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Evaluation of indoor air quality based on qualitative,quantitative and olfactory analysis

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Chinese Science Bulletin 2013年第9期58卷 986-991页

作者： yi Qin LIU JieMin WANG GuiHua ZHANG YanNi Department of Chemistry School of Chemical and Biological EngineeringUniversity of Science & Technology Beijing

In studying indoor atmospheric pollution,the concentration of air pollutants is considered to be the primary factor in judging indoor pollution level,while sensory effects accessed by olfactory analysis has not been paid enough *** this paper,twenty living rooms in Beijing including newly decorated,3 months and 6 months after decoration were sampled once a day for 10 d,and qualitative analysis,quantitative analysis and olfactory analysis of volatile organic compounds were carried *** results showed the concentrations of the 6 main compounds surpassed the limitation values released by World Health Organization;the pollutants with highest chemical concentrations were not the most odor active *** analysis which measured the odor characters such as odor detection threshold(ODT),odor active value(OAV) and odor quality was a helpful tool to identify possible chemicals which cause indoor smelling issues,and it was necessary to access indoor air quality in combination with their chemical concentrations to give a comprehensive judgment on indoor air quality.

关键词：室内空气质量空气质量评价嗅觉挥发性有机化合物空气污染物基础世界卫生组织化学物质

Cathodic biofouling control by microbial separators in air-breathing microbial fuel cells

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Environmental Science and Ecotechnology 2023年第3期15卷 35-43页

作者： Chao Li Kexin yi Shaogang Hu Wulin Yang College of Environmental Science and Engineering Peking UniversityNo.5 Yiheyuan RoadHaidian DistrictBeijing100871China

Microbial fuel cells(MFCs)incorporating air-breathing cathodes have emerged as a promising ecofriendly wastewater treatment technology capable of operating on an energy-free ***,the inevitable biofouling of these devices rapidly decreases cathodic catalytic activity and also reduces the stability of MFCs during long-term *** present work developed a novel microbial separator for use in air-breathing MFCs that protects cathodic catalytic *** these modified devices,microbes preferentially grow on the microbial separator rather than the cathodic surface such that biofouling is *** showed that this concept provided low charge transfer and mass diffusion resistance values during the cathodic oxygen reduction reaction of 4.6±1.3 and 17.3±6.8 U,respectively,after prolonged *** maximum power density was found to be stable at 1.06±0.07 W m2 throughout a long-term test and the chemical oxygen demand removal efficiency was increased to 92%compared with a value of 83%for MFCs exhibiting serious *** addition,a cathode combined with a microbial separator demonstrated less cross-cathode diffusion of oxygen to the *** effect indirectly induced the growth of electroactive bacteria and produced higher currents in air-breathing *** importantly,the present microbial separator concept enhances both the lifespan and economics of air-breathing MFCs by removing the need to replace or regenerate the cathode during longterm *** results indicate that the installation of a microbial separator is an effective means of stabilizing power generation and ensuring the cost-effective performance of air-breathing MFCs intended for future industrial applications.

关键词： Air-breathing MFC Microbial separator Niche-selective superiority Biofouling elimination Stability and sustainability

Comparison of two bedside evaluation methods of dysphagia in patients with acute stroke

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Stroke & Vascular Neurology 2018年第4期3卷 237-244页

作者： Ting Ye Shengyan Huang yi Dong Qiang Dong Neurology Unit Huashan HospitalFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology Fudan UniversityShanghaiShanghaiChina

Background Dysphagia is a common complication after *** swallowing test(WST)is a recognised but limited tool in providing details about dysphagia,including severity and how to adjust the diet based on the test *** We performed a prospective observational study of comparing WST and volume-viscosity swallow test(V-VST)in patients with acute stroke within 14 *** patients had WST and if failed would have a *** primary outcome was to compare the dysphagia levels assessed by these two test *** secondary outcome was to explore the predictive capability in patients who were at high risk of pneumonia by these two swallowing *** Consecutively 276 patients with stroke were enrolled in our study,and 197 had normal *** 79 patients who had both WST and V-VST,20 showed swallowing safety and effectiveness by *** chance of being on tube feeding was strongly related to the positive results of failed WST(p<0.001).Both tests showed good predictive ability in patients with stroke for pneumonia even some of them were placed on tube feeding(p=0.001 in WST and p<0.001 in V-VST).Conclusions V-VST performed better as a clinical screening test for dysphagia in patients with acute stroke at the *** registration number ChiCTR1800016442.

关键词： patients details viscosity

Late Devonian red tide and mass extinction

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Chinese Science Bulletin 2002年第13期47卷 1138-1144页

作者： GONG yiming LI Baohua SI Yuanlan WU yi Faculty of Earth Science China University of GeosciencesWuhan 430074China Laboratory of Marine Geology Tongji UniversityShanghai 200092China Department of Computer Science South-Central University for NationalitiesWuhan 430074China Guangxi Institute of Geology Nanning 530023China

Molecular stratigraphical, carbonate carbon isotopic, stratigraphical and paleontological data show that algal booming, eutrophication, anoxia, hypersalinity, positive δ13C excursion and biomass decreasing occurred in the offshore carbonate environments of the Frasnian-Famennian (F-F) transition, which hints that red tide might frequently take place in the F-F transition of Guangxi, South China. We suggest that the mass extinction of the reef ecosystems and the shallow-water marine organisms in the F-F transition of the lower-middle latitudes may be related to the frequent occurrence of red tide in that time.

关键词： red tide eutrophication mass extinction Devonian South China.

Additional symmetries of constrained CKP and BKP hierarchies

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Science China Mathematics 2011年第2期54卷 257-268页

作者： TIAN KeLei HE JingSong CHENG JiPeng CHENG yi Department of Mathematics University of Science and Technology of China Hefei 230026 China Department of Mathematics Ningbo University Ningbo 315211 China

The additional symmetries of the constrained CKP (cCKP) and BKP (cBKP) hierarchies are given by their actions on the Lax operators, and their actions on the eigenfunction and adjoint eigenfunction {Φ i , Ψ i } are presented explicitly. Furthermore, we show that acting on the space of the wave operator, *k forms new centerless W cC 1+∞ and W cB 1+∞ -subalgebra of centerless W 1+∞ respectively. In order to define above symmetry flows *k of the cCKP and cBKP hierarchies, two vital operators Y k are introduced to revise the additional symmetry flows of the CKP and BKP hierarchies.

关键词： constrained CKP hierarchy constrained BKP hierarchy additional symmetry

Global stability for a multi-group SVIR model with age of vaccination

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International Journal of Biomathematics 2018年第5期11卷 147-173页

作者： Chuncheng Wang Dejun Fan Ling Xia Xiaoyu yi Department of Mathematics Harbin Institute of Technology Harbin 150001 P. R. China Department of Mathematics Harbin Institute of Technology (Weihai) Weihai 264209 P. R. China

In this paper, a multi-group SVIR epidemic model with age of vaccination is considered. The model allows the vaccinated individuals to become susceptible after the vaccine loses its protective properties, and the vaccination classes satisfy first-order the partial differential equations structured by vaccination age. Combining the Lyapunov functional method with a graph-theoretic approach, we show that the global stability of endemic equilibrium for the strongly connected system is determined by the basic reproduction number. In addition, the dynamics for non-strongly connected model are also investi- gated, depending on the basic reproduction numbers corresponding to each strongly connected component. Numerical simulations are carried out to support the theoretical conclusions.

关键词： SVIR model age of vaccination global attractor global stability asymptotic smoothness.

The Aviation Technology Two-Sided Matching with the Expected Time Based on the Probabilistic Linguistic Preference Relations

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Journal of the Operations Research Society of China 2020年第1期8卷 45-77页

作者： Bo Li yi-Xin Zhang Ze-Shui Xu Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu 610207China Business School State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064China School of Computer Science University of ManchesterManchester M139PLUnited Kingdom

The two-sided matching has been widely applied to the decision-making problems in the field of *** the limited working experience,the two-sided agents usually cannot provide the preference order directly for the opposite agent,but rather to provide the preference relations in the form of linguistic *** preference relations based on probabilistic linguistic term sets(PLTSs)not only allowagents to provide the evaluation with multiple linguistic terms,but also present the different preference degrees for linguistic *** the diversities of the agents,they may provide their preference relations in the form of the probabilistic linguistic preference relation(PLPR)or the probabilistic linguistic multiplicative preference relation(PLMPR).For two-sided matching with the expected time,we first provide the concept of the time satisfaction degree(TSD).Then,we transform the preference relations in different forms into the unified preference relations(u-PRs).The consistency index to measure the consistency of u-PRs is ***,the acceptable consistent u-PRs are constructed,and an algorithm is proposed to modify the unacceptable consistent ***,we present the whole two-sided matching decisionmaking process with the acceptable consistent ***,a case about aviation technology suppliers and demanders matching is presented to exhibit the rationality and practicality of the proposed *** analyses and discussions are provided to further demonstrate the feasibility and effectiveness of the proposed method.

关键词： Two-sided matching Time satisfaction degree Probabilistic linguistic term sets Preference relation Aviation technology

Preference Value-Based Network Selection and Resource Allocation in Heterogeneous Wireless Networks

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Journal of Harbin Institute of Technology(New Series) 2015年第1期22卷 37-42页

作者： Tao Zhang yi Li Lanjie Zhai Jian Liu School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Network selection and resource allocation( NS-RA) are the processes of determining network and radio resource which provide the service to user. Optimizing these processes is an important step towards maximizing the utilization of current and future networks. In this paper,we proposed a preference value-based network selection and resource allocation,in which the NS scheme was performed by the joint radio resource management( JRRM) entity and the RA scheme was performed by the network. In the NS step,the JRRM entity selected the preferable network for users according to the preference value of each network,which took the load balance,the received signal strength( RSS) and the relative position between the user and the network into account. In the second step,the network allocated the optimal sub-carrier to user for the downlink transmission each round according to the preference value of each user and the maximum reachable data rate calculated by users' perceived channel information,maximizing the spectrum efficiency as well as guaranteeing the fairness. The simulation results showed that the proposed NS-RA scheme achieves better performance in terms of load distribution,spectrum efficiency and user fairness,compared to the conventional strategies.

关键词： heterogeneous wireless network preference value ne

miRNA-26b suppresses the TGF-β2-induced progression of HLE-B3 cells via the PI3K/Akt pathway

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1350-1358页

作者： En Shi Xiang-Nan Ye Liu-yi Xie Department of Ophthalmology Ningbo Eye HospitalNingbo 315040Zhejiang ProvinceChina Department of Ophthalmology Ningbo Medical Center Lihuili HospitalNingbo 315041Zhejiang ProvinceChina Department of Ophthalmology Beilun District Peopled HospitalNingbo 315826Zhejiang ProvinceChina

AIM:To study the effect of mi R-26 b on lens epithelial cells induced by transforming growth factor beta(TGF-β)2 and the underlying signaling ***:Human lens epithelial cell line B-3(HLE-B3)was incubated with TGF-β2(5 ng/m L)and then transfected with mi R-26 b *** expression of mi R-26 b was determined using quantitative reverse transcriptase polymerase chain reaction(q RT-PCR),while 5’-bromodeoxyuridine(Brd U)and wound-healing assays were used to measure the growth and migration of HLE-B3 cells,*** expression of epithelialmesenchymal transition(EMT)markers and the activity of the phosphatidylinositol 3-kinase(PI3 K)/Akt pathway were measured by Western blotting assay and immunofluorescence *** microscopy was also used to observe cellular ***:The expression levels of mi R-26 b were significantly reduced in human posterior capsular opacification-attached lens tissue and TGF-β2-stimulated HLE-B3 *** the presence of TGF-β2,the growth,migration,and EMT of HLE-B3 cells were distinctly enhanced;these effects were attenuated by the administration of mi R-26 b ***,the overexpression of mi R-26 b significantly reduced upregulation of the PI3 K/Akt pathway when stimulated by TGF-β2 in HLE-B3 ***,the addition of an activator(740 Y-P)led to the upregulation of the PI3 K/Akt pathway and abolished the protective effect of mi R-26 b on the HLE-B3 cells that was mediated by TGF-β***:The mi R-26 b suppresses TGF-β2-induced growth,migration,and EMT in HLE-B3 cells by regulating the PI3 K/Akt signaling pathway.

关键词： posterior capsule opacification miRNA-26b proliferation migration epithelial-mesenchymal transition