Nramp1 is a transporter that pumps divalent cations from the vacuoles of phagocytic cells and is associated with the innate resistance of mice to diverse intracellular pathogens. We demonstrate that sitA and mntH, genes encoding high-affinity metal ion uptake systems in Salmonella enterica serovar Typhimurium, are upregulated when Salmonella is internalized by Nramp1-expressing macrophages and ...

This work describes an implementation of optical phenomena on water surfaces. Despite high performance of current graphics hardware, shaders need essential simpli cations and numerical approximation. Here we propose the implementation of common effects such as re ection, refraction and caustics. In order to have a simple and elegant implementation we have done coarse approximations to achieve r...

The electron impact-induced fragmentation of 2,2-dimethyland 2-ethyI-l,findandione, 1 and 2, and their isomers, 3-isopropylideneand 3-propylidenephthalide, 3 and 4, respectively, was studied in detail by mass-analysed ion kinetic energy (MIKE) and collision-induced dissociation (CID-MIKE) spectrometry, including 'H and I3Clabelled analogues of 1 and 2. In all regimes of internal energy, the mol...

Divalent cations play an important role in the functions of biomembranes. This review deals with three topics: (1) Mg(2+)-mediated change in physical state of phospholipid induces conformation and activity change of reconstituted mitochondrial H(+)-ATPase, (2) a proper transmembrane Ca2+ gradient is essential for the higher enzymatic activity of adenylate cyclase, and (3) role of transmembrane ...

Extracting high-purity DNA directly from soil has become essential for the study of microorganisms in environmental samples. However, many soils contain compounds that inhibit enzymes involved in manipulating DNA. In this study, chemical flocculation using multivalent cations was investigated as a potential method for eliminating soil-based inhibitors during the extraction process. The addition...

The paper presents two heuristics for hardwarelsoftware partitioning of system level spec@cations. The main objective is to achieve pedormance optimization with a limited hardware and software cost. We consider minimization of communication cost and improvement of the overall parallelism as essential criteria. One ofthe heuristics is based on simulated annealing and the other on tabu search. Ex...

background: silica aerogel is the nano-porous form silica which is the lightest synthetic solid material. some specific properties of this material include high surface area (1500 m2.g-1), low density (< 0.03 g.cm-3) and high porosity (%99). in this research, silica aerogel was investigated as an adsorbent of the heavy metal cations in aqueous solutions. methods: the silica aerogel was synthesi...

Inhibition by polyvalent cations is a defining characteristic of voltage-gated proton channels. The mechanism of this inhibition was studied in rat alveolar epithelial cells using tight-seal voltage clamp techniques. Metal concentrations were corrected for measured binding to buffers. Externally applied ZnCl 2 reduced the H 1 current, shifted the voltage-activation curve toward positive potenti...

AB STRACT The effects of external Zn+2 and other divalent cations on K channels in squid giant axons were studied. At low concentration (2 mM) Zn+2 slows opening kinetics without affecting closing kinetics . Higher concentrations (5-40 mM) progressively slow opening and speed channel closing to a lesser degree. In terms of "shifts," opening kinetics are strongly shifted to the right on the volt...