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101.
Pavani Dulanja Dissanayake Kumuduni Niroshika Palansooriya Mee Kyung Sang Dongyeop X. Oh Jeyoung Park Sung Yeon Hwang Avanthi Deshani Igalavithana Cheng Gu Yong Sik Ok 《Soil Use and Management》2022,38(3):1446-1458
Accumulation of microplastics (MPs) in agricultural environments has caused growing concern in recent years because of its detrimental impacts on soil quality, crop productivity and ecosystem function. This study was conducted to assess the impact of biochar on soil chemical and microbial properties in a MP-contaminated soil under two moisture regimes. Soil was contaminated with 1% (w/w) of low-density polyethylene MPs. Four types of standard biochar, that is, oil seed rape (OSR) biochar produced at 550°C (OSR 550) and 700°C (OSR 700) and soft wood pellet (SWP) biochar produced at 550°C (SWP 550) and 700°C (SWP 700), were applied at a rate of 5% (w/w). The control was maintained without MP addition. The samples were incubated in soil with two moisture regimes, that is, at 30% and 70% of the water holding capacity, and the soil chemical and microbiological properties were assessed after 100 days of incubation. OSR biochar application significantly increased soil pH (8.53–8.81) and electrical conductivity (0.51–0.58 dS/m) in both moisture regimes. The effect of biochar application on soil enzyme activity and microbial community composition did not show a clear trend. However, SWP 700 biochar improved soil enzyme activity compared with that of the control and improved bacterial diversity and evenness compared with those of other biochars, which was attributed to the high surface area available for microbial colonization. Low soil moisture content significantly reduced enzyme activity and bacterial richness even with biochar amendment, except for SWP 550 biochar. This study implies the suitability of biochar for improvement of soil quality in MP contaminated soil under both moisture regimes. However, further long-term studies are needed to get a clear understanding on the impact of different types of biochar on MP-contaminated soil. 相似文献
102.
Non-destructive and mathematical approaches of modeling can be very convenient and useful for plant growth estimation. To predict individual leaf area, fresh weight, and dry weight of a cucumber (Cucumis sativus L.), models were developed using leaf length, leaf width, SPAD value, and different combinations of these variables. Eight regression equations, commonly used for developing growth models, were compared for accuracy and adaptability. The three nonlinear models developed were as follows: individual leaf area (LA) = −210.61 + 13.358W + 0.5356LW (R2 = 0.980***), fresh weight (FW) = −2.72 + 0.0135LW + 0.00022LWS (R2 = 0.956***), and dry weight (DW) = 0.25 − 0.00102LS + 0.000077LWS (R2 = 0.956***), where L is the leaf length, W the leaf width, S the SPAD value, and LWS = L × W × S. For validation of the model, estimated values for individual leaf area, fresh weight, and dry weight showed strong agreement with the measured values, respectively. Leaf dry weight, especially, was estimated with a higher degree of accuracy through the use of a SPAD value, as well as leaf length and width. Therefore, it is concluded that models presented herein may be useful for the estimation of the individual leaf area, fresh weight, and dry weight of a cucumber with a high degree of accuracy. 相似文献
103.
Yun Kwon Seong-Hwan Kim Yoonho Shin Munhyung Bae Byung-Yong Kim Sang Kook Lee Ki-Bong Oh Jongheon Shin Dong-Chan Oh 《Marine drugs》2014,12(4):2326-2340
Three new secondary metabolites, amycofuran (1), amycocyclopiazonic acid (2), and amycolactam (3), were isolated from the sponge-associated rare actinomycete Amycolatopsis sp. Based on combined spectroscopic analyses, the structures of 1–3 were determined to be a new benzofuran glycoside and new indole alkaloids related to cyclopiazonic acids, a class that has previously only been reported in fungi. The absolute configurations of 1 and 3 were deduced by ECD calculations, whereas that of 2 was determined using the modified Mosher method. Amycolactam (3) displayed significant cytotoxicity against the gastric cancer cell line SNU638 and the colon cancer cell line HCT116. 相似文献
104.
Lyocell is drawing attention as a new material, environmentally friendly fiber. Precedent researches on lyocell are mostly
on structure, characteristics, physical properties, and dyeability. There are few researches on interlining for lyocell clothes
production. This study analyzes the correlation between the appearance-related performances of lyocell-interlining bonded
fabric and the mechanical properties of fusible interlining, lyocell face fabric, and lyocell-interlining bonded fabric. The
stiffness of lyocell-interlining bonded fabric correlates with LT, WT, G, 2HG, 2HG5, B, 2HB, WC, and RC of fusible interlining;
LT, EMT, G, 2HG, 2HB, RC, and T of lyocell face fabric; LT, WT, G, 2HG, 2HG5, B, 2HB, and T of lyocell-interlining bonded
fabric. The drapability of lyocell-interlining bonded fabric correlates with LT, WT, G, 2HG, 2HG5, B, 2HG, WC, and RC of fusible
interlining; LT, EMT, G, 2HG, 2HG5 and RC of lyocell face fabric; LT, EMT, G, 2HG, 2HG5, B, 2HB, LC, RC, and T of lyocell-interlining
bonded fabric. The crease recovery of lyocell-interlining bonded fabric correlates with RT, T, W, WT, G, and 2HG of fusible
interlining; LC, W, LT, EMT, G, 2HG, and 2HG5 of lyocell face fabric; WC, T, LT, G, 2HG, and 2HG5 of lyocell-interlining bonded
fabric. 相似文献
105.
106.
Dyeing of cotton yarn with five water soluble fungal pigments obtained from five fungi 总被引:1,自引:0,他引:1
Palanivel Velmurugan Myung-Jun Kim Jun-Sic Park Kannan Karthikeyan Perumalsamy Lakshmanaperumalsamy Kui-Jae Lee Yool-Jin Park Byung-Taek Oh 《Fibers and Polymers》2010,11(4):598-605
The present study aimed to assess the potentiality of water soluble fungal pigments for dyeing on cotton yarn. Five different
shades of pigments were extracted from Monascus purpureus, Isaria farinosa, Emericella nidulans, Fusarium verticillioides, and Penicillium purpurogenum using ethanol. Maximum concentration of pigment was obtained from Monascus purpureus (red, 25.02±1.6 UA) followed by Penicillium purpurogenum (yellow, 23.05±0.3 UA). The optimum dyeing condition was observed at a pigment concentration of 1 gram, pH 5, temperature
80 °C, time duration 90 min, and a liquor ratio of 1:30 was found to be the optimal for dyeing. Maximum uptake of 80 % was
achieved with Monascus purpureus red pigment. Moreover, the effect of mordant in dyeing was evaluated by different mordanting methods. A strong variation
in shade and color depth could be achieved by using pre-mordanting method with alum and ferrous sulfate giving better wash
fastness properties when compared with post-mordanting or without a mordant. 相似文献
107.
Hyun-wook Kim Ye-in Oh Ji-hye Choi Dae-yong Kim Hwa-young Youn 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(4):551-556
Diagnosis of acute pancreatitis in dogs remains a significant challenge despite the development of advanced diagnostic methodologies. Visual inspection and pancreas biopsy using laparoscopy are generally considered to be procedures free of complications when conducted on healthy animals. However, the usefulness of laparoscopy for diagnosing acute pancreatitis has not been assessed. In the present study, the efficacy of laparoscopy for diagnosing acute pancreatitis in dogs was evaluated in animals with experimentally induced acute pancreatitis. Gross appearance of the pancreatic area was examined by laparoscopy to survey for the presence of edema, adhesions, effusion, pseudocysts, hemorrhage, and fat necrosis. Laparoscopic biopsy was performed and the histopathologic results were compared to those of pancreatic samples obtained during necropsy. The correlation between laparoscopy and histopathologic findings of the pancreas was evaluated. The presence of adhesions, effusion, and hemorrhage in the pancreatic area observed by laparoscopy significantly correlated with the histopathologic results (p < 0.05). There was no significant relationship between the histopathologic and laparoscopic biopsy findings. Results of this study suggested that laparoscopic evaluation of gross lesions has clinical significance although the laparoscopic biopsy technique has some limitations. This method combined with additional diagnostic tools can be effective for diagnosing acute pancreatitis in dogs. 相似文献
108.
The macroscopic motion of liquids on a flat solid surface was manipulated reversibly by photoirradiation of a photoisomerizable monolayer covering the surface. When a liquid droplet several millimeters in diameter was placed on a substrate surface modified with a calix[4]resorcinarene derivative having photochromic azobenzene units, asymmetrical photoirradiation caused a gradient in surface free energy due to the photoisomerization of surface azobenzenes, leading to the directional motion of the droplet. The direction and velocity of the motion were tunable by varying the direction and steepness of the gradient in light intensity. The light-driven motion of a fluid substance in a surface-modified glass tube suggests potential applicability to microscale chemical process systems. 相似文献
109.
Miscanthus sacchariflorus straw was used as a raw material for the manufacture of Miscanthus–wood particle composite board with Douglas-fir particles in ratios of 100/0, 80/20, 60/40, 40/60, 20/80, and 0/100. A commercial phenol–formaldehyde resin was used as a binder at 9 and 11 % for target densities of 0.50 and 0.65 g/cm3, respectively. The effects of the Miscanthus/wood particle ratio on the composite board properties were investigated. In addition, the density profile was also examined to improve the understanding of the composite board manufacturing process. Results indicate that the internal bonding value increased drastically in the board containing up to 50 % wood particles, providing a valuable parameter for subsequent research. The board properties were greatly improved with increasing density and binder addition level. 相似文献
110.
M. S. Kim J. H. Kim M. R. Lee J. H. Kang H. J. Kim H. M. Ko C. H. Choi J. Y. Jung J. T. Koh B. K. Kim H. K. Oh W. J. Kim E. J. Lee S. H. Kim 《Anatomia, histologia, embryologia》2009,38(2):154-160
A disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) have been reported to play a role in the degradation of aggrecan, a major component of cartilage. This study was performed to examine the effects of alendronate on the expression of ADAMTS in developing femoral epiphyseal cartilage. Primary cultured chondrocytes from this cartilage were treated with alendronate in vitro and postnatal day 1 rats were injected subcutaneously with alendronate (1 mg/kg) every second day in vivo . The number of cultured chondrocytes and their aggrecan mRNA levels were unaffected by the alendronate treatment at 10−6 to 10−4 m concentrations. The mRNA levels of ADAMTS-1, -2 and -9 in chondrocytes were also unaffected. However, the levels of ADAMTS-5 and -4 were reduced significantly by the same treatment. The thickness of the proliferating chondrocyte layers and the aggrecan mRNA levels in the epiphysis were unaffected by the alendronate treatment in vivo . However, the hypertrophied chondrocyte layers became significantly thicker, and the size of the secondary ossification centre was reduced significantly by the same treatment ( P < 0.05). Both ADAMTS-4 and -5 mRNA expressions were also reduced significantly in vivo . The immunoreactivity against ADAMTS-4 was seen in hypertrophied chondrocytes and reduced significantly by the alendronate treatment. These results suggested that alendronate can inhibit the degradation of aggrecan in the articular cartilage by downregulating the expression of matrix enzymes such as ADAMTS-4 and -5. 相似文献