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Analysis of the 3' ends of tRNA as the cause of insertion sites of foreign DNA in Prochlorococcus

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 708-718页

作者： Hai-lan LIU jun ZHU Institute of Bioinformaties College of Agriculture and Biotechnology Zhejiang University Hangzhou 310029 China Institute of Maize Research College of Agriculture Sichuan Agricultural University Ya'an 625014 China

The purpose of this study was to investigate the characteristics of transfer RNA(tRNA) responsible for the association between tRNA genes and genes of apparently foreign origin(genomic islands) in five high-light adapted Prochlorococcus *** bidirectional best BLASTP(basic local alignment search tool for proteins) search and the conservation of gene order against each other were utilized to identify genomic islands,and 7 genomic islands were found to be immediately adjacent to tRNAs in Prochlorococcus marinus AS9601,11 in *** MIT9515,8 in *** MED4,6 in *** MIT9301,and 6 in *** *** Carlo simulation showed that tRNA genes are hotspots for the integration of genomic islands in Prochlorococcus *** tRNA genes associated with genomic islands showed the following characteristics:(1) the association was biased towards a specific subset of all iso-accepting tRNA genes;(2) the codon usages of genes within genomic islands appear to be unrelated to the codons recognized by associated tRNAs;and,(3) the majority of the 3' ends of associated tRNAs lack CCA *** findings contradict previous hypotheses concerning the molecular basis for the frequent use of tRNA as the insertion site for foreign genetic *** analysis of a genomic island associated with a tRNA-Asn gene in *** MIT9301 suggests that foreign genetic material is inserted into the host genomes by means of site-specific recombination,with the 3' end of the tRNA as the target,and during the process,a direct repeat of the 3' end sequence of a boundary tRNA(namely,a scar from the process of insertion) is formed elsewhere in the genomic *** the analysis of the sequences of these targets,it can be concluded that a region characterized by both high GC content and a palindromic structure is the preferred insertion site.

关键词： Genomic islands Prochlorococcus Transfer RNA(tRNA) Palindromic structure Codon usage

A novel hybrid method for aerodynamic noise prediction of high-lift devices

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Chinese Journal of Aeronautics 2023年第9期36卷 151-161页

作者： jun TAO Gang sun Department of Aeronautics&Astronautics Fudan UniversityShanghai 200433China Key Laboratory of Aerodynamic Noise Control China Aerodynamics Research and Development CenterMianyang 621000China

Aerodynamic noise of High-Lift Devices(HLDs)is one of the main sources of airframe noise,and has immediate impacts on the airworthiness certification,environmental protection and security of commercial *** this study,a novel hybrid method is proposed for the aerodynamic noise prediction of HLD.A negative Spalart-Allmaras(S-A)turbulence model based Improved Delayed Detached Eddy Simulation(IDDES)method coupling with AFT-2017b transition model is developed,in order to elaborately simulate the complex flow field around the HLD and thus obtain the information of acoustic sources.A Farassat-Kirchhoff hybrid method is developed to filter the spurious noise sources caused by the vortex motions in solving the Ffowcs Williams-Hawkings(FW-H)equation with permeable integral surfaces,and accurately predict the far-field noise radiation of the *** results of the 30P30N HLD indicate that,the computational Sound Pressure Levels(SPLs)obtained by the Farassat-Kirchhoff hybrid method conform well with the experimental ones in the spectrum for the given observation point,and are more accurate than those obtained by the Farassat 1A *** on the hybrid method,the acoustic directivity of the HLD of a commercial aircraft is obtained,and the variation of the SPLs in the spectrum with the deflection angle of the slat is analyzed.

关键词： Aerodynamic noise Farassat-Kirchhoff hybrid method High-lift devices IDDES Negative S-A turbulence model

How Many Pathways We Have for the Marine Carbon Neutrality

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Journal of Earth Science 2023年第5期34卷 1621-1623页

作者： jun sun Institute for Advanced Marine Research CUG Guangzhou 511462China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China College of Marine Science and Technology China University of GeosciencesWuhan 430074China

Global warming is one of the major challenges that the international community is currently *** Intergovernmental Panel on Climate Change(IPCC)has indicated that if the concentration of greenhouse gases in the atmosphere continues to rise,global warming is expected to pose risks to future food security,as well as to human health and wealth in the 21st *** became the world’s largest emitter of greenhouse gases in *** 2018,the global emission of greenhouse gases was 33.1 billion metric tons of CO_(2),with China accounting for 28%of the total global emission,ranking first *** to estimates by the Chinese Academy of Engineering,China will reach its peak carbon dioxide emissions in 2027 at 12.2 billion metric tons of CO_(2),making it imperative to achieve carbon neutrality and achieve harmony between humans and nature as soon as possible.

关键词： gases Marine harmony

Effect of sintering process on microstructure and magnetic properties of high frequency power ferrite

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Rare Metals 2006年第Z1期25卷 509-514页

作者： sun Ke lan Zhongwen CHEN Shengming sun Yueming YU Zhong State Key Laboratory of Electronic Thin Films and Integrated Devices UESTCChengdu 610054China Jiangsu Research Center of Magnetic Materials and Devices Engineering and Technology Wuxi 214199China

An oxide ceramic process was adopted to prepare high frequency manganese-zinc(MnZn)power *** combination with the microstructure analysis of material,the influences of sintering process on initial permeability(μ_(i))and high frequency loss in unit volume(P_(cv))of MnZn power ferrite were *** results show that in order to obtain fine microstructure and high frequency properties,the preferable sintering temperature and atmosphere are 1230℃and oxygen partial pressure(P_(O_(2)))of 4%,respectively.

关键词： manganese-zinc ferrite microstructure initial permeability sintering process

Effects of Bushen Yiqi Huoxue Decoction in Treatment of Patients with Diminished Ovarian Reserve:A Randomized Controlled Trial

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Chinese Journal of Integrative Medicine 2022年第3期28卷 195-201页

作者： ZHOU Jing PAN Xin-yao LIN Jin ZHOU Qi lan Li-kun ZHU jun DUAN Ru WANG lan sun Yan WANG Ling Laboratory for Reproductive Immuno logy Hospital&Institute of Obstetrics and Gyn ecologyShan ghai Medical CollegeFudan UniversityShanghai(200000)China Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases Shanghai(200000)China Academy of Integrative Medicine of Fudan University Shanghai(200000)China Yangpu Hospital of Traditional Chinese Medicine Shanghai(200000)China Second Affiliated Hospital of Hexi University ZhangyeGansu Province(743000)China Department of Obstetrics and Gyn ecology Wenling People's HospitalWenzhou Medical UniversityWenzhouZhejiang Provinee(325000)China Regulatory Commissi on Office of the New Cooperative Medical Scheme Eryuan CountyDaliYunnan Province(671000)China

Objective:To explore the therapeutic effect of Bushen Yiqi Huoxue Decoction BYHD)in patients with diminished ovarian reserve(DOR).Methods:A total of 180 patients with DOR diagnosed from December2013 to December 2014 were equally assigned into progynova and duphaston(E+D)group,Zuogui Pill group and BYHD group with 60 cases in each by computerized *** received E+D,Zuogui Pill or BYHD for 12 months,*** stimulating hormone(FSH),luteinizing hormone(LH),estradiol(E_(2)),anti-Mullerian hormone(AMH),antral follicle count(AFC),ovarian volume,endometrial thickness,and the resistance indices(Rls)of ovarian arteries and uterine arteries were observed before and after ***:Nine women(4 from the E+D group,3 from the Zuogui Pill group,and 2 from the BYHD group)withdrew from the *** 6 months,Zuogui Pill and BYHD significantly decreased FSH and LH and increased endometrial thickness and AMH(all Plancing hormone levels,promoting ovulation,and repairing the thin *** combination of tonifying Shen(Kidney),benefiting qi and activating blood circulation may be a promising therapeutic strategy for DOR.

关键词： Bushen Yiqi Huoxue Decoction diminished ovarian reserve randomized controlled trial Chinese medicine

Investigation of the roles of lignin in biomass-based hydrogel for efficient desalination

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Frontiers of Chemical Science and Engineering 2023年第7期17卷 954-965页

作者： Qizhao Shao lan sun Xinzhou Wu Dafeng Zheng School of Chemistry and Chemical Engineering Guangdong Engineering Research Center for Green Fine ChemicalsSouth China University of TechnologyGuangzhou 510640China

The shortage of freshwater has become a global challenge,and solar-driven interfacial evaporation for desalination is a promising way to alleviate the *** develop highly efficient and environmentally friendly photothermal evaporator,the hydroxyethyl cellulose(HEC)/alkaline lignin(AL)/graphene oxide(GO)hydrogels(CLGs)with remarkable evaporative performance were successfully fabricated by a facile solgel method using biomass *** influence of AL content on the physicochemical properties of the evaporator was *** increasing content of AL improves the mechanical properties,saturated water content and crosslink density of the *** designed materials exhibit outstanding thermal insulation capacity(the thermal conductivity of less than 0.05 W·m^(–1)·K^(-1))and high light absorption capacity of more than 97%.The solar evaporation efficiency and water evaporation rate of the HEC/64 wt%of AL/GO hydrogels(CLG4)achieve 92.1%and 2.55 kg·m^(–2)·h^(-1) under 1 sun,*** salt resistance test results reveal that the evaporation rate of the CLG4 can still reach 2.44 kg·m^(–2)·h^(–1) in 3.5 wt% NaCl *** solar evaporation rate of the CLG4 can maintain in the range of 2.45–2.59 kg·m^(–2)·h^(–) in five *** low-cost lignin-based photothermal evaporator offers a sustainable strategy for desalination.

关键词： lignin photothermal cellulose desalination hydrogel

Theoretical Study on Reaction Mechanism of Aluminum-Water System

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Chinese Journal of Chemical Physics 2008年第3期21卷 245-249页

作者： Yun-lan sun Yan Tian Shu-fen Li Department of Chemical Physics University of Science and Technology of China Hefei 230026 China School of Metallurgy and Resources Anhui University of Technology Maanshan 243002 China

A theoretical study on the reaction of aluminum with water in the gas phase was performed using the hybrid density functional B3LYP and QCISD（T） methods with the 6-311＋G（d,p） and the 6-311＋＋G（d,p） basis sets. The results show that there are three possible reaction pathways that involve four isomers, seven transition structures, and two possible products for the reaction of aluminum with water. The two most favorable reaction pathways were found, whose intermediates and products agreed quite well with experimental results. The enthalpy and Gibbs free energy change of the reaction between A1 and H2O at 298 and 2000 K were calculated. Some results are also in good agreement with the previous calculations or experimental results.

关键词： Aluminum Water Reaction mechanism Hybrid density functional theory

Novel HBD-Containing Zn (dobdc) (datz) as efficiently heterogeneous catalyst for CO_(2) chemical conversion under mild conditions

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Green Energy & Environment 2021年第1期6卷 66-74页

作者： Jianwen lan Ye Qu Ping Xu Jianmin sun State Key Laboratory of Urban Water Resource and Environment MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and StorageSchool of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin150080China

A novel Zn-based metal–organic framework Zn(dobdc)(datz)[Zn_(2)(H2dobdc)(datz)2$1.5DMF]with plentiful hydrogen bond donors(HBD)groups was facilely synthesized from mixed *** dual activation of metal Zn sites and HBD groups for epoxides by forming Zn–O adduct and hydrogen bonds facilitated the ring-opening of epoxide substrate,which is critical for the subsequent CO_(2) ***,the existence of micropores and N-rich units in Zn(dobdc)(datz)afforded affinity towards CO_(2),which is beneficial to further improvement on catalytic CO_(2) conversion ***,Zn(dobdc)(datz)/Bu4NBr system was proved efficient heterogeneous catalyst for the CO_(2) cycloaddition with epoxides,and 98%propylene carbonate yield was obtained under mild conditions(80C,1.5 MPa and solvent-free).In addition,Zn(dobdc)(datz)/Bu4NBr exhibited remarkable versatility to different epoxides and could be completely recycled over six runs with high catalytic *** highly stable,easily recycle and solvent-free Zn-based MOF reported here displays eco-friendly and efficient performance to CO_(2)conversion.

关键词： Heterogeneous Zn-MOF catalyst HBD groups CO_(2)conversion High versatility and recyclability Mild conditions

The effect of noise exposure on sleep quality of urban residents:A comparative study in Shanghai,China

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Building Simulation 2023年第4期16卷 603-613页

作者： Xinbo Xu Li lan Yuxiang sun Zhiwei Lian School of Design Shanghai Jiao Tong UniversityShanghai 200240China China Institute of Urban Governance Shanghai Jiao Tong UniversityShanghai 200030China

Noise exposure is becoming extremely common in urban area,but its specific impact on sleep remains *** the limitations of previous researches,a field study which can conduct both horizontal and longitudinal analysis was *** participants were tested during two weeks in their homes,and the noise level of bedroom was artificially regulated by changing the status of window and *** the 1050 test nights in 75 households,noise exposure was reflected from both instrument monitoring at night and perception questionnaire in the morning,and sleep quality was accessed from actigraphy and *** analysis results showed that,92.3%of the bedroom acoustic environment did not meet the minimum requirements of Chinese standards,and 87.9%of subjects had ever experienced harmful noise during the test ***,sleep quality was affected by noise exposure from the perspective of both physiological and psychological;the duration of rapid eye movement(REM)sleep was significantly(p<0.05)shortened with the increase of sound intensity,the duration of deep sleep shortened and subjective sleep quality worsened significantly(p<0.05)with the increase of acoustic sensation *** addition,females were more sensitive to noise exposure and their subjective sleep quality was more likely to be influenced by *** study has important implications for acoustic environment design of bedrooms in cities,and suggested more attention should be paid to the anxiety caused by noise exposure.

关键词： noise exposure sleep quality sound intensity subjective perception urban governance