The purpose of this study is to examine the initial reaction of craniofacial complex to the traction of headgears which are frequent used in clinical practice by using holographic interference method. Changes In the fringe pattern according to the traction conditions (outer bow length, load amount, direction) were compared. Human dry skull was used as experimental material, the results were as follows. 1. The density of fringes Increased with an increase in load. 2. Maxillary headgear affected circummaxillary bones-temporal bone, zygomatic bone, nasal bone, frontal bone, sphenoid bone as well as maxilla. 3. The most upward-backward displacement was observed in a high pull head gear (30degrees), this is though to be a optimal direction for supressing the growth of the maxilla.
Frontal Bone ; Head ; Holography* ; Humans ; Maxilla ; Nasal Bone ; Skull ; Sphenoid Bone ; Traction*

AIMTo study the quantitative structure-activity relationship ( QSAR) of 23 tetrahydroimidazobenzodiazepinone (TIBO) as anti-HIV drug.

METHODSA newly developed three-dimensional holographic vector of atomic interaction field (3D-HoVAIF) was used to describe the chemical structure of anti-HIV drug-23 TIBO, a partial least square regression (PLS) model was built.

RESULTSThe obtained model with the cumulative multiple correlation coefficient (Rcum(2)), cumulative cross-validated (Qcum(2)) and standard error of estimation (SD) were Rcum(2) = 0. 824, Qcum(2) = 0.778 and SD = 0.56, respectively. The model had favorable estimation stability and good prediction capabilities.

CONCLUSIONSatisfactory results showed that 3D-HoVAIF with definite physic-chemical meanings and easy structural interpretation for structural characterization could preferably express information related to biological activity of TIBO.

Algorithms ; Anti-HIV Agents ; chemistry ; Benzodiazepines ; chemistry ; Holography ; methods ; Imidazoles ; chemistry ; Models, Molecular ; Quantitative Structure-Activity Relationship