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The use of small alternators, other than for standby purposes, is increasing and this has focused attention on the reliability and utility of the parameters normally quoted for such machines. Test procedures are described and methods used for parameter estimation discussed, with particular emphasis on the difficulties presented by small brushless machines  相似文献   
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The days ahead     
Noseworthy E  Gladding M  Wills J  Tindall C  Placides D  Sanford T  Sims L  Marshall D  Jones RM  Bayne D 《Food management》1991,26(7):118-20, 122, 124 passim
How are government controls affecting healthcare foodservices?Are growing elderly & outpatient populations changing foodservices' missions. What are the hottest trends? As members of the American Society for Hospital Food Service Administrators prepared for their annual meeting in Orlando, FM queried 11 Southeastern directors to learn their most pressing concerns & how they are positioning their departments for the future.  相似文献   
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This review draws attention to the need for consolidated inquiry into large‐scale consular emergency management. Occurring outside national borders, these low‐probability but high‐impact events affect a large number of national citizens. They challenge governments' crisis management systems, and direct public and government attention to a sector that has been largely overlooked in public administration literature – consular affairs. This review brings together the relevant literature on consular assistance and looks further afield to find analysis of emergency responses in case studies of three major consular emergencies. Three underlying themes emerge, central to a more nuanced understanding of the government response to large‐scale emergencies affecting citizens abroad.  相似文献   
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1‐Alkynylcyclopropyl tosylates react with alkylmagnesium halides in the presence of catalytic ferric acetylacetonate [Fe(acac)3] under net propargylic substitution; allene formation, which is the prevalent reactivity mode of propargylic substrates otherwise, was noticed as a side reaction only when branched alkyl‐ or aryl‐Grignard reagents were used. These transformations represent the first successful iron‐catalyzed cross‐coupling reactions of tert‐alkyl electrophiles.

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The human DNA mismatch repair genes hMSH2 and hMSH6 encode the proteins that, together, bind to mismatches to initiate repair of replication errors. Human tumor cells containing mutations in these genes have strongly elevated mutation rates in selectable genes and at microsatellite loci, although mutations in these genes cause somewhat different mutator phenotypes. These cells are also resistant to killing by certain drugs and are defective in mismatch repair. Because the elevated mutation rates in these cells may lead to mutations in additional genes that are causally related to the other defects, here we attempt to establish a cause-effect relationship between the hMSH2 and hMSH6 gene mutations and the observed phenotypes. The endometrial tumor cell line HEC59 contains mutations in both alleles of hMSH2. The colon tumor cell line HCT15 contains mutations in hMSH6 and also has a sequence change in a conserved region of the coding sequence for DNA polymerase delta, a replicative DNA polymerase. We introduced human chromosome 2 containing the wild-type hMSH2 and hMSH6 genes into HEC59 and HCT15 cells. Introduction of chromosome 2 to HEC59 cells restored microsatellite stability, sensitivity to N-methyl-N'-nitro-N-nitrosoguanidine treatment, and mismatch repair activity. Transfer of chromosome 2 to HCT15 cells also reduced the mutation rate at the HPRT locus and restored sensitivity to N-methyl-N'-nitro-N-nitrosoguanidine treatment and mismatch repair activity. The results demonstrate that the observed defects are causally related to mutations in genes on chromosome 2, probably hMSH2 or hMSH6, but are not related to sequence changes in other genes, including the gene encoding DNA polymerase delta.  相似文献   
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A method of computer-aided design and optimization of induction motors is proposed. The method uses the digital computer in an interactive mode; the objective is the best use of man and machine. A definition of a 'good' design is attempted and the resulting ramifications discussed.  相似文献   
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