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Techniques are described that make it possible to measure the X-ray transport velocity in closed cavities, the time of radiation heating of foils, the radiation temperature, and the timing parameters of X-ray pulses in experiments at the ISKRA-5 facility. The methods are based on position-sensitive time-resolving (with a spatial resolution of 150 µm and a time resolution of 50 ps) measurements of X-rays in four narrow spectral regions of 0.2–1.0 keV using X-ray streak cameras, as well as on multiframe recording (with a frame duration of 100 ps, ​​a frame number of 10, and a spatial resolution of 30 µm). In the experiments the peak Planck temperature of the radiation was 110–150 eV in the irradiating target and 50–90 eV in the additional box and behind the foils; the X-ray transport velocity in closed cavities ranged from 0.5 to 13 mm/ns and the time of thermal breakdown of foils was in range of 50–550 ps. [ABSTRACT FROM AUTHOR]

A detailed structural, magnetic, and ferroelectric property of bulk polycrystalline Y1-xZrxCrO3 (0 ≤ x ≤ 0.2) has been made. All the samples in the present series were made using the standard solid-state sintering technique. X-ray diffraction (XRD) data reveals that the single-phase samples can be prepared for Zr-concentration up to x = 0.1, and a systematic decrease of the lattice parameters can be observed with the increase of Zr doping at the Y-site in the present YCrO3 system. All the samples show paramagnetic to antiferromagnetic transition around 140 K (TN) as revealed from the temperature-dependent magnetization (M) data, and a small increase in the value of saturation magnetization (Msat) can be seen with successive Zr-doping in the system. Interestingly, unlike YCrO3, the M-T data measured under the zero-field cooled (ZFC) condition shows negative M value for both the Zr-doped samples in the present series below TN. A notable enhancement of both critical field (HC) and remnant magnetization (Mr) is observed for the Zr-doped samples compared with the pristine YCrO3 sample measured under similar conditions. Polarization-electric field (P-E) hysteresis behavior of undoped and Zr-doped samples is measured at low temperature to reduce leakage current contribution, show an enhancement of remnant polarization (Pr) with successive Zr doping within YCrO3, indicating a better bifferoic nature in Zr-doped sample in the present study. [ABSTRACT FROM AUTHOR]

Purpose: The relationship between posterior shoulder instability and increased glenoid retroversion has been documented. Posterior open wedge glenoid osteotomy is a possible treatment option for patients with increased glenoid retroversion, but outcomes in the literature are limited. Therefore, the purpose of this study was to report the clinical and radiological outcomes following posterior glenoid osteotomy.Methods: Patients that underwent posterior glenoid osteotomy for posterior shoulder instability with a GR angle of more than or equal to 10°, and were at least 12 months out from surgery, were included in the study. General data, medical history, and radiographic data such as the pre- and postoperative glenoid retroversion angle were extracted from the patients' hospital documentation notes. To evaluate the postoperative outcome, the Rowe standard rating scale for shoulder instability and the Oxford shoulder instability score were collected retrospectively.Results: A total of 12 shoulders (11 patients) could be included. The mean pre-operative glenoid retroversion was 23.3° (range 12°-35°) and this reduced significantly (p = 0.003) to a mean of 13° (range 1°-28°) postoperatively. At a mean follow-up of 19.8 months (range 14-36), the median Rowe score was 90 points (range 45-100 points) and the median Oxford instability score was 44 points (range 21-48 points). There were no postoperative re-dislocations or revision surgeries; however, one patient reported signs of recurrent shoulder instability and four asymptomatic glenoid neck fractures occurred.Conclusion: Open wedge posterior glenoid osteotomy provides reliable clinical results with a low rate of clinical failure in a stringently selected patient cohort at short-term follow-up. However, due to the risk of potentially severe complications, we advocate this procedure for experienced shoulder surgeons only, who are familiar with its anatomical and technical considerations.Level Of Evidence: IV (case series). [ABSTRACT FROM AUTHOR]

A precursor powder was obtained from drying the solutions of a mixture of different ratios of Cu, Zn and Sn chloride and thiourea. The CuZnSnS (CZTS) samples were prepared from thermal decomposition of the corresponding precursors in vacuum, and were then characterized using scanning emission microscopy, energy dispersive x-ray analysis, x-ray powder diffraction and Raman scattering. According to x-ray diffraction analysis, all the synthesized samples had a tetragonal structure of space group $$I\overline{4} 2m$$ . The electrical properties of the CZTS samples were investigated in the temperature range of 10-325 K. The charge carrier concentration was measured to be about p = 1 × 10 cm. A crossover from a nearest-neighbor hopping conduction mechanism at high temperatures ( T > 150 K) to a Mott variable-range hopping conduction mechanism at low temperatures ( T < 150 K) was observed. The activation energies of the CZTS samples were calculated for the low and high ranges of temperature. A thin film on quartz substrates was obtained using magnetron sputtering, for which a band gap of E = 1.3 eV was determined from transmittance measurements. [ABSTRACT FROM AUTHOR]

In the present investigation detailed structural, electrical, magnetic and thermoelectric measurements on bulk samples of Li-doped LaLiMnO (0.05 ≤ x ≤ 0.3) manganites have been done. The samples are synthesized by wet-chemical mixing route and XRD analysis using Rietveld refinement revealed single phase behaviour upto Li-concentration x = 0.25. All the samples in the present series show ferromagnetic behaviour while metallic behaviour is shown by the samples upto Li concentration x = 0.2. Beyond x = 0.2 the sample (i.e., LaLiMnO) show insulating behaviour for the entire temperature range accompanied by charge-order transition around T = 225 K. The low temperature resistivity data are best fitted by ρ(T) = ρ + ρT + C/sinh(hυ/2kT), where C is a constant. Such behaviour might be an indication of the small-polaron coherent motion which involves a relaxation due to a soft optical phonon mode that is strongly coupled to the carriers. Thermoelectric power (TEP) measurements reveal interesting results showing a colossal value of −340 μV/K around 25 K for the CO sample in the present series. The probable mechanism responsible for the observed large TEP has been discussed here. [ABSTRACT FROM AUTHOR]

The article presents the study of the biochemical and physiological properties of Gulosibacter species BS4 which uses Nylon-six and epsilon-caprolactam oligomers in producing carbon and energy sources.

The article presents a study that investigates the role of caprolactam catabolism chemical compounds in Pseudomonas strains.

Five bacterial strains with the unique ability to utilize low-molecular linear caprolactam oligomers (nylon oligomers) were isolated from soil samples contaminated with industrial wastes of epsilon-caprolactam. Based on the properties studied and also on the analysis of 16S rRNA gene nucleotide sequences, the strains BS2, BS3, BS9, BS38, and BS57 were identified as belonging to the genera Arthrobacter, Brevibacterium, Microbacterium, Gulosibacter, and Achromobacter, respectively. All of the strains also utilized 6-aminohexanoic and adipic acids, which are intermediates of the epsilon-caprolactam catabolism. This indirectly points to the fact that degradation of oligomers in these bacteria occurs via the monomer degradation pathway. The strains BS9 and BS57 utilized only caprolactam oligomers, while BS2, BS3, and BS38 also degraded epsilon-caprolactam and its homologs, enantolactam and caprylolactam, which differentiates the latter from the previously known oligomers-degrading bacteria and suggests the presence in these strains of enzymes with lactam hydrolase activity, in addition to 6-aminohexanoate-dimer hydrolase. [ABSTRACT FROM AUTHOR]

The amino acid residues essential for the enzymatic activity of bacteriophage T5 deoxyribonucleoside monophosphate kinase were determined using a computer model of the enzyme active site. By site-directed mutagenesis, cloning, and gene expression in E. coli, a series of proteins were obtained with single substitutions of the conserved active site amino acid residues—S13A, D16N, T17N, T17S, R130K, K131E, Q134A, G137A, T138A, W150F, W150A, D170N, R172I, and E176Q. After purification by ion exchange and affine chromatography electrophoretically homogeneous preparations were obtained. The study of the enzymatic activity with natural acceptors of the phosphoryl group (dAMP, dCMP, dGMP, and dTMP) demonstrated that the substitutions of charged amino acid residues of the NMP binding domain (R130, R172, D170, and E176) caused nearly complete loss of enzymatic properties. It was found that the presence of the OH-group at position 17 was also important for the catalytic activity. On the basis of the analysis of specific activity variations we assumed that arginine residues at positions 130 and 172 were involved in the binding to the donor γ-phosphoryl and acceptor α-phosphoryl groups, as well as the aspartic acid residue at position 16 of the ATP-binding site (P-loop), in the binding to some acceptors, first of all dTMP. Disproportional changes in enzymatic activities of partially active mutants, G137A, T138A, T17N, Q134A, S13A, and D16N, toward different substrates may indicate that different amino acid residues participate in the binding to various substrates. [ABSTRACT FROM AUTHOR]

Cladribine (2-chloro-2′-deoxyadenosine) was synthesized using intact cells of the recombinant Escherichia coli strain producing Geobacillus stearothermophilus B-2194 thermostable purine-nucleoside phosphorylase II (EC 2.4.2.1). Use of the cells containing this thermostable enzyme allowed the process to be conducted at a temperature of 70°C, which provided the maximal concentrations of sparingly soluble substrates. The best results were obtained with 2-chloroadenine as a modified base. The highest yield of the target 2-chloro-2′-deoxyadenosine (up to 95% in the case of deoxyguanosine) was reached when using 2′-deoxypurines as donors of deoxyribose. Use of thymidine for these purposes required its considerable molar excess over 2-chloroadenine (up to 6:1), which is connected with a nonoptimal amount of endogenous thymidine phosphorylase, necessary for synthesis of deoxyribose-1-phosphate, in the transglycosylation reaction. [ABSTRACT FROM AUTHOR]

Two techniques for recording the absolute yield of continuous X rays in the spectral range > 1 keV and M-series line X rays from flat Au targets irradiated with one channel of the Iskra-5 facility are described. In the first and second methods, radiation is detected with a KAP-crystal-based spectrograph and an X-ray streak camera with a 50-ps time resolution, respectively. Both techniques allow obtainment of absolute values of the yields of continuous and line X-ray radiations from laser plasma that coincide within the measurement accuracy. The time-dependent plasma electron temperature is measured with an X-ray streak camera. [ABSTRACT FROM AUTHOR]

Three 18-membered analogues of the N-terminal fragment of the sarcotoxin IA cationic antimicrobial peptide were synthesized by the solid phase method of peptide synthesis with the use of swellographic monitoring. The ability of these peptides to inhibit the growth of various bacteria in culture medium and their hemolytic activity in experiments on human erythrocytes were studied. The analogue completely corresponding to the N-terminal amino acid sequence of the natural sarcotoxin IA with the amide group on its C-terminus exhibited higher antibacterial activity. The presence of carboxyl group on the C-terminus or the substitution of Tyr for Trp2 resulted in a decrease in the antimicrobial activity of the peptide. Our results indicate that the amphiphilic N-terminal peptide corresponding to the 1–18 sequence of sarcotoxin IA involves the moieties responsible for the antimicrobial activity of the antibiotic. [ABSTRACT FROM AUTHOR]

It was demonstrated that, in the phenotypically colorless leaves of a sunflower ( Helianthus annuusL.) plastome mutant with a heavily reduced level of chlorophyll, all pigment–protein complexes of the photosynthetic apparatus typical for the wild type were present. However, the ratio between them was changed. During aging of the mutant leaves, pigment–protein complexes of photosystem I were destroyed first followed by those of photosystem II. Chlorophyll a/ b-containing light-harvesting complex II turned out to be the most stable. This conforms to an increased content of lutein and violaxanthin in mutant leaves. A synchrony of the decreases in the chlorophyll and 5-aminolevulinic acid (ALA) contents throughout all ontogenetic stages of the colorless mutant leaves made it possible to suggest that a decrease in the synthesis and resynthesis of chlorophyll during the formation and development of such leaves is caused by the inhibition of an initial stage of this process, namely, the biosynthesis of ALA molecules. The activity of the enzymes converting ALA into protochlorophyllide did not limit chlorophyll biosynthesis. Possible mechanisms controlling the synthesis of ALA destined for chlorophyll formation are discussed. [ABSTRACT FROM AUTHOR]

With the aim of investigating the relationship between chemical structure and biological activity we have synthesized and studied the effect of (2H-1,2,4-benzothiadiazine-1,1-dioxide-3-yl)methylamides of 1-R-4-hydroxy-2-oxoquinoline-3-carboxylic acids on kidney urinary output. [ABSTRACT FROM AUTHOR]

The biosynthesis of heme, a plant tetrapyrrole, was studied in the leaves of a chlorophyll-deficient plastome mutant of the sunflower ( Helianthus annuus L, line 2-24, albina form). In the light, the content of 5-aminolevulinic acid (ALA) in white mutant leaves was, on the average, ten times less than in that of the wild-type form (line 3629). Chlorophyll content in mutant leaves comprised only 0.3% of that of control plants. The activities of Fe-chelatase and ALA dehydratase in the heme synthesis were either comparable to or even higher than those in the wild-type leaves. A normal respiration rate in white mutant leaves, the equal content of phytochrome apoproteins in plants of both types, and the lack of noticeable morphogenetic differences realized through the phytochrome system can indicate that mutant and wild-type leaves are similar in their levels of phytochrome and the cytochromes of mitochondrial respiration. Nevertheless, in the mutant, the content of heme noncovalently bound by apoproteins amounted to only one third of its content in the wild-type plants. It seems that a dramatic decrease in the capability of white leaves for chlorophyll biosynthesis and for the formation of the photosynthetic apparatus is responsible for a low demand for chloroplast cytochromes, which is the major cause of a reduced heme content in the mutant. [ABSTRACT FROM AUTHOR]

A preparative method is proposed for obtaining N-substituted 1H-4-hydroxy-2-oxoquinoline-3-acetic acid amides. X-Ray diffraction analysis of one of the synthesized compounds has been carried out. The effect of the obtained substances on thyroid gland function has been studied. [ABSTRACT FROM AUTHOR]

Treatment of 1-R′-2-oxo-4-hydroxyquinolin-3-ylamides of α-halogen-substituted carboxylic acids with sodium methoxide leads to the formation of 2-R-3-oxomorpholino-[5,6-c]-6-R′-quinolin-5-ones. The antituberculosis activity of the compounds synthesized was studied. [ABSTRACT FROM AUTHOR]

Ethyl esters of 1-R-2-oxo-4-hydroxyquinoline-3-carboxylic acids under thermolysis conditions are converted to 5,9-di-R-6,7,8-trioxodiquinolino[3,4-b;3′,4′-e]-4H-pyrans. One of the synthesized compounds was studied by X-ray diffraction. [ABSTRACT FROM AUTHOR]

An improved method for the synthesis of anilides of 1H-2-oxo-4-hydroxyquinoline-3-carboxylic acid was proposed. Results of the study of antithyroid and anti-tuberculosis activity of the compounds synthesized are presented. [ABSTRACT FROM AUTHOR]

S-(−)-1-phenylethylamide of 6-bromo-4-hydroxy-1-isoamyl-2-oxo-3-quinolinecarboxylic acid was synthesized. X-ray diffraction investigation of this product was carried out to determine its absolute configuration. [ABSTRACT FROM AUTHOR]

A synthesis is reported for optically pure antipodes of 1-phenylethylamides of 1-R-4-hydroxy-2-oxo-3-quinolinecarboxylic acids. An attempt was made to establish the absolute configuration of these products by X-ray diffraction crystallographic analysis. The anticonvulsant activity of the S-enantiomers was studied. [ABSTRACT FROM AUTHOR]

We consider different variants for synthesis of 2-R-oxazolo[4,5-c]quinolin-4(5H)-ones based on 3-amino-1H-2-oxo-4-hydroxyquinolines and their 3-N-acyl derivatives. We show, that in the latter case, formation of the oxazole ring is possible via two routes, depending on the nature of the substituent on the acyl residue. [ABSTRACT FROM AUTHOR]

The methyl ester of 1H-2-oxo-4-hydroxyquinoline-3-acetic acid is condensed in pyridine with salicylaldehydes to 1H-2-oxo-3-(coumarin-3-yl)-4-hydroxyquinolines. We present the results of a study of the effect of the synthesized compounds on thyroid function. [ABSTRACT FROM AUTHOR]

3-Amino-2-oxo-4-hydroxyquinolines when exposed to light are quantitatively converted to di(1R-2-oxo-4-hydroxyquinolin-3-yl)amines. We have carried out an x-ray diffraction study of one such compound. [ABSTRACT FROM AUTHOR]

We propose a novel method for obtaining the methyl ester of 1H-2-oxo-4-hydroxyquinoline-3-acetic acid. [ABSTRACT FROM AUTHOR]

We propose preparative synthesis methods for 2-thio-4-hydroxy-, 2-oxo-4-mercapto-, and 2-thio-4-mercapto-1H-3-(2-benzimidazolyl)quinolines. We have studied the antithyroid activity of the synthesized compounds. [ABSTRACT FROM AUTHOR]

Different methods of synthesizing esters of 1H-2-oxo-4-hydroxy-3-quinolineacetic acid were studied. Results are given for tests of the anti-inflammatory activity of these products. [ABSTRACT FROM AUTHOR]

3-Amino-1-R-2-oxo-4-hydroxyquinolines easily undergo acid hydrolysis with formation of the corresponding 1-R-2-oxo-3,4-dihydroxyquinolines. [ABSTRACT FROM AUTHOR]

Neutron powder diffraction experiments to refine the crystal and magnetic structures of a La0.7Ca0.3Mn0.5Fe0.5O3 compound were carried out at temperatures of 10, 50, 80, 100, 120, 150, 200, 250 and 300 K. The obtained results support the conclusion that there is no long-range ferromagnetic order at all these temperatures. Structural parameters and, especially, the magnetic moments are calculated as a function of temperature. Their polynomial extrapolation is performed. Magnetization and electrical resistivity measurements were also performed in the temperature range of 5-300 K in magnetic fields up to 1 T. Field magnetization is measured to confirm the formation of the spin-glass-like state. These experimental results indicate formation of a complex magnetic state in which the long-range antiferromagnetic G-type phase coexists with short-range ferromagnetic clusters. Electrical conductivity of La0.7Ca0.3Mn0.5Fe0.5O3 demonstrates an anomalous temperature behavior suggesting a switching between different states. Correlation between the critical temperatures of magnetic and electrical transitions is demonstrated. Resistivity data in various theoretical models are processed. We discuss the origin of the unconventional magnetic state, the mechanisms of the electrical conductivity, and the correlation between magnetic and transport properties in this manganite. [ABSTRACT FROM AUTHOR]