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Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions

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Petroleum Science 2024年第2期21卷 1122-1134页

作者： Guo-Dong Cheng Xue-Yu Pang Jin-Sheng Sun zheng-song Qiu Chuang-Chuang Wang Jian-Kun Qin Ning Li School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Oil and Gas Engineering Research Institute(Tarim Oilfield Company) China National Petroleum CorporationTarim841000XinjiangChina

The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength *** addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems.

关键词： Fly ash Long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)

microRNA-2184 orchestrates Mauthner-cell axon regeneration in zebrafish via syt3 modulation

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Journal of Genetics and Genomics 2024年第9期51卷 911-921页

作者： Xinghan Chen Yueru Shen zheng song Xinliang Wang Huaitong Yao Yuan Cai Zi-Ang Zhao Bing Hu Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefeiAnhui 230026China The First Affiliated Hospital of USTC Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China

MicroRNAs(miRNAs)play a significant role in axon regeneration following spinal cord ***,the functions of numerous miRNAs in axon regeneration within the central nervous system(CNS)remain largely ***,we elucidate the positive role of microRNA-2184(miR-2184)in axon regeneration within zebrafish Mauthner cells(M-cells).The upregulation of miR-2184 in a single M-cell can facilitate axon regeneration,while the specific sponge-induced silencing of miR-2184 leads to impeded *** show that syt3,a downstream target of miR-2184,negatively regulates axon regeneration,and the regeneration suppression modulated by syt3 depends on its binding to Ca2+.Furthermore,pharmacological stimulation of the cAMP/PKA pathway suggests that changes in the readily releasable pool may affect axon *** data indicate that miR-2184 promotes axon regeneration of M-cells within the CNS by modulating the downstream target syt3,providing valuable insights into potential therapeutic strategies.

关键词： Axon regeneration Axon ablation miR-2184 syt3 Readily releasable pool

Rational design multi-color-emissive chemiluminescent carbon nanodots in a single solvothermal reaction

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Nano Research 2024年第6期17卷 4651-4660页

作者： Guang-song zheng Cheng-Long Shen Yuan Deng Kai-Kai Liu Jin-Hao Zang Lin Dong Qing Lou Chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China

Recently,the chemiluminescence(CL)induced by carbon nanodots(CDs)has intrigued researchers’extensive interests in various applications due to its special light emission ***,the difficulty of synthesizing chemiluminescent CDs with full-spectrum emission severely hinders the further regulation of the CL emission ***,the multi-color-emissive chemiluminescent CDs are rational designed and further synthesized by regulating the sp2-hybrid core and sp3-hybrid surface from the citrate-ammonia molecular in a single solvothermal *** experimental characterizations and density functional theory calculations reveal that the higher temperature can promote the crosslinking polymerization/carbonization of carbon core and the higher protonation of solvent can determine the core size of final CDs,resulting in the variant CL emission from molecular-,crosslinking-and ***,the CL emission of the CDs can be further synthesized by tuning the luminescence chromophores in the formation process via regulating the temperature and solvent,enabling the applications of the CL CDs in illumination and information *** study paves a new technology to understand the luminescence of CDs and affords an industry translational potential over traditional chemiluminescent molecular.

关键词： carbon nanodots chemiluminescence regulation energy level alignment mechanism

Mechanism by which Rab5 promotes regeneration and functional recovery of zebrafish Mauthner axons

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Neural Regeneration Research 2025年第6期20卷 1816-1824页

作者： Jiantao Cui Yueru Shen zheng song Dinggang Fan Bing Hu Center for Advanced Interdisciplinary Science and Biomedicine of IHM Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina

Rab5 is a GTPase protein that is involved in intracellular membrane trafficking. It functions by binding to various effector proteins and regulating cellular responses, including the formation of transport vesicles and their fusion with the cellular membrane. Rab5 has been reported to play an important role in the development of the zebrafish embryo;however, its role in axonal regeneration in the central nervous system remains unclear. In this study, we established a zebrafish Mauthner cell model of axonal injury using single-cell electroporation and two-photon axotomy techniques. We found that overexpression of Rab5 in single Mauthner cells promoted marked axonal regeneration and increased the number of intra-axonal transport vesicles. In contrast, treatment of zebrafish larvae with the Rab kinase inhibitor CID-1067700markedly inhibited axonal regeneration in Mauthner cells. We also found that Rab5 activated phosphatidylinositol 3-kinase(PI3K) during axonal repair of Mauthner cells and promoted the recovery of zebrafish locomotor function. Additionally, rapamycin, an inhibitor of the mechanistic target of rapamycin downstream of PI3K, markedly hindered axonal regeneration. These findings suggest that Rab5 promotes the axonal regeneration of injured zebrafish Mauthner cells by activating the PI3K signaling pathway.

关键词： axonal regeneration Mauthner cell nerve regeneration Rab5 zebrafish

Tetraphenylethylene dicycle helicates:circularly polarized luminescence and chiral recognition based on emission wavelength change

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Science China Chemistry 2024年

作者： Zhi-Rong Xu Miao-Li Gao Ming Hu Wei Yu Yan-song zheng Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Chiral tetraphenylethylene(TPE) dicycle tetraaldehyde and TPE dicycle tetraacids bearing optically pure groups on the cycles were designed and synthesized. Due to the propeller-like conformation immobilization of TPE unit, this new class of TPE dicycle was resolved into M-and P-enantiomers, which could emit strong circular polarized luminescence(CPL). Interestingly,these TPE helicates displayed exceptional ability of molecule recognition. While the TPE dicycle tetraaldehyde could detect the microscale water in anhydrous tetrahydrofuran, the chiral TPE dicycle tetraacid could display different fluorescent color after interacting with two enantiomers of a wide variety of chiral amines including monoamines, diamines, and aminols, which could be applied to chiral recognition of these chiral amines. Furthermore, the emission wavelength of TPE dicycle tetraacid was found to change linearly with the enantiomer purity of chiral amine from enantiomer excess(ee) percent-100% to +100%, for the first time showing the potential for quantitative chiral analysis of chiral amines based on emission wavelength change. The emission wavelength was affected less by environmental factors than fluorescence intensity, which would enable the chiral analysis based on wavelength change with higher accuracy and repeatability.

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Neuroendocrine carcinoma of the common hepatic duct coexisting with distal cholangiocarcinoma:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1449-1460页

作者： Fei Chen Wei-Wei Li Juan-Fen Mo Min-Jie Chen Su-Hang Wang Shu-Ying Yang zheng-Wei song Department of Hepatobiliary Surgery The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Graduate School Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina The Key Laboratory The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Pathology The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Intensive Medicine The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND Neuroendocrine carcinoma(NEC)of the extrahepatic bile duct is very rare,and the treatment and prognosis are ***,we report the case of a middleaged female with primary large cell NEC(LCNEC)of the common hepatic duct combined with distal cholangiocarcinoma(dCCA).Additionally,after a review of the relevant literature,we summarize and compare mixed neuroendocrine-nonneuroendocrine neoplasm(MiNEN)and pure NEC to provide a reference for selecting the appropriate treatment and predicting the prognosis of this rare *** SUMMARY A 62-year-old female presented to the hospital due to recurrent abdominal pain for 2 *** examination showed mild tenderness in the upper abdomen and a positive Courvoisier *** tests showed elevated liver transaminase and carbohydrate antigen 199 *** examination revealed node dissection was performed,and hepatic duct tumours were unexpectedly found during *** suggested poorly differentiated LCNEC(approximately 0.5 cm×0.5 cm×0.4 cm),Ki-67(50%),synaptophysin+,and chromogranin A+.dCCA pathology suggested moderately differentiated *** patient eventually developed lymph node metastasis in the liver,bone,peritoneum,and abdominal cavity and died 24 months after *** sequencing methods were used to compare gene mutations in the two primary bile duct *** The prognosis of MiNEN and pure NEC alone is different,and the selection of treatment options needs to be differentiated.

关键词： Neuroendocrine carcinoma Mixed neuroendocrine-non-neuroendocrine neoplasm Cholangiocarcinoma Extrahepatic bile duct Case report

A retrospective analysis of mature T-and NK-cell lymphomas

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Cancer Biology & Medicine 2024年第3期21卷 223-229页

作者： Junlei Jia Xiaohui Wang zheng song Shen Meng Yue Fei Jingwei Yu Xia Liu Xue Han Lanfang Li Lihua Qiu zhengzi Qian Shiyong Zhou Wenchen Gong Bin Meng Xiubao Ren Xianhuo Wang Huilai Zhang National Key Laboratory of Druggability Evaluation and Systematic Translational Medicine and Department of LymphomaTianjin Medical University Cancer Institute&HospitalNational Clinical Research Center for CancerTianjin's Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinThe Sino-US Center for Lymphoma and Leukemia ResearchTianjin 300060China Department of Radiation Oncology Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical SciencesJinan 250117China Department of Pathology Department of Immunology/Biotherapy Tianjin Medical University Cancer Institute&HospitalNational Clinical Research Center for CancerTianjin's Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin 300060China

Mature T-and natural killer(NK)-cell lymphomas are heterogeneous groups of malignant lymphoid neoplasms arising from T and NK cells. The incidence of mature T-and NK-cell lymphomas is 2.1 per 100,000 people, according... 详细信息

关键词： lymphoma neoplasms killer

第37届中国化学奥林匹克(初赛)有机试题解析

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化学教育（中英文） 2024年第9期45卷 118-124页

作者：宋正华郑州外国语学校河南郑州450001

从基本概念、常见反应类型和机理出发,对第37届中国化学奥林匹克(初赛)有机试题进行了解析,以供读者参考。

关键词：化学奥林匹克有机试题反应机理

多空间尺度下土地利用类型对长三角地区水质的影响研究

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长江流域资源与环境 2024年第3期33卷 537-546页

作者：卢薪宇宋正姗李建江苏师范大学地理测绘与城乡规划学院江苏徐州221006 南京信息工程大学遥感与测绘工程学院江苏南京210044

为深入探究不同空间尺度以及不同水情条件下,长三角地区水质空间格局与土地利用类型关系,选取了2021年316个测站的溶解氧浓度、pH值、总氮浓度、总磷浓度、高锰酸盐指数、水温、氨氮浓度、电导率和浊度等9个水质指标月平均数据,以测站... 详细信息

为深入探究不同空间尺度以及不同水情条件下,长三角地区水质空间格局与土地利用类型关系,选取了2021年316个测站的溶解氧浓度、pH值、总氮浓度、总磷浓度、高锰酸盐指数、水温、氨氮浓度、电导率和浊度等9个水质指标月平均数据,以测站为中心,划分500、2 000 m缓冲区及子流域缓冲区,采用综合因子评价法、Pearson相关性分析和冗余分析等方法研究水质空间分布特征及土地利用类型影响。结果表明:(1)长三角整体水质较优,为Ⅱ级,主要污染物为氮磷和有机物,其中西南地区总磷浓度高,东北地区低;(2)同时,该区域水质枯水期和丰水期差异明显,表现为枯水期电导率、总氮和溶解氧均高于丰水期;(3)土地利用类型对水质影响明显,小尺度上,影响水质的主要土地类型为农业用地;此外,林地对水质影响在枯水期较丰水期强。在大尺度上,林地对区域水质影响较大。因此,小区域尺度上开展合理的农业措施管理和大区域尺度实施退耕还林还湖等措施对长三角地区水体生态治理具积极意义。

关键词：长三角水质评价土地利用时空尺度