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Implementing Routine HIV Screening in Hospitals:An Effective Practice to Expand HIV Testing—Xishuangbanna Prefecture,Yunnan Province,China,2019–2020

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China CDC weekly 2023年第13期5卷 283-286页

作者： Yidan Wang Yanling Ma Qiyu Zhu wenyue xu Haolan Sun Dongmin Li Cong Jin National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Yunnan Center for Disease Control and Prevention Kunming CityYunnan ProvinceChina Xishuangbanna Center for Disease Control and Prevention Xishuangbanna PrefectureYunnan ProvinceChina School of Chemistry and Molecular Biosciences University of QueenslandSt LuciaAustralia

Summary What is already known about this topic?Research evidence is insufficient to suggest whether routine human immunodeficiency virus(HIV)screening in healthcare settings is effective in promoting greater awareness of HIV-positive status.What is added by this report?This study found that,following the implementation of routine HIV screening in hospitals in Xishuangbanna Prefecture,Yunnan Province,there was a significant increase in the number of HIV screenings,positive results,and the positive rate of HIV screening in primary-level hospitals.What are the implications for public health practice?Routine hospital-based HIV screening is effective in identifying HIV infections in areas with concentrated epidemics.

关键词： routine Prefecture identifying

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing Liu Bing xu Zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by humans.To understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were investigated.These rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global average.The δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,respectively.The end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate gradients.Multiple isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid environment.Based on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely exposed.While the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier environment.Besides,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

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基于GAN-DCNN的树叶识别

林业科学 2024年第4期60卷 40-51页

作者：徐竞怡张志闫飞张雯悦北京林业大学精准林业北京市重点实验室北京100083 中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室北京100101 中国科学院大学北京101408 商汤科技研究院北京100039

【目的】利用深度学习进行树叶识别时需要大量训练样本,当样本量不足、图像风格单一会导致识别准确率不稳定。研究利用少量的样本进行树叶图像增殖和风格转换,可极大减轻数据采集的负担,为提升林业调查信息化、智能化提供有效的技术手... 详细信息

【目的】利用深度学习进行树叶识别时需要大量训练样本,当样本量不足、图像风格单一会导致识别准确率不稳定。研究利用少量的样本进行树叶图像增殖和风格转换,可极大减轻数据采集的负担,为提升林业调查信息化、智能化提供有效的技术手段和理论支撑。【方法】采集6种树种的树叶图像建立数据集,引入light-weight GAN对图像进行增殖和风格转换,扩充人工拍摄的树叶数据集,通过在该数据集与原数据集上分别应用AlexNet、GoogLeNet、ResNet34和ShuffleNetV2四种深度卷积神经网络进行训练,分析生成对抗网络的图像增殖技术在树叶识别中的作用。综合模型准确率和训练时间等性能指标选择最优模型,同时对模型的学习率进行调整。使用测试样本对参数优化后的模型进行验证,分析该方法在实践中的可行性和意义。【结果】基于生成对抗网络生成的样本具有高清晰度,高保真性,能够有效地辅助神经网络模型的训练工作,同时也丰富了样本类别,使之获得包含更多不同季节、形状、健康状况的树叶图像。与原始数据集相比,AlexNet、GoogLeNet、ResNet34和ShuffleNetV2四种网络在新数据集的训练上均表现出训练误差更小、验证精度更高的特点,其中学习率为0.01的ShuffleNetV2模型对该数据集的训练效果最好,训练时最高验证精度为99.7%。使用未参与训练的测试样本对该模型进行验证,模型对各树叶的识别效果较好,模型的总体识别准确率高达99.8%。与未使用GAN技术的普通深度卷积神经网络相比,本文提出的模型对树叶识别准确率明显提升。【结论】生成对抗网络可以有效地扩充图像数量,对图像进行风格转换,与深度卷积神经网络相结合,可以显著提高树叶识别准确率,适合应用于林业树叶识别领域。

关键词：树叶识别生成对抗网络深度卷积神经网络

野生动物栖息地连通性与通道选址研究——以广州市为例

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热带地理 2024年第7期44卷 1289-1299页

作者：杨文越徐子豪华南农业大学林学与风景园林学院广州510642

道路基础设施建设的扩张导致野生动物栖息地的严重破碎化。开展野生动物栖息地连通性分析并识别野生动物通道选址,对于区域生态修复和栖息地保护具有重要意义。文章以广州市作为研究区域,结合生境适宜性模型、形态空间格局分析(MSPA)和... 详细信息

道路基础设施建设的扩张导致野生动物栖息地的严重破碎化。开展野生动物栖息地连通性分析并识别野生动物通道选址,对于区域生态修复和栖息地保护具有重要意义。文章以广州市作为研究区域,结合生境适宜性模型、形态空间格局分析(MSPA)和景观连通性指数识别和分析野生动物栖息地。同时,使用水文分析方法提取野生动物扩散路径,识别野生动物通道选址位置。结果表明:1)广州市野生动物栖息地面积和数量较低,呈“东北集聚、中西分散”的分布格局,栖息地内部生态功能相对稳定,但外部缺乏促进连通的小型生态空间;2)不同的栖息地斑块对于维持野生动物栖息地整体连通性发挥的作用具有显著差异。分别识别出关键斑块4处、重要斑块9处,它们是广州生态网络与栖息地保护的关键区域;3)道路基础设施对野生动物在栖息地间的扩散构成了严重的阻碍作用。共识别野生动物一级扩散路径221.94km,二级扩散路径84.09km,以及这些路径与高、快速路交汇的一级野生动物通道38处、二级通道13处。野生动物通道的建设可有效保障区域生态网络的完整性和整体连通性,对于维护生物多样性和生态系统稳定性具有重要意义。

关键词：野生动物栖息地连通性道路基础设施野生动物通道生态保护与修复广州市

Biohythane production from two-stage anaerobic digestion of food waste:A review

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Journal of Environmental Sciences 2024年第5期139卷 334-349页

作者： Xiaona An Ying xu Xiaohu Dai State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

The biotransformation of food waste(FW)to bioenergy has attracted considerable research attention as a means to address the energy crisis and waste disposal problems.To this end,a promising technique is two-stage anaerobic digestion(TSAD),in which the FW is transformed to biohythane,a gaseous mixture of biomethane and biohydrogen.This review summarises the main characteristics of FW and describes the basic principle of TSAD.Moreover,the factors influencing the TSAD performance are identified,and an overview of the research status;economic aspects;and strategies such as pre-treatment,co-digestion,and regulation of microbial consortia to increase the biohythane yield from TSAD is provided.Additionally,the challenges and future considerations associated with the treatment of FW by TSAD are highlighted.This paper can provide valuable reference for the improvement and widespread implementation of TSAD-based FW treatment.

关键词： Two-stage anaerobic digestion(TSAD) Food waste(FW) Methane production Hydrogen production

Identification of high oxygen-consuming substances in stormwater drainage systems illicitly connected with sewage system

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Journal of Environmental Sciences 2024年第4期138卷 132-140页

作者： Chen xu Zuxin xu Wenhai Chu Shanshan Wu Rong Xiao Lei Su State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Ministry of Education Key Laboratory of Yangtze River Water Environment Tongji UniversityShanghai 200092China Guangzhou Resource Environmental Protection Technology Co. Ltd.Guangzhou 510030China

The dissolved oxygen content in water is an important indicator for assessing the quality of the water environment,and maintaining a certain amount of dissolved oxygen is essential for the healthy development of the ecological environment.When a water body is anoxic,the activity of anaerobic microorganisms increases and organic matter is decomposed to produce a large number of blackening and odorizing substances,resulting in black and odorous water bodies,which is a very common and typical phenomenon in China.Presently,there is still a relatively universal occurrence of illicitly connected stormwater and sewage pipes in the urban drainage pipe network in China,which makes oxygen-consuming substances be directly discharged into rivers through stormwater pipes and consume the dissolved oxygen in the water bodies,resulting in an oxygen deficiency of the water.This induces seasonal or year-round black and stink phenomena in urban rivers.Hence,identifying high oxygen-consuming substances,which lays the foundation for the subsequent removal of oxygen-consuming substances,is essential.Through a series of comparisons of water quality indicators and analysis of organic characteristics,it was found that the oxygen consumption capacity of domestic sewage was higher than that of industrial wastewater in the selected area of this study,and the oxygen-consuming substances of domestic sewage were small molecular amino acids.By comparing 20 conventional free amino acids,it was found that seven of them consumed oxygen easily,and compared with chemical oxygen consumption,biological oxygen consumption was in a leading position.

关键词： Urban drainage system Oxygen-consuming substances Domestic sewage Amino acid

Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu Hua Kuang Chuanlai xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health risks.In this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically investigated.Firstly,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was revealed.The DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of S-configuration.Meanwhile,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and dopamine.Thirdly,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

Mapping super-resolution image quality

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Light(Science & Applications) 2024年第2期13卷 178-180页

作者： Megan A.Steves Ke xu Department of Chemistry University of CaliforniaBerkeleyCA94720USA

The local quality of super-resolution microscopy images can be assessed and mapped by rolling Fourier ring correlation,even when image quality varies within a single image.

关键词： image resolution Mapping

Controllable chemical redox reactions to couple microbial degradation for organic contaminated sites remediation:A review

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Journal of Environmental Sciences 2024年第5期139卷 428-445页

作者： Bin Chen Jiang xu Lizhong Zhu College of Environmental and Resource Sciences Zhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control Zhejiang UniversityHangzhou 310058China Zhejiang Agriculture&Forest University Lin'an 311300China

Global environmental concern over organic contaminated sites has been progressively conspicuous during the process of urbanization and industrial restructuring.While traditional physical or chemical remediation technologies may significantly destroy the soil structure and function,coupling moderate chemical degradation with microbial remediation becomes a potential way for the green,economic,and efficient remediation of contaminated sites.Hence,this work systematically elucidates why and how to couple chemical technology with microbial remediation,mainly focused on the controllable redox reactions of organic contaminants.The rational design of materials structure,selective generation of reactive oxygen species,and estimation of degradation pathway are described for chemical oxidation.Meanwhile,current progress on efficient and selective reductions of organic contaminants(i.e.,dechlorination,defluorination,-NO_(2) reduction)is introduced.Combined with the microbial remediation of contaminated sites,several consideration factors of how to couple chemical and microbial remediation are proposed based on both fundamental and practical points of view.This review will advance the understanding and development of chemical-microbial coupled remediation for organic contaminated sites.

关键词： Soil remediation Groundwater remediation Rational design Reactive species Environmental nanotechnology