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儿童Ct辐射剂量:在瑞士建立一项基于年龄诊断参考水平的研究

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国际医学放射学杂志 2008年第A6期31卷 515-516页

作者： F.R.Verdun D.Gutierrez J.P.Vader A.Aroua L.t.Alamo-maestre F.Bochud 邓贺然 University Institute for Radiation Physics (IRA-DUM-SC) CHUV and University of Lausanne Grand-Pré 1 1007 Lausanne Switzerland.

本研究的目的是评估瑞士儿科病人在脑部、胸部、腹部Ct检查中受到的辐射剂量并建立一个不同年龄组的诊断参考水平。将表格送至10个儿童Ct扫描中心。

关键词： Ct 儿科学辐射剂量学辐射防护诊断参考水平

Universality test of short range nucleon-nucleon correlations in nuclei with strange and charmed probes

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Chinese Physics C 2022年第1期46卷 124-128页

作者： Yu.t.Kiselev NRC"Kurchatov Institute"-ItEP Moscow 117218 Russia

Understanding the EMC effect and its relation to the short-range nucleon-nucleon correlations(SRC)in nuclei is a major challenge for modem nuclear physics.One of the key aspects of the connection between these phenomena is the universality.the universality states that the SRC is responsible for the EMC effect and that the modification of the partonic structure of the SRC is the same in different nuclei.the flavor dependence of the universal-ity is one of the unanswered questions.the investigations conducted to date have demonstrated the existence and universality of the SRC for light u and d quarks.Recently,it was suggested that the universality for heavy flavors can be studied through their deep subthreshold production in yA and eA collisions.In this paper,we discuss an alternative possibility to access the strange and gluon high-A"structure of the SRC and to establish universality for heavy flavors using nuclear semi-inclusive deep inelastic scattering(nSIDIS),which probes different quark flavor combinations depending on the final state hadron.the specific reaction can be"tagged"by observation of a strange or charmed particle registered in coincidence with the scattering lepton.the universality of the SRC can be tested in the kinematic region,i.e.,X>1,where the contribution to the cross section from SRC becomes dominant.Exploring the strangeness,charmonium,and open charm will shed light on the role of quarks and gluons in nuclei,thereby developing an understanding of how nuclei emerge within QCD.

关键词： EMC effect strange and charm quarks in nuclei short-range nucleon correlation in nuclei

Numerical damage evaluation of perforated steel columns subjected to blast loading

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Defence technology（防务技术） 2022年第5期18卷 735-746页

作者： Mahmoud t.Nawar Ibrahim t.Arafa Osama M.Elhosseiny Structural Engineering Department Zagazig UniversityZagazig44519Egypt

the structural performance of perforated steel columns(PSCs)is significantly more complex than the one of solid web I-shaped elements under the diversity of blast loading scenarios.the damage criterion of PSCs is not only related to initial deformation response during the blast but also the residual axial load capacity and it can be considered as a reliable index after the blast effects.therefore,the PSCs damages will be studied in two stages;direct and post blast effects.In the present study,the dynamic response of PSCs was numerically evaluated under different levels of blast threats using LS-DYNA software.Extensive explicit finite element(FE)analyses are carried out to investigate the effect of various parameters,such as web opening shapes,boundary conditions and strengthening details on the damage index and toughness of the PSCs compared to the parent steel sections.the results of the comparative study show that the damage and toughness decrease when the support condition changes from pinned to fixed ends through the two stages of loadings.PSCs give high toughness compared to its parent sections during blast shock stage while,a remarkable decrease in toughness is observed during the application of axial gravity after blast shock.Furthermore,the web opening shapes have slight effects on the global dynamic behavior of PSCs,particularly in terms of residual capacity.On the contrary,the retrofitting strategy using both closed holes at end and vertical stiffeners have an effective enhancement to get higher toughness in case of the extreme blasts.

关键词： Perforated steel columns Blast load Damage criterion Numerical modeling Explicit finite element analysis Web-opening shapes

Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)nanophosphors prepared using citrate sol-gel method

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Journal of Rare Earths 2023年第3期41卷 358-364,I0002页

作者： V.M.Maphiri L.t.Melato M.R.Mhlongo t.t.Hlatshwayo t.E.Motaung L.F.Koao S.V.Motloung Department of Physics Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Mathematics Non Destructive Testing and PhysicsVaal University of TechnologyAndries Potgieter BlvdVanderbijlpark1900South Africa Department of Physics University of PretoriaPretoria0002South Africa Department of Chemistry School of Science in the College of Science Engineering and TechnologyUniversity of South AfricaPreller StreetMuckleneuk RidgeCity of TshwaneP.O Box 392UNISA 0003South Africa Department of Chemistry Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Department of Chemical and Physical Sciences Walter Sisulu UniversityMthathaSouth Africa

Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%tb^(3+)(ZAOt)nano-powders were synthesized via citrate sol-gel method.the AIx moles were varied in the range of 0.25≤x≤5.0.the X-ray powder diffraction(XRD)data reveal that for xthe prepared samples crystal structure consists of mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).the Raman and Fourier-trans form infrared(FtIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) spinel.Scanning electron microscopy(SEM)and transmission electron microscopy(tEM)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).the photoluminescence(PL)spectroscopy reveals emissions from both the host and tb^(3+)transitions.Emissions from tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)F_(6,5,4,2) and ^(5^)D_(4)→^(7)F_(6,5,4,3),respectively.the results confirm that the tb^(3+)occupation site depends on the Alx moles.the International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles.

关键词： Citrate sol-gel ZnAl_(2)O_(4)/ZnO tb^(3+)-doped Al_(x)moles Photoluminescence Rare earths

An alternative to MINFLUX that enables nanometer resolution in a confocal microscope

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Light(Science & Applications) 2022年第9期11卷 2077-2085页

作者： LUCIANO A.MASULLO ALAN M.SZALAI LUCIA F.LOPEZ MAURICIO PILO-PAIS GUILLERMO P.ACUNA fernando D.Stefani Centro de Investigaciones en Bionanociencias(CIBION) Consejo Nacionallde Investigaciones Cientificas y Técnicas(CONICET)Godoy Cruz 2390C1425FQD Ciudad Autónoma de Buenos AiresBuenos AiresArgentina Departamento de Fisica Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos AiresGuiraldes 2620C1428EHA Ciudad Autónoma de Buenos AiresBuenos AiresArgentina Department of Physics University of FribourgChemin du Musee 3Fribourg CH-1700Switzerland

Localization of single fluorescent emitters is key for physicochemical and biophysical measurements at the nanoscale and beyond ensemble averaging.Examples include single-molecule tracking and super-resolution imaging by single-molecule localization microscopy.Among the numerous localization methods available,MINFLUX outstands for achieving a~10-fold improvement in resolution over wide-field camera-based approaches,reaching the molecular scale at moderate photon counts.Widespread application of MINFLUX and related methods has been hindered by the technical complexity of the setups.Here,we present RAStMIN,a single-molecule localization method based on raster scanning a light pattern comprising a minimum of intensity.RAStMIN delivers~1-2nm localization precision with usual fluorophores and is easily implementable on a standard confocal microscope with few modifications.We demonstrate the performance of RAStMIN in localization of single molecules and super-resolution imaging of DNA origami structures.

关键词： resolution pattern enable

New microbial electrosynthesis system for methane production from carbon dioxide coupled with oxidation of sulfide to sulfate

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Journal of Environmental Sciences 2023年第3期125卷 786-797页

作者： Hiromi Kambara Ha t.t.Dinh Shuji Matsushita Yoshiteru Aoi tomonori Kindaichi Noriatsu Ozaki Akiyoshi Ohashi Department of Civil and Environmental Engineering Graduate School of EngineeringHiroshima University1–4–1KagamiyamaHigashi-HiroshimaHiroshima 739–8527Japan Faculty of Environment Ho Chi Minh City University of Natural Resources and Environment236 Le Van Sy1 WardTan Binh DistrictHo Chi Minh CityVietnam Agricultural technology Research Center Hiroshima Prefectural Technology Research Institute6869HaraHachihonmatsuHigashihiroshimaHiroshima 739–0151Japan Program of Biotechnology Graduate School of Integrated Sciences for LifeHiroshima University1–3–1KagamiyamaHigashi-HiroshimaHiroshima 739–8530Japan Department of Civil and Environmental Engineering Graduate School of Advanced Science and EngineeringHiroshima University1–4–1KagamiyamaHigashi-HiroshimaHiroshima 739–8527Japan

Microbial electrosynthesis system (MES) is a promising method that can use carbon dioxide,which is a greenhouse gas,to produce methane which acts as an energy source,without using organic substances.However,this bioelectrical reduction reaction can proceed at a certain high applied voltage when coupled with water oxidation in the anode coated with metallic catalyst.When coupled with the oxidation of HS–to SO_(4)^(2-),methane production is thermodynamically more feasible,thus implying its production at a considerably lower applied voltage.In this study,we demonstrated the possibility of electrotrophic methane production coupled with HS–oxidation in a cost-effective bioanode chamber in the MES without organic substrates at a low applied voltage of 0.2 V.In addition,microbial community analyses of biomass enriched in the bioanode and biocathode were used to reveal the most probable pathway for methane production from HS–oxidation.In the bioanode,electroautotrophic SO_(4)^(2-)production accompanied with electron donation to the electrode is performed mainly by the following two steps:first,incomplete sulfide oxidation to sulfur cycle intermediates (SCI) is performed;then the produced SCI are disproportionated to HS^(–)and SO_(4)^(2-).In the biocathode,methane is produced mainly via H_(2)and acetate by electronaccepting syntrophic bacteria,homoacetogens,and acetoclastic archaea.Here,a new ecofriendly MES with biological H_(2)S removal is established.

关键词： Microbial electrosynthesis system Low applied voltage Organic substrates Methane production Sulfur oxidation

the Arabidopsis thaliana HAK5 K＋ transporter Is Required for Plant Growth and K＋ Acquisition from Low K＋ Solutions under Saline Conditions

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Molecular Plant 2010年第2期3卷 326-333页

作者： Manuel Nieves-Cordones fernando Aleman Vicente Martinez Francisco Rubio Departamento de Nutricion Vegetal Centro de Edafologia y Biologia Aplicada del Segura CSlC Campus de Espinardo 30100 Murcia Spain

K＋ uptake in the high-affinity range of concentrations and its components have been widely studied. In Arabidposis thaliana, the AtHAK5 transporter and the AtAKt1 channel have been shown to be the main transport proteins involved in this process. Here, we study the role of these two systems under two important stress conditions： low K＋ supply or the presence of salinity. t-DNA insertion lines disrupting AtHAK5 and A tAKt1 are employed for long-term experi- ments that allow physiological characterization of the mutant lines. We found that AtHAK5 is required for K＋ absorption necessary to sustain plant growth at low K＋ in the absence as well as in the presence of salinity. Salinity greatly reduced AtHAK5 transcript levels and promoted AtAKtl-mediated K＋ efflux, resulting in an important impairment of K＋ nutrition. Although having a limited capacity, AtHAK5 plays a major role for K＋ acquisition from low K＋ concentrations in the presence of salinity.

关键词： Abiotic/environmental stress ion transport nutrition salinity transporters gene expression.

CO_(2)化学酶转化的突破:实现立体化学完全可控的可持续人工合成己糖

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Science Bulletin 2023年第20期68卷 2291-2292页

作者： Manfred t.Reetz tianjin Institute of Industrial Biotechnology Chinese Academy of SciencesTianjin 300308China Biocatalysis Section Max-Planck-Institut fur KohlenforschungMulheim an der Ruhr 45470Germany

the capture and transformation of the greenhouse gas CO_(2) into high-value products is currently of paramount importance worldwide,with many different approaches being conceived and tested[1-6].the transformation CO_(2) into carbohydrates is a particularly intriguing idea,but putting it into reality is challenging due to the necessary complete control in the creation of stereo-centers and ensuring sufficient yields.thus far,the results are not overly convincing[7].the inspiration for solving this fundamental problem is manifold,inter alia,because carbohydrates(sugars)contribute significantly to energy storage and provide carriers for human living,especially important biologically active substances.they also constitute the main resource for industrial biomanufacturing.

关键词：立体化学 manifold sugar

Voltammetric sensor based on cobalt-poly(methionine)-modified glassy carbon electrode for determination of estriol hormone in pharmaceuticals and urine

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Journal of Pharmaceutical Analysis 2019年第5期9卷 347-357页

作者： Eliziana S. Gomes fernando R.F. Leite Bruno R.L. Ferraz Henrique A.J.L. Mourao Andrea R. Malagutti Department of Pharmacy Faculty of Biological and Health Sciences Federal University of Jequitinhonha and Mucuri Valleys MGT 367 Highway e Km 583 CEP 39100-000 Diamantina MG Brazil Department of Biology Federal University of Espírito Santo CEP 29500-000 Alegre ES Brazil Institute of Science and technology Federal University of Jequitinhonha and Mucuri Valleys MGT 367 Highway e Km 583 CEP 39100-000 Diamantina MG Brazil

A voltammetric sensor based on the electropolymerization of cobalt-poly(methionine)(Co-poly(Met)) on a glassy carbon electrode (GCE) was developed and applied for the determination of estriol by differential pulse voltammetry (DPV) for the first time. the electrochemical properties of the Co-poly(Met)/GCE were analysed by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to characterize the polymers on the GCE surface. the deposition of the Co-poly(Met) film on the GCE surface enhanced the sensor electronic transfer. CV studies revealed that estriol exhibits an irreversible oxidation peak at t0.58 V for the Co-poly(Met)/GCE (vs. Ag/AgCl reference electrode) in 0.10 mol/L Britton-Robinson buffer solution (pH=7.0). Different voltammetric scan rates (10-200 mV/s) suggested that the estriol oxidation on the Co-poly(Met)/GCE surface is controlled by adsorption and diffusion processes. Based on the optimized DPV conditions, the linear responses for estriol quantification were from 0.596 μmol/L to 4.76 μmol/L (R2 =0.996) and from 5.66 μmol/L to 9.90 μmol/L (R2 =0.994) with a limit of detection (LOD) of 0.0340 μmol/L and a limit of quantification (LOQ) of 0.113 μmol/L. the DPV-Co-poly(Met)/GCE method provided good intra-day and inter-day repeatability with RSD values lower than 5%. Also, no interference of real sample matrices was observed on the estriol voltammetric response, making the DPV-Copoly( Met)/GCE highly selective for estriol. the accuracy test showed that the estriol recovery was in the ranges 96.7%-103% and 98.7%-102% for pharmaceutical tablets and human urine, respectively. the estriol quantification in pharmaceutical tablets performed by the Co-poly(Met)/GCE-assisted DPV method was comparable to the official analytical protocols.

关键词： Estriol Electroanalysis Differential pulse voltammetry Cobalt-poly(methionine) film-modified glassy carbon electrode