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Experimental study of the effects of a multistage pore-throat structure on the seepage characteristics of sandstones in the Beibuwan Basin:Insights into the flooding mode

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Petroleum Science 2024年第2期21卷 1044-1061页

作者： Lei Wang xiao Lei Qiao-Liang Zhang Guang-Qing Yao Bo Sui xiao-Jun Chen Ming-Wei Wang Zhen-Yu Zhou Pan-Rong Wang xiao-Dong Peng Zhanjiang Branch China National Offshore Oil Corporation(CNOOC)LimitedZhanjiang524057GuangdongChina Faculty of Earth Resources China University of Geosciences(Wuhan)Wuhan430074HubeiChina School of Resources and Safety Engineering Chongqing UniversityChongqing400044China School of Engineering University of ManchesterManchester M139WJUK Hainan Branch China National Offshore Oil Corporation(CNOOC)LimitedHaikou570311HainanChina

To investigate the relationship between grain sizes, seepage capacity, and oil-displacement efficiency in the Liushagang Formation of the Beibuwan Basin, this study identifies the multistage pore-throat structure as a crucial factor through a comparison of oil displacement in microscopic pore-throat experiments. The two-phase flow evaluation method based on the Li-Horne model is utilized to effectively characterize and quantify the seepage characteristics of different reservoirs, closely relating them to the distribution of microscopic pores and throats. It is observed that conglomerate sandstones at different stages exhibit significant heterogeneity and noticeable differences in seepage capacity, highlighting the crucial role played by certain large pore throats in determining seepage capacity and oil displacement efficiency. Furthermore, it was found that the displacement effects of conglomeratic sandstones with strong heterogeneity were inferior to those of conventional homogeneous sandstone, as evidenced by multiple displacement experiments conducted on core samples with varying granularities and flooding systems. Subsequently, core-based experiments on associated gas flooding after water flooding were conducted to address the challenge of achieving satisfactory results in a single displacement mode for reservoirs with significant heterogeneity. The results indicate that the oil recovery rates for associated gas flooding after water flooding increased by 7.3%-16.4% compared with water flooding alone at a gas-oil ratio of approximately 7000 m^(3)/m^(3). Therefore, considering the advantages of gas flooding in terms of seepage capacity, oil exchange ratio, and the potential for two-phase production, gas flooding is recommended as an energy supplement mode for homogeneous reservoirs in the presence of sufficient gas source and appropriate tectonic angle. On the other hand, associated gas flooding after water flooding is suggested to achieve a more favorable develop

关键词： Beibuwan Basin Multistage pore-throat structure Multistage seepage characteristics Microscopic visualization Heterogeneity Gas/water flooding Flooding mode

Effect of coenzyme Q10 supplementation on post-vitrification mouse embryo development

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Asian pacific Journal of Reproduction 2024年第3期13卷 126-132页

作者： Anisa-Annur S Wan-Hafizah wj Nor-Ashikin MNK Muhammad-Zaki R Faculty of Pharmacy and Health Sciences Royal College of Medicine PerakUniversiti Kuala Lumpur30450 IpohPerakMalaysia Maternofetal and Embryo Research Group Faculty of MedicineUniversiti Teknologi MARASelangor BranchSungai Buloh Campus47000 Sungai BulohSelangorMalaysia

Objective:To investigate the effects of coenzyme Q10(CoQ10)supplementation on post-vitrification embryo development and gross ***:Balb/c mouse embryos were cultured in potassium simplex optimised medium(KSOM)with varying CoQ10 concentrations[0(control),20,40,and 60μM].The most effective CoQ10 concentration(40μM)was selected for subsequent post-vitrification morphology *** were randomly divided into four groups:Group A(non-vitrified without CoQ10),Group B(non-vitrified with CoQ10),Group C(vitrified without CoQ10),and Group D(vitrified with CoQ10),followed by vitrification at the 8-cell *** rates and development until the blastocyst stage were evaluated through morphological examinations using ASEBIR's system,distinguishing normal and abnormal ***:Supplementation of 40μM CoQ10 significantly increased blastocyst formation(95%)compared to the control group(92%),20μM(62%),and 60μM(56%)(P<0.001).Following vitrification,Group D exhibited a significant increase in blastocyst formation(92%)compared to Group C(82%)(P<0.05).Morphological assessments indicated superior embryo quality in Group B over Group D during the cleavage stage,morula,and blastocyst(P<0.05).Conclusions:CoQ10 supplementation exhibits promising potential to enhance preimplantation embryo development,increase blastocyst formation rates,and improve embryo quality *** offers a promising approach to mitigate oxidative stress on embryos,potentially improving overall assisted reproductive technology outcomes.

关键词： Coenzyme Q10 Antioxidant Embryo development Vitrification Morphology Assisted reproductive technology

THE BOUNDARY INTEGRO-DIFFERENTIAL EQUATIONS OF A BIHARMONIC BOUNDARY VALUE PROBLEM

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Journal of Computational Mathematics 1999年第1期17卷 59-72页

作者： Ban, HD Tang, wj Inst Appl Phys & Computat Math Lab Computat Phys Beijing 100088 Peoples R China Tsing Hua Univ Dept Appl Math Beijing 100084 Peoples R China

In this paper, a new method of boundary reduction is proposed, which reduces the biharmonic boundary value problem to a system of integro-differential equations on the boundary and preserves the self-adjointness of the original problem. Moreover, a boundary finite element method based on this integro-differential equations is presented and the error estimates of the numerical approximations are given. The numerical examples show that this new method is effective.

关键词： boundary integro-differential equations biharmonic boundary value problem

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家禽红螨(鸡皮刺螨)的意义及防治

养禽与禽病防治 2024年第4期 25-40页

作者： O.A.E.Sparagano D.R.George D.wj.Harrington A.Giangaspero 刘红(校对) Faculty of Health and Life Sciences Northumbria UniversityNewcastle upon Tyne NE18STUnited Kingdom Poultry Division Chr.Hansen A/S2970 HorsholmDenmark Dipartimento di Scienze Agrarie degli Alimenti e dell'AmbienteUniversita di Foggia71121Italy 默沙东动物保健品(上海)有限公司

家禽红螨(鸡皮刺螨)严重威胁世界各地的家禽生产和母鸡健康。鸡皮刺螨不但逐渐被认为是疫病重要的载体,而且有越来越多的报告显示其还可攻击包括人类在内的其他宿主,可见这种害虫对经济的影响变得越来越严重。随着世界各地的家禽生产逐... 详细信息

家禽红螨(鸡皮刺螨)严重威胁世界各地的家禽生产和母鸡健康。鸡皮刺螨不但逐渐被认为是疫病重要的载体,而且有越来越多的报告显示其还可攻击包括人类在内的其他宿主,可见这种害虫对经济的影响变得越来越严重。随着世界各地的家禽生产逐渐脱离传统的笼养方式,鸡皮刺螨在禽群中的影响将变得更加普遍,防控将变得更加困难。尽管已有耐药性和治疗失败的报告,但鸡皮刺螨的防治仍以合成杀螨剂为主。目前在鸡皮刺螨及螨虫管理的专项研究报告中已经提出一些替代防治措施。尽管许多替代防治措施仍处于商业化前期阶段,但仍有部分措施已经逐渐进入市场。本综述汇集了日益扩充的鸡皮刺螨的研究,并评估了其当前和未来可供选择的防控措施。得出的结论是,鸡皮刺螨防治的重大进展最有可能来自综合防控的措施,将最新的研究融入到现有的和新型的防治策略中,这种融合将改进的监测和建模相结合,更好地为治疗和干预该病提供信息支持。

关键词：鸡母鸡体外寄生虫兽医害虫防治

BOUNDARY ELEMENT APPROXIMATION OF STEKLOV EIGENVALUE PROBLEM FOR HELMHOLTZ EQUATION

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Journal of Computational Mathematics 1998年第2期16卷 165-178页

作者： Tang, wj Guan, Z Han, HD Inst Appl Phys & Computat Math Lab Computat Phys Beijing 100088 Peoples R China Tsing Hua Univ Dept Appl Math Beijing 100084 Peoples R China

Steklov eigenvalue problem of Helmholtz equation is considered in the present paper. Steklov eigenvalue problem is reduced to a new variational formula on the boundary of a given domain, in which the self-adjoint property of the original differential operator is kept and the calculating of hyper-singular integral is avoided. A numerical example showing the efficiency of this method and an optimal error estimate are given.

关键词： Steklov eigenvalue problem differential operator error estimate boundary element approximation

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芜菁种质资源根肿病抗性鉴定及组织显微观察

农业生物技术学报 2024年第1期32卷 80-90页

作者：雷霆刘晓乐周晓青杨昕蕾惠麦侠西北农林科技大学园艺学院/陕西省蔬菜工程技术研究中心

根肿病(clubroot disease)是十字花科作物主要病害之一，筛选芜菁(Brassica rapa ssp. rapifera)抗根肿(clubroot resistance, CR)材料，明确其抗根肿病基因分布和观察抗病组织的显微机理，对抗病品种选育具有重要的意义。本研究以25份... 详细信息

根肿病(clubroot disease)是十字花科作物主要病害之一，筛选芜菁(Brassica rapa ssp. rapifera)抗根肿(clubroot resistance, CR)材料，明确其抗根肿病基因分布和观察抗病组织的显微机理，对抗病品种选育具有重要的意义。本研究以25份芜菁资源为材料，采用人工苗期接种的方法对根肿病的抗性进行鉴定，利用分子标记检测抗病基因位点分布，通过荧光桃红染色和石蜡切片技术观察根肿菌(Plasraodiophora brassicae)侵染进程和根部病理变化。鉴定结果显示，4份材料表现抗病(免疫和高抗)，其中wj-9、wj-21和wj-22表现为免疫，wj-14表现高抗；另外wj-10、wj-13和wj-18共3份表现耐病；18份材料表现感病(感病和高感)。抗病基因在供试材料中分布由多到少依次为：Crr3(分布13个材料中)>CRb>Crr1a=CrrA5>CRc>Crr1>CRa(分布2个材料中)，wj-22检测到抗病基因最多，含6个。根肿菌在抗、感芜菁中的侵染进程和根部病理变化存在差异，抗病材料比感病材料发生根毛侵染时间晚、侵染率低，无皮层侵染；感病材料根部细胞膨大，结构紊乱并挤压破坏根部导管，而抗病材料细胞结构完整。对根肿病表现抗性的芜菁材料，聚合了较多抗病基因和致密的细胞结构。本研究鉴定到4份免疫和高抗根肿病芜菁资源，明确了其携带的抗病基因，探究了抗和感病材料的根肿菌侵染进程和组织结构差异，为利用其培育根肿病持久抗性品种提供了科学依据。

关键词：芜菁根肿病抗性鉴定分子检测显微观察

THE NUMERICAL SOLUTION OF FIRST KIND INTEGRAL EQUATION FOR THE HELMHOLTZ EQUATION ON SMOOTH OPEN ARCS

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Journal of Computational Mathematics 2001年第5期19卷 489-500页

作者： Tang, wj Fu, HY Shen, LJ Inst Appl Phys & Computat Math Lab Computat Phys Beijing 100088 Peoples R China

Presents a study which proposed a numerical solution of first kind integral equation for the Helmholtz equation on smooth open arcs. Quadrature method used; Numerical examples.

关键词： Helmholtz equation quadrature method

GATIS score for predicting the prognosis of rectal neuroendocrine neoplasms:A Chinese multicenter study of 12-year experience

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World Journal of Gastroenterology 2024年第28期30卷 3403-3417页

作者： Xin-Yu Zeng Ming Zhong Guo-Le Lin Cheng-Guo Li Wei-Zhong Jiang Wei Zhang Li-Jian Xia Mao-Jun Di Hong-Xue Wu xiao-Feng Liao Yue-Ming Sun Min-Hao Yu Kai-Xiong Tao Yong Li Rui Zhang Peng Zhang Department of Gastrointestinal Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430074Hubei ProvinceChina Department of Gastrointestinal Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Department of General Surgery Peking Union Medical College HospitalPeking Union Medical CollegeBeijing 100730China Department of Colorectal Surgery Fujian Medical UniversityFuzhou 350401Fujian ProvinceChina Department of Colorectal Surgery Changhai HospitalShanghai 200433China Department of Gastrointestinal Surgery The First Affiliated Hospital of Shandong First Medical UniversityJinan 250118Shandong ProvinceChina Department of Gastrointestinal Surgery Taihe HospitalHubei University of MedicineShiyan 442099Hubei ProvinceChina Department of Gastrointestinal Surgery I Section Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina Department of General Surgery Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang 441021Hubei ProvinceChina Department of Colorectal Surgery Jiangsu Province HospitalNanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Gastrointestinal Surgery School of MedicineShanghai Jiao Tong UniversityShanghai 200127China Department of General Surgery Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080Guangdong ProvinceChina Department of Colorectal Surgery Liaoning Cancer HospitalShenyang 110042Liaoning ProvinceChina

BACKGROUND There is currently a shortage of accurate,efficient,and precise predictive instruments for rectal neuroendocrine neoplasms(NENs).AIM To develop a predictive model for individuals with rectal NENs(R-NENs)using data from a large *** Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in *** forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival,and two nomograms were *** A total of 1408 patients with R-NENs were *** grade,T stage,tumor size,age,and a prognostic nutritional index were important risk factors for *** GATIS score was calculated based on these five *** overall survival prediction,the respective C-indexes in the training set were 0.915(95%confidence interval:0.866-0.964)for overall survival prediction and 0.908(95%confidence interval:0.872-0.944)for progression-free survival *** to decision curve analysis,net benefit of the GATIS score was higher than that of a single *** time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time *** The GATIS score had a good predictive effect on the prognosis of patients with R-NENs,with efficacy superior to that of the World Health Organization grade and TNM stage.

关键词： Rectal neuroendocrine neoplasm Nomogram Random forest Prognosis Overall survival Progression-free survival

Leakage in Mold Slit during Inverse Solidification

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Journal of University of Science and Technology Beijing 2001年第2期8卷 101-104页

作者： Zhang, JM Wang, XH Wang, wj Univ Sci & Technol Beijing Met Sch Beijing 100083 Peoples R China

The liquid steel will be leaked from the slit between the bottom of solidification mold and mother sheet during inversion casting process. By substitution of the actual liquid steel, the Ph-Sn alloy and the numerical simulation can be used to study the fluid flow in the inversion solidification mold, the mother sheet critical speed is determined for preventing the leakage from the slit of bottom. When the mother sheet speed is more than 0.06 m/s, Pb-Sn liquid alloy will not leak from the slit of the mold. Otherwise, the Ph-Sn liquid alloy can leak from the slit of the mold.

关键词： leakage slit inverse solidification mold