Biomass-derived thermal preparation of calcite, from phyto-capped marine gastropod shell, Turbinella pyrum L

2020 ◽  
Vol 31 (8) ◽  
pp. 3110-3119
Author(s):  
Rajathurai Shailaja ◽  
Govindasamy Tamilarasan ◽  
Kannabiran Parthasarathy ◽  
Sathiyarajeswaran Parameswaran
2004 ◽  
Vol 273 ◽  
pp. 163-172 ◽  
Author(s):  
C Martel ◽  
F Viard ◽  
D Bourguet ◽  
P Garcia-Meunier

2020 ◽  
Vol 39 (2) ◽  
pp. 419
Author(s):  
Yi Yang ◽  
Lu Qi ◽  
Lingfeng Kong ◽  
Qi Li
Keyword(s):  

2020 ◽  
Vol 17 (163) ◽  
pp. 20190721
Author(s):  
J. Larsson ◽  
A. M. Westram ◽  
S. Bengmark ◽  
T. Lundh ◽  
R. K. Butlin

The growth of snail shells can be described by simple mathematical rules. Variation in a few parameters can explain much of the diversity of shell shapes seen in nature. However, empirical studies of gastropod shell shape variation typically use geometric morphometric approaches, which do not capture this growth pattern. We have developed a way to infer a set of developmentally descriptive shape parameters based on three-dimensional logarithmic helicospiral growth and using landmarks from two-dimensional shell images as input. We demonstrate the utility of this approach, and compare it to the geometric morphometric approach, using a large set of Littorina saxatilis shells in which locally adapted populations differ in shape. Our method can be modified easily to make it applicable to a wide range of shell forms, which would allow for investigations of the similarities and differences between and within many different species of gastropods.


1957 ◽  
Vol 14 (7) ◽  
pp. 228-233
Author(s):  
V. V. Konovalov ◽  
V. I. Chechetkin ◽  
D. V. Zaliznyak ◽  
M. Ya. Firer
Keyword(s):  

1970 ◽  
Vol 119 (1) ◽  
pp. 39-47 ◽  
Author(s):  
Michiko Nishida-Fukuda ◽  
Fujio Egami

1. A multienzyme system capable of degrading keratosulphates to yield galactose, N-acetylglucosamine and sulphate was found in the liver extract of a marine gastropod, Charonia lampas. 2. During the degradation, neither oligosaccharides nor sulphated sugars were produced. 3. It is suggested that the degradation could be attributed to the concerted action of β-galactosidase, β-N-acetylglucosaminidase and a sulphatase (sulphohydrolase), tentatively designated keratosulphatase. 4. Two forms of keratosulphatase (I and II) were separated by DEAE-Sephadex column chromatography. Both forms could release all the sulphate from keratosulphates and neither appeared to be identical with glycosulphatase or chondrosulphatase, both of which are also present in Charonia lampas. 5. β-Galactosidase and β-N-acetylglucosaminidase could degrade keratopolysulphate to a greater extent in the presence of keratosulphatase than in its absence. 6. It is suggested that keratosulphate was first desulphated by the action of keratosulphatase, and the desulphated polymer was then degraded to galactose and N-acetylglucosamine by the action of β-galactosidase and β-N-acetylglucosaminidase. 7. β-Galactosidase alone released a small amount of galactose from shark cartilage keratopolysulphate, but β-N-acetylglucosaminidase alone did not release N-acetylglucosamine. This indicates that unsulphated galactose residues occupy all the non-reducing terminal positions in keratopolysulphate chains.


Sign in / Sign up

Export Citation Format

Share Document