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Direct observation of interlayer coherent acoustic phonon dynamics in bilayer and few-layer PtSe2

Photonics Research 2019年第12期7卷 1416-1424页

作者： XIN CHEN SAIFENG ZHANG LEI WANG YI-FAN HUANG HUIYAN LIU JIAWEI HUANG NINGNING DONG WEIMIN LIU IVAN MKISLYAKOV jean michel NUNZI LONG ZHANG JUN WANG Laboratory of Micro-Nano Optoelectronic Materials and Devices Key Laboratory of Materials for High-Power LaserShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of High Field Laser Physics CAS Center for Excellence in Ultra-intense Laser ScienceShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China STU&SIOM Joint Laboratory for Superintense Lasers and the Applications Shanghai 201210China Department of Physics Engineering Physics&Astronomy and Department of ChemistryQueen's UniversityKingstonK7L-3N6 OntarioCanada State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

This work reports the real-time observation of the interlayer lattice vibrations in bilayer and few-layer PtSe_2 by means of the coherent phonon method. The layer-breathing mode and standing wave mode of the interlayer vibrations are found to coexist in such a kind of group-10 transition metal dichalcogenides(TMDCs). The interlayer breathing force constant standing for perpendicular coupling(per effective atom) is derived as 7.5 N/m,2.5 times larger than that of graphene. The interlayer shearing force constant is comparable to the interlayer breathing force constant, which indicates that PtSe2 has nearly isotropic interlayer coupling. The low-frequency Raman spectroscopy elucidates the polarization behavior of the layer-breathing mode that is assigned to have A1 g symmetry. The standing wave mode shows redshift with the increasing number of layers, which successfully determines the out-of-plane sound velocity of PtSe2 experimentally. Our results manifest that the coherent phonon method is a good tool to uncover the interlayer lattice vibrations, beyond the conventional Raman spectroscopy limit. The strong interlayer interaction in group-10 TMDCs reveals their promising potential in high-frequency(~terahertz) micro-mechanical resonators.

关键词： polarization interlayer coherent

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New C-13 Norisoprenoids and Flavonoids from Lannea kerstingii

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Journal of Materials Science and Chemical Engineering 2022年第10期10卷 10-19页

作者： jean-michel Kouamé Koffi Philomène Akoua Yao-Kouassi Chardin Seri Seri Abdulmagid Alabdul Magid Zachée Louis Evariste Akissi Laurence Voutquenne-Nazabadioko Université Félix Houphouë t-Boigny Laboratoire de Constitution et Réaction de la Matière UFR Sciences des Structures de la Matière et de Technologie Abidjan C&#244 te d’Ivoire Université de San Pedro San Pedro C&#244 te d’Ivoire Université de Reims Champagne-Ardenne CNRS Reims France

Lannea kerstingii is known for its multiple therapeutic and biological activities. Despite of many traditional uses of this plant, scientific research on the content of its chemical compounds is still limited. This study aims to isolate the chemical compounds contained in the n-butanol fraction of Lannea kerstingii leaves. The chemical investigation of the leaves of Lannea kerstingii led to isolation of three undescribed C-13 norisoprenoids, lankerstinol A-C (1-3), together with six (4-9) known flavonoid glycosides. The structures of these compounds were established by spectroscopic analyses.

关键词： Lannea kerstingii Anacardiaceae Flavonoids C-13 Norisoprenoids Structure Elucidation

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Cross-flow analysis of injection wells in a multilayered reservoir

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Petroleum 2016年第3期2卷 273-281页

作者： Mohammadreza Jalali jean-michel Embry Francesco Sanfilippo Frederic J.Santarelli Maurice B.Dusseault Geological Institute ETH ZurichZurichSwitzerland Baker Hughes AberdeenUnited Kingdom Geomec Environmental Management AS StavangerNorway Earth&Environmental Sciences Department University of WaterlooWaterlooONCanada

During fluid injection into a multilayered reservoir,a different pressure gradient is generated across the face of each permeable *** pressure gradient generates driving forces in the wellbore during well shut-in that causes the injected fluid moves from higher pressure layers to lower pressure layers,a phenomenon known as interwell ***-flow behavior depends on the initial pressure in the permeable layers and may be referred to as natural cross-flow(identical or natural initial pressures)and forced cross-flow(different initial pressures because of exploitation).Cross-flow may induce sand production and liquefaction in the higher pressure layers as well as formation damage,filter cake build-up and permeability reduction in the lower pressure ***,understanding cross-flow during well shut-in is important from a production and reservoir engineering perspective,particularly in unconsolidated or poorly consolidated sandstone *** and forced cross-flow is modeled for some injection wells in an oil reservoir located at North *** solution uses a transient implicit finite difference approach for multiple sand layers with different permeabilities separated by impermeable shale *** and forced cross-flow rates for each reservoir layer during shut-in are calculated and compared with different production logging tool(PLT)*** appears that forced cross-flow is usually more prolonged and subject to a higher flow rate when compared with natural cross-flow,and is thus worthy of more detailed analysis.

关键词： Cross-flow Multilayered Sandstone reservoir Sand production Skin factor

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Perception of Local Populations of Bouba-Ndjidda National Park on Indigenous Knowledge and the Impact of Climate Change on Biodiversity Conservation

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Open Journal of Ecology 2023年第11期13卷 865-881页

作者： Ghislain Noé Kougoum Piebeng Samuel Christian Tsakem Kalgongbe Kiebfiene Tikela Bakwo Fils Eric Moise Simon Awafor Tamungang michel Babale jean-Pierre Mate Mweru Isaac Diansambu Makanua Bouba Hotta Vincent Zoalang Mala Krossy Mavakala Raoul Sambieni Kouakou Baudouin michel Department of Biological Sciences Faculty of Science University of Maroua Maroua Cameroon Garoua Wildlife School Garoua Cameroon Department of Forestry and Wildlife Management College of Technology University of Bamenda Bamenda Cameroon Regional Post-Graduate Training School on Integrated Management of Tropical Forests and Lands Kinshasa Democratic Repub-lic of the Congo Faculty of Science University of Kinshasa Kinshasa Democratic Republic of the Congo

This study deals with the perceptions of indigenous knowledge in the field of conservation and the impact of climate change on biodiversity in the peripheral villages of the Bouba-Ndjidda National Park (PNBN), Department of Mayo-Rey, Cameroon. To this end, 23 out of 70 villages in the study area were selected, for a sample of 368 households surveyed through a questionnaire addressed to the heads of households. Data collection took place from August 27 to December 22, 2022. The results reveal that 70.7% of the population living near the PNBN practice agriculture as their main income-generating activity, followed by livestock (23.3%) and trade (6%). Knowledge in the field of the conservation of natural resources is rooted in occultism through rituals and sacrifices (99.50%) offered to the geniuses of nature and prohibitions on the felling of trees and sacred animals (13.00%). The populations perceive climate change through the variation of the seasons (97.60%), the increase in temperature (84.80%), the reduction in the duration of the rainy seasons (54.60%), the drop in agricultural yield (84.80%) and floods (74.70%). The consequence of these changes on wildlife is the disappearance of animal species such as the Rhinoceros, the Wild Dog, the Cheetah and the Ostrich. In order to cope with climate change, the natives have developed strategies such as the adoption of early crop varieties (maize, millet, soybeans, etc.), the reorganization of the agricultural calendar, the practice of reforestation, extension of field surfaces, the cessation of excessive deforestation and uncontrolled bush fires, the construction of fired brick houses, the practice of irrigation, seasonal migration and occultism. This indigenous knowledge is a perfect adaptation to climate change and makes it possible to better take into account the vision of local populations in the conservation of biodiversity.

关键词： Perception Indigenous Knowledge Climate Change Biodiversity Conservation Bouba-Ndjidda National Park

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Layer-modulated two-photon absorption in MoS2:probing the shift of the excitonic dark state and band-edge

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Photonics Research 2019年第7期7卷 77-85页

作者： Yafeng Xie Saifeng Zhang Yuanxin Li Ningning Dong Xiaoyan Zhang Lei Wang Weimin Liu Ivan M.Kislyakov jean-michel Nunzi Hongji Qi Long Zhang Jun Wang Laboratory of Micro-Nano Optoelectronic Materials and Devices and CAS Key Laboratory of Materials for High-Power Laser Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Department of Physics Engirteering Physics & Astronomy and Department of ChemistryQueen's University Kingston Ontario K7L-3N6Canada State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 China

Questions hovering over the modulation of bandgap size and excitonic effect on nonlinear absorption in twodimensional transition metal dichalcogenides (TMDCs) have restricted their application in micro/nano optical modulator, optical switching, and beam shaping devices. Here, degenerate two-photon absorption (TPA) in the near-infrared region was studied experimentally in mechanically exfoliated MoS2 from single layer to multilayer. The layer-dependent TPA coefficients were significantly modulated by the detuning of the excitonic dark state (2p). The shift of the quasiparticle bandgap and the decreasing of exciton binding energy with layers were deduced, combined with the non-hydrogen model of excitons in TMDCs and the scaling rule of semiconductors. Our work clearly demonstrates the layer modulation of nonlinear absorption in TMDCs and provides support for layer-dependent nonlinear optical devices, such as optical limiters and optical switches.

关键词： absorption layer-dependent bandgap

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Transient and etiology-related transcription regulation in cirrhosis prior to hepatocellular carcinoma occurrence

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World Journal of Gastroenterology 2009年第3期15卷 300-309页

作者： Frédérique Caillot Céline Derambure Paulette Bioulac-Sage Arnaud Franois michel Scotte Odile Goria Martine Hiron Maryvonne Daveau jean-Philippe Salier Inserm Unité 905 and Institut Fédératif de Recherches Multidisciplinaires sur les Peptides Faculté de Médecine-Pharmacie76183 RouenFrance Service d'Anatomie Pathologique Centre Hospitalier Universitaireand Inserm U88933000 BordeauxFrance Département Pathologie Centre Hospitalier Universitaire76183 RouenFrance Service de Chirurgie Générale et Digestive Centre Hospitalier Universitaire76183 RouenFrance Service d'Hépato-gastro-entérologie Centre Hospitalier Universitaire76183 RouenFrance

AIM:To search for transcription dysregulation that could(1) differentiate hepatocellular carcinoma(HCC)-free from HCC-related cirrhosis(2) differentiate HCC-free cirrhosis related to HCV from that related to alcohol ***:Using microarray analysis,we compared transcript levels in HCC-free cirrhosis(alcoholism:7;hepatitis C:7),HCC-associated cirrhosis(alcoholism:10;hepatitis C:10) and eight control *** identified transcripts were validated by qRT-PCR in an independent cohort of 45 samples(20 HCC-free cirrhosis;15 HCC-associated cirrhosis and 10 control livers).We also confirmed our results by *** which differentiated between alcoholic-related cirrhosis,HCV-related cirrhosis and control *** mainly corresponded to *** of Signal Transduction and Activator of Transcription-3(STAT-3) was found along with related changes in STAT-3 targets which occurred in an etiology-dependent fashion in HCC-free *** contrast,in HCC,such transcription dysregulations were not ***:We report that transcriptional dysregulations exist in HCC-free cirrhosis,are transiently observed prior to detectable HCC onset and may be appear like markers from cirrhosis to HCC transition.

关键词：肝疾病病理学酒精中毒肝炎病毒基因表达

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Hepatitis B virus mutations potentially conferring adefovir/ tenofovir resistance in treatment-naive patients

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World Journal of Gastroenterology 2009年第6期15卷 753-755页

作者： Rebecca Pastor Franois Habersetzer Samira Fafi-Kremer michel Doffoёl Thomas F Baumert jean-Pierre Gut Franoise Stoll-Keller Evelyne Schvoerer Laboratoire de Virologie CHRU de Strasbourg3 Rue Koeberlé67000 StrasbourgFrance Service d'Hépato-gastroentérologie Nouvel Hpital Civil1 Place de l'Hpital67091 StrasbourgFrance Inserm U 748 Strasbourg3 Rue Koeberlé67000 StrasbourgFrance Université Louis Pasteur Facultéde Médecine4 Rue Kirschleger67084 StrasbourgFrance

Anti-hepatitis B virus(HBV)therapy leads to the emer- gence of mutant viral strains during the treatment of chronic hepatitis B with nucleos(t)ides analogues. The existence of HBV variants with primary antiviral resistance may be important for treatment choice. We studied two patients with chronic HBV infection by sequencing the HBV polymerase *** had adefovir-and tenofovir-related mutations in the viral polymerase,although they had never been treated. These mutations were rtV214A/rtN238T in one patient and rtA194T in the ***,mutations in untreated patients deserve cautious *** data indicate that mutations that can theoretically confer adefovir or tenofovir resistance may emerge in treatmentnaive patients.

关键词：乙肝病毒变异体感染治疗方法

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INVOLVEMENT OF TRANSPORTERS IN NEUROTOXICITY

INVOLVEMENT OF TRANSPORTERS IN NEUROTOXICITY

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第十五届国际药理学大会

作者： Scherrmann jean-michel University Paris 5 INSERM U 705

＜正＞ The blood - brain barrier （BBB） and the blood - cerebrospinal fluid barrier （BCSFB）. are the first lines for protecting the brain. A complex network of transporters expressed at BBB and BCSFB participates to solute exchanges between blood and brain. Influx transporters belonging to the Solute Carrier super-family may facilitate the occurence of neurotoxic effects. Thus, the monocar-boxylate transporter MCT1 transports across BBB the recreational drug of abuse g - hydroxybutyrate leading to seizures, respiratory depression and impaired consciousness . In contrast, efflux transporters like P - glycoprotein （Pgp）. acts by pumping out endothelial cells towards the blood a wide variety of substrates including potential neurotoxic compounds. More recently, a second member, the Breast Cancer Resistance Protein （BCRP） was found co - localized with Pgp at BBB. The neuroprotective effect of these ABC transporters was demonstrated a-gainst xenobiotics like ivermectin. an antiparasite agent substrate of Pgp and dietary phototoxins which are substrates of BCRP. All these transporters play a critical role for protecting the brain from neurotoxic events.

关键词： neurotoxicity ABC SLC transporter

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THE PHYSICS AND TECHNOLOGY OF ORGANIC PHOTOVOLTAIC CELLS: DESIGNING EFFICIENT PLASTIC SOLAR CELLS

THE PHYSICS AND TECHNOLOGY OF ORGANIC PHOTOVOLTAIC CELLS: DE...

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第8届国际材联电子材料国际研讨会

作者： jean-michel Nunzi Laboratoire POMA UMR-CNRS 6136Université d’Angers France

＜正＞ Plastic photovoltaic solar cells represent a very attractive technology for the development of low cost renewable energy resources. The recent progresses, achieved using organic mono-crystal, multilayered thin film and interpentrated network technologies permit to expect a very fast increase in the conversion yield of organic solar cells, in order to make them a competitive alternative to the various forms of silicon cells. A cost reduction by an order of magnitude is expected with such technology. Such progress requires the development

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束流真空管道中放电现象的实验研究

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真空 2005年第5期42卷 39-41页

作者：宋洪 jean-michel LAURENT 中国科学院高能物理所北京100049 LHC CERN Geneva

目前正在欧洲核子中心(CERN)建造的LHC(L arge H adron Co llider)是世界上最大的加速器,它是一个具有高能量(7 T eV)大流强(0.53 A)的质子加速器。在它的直线节真空系统中,绝大部分的真空盒内表面将被镀上NEG薄膜。这样在又细又长的真... 详细信息

目前正在欧洲核子中心(CERN)建造的LHC(L arge H adron Co llider)是世界上最大的加速器,它是一个具有高能量(7 T eV)大流强(0.53 A)的质子加速器。在它的直线节真空系统中,绝大部分的真空盒内表面将被镀上NEG薄膜。这样在又细又长的真空盒里,当有束流通过时,NEG薄膜不仅可以作为分布式吸气剂泵使用,而且NEG薄膜还具有降低二次电子发射系数的作用,因此了解NEG薄膜的性能是很重要的。

关键词：真空盒的测试多次电子撞击 NEG薄膜激活温度

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