An axisymmetric initial and boundary value problem regarding the impact of a liquid drop on a solid surface at constant speed is considered, for different contact angles. Mathematically, ...Navier–Stokes equations are used to describe the motion of each phase (liquid, air). A method of numerical solution is described, and sample calculations are presented.
To date, studies investigating the association between ACTN3 R577X and ACE I/D gene variants and elite sprint/power performance have been limited by small cohorts from mixed sport disciplines, ...without quantitative measures of performance.
To examine the association between these variants and sprint time in elite athletes.
We collected a total of 555 best personal 100-, 200-, and 400-m times of 346 elite sprinters in a large cohort of elite Caucasian or African origin sprinters from 10 different countries. Sprinters were genotyped for ACTN3 R577X and ACE ID variants.
On average, male Caucasian sprinters with the ACTN3 577RR or the ACE DD genotype had faster best 200-m sprint time than their 577XX (21.19 ± 0.53 s vs. 21.86 ± 0.54 s, p = 0.016) and ACE II (21.33 ± 0.56 vs. 21.93 ± 0.67 sec, p = 0.004) counterparts and only one case of ACE II, and no cases of ACTN3 577XX, had a faster 200-m time than the 2012 London Olympics qualifying (vs. 12 qualified sprinters with 577RR or 577RX genotype). Caucasian sprinters with the ACE DD genotype had faster best 400-m sprint time than their ACE II counterparts (46.94 ± 1.19 s vs. 48.50 ± 1.07 s, p = 0.003). Using genetic models we found that the ACTN3 577R allele and ACE D allele dominant model account for 0.92 % and 1.48 % of sprint time variance, respectively.
Despite sprint performance relying on many gene variants and environment, the % sprint time variance explained by ACE and ACTN3 is substantial at the elite level and might be the difference between a world record and only making the final.
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•Halloysite nanotubes induce up to a 30-fold increase of viscosity of semi-dilute solution of wormlike surfactant micelles.•The higher the charge of the nanotubes the higher their ...effect on the viscosity of oppositely charged wormlike micelles solution.•System has peculiar flow curves with two separate shear thinning regions and a plateau between them.
Soft viscoelastic nanocomposites based on entangled linear wormlike micelles of cationic surfactant erucyl bis(hydroxyethyl)methylammonium chloride and aluminosilicate clay halloysite nanotubes with a surface charge triggered by pH were prepared and studied by rheometry, ξ-potential measurements, thermogravimetric analysis, and cryo-TEM. It was shown that the nanotubes induce an increase of viscosity, which can be attributed to their incorporation into the network of entangled wormlike surfactant micelles via the attachment of micellar endcaps to the surfactant double layer on the surface of the nanotubes. The junctions between the micelles and the nanotubes were visualized by cryo-TEM. The soft nanocomposites demonstrate peculiar flow curves with two shear thinning regions and a plateau between them. The two slopes were attributed to the orientation of the nanotubes (at lower shear rates) and then of the micellar worms (at higher shear rates) along the direction of flow. The intermediate viscosity plateau may represent a stable flow when all nanotubes are oriented, while the micellar worms are not. The nanocomposite system was shown to be pH responsive. Its viscosity increases by 30 times with increasing pH from 4 to 9, which was explained by increasing surface charge of the nanotubes favoring the interaction with oppositely charged WLMs. Such soft materials with easily triggered rheological properties are very promising for various applications.
There is an important task of current medicine to identify mechanisms and new markers of subclinical atherosclerosis in order to develop early targets for the diagnosis and treatment of this disease, ...since it causes such widespread diseases as myocardial infarction, stroke, sudden death, and other common reasons of disability and mortality in developed countries. In recent years, studies of the human microbiome in different fields of medicine have become increasingly popular; there is evidence from numerous studies of the significant contribution of microbiome in different steps of atherogenesis. This review attempted to determine the current status of the databases PubMed and Scopus (until May, 2020) to highlight current ideas on the potential role of microbiome and its metabolites in atherosclerosis development, its mechanisms of action in lipids metabolism, endothelial dysfunction, inflammatory pathways, and mitochondrial dysfunction. Results of clinical studies elucidating the relationship of microbiome with subclinical atherosclerosis and cardiovascular disease considered in this article demonstrate strong association of microbiome composition and its metabolites with atherosclerosis and cardiovascular disease. Data on microbiome impact in atherogenesis open a wide perspective to develop new diagnostic and therapeutic approaches, but further comprehensive studies are necessary.
We report cathodic deposition of birnessite oxide from permanganate alkaline solutions into porous flexible cloth consisting from carbon nanotubes. Oxide distribution in the pores is studied by means ...of electron microscopy, including transmission microscopy of microtom cross-sections and local elemental analysis. Oxide distribution depends on applied deposition mode. The intermittent potentiostatic mode favors the penetration of permanganate reagent into the pores of CNT cloth and allows us to fabricate more homogeneous hybrid material. We demonstrate a number of advantages of hybrid materials with oxide located mostly inside the cloth pores as compared to oxide located at external surface of the cloth.
Experimental results of studies on ability to treat by laser beam holes into needles by 0.15-1.0 mm diameter made of steel are presented. Operating conditions such as radiant energy, pulse duration ...and frequency are specified.
Cardiovascular diseases are currently a basic cause of mortality in highly developed countries. The major reason for genesis and development of cardiovascular diseases is atherosclerosis. At the ...present time high technology methods of molecular genetic diagnostics can significantly simplify early presymptomatic recognition of patients with atherosclerosis, to detect risk groups and to perform a family analysis of this pathology. A Next-Generation Sequencing (NGS) technology can be characterized by high productivity and cheapness of full genome analysis of each DNA sample. We suppose that in the nearest future NGS methods will be widely used for scientific and diagnostic purposes, including personalized medicine. In the present review article literature data on using NGS technology were described in studying mitochondrial genome mutations associated with atherosclerosis and its risk factors, such as mitochondrial diabetes, mitochondrial cardiomyopathy, diabetic nephropathy and left ventricular hypertrophy. With the use of the NGS technology it proved to be possible to detect a range of homoplasmic and heteroplasmic mutations and mitochondrial genome haplogroups which are associated with these pathologies. Meanwhile some mutations and haplogroups were detected both in atherosclerosis and in its risk factors. It conveys the suggestion that there are common pathogenetic mechanisms causing these pathologies. What comes next? New paradigm of crosstalk between non-pharmaceutical (including molecular genetic) and true pharmaceutical approaches may be developed to fill the niche of effective and pathogenically targeted pretreatment and treatment of preclinical and subclinical atherosclerosis to avoid the development of chronic life-threatening disease.
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