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Chinese Journal of Polymer Science 2020年第3期38卷 220-230,I0005页

作者： Simona Losio laura Boggioni Massimiliano Cornelio Abbas Razavi Incoronata Tritto CNR–Istituto di Scienze e Tecnologie Chimiche"G.Natta"(CNR-SCITeC) via Alfonso Corti 12-20133 MilanoItaly Total Petrochemicals Research Zone Industrielle CB-7181 FeluyBelgium

ethylene-propene copolymers have been synthesized by three C1-symmetric metallocene molecules(1,2,and 3),having tert-butyl substituents on the Cp moiety,on the fluorenyl moiety,or on both moieties,and methylaluminoxane(MAO)at different polymerization temperatures and monomer *** were investigated by 13 C-NMR,1 H-NMR,and SeC analyses.A relationship was found between[eee]/[e]ratios and copolymer molar masses in each series:the higher the[eee]/[e]ratio,the lower the copolymer molar *** parity of[eee]/[e]ratio,copolymer molar mass follows the order 1>>3>*** end group analysis reveals that copolymers mainly terminate when propene is the last inserted unit,confirming that it is the greater facility of Mt-P-e-poly(e-co-P)to terminate that influences the copolymer molar *** the catalysts considered,catalyst 1,which gives syndiospecific polypropene,gives greater activities,comonomer incorporation,and molar *** 3,which gives isospecific polypropene,in copolymerization performs better than 2,having the same bridge,with respect to activities,ethylene content,and molar *** good performance of this catalyst arises from the not necessity of polymer chain to back skip when ethylene is the last inserted unit.

关键词： ethylene-propene Metallocene catalysts Copolymers Microstructure Molar masses

Use of a Microwave Plasma Process at Atmospheric Pressure for Bacterial Inactivation without Thermal effects

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Materials Sciences and Applications 2023年第5期14卷 285-298页

作者： laura Renoux Christelle Dublanche-Tixier Christophe Chazelas pascal Tristant Patrice Valorge Corinne Maftah Patrick Leprat University of Limoges CNRS IRCER UMR 7315 Limoges France University of Limoges E2Lim UR 24133 Limoges France

An atmospheric microwave plasma argon was used for the inactivation of bacteria e. coli. The employed device, called Axial Injection Torch (or TIA for Torche à Injection Axiale), consisted of a microwave power source, a waveguide and a gas supply system. Using this argon plasma source, we studied the effects of the exposure time, the exposure distance, the input power, and the gas flow rate on the reduction rate of escherichia coli cells. The first part of the study was carried out with a static sample exposed to the plasma and then in the second part the sample was set in motion relative to the plasma jet. A log reduction number of e. coli of 4 (10-4 CFU/mL) was obtained with UV and active species, for UV only a log of 1 (10-1 CFU/mL) was obtained.

关键词： Atmospheric Pressure Plasma Microwave Plasma Torch Disinfection Bacteria

Flipped classroom approach to global outreach:cross-cultural teaching of horizontal strabismus to Chinese ophthalmology residents

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International Journal of Ophthalmology(english edition) 2023年第2期16卷 280-285页

作者： Randy Lu Ryan e Dodge Ⅲ Jocelyn Lam laura enyedi Tammy Yanovitch Nandini Gandhi Leona Ding Michelle T Cabrera University of Washington School of Medicine SeattleWA 98195USA Department of Anesthesia Massachusetts General HospitalBostonMA 02114USA eyehealth Northwest PortlandOR 97209USA Department of Ophthalmology Duke UniversityDurhamNC 27708USA Department of Ophthalmology University of OklahomaOklahoma CityOK 73019USA Department of Ophthalmology University of California DavisSacramentoCA 95817USA Department of Ophthalmology University of WashingtonSeattleWA 98195USA Division of Ophthalmology Seattle Children’s HospitalSeattleWA 98105USA

AIM:To evaluate the flipped classroom model for teaching horizontal strabismus didactics in an ophthalmology residency program in China as part of a visiting professorship from the United ***:Residents from an ophthalmology residency program in China were invited to participate in flipped classroom sessions taught by an experienced American ophthalmology faculty in *** were instructed to watch a pre-class video lecture prior to the in-class-casebased *** tests(5 Ophthalmic Knowledge Assessment Program style questions)and surveys were administered before and after the classroom sessions(100%response rate).These results were compared to that of an American cohort who were taught the same ***:The Chinese cohort of 12 residents preferred the flipped classroom to the traditional classroom at higher rates than the American cohort of 40 residents(92%vs 55%,P=0.04)and felt that all ophthalmology topics would be appropriate for the flipped classroom teaching style(P-values between 0.008 andese and American cohorts,we found that the exotropia curriculum saw a small but significant improvement in performance following the flipped classroom session(P=0.025 for Chinese residents;P=0.001 for US residents),whereas scores in both groups for the esotropia course did not significantly ***:This is the first study to evaluate the flipped classroom model implemented by a visiting ophthalmology professor in a global outreach *** flipped classroom sessions are viewed favorably by the Chinese residents relative to the US cohort with a modest impact on *** in-person interpreter requirement and increased student engagement make this model valuable in cross-cultural visiting professorship ***,the flipped classroom may lend itself well to a virtual format to prevent the transmission of COVID-19,although such a format requires further study.

关键词： flipped classroom international ophthalmology residency graduate medical education China active learning medical education ophthalmology

Pancreaticβ-cell dysfunction in type 2 diabetes:Implications of inflammation and oxidative stress

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World Journal of Diabetes 2023年第3期14卷 130-146页

作者： Phiwayinkosi V Dludla Sihle e Mabhida Khanyisani Ziqubu Bongani B Nkambule Sithandiwe e Mazibuko-Mbeje Sidney Hanser Albert Kotze Basson Carmen Pheiffer Andre.pascal Kengne Biomedical Research and Innovation Platform South African Medical Research CouncilCape Town 7505South Africa Department of Biochemistry and Microbiology University of ZululandKwaDlangezwa 3880South Africa Department of Biochemistry North-West UniversityMmabatho 2745South Africa School of Laboratory Medicine and Medical Sciences University of KwaZulu-NatalDurban 4000South Africa Department of Physiology and environmental Health University of LimpopoSovenga 0727South Africa Department of Medicine University of Cape TownCape Town 7500South Africa Non-Communicable Diseases Research Unit South African Medical Research CouncilTygerberg 7505South Africa

Insulin resistance and pancreaticβ-cell dysfunction are major pathological mechanisms implicated in the development and progression of type 2 diabetes(T2D).Beyond the detrimental effects of insulin resistance,inflammation and oxidative stress have emerged as critical features of T2D that defineβ-cell *** markers of inflammation such as C-reactive protein,tumor necrosis factor alpha,and interleukin-1βare consistently associated withβ-cell failure in preclinical models and in people with ***,important markers of oxidative stress,such as increased reactive oxygen species and depleted intracellular antioxidants,are consistent with pancreaticβ-cell damage in conditions of *** effects illustrate a pathological relationship between an abnormal inflammatory response and generation of oxidative stress during the progression of *** current review explores preclinical and clinical research on the pathological implications of inflammation and oxidative stress during the development ofβ-cell dysfunction in ***,important molecular mechanisms and relevant biomarkers involved in this process are discussed to divulge a pathological link between inflammation and oxidative stress duringβ-cell failure in *** the clinical relevance of the review,a systematic analysis of evidence from randomized controlled trials is covered,on the potential therapeutic effects of some commonly used antidiabetic agents in modulating inflammatory makers to improveβ-cell function.

关键词： Type 2 diabetes Insulin resistance β-cell dysfunction Inflammation Oxidative stress

extracellular vesicles in liver disease and beyond

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World Journal of Gastroenterology 2018年第40期24卷 4519-4526页

作者： laura Morán Francisco Javier Cubero Department of Immunology Ophthalmology and ORLComplutense University School of MedicineMadrid 28040Spain 12 de Octubre Health Research Institute(imas12) Madrid 28041Spain

extracellular vesicles(eVs) are membrane-derived vesicles which can be released by different cell types, including hepatocytes, hepatic stellate cells and immune cells in normal and pathological conditions. eVs carry lipids, proteins, coding and non-coding RNAs and mitochondrial DNA causing modifications on the recipient cells. These vesicles are considered potential biomarkers and therapeutic agents for human diagnostic and prognostic due to their function as intercellular mediators of cell-cell communication within the liver and between other organs. However, the development and optimization of methods for eVs isolation is required to characterize their biological functions as well as their potential as a treatment option in the clinic. Nevertheless, many questions remain unanswered related to the function of eVs under physiological and pathological conditions. In the current editorial, the results obtained in different studies that investigated the role of intrahepatic eVs during liver diseases, including drug-induced liver injury, non-alcoholic fatty liver, nonalcoholic steatohepatitis, alcoholic liver disease and hepatocellular carcinoma and extrahepatic eVs in remote organs during pathological events such as pulmonary disease, cardiovascular diseases, neurodegenerative disorders e.g., Alzheimer's disease, Parkinson's disease and multiple sclerosis as well as in immunopathological processes, are discussed. Although much light needs to be shed on the mechanisms of eVs, these membranederived vesicles represent both a novel promising diagnostic, and a therapeutic tool for clinical use that we emphasize in the current editorial.

关键词： extracellular vesicles microRNA Hepatocytes Drug-induced liver injury Alcoholic liver disease Nonalcoholic fatty liver disease Non-alcoholic steatohepatitis Hepatocellular carcinoma

Fekete-Gauss Spectral elements for Incompressible Navier-Stokes Flows:The Two-Dimensional Case

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Communications in Computational Physics 2013年第5期13卷 1309-1329页

作者： laura Lazar Richard Pasquetti Francesca Rapetti Lab.J.A.Dieudonne UMR 7351 CNRS UNSUniversite de Nice-Sophia Antipolis06108 Nice Cedex 02France

Spectral element methods on simplicial meshes,say TSeM,show both the advantages of spectral and finite element methods,i.e.,spectral accuracy and geometrical *** present a TSeM solver of the two-dimensional(2D)incompressible Navier-Stokes equations,with possible extension to the 3D *** uses a projection method in time and piecewise polynomial basis functions of arbitrary degree in *** so-called Fekete-Gauss TSeM is employed,i.e.,Fekete(***)points of the triangle are used as interpolation(***)*** the sake of consistency,isoparametric elements are used to approximate curved *** resolution algorithm is based on an efficient Schur complement method,so that one only solves for the element boundary ***,the algebraic system is never assembled,therefore the number of degrees of freedom is not *** accuracy study is carried out and results are provided for classical benchmarks:the driven cavity flow,the flow between eccentric cylinders and the flow past a cylinder.

关键词： Spectral elements simplicial meshes Fekete-Gauss approximation Navier-Stokes equations projection methods domain decomposition

Identification and classification of transient pulses observed in magnetometer array data by time-domain principal component analysis filtering

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earthquake Science 2017年第4期30卷 193-207页

作者： Karl N. Kappler Daniel D. Schneider laura S. MacLean Thomas e. Bleier Quake Finder Palo AltoCA 94306USA

A method for identification of pulsations in time series of magnetic field data which are simultaneously present in multiple channels of data at one or more sensor locations is described. Candidate pulsations of interest are first identified in geomagnetic time series by inspection. Time series of these ＂training events＂ are represented in matrix form and transpose-multiplied to generate time- domain covariance matrices. The ranked eigenvectors of this matrix are stored as a feature of the pulsation. In the second stage of the algorithm, a sliding window （approxi- mately the width of the training event） is moved across the vector-valued time-series comprising the channels on which the training event was observed. At each window position, the data covariance matrix and associated eigen- vectors are calculated. We compare the orientation of the dominant eigenvectors of the training data to those from the windowed data and flag windows where the dominant eigenvectors directions are similar. This was successful in automatically identifying pulses which share polarization and appear to be from the same source process. We apply the method to a case study of continuously sampled （50 Hz） data from six observatories, each equipped with three- component induction coil magnetometers. We examine a 90-day interval of data associated with a cluster of four observatories located within 50 km of Napa, California, together with two remote reference stations-one 100 km to the north of the cluster and the other 350 km south. When the training data contains signals present in the remote reference observatories, we are reliably able to identify and extract global geomagnetic signals such as solar-generated noise. When training data contains pulsations only observed in the cluster of local observatories, we identify several types of non-plane wave signals having similar polarization.

关键词： Time series Magnetic fields Array data Signal processing Principal component analysis

Mature versus emerging technologies for CO2 capture in power plants： Key open issues in post-combustion amine scrubbing and in chemical looping combustion

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Frontiers of Chemical Science and engineering 2018年第2期12卷 315-325页

作者： Giorgia De Guido Matteo Compagnoni laura A. Pellegrini Ilenia Rossetti Department of Chemistry Materials and Chemical Engineering "Giulio Natta" Politecnico di Milano Piazza Leonardo da Vinci 32 20133 MilanItaly Department of Chemistry Universita degli Studi di Milano INSTM Unit Milano-Universita and CNR-ISTM Via Camillo Golgi 19 20133 Milan Italy

Carbon capture and storage （CCS） have acquired an increasing importance in the debate on global wanning as a mean to decrease the environmental impact of energy conversion technologies, by capturing the CO2 produced from the use of fossil fuels in electricity generation and industrial processes. In this respect, post-combustion systems have received great attention as a possible near-term CO2 capture technology that can be retrofitted to existing power plants. This capture technology is, however, energy-intensive and results in large equipment sizes because of the large volumes of the flue gas to be treated. To cope with the demerits of other CCS technologies, the chemical looping combustion （CLC） process has been recently considered as a solution for CO2 separation. It is typically referred to as a technology without energy penalty. Indeed, in CLC the fuel and the combustion air are never mixed and the gases from the oxidation of the fuel （i.e., CO2 and H2O） leave the system as a separate stream and can be separated by condensation of H2O without any loss of energy. The key issue for the CLC process is to find a suitable oxygen carrier, which provides the fuel with the activated oxygen needed for combustion. The aim of this work is to explore the feasibility of using perovskites as oxygen carriers in CLC and to consider the possible advantages with respect to the scrubbing process with amines, a mature post-combustion technology for CO2 separation.

关键词： CO2 capture monoethanolamine chemical looping combustion oxygen carder perovskites

Predictive power of tertiary lymphoid structure signature for neoadjuvant chemotherapy response and immunotherapy benefit in HeR2-negative breast cancer

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Cancer Communications 2023年第8期43卷 943-946页

作者： François Bertucci Alexandre De Nonneville.pascal Finetti emilie Mamessier11Laboratory of Predictive Oncology Label Team“Ligue contre le cancer”Cancer Research Center of MarseillePaoli-Calmettes InstituteAix-Marseille UniversityInserm UMR1068CNRS UMR725MarseilleFrance Department of Medical Oncology Paoli-Calmettes InstituteMarseilleFrance

Dear editor,Pembrolizumab,an immune checkpoint inhibitor(ICI),was recently approved for early-stage triple-negative breast cancer(eTNBC),and promising results have been reported in advanced hormone receptor-positive/human epidermal growth factor receptor 2-negative(HR+/HeR2-)and HeR2+BCs[1].Given the costs and potential toxicity,markers predictive of ICI benefits are ***,neither programmed death-ligand 1(PD-L1)expression nor other tested markers(i.e.,tumor mutational burden,microsatellite instability)effectively predict ICI benefit[2].Tertiary lymphoid structures(TLS)are secondary lymphoid organ-like aggregates that reside in the tumor microenvironment and are associated with clinical response to ICIs in metastatic melanoma,renal cell carcinoma.

关键词： lymphoid breast cancer

Finite-Size Conformational Transitions: A Unifying Concept Underlying Chromosome Dynamics

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Communications in Theoretical Physics 2014年第10期61卷 607-616页

作者： Bertrand R.Caré pascal Carrivain Thierry Forné Jean-Marc Victor Annick Lesne Laboratoire de Physique Théorique de la Matière Condensée CNRS UMR 7600UPMC University Paris 06F-75005ParisFrance CNRS GDR 3536 UPMC University Paris 06F-75005ParisFrance Institut de Génétique Humaine CNRS UPR 1142 MontpellierFrance Institut de Génétique Moléculaire de Montpellier CNRS UMR 5535University of MontpellierMontpellierFrance Kavli Institute for Theoretical Physics China CAS

Investigating average thermodynamic quantities is not sufficient to understand conformational transitions of a finite-size polymer. We propose that such transitions are better described in terms of the probability distribution of some finite-size order parameter, and the evolution of this distribution as a control parameter varies. We demonstrate this claim for the coil-globule transition of a linear polymer and its mapping onto a two-state model. In a biological context, polymer models delineate the physical constraints experienced by the genome at different levels of organization,from DNA to chromatin to chromosome. We apply our finite-size approach to the formation of plectonemes in a DNA segment submitted to an applied torque and the ensuing helix-coil transition that can be numerically observed, with a coexistence of the helix and coil states in a range of parameters. Polymer models are also essential to analyze recent in vivo experiments providing the frequency of pairwise contacts between genomic loci. The probability distribution of these contacts yields quantitative information on the conformational fluctuations of chromosome regions. The changes observed in the shape of the distribution when the cell type or the physiological conditions vary may reveal an epigenetic modulation of the conformational constraints experienced by the chromosomes.

关键词： coil-globule transition helix-coil transition chromosome conformational capture two-state model