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Journal of Environmental Sciences 2024年第3期137卷 347-357页

作者： Tengda Shi Ruijing Li Jie Fu Chao Hou Hui Gao Guanjie Cheng Haibo Zhang Shuaichen Jin Liang Kong Guangshui Na College of Marine Technology and Environment Dalian Ocean UniversityDalian 116023China Laboratory for coastal marine eco-environment process and carbon sink of Hainan province/Yazhou Bay Innovation Institute Hainan Tropical Ocean UniversitySanya 572022China National Marine Environmental Monitoring Center Dalian 116023China College of Marine Ecology and Environment Shanghai Ocean UniversityShanghai 201306China NCS Testing Technology Co. Ltd.Beijing 10081China

Eleven organophosphate esters(OPEs)in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific *** concentration of total OPEs ranged from 164.82 to 3501.79 pg/m~3in air and from 4.54 to 70.09 ng/L in *** halogenated OPEs,tri(chloropropyl)phosphate(TCPP)and tri(2-chloroethyl)phosphate(TCEP),were generally more abundant than the non-halogenated OPEs.A levelⅢfugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross *** model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer,during which the Ross Sea acts as a final OPE *** and wet deposition dominated the processes involving OPE transfer to *** OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater *** findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic.

关键词： Organophosphate esters(OPEs) Long-range transport Fugacity model Antarctic fate

A CFD study of the transport and fate of airborne droplets in a ventilated office:The role of droplet−droplet interactions

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Frontiers of Environmental Science & Engineering 2022年第3期16卷 49-62页

作者： Allan Gomez-Flores Gukhwa Hwang Sadia Ilyas Hyunjung Kim Department of Environment and Energy Jeonbuk National UniversityJeonju Jeonbuk 54896Republic of Korea Department of Mineral Resources and Energy Engineering Jeonbuk National UniversityJeonju Jeonbuk 54896Republic of Korea

Previous studies reported that specially designed ventilation systems provide good air quality and safe environment by removing airborne droplets that contain viruses expelled by infected *** water droplets can be stable in the environment and remain suspended in air for prolonged *** between droplets may occur and droplet interactions should be ***,the previous studies focused on other physical phenomena(air flow,drag force,evaporation)for droplet transport and neglected droplet *** this work,we used computational fluid dynamics(CFD)to simulate the transport and fate of airborne droplets expelled by an asymptomatic person and considered droplet *** drag with turbulence for prediction of transport and fate of droplets indicated that the turbulence increased the transport of 1μm droplets,whereas it decreased the transport of 50μm *** contrast to only considering drag and turbulence,consideration of droplet interactions tended to increase both the transport and *** the length scale of the office is much larger than the droplet sizes,the droplet interactions,which occurred at the initial stages of release when droplet separation distances were shorter,had a significant effect in droplet fate by considerably manipulating the final locations on surfaces where droplets ***,it is proposed that when an exact prediction of transport and fate is required,especially for high droplet concentrations,the effects of droplet interactions should not be ignored.

关键词： Droplet interactions Aerosols Colloids CFD Transport fate

Environmental fate and behavior of silver nanoparticles in natural estuarine systems

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Journal of Environmental Sciences 2020年第2期32卷 248-259页

作者： Penghui Li Min Su Xiaodan Wang Xiaoyan Zou Xia Sun Junpeng Shi Hongwu Zhang Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Silver nanoparticles(AgNPs) are widely used in many consumer products, whereas their environmental behaviors in natural aquatic systems remain unknown, especially in natural brackish ***, it is urgent to investigate the environmental fate of AgNPs in natural brackish ***, we investigated the stability of citrate-coated AgNPs in natural brackish water collected from 6 different sites with distinct salinities in the Xinglinwan Reservoir, located in Xiamen City, southeast *** obtained results showed that AgNP colloids remained stable in low-salinity waters, which was mainly determined by the effects of dissolved organic matter(DOM) promoting the stability of the ***, the environmental fate of AgNPs in high-salinity waters was dominated by the salinity or ionic strength, especially the free ion concentrations of Cl-, SO42-, or S2-, resulting in rapid sedimentation and *** addition, both DOM and salinity contributed to the environmental behavior of AgNPs in moderate-salinity waters,ultimately resulting in either colloidal stability or ***, these results may reveal that AgNPs remain relatively stable for a long period in low-salinity natural waters,and that the stability might gradually decrease as AgNPs are transferred from freshwaters through brackish waters and eventually end up in seawater along the *** findings also further indicate that the toxicity and potential risks of AgNPs may present more serious threats to the environment and organisms in natural freshwaters than in natural estuarine systems or seawater.

关键词： Silver nanoparticles Salinity Dissolved organic matter Environmental fate Potential toxicity Natural brackish system

An investigation of the fate and behaviour of a mixture of WO_3 and TiO_2 nanoparticles in a wastewater treatment plant

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Journal of Environmental Sciences 2019年第2期31卷 37-47页

作者： Sandile Simelane Langelihle Nsikayezwe Dlamini Department of Applied Chemistry University of JohannesburgDoornfontein Campus

The fate and behaviour of WO_3 and TiO_2 mixture were investigated following the Organisation for Economic Co-operation and Development 303 A guidelines. The nanoparticles were found not to influence the chemical oxygen demand removal efficiency which was maintained >80%hence the activated sludge process was on affected. The nanoparticles were eliminated from the wastewater with a greater percentage of 99.8% for TiO_2 and 95.5% for WO_3 found in the *** activated sludge process also had no effect of the polymorphs of the nanoparticles as X-ray diffraction revealed presence of monoclinic WO_3 and anatase TiO_2 which were spiked into the influent. The nanoparticles were mainly removed by bio-adsorption on the activated sludge surface. The total plate count revealed that the bacterial colonies present in the control and the test units were comparable during the gradual introduction of nanoparticles in the *** biomass was >0.75 MLVSS/MLSS(mixed liquor volatile suspended solids/mixed liquor suspended solids) in both the aeration vessels thus a greater proportion of the sludge were the microorganisms. A greater percentage of the Ti and W found in the effluent was mainly due to the nanoparticles adsorbed on the suspended solids with only 3.6% Ti and 28.6% W due to dissolution of nanoparticles.

关键词： fate Functionality Tungsten trioxide Titanium dioxide nanoparticles Wastewater Dissolution

Sialylation is involved in cell fate decision during development, reprogramming and cancer progression

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Protein & Cell 2019年第8期10卷 550-565页

作者： Fenjie Li Junjun Ding Program in Stem Cell and Regenerative Medicine The Third Affiliated Hospital of Sun Yat-Sen University Zhongshan School of Medicine Sun Yat-Sen University Guangzhou China Key Laboratory for Stem Cells and Tissue Engineering Ministry of Education Department of Cell Biology Zhongshan School of Medicine Sun Yat-Sen University Guangzhou China

Sialylation, or the covalent addition of sialic acid to the terminal end of glycoproteins, is a biologically important modification that is involved in embryonic development, neurodevelopment, reprogramming, oncogenesis and immune responses. In this review, we have given a comprehensive overview of the current literature on the involvement of sialylation in cell fate decision during development, reprogramming and cancer progressionSialylation is essential for early embryonic development and the deletion of UDP-GIcNAc 2-epimerase, a rate-limiting enzyme in sialic acid biosynthesis, is embryonically lethal. Furthermore, the sialyltransferase ST6GAL1 is required for somatic cell reprogramming, and its downregulation is associated with decreased reprogramming efficiency. In addition, sialylation levels and patterns are altered during cancer progression, indicating the potential of sialylated molecules as cancer biomarkers. Taken together, the current evidences demonstrate that sialylation is involved in crucial cell fate decision.

关键词： sialylation cell fate development reprogramming cancer

Orchestrating stem cell fate: Novel tools for regenerative medicine

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World Journal of Stem Cells 2019年第8期11卷 464-475页

作者： Sara Cruciani Sara Santaniello Andrea Montella Carlo Ventura Margherita Maioli Department of Biomedical Sciences University of Sassari Sassari 07100 Italy Laboratory of Molecular Biology and Stem Cell Engineering National Institute of Biostructures and Biosystems – Eldor Lab Innovation Accelerator Consiglio Nazionale delle Ricerche Bologna 40129 Italy Operative Unit of Clinical Genetics and Developmental Biology Sassari 07100 Italy Istituto di Ricerca Genetica e Biomedica Consiglio Nazionale delle Ricerche Cagliari 09042 Italy Center for Developmental Biology and Reprogramming-CEDEBIOR Department of Biomedical Sciences University of Sassari Sassari 07100 Italy

Mesenchymal stem cells are undifferentiated cells able to acquire different phenotypes under specific stimuli. In vitro manipulation of these cells is focused on understanding stem cell behavior, proliferation and pluripotency. Latest advances in the field of stem cells concern epigenetics and its role in maintaining self-renewal and differentiation capabilities. Chemical and physical stimuli can modulate cell commitment, acting on gene expression of Oct-4, Sox-2 and Nanog, the main stemness markers, and tissue-lineage specific genes. This activation or repression is related to the activity of chromatin-remodeling factors and epigenetic regulators, new targets of many cell therapies. The aim of this review is to afford a view of the current state of in vitro and in vivo stem cell applications, highlighting the strategies used to influence stem cell commitment for current and future cell therapies. Identifying the molecular mechanisms controlling stem cell fate could open up novel strategies for tissue repairing processes and other clinical applications.

关键词： Stem cells Epigenetics Self-renewal In vitro differentiation Physical stimuli Stem cell fate Clinical practice Cell transplantation

Small molecules for mesenchymal stem cell fate determination

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World Journal of Stem Cells 2019年第12期11卷 1084-1103页

作者： Yu-Hao Cheng Jing-Cheng Dong Qin Bian Institute for Cell Engineering Johns Hopkins University School of MedicineBaltimoreMD 21205United States Department of Integrative Medicine Huashan HospitalFudan UniversityShanghai 200040China

Mesenchymal stem cells(MSCs)are adult stem cells harboring self-renewal and multilineage differentiation potential that are capable of differentiating into osteoblasts,adipocytes,or chondrocytes in vitro,and regulating the bone marrow microenvironment and adipose tissue remodeling in *** process of fate determination is initiated by signaling molecules that drive MSCs into a specific *** of MSC fate determination leads to different bone and adipose tissue-related diseases,including aging,osteoporosis,and insulin *** progress has been made in recent years in discovering small molecules and their underlying mechanisms control the cell fate of MSCs both in vitro and in *** this review,we summarize recent findings in applying small molecules to the trilineage commitment of MSCs,for instance,genistein,medicarpin,and icariin for the osteogenic cell fate commitment;isorhamnetin,risedronate,and arctigenin for pro-adipogenesis;and atractylenolides and dihydroartemisinin for chondrogenic fate *** highlight the underlying mechanisms,including direct regulation,epigenetic modification,and post-translational modification of signaling molecules in the AMPK,MAPK,Notch,PI3K/AKT,Hedgehog signaling pathways *** discuss the small molecules that are currently being studied in clinical *** target-based manipulation of lineage-specific commitment by small molecules offers substantial insights into bone marrow microenvironment regulation,adipose tissue homeostasis,and therapeutic strategies for MSC-related diseases.

关键词： Mesenchymal stem cell Mesenchymal stromal cell Cell fate determination Small molecules Natural compounds Signaling pathways

基于fate实现的联邦学习在大数据环境下的隐私应用

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基于FATE实现的联邦学习在大数据环境下的隐私应用

作者：关泽宇西北大学

学位级别：硕士

多源数据的机器学习模型一直是人工智能领域的热门话题。一方面,机器学习的模型效果优劣与数据规模的大小程度极大相关,另一方面在真实实践中,能够用于同一模型的数据往往处于不同数据方。传统解决多源数据建模的方式是直接将数据放在... 详细信息

多源数据的机器学习模型一直是人工智能领域的热门话题。一方面,机器学习的模型效果优劣与数据规模的大小程度极大相关,另一方面在真实实践中,能够用于同一模型的数据往往处于不同数据方。传统解决多源数据建模的方式是直接将数据放在单方共同建模,这种方法没有考虑隐私性。在社会隐私意识提升,法律法规完善的当下,直接数据交易面临法律和舆论的双重压力,形成“数据孤岛”问题。联邦学习（Federated Learning）是解决多方数据安全联合建模的重要手段,能够对抗恶意攻击的联邦学习算法也是一个比较热的联邦学习研究领域。联邦学习在安防,金融,零售中已有应用落地,在医疗领域的应用是一个比较热的研究领域,在其他更多领域也在拓展中。联邦学习正在对越来越多的机器学习算法提供支持。除了经典的逻辑回归、决策树,近年来深度神经网络在联邦学习的应用越来越多,Google还提出了Split learning对基于深度神经网络的联邦学习的拓展。微众银行的开源项目fate是国内第一个工业可用的联邦学习开源平台。fate解决安全隐私问题的手段是多方面的,集成了包括安全多方计算、可信执行环境等方式。fate的数据通信框架可以保证梯度交互对外的安全性,但隐私方面仍存在两方面的问题:安全方面对成员攻击、梯度攻击等方式没有提供很好的保护;效率方面,基于原数据库版本的fate对大数据场景的支持不佳。本文针对fate存在的问题,将差分隐私技术引入联邦学习框架中。通过搭建开源框架、改进client端差分联邦学习算法、基于真实公开数据集实验、定量结果分析的步骤,在确保模型精度的情况下,实现提高安全性能的目的。主要创新点如下:1.利用高斯机制实现在客户端加入噪声,针对原fate联邦学习无损交互可能会导致成员攻击泄露梯度的问题,提出联邦DP算法。在模型精度降低可接受的范围内,提高隐私保护程度。2.基于fate on Spark实现算法,使用spark组件提高了运算效率,使联邦学习的统计学结果泛用性增强。3.由于隐私保护程度和模型性能不能兼顾,实验从参数角度对添加噪声的强度和模型可用性的关系进行了讨论,有利于模型建构中定量权衡隐私和精度的关系。将两者结合考虑更具有实际意义。

关键词：联邦学习差分隐私大数据 fate spark

A review of sources,fate,levels,toxicity,exposure and transformations of organophosphorus flame-retardants and plasticizers in the environment

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Emerging Contaminants 2020年第1期6卷 345-366页

作者： Tlou B.Chokwe Ovokeroye A.Abafe Senzy P.Mbelu Jonathan O.Okonkwo Linda L.Sibali Scientific Services Unit Capricorn District Municipality24 Thabo Mbeki StreetPolokwane0699South Africa Department of Environmental Sciences University of South AfricaChristaan de Wet RoadFlorida1709South Africa Onderstepoort Veterinary Research Agricultural Research Council100 Old Soutpan RoadOnderstepoortPretoria0110South Africa Scientific Services Rand Water2 Barrage RoadVereeniging1930South Africa Department of Water Environmental and Earth SciencesTshwane University of Technology75 Mandela DrivePretoria0001South Africa

Organophosphate esters(OPEs)are esters of phosphoric acid that are increasingly used as plasticizers and by the flame-retardants industries as replacement for the regulated polybrominated diphenyl *** most commonly classes of these pollutants are the chlorinated-and *** extent and magnitude of OPEs occurrence in the environment,combined with striking structural similarities to toxic organophosphorus pesticides has led to public concern over risk posed by these *** peer-reviewed literature published from the last decade(2010e2019),concentrations and distributions of commonly studied OPEs based on their occurrence in different matrices around the globe were evaluated and *** pollutants have a wide range of physicochemical properties such as their water solubility’s,logKow value,vapour pressure and bioconcentration factors(BCFs)which are very important factors in assessing their behaviour in different environmental *** progress in research on OPEs over the years,full understanding of the environmental behaviour and fate of these pollutants are still *** by which these pollutants enter the environment in conjunction with their concentrations together with their toxicities,estimated daily intakes,transformation products and fates are *** is envisaged that this review will heighten the importance of identifying emerging issues,data gaps and provide a future research agenda for OPEs.

关键词： Organophosphorus compounds Concentrations Sources fate Toxicity Estimated daily intakes

An Analysis of Pecola's Tragic fate in The Bluest Eye

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海外英语 2012年第14期 200-201页

作者：周叶函云南大学云南昆明650091

In The Bluest Eye,the author narrates a little black girl's strong desire to have blue *** last,Pecola imagines possessing blue eyes at the cost of going *** paper mainly argues that it is the family's influence,the i... 详细信息

关键词： Pecola’s tragic fate family’s influence internaliz