STEPHENS'S CALIFORNIA MAMMALS     

Jordan DS 《Science (New York, N.Y.)》1906,24(614):439-440

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Biomarkers of caloric restriction may predict longevity in humans     

Roth GS  Lane MA  Ingram DK  Mattison JA  Elahi D  Tobin JD  Muller D  Metter EJ 《Science (New York, N.Y.)》2002,297(5582):811

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Sampling Strategies for Mapping Soil Phosphorus and Soil Potassium Distributions in Cool Temperate Grassland   总被引：1，自引：0，他引：1  

Shi  Z.  Wang  K.  Bailey  J. S.  Jordan  C.  Higgins  A. J. 《Precision Agriculture》2000,2(4):347-357

Unlike the situation for arable soils, virtually nothing is known about the spatial dependencies of soil properties in cool temperate grassland or about what the optimal sampling strategies ought to be for mapping soil nutrient distributions in such situations. The aim of this study was to investigate the spatial variability in plant-available (soil) phosphorus and potassium in a grass silage field in Northern Ireland and devise optimal sampling strategies for mapping their distributions. Soil samples were collected from the field at 25 m intervals in a regular rectangular grid to provide a database of soil properties. Different data combinations were subsequently abstracted from this database for comparison purposes, and ordinary kriging used to produce interpolated soil maps. Soil potassium displayed greater spatial variability than soil phosphorus. In keeping with this observation, the results of three separate statistical procedures demonstrated that the optimal sample size for estimating the true population means was about twice as large for soil potassium as for soil phosphorus. Optimal sampling strategies, however, related not just to sample size but to sample combination and field shape as well.  相似文献   

Book review     

Jeff Jordan 《Agriculture and Human Values》2006,23(4):529-530

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Radar soundings of the subsurface of Mars   总被引：2，自引：0，他引：2  

Picardi G  Plaut JJ  Biccari D  Bombaci O  Calabrese D  Cartacci M  Cicchetti A  Clifford SM  Edenhofer P  Farrell WM  Federico C  Frigeri A  Gurnett DA  Hagfors T  Heggy E  Herique A  Huff RL  Ivanov AB  Johnson WT  Jordan RL  Kirchner DL  Kofman W  Leuschen CJ  Nielsen E  Orosei R  Pettinelli E  Phillips RJ  Plettemeier D  Safaeinili A  Seu R  Stofan ER  Vannaroni G  Watters TR  Zampolini E 《Science (New York, N.Y.)》2005,310(5756):1925-1928

The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick.  相似文献   

JOHN THOMAS GULICK,MISSIONARY AND DARWINIAN     

Jordan DS 《Science (New York, N.Y.)》1923,58(1512):509

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THE PRODUCTION OF SPECIES     

Jordan DS 《Science (New York, N.Y.)》1922,56(1451):448-449

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CONCERNING "SPECIES-GRINDING"     

Jordan DS 《Science (New York, N.Y.)》1927,66(1696):14-15

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Book review     

Jeff Jordan 《Agriculture and Human Values》2007,24(2):259-260

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Benchmark study on glyphosate-resistant crop systems in the United States. Part 2: Perspectives     

Owen MD  Young BG  Shaw DR  Wilson RG  Jordan DL  Dixon PM  Weller SC 《Pest management science》2011,67(7):747-757

A six-state, 5 year field project was initiated in 2006 to study weed management methods that foster the sustainability of genetically engineered (GE) glyphosate-resistant (GR) crop systems. The benchmark study field-scale experiments were initiated following a survey, conducted in the winter of 2005-2006, of farmer opinions on weed management practices and their views on GR weeds and management tactics. The main survey findings supported the premise that growers were generally less aware of the significance of evolved herbicide resistance and did not have a high recognition of the strong selection pressure from herbicides on the evolution of herbicide-resistant (HR) weeds. The results of the benchmark study survey indicated that there are educational challenges to implement sustainable GR-based crop systems and helped guide the development of the field-scale benchmark study. Paramount is the need to develop consistent and clearly articulated science-based management recommendations that enable farmers to reduce the potential for HR weeds. This paper provides background perspectives about the use of GR crops, the impact of these crops and an overview of different opinions about the use of GR crops on agriculture and society, as well as defining how the benchmark study will address these issues.  相似文献