Gas Density and the Volume Schmidt Law for Spiral Galaxies

The thickness of the equilibrium isothermal gaseous layers and their volume densities \rho_{gas}(R) in the disc midplane are calculated for 7 spiral galaxies (including our Galaxy) in the frame of self-consistent axisymmetric model. Local velocity dispersions of stellar discs were assumed to be close to marginal values necessary for the discs to be in a stable equilibrium state. Under this condition the stellar discs of at least 5 of 7 galaxies reveal a flaring. Their volume densities decrease with R faster than \rho_{gas}, and, as a result, the gas dominates by the density at the disc periphery. Comparison of the azimuthally averaged star formation rate SFR with the gas density shows that there is no universal Schmidt law SFR \rho_{gas}^n, common to all galaxies. Nevertheless, SFR in different galaxies reveals better correlation with the volume gas density than with the column one. Parameter n in the Schmidt law SFR \rho_{gas}^n, formally calculated by the least square method, lies within 0.8-2.4 range and it's mean value is close to 1.5. Values of n calculated for molecular gas only are characterized by large dispersion, but their mean value is close to 1. Hence the smaller \rho_{gas} the less is a fraction of gas actively taking part in the process of star formation.Comment: 24 pages, 11 figures, to be published in Astronomy Reports, 200

Midplane Gas Density and the Schmidt Law

The thickness of isothermal gaseous layers and their midplane volume densities \rho_{gas}(R) were calculated for several spiral and LSB galaxies by solving the self-consistent equilibrium equations for gaseous discs embedded into a stellar one. The self-gravity of the gas and influence of dark halo on the disk thickness were taken into account. The resulting midplane volume densities of spiral galaxies were compared with the azimuthally averaged star formation rate SFR to verify the feasibility and universality of the Schmidt law SFR ~ \rho_{gas}^n.Comment: 2 pages, 2 figures, proceeding of the poster presented at the Vatican Conf. "Formation and evolution of galaxy disks" held in Rome, 1-5 Oct. 200

Development of the New Method of the Melted Cheese Products Without Salt-melters Using Cryomechanolysis

The aim of the work is elaboration of the principally new method of deep processing of rennet cheeses to the melting using the complex action of freezing and cryomechanolysis on the raw material that gives a possibility to destruct the hardly soluble biopolymers and to transform them into soluble form.The principally new method of the deep processing of rennet cheeses for receiving the melt cheese products without salts-smelters was elaborated. It differs from the traditional ones by the complete exclusion of the salts-smelters. This method is based on the use of the influence of freezing and fine-dispersed comminution on the raw material. It allows open biological potential of the rennet cheeses more fully and to extract the hidden (bound) protein forms from nanocomplexes of lipids and mineral substances. It allows destruct the proteins of rennet cheeses to the separate polymers and dipeptides and tripeptides. The used technological methods gave a possibility to exclude the salts-smelters at the rennet cheeses manufacturing. They favor the transformation of lipid-proteins paracaseinate calcium phosphate complexes to the separate amino acids and peptides and allow receive homogenous plastic mass.It was established, that at the complex action of freezing and fine-dispersed comminution on the rennet cheese the destruction of hardly soluble lipid-protein nanocomplexes and release of protein from the bound state into free one – nanoform (by 33,5…35 % more) takes place. The mechanisms of this process, connected with cryomechanodestruction of connections between lipids and proteins and non-fermented catalysis of nanocomplexes were described.It was established, that cryomechanodestruction and non-fermented catalysis of protein to the separate monomers – α-amino acids (by 55…60 %) takes place at freezing and fine-dispersed comminution of rennet cheese before melting. The mechanism of freezing and non-fermented analysis, connected with cryomechanocracking of protein molecules at the expanse of peptide protein connections destruction to the separate α-amino acids and their transformation into the free form was described. It was also demonstrated, that the conformational changes of protein molecules take place synchronously.The offered and elaborated nanotechnology of melt cheese products on the base of rennet cheeses without salts-smelters includes complex action of freezing and fine-dispersed comminution. The mechanisms of processes, connected with cryomechanodestruction of connections between lipids and protein to the separate α-amino acids are described.The cheese fillings for “Pancake” confectionary and cheese snacks – falafels were manufactured on the base of cheese mass, received using the new method and enriching vegetable nanoadditives. They exceed the well-known analogs by chemical composition and are remarkable for the storage life, increased in 2 times. At the same time the significant part of substances (BAS and biopolymers) in cheese filings is in nanodimensional form (55…60 % of protein), especially, free α-amino acids, easily assimilated by the human organism. The recipes and technologies of sauces-dressings, sauces-deeps, cheese snacks and so on are also elaborated on the base of cheese mass, received by the new method

Radial HI Profiles at the Periphery of Galactic Disks: The Role of Ionizing Background Radiation

Observations of neutral hydrogen in spiral galaxies reveal a sharp cutoff in the radial density profile at some distance from the center. Using 22 galaxies with known HI distributions as an example, we discuss the question of whether this effect can be associated exclusively with external ionizing radiation, as is commonly assumed. We show that before the surface density reaches $\sigma_{\textrm{HI}}\le 0.5 {\cal M}_\odot/{\textrm {pc}}^2$(the same for galaxies of different types), it is hard to expect the gas to be fully ionized by background radiation. For two of 13 galaxies with a sharp drop in the HI profile, the "steepening" can actually be caused by ionization. At the same time, for the remaining galaxies, the observed cutoff in the radial HI profile is closer to the center than if it was a consequence of ionization by background radiation and, therefore, it should be caused by other factors.Comment: 15 pages, 6 figure

Student Evaluation of Teaching: More Harm than Good?

Student evaluation of teaching (SET) has more than forty years of history as a tool of feedback in North American, Australian and European universities. In Russian universities it is not widespread, although increasing its implementation could solve the problem of Russian students feeling that they are not involved in the management of the educational process and improve the quality of courses and teaching. The barriers to the implementation of SET in the Russian higher education system, among other things, are concerns and prejudices of teachers and students, who see SET more as a problem than an effective tool. In this article, authors analyze the most common faculty concerns about student evaluations of teaching, obtained from ten focus groups in five Russian universities. Authors put collected opinions in the context of the recent methodological discussions about the validity of Student Evaluations of Teaching. The main idea is that SET is an effective tool of getting feedback in higher education and involvement of students and teachers in a dialogue and cooperation in the educational process, but highly questionable as a data source for administrative decisions

The role of polymorphism of hereditary thrombophilia candidate genes in the development of arterial hypertension in women with preeclampsia

Preeclampsia is a severe pregnancy complication that has long been one of the leading causes of maternal and perinatal mortality and morbidity worldwide. Despite the achievements of modern medicine, the etiology of this pathology is not known. Multiple risk factors for the development of PE have been identified: arterial hypertension, diabetes mellitus, obesity, a hereditary history of preeclampsia, thrombophilia, etc., but recently, special attention has been paid to genetic determinants, namely, the contribution of individual polymorphic loci of various gene

Micro-relief and roughness of the surface of the profiled sulfocation-exchange membrane after its contact with phenylalanine solution

The work was conducted under financial support of RFBR (project N 18-08-01260)