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991.
992.
1. Pullets of 2 high-producing commercial stocks (both brown-egg layers) were exposed to 5 different lighting patterns between 18 and 72 weeks to test the hypothesis that photoperiods used in commercial lighting programmes early in the laying year may be unnecessarily long and, by accelerating the development of photorefractoriness, may contribute to the decline in egg production observed after the initial peak. Two rooms of 288 pullets were allocated to each treatment. 2. The rate of lay observed with a Step-Up treatment which gave increases in photoperiod from 8L:16D at 18 weeks to 15L:9D at 27 weeks of age was not significantly different from that of treatments which held the birds on 11L:13D during peak egg production but gave increments up to 15L:9D later in the laying year. 3. A control group maintained on 11L:13D from 20 to 72 weeks laid 295 eggs per bird housed and a further group held on 8L:16D from 0 to 72 weeks laid 284 eggs per bird. These yields were lower than the Step-Up treatment (299 eggs) but show the potential of modern hybrid stocks to lay prolifically even without light stimulation. 4. It is concluded that the stocks tested in this experiment showed no advantage when given lighting programmes in the first laying year which were designed to minimise the adverse effects of photorefractoriness. 相似文献
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The correction for attenuation due to measurement error (CAME) has received many historical criticisms, most of which can be traced to the limited ability to use CAME inferentially. Past attempts to determine confidence intervals for CAME are summarized and their limitations discussed. The author suggests that inference requires confidence sets that demarcate those population parameters likely to have produced an obtained value-rather than indicating the samples likely to be produced by a given population-and that most researchers tend to confuse these 2 types of confidence sets. Three different Monte-Carlo methods are presented, each offering a different way of examining confidence sets under the new conceptualization. Exploring the implications of these approaches for CAME suggests potential consequences for other statistics. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Zambia is well endowed with hydropower and other energy resources, which could facilitate production of electricity for both urban and rural areas of the country. The country has an installed electricity generation capacity of 1786 MW and undeveloped hydropower potential of over 6000 MW. In the last few years, demand has been growing and it is anticipated to outstrip supply in 2008. The load growth is attributed to increased mining activities and development of the industrial base. The country is also endowed with abundant natural resources such as arable land, water, minerals and wildlife. With the available resource base, electricity along with other social and economic infrastructure such as roads and telecommunications could facilitate increased economic activities. In rural areas, electricity could be used for crop irrigation, agro-processing, small-scale mining and to facilitate tourism. However, rural electrification (RE) faces many challenges such as long distances from existing power stations to targeted rural areas, low population densities, high poverty levels and low skills availability. These and other factors have contributed to continued low levels of access to electricity in rural areas of the country. 相似文献
998.
Galia Lavi Charles A. Dinarello Ron N. Apte Smadar Cohen 《Israel journal of chemistry》2005,45(4):457-464
A sustained delivery system for interleukin-1 receptor antagonist (IL-1Ra) may have great therapeutic and industrial potential due to the cytokine activity as an IL-1 inhibitor. Here, we investigated the capability of biodegradable polymeric microspheres to sustain the release and prolong the therapeutic efficacy of IL-1Ra. IL-1Ra was encapsulated within rapidly degrading poly(lactic/glycolic acid) PLGA RG502H microspheres, which showed a desirable release profile of IL-1Ra in vitro. Pharmacokinetic study in mice revealed elevated serum levels of the recombinant IL-1Ra (rIL-1Ra) for up to 8 days following subcutaneous injection of IL-1Ra microspheres. In comparison, the serum levels of rIL-1Ra following subcutaneous or intravenous bolus injection of the soluble cytokine decreased very rapidly; within 48 h no recombinant cytokine was detected in mice sera. The sustained delivery of rIL-1Ra for over two weeks was efficient in inhibiting IL-1ß-stimulated induction of serum IL-6. These results suggest that the present therapeutic protocol of daily bolus injections of the IL-1Ra may be replaced by a weekly injection of IL-1Ra within PLGA RG502H microspheres. 相似文献
999.
Charles W. Forsberg Daniel C. Stack Daniel Curtis Geoffrey Haratyk Nestor Andres Sepulveda 《The Electricity Journal》2017,30(6):42-52
The large-scale deployment of wind or solar energy results in electricity prices below the price of fossil fuels at times of high wind or solar output. Price collapse can be limited by using low-price electricity to heat firebrick to high temperatures, store the heat in firebrick, and provide hot air as needed to industrial furnaces, kilns, power plants and gas turbines. This sets a minimum price on electricity near that of fossil fuels. 相似文献
1000.
Jason Long Michael Smith Troy Schaum Charles Berman AmparoCasani Noah Shepherd 《城市环境设计》2014,(6):122-129
正AAP学院米尔斯坦堂是位于纽约州伊萨卡市久负盛名的康奈尔大学建筑艺术和规划学院(简称"AAP学院")近百年来新建的第一栋建筑。但新建筑并没有独立于学院原有建筑,而是设计为与原有建筑室内外各层面相接的综合体。约4 400m2的空间内包含了工作室、展廊、评图室以及第一个专属礼堂等学院特别需要的空间。学院原有的4栋建筑位于校园北部边 相似文献