Reservoir Heterogeneity: Should It Be Modelled as Conformance or Dispersion?

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Meta-analysis of the origin of bimaturism in orangutan males

Unlike any other primate species, orangutans exhibit extraordinary sexual differences in their facial morphology. Two different strategies are available for males that reach sexual maturity: either become fully “flanged” and develop secondary sexual characteristics, which is knownto be only developed by the dominant male, or remain “unflanged” and not develop secondary sexual characteristics. The mechanism for how this bimaturism evolved and how occurs is poorly understood, but both flanged and unflanged males are reproductively successful. This project explores the physiological mechanism behind bimaturismin orangutan males; namely, are there genetic differences between flanged and unflanged males such that the strategy is inherited, is bimaturism a result of hormonal differences, and how do the two strategies influence reproductive success in male orangutans? Previous studies have shown that males that develop these “flanges” or cheek pads are more likely to have a high reproductive success than the ones who do not develop them. Results suggest that males with flanges emit a loud vocalization calls, also known as long calls, that give them higher opportunity for mates.https://scholarscompass.vcu.edu/uresposters/1257/thumbnail.jp

Random fields, large deviations and triviality in quantum field theory. Part I

The issue of the existence and possible triviality of the Euclidean quantum scalar field in dimension 4 is investigated by using some large deviations techniques. As usual, the field $\phi^{4}$ is obtained as a limit of regularized fields $\phi_{k}^{4}$ associated with a probability measures $\mu_{k,V}$, where $k, V$ represent ultraviolet and volume cutoffs. The result obtained is that in a fixed volume, the almost sure limit (as $k \rightarrow \infty$) of the density of $\mu_{k,V}$, with respect to the Gaussian free field measure, exists and is equal to $0$, provided that the coupling constant sequence is not vanishing. This implies that $\mu_{k,V}$ can not have a strong limit as the ultraviolet cutoff is removed. Furthermore, the normalization sequence $Z_{k,V}= E e^{-{\cal L}_{k,V}}$ is divergent as $k \rightarrow \infty$ for dimension 4 or greater. This leads to the non ultraviolet stability of the scalar quantum field in dimension 4 and tends to question its possible existence. In other cases, in particular, when the coupling is vanishing with a sufficiently high speed the limiting field is trivial. These assertions are also valid for vector fields and can be extended to polynomial Lagrangians

Flame retardancy and mechanical properties of poegmah compatibilized rice husk filled polypropylene composites

Flammability of Polypropylene, PP has restricted its usage as a versatile synthetic polymer. The addition of flame retardants will lower the flammability of PP. However, it will lower the mechanical properties. In this study, the flame retardancy of PP composite has been enhanced by the addition of intumescent flame retardant. Four formulations have been prepared, without flame retardant and with increasing concentration of flame retardant which are 20phr, 25phr and 30phr. The flammability of the composites has been measured using the Limiting Oxygen Index based on ASTM D2863. Two types of mechanical testing have been done to determine the mechanical properties, which are flexural test (ASTM D790) and impact test (ASTM D256). The thermal analysis has been done by thermogravimetry analysis (TGA) to determine the thermal stability of the composites prepared. Morphological study by scanning electron microscopy (SEM) has been done to study the filler distribution. Results obtained from the flammability test indicate that the addition of flame retardant has strongly improved the flame retardancy. The flexural strength and impact strength decreases as the concentration of flame retardant increases while the flexural modulus increases. The thermal analysis has proven that the composites with flame retardant have better thermal stability as compared to the composite without flame retardant. The morphological study has shown that the addition of flame retardant did not affect the filler distribution. The filler remain well distributed as the flame retardant introduced to the composites