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国际食品法典委员会新版《食品卫生通则》的修订及思考

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现代预防医学 2024年第7期51卷 1212-1216页

作者：刘奂辰陈锦瑶张立实国家市场监督管理总局国家标准技术审评中心四川大学华西公共卫生学院/华西第四医院

国际食品法典委员会（CAC）于2020年发布了新版《食品卫生通则》，对标准的结构、定义、技术内容等做了修改和完善，明确了良好卫生规范的在食品安全管理中的重要作用，强调了危害分析与关键控制点在应对更复杂的食品安全问题方面的优... 详细信息

国际食品法典委员会（CAC）于2020年发布了新版《食品卫生通则》，对标准的结构、定义、技术内容等做了修改和完善，明确了良好卫生规范的在食品安全管理中的重要作用，强调了危害分析与关键控制点在应对更复杂的食品安全问题方面的优势，并补充了致敏原控制、食品安全文化等近年来食品安全领域标准化研究的最新成果。本文通过将新版标准与2003版《食品卫生通则》的对比，详细阐述和分析了新版标准的主要变化，为我国食品相关标准的制定和实施提供参考。

关键词：国际食品法典委员会食品卫生通则标准

基于CRISPR/Cas技术的传染性病原精准便携化检测系统

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分析化学 2024年第2期52卷 187-197页

作者：刘一辰赵茹健吕佰阳宋德锋唐艺丹姜艳芳李冰凌中国科学技术大学应用化学与工程学院中国科学院长春应用化学研究所电分析化学国家重点实验室吉林大学中日联谊医院普通外科吉林大学第一医院基因诊断中心

以核酸为检测靶向的分子诊断方法是传染性病原体检测的金标准，但将其应用于便携化或现场快速诊断时仍存在多种限制和挑战，如特异性差、操作繁琐和便携化难等。规律间隔成簇短回文重复序列（CRISPR）/CRISPR相关蛋白（Cas）-荧光检测... 详细信息

以核酸为检测靶向的分子诊断方法是传染性病原体检测的金标准，但将其应用于便携化或现场快速诊断时仍存在多种限制和挑战，如特异性差、操作繁琐和便携化难等。规律间隔成簇短回文重复序列（CRISPR）/CRISPR相关蛋白（Cas）-荧光检测方法有望大幅提升核酸识别的特异性和信噪比。本研究开发了环介导等温扩增（LAMP）-CRISPR/Cas-便携化灰度读取仪检测系统。在CRISPR RNA (crRNA)存在下，利用CRISPR/Cas12a体系实现了对自主设计的甲型和乙型流感病毒核酸LAMP扩增反应体系的精准荧光检测，验证了CRISPR/Cas体系的高选择性和通用性。配套自主开发的便携化灰度读取仪，可同时实现荧光信号的低成本采集和高可靠性可视化判读，检测结束后直接输出样品的阳/阴性结果。利用本检测系统对实际样本进行了分析，验证了其可靠性和实用性，证明了本系统能够实现流感病毒的高灵敏、高特异性便携化分析。

关键词：等温扩增 CRISPR-Cas 荧光便携化检测流行性病原灰度读取仪

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经济不安全感对大学生心理健康的影响研究

岳阳职业技术学院学报 2024年第3期39卷 77-82页

作者：刘晨怡余芬戴朝晖岳阳职业技术学院学生工作处湖南岳阳414000 岳阳职业技术学院教育督导与质量评价处湖南岳阳414000 岳阳职业技术学院科研处湖南岳阳414000

目的考察经济不安全感对大学生心理健康水平的影响。方法采用Schwarz等人编制的经济不安全感量表和***编制的90项问卷清单(SCL-90)对7391名在校大学生的经济不安全感和心理健康水平进行调查。结果对调查数据进行描述性统计和独立样本... 详细信息

目的考察经济不安全感对大学生心理健康水平的影响。方法采用Schwarz等人编制的经济不安全感量表和***编制的90项问卷清单(SCL-90)对7391名在校大学生的经济不安全感和心理健康水平进行调查。结果对调查数据进行描述性统计和独立样本t检验结果表明,在经济不安全感上的得分男性显著高于女性,在SCL-90总均分和阳性项目数上男性均显著高于女性。通过回归分析发现经济不安全感可以显著正向预测SCL-90的总均分,加入性别和年龄作为调节变量后,经济不安全感依旧可以显著正向预测SCL-90的总均分。结论男大学生的心理健康水平和经济不安全感程度低于女大学生,经济不安全感会影响大学生的心理健康水平,经济不安全感程度越高,心理健康水平越低。

关键词：经济不安全感大学生心理健康水平

Evaluation of water management on arsenic methylation and volatilization in arsenic-contaminated soils strengthened by bioaugmentation and biostimulation

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Journal of Environmental Sciences 2024年第3期137卷 515-526页

作者： Peng chen yi liu Guo-Xin Sun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China

Arsenic(As) fate in paddy fields has been one of the most significant current issues due to the strong As accumulation potential of rice plants under fooded conditions. However,no attempt was done to explore As methylation and volatilization under non-fooded conditions. Herein, we investigated the effects of water management on As methylation and volatilization in three arsenic-contaminated soils enhanced by biostimulation with strawderived organic matter and bioaugmentation with genetic engineered Pseudomonas putida KT2440(GE P. putida). Under fooded conditions, the application of biochar(BC), rice straw(RS)and their combination(BC+RS) increased total As in porewater. However, these effects were greatly attenuated under non-fooded conditions. Compared with RS amendment alone, the combination of GE P. putida and RS further promoted the As methylation and volatilization,and the promotion percentage under non-fooded conditions were significantly higher than that under fooded conditions. The combined GE P. putida and RS showed the highest efficiency in As methylation(88 μg/L) and volatilization(415.4 μg/(kg·year)) in the non-fooded soil with moderate As contamination. Finally, stepwise multiple linear regression analysis presented that methylated As, DOC and p H in porewater were the most important factors contributing to As volatilization. Overall, our findings suggest that combination of bioaugmentation with GE P. putida and biostimulation with RS/BC+RS is a potential strategy for bioremediation of arsenic-contaminated soils by enhancing As methylation and volatilization under non-fooded conditions.

关键词： Arsenic methylation Arsenic volatilization Water management Straw incorporation Bioaugmentation

Hematite-facilitated microbial ammoxidation for enhanced nitrogen removal in constructed wetlands

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 35-45页

作者： Hao Qin Wenbo Nie Duo yi Dongxu Yang Mengli chen Tao liu yi chen Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment(Ministry of Education) Chongqing UniversityChongqing 400045China College of Environment and Ecology Chongqing UniversityChongqing 400045China Faculty of Geosciences and Environmental Engineering Southwest Jiaotong UniversityChengdu 610031China

Constructed wetlands(CWs)are widely applied for decentralized wastewater ***,achieving efficient removal of ammonia(NH+-N)has proven challenging due to insufficient *** this study,natural hematite(Fe,O3)was employed as a CW substrate(H-CWs)for the first time to drive anaerobic ammonia oxidation coupled with iron(I)reduction(Feammox).Compared to gravel constructed wetlands(G-CWs),ammonia removal was enhanced by 38.14%to 54.03%and nitrous oxide(N_(2)0)emissions were reduced by 34.60%in *** synergistic removal of ammonia and nitrate by H-CWs also resulted in the absence of ammoxidation *** and 15N isotope tracer incubations showed that Feammox accounting for approximately 40%of all ammonia removal in the *** enrichment of iron phosphate(Fe_(3)Fe_(4)(PO_(4))_(6))promoted the accumulation of the Feammox intermediate compound *** nanowires were observed on the surface of H-CW substrates as well,suggesting that the observed biological ammoxidation was most likely related to extracellular electron transfer(EET).Microbial and metagenomics analysis revealed that H-CWs elevated the integrity and enhanced the abundance of functional microorganisms and genes associated with nitrogen ***,the efficient ammonia removal in the absence of O2 together with a reduction in N_(2)O emissions as described in this study may provide useful guidance for hematite-mediated anaerobic ammonia removal in CWs.

关键词： Constructed wetlands Nitrogen removal Feammox Hematite Iron cycle

Atomistic study on the microscopic mechanism of grain boundary embrittlement induced by small dense helium bubbles in iron

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Nuclear Science and Techniques 2024年第3期35卷 84-95页

作者： Lei Peng Yong-Jie Sun Jing-yi Shi yi-Fei liu Shang-Ming chen liu-liu Li State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

The helium bubbles induced by 14 MeV neutron irradiation can cause intergranular fractures in reduced activation ferritic martensitic steel,which is a candidate structural material for fusion *** order to elucidate the susceptibility of different grain boundaries(GBs)to helium-induced embrittlement,the tensile fracture processes of 10 types of GBs with and without helium bubbles in body-centered cubic(bcc)iron at the relevant service temperature of 600 K were investigated via molecular dynamics *** results indicate that in the absence of helium bubbles,the GBs studied here can be classified into two distinct categories:brittle GBs and ductile *** atomic scale analysis shows that the plastic deformation of ductile GB at high temperatures originates from complex plastic deformation mechanisms,including the Bain/Burgers path phase transition and deformation twinning,in which the Bain path phase transition is the most dominant plastic deformation ***,the presence of helium bubbles severely inhibits the plastic deformation channels of the GBs,resulting in a significant decrease in elongation at *** bubble-decorated GBs,the ultimate tensile strength increases with the increase in the misorientation ***,the coherent twin boundary∑3{112}was found to maintain relatively high fracture strength and maximum failure strain under the influence of helium bubbles.

关键词： Helium bubble Grain boundary Embrittlement Reduced activation ferritic martensitic steel Molecular dynamics Bain path

Experimental investigation of engineered geopolymer composite for structural strengthening against blast loads

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Defence Technology（防务技术） 2024年第2期32卷 496-509页

作者： Shan liu Chunyuan liu yifei Hao yi Zhang Li chen Zhan Li Key Laboratory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Prefabricated Buildings and Intelligent Construction Hebei University of TechnologyTianjin 300400China Institute of Defense Engineering AMSPLABeijing 100850China Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189JiangsuChina State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of the PLANanjing 210007JiangsuChina

The recent increase in blast/bombing incidents all over the world has pushed the development of effective strengthening approaches to enhance the blast resistance of existing civil *** geopolymer composite(EGC)is a promising material featured by eco-friendly,fast-setting and strain-hardening characteristics for emergent strengthening and ***,the fiber optimization for preparing EGC and its protective effect on structural elements under blast scenarios are *** this study,laboratory tests were firstly conducted to evaluate the effects of fiber types on the properties of EGC in terms of workability,dry shrinkage,and mechanical properties in compression,tension and *** experimental results showed that EGC containing PE fiber exhibited suitable workability,acceptable dry shrinkage and superior mechanical properties compared with other types of *** that,a series of field tests were carried out to evaluate the effectiveness of EGC retrofitting layer on the enhancement of blast performance of typical *** tests include autoclaved aerated concrete(AAC)masonry walls subjected to vented gas explosion,reinforced AAC panels subjected to TNT explosion and plain concrete slabs subjected to contact *** was found that EGC could effectively enhance the blast resistance of structural elements in different *** AAC masonry walls and panels,with the existence of EGC,the integrity of specimens could be maintained,and their deflections and damage were significantly *** plain concrete slabs,the EGC overlay could reduce the diameter and depth of the crater and spallation of specimens.

关键词： Engineered geopolymer composites Fiber optimization Strengthening material Blast resistance Masonry wall Reinforced AAC panel Plain concrete slab

Photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na

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Science China Chemistry 2024年第2期67卷 587-594页

作者： Fangming chen Lvqi Jiang Chunyang Hu Jie liu Wenbin yi School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory of Organofluorine Chemistry Shanghai Institute Organic ChemistryChinese Academy of SciencesShanghai200032China

Since the first report of sodium trifluoromethanesulfinate(CF_(3)SO_(2)Na) as an electrophilic trifluoromethylthiolation reagent in 2015,there has been no breakthrough in research in this ***,we disclose an unprecedented usage of CF_(3)SO_(2)Na as a radical trifluoromethylthiolation reagent.A photocatalyzed ditrifluoromethylthiolation of alkenes with CF_(3)SO_(2)Na in the presence of PPh_(3) and catalytic copper has been ***,either Ir[(p-Fppy)_(2)(bpy)]PF_6 or Ir(ppy)_(3) could facilitate this *** studies indicate that initiation of the radical chain proceeded via two different photocatalytic quenching *** protocol provides a practical method for the construction of diverse vicinal ditrifluoromethylthiolated compounds.

关键词： trifluoromethylthiolation photocatalysis radical difunctionalization alkenes

Outlier-resistant distributed fusion filtering for nonlinear discrete-time singular systems under a dynamic event-triggered scheme

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 237-249页

作者： Zhibin HU Jun HU Cai chen Hongjian liu Xiaojian yi Department of Applied Mathematics Harbin University of Science and TechnologyHarbin150080China Heilongjiang Provincial Key Laboratory of Optimization Control and Intelligent Analysis for Complex Systems Harbin University of Science and TechnologyHarbin150080China School of Automation Harbin University of Science and TechnologyHarbin150080China School of Mathematics and Physics Anhui Polytechnic UniversityWuhu241000China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing314003China Tangshan Research Institute Beijing Institute of TechnologyTangshan063099China

This paper investigates the problem of outlier-resistant distributed fusion filtering(DFF)for a class of multi-sensor nonlinear singular systems(MSNSSs)under a dynamic event-triggered scheme(DETS).To relieve the effect of measurement outliers in data transmission,a self-adaptive saturation function is ***,to further reduce the energy consumption of each sensor node and improve the efficiency of resource utilization,a DETS is adopted to regulate the frequency of data *** the addressed MSNSSs,our purpose is to construct the local outlier-resistant filter under the effects of the measurement outliers and the DETS;the local upper bound(UB)on the filtering error covariance(FEC)is derived by solving the difference equations and minimized by designing proper filter ***,according to the local filters and their UBs,a DFF algorithm is presented in terms of the inverse covariance intersection fusion *** such,the proposed DFF algorithm has the advantages of reducing the frequency of data transmission and the impact of measurement outliers,thereby improving the estimation ***,the uniform boundedness of the filtering error is discussed and a corresponding sufficient condition is ***,the validity of the developed algorithm is checked using a simulation example.

关键词： Distributed fusion filtering Multi-sensor nonlinear singular systems Dynamic event-triggered scheme Outlier-resistant filter Uniform boundedness