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An overview of the anti-SARS-CoV-2 properties of Artemisia annua, its antiviral action, protein-associated mechanisms, and repurposing for COVId-19 treatment

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Journal of Integrative Medicine 2021年第5期19卷 375-388页

作者： Andrea d.Fuzimoto Holistic Sync-Holistic Integrative Medicine USA/Brazil

Artemisia annua and its phytocompounds have a rich history in the research and treatment of malaria,rheumatoid arthritis, systemic lupus erythematosus, and other diseases. Currently, the World Health Organization recommends artemisinin-based combination therapy as the first-line treatment for multi-drug-resistant malaria. due to the various research articles on the use of antimalarial drugs to treat coronaviruses, a question is raised: would A. annua and its compounds provide anti-severe acute respiratory syndrome coronavirus-2(SARS-CoV-2) properties? PubMed/MEdLINE, Scopus, and Google Scholar were searched for peer-reviewed articles that investigated the antiviral effects and mechanisms of A. annua and its phytochemicals against SARS-CoVs. Particularly, articles that evidenced the herb’s role in inhibiting the coronavirus-host proteins were favored. Nineteen studies were retrieved. From these,fourteen in silico molecular docking studies demonstrated potential inhibitory properties of artemisinins against coronavirus-host proteins including 3 CL^(PRO), S protein, N protein, E protein, cathepsin-L, helicase protein, nonstructural protein 3(nsp3), nsp10, nsp14, nsp15, and glucose-regulated protein 78 ***, A. annua constituents may impede the SARS-CoV-2 attachment, membrane fusion, internalization into the host cells, and hinder the viral replication and transcription process. This is the first comprehensive overview of the application of compounds from A. annua against SARS-CoV-2/coronavirus disease 2019(COVId-19) describing all target proteins. A. annua’s biological properties, the signaling pathways implicated in the COVId-19, and the advantages and disadvantages for repurposing A. annua compounds are discussed. The combination of A. annua’s biological properties, action on different signaling pathways and target proteins, and a multi-drug combined-therapy approach may synergistically inhibit SARS-CoV-2 and assist in the COVId-19 treatment. Also, A

关键词： COVId-19 SARS-CoV-2 Artemisia annua Artemisinin Main protease Spike protein

Light controlled imaging probes for intracellular target recognition： photochromism as a tool to enhance sensing precision

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Science China Chemistry 2017年第12期60卷 1563-1564页

作者： Tony d. James department of Chemistry University of BathBath BA2 7AYUK

Chemosensors and imaging probes have been the focus of significant research interest over the past few decades. In part due to ease of preparation and simplicity in manipulation, fluorescent probes have been extensive... 详细信息

关键词： Light controlled imaging probes for intracellular target recognition photochromism enhance sensing precision

Effect of Y_2O_3 and Total Oxide Addition on Mechanical Properties of Pressureless Sintered β-SiC

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Journal of Materials Science & Technology 2003年第3期19卷 193-196页

作者： Vladimir d.Krstic Centre for Manufacturing of Advanced Ceramics and Nanomaterials Queen’s UniversityNicol HallKingstonOntarioCanada K7L 3N6

The effect of Y203 and the total oxide volume fraction (Y203+AI203) on density and mechanical properties of low temperature (1770-1940℃) pressureless sintered β-SiC ceramics were presented. The optimum temperature for pressureless sintering of β-SiC was found to be -1850℃ and the optimum content of Y203 in the oxides was found to be between 40 and 57 wt pct. The highest sintered density was achieved by adding oxides at 14 vol. pct. Both of the highest strength and fracture toughness were achieved at -14 vol. pct oxide addition and yttria concentrations between 40 and 57 wt pct in the oxides. Hardness, on the other hand, was found to be the highest for samples with 14 vol. pct oxide addition and -64 wt pct Y2O3 in oxides.

关键词： Y_2O_3 SiC Mechanical properties Sintering

Ground and flight tests of AlSat-1B butane propulsion system

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Propulsion and Power Research 2022年第1期11卷 74-84页

作者： d.darfilala d.Gibbon Satellite development Center CdS Algerian Space Agency ASALBP 4065Ibn Rochd USTOOran31130Algeria Surrey Satellite Technology Ltd. GuildfordSurrey GU27YEUnited Kingdom

On September 26,2016 Algerian Space Agency launched AlSat-1B,the second in a series of medium resolution earth observation satellites ***-1B electro-thermal propulsion system follows the classic design principle that has been used on previous SSTL-100 *** a total dry weight of 5.17 kg,the system is filled with 2.35 L selfpressurized *** thruster assembly is designed to use 15 W(at 28 V)redundant heater elements,it is designed to have an average mission thrust of 50 *** a warm up time of 10 min,the temperature of the butane will be increased by over 250℃.This is the equivalent of about 35%gain in specific impulse over ambient temperature *** spacecraft dry weigh at launch site was 107 kg,the propulsion system is designed to provide at least 19 m/s delta-v to meet the spacecraft’s mission *** investigate the system readiness for flight,a series of performance tests have been completed at the Surrey Satellite Technology Ltd laboratories(United Kingdom),Satellite development Centre(Algeria)and Satish dhawan Space Centre rocket launch site(India),the results of these tests as well as initial flight test results are presented in this paper.

关键词： Space Propulsion Butane Resistojet Heaters Specific impulse

A　Possible　Origin　of　dark　Energy

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Chinese Physics Letters 2004年第6期21卷 1187-1188页

作者： T.d.Lee Physicsdepartment ColumbiaUniversityNewYorkNY10027USA

We discuss the possibility that the existence of dark energy may be due to the presence of a spin zero field φ(x), either elementary or composite. In the presence of other matter field, the transformation φ(x)→φ(x) + constant can generate a negative pressure, like the cosmological constant. In this picture, our universe can be thought as a very large bag, similar to the much smaller MIT bag model for a single nucleon.

关键词： Gravitation and cosmology Particle physics and field theory Astrophysics and astroparticles

FLOW OF MICROPOLAR FLUId THROUGH CATHETERIZEd ARTERY -- A MATHEMATICAL MOdEL

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International Journal of Biomathematics 2012年第2期5卷 61-72页

作者： d.SRINIVASACHARYA d.SRIKANTH department of Mathematics National Institute of Technology Warangal-506004 Andhra PradeshIndia department of Applied Mathematicsdefence Institute of Advanced Technology Pune-~11025 India

In this paper, the flow of blood through catheterized artery with mild constriction at the outer wall is considered. The closed form solutions are obtained for velocity and microrotation components. The impedance （resistance to the flow） and wall shear stress are calculated. The effects of catheterization, coupling number, micropolar parameter, and height of the stenosis on impedance and wall shear stresses are discussed.

关键词： Stenosis catheter micropolar fluid impedance wall shear stress.

Frequency Switches at Transition Temperature in Voltage-Gated Ion Channel dynamics of Neural Oscillators

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Chinese Physics Letters 2018年第5期35卷 152-155页

作者： Yasuomi d.Sato department of System Information Sciences Graduate School of Information Sciences Tohoku University Institute of Industrial Science University of Tokyo

Understanding of the mechanisms of neural phase transitions is crucial for clarifying cognitive processes in the brain. We investigate a neural oscillator that undergoes different bifurcation transitions from the big saddle homoclinic orbit type to the saddle node on an invariant circle type, and the saddle node on an invariant circle type to the small saddle homoclinic orbit type. The bifurcation transitions are accompanied by an increase in thermodynamic temperature that affects the voltage-gated ion channel in the neural oscillator. We show that nonlinear and thermodynamical mechanisms are responsible for different switches of the frequency in the neural oscillator. We report a dynamical role of the phase response curve in switches of the frequency, in terms of slopes of frequency-temperature curve at each bifurcation transition. Adopting the transition state theory of voltagegated ion channel dynamics, we confirm that switches of the frequency occur in the first-order phase transition temperature states and exhibit different features of their potential energy derivatives in the ion channel. Each bifurcation transition also creates a discontinuity in the Arrhenius plot used to compute the time constant of the ion channel.

关键词： Frequency Switches at Transition Temperature in Voltage-Gated Ion Channel dynamics of Neural Oscillators

Changes in Repetitive Firing Rate Related to Phase Response Curves for Andronov-Hopf Bifurcations

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Chinese Physics Letters 2014年第5期31卷 13-16页

作者： Yasuomi d. Sato department of Brain Science and Engineering Graduate School of Life Science and Systems Engineering Kyushu Institute of Technology 2-4 Hibikino Wakamatsu Kitakyushu 808-0196 Japan Frankfurt Institute for Advanced Studies (FIAS) Johann Wolfgang Goethe University Ruth-Moufang-Str.1 D60438 Frankfurt am Main Germany Institute of Industrial Science the University of Tokyo 4-6-1 Komaba Meguro Tokyo 153-8505 Japan

We study specific changes in repetitive firing in the two-dimensional Hindmarsh-Rose （2dHR） oscillatory sys- tem that undergoes a bifurcation transition from the supercritical Andronov-Hopf （All） type to the subcritical Andronov-Hopf （SAH） type. We identify dynamical mechanisms which are responsible for changes of the repeti- tive firing rate during the AH to SAH bifurcation transitions. These include frequency-shift functions in response to small perturbations of a timescale parameter, its multiplicative parameter, and an external input current in the 2dHR oscillatory system. The frequency-shift functions are explicitly represented as functions relating to the phase response curves （PRCs）. Then, we demonstrate that when the timescale is normal and relatively fast, the repetitive firing rate slightly increases and decreases respectively during the AH to SAH bifurcation transition with a change of the intrinsic parameter, whereas it decreases during the SAH to AH bifurcation transition with an increase in the timescale. By analyzing the three different frequency-shift functions, we show that such changes of the repetitive firing rate depend largely on changes of the PRC size. The PRC size for the SAH bifurcation shrinks to the PRC size for the AH bifurcation.

关键词： HOPF bifurcations FREQUENCY shift keying MONOTONIC functions VAN der Pol oscillators (Physics) LIMIT cycles

dirac Points in Two-dimensional Inverse Opals

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Chinese Physics Letters 2013年第10期30卷 164-166页

作者： G.d.Mahan department of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA

The electron energy states and energy bands are calculated for a two-dimensional inverse opal *** that the opal structure is closed-packed circles,the inverse opal has the honeycomb *** honeycomb lattice in two dimensions has a diract *** properties can be manipulated by altering the structure of the inverse opal:the radius of the circle,and the small gap between circles.

关键词： structure inverse dirac