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In recent research works on coverless text information hiding, there are two main problems to be solved: low hiding success rate and small hiding capacity caused by the small amount of redundant information in the cover text. In order to overcome these problems, a method of coverless information hiding based on the combination of Chinese character components is proposed. This method is based on the traditional "location tag + keywords" mode for coverless information hiding, but with an improved design to extend the scope of available keywords for data hiding beyond the original cover texts. In our proposed method, each Chinese character in the keyword is split into two components: radicals and independent Chinese character, which are collected and will be recombined in pairs to generate the new Chinese characters. This method increases the hiding success rate and hiding capacity by generating Chinese characters that do not exist in the original cover text. The experimental result shows that the proposed method can utilize less size of carrier text database for efficient information hiding. When the size of carrier text database is reduced to 198 MB, the highest hidden capacity and hidden success that can be achieved are 13.45 and 0.99, respectively. [ABSTRACT FROM AUTHOR]

Using the daily rainfall from rain gauge stations in China and the daily data from the National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) reanalysis for each year of 1981-2008, a relationship between daily rainfall over the Yangtze-Huaihe River basin (YHB) and surface pressure over East Asia was statistically investigated and a summer weather index ( ISW) was defined from surface pressure for describing the daily variations of the atmospheric circulation and rainfall over the monsoon region of eastern China. The results show that the daily ISW is significantly correlated with the YHB rainy weather during summer. In higher- ISW days, there is usually more YHB rainfall. This link may be explained by the East Asian atmospheric circulation well. When ISW is higher, a low-pressure system frequently occurs over the land of southern China and an enhanced ridge appears over the South China Sea (SCS)-subtropical western Pacific region, which strengthens the seaward pressure gradient and southwesterly winds over southern China. Accordingly, the transport of water vapour toward the YHB and the ascending motion over the YHB strengthen remarkably. These variations in the daily atmospheric circulation finally lead to the frequent occurrence of the YHB rainy weather. Thus, ISW can represent the variations of the atmospheric circulation and rainy weather for most of the years of 1981-2008. For some extremely dry years over the YHB, however, ISW does not indicate the local large-scale rainfall well. This suggests an asymmetric descriptive ability of this index. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The excitatory amino acid transporter EAAC1 is an electrogenic Na+- and K+-gradient-driven transporter. In addition, the transporter mediates in the presence of Na+ and glutamate an anion conductance uncoupled from the transport of the glutamate. The first two N-terminal domains, important for forming the conductance mode, are extracellularly bordered by positively charged arginine residues, R39 and R61, being completely conserved throughout the transporter family. Also the conserved tyrosine residue Y98 could be important for Cl− conductance. We have investigated, by measurements of glutamate uptake and glutamate-induced currents, the effects of mutation of the arginines and the tyrosine to alanine. The mutation R39A hardly affects transport and channel mode. The mutation R61A, on the other hand, reduces the activity of transport but stimulates the channel conductance. In addition, the apparent Km values for glutamate uptake and for the glutamate-activated current are reduced. Glutamate stimulation of current seems to be associated with a voltage-dependent step, and the apparent valence of charge moved during binding is reduced in the R61A mutant. The mutation Y98A leads to reduced function with reduced apparent Km value for glutamate, and with strong reduction of the selectivity ration between NO3− and Cl− of the conductance mode. [Copyright &y& Elsevier]

A new caffeate compound, (E)-erythro-syringylglyceryl caffeate (1), was isolated from the roots and rhizomes of Nardostachys chinensis Batal., together with nine known phenolic compounds, including (+)-licarin A (2), naringenin 4', 7-dimethyl ether (3), pinoresinol-4-O-β-D-glucoside (4), caraphenol A (5), Z-miyabenol C (6), protocatechuic acid (7), caffeic acid (8), gallic acid (9) and vanillic acid (10). Their chemical structures were elucidated on the basis of spectroscopic data and physicochemical properties. Furthermore, this is the first report of compounds 2, 5 and 6 from Nardostachys genus.

The function of several membrane proteins is regulated by interaction with the SNARE protein syntaxin 1A; this includes regulation of GAT1, the transporter for the dominating inhibitory neurotransmitter gamma-aminobutyric acid (GABA). Here we demonstrate that also EAAC1, the transporter for the dominating excitatory neurotransmitter, is down-regulated by interaction with syntaxin 1A. This is shown by coexpression of EAAC1 and syntaxin 1A in Xenopus oocytes. Total EAAC1 expression is not significantly affected by the coexpression of syntaxin 1A, but more proteins become targeted to the membrane as demonstrated by biotinylation. Colocalization by coimmunoprecipitation suggests direct interaction between the two proteins. In contrast to the number of transporters, the glutamate transport activity becomes reduced, and even stronger inhibition is observed for the EAAC1-mediated conductance uncoupled from glutamate translocation. We conclude that the interaction of syntaxin 1A with EAAC1 particularly disrupts the structure of the conductance pathway of EAAC1., (Copyright (c) 2004 Wiley-Liss, Inc.)