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Low-Energy Driven Ring-Opening Behavior of Benzocyclobutene Derivatives

Chinese Journal of Chemistry 2023年第23期41卷 3238-3244页

作者： Ziwei Yuan Quan Sun Jinchong Xiao Pingxia Zhang konstantin S.Levchenko Dmitry Y.Demin Wenxin Fu Laboratory of Science and Technology on High-Tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing100190 China College of Chemistry and Material Science Hebei UniversityBaodingHebei071002 China University of Chinese Academy of Sciences Beijing100049 China MIREA — Russian Technological University Moscow119454 Russian Federation

It's urgent to develop benzocyclobutene(BCB)-based polymers with low curing temperature for temperature-sensitive applications such as liquid crystal displays(LCDs)and flexible ***,the effect of substituents on the ring-opening behavior of BCB derivatives was *** ring-opening activation energy barriers(ΔGA)of BCB derivatives with one or two substituents on the four-membered alkyl ring were systematically calculated using the B3LYP *** mono-and di-substituted BCBs adopted the conrotatory ring-opening process,obeying the Woodward-Hoffmann's Rules upon *** mono-/di-substituted BCBs exhibited 8.2%—69%lowerΔGA compared with BCB,attributed to the electronic effects of the *** BCBs with both electron-donating and electron-withdrawing groups,e.g.,1-NH_(2)-8-NO_(2)-BCB,demonstrated the lowestΔ*** addition,BCB derivatives with amide/ester/acyloxy group modified on C1 position were synthesized as model molecules,and their ring-opening temperature can be decreased by 20℃ compared to the unsubstituted one,also consistent with our calculation *** work combined theoretical calculation methods with experimental results to provide valuable insights into the design and synthesis of BCB derivatives and next-generation BCB functional packaging materials with low ring-opening temperature.

关键词： Benzocyclobutene Thermosets Monomers Low curing temperature Activation energy barrier Electronic effect Captodative effect

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Chemical Mechanisms of Prebiotic Chirality Amplification

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Research 2020年第1期2020卷 914-921页

作者： konstantin P.Bryliakov Novosibirsk State University Pirogova 1Novosibirsk 630090Russia Boreskov Institute of Catalysis Pr.Lavrentieva 5Novosibirsk 630090Russia

This review article surveys the recent experimental findings that suggest alternative chemical models of directed chirality amplification at the early,prebiotic *** is believed that the chirality amplification step followed the initial emergence of small enantiomeric imbalance and preceded(as a necessary condition)the occurrence of homochiral biopolymers,assembled from enantiomerically pure building *** work focuses on the chemical nature of possible mechanisms of primordial chirality enhancement,without going into detail of the preceding and subsequent phases of origination of biological homochirality and life on *** mechanisms are discussed through the prism of integrity of biological natural selection and chemical kinetic selection.

关键词： Chiral subsequent finding

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Mathematical modelling of the progression of active tuberculosis:Insights from fluorography data

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Infectious Disease Modelling 2022年第3期7卷 374-386页

作者： konstantin konstantinovich Avilov Alexei Alexeevich Romanyukha Evgeny Mikhailovich Belilovsky Sergey Evgenevich Borisov Institute for Numerical Mathematics Russian Academy of Sciences8Gubkina Str.Moscow119333Russia Moscow Research and Clinical Center for Tuberculosis Control of the Moscow Government Department of Health 10Stromynka Str.Moscow107076Russia

Little is known about the dynamics of the early stages of untreated active pulmonary tuberculosis:unknown are both the rates of progression and the model“scheme”.The“parallel”scheme assumes that infectiousness of tuberculosis cases is effectively predefined at the onset of the disease,and the“serial”scheme considers all cases to be noninfectious at the onset,with some of them later becoming *** aim was to estimate the progression of the early stages of pulmonary tuberculosis using data from a present-day *** used the routine notification data from Moscow,Russia,2013e2018 that contained the results and time of the last fluorographic screening preceding the detection of tuberculosis *** provided time limits on the duration of untreated *** of TB progression under both models were *** the goodness of fit to the data,we could prefer neither the“parallel”,nor the“serial”model,although the latter had a bit worse *** the other hand,the observed rise in the fraction of infectious tuberculosis cases with the time since the last screening was explained by the“serial”model in a more plausible way e as gradual progression of some cases to ***“parallel”model explained it through less realistic quick removal of non-infectious cases and accumulation of the infectious *** results demonstrate the potential of using such detection data enriched with reassessments of the previous screenings.

关键词： Natural history of tuberculosis(TB) Mathematical modeling Minimal tuberculosis Model structure Fluorographic screening data

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World Journal of Gastroenterology 2010年第40期16卷 5024-5034页

作者： konstantin Umanskiy Alessandro Fichera Department of Surgery University of Chicago Medical Center

Over the past 30 years, health related quality of life (HRQOL) has developed into a scientific index of subjective health status. Measurement of HRQOL is now clearly a mandatory component in evaluating interventions and management of medical and surgical diseases. In designing comprehensive and meaningful clinical studies particular attention ought to be made of measures of HRQOL. This is clearly very important in inflammatory bowel disease. Both ulcerative colitis (UC) and Crohn’s disease (CD) have a major impact on HRQOL. The chronic and unrelenting nature of these diseases, the often early age of onset, and the impact on social and sexual aspects of life significantly change patient’s perception, body image and quality of life. This manuscript is an overview of the available published data on HRQOL in UC and CD patients focusing on the impact of surgical therapy. While these two diseases may have some similarities in their management, clearly their impact on quality of life and the effects of are significantly different. Hence we are presenting the data separately.

关键词： Inflammatory bowel disease Quality of life Gastrointestinal surgery Surgical outcome

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Fiber laser with random-access pulse train profiling for a photoinjector driver

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Photonics Research 2017年第4期5卷 293-298页

作者： EKATERINA I.GACHEVA ANATOLY K.POTEOMKIN SERGEY YU.mironov VIKTOR V.ZELENOGORSKII EFIM A.KHAZANOV konstantin B.YUSHKOV ALEXANDER I.CHIZHIKOV VLADIMIR YA.MOLCHANOV Institute of Applied Physics of the Russian Academy of Sciences (IAP RAS) National University of Science and Technology "MISIS "

We report on the design and performance of a fiber laser system with adaptive acousto-optic macropulse control for a novel photocathode laser driver with 3D ellipsoidal pulse shaping. The laser system incorporates a threestage fiber amplifier with an integrated acousto-optical modulator. A digital electronic control system with feedback combines the functions of the arbitrary micropulse selection and modulation resulting in macropulse envelope profiling. As a benefit, a narrow temporal transparency window of the modulator, comparable to a laser pulse repetition period, effectively improves temporal contrast. In experiments, we demonstrated rectangular laser pulse train profiling at the output of a three-cascade Yb-doped fiber amplifier.

关键词： AOM Fiber laser with random-access pulse train profiling for a photoinjector driver

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Hepatobiliary system and intestinal injury in new coronavirus infection(COVID-19):A retrospective study

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World Journal of Clinical Cases 2023年第10期11卷 2226-2236页

作者： konstantin V Kozlov konstantin V Zhdanov Anna K Ratnikova Vyacheslav A Ratnikov Artem V Tishkov Vladimir Grinevich Yuriy A Kravchuk Panteley I Miklush Polina O Nikiforova Vera V Gordienko Alexander F Popov Boris G Andryukov Department of Infectious Disease Military Medical Academy Named After SM.KirovSaint-Petersburg 194044Russia Department of Admission Federal State Budgetary Institution"North-West District Scientific and Clinical Center Named After LG.Sokolov Federal Medical and Biological Agency"Saint-Petersburg 194291Russia Department of Roentgenology Federal State Budgetary Institution"North-West District Scientific and Clinical Center Named After LG.Sokolov Federal Medical and Biological Agency"Saint-Petersburg 194291Russia Department of Physics Mathematics and InformaticsFSBEI HE IP.Pavlov SPbSMU MOH RussiaSaint-Petersburg 197022Russia 2nd Department of Therapy(Advanced Medical Education) Military Medical Academy Named After SM.KirovSaint-Petersburg 194044Russia School of Medicine Far Eastern Federal UniversityVladivostok 690922Russia

BACKGROUND An important area of effective control of the coronavirus disease 19(COVID-19)pandemic is the study of the pathogenic features of severe acute respiratory syndrome coronavirus 2 infection,including those based on assessing the state of the intestinal microbiota and *** To study the clinical features of the new COVID-19 in patients with mild and moderate severity at the stage of hospitalization,to determine the role of hepatobiliary injury,intestinal permeability disorders,and changes in the qualitative and quantitative composition of the microbiota in the development of systemic inflammation in patients with *** The study was performed in 80 patients with COVID-19,with an average age of 45 years,19 of whom had mild disease,and 61 had moderate disease *** scope of the examination included traditional clinical,laboratory,biochemical,instrumental,and radiation studies,as well as original methods for studying microbiota and intestinal *** The clinical course of COVID-19 was studied,and the clinical and biochemical features,manifestations of systemic inflammation,and intestinal microbiome changes in patients with mild and moderate severity were *** permeability characteristics against the background of COVID-19 were evaluated by measuring levels of proinflammatory cytokines,insulin,faecal calprotectin,and *** This study highlights the role of intestinal permeability and microbiota as the main drivers of gastroenterological manifestations and increased COVID-19 severity.

关键词： Novel coronavirus infection COVID-19 SARS-CoV-2 Zonulin Faecal calprotectin Microbiota

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Experimental and ab initio study of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F stability in the pressure range of 0–10 GPa

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International Journal of Minerals,Metallurgy and Materials 2023年第9期30卷 1846-1854页

作者： Nursultan E.Sagatov Tatyana B.Bekker Yulia G.Vinogradova Alexey V.Davydov Ivan V.Podborodnikov konstantin D.Litasov Sobolev Institute of Geology and Mineralogy Siberian Branch of Russian Academy of SciencesNovosibirsk 630090Russia Department of Geology and Geophysics Novosibirsk State UniversityNovosibirsk 630090Russia Research and Development Department Novosibirsk State University of ArchitectureDesign and Arts(NSUADA)Novosibirsk 630099Russia Vereshchagin Institute for High Pressure Physics Russian Academy of SciencesTroitsk 108840Russia Fersman Mineralogical Museum Russian Academy of SciencesMoscow 119071Russia

Both numerical and experimental studies of the stability and electronic properties of barium–sodium metaborate Ba_(2)Na_(3)(B_(3)O_(6))_(2)F(P63/m) at pressures up to 10 GPa have been carried out. Electronic-structure calculations with HSE06 hybrid functional showed that Ba_(2)Na_(3)(B_(3)O_(6))_(2)F has an indirect band gap of 6.289 eV. A numerical study revealed the decomposition of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F into the BaB_(2)O_(4),Na BO_(2), and NaF phases above 3.4 GPa at 300 K. Subsequent high-pressure high-temperature experiments performed using ‘Discoverer-1500’DIA-type apparatus at pressures of 3 and 6 GPa and temperature of 1173 K confirmed the stability of Ba_(2)Na_(3)(B_(3)O_(6))_(2)F at 3 GPa and its decomposition into BaB_(2)O_(4), NaBO_(2), and NaF at 6 GPa, which was verified by energy-dispersive X-ray analysis and Raman spectroscopy. The observed Raman bands of the Ba_(2)Na_(3)(B_(3)O_(6))_(2)F phase were assigned by comparing the experimental and calculated spectra. The experimental Raman spectra of decomposition reaction products obtained at 6 GPa suggest the origin of a new high-pressure modification of barium metaborate BaB_(2)O_(4).

关键词： density functional theory phase stability borate high pressure Raman spectroscopy

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Atomic scale memristive photon source

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Light(Science & Applications) 2022年第7期11卷 1414-1422页

作者： Bojun Cheng Till Zellweger konstantin Malchow Xinzhi Zhang Mila Lewerenz Elias Passerini Jan Aeschlimann Ueli Koch Mathieu Luisier Alexandros Emboras Alexandre Bouhelier Juerg Leuthold ETH Zurich Institute of Electromagnetic FieldsZurich 8092Switzerland Laboratoire Interdisciplinaire Carnot de Bourgogne UMR 6303 CNRSUniversitéde Bourgogne Franche-ComtéDijon 21078France ETH Zurich Integrated Systems LaboratoryZurich 8092Switzerland

Memristive devices are an emerging new type of devices operating at the scale of a few or even single *** are currently used as storage elements and are investigated for performing in-memory and neuromorphic *** these devices,Ag/amorphous-SiO_(x)/Pt memristors are among the most studied systems,with the electrically induced filament growth and dynamics being thoroughly investigated both theoretically and *** this paper,we report the observation of a novel feature in these devices:The appearance of new photoluminescent centers in SiO_(x) upon memristive switching,and photon emission correlated with the conductance *** observation might pave the way towards an intrinsically memristive atomic scale light source with applications in neural networks,optical interconnects,and quantum communication.

关键词： photon thoroughly amorphous

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Restoration of function after cortical lesion: does it require an internal template?

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Neural Regeneration Research 2014年第23期9卷 2029-2031页

作者： Holger Schulze konstantin Tziridis Experimental Otolaryngology Friedrich-Alexander University Erlangen-Nürnberg

The brain controls virtually all body functions, both internally and in interaction with the external environment. As the basic body anatomy of all vertebrates has a bilateral symmetry, structures and functions of vertebrate brains are also organized according to this fundamental anatomical principle to meet all sensory, motor, and internal requirements of body control. Consequently, particular parts or functions of the body are controlled by particular brain structures.

关键词： does it require an internal template

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Taxonomic Composition and Spatial Distribution of Meiofauna Community from a Sandy Intertidal Zone in Sishili Bay, Yellow Sea Coast (Northern China)

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Journal of Ocean University of China 2022年第5期21卷 1389-1401页

作者： PAVLYUK Olga N TREBUKHOVA Yulia A SHCHERBAKOV Ilya A TARASOVA Tatiana S LUTAENKO konstantin A CHEN Linlin SONG Bo LI Xiaojing LI Baoquan A.V.Zhirmunsky National Scientific Center of Marine Biology Far Eastern BranchRussian Academy of SciencesVladivostok 690041Russia Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264003China

The meiofauna composition and trophic groups of the nematode communities have been studied at a sandy intertidal zone in Sishili Bay along the Yantai coast(Yellow Sea,China).Nematoda was dominant among the 11 groups of *** meiofaunal densities were low,ranging between 111±47 and 542±131 ind./10 cm^(2).Results obtained from the correlation analysis made it possible to determine several factors that influence species composition and ***,sediment granulometry significantly affected the *** highest abundance was found in fine-grained sediments(318.77±126 ind./10 cm^(2))com-pared to coarse-grained sediments(175±82 ind./10 cm2).Nematodes were predominant in all studied sites.A total of 70 species be-longing to 52 genera and 18 families were identified in the study *** was a significant difference in nematode abundance(ANOVA,F=2.38,P63μm),with dominant species belonging to the genus Bathylaimus,Ptycho-laimellus,Spirinia,and *** trophic groups were dominated by non-selective deposit feeders(40.7%)and epistrate feed-ers(41.29%).In contrast,the species composition in medium grain sands was characterized by a low species diversity index and a high Simpson dominance *** communities showed similar dominant species compositions belonging to a single genus Bathylaimus,Enoplolaimus,and Oncholaimus,and in terms of trophic structure-representatives of deposit feeders(46.15%),preda-tors,and omnivores(64.71%)*** divergence of meiofaunal community structures can be explained by abiotic factors such as sediment grain size,salinity,and organic carbon ***,sediment particle size can explain the diversity of nematodes at the level of in abundance,diversity indices,and trophic *** highest nematode density and diversity coincided with

关键词： meiofauna nematodes sandy intertidal zone sediment grain size Yellow Sea

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