Spatial and temporal distribution of Patched-related protein in the Drosophila embryo.
Patched-related (Ptr) encodes a protein with 12 potential transmembrane domains and a sterol-sensing domain that is closely related in predicted topology and domain organization to Patched, the canonical receptor of the Hedgehog pathway. Here we describe the production of an antibody specific for Drosophila Ptr and analyse its spatial and temporal distribution in the embryo. We find that at early developmental stages Ptr is predominantly localized at cell periphery but later on it becomes strongly and almost exclusively expressed in hemocytes. Interestingly Ptr null mutant embryos died without hatching. Our findings suggest that Ptr plays an essential function in Drosophila development, perhaps as a new receptor of embryonic hemocytes.
This study analyzes patent trends and volatilities for three heterogeneous quality patents in the Taiwan patent system from January 1973 to June 2006. The estimated models are symmetric GARCH and asymmetric EGARCH, providing full sample, rolling sample, and out-of-sample evidence. Three different patent types exhibit increasing trends, using monthly time series data from our samples. ”New design” patents also show time-varying volatility but other types of patents fail to reject the ARCH LM test. Findings show the asymmetric EGARCH model suitable for “new design” patent type through out of sample forecasts.