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A new superconductor BaAg1.8Bi2 with a previously unknown variant of the monoclinically distorted CaBe2Ge2 structure (space group C2/m) has been crystallized in the form of single crystals from a bismuth flux. The temperature and magnetic field dependences of the magnetic susceptibility and resistance have shown that this compound transits to a superconducting state at the temperature Tc = 5.4 K. According to the found Ginzburg–Landau parameter κ = 27, this compound is a type-II superconductor with the first and second critical fields Hc1(0) = 53 Oe and Hc2(0) = 2.1 × 104 Oe and the critical current density reaching 4.4 kA/cm2 at 2.5 K. It can be assumed that, similar to some superconducting 112 type bismuthides, superconductivity in this compound is due to the planar square bismuth sublattice contained in the fluorite-like [BiAg0.8] layer rather than to the [AgBi] layers where Ag atoms are locally disordered. This could explain the unusually high Tc value for bismuthides belonging to the CaBe2Ge2 structural type and its derivatives. [ABSTRACT FROM AUTHOR]

Various bone and joint pathology is quite common among companion animals, a significant risk factor for which is considered to be a violation of bone metabolism. The aim of the work is to determine radiological and pathochemical criteria in the dynamics of osteoporosis process in the model of rabbits. The experimental (n = 18) and control (n = 9) groups of animals were formed. Experimental osteoporosis in rabbits of the experimental group was caused by the administration of 0.4% solution of dexamethasone (4 mg / ml) (KRKA, Slovenia) for the 21st day at a dose of 1.2 mg / kg body weight 1 time / day. Control animals were injected with saline. Blood samples for biochemical studies were taken before the induction of osteoporosis and on the 7th, 14th, 21st day. Serum levels of total calcium (Ca) and phosphorus, activity of total alkaline phosphatase and its bone isoenzyme, tartrate-resistant acid phosphatase were determined. Measurements were performed with a spectrophotometer Stat Fax 4500. X-ray examinations were performed on an X-ray machine RUM-20 before the induction of osteoporosis and on the 7th, 14th, 21st day of the study. On the 14th day of the study, some areas of the spongy substance of the proximal femur have the appearance of a large-loop pattern due to the resorption of individual bone beams. There is also an expansion of the bone marrow canal due to bone resorption, thinning and emphasizing the edges of the cortical layer. On the 21st day, changes characteristic of osteoporosis were observed - low intensity of X-ray contrast shadow of bone, significant thinning of bone structure. Radiographically established changes in bone tissue correlate with biochemical parameters of rabbit blood. On the 21st day of osteoporosis induction in experimental animals, the level of total Ca decreased 2.1 times (p

Metal structures for osteosynthesis available in veterinary orthopedics are not able to compensate for the lost elements of bone tissue in complex splinter fractures. It is prompt the use of hydroxyappatite materials that replaced bone defects for maintenance of osteoconductive function, and ideally would combine osteointegration and osteoinductive properties. However, their influence on the biological processes of fracture consolidation which go through a number of successive stages and end with the formation of bone tissue in the fracture zone identical to the maternal, is insufficiently substantiated according to the criteria of the molecular biological phase of reparative osteogenesis. The aim of the study was to investigate the dynamics of biochemical osteotropic parameters and the level of NO using silicon-doped ceramics for fractures heeling in dogs. Materials and methods. The animals suffering of fractures that were admitted to the faculty clinic were divided into control (n=7) and experimental (n=7) groups. In both groups, extracortical osteosynthesis was performed with a support plate from an unalloyed titanium alloy. In the control group, bone defects were left to heal under spontaneous blood clot, and in the experimental group, they were replaced with ceramic based on hydroxyapatite with β-tricalciumphosphate doped with silicon (HA/β-TCP/l-Si–3).Blood samples were taken after the injury no later than the 48th day, and on the 3th, 12th, 21th, 42th and 60th days after osteosynthesis. To increase the objectivity of the biochemical analysis, we additionally formed a group of clinically healthy dogs that were admitted to the clinic for routine vaccination (n=10). It included the spectrophotometric determination of the content of NO, BALP, TRACP, Ca, P, Mg, total protein in blood serum, and fibrinogen in blood plasma. Research results. A clinical study showed that in the case of using HA/β-TCP/l-Si–3for splinter fractures, the stages of reparative osteogenesis are more optimized in time, and their consolidation occurs on average 19 days earlier than in the control group. The results of the biochemical study showed that when using HA/β-TCP/l-Si–3, it is accompanied by a peak NO value already on the third day, which is significantly higher than in the control group and indicates early angiogenesis in the research group. In terms of TRACP, the period of osteoresorption in the control group was permanent with little expressed peaks of activity. However, in the research group, the peak of TRACP activity is limited to 12 and 21 days, which is evidence of an optimized inflammatoryresorptive phase. In parallel with this, the activity of BALP increases, which indicates the consistency of the stages of reparative osteogenesis and provides an optimized and accelerated consolidation of fractures in the research group. Conclusion. The dynamics of NO, BALP and TRACP pathochemically substantiates the optimized reparative osteogenesis when using HA/β-TCP/l-Si–3 for bone defects replacement in cases of splinter fractures of tubular bones.

Studies of the water-physical, physical-chemical and biological properties of meadow-chernozem soils were carried out on a rice irrigation system located in the present-day delta of the Kuban River. Rice meadow-chernozem soils have good water and general physical properties of humus layers. An increase in compaction is observed in the lower horizons of these soils. Meadow-chernozem soils are distinguished by low content of organic matter in arable horizons (3,2-3,4 %), neutral reaction of soil solution (рН 6,8-6,9) and high indices of cation exchange capacity (38,7-39,1 mmol/100g). The mycological composition of the studied soils in the autumn-spring periods was identified and identified. The soil was more saturated with representatives of the suppressive group at the beginning of rice vegetation, the opportunistic group was not detected and the antiphytopathogenic potential was 1:2. The spring-fed rice crop rotations soils are prone to soil stresses that are oversaturated with suppressors. In autumn, the ratio of conditionally suppressive to saprotrophic and pathogenic mycota was 1.5:4.5:7. The growth of colonies of the micromycete genus Trichoderma is traced, which confirms the beginning of a long process and the slow recovery of soil degradation processes.

A number of new copper(II) complexes of 2-(N-tosylamino)benzaldehyde benzoylhydrazone (H2L) CuLLn (n = 1–6) with heterocyclic donor ligands (L1 = 1-propyl-2-aminobenzimidazole, L2 = 1‑hexyl-2-aminobenzimidazole, L3 = 1-octyl-2-aminobenzimidazole, L4 = 2,2'-bipyridine, L5 = 1,10-phenanthroline, and L6 = 2-aminopyridine) is synthesized. The structures and compositions of the synthesized compounds are determined by elemental analysis, 1Н NMR spectroscopy, IR spectroscopy, and magnetochemistry. The molecular structures of complexes CuLL1,2,4−6 are determined by XRD (CIF files CCDC nos. 2341480 (CuLL1), 2341468 (CuLL2), 2341478 (CuLL4), 2341477 (CuLL5), and 2341479 (CuLL6)). The biological activity of the complexes is studied. The adducts with L1, L2, and L6 exhibit a significantly higher anti-protist activity than chloroquine used as the reference compound. [ABSTRACT FROM AUTHOR]