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Sucrose is the most commonly transported sugar in plants and is easily assimilated by insects to fulfill the requirement of physiological metabolism. BmSuc1 is a novel animal β-fructofuranosidase (β-FFase, EC 3.2.1.26) - encoding gene that was firstly cloned and identified in silkworm, Bombyx mori . BmSUC1 was presumed to play an important role in the silkworm-mulberry enzymatic adaptation system by effectively hydrolyzing sucrose absorbed from mulberry leaves. However, this has not been proved with direct evidence thus far. In this study, we investigated sucrose hydrolysis activity in the larval midgut of B. mori by inhibition tests and found that sucrase activity mainly stemmed from β-FFase, not α-glucosidase. Next, we performed shRNA-mediated transgenic RNAi to analyze the growth characteristics of silkworm larvae and variations in glycometabolism in vivo in transgenic silkworms. The results showed that in the RNAi- BmSuc1 transgenic line, larval development was delayed, and their body size was markedly reduced. Finally, the activity of several disaccharidases alone in the midgut and the sugar distribution, total sugar and glycogen in the midgut, hemolymph and fat body were then determined and compared. Our results demonstrated that silencing BmSuc1 significantly reduced glucose and apparently activated maltase and trehalase in the midgut. Together with a clear decrease in both glycogen and trehalose in the fat body, we conclude that BmSUC1 acts as an essential sucrase by directly modulating the degree of sucrose hydrolysis in the silkworm larval midgut, and insufficient sugar storage in the fat body may be responsible for larval malnutrition and abnormal petite phenotypes. [ABSTRACT FROM AUTHOR]

Abstract: The research on volatility spillover effects between many stock markets is an important subject of finance in recent years. This paper investigates the volatility spillover between the stock markets in Shanghai and Hong Kong. Granger causality model and GARCH (1, 1)-in-mean model are adopted to test and analyze the relevance of the return and volatility between the two markets. The empirical results suggest that Hong Kong equity market has one-way significant effects on Shanghai stock market after the reform of the shareholder structure of listed companies. [Copyright &y& Elsevier]

A novel amino-functionalized magnetic adsorbent (Fe 3 O 4 @C@DETA) was developed for adsorption of Cr(III) and Cr(III)-EDTA from wastewater. Fe 3 O 4 @C@DETA were successfully prepared by modification of Fe 3 O 4 @C with diethylenediamine (DETA), which exhibits a core-shell structure and sufficient saturation magnetization. Fe 3 O 4 @C@DETA exhibits much better adsorption performance for Cr(III) and its chelates than the Fe 3 O 4 @C because of newly introduced amino active sites. The enhanced adsorption capacity of Fe 3 O 4 @C@DETA for Cr(III) is 44.74 mg g−1 (at 25 °C and pH 3.0), which is due to the surface coordination with the newly introduced amino functional sites. The Cr(III)-EDTA anions as a whole was adsorbed through the electrostatic interaction with protonated amino species of the Fe 3 O 4 @C@DETA and have maximum adsorption capacity of 47.27 mg g−1 (at 25 °C and pH 3.0). The adsorption data of free and EDTA coordinated Cr(III) were followed the Langmuir equation, while the adsorption dynamics was well explained by pseudo second order model indicating the chemical nature of adsorption process. The higher concentration of Ca2+ ions in the wastewater compete for adsorption sites and inhibit the Cr(III) removal, while on other hand Ca2+ ions promotes the adsorption of Cr(III)-EDTA, because of electrostatic interaction with adsorbent active sits. Furthermore, the adsorbent can be easily separated by external magnetic field and regenerated in acidic solution. The adsorbent is stable, recyclable and have more than 75% regeneration efficiency and can be repeatedly used in the adsorption process. ga1 • DETA functionalized magnetic carbon-based adsorbent was developed. • Fe 3 O 4 @C@DETA exhibits higher adsorption capacity for Cr(III)-EDTA than Cr(III). • High salt reduced Cr(III) adsorption but improved Cr(III)-EDTA adsorption. • Ternary complex formation contributed to the enhanced Cr(III)-EDTA adsorption. • Fe 3 O 4 @C@DETA could be regenerated and the adsorbent can be reused. [ABSTRACT FROM AUTHOR]

• DTPA-Chitosan modified sewage sludge-based adsorbent was prepared • High adsorption capacity is due to surface complexation with amino and carboxyl functional sites. • Adsorption data followed BiLangmuir isotherm and pseudo second-order kinetic equation • Adsorbent is stable and can be reused after several cycles of regeneration The wastewater treatment process produces a huge amount of sewage sludge as a byproduct. A novel sewage sludge-based composite adsorbent (SS-CS@DTPA) was synthesized by simple one step surface functionalization with chelating properties of diethylenetriaminepentaacetic acid (DTPA) with crosslinking chitosan for the adsorption of Copper ions (Cu2+) from acidic aqueous solution. The surface functionalities were characterized by a scanning electron microscope, Brunauer-Emmett Teller, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy. The amino and carboxyl functional groups presence on the surface of the adsorbent was confirmed, which were mainly responsible for high adsorption capacity of Cu2+ ions and low surface area and pore volume. The adsorption capacity of SS-CS@DTPA was 31.42 mg/g at acidic condition (pH=3.0 at 25°C) and the adsorption data was well explained by BiLangmuir isotherm model suggesting the heterogenous surface of the adsorbent. The equilibrium point was reached in 60 min, and the adsorption kinetics were followed by the Pseudo second-order model. The adsorbent performance was excellent under the presence of a higher concentration of different monovalent (Na+, K+) and divalent (Ca2+, Mg2+) cations. The adsorption mechanism of Cu2+ ions on the surface of SS-CS@DTPA was assumed to be surface complexation with amino and carboxyl functional sites of the adsorbent. Furthermore, SS-CS@DTPA possesses more than half of adsorption capacity even after the 6th regeneration cycle, which makes it stable and recyclable adsorbent for Cu2+ ions adsorption. [ABSTRACT FROM AUTHOR]