465 research outputs found

    Agricultural development and the opportunities for aquatic resources research in China

    Get PDF
    China is a large and rapidly developing country. Fisheries and aquaculture have been prominent sectors in the contribution to GDP and the provision of food security, export revenue, and livelihoods for the poor. The rapid development has come at some cost to the environment and the sustainability of natural resources. Levels of marine fisheries catches are stagnant. Some of the rivers and major lakes are polluted and the restoration of the productivity of these lakes is of key concern. These Proceedings, made up of four papers that leading Chinese experts presented to WorldFish Center in 2002, review four aspects of these trends: agricultural development, environmental issues and the contribution of aquaculture and fisheries to development in China.Agricultural development, Aquaculture development, Living resources, Research, WorldFish Center, WorldFish Center Contrib. No. 1668, China,

    Rapid filling of pipelines with the SPH particle method

    Get PDF
    The paper reports the development and application of a SPH (smoothed particle hydrodynamics) based simulation of rapid filling of pipelines, for which the rigid-column model is commonly used. In this paper the water-hammer equations with a moving boundary are used to model the pipe filling process, and a mesh-less Lagrangian particle approach is employed to solve the governing equations. To assign boundary conditions with time-dependent (upstream) and constant (downstream) pressure, the SPH pressure boundary concept proposed recently in literature is used and extended. Except for imposing boundary conditions, this concept also ensures completeness of the kernels associated with particles close to the boundaries. As a consequence, the boundary deficiency problem encountered in conventional SPH is remedied. The employed particle method with the SPH pressure boundary concept aims to predict the transients occurring during rapid pipe filling. It is validated against laboratory tests, rigid-column solutions and numerical results from literature. Results obtained with the present approach show better agreement with the test data than those from rigid-column theory and the elastic model solved by the box scheme. It is concluded that SPH is a promising tool for the simulation of rapid filling of pipelines with undulating elevation profiles. Keywords: Rapid filling of pipelines; Undulating elevation profile; SP

    Preparation, characterization and anti-ageing activity of Gastrodia elata blume polysaccharide

    Get PDF
    Gastrodia elata Blume polysaccharide (GEP) was extracted and then chemically characterised. Its antioxidant activity was evaluated in vitro and in vivo. The results of the in vitro investigation show that GEP consists of glucose with molecular weight of 875 185 Da and exhibits high hydroxyl radical scavenging, as well as 2,2-diphenyl-1- picrylhydrazyl activity and reducing capacity. For antioxidant activity in vivo, D-galactose-induced-aged mice were orally administered with three different doses of GEP over a period of 6 weeks. The administration of GEP dosedependently increased the body weight gain rates, liver and brain indices, superoxide dismutase and glutathione peroxidase activities, and malondialdehyde levels in the sera and brains of ageing mice. These results suggest that GEP exhibits high antioxidant activity and can retard human ageing associated with free radicals

    Combination of cyclooxygenase-2 inhibitor and doxorubicin increases the growth inhibition and apoptosis in human hepatocellular carcinoma cells

    No full text
    Inhibition of cyclooxygenase (COX)-2 elicits therapeutic effects in solid tumors that are coupled with the inhibition of cell proliferation and induction of apoptosis in tumor cells. Aim: This study was designed to investigate the role of COX-2 inhibitor nimesulide in cell growth and apoptosis of the cultured human hepatocellular carcinoma HepG2 cells. Methods: We performed the MTT assay, flow cytometric analysis and cell morphology study to evaluate growth inhibition and cell apoptosis upon the action of nimesulide alone or along with doxorubicin, a common agent for the treatment of human hepatocellular carcinoma. Results: Our results showed that the treatment of HepG2 cells with more than 50 Β΅M of nimesulide suppressed COX-2 enzyme activity because of reduced PGE2 production, and then induced growth inhibition and cell apoptosis despite no alterations of COX-2 protein expression. Importantly, the combination of 50 Β΅M or 100 Β΅M of nimesulide and low concentrations (5 Β΅M to 20 Β΅M) of doxorubicin resulted in enhanced cell growth inhibition, apoptosis induction and reduced VEGF production. Conclusion: These data suggest synergistic and/or additive effects of COX-2 inhibitors and chemotherapeutic agents, and may provide the rational for clinical studies of COX-2 inhibitors on the treatment or chemoprevention of human hepatocellular carcinoma.Π£Π³Π½Π΅Ρ‚Π΅Π½ΠΈΠ΅ циклооксигСназы-2 (Π¦ΠžΠ“-2) ΠΎΠΊΠ°Π·Ρ‹Π²Π°Π΅Ρ‚ тСрапСвтичСский эффСкт ΠΏΡ€ΠΈ Π»Π΅Ρ‡Π΅Π½ΠΈΠΈ Π±ΠΎΠ»ΡŒΠ½Ρ‹Ρ… с солидными опухолями ΠΈ сопровоТдаСтся сниТСниСм ΠΏΡ€ΠΎΠ»ΠΈΡ„Π΅Ρ€Π°Ρ†ΠΈΠΈ ΠΎΠΏΡƒΡ…ΠΎΠ»Π΅Π²Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ ΠΈ ΠΈΠ½Π΄ΡƒΠΊΡ†ΠΈΠ΅ΠΉ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ·Π°. ЦСль: ΠΈΠ·ΡƒΡ‡Π΅Π½ΠΈΠ΅ Ρ€ΠΎΠ»ΠΈ ΠΈΠ½Π³ΠΈΠ±ΠΈΡ‚ΠΎΡ€Π° Π¦ΠžΠ“-2 β€” нимСсулида Π² процСссах роста ΠΈ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ·Π° ΠΊΡƒΠ»ΡŒΡ‚ΠΈΠ²ΠΈΡ€ΠΎΠ²Π°Π½Π½Ρ‹Ρ… ΠΊΠ»Π΅Ρ‚ΠΎΠΊ Π³Π΅ΠΏΠ°Ρ‚ΠΎΠΊΠ°Ρ€Ρ†ΠΈΠ½ΠΎΠΌΡ‹ Ρ‡Π΅Π»ΠΎΠ²Π΅ΠΊΠ° HepG2. ΠœΠ΅Ρ‚ΠΎΠ΄Ρ‹: для ΠΎΡ†Π΅Π½ΠΊΠΈ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ·Π° ΠΈ угнСтСния роста ΠΊΠ»Π΅Ρ‚ΠΎΠΊ ΠΏΡ€ΠΈ ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠΈ нимСсулида ΡΠ°ΠΌΠΎΡΡ‚ΠΎΡΡ‚Π΅Π»ΡŒΠ½ΠΎ ΠΈ Π² сочСтании с доксорубицином примСняли MTT-Π°Π½Π°Π»ΠΈΠ·, ΠΏΡ€ΠΎΡ‚ΠΎΡ‡Π½ΡƒΡŽ Ρ†ΠΈΡ‚ΠΎΠΌΠ΅Ρ‚Ρ€ΠΈΡŽ ΠΈ стандартныС морфологичСскиС ΠΌΠ΅Ρ‚ΠΎΠ΄Ρ‹. Π Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹: установлСно, Ρ‡Ρ‚ΠΎ ΠΎΠ±Ρ€Π°Π±ΠΎΡ‚ΠΊΠ° ΠΊΠ»Π΅Ρ‚ΠΎΠΊ HepG2 cells нимСсулидом Π² ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†ΠΈΠΈ > 50 ΞΌM ΠΏΡ€ΠΈΠ²ΠΎΠ΄ΠΈΠ»Π° ΠΊ ΡƒΠ³Π½Π΅Ρ‚Π΅Π½ΠΈΡŽ активности Π¦ΠžΠ“-2 Π·Π° счСт сниТСния ΠΏΡ€ΠΎΠ΄ΡƒΠΊΡ†ΠΈΠΈ PGE2 , послС Ρ‡Π΅Π³ΠΎ ΠΎΡ‚ΠΌΠ΅Ρ‡Π°Π»ΠΈ ΠΏΠΎΠ΄Π°Π²Π»Π΅Π½ΠΈΠ΅ роста ΠΈ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ· ΠΊΠ»Π΅Ρ‚ΠΎΠΊ ΠΏΡ€ΠΈ Π½Π΅ΠΈΠ·ΠΌΠ΅Π½Π΅Π½Π½ΠΎΠΌ ΡƒΡ€ΠΎΠ²Π½Π΅ экспрСссии Π¦ΠžΠ“-2. ΠšΠΎΠΌΠ±ΠΈΠ½ΠΈΡ€ΠΎΠ²Π°Π½Π½ΠΎΠ΅ ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ 50 ΞΌM ΠΈΠ»ΠΈ 100 ΞΌM нимСсулида ΠΈ доксорубицина Π² ΠΊΠΎΠ½Ρ†Π΅Π½Ρ‚Ρ€Π°Ρ†ΠΈΠΈ 5–20 ΞΌM обусловило усилСнноС ΡƒΠ³Π½Π΅Ρ‚Π΅Π½ΠΈΠ΅ роста ΠΊΠ»Π΅Ρ‚ΠΎΠΊ, ΠΈΠ½Π΄ΡƒΠΊΡ†ΠΈΠΈ Π°ΠΏΠΎΠΏΡ‚ΠΎΠ·Π° ΠΈ сниТСниС ΠΏΡ€ΠΎΠ΄ΡƒΠΊΡ†ΠΈΠΈ VEGF. Π’Ρ‹Π²ΠΎΠ΄Ρ‹: ΠΏΠΎΠ»ΡƒΡ‡Π΅Π½Π½Ρ‹Π΅ Π΄Π°Π½Π½Ρ‹Π΅ ΡΠ²ΠΈΠ΄Π΅Ρ‚Π΅Π»ΡŒΡΡ‚Π²ΡƒΡŽΡ‚ ΠΎ синСргичСском ΠΈ/ΠΈΠ»ΠΈ Π°Π΄Π΄ΠΈΡ‚ΠΈΠ²Π½ΠΎΠΌ эффСктС ΠΏΡ€ΠΈ ΠΏΡ€ΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠΈ ΠΈΠ½Π³ΠΈΠ±ΠΈΡ‚ΠΎΡ€ΠΎΠ² Π¦ΠžΠ“-2 ΠΈ химиотСрапСвтичСских ΠΏΡ€Π΅ΠΏΠ°Ρ€Π°Ρ‚ΠΎΠ²

    Polarization of AGN in UV Spectral Range

    Full text link
    We present the review of some new problems in cosmology and physics of stars in connection with future launching of WSO. We discuss three problems. UV observations of distant z > 6 quasars allow to obtain information on the soft < 1 KeV X-ray radiation of the accretion disk around a supermassive black hole because of its cosmological redshift. Really the region of X-ray radiation is insufficiently investigated because of high galactic absorption. In a result one will get important information on the reionization zone of the Universe. Astronomers from ESO revealed the effect of alignment of electric vectors of polarized QSOs. One of the probable mechanism of such alignment is the conversion of QSO radiation into low mass pseudoscalar particles (axions) in the extragalactic magnetic field. These boson like particles have been predicted by new SUSY particle physics theory. Since the probability of such conversion is increasing namely in UV spectral range one can expect the strong correlation between UV spectral energy distribution of QSO radiation and polarimetric data in the optical range. In the stellar physics one of the interesting problems is the origin of the X-ray sources with super Eddington luminosities. The results of UV observations of these X-ray sources will allow to find the origin of these sources as accreting intermediate mass black holes.Comment: 6 pages, 3 figure

    A strong steric hindrance effect on ground state, excited state, and charge separated state properties of a CuI-diimine complex captured by X-ray transient absorption spectroscopy

    Get PDF
    Steady-state and transient structures of a copper diimine dye sensitizer on TiO2 nanoparticles undergoing photoinduced interfacial electron transfer are determined.</p
    • …
    corecore