Cabbage cigarettes?     

Morton JF 《Science (New York, N.Y.)》1975,188(4189):683

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THE RELATION OF EVOLUTION TO MEDICINE     

Morton DJ 《Science (New York, N.Y.)》1926,64(1660):394-396

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Declining wild salmon populations in relation to parasites from farm salmon     

Krkosek M  Ford JS  Morton A  Lele S  Myers RA  Lewis MA 《Science (New York, N.Y.)》2007,318(5857):1772-1775

Rather than benefiting wild fish, industrial aquaculture may contribute to declines in ocean fisheries and ecosystems. Farm salmon are commonly infected with salmon lice (Lepeophtheirus salmonis), which are native ectoparasitic copepods. We show that recurrent louse infestations of wild juvenile pink salmon (Oncorhynchus gorbuscha), all associated with salmon farms, have depressed wild pink salmon populations and placed them on a trajectory toward rapid local extinction. The louse-induced mortality of pink salmon is commonly over 80% and exceeds previous fishing mortality. If outbreaks continue, then local extinction is certain, and a 99% collapse in pink salmon population abundance is expected in four salmon generations. These results suggest that salmon farms can cause parasite outbreaks that erode the capacity of a coastal ecosystem to support wild salmon populations.  相似文献   

Radical reactions of c60     

Krusic PJ  Wasserman E  Keizer PN  Morton JR  Preston KF 《Science (New York, N.Y.)》1991,254(5035):1183-1185

Photochemically generated benzyl radicals react with C(60) producing radical and nonradical adducts Rn C(60) (R = C(6)H(5)CH(2)) with n = 1 to at least 15. The radical adducts with n = 3 and 5 are stable above 50 degrees C and have been identified by electron spin resonance (ESR) spectroscopy as the allylic R(3)C(60)(.) (3) and cyclopentadienyl R(5)C(60)(.) (5) radicals. The unpaired electrons are highly localized on the C(60) surface. The extraordinary stability of these radicals can be attributed to the steric protection of the surface radical sites by the surrounding benzyl substituents. Photochemically generated methyl radicals also add readily to C(60). Mass spectrometric analyses show the formation of (CH(3))nC(60) with n = 1 to at least 34.  相似文献   

The percolation phase transition in sea Ice   总被引：1，自引：0，他引：1  

KM Golden  SF Ackley  VI Lytle 《Science (New York, N.Y.)》1998,282(5397):2238-2241

Sea ice exhibits a marked transition in its fluid transport properties at a critical brine volume fraction pc of about 5 percent, or temperature Tc of about -5 degreesC for salinity of 5 parts per thousand. For temperatures warmer than Tc, brine carrying heat and nutrients can move through the ice, whereas for colder temperatures the ice is impermeable. This transition plays a key role in the geophysics, biology, and remote sensing of sea ice. Percolation theory can be used to understand this critical behavior of transport in sea ice. The similarity of sea ice microstructure to compressed powders is used to theoretically predict pc of about 5 percent.  相似文献   

Optimization of fishmeal,fish oil and wheat in diets for juvenile sablefish,Anoplopoma fimbria          下载免费PDF全文

Ian Paul Forster  Briony Campbell  Bruce Morton  Brad Hicks  Mahmoud Rowshandeli 《Aquaculture Research》2017,48(6):3032-3040

Sablefish Anoplopoma fimbria is a piscivorous fish that is highly desirable as food. To ascertain the relationship of dietary protein, lipid and carbohydrate, eleven diets containing fishmeal, fish oil and wheat flour as test ingredients at different levels were formulated. The levels were chosen according to mixture experiment methodology, which varies the proportion of each test ingredient, while keeping their sum constant across all diets. The range of levels used in the test diets were as follows: fishmeal 430–600 g kg^?1, fish oil 100–270 g kg^?1 and wheat flour 30–200 g kg^?1. The sum of the test ingredients accounted for 900 g kg^?1 of all diets, with the remaining 100 g kg^?1 accounting for mineral and vitamin premix, binders, attractant, etc. Each diet, plus a commercial feed, was fed to three tanks of juvenile sablefish by hand twice daily for 11 weeks, using a completely random design. It was found that growth and feed efficiency were maximized by the highest dietary inclusion level of fish oil and fishmeal, corresponding to the lowest wheat flour level, that is 600 g kg^?1 fishmeal, 270 g kg^?1 fish oil and 30 g kg^?1 wheat flour.  相似文献