Origin of the peaks in the Nernst coefficient of bismuth in strong magnetic fields

We explain the origin of most of the peaks in the Nernst coefficient that were recently observed at magnetic fields directed along the trigonal axis and the bisectrix direction in bismuth. Additional experiments are discussed that enable one to verify our explanation.Comment: Submitted to Physical Review B. 4 pages, 5 figure

Surface superconducting states in yttrium hexaboride single crystal in a tilted magnetic field

We present the results of an experimental study of the nucleation of superconductivity at the surface of a single crystal YB$_6$ in a tilted dc magnetic field. A recently developed experimental technique allowed us to determine $H_{c3}$ at each side of the sample as a function of the angle between the dc magnetic field and the surface. Experiment shows that the ratio $H_{c3}/ H_{c2}\approx 1.28$ in the direction perpendicular to the surface dc field while according to the theory this ratio should be equal to 1. This sharp distinction cannot be ascribed to the surface roughness.Comment: 6 pages, 8 figure

Study of the properties of Plessey's electrocardiographic capacitive electrodes for portable systems

Cardiac diseases are still most widely spread in all regions of the world. And more and more devices are invented to satisfy increasing requirements of the patients. One of the perspective technologies in cardiac diagnostics is capacitive sensing ECG electrodes

Texture Analysis of CT Images in Head and Neck Tumors Differentiation

Objective: to determine the diagnostic significance of computed tomography texture analysis (CTTA) in differentiating head and neck tumors.Material and methods. The study included 118 patients aged from 4 to 80 years with a verified diagnosis of benign and malignant (37 and 81, respectively) head and neck tumors. CTTA was performed using the LIFEx program, version 6.30. Thirty eight (38) texture indices extracted from routine CT images were tested by regression analysis with creation of logistic texture models with associations of four indices as independent predictors.Results. The possibility of using derived models – probability textural indices for benign and malignant tumors differentiation was established: area under ROC-curve (AUC) 0.854 ± 0.035 (p < 0.001); for differentiation of locally spread from locally limited tumors: AUC 0.840 ± 0.049 (p < 0.001); for differentiation of moderately, poorly, and undifferentiated cancer (G2, G3, G4) from well-differentiated (G1) head and neck cancer: AUC 0.826 ± 0.085 (p < 0.001).Conclusion. CT images texture analysis allows to make non-invasive prognosis of benign or malignant nature of a visualized head and neck tumor, as well as to determine the extent and degree of tumor malignancy

Challenges of beta-deformation

A brief review of problems, arising in the study of the beta-deformation, also known as "refinement", which appears as a central difficult element in a number of related modern subjects: beta \neq 1 is responsible for deviation from free fermions in 2d conformal theories, from symmetric omega-backgrounds with epsilon_2 = - epsilon_1 in instanton sums in 4d SYM theories, from eigenvalue matrix models to beta-ensembles, from HOMFLY to super-polynomials in Chern-Simons theory, from quantum groups to elliptic and hyperbolic algebras etc. The main attention is paid to the context of AGT relation and its possible generalizations.Comment: 20 page

Exact 2-point function in Hermitian matrix model

J. Harer and D. Zagier have found a strikingly simple generating function for exact (all-genera) 1-point correlators in the Gaussian Hermitian matrix model. In this paper we generalize their result to 2-point correlators, using Toda integrability of the model. Remarkably, this exact 2-point correlation function turns out to be an elementary function - arctangent. Relation to the standard 2-point resolvents is pointed out. Some attempts of generalization to 3-point and higher functions are described.Comment: 31 pages, 1 figur

Nuclear Receptor Rev-erb Alpha (Nr1d1) Functions in Concert with Nr2e3 to Regulate Transcriptional Networks in the Retina

The majority of diseases in the retina are caused by genetic mutations affecting the development and function of photoreceptor cells. The transcriptional networks directing these processes are regulated by genes such as nuclear hormone receptors. The nuclear hormone receptor gene Rev-erb alpha/Nr1d1 has been widely studied for its role in the circadian cycle and cell metabolism, however its role in the retina is unknown. In order to understand the role of Rev-erb alpha/Nr1d1 in the retina, we evaluated the effects of loss of Nr1d1 to the developing retina and its co-regulation with the photoreceptor-specific nuclear receptor gene Nr2e3 in the developing and mature retina. Knock-down of Nr1d1 expression in the developing retina results in pan-retinal spotting and reduced retinal function by electroretinogram. Our studies show that NR1D1 protein is co-expressed with NR2E3 in the outer neuroblastic layer of the developing mouse retina. In the adult retina, NR1D1 is expressed in the ganglion cell layer and is co-expressed with NR2E3 in the outer nuclear layer, within rods and cones. Several genes co-targeted by NR2E3 and NR1D1 were identified that include: Nr2c1, Recoverin, Rgr, Rarres2, Pde8a, and Nupr1. We examined the cyclic expression of Nr1d1 and Nr2e3 over a twenty-four hour period and observed that both nuclear receptors cycle in a similar manner. Taken together, these studies reveal a novel role for Nr1d1, in conjunction with its cofactor Nr2e3, in regulating transcriptional networks critical for photoreceptor development and function

Experience in International Cooperation on Organization of Anti-Epidemic Measures by Health Care Institutions under COVID-19 Pandemic in the Republic of Uzbekistan

The results of the joint work of a panel of experts from Rospotrebnadzor and healthcare professionals of the Republic of Uzbekistan on organizing activities to counter the spread of the SARS-CoV-2 virus are described in the paper.The goal of the study was to determine the main driving forces of COVID-19 spread in the Republic of Uzbekistan and develop an action plan to reduce the incidence of coronavirus infection caused by the SARS-CoV-2 virus.Materials and methods. The organization of work in 14 health care institutions in Tashkent and Samarkand, as well as in Tashkent and Samarkand Regions, was analyzed: in 7 laboratories, 6 hospitals and 1 polyclinic. The routes for the movement of personnel, the demarcation of green and red zones, the features of disinfection and the use of personal protective equipment were studied. Attention is drawn to the diagnosis of COVID-19, the use of therapy aimed at reducing the period of virus shedding, the criteria for lifting quarantine restrictions for patients.Results and discussion. The main factors in the organization of work of institutions that contribute to the spread of COVID-19 among medical personnel and the population have been identifed: the lack of equipped gateways between the red and green zones with the accessibility of adequate disinfection, the wrong choice of personal protective equipment, monitoring of contact persons for 10 days, discharge from hospitals based on clinical improvement. The incorrect use of antiviral therapy, the lack of differentiated approaches to the selection of optimal regimens have been noted. Proposals are formulated for organizing the work of healthcare institutions, taking into account the requirements of biological safety. The introduction of targeted measures in addition to those previously adopted has led to a signifcant improvement in the epidemic situation: the total number of active cases in the Republic of Uzbekistan, despite the increase in testing volumes, decreased from 3,686 people on August 23 to 2335 on October 27. Towards December 20, 2020, 97 % of patients recovered completely. All diagnostic triage centers in the Republic of Uzbekistan are closed due to the absence of patients with COVID-19, most of the country’s medical institutions previously re-profled for patients with coronavirus infection have returned to the routine operations