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排序方式: 共有372条查询结果,搜索用时 15 毫秒
121.
The teenage birth control dilemma and public opinion 总被引:1,自引:0,他引:1
J Blake 《Science (New York, N.Y.)》1973,180(87):708-712
122.
123.
Perineal urethrostomy in cats 总被引:2,自引:0,他引:2
J A Blake 《Journal of the American Veterinary Medical Association》1968,152(10):1499-1506
124.
Muhammad Altaf Arain William James Shuttleworth Blake Farnsworth John Adams Omer Lutfi Sen 《Agricultural and Forest Meteorology》2000,100(4)
Micrometeorological variables measured in the BIOSPHERE-2 Center (B2C) enclosed rain forest biome for 1 year were compared with similar measurements made in the Amazon rain forest. In the B2C rain forest, the overlying glass and supporting structure significantly reduces (by approximately a factor of two) the incoming solar radiation. Monthly mean values of above-canopy and within-canopy air temperature, vapor pressure, and vapor pressure deficit are reasonably similar to those of the Amazon rain forest, but there are marked differences in the above-canopy values of these variables in the Arizona summer. Monthly mean diurnal trends also show significant differences. Measurements of vertical air temperature gradient clearly showed two very distinct environments in the 27.4 m high rain forest dome during daylight hours. There is a comparatively cool and fairly well-mixed environment (which is reasonably similar to that found in a natural rain forest) below about 10 m and a hot, thermally stable environment above about 15 m. The nature of the atmospheric turbulence within the B2C rain forest also is significantly different from that normally found in natural rain forests. There is little turbulent mixing above the forest canopy in this enclosed environment. These findings are important for guiding the operation and use of this experimental rain forest facility in future research and for understanding how the rain forest biome functions in an enclosed environment. 相似文献
125.
D. Nash S. P. Lanning P. Fox J. M. Martin N. K. Blake E. Souza R. A. Graybosch M. J. Giroux L. E. Talbert 《Cereal Chemistry》2006,83(3):255-258
A negative relationship between dough strength and dough extensibility would pose a problem for breeding hard wheats, as both dough strength and dough extensibility are desirable. We derived 77 recombinant inbred lines (RIL) from a cross between hard red spring wheat cultivars McNeal and Thatcher. McNeal produces flour with stronger dough and lower extensibility than does Thatcher. RIL were evaluated for strength‐related properties using mixograph analysis and extensibility parameters using the Kieffer attachment to the TA.XT2 texture analyzer. Additionally, the RIL were test baked. Measurements using the mixograph and the Kieffer attachment were highly heritable. Maximum dough extensibility (Extmax) was negatively correlated with resistance to extension (Rmax) (r = ‐0.74) and with mixograph tolerance (r = ‐0.45). Loaf volume was correlated with both Rmax (r = 0.42) and area under the extensigraph curve (r = 0.44) based on partial correlation analysis adjusted for protein differences. Extmax was negatively correlated with loaf volume (r = ‐0.26). The McNeal allele for polymorphism at the Gli1‐B1 locus on chromosome 1BS caused high dough‐mixing tolerance and low dough extensibility. Our results suggest that traditional selection criteria in hard red spring wheat, including tolerance to dough mixing and high loaf volume, may result in reduced dough extensibility. 相似文献
126.
Hasty R Hawthorne-Allen AM Averett T Barkhuff D Beck DH Beise EJ Blake A Breuer H Carr R Covrig S Danagoulian A Dodson G Dow K Farkhondeh M Filippone BW Gao J Herda MC Ito TM Jones CE Korsch W Kramer K Kowalski S Lee P McKeown RD Mueller B Pitt M 《Science (New York, N.Y.)》2000,290(5499):2117-2119
The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange quarks in generating nuclear magnetism. The measurement reported here provides an unambiguous constraint on strange quark contributions to the proton's magnetic moment through the electron-proton weak interaction. We also report evidence for the existence of a parity-violating electromagnetic effect known as the anapole moment of the proton. The proton's anapole moment is not yet well understood theoretically, but it could have important implications for precision weak interaction studies in atomic systems such as cesium. 相似文献
127.
Ouyang Z Takáts Z Blake TA Gologan B Guymon AJ Wiseman JM Oliver JC Davisson VJ Cooks RG 《Science (New York, N.Y.)》2003,301(5638):1351-1354
Intact, multiply protonated proteins of particular mass and charge were selected from ionized protein mixtures and gently landed at different positions on a surface to form a microarray. An array of cytochrome c, lysozyme, insulin, and apomyoglobin was generated, and the deposited proteins showed electrospray ionization mass spectra that matched those of the authentic compounds. Deposited lysozyme and trypsin retained their biological activity. Multiply charged ions of protein kinase A catalytic subunit and hexokinase were also soft-landed into glycerol-based liquid surfaces. These soft-landed kinases phosphorylated LRRASLG oligopeptide and D-fructose, respectively. 相似文献
128.
L V Melendez R D Hunt M D Daniel B J Blake F G Garcia 《Science (New York, N.Y.)》1971,171(976):1161-1163
Our study demonstrates for the first time that Herpesvirus saimiri can induce acute lymphocytic leukemia in owl monkeys (Aotus trivirgatus) and that malignant lymphoma can be induced in this species of nonhuman primates by the inoculation of the virus by various routes (intravenous, sub-cutaneous, and intradermal). 相似文献
129.
The average worldwide tropospheric mixing ratio of methane has increased by 11% from 1.52 parts per million by volume (ppmv) in January 1978 to 1.684 ppmv in September 1987, for an increment of 0.016 +/- 0.001 ppmv per year. Within the limits of our measurements, the global tropospheric mixing ratio for methane over the past decade is consistent either with a linear growth rate of 0.016 +/- 0.001 ppmv per year or with a slight lessening of the rate of growth over the past 5 years. No indications were found of an effect of the El Ni?o-Southern Oscillation-El Chichon events of 1982-83 on total global methane, although severe reductions were reported in the Pacific Northwest during that time period. The growth in tropospheric methane may have increased the water concentration in the stratosphere by as much as 28% since the 1940s and 45% over the past two centuries and thus could have increased the mass of precipitable water available for formation of polar stratospheric clouds. 相似文献
130.
de Gouw JA Middlebrook AM Warneke C Ahmadov R Atlas EL Bahreini R Blake DR Brock CA Brioude J Fahey DW Fehsenfeld FC Holloway JS Le Henaff M Lueb RA McKeen SA Meagher JF Murphy DM Paris C Parrish DD Perring AE Pollack IB Ravishankara AR Robinson AL Ryerson TB Schwarz JP Spackman JR Srinivasan A Watts LA 《Science (New York, N.Y.)》2011,331(6022):1295-1299
A large fraction of atmospheric aerosols are derived from organic compounds with various volatilities. A National Oceanic and Atmospheric Administration (NOAA) WP-3D research aircraft made airborne measurements of the gaseous and aerosol composition of air over the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico that occurred from April to August 2010. A narrow plume of hydrocarbons was observed downwind of DWH that is attributed to the evaporation of fresh oil on the sea surface. A much wider plume with high concentrations of organic aerosol (>25 micrograms per cubic meter) was attributed to the formation of secondary organic aerosol (SOA) from unmeasured, less volatile hydrocarbons that were emitted from a wider area around DWH. These observations provide direct and compelling evidence for the importance of formation of SOA from less volatile hydrocarbons. 相似文献