Modulation of Circumstellar Extinction in a Young Binary System with a Low-Mass Companion in a Noncoplanar Orbit

The cyclic activity model of a young star with the low-mass secondary component (q = M2/M1 <= 0.1) accreting a matter from circumbinary disk is considered. It is assumed that the orbit is circular and the disk and orbital planes are non-coplanar. Sets of hydrodynamics models of such a system have been calculated by the SPH method and then the variations of the circumstellar extinction and phase light curves were determined. The calculations showed that depending on the model parameters and orientation of the system in regards to an observer the different in shape and amplitude light curves can be observed. An important property of the considered models is also the dependence of the mass accretion rate onto the components on the phase of the orbital period. The results of the calculation can be used for analysis of the cyclic activity of UX Ori stars and young stars with the long-lasting eclipses.Comment: 14 pages, 7 figure

Dietary fiber is a reliable and apparent element of treatment for patients with type 2 diabetes mellitus and cardiovascular diseases: an easy solution to a complicated problem

Cardiovascular diseases are a frequent comorbid condition in patients with type 2 diabetes mellitus (t2DM). This problem tends to remain acute because of the progression of t2DM, which increases the chances of cardiovascular events. Medicine today has a range of innovative hypoglycemic drugs, which proved their safety and effectiveness towards diseases of cardiovascular system. However, high cardiovascular mortality demonstrates that the medication is not enough effective. Partly lack of success may be explained by not enough work with unmodified risk factors, such as physical activity, smoking and excessive and wrong nutrition. Studies about dietary fiber (DF) let us discuss their including in the dietary plan of patients with t2DM and cardiovascular diseases. One of the promising DF types is Cyamopsis tetragonoloba extract. It showed its effectiveness concerning carbohydrate metabolism and lipid profile, improving, metabolic features of t2DM patients and lowering the risks of cardiovascular events. What is more, the advantage of Cyamopsis tetragonoloba extract is easy to use and has no side effects

Clinical characteristics of patients with COVID-19 depending on the treatment received and the presence of type 2 diabetes mellitus

BACKGROUND. Type 2 diabetes mellitus (T2DM) is an independent risk factor for adverse clinical outcomes in patients with Covid-19. There is currently insufficient data evaluating the efficacy and safety of drugs for the treatment of COVID-19, especially in patients with T2DM.AIM. The aim of study was to identify an associative relationship between the drugs used and the clinical outcomes of patients with Covid-19 and T2DM.MATERIALS AND METHODS. A retrospective analysis of the clinical outcomes of 1753 patients with COVID-19 who were hospitalized to the redesignated departments of multidisciplinary city clinical hospital in the period from 23.03.2020 to 01.06.2020.RESULTS. The total number of patients is 1,753, of which 311 (17.7%) are patients with DM2. 92.6% of patients received treatment for COVID-19. At the same time, 91.4% of patients received antibiotics (a/b), 61.5% — bronchodilators, 56.6% — injectable anticoagulants (a/c), 45.2% — hydroxychloroquine, 6.3% — antiviral drugs, 5.4% — oral a/c, 4.6% — glucocorticosteroids (GCS), 1.9% — Tocilizumab.Decrease of risk of death among patients with COVID-19 was as the therapy of a/b (OR 0.07, 95% CI 0.05–0.11, p&lt;0.05), bronchodilators (OR 0.12, 95% CI 0.08–0.18, p&lt;0.05) and injection a/c (OR 0.47, 95% CI 0.34–0.67, p&lt;0.05). At the same time, among patients with DM2, compared with patients without DM2, there was a more pronounced reduction in the risk of death during injectable a/c therapy: among patients with DM2, the risk of death decreased by 2.6 times (OR 0.39, 95% CI 0.21–0.73, p&lt;0.05), among patients without DM2 — by 2.1 times (OR 0.47, 95% CI 0.31–0.71, p&lt;0.05). Antiviral drugs was associated with an increased chance of death among patients without DM2 (OR 2.64, 95% CI 1.44–4.86, p&lt;0.05) and among patients with DM2 (OR 4.98, 95% CI 2.11–11.75, p&lt;0.05).CONCLUSION. A significant decrease of the risk of death among patients with COVID-19 was as the therapy of a/b, bronchodilators, and injectable a/c. An increase of the risk of death was observed during therapy with antiviral drugs

Escherichia coli stress response systems and their reaction to terahertz radiation

In this review, we summarize the latest data concerning the reactions of Escherichia coli to nonthermal terahertz radiation and the underlying molecular mechanisms. E. coli is the most simple and convenient model object for studying the effects of terahertz radiation: both its genetics and metabolism are well studied, and it is easily amenable to genetic engineering allowing one to create biosensors using promoters of genes activated by certain stress factors and the reporter GFP protein. Transformed E. coli cells containing biosensors can be used to visualize their reactions to terahertz radiation based on the intensity of GFP fluorescence. In this review, we present data on the response of certain E. сoli stress response systems to terahertz radiation obtained by us, as well as by other authors. We discuss experimental results for E. сoli/ pKatG-GFP, E. сoli/pCopA-GFP, and E. сoli/ pEmrR-GFP biosensors that are used to detect E. сoli genetic networks responding to oxidative stress, copper ion homeostasis failures, and antiseptics, respectively. The obtained data indicate that exposure to nonthermal terahertz radiation induces E. сoli gene networks of oxidative stress and copper ion homeostasis, but does not activate those responding to antibiotics, protonophores, or superoxide anions. The fact that E. сoli/pKatG-GFP and E. сoli/pCopA-GFP biosensors have different activation and reaction periods when exposed to terahertz radiation and natural inducers suggests that reactions of oxidative stress and copper ion homeostasis systems to terahertz radiation are specific

Bimodal Brightness Oscillations in Models of Young Binary Systems

We consider a model for the cyclic activity of young binary stars that accrete matter from the remnants of a protostellar cloud. If the orbit of such a binary system is inclined at a small angle to the line of sight, then the streams of matter and the density waves excited in the circumbinary disk can screen the primary component of the binary from the observer. To study these phenomena by the SPH (smoothed particle hydrodynamics) method, we have computed grids of hydrodynamic models for binary systems based on which we have constructed the light curves as a function of the orbital phase.The main emphasis is on investigating the properties of the brightness oscillations. Therefore, the model parameters were varied within the following ranges: the component mass ratio q = M2 : M1 = 0.2 - 0.5 and the eccentricity e = 0 - 0.7. The parameter that defined the binary viscosity was also varied. We adopted optical grain characteristics typical of circumstellar dust. Our computations have shown that bimodal oscillations are excited in binaries with eccentric orbits, provided that the binary components do not differ too much in mass. In this case, the ratios of the periods and amplitudes of the bimodal oscillations and their shape depend strongly on the inclination of the binary plane and its orientation relative to the observer. Our analysis shows that the computed light curves can be used in interpreting the cyclic activity of UX Ori stars.Comment: 14 pages, 5 figures, 1 tabl

Brightness Oscillations in Models of Young Binary Systems with Low-Mass Secondary Components

We consider a model for the cyclic brightness variations of a young star with a low-mass companion that accretes matter from the remnants of a protostellar cloud. At small inclinations of the binary orbit to the line of sight, the streams of matter and the density waves excited in the circumbinary disk can screen the primary component of the binary from the observer. To study these phenomena, we have computed grids of hydrodynamic models for binary systems by the SPH method based on which we have constructed the phase light curves as a function of the rotation angle of the apsidal line relative to the observer. The model parameters were varied within the following ranges: the component mass ratio q = 0.01-0.1 and the eccentricity e = 0-0.5. We adopted optical grain characteristics typical of circumstellar dust. Our computations have shown that the brightness oscillations with orbital phase can have a complex structure. The amplitudes and shapes of the light curves depend strongly on the inclination of the binary orbit and its orientation relative to the observer and on the accretion rate. The results of our computations are used to analyze the cyclic activity of UX Ori stars.Comment: 13 pages,8 figures, 1 tabl

Formation of 24Mg* in the Splitting of 28Si Nuclei by 1-GeV Protons

The 28Si(p, p' gamma)24Mg reaction has been studied at the ITEP accelerator by the hadron-gamma coincidence method for a proton energy of 1 GeV. Two reaction products are detected: a 1368.6-keV gamma-ray photon accompanying the transition of the 24Mg* nucleus from the first excited state to the ground state and a proton p' whose momentum is measured in a magnetic spectrometer. The measured distribution in the energy lost by the proton in interaction is attributed to five processes: the direct knockout of a nuclear alpha cluster, the knockout of four nucleons with a total charge number of 2, the formation of the DeltaSi isobaric nucleus, the formation of the Delta isobar in the interaction of the incident proton with a nuclear nucleon, and the production of a pi meson, which is at rest in the nuclear reference frame. The last process likely corresponds to the reaction of the formation of a deeply bound pion state in the 28P nucleus. Such states were previously observed only on heavy nuclei. The cross sections for the listed processes have been estimated.Comment: 14 pages, 3 figures submitted to JETP Letter