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Polymorph and morphology of CaCO_3 in relation to precipitation conditions in a bubbling system

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1335-1342页

作者： Jian Sun lisheng wang Dongfang Zhao School of Chemistry and Chemical Engineering Beijing Institute of Technology

Simulating the typical carbonation step in a mineral CO_2 sequestration, precipitated calcium carbonate(PCC) was prepared by bubbling CO_2 gas into a rich Ca solution. These carbonation reactions were conducted at three p H ranges, namely 10.0–9.0, 9.0–8.0, and 8.0–7.0, in which temperature and CO_2 flow rate are additional experimental variables. The PCC obtained in experiments was examined by Fourier transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD). It was found that supersaturation determined by p H value and flow rate of CO_2 has significant influence on polymorph of PCC. Vaterite was preferably formed at high supersaturation, while dissolution of metastable vaterite and crystallization of calcite occurred at low supersaturation. High temperature is a critical factor for the formation of aragonite. At 70 °C, vaterite, calcite and aragonite were observed to coexist in PCC because transformation from vaterite to aragonite via calcite occurred at this temperature. Scanning electron microscopy(SEM) technology was performed on prepared PCC, and various morphologies consistent with polymorphs were observed.

关键词： Precipitated calcium carbonate Rich Ca solution Bubbling CO2 pH range Polymorph Morphology

Enthalpy of phase transition of isonicotinic acid

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Chinese Journal of Chemical Engineering 2017年第7期25卷 971-975页

作者： Dongfang Zhao Guanghui Liu Jian Sun lisheng wang School of Chemical Engineering and Environment Beijing Institute of TechnologyBelting 100081China

In this work, the group contribution method of Chickos et al. was applied to estimate the fusion enthalpy of isonicotinic acid, and the obtained result(29.2 k J·mol^(-1)) showed a large difference with the value(135 k J·mol^(-1)) as reported from literatures and as determined by differential scanning calorimetry(DSC). The results of DSC/TG measurement showed that the phase transition of isonicotinic acid from 187.27 °C to277.47 °C underwent a sublimation process, with a sublimation enthalpy of 128.03 k J·mol^(-1). An efficient analytical technique combining pyrolysis and gas chromatography/mass spectrometry(Py-GC/MS) was used to prove this conclusion.

关键词： lsonicotinic acid Enthalpy of fusion Group contribution method Enthalpy of sublimation Py-GC/MS

Centennial-scale monsoon collapses during Marine Isotope Stage(MIS)7e detected in a northern Chinese stalagmite record

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Science China Earth Sciences 2023年第12期66卷 2941-2952页

作者： Wuhui DUAN Ming TAN lisheng wang Xuefeng wang Zhibang MA Linlin CUI Zhengyi XIAO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Beijing 100029China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Occurrence or absence of centennial-scale climatic variability during Marine Isotope Stage(MIS)7e,the first peak interval of the Penultimate Interglacial,remains ambiguous due to the limited available high-resolved ***,we present a decadal-resolved stalagmiteδ^(18)O record from northern China spanning from 242.3 to 236.8 ka BP,covering *** composite KLSδ^(18)O record,integrating this study with the previous record in the same cave,shows a descending trend from TerminationⅢto MIS7e,which follows the increasing Northern Hemisphere summer insolation(NHSI).This observation further emphasizes the important influence of NHSI on the glacial/interglacial *** are more large-amplitude,millennial-to centennial-scale variability occurring during TerminationⅢcompared with MIS7e,implying that ice-sheet decay potentially plays an important role in climatic *** centennial-scale summer monsoon collapses,peaking at~242.1,~240.8,~239.3 and~238.2 ka BP,are detected in our new record,indicating the pervasiveness of the intra-interglacial climatic *** the lack of solar activity and freshwater outbursts data during MIS7e,it is not possible to conclude about the drivers of the identified abrupt climatic *** the dynamic mechanisms of sub-millennial climatic anomalous during early Holocene,we tentatively propose that slowdown of the meridional overturning circulation caused by freshwater fluxes into North Atlantic and/or attenuated solar irradiance is the potential forcing for the abrupt climate events within ***,attenuated solar irradiance could also result in climatic anomalies through low-latitude processes.

关键词： Northern China Stalagmiteδ~(18)O record Marine Isotope Stage(MIS)7e Centennial-scale monsoon collapses Freshwater and/or solar activity forcings

Re-evaluating the role of epithelial-mesenchymal-transition in cancer progression

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The Journal of Biomedical Research 2018年第2期32卷 81-90页

作者： Andrew Sulaiman Zemin Yao lisheng wang Department of Biochemistry Microbiology and Immunology Faculty of Medicine University of Ottawa China-Canada Centre of Research for Digestive Diseases Ottawa Institute of Systems Biology University of Ottawa Regenerative Medicine Program Ottawa Hospital Research Institute

Epithelial-mesenchymal transition（EMT） and mesenchymal-epithelial transition（MET） are essential for embryonic development and also important in cancer progression. In a conventional model, epithelial-like cancer cells transit to mesenchymal-like tumor cells with great motility via EMT transcription factors; these mesenchymallike cells migrate through the circulation system, relocate to a suitable site and then convert back to an epithelial-like phenotype to regenerate the tumor. However, recent findings challenge this conventional model and support the existence of a stable hybrid epithelial/mesenchymal（E/M） tumor population. Hybrid E/M tumor cells exhibit both epithelial and mesenchymal properties, possess great metastatic and tumorigenic capacity and are associated with poorer patient prognosis. The hybrid E/M model and associated regulatory networks represent a conceptual change regarding tumor metastasis and organ colonization. It may lead to the development of novel treatment strategies to ultimately stop cancer progression and improve disease-free survival.

关键词： Epithelial-mesenchymal transition(EMT) mesenchymal-epithelial transition(MET) hybrid EMT/MET cancer metastasis

Tanshinone IIA protects intestinal epithelial cells from ferroptosis through the upregulation of GPX4 and SLC7A11

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BIOCELL 2023年第5期47卷 1107-1115页

作者： HAN wang YANG SUN XIAOXU ZHANG XIAOYING wang YUJUN XIA lisheng wang School of Basic Medicine Qingdao UniversityQingdao266071China Laboratory of Molecular Diagnosis and Regenerative Medicine The Affiliated Hospital of Qingdao UniversityQingdao266000China Department of Hematology The Affiliated Hospital of Qingdao UniversityQingdao266000China Beijing Institute of Radiation Medicine Beijing100850China

Background:Inflammatory bowel disease(IBD)is a chronic inflammatory disease of the gastrointestinal *** destruction of the intestinal epithelial barrier is one of the major pathological processes in IBD *** evidence indicated that epithelial cell ferroptosis is linked to IBD and is considered a target ***:RAS-selective lethal 3(RSL3)was used to induce ferroptosis in intestinal epithelial cell line No.6(IEC-6)cells,and cell ferroptosis and the effects of tanshinone IIA(Tan IIA)were determined by cell counting kit-8(CCK-8),reactive oxygen species(ROS)staining,Giemsa staining and transmission electron microscope(TEM).The cell viability of natural product library compounds was determined by *** expression of ferroptosis-related genes were detected by real-time quantitative polymerase chain reaction(RT-qPCR)and western ***:Treatment of IEC-6 cells results in the accumulation of ROS and typical morphological characteristics of ***3 treatment caused rapid cellular cytotoxicity which could be reversed by ferrostatin-1(Fer-1)in IEC-6 *** product library screening revealed that Tan IIA is a potent inhibitor of IEC-6 cell *** IIA could significantly protect the RSL3-induced ferroptosis of IEC-6 ***,the ferroptosis suppressors,glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),and miR-17-92 were found to be early response genes in RSL3-treated *** of IEC-6 cells with Tan IIA resulted in upregulation of GPX4,SLC7A11,and ***:Our study demonstrated that Tan IIA protects IEC-6 cells from ferroptosis through the upregulation of GPX4,SLC7A11,and *** findings might provide a theoretical grounding for the future application of Tan IIA to treat or prevent IBD.

关键词： Tanshinone IIA GPX4 Ferroptosis Intestinal epithelial cells IBD

Human RBCs blood group conversion from A to O using a novel α-N-acetylgalactosaminidase of high specific activity

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Chinese Science Bulletin 2008年第13期53卷 2008-2016页

作者： YU ChengYu XU Hua wang lisheng ZHANG JianGeng ZHANG YangPei Department of Blood Molecular Biology Institute of Military Transfusion Academy of Military Medical Science Beijing 100850 China Shaanxi Blood Centre Xi'an 710061 China Department of Experimental Hematology Institute of Radiation Medicine Academy of Military Medical Science Beijing 100850 China

α-N-acetylgalactosaminidase (αNAGA) can convert group A human red blood cells (RBCs) to group O. One novel αNAGA gene was cloned by PCR from Elizabethkingia meningosepticum isolated from a domestic clinical sample. Pure recombinant αNAGA was obtained by genetic engineering and protein purification with a calculated molecule of 49.6 kD. αNAGA was selective for terminal α-N-acetylgalacto-samine residue with a high specific activity. αNAGA could completely remove A antigens of 1 U (about 100 mL) group A1 or A2 RBCs in 1 h at pH 6.8 and 25℃ with a consumption of 1.5 or 0.4 mg recombinant enzyme. Enzyme-converted group A RBCs did not agglutinate after being mixed with monoclonal anti-A or sera of groups A,B,AB and O. Other blood group antigens except ABO had no change. FCM analy-sis showed that A antigens and A1 antigens disappeared while H antigens increased. It indicated that αNAGA successfully converted human blood group A RBCs to universally transfusable group O RBCs without the risk of ABO-incompatible transfusion reactions. This αNAGA was suitable for producing universal RBCs to increase clinical transfusion safety,improve the RBCs supply,and to decrease transfusion cost and support transfusion service in case of emergency.

关键词：血型转换输血反应 A抗原免疫反应

Rare-earth element geochemistry reveals the provenance of sediments on the southwestern margin of the Challenger Deep

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Journal of Oceanology and Limnology 2019年第3期37卷 998-1009页

作者： JIANG Zuzhou SUN Zhilei LIU Zhaoqing CAO Hong GENG Wei XU Haixia wang lisheng wang Libo School of Geosciences China University of PetroleumQingdao 266580China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Key Laboratory of Marine Hydrocarbon Resources and Environmental Geology Ministry of Natural ResourcesQingdao Institute of Marine GeologyQingdao 266071China China Three Gorges New Energy Corp. Beijing 100053China Research Institute of Petroleum Exploration & Development PetroChinaBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The hadal zone represents one of the last great frontiers in modern marine science,and deciphering the provenance of sediment that is supplied to these trench settings remains a largely unanswered ***,we examine the mineralogical and geochemical composition of a sediment core(core CD-1)that was recovered from the southwestern margin of the Challenger Deep within the Mariana *** element abundances and rare-earth element patterns from these sediments require inputs from both terrigenous dust and locally sourced volcanic *** exploit a two-endmember mixing model to demonstrate that locally sourced volcanic material dominates the sediment supply to the Challenger Deep(averaging^72%).The remainder,however,is supplied by aeolian dust(averaging^28%),which is consistent with adjacent studies that utilized Sr-Nd isotopic *** on a growing database,we strengthen our understanding of Asian aeolian dust input into the northwestern Pacific,which ultimately improves our appreciation of sedimentation in,and around,the hadal zone.

关键词： Challenger Deep sediment rare-earth elements provenance Asian aeolian dust

Record of hydrothermal activity in the Yuhuang hydrothermal field and its implications for the Southwest Indian Ridge:evidence from sulfide chronology

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Acta Oceanologica Sinica 2023年第11期42卷 59-68页

作者： Weifang Yang Chunhui Tao Shili Liao Jin Liang Wei Li Teng Ding Ágata Alveirinho Dias Xuefeng wang lisheng wang Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China School of Oceanography Shanghai Jiaotong UniversityShanghai 200030China School of Marine Science and Engineering Nanjing Normal UniversityNanjing 210023China Institute of Science and Environment University of Saint JosephMacao 999078China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide ***,the sulfide chronology and hydrothermal activity of the YHF remain poorly *** this study,mineralogical analyses and 230Th/U dating were *** activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the *** 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the *** activity in the SWIR has been relatively active over the past20 *** contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in *** maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 *** was a slight positive correlation between the maximal age and estimated surface area or estimated *** minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic *** ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)*** results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.

关键词： Southwest Indian Ridge seafloor massive sulfides 230Th/U dating hydrothermal activity mass accumulation

The antioxidant trolox inhibits aging and enhances prostaglandin E-2 secretion in mesenchymal stem cells

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BIOCELL 2023年第2期47卷 385-392页

作者： XIAOXU ZHANG LIN ZHANG LIN DU HUIYAN SUN XIA ZHAO YANG SUN WEI wang lisheng wang Laboratory of Molecular Diagnosis and Regenerative Medicine Medical Research CenterThe Affiliated Hospital of Qingdao UniversityQingdao266000China Department of Hematology The Affiliated Hospital of Qingdao UniversityQingdao266000China School of Nursing Jilin UniversityChangchun130000China Yanda Medical Research Institute Hebei Yanda HospitalSanhe065201China

Mesenchymal stem cells(MSCs)have been widely used in regenerative medicine and clinical therapy due to their capabilities of proliferation,differentiation,and immune ***,during in vitro expansion,MSCs are prone to aging,which largely limits their *** E-2(PGE-2)is a key effector secreted by MSCs to exert immunomodulatory *** screening the compound library for PGE-2 secretion,the antioxidant trolox was verified as a stimulator of MSCs to secrete *** effect of antioxidant trolox on biological characteristics of MSCS,including aging,proliferation,and gene expression,was *** results demonstrated that trolox can resist aging,promote proliferation,and enhance PGE-2 secretion of MSCs without affecting their surface marker ***,trolox treatment up-regulates miR-17-92 clusters in MSCs and may contribute to its anti-aging ***,trolox addition might be beneficial for MSCs expansion and their application.

关键词： Mesenchymal stem cells(MSCs) Trolox Antioxidation Prostaglandin E-2