The toxicity of heavy metals, which is associated with the high affinity of the metals for thiolate rich proteins, constitutes a problem worldwide. However, despite this tremendous toxicity concern, the binding mode of As(III) and Pb(II) to proteins is poorly understood. To clarify the requirements for toxic metal binding to metalloregulatory sensor proteins such as As(III) in ArsR/ArsD and ...

High-temperature, controlled incineration and thermal treatment of contaminated soils, sediments, and wastes at Superfund sites are often preferred methods of remediation of contaminated sites under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 and related legislation. Although these methods may be executed safely, formation of toxic combustion or reaction by...

Cd2+ provokes an immediate production of inositol trisphosphate and the release of Ca2+ from internal stores in human fibroblasts and some other mammalian cells. Ni2+, Co2+, Fe2+, and Mn2+ evoke the release of stored Ca2+, but are less potent than Cd2+ (apparent K0.5 = 40 nM). Zn2+ and Cu2+ competitively inhibit Ca2+ release evoked by Cd2+ without affecting Ca2+ release by hormones such as brad...

Hyperaccumulators are being intensely investigated. They are not only interesting in scientific context due to their "strange" behavior in terms of dealing with high concentrations of metals, but also because of their use in phytoremediation and phytomining, for which understanding the mechanisms of hyperaccumulation is crucial. Hyperaccumulators naturally use metal accumulation as a defense ag...

We demonstrate that left-handed resonance transmission from metallic metamaterial, composed of periodically arranged double rings, can be extended to visible spectrum by introducing an active medium layer as the substrate. The severe ohmic loss inside metals at optical frequencies is compensated by stimulated emission of radiation in this active system. Due to the resonance amplification mechan...

Samples of active coke, fresh and spent after cleaning flue gases from communal waste incinerators, were investigated. The outer layers of both coke particles were separately removed by comminution in a spouted bed. The samples of both active cokes were analysed by means of densities, mercury porosimetry, and adsorption technique. Remaining cores were examined to determine the degree of consump...

The concentrations of hydroxyl groups located inside and on the surface oxide films of a commercially pure titanium, cp-Ti, a type 316L austenitic stainless steel, SS, and a cobalt-chromium-molybdenum alloy, Co-Cr-Mo, were evaluated using X-ray photoelectron spectroscopy, XPS, and a zinc-complex substitution technique. As a result, the concentrations of the hydroxyl groups detected by the zinc-...

Metals are essential for life, playing critical roles in all aspects of the central dogma of biology (e.g., the transcription and translation of nucleic acids and synthesis of proteins). Redox-inactive alkali, alkaline earth, and transition metals such as sodium, potassium, calcium, and zinc are widely recognized as dynamic signals, whereas redox-active transition metals such as copper and iron...

Even though gold is the noblest of metals, a weak chemisorber and is regarded as being quite inert, it demonstrates significant electrocatalytic activity in its nanostructured form. It is demonstrated here that nanostructured and even evaporated thin films of gold are covered with active sites which are responsible for such activity. The identification of these sites is demonstrated with conven...