A new approach to hetaryl carbamates through a tandem condensation/rearrangement reaction of 2‐aminohetarene N‐oxides was developed. The developed reaction is suitable for both five‐ and six‐membered ...heterocycles and proceeds through the condensation of 2‐aminohetarene N‐oxide with trimethyl orthoformate followed by intramolecular N‐oxide oxygen transfer. For five‐membered hetarene N‐oxides (furoxans), the intramolecular rearrangement is catalyzed by a cyanide anion, while for six‐membered hetarene N‐oxides (azines), Lewis acid catalysis is sufficient. The developed protocol is characterized by operational simplicity and high efficiency, resulting in carbamoyl derivatives in good and high yields.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
•Due to the COVID pandemic, health care–associated infection rates increased in resource-limited countries.•Due to the COVID pandemic, rates of central line–associated bloodstream infections ...increased.•Due to the COVID pandemic, rates of central ventilator–associated events increased.•Due to the COVID pandemic, mortality rates increased in intensive care units of resource-limited countries in 2020.•Due to the COVID pandemic, average length of stay increased in resource-limited countries in 2020.
This study examines the impact of the COVID-19 pandemic on health care–associated infection (HAI) incidence in low- and middle-income countries (LMICs).
Patients from 7 LMICs were followed up during hospital intensive care unit (ICU) stays from January 2019 to May 2020. HAI rates were calculated using the International Nosocomial Infection Control Consortium (INICC) Surveillance Online System applying the Centers for Disease Control and Prevention's National Healthcare Safety Network (CDC-NHSN) criteria. Pre–COVID-19 rates for 2019 were compared with COVID-19 era rates for 2020 for central line–associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTIs), ventilator-associated events (VAEs), mortality, and length of stay (LOS).
A total of 7,775 patients were followed up for 49,506 bed days. The 2019 to 2020 rate comparisons were 2.54 and 4.73 CLABSIs per 1,000 central line days (risk ratio RR = 1.85, p = .0006), 9.71 and 12.58 VAEs per 1,000 mechanical ventilator days (RR = 1.29, p = .10), and 1.64 and 1.43 CAUTIs per 1,000 urinary catheter days (RR = 1.14; p = .69). Mortality rates were 15.2% and 23.2% for 2019 and 2020 (RR = 1.42; p < .0001), respectively. Mean LOS for 2019 and 2020 were 6.02 and 7.54 days (RR = 1.21, p < .0001), respectively.
This study documents an increase in HAI rates in 7 LMICs during the first 5 months of the COVID-19 pandemic and highlights the need to reprioritize and return to conventional infection prevention practices.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The results of numerical simulation of gas-dynamic flow in the channel of a technical device with a resonant cavity are presented. One period of gas-dynamic loading of structural elements of the ...resonant cavity has been studied in detail. A complete picture of pressure and temperature field distribution along the resonant cavity channel has been obtained. The maximum and minimum values of pressure and temperature, achieved when the gas flow moves along the resonator channel, have been determined.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OILJ, PNG, SAZU, SBCE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
With using the mechanics of multiphase media, the process of extraction of moisture from a dead pore is considered. The study was carried out by numerical simulation. Two-dimensional ...approach of interaction of the air flow with droplets without taking into account the processes of heat and mass transfer was considered.
This paper is a continuation of a series of papers devoted to the numerical solution of integral equations using local interpolation splines. The main focus is given to the use of splines of the ...fourth order of approximation. The features of the application of the polynomial and non-polynomial splines of the fourth order of approximation to the solution of Volterra integral equation of the second kind are discussed. In addition to local splines of the Lagrangian type, integro-differential splines are also used to construct computational schemes. The comparison of the solutions obtained by different methods is carried out. The results of the numerical experiments are presented.
Complex transition‐metal oxides exhibit a wide variety of chemical and physical properties which are a strong function the local electronic states of the transition‐metal centres, as determined by a ...combination of metal oxidation state and local coordination environment. Topochemical reduction of the double perovskite oxide, LaSrCoRuO6, using Zr, yields LaSrCoRuO5. This reduced phase contains an ordered array of apex‐linked square‐based pyramidal Ru3+O5, square‐planar Co1+O4 and octahedral Co3+O6 units, consistent with the coordination‐geometry driven disproportionation of Co2+. Coordination‐geometry driven disproportionation of d7 transition‐metal cations (e.g. Rh2+, Pd3+, Pt3+) is common in complex oxides containing 4d and 5d metals. However, the weak ligand field experienced by a 3d transition‐metal such as cobalt leads to the expectation that d7+ Co2+ should be stable to disproportionation in oxide environments, so the presence of Co1+O4 and Co3+O6 units in LaSrCoRuO5 is surprising. Low‐temperature measurements indicate LaSrCoRuO5 adopts a ferromagnetically ordered state below 120 K due to couplings between S=1/2 Ru3+ and S=1 Co1+.
Topochemical reduction of LaSrCoRuO6 yields LaSrCoRuO5 a phase containing Co3+O6, Co1+O4 and Ru3+O5 units, consistent with the coordination‐geometry‐driven disproportionation of Co2+ in an extended oxide.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Transparent glass-ceramics of magnesium aluminosilicate system based on Fe2+:MgAl2O4 spinel nanocrystals nucleated by a mixture of TiO2 and ZrO2 and doped with 0.6 mol% FeO were developed. The glass ...was melted at 1580 °C with stirring and heat-treated in the temperature range from 800 to 1300 °C. The structure and spectroscopic properties of the glass and glass-ceramics were studied by DSC and XRD methods, Raman and absorption spectroscopy. ZrTiO4 nanocrystals 6 nm in size precipitate during the nucleation heat-treatment at 800 °C. Spinel nanocrystals 9-14 nm in size are formed during heat-treatments at 850- 1000 °C. Intense absorption at ~2 μm is observed due to Fe2+ ions in tetrahedral positions in these crystals. Iron-doped sapphirine crystallization in transparent glass-ceramics at 1000-1050 °C results in a decrease of absorption in this spectral range. The glass-ceramics are important for the development of saturable absorbers for the spectral range of 2-3 μm.
•Microglial activity was studied using different assays, e.g., immunohistochemistry, transcriptomics, and flow cytometry.•Opioid tolerance and hyperalgesia associate with glial activation in the ...spinal cord but not in the brain.•The spinal microglia transcriptome suggests that morphine-induced glial activation resembles that of traumatic neuropathy.
Development of tolerance is a well known pharmacological characteristic of opioids and a major clinical problem. In addition to the known neuronal mechanisms of opioid tolerance, activation of glia has emerged as a potentially significant new mechanism. We studied activation of microglia and astrocytes in morphine tolerance and opioid-induced hyperalgesia in rats using immunohistochemistry, flow cytometry and RNA sequencing in spinal- and supraspinal regions. Chronic morphine treatment that induced tolerance and hyperalgesia also increased immunoreactivity of spinal microglia in the dorsal and ventral horns. Flow cytometry demonstrated that morphine treatment increased the proportion of M2-polarized spinal microglia, but failed to impact the number or the proportion of M1-polarized microglia. In the transcriptome of microglial cells isolated from the spinal cord (SC), morphine treatment increased transcripts related to cell activation and defense response. In the studied brain regions, no activation of microglia or astrocytes was detected by immunohistochemistry, except for a decrease in the number of microglial cells in the substantia nigra. In flow cytometry, morphine caused a decrease in the number of microglial cells in the medulla, but otherwise no change was detected for the count or the proportion of M1- and M2-polarized microglia in the medulla or sensory cortex. No evidence for the activation of glia in the brain was seen. Our results suggest that glial activation associated with opioid tolerance and opioid-induced hyperalgesia occurs mainly at the spinal level. The transcriptome data suggest that the microglial activation pattern after chronic morphine treatment has similarities with that of neuropathic pain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
This paperwork presents the results of a series of experiments on the use of homogenizing annealing, aimed at the possibility to control the structure and properties of steel samples obtained by ...aluminothermy. This method of processing, in some cases, allows to eliminate the need to use subsequent heat treatment operations due to the achievement of the required properties by the cast blank material. Refractory materials and thermite mixtures used, conditions for the production of castings and their total chemical composition are given. The tensile diagram analysis of the samples before and after heat treatment is presented; the structures and diffraction patterns of the samples’ destruction spots are considered. The material obtained by aluminothermy corresponds in its chemical composition to A1, A2, A3, A4 grade of steels for the rail transport according to GOST 31334-2007 which are used in the manufacture of locomotive axes and other rolling stock.
The paper presents the results of a morphometric study of the internal organs of a water deer (
Hydropotes inermis
Swinhoe 1870) found in the southern part of the Primorsky Krai of Russia. For the ...first time, the linear and weight parameters were determined, the morphological features of the internal organs of the water deer were described.
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