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EPR and Magnetic Susceptibility Studies of Cr^(3+) Ions in the 70TeO_2·25B_2O_3·5PbO Glass Matrix

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Journal of Materials Science & Technology 1997年第5期13卷 374-378页

作者： Peteanu, M. simon, v. Muresan, N. Ardelean, I. Faculty of Physics Babes-Bolyai University 3400 Cluj-Napoca Romania Dept. of Physics University of Oradea 3700 Oradea Romania

By using EPR and magnetic susceptibility measurements, the Cr ion distribution in the xCr2O3.(1-x)[70TeO2·25B2O3·5PbO] glasses with 0＜x≤20 mol% was studied. EPR inv.stigation ev.dencedthe presence of Cr3+ ions in agreement with the experimentally obtained atomic magnetic moment v.lues. For concentrations x≤3 mol%, the isolated Cr3+ ions coexist with those coupledby dipole-dipole interactions. For x＞3 mol%, the Cr3+ ions participate in superexchange interactions and are predominantly antiferromagnetically coupled.

关键词： PbO Ions in the 70TeO2 Glass Matrix EPR and Magnetic Susceptibility Studies of Cr Cr

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 k.y 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 k.pt 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

Adenosine deaminase 2 regulates the activ.tion of the toll-lik. 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 Sk.ldin Mak.ym 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-lik. 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 mark.dly 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 block.ng 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 Ledendeck.r simon Geiger k.tharina Hengge Joohyun Lim Serhiy Cherev.0} Andrea M. Mingers Daniel Gohl Guilherme v. Fortunato Daniel Jalalpoor Ferdi Schuth Christina Scheu k.rl 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 thick.ess 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

Effect of Surfactants on the Thermoelectric Performance of Double-Walled Carbon Nanotubes

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Energy & Env.ronmental Materials 2023年第1期6卷 274-280页

作者： Zak.ria Saadi simon G.k.ng Jose v.Anguita v.ad Stolojan S.Rav. P.Silv. Department of Electrical and Electronic Engineering Advanced Technology InstituteUniversity of SurreyGuildford GU27XHUK

Thermoelectrics are a promising solution to the recov.ry of some of the 60%of the worldwide energy wasted as ***,their conv.rsion efficiency is low and the best performing materials are brittle,toxic,and made of expensiv. *** challenge in dev.loping better performing materials is in disrupting the electrical v. thermal conductiv.ty correlation,to achiev. low thermal conductiv.ty simultaneously with a high electrical *** nanotubes allow for the decoupling of the electronic density of states from the phonon density of states and this paper shows that flexible,thin films of double-walled carbon nanotube(DWCNT)can form effectiv. n-and p-doped semiconductors that can achiev. a combined Seebeck.coefficient of 157.6µv.k.(−1),the highest reported for a single DWCNT dev.ce to *** is achiev.d through selected surfactant doping,whose role is correlated with the length of the hydrocarbon chain of the hydrophobic tail group of the surfactant’s *** functionalized with Triton X-405 show the highest output power consisting of a single junction of p-and n-type thermoelectric elements,reaching as high as 67 nW for a 45 k.temperature *** enabling flexible,cheaper,and more efficient thermoelectric generators through the use of functionalized CNTs.

关键词： carbon nanotubes DWCNT functionalization surfactant thermoelectric

Recalcitrant distal humeral non-union following prev.ous Leiomyosarcoma excision treated with retainment of a radiated non-angiogenic segment augmented with 20 cm free fibula composite graft: A case report

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World Journal of Orthopedics 2019年第4期10卷 212-218页

作者： Martin Gathen Grayson Norris simon k.y Peter v.Giannoudis Department of Orthopedics and Trauma Surgery University Hospital of Bonn Academic Department of Trauma and Orthopaedics School of Medicine University of Leeds Plastic and Reconstructiv. Surgery School of Medicine University of Leeds

BACk.ROUND Leiomyosacromas in the Extremities are rare malignant smooth muscle *** radiation therapy, in combination with wide surgical excision allows the best chance of treatment. During the follow up pathological fractures are common complications that can be accompanied by Implant failure and defect situations that are most challenging in their *** SUMMARY We present a case of a 52-year-old female suffering from a pathological fracture of the humeral shaft 10 yr after resection of a Leiomyosarcoma and postoperativ. radiotherapy. She dev.loped implant failure after retrograde nailing and another failure after rev.sion to double plate fixation. In a two-stage rev.sion, the implants were remov.d and the huge segmental defect created after debridement was bridged by a compound osteosynthesis with nancy nails and bone cement for formation of the induced membrane. Due to the prev.ous radiotherapy treatment,20 cm of the humeral shaft were declared dev.scularized but were left in situ as a scaffold. In the second stage, a v.scularized fibula graft was used in combination with a double plate fixation and autologous spongiosa grafts for final *** This combinatory treatment approach led to a successful clinical outcome and can be considered in similar challenging cases.

关键词： Humerus Fibular graft Bone tumor Osseous defect Implant failure Leiomyosarcoma Case report

The QT interv.l in Park.nson′s disease:a systematic rev.ew

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Journal of Geriatric Cardiology 2024年第9期21卷 855-864页

作者： simon W Rabk.n Div.sion of Cardiology University of British ColumbiaVancouverBC V5Z 1M9Canada

Back.round PD(PD)is associated with a twofold increase in the risk.of death especially sudden death.A predisposing factor for cardiac sudden death is prolongation of the QT *** study ev.luated the potential association between QT interv.l and *** A systematic search was conducted of Medline and EMBASE using the search terms“PD”AND“QT interv.l”OR“Cardiac Repolarization”to identify *** Sev.n studies with persons with PD(n=981)and control groups were *** was a significant difference in QT interv.l comparing patients with PD and persons without *** odds ratio showed a significant(Pv.l to the sev.rity of PD as assessed by Hoehn–Yahr classification(n=6),there was a significant(P=0.004)ov.rall correlation between QT interv.l and the sev.rity of *** was little publication *** data directly examining patients with PD tak.ng any drug than might prolong QT do not support an association between these mediations and QT *** Indiv.duals with PD hav. a longer QT interv.l than indiv.duals without *** QT interv.l is associated with a greater sev.rity of PD and a greater probability of dev.loping more sev.re *** QT interv.l should be considered in assessment of PD and possibly as a target for the treatment of PD.

关键词： QT QTc Focus

Fate plasticity in the intestine: The dev.l is in the detail

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World Journal of Gastroenterology 2019年第25期25卷 3116-3122页

作者： simon Buczack. Cambridge Stem Cell Institute Jeffrey Cheah Biomedical CentreAddenbrooke’s Biomedical Campus

The intestinal epithelium possesses a remark.ble ability for both proliferation and *** last two decades hav. generated major adv.nces in our understanding of the stem cell populations responsible for its maintenance during homeostasis and more recently the ev.nts that occur during injury induced *** fundamental discov.ries hav. capitalised on the use of transgenic mouse models and in v.v. lineage tracing to mak. their *** is ev.dent that maintenance is driv.n by rapidly proliferating crypt base stem cells,but complexities associated with the technicality of mouse modelling hav. led to sev.ral ov.rlapping populations being held responsible for the same ***,it has been shown that essentially any population in the intestinal crypt can rev.rt to a stem cell state giv.n the correct stimulus during epithelial *** these observ.tions are profound it is uncertain how relev.nt they are to human intestinal homeostasis and ***,these recent studies are presented,in context with technical considerations of the models used,to argue that their conclusions may indeed not be applicable in understanding“homeostatic regeneration”and experimental suggestions presented for v.lidating their results in human tissue.

关键词： Intestinal stem cell Plasticity Lgr5 Regeneration