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Natural SiO2 nanoparticles (SiO2-NPs) are widely distributed in the environment, and at the same time, synthetic SiO2-NP may be applied in agriculture. Evaluations of physiological responses to SiO2-NPs treatment of plants are controversial. They are often performed at adaxial leaf sides whereas NPs permeate leaf tissues through stomata located at the abaxial leaf side in the majority of bifacial plants. We measured coefficients of the functional dorsoventral asymmetry of NPs-stressed Сhelidonium majus leaves, S, by values of the CO2 assimilation rate (SPN), dark respiration (SR), maximal and operating quantum yields of photosystem II (SFv/Fm, SFv'/Fm'; using PAM-fluorometry), and oxygen coefficients of photosynthesis (SΨO2; using photoacoustics). The results indicated that SPN and SΨO2 were significantly influenced by SiO2-NPs treatment, since PN and ΨO2 were declining more markedly when the light was directed to the abaxial side of leaves compared to the adaxial side. Overall, SiO2-NPs-induced stress increased 'anoxygenity' of photosynthesis. [ABSTRACT FROM AUTHOR] more...

Non-destructive methods for the assessment of photosynthetic parameters of plants are widely applied to evaluate rapidly the photosynthetic performance, plant health, and shifts in plant productivity induced by environmental and cultivation conditions. Most of these methods are based on measurements of chlorophyll fluorescence kinetics, particularly on pulse modulation (PAM) fluorometry. In this paper, fluorescence methods are critically discussed in regard to some their possibilities and limitations inherent to vascular plants and microalgae. Attention is paid to the potential errors related to the underestimation of thylakoidal cyclic electron transport and anoxygenic photosynthesis. PAM-methods are also observed considering the color-addressed measurements. Photoacoustic methods are discussed as an alternative and supplement to fluorometry. Novel Fourier modifications of PAM-fluorometry and photoacoustics are noted as tools allowing simultaneous application of a dual or multi frequency measuring light for one sample., Competing Interests: Conflict of interestThe authors declare that there are no conflicts of interest., (© Prof. H.S. Srivastava Foundation for Science and Society 2022, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.) more...

Objective: To study the etiopathogenetic and clinical features of inpatients with venous thrombosis., Material and Methods: The analysis of 25 medical cases of patients with venous thrombosis was performed., Results: Cerebral venous thrombosis most often developed in females (88%), the average age was 36 years. The most frequent localization of thrombosis was observed in the transverse sinus, as independently (40%) and in combination with thrombosis of other sinuses. Headache was the main clinical sign that could be a single feature or accompanied by other neurological symptoms. In 13 patients (86.6%), multiple polymorphisms in blood coagulation genes (more than 4 mutations) were identified. All patients were prescribed anticoagulant therapy. In all cases, there were positive dynamics of the patients' condition, in the form of a decrease in the intensity of headache or complete regression of cephalalgia, neurological symptoms regressed in 20 patients (80%), there was no fatal outcome., Conclusion: If central venous thrombosis is detected, especially in young people, an analysis for genetic polymorphism of the blood coagulation system and the folate cycle should be carried out. This will allow timely development of secondary prevention and reduce the risk of recurrent thrombosis. more...