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51.
Harold E. Brooks Aaron R. Anderson Kathrin Riemann Irina Ebbers Heather Flachs 《Atmospheric Research》2007,83(2-4):294-305
Annual cycles of convectively important atmospheric parameters have been computed for a variety of from the National Center for Atmospheric Research (NCAR)/National Centers for Environmental Prediction (NCEP) global reanalysis, using 7 years of reanalysis data. Regions in the central United States show stronger seasonality in combinations of thermodynamic parameters than found elsewhere in North America or Europe. As a result, there is a period of time in spring and early summer when climatological mean conditions are supportive of severe thunderstorms.The annual cycles help in understanding the large-scale processes that lead to the combination of atmospheric ingredients necessary for strong convection. This, in turn, lays groundwork for possible changes in distribution of the environments associated with possible global climate change. 相似文献
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Irina A. Bilenko 《Solar physics》2004,221(2):261-282
The longitudinal distribution of coronal holes has been analyzed for the time interval 1976–2002. Coronal holes don't seem
to be randomly distributed. The cluster structure has been revealed in the time—space organization of coronal hole distribution.
The complexity and lifetime of clusters depend on the solar cycle phase. The comparison of active region and coronal hole
cluster structures shows that some coronal hole clusters as well as active region ones occur almost simultaneously in both
hemispheres, some clusters in the north or in the south hemisphere only. Some coronal hole clusters coincide with the active
region clusters and some do not coincide. They reflect the large-scale solar magnetic field distribution. 相似文献
53.
In the footsteps of Alexander the Great: searching for the origins of ancient zooplankton on the wild steppe of Central Asia 下载免费PDF全文
Mark Williams David J. Siveter Vincent Perrier Elena Mikhailova Anna Tarasenko Firuza Salimova Irina A. Kim 《Geology Today》2015,31(2):68-73
Rising above the modern town of Nurata, in Navoiy Province, eastern Uzbekistan is the ancient fortress of Alexander the Great, built as part of Alexander's campaigns to subjugate the Persian‐speaking Sogdian peoples that lived in this province of the Persian Empire in the 4th Century bc . Alexander passed this way in 327 bc , marching his ancient army through this beautiful but desolate landscape, and conquering all before him. His fortress was built in a strategic place at the boundary between fertile agricultural lands and a dry and uncompromising vastness of steppe that lies to the east. From Nurata, about one hour drive by car along a road that cuts eastwards across the desert, is the sleepy town of Jo'sh. In the mountains beyond Jo'sh sits the hamlet of Kanda, a few mud‐brick houses nestling at the head of a small valley where a spring emerges miraculously from a bone‐dry landscape. Hereabouts are telltale signs of ancient marine deposits yielding graptolites from rocks of the Silurian system. And in these rocks are the fossils of tiny arthropods that mark a fundamental shift in the marine arthropod zooplankton 425 million years ago. It is these fossils that we have chased halfway across the world to the steppe of Central Asia. 相似文献
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Beleneva IA 《Marine pollution bulletin》2011,62(2):382-387
The distribution of Staphylococcus aureus and Listeria monocytogenes in the sea water and marine organisms of Peter the Great and Nha Trang bays, the phenotypic properties and antibiotic sensitivity of the isolates were studied. S. aureus was recorded from 9.3% samples in the Sea of Japan and from 20.4% samples in the South China Sea, L. monocytogenes respectively from 5.9 % and 5.8 % samples. S. aureus and L. monocytogenes found in the tropics differed in their phenotypic properties from those found in the temperate zone. Antibiotic resistance was detected in 81.8% and 71.8% of S. aureus strains and in 19% and 71.4% of L. monocytogenes strains respectively from Peter the Great Bay and from Vietnam. The results show that multiresistant strains of S. aureus and L. monocytogenes are widespread throughout Peter the Great and Nha Trang bays and present a hazard to the health of humans and marine animals. 相似文献
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Stéphane Reboulet Peter F. Rawson Josep A. Moreno-Bedmar Maria B. Aguirre-Urreta Ricardo Barragán Yuri Bogomolov Miguel Company Celestina González-Arreola Vyara Idakieva Stoyanova Alexander Lukeneder Bertrand Matrion Vasily Mitta Hasina Randrianaly Zdenek Vaši?ek Evgenij J. Baraboshkin Didier Bert Stéphane Bersac Tamara N. Bogdanova Luc G. Bulot Jean-Louis Latil Irina A. Mikhailova Pierre Ropolo Ottilia Szives 《Cretaceous Research》2011,32(6):786-793
The 4th Kilian Group meeting (Dijon, France, 30th August 2010) focused on the Aptian and Albian Stages. For the Aptian, a two-fold division of the stage was adopted for the Mediterranean area with a boundary between the Dufrenoyia furcata and Epicheloniceras martini Zones. The main changes to the zonal scheme concern the Lower Aptian with: the introduction of a Deshayesites luppovi Subzone in the upper part of the Deshayesites oglanlensis Zone; the replacement of Deshayesites weissi by Deshayesites forbesi as new index-species of the second interval zone; the introduction of a Roloboceras hambrovi Subzone in the upper part of the D. forbesi Zone; and the subdivision of the D. furcata Zone into the D. furcata and Dufrenoyia dufrenoyi Subzones. For the Albian, the upper part of the Douvilleiceras mammillatum Zone (Lower Albian) is now characterized by a Lyelliceras pseudolyelli Subzone. The main amendments concern the Upper Albian. The base of this substage is defined by the base of the Dipoloceras cristatum Zone. Above it, the Upper Albian zonal scheme comprises in stratigraphic order the Mortoniceras pricei, Mortoniceras inflatum, Mortoniceras fallax, Mortoniceras rostratum, Mortoniceras perinflatum and Arrhaphoceras briacensis Zones. 相似文献
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Belskaya Irina N. Barucci Antonella M. Shkuratov Yurij G. 《Earth, Moon, and Planets》2003,92(1-4):201-206
Information on the surface structure of the Kuiper Belt objectscan be obtained from studies of their opposition brightening.Although KBOs are observed at a very limited phase angle rangethey represent a unique opportunity to study the backscatteringphenomenon down almost to zero phase angle. Preliminaryestimations of the opposition effect amplitude and width based oncomposite phase curves of four KBOs and two Centaurs showed theexistence of a very narrow opposition surge of about 0.1–0.2 mag at phase angles less than 0.1–0.2 deg. It may indicate a highporosity of the KBOs regoliths. Further observations are needed toconfirm this phenomenon. 相似文献
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正1 Introduction In the south of Eastern Transbaikalia in the border area with China and Mongolia,there are at least 300 saline without outlet lakes.They are confined to the semi-arid zone Daurian steppes with pronounced continental salinization processes and are mostly located on the bottoms of the intermountain basins.Their origin is related to evaporative concentration of fresh waters lakes filling. 相似文献