A Comparison of Purchasing Power Parity between China and Japan

In this paper, the difference of income and consumption levels between Chinese and Japanese town dwellers＇ is compared, based on the purchasing power parity of each currency. The results using a historical series of the data and cross section data of the two countries are shown. And whenever the classification of Chinese and Japanese data is inconsistent, we reclassify Chinese material according to the Japanese classification.

Sorption of tylosin and sulfamethazine on solid humic acid

Tylosin（TYL） and sulfamethazine（SMT） are ionizable and polar antimicrobial compounds,which have seeped into the environment in substantial amounts via fertilizing land with manure or sewage. Sorption of TYL and SMT onto humic acid（HA） may affect their environmental fate. In this study, the sorption of TYL and SMT on HA at different conditions（pH, ionic strength） was investigated. All sorption isotherms fitted well to the Henry and Freundlich models and they were highly nonlinear with values of n between 0.5 and 0.8, which suggested that the HA had high heterogeneity. The sorption of TYL and SMT on HA decreased with increasing p H（2.0–7.5）, implying that the primary sorption mechanism could be due to cation exchange interactions between TYL~＋/SMT~＋ species and the functional groups of HA.Increasing ionic strength resulted in a considerable reduction in the K_d values of TYL and SMT,hinting that interactions between H bonds and π–π EDA might be an important factor in the sorption of TYL and SMT on HA. Results of Fourier transform infrared（FT-IR） and ~13C-nuclear magnetic resonance（NMR） analysis further demonstrated that carboxyl groups and O-alkyl structures in the HA could interact with TYL and SMT via ionic interactions and H bonds,respectively. Overall, this work gives new insights into the mechanisms of sorption of TYL and SMT on HA and hence aids us in assessing the environmental risk of TYL and SMT under diverse conditions.

Functional Characterization of a Type 4 Metallothionein Gene(CsMT4) in Cucumber

The excess amounts of heavy metals are toxic to various physiological processes in plants.Plant metallothioneins(MTs)are low molecular weight,cysteine-rich metal-binding proteins that play important roles in the detoxification of heavy metal ions.In this study,we characterized Cs MT4,a plant type 4 MT gene identified in a complementary DNA(cDNA)library prepared from young cucumber(Cucumis sativus)fruit.Cs MT4encodes a 90 amino acid protein with a predicted molecular mass of 9.028 kD.CsMT4 contains 17 cysteine residues in three highly conserved cysteine-rich domains.In contrast to the structures of other MTs,the highly conserved amino acid pattern CxCxxxCxCxxCxC is present in the middle of CsMT4.Furthermore,CsMT4 was markedly induced in various tissues by various concentrations of Cd^(2+)and Zn^(2+)(>1.0 mmol·L^(-1)).Similar to AtMT4b function,heterologous expression of Cs MT4 in E.coli could also improved its tolerance to Cd^(2+)and led to increased uptake of Cd^(2+),and the rate of Cd^(2+)uptake was the highest in cells expressing a phytochelatin-like peptide.Our findings demonstrate that CsMT4 might be obviously induced by the metal stress in cucumber,and improves tolerance to Cd ions but not Zn ions when heterologously expressed in E.coli,and suggest that the composition and arrangement of N-terminal Cys-residues in MT4 are associated with their binding capacity and preference for different metal ions.

An accurate selectivity estimation method for window queries and an implementation thereof

Spatial selectivity estimation is crucial to choose the cheapest execution plan for a given query in a query optimizer.This article proposes an accurate spatial selectivity estimation method based on the cumulative density(CD)histograms,which can deal with any arbitrary spatial query window.In this method,the selectivity can be estimated in original logic of the CD histogram,after the four corner values of a query window have been accurately interpolated on the continuous surface of the elevation histogram.For the interpolation of any corner points,we first identify the cells that can affect the value of point(x,y)in the CD histogram.These cells can be categorized into two classes:ones within the range from(0,0)to(x,y)and the other overlapping the range from(0,0)to(x,y).The values of the former class can be used directly,whereas we revise the values of any cells falling in the latter class by the number of vertices in the corresponding cell and the area ratio covered by the range from(0,0)to(x,y).This revision makes the estimation method more accurate.The CD histograms and estimation method have been implemented in INGRES.Experiment results show that the method can accurately estimate the selectivity of arbitrary query windows and can help the optimizer choose a cheaper query plan.