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Flexible-shelled eggs of common snapping turtles (Chelydra serpentina) were incubated on two substrates (sand and vermiculite) at each of three temperatures (26.0°, 28.SO, 31.0°C) and three moisture regimes (water potentials initially -150 kPa, -550 kPa, -950 kPa) in a factorial experiment assessing the influence of these variables on the water relations of eggs and the development of embryos.Hatching success was high on wet substrates at 26.0° and 28.5°, but declined at the highest temperature and on drier media. Net absorption of water by viable eggs, duration of incubation by embryos, and size of hatchlings were positively correlated with wetness of substrates and negatively correlated with temperature. Turtles hatching from eggs at 26.0° were males regardless of the wetness of the medium, whereas those emerging from eggs at 28.5° and 31.0° were females. These patterns of response characterized eggs incubated on sand as well as those on vermiculite.Findings from this study indicate that temporal and spatial variations in moisture and temperature within and among natural nests probably elicit ecologically important variation in size and sex of hatchling snapping turtles.

Oral irrigation with water for 14 days had an improved therapeutic benefit for AP over that of routine oral hygiene alone and this improvement was accompanied by a down-modulation of the pro-inflammatory cytokine profile in GCF.

Several attempts have been made in recent years to formulate a general explanation for what appear to be recurring patterns of allometric variation in morphology, physiology, and ecology of both plants and animals (e.g. the Metabolic Theory of Ecology, the Allometric Cascade, the Metabolic-Level Boundaries hypothesis). However, published estimates for parameters in allometric equations often are inaccurate, owing to undetected bias introduced by the traditional method for fitting lines to empirical data. The traditional method entails fitting a straight line to logarithmic transformations of the original data and then back-transforming the resulting equation to the arithmetic scale. Because of fundamental changes in distributions attending transformation of predictor and response variables, the traditional practice may cause influential outliers to go undetected, and it may result in an underparameterized model being fitted to the data. Also, substantial bias may be introduced by the insidious rotational distortion that accompanies regression analyses performed on logarithms. Consequently, the aforementioned patterns of allometric variation may be illusions, and the theoretical explanations may be wide of the mark. Problems attending the traditional procedure can be largely avoided in future research simply by performing preliminary analyses on arithmetic values and by validating fitted equations in the arithmetic domain. The goal of most allometric research is to characterize relationships between biological variables and body size, and this is done most effectively with data expressed in the units of measurement. Back-transforming from a straight line fitted to logarithms is not a generally reliable way to estimate an allometric equation in the original scale.