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Multistimuli-Responsive Luminescent Porous Organic Polymers with Chiroptical Properties and Acid-Induced Degradation

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Chinese Journal of Chemistry 2024年第16期42卷 1886-1894页

作者： Youling He dongyang fan Liang Zhang dong Wang Ting han Rongrong Hu Ben Zhong Tang Center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhenGuangdong 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhenGuangdong 518060China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong999077China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China Universityof TechnologyGuangzhouGuangdong 510640China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangdong 518172China

Porous organic polymers(POPs)have attracted great attention in past *** diverse functional POPs have been developed,multistimuli-responsive POPs with excellent aggregate-state luminescence together with good chiroptical properties have rarely been ***,two pairs of Salen-type enantiomeric PoPs with multistimuli-responsive luminescence and chiral features were designed and synthesized by facile polycondensation reactions between polyfunctional aggregation-induced emission luminogen(AlEgen)-containing salicylaldehyde derivatives and chiral *** Salen units in polymer backbones as tetradentate ligands,a series of POP-metal complexes were further *** obtained POPs and metal complexes show good porosity,high thermal stability,and obvious circular dichroism ***,benefiting from the coexistence of AlEgen and Salen units in polymer structures,these POPs exhibit excellent luminescence performance in aggregate states and tunable fluorescence behaviors in response to external stimuli of Zn^(2+)ion,mechanical forces,organic solvent,and *** to the dynamic feature of Schiff base C=N bonds,the present POPs can efficiently undergo hydrolysis reactions under strong acidic conditions to reproduce the AlEgencontaining monomers,and such an acid-induced degradation process can be directly visualized and dynamically monitored via fluorescence *** properties collectively make the POPs candidate materials for applications in heterogeneous asymmetric catalysis,fluorescence sensing,biomedicine,etc.

关键词： Polymers Stimuli-responsive luminescence Porous polymers Chirality Aggregation-induced emission Fluorescence Schiff bases Degradation

Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records

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Petroleum Science 2024年第2期21卷 1241-1256页

作者： Hui-Wen Pang han-Qing Wang Yi-Tian Xiao Yan Jin Yun-Hu Lu Yong-dong fan Zhen Nie National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China

Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network ***, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model.

关键词： Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records

Molecular signal networks and regulating mechanisms of the unfolded protein response

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第1期18卷 1-14页

作者： Jing GONG Xing-zhi WANG Tao WANG Jiao-jiao CHEN Xiao-yuan XIE Hui HU fang YU Hui-lin LIU Xing-yan JIANG han-dong fan Institute of Aging Research School of Medicine Hangzhou Normal University Hangzhou 310036 China Sichuan Radio and TV University Chengdu 610073 China The Third Affiliated Hospital Sun Yat-sen University Guangzhou 510630 China

Within the cell, several mechanisms exist to maintain homeostasis of the endoplasmic reticulum （ER）. One of the primary mechanisms is the unfolded protein response （UPR）. In this review, we primarily focus on the latest signal webs and regulation mechanisms of the UPR. The relationships among ER stress, apoptosis, and cancer are also discussed. Under the normal state, binding immunoglobulin protein （BiP） interacts with the three sensors （protein kinase RNA-like ER kinase （PERK）, activating transcription factor 6 （ATF6）, and inositol-requiring enzyme la （IREla）） Under ER stress, misfolded proteins interact with BiP, resulting in the release of BiP from the sensors. Subsequently, the three sensors dimerize and autophosphorylate to promote the signal cascades of ER stress. ER stress includes a series of positive and negative feedback signals, such as those regulating the stabilization of the sensors/BiP complex, activating and inactivating the sensors by autophosphorylation and dephosphorylation, activating specific transcription factors to enable selective transcription, and augmenting the ability to refold and export. Apart from the three basic pathways, vascular endothelial growth factor （VEGF）-VEGF receptor （VEGFR）-phospholipase C-~ （PLCy）-mammalian target of rapamycin complex 1 （mTORC1） pathway, induced only in solid tumors, can also activate ATF6 and PERK signal cascades, and IREla also can be activated by activated RAC-alpha serine/threonine-protein kinase （AKT）. A moderate UPR functions as a pro-survival signal to return the cell to its state of homeostasis. However, persistent ER stress will induce cells to undergo apoptosis in response to increasing reactive oxygen species （ROS）, Ca2＋ in the cytoplasmic matrix, and other apoptosis signal cascades, such as c-Jun N-terminal kinase （JNK）, signal transducer and activator of transcription 3 （STAT3）, and P38, when cellular damage exceeds the capacity of this adaptive response.

关键词： Unfolded protein response Endoplasmic reticulum (ER) stress Mechanism Signal networks Homeostasis

Recent progress in the deactivation mechanism of zeolite catalysts in methanol to olefins

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Science China Chemistry 2024年

作者： Sheng fan han Wang Sen Wang Mei dong Weibin fan State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Methanol to olefins(MTO) as an important reaction in C1 chemistry can effectively transform non-petroleum carbon resources into value-added chemicals. Zeolites have been widely used as MTO catalysts. However, they usually suffer from a rapid deactivation due to bulky coke species production, and thus require continuous regenerations in industrial application. The key to design and develop highly stable zeolite catalysts for MTO process is to unravel the deactivation mechanism and clarify the structure–performance relationship of catalysts. Here, in this mini-review, we investigate the critical intermediate species inducing zeolite deactivation and analyze the formation and evolution pathways of polycyclic aromatic hydrocarbons(PAHs)that are the precursors of carbonaceous deposits. In addition, some methods to alleviate the coking mainly including acid regulation, morphology modification and process optimization, are also summarized.

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Enhancing visible-light-driven NO oxidation through molecular‐level insights of dye-loaded sea sands

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Rare Metals 2024年第2期43卷 543-554页

作者： Yu-han Li Bang-Fu Chen Sónia A.C.Carabineiro You-Yu Duan Ping Tan Wing-Kei Ho fan dong Engineering Research Center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Key Laboratory of Catalysis and New Environmental MaterialsChongqing Technology and Business UniversityChongqing400067China Nanchang Institute of Technology Nanchang33044China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de Lisboa2829-516CaparicaPortugal College of Physics and Center of Quantum Materials and Devices Chongqing UniversityChongqing401331China Department of Science and Environmental Studies The Education University of Hong KongHong Kong999077China

Natural minerals,abundant and easily obtained through simple physical processing,offer a cost-effective and environmentally friendly solution for dyeing wastewater disposal and air pollution *** study investigates the photocatalytic removal of NO using natural different types of dyes,loaded on natural sand,under visible light *** examining various coating concentrations of dyes and sand weights,we discovered that sand loaded with Rhodamine B(RhB)exhibits high activity for the photo-oxidation of NO.A combination results of X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Fourier transform infrared spectroscopy(FTIR)and thermogravimetric(TG)analyses confirm the presence of SiO_(2),CaCO_(3),Al_(2)O_(3)and iron oxides as the main components of the ***,studying RhB-loaded individual components reveals that CaCO_(3)plays a crucial role in enhancing the NO removal *** results and theoretical calculations demonstrate the establishment of a directional charge transfer channel from CaCO_(3)to RhB,facilitating the adsorption and activation of molecular NO and O_(2).This work not only promotes the utilization of natural mineral resources but also enriches the fields of environmental photochemistry and semiconductor photocatalysis.

关键词： Sand dyes Rhodamine B Photo-oxidation of NO Visible light illumination

Eurasian otters prefer to prey on religious released nonnative fish on the Qinghai-Tibetan Plateau

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Current Zoology 2024年第4期70卷 472-479页

作者： Qiaoyun Wang Xuesong han Zichen Wang Kaidan Zheng Zhengyi dong Peng Zhang Pengfei fan Lu Zhang School of Life Sciences Sun Yat-Sen UniversityGuangzhou 510275China State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou 510275China School of Life Sciences Peking UniversityBeijing 100871China Shan Shui Conservation Center Beijing100871China School of Ecology Sun Yat-sen UniversityShenzhenGuangdong 518107China

Religious wildlife release is prevalent worldwide,especially in Asia *** is one of the anthropogenic pathways to cause biological *** fish release is common on the Qinghai-Tibetan Plateau,yet few studies have assessed the influences of religious fish release on local ***,a city on the Qinghai-Tibetan Plateau,we interviewedlocal people,conducted fish trap surveys in local rivers,and exam-ined the diet of Eurasian otters Lutra lutra using a fecal DNA metabarcoding *** found that fish release started at least in 1980-1990s in *** residents released fish in large amounts and released fish were usually exotic commercial fish purchased from *** such long-term and intensive fish release activities,released fish were few in local *** the other hand,Eurasian otters mainly prey on fish and released fish accounted for~20%of relative read abundance of prey DNA in otters'diet,indicating their high preference on released *** study suggested that religious fish release may provide additional food resources for otters,whereas otters,as a top predator in local rivers,may deplete non-native fish once they were released and,therefore,reduce the probability of colonization of released fish,although further studies are required to assess otters'*** study revealed otters'diet in Yushu,providing basic information for local otter management and ***,it represents a case showing that native predators prey on religious released animals,implying a probable direction forcontrolling invasive species through nativepredator conservation.

关键词： biological invasion Buddhism Eurasian otter prey composition religious wildlife release scat DNA.

SFC placement and dynamic resource allocation based on VNF performance-resource function and service requirement in cloud-edge environment

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Journal of Systems Engineering and Electronics 2024年第4期35卷 906-921页

作者： han Yingchao MENG Weixiao fan Wentao School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China China Mobile(Suzhou)Software Technology Company Limited Suzhou 215000China

With the continuous development of network func-tions virtualization(NFV)and software-defined networking(SDN)technologies and the explosive growth of network traffic,the requirement for computing resources in the network has risen *** to the high cost of edge computing resources,coordinating the cloud and edge computing resources to improve the utilization efficiency of edge computing resources is still a considerable *** this paper,we focus on optimiz-ing the placement of network services in cloud-edge environ-ments to maximize the *** is first proved that,in cloud-edge environments,placing one service function chain(SFC)integrally in the cloud or at the edge can improve the utilization efficiency of edge *** a virtual network function(VNF)performance-resource(P-R)function is proposed to repre-sent the relationship between the VNF instance computing per-formance and the allocated computing *** select the SFCs that are most suitable to deploy at the edge,a VNF place-ment and resource allocation model is built to configure each VNF with its particular P-R ***,a heuristic recur-sive algorithm is designed called the recursive algorithm for max edge throughput(RMET)to solve the *** simula-tions on two scenarios,it is verified that RMET can improve the utilization efficiency of edge computing resources.

关键词： cloud-edge environment virtual network function(VNF)performance-resource(P-R)function edge resource allo-cation

Mutations in the SARS-CoV-2 spike receptor binding domain and their delicate balance between ACE2 affinity and antibody evasion

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Protein & Cell 2024年第6期15卷 403-418页

作者： Song Xue Yuru han fan Wu Qiao Wang Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS) Shanghai Institute of Infectious Disease and BiosecurityShanghai Frontiers Science Center of Pathogenic Microorganisms and InfectionSchool of Basic Medical SciencesShanghai Medical CollegeFudan UniversityShanghai 200032China

Intensive selection pressure constrains the evolutionary trajectory of SARS-CoV-2 genomes and results in various novel variants with distinct mutation *** mutations,particularly those within the receptor binding domain(RBD)of SARS-CoV-2 spike(S)protein,lead to the functional alteration in both receptor engagement and monoclonal antibody(mAb)***,we review the data of the RBD point mutations possessed by major SARS-CoV-2 variants and discuss their individual effects on ACE2 affinity and immune *** single amino acid substitutions within RBD epitopes crucial for the antibody evasion capacity may conversely weaken ACE2 binding ***,this weakened effect could be largely compensated by specific epistatic mutations,such as N501Y,thus maintaining the overall ACE2 affinity for the spike protein of all major *** predominant direction of SARS-CoV-2 evolution lies neither in promoting ACE2 affinity nor evading mAb neutralization but in maintaining a delicate balance between these two ***,this review interprets how RBD mutations efficiently resist antibody neutralization and meanwhile how the affinity between ACE2 and spike protein is maintained,emphasizing the significance of comprehensive assessment of spike mutations.

关键词： ACE2 affinity maintained

Local search yields a PTAS for fixed-dimensional k-means problem with penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 351-362页

作者： fan Yuan Da-Chuan Xu dong-Lei Du dong-Mei Zhang Beijing Institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing 100124China Faculty of Management University of New BrunswickFrederictonNB E3B 9Y2Canada School of Computer Science and Technology Shandong Jianzhu UniversityJinan 250101ShandongChina

We study a problem called the k-means problem with penalties(k-MPWP),which is a natural generalization of the typical k-means *** this problem,we have a set D of client points in R^(d),a set F of possible centers in R^(d),and a penalty cost Pj>O for each point j∈*** are also given an integer k which is the size of the center point *** want to find a center point set S■F with size k,choose a penalized subset of clients P■D,and assign every client in D\P to its open *** goal is to minimize the sum of the squared distances between every point in D\P to its assigned centre point and the sum of the penalty costs for all clients in *** using the multi-swap local search technique and under the fixed-dimensional Euclidean space setting,we present a polynomial-time approximation scheme(PTAS)for the k-MPWP.

关键词： Approximation algorithm k-means Local search Penalty