spectra may be explained by the same mechanisms as operating in metal nanolayers. Both the models and the experiment show that Cr nanotracks have high light transmission efficiency in a narrow spectral range, with the spectral maximum dependent on the layer thickness. Therefore, a set of intermediate filaments with different geometries may provide light transmission over the entire visible spectrum with a very high (~90%) efficiency. Thus, we believe that high contrast and visual resolution in daylight are provided by the quantum mechanism of energy transfer in the form of excitons, whereas the ultimate retinal sensitivity of the night vision is provided by the classical mechanism of photons transmitted by the Müller cell light-guides.
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http://dx.doi.org/10.1016/j.jphotobiol.2017.06.001 | DOI Listing |
Nanoscale
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School of Materials and Chemistry, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai 200093, China.
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National Synchrotron Light source II, Brookhaven National Laboratory, Upton, New York 11973, United States.
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January 2025
Institute of Preventive Medicine, School of Public Health, Dali University, Yunnan Key Laboratory of Screening and Research on Anti-pathogenic Plant Resources from Western Yunnan, Yunnan Key Laboratory of Zoonotic Disease Cross-border Prevention and Quarantine, Dali, Yunnan 671000, China. E-mail:
The family has seen an explosive expansion in its host range in recent years, yet the evolutionary trajectory of this zoonotic pathogen remains largely unknown. The emergence of rat hepatitis E virus (HEV) has introduced a new public health threat due to its potential for zoonotic transmission. This study investigated 2 464 wild small mammals spanning four animal orders, eight families, 21 genera, and 37 species in Yunnan Province, China.
View Article and Find Full Text PDFPhysiol Plant
January 2025
Department of Plant Anatomy, Institute of Biology, Faculty of Science, ELTE Eötvös Loránd University, Budapest, Hungary.
Investigating the effects of drought stress and subsequent recovery on the structure and function of chloroplasts is essential to understanding how plants adapt to environmental stressors. We investigated Ctenanthe setosa (Roscoe) Eichler, an ornamental plant that can tolerate prolonged drought periods (40 and 49 days of water withdrawal). Conventional biochemical, biophysical, physiological and (ultra)structural methods combined for the first time in a higher plant with in vivo small-angle neutron scattering (SANS) were used to characterize the alterations induced by drought stress and subsequent recovery.
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January 2025
Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Nijmegen Medical Centre, 6500HB, Nijmegen, the Netherlands.
Recent studies argue for a novel concept of the role of chromatin as a carrier of epigenetic memory through cellular and organismal generations, defining and coordinating gene activity states and physiological functions. Environmental insults, such as exposures to unhealthy diets, smoking, toxic compounds, and infections, can epigenetically reprogram germ-line cells and influence offspring phenotypes. This review focuses on intergenerational and transgenerational epigenetic inheritance in different plants, animal species and humans, presenting the up-to-date evidence and arguments for such effects in light of Darwinian and Lamarckian evolutionary theories.
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