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Membrane technologies have been widely applied in surface water treatment for drinking water purification. The main obstacles to the large scale application of membranes include membrane fouling, energy consumption and high investment. This study systematically investigated the performance of a hybrid system including in-situ coagulation and membrane module. The key parameters of a membrane system, including initial flux, operation mode (intermediate or continuous, time intervals, backwashing and aeration) was comprehensively investigated. In addition, the treatment performance in terms of turbidity, organic matter removal, membrane fouling and cleaning, and the effect of coagulants, were also studied. It was found that flat ceramic membranes with in-situ coagulation for surface water treatment performed much better without aeration and frequent backwashing, which gave interesting and important implications for future applications of a flat ceramic membrane, especially in drinking water purification. The hybrid system can achieve a high-water flux of 150 L/m2&middot, h (LMH) for 8 h operation without aeration and backwash. The removal of turbidity, UV254 and COD can achieve 99%, 85% and 81%, respectively. The cake layer on the membrane surface formed from the coagulation flocs turned out to prevent the membrane to be exposed to organic pollutant immediately which minimized the fouling problem. In addition, the fouling layer on the membrane surface can be easily cleaned by air scouring and backwash at the end of experiments, with a water flux recovery of higher than 90%. These results in this study provided an alternative strategy for membrane fouling control and energy conservation.

International Cooperation Project in Science & Technology of Fujian Province in China [2010I0012]; National Natural Science Foundation of China [51103122]; Natural Science Foundation of the Fujian Province for the Youth [2011J05137]

The development of multidrug resistance (MDR) is a crucial cause of therapy failure in gastric cancer, which results in disease recurrence and metastasis. Long non-coding RNAs (lncRNAs) have been proven to be critical in carcinogenesis and metastasis of gastric cancer. However, little is known about the roles of ANRIL (antisense non-coding RNA in the INK4 locus) in gastric cancer MDR. The aim of our study is to identify the biological function of ANRIL in gastric cancer MDR. In our results, ANRIL was highly expressed in gastric cancer tissues of cisplatin-resistant and 5-fluorouracil (5-FU)-resistant patients, and the same upregulation trends were observed in cisplatin-resistant cells (BGC823/DDP) and 5-FU-resistant cells (BGC823/5-FU). In addition, BGC823/DDP and BGC823/5-FU cells transfected with ANRIL siRNA and treated with cisplatin or 5-FU, respectively, exhibited significant lower survival rate, decreased invasion capability, and high percentage of apoptotic tumor cells. The influence of ANRIL knockdown on MDR was assessed by measuring IC50 of BGC823/DDP and BGC823/5-FU cells to cisplatin and 5-FU, the result showed that silencing ANRIL decreased the IC50 values in gastric cancer cells. Moreover, qRT-PCR and western blotting revealed that ANRIL knockdown decreased the expression of MDR1 and MRP1, both of which are MDR related genes; regression analysis showed that the expression of ANRIL positively correlated with the expression of MDR1 and MRP1, resprectively In summary, knockdown of lncRNA ANRIL in gastric cancer cells inhibits the development of MDR, suggesting an efficacious target for reversing MDR in gastric cancer therapy.

In order to investigate the photocatalytic degradation of phenol and methylene blue (MB) in aqueous solutions containing TiO 2 nanoparticles with different particle sizes and crystalline phases, an integrated membrane process combining microfiltration (MF) and ultrafiltration was introduced for the production and size separation of TiO 2 nanoparticles. TiO 2 nanoparticles obtained were characterized by XRD, TEM, SEM and BET techniques. The characterization results show that TiO 2 nanoparticles with various sizes and BET surface areas were obtained after MF fractionation. The size of TiO 2 nanoparticles from large to small follows the order: the retentate > the feed > the permeate while the sequence of BET surface area follows the order: the permeate > the feed > the retentate. Furthermore, a smaller disperse coefficient was achieved for both the permeate and the retentate in comparison with the feed. The studies on the photocatalytic oxidation of phenol and MB with TiO 2 nanoparticles before and after MF fractionation concluded that both the particle size and crystallite phase had strong influence on their photocatalytic performances.

Red sea bream, Chrysophrys major , were obtained from a marine fish cage-culture farm located in Hoshao Island near Xiamen, People's Republic of China, in August, (1990) Orthogonal array design was used to investigate the activating and inhibitory effects of the combination of waterborne Cu, Zn, Cr(VI) and Se(VI) on alkaline phosphatase (APase) activity in liver of C. major . The results obtained demonstrated that (1) the APase activity was significantly increased when Zn was at the level of 100 μg/1 whereas no change was found when Zn was at 500 μg/1; (2) Cu at 20 μg/1 increased APase activity whereas Cu at 100 μg/1 significantly inhibited APase activity; (3) the effect of Se(VI) on APase activity was minimal. However, Se(VI) could suppress the action of Cu on APase activity; and (4) Cr(VI) at concentrations of 0–500 μg/1 had little effect on APase activity. In addition, the results also showed that the duration of exposure was independent of the effects of the combination of waterborne metals on APase activity and no interactive effects of Zn × Se(VI) or Cu × Zn on APase activity were observed.

It is the purpose of the present work to provide information on the four-level orthogonal array design and data analysis for the optimization of analytical procedures. In the theoretical part, the construction and characteristics of the OA 16 (4 5 ) matrix is described in detail, followed by the data analysis strategy, in which the significance of the different factors is quantitatively evaluated by an analysis of variance (ANOVA) method including per cent contribution, and the difference among four levels for each factor is determined by Duncan's multiple F test. Furthermore, a third-order polynomial model representing response surface is established to estimate the effects for the factors with significant influences. In the application part, the proposed four-level orthogonal array design and data analysis method were applied to optimize polarographic reaction system for phosphorus determination. By conducting 16 preplanned experiments that span the maximum working range of the system, the best experimental conditions for achieving the largest response can be obtained. The expected value for each experimental trial calculated by the third-order regression equation established is in good agreement with the corresponding experimental value. To confirm the validity of the optimization procedure, additional experiments using the recommended conditions were performed. The results demonstrate that satisfactory results can be acquired. Therefore, the proposed four-level orthogonal array design as a chemometric approach to optimize the polarographic reaction system for phosphorus determination is rather efficient and effective.

Orthogonal array desings were applied to the optimization of liquid chromatographic analysis of pesticides used in golf courses. Three variables related to the composition of the mobile phase were studied: the percentage of acetonitrile, percentage of methanol, and the buffer pH. In the first experiment, each variable was tested at three levels using an OA9 (34) matrix, in which the interactions between the parameters were temporarily neglected. Based on the results of the first experiment, the second experiment was carried out following a two-level orthogonal array design with an OA8 (27) matrix, in which more exact levels for each variable were chosen, and the interaction effects were considered separately. Finally, the optimum conditions for liquid chromatographic analysis of the pesticides were proposed. The advantages and the disadvantages of three-level and two-level orthogonal array designs were discussed.

Four microwave digestion methods of fish tissue for selenium determination by hydride generation atomic absorption spectrometry were compared, in which potassium hexacyanoferrate(III) was chosen as a masking agent for eliminating matrix interferences. The results showed that the methods employing HNO(3)/H(2)O(2), HNO(3)/K(2)S(2)O(8)/H(2)O(2) and HNO(3)/H(3)PO(4)/H(2)O(2) digestion media were unreliable. However, the decomposition using the digestion media of HNO(3)/H(2)SO(4)/H(2)O(2) enabled adequate digestion of fish tissue and retention of selenium in a state amenable for determination. Therefore, the digestion procedures with HNO(3)/H(2)SO(4)/H(2)O(2) media are proposed for the determination of selenium in fish tissue by hydride generation atomic absorption spectrometry. The recoveries of the spiked samples investigated ranged from 90 to 102%. The result obtained from analyzing the NIES CRM No. 6 mussel was in good agreement with the reference value (reference value: 1.5 mug/g; found: 1.45 +/- 0.05 mug/g). The limit of detection for selenium was 0.03 mug/g dry mass for a 100 mg sample. The contents of selenium in local fish species investigated ranged from 0.49 to 2.90 mug/g, and the relative standard deviation for the determination of selenium was less than 8%.

1. 1. The effect of mercuric chloride on the substrate and ionic activation kinetics of Na+K+-ATPase activity in the kidney of fancy carp (Cyprinus carpio) was determined. 2. 2. Mercuric inhibition was shown to be a classical competitive nature with respect to substrate ATP activated Na+K+-ATPase, in that the apparent Km values were increased without a significant change in the apparent Vmax values. 3. 3. Mercuric inhibition was a mixed noncompetitive nature with respect to Na+-activated Na+K+-ATPase, where the apparent Km values were increased but the apparent Vmax values were decreased. 4. 4. Mercuric inhibition was a pure noncompetitive nature with respect to Mg2+ and K+-activated Na+K+-ATPase, in that the apparent Vmax values were decreased but not the apparent Km values. 5. 5. Based on the above results, we proposed a possible kinetic model for elucidating the biochemical mechanism of inhibition of mercuric chloride on Na+K+-ATPase in the kidney of fancy carp.

1. The Na+/K+-ATPase and Mg2+-ATPase activity of fancy carp (Cyprinus carpio) kidney homogenate without the presence of EDTA was significantly inhibited by mercuric chloride in a concentration-dependent manner. 2. The Na+/K+-ATPase and Mg2+-ATPase activity of fancy carp (Cyprinus carpio) kidney homogenate in the presence of EDTA showed no significant change with the increasing concentration of mercuric chloride. 3. The sensitivity of Na+/K+-ATPase to mercuric chloride was greater than that of the Mg2+-ATPase. 4. In conclusion, the use of EDTA in the determination of the effect of heavy metal on the ATPase activity as a toxicological index should be avoided. Using Na+/K +-ATPase activity as a toxicological index in the studies of heavy metal effect is better than using Mg2+-ATPase activity.

Three pepsinogens (PG1, PG2, PG3) were highly purified from the stomach of Japanese seabass (Lateolabrax japonicus) by ammonium sulfate fractionation, DEAE-Sephacel anion exchange column chromatography and Sephacryl S-200 gel-filtration. Two dimensional polyacrylamide gel electrophoresis (2D-PAGE) analysis revealed that the molecular masses of the three PGs were 35, 37, and 34 kDa, and their isoelectric points were 5.3, 5.1, and 4.7, respectively. Zymography analysis showed that the three pepsinogens had different mobilities and enzymatic activities under native conditions. Pepsinogens converted into their active form pepsins under pH 2.0 by one-step pathway or stepwise pathway. All three pepsins were completely inhibited by pepstatin A, a typical aspartic proteinase inhibitor. The N-terminal amino acid sequences of the three pepsinogens were determined to the 30th, 30th and 28th amino acid residue and those of their corresponding active form pepsins were also determined to the 19th, 18th and 20th amino acid residue, respectively. All amino acid sequences of Japanese seabass PGs revealed high identities to reported fish and mammalian pepsinogens. The effective digestion of fish and shrimp muscular proteins by pepsins indicated their physiological function in the degradation of food proteins.

In KIO(3)NH(3)NH(4)Cl medium, the selenium complex Se(O)SO(2-)(3), resulted from the reaction of selenite and sulphite in acid solution, gave a catalytic wave, which was applied to the determination of selenium in fish by differential pulse polarography. The sample was decomposed using the HNO(3)/H(2)SO(4)/H(2)O(2) digestion mixture in a closed PTFE digestion vessel with microwave heating. The detection limit was 0.06 mug/dm(3). The calibration curve was linear up to 8 mug/dm(3). Selenate present was reduced with hot hydrochloric acid to selenite. The recoveries of the selenite and selenate in two spiked samples investigated ranged from 91 to 104%. The NIES CRM No. 6 mussel was analyzed and the results obtained agreed well with the reference value (reference value: 1.5 mug/g; found: 1.43 +/- 0.05 mug/g). The results obtained by differential pulse polarography were in good agreement with those found by hydride generation atomic absorption spectrometry.

The theory and methodology of a five-level orthogonal array design for the optimization of analytical procedures were developed. In the theoretical section, the construction and characteristics of the OA25(56) matrix are described in detail while orthogonality is proved by means of a fourth-order polynomial model. Next, the assignment of experiments in the OA25(56) matrix is illustrated, followed by the data analysis strategy, in which significant/non-significant influence for each factor is quantitatively evaluated by the analysis of variance (ANOVA) technique including the percentage contribution, and the differences among five levels for each factor that has a significant influence are determined by Duncan's multiple F-test. Finally, the response surface methodology for the OA25(56) matrix is developed by using the equations obtained from the proof on orthogonality. In the application section, the reaction system for selenium determination by differential-pulse polarography, as a practical example, is employed to demonstrate the application of the OA25(56) matrix in the area of analytical chemistry.

The theory and methodology of a mixed-level orthogonal array design for the optimization of analytical procedures is described. Firstly, the method of construction of a mixed-level orthogonal array design is discussed in detail, followed by the assignment of experiments and the data analysis strategy in the design. The optimization of the parameters involved in the high-performance liquid chromatographic determination of polycyclic aromatic hydrocarbons is then employed to demonstrate the practical application of the proposed mixed-level orthogonal array design in the area of analytical chemistry.

The theory and methodology of a three-level orthogonal array design as a chemometric method for the optimization of analytical procedures were developed. In the theoretical section, firstly, the matrix of a three-level orthogonal array design is described and orthogonality is proved by a quadratic regression model. Next, the assignment of experiments in a three-level orthogonal array design and the use of the triangular table associated with the corresponding orthogonal array matrix are illustrated, followed by the data analysis strategy, in which significance of the different factor effects is quantitatively evaluated by the analysis of variance (ANOVA) technique and the percentage contribution method. Then, a quadratic regression equation representing the response surface is established to estimate each factor that has a significant influence. Finally, on the basis of the quadratic regression equation established, the derivative algorithm is used to find the optimum value for each variable considered. In the application section, microwave dissolution for the determination of selenium in biological samples by hydride generation atomic absorption spectrometry is employed, as a practical example, to demonstrate the application of the proposed three-level orthogonal array design in analytical chemistry.