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111.
Hyunwoo Kang Jongpil Moon Yongchul Shin Jichul Ryu Dong Hyuk Kum Chunhwa Jang Joongdae Choi Dong Soo Kong Kyoung Jae Lim 《Paddy and Water Environment》2016,14(4):499-508
To secure accuracy in the Soil and Water Assessment Tool (SWAT) simulation for various hydrology and water quality studies, calibration and validation should be performed. When calibrating and validating the SWAT model with measured data, the Nash–Sutcliffe efficiency (NSE) is widely used, and is also used as a goal function of auto-calibration in the current SWAT model (SWAT ver. 2009). However, the NSE value has been known to be influenced by high values within a given dataset, at the cost of the accuracy in estimated lower flow values. Furthermore, the NSE is unable to consider direct runoff and baseflow separately. In this study, the existing SWAT auto-calibration was modified with direct runoff separation and flow clustering calibration, and current and modified SWAT auto-calibration were applied to the Soyanggang-dam watershed in South Korea. As a result, the NSE values for total streamflow, high flow, and low flow groups in direct runoff, and baseflow estimated through modified SWAT auto-calibration were 0.84, 0.34, 0.09, and 0.90, respectively. The NSE values of current SWAT auto-calibration were 0.83, 0.47, ?0.14, and 0.90, respectively. As shown in this study, the modified SWAT auto-calibration shows better calibration results than current SWAT auto-calibration. With these capabilities, the SWAT-estimated flow matched the measured flow data well for the entire flow regime. The modified SWAT auto-calibration module developed in this study will provide a very efficient tool for the accurate simulation of hydrology, sediment transport, and water quality with no additional input datasets. 相似文献
112.
113.
Alterations in microbial culture conditions may trigger the production of diverse bioactive secondary metabolites. While applying various culture conditions and monitoring secondary metabolite profiles using LC/MS, hormaomycins B and C (1 and 2) were discovered from a marine mudflat-derived actinomycete, Streptomyces sp., collected in Mohang, Korea. The planar structures of the hormaomycins, which bear structurally-unique units, such as 4-(Z)-propenylproline, 3-(2-nitrocyclopropyl)alanine, 5-chloro-1-hydroxypyrrol-2-carboxylic acid and β-methylphenylalanine, were established as the first natural analogues belonging to the hormaomycin peptide class. The absolute configurations of 1 and 2 were deduced by comparing their CD spectra with that of hormaomycin. These hormaomycins exhibited significant inhibitory effects against various pathogenic Gram-positive and Gram-negative bacteria. 相似文献
114.
Hyunjun Woo Min-Kyung Kim Sohyeon Park Seung-Hee Han Hyeon-Cheol Shin Byeong-gon Kim Seung-Ha Oh Myung-Whan Suh Jun-Ho Lee Moo-Kyun Park 《Marine drugs》2021,19(8)
One of the well-known causes of hearing loss is noise. Approximately 31.1% of Americans between the ages of 20 and 69 years (61.1 million people) have high-frequency hearing loss associated with noise exposure. In addition, recurrent noise exposure can accelerate age-related hearing loss. Phlorofucofuroeckol A (PFF-A) and dieckol, polyphenols extracted from the brown alga Ecklonia cava, are potent antioxidant agents. In this study, we investigated the effect of PFF-A and dieckol on the consequences of noise exposure in mice. In 1,1-diphenyl-2-picrylhydrazyl assay, dieckol and PFF-A both showed significant radical-scavenging activity. The mice were exposed to 115 dB SPL of noise one single time for 2 h. Auditory brainstem response(ABR) threshold shifts 4 h after 4 kHz noise exposure in mice that received dieckol were significantly lower than those in the saline with noise group. The high-PFF-A group showed a lower threshold shift at click and 16 kHz 1 day after noise exposure than the control group. The high-PFF-A group also showed higher hair cell survival than in the control at 3 days after exposure in the apical turn. These results suggest that noise-induced hair cell damage in cochlear and the ABR threshold shift can be alleviated by dieckol and PFF-A in the mouse. Derivatives of these compounds may be applied to individuals who are inevitably exposed to noise, contributing to the prevention of noise-induced hearing loss with a low probability of adverse effects. 相似文献
115.
So Young Kim Myoung-Sook Shin Geum Jin Kim Hyukbean Kwon Myong Jin Lee Ah-Reum Han Joo-Won Nam Chan-Hun Jung Ki Sung Kang Hyukjae Choi 《Marine drugs》2021,19(8)
The epithelial–mesenchymal transition (EMT) of cancer cells is a crucial process in cancer cell metastasis. An Aquimarina sp. MC085 extract was found to inhibit A549 human lung cancer cell invasion, and caprolactin C (1), a new natural product, α-amino-ε-caprolactam linked to 3-methyl butanoic acid, was purified through bioactivity-guided isolation of the extract. Furthermore, its enantiomeric compound, ent-caprolactin C (2), was synthesized. Both 1 and 2 inhibited the invasion and γ-irradiation-induced migration of A549 cells. In transforming growth factor-β (TGF-β)-treated A549 cells, 2 inhibited the phosphorylation of Smad2/3 and suppressed the EMT cell marker proteins (N-cadherin, β-catenin, and vimentin), as well as the related messenger ribonucleic acid expression (N-cadherin, matrix metalloproteinase-9, Snail, and vimentin), while compound 1 did not suppress Smad2/3 phosphorylation and the expression of EMT cell markers. Therefore, compound 2 could be a potential candidate for antimetastatic agent development, because it suppresses TGF-β-induced EMT. 相似文献
116.
Takahisa YAMADA Seiki SASAKI Shin SUKEGAWA Takeshi MIYAKE Tatsuo FUJITA Hiroyuki KOSE Mitsuo MORITA Youichi TAKAHAGI Hiroshi MURAKAMI Fumiki MORIMATSU Yoshiyuki SASAKI 《Animal Science Journal》2009,80(4):486-489
Marbling, defined by the amount and distribution of intramuscular fat, is an economically important trait of beef cattle in Japan. The endothelial differentiation , sphingolipid G-protein-coupled receptor , 1 ( EDG1 ) gene has been considered as a positional functional candidate for the gene responsible for marbling. We have recently reported that 2 single nucleotide polymorphisms (SNPs), c.-312A > G in the 5' untranslated region (UTR) and c.*446G > A in the 3' UTR in EDG1 were associated with marbling in Japanese Black beef cattle, but this was not functional and a causal mutation for marbling. In the present study, we detected 2 novel SNPs, referred to as g.1475435G > A and g.1471620G > T , in the 5' flanking region of the EDG1 between low-marbled and high-marbled steer groups, which were previously shown to have EDG1 expression differences in musculus longissimus muscle. The g.1475435G > A SNP seemed not to segregate in Japanese Black beef cattle. The g.1471620G > T SNP was associated with the predicted breeding value for beef marbling standard number by the analyses using Japanese Black beef cattle population. Based on these findings, we hypothesized that the g.1471620G > T SNP might have an impact on EDG1 expression and also marbling. 相似文献
117.
We studied the effects of hyperhydricity on subcellular ultrastructure and physiology of leaves during in vitro regeneration of apple plants. Morphological, anatomical and ultrastructural differences between healthy leaf tissues obtained from greenhouse-grown plants and healthy and hyperhydric leaves obtained from shoots raised from nodal shoot explants in a bioreactor were investigated by electron microscopy and confocal laser scanning microscopy. Compared with healthy leaves, hyperhydric leaves showed abnormal, often discontinuous development of the epidermis and cuticle. Stomata were malformed. The leaf lamina appeared thickened and was characterized by poor differentiation between the palisade and spongy mesophyll tissue. Hyperhydric leaves had a significantly lower chloroplast number per cell and chloroplasts showed reduced thylakoid stacking compared with healthy leaves. Hyperhydricity resulted in a general decrease in concentrations of reduced and oxidized pyridine nucleotides, reflecting a reduction in metabolic activity. The activities of antioxidant enzymes, such as superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase were higher in hyperhydric leaves than in healthy leaves, indicating that hyperhydricity was associated with oxidative stress. Chlorophyll fluorescence measurements provided evidence of oxidative damage to the photosynthetic machinery in hyperhydric leaves: photochemical efficiency of photosystem II, effective quantum efficiency and photochemical quenching were all lower in hyperhydric leaves compared with healthy leaves. 相似文献
118.
A melt-process was used to prepare high molecular weight Poly(vinyl chloride) (PVC) films without the use of a conventional
plasticizer and heat stabilizer. Rigid PVC powder was swollen with dimethylformamide containing 4∼10 vol% water to reduce
its melting temperature. The swollen powder was pressed at a relatively low temperature of 75∼125 °C to form a film shape,
and then washed and dried. The visible light transmittance, X-ray diffraction, density and the tensile properties of the resulting
films were examined to estimate the success or failure of film formation. The films could be produced by not only the melt-process
but also a compression-process using the rigid, highly swollen PVC powder. The resulting films had no voids, which are generally
observed in PVC products formed by a solution process. The minimum temperature for these processes decreased with decreasing
water content in the mixture: The minimum temperatures according to the water content in the mixture to produce faultless
films through the melt-process were 4 %–105 °C, 6 %–115 °C, 8 and 10 %–125 °C, while those through the compression process
were 4 %–95 °C, 6 and 8 %–105 °C, 10 %–115 °C. 相似文献
119.
Tae Joung Ha Jin Hwan Lee Sang-Ouk Shin Seong-Hyu Shin Sang-Ik Han Hyun-Tae Kim Jong-Min Ko Myong-Hee Lee Keum-Yong Park 《Journal of Crop Science and Biotechnology》2009,12(2):79-86
This study assessed the altitudinal variations in the anthocyanin and isoflavone contents of six black seed coated soybean
[Glycine max (L.) Merrill] cultivars. The black soybean cultivars Heugcheong, Seonheuk, Geomjeong 1, Geomjeong 2, Cheongja 2, and Cheongja
3 were planted at Milyang (12 m above mean sea level — low altitude) and Muju (600 m — high altitude), Korea on 10 June 2005
and 2006. The total anthocyanin and isoflavone contents and individual components were investigated by reverse-phase high
performance liquid chromatography (HPLC). All black soybean cultivars cultivated in high altitude possessed significantly
higher total anthocyanin (p < 0.01) and isoflavone (p < 0.01) contents than those grown in low altitude. For anthocyanin composition, cyanidin-3-O-glucoside, cyanidin-3-O-galactoside, and peonidin-3-O-glucoside contents were significantly higher while delphinidin-3-O-glucoside contents was significantly lower at high altitude. The composition of individual isoflavones, 6″-O-malonyldaidzin, and 6″-O-malonylgenistin contents significantly increased at high altitude. 相似文献
120.
本文介绍了茶产业集群的概念和中国茶产业集群发展的特征。中国茶产业集群发展兼具阶段性;自发性形成和外生性形成机制并存;茶产业效应从第一产业向第二、第三产业快速辐射效应明显。笔者就进一步促进中国茶产业集群的发展,提出了需要进一步加强的支持体系。 相似文献