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Spillways with breast walls are often used in such situations as increasing the regulating storage of flood discharge or disposing sediment from the reservoirs, etc. The hydraulic characteristics of the spillways with breast walls can be obtained by experimental, analytical and numerical methods. The aim of this study is to predict some characteristics of flow through the spillway with a breast wall with low and average-head operation using the numerical modeling along with some turbulence closure models. The experimental data were used to validate the numerical predictions. The results show that the RNG k-e and the standard k-e turbulence models can predict quite precisely some characteristics, such as the water surface, the discharge, and the vertical pressure distribution in comparison with the measured data. However, some errors occur on this pressure in the region nearby the crest boundary. Furthermore, the RNG k-e turbulence model performed more accurately than the standard k-e model as compared to the experimental data. Therefore, the RNG k-e turbulence model uses to properly validate the characteristics of the flow through spillway with a breast wall under various conditions, without recourse to expensive experimental procedures.

Surface water samples were collected from rivers which fed into large urban areas within Vietnam, Indonesia, Cambodia, and Thailand and were processed to enumerate Escherichia coli. Selected isolates were further characterized using PCR to detect the presence of specific virulence genes. Analyzing the four countries together, the approximate mean cfu/100 ml for E. coli counts in the dry season were log 4.3, while counts in the wet season were log 2.8. Of the 564 E. coli isolates screened for the presence of pathogenic genes, 3.9 % possessed at least one virulence gene. The most common pathogenic types found were Shiga toxin-producing E. coli isolates. These results reinforce the importance of monitoring urban surface waters for fecal contamination, that E. coli in these water environments may serve as opportunistic pathogens, and may help in determining the impact water usage from these rivers have on the public health of urban populations in Southeast Asia.

Tomographic probability representation is introduced for fermion fields. The states of the fermions are mapped onto the probability distribution of discrete random variables (spin projections). The operators acting on the fermion states are described by fermionic tomographic symbols. The product of the operators acting on the fermion states is mapped onto the star-product of the fermionic symbols. The kernel of the star-product is obtained. The antisymmetry of the fermion states is formulated as a specific symmetry property of the tomographic joint probability distribution associated with the states.

The tomographic approach to the quantum-scalar-field description is developed. Tomographic symbols of the field operators are introduced and their properties are studied. The star-product of the field operator symbols is considered. The relation to classical field theory is discussed.

The light-oxygen effect consists in a direct excitation of molecular oxygen dissolved in aqueous media of biosystems by the light; it provides the possibility to use lasers for therapeutic purposes. The wavelength of the used light should strictly correspond to the oxygen absorption bands. However, laser therapy also makes use of lasers emitting at 0.89 µm (outside the known oxygen bands), which suggests the action of a new photoreceptor. Here we argue that this mechanism of photoreception is a modification of the light-oxygen effect involving the absorption of photon simultaneously by the oxygen molecule and O-H stretch of the H20 molecule of liquid water.