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1.
The described fusulinids of the Moscovian Stage are found in the Asad-Abad section of the Sanandaj-Sirjan tectonic zone of Iran. Five successive fusulinid assemblages are distinguished. Three lower of them belong to the Kashirian Substage, the other two to the Podolskian Substage. The section studied is correlated with most complete sections of the Moscovian Stage in the western Tethys. Two new species Fusulinella (Moellerites) pygmea and Putrella primaris are identified; in addition to nominative taxon, the latter includes new subspecies P. primaris compacta. 相似文献
2.
To use two small fish Rivulus marmoratus (Cyprinodontiformes, Rivulidae) and the Japanese medaka Oryzias latipes (Belloniformes) as testing models in molecular ecotoxicology, we have cloned the cytochrome P450 1A (CYP1A) gene after screening of both genomic DNA libraries, and sequenced 11,863 and 7,243 bp including all the exons and introns with promoter regions, respectively. The Rivulus and the medaka CYP1A gene consisted of seven exons (including non-coding exons) with high homology to mammals. In the promoter region, Rivulus CYP1A gene has seven xenobiotic response elements (XREs) and two metal response elements (MREs), while the Japanese medaka CYP1A gene has six XREs and four MREs. Interestingly, medaka CYP1A gene has a number of MREs at the promoter, which may affect its response on metal exposure. We describe here the gene structure of both fish CYP1A genes. 相似文献
3.
Earlier results concerning sympathetic flares - physically related flares occurring in different active regions practically in the same time - and time-correlated radio bursts are compared with magnetic situation in active regions with related flaring and with the history and dynamics of its development. We found observational evidence abou the reality of sympathetic flares, demonstrating also that active regions in which they appear are physically related through common dynamical elements in which the evolution of their magnetic fields goes parallel. Such a process may sometimes occupy a very large volume of the photosphere and we believe that it might be related to the large-scale convective motions. 相似文献
4.
Bojan Vršnak Mateja Dumbović Jaša Čalogović Giuliana Verbanac Ivana Poljanǐć–Beljan 《Solar physics》2017,292(9):140
We present an analysis of the geoeffectiveness of corotating interaction regions (CIRs), employing the data recorded from 25 January to 5 May 2005 and throughout 2008. These two intervals in the declining phase of Solar Cycle 23 are characterised by a particularly low number of interplanetary coronal mass ejections (ICMEs). We study in detail how four geomagnetic-activity parameters (the Dst, Ap, and AE indices, as well as the Dst time derivative, \(\mathrm{dDst}/\mathrm{d}t\)) are related to three CIR-related solar wind parameters (flow speed, \(V\), magnetic field, \(B\), and the convective electric field based on the southward Geocentric solar magnetospheric (GSM) magnetic field component, \(\mathit{VB}_{s}\)) on a three-hour time resolution. In addition, we quantify statistical relationships between the mentioned geomagnetic indices. It is found that Dst is correlated best to \(V\), with a correlation coefficient of \(\mathrm{cc}\approx0.6\), whereas there is no correlation between \(\mathrm{dDst}/\mathrm{d}t\) and \(V\). The Ap and AE indices attain peaks about half a day before the maximum of \(V\), with correlation coefficients ranging from \(\mathrm{cc}\approx0.6\) to \(\mathrm{cc}\approx0.7\), depending on the sample used. The best correlations of Ap and AE are found with \(\mathit{VB}_{s}\) with a delay of 3 h, being characterised by \(\mathrm{cc}\gtrsim 0.6\). The Dst derivative \(\mathrm{dDst}/\mathrm{d}t\) is also correlated with \(\mathit{VB}_{s}\), but the correlation is significantly weaker \(\mathrm{cc}\approx 0.4\)?–?0.5, with a delay of 0?–?3 h, depending on the employed sample. Such low values of correlation coefficients indicate that there are other significant effects that influence the relationship between the considered parameters. The correlation of all studied geomagnetic parameters with \(B\) are characterised by considerably lower correlation coefficients, ranging from \(\mathrm{cc}=0.3\) in the case of \(\mathrm{dDst}/\mathrm{d}t\) up to \(\mathrm{cc}=0.56\) in the case of Ap. It is also shown that peak values of geomagnetic indices depend on the duration of the CIR-related structures. The Dst is closely correlated with Ap and AE (\(\mathrm{cc}=0.7\)), Dst being delayed for about 3 h. On the other hand, \(\mathrm{dDst}/\mathrm{d}t\) peaks simultaneously with Ap and AE, with correlation coefficients of 0.48 and 0.56, respectively. The highest correlation (\(\mathrm{cc}=0.81\)) is found for the relationship between Ap and AE. 相似文献
5.
6.
由50余个测点的大地电磁测深资料,讨论了该区的地壳-上地幔电性横向变化特征。按照上地幔第一低阻层顶面埋深,将测区划分为四类地区:浅埋深(55-90公里)、中浅埋深(90-110公里)、中深埋深(110-160公里)和深埋深(160-250公里)。讨论了本区六次大震例的深部电性背景。指出了上地幔顶部的梯度带地区、地壳内电性横向变化剧烈的地区和地壳内存在局部特殊增厚的低阻层地区将可以作为潜在震源区的深部电性判据之一 相似文献
7.
Thomas Foken Jan Pretel Reviewer J. Bednář Reviewer Z. Jaňour 《Studia Geophysica et Geodaetica》1988,32(3):318-328
In the present paper the first results of the international KOPEX-86 experiment are presented. The experiment took place at the Kopisty Atmospheric Observatory of the Institute of Physics of the Atmosphere in Prague as part of a special project of the Commission of the Academy of Sciences in Planetary Geophysics (KAPG) in June and July 1986. Using 4 ultrasonic anemometers at 4 levels up to 80 m, Doppler-SODAR and wind-, temperature- and radiation balance gradients from 2 to 80 m, a complex investigation of the atmospheric boundary layer in an industrial area was made. The authors present the first results of
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相似文献
| the anthropogenic influence on the energy exchange in the atmospheric boundary layer. |
| the influence of a complex terrain on the turbulent characteristics and their vertical distribution. |
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8.
Vladimír Kropáček Věra Vaňková Reviewer J. Fiala 《Studia Geophysica et Geodaetica》1985,29(3):290-299
Summary The distribution of radioactive(Th, U, K) and selected trace(Rb, Sr, Ba, Y, Zr, V, Cr, Ni) elements in volcanic rocks from the Opole and Jawor regions of the Lower Silesia has been studied. The behaviour of these elements in the studied rocks indicates that the Lower Silesian volcanic rocks are characterized by less differentiated type than other volcanic rocks of the Bohemian Massif, the Opole rock types probably having a less differentiated character than the Jawor rock types.
¶rt;a an¶rt;u a¶rt;uamu(Th, U, K) u m ¶rt;u(Rb, Sr, Ba, Y, Zr, V, Cr, Ni) m auu n¶rt;a am n u u uuu. a n mam n¶rt;num, m aum u uuu n¶rt;mam ¶rt; aamuu n¶rt; u ¶rt;uuau, aum u ana¶rt; uu. au a n¶rt;num, m auu n¶rt; amu n ¶rt;uuau ma ua n¶rt; u amu .相似文献
9.
Zbynek Sokol 《Studia Geophysica et Geodaetica》1995,39(1):74-83
Summary A series of Helmholtz equations has to be solved in short-range weather forecast models which use a splitting scheme of integration. For these purposes the successive overrelaxation, the Gauss-Seidel relaxation, the conjugate gradient method, the steepest descent method, the full-multigrid method and the direct method based on the minimum degree algorithm were used and their efficiencies were compared. It was found that the full-multigrid method was the most efficient among the iterative methods in terms of computational time, and that the effect rapidly increased with the grid size. The direct method may be an appropriate approach if the solution is repeated for various right-hand sides, but it requires large auxiliary computer memory. The selection of the optimum method depends on the concrete problem being solved and on the computer memory available. 相似文献
10.
Vladimír Schenk Vít Kárník Zdeňka Schenková Reviewer A. Zátopek 《Studia Geophysica et Geodaetica》1982,26(2):132-144
Summary The distribution of earthquake foci in the crust and the upper mantle indicates the position of mobile zones. Comparing epicentral maps of Central and Eastern Europe, known tectonic lines, results of deep seismic sounding and gravimetric survey enables a scheme of potential seismogenic zones, which correspond to active fault zones separating plates and blocks in the area, to be compiled. The level of earthquake activity varies along the investigated boundaries and can be considered as a measure of the intensity of the present geodynamic processes.Paper presented at the joint symposium AlO of the XVIIth General Assembly of the European Seismological Commission and of the 7th Annual Meeting of the European Geophysical Society, Budapest (Hungary), Aug. 21. – 29., 1980. 相似文献