科研成果

2021
Salvador CMG, Tang R, Priestley M, Li L, Tsiligiannis E, Le Breton M, Zhu W, Zeng L, Wang H, Yu Y, et al. Ambient nitro-aromatic compounds-biomass burning versus secondary formation in rural China. Atmospheric Chemistry and PhysicsAtmospheric Chemistry and PhysicsAtmos. Chem. Phys. 2021;21:1389-1406.Abstract
Nitro-aromatic compounds (NACs) were measured hourly at a rural site in China during wintertime to monitor the changes due to local and regional impacts of biomass burning (BB). Concurrent and continuous measurements of the concentrations of 16 NACs in the gas and particle phases were performed with a time-of-flight chemical ionization mass spectrometer (CIMS) equipped with a Filter Inlet for Gases and AEROsols (FIGAERO) unit using iodide as the reagent ion. NACs accounted for <2% of the mass concentration of organic matter (OM) and total particulate matter (PM), but the total particle mass concentrations of these compounds can reach as high as 1000 ngm-3 (299 ngm-3 avg), suggesting that they may contribute significantly to the radiative forcing effects of atmospheric particles. Levels of gas-phase NACs were highest during the daytime (15:00-16:00 local time, LT), with a smaller nighttime peak around 20:00 LT. Box-model simulations showed that this occurred because the rate of NAC production from gas-phase sources exceeded the rate of loss, which occurred mainly via the OH reaction and to a lesser degree via photolysis. Data gathered during extended periods with high contributions from primary BB sources (resulting in 40 %-60% increases in NAC concentrations) were used to characterize individual NACs with respect to gas-particle partitioning and the contributions of regional secondary processes (i.e. photochemical smog). On days without extensive BB, secondary formation was the dominant source of NACs, and NAC levels correlated strongly with the ambient ozone concentration. Analyses of individual NACs in the regionally aged plumes sampled on these days allowed precursors such as phenol and catechol to be linked to their NAC derivatives (i.e. nitrophenol and nitrocatechol). Correlation analysis using the high time resolution data and box-model simulation results constrained the relationships between these compounds and demonstrated the contribution of secondary formation processes. Furthermore, 13 of 16 NACS were classified according to primary or secondary formation process. Primary emission was the dominant source (accounting for 60 %- 70% of the measured concentrations) of 5 of the 16 studied NACs, but secondary formation was also a significant source. Photochemical smog thus has important effects on brown carbon levels even during wintertime periods dominated by primary air pollution in rural China. © Author(s) 2021.
Xie K. Ambivalent Fatherland: The Chinese National Salvation Movement in Malaya and Java, 1937–41. Journal of Southeast Asian Studies [Internet]. 2021;52(4):677-700. 访问链接Abstract
China's resistance to Japanese aggression escalated into a full-scale war in 1937. The continuously deteriorating situation stimulated the rise of Chinese nationalism in the diaspora communities worldwide. The Japanese invasion of China, accompanied by the emergence of the National Salvation Movement (NSM) in Southeast Asia, provided the overseas Chinese with a rare opportunity to re-examine their ‘Chineseness’, as well as their relationships with the colonial states and the increasingly self-aware indigenous populations. This research problematises traditional approaches that tend to regard the NSM as primarily driven by Chinese patriotism. Juxtaposing Malaya and Java at the same historical moment, the article argues that the emergence of the NSM was more than just a natural result of the rising Chinese nationalism. Local politics and the shifting political orientations of overseas Chinese communities also profoundly shaped how the NSM played out in different colonial states.
Abudurousu A, Li S. Analysis of the Health Needs of Chinese Empty Nesters and Feasible Countermeasures, in 2021 Aging and Health Informatics Conference (AHIC). https://sites.utexas.edu/ahic/; 2021.
Lin H, Li S*. Analysis Of User Social Support Network In Online Tumor Community. Data And Information Management. 2021;5(1):184-194.
Sun X, Guan T, Xue T, Fan C, Yang M, Meng Y, Zhang T, Jiangtulu B, Wu F, Li J. Analysis on action tracking reports of covid-19 informs control strategies and vaccine delivery in post-pandemic era. medRxiv. 2021.
Wan Z, Anwar A, Hsiao Y-S, Jia T, Reddi VJ, Raychowdhury A. Analyzing and improving fault tolerance of learning-based navigation system, in Design Automation Conference (DAC).; 2021.
Arbitrary degree distribution networks withperturbations. AIP Advance [Internet]. 2021. 访问链接
Chen W, Wen D. Archaeal and bacterial communities assembly and co-occurrence networks in subtropical mangrove sediments under Spartina alterniflora invasion. Environmental Microbiome [Internet]. 2021;16(1):10. 访问链接Abstract
Background Mangrove ecosystems are vulnerable due to the exotic Spartina alterniflora (S. alterniflora) invasion in China. However, little is known about mangrove sediment microbial community assembly processes and interactions under S. alterniflora invasion. Here, we investigated the assembly processes and co-occurrence networks of the archaeal and bacterial communities under S. alterniflora invasion along the coastlines of Fujian province, southeast China. Results Assembly of overall archaeal and bacterial communities was driven predominantly by stochastic processes, and the relative role of stochasticity was stronger for bacteria than archaea. Co-occurrence network analyses showed that the network structure of bacteria was more complex than that of the archaea. The keystone taxa often had low relative abundances (conditionally rare taxa), suggesting low abundance taxa may significantly contribute to network stability. Moreover, S. alterniflora invasion increased bacterial and archaeal drift process (part of stochastic processes), and improved archaeal network complexity and stability, but decreased the network complexity and stability of bacteria. This could be attributed to S. alterniflora invasion influenced microbial communities diversity and dispersal ability, as well as soil environmental conditions. Conclusions This study fills a gap in the community assembly and co-occurrence patterns of both archaea and bacteria in mangrove ecosystem under S. alterniflora invasion. Thereby provides new insights of the plant invasion on mangrove microbial biogeographic distribution and co-occurrence network patterns.
Han H, Zhang D, Zhu Z, Wei R, Xiao X, Wang X, Liu Y, Ma Y*, Zhao D*. Aromatic Stacking Mediated Spin-Spin Coupling in Cyclophane-Assembled Diradicals. J. Am. Chem. Soc. [Internet]. 2021;143:17690-17700. [Read Online] Abstract
To investigate the capability of pi-pi stacking motifs to enable spin-spin coupling, we designed and synthesized three pairs of regio-isomers featuring two radical moieties joined by a [2.2]paracyclophane (CP) unit. By fusing indeno units to CP, two partially stacked fluorene radicals are covalently linked, exhibiting evident antiferromagnetic (AFM) coupling regardless of the orientation of two spins. Remarkably, while possessing high diradical indices of 0.8 and 0.9, the two molecules demonstrate good air stability by virtue of their singlet ground state. Single crystals help unravel the structural basis of their AFM coupling behaviors. When two radical centers are arranged at the pseudometa-positions around CP, the face-to-face stacked phenylene rings intrinsically confer orbital interactions that promote AFM coupling. On the other hand, if two radicals are directed in the pseudopara-orientation, significant orbital overlapping is observed between the radical centers (i.e., C9 of fluorene) and the aromatic carbons laid on the side, rendering AFM coupling between the two spins. In contrast, when two fluorene radicals are tethered to CP via C9 through a single C-C bond, ferromagnetic (FM) coupling is manifested by both diradical isomers featuring pseudometa- and pseudopara-connectivity. With minimal spin distributed on CP and thus limited contribution from pi-pi stacking, their spin-spin coupling properties are more similar to a pair of nitroxide diradical analogues, in which the two spins are dominantly coupled via through-space interactions. From these results, important conclusions are elucidated such as that although through-space interactions may confer FM coupling, with weakened strength shown by PAH radicals due to their lower polarity, face-to-face stacked p-frameworks tend to induce AFM coupling, because favorable orbital interactions are readily achieved by PAH systems hosting delocalized spins that are capable of adopting varied stacking motifs.  
Yu Y, Ginoux P. Assessing the contribution of the ENSO and MJO to Australian dust activity based on satellite-and ground-based observations. Atmospheric Chemistry and Physics. 2021;21:8511–8530.
Liu J, Li X, Tan Z, Wang W, Yang Y, Zhu Y, Yang S, Song M, Chen S, Wang H, et al. Assessing the Ratios of Formaldehyde and Glyoxal to NO 2 as Indicators of O 3 –NO x –VOC Sensitivity. Environmental Science & Technology. 2021;55.
Quainoo EA, Asamoah DB, Adams F, Opoku E, Rahman MS. Assessment in Chinese Higher Education : Chinese Students ' Conception of A ssessment in Chinese Higher Education : Chinese Students ' Conception of Assessment. International journal for innovative research in multidisciplinary field. 2021;7(2):232-238.Abstract
Information about students’ learning is necessary for educational decision making. Therefore,  classroom assessment, comprehended as the procedure in which students’ reactions to spontaneous activities are  used to draw inferences about their knowledge and skills assumes a significant role in education. In higher  education, students’ learning is more impacted by their originations of the instructive condition than by the real  instructive practices. In China, which has a long history of examination-oriented education, an assessment reform  in basic and higher education was kicked off by the Ministry of Education as part of the New Curriculum Reform  in 2001. This paper reviews literature on students’ upheld conceptions of assessment and then reports a study into  Chinese students’ conception of assessment. Literature reviewed revealed that students conceive of assessment in  at least four major ways (i.e., assessment makes students accountable; assessment is irrelevant because it is bad or unfair; assessment improves the quality of learning; and assessment is enjoyable). The findings of the study  also indicated that students conceive assessment as being for improvement of learning and assigning grades.
Guo J, Zhou Y, Wang Y, Zhang B, Zhang J. Assessment of internal exposure to methylsiloxanes in children and associated non-dietary exposure risk. Environment International [Internet]. 2021;154. 访问链接Abstract
Methylsiloxanes (MSs) are a significant source of indoor environmental pollution due to their high production level and widespread application, and pose a potential health risk. Given the special vulnerability of children to environmental contaminants, assessment of indoor MSs exposure in children is quite essential. In this study, we assessed internal exposure doses and external exposure levels of MSs in children from industrial and residential areas in southwestern China. Indoor air, indoor dust, and personal care product (PCP) samples were collected to evaluate indoor non-dietary MSs exposure in children through various pathways. The concentrations of MSs in indoor environments of industrial areas were approximately one to four orders of magnitude higher than those of residential areas. Sun protection products contained the highest concentrations of MSs. Relatively high levels of cyclic methylsiloxanes (CMSs) were found in plasma of children from industrial areas, which were one to two orders of magnitude higher than those in children from residential areas. The highest MSs levels in plasma were detected in infants (0–1 year), with values of 1.4 × 102 ng/mL and 1.3 × 102 ng/mL for CMSs (D4–D6) and linear methylsiloxanes (LMSs) (L5–L16), respectively. The internal exposure dose of infants in residential areas is driven by major unknown sources of MSs. The average daily doses via inhalation and dust ingestion in children from industrial areas were one to three orders of magnitude higher than in those from residential areas, indicating that these children should be considered a highly exposed population. Inhalation and dust ingestion were both major exposure pathways to MSs for children of all age groups in industrial areas, whereas dermal absorption from PCPs was the predominant exposure pathway for children of all age groups in residential areas (except for infants). Although the exposure risk to D4 and D5 was at an acceptable level for all children studied, the total daily exposure doses of these two cyclic compounds via inhalation for infants in the industrial areas was near the chronic reference dose. Meanwhile, MSs may accumulate in infant plasma within a short period of time (&lt;6 months). Therefore, infants should be the focus of greater attention in future research. As indoor environments may pose high risks for infants in industrial areas, they should be the focus of future research. © 2021
Jia Z, Xu S, Zhang Z, Cheng Z, Han H, Xu H, Wang M, Zhang H, Zhou Y, Zhou Z. Association between Mental Health and Community Support in Lockdown Communities during the COVID-19 Pandemic: Evidence from Rural China. Journal of Rural Studies [Internet]. 2021;82:87-97. 访问链接Abstract
Governments worldwide have taken unprecedented social distancing and community lockdown measures to halt the COVID-19 epidemic, leaving millions of people restrained in locked-down communities and their mental well-being at risk. This study examines Chinese rural residents' mental health risk under emergency lockdown during the COVID-19 pandemic. It investigates how the environmental, socioeconomic, and behavioral dimensions of community support affect mental health in this emergency context. We also explore whether community support's effectiveness depends on the strictness of lockdown measures implemented and the level of individual perceived COVID-19 infection risk. We collect self-reported mental health risk, community support, and demographics information through a cross-sectional survey of 3892 Chinese rural residents living in small towns and villages. Ordinary least square regressions are employed to estimate the psychological effects of community support. The results suggest that the COVID-19 epidemic and lockdown policies negatively affect psychological well-being, especially for rural females. The capacity for community production has the largest impact on reducing mental health risks, followed by the stability of basic medical services, community cohesion, housing condition, the stability of communications and transportation supply, and the eco-environment. The effectiveness of different community support dimensions depends on the level of lockdown policy implemented and the levels of one's perceived risk of COVID-19 infection. Our study stresses the psychological significance of a healthy living environment, resilient infrastructure and public service system, and community production capacity during the lockdown in rural towns and villages.
Zhang Q, Zhao X*, Liu H, Yu N, Li D. Association between the metabolic syndrome and muscle weakness among Chinese older adults: results from the China Health and Retirement Longitudinal Study. Geriatric Nursing. 2021;42(6):1415-1421.
Hu X, Yan M, He L, Qiu X, Zhang J, Zhang Y, Mo J, Day DB, Xiang J, Gong J. Associations between time-weighted personal air pollution exposure and amino acid metabolism in healthy adults. Environment InternationalEnvironment International. 2021;156.
He L, Hu X, Day DB, Yan M, Teng Y, Liu X, Yan E, Xiang J, Qiu X, Mo J, et al. The associations of nitrated polycyclic aromatic hydrocarbon exposures with plasma glucose and amino acids*. Environmental PollutionEnvironmental Pollution. 2021;289.
Zheng J, Brose U, Gravel D, Gauzens B, Luo M, Wang S. Asymmetric foraging lowers the trophic level and omnivory in natural food webs. Journal of Animal Ecology. 2021.
Dai P*, Hu K, Wu X, Xing H, Yu Z. Asynchronous Deep Reinforcement Learning for Data-Driven Task Offloading in MEC-Empowered Vehicular Networks, in IEEE International Conference on Computer Communications (INFOCOM).; 2021:1-10. PDFAbstract
Mobile edge computing (MEC) has been an effective paradigm to support real-time computation-intensive vehicular applications. However, due to highly dynamic vehicular topology, these existing centralized-based or distributed-based scheduling algorithms requiring high communication overhead, are not suitable for task offloading in vehicular networks. Therefore, we investigate a novel service scenario of MEC-based vehicular crowdsourcing, where each MEC server is an independent agent and responsible for making scheduling of processing traffic data sensed by crowdsourcing vehicles. On this basis, we formulate a data-driven task offloading problem by jointly optimizing offloading decision and bandwidth/computation resource allocation, and renting cost of heterogeneous servers, such as powerful vehicles, MEC servers and cloud, which is a mixed-integer programming problem and NP-hard. To reduce high time-complexity, we propose the solution in two stages. First, we design an asynchronous deep Q-learning to determine offloading decision, which achieves fast convergence by training the local DQN model at each agent in parallel and uploading for global model update asynchronously. Second, we decompose the remaining resource allocation problem into several independent subproblems and derive optimal analytic formula based on convex theory. Lastly, we build a simulation model and conduct comprehensive simulation, which demonstrates the superiority of the proposed algorithm.
Liying Yi, Jing Wu MAWXXFBYYLDGXZJHU. The atmospheric concentrations and emissions of major halocarbons in China during 2009–2019. Environmental Pollution [Internet]. 2021;284. 访问链接Abstract
Due to the characteristics of ozone-depleting and high global warming potential, chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) have been restricted by the Montreal Pro- tocol and its amendments over the world. Considering that China is one of the main contributors to the emission of halocarbons, a long-term atmospheric observation on major substances including CFC-11 (CCl3F), CFC-12 (CCl2F2), HCFC-22 (CHClF2), HCFC-141b (CH3CCl2F), HCFC-142b (CH3CClF2) and HFC-134a (CH2FCF3) was conducted in five cities (Beijing, Hangzhou, Guangzhou, Lanzhou and Chengdu) of China during 2009–2019. The atmospheric concentrations of CFC-11, CFC-12, HCFC-141b and HCFC-142b all showed declining trends on the whole while those of HCFC-22 and HFC-134a were opposite. A paired sample t-test showed that the ambient mixing ratios of HCFC-22 and HFC-134a in cities were 41.9% and 25.7% higher on average than those in sub- urban areas, respectively, while the other substances did not show significant regional differences. The annual emissions of halocarbons were calculated using an interspecies correlation method and the results were generally consistent with the published estimates. Discrepancies between bottom-up inventories and the estimates in this study for CFCs emissions were found. Among the most consumed ozone depleting substances (ODSs) in China, CFCs accounted for 75.1% of the ozone depletion potential (ODP)-weighted emissions while HCFCs contributed a larger proportion (58.6%) of CO2-equivalent emissions in 2019. China’s emissions of HCFC-141b and HCFC-142b contributed the most to the global emission (17.8%–48.0%). The elimination of HCFCs in China will have a crucial impact on the HCFCs phase-out in the world.

Pages