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SYNTHESIS AND PROPERTIES OF HOMOPOlYMER AND COPOlYMERS OBTAINED FROM 1-OCTADECENE WITH ZIRCONOCENE CATAlYSTS

Chinese Journal of Polymer Science 2000年第3期18卷 249-254页

作者： Raul Quijada juan l.Guevara Rene Rojas Franco M.Rabagliati Departamento de Ingenieria Quimica Facultad de Ciencias Fisicasy MatematicasUniversidad de ChileCasilla 2777SantiagoChile Departamento Ciencias Quimicas Facultad Quimicay BiologiaUniversidad de Santiago de ChileCasilla 40SantiagoChile

Studies related to the behavior of different metallocene catalysts for the homopolymerization of 1-octadecene andits copolymerization with ethylene will be *** metallocenes:rac-Et(Ind)_(2)ZrCl_(2),rac-Me_(2)Si(Ind)_(2)ZrCl_(2)andPh_(2)C(Flu)(Cp)ZrCl_(2)were chosen for the homopolymerization *** show important differences in catalytic activity athigh temperatures(≥70℃),with rac-Et(Ind)_(2)ZrCl_(2)showing the highest *** lower temperatures(≤30℃)thedifferences are *** the copolymerization of ethylene with 1-octadecene only the catalysts rac-Et(Ind)_(2)ZrCl_(2)andrac-Me_(2)Si(Ind)_(2)ZrCl_(2)were *** results show that their catalytic activity is just like that for the homopolymerizationof 1-octadecene,with higher activity for the metallocene with the Et-bridged catalyst.^(13)C-NMR analysis shows that thecomposition of the copolymerization products depends on the catalytic *** obtained with rac-Me_(2)Si(Ind)_(2)ZrCl_(2)have greater comonomer *** analysis shows that poly-1-octadecene synthesized withthe catalyst rac-Et(Ind)_(2)ZrCl_(2)is very dependent on the polymerization *** homopolymer obtained at 70℃presents two endothermal peaks at 41℃and 53℃,as compared with the one obtained at 30℃which presents one wider peakwith a maximum at 67℃.For the catalyst rac-Me_(2)Si(Ind)_(2)ZrCl_(2)this trend is not *** type of metallocene and thereaction time do not significantly change the intrinsic viscosity,but the polymerization temperature changes it drastically,giving higher values at lower *** measurements on the copolymers show that an increase of comonomerconcentration in the feed reduces the molecular weight of the copolymer,and it was also found that for homopolymer,themolecular weight is independent of the catalytic systems.

关键词： Homopolymerization Copolymerization Metallocene Catalytic activity Poly-l-octadecene

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Appraisal of treatment outcomes in integrative medicine using metabonomics:Taking non-alcoholic fatty liver disease with spleen deficiency syndrome as an example

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Journal of Integrative Medicine 2022年第6期20卷 524-533页

作者： liang Dai Jing-juan Xu Wen-jun Zhou Ai-ping lü Guang Ji Clinical Research Academy Peking University Shenzhen HospitalPeking UniversityShenzhen 518032Guangdong ProvinceChina Institute of Digestive Disease Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Department of Integrated Traditional and Western Medicine Jinling HospitalSchool of MedicineNanjing UniversityNanjing 210002Jiangsu ProvinceChina Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghai 201203China School of Chinese Medicine Hong Kong Baptist UniversityHong Kong 999077China

Objective:Appraisal of treatment outcomes in integrative medicine is a challenge due to a gap between the concepts of Western medicine(WM)disease and traditional Chinese medicine(TCM)*** study presents an approach for the appraisal of integrative medicine that is based on targeted *** use non-alcoholic fatty liver disease with spleen deficiency syndrome as a test ***:A patient-reported outcome(PRO)scale was developed based on literature review,Delphi consensus survey,and reliability and validity test,to quantitatively evaluate spleen deficiency ***,a metabonomic foundation for the treatment of non-alcoholic fatty liver disease with spleen deficiency syndrome was identified via a longitudinal interventional trial and targeted ***,an integrated appraisal model was established by identifying metabolites that responded in the treatment of WM disease and TCM syndrome as positive outcomes and using other aspects of the metabonomic foundation as independent ***:Ten symptoms and signs were included in the spleen deficiency PRO *** internal reliability,content validity,discriminative validity and structural validity of the scale were all *** on treatment responses to treatments for WM disease(homeostasis model assessment of insulin resistance)or TCM syndrome(spleen deficiency PRO scale score)from a previous randomized controlled trial,two cohorts comprised of 30 participants each were established for targeted metabolomics ***-five metabolites were found to be involved in successful treatment outcomes to both WM and TCM,following quantitative comparison and multivariate ***,the model of the integrated appraisal system was exploratively established using binary logistic regression;it included 9 core metabolites and had the prediction probability of 83.3%.Conclusion:This study presented a new and comprehensive research route for integrative appraisal of treatment

关键词： Complementary and alternative medicine Integrative medicine Patient-reported outcome measures Metabolomics Non-alcoholic fatty liver disease Spleen deficiency syndrome

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Bacterial extracts and bioformulates as a promising control of fruit body rot and root rot in avocado cv. Hass

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Journal of Integrative Agriculture 2020年第3期19卷 748-758页

作者： David GRANADA lorena lÓPEZ-lUJAN Sara RAMIREZ-RESTREPO juan MORAlES Carlos PElÁEZ-JARAMIllO Galdino ANDRADE juan Carlos BEDOYA-PEREZ Phytosanitary and Biological Control Unit Corporation for Biological ResearchMedellin 050034Colombia Faculty of Health Sciences Institution University Colegio Mayor de AntioquiaMedellin 050034Colombia Department of Agronomic Sciences National University of ColombiaMedellin 050034Colombia Faculty of Exact Sciences University of AntioquiaMedellin 050010Colombia Department of Microbiology Londrina State UniversityLondrina 86051-990Brazil

At least 20-40% of annual losses of avocado crops are caused by pathogenic *** chemical treatments of these diseases are inefficient,cause environmental pollution and are increasingly restricted by international *** work aimed to assess the biocontrol capacity of a bacterial extract to protect avocado fruits and plants from pathogen *** from the bacterial isolate Serratia ***5.1 were obtained from liquid fermentations in a biorreactor.A body rot postharvest infection model with Colletotrichum gloeosporioides on fruits was ***,packaging conditions were simulated using the bacterial extract and the commercial fungicide prochloraz as a positive ***,seedlings infections with Phytophthora cinnamomi were performed on two types of avocado(West Indian race and ***).The Area Under Disease Progress Curve(AUDPC) was recorded using the bacterial extract and a commercial product with fosetyl-aluminium as *** bacterial extract significantly reduced infections by *** on injured avocado fruits at 31.1 μg ml^-*** fruits were also protected against body rot infections at the same concentration and showed no significant differences with the commercial *** the other hand,AUDPC in the seedlings was significantly reduced with the extract treatment at 3 μg ml^-1 compared to the ***,a possible phytotoxicity effect of the extract was evidenced in the seedlings and confirmed by pathogen recovery and tests on Raphanus sativus ***,formulations of the extracts(emulsion and emulsifiable concentrate) were prepared,and bioactive stability was assessed for 8 *** emulsion formulates demonstrated very stable bioactivity against *** extract and the emulsion formulate showed promising results for the control of avocado *** bioproducts based on this type of active principles could be developed for the benefit of avocado industry.

关键词： Colletotrichum gloeosporioides Phytophthora cinnamomi Serratia sp. antagonistic microbes secondary metabolites biofungicide

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Electrochemical and spectroscopic study of interfacial interactions between chalcopyrite and typical flotation process reagents

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International Journal of Minerals,Metallurgy and Materials 2016年第2期23卷 127-136页

作者： Gustavo Urbano Isabel lázaro Israel Rodríguez juan luis Reyes Roxana larios Roel Cruz Instituto de Metalurgia Universidad Autonotrla de San Luis PotosiAvSierra Leona 550Lomas 2a SeccionSan Luis PotosiS.L.P.78210Mexico Industrial Minera Mexico S.A.de C.V. San Luis PotosiS.L.P.Mexico Centro Universitario de Ciencias Exactas e Ingenierias Universidad de GuadalajaraGuadalajaraJaliscoMexico

Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite（CuFeS2） and n-isopropyl xanthate（X） in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH *** spectroscopy,Fourier transform infrared（FTIR） spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this *** results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate ***,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.

关键词： sulfide minerals chalcopyrite xanthates flotation interfacial reactions electrochemistry spectroscopy

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Fetal vs adult mesenchymal stem cells achieve greater gene expression, but less osteoinduction

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World Journal of Stem Cells 2015年第1期7卷 223-234页

作者： juan E Santiago-Torres Rebecca lovasz Alicia l Bertone Comparative Orthopedic Research laboratory Department of Veterinary Clinical Sciences College of Veterinary Medicine The Ohio State University Columbus OH 43210 United States College of Medicine The Ohio State University Columbus OH 43210 United States

AIM: To investigate adenoviral transduction in mesenchymal stem cells(MSCs) and effects on stemness in vitro and function as a cell therapy in ***: Bone marrow-derived adult and fetal MSC were isolated from an equine source and expanded in monolayer tissue culture. Polyethylenimine(PEI)-mediated transfection of pc DNA3-e GFP or adenoviral transduction of green fluorescent protein(GFP) was evaluated in fetal MSCs. Adenoviral-mediated transduction was chosen for subsequent experiments. All experiments were carried out at least in triplicate unless otherwise noted. Outcome assessment was obtained by flow cytometry or immunohystochemistry and included transduction efficiency, cell viability, stemness(i.e., cell proliferation, osteogenic and chondrogenic cell differentiation), and quantification of GFP expression. Fetal and adult MSCs were then transduced with an adenoviral vector containing the gene for the bone morphogenic protein 2(BMP2). In vitro BMP2 expression was assessed by enzyme linked immunosorbent assay. In addition, MSC-mediated gene delivery of BMP2 was evaluated in vivo in an osteoinduction nude mouse quadriceps model. New bone formation was evaluated by microradiography and ***: PEI provided greater transfection and viability in fetal MSCs than other commercial chemical reagents. Adenoviral transduction efficiency was superior to PEI-mediated transfection of GFP in fetal MSCs(81.3% ± 1.3% vs 35.0% ± 1.6%, P lar in adult MSCs(78.1% ± 1.9%). Adenoviral transduction provided significantly greater expression of GFP in fetal than adult MSCs(7.4 ± 0.1 vs 4.4 ± 0.3 millions of mean fluorescence intensity units, P ll as significantly greater in vitro BMP2 expression(0.16 pg/cell-day vs 0.10 pg/cell-day, P l MSC GFP positive cells decreased significantly faster than adult MSCs(1.15% ± 0.05% vs 11.4% ± 2.1% GFP positive at 2 wk post-transduction, P ll proliferation and osteo

关键词： Mesenchymal stem cells Biomarkers Next generation sequencing Diagnostic tool Tumor-initiating cells

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Modeling of Microstructure Evolution in 22MnB5 Steel during Hot Stamping

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Journal of Iron and Steel Research International 2014年第2期21卷 197-201页

作者： li-juan ZHU Zheng-wei GU Hong XU Yi l Jiang CHAO College of Materials Science and Engineering Jilin University Technology Center Changchun Railway Vehicles Co.Ltd. Advanced Manufacture Technology Center Academy of Machinery Science and Technology

Automobile manufacturers have been inereasingl^r adopting hot-stamped parts for use in newly designed ve- hicles to improve crash worthiness and fuel efficiency. However, the simulation of hot stamping is rather complex and challenging, and further research still needs to be done on hot stamping hardening mechanism. The microstruc- ture evolution and hardening mechanisms during hot stamping of 22MnB5 steel were thoroughly investigated, using information provided in the literatures as well as experimental results. New models were developed to predict the grain growth during heating and the flow stress of a manganese boron steel （22MnB5） with high hardenability by the Gleeble simulation experimental results. The deformed austenite decomposition during stamping and quenching was emphatically quantified based on the transformation thermodynamic and kinetic theories, and the relationship of mi- crostructure to properties was analyzed. The results showed that the optimal process to obtain homogeneous and small lath martensite is heating at 900--950 ℃ for 5 min and then auenching at 50 ℃/s with a Dressing time about 8 s.

关键词： 22MnBS hot stamping, transformation martensite

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Virus location and lymphocyte Apoptosis in lymph Nodes of Piglets Infected with PCV-2

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Agricultural Sciences in China 2008年第4期7卷 507-512页

作者： SHI lū-juan HAN Hui-li ZHANG Shu-xia College of Veterinary Medicine Nanjing Agricultural University Nanjing 210095 P.R.China

The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ （PCV-2）. Nine 32-day-old conventional piglets free of infection with PCV-2 were used, and distributed into three groups： control group （n = 3）, piglets inoculated with PCV-2 alone （PCV-2, n = 3）, and PCV-2 inoculated and KlH immunostimulated group （PCV-2 ＋ KlH, n = 3）. Superficial inguinal lymph nodes from all piglets were collected for histological examination after 32 days postinoculation, and immunohistochemistry for PCV-2 detection. location of apoptotic cells was detected with TdT-mediated dUTP nick end labeling （TUNEl） and cell cycle, and the apoptotic rates were measured by flow cytometry. The characteristic histopathological lesions of the piglets in PCV-2 and PCV-2 ＋ KlH were lymphocyte depletions in the cortex and paracortex of the lymph nodes, epithelioid-like macrophage infiltration, and intracytoplasmic inclusion bodies presented in epithelioid-like macrophages. PCV-2 was mainly found in epithelioid-like macrophages by immunohistochemistry. In the lymph nodes, lymphocytes presented higher apoptotic rates in the cortex by TUNEl, special B-cell areas, and similar apoptotic cells were found in this compartment in the control. The apoptotic rates of the lymph nodes were 0.41, 3.34, and 4.88% in the control, PCV-2, and PCV-2 ＋ KlH groups by flow cytometry, respectively. The apoptotic rates of lymph nodes for PCV-2 and PCV-2 ＋ KlH piglets were significantly higher than those for the control group （P〈0.05 and P〈0.01）. The proliferation index （PI） was 0.17_＋0.01, 0.12_＋0.01 and 0.12_＋0.04 in the control, PCV-2, and PCV-2 ＋ KlH group, the PI of the control group was higher than that of the other groups, but without the statistical difference. PCV-2 can induce lymphocyte depletion in lymph nodes of piglets by blocking cell proliferation and promoting apoptosis. This is one of th

关键词： apoptosis virus located lymph node PCV-2 piglets

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Quantification and timing of porosity evolution in tight sand gas reservoirs:an example from the Middle Jurassic Shaximiao Formation,western Sichuan,China

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Petroleum Science 2015年第2期12卷 207-217页

作者： Zheng-Xiang lü Su-juan Ye Xiang Yang Rong li Yuan-Hua Qing State Key laboratory of Oil and Gas Reservoir Geology &Exploitation Chengdu University of Technology Exploration and Production Research Institute Sinopec Southwest Chengdu Institute of Geology and Mineral Resources PetroChina Tarim Oilfield Company

The diagenesis and porosity evolution of the Middle Jurassic Shaximiao sandstones were analyzed based on petrographic observations, X-ray diffractometry, scanning electron microscopy observations, carbon and oxygen stable isotope geochemistry, fluid inclusion mi- crothermometry, and thermal and burial history modeling results. The point count data show that secondary pores （av. 5.5 %） are more abundant than primary pores （av. 3.7 %） and are thus the dominant pore type in the Shaximiao sandstones. Analysis of porosity evolution indicates that alteration of sandstones mainly occurred during two paragenetic stages. Mechanical compaction and cementa- tion by early chlorite, calcite, and quartz typically decrease the depositional porosity （40.9 %） by an average of 37.2 %, leaving porosity of 3.7 % after stage I （〈85 ℃, 175-145 Ma）. The original intergranular porosity loss due to compaction is calculated to be 29.3 %, suggesting that mechanical compaction is the most significant diagenetic process in primary porosity destruction. Stage II can be further divided into two sub-stages （Stage IIa and Stage IIb）. Stage IIa （85-120 ℃, 145-125 Ma） is characterized by late dissolution, which enhanced porosity by 8.8 %, and the porosity increased from 3.7 % to 12.5 %. During stage IIb （〉120 ℃, 125-0 Ma）, the precipitation of late chlorite, calcite, quartz, and kaolinite destroyed 3.3 % porosity, leaving porosity of 9.2 % in the rock today.

关键词： Diagenesis Porosity evolution -Tight gas sandstones Jurassic Western Sichuan

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Moving object extraction based on saliency detection and adaptive background model

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Optoelectronics letters 2020年第1期16卷 59-64页

作者： SUN Pei-ye lülian-rong QIN juan School of Electrical and Electronic Engineering Tianjin University of TechnologyTianjin 300384China

For the ghost in visual background extractor(Vi Be)algorithm and the influence of dynamic background,an improved Vi Be algorithm is proposed to extract moving object in this *** way of background acquisition during modeling is improved to eliminate the *** the saliency of the pre-M-frame,and synthetic relatively real *** with the background can avoid the generation of *** selection of thresholds in the model is improved to reduce the impact of the dynamic *** the thresholds adaptively according to the background *** addition,find the inner contour of extracted object to fill,which makes the detected targets more *** results show that the presented algorithm effectively removes ghosts and enhances anti-interference *** with several existing methods,the presented algorithm has better performance.

关键词： ghost algorithm remove

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Pleistocene history of Iberomys,an endangered endemic rodent from southwestern Europe

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Integrative Zoology 2014年第4期9卷 481-497页

作者： Gloria CUENCA-BESCÓS juan Manuel lÓPEZ-GARCÍA María Angeles GAlINDO-PEllICENA Rosa GARCÍA-PEREA Julio GISBERT juan ROFES Jacint VENTURA Research Group Aragosaurus-IUCA PaleontologyEarth Sciences DepartmentUniversity of ZaragozaZaragozaSpain Research Group of Paleobiology and Prehistory Human Studies DepartmentUniversity of FerraraFerraraItaly Research Institute of Evolution and Human Behavior UCM-ISCIIIMadridSpain GAlEMIA Conservation and Study of Forgotten VertebratesMadridSpain Department of Stratigraphy and Paleontology Faculty of Sciences and TechnologyUniversity of the Basque CountryGipuzkoaGuipúzcoaSpain Department of Animal Biology Plant Biology and EcologyFaculty of BiosciencesUniversity Autonoma de BarcelonaBarcelonaSpain

The extant Cabrera’s vole,Microtus cabrerae,differs in morphology and evolutionary history from the other species of *** arvicoline has unique derived features in the cranium,mandible and ***bly its most conspicuous features are its large size,the high skull in lateral view,the long and distally broad nasals,and the triangle shape of the anteroconid complex,with a marked labio-lingual asymmetry of the occlusal surface of the first lower *** this study,we propose a phylogenetic lineage that includes Cabrera’s vole in what until now has been the Microtus subgenus *** information and several life history traits support the elevation of Iberomys to the rank of *** Iberomys comprises species that have appeared in succession during the Quaternary:in the Early Pleistocene,the extinct *** in the Middle Pleistocene,the extinct *** and in the late Pleistocene,the extant ***,the extant species shows several biological singularities,such as multiple polymorphic copies of the SRY male-specific gene in both males and females,and the lowest basal metabolic rate in relation to weight among arvicoline ***,its habitat requirement is unique among the Iberian ***,the biological and paleontological data that we present in this work support the elevation of its taxonomic rank to that of ge*** study also suggests a modification of nomenclature:Microtus(Iberomys)brecciensis is replaced with *** and the common name of the extant M.(I.)cabrerae changed from‘topillo’to‘iberon’to improve conservation and protection actions.

关键词： Cabrera’s vole conservation Iberoccitanian endemism Iberomys origin

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