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Investigation of HO_(2) uptake mechanisms onto multiple-component ambient aerosols collected in summer and winter time in Yokohama,Japan

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Journal of Environmental Sciences 2024年第3期137卷 18-29页

作者： Jun Zhou Yukiko Fukusaki Kentaro Murano Tania Gautam Yu Bai Yoshimi Inomata Hiroaki Komatsu Mayuko Takeda Bin Yuan Min Shao Yosuke Sakamoto Yoshizumi Kajii Institute for Environmental and Climate Research Jinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation forEnvironmental Quality Guangzhou 511443China Graduate School of Global Environmental Studies Kyoto UniversityKyoto606-8501Japan Yokohama Environmental Science Research Institute Yokohama Kanagawa 221–0024Japan Department of Chemistry University of AlbertaAlbertaEdmonton T6G 2G2Canada Graduate School of Human and Environmental Studies Kyoto UniversityKyoto 606-8501Japan Kanagawa Environmental Research Center Kanagawa 254-0014Japan Center for Regional Environmental Research National Institute for Environmental StudiesIbaraki305-8506Japan

The heterogeneous loss of HO_(2)radicals onto ambient aerosols plays an important role in tropospheric chemistry.However,sparse investigation of the dominating parameters controlling the HO_(2)uptake coefficients onto ambient aerosols(γHO_(2))has largely hindered the application of the measuredγHO_(2)to the global spatial prediction.Here we induced an offine method using LFP-LIF technique to measure the kinetics of HO_(2)uptake onto ambient aerosols collected in summertime and wintertime in Yokohama city,a regional urban site near Tokyo,Japan.By controlling the dominating parameters which infuenceγHO_(2),we were able to investigate the detailed HO_(2)uptake mechanism.We characterized the chemical composition of the collected ambient aerosols,including organics,inorganics,transition metals ions,etc.and modeledγHO_(2)using different mechanisms.Results show thatγHO_(2)increased with the increase in RH,and the aerosol states(“dry”or wet/aqueous)have large effects onγHO_(2).With fixed RH and aerosol chemical composition,γHO_(2)was highly dependent on pH and inversely correlated with[HO_(2)]_0.By combing the measuredγHO_(2)values with the modeled ones,we found that both the HO_(2)self-reaction and transition metal-catalyzed reactions should be accounted for to yield a single parameterization to predictγHO_(2),and different chemical compositions may have collective effects onγHO_(2).Results may serve for extending theγHO_(2)values measured at one observation site to different environmental conditions,which will help us to achieve more accurate modeling results concerning secondary pollutant formation(i.e.,ozone).

关键词： HO_(2)uptake kinetics Offine method Impacting factors Mechanism

A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 146-156页

作者： Thong Duc Hong Minh Quang Pham Son Cong Tran Lam Quang Tran Truong Thanh Nguyen Faculty of Transportation Engineering Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam Vietnam National university Ho Chi Minh city(VNU-HCM) Ho Chi Minh City 700000Vietnam Industrial Maintenance Training Center Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam

In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems.

关键词： Dump truck Lifting mechanism Hydraulic MATLAB Simscape Kinetic dynamic analysis

Evolution of HIV/AIDS Prevention and Control Policies in China:A Grounded Theory Approach

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China CDC weekly 2024年第1期6卷 12-22页

作者： Huang Li Rui Gao Chichen Zhang School of Public Health Southern Medical UniversityGuangzhou CityGuangdong ProvinceChina School of Health Management Southern Medical UniversityGuangzhou CityGuangdong ProvinceChina Key Laboratory of Philosophy and Social Sciences of Colleges and Universities in Guangdong Province for Collaborative Innovation of Health Management Policy and Precision Health Service Southern Medical UniversityGuangzhou CityGuangdong ProvinceChina Graduate School Xi’an Jiaotong-Liverpool UniversitySuzhou CityJiangsu ProvinceChina School of Political Science and Public Administration Soochow UniversitySuzhou CityJiangsu ProvinceChina

Objective:This study aims to provide a theoretical foundation for the development and practical application of human immunodeficiency virus(HIV)/acquired immunodeficiency syndrome(AIDS)prevention and control policy systems in China by scrutinizing,analyzing,and synthesizing the evolution of Chinese policies in this domain.Methods:Utilizing grounded theory,we employed NVivo12 software to perform text content analysis,mining,and coding classification,along with visualization techniques,on policy texts sourced from Chinese government platforms,including the official website of China’s State Council.We considered four analytical dimensions—time,subject,type,and object.Results:The National Health Commission and the State Council emerged as the primary entities engaged in policymaking for HIV/AIDS in China.We identified four distinct stages in the evolution of these policies,culminating in a novel‘sun-shaped’HIV/AIDS prevention and control policy network model with an emphasis on‘knowledge,attitude,and practice’at its nucleus,which aligns with national conditions and societal progress.Furthermore,the focal groups of these policies have been dynamically refined and updated over time.Conclusions:Our findings introduce a‘sunshaped’HIV/AIDS prevention and control policy network model specific to China.We observed a conceptual policy shift towards prioritizing overall human health rather than confining the focus to disease treatment.Additionally,in light of China’s growing elderly population,the imperative to address HIV/AIDS prevention and control among older adults is an issue that warrants increased attention.

关键词： prevention HIV/AIDS policy

Spatio-temporal coupled mode theory for nonlocal metasurfaces

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Light(Science & Applications) 2024年第2期13卷 267-282页

作者： Adam Overvig Sander A.Mann Andrea Alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY10031USA Physics Program Graduate Center of the City University of New YorkNew YorkNY10016USA

Diffractive nonlocal metasurfaces have recently opened a broad range of exciting developments in nanophotonics research and applications,leveraging spatially extended—yet locally patterned—resonant modes to control light with new degrees of freedom.While conventional grating responses are elegantly captured by temporal coupled mode theory,current approaches are not well equipped to capture the arbitrary spatial response observed in the nascent field of nonlocal metasurfaces.Here,we introduce spatio-temporal coupled mode theory(STCMT),capable of elegantly capturing the key features of the resonant response of wavefront-shaping nonlocal metasurfaces.This framework can quantitatively guide nonlocal metasurface design while maintaining compatibility with local metasurface frameworks,making it a powerful tool to rationally design and optimize a broad class of ultrathin optical components.We validate this STCMT framework against full-wave simulations of various nonlocal metasurfaces,demonstrating that this tool offers a powerful semi-analytical framework to understand and model the physics and functionality of these devices,without the need for computationally intense full-wave simulations.We also discuss how this model may shed physical insights into nonlocal phenomena in photonics and the functionality of the resulting devices.As a relevant example,we showcase STCMT’s flexibility by applying it to study and rapidly prototype nonlocal metasurfaces that spatially shape thermal emission.

关键词： theory resonant spatially

The Role of Childhood Circumstances in Healthy Aging Inequalities Among Older Adults—China,2011–2020

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China CDC weekly 2024年第11期6卷 208-212,I0004-I0007页

作者： Peng Nie Xili Lin Lanlin Ding School of Economics and Finance Xi’an Jiaotong UniversityXi’an CityShaanxi ProvinceChina Global Health Institute Xi’an Jiaotong University Health Science CenterXi’an CityShaanxi ProvinceChina National School of Development Peking UniversityBeijingChina

What is already known about this topic?Addressing health disparities is a worldwide priority,with a well-established acknowledgment of the influence of childhood circumstances on these discrepancies.In China,particularly among the elderly,health inequalities are a notable concern.What is added by this report?The inequality in healthy aging has increased from 2011 to 2020,both in general and concerning childhood factors.Nevertheless,the impact of early-life healthcare access and parental health behaviors on healthy aging gaps has reduced among older adults in better health within the top segment of healthy aging.What are the implications for public health practice?Efforts towards reducing regional health disparities and improving healthcare access for children,along with promoting the health and well-being of parents,especially in economically disadvantaged households,are crucial policy considerations.

关键词： ledgment inequalities circumstances

Genomics-driven derivatization of the bioactive fungal sesterterpenoid variecolin:Creation of an unnatural analogue with improved anticancer properties

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Acta Pharmaceutica Sinica B 2024年第1期14卷 421-432页

作者： Dexiu Yan Jemma Arakelyan Teng Wan Ritvik Raina Tsz Ki Chan Dohyun Ahn Vladimir Kushnarev Tsz Kiu Cheung Ho Ching Chan Inseo Choi Pui Yi Ho Feijun Hu Yujeong Kim Hill Lam Lau Ying Lo Law Chi Seng Leung Chun Yin Tong Kai Kap Wong Wing Lam Yim Nikolay S.Karnaukhov Richard Y.C.Kong Maria V.Babak Yudai Matsuda Department of Chemistry City University of Hong KongHong Kong SARChina iGEM Team“VarieCure” City University of Hong KongHong Kong SARChina Department of Biomedical Engineering City University of Hong KongHong Kong SARChina Moscow Clinical Research Center Named After A.S.Loginov Moscow 111123Russian Federation

A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin(1)and variecolactone(2)was identified in Aspergillus aculeatus ATCC 16872.Heterologous production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 VrcB.Intriguingly,the replacement of VrcB with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues(5-7).Analysis of the compounds’anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities,5 was associated with significantly reduced toxic side effects in cancer-bearing mice,indicating its potentially broader therapeutic window.Our study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.

关键词： Animal studies Anticancer properties Biosynthesis Natural products Sesterterpenoids Synthetic biology Terpene synthases Variecolin

Wettability Gradient-Induced Diode:MXene-Engineered Membrane for Passive-Evaporative Cooling

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Nano-Micro Letters 2024年第8期16卷 382-397页

作者： Leqi Lei Shuo Meng Yifan Si Shuo Shi Hanbai Wu Jieqiong Yang Jinlian Hu Department of Biomedical Engineering City University of Hong KongHong Kong S.A.R 999077China

Thermoregulatory textiles,leveraging high-emissivity structural materials,have arisen as a promising candidate for personal cooling management;however,their advancement has been hindered by the underperformed water moisture transportation capacity,which impacts on their thermophysiological comfort.Herein,we designed a wettability-gradient-induced-diode(WGID)membrane achieving by MXene-engineered electrospun technology,which could facilitate heat dissipation and moisture-wicking transportation.As a result,the obtained WGID membrane could obtain a cooling temperature of 1.5℃ in the“dry”state,and 7.1℃ in the“wet”state,which was ascribed to its high emissivity of 96.40%in the MIR range,superior thermal conductivity of 0.3349 W m^(-1) K^(-1)(based on radiation-and conduction-controlled mechanisms),and unidirectional moisture transportation property.The proposed design offers an approach for meticulously engineering electrospun membranes with enhanced heat dissipation and moisture transportation,thereby paving the way for developing more efficient and comfortable thermoregulatory textiles in a high-humidity microenvironment.

关键词： Passive-evaporative cooling MXene Electrospun membrane Wettability gradient Diode

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván Y.Hernández-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air pollution.In Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is enhanced.Here,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central Mexico.The studied period covers the lockdown phases 2 and 3,and the first month of the New Normal.We applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the Megalopolis.The results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed NO_(x)-limited and VOC-limited regional regimes.This contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency estimations.Given the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor Separation Process Analysis

Quantization and Event-Triggered Policy Design for Encrypted Networked Control

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 946-955页

作者： Yongxia Shi Ehsan Nekouei the Department of Electrical Engineering City University of Hong KongHong KongChina

This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-triggered strategy.Due to the fact that only integers can work in the Pailler cryptosystem,both the real-valued control gain and system state need to be first quantized before encryption.This is dramatically different from the existing quantized control methods,where only the quantization of a single value,e.g.,the control input or the system state,is considered.To handle this issue,static and dynamic quantization policies are presented,which achieve the desired integer conversions and guarantee asymptotic convergence of the quantized system state to the equilibrium.Then,the quantized system state is encrypted and sent to the controller when the triggering condition,specified by a state-based event-triggered strategy,is satisfied.By doing so,not only the security and confidentiality of data transmitted over the communication network are protected,but also the ciphertext expansion phenomenon can be relieved.Additionally,by tactfully designing the quantization sensitivities and triggering error,the proposed event-driven encrypted control framework ensures the asymptotic stability of the overall closedloop system.Finally,a simulation example of the secure motion control for an inverted pendulum cart system is presented to evaluate the effectiveness of the theoretical results.

关键词： Cyber-security encrypted control event-triggered control(ETC) networked control systems(NCSs) semi-homomorphic encryption