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Formation of Extended Covalently Bonded ni Porphyrin networks on the Au（lll） Surface

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nano Research 2011年第4期4卷 376-384页

作者： Sergey A. Krasnikov Catherine M. Doyle natalia n. Sergeeva Alexei B. Preobrajenski nikolay A.Vinogradov Yulia n. Sergeeva Alexei A. Zakharov Mathias O. Senge Attilio A. Cafolla School of Physical Sciences Dublin City University Glasnevin Dublin 9 Ireland Centre tbr Research on Adaptive nanostructures and nanodevices （CRAnn） School of Physics Trinity College Dublin Dublin 2 Ireland SFI Tetrapyrrole Laboratory School of Chemistry Trinity College Dublin Dublin 2 Ireland MAX-Lab Lund University Box 118 22100 Lund Sweden

The growth and ordering of {5,10,15,20-tetrakis（4-bromophenyl）porphyrinato}nickel（II）（niTBrPP） molecules on the Au（111） surface have been investigated using scanning tunnelling microscopy, X-ray absorption, core-level photoemission, and microbeam low-energy electron diffraction. When deposited onto the substrate at room temperature, the niTBrPP forms a well-ordered close-packed molecular layer in which the molecules have a flat orientation with the porphyrin macrocycle plane lying parallel to the substrate. Annealing of the niTBrPP layer on the Au（111） surface at 525 K leads to dissociation of bromine from the porphyrin followed by the formation of covalent bonds between the phenyl substituents of the porphyrin. This results in the formation of continuous covalently bonded porphyrin networks, which are stable up to 800 K and can be recovered after exposure to ambient conditions. By controlling the experimental conditions, a robust, extended porphyrin network can be prepared on the Au（111） surface that has many potential applications such as protective coatings, in sensing or as a host structure for molecules and clusters.

关键词： Porphyrins covalently bonded networks scanning tunnelling microscopy X-ray photoemission spectroscopy near-edge X-ray absorption fine structure Au(111)

A new species of Micryletta(Amphibia:Anura:Microhylidae)from the Langbian Plateau in southern Vietnam

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Zoological Research 2021年第6期42卷 726-733页

作者： nikolay A.Poyarkov Tan Van nguyen Jian-Huan Yang Vladislav AGorin Faculty of Biology Department of Vertebrate ZoologyMoscow State UniversityMoscow119234Russia Laboratory of Tropical Ecology Joint Russian-Vietnamese Tropical Research and Technological CenterHanoiVietnam Department of Species Conservation Save Vietnam’s WildlifeNinh BinhVietnam Kadoorie Conservation China Kadoorie Farm and Botanic GardenTai PoHong Kong SARChina

We report a new species of the genus Micryletta from the montane evergreen forest in the Bidoup-nui Ba national Park,Lam Dong Province,Langbian Plateau,southern Vietnam,based on molecular and morphological *** new species is diagnosed by a combination of the following morphological characters:body size small(snout-vent length(SVL)22.4 mm,single female);iris uniform black;snout nearly truncate in dorsal view,slightly rounded in profile;tibiotarsal articulation of adpressed limb reaching level of eye;dorsal surface smooth;supratympanic fold present,prominent;outer metatarsal tubercle absent;tips of toes very weakly dilated into small discs;finger webbing absent,toe webbing rudimentary;dorsal surfaces of head and body orange-red with small irregularly shaped dark-brown patches;dorsal surface of limbs pale dark brown with small reddish speckles;body flanks dark brown anteriorly fading to grayish brown posteriorly with brown spots in groin area;lateral sides of head immaculate blackish brown without white patches;coloration of ventral surfaces immaculate dark gray.

关键词： Plateau orange brown

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超表面:塑造光子学的未来

Science Bulletin 2024年第11期69卷 1607-1611页

作者： nikolay L.Kazanskiy Svetlana n.Khonina Muhammad A.Butt Samara national Research University Samara 443086Russia

A metasurface, often abbreviated as MS, represents a thin, artificially crafted surface consisting of an assembly of subwavelength structures that interact with light in distinct manners. Typically,smaller than the wavelength of the light they engage with, these structures empower precise management of light properties such as polarization, phase, and amplitude.

关键词： precise abbreviated 光子学

Dose-efficient scanning Compton X-ray microscopy

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Light(Science & Applications) 2023年第6期12卷 1141-1152页

作者： Tang Li JLukas Dresselhaus nikolay Ivanov Mauro Prasciolu Holger Fleckenstein Oleksandr Yefanov Wenhui Zhang David Pennicard Ann-Christin Dippel Olof Gutowski Pablo Villanueva-Perez Henry n.Chapman Saša Bajt The Hamburg Centre for Ultrafast Imaging 22761 HamburgGermany Center for Free-Electron Laser Science CFEL Deutsches ElektronenSynchrotron DESY22607 HamburgGermany Deutsches Elektronen Synchrotron DESY 22607 HamburgGermany Synchrotron Radiation Research and nanoLund Lund University22100 LundSweden Department of Physics Universität Hamburg22761 HamburgGermany

The highest resolution of images of soft matter and biological materials is ultimately limited by modification of the structure,induced by the necessarily high energy of short-wavelength *** the inelastically scattered X-rays at a photon energy of 60 keV(0.02 nm wavelength)offers greater signal per energy transferred to the sample than coherent-scattering techniques such as phase-contrast microscopy and projection *** present images of dried,unstained,and unfixed biological objects obtained by scanning Compton X-ray microscopy,at a resolution of about 70 *** microscope was realised using novel wedged multilayer Laue lenses that were fabricated to sub-ångström precision,a new wavefront measurement scheme for hard X rays,and efficient pixel-array *** doses required to form these images were as little as 0.02%of the tolerable dose and 0.05%of that needed for phase-contrast imaging at similar resolution using 17 keV photon *** images obtained provide a quantitative map of the projected mass density in the sample,as confirmed by imaging a silicon *** on these results,we find that it should be possible to obtain radiation damage-free images of biological samples at a resolution below 10 nm.

关键词： wedge dried scattered

Diagnostic value ultrasound signs of stones less than or equal to 10 mm and clinicoradiological variants of ureteric colic

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Asian Journal of Urology 2023年第1期10卷 39-49页

作者： Denis V.Krakhotkin Volodymyr A.Chernylovskyi Kemal Sarica Arman Tsaturyan Evangelos Liatsikos Jurijus Makevicius nikolay Yu Iglovikov Dmitry n.Pikhovkin Central District Hospital Outpatient ClinicSadovaya Lane 23KamenolomniRostov RegionRussia Private Urological Practice DniproUkraine Department of Urology Biruni University HospitalInstanbulTurkey Department of Urology University Hospital of PatrasPatrasGreece Department of Urology Medical University of ViennaViennaAustria Institute for Urology and Reproductive Health Sechenov UniversityMoscowRussia Institute of Clinical Medicine Faculty of MedicineVilnius UniversityVilniusLithuania Department and Clinic of Urology S.M.Kirov Military Medical Academy of the Ministry of Defense of the Russian FederationSt.PetersburgRussia Central District Hospital Department of SurgeryLenina Avenue 28AksayRostov RegionRussia

Objective:To determine the diagnostic value of ultrasound signs of urinary stones less than or equal to 10 mm and to determine clinico-radiological variants of ureteric ***:A total of 455 ultrasound investigations were performed in patients referring to emergency department with urolithiasis and symptoms suspected of ureteric colic between January 2021 and May *** addition to microscopic evaluation of urine sediment to detect different crystals and non-contrast spiral computed tomography to detect stones,B-mode and color Doppler sonography was performed to assess the presence of acoustic shadow(AS)and twinkle artifacts(TA)as possible signs of stone(s)in ***:While the sensitivity and specificity of AS and TA were higher than 90%in patients with stones greater than 5 mm;positive prognostic values of these parameters were found to be extremely low for stones with sizes of 1-3 mm with specificity and sensitivity values not exceeding 53%.The sensitivity and specificity of AS and TA in the upper and lower ureters were higher for stones greater than or equal to 5 than for compared to those less than 5 *** the same time,the diagnostic values of TA and AS for middle ureter stones were very *** most prevalent clinico-radiological variants of ureteric colic were types I,III,and V being observed in 39%,28% and 21% cases,***:Our results demonstrate that TA and AS parameters seem to have a very low sensitivity and specificity in the diagnosis of urinary stones less than 5 *** diagnostic value of TA and AS increase significantly in stones greater than or equal to 5 ***,clinicians need to be very careful for overestimating the diagnostic values of TA and AS for stones less than 5 mm and non-contrast spiral computed tomography must be the method of choice for patients presenting to emergency department with ureteric colic.

关键词： Ureteric colic Urolithiasis Ultrasound Twinkle artifact non-contrast computed tomography

CIED implantation in elderly patients： a single-center experience

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Journal of Geriatric Cardiology 2018年第6期15卷 460-462页

作者： nikolay n. ILOV Anatoly A. nECHEPUREnKO Albert M. ABDULKADYROV Damir R. PASKEEV Timur F. ASFAnDIYAROV Dmitry G. TARASOV Federal Center for Cardiovascular Surgery Astrakhan Russia Astrakhan State Medical University Astrakhan Russia

Thanks to the development of new medical technologies and improvement in medical care the last decades are characterized by the growth of elderly＇s number. The median age of the world＇s population is increasing because of a decline in birth rates and a 20-year increase in the average life span during the second half of the 20th century.

关键词： Arrhythmias Cardiac implantable electronic device Elderly Implantation

Observation of nonlinear fractal higher order topological insulator

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Light(Science & Applications) 2024年第11期13卷 2699-2714页

作者： Hua Zhong Victor O.Kompanets Yiqi Zhang Yaroslav V.Kartashov Meng Cao Yongdong Li Sergei A.Zhuravitskii nikolay n.Skryabin Ivan V.Dyakonov Alexander A.Kalinkin Sergei P.Kulik Sergey V.Chekalin Victor n.Zadkov Key Laboratory for Physical Electronics and Devices Ministry of EducationSchool of Electronic Science and EngineeringXi’an Jiaotong University710049 Xi’anChina Institute of Spectroscopy Russian Academy of SciencesTroitskMoscow 108840Russia Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia

Higher-order topological insulators(HOTIs)are unique materials hosting topologically protected states,whose dimensionality is at least by 2 lower than that of the *** states in such insulators may be strongly confined in their corners which leads to considerable enhancement of nonlinear processes involving such ***,all nonlinear HOTIs demonstrated so far were built on periodic bulk lattice ***,we demonstrate the first nonlinear photonic HOTI with the fractal *** their fractional effective dimensionality,the HOTIs constructed here on two different types of the Sierpiński gasket waveguide arrays,may support topological corner states for unexpectedly wide range of coupling strengths,even in parameter regions where conventional HOTIs become *** demonstrate thresholdless spatial solitons bifurcating from corner states in nonlinear fractal HOTIs and show that their localization can be efficiently controlled by the input beam *** observe sharp differences in nonlinear light localization on outer and multiple inner corners and edges representative for these fractal *** findings not only represent a new paradigm for nonlinear topological insulators,but also open new avenues for potential applications of fractal materials to control the light flow.

关键词： materials. flow. topological

The magnetic response of graphene split-ring metamaterials

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Light(Science & Applications) 2013年第1期2卷 124-127页

作者： nikitas Papasimakis Sukosin Thongrattanasiri nikolay I Zheludev FJ Garcıa de Abajo Optoelectronics Research Centre and Centre for Photonic Metamaterials University of SouthamptonSouthamptonUK IQFR–CSIC Serrano 11928006 MadridSpain Centre for Disruptive Photonic Technologies Nanyang Technological UniversitySingapore ICFO–Institut de Ciencies Fotoniques Mediterranean Technology Park08860 Castelldefels(Barcelona)Spain

Graphene has emerged as a promising platform for THz plasmonics,allowing high confinement,long lifetimes and fast electrical ***,we predict a strong magnetic dipole response by graphene split nanorings at THz frequencies,allowing the attainment of metamaterials with a high degree of field confinement(approximately one hundredth of the excitation wavelength)that is not reachable with conventional noble *** magnetic response of highly doped graphene split-rings in the far-infrared is much stronger than that displayed by gold structures of similar *** further explored stacked graphene layers as a practical way of producing high-frequency magnetism in thin,electrically tunable *** results support the great potential of using graphene to achieve electrically tunable magnetic metamaterials.

关键词： artificial magnetism graphene graphene plasmons metamaterials plasmonics

Fluctuating fine-scale spatial genetic structure in the common shrews (Eulipotyphla, Mammalia)

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Integrative Zoology 2023年第3期18卷 469-492页

作者： nikolay A.SHCHIPAnOV Artem V.ARTAMOnOV Sergey V.TITOV Svetlana V.PAVLOVA A.n.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia Department of Zoology and Ecology Penza State UniversityPenzaRussia

The spatial genetic structure is a topical issue in the studies of various aspects of ecology and *** the multilocus autocorrelation method with hypervariable microsatellite genetic markers,we investigated aﬁne-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300–1000 m(the Moscow chromosomal race).Spatial genetic autocorrelation analysis based on 5 microsatellite loci(expected heterozygosity>0.79)with 90 alleles revealed a consistent pattern of signiﬁcant positive genetic *** testing the autocorrelation at multiple scales from 25 to 500 m,we found that positive spatial genetic structure is detectable in distance classes ofnetic structure positively correlated with a higher ratio of nonresident individuals to residents’activity(number of captures).In contrast to nonresident animals,the residents demonstrated prominent genetic *** difference(FST)between the populations was signiﬁcant(0.016–0.051)and comparable with that between populations of different races analyzed previously(0.016–0.038).FST was not associated with geographic *** demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic proﬁles fromаcommon pool where the alleles are *** scheme predictsﬂuctuating genetic structure and random similar differences among local populations.

关键词： demographic pattern geneﬂow microsatellite spatial autocorrelation