Tunka-133: Results of 3 year operation Prosin, V.V.; Berezhnev, S.F.; Budnev, N.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2014, Letnik:
756
Journal Article
Recenzirano
Odprti dostop
The EAS Cherenkov light array Tunka-133, with ~3km2 geometric area, is taking data since 2009. The array permits a detailed study of cosmic ray energy spectrum and mass composition in the PeV energy ...range. After a short description of the methods of EAS parameter reconstruction, we present the all-particle energy spectrum and results of studying CR composition, based on 3 seasons of array operation. In the last part of the paper, we discuss possible interpretations of the obtained results.
Ziziphora clinopodioides subsp. bungeana (Juz.) Rech.f. is a subshrub that is widely distributed in China, Kazakhstan, Kyrgyzstan, Mongolia, Russia, Tajikistan, Turkmenistan, and Uzbekistan. The ...species is used in traditional medicine for the relief of symptoms connected to cardiovascular diseases like coronary heart disease or hypertension.
was to validate traditional use of Z. clinopodioides subsp. bungeana for the treatment of coronary hearth diseases using in vivo models and to find active compounds responsible for the activity.
Multiple extracts were obtained from the aerial parts of Z. clinopodioides subsp. bungeana using maceration, liquid-liquid extraction, CO2 extraction and ultrasound-assisted extraction. Preliminary screening studies for the evaluation of the efficacy of Z. clinopodioides subsp. bungeana extracts on the model of hemic hypoxia were performed. The most effective samples were selected and included in the main study. Stage 2 of the study evaluated the cardiotropic activity of the selected extracts on a model of chronic heart failure. Preparations were administered to animals intragastrically once a day for 28 days. For the isolation of individual compounds plant material was extracted with 96% ethanol. The obtained crude extract was sequentially extracted with n-hexane and dichloromethane and separated by chromatography on a Diaion HP-20 column. The obtained fractions were further subjected to Sephadex LH-20 column chromatography and eluted isocratically with 96% ethanol (EtOH) to yield subfractions, which were further separated by preparative HPLC to obtain 13 individual compounds.
Extracts obtained from Ziziphora clinopodioides subsp. bungeana (Juz.) Rech.f. herb were subjected to pharmacological screening for the evaluation of their efficacy on hemic hypoxia. Based on the obtained results, out of the sixteen tested extracts two (AR and US 60%) were selected for further evaluation of their cardiotropic activity. Modeling of chronic heart failure was carried out in accordance with the following stages: 1) anesthesia with chloral hydrate at a dose of 450 mg/kg, intraperitoneally, 2) artificial ventilation of the lungs, 3) thoracotomy, 4) modeling of permanent ischemic or ischemic-reperfusion damage. Both extracts effected the indicators of contraction and output, comparable to the reference drug - Monopril. Based on the extraction methods used to obtain RAF and US60 and data from the literature, it can be assumed that they contain compounds with medium polarity, including polyphenols and terpenoids. At the next stage three previously undescribed monoterpenoid derivatives – Ziziphoric acid (1), Ziziphoroside D (2) and 6′-malonylziziphoroside A (3), along with two previously described megastigmane glucosides – blumenol C glucoside (4), blumenol C 9-O-(6′-O-malonyl-beta-D-glucopyranoside (5) and two previously described monoterpenoids 7a-hydroxymintlactone (6), 7-hydroxypiperitone (7) together with six polyphenols – pinocembrine-7-O-rutinoside (8), chrysine-7-O-rutinoside (9), acacetin-7-O-rutinoside (10), luteolin-7-O-rutinoside (11), rutin (12) and rosmarinic acid (13) were isolated from Z. clinopodioides subsp. bungeana extracts.
Our results support the traditional use of Z. clinopodioides subsp. bungeana for the treatment of coronary diseases. As a result of Z. clinopodioides subsp. bungeana extracts screening in vivo, two extracts were selected as potential cardiotropic agents. Phytochemical analysis of the plant material led to the isolation of five terpenoid derivatives, two megastigmane glycosides, five flavonoids and one cinnamic acid derivative, which could be responsible for the reported biological activity. Future experiments are required to understand the mechanisms of action for the isolated compounds.
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•The traditional use of Z. clinopodioides subsp. bungeana for treatment of coronary diseases was supported experimentally.•Extracts effected the indicators of contraction and output, comparable to the reference drug.•Three new monoterpenoid derivatives – Ziziphoric acid, Ziziphoroside D and 6′-malonylziziphoroside were isolated.
The new neutron-deficient isotope
249
No was synthesized for the first time in the fusion-evaporation reaction
204
Pb(
48
Ca,3n)
249
No. After separation, using the kinematic separator SHELS, the new ...isotope was identified with the GABRIELA detection system through genetic correlations with the known daughter and granddaughter nuclei
245
Fm and
241
Cf. The alpha-decay activity of
249
No has an energy of 9129(22) keV and half-life 38.3(2.8) ms. An upper limit of 0.2% was measured for the fission branch of
249
No. Based on the present data and recent information on the decay properties of
253
Rf and aided by Geant4 simulations, the ground state of
249
No is assigned the 5/2
+
622 neutron configuration and a partial decay scheme from
253
Rf to
245
Fm could be established. The production cross-section was found to be
σ
(3n)=0.47(4) nb at a mid-target beam energy of 225.4 MeV, which corresponds to the maximum of the calculated excitation function. Correlations of the
249
No alpha activity with subsequent alpha decays of energy 7728(20) keV and half-life
1
.
2
-
0.4
+
1.0
min provided a firm measurement of the electron-capture or
β
+
branch of
245
Fm to
245
Es. The excitation function for the 1n, 2n and 3n evaporation channels was measured. In the case of the 2n-evaporation channel
250
No, a strong variation of the ground state and isomeric state populations as a function of bombarding energy could be evidenced.
This article describes a digital method for an adaptive motion control of single-degree-of-freedom object according to a given movement function on condition that external low-frequency mechanical ...load can be changed arbitrarily. It is proposed to simulate an external load acting on a controlled object to predict its dynamic behavior. The external load model is determined by a set of coefficients that represent the partial derivatives of the load as a function of time and spatial coordinate. These coefficients are calculated using feedback data obtained at previous moments of the movement of the controlled object. The maximum order of derivatives in a model is called the model order. The structures of zero-, first-, and second-order models are given, including the practically important case of digital measurements of the angle of rotation of the steered shaft. The article also discusses the main practical problems associated with the calculation of model coefficients and their subsequent use to control the facility.
The Tunka-133 EAS Cherenkov light array: Status of 2011 Berezhnev, S.F.; Besson, D.; Budnev, N.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2012, Letnik:
692
Journal Article
Recenzirano
Odprti dostop
A new EAS Cherenkov light array, Tunka-133, with ∼1km2 geometrical area has been installed at the Tunka Valley (50km from Lake Baikal) in 2009. The array permits a detailed study of cosmic ray energy ...spectrum and mass composition in the energy range 1016–1018eV with a uniform method. We describe the array construction, DAQ and methods of the array calibration. The method of energy reconstruction and absolute calibration of measurements are discussed. The analysis of spatial and time structure of EAS Cherenkov light allows to estimate the depth of the EAS maximum Xmax.
The results on the all particles energy spectrum and the mean depth of the EAS maximum Xmax vs. primary energy derived from the data of two winter seasons (2009–2011) are presented. Preliminary results of joint operation of the Cherenkov array with antennas for the detection of EAS radio signals are shown. Plans for future upgrades – deployment of remote clusters, radioantennas and a scintillator detector network and a prototype of the HiSCORE gamma-telescope – are discussed.
Despite the efforts of the global medical and scientific community, tuberculosis remains the leading cause of death from infectious diseases. The expectation of success associated with the ...development of new anti-TB drugs was not justified, and the attention of researchers was largely drawn to the creation of new mycobacterial strains for vaccination against tuberculosis. The proposed review contains current information on the existing vaccine strains and the development of new, genetically engineered strains for the prevention of tuberculosis and the prevention and treatment of other diseases. The review includes relevant information on the correlation between BCG vaccination and the frequency and severity of COVID-19 infection.
Multiple-day distraction regenerate contains a number of foci or zones merging into one another with different structural organization of the fibrocellular basis that reflects successive stages of ...reparative regeneration. At the moment of the last traction, the central part of the regenerate represents a zone of fibrogenesis (growth zone), which is common for the proximal and distal parts of the distraction regenerate. The other zones are paired and symmetrical: zones of angiogenesis, fibrous osteogenesis (primary), and osteogenesis (secondary). The latter include subzones of resorption, secondary osteogenesis, and functional remodeling.
The mass, energy and angular distributions of binary fragments formed in the reactions
64
Ni +
238
U,
58
Fe +
244
Pu,
52
Cr +
248
Cm,
54
Cr +
248
Cm at energies near the Coulomb barrier have been ...measured. The analysis of energy distributions of the symmetric fragments with mass numbers
formed in these reactions have been applied to separate compound nucleus fission and quasi-fission. The estimated fusion probability for the reactions Cr, Fe, and Ni ions with actinide targets shows an exponential dependence on the mean fissility parameter of the system and shows also that reaction with Cr ions is more favorable for production of the super heavy element with
Z
= 120.
The mass-energy distributions of fragments formed in reactions
16,18
O +
232
Th,
238
U, and
22
Ne +
232
Th,
238
U at energies near the Coulomb barrier are measured to study the role of multimodal ...fission in the reactions of light ions with strongly deformed actinide nuclei. It is found that at these energies, multimodal fission affects significantly the mass–energy and angular distributions of fragments that results in an increase of the width of mass distributions and large angular anisotropy as in the case of quasifission.
An adaptive method of control of a system with single degree of freedom along a given trajectory of displacement under the conditions of unpredictable variation of a surmountable external load is set ...forth. Simulation of the load with the use of a special force vector that reflects the nature of its variation is proposed. The components of the force vector (averaged values of partial derivatives of the load with respect to time and spatial coordinate) are calculated from the working information which the control system receives at previous moments of displacement of the control object. The order of the model is the maximumorder of the derivatives included in the model. The general structure and derivation of formulas for models of zero, first and second order are given. The practical case of measurement of the angular displacement of a shaft using incremental encoders is given separately. Initially, direct load models are considered in which time is the independent variable. Then, for a drive with incremental encoders, inverse models are presented separately in which the angle of rotation of the output shaft is the independent coordinate. Conditions under which the adequacy of the parameters of the power vector and the redundancy and insufficiency of the order of the control model is estimated are considered separately. Based on these conditions, a general algorithm for the functioning of the control system by means of which both the parameters and the structure of the control system may be dynamically changed is given.
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