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Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution

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Petroleum Science 2024年第3期21卷 1765-1779页

作者： yan-zhong Liang Bai-Lu Teng Wan-Jing Luo School of Energy Resources China University of Geosciences(Beijing)Beijing100083China

During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional ***,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field ***,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux ***,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow *** using the finite difference method,we can obtain the numerical solutions of the transient flow within the *** the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the *** complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient ***,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional *** computation results show that the flux variation along the direction well has a significant effect on pressure *** addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial *** horizontal linear flow can be observed only if the formation thickness is much smaller than the well ***,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore.

关键词： Directional well Pressure transient behavior Semi-analytical model Non-uniform flux

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Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics

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Journal of Integrative Agriculture 2024年第3期23卷 876-887页

作者： Liyao Su Min Wu Tian Zhang yan zhong Zongming(Max) Cheng State Key Laboratory of Crop Genetics and Germplasm Enhancement College of HorticultureNanjing Agricultural UniversityNanjing210095China

Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii.

关键词： Rosa roxburghii quercetin derivatives weighted gene co-expression network analysis transcription factor transcriptome metabolome

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Quantum block coherence with respect to projective measurements

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Chinese Physics B 2024年第8期33卷 213-220页

作者：王璞李忠艳孟会贤 School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China School of Mathematics and Physics North China Electric Power UniversityBeijing 102206China

Quantum coherence serves as a defining characteristic of quantum mechanics,finding extensive applications in quantum computing and quantum communication *** study explores quantum block coherence in the context of projective measurements,focusing on the quantification of such ***,we define the correlation function between the two general projective measurements P and Q,and analyze the connection between sets of block incoherent states related to two compatible projective measurements P and ***,we discuss the measure of quantum block coherence with respect to projective *** on a given measure of quantum block coherence,we characterize the existence of maximal block coherent states through projective *** research integrates the compatibility of projective measurements with the framework of quantum block coherence,contributing to the advancement of block coherence measurement theory.

关键词： quantum coherence compatibility projective measurement quantum block coherence

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Positron Emission Tomography Imaging of Synaptic Dysfunction in Parkinson’s Disease

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Neuroscience Bulletin 2024年第6期40卷 743-758页

作者： Jiaqi Niu yan zhong Chentao Jin Peili Cen Jing Wang Chunyi Cui Le Xue Xingyue Cui Mei Tian Hong Zhang Department of Nuclear Medicine and PET Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou310009China Institute of Nuclear Medicine and Molecular Imaging Zhejiang UniversityHangzhou310009China Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou310009China College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou310014China Key Laboratory for Biomedical Engineering of Ministry of Education Zhejiang UniversityHangzhou310014China Huashan Hospital and Human Phenome Institute Fudan UniversityShanghai200040China

Parkinson’s disease(PD)is one of the most common neurodegenerative diseases with a complex *** formed by abnormal deposition of alpha-synuclein(αSyn)lead to synapse dysfunction of the dopamine and non-dopamine *** loss of dopaminergic neurons and concomitant alterations in non-dopaminergic function in PD constitute its primary pathological *** emission tomography(PET),as a representative molecular imaging technique,enables the non-invasive visualization,characterization,and quantification of biological processes at cellular and molecular *** synaptic function with PET would provide insights into the mechanisms underlying PD and facilitate the optimization of clinical *** this review,we focus on the synaptic dysfunction associated with theαSyn pathology of PD,summarize various related targets and radiopharmaceuticals,and discuss applications and perspectives of PET imaging of synaptic dysfunction in PD.

关键词： Parkinson’s disease Positron emission tomography Synapse dysfunction Alpha-synuclein Dopamine system Non-dopamine system

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Delayed neurological dysfunction following posterior laminectomy with lateral mass screw fixation:A case report and review of literature

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World Journal of Clinical Cases 2024年第7期12卷 1356-1364页

作者： Rui-zhong yan Chao Chen Chu-Ran Lin yan-Hui Wei Zhi-Jian Guo Ya-Kun Li Quan Zhang He-Yi Shen Hao-Lin Sun Department of Orthopedics Taiyuan Central HospitalTaiyuan 030009Shanxi ProvinceChina Department of Orthopedics Graduate School Shanxi University of Traditional Chinese MedicineTaiyuan 030024Shanxi ProvinceChina Department of Orthopedics Peking University First HospitalBeijing 100034China

BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity and *** neurological dysfunction is diagnosed in cases when symptoms present>3 d *** to its rarity,the risk factors for delayed neurological dysfunction are ***,this condition can result in irreversible neurological deficits and serious *** this paper,we present a case of postoperative SEH that developed three days after hematoma *** SUMMARY A 68-year-old man with an American Spinal Injury Association(ASIA)grade C injury was admitted to our hospital with neck pain and tetraplegia following a *** C3-C7 posterior laminectomy and the lateral mass screw fixation surgery were performed on the tenth ***,the patient showed no changes in muscle strength or ASIA *** patient experienced neck pain and subcutaneous swelling on the third day postoperatively,his muscle strength decreased,and his ASIA score was grade *** resonance imaging showed hypointense signals on T1 weighted image(T1WI)and T2WI located behind the epidural space,with spinal cord *** surgical intervention for the hematoma was performed 12 h after *** hypoproteinemia and pleural effusion did not improve in the perioperative period,the patient recovered to ASIA grade C on day 30 after surgery,and was transferred to a functional rehabilitation exercise *** This case shows that amelioration of low blood albumin and pleural effusion is an important aspect of the perioperative management of cervical *** to relieve the pressure on the spinal cord should be performed as soon as possible to decrease neurological disabilities.

关键词： Delayed postoperative spinal epidural hematoma Complications Spinal surgery Hypoproteinemia Risk factor Case report

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Chiral transfer amidst one-dimensional linear polymers and twodimensional network covalent organic frameworks:Striking a fine balance between helicity and crystallinity

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Nano Research 2024年第6期17卷 5726-5734页

作者： Xinlin Zha Mengjuan Zuo Guilin Xu zhong yan Haining You Yi Xiong Ying Liu Yingying Li Liyan yang Ke Liu Mufang Li Tao Zhao Dong Wang College of Chemistry and Chemical Engineering Donghua UniversityShanghai 201620China Key Laboratory of Textile Fiber and Products Ministry of EducationWuhan Textile UniversityWuhan 430200China

The current landscape of chiral covalent organic frameworks(COFs)predominantly centered on constructing asymmetric molecular-scale chirality,often introducing an inherent contradiction to the COF symmetry and limiting ***,we overcome these challenges by achieving chiral transfer between one-dimensional(1D)imine linear polymers(LPs)and two-dimensional(2D)networkβ-ketoenamine COFs composed of achiral *** successfully synthesize several 1D imine LPs with mesoscopic helical chirality,comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription *** the irreversible tautomerism mechanism within the linker replacement approach,terephthalaldehyde(TPA)units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol(TP),yielding the corresponding 2D networkβ-ketoenamine *** and helicity of the resultantβ-ketoenamine COFs intimately hinge on reaction conditions,including the aldehyde stoichiometry of Tp and TPA,as well as the quantity and concentration of the catalyst *** optimized conditions,the nucleation and growth were precisely governed,achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D networkβ-ketoenamine COFs,even with covalent bond rupture,recombination,and topological transition(from[C2+C2]to[C3+C2]).Impressively,the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D networkβ-ketoenamine *** study not only offers new perspectives on the development of chiral functional COFs,but also provides fresh insights into the precise control of COFs'microscopic morphology.

关键词： chiral covalent organic frameworks chiral transfer dimensional transformation helicity

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北魏均田制与土地兼并问题再探

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史学集刊 2024年第5期 97-107页

作者：严耀中上海师范大学人文学院上海200234

北魏均田制包含着同一等级内之均平和等级之间分田不均的两面性,这体现着以权力为背景的土地之身份占有权,也是土地被多层次兼有在制度上之反映。其结果之一是导致大土地合法占有的同时,在一定程度上抑制了土地兼并。谴责土地兼并,在历... 详细信息

北魏均田制包含着同一等级内之均平和等级之间分田不均的两面性,这体现着以权力为背景的土地之身份占有权,也是土地被多层次兼有在制度上之反映。其结果之一是导致大土地合法占有的同时,在一定程度上抑制了土地兼并。谴责土地兼并,在历史上一向被视为政治正确,也令均田制往往获得赞扬。其实,均田制的推行,一方面容纳了以权力为后盾的直接或间接占有大土地现象在中国的延续,另一方面也阻碍了通过生产要素流转而使资源得到优化配置,并加重了行政操作成本。因此,均田制是一个效费比很低的制度。由此亦可发现其中一些所谓的“地主”往往只是一种权位所附带的身份。

关键词：北魏均田制土地兼并

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我国猪流行性腹泻流行现状与防控进展

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黑龙江畜牧兽医 2024年第7期 7-10,17页

作者：颜忠北京大北农科技集团股份有限公司北京100080

猪流行性腹泻(porcine epidemic diarrhea,PED)是由猪流行性腹泻病毒(Porcine epidemic diamhea virus,PFDV)引起的以猪只呕吐、腹泻、脱水和生长缓慢为主要特征的猪传染性肠道疾病,自2010年底在我国大范围暴发以来,给我国养猪业带来毁... 详细信息

猪流行性腹泻(porcine epidemic diarrhea,PED)是由猪流行性腹泻病毒(Porcine epidemic diamhea virus,PFDV)引起的以猪只呕吐、腹泻、脱水和生长缓慢为主要特征的猪传染性肠道疾病,自2010年底在我国大范围暴发以来,给我国养猪业带来毁灭性打击,造成巨大的经济损失,目前已成为我国养猪业最大的威胁之一。文章综述了我国猪流行性腹泻的流行现状及主要的防控措施,以期为我国猪流行性腹泻的防控提供参考。

关键词：猪流行性腹泻流行现状预防控制肠道疾病

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中国共产党民族政策与中华民族大团结

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内蒙古社会科学 2024年第1期45卷 17-25页

作者：王延中中国社会科学院民族学与人类学研究所北京100087

中国共产党及党的历代领导人都高度重视中华民族大团结和中华儿女大团结,在不同历史时期皆将其作为党的统一战线工作尤其是民族工作的重要内容,形成了中国共产党促进中华民族团结进步的基本经验:积极探索适合我国国情的解决民族问题的... 详细信息

中国共产党及党的历代领导人都高度重视中华民族大团结和中华儿女大团结,在不同历史时期皆将其作为党的统一战线工作尤其是民族工作的重要内容,形成了中国共产党促进中华民族团结进步的基本经验:积极探索适合我国国情的解决民族问题的正确道路、始终强调国家统一和民族团结、推动党的民族理论和民族政策不断创新和发展、明确铸牢中华民族共同体意识的主线地位、确立以中华民族大团结推进中国式现代化和中华民族伟大复兴的目标任务。

关键词：中国共产党民族政策民族大团结中华民族共同体意识中华民族共有精神家园

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科学阐释中华民族发展史的开创性成果——《中华民族共同体概论》读后

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中南民族大学学报（人文社会科学版） 2024年第7期44卷 10-17页

作者：王延中中国社会科学院民族学与人类学研究所中国社会科学院铸牢中华民族共同体意识研究基地

“铸牢中华民族共同体意识”是习近平总书记的重大原创性理论。在“铸牢中华民族共同体意识”这一理论提出和形成过程中,相关工作随即展开。如国家民委直属高校率先开设了“中华民族共同体概论”课程,学术界也在努力推动中华民族共同体... 详细信息

“铸牢中华民族共同体意识”是习近平总书记的重大原创性理论。在“铸牢中华民族共同体意识”这一理论提出和形成过程中,相关工作随即展开。如国家民委直属高校率先开设了“中华民族共同体概论”课程,学术界也在努力推动中华民族共同体的研究走向深入,从理论主题、体系框架、内在逻辑、概念范畴等方面,推进习近平总书记关于加强和改进民族工作重要思想的系统性、学理性阐发,阐明铸牢中华民族共同体意识的科学内涵、精神实质、实践要求。

关键词：直属高校国家民委原创性理论中华民族共同体科学阐释理论主题体系框架概念范畴

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