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Effects of 2,3,7,8-TcDD and benzo[a]pyrene on modulating vitellogenin expression in primary culture of crucian carp (carassius auratus) hepatocytes

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chinese Science Bulletin 2004年第22期49卷 2372-2378页

作者： LIANGYong c.k.c.Wong XUYing M.H.Wong StatekeyLaboratoryofFreshwaterEcologyandBiotechnology InstituteofHydrobiologyChineseAcademyofSciencesWuhan430072China//GraduateSchoolofChineseAcademyofSciencesBeijing100039China DepartmentofBiology HongKongBaptistUniversityKowloonTongHongKong StatekeyLaboratoryofFreshwaterEcologyandBiotechnology InstituteofHydrobiologyChineseAcademyofSciencesWuhan430072China

Vitellogenin (Vtg) is the precursor of yolk protein. Its expression and secretion are estrogen-regulated and are crucial for oocyte maturation. An in vitro xenoestro- gen screening model was established by measuring Vtg in- duction in cultured primary hepatocytes from crucian carp. Vtg production was detected by biotin-avidin sandwich ELISA method while Vtg and cytochrome P4501A1 (cYP1A1) mRNA induction were measured by semi- quan- titative PcR-primer dropping technique. Vtg and Vtg mRNA were dose-dependently induced by diethylstilbestrol (DES, 0.2—200 ng/mL) in hepatocytes of crucian carp. co-treatment of the DES-induced hepatocytes with either 2,3,7,8-TcDD (TcDD, 0.1—4 pg/mL) or benzo[a]pyrene (B[a]P, 5—1000 ng/mL) resulted in a reduction of Vtg pro- duction and an increment of cYP1A1 mRNA expression both in a dose dependent manner, indicating the anti-estro- genic effects of the compounds. However, at lower tested concentrations, TcDD (0.1, 0.2 pg/mL), B[a]P (5 ng/mL) seemed to have a potentiating effect on Vtg expression and secretion, although by their own these compounds had no observable estrogenic effect on Vtg induction. Tamoxifen (a selective estrogen receptor modulators, 1 nmol/L—1 μmol/L), and β-naphtho-flavone (β-NF, an aryl hydrocarbon receptor inducing compounds, 2.5—1000 ng/mL) also were employed to study the possible interactions in DES-induced Vtg ex- pression. In co-treatment of the DES-induced hepatocytes with β-NF or tamoxifen, the decrease in Vtg production did parallel induction of cYP1A1 for β-NF, but tamoxifen inhib- ited Vtg induction did not parallel induced cYP1A1 expres- sion in all test concentrations. On the contrary, it was found that in co-treatment of the TcDD-induced hepatocytes with DES, TcDD induced cYP1A1 mRNA production was inhib- ited by DES also. These results implicated a possible cross talk between estrogen receptor- and aryl hydrocarbon re- ceptor-mediated pathways in the hepatocytes.

关键词： 2,3,7,8-TcDD 苯并[a]芘卵黄蛋白原鲫鱼鲤鱼肝细胞 cYP1A1 卵黄蛋白质异种雌激素

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Artificial neural network approach for rheological characteristics of coal-water slurry using microwave pre-treatment

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International Journal of Mining Science and Technology 2017年第2期27卷 379-386页

作者： B.k.Sahoo S.De B.c.Meikap Department of chemical Engineering Indian Institute of Technology Research and Development centre for Iron and Steel Steel Authority of India Limited chemical Engineering School of Engineering Howard College University of Kwazulu-Natal

Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheology characteristic for microwave pre-treatment of coal-water slurry(cWS) was performed in an online Bohlin viscometer. The non-Newtonian character of the slurry follows the rheological model of Ostwald de Waele. The values of n and k vary from 0.31 to 0.64 and 0.19 to 0.81 Pa·sn,respectively. This paper presents an artificial neural network(ANN) model to predict the effects of operational parameters on apparent viscosity of cWS. A 4-2-1 topology with Levenberg-Marquardt training algorithm(trainlm) was selected as the controlled ANN. Mean squared error(MSE) of 0.002 and coefficient of multiple determinations(R^2) of 0.99 were obtained for the outperforming model. The promising values of correlation coefficient further confirm the robustness and satisfactory performance of the proposed ANN model.

关键词： Microwave pre-treatment coal-water slurry Apparent viscosity Artificial neural network Back propagation algorithm

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LOcAL MEDIAN ESTIMATION OF VARIANcE FUNcTION

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Acta Mathematica Scientia 2004年第1期24卷 28-38页

作者：杨瑛 W.c.Ip Y.k.kwan P.Y.k.kwan School of Mathematical Sciences Peking University Beijing 100871 China Department of Applied Mathematics The Hong Kong Polgytechnic University Hung Hom Kowloon Hongkong China

This paper considers local median estimation in fixed design regression problems. The proposed method is employed to estimate the median function and the variance function of a heteroscedastic regression model. Strong convergence rates of the proposed estimators are obtained. Simulation results are given to show the performance of the proposed methods.

关键词： Heteroscedasticity nonparametric median regression strong convergence rate variance function local median estimation

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Propagation of Solitary Pulses in Optical Fibers with Both Self-Steepening and Quintic Nonlinear Effects

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communications in Theoretical Physics 2014年第6期61卷 735-741页

作者：李金花 c.Rogers k.W.chow k.S.chiang School of Physics and Optoelectronic Engineering Nanjing University of Information Science and Technology Australian Research council centre of Excellence for Mathematics & Statistics of complex Systems School of Mathematics The University of New South Wales Department of Mechanical Engineering University of Hong Kong Department of Electronic Engineering City University of Hong Kong

Pulse dynamics and stability in optical fibers in the presence of both self-steepening and quintic nonlinear effects are analyzed. Propagating profiles of the quintic derivative nonlinear Schr¨odinger model are isolated via two invariants of motion. The resulting canonical equation admits exact periodic propagating patterns in terms of the Jacobi elliptic functions, and solitary pulses are recovered in the long wave limit, i.e. degenerate cases of periodic profiles where each pulse is widely separated from the adjacent ones. Two families of such exact wave profiles are identified. The first one has a precise constraint concerning the magnitude of self-steepening and quintic nonlinear effects, while the second one permits more freedom. The reduction to the well established temporal soliton in an optical fiber waveguide in the absence of self-steepening and quintic nonlinearity is demonstrated explicitly. Numerical simulations are performed to identify regimes of parameter values where robust propagation patterns exist.

关键词： cubic-quintie nonlinear Schrodinger equation self-steepening pulse propagation

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Analytical and Numerical Modelling of FRP Debonding from concrete Substrate under Pure Shearing

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 142-148页

作者： PAN Jinlong XU Zhun c k Y Leung LI Zongjin key Laboratory of concrete and Pre-stressed concrete Structures of Ministry of Education Southeast UniversityNanjing 210096 Dept.of civil and Environmental Engineering Hong Kong University of Science and TechnologyHongKongChina

External bonding of fiber reinforced polymer （FRP） composites on the concrete structures has been proved to be an effective and efficient way to strengthen concrete structures. For a FRP strengthened concrete beam, it is usually observed that the failure occurs in the concrete and a thin layer of concrete is attached on the surface of the debonded FRP plate. To study the debond behavior between concrete and FRP composites, an analytical model based on the three-parameter model is developed to study the debonding behavior for the FRP-to-concrete joint under pure shearing. Then, nonlinear FEM analysis is conducted to verify the PrOposed analytical model. The FEM results shows good agreement with the results from the model. Finally, with the analytical model, sensitivity analyses are performed to study the effect of the interracial parameters or the ~eometric parameters on the debondin~ behavior.

关键词： FRP composites debonding behavior analytical model nonlinear FEM analysis

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PRELIMINARY REPORT ON SUSPENSION cULTURE OF cLON OF PORPHYRA YEZOENSIS cONcHOSPORANGIAL FILAMENTS IN THE PRODUcTION OF cONcHOSPORES FOR PURPLE LAVER AQUAcULTURE

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海洋与湖沼 1996年第6期 668-669页

作者： c.k.Tseng

For the aquaculture of Porphyra, seedling is a key link. At present,carpospores of the hara are sown on molluscan shells and the conchocelis stage is produced. The latter gives rise to the concho sporangial filaments, finally produces conchospores. Production nets are provided on which the liberated conchospores attach and grow. The whole process takes 5 - 6 months, and a large area of ponds have to be devoted to culture of the conchocelis in shells. Iwasaki et al. (1963) reported on cultivation of the free-living conchocelis. But it still had to be sown on molluscan shells and cultivated in ponds. It seems that only the conchocelis growing in shells are capable of producing conchospores. At present sithelar method is employed in china. Therefore it is of great importance whether suspension cultivation of concho-sprangial filaments without the shells are able to produce conchospores.

关键词： Porphyra yezoensis clon of concho-sporangial filaments Suspension culture

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STUDIES ON THE GEPPELLA(cHLOROPHYTA) OF XISHA ISLANDS,SOUTH cHINA SEA

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Journal of Oceanology and Limnology 1983年第2期1卷 190-197页

作者： c.k.Tseng Institute of Oceanology Academia Sinica

The genus Geppellais a small group of tropical and subtropical *** was establishedby Boergesen in 1940 on the basis of its uncalciferous frond and its characteristic of annularattachments of the filaments,with *** Boergesen as the type of the *** four more species have been described,namely,*** Dawson(1959),***-caulos cribb(1960),*** Tanaka(1963),and *** Tanaka et Itono(1977).The species *** was reported by Dawson from Isla San Francisco(Gulf of california)and the Marshall Islands,central Pacific,and later removed by Tanaka and Itono(1977)from the genus Geppella because of the absence of blade and of annular attachments of

关键词： cHLOROPHYTA OF XISHA ISLANDS,SOUTH cHINA SEA STUDIES ON THE GEPPELLA

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Joint MAP channel estimation and data detection for OFDM in presence of phase noise from free running and phase locked loop oscillator

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Digital communications and Networks 2021年第1期7卷 55-61页

作者： kamayani Shrivastav R.P.Yadav k.c.Jain Department of Electronics and communication Malaviya National Institute of Technology302017India Department of Matiiematics Indian Institute of Information TechnologyKotaIndia

This paper addresses a computationally compact and statistically optimal joint Maximum a Posteriori(MAP)algorithm for channel estimation and data detection in the presence of Phase Noise(PHN)in iterative Orthogonal Frequency Division Multiplexing(OFDM)receivers used for high speed and high spectral efficient wireless communication *** MAP cost function for joint estimation and detection is derived and optimized further with the proposed cyclic gradient descent optimization *** proposed joint estimation and detection algorithm relaxes the restriction of small PHN assumptions and utilizes the prior statistical knowledge of PHN spectral components to produce a statistically optimal *** frequency-domain estimation of channel Transfer Function(cTF)in frequency selective fading makes the method simpler,compared with the estimation of channel Impulse Response(cIR)in the time *** different time-varying PHN models,produced by Free Running Oscillator(FRO)and Phase-Locked Loop(PLL)oscillator,are presented and compared for performance difference with proposed OFDM *** results for joint MAP channel estimation are compared with cramer-Rao Lower Bound(cRLB),and the simulation results for joint MAP data detection are compared with“NO PHN"performance to demonstrate that the proposed joint MAP estimation and detection algorithm achieve near-optimum performance even under multipath channel fading.

关键词： Orthogonal frequency division multiplexing Phase noise Free running oscillator Phase-locked loop oscillator Maximum a posteriori channel estimation Data detection

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Provenance bias between detrital zircons from sandstones and river sands:A quantification approach using 3-D grain shape,composition and age

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Geoscience Frontiers 2020年第3期11卷 835-842页

作者： V.Markwitz c.L.kirkland k.Gessner School of Earth Sciences The University of Western AustraliaWA6009Australia School of Earth and Planetary Science Centre for Exploration Targeting-Curtin NodeCurtin UniversityWA6045Australia Geological Survey of Western Australia 100 Plain StreetEast PerthWA6004Australia

Preservation bias may significantly impact the application of detrital zircon geochronology in reconstructing Earth surface *** we compare detrital zircons from the actively eroding Murchison River channel in Western Australia with Ordovician fluvial sediments that have drained similar source rocks along the western margin of the West Australian *** addition to standard analysis of detrital zircon age spectra we apply multivariate statistics to test the relation between 3-D grain shape,U-content and U-Pb ages,with the objective to quantify differences between both sample groups and track preservation along the transport pathway of the Murchison *** results show that zircon grains in modern river sands display an upstream trend toward larger surface areas,volume equivalent diameters and grain widths,as well as toward higher U-contents and lower apparent grain densities.3-D grain shape,size and age spectra of Murchison River zircons evolve consistently downstream,but even at the river outlet remain distinct from the Ordovician samples,as a less mature representation of *** interpret Ordovician river zircons to represent a significantly depleted subset from which up to 22% of the zircon population may have been lost compared to the actively transported detrital *** discrepancy between the characteristics of detrital zircons in modern active rivers and ancient fluvial Ordovician sandstones demonstrates a bias that could be relevant for other source-sink detrital transport systems throughout Earth history.

关键词： X-ray tomography Detrital Zircon Grain shape Preservation Fluvial

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Restorating marine coastal ecosystem health as a new goad for integrated catchment management in Tolo Harbour,Hong kong,china

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chinese Journal of Population,Resources and Environment 2004年第2期2卷 11-19页

作者： Lam k.c. Department of Geography and Resoure management The Chinese University of Hong Kong.ShatinNew TerritoriesHong KongChinahe paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management in coastal area of the Tolo Harbour. The present goal of integrated catchment management (ICM) in the Tolo Harbour is to meet with Water Quality Objectives. The performance of an ICM plan Tolo Harbour Action Plan (THAP) is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988 some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical chemical and biological indicators although some reverse fluctuations in some periods exist. However this can only be considered as the first sign of the ecosystem health restoration since ecosystem health covers not only physical chemical and biological aspects of an ecosystem but also ecosystem-service-function aspect. It is recommended to take the restoration and protection of marine coastal ecosystem health as a new goal instead of water quality objective management for integrated catchment management in Tolo Harbour catchment. Steps to further improve the marine coastal ecosystem health of Tolo harbour are discussed in the paper.

The paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management, in coastal area of the Tolo Harbour. The present goal of integrated catchment management (IcM) in the Tolo Harbour is to meet with Water Quality Objectives. The performance of an IcM plan, Tolo Harbour Action Plan (THAP), is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988, some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical, chemical and biological indicators, although some reverse fluctuations in some periods exist. However, this can only be considered as the first sign of the ecosystem health restoration, since ecosystem health

关键词： Marine coastal ecosystem health integrated catchment management pollution loading indicator Tolo Harbour Action Plan.

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