234 research outputs found
Various types of completeness in topologized semilattices
A topologized semilattice X is called complete if each non-empty chain C⊂ X has inf C and sup C that belong to the closure C¯ of the chain C in X. In this paper, we introduce various concepts of completeness of topologized semilattices in the context of operators that generalize the closure operator, and study their basic properties. In addition, examples of specific topologized semilattices are given, showing that these classes do not coincide with each other. Also in this paper, we prove theorems that allow us to generalize the available results on complete semilattices endowed with a topology. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.Ministry of Education and Science of the Russian Federation, MinobrnaukaThe work was performed as part of research conducted at the Ural Mathematical Center with the financial support of the Ministry of Science and Higher Education of the Russian Federation
A Multimodal Approach to Analgesia in Anorectal Surgery
Аim: Evaluation of methods for pain prevention and pain reduction after anorectal surgery at all stages of treatment based on publications found in available databases.Key points. Most anorectal diseases are benign and do not affect life expectancy, meanwhile about 40 % of the population suffer from it. Mainly anorectal disorders affect middle-aged people reducing their life quality. At the same time many articles aimed at studying only postoperative anesthesia. 2 researchers independently searched for articles published in Medline, Scopus, Cochrane, Web of Science, E-library databases using keywords. A total of 54 publications were included. A multimodal approach should include the pain prevention during pre-, intra- and postoperative periods. Acetaminophen is recommended for pain reduction according to the dosing protocols. Acetaminophen combined with other systemic analgesics is advisable for patients with severe pain. The opioids use is justified only for moderate-severe postoperative pain. Metronidazole and lidocaine with nitroglycerin ointment/ nifedipine/сorticosteroids effectiveness has been proven for local postoperative anesthesia. Prophylactic use of antibiotics and bowel preparation do not reduce postoperative pain. Stool softeners are recommended for reducing postoperative pain severity. Additional local anesthesia such as nerve blockade or infiltration anesthesia is recommended for all patients. Modern minimally invasive treatment methods of hemorrhoid are associated with less severe postoperative pain.Conclusion. The recommended scheme of multimodal anesthesia for patients after anorectal surgery is shown on Fig.1. Further studies are needed to evaluate preoperative anesthesia effectiveness, the feasibility of the perioperative flavonoids use, as well as comparisons of various minimally invasive treatment methods of anorectal diseases
Развитие и состояние микроэлектромеханических систем
В роботі проведений аналіз стану та розвитку мікроелектромеханічних систем (МЕМС), розглянуті технологічні процеси їх виготовлення та програмне забезпечення комп’ютерного моделювання МЕМС. Розглянуто існуючі мікропристрої, прилади та системи вимірювання параметрів руху, зокрема, прискорення, а також прилади орієнтації та навігації.In this paper the analysis of a condition and development of microelectromechanical systems (MEMS) is lead, technological processes of their manufacturing and the software of computer modulation MEMS are considered. Existing micro devices and systems of measurement of parameters of movement, in particular, acceleration, and also devices of orientation and navigation are considered.В работе проведен анализ состояния и развития микроэлектромеханических систем (МЕМС), рассмотрены технологические процессы их изготовления и программное обеспечение компьютерного модулирования МЕМС. Рассмотрены существующие микроустройства, приборы и системы измерения параметров движения, в частности, ускорения, а также приборы ориентации и навигации
Catalytic sulfation of betulin with sulfamic acid : experiment and DFT calculation
Betulin is an important triterpenoid substance isolated from birch bark, which, together with its sulfates, exhibits important bioactive properties. We report on a newly developed method of betulin sulfation with sulfamic acid in pyridine in the presence of an Amberlyst(®)15 solid acid catalyst. It has been shown that this catalyst remains stable when being repeatedly (up to four cycles) used and ensures obtaining of sulfated betulin with a sulfur content of ~10%. The introduction of the sulfate group into the betulin molecule has been proven by Fourier-transform infrared, ultraviolet-visible, and nuclear magnetic resonance spectroscopy. The Fourier-transform infrared (FTIR) spectra contain absorption bands at 1249 and 835–841 cm(−1); in the UV spectra, the peak intensity decreases; and, in the nuclear magnetic resonance (NMR) spectra, of betulin disulfate, carbons С3 and С28 are completely shifted to the weak-field region (to 88.21 and 67.32 ppm, respectively) with respect to betulin. Using the potentiometric titration method, the product of acidity constants K(1) and K(2) of a solution of the betulin disulfate H(+) form has been found to be 3.86 × 10(–6) ± 0.004. It has been demonstrated by the thermal analysis that betulin and the betulin disulfate sodium salt are stable at temperatures of up to 240 and 220 °C, respectively. The density functional theory method has been used to obtain data on the most stable conformations, molecular electrostatic potential, frontier molecular orbitals, and mulliken atomic charges of betulin and betulin disulfate and to calculate the spectral characteristics of initial and sulfated betulin, which agree well with the experimental data
Monitoring of tritium purity during long-term circulation in the KATRIN test experiment LOOPINO using laser Raman spectroscopy
The gas circulation loop LOOPINO has been set up and commissioned at Tritium
Laboratory Karlsruhe (TLK) to perform Raman measurements of circulating tritium
mixtures under conditions similar to the inner loop system of the neutrino-mass
experiment KATRIN, which is currently under construction. A custom-made
interface is used to connect the tritium containing measurement cell, located
inside a glove box, with the Raman setup standing on the outside. A tritium
sample (purity > 95%, 20 kPa total pressure) was circulated in LOOPINO for more
than three weeks with a total throughput of 770 g of tritium. Compositional
changes in the sample and the formation of tritiated and deuterated methanes
CT_(4-n)X_n (X=H,D; n=0,1) were observed. Both effects are caused by hydrogen
isotope exchange reactions and gas-wall interactions, due to tritium {\beta}
decay. A precision of 0.1% was achieved for the monitoring of the T_2
Q_1-branch, which fulfills the requirements for the KATRIN experiment and
demonstrates the feasibility of high-precision Raman measurements with tritium
inside a glove box
Structural and Mechanical Properties of DLC/TiN Coatings on Carbide for Wood-Cutting Applications
In this work, the diamond-like carbon and
titanium nitride (DLC/TiN) multilayer
coatings were prepared on a cemented
tungsten carbide substrate (WC—3 wt.%
Co) using the cathodic vacuum arc physical
vapor deposition (Arc-PVD) method and
pulsed Arc-PVD method with a graphite
cathode for the deposition of TiN and
carbon layers, respectively. The structural
and mechanical properties of the prepared
coatings were studied, and different
techniques, such as scanning electron
microscope (SEM), energy-dispersive X-ray
spectroscopy (EDX), X-ray diffraction
(XRD), Raman spectroscopy, and
microindentation techniques investigated
their microstructure, composition, and
phases. The prepared coatings had a
multilayer structure with distinct phases of
DLC, TiN, and carbide substrate. The
potentiodynamic polarization method
(PDP) was performed for the DLC/TiN
multilayer coatings in 3% NaCl solution to
evaluate the corrosion resistance of the
prepared coatings. It has been shown that
the DLC layer provided the coating with a
polarization resistance of 564.46 kΩ.
Moreover, it has been demonstrated that
the DLC/TiN coatings had a high hardness
of 38.7–40.4 GPa, which can help to
extend the wood-cutting tools’ life
THE POSSIBLE IMPACT OF L5 MAGNETOGRAMS ON NON-POTENTIAL SOLAR CORONAL MAGNETIC FIELD SIMULATIONS
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Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN.
We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (-1.0_{-1.1}^{+0.9}) eV^{2}. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation
Spatial Data Analysis Based on the Results of a Set of Observations of Deformation Processes Performed Using Strain Gauges
Данная статья посвящена вопросам наблюдения за деформациями конструкций уникальных объектов. В статье рассматривается анализ пространственных данных, полученных с использованием тензометрических датчиков, приведен расчет нагрузок, воспринимаемых конструкцией. Кроме того, приводится сопоставление тензометрических данных с величинами деформаций, полученными посредством геодезических методов.This article is devoted to the issues of observation and analysis of deformations of structures of unique objects. The article discusses the analysis of spatial data obtained using strain gauges, the calculation of loads perceived by the structure. In addition, the article presents a comparison of strain gauge data with the values of deformations obtained by geodetic methods
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