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排序方式: 共有193条查询结果,搜索用时 31 毫秒
1.
合成了12种PAMAMSA(1~6G) M(PAMAM为聚酰胺 胺,SA为水杨醛,G为代数,M分别为Fe3 ,Co2 离子)树枝状高分子催化剂.在101 325kPa、70℃和无溶剂条件下,这些催化剂对环己烯分子氧氧化反应的催化效果良好.反应以7 氧杂二环[4,1,0]己烷(1),2 环己基 1 醇(2),2 环己基 1 酮(3)和7 氧杂二环[4,1,0]己烷 2 酮(4)为主要产物.其中产物7 氧杂二环[4,1,0]己烷 2 酮(4)为此类氧化反应中首次报道的新产物. 相似文献
2.
运用选择、投影、广义笛卡尔积等关系代数运算 ,给出了遗传算法的搜索空间及个体、遗传算子和搜索最优解过程等关系代数形式的描述 ,建立了遗传算法的关系代数模型 ,给出了遗传算法的数学解释 .然后 ,给出建立遗传算法关系代数模型的意义 ,说明了数据挖掘和知识发现应用于遗传算法的可行性 .最后 ,用该模型描述了 2个常见用遗传算法解决的问题 ,即TSP问题和交互式遗传算法中的服装设计问题 ,结果表明该模型的可行性 . 相似文献
3.
在分析微机械陀螺仪静电力反馈检测结构的基础上,提出了一种对现有Sigma-Delta静电力反馈检测方式的改进设计.对微机械陀螺仪闭环检测系统进行了离散化处理.基于Lyapunov稳定性原理,构造了一类能够使系统有限时间稳定的输出反馈控制器,并对其鲁棒性能进行了分析.该电路系统在Cadence平台下使用AMS 0.35 ... 相似文献
4.
This paper investigates potential invariance of mean forecast errors to structural breaks in the data generating process. From the general forecasting literature, such robustness is expected to be a rare occurrence. With the aid of a stylized macro model we are able to identify some economically relevant cases of robustness and to interpret them economically. We give an interpretation in terms of co‐breaking. The analytical results resound well with the forecasting record of a medium‐scale econometric model of the Norwegian economy. 相似文献
5.
Geir Hestmark 《Annals of science》2013,70(4):262-281
Scottish publisher and naturalist Robert Chambers pursued an amateur interest in geology through much of his life. His early measurements of raised beaches in Scotland earned him membership in the Geological Society of London in 1844, a recognition much appreciated by the anonymous author of the ‘scandalous’ Vestiges published the same year. Although familiar with emerging ice age theories, Chambers remained with most British geologists a sceptic through the 1840s, even after a trip to the glaciers of the Alps in 1848, which nevertheless prepared him for the turning point, which came in 1849 during an extensive field trip in Norway and Sweden. Here a wealth of observations left him in no doubt that vast glaciers had formerly covered Scandinavia, polishing cliffs, scouring striations, depositing old moraines and erratic boulders. This also led him to a new glacial reading of the British landscape, and with the ardent conviction of a fresh convert he became one of the most vocal supporters of glacial theory in Britain in the 1850s at a time when the iceberg drift theory for boulder transport was still favoured by most prominent British geologists. While Chambers through his popular Chambers’s Edinburgh Journal communicated his travels and ice age vision to a wide audience, and also pointed out ice age evidence on guided excursions around Edinburgh, he did not enter this new vision into subsequent editions of Vestiges, probably in order not to reveal its author. This paper explores Chambers’s contributions to the ice age debate, his field trips and the genesis of his convictions, and evaluates his impact on the scientific debate. 相似文献
6.
Macgregor S Montgomery GW Liu JZ Zhao ZZ Henders AK Stark M Schmid H Holland EA Duffy DL Zhang M Painter JN Nyholt DR Maskiell JA Jetann J Ferguson M Cust AE Jenkins MA Whiteman DC Olsson H Puig S Bianchi-Scarrà G Hansson J Demenais F Landi MT Dębniak T Mackie R Azizi E Bressac-de Paillerets B Goldstein AM Kanetsky PA Gruis NA Elder DE Newton-Bishop JA Bishop DT Iles MM Helsing P Amos CI Wei Q Wang LE Lee JE Qureshi AA Kefford RF Giles GG Armstrong BK Aitken JF Han J Hopper JL Trent JM Brown KM 《Nature genetics》2011,43(11):1114-1118
We performed a genome-wide association study of melanoma in a discovery cohort of 2,168 Australian individuals with melanoma and 4,387 control individuals. In this discovery phase, we confirm several previously characterized melanoma-associated loci at MC1R, ASIP and MTAP-CDKN2A. We selected variants at nine loci for replication in three independent case-control studies (Europe: 2,804 subjects with melanoma, 7,618 control subjects; United States 1: 1,804 subjects with melanoma, 1,026 control subjects; United States 2: 585 subjects with melanoma, 6,500 control subjects). The combined meta-analysis of all case-control studies identified a new susceptibility locus at 1q21.3 (rs7412746, P = 9.0 × 10(-11), OR in combined replication cohorts of 0.89 (95% CI 0.85-0.95)). We also show evidence suggesting that melanoma associates with 1q42.12 (rs3219090, P = 9.3 × 10(-8)). The associated variants at the 1q21.3 locus span a region with ten genes, and plausible candidate genes for melanoma susceptibility include ARNT and SETDB1. Variants at the 1q21.3 locus do not seem to be associated with human pigmentation or measures of nevus density. 相似文献
7.
Alemu EA Sjøttem E Outzen H Larsen KB Holm T Bjørkøy G Johansen T 《Cellular and molecular life sciences : CMLS》2011,68(11):1953-1968
The protein kinase C (PKC) family of serine/threonine kinases consists of ten different isoforms grouped into three subfamilies,
denoted classical, novel and atypical PKCs (aPKCs). The aPKCs, PKCι/λ and PKCζ serve important roles during development and
in processes subverted in cancer such as cell and tissue polarity, cell proliferation, differentiation and apoptosis. In an
effort to identify novel interaction partners for aPKCs, we performed a yeast two-hybrid screen with the regulatory domain
of PKCι/λ as bait and identified the Krüppel-like factors family protein TIEG1 as a putative interaction partner for PKCι/λ.
We confirmed the interaction of both aPKCs with TIEG1 in vitro and in cells, and found that both aPKCs phosphorylate the DNA-binding
domain of TIEG1 on two critical residues. Interestingly, the aPKC-mediated phosphorylation of TIEG1 affected its DNA-binding
activity, subnuclear localization and transactivation potential. 相似文献
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Norway’s work life is known for its strong emphasis on the collaboration between employees, unions and managers. This article explores two case studies: two companies who are part of the same group of companies with the same owners, who are introducing broad collaboration. The same process was used to change employees’ participation in the development processes, but the results were different for each company. In this article we explore the factors that influence the implementation of broad collaboration between employees, unions and managers in the light of the Norwegian work life model and of the regional traditions. When introducing new collaboration patterns between managers, union and employees in a company, it is important to take regional traditions into consideration. One of the companies succeeded in implementing direct manager-employee collaboration, and the other company failed to implement broad collaboration. This article explores the reasons behind the different results. It further explores the experience from the two cases, and asks the question is the Norwegian work life model suited for all? The article suggests strategies for how to create an environment for broad collaboration in companies that have no such tradition. 相似文献