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Research progress in assessment and strategies for sustainable food system within planetary boundaries

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Science China Earth Sciences 2024年第2期67卷 375-386页

作者： Minglei WANG Wenjiao shi Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China

Meeting the increasing food demand in a manner that ensures both resources and environmental sustainability poses a global challenge.The conceptual framework of planetary boundaries(PBs)has emerged as a crucial reference in the study of sustainable food system,with specific focuses on key dimensions such as land use change,freshwater use,nitrogen(N)and phosphorus(P)cycles,and greenhouse gas(GHG)emissions.In this study,we summarized the threshold applications of PBs in sustainable food system research at both the global and national(China)scales.Based on these thresholds,we evaluated the sustainability conditions of the food system,considering resources such as cropland,freshwater,N and P applications,as well as environmental impacts including N and P losses,and GHG emissions.In addition,we explored the impacts of single or combined management strategies on sustainable food systems.These strategies included dietary changes,improvements in technologies and management,reductions in food loss and waste,and optimization in agricultural production distribution.Finally,we outlined future research directions in sustainable food system,including enhancing research on the interaction mechanisms among PBs elements within food systems,conducting downscaling studies of PBs elements at national and regional levels,and ensuring the rationality of policy-making for sustainable food systems in China.This study can provide a theoretical foundation and strategies guidance for sustainable food system and agricultural land use management in the future both globally and in China.

关键词： Food system Resource use Environmental impacts Sustainable strategy Planetary boundaries

地方政府债务规模影响因素与区域差异研究——基于中国省级面板数据的分析

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云南财经大学学报 2022年第5期38卷 70-79页

作者：杨胜利黄世润西南民族大学经济学院成都610041

基于理论分析和典型事实,并利用2012—2018年中国30个省份的面板数据,实证分析地方政府债务规模的影响因素以及东、中、西部的区域差异。研究结果表明:在财政分权体制下,中国地方政府债务规模影响因素存在区域差异。其中,地方政府的竞... 详细信息

基于理论分析和典型事实,并利用2012—2018年中国30个省份的面板数据,实证分析地方政府债务规模的影响因素以及东、中、西部的区域差异。研究结果表明:在财政分权体制下,中国地方政府债务规模影响因素存在区域差异。其中,地方政府的竞争形式、所处的转移支付地位、应对财政压力的态度、土地财政水平、所处的社会经济环境等区域差异是影响地方政府债务规模存在区域差异的主要原因。在此基础上提出了制定差异化的地方政府债务风险管控政策、改革地方政府政绩考核制度、建立健全地方债务信息公开披露制度等政策建议。

关键词：地方政府债务转移支付区域差异

Lithospheric strength of the Anatolian plateau and implications for strong earthquake activity in Turkey

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Geodesy and Geodynamics 2024年第3期15卷 209-218页

作者： Yuhang Pan shi Chen Wen shi Institute of Geophysics China Earthquake AdministrationBeijing 100081China Beijing Baijiatuan Earth Science National Observation and Research Station Beijing 100095China

On February 6, 2023, the doublet earthquake including two main shocks with magnitudes M_(W)7.8 and M_(W)7.5, occurred near the western side of the East Anatolian Fault at the southeast boundary of the Anatolian Plateau in Turkey. Based on the WGM2012 Bouguer gravity anomaly data and the Etopo1topography data, this study first introduced a joint inversion of admittance and coherence functions and used the Bayesian optimal parameter estimation method to obtain the effective elastic thickness Teand loading ratio F of the lithosphere for various tectonic units in the Anatolian Plateau. Secondly, we discussed the characteristics and influencing factors of the lithospheric mechanical strength and analyzed its relationship with seismic activity. The lithospheric mechanical strength of the Anatolian Plateau showed clear lateral heterogeneity and a "weak-strong-weak" spatial pattern from east to west,reflecting various tectonic processes. At last, the strong seismic activity was found where the lithospheric strength was low in the Anatolian Plate. We also incorporated GPS strain rate and other results to investigate the tectonic background and primary causes of the M_(W)7.8 and M_(W)7.5 doublet earthquakes in Turkey. The results have a good insight into urban safety design in the Turkish region, including postdisaster rehabilitation, earthquake hazard assessment, and loss reduction.

关键词： Effective elastic thickness Anatolian plateau Turkey doublet earthquakes Bayesian optimization

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Induced pluripotent stem cells(iPSCs):molecular mechanisms of induction and applications

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Signal Transduction and Targeted Therapy 2024年第5期9卷 2065-2090页

作者： Jonas Cerneckis Hongxia Cai Yanhong shi Department of Neurodegenerative Diseases Beckman Research Institute of City of HopeDuarteCA 91010USA Irell&Manella Graduate School of Biological Sciences Beckman Research Institute of City of HopeDuarteCA 91010USA

The induced pluripotent stem cell(iPSC)technology has transformed in vitro research and holds great promise to advance regenerative medicine.iPSCs have the capacity for an almost unlimited expansion,are amenable to genetic engineering,and can be differentiated into most somatic cell types.iPSCs have been widely applied to model human development and diseases,perform drug screening,and develop cell therapies.In this review,we outline key developments in the iPSC field and highlight the immense versatility of the iPSC technology for in vitro modeling and therapeutic applications.We begin by discussing the pivotal discoveries that revealed the potential of a somatic cell nucleus for reprogramming and led to successful generation of iPSCs.We consider the molecular mechanisms and dynamics of somatic cell reprogramming as well as the numerous methods available to induce pluripotency.Subsequently,we discuss various iPSC-based cellular models,from mono-cultures of a single cell type to complex three-dimensional organoids,and how these models can be applied to elucidate the mechanisms of human development and diseases.We use examples of neurological disorders,coronavirus disease 2019(COVID-19),and cancer to highlight the diversity of disease-specific phenotypes that can be modeled using iPSC-derived cells.We also consider how iPSC-derived cellular models can be used in high-throughput drug screening and drug toxicity studies.Finally,we discuss the process of developing autologous and allogeneic iPSC-based cell therapies and their potential to alleviate human diseases.

关键词： mechanisms programming holds

Weakly Compact Sets and Riesz Representation Theorem in Musielak Sequence Spaces

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Acta Mathematica Sinica,English Series 2024年第2期40卷 467-484页

作者： Wan Zhong GONG Si Yu shi Zhong Rui shi Department of Mathematics Anhui Normal UniversityWuhu 241000P.R.China Smeal College of Business Pennsylvania State UniversityUniversity ParkPennsylwania 16802USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

In this work,we give some criteria of the weakly compact sets and a representation theorem of Riesz's type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak function.Finally,as an immediate consequence of the criteria considered in this paper,the criteria of the weakly compact sets of Orlicz sequence spaces are deduced.

关键词： Compact set weak topology Banach space dual space Musielak sequence spaces

UNIFORM SUPERCONVERGENCE ANALYSIS OF A TWO-GRID MIXED FINITE ELEMENT METHOD FOR THE TIME-DEPENDENT BI-WAVE PROBLEM MODELING D-WAVE SUPERCONDUCTORS

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Journal of Computational Mathematics 2024年第2期42卷 415-431页

作者： Yanmi Wu Dongyang shi PLA Information Engineering University Zhengzhou 450001China School of Mathematics and Information Sciences Yantai UniversityYantai 264005China

In this paper,a two-grid mixed finite element method(MFEM)of implicit Backward Euler(BE)formula is presented for the fourth order time-dependent singularly perturbed Bi-wave problem for d-wave superconductors by the nonconforming EQ_(1)^(rot) element.In this approach,the original nonlinear system is solved on the coarse mesh through the Newton iteration method,and then the linear system is computed on the fine mesh with Taylor’s expansion.Based on the high accuracy results of the chosen element,the uniform superclose and superconvergent estimates in the broken H^(1)-norm are derived,which are independent of the negative powers of the perturbation parameter appeared in the considered problem.Numerical results illustrate that the computing cost of the proposed two-grid method is much less than that of the conventional Galerkin MFEM without loss of accuracy.

关键词： Time-dependent Bi-wave problem Two-grid mixed finite element method Uniform superclose and superconvergent estimates

Suitable region of dynamic optimal interpolation for efficiently altimetry sea surface height mapping

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Geodesy and Geodynamics 2024年第2期15卷 142-149页

作者： Jiasheng shi Taoyong Jin School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China MOE Key Laboratory of Geospace Environment and Geodesy Wuhan UniversityWuhan 430079China

The dynamic optimal interpolation(DOI)method is a technique based on quasi-geostrophic dynamics for merging multi-satellite altimeter along-track observations to generate gridded absolute dynamic topography(ADT).Compared with the linear optimal interpolation(LOI)method,the DOI method can improve the accuracy of gridded ADT locally but with low computational efficiency.Consequently,considering both computational efficiency and accuracy,the DOI method is more suitable to be used only for regional applications.In this study,we propose to evaluate the suitable region for applying the DOI method based on the correlation between the absolute value of the Jacobian operator of the geostrophic stream function and the improvement achieved by the DOI method.After verifying the LOI and DOI methods,the suitable region was investigated in three typical areas:the Gulf Stream(25°N-50°N,55°W-80°W),the Japanese Kuroshio(25°N-45°N,135°E-155°E),and the South China Sea(5°N-25°N,100°E-125°E).We propose to use the DOI method only in regions outside the equatorial region and where the absolute value of the Jacobian operator of the geostrophic stream function is higher than1×10^(-11).

关键词： Dynamic optimal interpolation Linearoptimal interpolation Satellite altimetry Sea surface height Suitable region

Clinical features and prognostic factors of duodenal neuroendocrine tumours:A comparative study of ampullary and nonampullary regions

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 907-918页

作者： Sa Fang Yu-Peng shi Lu Wang Shuang Han Yong-Quan shi Department of Gastroenterology Honghui HospitalXi’an Jiaotong UniversityXi'an 710054Shanxi ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710032Shaanxi ProvinceChina Department of Gastroenterology Xijing Hospital Affiliated to Air Force Medical UniversityXi'an 710032Shaanxi ProvinceChina

BACKGROUND Duodenal neuroendocrine tumours(DNETs)are rare neoplasms.However,the incidence of DNETs has been increasing in recent years,especially as an incidental finding during endoscopic studies.Regrettably,there is no consensus regarding the ideal treatment of DNETs.Even there are few studies on the clinical features and survival analysis of DNETs.AIM To analyze the clinical characteristics and prognostic factors of patients with duodenal neuroendocrine tumours.METHODS The clinical data of DNETs diagnosed in the First Affiliated Hospital of Air Force Military Medical University from June 2011 to July 2022 were collected.Neuroen-docrine tumours located in the ampulla area of the duodenum were divided into the ampullary region group;neuroendocrine tumours in any part of the duo-denum outside the ampullary area were divided into the nonampullary region group.Using a retrospective study,the clinical characteristics of the two groups and risk factors affecting the survival of DNET patients were analysed.RESULTS Twenty-nine DNET patients were screened.The male to female ratio was 1:1.9,and females comprised the majority.The ampullary region group accounted for 24.1%(7/29),while the nonampullary region group accounted for 75.9%(22/29).When diagnosed,the clinical symptoms of the ampullary region group were mainly abdominal pain(85.7%),while those of the nonampullary region groups were mainly abdominal distension(59.1%).There were differences in the composition of staging of tumours between the two groups(Fisher's exact probability method,P=0.001),with nonampullary stage II tumours(68.2%)being the main stage(P<0.05).After the diagnosis of DNETs,the survival rate of the ampullary region group was 14.3%(1/7),which was lower than that of 72.7%(16/22)in the nonampullary region group(Fisher's exact probability method,P=0.011).The survival time of the ampullary region group was shorter than that of the nonampullary region group(P<0.000).The median survival time of the ampullary region group was 10.0 months and that of the no

关键词： Duodenum Neuroendocrine Tumour Ampullary Nonampullary Clinical features Prognostic

Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

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Petroleum Science 2024年第1期21卷 343-351页

作者： Yang Wang Jia Zhang shi-Long Yang Ze-Xuan Xu shi-Qing Cheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil recovery.In contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective permeability.Meanwhile,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant breakage.In this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer flooding.The hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer solution.The combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir pressure.Compared with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore section.The field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and the far-wellbore section with low fracture conduct

关键词： Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis