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Design of Fe–Mn–Ag Alloys as Potential Candidates for Biodegradable Metals

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Acta Metallurgica Sinica(English Letters) 2018年第6期31卷 584-590页

作者： ruo-yu liu Ran-Gan He Li-Qun Xu Sheng-Feng Guo Faculty of Materials and Energy Southwest University

In this work,a series of biodegradable pure iron,Fe–30Mn and Fe–30Mn–Ag alloys were developed by using a rapid solidification technology.A fine a-Fe dendrite was formed in pure iron,resulting in a high compressive yield strength of above 300 *** Fe–30Mn alloy doped with only 1%Ag exhibited a significant increase in the degradation rate in simulated body fluid due to the precipitation of Ag-rich particles in alloy matrix and the induction of the microgalvanic *** addition,the novel Fe–30Mn–Ag alloy also exhibited a good magnetic compatibility and offered a closely approaching requirement for biodegradable medical applications.

关键词： Biodegradable metals Fe-based alloys Corrosion rate Magnetic compatibility

Implication from GRB 221009A:Can TeV emission come from the GRB prompt phase?

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 139-149页

作者： Kai Wang Zhi-Peng Ma ruo-yu liu yuan-Chuan Zou Zhuo Li Zi-Gao Dai Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratoryof Modern Astronomy and Astrophysics Ministry of EducationNanjing UniversityNanjing 20023China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Recently,the B.O.A.T.(“brightest of all time”)gamma-ray burst,dubbed GRB 221009A,was detected by various ***,the GRB presented very-high-energy(VHE,energy above 0.1 Te V)gamma-ray emission with energy extending above 10 Te V,as reported by the Large High Altitude Air Shower Observatory(LHAASO).We here demonstrate that the VHE and especially>10 Te V emission may originate from the internal hadronic dissipation of the GRB,without the need of invoking any exotic processes as suggested by some previous *** possible prompt origin of LHAASO photons may imply the first detection of the GRB prompt phase in the VHE *** also discuss the constraints on the properties of the GRB ejecta from multiwavelength and multi-messenger observations,which favors a magnetically dominated GRB *** suggested Poynting-flux-dominated GRB ejecta in this work supports the Blandford&Znajek(BZ)mechanism as the possible central engine model of GRB,as well as the possible strong magnetic dissipation and acceleration.

关键词： cosmological neutrinos neutrino astronomy high energy astrophysics gamma-ray bursts cosmic rays

Development of study on the dynamic characteristics of deep water mooring system

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Journal of Marine Science and Application 2007年第3期6卷 17-23页

作者： TANG You-gang ZHANG Su-xia ZHANG ruo-yu liu Hai-xiao School of Civil Engineering Tianjin University Tianiin 300072 China

To meet the needs of those exploiting deepwater resources, TLP and SPAR platforms are used in some areas and are considered excellent platforms in deep water. However, many problems remain to be resolved. The design of mooring systems is a key issue for deep water platforms. Environmental loads in deep water effect the physical characteristics of mooring line materials. The configuration and analysis of mooring systems involve nonlinearity due to this fluid-solid coupling, nonlinear hydrodynamic forces, and their effects on stability of motion. In this paper, some pivotal theories and technical questions are presented, including modeling of mooring lines, the theory and method of coupled dynamics analysis on the mooring system, and the development of methodologies for the study of nonlinear dynamics of mooring systems. Further study on mooring systems in deep water are recommended based on current knowledge, particularly dynamic parameters of different materials and cable configuration, interactions between seabed and cable, mechanisms of mooring system response induced by taut/slack mooring cables, discontinuous stiffness due to system materials, mooring construction, and motion instability, etc.

关键词： mooring in the deep water platform in the deep water dynamic response stability of motion

Challenges and countermeasures for developing countries in addressing loss and damage caused by climate change

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Advances in Climate Change Research 2024年第2期15卷 353-363页

作者： Shuo liu yu-E LI Bin WANG An-Dong CAI Chao FENG Hua LAN ruo-Chen ZHAO Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Agricultural Environment Ministry of Agriculture and Rural AffairsBeijing 100081China China Clean Development Mechanism Fund Management Center Beijing 100045China School of International Law China University of Political Science and LawBeijing 100088China

Loss and damage caused by extreme climate events have attracted increasing *** 28th Conference of the Parties to the United Nations Framework Convention on Climate Change(hereinafter referred to as the Convention)has agreed to adopt Loss and Damage Fund agreement,which identified the source of funding and the funds to be entrusted to the World ***,there is still ambiguous that how to allocate the funds could accelerate the effectiveness of meeting the needs for developing ***-disaster prevention and preparedness is one of the most effective measures to deal with loss and damage,which closely related to *** studies rarely analyzed quantitatively the financial needs of pre-disaster prevention and preparedness relating to adaptation to reduce loss and *** on the official reports submitted by countries under the Convention,this study analyzes the annual change in the total financial support provided by developed countries to developing countries,the proportion of pre-disaster prevention and preparedness in the adaptation needs of developing countries,and the progress in raising the current annual funding target of 100 billion USD for developed countries,to reveal the financial and technical challenges facing by developing countries on addressing loss and *** results show that by 2030,the total adaptation financial needs of developing countries are estimated to be about 3.8 trillion USD,of which pre-disaster prevention matters account for about 9%.Therefore,by 2030,developing countries will need about 342 billion USD in pre-disaster prevention and preparedness finance to withstand loss and *** addition,developing countries face a lack of technical methods to quantify information about their *** on the above analysis,this study puts forward countermeasures and suggestions,including strengthening the allocation amount of loss and damage fund on pre-disaster warning,prevention and control actions,and

关键词： Loss and damage Funding mechanism Pre-disaster warning and preparedness Convention negotiations Countermeasures

Dexamethasone increases susceptibility of Aspergillus fumigatus to hydrogen peroxide via down-regulation of Afyapl gene expression in vitro

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Chinese Medical Journal 2011年第22期124卷 3773-3777页

作者： XU Hui LI Li-juan WAN Zhe LI ruo-yu liu Wei Department of Dermatology Peking University First Hospital and Research Center for Medical Mycology Peking University Beijing 100034 China

Background Glucocorticoid is speculated to be able to have Aspergillus fumigatus （A. tum/gatus） I^e~ng more susceptible to reactive oxygen species （ROS） by inhibiting Afyapl, the transcription factor activating protein-1 （AP-1） homologue in A. fumigatus, which may provide a clue to expand the clinical use of glucocorticoid in patients with fungal infections. In this study, we used dexamethasone to determine the direct effect on oxidative killing susceptibility of A. fumigatus in vitro, as well as the expression level of Afyapl gene and its target genes （catalase and superoxide dismutase （SOD） genes）. Methods A. fumigatus spores were treated with different concentrations （0, 0.02, 0.2 mg/ml） of glucocorticoids and assigned to four groups （A： 0.5 hour, B： 2 hours, C： 7 hours, D： 16 hours） according to the time of treatment. The H202 oxidative killing assay was done, using the standard method-spot test, in each group of A. fumigatus. We measured the oxidative killing susceptibility as well as the expression level of the gene Afyapl, CATA, SOD1 and SOD2 in A. fumigatus at each group. The antifungal susceptibility to itraconazole and amphotericin B in each group of A. fumigatus was also measured with M38-A2 method. Results The oxidative killing susceptibility of A. fumigatus was increased, consistent with the reduction of Afyapl, CATA, SOD1 and SOD2 gene expression level after being treated with dexamethasone for 0.5 hours. However, these observations were disappeared along with being treated for longer time. The antifungal susceptibility to itraconazole and amphotericin B in the A. fumigatus strains treated with dexamethasone indicated no change, compared with those without dexamethasone treatment. Conclusion Dexamethasone can have A. fumigatus being more susceptible to ROS when treated for shorter period （0.5 to 2 hours） via the reduction of Afyapl gene expression as well as the down-stream enzyme-coding gene expression.

关键词： Aspergillus fumigatus Afyapl dexamethasone oxidative killing

Chapter 6 Multimessenger Physics

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Chinese Physics C 2022年第3期46卷 139-152页

作者： Zhuo Li Giuseppe Di Sciascio Quan-Bu Gou Yi-Qing Guo Hao-Ning He ruo-yu liu Kai Wang INFN-Roma Tor Vergata Via della Ricerca Scientifica 100133 RomeItaly Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China Department of Astronomy School of PhysicsHuazhong University of Science and TechnologyWuhan 430074China

Combining observations of multi-messengers help in boosting the sensitivity of astrophysical source searches,and probe various aspects of the source *** this chapter we discuss how LHAASO observations of very high energy(VHE)gamma rays in combination with telescopes for the other messengers can help in solving the origins of VHE neutrinos and galactic and extragalactic cosmic rays.

关键词： Cosmic ray gamma-ray neutrino LHAASO

Relationship between antifungal resistance of fluconazole resistant Candida albicans and mutations in ERG11 gene

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Chinese Medical Journal 2010年第5期123卷 544-548页

作者： FENG Li-juan WAN Zhe WANG Xiao-hong LI ruo-yu liu Wei Department of Dermatology Peking University First Hospital Research Center for Medical Mycology Peking University Beijing 100034 China

Background The cytochrome P450 lanosterol 14a-demethylase （Ergllp） encoded by ERG11 gene is the primary target for azole antifungals. Changes in azole affinity of this enzyme caused by amino acid substitutions have been reported as a mechanism of azole antifungal resistance. This study aimed to investigate the relationship between amino acid substitutions in Erg11 p from fluconazole resistant Candida a/bicans （C. albicans） isolates and their cross-resistance to azoles. Methods Mutations in ERG11 gene were screened in 10 clinical isolates of fluconazole resistant C. albicans strains. DNA sequence of ERG11 was determined by PCR based DNA sequencing. Results In the 10 isolates, 19 types of amino acid substitutions were found, of which 10 substitutions （F72S, F103L, F1451, F198L, G206D, G227D, N349S, F416S, F422L and T482A） have not been reported previously. Mutations in ERG11 gene were detected in 9 isolates of fluconazole resistant C. albicans, but were not detected in 1 isolate. Conclusions Although no definite correlation was found between the type of amino acid substitutions in Ergllp and the phenotype of cross-resistance to azoles, the substitutions F72S, F1451 and G227D in our study may be highly associated with resistance to azoles because of their special location in Erg11p.

关键词： fluconazole Candida albicans ERGll gene drug resistance

Double active sites promoting hydrogen evolution activity and stability of CoruoH/Co_(2)P by rapid hydrolysis

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Chinese Chemical Letters 2024年第7期35卷 206-211页

作者： Bin Dong Ning yu Qiu-yue Wang Jing-Ke Ren Xin-yu Zhang Zhi-Jie Zhang ruo-Yao Fan Da-Peng liu Yong-Ming Chai State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Cobalt-based phosphides show excellent hydrogen evolution reaction(HER)performance,however,improving the intrinsic activity and stability of it in alkaline electrolyte still remains a ***,CoruoH/Co_(2)P/CF with heterojunction structure was developed by means of molten salt and rapid hydrolysis(30 s).The OH-from rapid surface hydrolysis of Co_(2)P as a hydrogen adsorption site can facilitate the formation of thin CoruoH layer as a water dissociation site,which may bring out better synergistic effect for alkaline ***,the covering of CoruoH can improve the stability of Co_(2)P for *** drives at 100 mA/cm^(2),it only requires overpotential of 81 mV in 1.0 mol/L KOH(25℃).Even at higher current density(1000 mA/cm^(2)),CoruoH/Co_(2)P/CF can also operate stability for at least 100 *** coupling with NiFe-LDH/IF in a two-electrode system,the voltage of NiFe-LDH/IF(+)||CoruoH/Co_(2)P/CF(-)at 1000 mA/cm^(2)is merely 1.77 V with 100 h,demonstrating great potential for water *** implementation of this work provides a new strategy and reference for the further improvement of transition metal phosphides as HER electrocatalysts.

关键词： CoruoH/Co_(2)P/CF Enhanced activity and stability Double active site Large current density Hydrogen evolution reaction

Antifungal activity of ibuprofen against aspergillus species and its interaction with common antifungal drugs

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Chinese Medical Journal 2010年第19期123卷 2701-2705页

作者： LI Li-juan CHEN Wei XU Hui WAN Zhe LI ruo-yu liu Wei Department of Dermatovenerology Peking University First Hospital Research Center for Medical Mycology Peking University Beijing 100034 China

Background The incidence of invasive aspergillosis （IA） has increased in frequency in immunocompromised patients with a variety of diseases. The poor prognosis might be due to limited treatment option. This study aimed to evaluate antifungal activity of ibuprofen against clinical isolates of aspergillus species, as well as its interaction with azoles or with amphotericin B or with micafungin. Methods Antifungal activity of ibuprofen against 10 strains of Aspergillus fumigatus, Aspergillus flavus, and Aspergillus terreus were tested with both disk diffusion assay and standard broth microdilution method. To determine whether ibuprofen combined with itraconazole, voriconazole, amphotericin B, or micafungin had interactive effects on aspergillus spp., we used both disk diffusion assay and Chequerboard method. Results As for disk diffusion method, ibuprofen produced a zone of growth inhibition with diameters of （20.1±3.9） mm at 48 hours of incubation. As for broth microdilution method, the minimal inhibitory concentration （MIC） ranges of ibuprofen against aspergillus spp. were 1000-2000 μg/ml, and the minimal fungicidal concentration （MFC） ranges of that was 2000-8000 μg/ml. For 2 of 5 isolates, when ibuprofen combined with itraconazole or voriconazole, the zones of growth inhibition were larger than those of the individual drug. The results of Chequerboard method showed that fractional inhibitory concentration index （FICI） ranges were 1.125-2.500. Conclusions Ibuprofen is active against aspergillus spp.. And ibuprofen does not affect the in vitro activity of itraconazole, voriconazole, amphotericin B or micafungin against aspergillus spp.

关键词： aspergillus spp. ibuprofen antifungal susceptibility drug interaction