Voyager planetary radio astronomy at neptune     

Warwick JW  Evans DR  Peltzer GR  Peltzer RG  Romig JH  Sawyer CB  Riddle AC  Schweitzer AE  Desch MD  Kaiser ML  Farrell WM  Carr TD  de Pater I  Staelin DH  Gulkis S  Poynter RL  Boischot A  Genova F  Leblanc Y  Lecacheux A  Pedersen BM  Zarka P 《Science (New York, N.Y.)》1989,246(4936):1498-1501

Detection of very intense short radio bursts from Neptune was possible as early as 30 days before closest approach and at least 22 days after closest approach. The bursts lay at frequencies in the range 100 to 1300 kilohertz, were narrowband and strongly polarized, and presumably originated in southern polar regions ofthe planet. Episodes of smooth emissions in the frequency range from 20 to 865 kilohertz were detected during an interval of at least 10 days around closest approach. The bursts and the smooth emissions can be described in terms of rotation in a period of 16.11 +/- 0.05 hours. The bursts came at regular intervals throughout the encounter, including episodes both before and after closest approach. The smooth emissions showed a half-cycle phase shift between the five episodes before and after closest approach. This experiment detected the foreshock of Neptune's magnetosphere and the impacts of dust at the times of ring-plane crossings and also near the time of closest approach. Finally, there is no evidence for Neptunian electrostatic discharges.  相似文献   

Lunar apennine-hadley region: geological inplications of Earth-based radar and infrared measurements     

Zisk SH  Carr MH  Masursky H  Shorthill RW  Thompson TW 《Science (New York, N.Y.)》1971,173(3999):808-812

Recently completed high-resolution radar maps of the moon contain information on the decimeter-scale structure of the surface. When this information is combined with eclipse thermal-enhancement data and with high-resolution Lunar Orbiter photography, the surface morphology is revealed in some detail. A geological history for certain features and subareas can be developed, which provides one possible framework for the interpretation of the findings from the Apollo 15 landing. Frequency of decimeter-and meter-size blocks in and around lunar craters, given by the remote-sensed data, supports a multilayer structure in the Palus Putredinis mare region, as well as a great age for the bordering Apennine Mountains scarp.  相似文献   

Encounter with saturn: voyager 1 imaging science results     

Smith BA  Soderblom L  Beebe R  Boyce J  Briggs G  Bunker A  Collins SA  Hansen CJ  Johnson TV  Mitchell JL  Terrile RJ  Carr M  Cook AF  Cuzzi J  Pollack JB  Danielson GE  Ingersoll A  Davies ME  Hunt GE  Masursky H  Shoemaker E  Morrison D  Owen T  Sagan C  Veverka J  Strom R  Suomi VE 《Science (New York, N.Y.)》1981,212(4491):163-191

As Voyager 1 flew through the Saturn system it returned photographs revealing many new and surprising characteristics of this complicated community of bodies. Saturn's atmosphere has numerous, low-contrast, discrete cloud features and a pattern of circulation significantly different from that of Jupiter. Titan is shrouded in a haze layer that varies in thickness and appearance. Among the icy satellites there is considerable variety in density, albedo, and surface morphology and substantial evidence for endogenic surface modification. Trends in density and crater characteristics are quite unlike those of the Galilean satellites. Small inner satellites, three of which were discovered in Voyager images, interact gravitationally with one another and with the ring particles in ways not observed elsewhere in the solar system. Saturn's broad A, B, and C rings contain hundreds of "ringlets," and in the densest portion of the B ring there are numerous nonaxisymmetric features. The narrow F ring has three components which, in at least one instance, are kinked and crisscrossed. Two rings are observed beyond the F ring, and material is seen between the C ring and the planet.  相似文献   

HIV-1 nomenclature proposal     

Robertson DL  Anderson JP  Bradac JA  Carr JK  Foley B  Funkhouser RK  Gao F  Hahn BH  Kalish ML  Kuiken C  Learn GH  Leitner T  McCutchan F  Osmanov S  Peeters M  Pieniazek D  Salminen M  Sharp PM  Wolinsky S  Korber B 《Science (New York, N.Y.)》2000,288(5463):55-56

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Galileo multispectral imaging of the north polar and eastern limb regions of the moon   总被引：1，自引：0，他引：1  

Belton MJ  Greeley R  Greenberg R  Geissler P  McEwen A  Klaasen KP  Heffernan C  Breneman H  Johnson TV  Head JW  Pieters C  Neukum G  Chapman CR  Anger C  Carr MH  Davies ME  Fanale FP  Gierasch PJ  Thompson WR  Veverka J  Sagan C  Ingersoll AP  Pilcher CB 《Science (New York, N.Y.)》1994,264(5162):1112-1115

Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.  相似文献   

Aminopyralid Residue Impacts on Potatoes and Weeds     

Steven S. Seefeldt  Rick A. Boydston  Phil N. Kaspari  Mingchu Zhang  Erin Carr  Jeff Smeenk  David L. Barnes 《American Journal of Potato Research》2013,90(3):239-244

Aminopyralid is used in Alaska to control certain invasive weed species; however it appears to have an extended soil half-life in interior Alaska resulting in carry-over injury in potatoes. Field studies at three experiment stations in Delta Junction, Fairbanks, and Palmer, Alaska were established to determine the dose–response of weeds and above and below ground potato growth to soil-applied aminopyralid (0, 8, 15, 31, 62, and 123 g ae ha^?1) . Both prostrate knotweed and narrowleaf hawksbeard were susceptible to aminopyralid. At Delta Junction and Fairbanks, visual injury of potatoes greater than 25 % was observed at 15 g ae ha^?1 aminopyralid, whereas at Palmer visual injury was greater than 40 % at 8 g ae ha^?1, the lowest rate tested. Potato tuber production was reduced by aminopyralid at rates of 15 g ae ha^?1 and above at both Delta Junction and Palmer. Sub-samples of potato tubers from Delta Junction and Palmer were analyzed for aminopyralid content and grown out to determine if aminopyralid in tubers would reduce subsequent growth. The aminopyralid concentration in potato tubers increased with increasing field application rates, with 30 ppb extracted from tubers grown at the highest application rate (123 g ae ha^?1). All plants grown from daughter tubers except from control plots in Palmer exhibited injury symptoms. The number of emerged shoots, and shoot height decreased with increasing aminopyralid concentrations in the tuber, with injury rates greater than 70 % at 8 g ae ha^?1.  相似文献   

Descriptive overview of the 2011 epidemic of arboviral disease in horses in Australia     

SE Roche  R Wicks  MG Garner  IJ East  R Paskin  BJ Moloney  M Carr  P Kirkland 《Australian veterinary journal》2013,91(1-2):5-13

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Exercises in canine physical rehabilitation: range of motion of the forelimb during stair and ramp ascent     

J. G. Carr  D. L. Millis  H.‐Y. Weng 《The Journal of small animal practice》2013,54(8):409-413

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A record of the sub-Antarctic fur seal Arctocephalus tropicalis in Angola     

T. Carr  Nicole Carr  J.H.M. David 《African Zoology》2013,48(2)

Two individuals of the sub-Antarctic fur seal, Arctocephalus tropicalis, one of which was photographed, were seen on the beach 1 km south of the mouth of the Kwanza River, Angola, on 2 October 1983. This record represents a northerly extension by some 2 700 km of the previously recorded range. The nearest breeding colony is at Tristan da Cunha about 4 000 km south-west of this sighting.  相似文献   

Marine Seagrass Extract of Thalassia testudinum Suppresses Colorectal Tumor Growth,Motility and Angiogenesis by Autophagic Stress and Immunogenic Cell Death Pathways     

Ivones Hernndez-Balmaseda  Idania Rodeiro Guerra  Ken Declerck  Jos Alfredo Herrera Isidrn  Claudina Prez-Novo  Guy Van Camp  Olivier De Wever  Kethia Gonzlez  Mayrel Labrada  Adriana Carr  Geovanni Dantas-Cassali  Diego Carlos dos Reis  Livan Delgado-Roche  Roberto Rafael Nuez  Ren Delgado-Hernndez  Miguel David Fernndez  Miriam T. Paz-Lopes  Wim Vanden Berghe 《Marine drugs》2021,19(2)

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