Ba–Sr and Ni–Co Solid-State Interdiffusion in the Hexagonal Ferrites Ba2M2Fe12O22and Sr2M2Fe12O22(M = Ni2+, Co2+)

The Ni, Co, Ba, and Sr profiles in the diffusion zones produced between hexagonal Y-ferrites (Ba₂Co₂Fe₁₂O₂₂–Ba₂Ni₂Fe₁₂O₂₂, Sr₂Ni₂Fe₁₂O₂₂–Sr₂Co₂Fe₁₂O₂₂, Sr₂Co₂Fe₁₂O₂₂–Ba₂Co₂Fe₁₂O₂₂, Sr₂Ni₂Fe₁₂O₂₂–Ba₂Ni₂Fe₁₂O₂₂, Ba₂Co₂Fe₁₂O₂₂–Sr₂Ni₂Fe₁₂O₂₂, and Sr₂Co₂Fe₁₂O₂₂–Ba₂Ni₂Fe₁₂O₂₂) by annealing at 1470 K were used to evaluate the interdiffusion coefficients of the cations involved by the Boltzmann–Matano method over the whole composition range.     

Effect of Cardiotonic Steroid Marinobufagenin on Vascular Remodeling and Cognitive Impairment in Young Dahl-S Rats

The hypertensive response in Dahl salt-sensitive (DSS) rats on a high-salt (HS) diet is accompanied by central arterial stiffening (CAS), a risk factor for dementia, and heightened levels of a prohypertensive and profibrotic factor, the endogenous Na/K-ATPase inhibitor marinobufagenin (MBG). We studied the effect of the in vivo administration of MBG or HS diet on blood pressure (BP), CAS, and behavioral function in young DSS rats and normotensive Sprague–Dawley rats (SD), the genetic background for DSS rats. Eight-week-old male SD and DSS rats were given an HS diet (8% NaCl, n = 18/group) or a low-salt diet (LS; 0.1% NaCl, n = 14–18/group) for 8 weeks or MBG (50 µg/kg/day, n = 15–18/group) administered via osmotic minipumps for 4 weeks in the presence of the LS diet. The MBG-treated groups received the LS diet. The systolic BP (SBP); the aortic pulse wave velocity (aPWV), a marker of CAS; MBG levels; spatial memory, measured by a water maze task; and tissue collection for the histochemical analysis were assessed at the end of the experiment. DSS-LS rats had higher SBP, higher aPWV, and poorer spatial memory than SD-LS rats. The administration of stressors HS and MBG increased aPWV, SBP, and aortic wall collagen abundance in both strains vs. their LS controls. In SD rats, HS or MBG administration did not affect heart parameters, as assessed by ECHO vs. the SD-LS control. In DSS rats, impaired whole-heart structure and function were observed after HS diet administration in DSS-HS vs. DSS-LS rats. MBG treatment did not affect the ECHO parameters in DSS-MBG vs. DSS-LS rats. The HS diet led to an increase in endogenous plasma and urine MBG levels in both SD and DSS groups. Thus, the prohypertensive and profibrotic effect of HS diet might be partially attributed to an increase in MBG. The prohypertensive and profibrotic functions of MBG were pronounced in both DSS and SD rats, although quantitative PCR revealed that different profiles of profibrotic genes in DSS and SD rats was activated after MBG or HS administration. Spatial memory was not affected by HS diet or MBG treatment in either SD or DSS rats. Impaired cognitive function was associated with higher BP, CAS, and cardiovascular remodeling in young DSS-LS rats, as compared to young SD-LS rats. MBG and HS had similar effects on the cardiovascular system and its function in DSS and SD rats, although the rate of change in SD rats was lower than in DSS rats. The absence of a cumulative effect of increased aPWV and BP on spatial memory can be explained by the cerebrovascular and brain plasticity in young rats, which help the animals to tolerate CAS elevated by HS and MBG and to counterbalance the profibrotic effect of heightened MBG.     

Diffusion welding of 12Cr18Ni10Ti steel to palladium alloy foil

The special features of the method of diffusion welding of corrosion-resisting steel with a palladium foil using an intermediate layer made of nickel are presented. The method can be used for producing full-strength and vacuum-tight welded joints.     

Clinoptilolite/Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>: a magnetic sorbent for removing <Superscript>90</Superscript>Sr from aqueous media

The ability of a magnetic sorbent prepared by modification of clinoptilolite with magnetite to take up ⁹⁰Sr was studied. ⁹⁰Sr is sorbed most efficiently at pH in the range 6–9. At the sorbent dosage of 5 g dm^–3 and sorption time of 24 h, the degree of ⁹⁰Sr sorption from aqueous solution is as high as 99.8%.     

Comprehensive study of the geometry, surface area, membrane reserve potential, and osmoregulation of blood leukocytes

Comprehensive method for examining the morphology and function of leukocytes is based on the comparison of the size and count of cells before and after incubation of different duration in media with low osmolarity. The method helps assess the leukocyte geometry, the reserve potential of the cytoplasmatic and nuclear membranes, the regulatory features and osmotic stability of cells.