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Cachazo-Svr?ek-Witten rules for tree-level gluonic amplitudes revisited

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Science China(Physics,Mechanics & Astronomy) 2022年第4期65卷 24-35页

作者： Wen-Jie Zhang jun-bao wu Chuan-Jie Zhu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin University Peng Huanwu Center for Fundamental Theory College of Mathematics and Physics Science Hunan University of Arts and Science

We provide a new proof of Cachazo-Svrˇcek-Witten rules for tree-level gluonic amplitudes. As a key step, we explicitly demonstrate the cancellation of spurious poles originating from the maximally helicity violating vertices in these rules. To achieve this,we introduce specially-defined two-off-shell-line sub-amplitudes and examine their residues at spurious poles.

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Hawking radiation of Dirac particles from soft-hairy black holes

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Communications in Theoretical Physics 2022年第4期74卷 68-71页

作者： Wen-Jie Zhang Pu-Jian Mao jun-bao wu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin University University135 Yaguan RoadTianjin 300350China

In this paper,we study the Hawking radiation of Dirac particles via tunneling formalism from linearly supertranslated Schwarzschild black holes.We find that the radiation spectrum and the Hawking temperature remain th... 详细信息

关键词： quantum aspects of black holes quantum field theory in curved spacetime black hole thermodynamics

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How incubation temperature affects hatchling performance in reptiles: an integrative insight based on plasticity in metabolic enzyme

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Current Zoology 2024年第2期70卷 195-203页

作者： Dan-Yang wu Xing-Zhi Han Teng Li bao-jun Sun Xiao-Yan Qin College of Life and Environment Sciences Minzu University of ChinaBeijing 100081China Key Laboratory of Animal Ecology and Conservational Biology Institute of ZoologyChinese Academy of SciencesBeijing 10011China College of Wildlife and Protected Area Northeast Forestry UniversityHarbin 150040China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China

Evaluating the effects of temperature variations on animals plays an important role in understanding the threat of climate warming.The effects of developmental temperature on offspring performance are critical in evaluating the effects of warming temperatures on the fitness of ovipa-rous species,but the physiological and biochemical basis of this developmental plasticity is largely unknown.In this study,we incubated eggs of the turtle Pelodiscus sinensis at low(24℃),medium(28℃),and high(32℃)temperatures,and evaluated the effects of developmental temperature on offspring fitness,and metabolic enzymes in the neck and limb muscles of hatchlings.The hatchlings from eggs incubated at the medium temperature showed better fitness-related performance(righting response and swimming capacity)and higher activities of metabolic enzymes(hexokinase,HK;lactate dehydrogenase,LDH)than hatchlings from the eggs incubated at high or low temperatures.In addition,the swimming speed and righting response were significantly correlated with the HK activities in limb(swimming speed)and neck(righting response)muscles,suggesting that the developmental plasticity of energy metabolic pathway might play a role in determining the way incubation temperature affects offspring phenotypes.Integrating the fitness-related performance and the activities of metabolic enzymes,we predict that the P sinensis from high latitude would not face the detrimental effects of climate warming until the average nest temperatures reach 32℃.

关键词： developmental plasticity energetic metabolism enzyme activity hatchling turtle.

Sequential enantioselective Ugi-4CR/post-Ugi transformation strategy:a precise construction of structurally diverse azaspiro polycyclic scaffolds

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Science China Chemistry 2024年第2期67卷 576-586页

作者： Xiao-bao wu jun-Xiu Shi Yi-Ming Ou Hua-Jie Jiang Yi-jun Fang Qi-Ming Wang Quan Gao Jie Yu Department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic scaffolds.Structurally diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

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Multi-level coarse-grained discrete element method modeling of cylinder particle flow in a rotating drum

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Particuology 2024年第5期88卷 218-238页

作者： Lei Xu Xiukai wu Shuai Wang Shiyi bao Institute of Process Equipment and Control Engineering Zhejiang University of TechnologyHangzhou 310023China Engineering Research Center of Process Equipment and Remanufacturing Ministry of EducationZhejiang University of TechnologyHangzhou 310023China College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

The coarse-grained discrete element method(DEM)is probably a feasible option for simulating an actual drum-type biomass boiler,which contains over 10 million cylinder particles.A multi-level study was conducted based on particle and coarse-grained level data to evaluate the adequacy of the coarse-grained approach in terms of geometrical characteristics,kinematic features,and dynamic properties.Two scaling laws for contact parameters were used and compared during the simulations.The results show that the coarse-grained approach can accurately predict the positions of the free surface and active-passive interface,the mixing index,and the orientation properties.Deviations in the velocity fields may occur due to the worse flowability of coarse-grained particles near the free surface.The efficiency is significantly improved by the coarse-grained model compared with the corresponding original case(the same DEM code without a coarse-grained model was used for the original simulations).

关键词： Coarse-grained method Discrete element method(DEM) Cylinder particle Rotating drum Granular flow

Insights into postural orthostatic tachycardia syndrome after COVID-19 in pediatric patients

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World Journal of Pediatrics 2024年第3期20卷 201-207页

作者： Ya-Xi Cui jun-bao Du Hong-Fang Jin Department of Pediatrics Peking University First HospitalNo.1 Xi-an Men StreetWest DistrictBeijing 100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijing 100191China

The pandemic caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)profoundly threatened human health globally and greatly impacted the world economy[1].While most patients recovered,some suff... 详细信息

关键词： acute patients tachycardia

Inflection Point Age in the Middle and Older Women—Jiangxi Province,China,2020-2022

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China CDC weekly 2024年第9期6卷 162-167页

作者： Shanlan Yang Langlang Zhang Helang Huang Jiaofeng Wang Lei wu Zhijun bao Shanghai Institute of Infectious Disease and Biosecurity Fudan UniversityShanghaiChina Department of Gerontology Huadong Hospital Affiliated to Fudan UniversityShanghai Key Laboratory of Clinical Geriatric MedicineResearch Center on Aging and MedicineFudan UniversityShanghaiChina Jiangxi Provincial Key Laboratory of Preventive Medicine School of Public HealthNanchang UniversityNanchang CityJiangxi ProvinceChina

Summary What is already known about this topic?Previous studies have predominantly examined the micro-level aspects of women aging inflection points,while macro-level research using big data on the inflection points o... 详细信息

关键词： Middle Jiangxi currently

Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

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General Psychiatry 2024年第2期37卷 177-188页

作者： Meng-Di Yuan jun-Fa Liu bao-Liang Zhong Research Center for Psychological and Health Sciences China University of Geosciences(Wuhan)WuhanHubeiChina Department of Psychiatry Wuhan Mental Health CentreWuhanHubeiChina

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553.

关键词： symptoms prevalence analysis

Unlocking the potential of thin-film composite reverse osmosis membrane performance:Insights from mass transfer modeling

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Chinese Chemical Letters 2024年第5期35卷 66-76页

作者： Kexin Yuan Yulei Liu Haoran Feng Yi Liu jun Cheng Beiyang Luo Qinglian wu Xinyu Zhang Ying Wang Xian bao Wanqian Guo jun Ma State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China College of Architecture and Environment Sichuan UniversityChengdu 610065China School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJi’nan 250101China College of Water Conservancy and Hydropower Engineering Sichuan Agricultural UniversityYaan 625014China

Thin-film composite(TFC)reverse osmosis(RO)membranes have attracted considerable attention in water treatment and desalination processes due to their specific separation advantages.Nevertheless,the trade-off effect between water flux and salt rejection poses huge challenges to further improvement in TFC RO membrane performance.Numerous research works have been dedicated to optimizing membrane fabrication and modification for addressing this issue.In the meantime,several reviews summarized these approaches.However,the existing reviews seldom analyzed these methods from a theoretical perspective and thus failed to offer effective optimization directions for the RO process from the root cause.In this review,we first propose a mass transfer model to facilitate a better understanding of the entire process of how water and solute permeate through RO membranes in detail,namely the migration process outside the membrane,the dissolution process on the membrane surface,and the diffusion process within the membrane.Thereafter,the water and salt mass transfer behaviors obtained from model deduction are comprehensively analyzed to provide potential guidelines for alleviating the trade-off effect between water flux and salt rejection in the RO process.Finally,inspired by the theoretical analysis and the accurate identification of existing bottlenecks,several promising strategies for both regulating RO membranes and optimizing operational conditions are proposed to further exploit the potential of RO membrane performance.This review is expected to guide the development of high-performance RO membranes from a mass transfer theory standpoint.

关键词： Reverse osmosis Mass transfer model Trade-off effect Membrane performance Optimization strategies

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