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18When treating water with activated carbon, natural organic matter (NOM) is not only a target for 19 adsorptive removal but also an inhibitory substance that reduces the removal efficiency of trace 20 compounds, such as 2-methylisoborneol (MIB), through adsorption competition. Recently, superfine 21 (submicron-sized) activated carbon (SPAC) was developed by wet-milling commercially available 22 powdered activated carbon (PAC) to a smaller particle size. It was reported that SPAC has a larger 23 NOM adsorption capacity than PAC because NOM mainly adsorbs close to the external adsorbent 24 particle surface (shell adsorption mechanism). Thus, SPAC with its larger specific external surface 25 area can adsorb more NOM than PAC. The effect of higher NOM uptake on the adsorptive removal of 26 MIB has, however, not been investigated. Results of this study show that adsorption competition 27 between NOM and MIB did not increase when NOM uptake increased due to carbon size reduction;

Inorganic aluminum salts, such as aluminum sulfate, are coagulants that cause small particles, such as bacteria and viruses as well as inorganic particles, to destabilize and combine into larger aggregates. In this investigation, batch coagulation treatments of water samples spiked with Qbeta, MS2, T4, and P1 viruses were conducted with four different aluminum coagulants. The total infectious virus concentration in the suspension of floc particles that eventually formed by dosing with coagulant was measured after the floc particles were dissolved by raising the pH with an alkaline beef extract solution. The virus concentrations were extremely reduced after the water samples were dosed with aluminum coagulants. Viruses mixed with and adsorbed onto preformed aluminum hydroxide floc were, however, completely recovered after the floc dissolution. These results indicated that the aluminum coagulation process inactivates viruses. Virucidal activity was most prominent with the prehydrolyzed aluminum salt coagulant, polyaluminum chloride (PACl). Virucidal activity was lower in river water than in ultrapure water--natural organic matter in the river water depressed the virucidal activity. Mechanisms and kinetics of the virus inactivation were discussed. Our results suggest that intermediate polymers formed during hydrolysis of the aluminum coagulants sorbed strongly to viruses, either rendering them inactive or preventing infectivity.

Hybrid liposomes can be prepared by simply ultrasonicating a mixture of vesicular and micellar molecules in a buffer solution. The physical properties of these liposomes, such as size, membrane fluidity, phase transition temperature and hydrophobicity can be controlled by changing the composition. Hybrid liposomes composed of dimyristoylphosphatidylcholine and polyoxyethylene (10) dodecyl ether were found to inhibit the growth of human promyelocytic leukemia (HL-60) cells without using any drugs. Induction of apoptosis by hybrid liposomes in HL-60 cells was verified on the basis of fluorescence microscopy and flow cytometry analysis, after fusion and accumulation of hybrid liposomes, which was revealed on the basis of microphysiometer. We elucidated the pathways of apoptosis induced by the hybrid liposomes. That is, hybrid liposomes fused and accumulated in tumor cell membranes, and the apoptosis signal first passed through mitochondria, caspase-9 and caspase-3, second through Fas, caspase-8, caspase-3 and then reached the nucleus. Hybrid liposomes themselves can induce apoptosis in human tumor cells along with high inhibitory effects on the growth of tumor cells. ' 2005 Wiley-Liss, Inc.