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“Two Sessions”Chart a Clear Path in an Uncertain World

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China Today 2024年第4期73卷 21-23页

作者： WILLIAM JONES chongyang institute for financial studies under Renmin University of China

China is serving as an anchor of stability in a world engulfed in geopolitical rivalry and *** 2024 sessions of China’s top legislature and political advisory body exuded a strong sense of confidence in China’s ability to steer its course toward modernization in spite of the headwinds created by the hysterical reaction of some in the West over Beijing’s emergence as a world power.

关键词： spite winds World

G-forward performance process and representation of homothetic case via ergodic quadratic G-BSDE

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Probability, Uncertainty and Quantitative Risk 2024年第1期9卷 85-106页

作者： Yifan Sun Falei Wang Department of Applied Mathematics The Hong Kong Polytechnic UniversityKowloonHong KongChina Zhongtai Securities institute for financial studies and School of Mathematics Shandong UniversityJinan 250100China

We introduce a new type of robust forward criterion under model uncertainty,called the G-forward performance process,which extends the classical notion of forward performance process to the G-expectation *** then derive the representations of homothetic G-forward performance processes in a single stochastic factor model with uncertainty,building on the well-posedness of ergodic and infinite horizon backward stochastic differential equations driven by G-Brownian motion(G-BSDEs)with quadratic generators.

关键词： G-forward performance process Infinite horizon G-BSDE Ergodic G-BSDE

Cholesky GAS models for large time-varying covariance matrices

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Journal of Management Science and Engineering 2024年第1期9卷 115-142页

作者： Tingguo Zheng Shiqi Ye Department of Statistics and Data Science School of EconomicsXiamen UniversityXiamen361005China Wang Yanan institute for studies in Economics Xiamen UniversityXiamen361005China Paula and Gregory Chow institute for studies in Economics Xiamen UniversityXiamen361005China

This paper develops a new class of multivariate models for large-dimensional time-varying covariance matrices,called Cholesky generalized autoregressive score(GAS)models,which are based on the Cholesky decomposition of the covariance matrix and assume that the parameters are ***,two types of score-driven updates are considered:one is closer to the GARCH family,and the other is inspired by the stochastic volatility *** demonstrate that the models can be estimated equation-wise and are computationally feasible for high-dimensional ***,we design an equationwise dynamic model averaging or selection algorithm which simultaneously extracts model and parameter uncertainties,equipped with dynamically estimated model *** simulation results illustrate the superiority of the proposed ***,using a sizeable daily return dataset that includes 124 sectors in the Chinese stock market,two empirical studies with a small sample and a full sample are conducted to verify the advantages of our *** full sample analysis by a dynamic correlation network documents significant structural changes in the Chinese stock market before and after COVID-19.

关键词： Cholesky decomposition GAS Dynamic conditional correlations Dynamic model averaging

Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan Guo Gang Zhou Xiao Shen The institute for Advanced studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material *** this review,we summarize the investigations on the synthesis of organofluorine compounds with *** the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-*** the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine *** general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation

An advanced machine learning method for simultaneous breast cancer risk prediction and risk ranking in Chinese population: A prospective cohort and modeling study

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中华医学杂志(英文版) 2024年第17期137卷 2084-2091页

作者： Liu Liyuan He Yong Kao Chunyu Fan Yeye Yang Fu Wang Fei Yu Lixiang Zhou Fei Xiang Yujuan Huang Shuya Zheng Chao Cai Han Bao Heling Fang Liwen Wang Linhong Chen Zengjing Yu Zhigang Department of Breast Surgery The Second Hospital Cheeloo College of Medicine Shandong University Jinan Shandong China School of Mathematics Shandong University Jinan Shandong China Zhongtai Securities institute for financial studies Shandong University Jinan Shandong China institute of Translational Medicine of Breast Disease Prevention and Treatment Shandong University Jinan Shandong China Department of Maternal and Child Health School of Public Health Peking University Haidian District Beijing China National Center for Chronic and Non-communicable Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing China

Background: Breast cancer (BC) risk-stratification tools for Asian women that are highly accurate and can provide improved interpretation ability are lacking. We aimed to develop risk-stratification models to predict long- and short-term BC risk among Chinese women and to simultaneously rank potential non-experimental risk ***: The Breast Cancer Cohort Study in Chinese Women, a large ongoing prospective dynamic cohort study, includes 122,058 women aged 25-70 years old from the eastern part of China. We developed multiple machine-learning risk prediction models using parametric models (penalized logistic regression, bootstrap, and ensemble learning), which were the short-term ensemble penalized logistic regression (EPLR) risk prediction model and the ensemble penalized long-term (EPLT) risk prediction model to estimate BC risk. The models were assessed based on calibration and discrimination, and following this assessment, they were externally validated in new study participants from 2017 to ***: The AUC values of the short-term EPLR risk prediction model were 0.800 for the internal validation and 0.751 for the external validation set. For the long-term EPLT risk prediction model, the area under the receiver operating characteristic curve was 0.692 and 0.760 in internal and external validations, respectively. The net reclassification improvement index of the EPLT relative to the Gail and the Han Chinese Breast Cancer Prediction Model (HCBCP) models for external validation was 0.193 and 0.233, respectively, indicating that the EPLT model has higher classification ***: We developed the EPLR and EPLT models to screen populations with a high risk of developing BC. These can serve as useful tools to aid in risk-stratified screening and BC prevention.

关键词： Breast cancer Cancer prevention Models Women Risk assessment

Twistronics and moiréexcitonic physics in van der Waals heterostructures

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Frontiers of physics 2024年第4期19卷 147-185页

作者：李思维韦可刘祺瑞唐宇翔江天 College of Advanced Interdisciplinary studies National University of Defense TechnologyChangsha 410073China institute for Quantum Science and Technology National University of Defense TechnologyChangsha 410073China

Heterostructures composed of two-dimensional van der Waals(vdW)materials allow highly controllable stacking,where interlayer twist angles introduce a continuous degree of freedom to alter the electronic band structures and excitonic *** by the discovery of Mott insulating states and superconductivity in magic-angle bilayer graphene,the emerging research fields of“twistronics”and moiréphysics have aroused great academic interests in the engineering of optoelectronic properties and the exploration of new quantum phenomena,in which moirésuperlattice provides a pathway for the realization of artificial excitonic *** we systematically summarize the current achievements in twistronics and moiréexcitonic physics,with emphasis on the roles of lattice rotational mismatches and atomic ***,we review the effects of the interlayer twist on electronic and photonic physics,particularly on exciton properties such as dipole moment and spin-valley polarization,through interlayer interactions and electronic band *** also discuss the exciton dynamics in vdW heterostructures with different twist angles,like formation,transport and relaxation processes,whose mechanisms are complicated and still need further ***,we review the theoretical analysis and experimental observations of moirésuperlattice and moirémodulated *** exotic moiréeffects are also shown,including periodic potential,moiréminiband,and varying wave function symmetry,which result in exciton localization,emergent exciton peaks and spatially alternating optical selection *** further introduce the expanded properties of moirésystems with external modulation factors such as electric field,doping and strain,showing that moirélattice is a promising platform with high tunability for optoelectronic applications and in-depth study on frontier ***,we focus on the rapidly developing field of correlated electron physics based on the moiré

关键词： moirésuperlattice twistronics van der Waals heterostructure moiréexciton correlated electronic state

Whose Aid is Beneficial to Firms'Exports?Evidence from a Post-disaster Aid Experiment in China

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China & World Economy 2024年第2期32卷 73-96页

作者： Tan Li Qing Liu Lihe Xu School of International Business Southwestern University of Finance and EconomicsChina School of Economics Renmin University of ChinaChina institute of studies for the Greater Bay Area Guangdong University of Foreign StudiesChina

Post-disaster aid is widely regarded as important in helping local recovery and *** paper examines the effectiveness of post-disaster aid on exports,which are a driving factor of economic *** reports a natural experiment in China–the case of post-disaster aid following the Wenchuan earthquake in 2008–to examine how donors'experiences affected the exports of manufacturing firms in disaster-stricken *** export experience of the donor was *** coming from donors with more export experience was more beneficial to the exports of firms in recipient counties than aid from less experienced donors.“Learning from the donor”is a potential channel through which this effect *** is,firms in recipient counties learned from donors'export experience by exporting more products similar to those of donors,exporting more to the destination countries of donors,and participating in the donors'supply-chain networks by exporting more of the donors'***“learning from the donor”effects show that knowledge spillover can occur between spatially distant parties,which complements the literature.

关键词： China export knowledge spillover post-disaster aid

Toward a comprehensive hypothesis of oxygen-evolution reaction in the presence of iron and gold

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Journal of Energy Chemistry 2024年第2期89卷 172-183,I0005页

作者： Negah Hashemi Jafar Hussain Shah Cejun Hu Subhajit Nandy Pavlo Aleshkevych Sumbal Farid Keun Hwa Chae Wei Xie Taifeng Liu Junhu Wang Mohammad Mahdi Najafpour Department of Chemistry Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Center for Advanced Mössbauer Spectroscopy Mössbauer Effect Data CenterDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina Key Lab of Advanced Energy Materials Chemistry(Ministry of Education) Renewable Energy Conversion and Storage CenterCollege of ChemistryNankai UniversityTianjin 300071China Advanced Analysis Center Korea Institute of Science and TechnologySeoul 02792Republic of Korea institute of Physics Polish Academy of SciencesWarsaw 02-668Poland National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina Center of Climate Change and Global Warming Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran Research Center for Basic Sciences&Modern Technologies(RBST) Institute for Advanced Studies in Basic Sciences(IASBS)Zanjan 45137-66731Iran

This study investigates the effects of Fe on the oxygen-evolution reaction(OER)in the presence of *** distinct areas of OER were identified:the first associated with Fe sites at low overpotential(~330 mV),and the second with Au sites at high overpotential(~870 mV).Various factors such as surface Fe concentration,electrochemical method,scan rate,potential range,concentration,method of adding K_(2)Fe O_(4),nature of Fe,and temperature were varied to observe diverse behaviors during OER for Fe O_(x)H_(y)/*** amounts of Fe ions had a significant impact on OER,reaching a saturation point where the activity did not increase *** electronic interaction between Fe and Au ions was indicated by X-ray photoelectron spectroscopy(XPS)and electron paramagnetic resonance(EPR)*** situ visible spectroscopy confirmed the formation of Fe O_(4)^(2-)during *** situ Mossbauer and surfaceenhanced Raman spectroscopy(SERS)analyses suggest the involvement of Fe-based species as intermediates during the rate-determining step of OER.A lattice OER mechanism based on Fe O_(x)H_(y)was proposed for operation at low *** functional theory(DFT)calculations revealed that Fe oxide,Fe-oxide clusters,and Fe doping on the Au foil exhibited different activities and stabilities during *** study provides insights into the interplay between Fe and Au in OER,advancing the understanding of OER mechanisms and offering implications for the design of efficient electrocatalytic systems.

关键词： DFT calculation Fe/Au electrocatalysis Mechanism Oxygen evolution Water oxidation

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Impact of US financial Sanctions on the Dollar's International Status

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Contemporary International Relations 2024年第4期34卷 49-68页

作者： Ma Xue institute of American studies China Institutes of Contemporary International Relations

In 2022,the United States stepped up its sanctions on *** notably,it restricted the flow of the Russian Central Bank's foreign exchange(forex)assets,using financial administrative power as a source of strategic *** move should have reduced the appeal of US dollar assets but in reality has not accelerated as expected the decline of the greenback as a store of *** US dollar's share of global forex reserves increased instead of decreased during 2022 and *** the rise of economic costs caused by tightened US financial sanctions,countries that recognize the geopolitical role of the United States have further accepted the dollar's international status;their continued willingness to live with the dollar's“security premium”has given a fillip to the US dollar in the short term,boosting its appeal as a reserve ***,de-dollarization of forex reserves has yet to reach a sufficient scale,thus falling short of significantly challenging the dollar's *** a longer-term perspective,as economic and security conditions shift,countries that accept the dollar's international role or seek de-dollarization may change their *** a result,four possible scenarios may arise:(i)the preeminence of the US dollar remains unthreatened;(ii)the international monetary system splits into blocs;(iii)the international monetary system fragments;and(iv)the dollar loses its *** author believes that the last scenario is the most likely outcome.

关键词： de-dollarization international status of the US dollar national security US financial sanctions

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