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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

X-ray multiple Diffraction Topographic Imaging Technique For Growth History Study of Habit modifying Impurity Doped crystals

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chemical Research in chinese Universities 2004年第4期20卷 411-416页

作者： LAI X. mA c. k. J. Robert m. c. miller Institute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel crystal characterization instrument has been built up in which a combination of X-ray multiple diffraction and X-ray topography is applied to enabling the cross-correlation between micro-crystallographic symmetry and its spatial dependence in relation to lattice defects. This facility is used to examine, in a self-consistent manner, growth sector-dependant changes to both the crystallographic structure and the lattice defects associated with the action of habit-modifying additives in a number of representative crystal growth systems. In addition, the new instrument can be used to probe micro-crystallographic aspects(such as distortion to crystal symmetry) and relate these in a spatially resolved manner to the crystal defect structure in crystals doped with known habit modifiers.

关键词： X-ray diffraction X-ray multiple diffraction X-ray topography Habit modification crystal growth Growth defects

Fault Diagnosis for a class of Nonlinear Dynamical Systems with Unknown Fault matrix

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Fault Diagnosis for a Class of Nonlinear Dynamical Systems w...

Degree-Based Entropy Descriptors of Graphenylene Using Topological Indices

第十九届中国控制会议

作者： k．c．cheung Department of mechanical Engineering The University of Hong kong Pokfulam Road Hong KongChina

＜正＞In this paper, fault diagnosis for a class of nonlinear dynamical systems is addressed. Different from the work that was done before, the fault matrix is assumed unknown here. Based on estimation errors and qualitative knowledge of systems, a discriminator is constructed to find the true fault matrix. Simulation example of a Dc motor shows the effectiveness of the proposed scheme.

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computer modeling in Engineering & Sciences 2023年第10期137卷 939-964页

作者： m.c.Shanmukha Sokjoon Lee A.Usha k.c.Shilpa muhammad Azeem Department of mathematics Bapuji Institute of Engineering&TechnologyDavanagere577004India Department of computer Engineering(Smart Security) Gachon UniversitySeongnam13120South Korea Department of mathematics Alliance School of Applied MathematicsAlliance UniversityBangalore562106India Department of computer Science and Engineering Bapuji Institute of Engineering&TechnologyDavanagere577004India Department of mathematics Riphah Institute of Computing and Applied SciencesRiphah International UniversityLahore54660Pakistan

Graph theory plays a significant role in the applications of chemistry,pharmacy,communication,maps,and aeronautical *** molecules of chemical compounds are modelled as a graph to study the properties of the *** geometric structure of the compound relates to a few physical properties such as boiling point,enthalpy,π-electron energy,andmolecular *** article aims to determine the practical application of graph theory by solving one of the interdisciplinary problems describing the structures of benzenoid hydrocarbons and *** topological index is an invariant of a molecular graph associated with the chemical structure,which shows the correlation of chemical structures using many physical,chemical properties and biological *** study aims to introduce some novel degree-based entropy descriptors such as ENTSO,ENTGH,ENTHG,ENTSS,ENTNSO,ENTNReZ1,ENTNReZ2 and ENTNSS using the respective topological ***,the above-mentioned entropy measures and physico-chemical properties of benzenoid hydrocarbons are fitted using linear regression models and calculated for graphenylene structure.

关键词： Topological descriptors weighted entropy graphenylene

Afteruse development of former landfll sites in Hong kong

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Journal of Rock mechanics and Geotechnical Engineering 2013年第6期5卷 443-451页

作者： c.T.Wong m.k.Leung m.k.Wong W.c.Tang Architectural Services Department HKSAR Government

Landfll is one of the major methods in disposing of municipal solid waste(mSW) in Hong kong. There are now 13 closed landfll sites in Hong kong, and a restoration program has been launched since 1999 to transform the closed landfll sites back into recreational area. The mSW underneath these closed landfll sites will biodegrade slowly and gradually, releasing toxic gases and leachate. As there have only been a few afteruse development ever completed in Hong kong, this paper describes the consideration in planning and design of two former landfll sites in Hong kong–Ngau chi Wan(NcW) and Jordan Valley(JV) landflls, in particular a discussion on the mSW settlement. Various models in predicting the longterm mSW settlement have been available. This paper reviews the applicability of these models to predict mSW settlement. However, as the predicted settlements can be signifcantly in error, they need sitespecifc calibration and validation. This paper therefore presents the settlement monitoring data in these former landfll sites over the last 30 years, and suggests modifying the Bjarngard and Edgers’ method for estimating this long-term settlement as well as the effect of additional surcharge due to afteruse development. Based on the regression of these data, compression indices cce and c at different stages of the settlement in the modifed method have been calibrated and validated.

关键词： Afteruse development closed landflls municipal solid waste(mSW) settlement modifed Bjarngard and Edgers' method

Analysis Scheme for Density modulation Experiments to Study Particle confinements

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Plasma Science and Technology 2006年第1期8卷 65-71页

作者： k. TANAkA c. mIcHAEL k. kAWANATA T. TOkUZAWAI m. SHOJI k. TOI 高翔揭银先 National Institute for Fusion Science Toki 509-5292 Japan Institute of Plasma Physics Chinese Academy of Science Hefei 230031 China

Density modulation experiments are powerful experimental schemes for the study of particle transport. The diffusion coefficients （D） and convection velocity （V）, which cannot be evaluated from the particle balance in the equilibrium state, can be obtained separately. Further, the estimated values of D and V are determined independent of the absolute value of the particle source rate, which is difficult to obtain experimentally. However, the sensitivities and interpretation of D and V from the modulation experiments need to be considered. This paper describes numerical techniques for solving the particle balance equation of the modulation components. Examples of the analysis are shown regarding the data of LHD experiments, and the results of the modulation experiments are discussed.

关键词： density modulation, particle confinements, diffusion coefficient convection velocity

The Long Term Sustainability of the Victoria Harbour Relies on the Successful Implementation of the Harbour Area Treatment Scheme

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The Long Term Sustainability of the Victoria Harbour Relies ...

Biocompatibility and biotoxicity of in-situ synthesized carboxylated nanodiamond-cobalt oxide nanocomposite

第四届粤港澳可持续发展研讨会

作者： Andrew N Y Yuen Freeman c m cheung Amy k Y cheung Drainage Services Department The Government of the Hong kong SAR ENSR Asia(Hk)Limited Hong kong

Substantial population growth in the past decades around Victoria Harbour re- sulted in water quality deterioration from the discharge of preliminary treated sewage into the *** Harbour Area Treatment Scheme(HATS)is a centralised sewage collection and treatment scheme for areas on both sides of Victoria *** of this world-class sewage treatment infrastructure is being carried out in several stages,viz Stage 1,Stage 2A and Stage *** 1 of HATS involved the construction of a 23.6 km-long system of tunnels deep underground,carrying currently 1.4 million tonnes of sewage each day from kowloon and the northeastern part of Hong kong Island to a sewage treatment plant at Stonecutters Island for chemically enhanced primary treatment before *** 1 of HATS has brought about no- ticeable water quality improvement to the Victoria Harbour since its full commissioning in 2001 by treating 75% of the harbour sewage,but more needs to be done to restore the Harbour to a healthier *** 2A of HATS will upgrade the preliminary treatment works around the northern and southwestern shore of Hong kong Island and construct a 21 km-long deep tunnel system to convey the sewage from Hong kong Island to Stonecutters Island Sewage Treatment Works(ScISTW),where the existing chemical treatment facilities will be expanded and new disinfection facilities *** planning and design for this phase is well underway with the aim of commissioning Stage 2A in *** 2B of HATS will involve the provision of bio- logical treatment at the ScISTW to further improve the effluent *** timing of the Stage 2B implementation will be decided upon a review of water quality trends,population increases and sewage flow build up to be undertaken in *** harbour water quality will benefit society in many different ways,including for example,enhanced recreational opportuni- ties,scenic quality,aesthetics,public health and safety as well as ecol

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Journal of materials Science & Technology 2017年第8期33卷 879-888页

作者： L.Syam Sundar Naser A.Anjum m.c.Ferro Eduarda Pereira manoj k.Singh A.c.m.Sousa TEmA-Department of mechanical Engineering University ofAveiroAveiroPortugal cESAm-centrefor Environmental&marine Studies and Department of chemistry University of Aveiro3810-193AveiroPortugal cIcEcO Department of Material Engineering and CeramicsUniversity of AveiroPortugal

A nanocomposite that incorporates cobalt oxide（co3O4） and nanodiamond（ND） can present both high magnetism（co3O4） and high hardness（ND）. ND particles have potential applications in a variety of fields such as protein immobilization, biosensors, therapeutic molecule delivery and bio-imaging. However,limited information is available in literature on the in-situ synthesis of biocompatible magnetic materials and also on their potential biotoxicity as a result of their entry into environmental compartments and subsequent interaction with biota. In this work, a new kind of bio-compatible magnetic material –carboxylated nanodiamond（c ND） and co3O4 was synthesized to obtain the c ND-co3O4 *** synthesis procedure involved in-situ and chemical reduction of cobalt chloride（cocl（26）H2O） and sodium borohydrate（NaBH4）. The synthesized cND-co3O4 nanocomposite was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The cyto-genotoxicity of the synthesized nanocomposite material was studied by using onion（Allium cepa L.） as a test model with concentrations of 5, 10 and 20 μg/ml. The study was also extended to cND and co3O4 materials for comparison purpose. co3O4 and cND exhibited their contrasting effects on mitosis and other cyto-genotoxic indices studied herein. This work provided fundamental data on the synthesis and the bio-toxicity of the c ND-co3O4 nanocomposite, which, in turn, can help to expand their multidisciplinary applications.

关键词： Nanodiamond cobalt oxide Nanodiamond Nanocomposite Bio-toxicity Allium cepa

PREcIPITATION BEHAVIOR IN A cu-Sn-Ni-Zn-P LEAD FRAmE mATERIAL

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Acta metallurgica Sinica(English Letters) 2003年第3期16卷 155-160页

作者： W.H.Tian c.k.Yan m.Nemoto Department of materials Physics and chemistry University of Science and Technology BeijiingBeijing 100083ChinaInstitute of Metal ResearchThe Chinese Academy of SciencesShenyang 110016ChinaSasebo National College of Technology Okishin 1-1 Sasebo 857-1193 Japan

Transmission electron microscopy (TEm) observations were carried out for examining the precipitation behavior in a cu-Sn-Ni-Zn-P lead frame material. TEm observations revealed that the precipitate is hexagonal Ni5P2 and the orientation relationship between the cu matrix and Ni$Pi precipitate is (111)fcc//(0001)hcp, [101]fcc//[1120]hcp, where the suffix fcc denotes the cu matrix and hep denotes the hexagonal Ni5P2 precipitate. The Ni5P2 precipitate is ovoidal in shape at the beginning of aging at lower temperature. By prolonging the aging time or increasing the aging temperature, Ni5P2 precipitate grows and shows a rod-like shape. The Ni added cu based lead frame material has a comparative mechanical properties with that of TAmAc15 which has been developed and used in electrical industry.

关键词： lead frame materials mechanical properties atom diffusion precipitate transmission electron microscopy