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221.
JIYOUNG PARK PETER GORDON JAMES E. MOORE II HARRY W. RICHARDSON 《Growth and change》2008,39(4):548-572
In previous research, the economic impacts of temporary shutdowns of the Los Angeles–Long Beach harbors were simulated after a hypothetical terrorist attack, applying the National Interstate Economic Model to estimate state‐by‐state as well as interindustry impacts. However, the unpredictable characteristic of terrorist attacks might not be applicable to the case of a ports shutdown such as the one caused by the lockout of September–October 2002. Market participants can be expected to have contingency plans based on anticipations of a strike or shutdown. Can we identify any of these in terms of the use of alternate ports, in terms of alternate modes or even alternate time periods? The purpose of this study is to examine these questions. The approach is elaborated by testing for the possible effects of trade diversion to other West Coast ports, transportation modes, and intertemporal substitutions. We use data from WISERTrade describing commodity‐specific trade for the major West Coast ports before, during, and after the 11‐day shutdown of the fall of 2002. Shippers’ ability to divert trade is a key ingredient in the economy's ability to withstand attacks and disruptions. The work estimates the impacts on 47 industrial sectors across 50 states (and the District of Columbia). 相似文献
222.
PETER T. KENDALL PHILIP M. SMITH DAVID W. HOLME 《The Journal of small animal practice》1982,23(9):538-554
Apparent digestibility and digestible energy (DE) content of 43 canned and 28 packeted samples of commercial cat foods were determined using panels of six adult domestic cats. Metabolizable energy (ME) content was also measured with 22 of the canned and 14 of the packeted foods. Mean apparent crude protein (CP), acid ether extract (AEE) and nitrogen-free extract (NFE) digestibility percentages of all foods (N = 71) were 78, 77 and 69. Apparent AEE and CP digestibility percentages increased in a curvilinear manner with intake; logarithmic regression curves explained 50 and 24 per cent of the variation in AEE and CP digestibility by intake. The use of modified Atwater factors over-estimated ME content of canned and packeted foods by 21 and 27 per cent respectively, compared with in vitro values. Twenty-one single or mulitple regression equations were generated predicting in-vivo DE or ME content of foods from laboratory analyses. The use of such equations in the practical definition of energy content of cat foods is discussed. 相似文献
223.
NADER SOLTANI CLARENCE J. SWANTON ALLAN S. HAMILL JOSHUA D. VYN PETER H. SIKKEMA 《Weed Biology and Management》2008,8(2):139-144
There is limited information on the effect of amitrole and 2,4-D ester applied preplant and pre-emergence in soybean (G lycine max L.) in Ontario, Canada. Six field trials were conducted over a 2 year period (2004 to 2005) at three Ontario locations to evaluate the response of soybean to amitrole or 2,4-D ester applied at 14 days preplant (DPP), 7 DPP, 1 day after planting (DAP), and 7 DAP. The application of amitrole resulted in as much as 5.8, 3.9, 1.7, and 1% visible crop injury in soybean at 7, 14, 28, and 56 days after emergence (DAE), respectively. There was no visible injury in soybean with any amitrole treatment at 56 DAE, except for amitrole applied at 7 DAP, which caused 1% visible injury in soybean at 2310 g ha−1 . The application of the 2,4-D ester caused ≤8.3, 9.7, 4.6, and 1.3% visible injury in soybean at 7, 14, 28, and 56 DAE, respectively. The visible injury decreased over time. There was no visible injury in soybean with any of the 2,4-D ester treatments at 56 DAE, except for the 2,4-D ester treatment applied at 7 DAP, which caused 1% visible injury at 1155 g ha−1 and 1.3% visible injury at 2310 g ha−1 . Soybean generally responded similarly to amitrole and 2,4-D ester when applied at 14 and 7 DPP; however, soybean was more tolerant to amitrole compared to 2,4-D ester when applied at 1 or 7 DAP. The application of amitrole and 2,4-D ester resulted in no biomass or yield reduction in soybean compared to the weed-free, untreated control at all doses and application timings evaluated. Soybean is tolerant to the preplant and pre-emergence application of amitrole or 2,4-D ester at the doses evaluated. 相似文献
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We tested the hypothesis that enhanced feeding success and survivorship of Arctic cod larvae in the Northeast Water polynya (Greenland Sea) are associated with high densities of their zooplankton prey in areas of low sea ice concentration. From late May to early August 1993, first-feeding yolk-sac larvae (6.5–8.5 mm long) were collected primarily along the coast and over shallow banks in the polynya, whereas post yolk-sac larvae (8.5–14 mm) were more uniformly dispersed over the sampling area. Arctic cod larvae < 14 mm fed almost exclusively on copepod nauplii (74% of total prey number) and copepod eggs (16%). Feeding success was defined as the residuals of the regression of the number of prey ingested against larval length. Nauplii density varied from 9600 to 731300 nauplii m-2(equivalent to 0.16 to 12.2 nauplii 1-1) but, contrary to our hypothesis, seldom limited the feeding success of Arctic cod larvae. Water temperature was the best predictor of feeding success in larvae of all sizes. First-feeding success and survivorship were low for larvae hatched before mid-July, and improved thereafter as surface temperatures increased in the open waters of the polynya. There was no relationship between feeding success and irradiance or wind. Assuming a fixed spawning season, it is concluded that a larger fraction of the newly hatched larvae would experience adequate temperatures in years when the polynya opens early. Based on this conclusion, we propose that the timing of the opening of polynyas is a critical determinant of year- class strength in Arctic cod, a key species in the Arctic food web. 相似文献