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141.
Curbing nutrient loads from rice cultivation has been an issue for the water quality management of surface water bodies in the Asian monsoon region. The objectives of this study were to develop paddy BMP scenarios and to evaluate their effectiveness on nutrient loads reduction using long-term model simulation. Totally five BMP scenarios were developed based on the three paddy farming factors of drainage outlet height, fertilizer type, and application amount and were compared with conventional practices. CREAMS-PADDY model was chosen for the paddy nutrient simulation, and two-year field experimental data were used for the model calibration and validation. The validated model was used to evaluate the developed BMP scenarios for the 46 years of simulation period. The observed nutrient loads were 15.2 and 1.45 kg/ha for nitrogen and phosphorus, respectively, and mainly occurred by early season drainage and rainfall runoff in summer. The long-term simulation showed that the soil test-based fertilization and drainage outlet raising practice were the two most effective methods in nutrient loads reduction. The combination of these two resulted in the greatest loads reduction by 29 and 37 % for T-N and T-P, respectively (p value < 0.001). Overall the effectiveness of the BMP scenarios was decreased in the wet season. As the conclusion, outlet height control and soil nutrient-based fertilization were suggested as the effective practices in paddy loads reduction and their combination can be a practicable BMP scenario for the paddy nutrient management.  相似文献   
142.
A series of benzenesulfonylurea derivatives possessing a branched hydroxymethyl moiety as an ortho-substituent were synthesized and found to have interesting herbicidal activity under submerged paddy conditions.  相似文献   
143.
Melanin synthesis is a defense mechanism that prevents skin damage, but excessive accumulation of melanin occurs in the skin in various reactions such as pigmentation, lentigines, and freckles. Although anti-melanogenic effects have been demonstrated for various naturally occurring marine products that inhibit and control tyrosinase activity, most studies have not been extended to in vivo applications. Phlorofucofuroeckol-A (PFF-A, 12.5–100 µM) isolated from Ecklonia cava has previously been shown to have tyrosinase-mitigative effects in B16F10 cells, but it has not been evaluated in an in vivo model, and its underlying mechanism for anti-melanogenic effects has not been studied. In the present study, we evaluated the safety and efficacy of PFF-A for anti-melanogenic effects in an in vivo model. We selected low doses of PFF-A (1.5–15 nM) and investigated their mitigative effects on pigmentation stimulated by α-MSH in vivo and their related-mechanism in an in vitro model. The findings suggest that low-dose PFF-A derived from E. cava suppresses pigmentation in vivo and melanogenesis in vitro. Therefore, this study presents the possibility that PFF-A could be utilized as a new anti-melanogenic agent in the cosmeceutical industries.  相似文献   
144.
Persistent organic pollutants (POPs) immobilization in farm land is an important issue to solve the residue in crop, and char has been considered for the remediation. In here, three commercially available chars like powdered oak char (POC), granulated oak char (GOC), and rice husk char (RHC) including powdered activated carbon (PAC) were investigated for their potential to adsorb and immobilize endosulfan in the soil. The maximum adsorption capacities (mg g?1) of the applied chars as POC, GOC, and RHC were 714.8, 322.6, and 181.8, respectively, and the capacity of POC was similar with PAC (713.8). In addition, the pore volume (0.138 cm3 g?1) and the surface area (270.3 m2 g?1) of POC were over 3-fold higher than GOC and RHC. The bioconcentration factor (BCF) reducing effect of α-, β-endosulfan, and endosulfan sulfate in oriental radish (Raphanus sativus var. sativus) was investigated by amendment of three commercially available chars to the contaminated soils. The BCF of total endosulfan was 0.025 in the radish root. POC treatments effectively suppressed the endosulfan uptake (BCF 0.002). However, GOC and RHC showed little BCF reducing effect of endosulfan in radish.  相似文献   
145.
Aquacultured fish are the richest natural source of protein. However, their overproduced biomass is often discarded due to production imbalance, causing considerable losses to the fishery industry. Therefore, it is necessary to utilize surplus fish and add value to overproduced fish. We performed complex enzyme-assisted hydrolysis to determine the correlation between its physical characteristics and anti-hypertensive activity in vitro and in vivo using an SHR model. Protamex-Pepsin assisted hydrolysate from Paralichthys olivaceus (POppH) produced by complex enzyme-assisted hydrolysis contained low-molecular-weight peptides and amino acids with anti-hypertensive activity. POppH regulated blood pressure and serum angiotensin II and angiotensin-I-converting enzyme levels, and histological and ultrasound image analysis revealed substantially reduced thickness and diameter of the carotid aorta in the POppH-administered SHR group. Therefore, we propose to reduce food loss due to overproduction by utilizing the anti-hypertensive activity and physical properties of POppH; the results demonstrate its application as a therapeutic agent.  相似文献   
146.

Purpose

This study predicts the optimal landfarming period for the total petroleum hydrocarbons (TPHs)-contaminated field soils that are subject to the combined landfarming and Fenton oxidation treatment.

Materials and methods

The TPHs degradation in the artificially contaminated model soils and the field-aged contaminated soils were compared in a laboratory scale. The soils were bioaugmented with the 16 petroleum hydrocarbon-degrading microbial cultures that are commercially available in Korea.

Results and discussion

The TPHs degradation by bioaugmentation in the model soils was 81?±?2% after 56 days, while it was only 27?±?2% after 74 days in the field-aged soils. The lower degradation in the field-aged soils can be attributed to the removal of a large part of the biodegradable and volatile TPHs fractions during the weathering process. The two-compartment model that can depict a fast-degradation phase followed by a slow-degradation phase predicted that the remedial goal of 475 mg kg?1 of TPHs could be achieved in the model soils within the conventional landfarming period of 60–120 days in Korea; however, the predicted period for the field-aged soils (710–4,086 days) was not practical requiring a combined biological and chemical treatment approach. Based on the kinetics study, the optimal landfarming period for the field-aged soils was 3 weeks and pre-Fenton oxidation can be used to meet the remedial goal.

Conclusions

The two-compartment model can be useful for predicting landfarming period for the combined landfarming and Fenton oxidation treatment of field-aged TPHs contaminated soils. The prediction of the optimal landfarming period could lead to the reduction in both the treatment cost and period.  相似文献   
147.
To study the interaction of phenylheterocycles with gamma-aminobutyric acid (GABA) receptors, 4- or 5-alkyl(or phenyl)-1-phenyl-1H-1,2,3-triazoles were synthesized and examined for their ability to inhibit the specific binding of [3H]-4'-ethynyl-4-n-propylbicycloorthobenzoate (EBOB), a noncompetitive antagonist, to the housefly and rat GABA receptors, as well as to the beta3 subunit homo-oligomer of the human GABA receptor investigated as a model receptor. 4-Substituted 1-phenyl-1H-1,2,3-triazoles were found to be more potent competitive inhibitors than the 5-substituted regioisomers in the case of all receptors. The 4-tert-butyl or 4-n-propyl analogue of 1-(2,6-dichloro-4-trifluoromethylphenyl)-1H-1,2,3-triazole exhibited the highest level of inhibition of [3H]EBOB binding to all receptors. Most of the synthesized analogues were more active in terms of the inhibition of EBOB binding to the housefly and human beta3 GABA receptors than to the rat receptor. The 4-cyclohexyl analogue showed the highest (185-fold) housefly versus rat receptor selectivity. A three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis demonstrated that both the 4-trifluoromethyl-2,6-dichloro substitution on the phenyl ring and a small, bulky, hydrophobic substituent at the 4-position of the triazole ring played significant roles in conferring high potency in cases involving the housefly and human beta3 receptors. The human beta3 receptor resembled the housefly receptor in terms of their recognition of phenyltriazoles, whereas 3D-QSAR analysis revealed a slight difference between the two receptors in terms of their mechanisms of recognition of the para-substituent on the phenyl moiety. Some of the triazoles synthesized here exhibited insecticidal activity, which was correlated with their ability to inhibit [3H]EBOB binding to the housefly receptor. Thus, 1-phenyl-1H-1,2,3-triazoles with the appropriate substituents exert insecticidal activity by selectively acting at the site for noncompetitive antagonism of insect GABA receptors.  相似文献   
148.
Commercial cytochrome c (Cyt c) was irradiated with Co-60 gamma-rays in the dose range of up to 3.0 kGy to investigate the enhancement of the nitrite reducing activity of Cyt c. The optimum irradiation dose to induce nitrite reducing activity for 30 muM Cyt c solution was 1.0 kGy under an O(2) atmosphere. The nitrite reducing activity of Cyt c irradiated at this dose was approximately 45-fold that of unirradiated Cyt c and ca. 1.2-fold that of nitrite reductase. The irradiation treatment resulted in unfolding of the peptide chain, exposure of the heme group, oxidation of methionine to methionine sulfoxide, dissociation of the sixth ligand (Met), and occurrence of autoxidation in Cyt c. Sepharose-immobilized irradiated Cyt c had a similar activity to that in solution. The resin retained the activity after five uses even after 1 year of storage. The irradiated Cyt c will be able to be used as a substitute for nitrite reductase.  相似文献   
149.
J. Lee    J. B. Yoon    J.-H. Han    W. P. Lee    J. W. Do    H. Ryu    S. H. Kim    H. G. Park 《Plant Breeding》2010,129(1):35-38
As one of the genic male sterility (GMS) materials in chili pepper ( Capsicum annuum L.), GMS1 has been used for commercial F1 hybrid seed production. The male sterility of GMS1 is controlled by a recessive nuclear gene, named ms 1 . In this study, we developed DNA markers linked to the ms 1 locus using a combination of bulked segregant analysis and amplified fragment length polymorphism (AFLP) in a segregating sibling population. From the screening of 1024 AFLP primer combinations, the AFLP marker E-AGC/M-GTG (514 bp) was identified as being linked to the ms 1 locus at a distance of about 3 cM. Based on internal sequencing analysis of the E-AGC/M-GTG marker between male fertile and sterile plants, we identified three small deletions with a size of altogether 42 bp in the male-fertile plant and developed a codominant sequence characterized amplified region (SCAR) marker. This SCAR marker may be valuable for marker-assisted breeding in the hybrid seed production system of chili pepper using the GMS1 line.  相似文献   
150.
The purpose of this study was to examine the effects of the structural properties of plain knit fabrics on the subjective perception of textures, sensibilities, and preference among consumers. This study, then, aimed to provide useful information with respect to planning and designing knitted fabrics by predicting the subjective characteristics analyzed according to their structural properties. For this purpose, we employed statistical analysis tools, such as factor and regression analysis and an adaptive-network-based fuzzy inference system(ANFIS), thereby combining the merits of fuzzy and neural networks and presupposing a non-linear relationship. Through factor analysis, we also categorized the subjective textures into ‘roughness’, ‘softness’, ‘bulkiness’ and ‘stretch-ability’ with R2=70.32 %: and categorized the sensibilities into ‘Stable/Neat’, ‘Natural/Comfortable’ and ‘Feminine/Elegant’ with R2=68.12 %. We analyzed subjective textures, sensibilities, and preference with ANFIS, assuming non-linear relationships; consequently, we were able to generate three or four fuzzy rules using wool/rayon fiber content and loop length as input data. The textures of roughness and softness exhibited a linear relationship, but other subjective characteristics demonstrated a non-linear input-output relationship. Compared with linear regression analysis, the ANFIS exhibited had higher predictive power with respect to predicting subjective characteristics.  相似文献   
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