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1.
日本(虫寻)和底栖短桨蟹线粒体DNA 12SrRNA基因序列的初步研究 总被引：6，自引：1，他引：6
以相应引物对日本和底栖短桨蟹的线粒体 DNA1 2 S r RNA基因片段进行了 PCR扩增和序列测定 ,分析比较了 2种间序列差异。结果表明 :日本 1 2 S r RNA基因片段长度为 41 4 bp,底栖短桨蟹为 41 5bp,2种的 A,T,G,C含量分别为 1 51 bp(36.47% ) ,1 53bp(36.96% ) ,43bp(1 0 .39% ) ,67bp(1 6.1 8% )和 1 50 bp(36.1 4 % ) ,1 55bp(37.35% ) ,44bp(1 0 .60 % ) ,66bp(1 5.90 % )。 2种间共出现了 3个碱基的缺失 /插入和 38bp的序列差异 ,其碱基转换与碱基颠换比约为 2 .1 7。 相似文献
2.
Gymnodinium mikimotoi, a senior synonym ofGymnodinium nagasakiense often causes red tides in coastal waters of the western part of Japan. The photosynthetic pigment composition of two strains ofG. mikimotoi were analyzed by HPLC. They contain chlorophyllc
3 which has not been reported from dinoflagellates. They also contain fucoxanthin, 19'-hexanoyloxyfucoxanthin and 19'-butanoyloxyfucoxanthin as major carotenoides, which are anomalous in dinoflagellates. The pigment composition ofG. mikimotoi is compared with that ofGyrodinium aureolum which occur in European waters and is thought as a conspecific species withG. mikimotoi by several authors. 相似文献
3.
Tomoharu Miyamoto Reiko Hamamoto Takeru Yanagi 《Geochimica et cosmochimica acta》2010,74(5):1471-1484
We analyzed Rb-Sr-Nd isotope ratios of mineral dust in total aerosol load collected with rainwater continuously from 1998 to 2006 at the summit of Mt. Sefuri, northern Kyushu, southwestern Japan. During this period, the total mass of the dust generally increased in late winter, peaked in early spring, and then decreased.87Sr/86Sr in atmospheric mineral dust varied from 0.7096 to 0.7180, and εNd(0)CHUR from −19.9 to −3.5. During heavy deposition periods, the dust had high 87Sr/86Sr isotope ratios and low to middle εNd(0)CHUR values, respectively. These compositions are comparable to those of sand and loess in arid areas of Northeast China, Takla Makan and Western Beijing. Such particles were transported by westerlies from those areas to northern Kyushu in winter and spring. In summer and autumn, the isotopic compositions of the dust varied greatly; however, during light deposition periods, the Sr isotope composition was low. In these seasons, the contributions to the dust from Japanese soils and volcanic ash, transported by southern winds, were relatively larger than in winter and spring because of decreased mineral dust particle transport from the continent. Nevertheless, fine sandy desert particles and loess in general accounted for most mineral dust deposition in northern Kyushu year-round, even in summer. Local soils derived from weathered granite and volcanic ash were minor components only.The net mass of water-insoluble inorganic matter in the collected mineral dust fluctuated from year-to-year; deposition on Mt. Sefuri was relatively large before 2001, decreased from 2002 to 2005, and increased greatly in spring 2006. These year-to-year differences probably reflected changes in the strength of the westerlies and in climate conditions in the arid source areas. 相似文献
4.
Catherine Heymans Ludovic Van Waerbeke David Bacon Joel Berge Gary Bernstein Emmanuel Bertin Sarah Bridle Michael L. Brown Douglas Clowe Håkon Dahle Thomas Erben Meghan Gray Marco Hetterscheidt Henk Hoekstra Patrick Hudelot Mike Jarvis Konrad Kuijken Vera Margoniner Richard Massey Yannick Mellier Reiko Nakajima Alexandre Refregier Jason Rhodes Tim Schrabback David Wittman 《Monthly notices of the Royal Astronomical Society》2006,368(3):1323-1339
5.
T. Morita Y. Sakawa Y. Kuramitsu H. Tanji H. Aoki T. Ide S. Shibata N. Onishi C. Gregory A. Diziere J. Waugh N. Woolsey Y. Sano A. Shiroshita K. Shigemori N. Ozaki T. Kimura K. Miyanishi R. Kodama M. Koenig H. Takabe 《Astrophysics and Space Science》2011,336(1):283-286
Collisionless shocks in counter-streaming plasmas, created by the high-power laser system Gekko XII HIPER, are investigated. The shock structure and density are measured by optical diagnostics such as shadowgraphy, interferometry, and streaked interferometry. The plasma density and temperature are estimated from self-emission measurements with visible light by streaked optical pyrometer and gated optical imager. Brightness temperatures are calculated considering the efficiency of the detectors, and electron temperatures are estimated. 相似文献
6.
7.
Alvaro de la Cámara C. R. Mechoso K. Ide R. Walterscheid G. Schubert 《Climate Dynamics》2010,35(6):965-975
The present paper examines the vortex breakdown and large-scale stirring during the final warming of the Southern Hemisphere
stratosphere during the spring of 2005. A unique set of in situ observations collected by 27 superpressure balloons (SPBs)
is used. The balloons, which were launched from McMurdo, Antarctica, by the Stratéole/VORCORE project, drifted for several
weeks on two different isopycnic levels in the lower stratosphere. We describe balloon trajectories and compare them with
simulations obtained on the basis of the velocity field from the GEOS-5 and NCEP/NCAR reanalyses performed with and without
VORCORE data. To gain insight on the mechanisms responsible for the horizontal transport of air inside and outside the well-isolated
vortex we examine the balloon trajectories in the framework of the Lagrangian properties of the stratospheric flow. Coherent
structures of the flow are visualized by computing finite-time Lyapunov exponents (FTLE). A combination of isentropic analysis
and FTLE distributions reveals that air is stripped away from the vortex’s interior as stable manifolds eventually cross the
vortex’s edge. It is shown that two SPBs escaped from the vortex within high potential vorticity tongues that developed in
association with wave breaking at locations along the vortex’s edge where forward and backward FTLE maxima approximately intersect.
The trajectories of three SPBs flying as a group at the same isopycnic level are examined and their behavior is interpreted
in reference to the FTLE field. These results support the concept of stable and unstable manifolds governing transport of
air masses across the periphery of the stratospheric polar vortex. 相似文献
8.
A simple theoretical model of atmospheric radiative equilibrium is solved analytically to help understand the energetics
of maintaining Earth's tropical and subtropical climate. The model climate is constrained by energy balance between shortwave
(SW) and longwave (LW) radiative fluxes. Given a complete set of SW and LW optical properties in each atmospheric layer, the
model yields a unique equilibrium-temperature profile. In contrast, if the atmospheric temperature profile and SW properties
are prescribed, the model yields essentially two distinct LW transmissivity profiles. This bimodality is due to a nonlinear
competition between the ascending and descending energy fluxes, as well as to their local conversion to sensible heat in the
atmosphere. Idealized slab models that are often used to describe the greenhouse effect are shown to be a special case of
our model when this nonlinearity is suppressed. In this special case, only one solution for LW transmissivity is possible.
Our model's bimodality in LW transmissivity for given SW fluxes and temperature profile may help explain certain features
of Earth's climate: at low latitudes the temperature profiles are fairly homogeneous, while the humidity profiles exhibit
a bimodal distribution; one mode is associated with regions of moist-and-ascending, the other with dry-and-subsiding air.
The model's analytical results show good agreement with the European Centre for Medium-Range Weather Forecasts' reanalysis
data. Sensitivity analysis of the temperature profile with respect to LW transmissivity changes leads to an assessment of
the low-latitude climate's sensitivity to the “runaway greenhouse” effect.
Received: 7 December 1999 / Accepted: 19 February 2001 相似文献
9.
Jianliang Deng Hiroshi Kameya Yukika Miyashita Jiro Kuwano Reiko Kuwano Junichi Koseki 《Engineering Geology》2011,123(4):302
Among the extensive failed slopes in the 2004 Niigata-ken Chuetsu Earthquake, Japan, a dip slope at Yokowatashi, Ojiya, was investigated intensively. The sliding plane was along a weak thin tuff sandy layer which had been deeply weathered. Triaxial compression tests and plane strain compression tests were performed on undisturbed specimens obtained by block sampling and boring sampling to evaluate the strength that was mobilized on the sliding plane. Stability analysis based on the test results reveals that, at normal time, without earthquake and without an extremely high groundwater level, the slope is stable. Furthermore, the calculation of earthquake-induced displacement provides a reasonable simulation of the failure of this slope. 相似文献
10.
An analytic radiative-equilibrium model is formulated where both short- and longwave radiation are treated as two-stream
(down- and upward) fluxes. An equilibrium state is defined in the model by the vertical temperature profile. The sensitivity
of any such state to the model atmosphere’s optical properties is formulated analytically. As an example, this general formulation
is applied to a single-column 11-layer model, and the model’s optical parameters are obtained from a detailed radiative parametrization
of a general circulation model. The resulting simple column model is then used to study changes in the Earth-atmosphere system’s
radiative equilibrium and, in particular, to infer the role of greenhouse trace gases, water vapor and aerosols in modifying
the vertical temperature profile. Multiple equilibria appear when a positive surface-albedo feedback is introduced, and their
stability is studied. The vertical structure of the radiative fluxes (both short- and longwave) is substantially modified
as the temperature profile changes from one equilibrium to another. These equilibria and their stability are compared to those
that appear in energy-balance models, which heretofore have ignored the details of the vertical temperature and radiation
profiles.
Received: 22 December 1995/Accepted: 17 January 1997 相似文献