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A Possible Feedback Mechanism Involving the Arctic Freshwater,the Arctic Sea Ice,and the North Atlantic Drift

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Advances in Atmospheric Sciences 2004年第5期21卷 784-801页

作者： odd Helge OTTeR Helge DRANGe Nansen environmental and Remote Sensing Center Edv. Griegsvei 3A5059 Bergen Bjerknes Centre for Climate Research Allégt. 55 5007 BergenNansen Environmental and Remote Sensing Center Edv. Griegsvei 3A5059 Bergen Bjerknes Centre for Climate Research Allégt. 55 5007 BergenGeophysical Institute University of Bergen Allégt. 70 5007 Bergen Nansen-Zhu International Research Centre Beijing 100029

Model studies point to enhanced warming and to increased freshwater ?uxes to high northern latitudes in response to global warming. In order to address possible feedbacks in the ice-ocean system in response to such changes, the combined e?ect of increased freshwater input to the Arctic Ocean and Arctic warming—the latter manifested as a gradual melting of the Arctic sea ice—is examined using a 3-D isopycnic coordinate ocean general circulation model. A suite of three idealized experiments is carried out: one control integration, one integration with a doubling of the modern Arctic river runo?, and a third more extreme case, where the river runo? is ?ve times the modern value. In the two freshwater cases, the sea ice thickness is reduced by 1.5–2 m in the central Arctic Ocean over a 50-year period. The modelled ocean response is qualitatively the same for both perturbation experiments: freshwater propagates into the Atlantic Ocean and the Nordic Seas, leading to an initial weakening of the North Atlantic Drift. Furthermore, changes in the geostrophic currents in the central Arctic and melting of the Arctic sea ice lead to an intensi?ed Beaufort Gyre, which in turn increases the southward volume transport through the Canadian Archipelago. To compensate for this southward transport of mass, more warm and saline Atlantic water is carried northward with the North Atlantic Drift. It is found that the increased transport of salt into the northern North Atlantic and the Nordic Seas tends to counteract the impact of the increased freshwater originating from the Arctic, leading to a stabilization of the North Atlantic Drift.

关键词： Arctic Ocean freshwater seaice North Atlantic Drift

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： R.V.Jolos e.A.Kolganova D.R.Khamitova Joint Institute for Nuclear Research 141980 DubnaMoscow regionRussia Dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

Gastric accommodation assessed by ultrasonography

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World Journal of Gastroenterology 2006年第18期12卷 2825-2829页

作者： odd Helge Gilja Johan Lunding Trygve Hausken Hans Gregersen National Centre for Ultrasound in Gastroenterology Haukeland University HospitalInstitute of MedicineUniversity of BergenBergenNorway Center for Visceral Biomechanics and Pain Aalborg Hospitaland Center for Sensory-motor InteractionAalborg UniversityDenmark

Gastric accommodation is important for the understanding of the pathophysiology in functional dyspepsia and is also relevant for symptom generation in other disorders. The term gastric accommodation has at least three different meanings： The accommodation process, the accommodation reflex, and the accommodation response. The gastric accommodation process is a complex phenomenon that describes how the size of the gastric compartment changes in response to a meal. The electronic barostat is considered the gold standard in assessing gastric accommodation. Imaging methods, including MRI, SPeCT, and ultrasonography may also be used, particularly in patients who are stress-responsive, e.g. functional dyspepsia patients, as a non-invasive and less stress-inducing method is favourable. Ultrasonography satisfies these criteria as it does not by itself distort the physiological response in stress-responsive individuals.

关键词： Ultrasonography Gastric accommodation Stomach Barostat Gastric relaxation 3D ultrasound

NON-LIFTING HYDRODYNAMIC INTeRACTION FORCeS BeTWeeN TWO SHIPS UNDeRGOING ARBITRARY HORIZONTAL MOTIONS IN CALM WATeR

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NON-LIFTING HYDRODYNAMIC INTERACTION FORCES BETWEEN TWO SHIP...

纪念顾懋祥院士海洋工程学术研讨会

作者： odd M.Faltinsen Centre for Ships and Ocean Structures(CeSOS) Department of Marine TechnologyNorwegian University of Science and TechnologyNorway

The lightering operation between two ships involves a low speed maneuvering *** two ships are maneuvering in close proximity,they experience the hydrodynamic loads that must take into account the interaction *** coupled maneuvering equations of two interacting ships in waves in the body-fixed coordinate systems were developed in Xiang and Faltinsen(2011a,2011d),which accounts for the wave effects by mean drift loads in the regular *** this paper we focus on the calm water hydrodynamic loads which appear in the right hand side of the maneuvering equations for two ships under arbitrary motions.A numerical approach based on 3-D source distribution is ***,validation of the numerical approach and parametric study of two bodies’ hydrodynamic interaction loads are carried *** overtaking maneuver was simulated based on the hydrodynamic loads evaluated by the present formulation. The basic assumptions are: (l)Potential flow applies;(2)Ships are at small to mediate forward speeds:the Froude numbers Fn of the two ships are assumed sufficiently small, i.e.,lower than～0.2,thus the free surface is dealt as solid boundary;(3)Horizontal motions,i.e.,surge,sway and yaw of two bodies/ships are considered. The present paper,which serves as a chapter in the first author’s PhD thesis at Norwegian University of Science and Technology,gives a summary of the authors’ recent work on the stated *** of the results has been presented in the 11 International Conference on Practical Design of Ships and Other Floating Structures(PRADS’ 2010);see Xiang and Faltinsen(2010,2011c) which presents a new method for two interacting ships in arbitrary horizontal motions,providing possibility of simulating two ships maneuvering up to the ***,some results were presented in the 2 International Conference on Ship Maneuvering in Shallow and Confined Water,Ship-to-ship Interaction(STS-2011);see Xiang,Skejic,Faltinsen and Berg(2011b) which simulated

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清开灵注射液的抗血栓作用及其机制研究

中国中药杂志 2009年第12期34卷 1549-1552页

作者：曹春雨梁爱华赵雍刘婷李春英易艳王金华薛宝云陈明伟 odd G Nilsen 中国中医科学院中药研究所北京100700 澳门科技大学

目的:探讨清开灵注射液(QKL)的抗血栓作用及其机制。方法:将SD大鼠随机分为对照组、模型组、QKL 2.5,5.0,10.0 ***-1组。QKL各剂量组均ip给药,每天1次×4 d。除正常对照组外,其余各组均于末次给予QKL前16 hip角叉菜胶(Ca)5 mg/只(0.5 mL... 详细信息

目的:探讨清开灵注射液(QKL)的抗血栓作用及其机制。方法:将SD大鼠随机分为对照组、模型组、QKL 2.5,5.0,10.0 ***-1组。QKL各剂量组均ip给药,每天1次×4 d。除正常对照组外,其余各组均于末次给予QKL前16 hip角叉菜胶(Ca)5 mg/只(0.5 mL)。于末次给予QKL后30 min,除了正常对照组iv生理盐水1 ***-1外,其余各组均iv给予内毒素(LPS)50μ***-1(1 ***-1),以注射LPS时作为造模0 h。于造模后2 h取血测定血浆TNF-α,IL-6含量和白细胞黏附分子CD11b/CD18表达;4,24 h测定外周血白细胞和血小板数量和测量尾部血栓长度(cm);120 h测定血小板聚集率。结果:清开灵注射液可明显抑制血栓形成,缩短尾部血栓长度;明显抑制体内炎性因子TNF-α和IL-6产生,降低白细胞黏附分子CD11b/CD18的表达水平;减轻由于血栓形成而导致的血小板消耗;降低血小板聚集率。结论:清开灵注射液的抗血栓作用与其抑制白细胞的激活和黏附,降低炎症反应和炎性因子产生,抑制血小板聚集等有关,这些作用机制与其清热解毒功效一致。

关键词：清开灵注射液清热解毒血栓炎症

Regular Orbits of extra-special Groups

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Algebra Colloquium 2016年第4期23卷 681-688页

作者： Joshua e. Goodson Texas A&M University at Galveston Department of General Academics P.O. Box 1675 Galveston Texas 77553 USA

In this paper, for odd primes p we find a recursive formula for the number of regular orbits of an extra-special p-group of exponent p2 acting on a faithful irreducible module over a finite field. This complements an ... 详细信息

关键词： extra-special orbits counting p-groups

Reduced Shell Model Calculations of ^111Sb and ^112Sb

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Chinese Physics Letters 2007年第6期24卷 1521-1524页

作者： e. Dikmen T, Akyǖrek Department of Physics Sǖleyman Demirel University Isparta Turkey

The low-lying states of the mid-heavy odd-even ^111Sb and odd-odd ^112Sb isotopes are calculated for the first time within the shell model framework. The shell model calculations have been carried out within the reduced model space including the single particle orbits ld5/2,097/2, ld3/2, 2Sl/2. We obtain the energy spectra for the ^111Sb and ^112Sb isotopes in the reduced model space by using CD-Bonn two-body effective nucleon-nucleon interaction. The energy spectra are compared to the experimental results to give some discussion about the low-lying states of ^111Sb and ^112Sb.

关键词： Calculations Reduced Model

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： Francisco e Jorge José R da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

OSCILLATORY BeHAVIOR OF SOLUTIONS OF CeRTAIN THIRD ORDeR MIXeD NeUTRAL DIFFeReNCe eQUATIONS

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Acta Mathematica Scientia 2013年第1期33卷 218-226页

作者： e.THANDAPANI N.KAVITHA Ramanujan Institute for Advanced Study in Mathematics University of MadrasChennai 600 005India

The objective of this paper is to study the oscillatory and asymptotic properties of the mixed type third order neutral difference equation of the form△（an△^2（xn＋bnxn-τ1＋cnxn＋τ2））＋qnx^βn＋1-σ1＋pnx^^βn＋1＋σ2=0,where （an）, （bn}, （cn}, （qn} and （pn} are positive real sequences, β is a ratio of odd positive integers, τ1, τ2, and σ2 are positive integers. We establish some sufficient conditions which ensure that all solutions are either oscillatory or converges to zero. Some examples are presented to illustrate the main results.

关键词： oscillation third order mixed type neutral difference equation