The effects of temperature on extracted teeth of different age groups: A pilot study.

Context: Type of dentition and age related changes may affect the behavior of dental hard tissues under thermal stress.

Aim: This study was conducted to analyze the effects of varying temperatures on extracted teeth of different age groups in a simulated laboratory set up.

Settings And Design: Experimental pilot study.

Light fluence rate and chloroplasts are sources of signals controlling mesophyll cell morphogenesis and division.

As part of the acclimation of the photosynthetic apparatus to high fluence rates of light, mesophyll (photosynthetic) leaf cells change in morphology (they elongate anticlinally or perpendicular to the leaf surface) and undergo extra cell divisions. This results in increased leaf thickness and internal, protective shading among chloroplasts. Here we have examined whether the chloroplasts themselves are sources of intracellular signals that trigger these changes, by monitoring the Arabidopsis thaliana chm1 variegated mutant, in which albino (chloroplast-defective) and green (with functional chloroplasts) sectors coexist in one leaf.