This research describes the goals, design and implementation of a quasi natural gradient, laboratory scale, sand tank (aquifer) model experiment. The model was used to study the transport of an inorganic tracer (Chloride) in groundwater, within a tropical aquifer (porous medium) material. Three-dimensional sand tank (1.8 m × 0.3 m × 0.8 m) experiments were conducted to investigate contaminant t...

It is routine to demonstrate in the exchange economy framework that small changes of individual preferences and endowments always result in small changes of the derived excess demand functions as one should expect. Though being as desirable for reasons of the consistency of the whole approach, however, a precise proof of the converse direction so far is still open to question. The present paper...

This paper studies competitive equilibria in economies characterized by the presence of asymmetric information, where non-exclusive contracts are traded on competitive markets and agents may be privately informed over their payoff. For such economies competitive equilibria may not exist when contracts trade at linear prices. We show that (non-trivial) competitive equilibria exist, under general...

OBJECTIVE To examine mechanisms controlling the stapedial reflex in patients with amyotrophic sclerosis (ALS). METHODS The stapedial reflex was examined using impedance audiometry in 38 patients with sporadic ALS and in 25 age matched controls. RESULTS All patients showed normal reflex decay test results. There were no significant differences between patients with ALS and control subjects i...

Limited Attention as the Scarce Resource in an Information-rich Economy This paper uses basic empirical facts from attention and perception psychology for a behavioral approach to equilibrium analysis at the industry and the macroeconomic level. The paper endogenously determines whether an economy is information-rich and whether scarcity of attention complements economic scarcity. A conventiona...

A novel lignosilicate (LS) composite was synthesized from pre-extracted (hot water, 80% ethanol, 0.3 N NaOH) lignin of rice husk (RH) using TEOS as matrix. The extracted lignins were subjected to surface modification by acetylation followed by in situ synthesis of lignosilicate (LS) composites by sol-gel method for application in nickel removal. LS were characterized by FT-IR, scanning electron...

We report the observation of terahertz emission from YBa2Cu3O72d thin films excited by 1.5-eV, 150-fs pulses in the absence of external electric or magnetic fields. This emission is characterized for optimally doped d50 films and underdoped d50.5 films, over a range of temperatures T, 4 K,T,300 K, where the films change from superconductors to correlated metals. It exhibits a pronounced 4f depe...

This paper analyses experimental data on sediment incipient motion with varying bed thickness (of d50, 5, 10 and 24 mm). Sediment particles (with sizes ranging from 0.5 mm to 4.78 mm) were used evaluate the effect of deposited bed. Variation shear velocity estimation was investigated where critical Shields parameter expressed using bed-slope product u∗cb, log-law u∗cl extended in terms mean vel...

By distinguishing between producible and nonproducible public goods, we are able to propose a general equilibrium model with externalities that distinguishes between and encompasses both the Starrett [1972] and Boyd and Conley [1997] type external effects. We show that while nonconvexities remain fundamental whenever the Starrett type external effects are present, these are not caused by the ty...

Endogenous growth theory has had some success in explaining the observed data related to the process of economic growth. However, the results of the models in this literature are typically very sensitive to their micro-economic structure. It is therefore important to understand how the growth process behaves under more general specifications of such features as the number of commodities, the nu...