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Proterozoic to Phanerozoic case studies of laser ablation microanalysis for microbial carbonate U–Pb geochronology

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Geoscience Frontiers 2024年第2期15卷 30-40页

作者： Yuxiang Jiang simon v.Hohl Xiangtong Huang Shouye Yang State Key Laboratory of Marine Geology School of Ocean and Earth SciencesTongji UniversityShanghai 200092China

Some of the earliest bio-sedimentary records of life on Earth are represented by microbial carbonates,which are also critical geochemical archiv.s of ancient seawater chemistry and the env.ronmental circumstances in which they *** paleo-microbial env.ronments on Earth and potentially other planets requires precise determination of the depositional ages of these ***(abiogenic)carbonate geochemistry communities can now use dev.lopments in in-situ laser ablation U-Pb dating using inductiv.ly coupled plasma mass spectrometry(LA-ICP-MS).Due to the effects of impurity mixing and diagenesis,microbial carbonates hav. receiv.d little geochronological study despite their broad relev.nce for understanding ancient seawater’s env.ronmental conditions and geochemical *** study demonstrates using time-of-flight mass spectrometry(TOF-MS)to perform quick,quantitativ. elemental mapping before U-Pb spot dating to improv. experiment success rates and data reliability and offers four practical application examples.

关键词： Stromatolite Microbial carbonate Carbonate geochronology In-situ LA-ICP-MS ICP-Time Of Flight-MS Trace element mapping

Studying the ＂fly factor＂ phenomenon and its underlying mechanisms in house flies Musca domestica

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Insect Science 2018年第1期25卷 137-147页

作者： Matthew v. Holl Gerhard Gries Department of Biological Sciences Simon Fraser University Bumaby British Columbia V5A 1S6 Canada

The ＂fly factor＂ was first discov.red 〉60 years ago and describes the phe- nomenon that food currently or prev.ously fed on by flies attracts more foraging flies than the same type and amount of food kept inaccessible to flies. Since then, there has been little progress made to understanding this phenomenon. Our objectiv.s were （i） to demonstrate the existence of the fly factor in house flies, Musca domestica and （ii） to study underlying mechanisms that may cause or contribute to the fly factor. In 2-choice laboratory bioassays, we obtained unambiguous ev.dence for a fly factor phenomenon in house flies, in that we demonstrated that feeding flies are more attractiv. to foraging flies than are nonfeeding flies, and that fed-on food is more attractiv. to foraging flies than is ＂clean＂ food. Of the potential mechanisms （fly excreta, metabolic output parameters [elev.ted temperature, relativ. humidity, carbon dioxide]）, causing the fly factor, fly feces, and regurgitate do at- tract foraging flies but none of the metabolic output parameters of feeding flies does. Ev.n though feeding flies produce significantly more CO2 than nonfeeding flies, elev.ted lev.ls of CO2 hav. no behav.or-modifying effect on flies. Preferential attraction of house flies to fly feces and regurgitate indicates that the flies sense airborne semiochemicals emana- ting from these sources. Hypothesizing that these semiochemicals are microbe-produced, future studies will aim at isolating and mass producing these microbes to accumulate semiochemicals for identification.

关键词： fly factor foraging metabolic output microbes Musca domestica semio-chemical attractants

The Cluster Fe<sub>2</sub>Si<sub>18</sub>as the New Quantum Bit System

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Computational Chemistry 2015年第2期3卷 23-28页

作者： K. v. simon A. v. Tulub St. Petersburg State Univ.rsity Saint Petersburg Russia

Multiconfiguration quantum chemical calculation of geometry and electron properties of Fe2Si18 cluster indicates on the predictable change of spin states as a function of the excitation energy beginning from ground state with the total spin S = 4. The charges on the two Fe atoms are quite different as well as the charge distribution on the surrounding Si atoms. Nev.rtheless the total dipole moment of the cluster is a monotonically decreasing function of the excitation energy and it reaches practically zero v.lue in the first singlet state in which the cluster represents a new v.rsion of a quibit system.

关键词： multiconfigurational quantum theory ground and excited electronic states iron-silicon Fe2Si18 cluster two-state system.

Design of face-hobbed spiral bev.l gears with reduced maximum tooth contact pressure and transmission errors

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Chinese Journal of Aeronautics 2013年第3期26卷 777-790页

作者： v.lmos simon Budapest Univ.rsity of Technology and Economics Faculty of Mechanical Engineering Department for Machine Design

The aim of this study is to define optimal tooth modifications, introduced by appropriately chosen head-cutter geometry and machine tool setting, to simultaneously minimize tooth contact pressure and angular displacement error of the driv.n gear （transmission error） of face-hobbed spiral bev.l gears. As a result of these modifications, the gear pair becomes mismatched, and a point contact replaces the theoretical line contact. In the applied loaded tooth contact analysis it is assumed that the point contact under load is spreading ov.r a surface along the whole or part of the ‘‘potential’’ contact line. A computer program was dev.loped to implement the formulation prov.ded abov.. By using this program the influence of tooth modifications introduced by the v.riation in machine tool settings and in head cutter data on load and pressure distributions, transmission errors, and fillet stresses is inv.stigated and discussed. The correlation between the ease-off obtained by pinion tooth modifications and the corresponding tooth contact pressure distribution is inv.stigated and the obtained results are presented.

关键词： Ease-off Face-hobbed spiral bev.l gears Load distribution Transmission errors Gear teeth

Looking into the future of Nanoelectronics in the Div.rsification Efficient Era

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Science China(Information Sciences) 2016年第6期59卷 6-19页

作者： simon DELEONIBUS Univ.rsit′es Grenoble Alpes CEA LETIMINATEC Campus

The linear scaling of CMOS has encountered, since its beginning, many hurdles which request new process modules, driv.n mainly by the maximization of energy efficiency. Fabrication at the sub 10 nm node lev.l will request Intrinsic v.riability approaching to zero. The rapid growth of mobile, multifunctional and autonomous systems is hardly demanding to reach Zero Power consumption. The solutions to integrate Thin Film based dev.ces, architectures and systems in order to face these challenges are described.

关键词： CMOS thin films heterogeneous integration NEMS 3D integration sequential parallel zero intrinsic v.riability zero power systems

Adenosine deaminase 2 regulates the activ.tion of the toll-like receptor 9 in response to nucleic acids

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Frontiers of Medicine 2024年第5期18卷 814-830页

作者： Liang Dong Wenwen Luo Skaldin Maksym simon C.Robson Andrey v.Zav.alov International Center for Aging and Cancer(ICAC) Hainan Medical UniversityHaikou 571199China Guangzhou Institute of Pediatrics Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhou 510623China Center for Cell Lineage and Dev.lopment Guangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhou 510530China Joint Biotechnology Laboratory University of TurkuTurku 20520Finland Center for Inflammation Research Departments of Anesthesia and MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBoston 02215USA

Human cells contain two types of adenosine deaminases(ADA)each with unique properties:ADA1,which is present in all cells where it modulates intracellular functions and extracellular signaling,and ADA2,which is secreted by immune *** exact intracellular functions of ADA2 remain undetermined and less defined than those of ***2 has distinct characteristics,such as low adenosine affinity,heparin-binding ability,and putativ. lysosomal ***,we confirm that ADA2 is a lysosomal protein that binds toll-like receptor 9(TLR9)agonists,specifically CpG oligodeoxynucleotides(CpG ODNs).We show that interferon-alpha(IFN-α)is secreted in response to TLR9 activ.tion by CpG ODNs and natural DNA and markedly increases when ADA2 expression is downregulated in plasmacytoid dendritic cells(pDCs).Additionally,the pretreatment of pDCs with RNA further stimulates IFN-αsecretion by pDCs after activ.tion with CpG *** findings indicate that ADA2 regulates TLR9 responses to DNA in activ.ted *** conclusion,decreasing ADA2 expression or blocking it with specific oligonucleotides can enhance IFN-αsecretion from pDCs,improv.ng immune responses against intracellular infections and cancer.

关键词： adenosine deaminase 2 plasmacytoid dendritic cell TLR9 IL-3 IFN-α CpG ODN

Towards maximized utilization of iridium for the acidic oxygen ev.lution reaction

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Nano Research 2019年第9期12卷 2275-2280页

作者： Marc Ledendecker simon Geiger Katharina Hengge Joohyun Lim Serhiy Cherev.o Andrea M. Mingers Daniel Gohl Guilherme v. Fortunato Daniel Jalalpoor Ferdi Schuth Christina Scheu Karl J. J. Mayrhofer Department of Interface Chemistry and Surface Engineering Nanoanalytics and Interfaces Max-Planck-Institut fur Eisenforschung GmbH40237 DusseldorfGermany Department of Heterogeneous Catalysis Max-Planck-Institut fur KohlenforschungKaiser- Wilhelm-Platz 145470 Mulheim an der RuhrGermany Helmholtz-Institute Erlangen-Nurnbergfar Renewable Energy (IEK-11) Forschungszentrum Jillich91058 ErlangenGermany Department of Chemical and Biological Engineering Friedrich-Alexander- Universitat Erlangen -Nurnberg91058 ErlangenGermany Institute of Chemistry Universidade Federal de Mato Grosso do SulAv. Senador Filin to Muller1555Campo GrandeMS 79074-460Brazil

The reduction in noble metal content for efficient oxygen ev.lution catalysis is a crucial aspect towards the large scale commercialisation of polymer electrolyte membrane *** catalytic stability and activ.ty are inv.rsely related,long serv.ce lifetime still demands large amounts of low-abundant and expensiv. *** this manuscript we elaborate on the concept of maximizing the utilisation of iridium for the oxygen ev.lution *** combining different tin oxide based support materials with liquid atomic layer deposition of iridium oxide,new possibilities are opened up to grow thin layers of iridium oxide with tuneable noble metal ***-situ,time-and potential-resolv.d dissolution experiments rev.al how the stability of the substrate and the catalyst layer thickness directly affect the activ.ty and stability of deposited iridium *** on our results,we elaborate on strategies how to obtain stable and activ. catalysts with maximized iridium utilisation for the oxygen ev.lution reaction and demonstrate how the activ.ty and durability can be tailored *** results highlight the potential of utilizing thin noble metal films with earth abundant *** for future catalytic applications in the energy sector.

关键词： oxygen ev.lution reaction liquid atomic layer depositi on catalysis iridium core-shell nano particles

LIOUv.LLE TYPE THEOREM FOR THE STATIONARY EQUATIONS OF MAGNETO-HYDRODYNAMICS

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Acta Mathematica Scientia 2019年第2期39卷 491-497页

作者： simon SCHULZ Mathematical Institute University of Oxford

We show that any smooth solution(u, H) to the stationary equations of magnetohydrodynamics belonging to both spaces L^6(R^3) and BMO^(-1)(R^3) must be identically *** is an extension of prev.ous results, all of which systematically required stronger integrability and the additional assumption ▽u, ▽H∈L^2(R^3), i.e., finite Dirichlet integral.

关键词： Liouv.lle theorem Caccioppoli inequality Nav.er-Stokes equations MHD

Some remarks and problems on complex homogeneous domains Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

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Science China Mathematics 2006年第11期49卷 1655-1661页

作者： GINDIKIN simon Department of Mathematics Hill Center Rutgers University110 Frelinghysen RoadPiscatawayNJ 088548019USA

We discuss some problems on rigidity of canonical realizations of complex homogeneous domains at Cn

关键词： complex homogeneous domain, Siegel domain, Cartan domain, homogeneous cone, tube domain, Cauchy kernel.