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Aspect-Level Sentiment Analysis Incorporating Semantic and Syntactic Information
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作者 Jiachen Yang Yegang Li +2 位作者 hao zhang Junpeng Hu Rujiang Bai 《Journal of Computer and Communications》 2024年第1期191-207,共17页
Aiming at the problem that existing models in aspect-level sentiment analysis cannot fully and effectively utilize sentence semantic and syntactic structure information, this paper proposes a graph neural network-base... Aiming at the problem that existing models in aspect-level sentiment analysis cannot fully and effectively utilize sentence semantic and syntactic structure information, this paper proposes a graph neural network-based aspect-level sentiment classification model. Self-attention, aspectual word multi-head attention and dependent syntactic relations are fused and the node representations are enhanced with graph convolutional networks to enable the model to fully learn the global semantic and syntactic structural information of sentences. Experimental results show that the model performs well on three public benchmark datasets Rest14, Lap14, and Twitter, improving the accuracy of sentiment classification. 展开更多
关键词 Aspect-Level Sentiment Analysis Attentional Mechanisms Dependent Syntactic Trees Graph Convolutional Neural Networks
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Blautia producta displays potential probiotic properties against dextran sulfate sodium-induced colitis in mice 被引量:3
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作者 Bingyong Mao Weiling Guo +4 位作者 Shumao Cui Qiuxiang zhang Jianxin Zhao Xin Tang hao zhang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期709-720,共12页
Blautia has attracted attention because of its potential efficacy in ameliorating host energy metabolism and inflammation.This study aims to investigate the influences of Blautia producta D4 on colitis induced by dext... Blautia has attracted attention because of its potential efficacy in ameliorating host energy metabolism and inflammation.This study aims to investigate the influences of Blautia producta D4 on colitis induced by dextran sulfate sodium(DSS)and to reveal the underlying mechanisms.Results showed that B.producta D4 intervention significantly relieved body weight loss,and suppressed the elevation of pro-inflammatory cytokines(including interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),and interleukin-1β(IL-1β))and excessive oxidative stress(myeloperoxidease(MPO)activity,superoxide dismutase(SOD)activity,glutathione peroxidase(GSH-Px)activity,and malondialdehyde(MDA)level)in colitis mice.Moreover,the concentrations of tight junction proteins(occludin,claudin-1,and ZO-1)related to the intestinal barrier were obviously elevated,and colitis-related TLR4/NF-κB pathway activation was remarkably inhibited after B.producta D4 intervention.The intestinal microbial disorder was evidently ameliorated by increasing the relative abundance of Clostridium sensu stricto 1,Bifidobacterium,GCA-900066225,Enterorhabdus,and reducing the relative abundance of Lachnospiraceae NK4A136 group.In conclusion,oral administration of B.producta D4 could ameliorate DSS-induced colitis by suppressing inflammatory responses,maintaining the intestinal barrier,inhibiting TLR4/NF-κB pathway,and regulating intestinal microbiota balance.These results are conducive to accelerate the development of B.producta D4 as a functional probiotic for colitis. 展开更多
关键词 Blautia producta D4 COLITIS Intestinal mechanical barrier TLR4/NF-κB pathway Intestinal microbiot
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增大冷速和退火对Al_(50)Ni_(50)合金耐蚀性能的改善
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作者 刘瀚泽 闫芝成 +7 位作者 陈其 张昊 冯玉 齐志港 王兆萱 潘少鹏 贾义勇 王伟民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第3期769-785,共17页
通过周向速度(S_(c))分别为21和42 m/s的熔带甩带法制备单相Al_(50)Ni_(50)条带,然后采用多种实验方法研究在不同温度下退火Al_(50)Ni_(50)条带的显微组织和腐蚀行为。随着S_(c)从21 m/s提高到42 m/s,相应的铸态和退火条带的(100)晶体... 通过周向速度(S_(c))分别为21和42 m/s的熔带甩带法制备单相Al_(50)Ni_(50)条带,然后采用多种实验方法研究在不同温度下退火Al_(50)Ni_(50)条带的显微组织和腐蚀行为。随着S_(c)从21 m/s提高到42 m/s,相应的铸态和退火条带的(100)晶体取向因子F(100)增大,再结晶的障碍减少以及钝化膜的总电阻增大。S_(c)=42m/s的铸态条带比21 m/s的铸态和退火的条带具有更稳定、更致密的Al_(2)O_(3)钝化膜,并可以通过在700℃退火进一步提升。因此,提高冷却速率和选择适当温度进一步退火可以提高AlNi条带的耐腐蚀性能。 展开更多
关键词 AlNi合金 快速凝固 取向因子 再结晶 腐蚀性为
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Insight into structure evolution of carbon nitrides and its energy conversion as luminescence
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作者 hao zhang Jingwei zhang +4 位作者 Wenjie Chen Minjia Tao Xianguang Meng Yuanjian zhang Guifu Zuo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第2期37-60,共24页
A series of carbon nitride(CN)materials represented by graphitic carbon nitride(g-C3N4)have been widely used in bioimaging,biosensing,and other fields in recent years due to their nontoxicity,low cost,and high lumines... A series of carbon nitride(CN)materials represented by graphitic carbon nitride(g-C3N4)have been widely used in bioimaging,biosensing,and other fields in recent years due to their nontoxicity,low cost,and high luminescent quantum efficiency.What is more attractive is that the luminescent properties such as wavelength and intensity can be regulated by controlling the structure at the molecular level.Hence,it is time to summarize the related research on CN structural evolution and make a prospect on future developments.In this review,we first summarize the research history and multiple structural evolution of CN.Then,the progress of improving the luminescence performance of CN through structural evolution was discussed.Significantly,the relationship between CN structure evolution and energy conversion in the forms of photoluminescence,chemiluminescence,and electrochemiluminescence was reviewed.Finally,key challenges and opportunities such as nanoscale dispersion strategy,luminous efficiency improving methods,standardization evaluation,and macroscopic preparation of CN are highlighted. 展开更多
关键词 carbon nitride CHEMILUMINESCENCE ELECTROCHEMILUMINESCENCE energy conversion PHOTOLUMINESCENCE structural evolution
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Mechanisms underlying the role of endoplasmic reticulum stress in the placental injury and fetal growth restriction in an ovine gestation model
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作者 hao zhang Xia Zha +5 位作者 Yi Zheng Xiaoyun Liu Mabrouk Elsabagh Hongrong Wang Honghua Jiang Mengzhi Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期201-217,共17页
Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine mode... Background Exposure to bisphenol A(BPA),an environmental pollutant known for its endocrine-disrupting properties,during gestation has been reported to increase the risk of fetal growth restriction(FGR)in an ovine model of pregnancy.We hypothesized that the FGR results from the BPA-induced insufficiency and barrier dysfunction of the placenta,oxidative stress,inflammatory responses,autophagy and endoplasmic reticulum stress(ERS).However,precise mechanisms underlying the BPA-induced placental dysfunction,and subsequently,FGR,as well as the potential involvement of placental ERS in these complications,remain to be investigated.Methods In vivo experiment,16 twin-pregnant(from d 40 to 130 of gestation)Hu ewes were randomly distributed into two groups(8 ewes each).One group served as a control and received corn oil once a day,whereas the other group received BPA(5 mg/kg/d as a subcutaneous injection).In vitro study,ovine trophoblast cells(OTCs)were exposed to 4 treatments,6 replicates each.The OTCs were treated with 400μmol/L BPA,400μmol/L BPA+0.5μg/m L tunicamycin(Tm;ERS activator),400μmol/L BPA+1μmol/L 4-phenyl butyric acid(4-PBA;ERS antagonist)and DMEM/F12 complete medium(control),for 24 h.Results In vivo experiments,pregnant Hu ewes receiving the BPA from 40 to 130 days of pregnancy experienced a decrease in placental efficiency,progesterone(P4)level and fetal weight,and an increase in placental estrogen(E2)level,together with barrier dysfunctions,OS,inflammatory responses,autophagy and ERS in type A cotyledons.In vitro experiment,the OTCs exposed to BPA for 24 h showed an increase in the E2 level and related protein and gene expressions of autophagy,ERS,pro-apoptosis and inflammatory response,and a decrease in the P4 level and the related protein and gene expressions of antioxidant,anti-apoptosis and barrier function.Moreover,treating the OTCs with Tm aggravated BPA-induced dysfunction of barrier and endocrine(the increased E2 level and decreased P4 level),OS,inflammatory responses,autophagy,and ERS.However,treating the OTCs with 4-PBA reversed the counteracted effects of Tm mentioned above.Conclusions In general,the results reveal that BPA exposure can cause ERS in the ovine placenta and OTCs,and ERS induction might aggravate BPA-induced dysfunction of the placental barrier and endocrine,OS,inflammatory responses,and autophagy.These data offer novel mechanistic insights into whether ERS is involved in BPA-mediated placental dysfunction and fetal development. 展开更多
关键词 AUTOPHAGY Bisphenol A Endoplasmic reticulum stress Fetal growth restriction Inflammatory responses SHEEP
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Ultrathin Zincophilic Interphase Regulated Electric Double Layer Enabling Highly Stable Aqueous Zinc‑Ion Batteries
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作者 Yimei Chen Zhiping Deng +5 位作者 Yongxiang Sun Yue Li hao zhang Ge Li Hongbo Zeng Xiaolei Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期285-299,共15页
The practical application of aqueous zinc-ion batteries for large-grid scale systems is still hindered by uncontrolled zinc dendrite and side reactions.Regulating the elec-trical double layer via the electrode/electro... The practical application of aqueous zinc-ion batteries for large-grid scale systems is still hindered by uncontrolled zinc dendrite and side reactions.Regulating the elec-trical double layer via the electrode/electrolyte interface layer is an effective strategy to improve the stability of Zn anodes.Herein,we report an ultrathin zincophilic ZnS layer as a model regu-lator.At a given cycling current,the cell with Zn@ZnS electrode displays a lower potential drop over the Helmholtz layer(stern layer)and a suppressed diffuse layer,indicating the regulated charge distribution and decreased electric double layer repulsion force.Boosted zinc adsorption sites are also expected as proved by the enhanced electric double-layer capacitance.Consequently,the symmetric cell with the ZnS protection layer can stably cycle for around 3,000 h at 1 mA cm^(-2) with a lower overpotential of 25 mV.When coupled with an I2/AC cathode,the cell demonstrates a high rate performance of 160 mAh g^(-1) at 0.1 A g^(-1) and long cycling stability of over 10,000 cycles at 10 A g^(-1).The Zn||MnO_(2) also sustains both high capacity and long cycling stability of 130 mAh g^(-1) after 1,200 cycles at 0.5 A g^(-1). 展开更多
关键词 Zinc anode Electric double-layer regulation Multifunction SEI layer Inhibited side reactions and dendrite Rapid kinetics
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Evaluating the performance of genomic selection on purebred population by incorporating crossbred data in pigs
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作者 Jun Zhou Qing Lin +10 位作者 Xueyan Feng Duanyang Ren Jinyan Teng Xibo Wu Dan Wu Xiaoke zhang Xiaolong Yuan Zanmou Chen Jiaqi Li Zhe zhang hao zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期639-648,共10页
Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it... Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it was limited by the purebred population.Compared to directly combining two uncorrelated purebred populations to extend the reference population size,it might be more meaningful to incorporate the correlated crossbreds into reference population for genomic prediction.In this study,we simulated purebred offspring(PAS and PBS)and crossbred offspring(CAB)base on real genotype data of two base purebred populations(PA and PB),to evaluate the performance of genomic selection on purebred while incorporating crossbred information.The results showed that selecting key crossbred individuals via maximizing the expected genetic relationship(REL)was better than the other methods(individuals closet or farthest to the purebred population,CP/FP)in term of the prediction accuracy.Furthermore,the prediction accuracy of reference populations combining PA and CAB was significantly better only based on PA,which was similar to combine PA and PAS.Moreover,the rank correlation between the multiple of the increased relationship(MIR)and reliability improvement was 0.60-0.70.But for individuals with low correlation(Cor(Pi,PA or B),the reliability improvement was significantly lower than other individuals.Our findings suggested that incorporating crossbred into purebred population could improve the performance of genetic prediction compared with using the purebred population only.The genetic relationship between purebred and crossbred population is a key factor determining the increased reliability while incorporating crossbred population in the genomic prediction on pure bred individuals. 展开更多
关键词 PIGS crossbred population genomic selection reference population construction relationship
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Hard-carbon hybrid Li-ion/metal anode enabled by preferred mesoporous uniform lithium growth mechanism
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作者 Fang Yan Yan Liu +11 位作者 Yuan Li Yan Wang Zicen Deng Meng Li Zhenwei Zhu Aohan Zhou Ting Li Jingyi Qiu Gaoping Cao Shaobo Huang Biyan Wang hao zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期252-259,I0006,共9页
To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising strategy.In particular,because of the anisotropy of graphite,hybrid anode formed by graphite/Li me... To achieve high energy density in lithium batteries,the construction of lithium-ion/metal hybrid anodes is a promising strategy.In particular,because of the anisotropy of graphite,hybrid anode formed by graphite/Li metal has low transport kinetics and is easy to causes the growth of lithium dendrites and accumulation of dead Li,which seriously affects the cycle life of batteries and even causes safety problems.Here,by comparing graphite with two types of hard carbon,it was found that hybrid anode formed by hard carbon and lithium metal,possessing more disordered mesoporous structure and lithophilic groups,presents better performance.Results indicate that the mesoporous structure provides abundant active site and storage space for dead lithium.With the synergistic effect of this structure and lithophilic functional groups(–COOH),the reversibility of hard carbon/lithium metal hybrid anode is maintained,promoting uniform deposition of lithium metal and alleviating formation of lithium dendrites.The hybrid anode maintains a 99.5%Coulombic efficiency(CE)after 260 cycles at a specific capacity of 500 m Ah/g.This work provides new insights into the hybrid anodes formed by carbon-based materials and lithium metal with high specific energy and fast charging ability. 展开更多
关键词 Hard carbon/Li metal hybrid anode Mesoporous structure Surface oxygen functional group Fast charging Lithium batteries
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Atomically dispersed Fe sites on hierarchically porous carbon nanoplates for oxygen reduction reaction
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作者 Ruixue Zheng Qinglei Meng +9 位作者 hao zhang Teng Li Di Yang Li zhang Xiaolong Jia Changpeng Liu Jianbing Zhu Xiaozheng Duan Meiling Xiao Wei Xing 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期7-15,I0002,共10页
Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air bat... Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air batteries.Although Fe-N-C single atom catalysts(SACs) have been hailed as the most promising candidate due to the optimal binding strength of ORR intermediates on the Fe-N_(4) sites,they suffer from serious mass transport limitations as microporous templates/substrates,i.e.,zeolitic imidazolate frameworks(ZIFs),are usually employed to host the active sites.Motivated by this challenge,we herein develop a hydrogen-bonded organic framework(HOF)-assisted pyrolysis strategy to construct hierarchical micro/mesoporous carbon nanoplates for the deposition of atomically dispersed Fe-N_(4) sites.Such a design is accomplished by employing HOF nanoplates assembled from 2-aminoterephthalic acid(NH_(2)-BDC) and p-phenylenediamine(PDA) as both soft templates and C,N precursors.Benefitting from the structural merits inherited from HOF templates,the optimized catalyst(denoted as Fe-N-C SAC-950) displays outstanding ORR activity with a high half-wave potential of 0.895 V(vs.reversible hydrogen electrode(RHE)) and a small overpotential of 356 mV at 10 mA cm^(-2) for the oxygen evolution reaction(OER).More excitingly,its application potential is further verified by delivering superb rechargeability and cycling stability with a nearly unfading charge-discharge gap of 0.72 V after 160 h.Molecular dynamics(MD) simulations reveal that micro/mesoporous structure is conducive to the rapid mass transfer of O_(2),thus enhancing the ORR performance.In situ Raman results further indicate that the conversion of O_(2) to~*O_(2)-the rate-determining step(RDS) for Fe-N-C SAC-950.This work will provide a versatile strategy to construct single atom catalysts with desirable catalytic properties. 展开更多
关键词 Fe single atom catalysts Oxygen reduction reaction Mesoporous structure Active sites Zinc-air battery
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Environmental enrichment in combination with Bifidobacterium breve HNXY26M4 intervention amplifies neuroprotective benefits in a mouse model of Alzheimer's disease by modulating glutamine metabolism of the gut microbiome
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作者 Guangsu Zhu Min Guo +3 位作者 Jianxin Zhao hao zhang Gang Wang Wei Chen 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期982-992,共11页
The gut microbiota-brain axis has emerged as a novel target for Alzheimer's disease(AD),a neurodegenerative disease characterised by behavioural and cognitive impairment.However,most previous microbiome-based inte... The gut microbiota-brain axis has emerged as a novel target for Alzheimer's disease(AD),a neurodegenerative disease characterised by behavioural and cognitive impairment.However,most previous microbiome-based intervention studies have focused on single factors and yielded only modest cognitive improvements.Here,we proposed a multidomain intervention strategy that combined Bifidobacterium breve treatment with environmental enrichment(EE)training.In this study,we found that compared with EE or B.breve treatment alone,B.breve intervention combined with EE amplified its neuroprotective effects on AD mice,as reflected by improved cognition,inhibited neuroinflammation and enhanced synaptic function.Moreover,using microbiome and metabolome profiling,we found that the combination of B.breve and EE treatment restored AD-related gut microbiota dysbiosis and reversed microbial metabolite changes.Finally,by integrating behavioural and neurological data with metabolomic profiles,we revealed that the underlying mechanism may involve the modulation of microbiota-derived glutamine metabolism via gut-brain interactions.Collectively,combined B.breve intervention with EE treatment can alleviate AD-related cognitive impairment and improve brain function by regulating glutamine metabolism of the gut microbiome.Our findings provide a promising multidomain intervention strategy,with a combination of dietary microbiome-based and lifestyle-targeted interventions,to promote brain function and delay the progression of AD. 展开更多
关键词 Alzheimer’s disease Bifidobacterium breve Environmental enrichment Glutamine metabolism Microbiota-gut-brain axis
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Deep Learning and Tensor-Based Multiple Clustering Approaches for Cyber-Physical-Social Applications
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作者 Hongjun zhang hao zhang +3 位作者 Yu Lei hao Ye Peng Li Desheng Shi 《Computers, Materials & Continua》 SCIE EI 2024年第3期4109-4128,共20页
The study delves into the expanding role of network platforms in our daily lives, encompassing various mediums like blogs, forums, online chats, and prominent social media platforms such as Facebook, Twitter, and Inst... The study delves into the expanding role of network platforms in our daily lives, encompassing various mediums like blogs, forums, online chats, and prominent social media platforms such as Facebook, Twitter, and Instagram. While these platforms offer avenues for self-expression and community support, they concurrently harbor negative impacts, fostering antisocial behaviors like phishing, impersonation, hate speech, cyberbullying, cyberstalking, cyberterrorism, fake news propagation, spamming, and fraud. Notably, individuals also leverage these platforms to connect with authorities and seek aid during disasters. The overarching objective of this research is to address the dual nature of network platforms by proposing innovative methodologies aimed at enhancing their positive aspects and mitigating their negative repercussions. To achieve this, the study introduces a weight learning method grounded in multi-linear attribute ranking. This approach serves to evaluate the significance of attribute combinations across all feature spaces. Additionally, a novel clustering method based on tensors is proposed to elevate the quality of clustering while effectively distinguishing selected features. The methodology incorporates a weighted average similarity matrix and optionally integrates weighted Euclidean distance, contributing to a more nuanced understanding of attribute importance. The analysis of the proposed methods yields significant findings. The weight learning method proves instrumental in discerning the importance of attribute combinations, shedding light on key aspects within feature spaces. Simultaneously, the clustering method based on tensors exhibits improved efficacy in enhancing clustering quality and feature distinction. This not only advances our understanding of attribute importance but also paves the way for more nuanced data analysis methodologies. In conclusion, this research underscores the pivotal role of network platforms in contemporary society, emphasizing their potential for both positive contributions and adverse consequences. The proposed methodologies offer novel approaches to address these dualities, providing a foundation for future research and practical applications. Ultimately, this study contributes to the ongoing discourse on optimizing the utility of network platforms while minimizing their negative impacts. 展开更多
关键词 Network platform tensor-based clustering weight learning multi-linear euclidean
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Differences in the effects and action modes of gut commensals against dextran sulfate sodium-induced intestinal inflammation
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作者 Dingwu Qu Zhennan Gu +5 位作者 Saisai Feng Leilei Yu Fengwei Tian hao zhang Wei Chen Qixiao Zhai 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1201-1211,共11页
Inflammatory bowel disease(IBD)is a complex relapsing inflammatory disease in the gut and is driven by complicated host-gut microbiome interactions.Gut commensals have shown different functions in IBD prevention and t... Inflammatory bowel disease(IBD)is a complex relapsing inflammatory disease in the gut and is driven by complicated host-gut microbiome interactions.Gut commensals have shown different functions in IBD prevention and treatment.To gain a mechanistic understanding of how different commensals affect intestinal inflammation,we compared the protective effects of 6 probiotics(belonging to the genera Akkermansia,Bifidobacterium,Clostridium,and Enterococcus)on dextran sulfate sodium(DSS)-induced colitis in mice with or without gut microbiota.Anti-inflammatory properties(ratio of interleukin(IL)-10 and IL-12)of these strains were also evaluated in an in vitro mesenteric lymph nodes(MLN)co-culture system.Results showed that 4 probiotics(belonging to the species Bifidobacterium breve,Bifidobacterium bifidum,and Enterococcus faecalis)can alleviate colitis in normal mice.The probiotic strains differed in regulating the intestinal microbiota,cytokines(IL-10,IL-1βand interferon(IFN)-γ),and tight junction function(Zonulin-1 and Occludin).By constrast,Akkermansia muciniphila AH39 and Clostridium butyricum FHuNHHMY49T1 were not protective.Interestingly,B.breve JSNJJNM2 with high anti-inflammatory potential in the MLN model could relieve colitis symptoms in antibiotic cocktail(Abx)-treated mice.Meanwhile,E.faecalis FJSWX25M1induced low levels of cytokines in vitro and showed no beneficial effects.Therefore,we provided insight into the clinical application of probiotics in IBD treatment. 展开更多
关键词 Gut commensals Dextran sulfate sodium(DSS)colitis Intestinal barrier IMMUNOREGULATION
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Policy Gradient Adaptive Dynamic Programming for Model-Free Multi-Objective Optimal Control
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作者 hao zhang Yan Li +2 位作者 Zhuping Wang Yi Ding Huaicheng Yan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1060-1062,共3页
Dear Editor,In this letter,the multi-objective optimal control problem of nonlinear discrete-time systems is investigated.A data-driven policy gradient algorithm is proposed in which the action-state value function is... Dear Editor,In this letter,the multi-objective optimal control problem of nonlinear discrete-time systems is investigated.A data-driven policy gradient algorithm is proposed in which the action-state value function is used to evaluate the policy.In the policy improvement process,the policy gradient based method is employed. 展开更多
关键词 POLICY GRADIENT OPTIMAL
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More Than Lightening:A Self-Supervised Low-Light Image Enhancement Method Capable for Multiple Degradations
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作者 Han Xu Jiayi Ma +3 位作者 Yixuan Yuan hao zhang Xin Tian Xiaojie Guo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期622-637,共16页
Low-light images suffer from low quality due to poor lighting conditions,noise pollution,and improper settings of cameras.To enhance low-light images,most existing methods rely on normal-light images for guidance but ... Low-light images suffer from low quality due to poor lighting conditions,noise pollution,and improper settings of cameras.To enhance low-light images,most existing methods rely on normal-light images for guidance but the collection of suitable normal-light images is difficult.In contrast,a self-supervised method breaks free from the reliance on normal-light data,resulting in more convenience and better generalization.Existing self-supervised methods primarily focus on illumination adjustment and design pixel-based adjustment methods,resulting in remnants of other degradations,uneven brightness and artifacts.In response,this paper proposes a self-supervised enhancement method,termed as SLIE.It can handle multiple degradations including illumination attenuation,noise pollution,and color shift,all in a self-supervised manner.Illumination attenuation is estimated based on physical principles and local neighborhood information.The removal and correction of noise and color shift removal are solely realized with noisy images and images with color shifts.Finally,the comprehensive and fully self-supervised approach can achieve better adaptability and generalization.It is applicable to various low light conditions,and can reproduce the original color of scenes in natural light.Extensive experiments conducted on four public datasets demonstrate the superiority of SLIE to thirteen state-of-the-art methods.Our code is available at https://github.com/hanna-xu/SLIE. 展开更多
关键词 Color correction low-light image enhancement self-supervised learning.
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The Influence of Acid on the RockMechanical Characteristics of Deep Shale in theWujiaping Formation
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作者 hao zhang Yan zhang +2 位作者 Wei Liu Ximin zhang Xiang Liu 《Energy Engineering》 EI 2024年第1期27-42,共16页
The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to ... The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation,based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation.The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion.And a 15%concentration of hydrochloric acid can effectively dissolve shale.Furthermore,the degree of acid-etching reaction is highly variable because of the different carbonate content,which reveals the strong inhomogeneity of the shale system in the Wujiaping Group reservoir section.After the acid interacted with the shale rock samples,the triaxial compressive strength,elastic modulus,and Poisson’s ratio of shale decreased.Moreover,the evaluation of the effect after acid fracturing simulated by fracturing software revealed that the smaller the value of elastic modulus in shale-based reservoirs,the more favorable the fracture volume modification.This discovery not only provides a theoretical basis for the expansion and extension patterns of acid-fracturing in carbonaceous shale formations but also offers research methods and theoretical insights for the fundamental exploration of other deep-seated oil and gas resources. 展开更多
关键词 SHALE acid fracturing macro characteristics microscopic characteristics mechanical properties
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A Knowledge-Integrate Cross-Domain Data Generation Method for Aspect and Opinion Co-Extraction
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作者 hao zhang Yegang Li +1 位作者 Jiachen Yang Rujiang Bai 《Journal of Computer and Communications》 2023年第12期31-48,共18页
To address the difficulty of training high-quality models in some specific domains due to the lack of fine-grained annotation resources, we propose in this paper a knowledge-integrated cross-domain data generation met... To address the difficulty of training high-quality models in some specific domains due to the lack of fine-grained annotation resources, we propose in this paper a knowledge-integrated cross-domain data generation method for unsupervised domain adaptation tasks. Specifically, we extract domain features, lexical and syntactic knowledge from source-domain and target-domain data, and use a masking model with an extended masking strategy and a re-masking strategy to obtain domain-specific data that remove domain-specific features. Finally, we improve the sequence generation model BART and use it to generate high-quality target domain data for the task of aspect and opinion co-extraction from the target domain. Experiments were performed on three conventional English datasets from different domains, and our method generates more accurate and diverse target domain data with the best results compared to previous methods. 展开更多
关键词 Knowledge-Integrate Domain Adaptation Text Generation Aspect and Opinion Co-Extraction
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钢渣基功能填料的高附加值非建材领域应用研究进展
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作者 张浩 司乐琦 +4 位作者 王林 程峥明 刘自民 黄华 容北国 《材料工程》 EI CAS CSCD 北大核心 2023年第9期52-59,共8页
人类在面临一次资源日益枯竭的同时,又必须面对因一次资源消耗带来的固废难处理问题。因此,在充分考察钢渣性质基础上,利用钢渣特性,研发可以用于橡胶、涂料、塑料领域的钢渣基功能填料,有望实现钢渣跨产业生态链及高附加值利用,具有巨... 人类在面临一次资源日益枯竭的同时,又必须面对因一次资源消耗带来的固废难处理问题。因此,在充分考察钢渣性质基础上,利用钢渣特性,研发可以用于橡胶、涂料、塑料领域的钢渣基功能填料,有望实现钢渣跨产业生态链及高附加值利用,具有巨大经济价值与重要现实意义。钢渣基功能填料具有吸附性强、粒径小、与有机体系相容性好等特征,在橡胶输送带、钢结构防锈涂料、建筑外墙涂料、人造复合板材等领域具有广泛应用的潜力。本文首先对钢渣的特性、钢渣基功能填料的制备原理做了简要介绍;并就钢渣基功能填料作为橡胶填料、涂料颜填料与塑料填料的应用情况进行了具体分析。然后详细指出钢渣基功能填料用于橡胶复合材料、建筑外墙底漆、建筑外墙涂料、PVC微发泡板材的特点,并就目前钢渣基功能填料的局限性进行详细评述。在此基础上,指出优化钢渣基功能填料性能与开发多固废基协同复合功能填料,是钢渣基功能填料未来主要发展方向。 展开更多
关键词 钢渣基功能填料 橡胶填料 涂料颜填料 塑料涂料 固废利用
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北京地区不同城市热岛指标和城市效应研究方法的对比分析 被引量:1
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作者 张昊 张宁 潘志华 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第2期189-200,共12页
城市热岛效应是城市气候的突出现象之一,由于观测手段差异和数据代表性的不同,对城市热岛存在多种定义,其中冠层城市热岛和地表城市热岛的应用最广泛,但是目前两者之间的比较工作开展相对较少.“城市效应”是指由于城市的出现对一个地... 城市热岛效应是城市气候的突出现象之一,由于观测手段差异和数据代表性的不同,对城市热岛存在多种定义,其中冠层城市热岛和地表城市热岛的应用最广泛,但是目前两者之间的比较工作开展相对较少.“城市效应”是指由于城市的出现对一个地区气候的影响,城市热岛本质上属于城市效应的表征之一.分离“城市效应”常用的方法有“城乡差异”和“城市化前后对比”两种,二者分别从观测资料的空间和时间差异着手计算,目前对两种方法结论的一致性分析尤为欠缺.以北京地区为研究对象,利用地面气象站和卫星遥感观测数据,对比分析了该地区气温和地表温度、冠层热岛和地表热岛的数值与变化情况,并进一步分析了分离“城市增温效应”两种方法的可比性,结果表明:(1)2009-2017年北京地区五种热岛指标均值比较为:由卫星遥感反演得到的日间地表热岛最大,其次为地面观测得到的最低气温冠层热岛和卫星遥感反演得到的夜间地表热岛,二者数值相近,地面观测得到的平均气温冠层热岛再次,而地面观测得到的最高气温冠层热岛远小于其他四类;(2)以通州站为例,1980-2017年用以分离“城市增温效应”的城市化前后差异和城乡对比两种方法的结果分别为0.65℃/(10a)和0.61℃/(10a),结论基本一致,虽然由于乡村站平均气温受到城市化影响,城乡对比法存在低估现象,但误差在可接受范围内,两种方法仍具有相互替代性. 展开更多
关键词 城市热岛效应 冠层城市热岛 地表城市热岛 城市效应
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骨科植入物无机抗菌涂层的研究现状
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作者 张卓 马迅 +3 位作者 刘平 王静静 章浩 李伟 《材料工程》 EI CAS CSCD 北大核心 2023年第9期13-27,共15页
植入物感染是骨科最常见和最严重的并发症之一,也是导致植入手术失败的重要原因。当细菌在植入物表面形成生物膜后会极难消除,并吸附更多的细菌和真菌。大量研究表明,通过采用表面改性技术可有效减少致病菌的黏附和聚积,进而预防植入物... 植入物感染是骨科最常见和最严重的并发症之一,也是导致植入手术失败的重要原因。当细菌在植入物表面形成生物膜后会极难消除,并吸附更多的细菌和真菌。大量研究表明,通过采用表面改性技术可有效减少致病菌的黏附和聚积,进而预防植入物周围感染。本文首先分析了细菌生物膜在骨科植入物表面的形成过程以及金属抗菌剂的抗菌机制。然后综述了目前国内外使用最广泛的一些金属基无机抗菌涂层及其相关的制备工艺,讨论了这些涂层在应用中存在的问题和改善方法,并展望了未来无机抗菌涂层的发展方向,包括协同抗菌型涂层和促成骨型抗菌涂层等。 展开更多
关键词 骨科植入体 无机抗菌涂层 制备工艺 组织结构 生物相容性 银纳米颗粒
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2195铝锂合金的温热低周疲劳行为和疲劳寿命预测
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作者 孟子杰 张存生 +4 位作者 吴承格 张豪 陈良 赵国群 闫海 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第9期2574-2587,共14页
为研究2195铝锂合金在温热条件下(100和200℃)的低周疲劳行为,首先进行应变控制的低周疲劳试验。结果表明,合金的起始和中值寿命滞回环均呈现中心对称特征。在100℃、应变幅值为0.6%条件下的循环应力响应曲线表现出完全循环硬化特征,而... 为研究2195铝锂合金在温热条件下(100和200℃)的低周疲劳行为,首先进行应变控制的低周疲劳试验。结果表明,合金的起始和中值寿命滞回环均呈现中心对称特征。在100℃、应变幅值为0.6%条件下的循环应力响应曲线表现出完全循环硬化特征,而其他条件下的循环应力响应曲线均呈先循环硬化、然后循环软化的循环特征。随后,采用多种低周疲劳寿命预测模型对2195铝锂合金疲劳寿命进行评价。结果表明,基于总应变能密度的寿命预测模型具有最佳的预测精度。最后,为揭示2195铝锂合金的疲劳断裂机理,对不同试验条件下合金的疲劳断口进行观察。结果表明,在100℃、应变幅值为0.6%的条件下,合金断面上的疲劳条纹十分明显,但随着试验温度和应变幅值的升高,合金断面上的疲劳条纹逐渐弱化。在温度为200℃、应变幅值为1.0%条件下的疲劳断口呈明显沿晶断裂特征。 展开更多
关键词 2195铝锂合金 低周疲劳行为 疲劳寿命预测 疲劳断裂行为
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