6,897 research outputs found
Methods for deriving the law of radioactive decay and the law of radiation absorption using the property of the exponent function when studying Physics in the system of secondary vocational education
In accordance with the educational standards of the Federal State Educational Standard for Secondary Professional Education, it is intended to familiarize students of professional educational organizations with the properties of radioactive radiation, their practical applications, as well as with some concepts of dosimetry and protection from such radiation.The relevance of this research can be debated for a very long time. But in light of recent events it is obvious.A thorough mastery of all this material is impossible without studying the law of radioactive decay and the law of absorption of radiation.The research problem: the law of radioactive decay and the law of absorption of radiation are expressed using the exponential function N=N_0 e^(-λt) and i=Ie^(-μχ) and are usually not presented in the course of Physics in secondary specialized educational institutions. At best, an appropriate schedule is drawn, but without justification. It seems that this is caused by two reasons: firstly, when writing the exponent function, the base of natural logarithms is used – the number e, which is unknown to intermediate students; secondly, the above laws are usually derived by solving differential equations, which is far beyond the scope of the mathematics curriculum. Meanwhile, both of these difficulties can be easily overcome by using the properties of the exponential function known to students of secondary vocational education.The purpose of the research is to develop a methodology for deriving the law of radioactive decay and the law of radiation absorption, using the properties of the exponential function; to conduct a pedagogical experiment in order to identify the problem of students’ mastery of the proposed material.The research methods used are theoretical justification; calculation; comparison of quantities; graphical analysis of experimental data; generalization of the experimental factors of the study and their explanation.The research results: a methodology has been developed for deriving the law of radioactive decay and the law of radiation absorption using the property of the exponential function; the result of the pedagogical experiment confirmed the effectiveness of the developed methodology.Key conclusions: from the proposed article we can conclude that the presented method for deriving the law of radioactive decay and the law of absorption of radiation using the property of the exponent function can be used by teachers when studying the section «Radioactive Radiation» for both students of professional educational organizations and school students (advanced level)
HLA-B27-associated uveitis: From pathogenesis to therapy
Uveitis is the inflammation of the uvea, which generally occurs in young people and may be accompanied by serious complications leading to disability. The review analyzes the data of Russian and foreign investigations on the pathogenesis of HLA-B27-associated uveitis occurring in different diseases from a group of seronegative spondyloarthritides (SpA) and also discusses current therapeutic approaches in this disease.Since the late 20th century, there has been rapid progress in studying the pathogenesis of HLA-B27-associated uveitis and in identifying the genetic factors predisposing to this pathology. Investigations of HLA-B27 antigen and its alleles are being continued. Tumor necrosis factor-α (TNF-α), the higher levels of which in blood, synovial fluid, and ocular fluid in rheumatic diseases has been proven in many works of both foreign and Russian scientists, is most studied among the inflammatory mediators. Due to the key role of this cytokine in the development of inflammation, drugs inhibiting TNF-α activity have been designed and successfully used in the past decade, which results in partial and occasionally stable remission
HLA-B27-ASSOCIATED UVEITIS: EPIDEMIOLOGY, CLINICAL PICTURE, AND COMPLICATIONS
Anterior uveitis is the most common form of intraocular inflammation. Among them, HLA-B27-associated uveitis occupies one of the leading places, which may be an independent disease or one of the manifestations of spondy- loarthritis (SA). The paper considers the general issues of the nomenclature and classification of uveitis, by using the classification criteria of the International Uveitis Study Group and the Standardization of Uveitis Nomenclature Workshop. The epidemiological aspects of uveitis are described. Emphasis is laid on a difference in the detection rate of uveitis in different countries, in men and women, as well as in different forms of SA. The clinical features of SA- associated uveitis and its complications are discussed
Charm-sea Contribution to High-p_T \psi Production at the Fermilab Tevatron
The direct production of at large transverse momentum, , at the Fermilab Tevatron is revisited. It is found that the
sea-quark initiated processes dominate in the high- region within the
framework of color-singlet model, which is not widely realized. We think this
finding is enlightening for further investigation on the charmonium production
mechanism.Comment: Conclusions not changed, to appear in J. of Phys.
Методы лучевой диагностики как инструмент мониторинга аксиального спондилоартрита в реальной клинической практике
The article summarizes literature data on the use of radiography and magnetic resonance imaging to monitor axial spondyloarthritis in real clinical practice.В статье обобщены данные литературы об использовании рентгенографии и магнитно-резонансной томографии с целью мониторинга аксиального спондилоартрита в реальной клинической практике
The study of the chemical composition of sorption substances
The article presents a study of the chemical composition of sorption substances. The chemical composition is established, the main prevailing elements and impurities are revealed. The crystal-chemical structure of sorption substances is proposed. A comparative analysis of the chemical composition and the classification of sorption substances, depending on the origi
Prospect for Searches for Gluinos and Squarks at a Tevatron Tripler
We examine the discovery potential for SUSY new physics at a p{\bar p}
collider upgrade of Tevatron with \sqrt s = 5.4 TeV and luminosity L ~= 4\times
10^{32} cm^{-2}s^{-1} (the Tripler). We consider the reach for gluinos and
squarks using the experimental signatures with large missing transverse energy
(\met) of jets + \met and 1l + jets + \met (where l=electron or muon) within
the framework of minimal supergravity. The Tripler's strongest reach for the
gluino is 1060 GeV for the jets + \met channel and 1140 GeV for the 1l + jets +
\met channel for 30 fb^{-1} of integrated luminosity (approximately two years
running time). This is to be compared with the Tevatron where the reach is
440(460) GeV in the jets + \met channel for 15(30) fb^{-1} of integrated
luminosity.Comment: 17 pages, latex, 7 figure
Physics Beyond the Standard Model
I briefly summarize the prospects for extending our understanding of physics
beyond the standard model within the next five years.Comment: 9 pages, 2 figures, LaTeX. Presented at the 1999 UK Phenomenology
Workshop, Durham, September 1999. To be published in Journal of Physics
Poloxomer 188 Has a Deleterious Effect on Dystrophic Skeletal Muscle Function
Duchenne muscular dystrophy (DMD) is an X-linked, fatal muscle wasting disease for which there is currently no cure and limited palliative treatments. Poloxomer 188 (P188) is a tri-block copolymer that has been proposed as a potential treatment for cardiomyopathy in DMD patients. Despite the reported beneficial effects of P188 on dystrophic cardiac muscle function, the effects of P188 on dystrophic skeletal muscle function are relatively unknown. Mdx mice were injected intraperitoneally with 460 mg/kg or 30 mg/kg P188 dissolved in saline, or saline alone (control). The effect of single-dose and 2-week daily treatment was assessed using a muscle function test on the Tibialis Anterior (TA) muscle in situ in anaesthetised mice. The test comprises a warm up, measurement of the force-frequency relationship and a series of eccentric contractions with a 10% stretch that have previously been shown to cause a drop in maximum force in mdx mice. After 2 weeks of P188 treatment at either 30 or 460 mg/kg/day the drop in maximum force produced following eccentric contractions was significantly greater than that seen in saline treated control mice (P = 0.0001). Two week P188 treatment at either dose did not significantly change the force-frequency relationship or maximum isometric specific force produced by the TA muscle. In conclusion P188 treatment increases susceptibility to contraction-induced injury following eccentric contractions in dystrophic skeletal muscle and hence its suitability as a potential therapeutic for DMD should be reconsidered
New approach to drug delivery in ophthalmological practice: development of composite ophthalmological solution for drug loading of soft contact lenses
The aim of the research is to develop the composition of the ophthalmic transport system for the treatment of glaucoma. Also, the proposed manufacturing algorithms were proposed for drug loading ophthalmological solution
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