41 research outputs found

    Theoretical correlation between possible evidences of neutrino chiral oscillations and polarization measurements

    Full text link
    Reporting about the formalism with the Dirac equation we describe the dynamics of chiral oscillations for a fermionic particle non-minimally coupling with an external magnetic field. For massive particles, the chirality and helicity quantum numbers represent different physical quantities of representative importance in the study of chiral interactions, in particular, in the context of neutrino physics. After solving the interacting Hamiltonian (Dirac) equation for the corresponding {\em fermionic} Dirac-{\em type} particle (neutrino) and quantifying chiral oscillations in the Dirac wave packet framework, we avail the possibility of determining realistic neutrino chirality conversion rates by means of (helicity) polarization measurements. We notice that it can become feasible for some particular magnetic field configurations with large values of {\boldmathBB} orthogonal to the direction of the propagating particle.Comment: 12 pages, 2 figure

    Features of procrastination in medical students with different levels of internet addiction

    Get PDF
    The article presents the results of a study of the prevalence of procrastination in the student environment. Attention is focused on the presence of the relationship of procrastination with some personal characteristics and Internet addiction in medical students. Peculiarities of expression of academic procrastination among young people with different levels of Internet addiction are describedВ статье представлены результаты исследования распространённости и особенности прокрастинации у студентов. Акцентировано внимание на наличии взаимосвязи прокрастинации с некоторыми личностными характеристиками и интернет-аддикцией у студентов-медиков. Описаны особенности выраженности академической прокрастинации у молодых людей с разным уровнем интернет-аддикци

    Laparoscopic retropubic extraurethral adenomectomy

    Get PDF
    Introduction. Existing methods of surgical treatment of benign prostatic hyperplasia are accompanied by the frequent development of postoperative complications, such as urinary incontinence, retrograde ejaculation, and urethral strictures. The method of preserving the prostatic urethra has been developed for a long time. At present, it is possible to use the operation technique and perform laparoscopic urethral-sparing adenomectomy.Objective. To assess the possibility of performing extraurethral adenomectomy with prostatic urethral preservation using the laparoscopic approach, its advantages and disadvantages.Materials and methods. Based on St. Luke’s Simferopol сlinical Multidisciplinary Medical Center, 35 successful laparoscopic operations were performed to remove benign prostate hyperplasia with the prostatic urethra preservation. The features of the operation are laparoscopic access, a transverse section of the capsule, alternate isolation of adenomatous nodes while preserving the prostatic urethra on the catheter without replacing it during the operation, suturing the capsule with a decrease in space from the removed adenomatous nodes. Urethral preservation provided accelerated epithelialization of the defect, in the absence of the formation of a “prevesical” space.Results. After the operation, it is possible to turn off the urinary bladder irrigation system earlier (up to 4 – 6 hours after the operation) and early removal of the catheter after surgery (2 – 3 days). The hospital stay averaged 5.7 days. Urination was restored immediately after catheter removal in 92% of the patients. There were no elements of dysuria, particularly urinary incontinence. Prostate volume measured throughout transrectal ultrasound after operation was 20 – 24 cm³.Conclusion. The technique of retropubic extraurethral adenomectomy with prostatic urethral preservation can be performed in laparoscopic technique. The advantages are early activation of the patient and discharge from the hospital, early removal of the catheter with restoration of independent urination, absence of dysuria, urinary incontinence, and postoperative complications. The results of our study demonstrate the effectiveness of the laparoscopic extraurethral adenomectomy technique, the further development of this technique, and the possibility of its application in practice

    Halophilic bacteria of salt lakes and saline soils of the Peri-Caspian lowland (Republic of Daghestan) and their biotechnological potential

    Get PDF
    The article presents the results of studying the biodiversity and biotechnological potential of halophilic microorganisms from the thermal highly mineralized Berikey Lake, the salty Lake Tarumovskoye and saline soils of the Peri-Caspian Lowland (Republic of Daghestan). Denitrifying halophilic bacteria of the genus Halomonas and Virgibacillus were identified using microbiological methods and 16S rRNA gene analysis. A new species Halomonas sp. G2 (MW386470) with a similarity of the nucleotide sequences of the 16S rRNA genes is 95 %. Strain G2 is an extreme halophile capable of growing in the range of 5–25 % NaCl (optimum 25 %) and forming a carotenoid pigment. Mesophil, 30–37 °С (optimum 30 °С); neutrophil, pH 6–8 (optimum 7.2–7.4). Strain G2 chemolithotroph; reduces nitrate or nitrite as electron donors; catalase-, amylase-, protease- and β-galactosidase-positive; lipase-, oxidase- and urease-negative. Not able to hydrolyze inositol, indole; produces lysine, gelatin, ectoine; uses citrate and sodium malate as a source of carbon and energy; does not produce ornitin, H2S or acid from d-mannose, sucrose, glycerol, cellobiose, except for lactose and d-glucose. Susceptible to trimethoprim, ciprofloxacin, ofloxacin, kanamycin, vancomycin, rifampicin, cefuroxime, ampicillin, ceftazidime, fosfomycin, clarithromycin, cefepime, cefaclor. The G+C content in DNA is 67.3 %. A distinctive characteristic of the isolate was the production of industrially significant hydrolytic enzymes such as amylase, protease, β-galactosidase, and oxidoreductase (catalase) at a NaCl concentration of 25 % in the medium. Habitat: saline soils on the territory of the Tersko-Kumskaya lowland (Republic of Daghestan, Russia). The rest of the halophilic isolates of H. ventosae G1 (MW386469), H. elongata G3 (MW386471), V. salinarius B2 (MW386472), and V. salinarius B3 (MW386473) had a high degree of similarity (100 %) with the type strains of H. elongata DSM 2581Т and V. salarius DSM 18441Т; the content of G+C in DNA was 65.8, 66.5, 42.8 and 37.3 %, respectively. The strains had a high biotechnological potential at NaCl concentrations of 5 and 25 % in the medium. The data obtained expanded the understanding of the diversity and ecological significance of denitrifying bacteria in the functioning of arid ecosystems and make it possible to identify strains producing enzymes of industrial importance

    Particle and Antiparticle sectors in DSR1 and kappa-Minkowski space-time

    Full text link
    In this paper we explore the problem of antiparticles in DSR1 and κ\kappa-Minkowski space-time following three different approaches inspired by the Lorentz invariant case: a) the dispersion relation, b) the Dirac equation in space-time and c) the Dirac equation in momentum space. We find that it is possible to define a map SdsrS_{dsr} which gives the antiparticle sector from the negative frequency solutions of the wave equation. In κ\kappa-Poincar\'e, the corresponding map SkpS_{kp} is the antipodal mapping, which is different from SdsrS_{dsr}. The difference is related to the composition law, which is crucial to define the multiparticle sector of the theory. This discussion permits to show that the energy of the antiparticle in DSR is the positive root of the dispersion relation, which is consistent with phenomenological approaches.Comment: 15 pages, no figures, some references added, typos correcte

    Competitiveness of professional education: Purposes, tasks and factors of its participation in the international educational services market

    Get PDF
    © 2014 Copyright for this article is retained by the author(s). The article is directed at research of professional education competitiveness problem under the conditions of the international educational integration. The essence of competitiveness of professional education is revealed in it and such components as: competitiveness of specialty and higher educational institution, competitiveness of vocational training, competitiveness of educational services, competitiveness of a student, competitiveness of a graduate and competitiveness of an expert are also revealed here. The purposes and tasks are presented in the article, the features of competitiveness of professional education are revealed, and also factors of competitive participation of the Russian professional education at the international market of educational services are defined

    Factors influencing the severity of COVID-19 course for patients with diabetes mellitus in tashkent: a retrospective cohort study

    Get PDF
    BACKGROUND: Since the very first outbreak, scientists have been trying to determine the most critical pathogenetic mechanisms for the development of COVID-19 and related complications, analyze individual subpopulations of patients with chronic diseases and develop optimal tactics to combat not only the infection itself but also its acute and chronic complications.AIM: to assess the COVID-19 course among patients with Type 1 and Type 2 DM.MATERIALS AND METHODS: A retrospective cohort study of Tashkent inhabitants, who had COVID-19 from April to D ecember 2020, was performed. The data were obtained from the single electronic database of registered cases of COVID-19. All data were analyzed using a logistic regression in STATA 17.0 software. Further, the matched case-control study was performed for patients with type 2 DM and no DM based on age, gender, and BMI.RESULTS: Of the 5023 analyzed subjects, 72.63% had no diabetes mellitus (DM), 4.24% had type 1 DM, 15.19% had type 2 DM, and 7.94% was diagnosed with DM during the COVID-19 infection. DM, overweight, and obesity were associated with severe COVID-19; the most significant risk of a severe course was found in persons with type 2 DM. The risk of a lethal outcome and the need for prescription of glucocorticoids did not show a significant association with diabetes in Tashkent. The clinical features of COVID-19 were more common in patients with type 2 DM, especially for shortness of breath, chest pain, and arrhythmia. The persons receiving SU have complained of dyspnea significantly more often than matched patients without DM. Metformin and DPP4i were the groups of drugs that were not associated with significantly increased risk of hospitalization of patients because of COVID-19. The matched case-control study did not reveal statistically significant differences in the disease course severity, need for hospitalization and glucocorticoids, and death depending on the glucose-lowering therapy preceding the onset of COVID-19.CONCLUSION: Diabetes, age and overweight/obesity were associated with severe course of COVID-19 in Tashkent. There was no statistical difference in COVID-19 severity depending on initial glucose-lowering therapy

    Special relativity with two invariant scales: Motivation, Fermions, Bosons, Locality, and Critique

    Full text link
    We present a Master equation for description of fermions and bosons for special relativities with two invariant scales, SR2, (c and lambda_P). We introduce canonically-conjugate variables (chi^0, chi) to (epsilon, pi) of Judes-Visser. Together, they bring in a formal element of linearity and locality in an otherwise non-linear and non-local theory. Special relativities with two invariant scales provide all corrections, say, to the standard model of the high energy physics, in terms of one fundamental constant, lambda_P. It is emphasized that spacetime of special relativities with two invariant scales carries an intrinsic quantum-gravitational character. In an addenda, we also comment on the physical importance of a phase factor that the whole literature on the subject has missed and present a brief critique of SR2. In addition, we remark that the most natural and physically viable SR2 shall require momentum-space and spacetime to be non-commutative with the non-commutativity determined by the spin content and C, P, and T properties of the examined representation space. Therefore, in a physically successful SR2, the notion of spacetime is expected to be deeply intertwined with specific properties of the test particle.Comment: Int. J. Mod. Phys. D (in press). Extended version of a set of two informal lectures given in "La Sapienza" (Rome, May 2001

    Spin half fermions with mass dimension one: theory, phenomenology, and dark matter

    Full text link
    We provide the first details on the unexpected theoretical discovery of a spin-one-half matter field with mass dimension one. It is based upon a complete set of dual-helicity eigenspinors of the charge conjugation operator. Due to its unusual properties with respect to charge conjugation and parity, it belongs to a non-standard Wigner class. Consequently, the theory exhibits non-locality with (CPT)^2 = - I. We briefly discuss its relevance to the cosmological `horizon problem'. Because the introduced fermionic field is endowed with mass dimension one, it can carry a quartic self-interaction. Its dominant interaction with known forms of matter is via Higgs, and with gravity. This aspect leads us to contemplate the new fermion as a prime dark matter candidate. Taking this suggestion seriously we study a supernova-like explosion of a galactic-mass dark matter cloud to set limits on the mass of the new particle and present a calculation on relic abundance to constrain the relevant cross-section. The analysis favours light mass (roughly 20 MeV) and relevant cross-section of about 2 pb. Similarities and differences with the WIMP and mirror matter proposals for dark matter are enumerated. In a critique of the theory we bare a hint on non-commutative aspects of spacetime, and energy-momentum space.Comment: 78 pages [Changes: referee-suggested improvements, additional important references, and better readability

    Doubly Special Relativity and de Sitter space

    Full text link
    In this paper we recall the construction of Doubly Special Relativity (DSR) as a theory with energy-momentum space being the four dimensional de Sitter space. Then the bases of the DSR theory can be understood as different coordinate systems on this space. We investigate the emerging geometrical picture of Doubly Special Relativity by presenting the basis independent features of DSR that include the non-commutative structure of space-time and the phase space algebra. Next we investigate the relation between our geometric formulation and the one based on quantum κ\kappa-deformations of the Poincar\'e algebra. Finally we re-derive the five-dimensional differential calculus using the geometric method, and use it to write down the deformed Klein-Gordon equation and to analyze its plane wave solutions.Comment: 26 pages, one formula (67) corrected; some remarks adde
    corecore