Many geological formations consist of crystalline rock that have very low matrix permeability but allow flow through an interconnected network of fractures. Understanding the flow of groundwater through such rocks is important in considering disposal of radioactive waste in underground repositories. A specific area of interest is the conditioning of fracture transmissivities on measured values ...

The grass shrimp (Palaemonetes vuigaris) orients itself by means of the polarization pattern of the sky visible through Snell's window of the water surface. The celestial polarization pattern viewed from water is distortt.~! and modified because of refraction and repolarization of skylight at the air-water interface. This work provides a quantitative account of the repolarization of skylight tr...

background: chronic administration of morphine cause physical dependence but the exact mechanism of this phenomenon remains unclear. the aim of this study is the assessment of systemic and intracerebroventricular (icv) administration of ramelteon (a melatonin receptor agonist) on morphine physical dependence. methods: 88 adult male rats were divided into 2 major groups, namely “systematic” and ...

background: stimulants addition and abuse can cause some functional and morphological changes in the normal function of glands and hormones. methamphetamine as an addictive stimulant drug affects the hypothalamic-pituitary-adrenal (hpa) axis and consequently makes some changes in the psychological state of the drug users. the present study aims to examine the relationship between plasma levels ...

Introduction: The brain glutamate neurotransmitter system and its NMDA receptors in the nucleus accumbens play an important role in the incidence of the phenomena of sensitivity and addiction. The present study examined the inhibitory effect of glutamate NMDA receptors in the nucleus accumbens in response to chronic stress. Methods: After the unilateral and bilateral cannula placement in the ...

Two ultrafast laser pulses at the fundamental Ti:sapphire laser wavelength of 800 nm and the second harmonic at 400 nm were used to study the temporal evolution of the transmissivity in fused silica and resulting material ablation. It was observed that there was a sharp drop in the transmissivity of the probe pulse at zero delay between the two pulses, indicating that there was enhanced absorpt...

Memory is facilitated when the retrieval context resembles the learning context. The brain structures underlying contextual influences on memory are susceptible to stress. Whether stress interferes with context-dependent memory is still unknown. We exposed healthy adults to stress or a control procedure before they learned an object-location task in a room scented with vanilla. Memory was teste...

Nanocrystalline silicon and silicon-germanium alloys are promising thermoelectric materials that have achieved substantially improved figure of merits compared to their bulk counterparts. This enhancement is typically attributed to a reduction in lattice thermal conductivity by phonon scattering at grain boundaries. However, further improvements are difficult to achieve because grain boundary s...

This study investigates the feasibility of management of aquifer recharge (MAR) in Lebanon by designing well barriers to remove seawater intrusion from the fractured carbonate aquifers. Groundwater flow and saltwater/freshwater 50% sharp interface have been modeled along the coastal area using the Ghyben-Herzberg theory. The groundwater flow simulations have been supported by field transmissivi...