Non-thermal effects of direct electric fields and alternating electromagnetic fields(EMF)have been successfully used in a number of studies and applications in agriculture and biotechnology.Among different kinds of hi...Non-thermal effects of direct electric fields and alternating electromagnetic fields(EMF)have been successfully used in a number of studies and applications in agriculture and biotechnology.Among different kinds of high strength EMF generators,the Tesla transformer(TT)is known as a widely applied,low cost,and troubleproof device,which generates EMF in the range of 2-8 MHz.Despite of a number of developed and perspective applications of high strength EMFs in agriculture and biotechnology,the EMFs generated by TT,as well as the 1-50 MHz range of high strength EMF still remain unexplored in the fields of plant physiology,ultrastructure studies and biochemistry.In this work,we have shown that TT-EMFs(4 MHz)induced fast stem and petiole bending,disappearance of cell organelles,vacuolar membranes,and increase of a non-photochemical chlorophyll fluorescence quenching in petioles.It is intriguing that such fatal effects can be evoked in plants by EMFs which are well known as harmless for man at the applied strength and frequency.展开更多
A cheap method allowing fabrication of biocompatible,ultra-small(2-10 nm)and fluorescent(λ_(em)=425-500 nm)nanohybrids(NHs)from coffee wastes is reported.The gadolinium-doped nanohybrids(GDNHs)or gadolinium-free carb...A cheap method allowing fabrication of biocompatible,ultra-small(2-10 nm)and fluorescent(λ_(em)=425-500 nm)nanohybrids(NHs)from coffee wastes is reported.The gadolinium-doped nanohybrids(GDNHs)or gadolinium-free carbon dots(GFCDs)can be synthesized in a domestic microwave oven according to green synthesis principles.Hydrodynamic sizes,chemical composition,impact on proton magnetic resonance relaxation time and optical properties of the GDNHs and GFCDs were studied in details and compared.In particular,doping of the NHs with Gd^(3+)ions,up to 1.87%w/w of gadolinium per particles’weight,will allow their application for magnetic resonance imaging(MRI).Furthermore,cell culture tests on human adenocarcinomic alveolar basal epithelial cells line(A549)have shown high biocompatibility of the GDNHs and in a wide concentration range 100-1000μg/ml.展开更多
Maximal and partial quantum yields of photosystem II(Fv/Fm and Fv–/Fp)in Phaseolus vulgaris leaves were determined in response to the turning on saturating and low(undersaturating)actinic light,accordingly.Measuring ...Maximal and partial quantum yields of photosystem II(Fv/Fm and Fv–/Fp)in Phaseolus vulgaris leaves were determined in response to the turning on saturating and low(undersaturating)actinic light,accordingly.Measuring lights(ML)of blue,green,and red colors were applied simultaneously using a novel method of the polychromatic fast Fourier transforming pulse amplitude modulation(FFT PAM)chlorophyll fluorometry.Colors of ML were cross-combined with the colors of low and saturating actinic light.Fv/Fm values measured with the green ML were found to be close to that of red light,whereas application of blue ML leads to lower Fv/Fm.In addition,5-nm resolved excitation spectra were measured to evaluate the dependence between red/far red fluorescence ratios(peak height based–F685/F730,and deconvolved peak square based–F685sq/F730sq)and wavelength of the excitation light.It demonstrates that chlorophyll fluorescence ratio red/far red may be dependent on the spectral absorbance of chlorophyll.The data obtained confirm the results of the previous studies which explain high photosynthetic activity of the green light in terms of redistribution of absorbed quanta throughout thickness of the leaf,thus suggesting possible advisability of green light application in greenhouse lighting,especially for the plants having thick leaves.展开更多
基金Southern Federal University(Rostov-on-Don)for the grant(N 213.01-07-2014/06PChVG)provided to achieve the aims of the present research.
文摘Non-thermal effects of direct electric fields and alternating electromagnetic fields(EMF)have been successfully used in a number of studies and applications in agriculture and biotechnology.Among different kinds of high strength EMF generators,the Tesla transformer(TT)is known as a widely applied,low cost,and troubleproof device,which generates EMF in the range of 2-8 MHz.Despite of a number of developed and perspective applications of high strength EMFs in agriculture and biotechnology,the EMFs generated by TT,as well as the 1-50 MHz range of high strength EMF still remain unexplored in the fields of plant physiology,ultrastructure studies and biochemistry.In this work,we have shown that TT-EMFs(4 MHz)induced fast stem and petiole bending,disappearance of cell organelles,vacuolar membranes,and increase of a non-photochemical chlorophyll fluorescence quenching in petioles.It is intriguing that such fatal effects can be evoked in plants by EMFs which are well known as harmless for man at the applied strength and frequency.
基金the support of EU Horizon 2020 Research and Innovation Staff Exchange Programme(RISE)under Marie Skłodowska-Curie Action(project 101008159“UNAT”).
文摘A cheap method allowing fabrication of biocompatible,ultra-small(2-10 nm)and fluorescent(λ_(em)=425-500 nm)nanohybrids(NHs)from coffee wastes is reported.The gadolinium-doped nanohybrids(GDNHs)or gadolinium-free carbon dots(GFCDs)can be synthesized in a domestic microwave oven according to green synthesis principles.Hydrodynamic sizes,chemical composition,impact on proton magnetic resonance relaxation time and optical properties of the GDNHs and GFCDs were studied in details and compared.In particular,doping of the NHs with Gd^(3+)ions,up to 1.87%w/w of gadolinium per particles’weight,will allow their application for magnetic resonance imaging(MRI).Furthermore,cell culture tests on human adenocarcinomic alveolar basal epithelial cells line(A549)have shown high biocompatibility of the GDNHs and in a wide concentration range 100-1000μg/ml.
基金We are grateful to Ministry of education and science of the Russian Federation for the financial support(grant No 6.6222.2017/8.9).The project was performed with the equipment of Multiaccess Center‘‘Biotechnology,Biomedicine and Environmental Monitoring”,Laboratory of plant ecology and physiology of Academy of Biology and Biotechnology of Southern Federal University(Rostov-on-Don).Researchers are also grateful to Russian Information-Analytical andWater Management Research Center for help in performing this study.
文摘Maximal and partial quantum yields of photosystem II(Fv/Fm and Fv–/Fp)in Phaseolus vulgaris leaves were determined in response to the turning on saturating and low(undersaturating)actinic light,accordingly.Measuring lights(ML)of blue,green,and red colors were applied simultaneously using a novel method of the polychromatic fast Fourier transforming pulse amplitude modulation(FFT PAM)chlorophyll fluorometry.Colors of ML were cross-combined with the colors of low and saturating actinic light.Fv/Fm values measured with the green ML were found to be close to that of red light,whereas application of blue ML leads to lower Fv/Fm.In addition,5-nm resolved excitation spectra were measured to evaluate the dependence between red/far red fluorescence ratios(peak height based–F685/F730,and deconvolved peak square based–F685sq/F730sq)and wavelength of the excitation light.It demonstrates that chlorophyll fluorescence ratio red/far red may be dependent on the spectral absorbance of chlorophyll.The data obtained confirm the results of the previous studies which explain high photosynthetic activity of the green light in terms of redistribution of absorbed quanta throughout thickness of the leaf,thus suggesting possible advisability of green light application in greenhouse lighting,especially for the plants having thick leaves.
