Converting non-Mesogenic to Mesogenic Stacking of Amino--Triazine-Based Dendrons with -CN Phenyl Unit by Eliminating Peripheral Dipole.

Three new amino--triazine-based dendrons, , , and , containing an aryl-CN moiety in the dendritic skeleton were prepared in 72-81% yields (: R = - N(-CH), R = -OCH, : R = R = - N(-CH), : R = - N(-CH), R = - N(-CH)). Dendrons with N(-CH) and -OCH peripheral substituents, surprisingly, did not show any mesogenic phase during the thermal process. However, non-mesogenic can be converted to mesogenic or by eliminating the peripheral dipole arising from the alkoxy substituent; dendron only comprising the same N(-CH) peripheral groups showed a ~25 °C mesogenic range on heating and ~108 °C mesogenic range on cooling.

Clinical manifestations of parainfluenza infection in children.

Parainfluenza viruses are major pathogens causing respiratory illness, manifesting from mild upper respiratory tract infection to bronchiolitis and pneumonia. This retrospective study aimed at providing clinical and epidemiologic data addressing the parainfluenza virus infection in Taiwan. A total of 39 patients were enrolled in this study from March 1999 to December 2000.