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201.
Aquatic ecosystems are threatened by increasing variability in the hydrologic responses. In particular, the health of river ecosystems in steeply sloping watersheds is aggravated due to soil erosion and stream depletion during dry periods. This study suggested and assessed a method to improve the adaptation ability of a river system in a steep watershed. For this, this study calibrated soil and water assessment tool (SWAT) for runoff and sediment, and quantified the changes in hydrologic responses such as groundwater recharge rate soil erosion and baseflow according to two scenarios for adjustment of the watershed slope (steep to mild). Here, one scenario was set by three measured slopes, and the other was set by fixing the entire watershed slopes with 5 %. Moreover, SWAT and web-based hydrograph analysis tool (WHAT) models were applied to estimate groundwater recharge, soil erosion, and baseflow in the Haean-myeon watershed in South Korea. The results show that the reduction of watershed slope increased groundwater recharge and baseflow, and decreased sediment. Specifically, groundwater recharge rate was increased from 257.10 to 364.60 mm, baseflow was increased from 0.86 to 1.19 m3/s, and sediment was decreased from 194.6 to 58.1 kg/km2. Based on these results, the suggested method will positively contribute to aquatic ecosystems and farming environments in a steeply sloping watershed due to improvements in the quantity and quality of river water.  相似文献   
202.
A combined proteomic approach was applied for the separation, identification, and comparison of two major storage proteins, beta-conglycinin and glycinin, in wild (Glycine soja) and cultivated (Glycine max) soybean seeds. Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) with three different immobilized pH gradient (IPG) strips was an effective method to separate a large number of abundant and less-abundant storage proteins. Most of the subunits of beta-conglycinin were well-separated in the pH range 3.0-10.0, while acidic and basic glycinin polypeptides were well-separated in pH ranges 4.0-7.0 and 6.0-11.0, respectively. Although the overall distribution pattern of the protein spots was similar in both genotypes using pH 3.0-10.0, variations in number and intensity of protein spots were better resolved using a combination of pH 4.0-7.0 and pH 6.0-11.0. The total number of storage protein spots detected in wild and cultivated genotypes was approximately 44 and 34, respectively. This is the first study reporting the comparison of protein profiles of wild and cultivated genotypes of soybean seeds using proteomic tools.  相似文献   
203.
The bulky and rigid triphenylmethyl group was grafted onto polyurethane (PU) to reduce the molecular attractions between hard segments and to improve the mobility of the PU chain under freezing conditions. The triphenylmethyl-grafted PU exhibited improvement in the cross-link density, solution viscosity, maximum tensile stress, shape recovery at 10 °C, and low temperature flexibility compared with the plain PU. The soft segment melting was not affected by the grafted triphenylmethyl group, whereas the soft segment crystallization disappeared with the increase of the triphenylmethyl group content. The glass transition temperature (Tg) increased with the increase of the triphenylmethyl group content. The rapid increase of the tensile strength and shape recovery at 10 °C resulted from the cross-linking effect, whereas the strain at break and shape retention at -25 °C slightly decreased with the increase of the triphenylmethyl group content. The triphenylmethylgrafted PU displayed an excellent low temperature flexibility even at -50 °C due to the improved mobility of the PU chain compared to ordinary PU.  相似文献   
204.
An eight‐week feeding trial was conducted to evaluate the contribution of biofloc on dietary lipid requirement in whiteleg shrimp Litopenaeus vannamei. Five diets with graded levels of dietary lipid (45, 60, 90, 120 and 150 g/kg) were fed to juvenile shrimp. Final weight, weight gain and specific growth rate of shrimp fed diets with 60, 90 and 120 g/kg lipid levels were significantly higher than those of shrimp fed diets with lipid levels 45 and 150 g/kg (p < .05). Feed efficiency and protein efficiency ratio of shrimp fed 60, 90 and 120 g/kg were higher than those fed 150 g/kg diet. Plasma total cholesterol and triglyceride levels were lower in shrimp fed 45 g/kg compared with those fed the 90 g/kg (p < .05). Also, lysozyme activity for 90 g/kg group was higher than the 15 g/kg group. Hepatopancreas lipase and amylase activities of shrimp fed 90 and 120 g/kg diets were significantly higher than those of shrimp fed 45 and 150 g/kg diets. Broken‐line regression analysis for weight gain indicated that the dietary lipid requirement of whiteleg shrimp juveniles reared in a biofloc system was estimated to be higher than 56 g/kg but <60 g/kg.  相似文献   
205.
ABSTRACT

The present study was conducted to evaluate growth performance and color enhancement of goldfish, Carassius auratus, fed diets containing 0, 50, 100, 200, and 250 mg kg?1 diet of annatto dye (AD) for 60 days. The survival rate was significantly higher in fish fed 100, 200, and 250 mg AD kg?1 diet over than these fed control and 50 mg AD kg?1 diet (p < 0.05). AD significantly (p <0 .05) increased the pigmentation in the skin and caudal fin of goldfish in a concentration dependent manner (R2 = 0.995, 0.997). The highest amount of total carotenoid deposition in fish skin and fins were given by diets containing 200–250 mg AD kg?1 diet. The highest redness (a*) of 43.21 and yellowness (b*) of 12.53 were obtained by 250 and 50 mg AD kg?1, respectively. The present results show that AD can be successfully used as an alternative natural carotenoid source in goldfish diets at levels of 200–250 mg AD kg?1 diet.  相似文献   
206.
Sweet crab apple (Malus coronaria) is a popular ornamental tree planted in gardens and urban forests in South Korea. In 2018, severe symptoms were observed on street plantings of sweet crab apple in Jinju, South Korea including shoot blight: shoot tips, twigs and foliage of infected trees turned brown, and dried completely. The causal agent isolated from the disease lesions was identified as Pseudomonas viridiflava based on biochemical tests, pathogenicity, and 16S rRNA and rpoD gene sequencing. On artificial inoculation, this pathogen not only caused shoot blight on sweet crab apple, but also bulb rot and leaf blight on onion. Here, we report the occurrence of bacterial shoot blight caused by P. viridiflava in sweet crab apple for the first time in the world.  相似文献   
207.
Streptomyces sp. GET02.ST and Achromobacter sp. GET02.AC were isolated together from the gut of the wharf roach, Ligia exotica, inhabiting the intertidal zone of the west coast of Korea. The co-cultivation of these two strains significantly induced the production of two new metabolites, ligiamycins A (1) and B (2), which were barely detected in the single culture of Streptomyces sp. GET02.ST. The planar structures of ligiamycins A (1) and B (2) were elucidated as new decalins coupled with amino-maleimides by the analysis of various spectroscopic data, including nuclear magnetic resonance (NMR), ultraviolet (UV), and mass (MS) data. The assignment of two nitrogen atoms in amino-maleimide in 1 was accomplished based on 1H-15N heteroatom single quantum coherence spectroscopy (HSQC) NMR experiments. The relative configurations of the ligiamycins were determined using rotating frame Overhauser effect spectroscopy (ROESY) NMR data, and their absolute configurations were deduced by comparing their experimental and calculated optical rotations. Ligiamycin A (1) displayed antibacterial effects against Staphylococcus aureus and Salmonella enterica, while ligiamycin B (2) exhibited mild cell cytotoxicity against human colorectal cancer cells.  相似文献   
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