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71.
K. T. Win R. Nonaka A. T. Win Y. Sasada K. Toyota T. Motobayashi M. Hosomi 《Paddy and Water Environment》2012,10(4):281-289
Methane oxidation activity (MOA), methanotrophic bacteria (MOB), and CH4 emission in a paddy field fertilized with anaerobically digested slurry were compared between two varieties: a fodder rice variety Leaf star (LS) and a normal rice variety Kinuhikari (KN). Average MOA and MOB per unit dry root were significantly higher in KN (7.1?μmol?g?1 CH4?g?1 dry root h?1 and 3.7?×?107 MPN?g?1 dry root, respectively) than in LS (4.3?μmol?g?1 CH4?g?1 dry root h?1, 2.1?×?107 MPN?g?1 dry root), although MOA in the rice root per whole plant was not significantly different since root biomass of LS (1.5?g dry root plant?1) was significantly higher than that of KN (1.2?g dry root plant?1). MOA in the soil ranged from 0.031 to 0.087?μmol?g?1 CH4?g?1 dry soil h?1, but there were no significant differences in both depths (0–5 and 5–15?cm) between the two rice varieties. MOA in the rhizosphere soil was significantly different between the rice varieties at flowering, but not at tillering. Methane emission in the field was lower and MOA and MOB in the rice root were higher in LS than in KN at tillering, but the reverse results were found at flowering and maturity stages. Total CH4 emission during a growing period was not significantly different between LS (27.4?±?16.9?g CH4?m?2) and KN (24.0?±?19.5?g CH4?m?2). There was a significant negative relationship between CH4 emission and rice root MOB (P?<?0.01) or MOA (P?<?0.05) and significant positive relationship was observed between root MOA and MOB (P?<?0.01). This study revealed that choice of rice variety might be an important environmental issue in paddy cultivation since it can influence MOA and MOB in rice root and rhizosphere soil which relate with CH4 emission. 相似文献
72.
73.
Binod Prasad Luitel Na-Young Ro Ho-Cheol Ko Jung-Sook Sung Ju-Hee Rhee On-Sook Hur 《Journal of Crop Science and Biotechnology》2018,21(5):499-506
A total of 47 core collections of pepper (Capsicum chinense Jacq.) conserved in National Agrobiodiversity Center (NAC) were studied under field condition at Jeonju over two consecutive years (2015 and 2016). All accessions were characterized for their 14 qualitative and 16 quantitative characters. Results revealed that both qualitative and quantitative characters exhibited wide variation among the studied germplasm. Distribution of fruit characters (fruit length, width, and fruit wall thickness) among the accessions was positively skewed. Of the 47 accessions evaluated, 38.3% accessions had conical shaped fruits and mature fruit color was predominantly red (51.1%), orange (21.3%) and yellow (14.9%). Principal component analyses revealed that (i) 56.64% of the qualitative (fruit shape, color and fruit surface) variation and (ii) 89.42% of the quantitative (plant width, height and fruit maturity days) variation were explained by the first two components. Clustering revealed two groups and dendrogram revealed morphological variation among accessions. The phenotypic diversity exists in this core collections provide valuable information to improve agronomic traits in pepper breeding program. 相似文献
74.
In this study, the regenerated silk fibroin (SF)/nylon 6 blend filaments were fabricated by the wet spinning and miscibility,
structural characteristics, and thermal behavior of blend filaments were elucidated. The XRD results implied that the amount
of crystalline region of each polymer did not change linearly with the blend ratio suggesting that there are some changes
in the miscibility depending on the mixing ratio. The SEM observation revealed that the miscibility of blend decreased with
an increase of nylon 6 resulting in a severe phase separation in 50/50 SF/nylon 6 filament. The miscibility governed the thermal
behavior of blend filaments. The melting point of nylon 6 remained constant until 50 % nylon 6 content, whereas the melting
point depression appeared in 30 % nylon 6 implying miscibility. Interestingly, the thermal decomposition of the nylon 6 component
was accelerated by the presence of SF and the acceleration action of SF became stronger as the miscibility increased. 相似文献
75.
76.
Chih-Shen Chuang Kuang-Chung Tsai Yi-Chung Wang Ming-Kuang Wang Chun-Han Ko 《Journal of Wood Science》2010,56(3):208-215
Emulsion resins are widely used in wood-based materials for indoor furnishings. Previous studies have demonstrated that the
ability of a material to retard flame arises from the interactions between four major components: i.e., binder resin (BR);
carbonizing substrate (CS); foam-producing substance (FPS); and dehydrating agent (DA). Fire performance as influenced by
wetting and drying cycle (WDC) treatment has not yet been reported. This study aimed to compare the fire performance of materials
coated with EVAc (ethylene vinyl acetate copolymer) and PVAc (polyvinyl acetate copolymer) emulsion resins of differing BR/CS
ratios, subjected to investigation by cone calorimeter. Intumescent formulation significantly enhanced the fire retardancy
of painted plywood by exhibiting lower peak heat release rates (PHRR) and longer time to reach peak release rates. Additionally,
lower BR content in the fire retardant systems further enhanced flame retardancy. The fire retardancy decreases with increasing
the WDC treatment, caused by the weight loss of the coating materials. Infrared (FT-IR) analysis demonstrated that lower BR
content extends the survival duration of the phosphorcarbonaceous structure of chars. The findings in this study enhance the
state-of-the-art understanding of the effect of the intumescent. 相似文献
77.
The formation of a complex with aluminum by low molecular weight compounds and saponified ozone-treated kraft lignins was
evaluated based on the decrease in pH of their solutions on the addition of 0.1 M AlCl3. Decreases in pH were observed with the solutions containing compounds having adjacent carboxyl groups (oxalic acid), carboxyl/alcoholic
hydroxyl groups (glycolic acid), carboxyl/formyl groups (glyoxylic acid), and phenolic hydroxyl groups (protocatechuic acid)
on the addition of 0.1 M AlCl3. The malonic and phthalic acids, having two carboxyl groups, were also effective. These results show that the compounds were
effective in forming complexes with aluminum. This finding corresponds to the fact that aluminum toxicity is reduced by formation
of a complex with aluminum, except in phthalic acid. The chemical structures stated above in ozone-treated kraft lignins contribute,
at least partly, to the complex with aluminum. The pH of solutions containing saponified ozone-treated kraft lignins and alkaline-treated
kraft lignin decreased more than that without modified kraft lignins on the addition of 0.1 M AlCl3, showing that they were effective in forming a complex with aluminum. The high molecular weight part of saponified ozone-treated
kraft lignin was effective in forming a complex with aluminum and in reducing its toxicity. 相似文献
78.
Bock-Gie Jung Sun-Ju Cho Jae-Hyung Ko Bong-Joo Lee 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(3):213-220
Interleukin (IL)-10 exerts potent anti-inflammatory effects by suppression of both T-help (Th) 1 and Th2 cells. Previous studies have reported that IL-10 can ameliorate various inflammatory disorders. The present study was performed to examine whether IL-10 plasmid DNA could suppress development of atopic dermatitis (AD)-like skin lesions in NC/Nga mice, as an initial step towards the development of an appliance for use in dogs with AD. Intradermal injection of IL-10 plasmid DNA markedly inhibited the development of AD-like skin lesions, as evidenced by a marked decrease in skin symptoms and reduced inflammation within the skin lesions. Efficacy was confirmed by significant decreases in eosinophil ratio and serum IgE concentration, and a reduction in the number of Staphylococcus aureus recovered from the ear. Moreover, relative mRNA expression levels of IL-4 and interferon-γ in the skin lesions of mice injected with IL-10 plasmid DNA were also decreased compared with those of control mice. Of note, higher serum IL-10 levels in mice injected with IL-10 plasmid DNA were maintained compared with those in control mice. Taken together, the results indicate that IL-10 plasmid DNA can suppress the development of AD-like skin lesions by suppressing both Th1 and Th2 cell responses. Beneficial effects of IL-10 plasmid DNA may be expected in dogs with AD. 相似文献
79.
Philip Y. Lam Po Yee Chiu Hoi Yan Leung Na Chen Pou Kuan Leong Kam Ming Ko 《Fitoterapia》2010,81(8):1239-1245
The effect of schisandrin B (Sch B) on long-term ethanol-induced oxidative stress in various rat tissues was investigated. Long-term ethanol treatment increased reactive oxygen metabolites (ROM) level in plasma. The ethanol-induced oxidative stress was assessed by mitochondrial glutathione and α-tocopherol levels, antioxidant enzyme activities, malondialdehyde (mtMDA) production and heat shock protein (Hsp) 25/70 levels. Liver was most susceptible to oxidative stress with a significant increase in mtMDA production. Long-term Sch B treatment enhanced mitochondrial antioxidant status in a tissue non-specific manner. Sch B co-treatment ameliorated the alterations in plasma ROM levels, mtMDA production and Hsp 25/70 expression in rat tissues. 相似文献
80.
Han XQ Chung Lap Chan B Dong CX Yang YH Ko CH Gar-Lee Yue G Chen D Wong CK Bik-San Lau C Tu PF Shaw PC Fung KP Leung PC Hsiao WL Han QB 《Journal of agricultural and food chemistry》2012,60(17):4276-4281
A polysaccharide (GSP-6B) with a molecular mass of 1.86 × 10? Da was isolated from the fruiting bodies of Ganoderma sinense . Chemical composition analysis, methylation analysis, infrared spectroscopy, and nuclear magnetic resonance spectroscopy were conducted to elucidate its structure. GSP-6B contains a backbone of (1→6)-linked-β-D-glucopyranosyl residues, bearing branches at the O-3 position of every two sugar residues along the backbone. The side chains contain (1→4)-linked-β-D-glucopyranosyl residues, (1→3)-linked-β-D-glucopyranosyl residues, and nonreducing end β-D-glucopyranosyl residues. An in vitro immunomodulating activity assay revealed that GSP-6B could significantly induce the release of IL-1β and TNF-α in human peripheral blood mononuclear cell (PBMC) and showed no toxicity to either PBMC or a human macrophage cell line THP-1. GSP-6B could also activate dendritic cells (DC) by stimulating the secretion of IL-12 and IL-10 from DC. 相似文献