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Three-Dimensional Linear Instability Analysis of Thermocapillary Return Flow on a Porous Plane

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Chinese Physics Letters 2010年第2期27卷 165-168页

作者：赵思诚刘秋生 NGUYEN-THI Henri BILLIA bernard Key Laboratory of Microgravity Institute of Mechanics Chinese Academy of Sciences Beijing 100190 IM2NP UMR CNRS 6137 Université d'Aix-Marseille III 13397 Marseille Cedex 20 France

A three-dimensional linear instability analysis of thermocapillary convection in a fluid-porous double layer system, imposed by a horizontal temperature gradient, is performed. The basic motion of fluid is the surface-tension-driven return flow, and the movement of fluid in the porous layer is governed by Darcy＇s law. The slippery effect of velocity at the fluid-porous interface has been taken into account, and the influence of this velocity slippage on the instability characteristic of the system is emphasized. The new behavior of the thermocapillary convection instability has been found and discussed through the figures of the spectrum.

关键词： Fluid dynamics

Protein Complexes Implicated in RNA Editing in Plant Organelles

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Molecular Plant 2017年第10期10卷 1255-1257页

作者： bernard Gutmann santana Royan Ian small ARC Centre of Excellence in Plant Energy Biology School of Molecular Sciences The University of Western Australia Crawley WA 6009 Australia

Even after 30 years of active research, RNA editing in plant organelles remains an enigma. Why do most plants post- transcriptionally alter hundreds or thousands of nucleotides in organellar transcripts？ How do they achieve such an effective and targeted process？ What is known is that in almost all plants, RNA editing is essential for correct synthesis of the photosynthetic and respiratory machinery in mitochondria and chloroplasts. The sites to be edited are defined by a large class of sequence-specific RNA binding proteins： pentatricopeptide repeat （PPR） proteins （Barkan and small, 2014）. However, genetic and biochemical evidence has long suggested that other factors must be involved too. Two recent papers in Proceedings of the National Academy of sciences UsA provide exciting new evidence for protein complexes implicated in RNA editing using known mitochondrial or piastid PPR editing factors as bait in pull-down assays （Andres-Colás et al., 2017; Guillaumot et al., 2017）.

关键词： PENTATRICOPEPTIDE REPEAT PROTEINs MITOCHONDRIA PLAsTIDs

Production of Artificial Fog in the PAVIN Fog and Rain Platform: In search of Big Droplets Fog

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Atmospheric and Climate sciences 2024年第1期14卷 42-61页

作者： Pierre Duthon Mickaël Ferreira Fernandes sébastien Liandrat Cerema Reasearch Team STI 8-10 Rue Bernard Palissy Clermont-Ferrand France

In fog, visibility is reduced. This reduction in visibility is measured by the meteorological optical range (MOR), which is important for studying human perception and various sensors in foggy conditions. The Cerema PAVIN Fog & Rain platform is capable of producing calibrated fog in order to better analyses it and understand its consequences. The problem is that the droplets produced by the platform are not large enough to resemble real fog. This can have a major impact on measurements since the interaction between electromagnetic waves and fog depends on the wavelength and diameter of the droplets. To remedy this, Cerema is building a new platform with new equipment capable of generating fog. This study analyses different nozzles and associated usage parameters such as the type of water used and the pressure used. The aim is to select the best nozzle with the associated parameters for producing large-diameter droplets and therefore more realistic fog.

关键词： Fog Physical simulation Droplets size Distribution Meteorological Optical Range

Low-to-Moderate Alcohol Consumption May Be safe When Taking Methotrexate for Rheumatoid Arthritis or Psoriasis

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Open Journal of Rheumatology and Autoimmune Diseases 2012年第3期2卷 39-46页

作者： bernard s. Ng Houston Veterans Affairs HsR & D Center of Excellence Michael E DeBakey Veterans Affairs Medical Center Houston USA

It is unclear if consumption of small to moderate amounts of alcohol is safe while taking methotrexate. We set out to determine whether there is an association between liver enzyme abnormalities and alcohol consumption in subjects taking methotrexate. The study sample was identified from the database of the south Central Veteran Affairs Healthcare Network, consisting of 10 hospitals in Texas, Oklahoma, Mississippi and Louisiana. From a cohort of 2443 eligible Veterans with rheumatoid arthritis and/or psoriasis taking methotrexate from 10/1/2007 to 9/30/2009, 120 cases with abnormal liver-enzyme elevation were randomly selected to compare with 120 controls. Data were collected from mailed survey forms that inquired about alcohol consumption habits, physicians’ advice on alcohol, and methotrexate compliance. There was no significant difference in the number of non-drinkers and low-to-moderate alcohol drinkers between cases and controls (p = 0.217). Few persons identified themselves as heavy drinkers. Our data suggest that it is likely safe for patients with rheumatoid arthritis and psoriasis to consume low-to-moderate amounts of alcohol while taking methotrexate. However, alternative methods to improve capturing alcohol consumption in heavy drinkers are needed for more comprehensive results.

关键词： Methotrexate Alcohol Liver Enzymes Rheumatoid Arthritis Psoriasis

Dietary treatment of colic caused by excess gas in infants:Biochemical evidence

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World Journal of Gastroenterology 2011年第16期17卷 2104-2108页

作者： Dámaso Infante Oscar segarra bernard Le Luyer Unit of Gastroenterology Hepatology and NutritionChildren's Hospital Vall d'HebronAutonomous University Medical Director UP International I.C.C Route de Pré-Bois

AIM:To evaluate the impact of feeding colicky infants with an adapted formula on the hydrogen breath test and clinical ***:Hydrogen expiration was measured by sC MicroLyzer gas chromatography at inclusion and 15 d after treatment with an adapted low-lactose formula in 20 colicky ***:All babies were symptomatic:85% with excess gas,75% with abnormal feeding pattern,and 85% with excessive *** hydrogen breath test at inclusion was abnormal:35 ± 3.1 *** 15 d feeding with an adapted low-lactose formula,crying and flatulence decreased in 85% of patients (P s in whom no decrease of gas was reported,crying was still reduced (P s improved in 50% of infants when it was initially considered as ***,the hydrogen breath test decreased significantly (10 ± 2.5 ppm,P sION:This study showed an association between clinical improvement and evidence of decreased levels of hydrogen when the infants were fed with a specially designed,low-lactose formula.

关键词： Infants Colic Lactose Hydrogen breath test

Mechanisms of electrochemical magnesium(de)alloying of Mg-sn and Mg-Pb polymorphs

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Journal of Magnesium and Alloys 2022年第6期10卷 1609-1616页

作者： Clément Pechberty Antoine Klein bernard Fraisse Lorenzo stievano Romain Berthelot ICGM CNRSUniv.MontpellierENSCMMontpellierFrance Rs2E CNRSHub de l’EnergieAmiensFrance

Different polymorphs of Mg-sn and Mg-Pb intermetallic compounds were prepared by high-energy mechanical alloying and then investigated as active material in magnesium batteries. Beside thermodynamically stable Mg_(2)sn and Mg_(2)Pb crystallizing in the anti-fluorite structure, other polymorphs Mg_(~2)sn and Mg_(~2)Pb were prepared by increasing the ball-milling time. The first dealloying process is almost complete only for the cubic polymorphs, then similar capacities are observed during the subsequent alloying and dealloying *** to operando X-ray diffraction, the electrochemical mechanism is revealed and shows that the cubic polymorphs Mg_(2)sn and Mg_(2)Pb tend to preferentially form during the alloying whatever the pristine intermetallic. Weak traces of Mg_(~2)sn and Mg_(~2)Pb are observed during the alloying, suggesting that these polymorphs act as a by-product and/or an intermediate phases of the electrochemical process. Finally, the compatibility of cubic Mg_(2)sn and Mg_(2)Pb with Mg(TFsI)_(2)-based electrolyte is confirmed in full cell vs. a positive electrode based on the Chevrel phase Mo6s8, although limited performance is achieved. This fundamental work provides new insights in the behavior of alloy-type negative electrodes for magnesium-ion batteries.

关键词： Magnesium batteries Alloy electrode Mechanochemistry Operando X-ray diffraction

UNUsUAL CRYsTALLIZATION AND MELTING PROCEssEs OF AN OPTICALLY ACTIVE POLYOLEFIN:IsOTACTIC POLY((s)-4-METHYL-HEXENE-1)

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Chinese Journal of Polymer science 2005年第2期23卷 165-170页

作者： Annamaria Buono JrjengRuan AnnetteThierry Peter Neuenschwander bernard Lotz Institut Charles sadron and Dipartimento di Chimica Universita di Napoli Federico ⅡVia Cynthia 5NapoliItalyInstitut Charles Sadron(CNRS-ULP)6Rue Boussingault67083 StrasbourgFranceInstitut Charles Sadron(CNRS-ULP)6Rue Boussingault67083 StrasbourgFranceInstitute for PolymersETH ZentrumCNB E 93.2Universitaetstrasse 6CH-8092 ZurichSwitzerlandInstitut Charles Sadron(CNRS-ULP)6Rue Boussingault67083 StrasbourgFrance

Polyolefins that bear a chiral side chain(typically an isobutyl group)experience a so-called macromolecularamplification of chirality:the chiral side-chain induces a slight preference for either tg or tg(?) main chain ***slight conformational bias is amplified cooperatively along the chain,and results in preferred chirality of the main chainhelical *** a result,these polymers display a liquid-crystal(LC)phase both in solution and,in the melt as atransient phase on the way to *** existence of two processes(melt-LC and LC-crystal transitions)results inunconventional behaviors that were first analyzed by Pino and collaborators back in *** polymers also offer a meansto test the structural consequences of recently introduced crystallization *** schemes postulate the formation of atransient liquid-crystal phase as a general scheme for polymer crystallization.

关键词： Liquid crystalline polyolefins Crystallization Melting Amplification of chirality.

scientific geodata infrastructures: challenges, approaches and directions

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International Journal of Digital Earth 2014年第7期7卷 613-633页

作者： Lars bernard stephan Mas Matthias Muller Christin Henzen Johannes Brauner Department of Geosciences Faculty of Environmental SciencesTechnische Universitat DresdenDresdenGermany

Based on various experiences in developing Geodata Infrastructures(GDIs)for scientific applications,this article proposes the concept of a scientific GDI that can be used by scientists in environmental and earth sciences to share and disseminate their research results and related analysis *** GDI is understood as an approach to tackle the science case in Digital Earth and to further enhance e-science for environmental *** scientific GDI to support the research community in efficiently exchanging data and methods related to the various scientific disciplines forming the basis of environmental studies poses numerous challenges on today’s GDI *** paper summarizes requirements and recommendations on the publication of scientific geospatial data and on functionalities to be provided in scientific *** practices and open issues for governance and policies of a scientific GDI are discussed and are concluded by deriving a research agenda for the next decade.

关键词： scientific geodata infrastructure sharing environmental models geospatial cyberinfrastructure e-science spatial data infrastructure

Response of C and N cycles to N fertilization in sphagnum and Molinia-dominated peat mesocosms

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Journal of Environmental sciences 2019年第3期31卷 264-272页

作者： Fabien Leroy sébastien Gogo Christophe Guimbaud André-Jean Francez Renata Zocatelli Christian Défarge Léonard bernard-Jannin Zhen Hu Fatima Laggoun-Défarge University of Orleans ISTO CNRs ISTO BRGM ISTO University of Orleans LPC2E CNRs LPC2E UMR CNRs 6553 ECOBIO University of Rennes 1 University of Orleans Cellule R&D CETRAHE school of Environmental science and Engineering Shandong University

Plant communities play an important role in the C-sink function of peatlands. However,global change and local perturbations are expected to modify peatland plant communities,leading to a shift from sphagnum mosses to vascular plants. Most studies have focused on the direct effects of modification in plant communities or of global change(such as climate warming, N fertilization) in peatlands without considering interactions between these disturbances that may alter peatlands' C function. We set up a mesocosm experiment to investigate how Greenhouse Gas(CO_2, CH_4, N_2O) fluxes, and dissolved organic carbon(DOC)and total dissolved N(TN) contents are affected by a shift from sphagnum mosses to Molinia caerulea dominated peatlands combined with N fertilization. Increasing N deposition did not alter the C fluxes(CO_2 exchanges, CH_4 emissions) or DOC content. The lack of N effect on the C cycle seems due to the capacity of sphagnum to efficiently immobilize N. Nevertheless, N supply increased the N_2O emissions, which were also controlled by the plant communities with the presence of Molinia caerulea reducing N_2O emissions in the sphagnum mesocosms. Our study highlights the role of the vegetation composition on the C and N fluxes in peatlands and their responses to the N deposition. Future research should now consider the climate change in interaction to plants community modifications due to their controls of peatland sensitivity to environmental conditions.

关键词： CO2 and CH4 N2O Peatland Plant community composition sphagnum moss Graminoid