GREGOR M1 mirror and cell design: effects of different mirror substrates on the telescope design

1972 ◽

Vol 30 ◽

pp. 570-571

Author(s):

J. R. Sellar ◽

J. M. Cowley

Keyword(s):

Solid Material ◽

Cell Design ◽

Current Interest ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Transmission Electron ◽

Environmental Cell ◽

Scanning Transmission ◽

Conventional Transmission Electron Microscope ◽

Transmission Microscope

Current interest in high voltage electron microscopy, especially in the scanning mode, has prompted the development of a method for determining the contrast and resolution of images of specimens in controlled-atmosphere stages or open to the air, hydrated biological specimens being a good example. Such a method would be of use in the prediction of microscope performance and in the subsequent optimization of environmental cell design for given circumstances of accelerating voltage, cell gas pressure and constitution, and desired resolution.Fig. 1 depicts the alfresco cell of a focussed scanning transmission microscope with a layer of gas L (and possibly a thin window W) between the objective O and specimen T. Using the principle of reciprocity, it may be considered optically equivalent to a conventional transmission electron microscope, if the beams were reversed. The layer of gas or solid material after the specimen in the STEM or before the specimen in TEM has no great effect on resolution or contrast and so is ignored here.

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Design-Effects in Prospective and Retrospective Memory for Actions

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027//1618-3169.50.1.4 ◽

2003 ◽

Vol 50 (1) ◽

pp. 4-15 ◽

Cited By ~ 15

Author(s):

Petra Jahn ◽

Johannes Engelkamp

Keyword(s):

Prospective Memory ◽

Memory Task ◽

Prospective Memory Task ◽

Retrospective Memory ◽

Ample Evidence ◽

Relational Information ◽

Design Effects ◽

Verbal Tasks ◽

Within Subjects

There is ample evidence that memory for action phrases such as “open the bottle” is better in subject-performed tasks (SPTs), i.e., if the participants perform the actions, than in verbal tasks (VTs), if they only read the phrases or listen to them. It is less clear whether also the sole intention to perform the actions later, i.e., a prospective memory task (PT), improves memory compared with VTs. Inconsistent findings have been reported for within-subjects and between-subjects designs. The present study attempts to clarify the situation. In three experiments, better recall for SPTs than for PTs and for PTs than for VTs were observed if mixed lists were used. If pure lists were used, there was a PT effect but no SPT over PT advantage. The findings were discussed from the perspective of item-specific and relational information.

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