55 research outputs found
Peierls Instabilities in Quasi-One-Dimensional Quantum Double-Well Chains
Peierls-type instabilities in quarter-filled () and half-filled
() quantum double-well hydrogen-bonded chain are investigated
analytically in the framework of two-stage orientational-tunnelling model with
additional inclusion of the interactions of protons with two different optical
phonon branches. It is shown that when the energy of proton-phonon coupling
becomes large, the system undergoes a transition to a various types of
insulator states. The influence of two different transport amplitudes on ground
states properties is studied. The results are compared with the pressure effect
experimental investigations in superprotonic systems and hydrogen halides at
low temperatures.Comment: 7 pages, RevTeX, 9 eps figure
Complex 99mTc-PDA-DTPA for myocardial imaging
The 123I-labeled fatty acids such as 123I-Iodophenylpentadecanoic acid and 123I-Beta-methyliodophenylpentadecanoic acid are the agents used clinically for myocardial imaging. Fatty acids are the major source of energy for the normal myocardium. However, under ischemic conditions the myocardial cells switch to glucose metabolism for their energy needs. Fatty acids undergo prolonged metabolic stunning in patients with reversible ischemia, thereby helping in early diagnosis of coronary artery disease in highrisk patients. High cost andlimited availability of cyclotron-produced 123I, makes 99mTc-labeled fatty acids more desirable for the purpose. In diagnosis the dominant radionuclide is 99mTc. It is estimated that it is involved in about 85% of all imaging procedures in nuclear medicine. The method for preparation of new 99mTc-fatty chemical systems based on modified diethylene triamine pentaacetic acid (DTPA) molecule has been elaborated in this work . The main advantage using DTPA as chelate agent for radioactive label, is the molecule or it's derivative ability to form sufficiently stable complexes with different radioactive metals including technetium-99. Moiety of pentadecanoic acid addition gave the ability to prepare modified complex of DTPA. In a labeling procedure, freshly eluted Na99mTcO4 (20mCi) was added to a mixture of cysteine, stannous chloride, PDK-DTPA and ethanol in a vial. On keeping the reaction mixture at 90 0C for 30 min, [99mTc-PDK-DTPA] radiopharmaceutical was formed. Thereafter, the reaction mixture was cooled over ice and characterized by HPLC. The result of dynamic scintigraphic research showed, that after being injected, the substance is actively acumulated into myocardium. Eventually one can say that modified DTPA-moleculs are functionally suitable for myocardial imaging
Raise and characterization of a bread wheat hybrid line (Tulaykovskaya 10 × Saratovskaya 29) with chromosome 6Agi2 introgressed from Thinopyrum intermedium
Wheatgrass Thinopyrum intermedium is a source of agronomically valuable traits for common wheat. Partial wheat–wheatgrass amphidiploids and lines with wheatgrass chromosome substitutions are extensively used as intermediates in breeding programs. Line Agis 1 (6Agi2/6D) is present in the cultivar Tulaykovskaya 10 pedigree. Wheatgrass chromosome 6Agi2 carries multiple resistance to fungal diseases in various ecogeographical zones. In this work, we studied the transfer of chromosome 6Agi2 in hybrid populations Saratovskaya 29×Tulaykovskaya 10 (S29×T10) and Tulaykovskaya 10×Saratovskaya 29 (T10×S29). Chromosome 6Agi2 was identified by PCR with chromosome-specific primers and by genomic in situ hybridization (GISH). According to molecular data, 6Agi2 was transmitted to nearly half of the plants tested in the F2 and F3 generations. A new breeding line 49-14 (2n = 42) with chromosome pair 6Agi2 was isolated and characterized in T10×S29 F5 by GISH. According to the results of our field experiment in 2020, the line had high productivity traits. The grain weights per plant (10.04±0.93 g) and the number of grains per plant (259.36±22.49) did not differ significantly from the parent varieties. The number of grains per spikelet in the main spike was significantly higher than in S29 (p ≤ 0.001) or T10 (p ≤ 0.05). Plants were characterized by the ability to set 3.77±0.1 grains per spikelet, and this trait varied among individuals from 2.93 to 4.62. The grain protein content was 17.91 %, and the gluten content, 40.55 %. According to the screening for fungal disease resistance carried out in the field in 2018 and 2020, chromosome 6Agi2 makes plants retain immunity to the West Siberian population of brown rust and to dominant races of stem rust. It also provides medium resistant and medium susceptible types of response to yellow rust. The possibility of using lines/varieties of bread wheat with wheatgrass chromosomes 6Agi2 in breeding in order to increase protein content in the grain, to confer resistance to leaf diseases on plants and to create multiflowered forms is discussed
Strong-coupling approach for strongly correlated electron systems
A perturbation theory scheme in terms of electron hopping, which is based on
the Wick theorem for Hubbard operators, is developed. Diagrammatic series
contain single-site vertices connected by hopping lines and it is shown that
for each vertex the problem splits into the subspaces with ``vacuum states''
determined by the diagonal Hubbard operators and only excitations around these
vacuum states are allowed. The rules to construct diagrams are proposed. In the
limit of infinite spatial dimensions the total auxiliary single-site problem
exactly splits into subspaces that allows to build an analytical
thermodynamically consistent approach for a Hubbard model. Some analytical
results are given for the simple approximations when the two-pole
(alloy-analogy solution) and four-pole (Hartree-Fock approximation) structure
for Green's function is obtained. Two poles describe contribution from the
Fermi-liquid component, which is dominant for small electron and hole
concentrations (``overdoped case'' of high-'s), whereas other two describe
contribution from the non-Fermi liquid and are dominant close to half-filling
(``underdoped case'').Comment: 14 pages, revtex, feynmf, 5 EPS figures, two-column PRB style,
published in PR
The development of the model of a small-sized extractor with self-control interface level to divide a pair 99Мо/99mТс
The authors have proposed a construction of a model of a small-sized extractor with self-control interface level to separate 99mТс from molybdenum; the calculations for model have been carried out. The extractor construction makes it possible to carry out multiple cyclic extractions in a small enclosed volume. In a pilot model 99mТс yield into organic phase is more than 80 % at triple tandem cycle when the volume ratio of organic and water phases exceeds 1. Extractor small size predetermines the development of mobile extraction units and their application in medical centers
Preparation of a new nanocolloid radiopharmaceutical based on aluminum oxide
The authors have studied the regularities of 99mТс (VII) adsorption on activated gamma-oxide Al2O3. The paper demonstrates that oxide radionuclide sorption capacity depends on its acid treatment. The reduction process of 99mТс (VII) to 99mТс (IV) with bivalent tin Sn (II) was studied to determine its required and sufficient amount which could maintain full 99mТс "reducibliness" in the reaction mixture. The adsorption of 99mТс reduced on nanosized powder of aluminum gamma-oxide was investigated; and the technique for preparing 99mТс (IV)-Al2O3 nanocolloids was developed. The authors carried out the preliminary biomedical tests of 99mТс (IV)-Al2O3 compounds in animals to determine functional ability to radionuclide imaging of lymph glands
Complex 99mTc-PDA-DTPA for myocardial imaging
The 123I-labeled fatty acids such as 123I-Iodophenylpentadecanoic acid and 123I-Beta-methyliodophenylpentadecanoic acid are the agents used clinically for myocardial imaging. Fatty acids are the major source of energy for the normal myocardium. However, under ischemic conditions the myocardial cells switch to glucose metabolism for their energy needs. Fatty acids undergo prolonged metabolic stunning in patients with reversible ischemia, thereby helping in early diagnosis of coronary artery disease in highrisk patients. High cost andlimited availability of cyclotron-produced 123I, makes 99mTc-labeled fatty acids more desirable for the purpose. In diagnosis the dominant radionuclide is 99mTc. It is estimated that it is involved in about 85% of all imaging procedures in nuclear medicine. The method for preparation of new 99mTc-fatty chemical systems based on modified diethylene triamine pentaacetic acid (DTPA) molecule has been elaborated in this work . The main advantage using DTPA as chelate agent for radioactive label, is the molecule or it's derivative ability to form sufficiently stable complexes with different radioactive metals including technetium-99. Moiety of pentadecanoic acid addition gave the ability to prepare modified complex of DTPA. In a labeling procedure, freshly eluted Na99mTcO4 (20mCi) was added to a mixture of cysteine, stannous chloride, PDK-DTPA and ethanol in a vial. On keeping the reaction mixture at 90 0C for 30 min, [99mTc-PDK-DTPA] radiopharmaceutical was formed. Thereafter, the reaction mixture was cooled over ice and characterized by HPLC. The result of dynamic scintigraphic research showed, that after being injected, the substance is actively acumulated into myocardium. Eventually one can say that modified DTPA-moleculs are functionally suitable for myocardial imaging
SPECIFIC ANASTHESIOLOGICAL AND INTENSIVE CARE FOR CIVIL POPULATION IN MILITARY CONFLICTS (2ND REPORT)
There covered the characteristics of anesthetic management in trauma suffered by civilians during military conflicts (348 anaesthesis). Special attention is paid to organizational activities. A special focus is made on organizational aspects. It is demonstrated that the work optimization requires expediently the equipment of the shocking surgery of the medical admission unit and the operating rooms not only with the analgesia apparatus, but also with artificial pulmonary ventilation units, given that the essential method of anesthesia is the total intravenous anesthesia without anesthetic gas. The oxygen concentrators are advisable for the operating and intensive care units. It is necessary to know the presumable number of patients who can be attended simultaneously and to provide for the demanded quantity of medication and consumables. It is reasonable to have the kit assumed for one patient in the medical admission unit, where in most cases anesthesia as part of the complex intensive therapy is started
SPECIFIC ANASTHESIOLOGICAL AND INTENSIVE CARE FOR CIVIL POPULATION IN MILITARY CONFLICTS (1ST REPORT)
The article describes the emergency care in massive injury during the military conflict (230 patients, of them 220 are civilian population, of them 7 are children; 348 cases of urgent anesthesia). Special attention is paid to organizational activities. Specifics of peri-operative provisions, intensive care are defined and given special emphasis
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