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41.
The incidence of haemangiomas was ascertained by questionnaire in infants born to 578 consecutive CVS patients and 445 consecutive mid-trimester amniocentesis patients seen at a single institution between 1 January 1989 and 31 May 1991. The incidence of 7·4 per cent reported in the amniocentesis group was comparable to previous estimates of the incidence of haemangiomas in the general population. In contrast, a 21·1 per cent incidence, three-fold higher than that observed in the amniocentesis group, was observed among CVS-exposed infants (P<0·001). This increased incidence was largely confined to patients undergoing a transcervical procedure. No correlation was observed between the incidence of haemangiomas and gestational age at sampling, sample size, number of sampling attempts, or a history of bleeding following the procedure. 相似文献
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Brad Gilmour Ted Huffman Andy Terauds Charles Jefferson 《Journal of Agricultural and Environmental Ethics》1996,9(1):16-41
The specific issue addressed in this paper is urban encroachment on agricultural lands, and the problems it poses for both analysis and the conservation of the land resource. The purpose of our discussion is two-fold: (1) to identify where and why traditional analytical and regulatory approaches fail to resolve land use conflicts, and (2) to explore ways and means of resolving some of the dilemmas which society faces in making land use decisions. This paper's contribution is in the spirit of Getting Incentives Right for the inter-temporal transfer of wealth, as represented in trade-offs between environmental and resource endowments and human and physical capital. Efforts are placed on identifying what the appropriate price, levy, taxes, and grant ratios ought to be in order to encourage individuals in the marketplace to act in society's interest. We have also explored ways of efficiently transmitting those incentives through the market mechanism, without unduly relying on bureaucratic methods or suasion. Emphasis is placed on mechanisms that have little scope for preferential access and are subject to public scrutiny; emphasis on such self-disciplining approaches should result in less effort expended on (unproductive) lobbying activities and bureaucratic administration.Brad Gilmour and Ted Huffman are Policy Analyst and Land Use Specialist respectively with Agriculture and Agri-food Canada. Andy Terauds and Charlie Jefferson are chairman and secretary respectively for the Ontario Institute of Agrologists Ottawa Branch Land Use Committee. This paper is intended to provoke thought and stimulate debate for input into the land use policy process and should not be seen as representing the views and policies of either Agriculture Canada or the Ontario Institute of Agrologists. 相似文献
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为准确了解内蒙古草原典型草地异戊二烯的排放状况 ,在 2 0 0 2和 2 0 0 3年观测实验的基础上 ,利用已有的经验模式和观测资料 ,计算了羊草样地 2 0 0 2和 2 0 0 3年生长季节异戊二烯的排放通量 .结果表明 :2 0 0 2和 2 0 0 3年异戊二烯排放具有明显的日、逐日、月、年变化 ,其排放通量首先依赖于可见光辐射 ,其次是温度 .2 0 0 2和 2 0 0 3年生长季羊草样地异戊二烯总排放 (以C计 )分别为 1 10 ,1 0 0g·m- 2 ,2 0 0 3年比 2 0 0 2年减少9 0 % .此现象主要是由于 2 0 0 3年可见光辐射减弱和气温降低造成的 .2 0 0 2和 2 0 0 3年生长季排放通量的最大值 (以C计 )分别为 2 3 3 2 0和193 3 8μg·m- 2 ·h- 1 ,当可见光辐射小时累计值小于 0 4MJ·m- 2 时 ,异戊二烯的排放通量一般为零 相似文献
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T. Brad Harris M. Teresa Cardador Michael S. Cole Sal Mistry Bradley L. Kirkman 《组织行为杂志》2019,40(4):456-471
Leadership scholars have yet to identify a clear and consistent relationship between leader conscientiousness and followers' satisfaction with a leader. Drawing from socioanalytic theory and related personality research, we argue that the underlying motives of leader conscientiousness can manifest in systematically different behaviors aimed at team task accomplishment, ranging from rigid and order‐driven to relatively more adaptable approaches. Importantly, we posit that the relationship between a leader's conscientiousness and adaptability is conditioned by role authenticity (i.e., the extent to which a leader believes a role permits expressions of her or his “true self”). Hence, we articulate a conditional indirect effects model whereby leader conscientiousness and leader role authenticity jointly predict leader adaptability and, in turn, increasing levels of leader adaptability are positively associated with followers' shared satisfaction with their leader. Data from a sample of fire and rescue crews provide partial support for the model. Post hoc analyses suggest that the conditioning influence of leader role authenticity on leader conscientiousness is more informative when subfacets of conscientiousness are considered. 相似文献
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Andrew Fry Brad Adams Kevin Davis Dave Swensen Shawn Munson William Cox 《International Journal of Greenhouse Gas Control》2011
Real-time electrochemical measurements of corrosion rate were performed to evaluate the respective corrosion rates of one boiler waterwall material (SA210) and three boiler superheater materials (T22, P91 and 347H) while firing Utah Western bituminous, Illinois high-sulfur bituminous and Powder River Basin (PRB) sub-bituminous coals in a 1.5 MW pulverized coal-fired furnace. The raw average measured corrosion rates were very low, between 0.0003 and 0.016 mm/year (0.012 and 0.63 mils/year) for most materials under air- and oxy-fired conditions. For some high-sulfur conditions measured corrosion rates were as high as 0.72 mm/year (28 mils/year). Waterwall corrosion rates decreased consistently when converting from air- to oxy-firing while superheater corrosion rates generally increased, although they were less than twice the air-fired rate under most conditions. Corrosion rates for the lower alloyed materials (SA210 and T22) increased significantly during transients from reducing to oxidizing conditions. Measured increases in the corrosion rate of 347H material under high sulfur and low temperature conditions, and associated decrease in corrosion rate at higher temperatures on this alloy, were consistent with the formation of trisulphates in the superheater deposits. The increase of corrosion rate with increased metal temperatures was demonstrated, as was the consistently repeatable nature of the observed results. 相似文献
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Male boreal toads (Bufo boreas) are thought to return to the breeding site every year but, if absent in a particular year, will be more likely to return the following year. Using Pollock's robust design we estimated temporary emigration (the probability a male toad is absent from a breeding site in a given year) at three locations in Colorado, USA: two in Rocky Mountain National Park and one in Chaffee County. We present data that suggest that not all male toads return to the breeding site every year. Our analyses indicate that temporary emigration varies by site and time (for example, from 1992 to 1998, the probability of temporary emigration ranged from 10% to 29% and from 3% to 95% at Lost Lake and Kettle Tarn, respectively). Although the results provide weak evidence that males are more likely to return after a year's hiatus, a general pattern of state-dependent temporary emigration was not supported. We also hypothesized relationships between temporary emigration and a number of weather variables. While some competitive models included weather covariates, imprecise and variable estimates of the effects of these covariates precluded fully defining their impact on temporary emigration. 相似文献
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