Reactions of recoil halogen atoms in liquid aqueous solutions of 5-bromouridine. Interaction and association of solutes and population distribution of associated species

Abstract. Witono JR, Usmadi D, Wihermanto, Purnomo DW, Safarinanugraha D, Pakiding Y, Netoseso N. 2020. Autecology of Drosera burmanni in the Wolobobo Botanic Gardens, Ngada District, Flores Island, Indonesia. Biodiversitas 21: 2137-2145. Drosera burmanni Vahl is a native carnivorous plant from tropical and subtropical Asia to the West Pacific, including Flores Island. During the botanical survey, a small population of the species was found in a limited area in the Wolobobo Botanic Gardens, Flores Island. Conservation of the species is necessary, since the habitat might be developed for the botanic gardens infrastructure. This research aims to study the autecology of D. burmanni, including environmental preferences and its associated species. Thirty plots with 2 x 2 m each were made to recognize its associated species and the pattern of its population distribution and its soil requirements. In the Wolobobo Botanic Gardens, D. burmanni flourishes with an average annual rainfall of 1835 mm; a temperature of 12.50-26.2° C; 48-99% humidity; at an altitude of 1489-1491 m asl.; a soil pH of 6.66, which contains very high C-organic, a high C/N ratio, moderate N total, K2O, P2O5, low CEC, and very low K, Na, Ca, Mg, and BS. Drosera burmanni displays a density of 8.5 individuals per m2 and is associated with 20 species, which belong to 19 genera and 9 families. The species has a clustering pattern and a positive association with Erigeron sumatrensis, Spinifex littoreus, and Imperata cylindrica. To conserve D. burmanni in the Wolobobo Botanic Gardens, it is necessary to designate its natural habitat as an in situ conservation area.

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Ultrathin frozen sections of yeast without aldehyde prefixation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081152 ◽

1978 ◽

Vol 36 (2) ◽

pp. 58-59

Author(s):

K. J. Böhm ◽

a. E. Unger

Keyword(s):

Aqueous Solutions ◽

Biological Material ◽

Yeast Cells ◽

Frozen Sections ◽

Good Preservation ◽

Ultrathin Frozen Sections

During the last years it was shown that also by means of cryo-ultra-microtomy a good preservation of substructural details of biological material was possible. However the specimen generally was prefixed in these cases with aldehydes.Preparing ultrathin frozen sections of chemically non-prefixed material commonly was linked up to considerable technical and manual expense and the results were not always satisfying. Furthermore, it seems to be impossible to carry out cytochemical investigations by means of treating sections of unfixed biological material with aqueous solutions.We therefore tried to overcome these difficulties by preparing yeast cells (S. cerevisiae) in the following manner:

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Imaging polymers, proteins and dna in aqueous solutions with the atomic force microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152136 ◽

1989 ◽

Vol 47 ◽

pp. 32-33

Author(s):

S.A.C. Gould ◽

B. Drake ◽

C.B. Prater ◽

A.L. Weisenhorn ◽

S.M. Lindsay ◽

...

Keyword(s):

Amino Acids ◽

Dna Sequencing ◽

Aqueous Solutions ◽

Atomic Force Microscope ◽

Piezoelectric Crystal ◽

Atomic Force ◽

Structure Of Molecules ◽

Optical Lever

The atomic force microscope (AFM) is an instrument that can be used to image many samples of interest in biology and medicine. Images of polymerized amino acids, polyalanine and polyphenylalanine demonstrate the potential of the AFM for revealing the structure of molecules. Images of the protein fibrinogen which agree with TEM images demonstrate that the AFM can provide topographical data on larger molecules. Finally, images of DNA suggest the AFM may soon provide an easier and faster technique for DNA sequencing.The AFM consists of a microfabricated SiO2 triangular shaped cantilever with a diamond tip affixed at the elbow to act as a probe. The sample is mounted on a electronically driven piezoelectric crystal. It is then placed in contact with the tip and scanned. The topography of the surface causes minute deflections in the 100 μm long cantilever which are detected using an optical lever.

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