Recent work on a diverse array of echinoderm species has demonstrated, as is true in amphibians, that thyroid hormone (TH) accelerates development to metamorphosis. Interestingly, the feeding larvae of several species of sea urchins seem to obtain TH through their diet of planktonic algae (exogenous source), whereas nonfeeding larvae of the sand dollar Peronella japonica produce TH themselves (...

Previous research has shown that the temperature of underlying permafrost decreases after the ground surface is covered with sand. No significant conclusions have yet been drawn that explain why this happens, because the heat transfer mechanism effects of the sand layer on the underlying permafrost remain unclear. These mechanisms were studied in the present work. We found that the upward short...

In the evolution processes of wind blown sand movement and aeolian geomorphology, it always contains some complex behaviors, for example, the nonlinear character of turbulence and attractors, the stochastic character of wind gust, liftoff and movement of sand, the interaction among wind field, sand movement, electric field in wind blown sand flux and thermal diffusion, multi-scale character fro...

Straw checkerboard barrier (SCB) is the most representative antidesertification measure and plays a significant role in antidesertification projects. Large-eddy simulation and discrete-particle tracing were used to numerically simulate the wind sand movement inside the straw checkerboard barrier (SCB), study the movement characteristics of sand particles, find the transverse velocities of sand ...

The removal of microplastic from wastewater collected a plastic recycling facility was investigated, using laboratory scale sand-filter. Wastewater samples were before and after the onsite sand-filter, for characterization different polymer types, sizes, shapes. A considerable difference in characteristics concentrations microplastics observed sand-filtration, demonstrating differences source a...

We study the evolution of a one-dimensional pile, empty at rst, which receives a grain in its rst stack at each iteration. The nal position of grains is singular: grains are sorted according to their parity. They are sorted on trapezoidal areas alternating on both sides of a diagonal line of slope p 2. This is explained and proved by means of a local study. Each generated pile, encoded in heigh...

Background Establishment of sand flies laboratory colonies is essential to understand various biological aspects of Phlebotominae sand flies. The aims of the current study were to establish the colony of Phlebotomus sergenti Parrot (1917), the main vector of anthroponotic cutaneous leishmaniasis in old world, and to study biological parameters of this species. Methods The sand flies were rear...

The toxicity of trichloroethene (TCE) likely restricts microbial activity in close vicinity of a TCE dense nonaqueous phase liquid (DNAPL). This study examined the distribution of a dechlorinating community in relation to the distance from a TCE DNAPL using a diffusion-cell set-up. Subcultures of the KB-1(™) culture dechlorinating TCE to cis-dichloroethene and grown with either formate or lacta...

In this study, a set of nitrogen reduction strategies were modeled to evaluate the feasibility of improving water quality to meet total maximum daily loads (TMDLs) in two agricultural watersheds. For this purpose, a spatial-process model was calibrated and used to predict monthly nitrate losses (1994-96) from Sand and Bevens Creek watersheds located in south-central Minnesota. Statistical compa...