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Journal of Systems Science & Complexity 2024年第3期37卷 1052-1079页

作者： BAI Wei zhang junting LIU Haifei LIU Kai School of Management and Engineering Nanjing UniversityNanjing 210093China Postdoctoral Workstation of Bank of Jiangsu Co. LtdNanjing 210006China College of Finance Nanjing Agricultural UniversityNanjing 210095China University of Prince Edward Island 550 University AveCharlottetownPE C1A4P3Canada

In order to build a low-risk Fund of Funds(FOF), from the perspective of correlation, the principal component factor is used to improve the traditional risk parity model. Principal component analysis is used to decompose the underlying assets and generate unrelated principal component factors,and then the authors can construct a principal component risk parity portfolio. The proposed empirical results based on China’s mutual fund market show that the performance of principal component risk parity portfolio(PCRPP) is better than that of equal weight portfolio(EWP) and traditional risk parity portfolio(RPP). That is to say, not only the PCRPP in this paper has much lower risk than EWP and RPP, but also slightly better than EWP and RPP in terms of average return. Moreover, the study of dividing the underlying assets shows that the PCRPP in this paper is not sensitive to the underlying assets. The PCRPP in this paper is better than EWP and RPP for both the better performing funds and the worse performing funds. In addition, the empirical results on dynamic portfolio adjustments show that it is not appropriate to adjust asset allocation too frequently when the expected rate of return is calculated using the arithmetic mean.

关键词： Fund of funds(FOF) mutual funds portfolio risk principal component analysis risk parity portfolio

Construction and Application of a Regional Kilometer-Scale Carbon Source and Sink Assimilation Inversion System(CCMVS-R)

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Engineering 2024年第2期33卷 263-275页

作者： Lifeng Guo Xiaoye zhang junting Zhong Deying Wang Changhong Miao Licheng Zhao Zijiang Zhou Jie Liao Bo Hu Lingyun Zhu Yan Chen Monitoring and Assessment Center for GHGs and Carbon Neutrality&Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China Laboratory of Climate Change Mitigation and Carbon Neutrality Henan UniversityZhengzhou 450001China National Meteorological Information Center Beijing 100081China Shanxi Meteorological Administration Taiyuan 030002China Shanxi Provincial Institute of Meteorological Sciences Taiyuan 030002China Jiangsu Provincial Climate Center Nanjing 210000China

CO_(2)is one of the most important greenhouse gases(GHGs)in the earth’s atmosphere.Since the industrial era,anthropogenic activities have emitted excessive quantities of GHGs into the atmosphere,resulting in climate warming since the 1950s and leading to an increased frequency of extreme weather and climate events.In 2020,China committed to striving for carbon neutrality by 2060.This commitment and China’s consequent actions will result in significant changes in global and regional anthropogenic carbon emissions and therefore require timely,comprehensive,and objective monitoring and verification support(MVS)systems.The MVS approach relies on the top-down assimilation and inversion of atmospheric CO_(2)concentrations,as recommended by the Intergovernmental Panel on Climate Change(IPCC)Inventory Guidelines in 2019.However,the regional high-resolution assimilation and inversion method is still in its initial stage of development.Here,we have constructed an inverse system for carbon sources and sinks at the kilometer level by coupling proper orthogonal decomposition(POD)with four-dimensional variational(4DVar)data assimilation based on the weather research and forecasting-greenhouse gas(WRF-GHG)model.Our China Carbon Monito ring and Verification Support at the Regional level(CCMVS-R)system can continuously assimilate information on atmospheric CO_(2)and other related information and realize the inversion of regional and local anthropogenic carbon emissions and natural terrestrial ecosystem carbon exchange.Atmospheric CO_(2)data were collected from six ground-based monito ring sites in Shanxi Province,China to verify the inversion effect of regio nal anthropogenic carbon emissions by setting ideal and real experiments using a two-layer nesting method(at 27 and 9 km).The uncertainty of the simulated atmospheric CO_(2)decreased significantly,with a root-mean-square error of CO_(2)concentration values between the ideal value and the simulated after assimilation was close to 0.The total anthropogenic carbon emissions in S

关键词： CCMVS-R Regional carbon assimilation system Anthropogenic carbon emissions CO_(2) POD 4DVar

Recent advances in the electrocatalytic oxidative upgrading of lignocellulosic biomass

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ChemPhysMater

ChemPhysMater 2024年第2期3卷 157-186页

作者： Yufeng Qi Hairui Guo junting Li Li Ma Yang Xu Huiling Liu Cheng Wanga Zhicheng zhang Institute for New Energy Materials and Low-Carbon Technologies School of Materials Science and EngineeringTianjin Key Laboratory of Advanced Functional Porous MaterialsTianjinUniversityof TechnologyTianjin 300384China Key Laboratory of Organic Integrated Circuit Minitry of Education&Tianjin Key Laboratoryof Molecular Optoelectronic Sciencespartment of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

Lignocellulosic biomass is a critical renewable carbon resource,but most of its utilization is inefficient,and elec-trocatalytic oxidation is a promising method of upgrading lignocellulose into value-added fuels and chemicals under mild operating conditions.Recently,efforts to enable conversion with a high efficiency and low energy con-sumption have been reported,but understanding the reaction mechanisms and realizing scaled-up applications of the electrooxidation of lignocellulosic biomass are still in their early stages.A timely overview of recently reported general reaction mechanisms,particularly the strategies developed for use in improving the reaction efficiencies,is necessary to inspire research regarding the highly efficient utilization of lignocellulose.Herein,we summa-rize the strategies developed to improve electrocatalytic performance in oxidative lignocellulose conversion.The organized summary includes strategies ranging from designing efficient electrocatalysts and adding functional co-catalysts or electrolytes to employing advanced electrolyzers.A comprehensive overview of representative examples should provide universal principles to yield insight into the reaction processes and guide the design of efficient electrocatalytic systems.Finally,the challenges and opportunities in developing the electrocatalytic oxidative upgrading of lignocellulosic biomass in the near future are proposed.

关键词： Biomass conversion Lignocellulose Electrocatalysis Oxidative upgrading Electrocatalyst

Spatiotemporal distribution, environmental risk and carbon emission reduction potential of livestock manure in Shaanxi Province, China

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Frontiers of Agricultural Science and Engineering 2024年第3期11卷 381-396页

作者： Mengyuan QIAO Jianchun ZHU Ronghua LI junting PAN Ran XIAO Hailong WANG Kuok Ho Daniel TANG Zengqiang zhang College of Humanities & Social Development Northwest A&F University College of Natural Resources and Environment Northwest A&F University Key Laboratory of Low-carbon Green Agriculture in Northwestern China Ministry of Agriculture and Rural Affairs Key Laboratory of Non-point Source Pollution of Ministry of Agricultural and Rural Affairs Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and Environment Southwest University Biochar Engineering Technology Research Center of Guangdong Province School of Environmental and Chemical Engineering Foshan University Department of Environmental Science University of Arizona

Shaanxi is a leading province in animal husbandry（AH） in China. However, the lack of provincial information on the characteristics and utilization potential of livestock manure（LM） hinders crucial management decisions. Therefore, we investigated the spatiotemporal distribution, availability and biogas potential of LM in Shaanxi, and examine the carbon emission reduction potential of AH.There has been a 1.26-fold increase in LM quantities in Shaanxi over the past 35 years, reaching 4635.6 × 10～4 t by 2021. LM was mainly concentrated in northern Shaanxi and the eastern part of Hanzhong. Cattle and pig manure were the primary sources of LM, with the average LM land-load of 14.57 t·ha-1in 2021. While the overall AH in Shaanxi has not exceeded the environmental capacity, the actual scales of AH in Ankang and Hanzhong have already surpassed the respective environmental capacities, posing a higher risk of N and P pollutions. In 2021, the estimated biogas energy potential of LM was 1.2 × 1011MJ. From 2012 to 2021, the average carbon emission reduction potential in Shaanxi was 22%, with an average potential scale of 10%. The results of this research provide valuable data and policy recommendations for promoting the intensive use of LM and reducing carbon emissions in Shaanxi.

关键词： Livestock manure emission estimation N and P loads biogas potential carbon emission reduction

ADAR1 regulates vascular remodeling in hypoxic pulmonary hypertension through N1-methyladenosine modification of circCDK17

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Acta Pharmaceutica Sinica B 2023年第12期13卷 4840-4855页

作者： junting zhang Yiying Li Jianchao zhang Lu Liu Yuan Chen Xusheng Yang Xueyi Liao Muhua He Zihui Jia Jun Fan Jin-Song Bian Xiaowei Nie Shenzhen Institute of Respiratory Disease Shenzhen Key Laboratory of Respiratory DiseaseShenzhen People's Hospital(the Second Clinical Medical CollegeJinan Universitythe First Afiliated HospitalSouthern University of Science and Technology)Shenzhen 518020China Post-Doctoral Scientific Research Station of Basic Medicine JinanUniversityGuangzhou 510632China Department of Pharmacology School of MedicineSouthern University of Science and TechnologyShenzhen 518055China Lung Transplant Group Wuxi People's Hospital Affliated to Nanjing Medical UniversityWuxi 211103China Department of Medical Biochemistry and Molecular Biology School of MedicineJinan UniversityGuangzhou 510632China

Pulmonary hypertension(PH)is an extremely malignant pulmonary vascular disease of unknown etiology.ADAR1 is an RNA editing enzyme that converts adenosine in RNA to inosine,thereby affecting RNA expression.However,the role of ADAR1 in PH development remains unclear.In the present study,we investigated the biological role and molecular mechanism of ADAR1 in PH pulmonary vascular remodeling.Overexpression of ADAR1 aggravated PH progression and promoted the proliferation of pulmonary artery smooth muscle cells(PASMCs).Conversely,inhibition of ADAR1 produced opposite effects.High-throughput whole transcriptome sequencing showed that ADAR1 was an important regulator of circRNAs in PH.CircCDK17 level was significantly lowered in the serum of PH patients.The effects of ADAR1 on cell cycle progression and proliferation were mediated by circCDK17.ADAR1 affects the stability of circCDK17 by mediating A-to-I modification at the A5 and A293 sites of circCDK17 to prevent it from mlA modification.We demonstrate for the first time that ADAR1 contributes to the PH development,at least partially,through m1A modification of circCDK17 and the subsequent PASMCs proliferation.Our study provides a novel therapeutic strategy for treatment of PH and the evidence for circCDK17 as a potential novel marker for the diagnosis of this disease.

关键词： Pulmonary hypertension ADAR1 Circular RNA Vascular remodeling Cell proliferation

Scalable and general synthesis of spinel manganese- based cathodes with hierarchical yolk-shell structure and superior lithium storage properties

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Nano Research 2018年第1期11卷 246-253页

作者： Yu Wu junting zhang Chuanbao Cao Research Center of Materials Science Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and GreenApplications Beijing Institute of Technology Beijing 10008 I China

Hierarchical yolk-shell structured cathodes with controllable composition are potentially attractive materials for the fabrication of lithium-ion batteries, but they are difficult to synthesize. In this work, we present a simple, scalable, and general morphology-inheritance strategy to synthesize spinel manganese cathodes with a hierarchical yolk-shell structure. Starting from uniform Mn carbonate spheres prepared by an ultrafast and scalable microwave-assisted method, we show that the subsequent sintering results in the formation of Mn203 precursors with a yolk-shell structure, which can be effectively transferred to spinel manganese cathodes via simple impregnation and solid-state reaction. Owing to the simple and scalable nature of the present strategy, materials prepared through this approach have great potential as cathodes of lithium-ion batteries, where they can lead to high specific capacity, outstanding cyclability, and superior rate capability. In particular, both LiMn204 and LiNi05Mn1504 with hierarchical yolk-shell structure achieved nearly theoretical capacity, without any apparent decay after 100 cycles at I C. Moreover, 80% of the initial discharge capacities of both samples can be maintained for up to 500 cycles at a high rate of 10 C.

关键词： yolk-shell structures,microwave-assistedmethod,scalable synthesis,spinel manganese cathodes,lithium-ion batteries

An Effective Thin Reservoir Identification Method for Fine Oilfield Development

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Engineering（科研） 2023年第5期15卷 342-351页

作者： Zheng Lv Xin Wang Chunyuan Shi junting zhang Bohai Oilfield Research Institute of CNOOC Ltd.-Tianjin Branch Tianjin China

Thin reservoirs prediction method such as spectral inversion has drawn considerable attention in recent years. In order to avoid extracting wavelets within the whole field area purposeless and to make the filtered data has preferable fidelity as well as signal-to-noise ratio, an effective structural constrained thin reservoir description method which combines spectral inversion and wide-band Ricker wavelet filtering technology has been proposed in this paper. The method given here is more credible and is suitable for the prediction of middle-deep thin reservoirs. We take LD-A structure within Bohai Bay Basin as an example to show the implement of our method. Several sets of thin sand layers which are hardly to recognize originally have been finally identified. Also, with the application of this method, a high-production thin reservoir of LD-B structure has been identified accurately, which provides credible information for subsequent fine oil exploration and development.

关键词： Structure Constrained Thin Reservoir Spectral Inversion Wide-Band Ricker Wavelet Exploration and Development

Research on Optimization Design of Deep Profile Control Injection Scheme in Block S

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Open Journal of Applied Sciences 2023年第11期13卷 2047-2054页

作者： Meinan Wang Shaopeng Wang Wei zhang Xiaoqi Chen junting zhang Bohai Oilfield Research Institute of CNOOC Ltd.-Tianjin Branch Tianjin China

In view of the rapid decline rate of oil production and gradual increase of water cut in oil wells in Block S, based on the determination of the formula of foam profile control agent, the optimization study of foam profile control injection scheme was carried out. Petrel software is used to establish a facies controlled geological model based on stochastic modeling method in Block S, and CMG software is used for numerical simulation to design 7 sets of foam profile control prediction schemes. Dynamic data and numerical simulation methods are used to optimize foam injection mode and injection cycle. By simulating and calculating, the optimal injection method of alternating gas and liquid injection and the optimal plan with an injection period of 2 months were selected. Through the calculation results of various research plans, it can be seen that the water content of the optimal plan has decreased significantly, and the oil production rate has increased significantly, in order to slow down production decline, control water content rise, extend the economic recovery period of the oilfield, and achieve the goal of improving oil recovery.

关键词： Foam Profile Control Numerical Simulation Injection Method Injection Cycle

基于中子活化瞬发伽马能谱确定地层元素含量的方法

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中国无机分析化学 2024年第6期14卷 786-794页

作者：张锋王含范珺亭张慧中国石油大学(华东)地球科学与技术学院山东青岛266580

中子技术能够利用中子与物质的相互作用确定其组成等性质,广泛应用于医学、环境科学、核反应堆建设、金属矿产勘查及石油工业中。在石油天然气领域,中子探测技术主要被用于确定井孔中的孔隙度、密度和流体饱和度等参数。随着测井技术的... 详细信息

中子技术能够利用中子与物质的相互作用确定其组成等性质,广泛应用于医学、环境科学、核反应堆建设、金属矿产勘查及石油工业中。在石油天然气领域,中子探测技术主要被用于确定井孔中的孔隙度、密度和流体饱和度等参数。随着测井技术的不断发展,基于瞬发伽马射线的中子活化分析技术也已应用于井下确定地层元素含量,并成为复杂岩性和非常规油气储层获得矿物含量的唯一手段。通过归纳地层元素伽马能谱测井的方法,利用蒙特卡罗方法模拟不同地层条件下的伽马能谱,构建地层元素的标准谱库,研究奇异值分解和极大似然估计能谱数据处理方法,并利用得到的元素产额及氧闭合模型实现地层元素含量的确定。利用蒙特卡罗方法构建已知地层的伽马能谱,采用上述数据处理方法得到元素含量与地层真实元素含量误差均在4%之内,Si误差最大为2.8%,Ca最大误差为3.3%,研究结果为井下确定地层元素成分及含量提供了有效的技术支持。

关键词：中子技术应用地层元素测井能谱数据处理蒙特卡罗模拟

Somatic GJA4 mutation in intracranial extra-axial cavernous hemangiomas

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Stroke & Vascular Neurology 2023年第6期8卷 453-462,I0003-I0037页

作者： Ran Huo Yingxi Yang Hongyuan Xu Shaozhi Zhao Dong Song Jiancong Weng Ruochen Ma Yingfan Sun Jie Wang Yuming Jiao Junze zhang Qiheng He Ruolei Wu Shuo Wang Ji-Zong Zhao junting zhang Jiguang Wang Yong Cao Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijingChina China National Clinical Research Center for Neurological Diseases BeijingChina Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina Division of Life Science Center for Systems Biology and Human Health and State Key Laboratory of Molecular NeuroscienceThe Hong Kong University of Science and TechnologyHong KongChina Department of Neurosurgery China-Japan Friendship HospitalBeijingChina School of Medical Technology Beijing Institute of TechnologyBeijingChina Hong Kong Center for Neurodegenerative Diseases InnoHKHong Kong SARChina Beijing Neurosurgical Institute Capital Medical UniversityBeijingChina

Objective Extra-axial cavernous hemangiomas(ECHs)are sporadic and rare intracranial occupational lesions that usually occur within the cavernous sinus.The aetiology of ECHs remains unknown.Methods Whole-exome sequencing was performed on ECH lesions from 12 patients(discovery cohort)and droplet digital polymerase-chain reaction(ddPCR)was used to confirm the identified mutation in 46 additional cases(validation cohort).Laser capture microdissection(LCM)was carried out to capture and characterise subgroups of tissue cells.Mechanistic and functional investigations were carried out in human umbilical vein endothelial cells and a newly established mouse model.Results We detected somatic GJA4 mutation(c.121G>T,p.G41C)in 5/12 patients with ECH in the discovery cohort and confirmed the finding in the validation cohort(16/46).LCM followed by ddPCR revealed that the mutation was enriched in lesional endothelium.In vitro experiments in endothelial cells demonstrated that the GJA4 mutation activated SGK-1 signalling that in turn upregulated key genes involved in cell hyperproliferation and the loss of arterial specification.Compared with wild-type littermates,mice overexpressing the GJA4 mutation developed ECH-like pathological morphological characteristics(dilated venous lumen and elevated vascular density)in the retinal superficial vascular plexus at the postnatal 3 weeks,which were reversed by an SGK1 inhibitor,EMD638683.Conclusions We identified a somatic GJA4 mutation that presents in over one-third of ECH lesions and proposed that ECHs are vascular malformations due to GJA4-induced activation of the SGK1 signalling pathway in brain endothelial cells.

关键词： intracranial superficial hemangioma