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The Torsind—A Device Based on a New Principle for Non-Conventional Astronomical Observations

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International Journal of Astronomy and Astrophysics 2013年第2期3卷 33-38页

作者： alexander f. Pugach Main Astronomical Observatory of National Academy of Sciences Kiev Ukraine

The description of a new device which is an improved version of the classic torsion balance is given. The device, which is the so-called “torsind”, seemed to be very sensitive to solar/lunar eclipses, and a Venus transit. It even responded to a solar eclipse when installed underground. The results of the most well-documented cases are described.

关键词： Solar Lunar Eclipses Venus Transit Torsion Balance Torsind

Novel Path Counting-Based Method for fractal Dimension Estimation of the Ultra-Dense Networks

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Intelligent Automation & Soft Computing 2023年第4期36卷 561-572页

作者： farid Nahli alexander Paramonov Naglaa f.Soliman Hussah Nasser AlEisa Reem Alkanhel Ammar Muthanna Abdelhamied A.Ateya Department of Telecommunication Networks and Data Transmission The Bonch-Bruevich Saint-Petersburg State University of TelecommunicationsSaint Petersburg193232Russia Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Computer Sciences College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh84428Saudi Arabia Department of Electronics and Communications Engineering Zagazig UniversityZagazig44519SharqiaEgypt

Next-generation networks,including the Internet of Things(IoT),ﬁfth-generation cellular systems(5G),and sixth-generation cellular systems(6G),suf-fer from the dramatic increase of the number of deployed *** puts high constraints and challenges on the design of such *** changing of the network is one of such challenges that affect the network performance,includ-ing the required quality of service(QoS).The fractal dimension(fD)is consid-ered one of the main indicators used to represent the structure of the communication *** this end,this work analyzes the fD of the network and its use for telecommunication networks investigation and *** clus-ter growing method for assessing the fD is introduced and *** article proposes a novel method for estimating the fD of a communication network,based on assessing the network’s connectivity,by searching for the shortest *** the cluster growing method,the proposed method does not require multiple iterations,which reduces the number of calculations,and increases the stability of the results ***,the proposed method requires less compu-tational cost than the cluster growing method and achieves higher *** method is quite simple to implement and can be used in the tasks of research and planning of modern and promising communication *** developed method is evaluated for two different network structures and compared with the cluster growing *** validate the developed method.

关键词： Cluster growing connectivity dense networks fractal dimension network structure shortest route quality of service

Managing esophagocutaneous fistula after secondary gastric pullup:A case report

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World Journal of Gastroenterology 2021年第16期27卷 1841-1846页

作者： Johan f Lock Stanislaus Reimer Sebastian Pietryga Rafael Jakubietz Sven flemming alexander Meining Christoph-Thomas Germer florian Seyfried Department of General VisceralTransplantationVascular and Pediatric SurgeryUniversity Hospital WürzburgWürzburg 97080Germany Department of Gastroenterology University Hospital WürzburgWürzburg 97080Germany Department of Trauma- Hand-Plastic-and Reconstructive SurgeryUniversity Hospital WürzburgWürzburg 97080Germany

BACKGROUND Gastric pull-up(GPU)procedures may be complicated by leaks,fistulas,or *** complications are usually managed by endoscopy,but in extreme cases multidisciplinary management including reoperation may be ***,we report a combined endoscopic and surgical approach to manage a failed secondary GPU *** SUMMARY A 70-year-old male with treatment-refractory cervical esophagocutaneous fistula with stenotic remnant esophagus after secondary GPU was transferred to our tertiary *** and systemic infection originating from the infected fistula was resolved by ***,elective esophageal reconstruction with freejejunal interposition was performed with no subsequent adverse *** A multidisciplinary approach involving interventional endoscopists and surgeons successfully managed severe complications arising from a cervical esophagocutaneous fistula after *** treatment may have lowered the perioperative risk to promote primary wound healing after free-jejunal graft interposition.

关键词： Esophageal fistula Gastric fistula Esophageal stenosis Esophageal perforation Endoscopic vacuum therapy free-jejunal graft Autogenous jejunum transplantation Case report

Symmetry Analysis of Barotropic Potential Vorticity Equation

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Communications in Theoretical Physics 2009年第10期52卷 697-700页

作者： alexander Bihlo RomanO.Popovych faculty of Mathematics University of Vienna Institute of Mathematics of NAS of Ukraine

Recently f. Huang [Commun. Theor. Phys. 42 （2004） 903] and X. Tang and P.K. Shukla [Commun. Theor. Phys. 49 （2008） 229] investigated symmetry properties of the barotropic potential vorticity equation without forcing and dissipation on the beta-plane. This equation is governed by two dimensionless parameters, f and β, representing the ratio of the characteristic length scale to the Rossby radius of deformation and the variation of earth＇ angular rotation, respectively. In the present paper it is shown that in the case f ≠ 0 there exists a well-defined point transformation to set β = 0. The classification of one- and two-dimensional Lie subalgebras of the Lie symmetry algebra of the potential vorticity equation is given for the parameter combination f ≠ 0 and β = 0. Based upon this classification, distinct classes of group-invariant solutions are obtained and extended to the case β ≠0.

关键词： potential vorticity equation Lie symmetries classification of subalgebras exact solutions

Turning up the NAD^(+)-mitophagy axis to treat Alzheimer's disease

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Neural Regeneration Research 2023年第2期18卷 319-319页

作者： Evandro f.fang alexander Anisimov Department of Clinical Molecular Biology University of Oslo and Akershus University HospitalLørenskogNorway The Norwegian Centre on Healthy Ageing(NO-Age) OsloNorway

The increase in the prevalence of individuals with Alzheimer's disease(AD)combined with the lack of a cure calls for the development of novel therapies against AD(Canter et al.,2016).The key disease-defining pathological features of AD are the accumulation of extracellular amyloid-beta(Aβ)plaques(accompanied by increasing intracellular Aβ_(1-42))and higher intracellular neu rofi brilla ry tangles,comprised mostly of hyperphosphorylated tau protein/pTau(Goedert,2015;Hardy,2017).It is evident that the elderly are more predisposed to develop AD,and thus aging is considered to be the primary risk factor for *** extra polation,strategies that delay aging may also slow down(if not stop)AD.

关键词： Alzheimer Aβ tau

facile Synthesis of Amino Acid Decorated Water-Soluble fullerene Derivatives with Anti-influenza Activity

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Chinese Journal of Chemistry 2023年第15期41卷 1803-1808页

作者： Valeriya S.Bolshakova Ekaterina O.Sinegubova Yana L.Esaulkova alexander S.Peregudov Ekaterina A.Khakina Nikita A.Slesarenko alexander f.Shestakov Vladimir V.Zarubaev Pavel A.Troshin Olga A.Kraevaya federal Research Center for Problems of Chemical Physics and Medicinal Chemistry of RAS Academician Semenov ave.1Chernogolovka142432Russia Higher Chemical College of RAS D.1.Mendeleev University of Chemical Technology of RussiaMiusskaya square 9Moscow125047Russia St.Petersburg Pasteur Institute Mira st.14St.Petersburg197101Russia A.N.Nesmeyanov Institute of Organoelement compounds of RAS Vavylova St.28B-334Moscow119991Russia National Research University Higher School of Economics Vavylova St.7Moscow101000Russia Department of fundamental Physics&Chemical Engineering M.V.Lomonosov Moscow State UniversityLeninskie Gory 1/51Moscow119991Russia Zhengzhou Research Institute Harbin Institute of TechnologyLongyuan East 7th 26Jinshui DistrictZhengzhouHenan 450003China Harbin Institute of Technology West Dazhi Street 92Nan Gang DistrictHarbinHeilongjiang 150001China

Comprehensive Summary Herein,we present a facile synthesis of amide-type water-soluble fullerene derivatives decorated with five residues of amino *** compared to the previously developed approaches,the proposed method enables usage of a broad range of amino acids,including those unstable under friedel-Crafts reaction ***,it is fully tolerant to the nature of the sixth addend X in C60R5X precursor compounds and allows one to obtain fullerene derivatives with X=Cl,H,*** synthesized amide-type water-soluble fullerene derivatives demonstrated promising antiviral activities against rimantadine-resistant influenzaА/Puerto Rico/8/34(Н1N1)virus in vitro.

关键词： fullerenes Amino acids Regioselectivity Water-solublel Influenza Antiviral

Targeting metabolic rewiring might decrease spread of tumor cells: Mitochondrial tRNA modifications promote cancer metastasis

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Signal Transduction and Targeted Therapy 2022年第11期7卷 3987-3988页

作者： Maik Luu alexander Visekruna Lehrstuhl für Zelluläre Immuntherapie Medizinische Klinik und Poliklinik IIUniversitätsklinikum WürzburgWürzburgGermany Institute for Medical Microbiology and Hygiene Philipps-UniversityMarburgGermany

In a recent study published in Nature,Delaunay and colleagues demonstrate that tRNA modifications in mitochondria have the potential to affect the synthesis of mitochondrial proteins involved in oxidative phosphorylation(OXPHOS),which drives the invasive spread of cancer *** inhibition of one particular RNA-modifying enzyme was sufficient to prevent the cancer cell invasion and dissemination.

关键词： invasion metastasis cancer

The Mg-carbonate-fe interaction:Implication for the fate of subducted carbonates and formation of diamond in the lower mantle

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Geoscience frontiers 2019年第4期10卷 1449-1458页

作者： Naira S.Martirosyan Konstantin D. Litasov Sergey S. Lobanov alexander f. Goncharov Anton Shatskiy Hiroaki Ohfuji Vitali Prakapenka Sobolev Institute of Geology and Mineralogy Russian Academy of ScienceKoptyuga ave.3Novosibirsk630090Russia Geophysical Laboratory Carnegie Institution for ScienceWashingtonDC20015USA Novosibirsk State University Pirogova st.2Novosibirsk630090Russia Geodynamic Research Center Ehime UniversityMatsuyamaEhime790-8577Japan Center for Advanced Radiation Sources University of ChicagoChicagoIL60637USA

The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil *** in situ synchrotro n X-ray diffraction and ex situ transmission electron microscopy we show that the reduction of Mg-carbonate can be exemplified by:6 MgCO3+19 fe=8 feO+10(Mg0.6fe^0.4)O+fe7 C3+3 *** presented results suggest that the interaction of carbonates with fe^0 or fe^0-bearing rocks can produce fe-carbide and diamond,which can accumulate in the D"region,depending on its carbon to fe *** to the sluggish kinetics of the transformation,diamond can remain metastable at the core-mantle boundary(CMB)unless it is in a direct contact with *** addition,it can be remobilized by redox melting accompanying the generation of mantle plumes.

关键词： Deep carbon cycle Carbonate Carbide High pressure Redox reaction

An investigation of flare emissions at multiple wavelengths

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Research in Astronomy and Astrophysics 2021年第3期21卷 149-157页

作者： Dong Li alexander Warmuth Lei Lu Zongjun Ning Key Laboratory for Dark Matter and Space Science Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210033China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China Leibniz-Institut für Astrophysik Potsdam(AIP) An der Sternwarte 1614482 PotsdamGermany School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

We report multi-wavelength observations of four solar flares on 2014 July *** firstly select these flares according to the soft X-ray(SXR)and extreme ultraviolet(EUV)emissions recorded by the Extreme Ultraviolet Variability Experiment and Geostationary Orbiting Environmental S *** their locations and geometries are identified from the full-disk images measured by the Atmospheric Imaging Assembly(AIA),and the time delays among the light curves in different channels are *** electron number densities are estimated using the differential emission measure *** find that three of four flares show strong emissions in SXR channels and high temperature(>6 MK)EUV wavelengths during the impulsive phase,i.e.,AIA 131 A and 94 A,and then they emit peak radiation subsequently in the middle temperature(~0.6-3 MK)EUV ***,they last for a long time and have smaller electron densities,which are probably driven by the interaction of hot diffuse flare *** one flare emits radiation at almost the same time in all the observed wavelengths,lasts for a relatively short time,and has a larger electron *** is also accompanied by a typeⅢradio *** bright emission at the EUV channel could be corresponding to the associated erupting filament.

关键词： Sun:flares Sun:radio radiation Sun:UV radiation Sun:X-rays,gamma rays