Science and Human Nature     

Adrian ED 《Science (New York, N.Y.)》1954,120(3122):679-684

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Computer science. Program proves that checkers, perfectly played, is a no-win situation     

Cho A 《Science (New York, N.Y.)》2007,317(5836):308-309

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Cryptography. Quantum network set to send uncrackable secrets     

Cho A 《Science (New York, N.Y.)》2008,322(5898):32-33

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Inquiry learning. Integrating content detail and critical reasoning by peer review     

Iyengar R  Diverse-Pierluissi MA  Jenkins SL  Chan AM  Devi LA  Sobie EA  Ting AT  Weinstein DC 《Science (New York, N.Y.)》2008,319(5867):1189-1190

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The southern route "out of Africa": evidence for an early expansion of modern humans into Arabia     

Armitage SJ  Jasim SA  Marks AE  Parker AG  Usik VI  Uerpmann HP 《Science (New York, N.Y.)》2011,331(6016):453-456

The timing of the dispersal of anatomically modern humans (AMH) out of Africa is a fundamental question in human evolutionary studies. Existing data suggest a rapid coastal exodus via the Indian Ocean rim around 60,000 years ago. We present evidence from Jebel Faya, United Arab Emirates, demonstrating human presence in eastern Arabia during the last interglacial. The tool kit found at Jebel Faya has affinities to the late Middle Stone Age in northeast Africa, indicating that technological innovation was not necessary to facilitate migration into Arabia. Instead, we propose that low eustatic sea level and increased rainfall during the transition between marine isotope stages 6 and 5 allowed humans to populate Arabia. This evidence implies that AMH may have been present in South Asia before the Toba eruption.  相似文献   

Genome sequence of the PCE-dechlorinating bacterium Dehalococcoides ethenogenes     

Seshadri R  Adrian L  Fouts DE  Eisen JA  Phillippy AM  Methe BA  Ward NL  Nelson WC  Deboy RT  Khouri HM  Kolonay JF  Dodson RJ  Daugherty SC  Brinkac LM  Sullivan SA  Madupu R  Nelson KE  Kang KH  Impraim M  Tran K  Robinson JM  Forberger HA  Fraser CM  Zinder SH  Heidelberg JF 《Science (New York, N.Y.)》2005,307(5706):105-108

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The historic influence of dams on diadromous fish habitat with a focus on river herring and hydrologic longitudinal connectivity     

Carolyn J. Hall  Adrian Jordaan  Michael G. Frisk 《Landscape Ecology》2011,26(1):95-107

The erection of dams alters habitat and longitudinal stream connectivity for migratory diadromous and potamodromous fish species and interrupts much of organismal exchange between freshwater and marine ecosystems. In the US, this disruption began with colonial settlement in the seventeenth century but little quantitative assessment of historical impact on accessible habitat and population size has been conducted. We used published surveys, GIS layers and historical documents to create a database of 1356 dams, which was then analyzed to determine the historical timeline of construction, use and resultant fragmentation of watersheds in Maine, US. Historical information on the anadromous river herring was used to determine natural upstream boundaries to migration and establish total potential alewife spawning habitat in nine watersheds with historic populations. Dams in Maine were constructed beginning in 1634 and by 1850 had reduced accessible lake area to less than 5% of the virgin 892 km² habitat and 20% of virgin stream habitat. There is a near total loss of accessible habitat by 1860 that followed a west-east pattern of European migration and settlement. Understanding historic trends allows current restoration targets to be assessed and prioritized within an ecosystem-based perspective and may inform expectations for future management of oceanic and freshwater living resources.  相似文献   

The practical use of semiparametric models in field trials     

Maria Durban  Christine A. Hackett  James W. McNicol  Adrian C. Newton  William T. B. Thomas  Iain D. Currie 《Journal of Agricultural, Biological & Environmental Statistics》2003,8(1):48-66

This article examines the practical use of semiparametric models in the analysis of field trials—that is, models with parameterized treatment effects and additive terms derived by a data-driven approach using a locally weighted running line smoother (loess). We discuss graphical methods to identify spatial structure in the data and model selection procedures to choose the degree of smoothing. Once the spatial part of the model has been chosen, hypotheses about the treatment effects may be tested. Semiparametric models are used to analyze two barley field trials exhibiting spatial trends. The first has a single experimental treatment and a row-column design. The second has a split-plot design, and we use a semiparametric model which accounts for the randomization at the different strata of this design. We compare the semiparametric analyses with classical analyses of variance and with alternative spatial models. We find that semiparametric models give a good insight into spatial variation in the field and can improve the precision of parameter estimates.  相似文献   

The enantiomeric composition of triadimenol produced during metabolism of triadimefon by fungi. Part II: Differences between fungal species     

Adrian H. B. Deas  Terence Clark  Geoffrey A. Carter 《Pest management science》1984,15(1):71-77

The fungi Coriolus versicolor, Cladosporium cucumerinum, Botrytis cinerea and Fusarium culmorum, in shake culture, metabolised triadimefon to triadimenol. Analyses by gas–-liquid chromatography of the triadimenol showed that the fungi produced different qualitative and quantitative combinations of the four possible enantiomers, and that these differences were reproducible. The relationship between the enantiomeric composition of the triadimenol produced and the sensitivity of the test fungi to triadimefon, is discussed in the light of published data on the differences in antifungal activity shown by these enantiomers.  相似文献   

Response of susceptible and resistant peach-potato aphids Myzus persicae (Sulz.) to insecticides in leaf-dip bioassays     

Roman M. Sawicki  Adrian D. Rice 《Pest management science》1978,9(6):513-516

The response of susceptible (S), moderately resistant (R₁) and strongly resistant (R₂) peach-potato aphids, Myzus persicae (Sulz.) to organophosphorus, carbamate and pyrethroid insecticides was tested by a leaf-dip bioassay. The aphids were placed on potato leaves (dipped in insecticide solutions 1–2 or 24 h before infestation) and their mortality examined 48 h later. R₁ aphids were virtually susceptible to most of the carbamates, demephion and acephate, but were slightly to moderately resistant (2.1–9.4 times) to permethrin, cypermethrin and (S)-α-cyano-3-phenoxybenzyl (1R)-cis-3-(2,2-dibromovinyl)-2,2-dimethylcyclopropanecarboxylate (I), (NRDC 161), to 5,6,7,8-tetrahydro-2-methylquinolin-4-yl dimethylcarbamate (II), (Hoechst 25 682) and demeton-S-methyl. R₂ aphids resisted more strongly or very strongly (between 65 and 1280 times) the pyrethroids, demeton-S-methyl (×94), II (×83) and demephion (×9), and were slightly to moderately (2–5 times) resistant to acephate, pirimicarb, ethiofencarb and 2-(dimethylcarbamoyloxyimino)-3-methoxyimino-N,N- dimethylbutyramide (III), (DPX 3853). Both resistant strains were susceptible to nitrilacarb [4,4-dimethyl-5-(methylcarbamoyloxyimino)pentanenitrile] complex (1:1) with zinc chloride (IV), (AC 85 258). The implications of these results in terms of practical aphid control are discussed.  相似文献