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1.
Vavilovskii Zhurnal Genet Selektsii ; 28(1): 63-73, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38465247

ABSTRACT

Improving the nutritional value of grain sorghum, a drought- and heat-tolerant grain crop, is an important task in the context of global warming. One of the reasons for the low nutritional value of sorghum grain is the resistance of its storage proteins (kafirins) to proteolytic digestion, which is due, among other things, to the structural organization of protein bodies, in which γ-kafirin, the most resistant to proteases, is located on the periphery, encapsulating more easily digested α-kafirins. The introduction of genetic constructs capable of inducing RNA silencing of the γ-kafirin (gKAF1) gene opens up prospects for solving this problem. Using Agrobacterium-mediated genetic transformation of immature embryos of the grain sorghum cv. Avans we have obtained a mutant with improved digestibility of endosperm proteins (up to 92 %) carrying a genetic construct for RNA silencing of the gKAF1 gene. The goal of this work was to study the stability of inheritance of the introduced genetic construct in T2-T4 generations, to identify the number of its copies, as well as to trace the manifestation of agronomically valuable traits in the offspring of the mutant. The mutant lines were grown in experimental plots in three randomized blocks. The studied lines were characterized by improved digestibility of kafirins, a modified type of endosperm, completely or partially devoid of the vitreous layer, an increased percentage of lysine (by 75 %), reduced plant height, peduncle length, 1000-grains weight, and grain yield from the panicle. In T2, a line with monogenic control of GA resistance was selected. qPCR analysis showed that in different T3 and T4 plants, the genetic construct was present in 2-4 copies. In T3, a line with a high digestibility of endosperm proteins (81 %) and a minimal decrease in agronomically valuable traits (by 5-7 %) was selected.

2.
Nat Commun ; 13(1): 170, 2022 Jan 10.
Article in English | MEDLINE | ID: mdl-35013380

ABSTRACT

Ultra-intense MeV photon and neutron beams are indispensable tools in many research fields such as nuclear, atomic and material science as well as in medical and biophysical applications. For applications in laboratory nuclear astrophysics, neutron fluxes in excess of 1021 n/(cm2 s) are required. Such ultra-high fluxes are unattainable with existing conventional reactor- and accelerator-based facilities. Currently discussed concepts for generating high-flux neutron beams are based on ultra-high power multi-petawatt lasers operating around 1023 W/cm2 intensities. Here, we present an efficient concept for generating γ and neutron beams based on enhanced production of direct laser-accelerated electrons in relativistic laser interactions with a long-scale near critical density plasma at 1019 W/cm2 intensity. Experimental insights in the laser-driven generation of ultra-intense, well-directed multi-MeV beams of photons more than 1012 ph/sr and an ultra-high intense neutron source with greater than 6 × 1010 neutrons per shot are presented. More than 1.4% laser-to-gamma conversion efficiency above 10 MeV and 0.05% laser-to-neutron conversion efficiency were recorded, already at moderate relativistic laser intensities and ps pulse duration. This approach promises a strong boost of the diagnostic potential of existing kJ PW laser systems used for Inertial Confinement Fusion (ICF) research.

3.
Sci Rep ; 8(1): 17895, 2018 Dec 17.
Article in English | MEDLINE | ID: mdl-30559388

ABSTRACT

Optical generation of compact magnetized plasma structures is studied in the moderate intensity domain. A sub-ns laser beam irradiated snail-shaped targets with the intensity of about 1016 W/cm2. With a neat optical diagnostics, a sub-megagauss magnetized plasmoid is traced inside the target. On the observed hydrodynamic time scale, the hot plasma formation achieves a theta-pinch-like density and magnetic field distribution, which implodes into the target interior. This simple and elegant plasma magnetization scheme in the moderate-intensity domain is of particular interest for fundamental astrophysical-related studies and for development of future technologies.

4.
Phys Rev Lett ; 117(23): 235002, 2016 Dec 02.
Article in English | MEDLINE | ID: mdl-27982626

ABSTRACT

Experiments have been performed evidencing significant stimulated Raman sidescattering (SRS) at large angles from the density gradient. This was achieved in long scale-length high-temperature plasmas in which two beams couple to the same scattered electromagnetic wave further demonstrating for the first time this multiple-beam collective SRS interaction. The collective nature of the coupling and the amplification at large angles from the density gradient increase the global SRS losses and produce light scattered in novel directions out of the planes of incidence of the beams. These findings obtained in plasmas conditions relevant of inertial confinement fusion experiments similarly apply to the more complex geometry of these experiments where anomalously large levels of SRS were measured.

5.
Article in Russian | MEDLINE | ID: mdl-27029119

ABSTRACT

AIM: Study the composition of plant extracts using high-performance liquid chromatography. (HPLC) and evaluation of their antimicrobial effect against Vibrio cholerae El Tor. MATERIALS AND METHODS: Qualitative and quantitative composition of plant extracts was studied using HPLC. Determination of sensitivity of microorganisms to plant extracts was carried out by diffusion into agar method and serial dilutions method. RESULTS: Antibacterial effect of water, water-alcohol and acetone extracts of roots of Limonium gmelinii L., Berberis vulgaris L. and Glycyrrhiza glabra L. was studied. The most effective methods of extraction of biologically active substances, possessing antimicrobial effect against various strains of V. cholerae El Tor, were determined. CONCLUSION: The use of HPLC allowed to establish the presence of catechines, alkaloids protoberberines and glycyrrhizic acid in xtracts, possessing antimicrobial effect against V. cholera El Tor strains.


Subject(s)
Anti-Bacterial Agents/chemistry , Berberine Alkaloids/chemistry , Catechols/chemistry , Glycyrrhizic Acid/chemistry , Plant Extracts/chemistry , Vibrio cholerae/drug effects , Acetone/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Berberine Alkaloids/isolation & purification , Berberine Alkaloids/pharmacology , Berberis/chemistry , Catechols/isolation & purification , Catechols/pharmacology , Chromatography, High Pressure Liquid , Ethanol/chemistry , Glycyrrhiza/chemistry , Glycyrrhizic Acid/isolation & purification , Glycyrrhizic Acid/pharmacology , Microbial Sensitivity Tests , Plumbaginaceae/chemistry , Solvents/chemistry , Vibrio cholerae/growth & development , Water/chemistry
6.
Nat Commun ; 5: 4158, 2014 Jun 18.
Article in English | MEDLINE | ID: mdl-24938756

ABSTRACT

Stimulated Raman backscattering (SRS) has many unwanted effects in megajoule-scale inertially confined fusion (ICF) plasmas. Moreover, attempts to harness SRS to amplify short laser pulses through backward Raman amplification have achieved limited success. In high-temperature fusion plasmas, SRS usually occurs in a kinetic regime where the nonlinear response of the Langmuir wave to the laser drive and its host of complicating factors make it difficult to predict the degree of amplification that can be achieved under given experimental conditions. Here we present experimental evidence of reduced Landau damping with increasing Langmuir wave amplitude and determine its effects on Raman amplification. The threshold for trapping effects to influence the amplification is shown to be very low. Above threshold, the complex SRS dynamics results in increased amplification factors, which partly explains previous ICF experiments. These insights could aid the development of more efficient backward Raman amplification schemes in this regime.

7.
Phys Rev Lett ; 111(23): 235006, 2013 Dec 06.
Article in English | MEDLINE | ID: mdl-24476284

ABSTRACT

An experimental program was designed to study the most important issues of laser-plasma interaction physics in the context of the shock ignition scheme. In the new experiments presented in this Letter, a combination of kilojoule and short laser pulses was used to study the laser-plasma coupling at high laser intensities for a large range of electron densities and plasma profiles. We find that the backscatter is dominated by stimulated Brillouin scattering with stimulated Raman scattering staying at a limited level. This is in agreement with past experiments using long pulses but laser intensities limited to 2×10(15) W/cm2, or short pulses with intensities up to 5×10(16) W/cm2 as well as with 2D particle-in-cell simulations.

8.
Bioorg Khim ; 37(5): 679-84, 2011.
Article in Russian | MEDLINE | ID: mdl-22332364

ABSTRACT

The molecular complexation of adenine and guanine with hederagenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-alpha-L-arabinopyranoside (alpha-hederin) and its 28-O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-O-beta-D-glucopyranosyl ester (hederasaponin C) was investigated for the first time using the method of electrospray ionization mass spectrometry. Guanine forms complexes more diverse in composition than adenine.


Subject(s)
Adenine/chemistry , Glycosides/chemistry , Guanine/chemistry , Oleanolic Acid/analogs & derivatives , Saponins/chemistry , Triterpenes/chemistry , Hedera/chemistry , Molecular Structure , Nucleic Acids/chemistry , Oleanolic Acid/chemistry , Spectrometry, Mass, Electrospray Ionization
9.
Phys Chem Chem Phys ; 11(47): 11140-5, 2009 Dec 21.
Article in English | MEDLINE | ID: mdl-20024383

ABSTRACT

In the present paper the underpotential deposition (UPD) of lithium on Au(111) from 0.5 mol L(-1) LiTFSA in the air- and water stable ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide, [Py(1,4)]TFSA, has been investigated by cyclic voltammetry (CV) and in situ scanning tunneling microscopy (STM). The pure [Py(1,4)]TFSA was found to be inert in the potential regime investigated. The results show that the lithium UPD on Au(111) in [Py(1,4)]TFSA begins at potentials considerably positive to the electrode potential of bulk deposition and follows a layer-by-layer mechanism with the formation of at least two monolayers. A large number of monoatomically deep pits appear when the potential reaches positive values, which is an indication that a Li-Au alloy was formed.

10.
Phys Rev Lett ; 102(19): 195005, 2009 May 15.
Article in English | MEDLINE | ID: mdl-19518967

ABSTRACT

This Letter presents first experimental results of the laser imprint reduction in fusion scale plasmas using a low-density foam layer. The experiments were conducted on the LIL facility at the energy level of 12 kJ with millimeter-size plasmas, reproducing the conditions of the initial interaction phase in the direct-drive scheme. The results include the generation of a supersonic ionization wave in the foam and the reduction of the initial laser fluctuations after propagation through 500 mum of foam with limited levels of stimulated Brillouin and Raman scattering. The smoothing mechanisms are analyzed and explained.

11.
J Phys Chem B ; 110(12): 6250-6, 2006 Mar 30.
Article in English | MEDLINE | ID: mdl-16553441

ABSTRACT

The electrodeposition of silicon on Au(111) was investigated by cyclic voltammety (CV) and by in situ scanning tunneling microscopy (STM) in the room temperature ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide with a SiCl(4) concentration of 0.1 mol/L. A main reduction process begins in the cyclic voltammogram at about -1800 mV versus ferrocene/ferrocinium, which is correlated to the electrodeposition of elemental semiconducting silicon. It has been found that at an electrode potential more negative than the open circuit potential (OCP), the Au(111) surface is subject to a restructuring/reconstruction both in the case of the pure ionic liquid and in the presence of SiCl(4). The first STM-probed silicon islands with 150-450 pm in height appear at about -1700 mV versus ferrocene/ferrocinium. Their lateral and vertical growth leads to the formation of a rough layer with silicon islands of up to 1 nm in height. At about -1800 mV the islands merge and form silicon agglomerates. In situ I/U tunneling spectroscopy reveals a band gap of 1.1 +/- 0.2 eV for layers of about 5 nm in height, a value that has to be expected for semiconducting silicon.

13.
Eksp Klin Gastroenterol ; (5): 103-4, 130, 2002.
Article in Russian | MEDLINE | ID: mdl-12619590

ABSTRACT

Our studies demonstrated that chronic opisthorchosis with a skin syndrome is accompanied by a severer clinical course. The course of rehabilitation measures with the use of resort recreation (mud-bad cure) combined with traditional treatment stages makes it possible to considerably enhance the efficiency of treatment of both opisthorchosis and its skin manifestations, and should be applied more often in practice.


Subject(s)
Opisthorchiasis/rehabilitation , Opisthorchiasis/therapy , Skin Diseases, Parasitic/complications , Humans , Opisthorchiasis/complications
14.
Talanta ; 44(10): 1735-47, 1997 Oct.
Article in English | MEDLINE | ID: mdl-18966913

ABSTRACT

Using the model of ideally associated solution, the effect of ion association of the ion exchanger sites with main and foreign counterions on the selectivity of ISEs based on liquid ion exchangers has been considered. Equations which describe the potentiometric selectivity coefficient as a function of ion association constants in the membrane phase and of standard free energies of transfer of the determined and foreign ions from water to the membrane are obtained for the following main cases: (a) the determined and foreign ions are single-charged; (b) the determined ion is double-charged and the foreign ion is single-charged. It is shown that in the case of single-charged main and foreign ions, the ratio of the ion association constants has a great effect on the potentiometric selectivity of membranes, only if the ion exchanger sites produce less strong associates with the determined counterion as compared with the foreign one. Otherwise, this effect is insignificant. The selectivity for double-charged ions should increase, other things being equal, as the first constant of association of these ions with the ion exchanger sites increases. The effect of producing ion triplets of the type I(2)R((+/-)) on the selectivity of ISEs is also considered. Experimental data are presented which illustrate the effect of the nature of the ion exchanger on the potentiometric selectivity. Some procedures employing the factor of ion association for increasing the potentiometric selectivity of liquid ion exchange membranes are considered.

16.
Lik Sprava ; (5-6): 181-4, 1994.
Article in Russian | MEDLINE | ID: mdl-7831896

ABSTRACT

Formation of a healthy life style is a complex socioeconomic task which is to be solved at the level of the state, public health care agencies as well as at the individual level. Attainment of this objective will require a complex approach to each individual taken separately.


Subject(s)
Health Promotion/trends , Life Style , Health Promotion/methods , Humans , Public Health/methods , Public Health/trends , Ukraine
17.
Lik Sprava ; (9): 30-4, 1992 Sep.
Article in Russian | MEDLINE | ID: mdl-1481499

ABSTRACT

The immune and fibrinolytic systems were studied in 55 patients with postpneumonic lung abscess; 17 of them were operated on. Revealed were reductions of the number and functional activity of the T-cell immunity and a systemic-regional fibroanalysis data (high fibrinolytic activity in the systemic circulation and bronchial lumen; high activity in the blood of the resected lung portion). High activator activity of the sputum and its absence in the pus of the abscess cavity evidence that the source of the plasminogen activator is the bronchial wall not the destructed pulmonary tissue.


Subject(s)
Fibrinolysis , Lung Abscess/blood , Lung Abscess/immunology , Pneumonia/blood , Pneumonia/immunology , B-Lymphocytes/immunology , Bronchoalveolar Lavage Fluid/cytology , Bronchoalveolar Lavage Fluid/immunology , Humans , Immunity, Cellular , Immunoglobulins/blood , Leukocyte Count , Lung Abscess/etiology , Macrophages, Alveolar/immunology , Pneumonia/complications , Sputum/cytology , Sputum/immunology , T-Lymphocytes/immunology
18.
Lik Sprava ; (3): 73-5, 1992 Mar.
Article in Russian | MEDLINE | ID: mdl-1413696

ABSTRACT

Women suffering of infectious-dependent bronchial asthma show at the second half of pregnancy a sharp reduction of the fibrinolytic potential that is manifested in a decrease of plasminogen activator and urokinase activity of the urine, in an elevation of the antiactivator and antiplasmin activity, growth of the concentration of alpha2-macroglobulins. At the same time high levels of fibrinogen are noted and low levels of fibrin degradation.


Subject(s)
Asthma/blood , Fibrinolysis , Pregnancy Complications/blood , Adolescent , Adult , Asthma/urine , Blood Proteins/analysis , Female , Humans , Pregnancy , Pregnancy Complications/urine , Pregnancy Trimester, Third , Urokinase-Type Plasminogen Activator/urine
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