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Polarization in ■ decays

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Chinese Physics C 2020年第1期44卷 11-15页

作者： tong-zhu Han Rong-Gang Ping Tao Luo Guang-Zhi Xu Key Laboratory of Nuclear Physics and Ion-beam Application(MOE)and Institute of Modern Physics Fudan UniversityShanghai 200443China Physics department Liaoning UniversityShenyang 110036China Institute of High Energy Physics Chinese Academy of SciencesP.O.Box 918(1)Beijing 100049China University of Chinese Academy of Science Beijing 100049China

Measurements of decay asymmetry parameters of charmed baryons,e.g.,■,provide more data to test the W-emission and W-exchange mechanisms controlled by strong and weak *** advantage of the spin polarization in charmed baryon decays,we investigate the possibility to measure weak decay asymmetry parameters in thee^+e^-→■ *** analyze the transverse polarization spontaneously produced in this process and the spin transfer in the subsequent■ *** sensitivity to measure the asymmetry parameters is estimated for the decay■→■.

关键词： transverse polarization asymmetry parameters spin charmed baryon decays

Using X-ray computed tomography and micro-Raman spectrometry to measure individual particle surface area, volume, and morphology towards investigating atmospheric heterogeneous reactions

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Journal of Environmental Sciences 2018年第7期30卷 23-32页

作者： Mingjin Wang Nan Zheng tong zhu Jing Shang Ting Yu Xiaojuan Song Defeng Zhao Yong Guan Yangchao Tian BIC-ESAT and SKL-ESPCl College of Environmental Sciences and Engineering Peking University Beijing 100871 China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029 China

Heterogeneous reactions on the aerosol particle surface in the atmosphere play important roles in air pollution, climate change, and global biogeochemical cycles. However, the reported uptake coefficients of heterogeneous reactions usually have large variations and may not be relevant to real atmospheric conditions. One of the major reasons for this is the use of bulk samples in laboratory experiments, while particles in the atmosphere are suspended individually. A number of technologies have been developed recently to study heterogeneous reactions on the surfaces of individual particles. Precise measurements on the reactive surface area, volume, and morphology of individual particles are necessary for calculating the uptake coefficient, quantifying reactants and products, and understanding the reaction mechanism better. In this study, for the first time we used synchrotron radiation X-ray computed tomography（XCT） and micro-Raman spectrometry to measure individual CaCO_3 particle morphology, with sizes ranging from 3.5–6.5 μm. Particle surface area and volume were calculated using a reconstruction method based on software threedimensional（3-D） rendering. The XCT was first validated with high-resolution fieldemission scanning electron microscopy（FE-SEM） to acquire accurate CaCO_3 particle surface area and volume estimates. Our results showed an average difference of only 6.1% in surface area and 3.2% in volume measured either by micro-Raman spectrometry or X-ray tomography. X-ray tomography and FE-SEM can provide more morphological details of individual Ca CO3 particles than micro-Raman spectrometry. This study demonstrated that X-ray computed tomography and micro-Raman spectrometry can precisely measure the surface area, volume, and morphology of an individual particle.

关键词： Heterogeneous reactions Individual CaCO3 particle Micro-Raman spectrometry Synchrotron radiation X-ray computed tomography Morphology Surface area Volume

Traceless enzymatic protein synthesis without ligation sites constraint

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National Science Review 2022年第5期9卷 108-118页

作者： Ruifeng Li Marcel Schmidt tong zhu Xinyu Yang Jing Feng Yu'e Tian Yinglu Cui Timo Nuijens Bian Wu CAS Key Laboratory of Microbial Physiological and Metabolic Engineering State Key Laboratory of Microbial ResourcesInstitute of Microbiology Chinese Academy of Sciences University of Chinese Academy of Sciences Fresenius Kabi iPSUM I&D Center EnzyPep B.V.

Protein synthesis and semisynthesis offer immense promise for life sciences and have impacted pharmaceutical *** absence of a generally applicable method for traceless peptide conjugation with a flexible choice of junction sites remains a bottleneck for accessing many important synthetic targets,*** we introduce the PALME(protein activation and ligation with multiple enzymes) platform designed for sequence-unconstrained synthesis and modification of *** upstream activating modules accept and process easily accessible synthetic peptides and recombinant proteins,avoiding the challenges associated with preparation and manipulation of activated peptide ***,the downstream coupling module provides comprehensive solutions for sequential peptide condensation,cyclization and protein N/C-terminal or internal *** practical utility of this methodology is demonstrated by synthesizing a series of bioactive targets ranging from pharmaceutical ingredients to synthetically challenging *** modular PALME platform exhibits unprecedentedly broad accessibility for traceless protein synthesis and functionalization,and holds enormous potential to extend the scope of protein chemistry and synthetic biology.

关键词： protein synthesis traceless peptide ligation biocatalysis synthetic biology chemical biology

Health benefits from the rapid reduction in ambient exposure to air pollutants after China's clean air actions:progress in efficacy and geographic equality

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National Science Review 2024年第2期11卷 103-113页

作者： Tao Xue Ruohan Wang Meng Wang Yanying Wang Dan tong Xia Meng Conghong Huang Siqi Ai Fangzhou Li Jingyuan Cao Mingkun tong Xueqiu Ni Hengyi Liu Jianyu Deng Hong Lu Wei Wan Jicheng Gong Shiqiu Zhang tong zhu Institute of Reproductive and Child Health National Health Commission Key Laboratory of Reproductive Health/Department of Epidemiology and Biostatistics Ministry of Education Key Laboratory of Epidemiology of Major Diseases(PKU) School of Public Health Peking University Health Science Centre State Environmental Protection Key Laboratory of Atmospheric Exposure and Health Risk Management and Center for Environment and Health Peking University Advanced Institute of Information Technology Peking University Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at Buffalo State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University Department of Earth System Science Tsinghua University School of Public Health Key Laboratory of Public Health Safety of the Ministry of Education and Key Laboratory of Health Technology Assessment of the Ministry of HealthFudan University College of Land Management Nanjing Agricultural University National&Local Joint Engineering Research Center for Rural Land Resources Use and Consolidation Clean Air Asia

Clean air actions （CAAs） in China have been linked to considerable benefits in public ***,whether the beneficial effects of CAAs are equally distributed geographically is *** high-resolution maps of the distributions of major air pollutants (fine particulate matter[PM2.5]and ozone[O3]) and population,we aimed to track spatiotemporal changes in health impacts from,and geographic inequality embedded in,the reduced exposures to PM2.5and O3from 2013 to *** used a method established by the Global Burden of Diseases *** analyzing the changes in loss of life expectancy（LLE） attributable to PM2.5and O3,we calculated the gain of life expectancy （GLE） to quantify the health benefits of the air-quality ***,we assessed the geographic inequality embedded in the GLE using the Gini index （GI）.Based on risk assessments of PM2.5and O3,during the first stage of CAAs（2013 to 2017）,the mean GLE was 1.87 *** of the sum of the GLE was disproportionally distributed in about one quarter of the population exposed （GI 0.44）.During the second stage of CAAs（2017 to 2020）,the mean GLE increased to 3.94 months and geographic inequality decreased （GI 0.18）.According to our assessments,CAAs were enhanced,from the first to second stages,in terms of not only preventing premature mortality but also ameliorating health *** enhancements were related to increased sensitivity to the health effects of air pollution and synergic control of PM2.5and *** findings will contribute to optimizing future CAAs.

关键词： clean air action public health inequality fine particulate matter ozone

Heterogeneous reactions on the surface of fine particles in the atmosphere

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Chinese Science Bulletin 2003年第21期48卷 2267-2276页

作者： DING Jie & zhu tong State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences, Peking University, Beijing 100871, China Correspondence should be addressed to zhu tong (e-mail:tzhu@ ***) State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences Peking University Beijing China

Fine particles play an important role in the atmosphere. Research on heterogeneous reactions on the surface of fine particles is one of the frontier areas of atmospheric science. In this paper, physical and chemical characteristics of fine particles in the atmosphere and the interactions between trace gases and fine particles are described, methods used in heterogeneous reactions research are discussed in detail, progress in the study of heterogeneous reactions on the surface of fine particles in the atmosphere is summarized, existing important questions are pointed out and future research directions are suggested.

关键词：细微颗粒大气科学多相反应空气动力学

Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer over a suburb farmland in Beijing

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Frontiers of Environmental Science & Engineering 2007年第2期1卷 159-165页

作者： ZHAO Peng zhu tong LIANG Baosheng HU Min KANG Ling GONG Jicheng State Key Joint Laboratory of Environment Simulation and Pollution Control College of Environmental SciencesPeking UniversityBeijing 100871China

Agricultural activity is one of the most important sources of aerosol *** understand the mass distribu-tion and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beijing,particle samples were collected using a microorifice uniform deposit impactor(MOUDI)in the summer of 2004 in a suburb vege-table *** distribution of the particles and their inor-ganic water-soluble ions in the diameter range of 0.18-18 mm were *** dominant fine particle ions were SO_(4)^(2−),NO^(3−),and NH_(4)^(+).The association of day-to-day variation of the concentration of these ions with temperature,humidity,and solar radiation suggested that they are formed by the reac-tion of NH_(3) released from the vegetable field with the acid species produced from photochemical *** particle K+is likely from vegetation emission and biomass *** particles like Ca^(2+),Mg^(2+),NO_(3)^(−),and SO_(4)^(2−)are sug-gested to come from the mechanical process by which the soil particle entered the atmosphere,and from the reaction of the acid species at the surface of the soil *** results show that fertilizer and soil are important factors determining the aerosol particle over agricultural fields,and vegetable fields in suburban Beijing contribute significantly to the aerosol particle.

关键词： mass size distribution coarse particle fine particle source

Sequencing and comparison of the Rickettsia genomes from the whitefly Bemisia tabaci Middle East Asia Minor I

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Insect Science 2016年第4期23卷 531-542页

作者： Dan-tong zhu Wen-Qiang Xia Qiong Rao Shu-Sheng Liu Murad Ghanim Xiao-Wei Wang Ministry of Agriculture Key Laboratory of Agricultural Entomology Institute of Insect Sciences Zhejiang University Hangzhou China Department of Entomology Agricultural Research Organization The Volcani Center Bet Dagan Israel School of Agriculture and Food Science Zhejiang Agriculture and Forestry University Lin'an Hangzhou China

The whitefly, Bemisia tabaci, harbors the primary symbiont ＇Candidatus Portiera aleyrodidarum＇ and a variety of secondary symbionts. Among these secondary symbionts, Rickettsia is the only one that can be detected both inside and outside the bacteriomes. Infection with Rickettsia has been reported to influence several aspects of the whitefly biology, such as fitness, sex ratio, virus transmission and resistance to pesticides. However, mechanisms underlying these differences remain unclear, largely due to the lack of genomic information of Rickettsia. In this study, we sequenced the genome of two Rickettsia strains isolated from the Middle East Asia Minor 1 （MEAM1） species of the B. tabaci complex in China and Israel. Both Rickettsia genomes were of high coding den- sity and AT-rich, containing more than 1000 coding sequences, much larger than that of the coexisted primary symbiont, Portiera. Moreover, the two Rickettsia strains isolated from China and Israel shared most of the genes with 100% identity and only nine genes showed sequence differences. The phylogenetic analysis using orthologs shared in the genus, inferred the proximity of Rickettsia in MEAM1 and Rickettsia bellii. Functional analysis revealed that Rickettsia was unable to synthesize amino acids required for complementing the whitefly nutrition. Besides, a type IV secretion system and a number of virulence- related genes were detected in the Rickettsia genome. The presence of virulence-related genes might benefit the symbiotic life of the bacteria, and hint on potential effects of Rickettsia on whiteflies. The genome sequences of Rickettsia provided a basis for further understanding the function of Rickettsia in whiteflies.

关键词： Bemisia tabaci comparison endosymbiont genome Rickettsia symbiosis

Cost-Effective Control of Ground-Level Ozone Pollution in and around Beijing

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Chinese Journal of Population,Resources and Environment 2012年第2期10卷 101-109页

作者： Xie Xuxuan Zhang Shiqiu Xu Jianhua Wu Dan zhu tong College of Environmental Sciences and Engineering Peking UniversityBeijing 100871China

Ground level ozone pollution has become a significant air pollution problem in Beijing. Because of the complex way in which ozone is formed, it is difficult for policy makers to identify optimal control options on a cost-effective basis. This paper identi-fies and assesses a range of options for addressing this problem. We apply the Ambient Least Cost Model and compare the eco-nomic costs of control options, then recommend the most effective sequence to realize pollution control at the lowest cost. The study finds that installing of Stage II gasoline vapor recovery system at Beijing's 1446 gasoline stations would be the most cost-effective option. Overall, options to reduce ozone pollution by cutting ve-hicular emissions are much more cost-effective than options to "clean up" coal-fired power plants.

关键词： ground level ozone pollution Ambient Least CostModel Beijing

Development and transdifferentiation into inner hair cells require Tbx2

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National Science Review 2022年第12期9卷 135-148页

作者： Zhenghong Bi Xiang Li Minhui Ren Yunpeng Gu tong zhu Shuting Li Guangqin Wang Suhong Sun Yuwei Sun Zhiyong Liu Institute of Neuroscience State Key Laboratory of Neuroscience CAS Center for Excellence in Brain Science and Intelligence Technology Chinese Academy of Sciences University of Chinese Academy of Sciences Shanghai Center for Brain Science and Brain-Inspired Intelligence Technology

Atohl is essential for the development of both outer hair cells(OHCs) and inner hair cells(IHCs) in the mammalian co *** Ikzf2 is necessary for OHC development,the key gene re quired for IHC development remains *** found that deletion of Tbx2 in neonatal IHCs led to their transdifferentiation into OHCs by repressing 26.7% of IHC genes and inducing 56.3% of OHC genes,including *** importantly,persistent expression of Tbx2 coupled with transient Atohl expression effe ctively reprogrammed non-sensory supporting cells into new IHCs expressing the functional IHC marker *** differentiation status of these new IHCs was considerably more advanced than that previously ***,Tbx2 is essential for IHC development and co-upregulation of Tbx2 with Atohl in supporting cells represents a new approach for treating deafness related to IHC degeneration.

关键词： Tbx2 cochlea inner hair cell supporting cell Ikzf2 outer hair cell