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The confinement of water in organic self-assemblies with nanometer-sized pores is ubiquitous in nature. Water pools in sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles have been intensively studied as a representative model of such confined water. However, the freezing and melting behavior of such water pools is poorly understood owing to their poor structural stability under phase transition. In the present work, the melting of iced water pools accompanied by a reconstruction of AOT reverse micelles was studied with infrared spectroscopy. For all AOT reverse micelles tested ( R w : 1.2–4.4 nm), a characteristic ice–water coexistence phase was observed during melting. The results provide experimental evidence of the previously proposed core–shell structure of the water pool. For larger frozen reverse micelles ( R w > 2.3 nm), shifts of the υ (OH) bands were observed. The spectra of the shifted υ (OH) bands were similar to those for the melted water pools in the smaller micelles. The mechanism of the reconstruction of AOT reverse micelles from their frozen states and the corresponding transient changes in the local environments were also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Yeast biomass was methylated in a 0.1 M HCl methyl alcohol solution at room temperature and the methylated yeast (MeYE) was applied to the adsorptive separation of Cr(VI) and As(V) anions from aqueous solutions. At near-neutral pH, while Cr(VI) and As(V) anions were scarcely adsorbed onto unmethylated yeast biomass, the amounts adsorbed increased with increasing methylation degree. The amount of Cr(VI) adsorbed onto MeYE was almost constant at pH 4–6 and decreased with increasing pH above pH 6. The amount of As(V) adsorbed onto MeYE was rather lower than that of Cr(VI) and it had a peak at about pH 7. A metal-binding model was used to describe the adsorption characteristics of Cr(VI) and As(V) on MeYE. The results showed that MeYE has two different types of adsorption sites. The saturated amount of Cr(VI) and As(V) adsorbed onto MeYE having methylation degree 0.94 was 0.55 mmol g-1. [Copyright &y& Elsevier]

A new biodegradable flocculant was prepared from a common and inexpensive protein. Milk casein was methylated in a 0.05 M HCl methyl alcohol solution at room temperature. The methylated milk casein (MeCS), having a methylation degree of 81%, was applied to the separation or flocculation of diatomite in seawater (pH 8.1±0.1) at room temperature (18–23 °C). The flocculating ability of MeCS was evaluated by a sedimentation balance method (cumulative measurement method). The diatomite suspension was effectively flocculated by the addition of a small amount of MeCS (0.25 wt% of the diatomite weight). The results of sedimentation analysis showed that the size–frequency curve had a very sharp and high peak; thus the diatomite floc formed by MeCS had a rather uniform size. The settling velocity of diatomite floc at the appropriate MeCS dosages (0.25–2 wt% of diatomite) was about 3×10−3 m s−1. [Copyright &y& Elsevier]

A new biosorbent, methylated yeast (MeYE), was prepared for the adsorptive separation of proteins from aqueous solutions. Yeast was methylated in a 0.1 M HCl methyl alcohol solution at room temperature. About 80% of the carboxylic groups of yeast could be methylated within 9 h. The adsorption of egg albumin onto MeYE was studied to evaluate the protein adsorption ability of MeYE. At near neutral pH, egg albumin was scarcely adsorbed onto unmethylated yeast and the adsorbed amount of egg albumin increased with increasing methylation degree. The amount of egg albumin adsorbed onto MeYE increased with increasing pH from 4 to 7 and steeply decreased above pH 7. The Langmuir isotherm was applied to determine the apparent adsorption constant and the saturated adsorbed amount of egg albumin on MeYE. Both the apparent adsorption constant and the saturated adsorbed amount increased with the degree of methylation. The saturated adsorbed amount of egg albumin onto MeYE having methylation degree 77% was 8.41×10−6 mol g−1 or 0.378 g g−1 at near neutral pH. [Copyright &y& Elsevier]

We give an alternative definition of comprehensive Gro¨bner bases in terms of Gro¨bner bases in polynomial rings over commutative Von Neumann regular rings. Our comprehensive Gro¨bner bases are defined as Gro¨bner bases in polynomial rings over certain commutative Von Neumann regular rings, hence they have two important properties which do not hold in standard comprehensive Gro¨bner bases. One is that they have canonical forms in a natural way. Another one is that we can define monomial reductions which are compatible with any instantiation. Our comprehensive Gro¨bner bases are wider than Weispfenning’s original comprehensive Gro¨bner bases. That is there exists a polynomial ideal generated by our comprehensive Gro¨bner basis which cannot be generated by any of Weispfenning’s original comprehensive Gro¨bner bases. [Copyright &y& Elsevier]

A common and inexpensive protein, egg albumin, was applied to the solid–liquid separation or flocculation of diatomite. Egg albumin was methylated in a 0.05 M HCl methyl alcohol solution at room temperature. About 90% of the carboxylic groups of egg albumin could be methylated within 24 h. The adsorption of egg albumin onto diatomite at pH 6.8 was remarkably enhanced by methylation. The adsorption constant of methylated egg albumin to diatomite at 30 °C was about 100-fold larger than that of native egg albumin; however, the adsorption constant of methylated egg albumin decreased to about 1/100 with temperature decreasing from 30 to 6 °C. The saturated adsorption amount of egg albumin was also increased by the methylation. The flocculating ability of methylated egg albumin was examined with a diatomite suspension at 6 and 30 °C in the pH range from pH 2 to 11. The diatomite suspension was effectively flocculated by the addition of small amounts of methylated egg albumin (only 0.5–1 wt% against diatomite) over a wide pH range from pH 3 to 10. [Copyright &y& Elsevier]

A fundamental study about the selective foam separation of protein mixture was carried out. A solution containing two proteins, ovalbumin (OA) and lysozyme (LZ), and an anionic surfactant, sodium dodecyl sulfate (SDS), was adjusted to pH 6.0, which referred to an intermediate state between the isoelectric points of the proteins. The solution was processed by continuous foam separation. The results showed that a proper addition of SDS greatly improved the selective recovery of LZ to OA. The experimental data were well explained by a simple model that most of cationic protein molecules (LZ) are associated with SDS and the adsorption of all the species including LZ–SDS complexes are subjected to Langmuir adsorption isotherm. The results also showed that one of the Langmuir parameters, which means a kind of lyophillic property of adsorbed material, of LZ–SDS complexes was extremely large as compared with that of primary protein. [Copyright &y& Elsevier]

Adsorption of cadmium and lead ions to floc-type biosorbents was reported in this work. Two types of biosorbents containing a marine microalga, Heterosigma akashiwo (Hada) Hada, or a purple non-sulfur bacterium, Rhodobacter sphaeroides, were prepared. The micro-organisms inactivated by steam sterilization were immobilized in casein floc and cross-linked with glutaraldehyde. In the present immobilizing method, we obtained the biosorbents comprising as much as 67% of micro-organism on a dry-weight basis. Simple metal-binding models were applied to explain the adsorption mechanism of bivalent metal ions to the biosorbents. The results showed that casein acted as both the immobilizing material and the adsorbent material. The adsorption of bivalent metal ions to the biosorbents was due to bidentate binding to the acidic sites on casein and monodentate binding to the acidic sites on micro-organisms. The metal-binding constants and the binding capacities of micro-organisms were scarcely influenced by immobilization. [Copyright &y& Elsevier]

A kinetic study of cadmium and lead biosorption to a brown alga, Kjellmaniella crassiforia, was carried out. The shrinking core model derived by M. Gopala Rao and A. K. Gupta (Chem. Eng. J.24, 181, (1982)) was modified and adapted for description of the rate process of cadmium and lead biosorption to the alga. The biosorption rate process was well described and average apparent diffusion coefficient of about 9×10−6 cm2 s−1 was found for both cadmium and lead ions. The value was 20 to 50 times higher than the apparent diffusion coefficients of cadmium and lead ions in strong-acid resins like Dowex 50W-X8. [Copyright &y& Elsevier]

Abstract: In recent years, Boolean Gröbner bases have attracted the attention of many researchers, mainly in connection with cryptography. Several sophisticated methods have been developed for the computation of Boolean Gröbner bases. However, most of them only deal with Boolean polynomial rings over the simplest coefficient Boolean ring . Boolean Gröbner bases for arbitrary coefficient Boolean rings were first introduced by two of the authors almost two decades ago. While the work is not well-known among computer algebra researchers, recent active work on Boolean Gröbner bases inspired us to return to their development. In this paper, we introduce our work on Boolean Gröbner bases with arbitrary coefficient Boolean rings. [Copyright &y& Elsevier]

Abstract: The adsorption of ovalbumin (OA) onto the bubble surfaces was studied with various pHs (3.5, 4.6, 6.0 and 8.0) by a continuous foam separation technique. From the value of the saturated surface density of adsorbed OA, the variation of effective diameter (D) of an OA molecule on the bubble surface was estimated for various pHs (3.5, 4.6, 6.0 and 8.0) of the OA solutions, assuming that the cross section of the OA molecules be circular and that the OA molecules adsorb on the bubble surface in a closest packing structure. The estimated variation of D with pH was attempted to explain based on a model modified from that proposed by Pujar and Zydney [N.S. Pujar, A.L. Zydney, J. Chromatogr. A 796 (1998) 229–238]. The modified model could well reproduce the variation of the effective diameter with pH; the values of D calculated on the basis of the modified model almost agreed with that estimated from the saturated surface density in the present experimental pH range. From these, conclusion was drawn that the modified model presented in this study can express the variation in the effective diameter with pH. [Copyright &y& Elsevier]

The local and global transmission dynamics of influenza B virus is not completely understood mainly because of limited epidemiological and sequence data for influenza B virus. Here we report epidemiological and molecular characteristics of influenza B viruses from 2010 to 2013 in Leyte Island, Philippines. Phylogenetic analyses showed global dissemination of the virus among both neighboring and distant areas. The analyses also suggest that southeast Asia is not a distributor of influenza B virus and can introduce the virus from other areas. Furthermore, we found evidence on the local persistence of the virus over years in the Philippines. Taken together, both local persistence and global dissemination play a significant role in the circulation of influenza B virus. [ABSTRACT FROM AUTHOR]

Abstract: Continuous flow synthesis of gold nanoparticles was demonstrated using a microchannel reactor with glucose reduction in aqueous alkaline medium. Particle size, morphology, and visual/optical properties of the dispersion liquid were controlled dynamically by tuning of the rate of NaOH addition. Characteristic star-like nanoparticles formed spontaneously as a quasi-stable state, but they changed the morphology to round shape and showed spectral change over time. [Copyright &y& Elsevier]

Abstract: The 2009 human pandemic influenza (H1N1) virus possesses the HA gene of the H1 subtype. The evolutionary process of the 2009 H1N1 virus remains to be defined. We performed genetic analyses of the HA gene by comparing the 2009 H1N1 virus with seasonal human and swine viruses. We analyzed sequences of 116 2009 H1N1 viruses, and obtained 1457 seasonal H1N1, 365 swine H1, and 1332 2009 H1N1 viruses from the database. Selection pressure for the 2009 H1N1 virus was higher than that for the swine virus and equivalent to that for the seasonal virus. Positions 206 and 264 were found to be positively selected sites. We also identified sites under different selection pressures from the seasonal or swine virus that may be involved in imparting significant biological characteristics. The evolutionary characteristics of the H1 gene of the 2009 H1N1 virus differed from those of seasonal and swine viruses. [ABSTRACT FROM AUTHOR]