The structure of biological membranes. Current status

1972 ◽  
Vol 129 (2) ◽  
pp. 202-228 ◽  
Author(s):  
J. D. Robertson
2013 ◽  
Vol 9 (1) ◽  
pp. 86-98 ◽  
Author(s):  
Dragan Cvetkovic ◽  
Leszek Fiedor ◽  
Anna Wisniewska-Becker ◽  
Dejan Markovic

2012 ◽  
Vol 9 (1) ◽  
pp. 86-98 ◽  
Author(s):  
Dragan Cvetkovic ◽  
Leszek Fiedor ◽  
Anna Wisniewska-Becker ◽  
Dejan Markovic

2012 ◽  
Vol 9 (1) ◽  
pp. 86-98
Author(s):  
Dragan Cvetkovic, , , ◽  
Leszek Fiedor ◽  
Anna Wisniewska-Becker ◽  
Dejan Markovic

1966 ◽  
Vol 25 ◽  
pp. 266-267
Author(s):  
R. L. Duncombe

An examination of some specialized lunar and planetary ephemerides has revealed inconsistencies in the adopted planetary masses, the presence of non-gravitational terms, and some outright numerical errors. They should be considered of temporary usefulness only, subject to subsequent amendment as required for the interpretation of observational data.


Author(s):  
S.W. Hui ◽  
D.F. Parsons

The development of the hydration stages for electron microscopes has opened up the application of electron diffraction in the study of biological membranes. Membrane specimen can now be observed without the artifacts introduced during drying, fixation and staining. The advantages of the electron diffraction technique, such as the abilities to observe small areas and thin specimens, to image and to screen impurities, to vary the camera length, and to reduce data collection time are fully utilized. Here we report our pioneering work in this area.


Author(s):  
Neng-Bo He ◽  
S.W. Hui

Monolayers and planar "black" lipid membranes have been widely used as models for studying the structure and properties of biological membranes. Because of the lack of a suitable method to prepare these membranes for electron microscopic observation, their ultrastructure is so far not well understood. A method of forming molecular bilayers over the holes of fine mesh grids was developed by Hui et al. to study hydrated and unsupported lipid bilayers by electron diffraction, and to image phase separated domains by diffraction contrast. We now adapted the method of Pattus et al. of spreading biological membranes vesicles on the air-water interfaces to reconstitute biological membranes into unsupported planar films for electron microscopic study. hemoglobin-free human erythrocyte membrane stroma was prepared by hemolysis. The membranes were spreaded at 20°C on balanced salt solution in a Langmuir trough until a surface pressure of 20 dyne/cm was reached. The surface film was repeatedly washed by passing to adjacent troughs over shallow partitions (fig. 1).


Author(s):  
Martin Peckerar ◽  
Anastasios Tousimis

Solid state x-ray sensing systems have been used for many years in conjunction with scanning and transmission electron microscopes. Such systems conveniently provide users with elemental area maps and quantitative chemical analyses of samples. Improvements on these tools are currently sought in the following areas: sensitivity at longer and shorter x-ray wavelengths and minimization of noise-broadening of spectral lines. In this paper, we review basic limitations and recent advances in each of these areas. Throughout the review, we emphasize the systems nature of the problem. That is. limitations exist not only in the sensor elements but also in the preamplifier/amplifier chain and in the interfaces between these components.Solid state x-ray sensors usually function by way of incident photons creating electron-hole pairs in semiconductor material. This radiation-produced mobile charge is swept into external circuitry by electric fields in the semiconductor bulk.


2021 ◽  
Author(s):  
Yuanhong Ma ◽  
Shao-Jie Lou ◽  
Zhaomin Hou

This review article provides a comprehensive overview to recognise the current status of electron-deficient boron-based catalysis in C–H functionalisations.


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