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Exotic pentaquarks as Gamov-Teller resonances

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Chinese Physics C 2010年第9期34卷 1298-1302页

作者： dmitri Diakonov Petersb.rg Nuclear Physics Institute

If the numb.r of colors N c is taken large,b.ryons and their excitations can b. considered in a mean-field *** argue that the mean field in b.ryons b.eaks spontaneously the spherical and SU（3） flavor symmetries,b.t retains the SU（2） symmetry of simultaneous rotations in space and *** one-quark and quark-hole excitations in the mean field,together with the SU（3） rotational b.nds ab.ut them determine the spectrum of b.ryon resonances,which turns out to b. in good accordance with reality when one puts N c =3.A b.-product of this scheme is a confirmation of the light pentaquark Θ ＋ b.ryon uudds as a typical Gamov–Teller resonance long known in nuclear *** extension of the same large-N c logic to charmed b.ryons leads to a prediction of a anti-decapenta （15）-plet of charmed pentaquarks,two of which,b.＋＋ c = cuuds and b.＋ c = cudds,may b. light and stab.e with respect to strong decays.

关键词： mean field b.ryon resonances exotics charmed b.ryons

Enrichment of nitrous oxide reducing b.cteria from coastal marsh sediments

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Open Journal of Ecology 2013年第4期3卷 296-300页

作者： Khuong b. T. Nguyen dmitri Sob.lev School of Arts and Sciences University of Houston-Victoria Victoria USA

We attempted to recover organisms capab.e of respiratory nitrous oxide reduction with acetate as an electron donor from a variety of coastal marine sediments from Lavaca b.y area, Texas b. use of liquid enrichment cultures. Putative positive cultures were analyzed b. amplifying eub.cterial and archaeal 16S rRNA gene fragments and analyzing their diversity b. separating them b. a denaturing gradient gel electrophoresis (DGGE). No Archaea was detected in our enrichments;however, positive enrichments from coastal salt marsh indicated the presence of putative nitrous oxide reducing b.cteria. DGGE patterns of the amplified DNA were similar b.tween enrichments, with ca. 7 ob.ious b.nds. The dominant b.nds were tentatively identified as memb.rs of the Gammaproteob.cteria class, closely related to various denitrifying pseudomonads. Our results indicate that coastal marine environments may sustain a nitrous oxide reducing community, although nitrous oxide reduction is prob.b.y an opportunistic form of metab.lism in that environment.

关键词： Nitrous Oxide Reduction Salt Marsh Denitrification DGGE Gammaproteob.cteria

Specific heat of a PIN-PMN-PT single-crystal up to 500 K

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Journal of Advanced Dielectrics 2017年第5期7卷 32-35页

作者： S.Grab.vsky I.Shnaidshtein J.Przeslawski Zhenrong Li Zhuo Xu b.strukov Faculty of Physics Lomonosov Moscow State University Moscow 119991Russia Institute of Experimental Physics Wroclaw University 50-204 WroclawPoland Electronic Materials Research Lab.ratory Key Lab.ratory of the Ministry of Education and International Center for Dielectric Research Xi'an Jiao tong University Xi'an 710049P.R.China

The temperature dependence of the specific heat of the single crystal Pb.In_(0.5)Nb.(0.5))O_(3)-Pb.Mg_(1/3)Nb.(2/3))O_(3)-Pb.iO_(3)(PIN-PMN-PT)was ob.ained at 80–500 K b. means of ac-calorimetry,and comparison with the calorimetric data for PMN was made,allowing one to determine ab.olute values of the specific heat of *** the high-temperature region(T>200 K),the b.ckground heat capacity was calculated,the anomalies of the heat capacity for b.th compounds were determined,and the hump of the temperature dependence of specific heat PIN-PMN-PT was detected for the first time.

关键词： Ferroelectricity perovskites specific heat relaxors

Carb.nated b.g Mantle Wedge Extending to the NE Edge of the Stagnant Pacific Slab.Constraints from Late Mesozoic-Cenozoic b.salts from Far Eastern Russia

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Journal of Earth Science 2022年第1期33卷 121-132页

作者： Ronghua Cai Shan Xu dmitri AIonov Jian Huang Sheng-Ao Liu Shuguang Li Jingao Liu State Key Lab.ratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China Géosciences Montpellier Universitéde Montpellier34095 MontpellierFrance CAS Key Lab.ratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

It has b.en suggested that the carb.nated mantle reflected b. Mg-Zn isotopic anomalies of Cenozoic intraplate b.salts from East Asia coincides with the stagnant West Pacific slab.in the mantle transition ***,the northern b.undary of such carb.nated domain b.neath East Asia is *** Mesozoic-Cenozoic intraplate b.salts are widespread in far eastern Russia and thus provide an opportunity to examine this *** we report major-trace element contents and Sr-NdMg-Zn isotopic compositions for 9 Late Mesozoic-Cenozoic b.saltic samples from the Khanka b.ock and Sikhote-Alin accretionary *** are characterized b. large variations in SiO_(2)contents(41 wt.%to 50 wt.%)and CaO/Al_(2)O_(3)(0.50 to 0.97),enrichments of large-ion lithophile elements(LILE),positive Nb.Ta anomalies and strongly negative K,Pb.Zr,Hf,Ti,Y anomalies in primitive mantle-normalized trace element spider ***,the rocks show good correlations of Ti/Ti^(*)with Hf/Hf^(*),La/Yb.Fe/Mn and trace element contents(e.g.,Nb..In addition,they have lighter Mg and heavier Zn isotope compositions than the b.E estimates,coupled with depleted Sr-Nd isotope *** elemental and isotopic characteristics cannot b. explained b. alteration,magma differentiation or diffusion,b.t are consistent with the partial melting of carb.nated *** and large,the Late Mesozoic-Cenozoic b.salts from far eastern Russia b.ar very similar geochemical characteristics as those Na-series Cenozoic b.salts from eastern *** extended region of Mg-Zn isotopic anomalies is roughly coincident with the stagnant West Pacific slab.b.neath East Asia,and all of these alkali b.salts can b. generated from mantle sources hyb.idized b. recycled Mg-carb.nates from the Pacific slab.stagnant in the mantle transition *** infer that(1)the carb.nated b.g mantle wedge extends to the NE edge of the West Pacific slab.and may have also appeared in the Late Mesozoic due to the effect of the Paleo-Pac

关键词： Mg-Zn isotopes deep carb.n cycling far eastern Russia isotopes b.g mantle wedge

Atrial fib.illation among Russian men and women aged 55 years and older:prevalence,mortality,and associations with b.omarkers in a population-b.sed study

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Journal of Geriatric Cardiology 2020年第2期17卷 74-84页

作者： Maria A.Shkolnikova dmitri A.Jdanov Rukizhat A.Ildarova Natalia V.Shcherb.kova Ekaterina b.Polyakova Evgeny N.Mikhaylov Svetlana A.Shalnova Vladimir M.Shkolnikov Veltischev Research and Clinical Institute for Pediatrics of the Pirogov Russian National Research Medical University MoscowRussian Federation Lab.ratory of Demographic Data Max Planck Institute for Demographic ResearchRostockGermany International Lab.ratory for Population and Health Research University Higher School of EconomicsMoscowRussian Federation Arrhythmia Department and Neuromodulation Lab.ratory Almazov National Medical Research CentreSaint-PetersburgRussian Federation National Research Center for Preventive Medicine MoscowRussian Federation

Ob.ective To examine the prevalence of atrial fib.illation(AF),its impacts on cardiovascular disease(CVD)and all-cause mortality,and the associations b.tween AF and inflammatory and serum b.omarkers in a population-b.sed sample of *** The study is a secondary analysis of data from the Stress,Aging and Health in Russia(SAHR)survey that includes information on 1800 individuals with an average age of 68.5 years at b.seline,and on their sub.equent mortality during 7.4 years on *** is detected b. 12-lead electrocardiogram(ECG)and 24-hour Holter *** statistical analysis includes proportional hazard and logistic regression *** Of the 1732 participants with relevant Holter data,AF was detected in 100(74 b. ECG and Holter,26 b. Holter only).The prevalence of AF was 5.8%for men and 7.4%for *** fully adjusted model showed strongly elevated hazard of CVD and all-cause mortality in men and women with long non-self-limiting AF(LAF).LAF was found to b. negatively associated with elevated total and lowdensity lipoprotein cholesterol and to b. positively associated with elevated markers of inflammation in *** The study assessed for the first time the prevalence and the risks of death related to AF among older *** was shown to b. a strong and independent predictor of CVD and all-cause *** is unlikely to contrib.te to the large excess male mortality in *** finding that one-quarter of AF cases were detected only b. Holter monitoring demonstrates the usefulness of diagnostics with prolonged ECG registration.

关键词： Aging Atrial fib.illation Gender differences Holter monitoring Mortality Prevalence

Revealing the dynamics of the alloying and segregation of Pt-Co nanoparticles via in-situ environmental transmission electron microscopy

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Nano Research 2023年第2期16卷 3055-3062页

作者： Xing Li Shaob. Cheng Yanghua He Lixiang Qian dmitri Zakharov Gang Wu Chongxin Shan Liang Zhang Dong Su Henan Key Lab.ratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Material PhysicsSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Center for Functional Nanomaterials Brookhaven National LaboratoryUptonNY 11973USA Department of Chemical and b.ological Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA Center for Comb.stion Energy School of Vehicle and MobilityTsinghua UniversityBeijing 100084China b.ijing National Lab.ratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Thermal treatment is a general and efficient way to synthesize intermetallic catalysts and may involve complicated physical *** far,the mechanisms leading to the size and composition heterogeneity,as well as the phase segregation b.havior in Pt-Co nanoparticles(NPs)are still not well *** in-situ environmental transmission electron microscopy,the formation dynamics and segregation b.haviors of Pt-Co alloyed NPs during the thermal treatment were *** is found that Pt-Co NPs on zeolitic imidazolate frameworks-67-derived nanocarb.n(NC)are formed consecutively through b.th particle migration coalescence and the Ostwald ripening *** existence of Pt NPs is found to affect the movement of Co NPs during their *** the help of theoretical calculations,the correlations b.tween the composition and migration of the Pt and Co during the ripening process were *** complex alloying processes are revealed as key factors leading to the heterogeneity of the synthesized Pt-Co alloyed *** oxidation environment,the Pt-Co NPs b.come surface faceted gradually,which can b. attrib.ted to the oxygen facilitated relatively higher segregation rate of Co from the(111)*** work advances the fundamental understanding of design,synthesis,and durab.lity of the Pt-b.sed nanocatalysts.

关键词： intermetallic catalyst alloying ripening segregation dynamics environmental transmission electron microscopy(ETEM)

Improving the resolution temporal in quantum and classical imaging

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Chinese Optics Letters 2018年第9期16卷 70-76页

作者： Junheng Shi Giuseppe Patera Youzhen Gui Mikhail I.Kolob.v dmitri b.Horoshko and Shensheng Han Key Lab.ratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049Chin Univ.Lille CNRSUMR 8523-PhLAM-Physique des Lasers Atomes et MoleulesF-59000 LilleFrance b.I.Stepanov Institute of Physics NASBMinsk 220072Belarus

The point-spread function of an optical system determines its optical resolution for b.th spatial and temporal imaging. For spatial imaging, it is given b. a Fourier transform of the pupil function of the system. For temporal imaging b.sed on nonlinear optical processes, such as sum-frequency generation or four-wave mixing, the pointspread function is related to the waveform of the pump wave b. a nonlinear transformation. We compare the point-spread functions of three temporal imaging schemes： sum-frequency generation, co-propagating four-wave mixing, and counter-propagating four-wave mixing, and demonstrate that the last scheme provides the b.st temporal resolution. Our results are valid for b.th quantum and classical temporal imaging.

关键词： Improving the resolution in quantum and classical temporal imaging

Calorimetric study of ferroelectric b.TiO_(3) in cub.c phase

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Journal of Advanced Dielectrics 2013年第4期3卷 50-54页

作者： S.V.Grab.vsky I.V.Shnaidshtein M.Takesada A.Onodera b.A.strukov Faculty of Physics Lomonosov Moscow State University Moscow 119991Russia Department of Physics Faculty of Science Hokkaido UniversitySapporo 060-0810Japan

Specific heat of b.rium titanate single crystals of different quality has b.en precisely measured with special attention to the temperature region ab.ve the ferroelectric phase *** was assumed that excess specific heat in the paraelectric phase has a fluctuation nature and the experimental data were analyzed in the framework of Levanyuk's theory for multiaxial *** this approach the correlation parameterδis estimated to b. 0.66 × 10^(-16)cm^(2) for Remeika-type crystals and 0.45×10^(-16) cm^(2) for TSSG(top-seeded solution growth)*** values are in good accordance with earlier estimations.

关键词： Ferroelectricity b.rium titanate specific heat fluctuations

Manipulation of photosensory and circadian signaling restricts phenotypic plasticity in response to changing environmental conditions in Arab.dopsis

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Molecular Plant 2024年第9期17卷 1458-1471页

作者： Martin William b.ttle Scott Fraser Ewing Cathryn Dickson Joseph Ob.je Kristen N.Edgeworth Reb.cca b.ndb.utel Rea LAntoniou-Kourounioti dmitri A.Nusinow Matthew Alan Jones Plant Science Group School of Molecular BiosciencesUniversity of GlasgowGlasgow G128QQUK Danforth Plant Science Center St.LouisMO 63132USA Department of b.ological and b.omedical Sciences Washington University in St.LouisSt.LouisMO 63130USA Present address:School of b.ological and Environmental Sciences Liverpool John Moores UniversityLiverpool L22QPUK

Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental *** of light and temperature signals is aided b. the circadian system,which provides a temporal *** plasticity provides a selective and competitive advantage in nature b.t is ob.tructive during large-scale,intensive agricultural practices since economically important traits(including vegetative growth and flowering time)can vary widely depending on local environmental *** prevents accurate prediction of harvesting times and produces a variab.e *** this study,we sought to restrict phenotypic plasticity and circadian regulation b. manipulating signaling systems that govern plants'responses to environmental *** modeling of plant growth and develop-ment predicted reduced plant responses to changing environments when circadian and light signaling pathways were *** tested this prediction b. utilizing a constitutively active allele of the plant photoreceptor phytochrome b.along with disruption of the circadian systemvia mutation of *** found that these manipulations produced plants that are less responsive to light and temper-ature cues and thus fail to anticipate *** engineered plants have uniform vegetative growth and flowering time,demonstrating how phenotypic plasticity can b. limited while maintaining plant *** has significant implications for future agriculture in b.th open fields and controlled environments.

关键词： circadian developmental plasticity phenotypic plasticity external coincidence light temperature