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Molecular Plant 2016年第3期9卷 428-436页

作者： J. Bohm S. Scherzer S. Shabala E. Krol E. Neher t.D. Mueller R. Hedrich Julius-yon-Sachs Institute Department for Molecular Plant Physiology and Biophysics University of Wurzburg Julius-von-Sachs Platz 2 97082 Wurzburg Germany School of Land and Food University of Tasmania Hobart TAS 7001 Australia Zoology Department College of Science King Saud University PO Box 2455 Riyadh 11451 Saudi Arabia Department for Membrane Biophysics Max Planck Institute for Biophysical Chemistry 37077 Goettingen Germany

the animal diet of the carnivorous Venus flytrap, Dionaea muscipula, contains a sodium load that enters the capture organ via an HKt1-type sodium channel, expressed in special epithelia cells on the inner trap lobe surface. DmHKt1 expression and sodium uptake activity is induced upon prey contact. Here, we analyzed the HKt1 properties required for prey sodium osmolyte management of carnivorous Dionaea. Analyses were based on homology modeling, generation of model-derived point mutants, and their functional testing in Xenopus oocytes. We showed that the wild-type HKt1 and its Na^＋- and K^＋-permeable mutants function as ion channels rather than K^＋ transporters driven by proton or sodium gradients. these structural and biophysical features of a high-capacity, Na^＋-selective ion channel enable Dionaea glands to manage prey-derived sodium loads without confounding the action potential-based information management of the flytrap.

关键词： sodium channel HKt1 Dionaea muscipula action potential glands sodium uptake

Anticancer activity of Salvia officinalis essential oil and its principal constituents against hormone-dependent tumour cells

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Asian Pacific Journal of tropical Biomedicine 2019年第1期9卷 24-28页

作者： G.Privitera t.Luca S.Castorina R.Passanisi G.Ruberto E.Napoli Fondazione Mediterranea "G.B.Morgagni" Department of Medical and Surgical Sciences and advanced technologies University of Catania Institute of Biomolecular Chemistry Italian National Research Council ICB-CNR

Objective: to investigate the in vitro antiproliferative action of essential oil from Salvia officinalis L.(S. officinalis) grown in Sicily(Italy), and its main components on hormone-dependent cancer cell lines. Methods: S. officinalis essential oil was prepared by hydrodistillation. the actions of the S. officinalis essential oil and its three principal components(毩-thujone, 1,8-cineole and camphor) were evaluated in LNCaP cells(prostate carcinoma), MCF7 cells(breast carcinoma) and He La cells(cervical carcinoma) at various dosages and diverse time points. Cell viability and proliferation were estimated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Results: S. officinalis essential oil at doses of 100 μg/m L and 200 μg/m L induced a significant reduction of cell viability in MCF7, LNCa P and He La cell lines after a 48-hour incubation. the same cell lines also showed decreased cell viability when they were treated with a mixture of three major components of the essential oil, at doses of 100 μg/mL and 200 μg/mL, after a 48-hour incubation. Conclusions: these preliminary results could shed light on the formulation of new therapeutic agents with antiproliferative activity. thus supplementary investigations are fundamental to examine the molecular mechanisms of the anticancer effects of this species of Salvia in cancer cells and to achieve confirmation of its in vivo anticancer activity.

关键词： Antiproliferative activity Hormone-dependent cancers Essential oil Salvia officinalis

Oil charging history and pathways of the Ordovician carbonate reservoir in the tuoputai region,tarim Basin,NW China

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Petroleum Science 2017年第4期14卷 662-675页

作者： Rong-Hui Fang Mei-Jun Li Hai-tao Lü t.-G.Wang Yuan Yuan Yong-Li Liu Zhi-Yong Ni State Key Laboratory of Petroleum Resources and Prospecting College of GeosciencesChina University of PetroleumBeijing 102249China Exploration and Development Research Institute Northwest Oilfield Branch CorporationSINOPECUrumqi 830011XinjiangChina Research Institute of Shaanxi Yanchang Petroleum(Group)Co.Ltd Xi'an 710075ShaanxiChina

Geochemical analysis of 64 oils sampled from an Ordovician carbonate reservoir in the tuoputai region was undertaken to study the composition of molecular markers. All the oils have similar geochemical characteristics and belong to a single oil family. they are presumed to derive from the same source kitchen and have similar oil charging history. A histogram of homogenization temperatures(th) of aqueous inclusions in reservoir rocks shows a bimodal distribution pattern, indicating that the Ordovician reservoir has been charged twice. Coupling the measured th(°C) with the burial and geothermal histories reconstructed using 1D basin modeling, we relate the homogenization temperature to the relevant geological ages: i.e.,425–412 and 9–4 Ma, corresponding to the Middle to Late Silurian and the Miocene to Pliocene, respectively. the oil filling orientation and pathways are traced using molecular indicators related to alkyldibenzothiophenes and benzo[b]naphthothiophenes. the oil charging orientation is from south to north generally. It can be predicted that the Ordovician reservoirs were sourced from a kitchen located to the south of the tuoputai region, most probably between the Awati and Manjiaer Depressions. traps located in the southern side of the tuoputai region, along the oil charging pathways, should therefore be preferred oil exploration targets.

关键词： Oil population Oil charging events Fluid inclusion 1D numerical modeling Oil filling pathway

In-Flight Formation of Nano-Crystalline titanium Dioxide Powder in a Plasma Jet and Its Characterization

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Plasma Science and technology 2010年第4期12卷 426-432页

作者： P. V. ANANtHAPADMANABHAN M. VIJAY t. K. tHIYAGARAJAN K. P. SREEKUMAR V. SELVARAJAN Jiaguo YU Shengwei LIU Laser & Plasma technology Division Bhabha Atomic Research Centre Mumbai-400085 India Department of Physics Bharathiar University Coimbatore 641046 India State Key Laboratory of Advanced technology for Material Synthesis and Processing Wuhan University of technology Wuhan 430070 China

Nanocrystalline titanium dioxide powder was synthesized by in-flight oxidation of titanium dihydride （tiH2） powder in a thermal plasma jet. tiH2 powder was injected into the thermal plasma jet and allowed to react with oxygen injected downstream the jet. Characteriza- tion of the powder by various analytical tools indicated that the powder consisted of nano-sized titanium dioxide particles consisting predominantly of the anatase phase. It is suggested that the thermo-chemistry of the oxidation process contributes significantly to the formation of nano-sized titania. the large energy released during the oxidation process dissociates the tiO2 particles into tiO（g） and titanium vapour, which recombine downstream with oxygen and form nano particles of tiO2.

关键词： nanostructures titanium dioxide arc plasma synthesis reactive plasma pro- cessing surface properties

Assessment of Sensitization in AISI 304 Stainless Steel by Nonlinear Ultrasonic Method

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 545-552页

作者： Saju t.Abraham S.K.Albert C.R.Das N.Parvathavarthini B.Venkatraman R.S.Mini K.Balasubramaniam Quality Assurance Division Indira Gandhi Centre for Atomic Research Department of Mechanical Engineering Government Engineering College Department of Mechanical Engineering Indian Institute of Technology

A nonlinear ultrasonic technique has been developed to evaluate sensitization in type 304 stainless steel. In order to achieve diferent degree of sensitization（DOS）, specimens have been subjected to heat treatment at 675℃ at varying soaking time（0.5, 1.0, 2.0, 3.0 and 4.0 h）. Heat treated specimens were subjected to intergranular corrosion tests as per AStM standards A262 and G108. Sensitization in longer soaked material has been confirmed through ditch microstructures, cracks on the bend tested specimens and higher degree of sensitization. Nonlinear ultrasonic studies showed variation in the nonlinearity parameter with soaking time which also confirms sensitization. A good correlation was observed between the degree of sensitization measured by the electrochemical potentiokinetic reactivation test and the ultrasonic nonlinearity *** study clearly demonstrated that nonlinear ultrasonic technique can be used as a potential technique for non-destructive characterization of sensitization in austenitic stainless steel.

关键词： Austenitic stainless steel Degree of sensitization Intergranular corrosion Nonlinear ultrasonics

Nano-fried-eggs： Structural, optical, and magnetic characterization of physically prepared iron-silver nanoparticles

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Nano Research 2018年第11期11卷 6074-6085页

作者： Julien Ramade Nicolas troc Olivier Boisron Michel Pellarin Marie-Ange Lebault Emmanuel Cottancin Vitor t. A. Oiko Rafael Cabreira Gomes Varlei Rodrigues Matthias Hillenkamp Univ. Lyon Universitd Claude Bernard Lyon I CNRS UMR5306 Institut Lumiee Matiee t=-69622 Villeurbanne France Instituto de F[sica Gleb Wataghin UNICAMP CP 6165 13083-970 Campinas SP Brazil

the prospect of combining both magnetic and plasmonic properties in a single nanoparticle promises both valuable insights on the properties of such systems from a fundamental viewpoint and numerous possibilities for technological applications. However, the combination of two of the most prominent metallic candidates—iron and silver—has presented numerous experimental difficulties because their thermodynamic properties impede miscibility and even coalescence. Herein, we present the thorough characterization of physically prepared Fe50Ag50 nanoparticles embedded in carbon and silica matrices via electron microscopy, optical spectroscopy, magnetometry and synchrotron-based X-ray spectroscopy. Iron and silver segregate completely into structures resembling fried eggs, with a nearly spherical, crystallized silver part surrounded by an amorphous structure of iron carbide or oxide, depending on the environment of the particles. Consequently, the particles exhibit both plasmonic absorption corresponding to the silver nanospheres in an oxide environment and a reduced but measurable magnetic response. the suitability of such nanoparticles for technological applications is discussed from the viewpoint of their high chemical reactivity with their environment.

关键词： nanoalloy bimetallic nanoparticles iron silver FeAg optical spectroscopy magnetometry

Determination of Velocity and Radius of Supernova Remnant after 1000 yrs of Explosion

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International Journal of Astronomy and Astrophysics 2015年第2期5卷 125-132页

作者： Baha t. Chiad Lana t. Ali Abdhreda S. Hassani Department of Physics College of Science University of Baghdad Baghdad Iraq Department of Astronomy and Space College of Science University of Baghdad Baghdad Iraq Department of Astronomy and Space College of Science University of Baghdad Baghdad Iraq

Supernova explosions are described as very violent events which transfer a significant amount of energy to interstellar media and are responsible for a large variety of physical processes. this study does not discuss the actual explosion mechanisms but follows the behavior of the dynamical evolution of some selected type I and type II supernova remnant and particularly after a thousand years from their explosion and shows how the density of the medium affects the evolution and the lifetime of each remnant. By studying such behaviors, a simplified model has been proposed here for the velocity and radius of the remnant after thousand years of explosion that depends only on the density of the medium and age of the remnant. It has been found that all types of supernova remnants have similar behaviors after a thousand years from their explosion despite their origin formation. Moreover, it is demonstrated that, when those selected remnants have entered or will enter into their radiative phase, an idea on their physical properties will be obtained.

关键词： Supernova Supernova remnant Radiative Phase

Patterns of in-hospital mortality and bleeding complications following PCI for very elderly patients： insights from the Dartmouth Dynamic Registry

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Journal of Geriatric Cardiology 2018年第2期15卷 131-136页

作者： Shawn X Li Hannah I Chaudry Jiyong Lee theodore B Curran Vishesh Kumar Kendrew K Wong Bruce W Andrus James t DeVries Dartmouth Geisel School of Medicine Hanover NH USA Department of Internal Medicine Dartmouth-Hitcheock Medical Center Lebanon NH USA Section of Cardiovascular Medicine Dartmouth-Hitchcock Medical Center Lebanon NH USA

Background Very elderly patients （age 〉 85 years） are a rapidly increasing segment of the population. As a group, they experience high rates of in-hospital mortality and bleeding complications following percutaneous coronary intervention （PCI）. However, the relationship between bleeding and mortality in the very elderly is unknown. Methods Retrospective review was performed on 17,378 consecutive PCI procedures from 2000 to 2015 at Dartmouth-Hitchcock Medical Center. Incidence of bleeding during the index PCI admission （bleeding requiring transfusion, access site hematoma 〉 5 cm, pseudoaneurysm, and retroperitoneal bleed） and in-hospital mortality were reported for four age groups （〈 65 years, 65-74 years, 75-84 years, and ≥ 85 years）. the mortality of patients who suffered bleeding complications and those who did not was calculated and multivariate analysis was performed for in-hospital mortality. Lastly, known predictors of bleeding were compared between patients age 〈 85 years and age ≥85 years. Results Of 17,378 patients studied, 1019 （5.9%） experienced bleeding and 369 （2.1%） died in-hospital following PCI. Incidence of bleeding and in-hospital mortality increased monotonically with increasing age （mortality： 0.94%, 2.27%, 4.24% and 4.58%; bleeding： 3.96%, 6.62%, 10.68% and 13.99% for ages 〈 65, 65-4, 75-84 and ≥ 85 years, respectively）. On multivariate analysis, bleeding was associated with increased mortality for all age groups except patients age ≥85 years [odds ratio （95% CI）： age 〈 65 years, 3.65 （1.99-6.74）; age 65-74 years, 2.83 （1.62-4.94）; age 75-84 years, 3.86 （2.56-5.82）, age ≥ 85 years 1.39 （0.49-3.95）]. Conclusions Bleeding and mortality following PCI increase with increasing age. For the very elderly, despite high rates of bleeding, bleeding is no longer predictive of in-hospital mortality following PCI.

关键词： Complications In-hospital mortality Percutaneous coronary intervention the elderly

the Coolibility of Melt Pool in PWR Lower Head - Results of LIVE Experiments

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Journal of Energy and Power Engineering 2010年第3期4卷 15-21页

作者： X. Gaus-Liu A. Miassoedov t. Cron t. Wenz Karlsruhe Institute Of technology Campus North 76344 Eggenstein-Leopoldshafen Germany

the LIVE （Late In-Vessel Phase Experiments） test program investigates in-vessel melt pool behaviour and cooling strategies for in-vessel corium retention during severe accidents in light water reactors （LWR）. the main part of the LIVE facility is a 1：5 scaled semi-spherical lower head of a typical pressurized water reactor. Up to now, LIVE experiments have been performed in different initial external cooling conditions, melt volumes and internal heat generations. At present the well-known simulant material KNO3-NaNO3 in non-eutectic composition （80 mole% KNO3-20 mole% NaNO3） and in eutectic composition （50 mole% KNO3- 50 mole% NaNO3） is used in the live program. the 3D heat flux distribution through vessel wall, melt pool temperature, crust thickness and the pool melt composition can be measured or determined. Extensive results have been obtained concerning the melt pool thermal hydraulic behaviour in transient and in steady state conditions.

关键词： Core melt LWR in vessel corium retention PWR lower head

Vertebrate pesticide risk assessment by indigenous communities in New Zealand

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Integrative Zoology 2010年第1期5卷 37-43页

作者： Shaun C.OGILVIE James M.AtARIA James WAIWAI James DOHERtY Aroha MILLER James G.ROSS Charles t.EASON Ecology Department Lincoln UniversityLincolnCanterburyNew Zealand Landcare Research LincolnCanterburyNew Zealand Lake Waikaremoana Hapu Restoration trust TuaiNew Zealand tuhoe tuawhenua trust MuruparaNew Zealand

In New Zealand,the vertebrate pesticide sodium fluoroacetate(Compound 1080)is aerially applied in baits for control of the brush-tailed possum trichosurus vulpecula(Kerr,1792).Maori,the indigenous people of New Zealand,have raised concerns about 1080 impacts on culturally-important ***,we outline two steps taken to help Maori assess 1080 ***,field research was undertaken to determine if naturally-occurring plants utilized by a Maori community for food and medicine would take up 1080 from *** baits were placed at the base of individual plants of two species,pikopiko(Asplenium bulbiferum)and karamuramu(Coprosma robusta).Plants were sampled at various times up to 56 days,and samples were analyzed for 1080 *** 1080 was detected in any of the pikopiko samples,whereas 1080 was detected in karamuramu,at a maximum concentration of 5 ppb after seven days,and 2.5 ppb after 14 *** concentration decreased to 0 at 28 days,indicating that 1080 was not *** results of the present study suggest there is negligible risk of humans being poisoned by consum-ing plants that have taken up 1080 from *** allay community concerns that minute concentrations of 1080 might influence the medicinal properties of plants,it is suggested that a withholding period of 30 days after 1080 control operations could be ***,after further consultation we undertook a review of the scientific literature relating to 1080 impacts on additional non-target species of cultural importance to *** information was presented on an interactive foodweb database that allowed the collection and presentation of a large volume of complex information about 1080 in a holistic and pictorial *** database was presented to many Maori communities throughout New Zealand,and feedback was overwhelmingly *** database is likely to play a key role in informing these communities about 1080,and is seen as an important new tool to help these communities

关键词： 1080 indigenous communities Maori risk assessment sodium fluoroacetate