Prevalence of the enteroaggregative Escherichia coli heat-stable enterotoxin 1 gene and its relationship with fimbrial and enterotoxin genes in E. coli isolated from diarrheic piglets.

A total of 720 Escherichia coli strains isolated from diarrheic piglets on 756 swine farms were screened for the presence of the enteroaggregative E. coli heat-stable enterotoxin 1 (EAST1) gene by polymerase chain reaction (PCR). Escherichia coli strains that carried EAST1 genes were also tested by PCR for the presence of 4 fimbriae (F4, F5, F6, F41), 2 heat-stable enterotoxins (STa and STb), and 1 heat-labile enterotoxin (LT) gene. One hundred sixty-four (22.7%) of the 720 E. coli isolates carried genes for EAST1. Of these 164 isolates, 62 (37.8%) carried EAST1 genes only, 11 (6.7%) carried genes for at least 1 of the fimbrial adhesins, 51 (31.1%) carried genes for at least 1 of the enterotoxins, and 40 (23.8%) carried genes for at least 1 of the fimbrial adhesins and enterotoxins. Forty-six percent of strains that carried EAST1 genes carried STa genes, and 16% of strains that carried EAST1 genes carried F4. The isolation rate of enterotoxigenic E. coli strains carrying genes for EAST1 gene was 63%. The 6 major genotypes observed in this study (in decreasing order) were EAST1+, EAST1+STa+, EAST1+STa+STb+, EAST1+STa+F5+, EAST1+STa+F4+, and EAST1+STb+F4+. EAST1 is widely prevalent among diarrheagenic strains of E. coli and may represent an important virulence determinant in the pathogenesis of enteric colibacillosis of preweaned pigs.     

Effects of soil moisture content on CO2 triggered soil physicochemical properties in a near-surface environment

Journal of Soils and Sediments - Carbon capture and storage (CCS) has been frequently discussed as a strategy for meeting CO2 emission reduction and its targets. However, some critical issues have...     

Preparation and properties of solid polymer electrolyte based on imidazolium-based ionic liquids for structural capacitors

We prepared solid polymer electrolytes (SPEs) composed of poly(ethylene glycol) monomethyl ether acrylate (1A9OMe) and 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIm][OTF]) and 1-ethyl-3-methylimidazolium bis(trifluoromethane sulfonyl) imide ([EMIm][TFSI]) as the ionic liquid. The SPEs formed by appropriately adding ionic liquids in the 1A9OMe prior to thermal cure. The ratio of 1A9OMe and ionic liquid was 1:9, 3:7, and 5:5, respectively. The characterization of solid polymer electrolytes were investigated using Fourier transform infrared spectroscopy in the attenuated total reflectance mode (FTIR-ATR), Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and glavanostatic charge-discharge test. The highest ionic conductivity of SPEs was found to be 4.90×10^?4 S/cm in a 1A9OMe/[EMIm][OTF] of 3:7. As IL contents were increased, the specific capacitance of supercapacitor was increased. The specific capacitance of supercapacitor for ionic liquid with large ion size was lower than that for ionic liquid with smaller ion size.     

Salt in irrigation water affects the nutritional and visual properties of romaine lettuce (Lactuca sativa L.)

The influence of salinity stress on the growth, appearance, and nutritional compounds, especially phenolic compounds and carotenoids, of romaine lettuce (Lactuca sativa L.), a low salt tolerant plant, was studied. The dry weight, height, and color of the lettuce plants were significantly changed by long-term irrigation (15 days) with higher NaCl concentration (i.e., >100 mM). However, no significant differences were observed in the growth and appearance among the control, all short-term treatments (2 days; 50, 100, 500, and 1000 mM), and long-term irrigation with low salt concentration. Moreover, in romaine lettuce treated with long-term irrigation with 5 mM NaCl, the total carotenoid content increased without color change, and the contents of major carotenoids in romaine lettuce, lutein and beta-carotene, increased 37 and 80%, respectively. No differences were observed in lutein and beta-carotene contents in short-term-treated lettuce. The phenolic content of the romaine lettuce declined with short-term salt irrigation, whereas there were no significant differences among treatments exposed to long-term irrigation. This research indicates that long-term irrigation with relatively low salt concentration, rather than short-term irrigation with high salt concentration, can increase carotenoid content in romaine lettuce without causing a tradeoff in yield or visual quality.     

韩国农业机械化政策和产后加工服务组织改革

[韩国农业经济转变和农业机械化发展]韩国农业的经济形势在过去的40年间发生了迅猛的变化。自1962年以来的六个连续的"五年经济发展计划"使韩国经济达到了发达国家在工业革命之后的150～200年才能达到的经济发展水平。经济     

Performance improvement of nonformaldehyde wrinkle resistant finished cotton fabrics treated with dialdehydes

Additives, such as sodium perborate and borax, were examined in dialdehyde wrinkle resistant finishing of cotton. Results indicated that the whiteness index (WI) of cotton treated with dialdehyde and additive showed about 90% of WI of the untreated cotton but with decrease in wrinkle recovery angle (WRA) due to inhibition effect of these additives. Effect of additive on the WRA reduction was more prominent with glutaraldehyde than with glyoxal. Reduction in WRA of cotton treated with both dialdehydes and boron compound was minimized by simultaneous addition of formic acid in the bath. Addition of formic acid was also generally beneficial in maintaining WI retentions after 8 months storage. Furthermore, boron compounds were also effective in improving retentions of mechanical properties. By FTIR analysis the residual aldehyde group was detected on the dialdehyde-finished cotton, whereas no peak was shown by addition of boron compounds. This suggested that the residual aldehyde group was a main cause of fabric yellowing on the dialdehyde-finished cotton. Dialdehyde with boron compound, therefore, can be used to replace a conventional formaldehyde-containing wrinkle resistant finishing of cotton.