DE NOMBREUSES DONNÉES PROBANTES INDIQUENT que les programmes d’échange d’aiguilles sont rentables et peuvent aider à contrôler la transmission de l’infection par le VIH chez les consommateurs de drogues injectées. Ils peuvent toutefois être moins efficaces dans le cas des personnes qui s’injectent de la cocaïne, dont le nombre est à la hausse, et l’on craint que, en attirant les consommateurs d...

Membrane encapsulation is frequently used by the cell to sequester biomolecules and compartmentalize their function. Cells also concentrate molecules into phase-separated protein or protein/nucleic acid "membraneless organelles" that regulate a host of biochemical processes. Here, we use solution NMR spectroscopy to study phase-separated droplets formed from the intrinsically disordered N-termi...

The current work sought to develop predictive models between time-weighted average polycyclic aromatic hydrocarbon (PAH) concentrations in the freely dissolved phase and those present in resident aquatic organisms. We deployed semipermeable membrane passive sampling devices (SPMDs) and collected resident crayfish (Pacifastacus leniusculus) at nine locations within and outside of the Portland Ha...

The interfacial polymerization dynamics are tracked by successive droplet and capsule deformation using a straightforward microfl uidic approach. ab We use microfluidic polydimethylsiloxane (PDMS) devices to measure the kinetics of reactive encapsulations occurring at the interface of emulsion droplets. The formation of the polymeric shell is inferred from the droplet deformability measured in ...

in this work, nanostructured niti shape memory alloy with equal atomic percentage was produced through mechanical alloying. the result exhibited that after 60 h of mechanical alloying of high purity elemental powder mixtures of nickel and titanium by a planetary high-energy ball mill, the ti dissolved into ni lattice and niti (b2) phase with was obtained. the xrd investigations, sem observation...

Packed bed laboratory column experiments were performed to simulate the biogeochemical processes resulting from microbially catalyzed oxidation of organic matter. These included aerobic respiration, denitrification, and Mn(IV), Fe(III) and SO(4) reduction processes. The effects of these reactions on the aqueous- and solid-phase geochemistry of the aquifer material were closely examined. The dat...

Here we present a continuous molecule separation/concentration system using flowing microbubbles as carriers. Microbubbles continuously generated at the microchannel confluence are able to capture target substances dissolved in the liquid phase, and these bubble carriers are concentrated by continuously removing liquid phase from the stream to achieve the continuous molecule separation. In the ...

Solid-phase extraction (SPE) was tested for the isolation of dissolved lignin from diverse natural waters (fresh, estuarine, and marine) in preparation for CuO oxidation. Capillary GC coupled to selected-ion monitoring mass spectrometry (SIM-MS) of CuO oxidation products provides the high sensitivity and precision required for the identification and quantification of trace levels of lignin in s...

Predation at the microbial level can affect the fate of toxic trace metals. Metals associated with bacterial prey can be released into the dissolved phase following digestion by a predator, and/or metals can remain in the predator and be transferred potentially to the next level of the food chain. Toxic metal ions in the aqueous phase also are expected to modify the growth and predation rate of...

in this research performed during 1993-1994, the effluent of behran oil refmery, in south of tehran, which produces different types of industrial oil and greases, was studied and 3 methods of gravity separation, coagulation and flocculation and dissolved air flotation were investigated. in the first phase of the survey, the quality and quantity of the effluent were determined. this showed an av...