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101.
Palanivel Sathishkumar Kannan Balan Thayumanavan Palvannan Seralathan Kamala‐Kannan Byung‐Taek Oh Susana Rodríguez‐Couto 《洁净——土壤、空气、水》2013,41(7):665-672
Laccase from the white‐rot fungus Pleurotus florida, produced under solid‐state fermentation conditions, was used for the decolorization of reactive dye Remazol Brilliant Blue R (RBBR). RBBR was decolorized up to 46% by P. florida laccase alone in 10 min. In the presence of N‐hydroxybenzotriazole (HBT), the rate of decolorization was enhanced 1.56‐fold. Central composite design of response surface methodology with four variables namely, dye, enzyme, redox mediator concentrations, and time at five levels was applied to optimize the RBBR decolorization. The predicted optimum level of variables for maximum RBBR decolorization (87%) was found to be 52.90 mg L?1 (RBBR), 1.87 U mL?1 (laccase), 0.85 mM (HBT), and 7.17 min (time), respectively. The validation results showed that the experimental value of RBBR decolorization (82%) was close to the predicted one. The disappearance of C–N and C–X groups, and a small shift in N–H groups in Fourier‐transform infra red (FTIR) spectroscopy confirms the degradation of RBBR chromophore by laccase enzyme. The phytotoxicity of RBBR was considerably reduced after the treatment with laccase. RBBR decolorization kinetics; Km and Vmax were calculated to be 145.82 mg L?1 and 24.86 mg L?1 min, respectively. 相似文献
102.
The Hongseong area, located in the western Gyeonggi Massif, South Korea, can be correlated with the northern margin of the South China block (Yangtze Craton). This area experienced Neoproterozoic igneous activity related to subduction before the amalgamation of Rodinia. Several isolated, lenticular, and serpentinized ultramafic–mafic bodies occur in the Hongseong area. The Baekdong body, one of the largest ultramafic bodies, has been highly deformed and metamorphosed to eclogite- and granulite-facies. The petrogenesis and tectonic environment of the Baekdong rocks are assessed using the composition of unaltered cores of spinel and olivine grains, and show that these rocks represent the mantle section of a suprasubduction ophiolite. The rocks originated from oceanic lithosphere that formed during the transition from nascent back-arc to mature island arc, related to subduction roll-back. During the back-arc stage, Al-rich spinel harzburgite formed through melt–rock interaction caused by the intrusion of magma. This magma was produced in small amounts, by less than 10% of partial melting of the wedge mantle. Subsequently, during the mature island arc stage, Cr-rich spinel dunite formed through melt–rock interaction caused by the intrusion of relatively evolved magma that formed by 30–35% partial melting due to a high input of volatiles from the subducted slab and sediments. The Baekdong ultramafic rocks, together with the Bibong ultramafic rocks, indicate that a suprasubduction tectonic setting prevailed before the amalgamation of Rodinia (at 860–890 Ma) in the Hongseong area, which may be an extension of the northern margin of the Yangtze Craton. 相似文献
103.
104.
Bo-Ram Ye Junseong Kim Min-Sun Kim Jiyi Jang Chulhong Oh Do-Hyung Kang Zhong-Ji Qian Won-Kyo Jung Il-Whan Choi Soo-Jin Heo 《Ocean Science Journal》2013,48(4):339-348
We demonstrated that an extract from Pylaiella littoralis, collected from the Federate States of Micronesia (FSM), could inhibit the proliferation of tumor cells. P. littoralis extract (PLE) showed anti-proliferative activities in the tumorigenic cells tested, ranging from 20.2% to 67.9%. The highest inhibitory activity, in HT-29 cells, was selected for further experiments. PLE showed no cytotoxic effect in normal cells and inhibited the growth of HT-29 cells depending on concentration and incubation time. PLE-treated HT-29 cells showed the typical morphological characteristics of apoptosis, such as apoptotic body formation and DNA fragmentation. PLE also induced mitochondrial membrane potential depolarization and resulted in increased mitochondrial membrane permeability, compared with untreated cells. PLE decreased Bcl-2 protein and increased Bax protein expression, activating caspase-3 and poly (ADP-ribose) polymerase (PARP) expression via the caspase pathway. PLE also increased the phosphorylation of c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK), and it reduced cell viability in treatment cells with specific inhibitors such as PD98059 (a specific inhibitor of ERK), SP600125 (a specific inbibitor of JNK), and SB 203580 (a specific inbibitor of p38 MAPK). via the the mitogen-activated protein kinases (MAPKs) pathway. These results suggest that PLE inhibits the proliferation of HT-29 cells by affecting the caspase and MAPK pathways involved in the induction of apoptosis. Thus, we suggest that P. littoralis extract might be potential candidate agents for the treatment of human colorectal cancer. 相似文献
105.
Application of hybrid‐simulation to fragility assessment of the telescoping self‐centering energy dissipative bracing system 下载免费PDF全文
Viswanath Kammula Jeffrey Erochko Oh‐Sung Kwon Constantin Christopoulos 《地震工程与结构动力学》2014,43(6):811-830
Substructure hybrid simulation has been the subject of numerous investigations in recent years. The simulation method allows for the assessment of the seismic performance of structures by representing critical components with physical specimens and the rest of the structure with numerical models. In this study the system level performance of a six‐storey structure with telescoping self‐centering energy dissipative (T‐SCED) braces is validated through pseudo‐dynamic (PsD) hybrid simulation. Fragility curves are derived for the T‐SCED system. This paper presents the configuration of the hybrid simulation, the newly developed control software for PsD hybrid simulation, which can integrate generic hydraulic actuators into PsD hybrid simulation, and the seismic performance of a structure equipped with T‐SCED braces. The experimental results show that the six‐storey structure with T‐SCED braces satisfies performance limits specified in ASCE 41. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
106.
Seongil Jo Yaeji Lim Jaeyong Lee Hyun-Suk Kang Hee-Seok Oh 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(3):205-212
In this paper, we apply three different Bayesian methods to the seasonal forecasting of the precipitation in a region around Korea (32.5°N?C42.5°N, 122.5°E-132.5°E). We focus on the precipitation of summer season (June?CJuly?CAugust; JJA) for the period of 1979?C2007 using the precipitation produced by the Global Data Assimilation and Prediction System (GDAPS) as predictors. Through cross-validation, we demonstrate improvement for seasonal forecast of precipitation in terms of root mean squared error (RMSE) and linear error in probability space score (LEPS). The proposed methods yield RMSE of 1.09 and LEPS of 0.31 between the predicted and observed precipitations, while the prediction using GDAPS output only produces RMSE of 1.20 and LEPS of 0.33 for CPC Merged Analyzed Precipitation (CMAP) data. For station-measured precipitation data, the RMSE and LEPS of the proposed Bayesian methods are 0.53 and 0.29, while GDAPS output is 0.66 and 0.33, respectively. The methods seem to capture the spatial pattern of the observed precipitation. The Bayesian paradigm incorporates the model uncertainty as an integral part of modeling in a natural way. We provide a probabilistic forecast integrating model uncertainty. 相似文献
107.
This paper investigates the impact of the Madden-Julian Oscillation (MJO) on the diurnal cycle of rainfall over the western Maritime Continent during the austral summer. For this purpose, cyclostationary empirical orthogonal function analysis is applied to the tropical rainfall measuring mission rain rate and the Japanese Reanalysis-25 data for the period 1998–2008. The real-time multivariate MJO index by Wheeler and Hendon (Mon Wea Rev 132:1917–1932, 2004) is adopted to define the intensity and the phase of MJO. It is demonstrated that the hourly maximum rain rate over the domain tends to increase when convectively active phase of MJO approaches the Maritime Continent. In contrast, the hourly maximum rain rate tends to decrease when convectively suppressed phase of MJO resides over the region. The changes in the rain rate due to MJO differ over the ocean and the land. This difference is the greatest when the MJO is in the mature stage. Throughout the day during this stage, terrestrial rain rates show minimum values while diurnally varying oceanic rain rates record maximum values. Thus, precipitation becomes more intense in the morning over the Java Sea and is weakened in the evening over Borneo and Sumatra during the mature stage of MJO. During the decaying stage of MJO over the Maritime Continent, the diurnal cycle of precipitation weakens significantly over the ocean but only weakly over land. Analyses suggest that the anomalous lower level winds accompanied by MJO interact with the monsoonal flow over the Maritime Continent. Westerlies induced by MJO convection in the mature stage are superimposed on the monsoonal westerlies over the equator and increase wind speed mainly over the Java Sea due to the blocking effect of orography. Mountainous islands induce flow bifurcation, causing near-surface winds to converge mainly over the oceanic channels between two islands. As a result, heat flux release from the ocean to the atmosphere is enhanced by the increased surface wind resulting in instability as described in the wind-induced surface heat exchange mechanism. This may contribute to heavy rainfall over the Java Sea in the morning during the mature stage. On the other hand, convergence and vertical velocity over the islands, which play important roles in inducing nighttime rainfall, tend to be weak in the evening during the mature stage of MJO. Strong westerlies arising from MJO and the seasonal flow during the mature stage tend to interrupt convergence over islands. This interruption of convergence by MJO gives rise to decreased rain rates over the land regions. 相似文献
108.
Jae-Won Oh Hyung-Woo Kim Sup Hong Ki-Young Sung Dae-Sung Bae 《Marine Georesources & Geotechnology》2017,35(1):120-126
To design the deep-sea mining robot, it is essential to analyze the tribological characteristics of its roller. In this study, we introduced the dynamic simulation model to analyze the tribological characteristics of the roller for deep-sea mining robot, considering the temperature, viscosity, viscous damping force, and gap size between the inner and outer rib seals. Effective viscosity changes with gap size in micro/nanoscale while the effective viscosity is equal to the kinematic viscosity in macroscale. For the stable operation of the roller, the effective viscosity must be less than the critical viscosity. As the gap size decreases, the effective viscosity increases while the critical viscosity decreases. This study shows that the gap size between the inner and outer rib seals of roller is the most dominant factor in designing the roller for deep-sea mining robot to use at relatively low temperatures that are found in the deep-sea environments. 相似文献
109.
Undrained shear strength is a fundamental parameter for estimating the stability of soft soils. This study explores the relationship between undrained shear strength, void ratio, and shear wave velocity for saturated and normally consolidated clay specimens. The undrained shear strength void ratio-shear wave velocity relationship was correlated to empirically determined parameters of selected marine clay specimens. To verify the proposed relationship between undrained shear strength and shear wave velocity, in situ flat dilatometer tests were used for determining the undrained shear strength, and downhole tests were used to assess the shear wave velocity on a natural soil deposit at various depths. The undrained shear strength estimated from the in situ shear wave velocities was compared to the undrained shear strength obtained in the field. The results show that the inferred undrained shear strength yield similar values and follow the same trends as the in situ undrained shear strength data. This method using shear wave velocity can help to nondestructively estimate the undrained shear strength of soft soils in the field and be used in both on-shore and off-shore geotechnical engineering projects. 相似文献
110.
SeongEun Kim HanJu Kim HoJin Bae Hyeong-Gi Kim Chul-Woong Oh 《Ocean Science Journal》2017,52(2):257-265
Growth and reproduction of the Japanese mantis shrimp, Oratosquilla oratoria, were investigated in the Tongyeong, Korea from July 2014 to August 2015. A total of 2,621 samples (1,380 females and 1,241 males) were collected during the study period. Females were observed more frequently than males. The mean body length (BL) was 128.5 ± 0.38 mm in females and 126.9 ± 0.42 mm in males. The mean body weight (BW) was 31.2 ± 0.28 g in females and 31.1 ± 0.32 g in males. There was a significant difference in the length-frequency distribution between females and males. The relationship between BL and BW was lnBW = 2.85 × lnBL - 10.43 for females and lnBW = 2.87 × lnBL -10.52 for males. The gonadosomatic index (GSI) varied on a monthly basis. The GSI reached a maximum in May and a minimum in November. The highest values of the GSI coincided with the spawning period of O. oratoria. Larger individuals of O. oratoria have their spawning season earlier than smaller ones. The size at sexual maturity of females was estimated as 96.5 mm. The Von Bertalanffy growth function parameters were BL∞ = 184.5 mm, K = 0.72 year?1, C = 0.36 and WP = 0.45 for females and BL∞ = 183.75 mm, K = 0.82 year?1, C = 0.38 and WP = 0.22 for males. The growth of males was slightly faster than females. The present study will help with the fisheries management of O. oratoria based on ecological parameters. 相似文献