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Multispectral light scattering endoscopic imaging of esophageal precancer

Light(Science & Applications) 2017年第1期6卷 45-54页

作者： Le Qiu Ram Chuttani Douglas K Pleskow Vladimir Turzhitsky Umar Khan yuri n zakharov Lei Zhang Tyler M Berzin Eric U Yee Mandeep S Sawhney Yunping Li Edward Vitkin Jeffrey D Goldsmith Irving Itzkan Lev T Perelman Center for Advanced Biomedical Imaging and Photonics Division of GastroenterologyDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard UniversityBostonMA 02215USA Division of Gastroenterology Department of MedicineBeth Israel Deaconess Medical CenterHarvard UniversityBostonMA 02215USA Department of Pathology Beth Israel Deaconess Medical CenterHarvard UniversityBostonMA 02215USA Department of Anesthesia Critical Care and Pain MedicineBeth Israel Deaconess Medical CenterHarvard UniversityBostonMA 02215USA Biological and Biomedical Sciences Program Harvard UniversityBostonMA 02215USA

Esophageal adenocarcinoma is the most rapidly growing cancer in *** the prognosis after diagnosis is unfavorable,the chance of a successful outcome increases tremendously if detected early while the lesion is still ***,the present standard-of-care,endoscopic surveillance,has major limitations,since dysplasia is invisible,often focal,and systematic biopsies typically sample less than one percent of the esophageal lining and therefore easily miss *** solve this problem we developed a multispectral light scattering endoscopic imaging *** surveys the entire esophageal lining and accurately detects subcellular dysplastic *** system combines light scattering spectroscopy,which detects and identifies invisible dysplastic sites by analyzing light scattered from epithelial cells,with rapid scanning of the entire esophageal lining using a collimated broadband light beam delivered by an endoscopically compatible fiber optic *** we report the results of the first comprehensive multispectral imaging study,conducted as part of routine endoscopic procedures performed on patients with suspected *** a double-blind study that characterized the system’s ability to serve as a screening tool,55 out of 57 patients were diagnosed *** addition,a smaller double-blind comparison of the multispectral data in 24 patients with subsequent pathology at locations where 411 biopsies were collected yielded an accuracy of 90%in detecting individual locations of dysplasia,demonstrating the capability of this method to serve as a guide for biopsy.

关键词： biophotonics endoscopic multispectral imaging light scattering spectroscopy noninvasive cancer detection

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Recovery of Brachiopod and Ammonoid Faunas Following the End-Permian Crisis:Additional Evidence from the Lower Triassic of the Russian Far East and Kazakhstan

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Journal of Earth Science 2014年第1期25卷 1-44页

作者： yuri D zakharov Alexander M Popov Far Eastern Geological Institute Far Eastern BranchRussian Academy of Sciences

After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in recovery, and their taxonomic diversity had not recovered to Late Permian levels even by the Olenekian. The differential patterns of recovery between these two clades may reflect fundamental differences in physiology and behavior. Brachiopods were benthic organisms that were dependent on specific trophic sources, and their general reduction in size during the Early Triassic may have been a response to a relative paucity of food resources. In contrast, ammonoids were sluggish- nektic organisms that utilized a wider range of trophic sources and that suffered no comparable size decrease during the Early Triassic. Brachiopods may have been at a disadvantage also due to vulner- abilities associated with their larval stage, during which they had to locate a suitable substrate for set- tlement. In contrast, ammonoids had no larval stage and juveniles may have been dispersed widely into favorable habitats. These factors may account for differences in the relative success of ammonoids and brachiopods at high-latitude regions following the End-Permian mass extinction： ammonoids success- fully reeolonized the Boreal region during the Early Triassic whereas brachiopods did not.

关键词： Lower Triassic South Primorye Kazakhstan brachiopod ammonoid biotic recovery.

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nitrogen and Carbon Isotope Data of Olenekian to Anisian Deposits from Kamenushka/South Primorye, Far-Eastern Russia and Their Palaeoenvironmental Significance

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Journal of Earth Science 2018年第4期29卷 837-853页

作者： yuri D zakharov Micha Horacek Alexander M Popov Liana G Bondarenko Far Eastern Geological Institute of Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia BLT Wieselburg Research Center HBLFA Francisco-Josephinum Wieselburg 3250 Austria Institute of Lithospheric Research Vienna University Vienna 1090 Austria

The Kamenushka Formation, exposed in the northern part of South Primorye （Kamennshka-1 and Kamenushka-2 sections）, is one of the few localities in the world with richly fossiliferous Lower-Upper Olenekian sedimentary successions. Lower to Middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete ^15non- and ^13Corg- records for the Lower Triassic of this region. nine n- isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the Mesohedenstroemia bosphorensis Zone （upper part）, Shimanskyites shimanskyi and neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the Middle Spathian part of the nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and Majiashan sections.

关键词： Triassic n- and C-isotopes palaeoclimatology bio- and chemostratigraphy Pri- morye Russia.

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Unique Marine Olenekian-Anisian Boundary Section from South Primorye, Russian Far East

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Journal of China University of Geosciences 2005年第3期16卷 219-230页

作者： yuri D zakharov Alexander M Popov Galina I Buryi Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 RussiaFar Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia

To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova）（dominant）, Megaphyllites atlasoviensis zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus zakharov. Conodonts neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.

关键词： South Primorye Triassic Olenekian-Anisian boundary ammonoid conodont

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Significance of Caucasian Sections for Working out Carbon-Isotope Standard for Upper Permian and Lower Triassic (Induan) and Their Correlation with the Permian of north-Eastern Russia

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Journal of China University of Geosciences 2005年第2期16卷 141-151页

作者： yuri D zakharov Alexander S Biakov Aymon Baud Heinz Kozur Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Vladivostok 690022 Russia North-East Interdisciplinary Scientific Research InstituteRussian Academy of Sciences (Far Eastern Branch)Magadan 685000 RussiaMusee de GeologieBFSH2-UNI 1015 Lausanne Switzerland Rézsü u. 83H-1029 Budapest Hungary

Data obtained on conodont distribution in the Permian-Triassic Sovetashen Section of Transcaucasia provide further limitations on the age of the carbon-isotopic anomalies discovered by Baud et al. (1989). The significance of Caucasian sections for working out the carbon-isotope standard for the Upper Permian and Lower Triassic (Induan) is shown. Original data on carbon-isotope composition of bivalve and brachiopod shells from Permian sediments of north-Eastern Russia (Omolon and Okhotsk areas) have been obtained, which may be used for their correlation.

关键词： Armenia north-Eastern Russia Permian Triassic conodonts ammonoids bivalves brachiopods isotopic composition paleotemperatures correlation

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new Findings of Latest Early Olenekian(Early Triassic)Fossils in South Primorye,Russian Far East,and Their Stratigraphical Significance

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Journal of Earth Science 2021年第3期32卷 554-572页

作者： yuri D.zakharov Liana G.Bondarenko Alexander M.Popov Olga P.Smyshlyaeva Far Eastern Geological Institute Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia

Information on latest early Olenekian(latest Smithian)ammonoids is available apparently from only seven regions of the world,including South *** Smithian evidences on this topic are recorded from the West SMID(abbreviation from the Russian name of the quarry:"Building Materials and Details"),East SMID and Golyj Cape areas in South *** provides additional information on systematic composition of latest Smithian ammonoid,as well as conodont and brachiopod assemblages from the recently identified Shimanskyites shimanskyi Zone,located between lower Olenekian Anasibirites nevolini Zone and upper Olenekian Tirolites subcassianus *** are many common ammonoid species in the Shimanskyites shimanskyi Zone and the underlying Anasibirites nevolini Zone,e.g.,Prosphingitoides sp.,Arctoceras septentrionale(Diener),Churkites syskoi zakharov et Shigeta,Submeekoceras?subhhydaspis(Kiparisova),Prionites markevichi zakharov et Smyshlyaeva,?Anasibirites?simanenkoi zakharov et Smyshlyaeva,Xenoceltites?subvariocostatus zakharov et Smyshlyaeva,and Mianwaliites zimini zakharov et *** base of the Shimanskyites shimanskyi Zone,marked by a negativeδ13Corg excursion in the Kamenushka-2 Section by our previous study,coincides with the FO(first occurrence)of ammonoids Shimanskyites shimanskyi zakharov et Smyshlyaeva and Glyptophiceras ***(Waagen)and conodont Hindeodella budurovi *** zone is characterized additionally by some fossils common for the overlying upper Olenekian Tirolites subcassianus Zone:ammonoids of the genus Kamenushkaites,brachiopods Bittnerihyris margaritovi(Bittner)and Lepismatina *** conodont?neogondolella?(=?Borinella)jubata *** latest Smithian ammonoids recorded from the Shimanskyites shimanskyi Zone totally consist of 30 taxa belonging to 11 families(Sageceratidae,Ussuiriidae,Aspenitidae,Paranannitidae,Arctoceratidae,Proptychitidae,?Galfetitidae,Prionitidae,?Kashmiritidae,Xenoceltitidae and Palaeophyllitidae).Th

关键词： ammonoids conodonts brachiopods biostratigraphy Smithian Russia

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Atomic-scale mechanisms of void strengthening in tungsten

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Tungsten 2021年第1期3卷 65-71页

作者： yuri n.Osetsky Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

neutron and heavy-ion irradiation of tungsten produces nanometer-size vacancy voids,gas-filled bubbles and dislocation *** defect features can a ect mechanical properties and the impact can be quite significant because of their high *** the basic mechanisms of mechanical properties degradation is necessary for predicting radiation e *** can be made using discrete dislocation dynamics or/and finite element approaches which,however,need local interaction mechanisms as *** knowledge can be provided only by atomic-scale *** paper reports the results of an extensive atomic-scale modeling study of the interactions between moving edge dislocations and voids in *** main focus is on the e ects of the void size and ambient *** resolved shear stress was calculated for voids up to 9 nm in *** results are compared with the theoretical approach and with those obtained earlier for voids in body centered cubic(bcc)*** important role of the void surface has been revealed.

关键词： Tungsten neutron irradiation Voids Radiation-induced hardening Dislocations Dispersed barrier hardening

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A candidate of the Induan-Olenekian boundary stratotype in the Tethyan region

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Science China Earth Sciences 2003年第11期46卷 1182-1200页

作者：童金南 yuri D.zakharov Michael J.Orchard 殷鸿福 Hans J.Hansen Faculty of Earth Science China University of Geosciences Wuhan 430074 China Far Eastern Geological Institute Russian Academy of Sciences Vladivostok 690022Russia Geological Survey of Canada 101-605 Robson Street Vancouver B. C. V6B 5J3 Canada Geological Institute Copenhagen University Oster Voldgade 10 DK-1350 CopenhagenDenmark

The Olenekian Stage of the Lower Triassic is named from the Boreal Realm, but the stage has never been properly defined, nor has it been applied in the low-latitude Tethyan Realm, with exception of north Caucasus and Mangyshlak. This paper proposes a stratotype for the In-duan-Olenekian boundary in the low-latitude Tethyan Realm. South China is one of the main regions in the Tethyan Realm with well-developed Lower Triassic sequences and abundant fossils. According to the basic stratigraphic records and various accumulated data, we believe that the West Pingdingshan Section in Chaohu, Anhui Province is one of the best sequences to define the Induan-Olenekian boundary. The first appearance datum (FAD) of conodont neospathodus waageni is the preferred index to define the boundary. This datum lies 26 cm below the FAD of the ammonoids Flemingites and Euflemingites, and is located slightly prior to the top of the second Triassic normal magnetozone, and the peak of the first Triassic positive excursion of carbon isotope σ13C.

关键词： proposal, GSSP, Induan-Olenekian boundary, Lower Triassic, Chaohu of China.

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Atomistic material behavior at extreme pressures

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npj Computational Materials 2016年第1期2卷 93-96页

作者： Laurent Karim Béland yuri n Osetsky Roger E Stoller Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTNUSA

Computer simulations are routinely performed to model the response of materials to extreme environments,such as neutron(or ion)*** latter involves high-energy collisions from which a recoiling atom creates a so-called atomic displacement *** cascades involve coordinated motion of atoms in the form of supersonic *** shockwaves are characterized by local atomic pressures 415 GPa and interatomic distances o2Å.Similar pressures and interatomic distances are observed in other extreme environment,including short-pulse laser ablation,high-impact ballistic collisions and diamond anvil *** cascade simulations using four different force fields,with initial kinetic energies ranging from 1 to 40 keV,show that there is a direct relationship between these high-pressure states and stable defect *** important shortcoming in the modeling of interatomic interactions at these short distances,which in turn determines final defect production,is brought to light.

关键词： extreme defect latter

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A new cryptand/paraquat [2]pseudorotaxane

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Science China Chemistry 2010年第4期53卷 858-862页

作者： zakharov Lev n. SLEBODnICK Carla RHEInGOLD Arnold L. GIBSOn Harry W. Department of Chemistry and Biochemistry University of California Department of Chemistry Virginia Polytechnic Institute and State University

A new cryptand/paraquat [2]pseudorotaxane and its crown ether analog were synthesized and characterized by proton nMR, mass spectrometry, and single crystal X-ray analysis. The Job plots based on proton nMR data demonstrated that both the complex between cryptand 1 and paraquat derivative 2a and the complex between bis(p-phenylene)-34-crown-10 (3) and paraquat derivative 2b have 1:1 stoichiometry in solution. The apparent association constants (Ka,exp) of 1·2a and 3·2b calculated for 1:1 complexes were 1.4 (±0.2) × 104 and 4.7 (± 0.5) × 102 M-1, respectively. X-ray analysis showed that 1·2a is stabilized by ten hydrogen bonds and face-to-face π-stacking interactions in the solid state, while 3·2b is stabilized by four hydrogen bonds and face-to-face π-stacking interactions. As well as in the X-ray structure of 1·2c, a water molecule acts as a hydrogen bridge between the β-pyridinium protons of 2a and the ether oxygen atoms of 1 in 1·2a. The successful preparation of 1·2a demonstrated that the tert-butyl group is not big enough to be a stopper for rotaxanes based on 1.

关键词： host-guest system self-assembly pseudorotaxane cryptand paraquat

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