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101.
A new optical instrument, the liquid crystal point diffraction interferometer (LCPDI), is used to measure the temperature distribution across a heated chamber filled with silicone oil. Data taken using the LCPDI are compared to equivalent measurements made with a traversing thermocouple and the two data sets show excellent agreement. This instrument maintains the compact, robust design of Linnik's point diffraction interferometer and adds to it phase stepping capability for quantitative interferogram analysis. The result is a compact, simple to align, environmentally insensitive interferometer capable of accurately measuring optical wavefronts with very high data density and with automated data reduction. 相似文献
102.
103.
"Know thyself"-Delphic OracleThree surveys conducted in 1965 have produced data on employment in operational research. This has been analysed to throw light on the growth in various types of organization and sizes of operational research groups. The mobility of those in their first and subsequent jobs is also studied. Reasons which people give for changing their jobs are given. The position of women in operational research is compared with that of men. 相似文献
104.
The short-term relationship between the sales of consumer durables by a chain of retail outlets and the amount of variety is determined by two different methods. One method uses the sales lost because of non-availability and the other uses sales assistants' subjective estimates of the probability of selling purchasers an alternative brand if the one bought was unavailable. The two techniques are compared and the implications of the results for inventory policies are indicated. 相似文献
105.
A competitive bidding policy can be formulated if prior probability distributions of competitors' bids for future contracts have been determined. A method for determining these prior probability distributions is described for markets where there are a large number of customers. The identity of each winning company and its bid are assumed to be available to competitors and other customers so that the market reacts quickly to changes. A real example of the use of the method is given. The suppliers' general levels of bidding and their variation with individual types of customer are evaluated quantitatively. The results are consistent with qualitative knowledge of the market. 相似文献
106.
Long noncoding RNAs in neuronal-glial fate specification and oligodendrocyte lineage maturation 总被引:1,自引:0,他引:1
Tim R Mercer Irfan A Qureshi Solen Gokhan Marcel E Dinger Guangyu Li John S Mattick Mark F Mehler 《BMC neuroscience》2010,11(1):14
Background
Long non-protein-coding RNAs (ncRNAs) are emerging as important regulators of cellular differentiation and are widely expressed in the brain. 相似文献107.
The mass spectra of six β-ketoalkylidenephosphoranes have been examined. The spectra all exhibit an electron-impact induced migration of oxygen to phosphorus reminiscent of their thermal decomposition. 相似文献
108.
109.
Maria?Sievertzon Valtteri?Wirta Alex?Mercer Konstantinos?Meletis Rikard?Erlandsson Lilian?Wikstr?m Jonas?Frisén Joakim?LundebergEmail author 《BMC neuroscience》2005,6(1):28
Background
Neural stem cells (NSCs) can be isolated from the adult mammalian brain and expanded in culture, in the form of cellular aggregates called neurospheres. Neurospheres provide an in vitro model for studying NSC behaviour and give information on the factors and mechanisms that govern their proliferation and differentiation. They are also a promising source for cell replacement therapies of the central nervous system. Neurospheres are complex structures consisting of several cell types of varying degrees of differentiation. One way of characterising neurospheres is to analyse their gene expression profiles. The value of such studies is however uncertain since they are heterogeneous structures and different populations of neurospheres may vary significantly in their gene expression. 相似文献110.
Maria?Sievertzon Valtteri?Wirta Alex?Mercer Jonas?Frisén Joakim?LundebergEmail author 《BMC neuroscience》2005,6(1):55