摘要:

SYNOPSISA technique is described for using evaporated carbon films in the preparation of pseudo‐replicas that can be employed for both electron microscopy and electron diffraction. The areas selected microscopically for diffraction can be as small as one square micron. Fluorescent X‐ray analyses can frequently be carried out on the same preparations.The procedure is illustrated from current investigations of tooth enamel and with pseudo‐replicas from a variety of other s

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00429.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

SYNOPSISRadial striations are shown to be present as fixed appearances in the refraction rings of submerged bubbles in diverse media, and to be due to aerosol particles at the surface. They are shown to be of multiple origin, being composed of brighter parts of concentric rings of light which may be produced in this usually dark zone. Possible causes of these phenomena are discussed in relation to the bubble surface. It is concluded that the bubbles are surrounded by thin layers of static material of different refractive index from the bulk of the liquid, and that the “radial striations” are due to multiple image formation by the two interfaces produ

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00430.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

SYNOPSISThis culture chamber is a development of an older model, embodying the same principle of growth on a cellophane membrane. Organisms can be observed by vertical or transmitted illumination, with or without phase contrast, and can be stainedin situ.

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00431.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

SYNOPSISBacteria from the stomachs of sheep have been examined by direct ultra‐violet and ultra‐violet negative phase‐contrast micrographs. These micrographs show details in the rumen organisms which were poorly or not received by visual light methods. In the abomasum, the acid‐stomach of the sheep, signs of disorganization and disintegration of the bacteria were evident. Material which absorbed strongly in 2749 Å. wavelength was often seen to be concentrated at the edge of the. cells and sometimes in internal granules in the cells in the abomasum. Loss in rigidity and rupture of the cell walls were also often seen in these cells. Some of these degenerative changes appeared to start in the omasum of the sheep. In the rumen the presence of strongly absorbing material outside the cell membranes in some bacteria was marked. In some cases it took the form of a fringe; in others it crept between the septa dividing two units as an apparently homogeneo

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00432.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

SYNOPSISThe surfaces of bacteria and similar organisms cannot be satisfactorily studied in the electron microscope because of the excessive mass thickness of the cells. The paper describes an adaptation of the carbon replica technique, which enables a surface examination to be carried out. Artifacts, which are often present when cells are examined directly, are even more apparent in replica studies. The nature and origin of these artifacts is fully discussed.The replica technique is applied to a surface study ofSaccharomyces cerevisiæ.By examining micrographs of replicas of budding scars and also of cells at various stages of division, it is possible to build up a plausible picture of the whole division process

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00433.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

SYNOPSISThe type specimens ofNavicula maculosaDonkin andNavicula albinensisGrunow have been examined and the species are shown to be synonymous.Navicula maculosaDonkin in Peragallo, Diatomées marines de France, 1897–1908, is a misidentification and this species has been renam

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00434.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY

摘要:

SYNOPSISA compressor for holding live insects under a dissecting microscope is described.

ISSN:0368-3974    

DOI:10.1111/j.1365-2818.1955.tb00435.x

出版商:Blackwell Publishing Ltd    

年代:1955

数据来源: WILEY