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Early Cambrian Mollusc Watsonella crosbyi:A Potential GSSP Index Fossil for the Base of the Cambrian Stage 2

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 309-319页

作者： LI Guoxiang ZhAO Xin alexander GUBANOV ZhU Maoyan NA Lin State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontologythe Chinese Academy of Sciences Nanjing 210008 China CASP Department of Earth Sciences University of Cambridge Cambridge UK

The mollusc Watsonella crosbyi was studied on the basis of material from the lower Cambrian Dahai Member of the Zhujiaqing Formation in eastern Yunnan, China and the Pestrotsvet Formation of the Aldan River region in the Siberian Platform. This fossil had been excessively described under different names in the literature, such as heraultia varensalensis Cobboid, 1935, h. sibirica Missarzhevsky, 1974, heraultipegma yunnanensis he and Yang, 1982, h. yannanese he and Yang,1982, Watsonella yunnanensis, W. crosbyi Grabau, 1900, etc. Taxonomic revision shows that other species are junior synonyms of W. crosbyi. Analysis of functional morphology implies that W. crosbyi may be rather a heicionelloid than a rostroconch since its univalved conch is untorted endogastric and lacks a rostrum and a true internal pegma. Replicas of the original microstrnctures preserved on the surfaces of phosphatic internal moulds confirm that the shell consists of two layers. The inner layer is lamello-fibrillar, and the outer layer is spherulitic prismatic. The widespread geographical occurrences in both siliciclastic and carbonate rocks of the late Terreneuvian indicate that W. crosbyi is an important index fossil for global correlations and subdivision of the Cambrian Series I （Terreneuvian）.The first appearance datum （FAD） of W. crosbyi is suggested to be a potential GSSP （Global Boundary Stratotype Section and Point） candidate marker for defining the base of the Cambrian Stage 2.

关键词： mollusc Watsonella crosbyi microstructure Terreneuvian Cambrian Stage 2 South China Siberian Platform

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Dynamic carbon surface chemistry: Revealing the role of carbon in electrolytic water oxidation

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Journal of Energy Chemistry 2020年第8期29卷 155-159,I0006页

作者： Yuxiao Ding Qingqing Gu alexander Klyushin Xing huang Sakeb h.Choudhury Ioannis Spanos Feihong Song Rik Mom Pascal Dungen Anna K.Mechler Robert Schlogl Saskia heumann Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36Mtilheim an der Ruhr 45470Germany Fritz-haber-Institut der Max-Planck Gesellschaft Faradayweg 4-6Berlin 14195Germany Research Group Catalysis for Energy Helmholtz-Zentrum Berlin fur Materialien und Energie GmbHAlbert-Einstein-Strasse 1512489 BerlinGermany

Carbon materials have been widely used as electrodes, but the mechanistic roles are still not clear due to the complexity of the carbon surface chemistry. herein we clarify that intrinsic material properties of carbon have to be activated by extrinsic factors. Pure carbon has no catalytic activity when used as electrode for electrocatalytic water oxidation. The evolution of oxygen functional groups on the carbon surface with increasing potential and the subsequent formation of real active sites with iron impurities from the electrolyte have been confirmed. These in-situ formed active sites protect the carbon from deep oxidation. This unprecedented finding not only provides insight into the dynamic evolution of carbon electrode surface chemistry and raises awar.ness of the need for detailed surface analysis under operando conditions, but also suggests a direction for the development of scalable and high-performance carbonbased electrode systems for various electrochemical applications.

关键词： Carbon chemistry Carbon catalysis Carbon electrode Water splitting Iron impurity

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Degassing of primordial hydrogen and helium as the major energy source for internal terrestrial processes

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Geoscience Frontiers 2012年第6期3卷 911-921页

作者： Arie Lev Gilat alexander Vol Geological Survey of Israel(Ret.) 6/2 Shoshan Tsahor St..Modi'in 71705.Israel Oshadi Drug Administration Ltd P.O.Box 2042.Rehovot 76120Israel

Examples of the mightiest energy releases by great earthquakes and volcanic eruptions and hypotheses providing explanations for them are analyzed along with the results of some recently pub- lished researches and visualizations. The emerging conclusions are that the mechanism of the strong earthquake is a chemical explosion; that volcanic eruption is a special type of earthquake wherein the hypocenter rises to the earth-surface; and that there is an association between the seismic-volcanic processes and mantle ＂fluids＂ and the lack of energy for mantle plumes. A conceptual system of hypoth- eses is put forwar. to explain the conservation of energy during Earth＇s accretion, its quasi-stable release by primordial h- and he-degassing and of the crucial role of the energy of degassing-eomprising- reactions in endogenic processes. Specific mechanisms and chemical processes are proposed for the gas-liquid mantle plumes melting through the solid mantle using heat-energy released in reactions of their metamorphic and chemical transformation under gradual decrease of pressure and temperature; volcanic gases are put forwar. as energy carriers. 3he performance as a unique measuring transformer correlative to the internal heat flow was used for calculation of energy release by degassing; it equals to 5.12 × 1020 J/yr, an amount of energy five-fold greater than the entire energy loss involved in earthquake and volcanic activity. The hypotheses proposed are objectively testable.

关键词： Earthquakes Volcanism Energy-source hydrogen helium Degassing

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histone deacetylase inhibitor MS-275 alone or combined with bortezomib or sorafenib exhibits strong antiproliferative action in human cholangiocarcinoma cells

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World Journal of Gastroenterology 2007年第33期13卷 4458-4466页

作者： Viola Baradari Michael hpfner alexander.h.ether Detlef Schuppan hans Scherübl Institute of Physiology Charité-Universit?tsmedizin Berlin CampusBenjamin Franklin Berlin Germany Division of Gastroenterology Beth Israel Deaconess Medical Center Harvard Medical School Boston United States Klinik für Gastroenterologie und Gastrointestinale Onkologie Klinikum Am Urban Vivantes Netzwerk fürGesundheit Berlin Germany

AIM: To investigate the antiproliferative effect of the histone deacetylase (hDAC) inhibitor MS-275 on cholangiocarcinoma cells alone and in combination with conventional cytostatic drugs (gemcitabine or doxorubicin) or the novel anticancer agents sorafenib or bortezomib. METhODS: Two human bile duct adenocarcinoma cell lines (EGI-1 and TFK-1) were studied. Crystal violet staining was used for detection of cell number changes. Cytotoxicity was determined by measuring the release of the cytoplasmic enzyme lactate dehydrogenase (LDh). Apoptosis was determined by measuring the enzyme activity of caspase-3. Cell cycle status reflected by the DNA content was detected by flow ***: MS-275 treatment potently inhibited the proliferation of EGI-1 and TFK-1 cholangiocarcinoma cells by inducing apoptosis and cell cycle arrest. MS-275-induced apoptosis was characterized by activation of caspase-3, up-regulation of Bax and down-regulation of Bcl-2. Cell cycle was predominantly arrested at the G1/S checkpoint, which was associated with induction of the cyclin-dependent kinase inhibitor p21Waf/CIP1. Furthermore, additive anti-neoplastic effects were observed when MS-275 treatment was combined with gemcitabine or doxorubicin, while combination with the multi-kinase inhibitor sorafenib or the proteasome inhibitor bortezomib resulted in overadditive anti-neoplastic ***: The growth of human cholangiocarcinoma cells can be potently inhibited by MS-275 alone or in combination with conventional cytostatic drugs or new, targeted anticancer agents.

关键词： Apoptosis Cholangiocarcinoma Bortezomib Combination treatment histone deacetylase inhibitor MS-275 Proteasome inhibitor Sorafenib

hAEMOPOIETIC PROGENITOR CELLS MEASURED BY LIMITING DILUTION IN MICROWELL CULTURE

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Science China Chemistry 1985年第10期28卷 1070-1078页

作者：万景华,alexander A.MORLEY Institute of haematology Chinese Academy of Medical Sciences Tianjin Department of haematology Flinders Medial Centre Adelaide. Australia

Microwell culture assays, termed the "negative" well technique and the "positive" well technique have been used to measure the concentration of murine haemopoietic progenitor cells （hPC） by limiting dilution. Using morphologic examination and3h-TdR uptake, the number of hPC of Balb/c mice per 10～5 bone marrow cells was 33 and 31 respectively. The linear relation between the number of harvested cells and input ceils seen on the 4th and 7th days of culture reflected the growth of hPC in microwells

关键词： well hPC hAEMOPOIETIC PROGENITOR CELLS MEASURED BY LIMITING DILUTION IN MICROWELL CULTURE

Pyrrolidine dithiocarbamate reduces ischemia-reperfusion injury of the small intestine

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World Journal of Gastroenterology 2005年第46期11卷 7308-7313页

作者： Ismail h Mallick Wen-Xuan Yang Marc C Winslet alexander M Seifalian GI and hepatobiliary Research Unit University Department of Surgery Royal Free and University College Medical School University College London LondonUnited Kingdom Department of Surgery Royal Free Hospital Hampstead NHS Trust London United Kingdom

AIM： To evaluate whether pyrrolidine dithiocarbamate （PDTC）, an enhancer of hO production, attenuates intestinal IR injury. METhODS： Eighteen male rats were randomly allocated into three groups：（a） sham; （b） IR, consisting of 30 min of intestinal ischemia, followed by 2-h period of reperfusion; and （c） PDTC treatment before IR. Intestinal microvascular perfusion （IMP） was monitored continuously by laser Doppler flowmetry. At the end of the reperfusion, serum samples for lactate dehydrogenase （LDh） levels and biopsies of ileum were obtained. hO activity in the ileum was assessed at the end of the reperfusion period. RESULTS： At the end of the reperfusion in the IR group, IMP recovered partially to 42.5% of baseline （P〈0.05 vs sham）, whereas PDTC improved IMP to 67.3% of baseline （P〈0.01 vs IR）. There was a twofold increase in hO activity in PDTC group （2 062.66±106.11） as compared to IR （842.3±85.12）（P〈0.001）. LDh was significantly reduced （P〈0.001） in PDTC group （585.6±102.4） as compared to IR group （1 973.8±306.5）. histological examination showed that the ileal mucosa was significantly less injured in PDTC group as compared with IR group. CONCLUSION： Our study demonstrates that PDTC improves the IMP and attenuates IR injury of the intestine possibly via hO production. Additional studies are war.anted to evaluate the clinical efficacy of PDTC in the prevention of IR injury of the small intestine.

关键词： Intestine Ischemia-reperfusion injury heme oxygenase Pyrrolidine

Ultra-subwavelength phase-sensitive Fano-imaging of localized photonic modes

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Light(Science & Applications) 2015年第1期4卷 223-230页

作者： Niccolo Caselli Francesca Intonti Federico La China Francesco Riboli Annamaria Gerardino Wei Bao alexander Weber Bargioni Lianhe Li Edmund h Linfield Francesco Pagliano Andrea Fiore Massimo Gurioli European Laboratory for Nonlinear Spectroscopy via Nello Carrara 150019Sesto Fiorentino(FI)Italy Department of Physics University of Florencevia Sansone 150019 Sesto Fiorentino(FI)Italy Department of Physics University of Trentovia Sommarive 1438123Povo(TN)Italy Institute of Photonics and Nanotechnology CNR00156 RomaItaly Molecular Foundry Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA School of Electronic and Electrical Engineering University of LeedsLeeds LS29JTUK COBRA Research Institute Eindhoven University of Technology5600 MB EindhovenThe Netherlands

Photonic and plasmonic devices rely on nanoscale control of the local density of optical states(LDOS)in dielectric and metallic *** tremendous progress in designing and tailoring the electric LDOS of nano-resonators requires an investigation tool that is able to access the detailed features of the optical localized resonant modes with deep-subwavelength spatial *** scenario has motivated the development of different nanoscale imaging ***,we prove that a technique involving the combination of scanning near-field optical microscopy with resonant scattering spectroscopy enables imaging the electric LDOS in nano-resonators with outstanding spatial resolution(λ/19)by means of a pure optical method based on light *** this technique,we investigate the properties of photonic crystal nanocavities,demonstrating that the resonant modes appear as characteristic Fano line shapes,which arise from ***,by monitoring the spatial variation of the Fano line shape,we locally measure the phase modulation of the resonant modes without the need of external heterodyne *** novel,deep-subwavelength imaging method allows us to access both the intensity and the phase modulation of localized electric ***,this technique could be implemented on any type of platform,being particularly appealing for those based on non-optically active material,such as silicon,glass,polymers,or metals.

关键词： nanocavity nanophotonics near-field phase retrieval resonant-scattering

A Unified CFD Based Approach to a Variety of Condensation Processes in a Viscous Turbulent Wet Steam Flow

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International Journal of Modern Nonlinear Theory and Application 2017年第3期6卷 85-97页

作者： alexander S. Liberson Stephen h. hesler Department of Mechanical Engineering Rochester Institute of Technology Rochester NY USA Electric Power Research Institute (EPRI) Charlotte NC USA

A family of quasi linear mathematical models is presented and calculations made for viscous turbulent wet steam flow with a variety of condensation phenomena. These models can be applied to the analysis of equilibrium condensation, homogeneous (spontaneous) condensation, heterogeneous condensation on extraneous particles, and condensation of charged dispersed phase moving in an electrostatic field. The unified model is represented by coupled systems of gas dynamic equations for viscous turbulent two-phase flow, kinetic and electro-kinetic equations tracing out combined processes of size and charge growth, and electromagnetic field equations described an electric field with an account of self-induced in-part by a moving electrical cluster. The numerical procedure is time marching, monotone, implicit, of second order accuracy by space and time coordinates, and exhibits high resolution shock capturing ability. Viscous flow field calculations made with this procedure reveal significant influence on condensation by the shear boundary layers and wakes. Distributions of cooling rate, droplet radius and parameters of the bulk flow are predicted. Verification of the codes against known experimental data is presented.

关键词： Non-Equilibrium Condensation Turbulent Kinetic Equations TVD Scheme

Exercise Catheterization for hemodynamic Evaluation of Adults with Coarctation of the Aorta

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Congenital heart Disease 2022年第6期17卷 605-615页

作者： Irene Martin de Miguel C.Charles Jain alexander C.Egbe Jason h.Anderson heidi M.Connolly William R.Miranda Department of Cardiovascular Medicine Mayo ClinicRochesterMinnesotaUSA Department of Pediatric and Adolescent Medicine Division of Pediatric CardiologyMayo ClinicRochesterMinnesotaUSA

Background: Coarctation of the aorta (CoA) is associated with a generalized arteriopathy and long-term complicationsdespite repair. Data on invasive exercise hemodynamics in this population are lacking. Accordingly, wereviewed adults with CoA undergoing exercise catheterization to assess 1. hemodynamic profile;2. feasibilityfor assessment of CoA severity. Methods: Twenty patients undergoing exercise cardiac catheterization (12 armadduction and 8 supine cycle ergometry) at a quaternary care center between 2004 and 2021 were identified. Restingand exercise hemodynamic data were abstracted from the procedure logs. Results: Mean age was 43.6 ±12.0 years. Eleven patients (55%) had resting pulmonary arterial wedge pressure (PAWP) >15 mmhg;amongthose undergoing arterial catheterization, left ventricular end-diastolic pressure was >15 mmhg in 63%. Elevenpatients (55%) had pulmonary hypertension: 7 (35%) combined and 4 (20%) isolated post-capillary. At peak exercise,ΔPAWP/Δcardiac output (CO) ≥2 and Δmean pulmonary artery pressure/ΔCO ≥3 mmhg/l/min were foundin 7 (78%) and 6 (67%) patients, respectively;the composite of exercise PAWP ≥25 mmhg or ΔPAWP/ΔCO>2 was seen in 12 (86%). CoA peak-to-peak gradients at baseline (n = 14) and during exercise (n = 9) were 12(3–16) and 16 mmhg (9–28), respectively. Only 2 patients had an increase in CoA gradient to >20 mmhg withexercise. Conclusions: Diastolic dysfunction and pulmonary hypertension were highly prevalent, with exerciseunmasking abnormal diastolic and pulmonary vascular reserve in some individuals. Most patients failed to showsignificant increases in CoA peak-to-peak gradients with exercise. Further studies are war.anted to establish thebest diagnostic method for CoA severity assessment.

关键词： Coarctation of the aorta exercise heart catheterization diastolic dysfunction hypertension