Serial Elastic Elements in the Damselfly Wing: Mobile Vein Joints Contain Resilin

 Two main types of joints occur in the damselfly wing: mobile and immobile. Some longitudinal veins (RP2^–, RP3&4^–, and MP^–) are elastically joined with cross veins, whereas other longitudinal veins (IR1⁺, IR2⁺, MA⁺, CuA'⁺) are firmly joined with cross veins. In this study we mapped the distribution of serial elastic elements in the wing. The occurrence of resilin, a rubberlike protein, in mobile joints suggests that the automatic twisting mechanism of the leading edge by aerodynamic force works not by flexibility but by the elasticity of these joints. First, it should result in elastic energy storage in the distal areas of the wing. Second, serial elastic elements of wing presumably act as dampers of an aerodynamic force, which are responsible for gradual twisting of the leading edge. Received: 16 March 1999 / Accepted in revised form: 26 August 1999     

Exclusion of citrullinaemia in the first trimester of pregnancy by direct assay of argininosuccinate synthetase in chorionic villi

Citrullinaemia was presumed to be excluded in a fetus at risk by the direct assay of argininosuccinate synthetase in chorionic villi. The diagnosis was confirmed after amniocentesis by normal argininosuccinate synthetase activity in the cultured amniotic fluid cells and by a normal citrulline concentration in the amniotic fluid. The prediction of a normal fetus was confirmed at term by the birth of a non-citrullinaemic boy.     

Sequence analytical approach to the Upper Kimmeridgian-Lower Tithonian storm-dominated ramp deposits of the Boulonnais (Northern France). A landward time-equivalent to offshore marine source rocks

An interdisciplinary approach based on high-resolution physical stratigraphy, biostratigraphy, organic matter analysis and clay mineralogy has been applied to the mixed siliciclastic/carbonate Kimmeridgian/Tithonian deposits of the Boulonnais (north-western France). These rocks are the age-equivalents of some of the offshore marine source rocks of the North Sea and were deposited in an overall storm-dominated homoclinal ramp setting which may represent one of the most shore-proximal sediments of this age cropping out in north-western Europe. Comparison with data from the Yorkshire, Dorset, Lorraine and Aquitaine areas allows the discrimination of three major transgressive-regressive sediment packages with disconformities of interregional extent: (1) from the Baylei Zone to top Eudoxus Zone; (2) from the Autissiodorensis Zone to base Scitulus Zone; (3) from the upper Scitulus Zone to the Pectinatus Zone. The lower two regionally correlative disconformities correspond to the sequence boundaries at the top of the Eudoxus Zone and the top of the Autissiodorensis Zone, formed by high-frequency relative sea-level variations during the periods of maximum transgression of the platform. The latter disconformity (the P1 nodule bed) reflects a major tectonically induced reorganization of the north-west European intrashelf sedimentary basin, characterized by a shift in both the location of the main depocentre and the sources of sediment production.     

XII Ecdysone Workshop July 22–26, 1996 Barcelona,Spain

XII Ecdysone Workshop July 22–26, 1996 Barcelona, Spain