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Influence of indoor airflow on airborne disease transmission in a classroom

Building Simulation 2024年第3期17卷 355-370页

作者： mojtaba Zabihi ri Li Joshua Brinkerhoff School of Engineering Faculty of Applied ScienceUniversity of British ColumbiaKelownaCanada

It has been widely accepted that the most effective way to mitigate airborne disease transmission in an indoor space is to increase the ventilation airflow,measured in air change per hour(AcH).However,increasing AcH did not effectively prevent the spread of cOVID-19.To better understand the role of AcH and airflow large-scale patterns,a comprehensive fully transient computational fluid dynamics(cFD)simulation of two-phase flows based on a discrete phase model(DPm)was performed in a university classroom setting with people present.The investigations encompass various particle sizes,ventilation layouts,and flow rates.The findings demonstrated that the particle size threshold at which particles are deemed airborne is highly influenced by the background flow strength and large-scale flow pattern,ranging from 5µm to 10µm in the cases investigated.The effects of occupants are significant and must be precisely accounted for in respiratory particle transport studies.An enhanced ventilation design(UFAD-cDR)for university classrooms is introduced that places a premium on mitigating airborne disease spread.compared to the baseline design at the same AcH,this design successfully reduced the maximum number density of respiratory particles by up to 85%.A novel airflow-related parameter,Horizontality,is introduced to quantify and connect the large-scale airflow pattern with indoor aerosol transport.This underscores that AcH alone cannot ensure or regulate air quality.In addition to the necessary AcH for air exchange,minimizing horizontal bulk motion is essential for reducing aerosol transmissibility within the room.

关键词： aerosol transmission airflow pattern horizontality cOVID-19 simulation classroom ventilation

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microstructure change in Fe-based metallic glass and nanocrystalline alloy induced by liquid nitrogen treatment

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Journal of materials Science & Technology 2021年第10期69卷 1-6页

作者： m.c.ri D.W.Ding Y.H.Sun W.H.Wang Institute of Physics Chinese Academy of SciencesBeijing100190China Songshan Lake materials Laboratory Dongguan523808China

The effects of acyclic liquid nitrogen(LN)treatment in a temperature range of-196℃to 50℃on the thermal and magnetic stability of Fe78Si9B13 and Fe73.5Si13.5B9Nb3cu1 glassy ribbons have been studied.The intrinsic heterogeneities of the metallic glasses can be activated through cryogenic thermal cycling,making irreversible structural changes after the treatment and inducing rejuvenation to the materials.The microstructural changes of both Fe-based metallic glass(mG)and nanocrystalline alloy induced by LN treatment were investigated.The experimental results show that the LN treatment could effectively rejuvenate the Fe-Si-B mGs and change their thermomechanical and magnetic properties.Based on the partially-crystallinity and well-known magnetic constants,the increase of the energy at the order of 10m J/g and magnetic domain wall movement and rotation at the order of 5-6μm and 0.5°-0.8°are found for FINEmET-type amorphous alloy after LN treatment.It is also found that LN treatment can contribute a little stored energy to the magnetic domain wall movement and magnetic domain rotation.

关键词： metallic glasses cryogenic thermal treatment Soft magnetic materials Rejuvenation Stored energy Domain wall

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Optimal risk Sharing for maxmin choquet Expected Utility model

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Acta mathematicae Applicatae Sinica 2024年第2期40卷 430-444页

作者： De-jian TIAN Shang-ri WU School of mathematics China University of Mining and TechnologyXuzhou 221116China

This article analyzes the Pareto optimal allocations,agreeable trades and agreeable bets under the maxmin choquet expected utility(mcEU)model.We provide several useful characterizations for Pareto optimal allocations for risk averse agents.We derive the formulation descriptions for non-existence agreeable trades or agreeable bets for risk neutral agents.We build some relationships between ex-ante stage and interim stage on agreeable trades or bets when new information arrives.

关键词： maxmin choquet expected utility model Pareto optimal allocation agreeable trade agreeable bet

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Isorhamnetin Downregulates mmP2 and mmP9 to Inhibit Development of Rheumatoid Arthritis through SRc/ERK/cREB Pathway

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chinese Journal of Integrative medicine 2024年第4期30卷 299-310页

作者： LIU Xiao-rong LI Shuo-fu mEI Wen-ya LIU Xiang-dan ZHOU ri-bao college of Pharmacy Hunan University of Chinese MedicineChangsha(410208)China Department of Orthopaedics The First Hospital of Hunan University of Chinese MedicineChangsha(410007)China

Objective To investigate the effect of isorhamnetin on the pathology of rheumatoid arthritis(RA).methods Tumor necrosis factor(TNF)-α-induced fibroblast-like synoviocytes(FLS)was exposed to additional isorhamnetin(10,20 and 40µmol/L).Overexpression vectors for matrix metalloproteinase-2(mmP2)or mmP9 or SRc were transfected to explore their roles in isorhamnetin-mediated RA-FLS function.RA-FLS viability,migration,and invasion were evaluated.moreover,a collagen-induced arthritis(cIA)rat model was established.Rats were randomly divided to sham,cIA,low-,medium-,and high-dosage groups using a random number table(n=5 in each group)and administed with normal saline or additional isorhamnetin[2,10,and 20 mg/(kg·day)]for 4 weeks,respectively.Arthritis index was calculated and synovial tissue inflammation was determined in cIA rats.The levels of mmP2,mmP9,TNF-α,interleukin-6(IL-6),and IL-1β,as well as the phosphorylation levels of SRc,extracellular regulated kinase(ERK),and cyclic adenosine monophosphate response element-binding(cREB),were detected in RA-FLS and synovial tissue.molecular docking was also used to analyze the binding of isorhamnetin to SRc.Results In in vitro studies,isorhamnetin inhibited RA-FLS viability,migration and invasion(Pmnetin downregulated the levels of mmP2,mmP9,TNF-α,IL-6,and IL-1βin RA-FLS(PmmP2 or mmP9 reversed isorhamnetin-inhibited RA-FLS migration and invasion,as well as the levels of TNF-α,IL-6,and IL-1β(Pmore,isorhamnetin bound to SRc and reduced the phosphorylation of SRc,ERK,and cREB(Pc overexpression reversed the inhibitory effect of isorhamnetin on RA-FLS viability,migration and invasion,as well as the negative regulation of mmP2 and mmP9(Pmnetin decreased arthritis index scores(Pmmation.Isorhamnetin reduced the levels of mmP2,mmP9,TNF-α,IL-6,and IL-1β,as well as the phosphorylation of SRc,ERK,and cREB in synovial tissue(P<0.05).Notably,the inhibit

关键词： rheumatoid arthritis isorhamnetin SRc/ERK/cREB matrix metalloproteinase

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Synthesis of granulated Li_(1.33)mn_(1.67)O_(4) via two antisolvent methods for lithium adsorption from gas-produced water

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chinese Journal of chemical Engineering 2024年第5期69卷 34-46页

作者： Jun Qiu Lu-ri Bao Wei Guo Ying Yang Shu-Ying Sun National Engineering Research center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China

Gas-produced water is an accompanying wastewater in the natural gas extraction process,and it is a potential liquid lithium resource that contains a considerable amount of lithium.This study investigated the feasibility of using manganese-based ion sieves to adsorb and extract lithium from gas-produced water.And we focused on the applicability of two different granulation methods,extrusion and droplet,in gas-produced water systems.Two types of H_(1.33)mn_(1.67)O_(4) particles were prepared by the extrusion method(EHmO)and the droplet method(DHmO).The porosity of DHmO was much higher than that of EHmO,and the adsorption performance of DHmO increased with the decrease of binder concentration.DHmO prepared with a binder concentration of 0.14 g·ml^(-1)exhibited the best adsorption performance in gas-produced water,and the Li^(+)adsorption capacity could reach 25.14 mg·g^(-1).In gas-produced water,the adsorption equilibrium of DHmO only took 9 h,and the adsorption process conformed to the Langmuir model and pseudo-second-order kinetic model.The pore diffusion model(PDm)could well describe its adsorption process.Besides,DHmO showed a great selectivity to Li^(+),and the selectivity order of DHmO in gas-produced water was Li^(+)>Ba^(2+)>>mg^(2+),ca^(2+),Sr^(2+)>>Na^(+)>>K^(+).After 20 cycles,the Li^(+)adsorption capacity was still higher than 17.30 mg·g^(-1),and the rate of manganese dissolution was less than 1%.

关键词： Gas-produced water Granulation Li_(1.33)mn_(1.67)O_(4)

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Optimizing piezoelectric performance of complex perovskite through increasing diversity of B-site cations

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Journal of materials Science & Technology 2024年第3期170卷 78-86页

作者： mengdi cheng Dongyan Zhang Yangxi Yan Zhimin Li Pangpang Wang ri-ichi murakami School of Advanced materials and Nanotechnology Xidian UniversityXi’an 710126China Nanomaterials Group Institute of SystemInformation Technologies and Nanotechnologies(ISIT)Fukuoka Industry-Academia Symphonicity(FiaS)4-1 KyudaishinmachiNishi-kuFukuoka 819-0388Japan School of mechanical Engineering Chengdu UniversityChengdu 610106China

Piezoelectric materials with unique properties are hugely appealing for high sensitivity sensors and ultrasonic transducers.Here,Pb(Ni_(1/3)Nb_(2/3))O_(3)-Pb(Yb_(1/2)Nb_(1/2))O_(3)-PbTiO_(3)piezoelectric system was designed and investigated in detail.The optimized piezoelectric response(d_(33)=826 pc/N,d_(33)∗=1017 pm/V)together with good temperature stability and negligible performance degradation up to 10^(6) cycles was achieved in 0.58PNN-0.10PYN-0.32PT composition.Rayleigh analysis revealed the amplification of intrinsic and extrinsic contributions in mPB region due to more spontaneous polarization orientations and an increase in chemical disorder of system after the introduction of PYN.The origin of high piezoelectric response was investigated through the combination of scanning electron microscopy and piezoresponse force microscopy.The diversity of B-site cations was shown to enhance local structural heterogeneity,weaken long-range ferroelectric ordered domains,and lower free energy barrier via the formation of nanodomain configuration that promoted polarization rotation,thereby improving piezoelectric properties of the material.Therefore,it is suggested that increasing the diversity of B-site cations is an effective strategy for achieving outstanding piezoelectric performance.

关键词： PNN-PYN-PT ceramics Piezoelectricity enhancement Relaxation behavior Domain structure

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Quantitative discrimination of surface adsorbed NOx species on ceO_(2) via spectrophotometry for ScR denitration investigation

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Journal of Rare Earths 2024年第6期42卷 1066-1072,I0003页

作者： Songil Sin Jiawei Ji Lijun cheng Zhiwen Gu chong Tan Kwangchol ri changjin Tang School of Environment Nanjing Normal UniversityNanjing210023China Department of mining Engineering Kim Chaek University of TechnologyPyongyang999093Democratic People's Republic of Korea Laboratory of mesoscopic chemistry of mOE School of Chemistry and Chemical EngineeringNanjing UniversityNanjing20023China Institute of chemical Engineering Hamhung University of Chemical EngineeringHamhungDemocratic People's Republic of Korea Jiangsu Province Engineering Research center of Environmental risk Prevention and Emergency Response Technology Nanjing210023China

ceO_(2)-based catalysts are widely investigated for selective catalytic reduction(ScR)of NO with NH3.Interaction of NO/O_(2) with ceO_(2) generally produces two surface species,i.e.,nitrates and nitrites.However,the explicit quantification of these two species is still unresolved.Herein,we reported that spectrophotometry characterization was effective in determining surface adsorbed NOx species on ceO_(2) by measuring the corresponding ions(NO_(2)-and NO_(3)^(-))dissolved in aqueous solution.Experimental results show that both nitrate(-NO_(3))and nitrite(-NO_(2))species can be quantitatively evaluated and the accuracy is verified by calibrating with NOx-TPD result.Exclusive transfer of adsorbed NOx from catalyst surface to aqueous solution is confirmed and the dissolution process can be accelerated by ultrasonic treatment.moreover,useful information related to evolution of surface NOx species under various conditions(O_(2) treatment,different adsorption temperature and duration)and over different catalysts(Fe_(2)O_(3),mnO_(2) and mnOx—ceO_(2))are provided.The result of present study demonstrates the potential of spectrophotometry for quantitative discrimination of surface NOx species on ceO_(2) and other oxide-based materials,which is conducive to mechanism analysis of ScR reaction.

关键词： Quantitative evaluation Spectrophotometry analysis Nitrate species Nitrite species ceO_(2)catalyst NH_(3)-ScR

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Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

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Avian Research 2024年第1期15卷 91-97页

作者： Nora Agh Henriett Anna Dalvári Krisztián Szabó Ivett Pipoly András Liker HUN-REN-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab Hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex chromosomes.The extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and survival.Urban areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in cities.To test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and 2019.The ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(males).However,the sex ratios of dead offspring did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study sites.These results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization Nestling mortality Sex related differences

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Experimental observation of spontaneous symmetry breaking in a quantum phase transition

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Science china(Physics,mechanics & Astronomy) 2024年第2期67卷 34-39页

作者： Wen Ning ri-Hua Zheng Jia-Hao Lu Fan Wu Zhen-Biao Yang Shi-Biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350108China Hefei National Laboratory Hefei 230088China

Spontaneous symmetry breaking(SSB)plays a central role in understanding a large variety of phenomena associated with phase transitions,such as superfluid and superconductivity.So far,the transition from a symmetric vacuum to a macroscopically ordered phase has been substantially explored.The process bridging these two distinct phases is critical to understanding how a classical world emerges from a quantum phase transition,but so far remains unexplored in experiment.We here report an experimental demonstration of such a process with a quantum Rabi model engineered with a superconducting circuit.We move the system from the normal phase to the superradiant phase featuring two symmetry-breaking field components,one of which is observed to emerge as the classical reality.The results demonstrate that the environment-induced decoherence plays a critical role in the SSB.

关键词： quantum phase transition Rabi model spontaneous symmetry breaking superconducting circuit Schrodinger cat states

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Pre-operative enhanced magnetic resonance imaging combined with clinical features predict early recurrence of hepatocellular carcinoma after radical resection

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1192-1203页

作者： Jian-Ping chen ri-Hui Yang Tian-Hui Zhang Li-An Liao Yu-Ting Guan Hai-Yang Dai Department of Intervention Meizhou People’s HospitalMeizhou 514031Guangdong ProvinceChina Department of medical Imaging Meizhou People’s HospitalMeizhou 514031Guangdong ProvinceChina Department of medical Imaging Huizhou Municipal Central HospitalHuizhou 516001Guangdong ProvinceChina

BAcKGROUND Indentifying predictive factors for postoperative recurrence of hepatocellular carcinoma(Hcc)has great significance for patient prognosis.AIm To explore the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)enhanced magnetic resonance imaging(mri)combined with clinical features in predicting early recurrence of Hcc after resection.mETHODS A total of 161 patients with pathologically confirmed Hcc were enrolled.The patients were divided into early recurrence and non-early recurrence group based on the follow-up results.The clinical,laboratory,pathological results and Gd-EOB-DTPA enhanced mri imaging features were analyzed.RESULTS Of 161 patients,73 had early recurrence and 88 were had non-early recurrence.Univariate analysis showed that patient age,gender,serum alpha-fetoprotein level,the Barcelona clinic Liver cancer stage,china liver cancer(cNLc)stage,microvascular invasion(mVI),pathological satellite focus,tumor size,tumor number,tumor boundary,tumor capsule,intratumoral necrosis,portal vein tumor thrombus,large vessel invasion,nonperipheral washout,peritumoral enhancement,hepatobiliary phase(HBP)/tumor signal intensity(SI)/peritumoral SI,HBP peritumoral low signal and peritumoral delay enhancement were significantly associated with early recurrence of Hcc after operation.multivariate logistic regression analysis showed that patient age,mVI,cNLc stage,tumor boundary and large vessel invasion were independent predictive factors.External data validation indicated that the area under the curve of the combined predictors was 0.861,suggesting that multivariate logistic regression was a reasonable predictive model for early recurrence of Hcc.cONcLUSION Gd-EOB-DTPA enhanced mri combined with clinical features would help predicting the early recurrence of Hcc after operation.

关键词： Hepatocellular carcinoma Enhanced magnetic resonance imaging microvascular invasion Hepatobiliary phase Recurrence

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