Input-output relations of the systems responsible for a reflex behavior     

Terzuolo CA  Poppele R 《Science (New York, N.Y.)》1967,158(3800):536-537

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G01Glupamid: a novel nutraceutical approach to canine and feline osteoarthritis     

A. MIOLO  P. BADINO  R. BARBERO  & G. RE 《Journal of veterinary pharmacology and therapeutics》2006,29(S1):202-203

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Thermal Structure of Jupiter's Upper Atmosphere Derived from the Galileo Probe     

A Seiff  DB Kirk  TCD Knight  LA Young  FS Milos  E Venkatapathy  JD Mihalov  RC Blanchard  RE Young  G Schubert 《Science (New York, N.Y.)》1997,276(5309):102-104

Temperatures in Jupiter's atmosphere derived from Galileo Probe deceleration data increase from 109 kelvin at the 175-millibar level to 900 ± 40 kelvin at 1 nanobar, consistent with Voyager remote sensing data. Wavelike oscillations are present at all levels. Vertical wavelengths are 10 to 25 kilometers in the deep isothermal layer, which extends from 12 to 0.003 millibars. Above the 0.003-millibar level, only 90- to 270- kilometer vertical wavelengths survive, suggesting dissipation of wave energy as the probable source of upper atmosphere heating.  相似文献   

Spatial Response of Mammals to Late Quaternary Environmental Fluctuations     

RW Graham  EL Lundelius  MA Graham  EK Schroeder  RS Toomey  E Anderson  AD Barnosky  JA Burns  CS Churcher  DK Grayson  RD Guthrie  CR Harington  GT Jefferson  LD Martin  HG McDonald  RE Morlan  HA Semken  SD Webb  L Werdelin  MC Wilson 《Science (New York, N.Y.)》1996,272(5268):1601-1606

Analyses of fossil mammal faunas from 2945 localities in the United States demonstrate that the geographic ranges of individual species shifted at different times, in different directions, and at different rates in response to late Quaternary environmental fluctuations. The geographic pattern of faunal provinces was similar for the late Pleistocene and late Holocene, but differing environmental gradients resulted in dissimilar species composition for these biogeographic regions. Modern community patterns emerged only in the last few thousand years, and many late Pleistocene communities do not have modern analogs. Faunal heterogeneity was greater in the late Pleistocene.  相似文献   

Locomotor primitives in newborn babies and their development   总被引：1，自引：0，他引：1  

Dominici N  Ivanenko YP  Cappellini G  d'Avella A  Mondì V  Cicchese M  Fabiano A  Silei T  Di Paolo A  Giannini C  Poppele RE  Lacquaniti F 《Science (New York, N.Y.)》2011,334(6058):997-999

How rudimentary movements evolve into sophisticated ones during development remains unclear. It is often assumed that the primitive patterns of neural control are suppressed during development, replaced by entirely new patterns. Here we identified the basic patterns of lumbosacral motoneuron activity from multimuscle recordings in stepping neonates, toddlers, preschoolers, and adults. Surprisingly, we found that the two basic patterns of stepping neonates are retained through development, augmented by two new patterns first revealed in toddlers. Markedly similar patterns were observed also in the rat, cat, macaque, and guineafowl, consistent with the hypothesis that, despite substantial phylogenetic distances and morphological differences, locomotion in several animal species is built starting from common primitives, perhaps related to a common ancestral neural network.  相似文献   

Diameter-Selective Raman Scattering from Vibrational Modes in Carbon Nanotubes   总被引：1，自引：0，他引：1  

AM Rao  E Richter  S Bandow  B Chase  PC Eklund  KA Williams  S Fang  KR Subbaswamy  M Menon  A Thess  RE Smalley  G Dresselhaus  MS Dresselhaus 《Science (New York, N.Y.)》1997,275(5297):187-191

Single wall carbon nanotubes (SWNTs) that are found as close-packed arrays in crystalline ropes have been studied by using Raman scattering techniques with laser excitation wavelengths in the range from 514.5 to 1320 nanometers. Numerous Raman peaks were observed and identified with vibrational modes of armchair symmetry (n, n) SWNTs. The Raman spectra are in good agreement with lattice dynamics calculations based on C-C force constants used to fit the two-dimensional, experimental phonon dispersion of a single graphene sheet. Calculated intensities from a nonresonant, bond polarizability model optimized for sp2 carbon are also in qualitative agreement with the Raman data, although a resonant Raman scattering process is also taking place. This resonance results from the one-dimensional quantum confinement of the electrons in the nanotube.  相似文献   

Single-Electron Transport in Ropes of Carbon Nanotubes     

M Bockrath  DH Cobden  PL McEuen  NG Chopra  A Zettl  A Thess  RE Smalley 《Science (New York, N.Y.)》1997,275(5308):1922-1925

The electrical properties of individual bundles, or "ropes," of single-walled carbon nanotubes have been measured. Below about 10 kelvin, the low-bias conductance was suppressed for voltages less than a few millivolts. In addition, dramatic peaks were observed in the conductance as a function of a gate voltage that modulated the number of electrons in the rope. These results are interpreted in terms of single-electron charging and resonant tunneling through the quantized energy levels of the nanotubes composing the rope.  相似文献