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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien G.Moreau jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

Predictive approach of heterogeneous catalysis

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National Science Review 2018年第5期5卷 633-635页

作者： j.an-marie basset jérémie D.A.Pelletier King Abdullah University of Science and Technology

‘Predictive catalysis’ or ‘catalysis by design’ has recently advanced heterogeneous catalysis by using the conceptual tool of surface fragments [1] such as ‘surface organometallic fragments’(SOMF)or ‘surface coordination fragments’(SCF) to achieve and understand a presumed catalytic cycle (see Fig. 1).One or several fragments of the molecule

关键词： SCF CR CO EXAFS

Preparation and Properties of Zirconium Hydrideon the surface of MCM-41 Mesoporous Molecular Sieves

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Chemical Research in Chinese Universities 2001年第4期17卷 426-431页

作者： WANG Xu-xu FU Xian-zhi LEFEBVRE Frederic basset j.an-marie Research Institute of Photocatalysis Fuzhou UniversityFuzhou 350002P.R.China Laboratoire de Chimie Organometallique de Surface UMR CNRS-CPE 998643Bd dull Novembre 11 Novembre 191869616 Villeurbanne CedexFrance

Zirconium monohydride bonded to the framework oxygen of MCM-41 surface was prepared by the reaction of tetraneopentyl zirconium with MCM-41 surface hydroxyl groups, followed by the hydrogenolysis of the resulted product. The surface hydride was characterized by using infrared spectroscopy, solid-state NMR, elemental analysis, gas-phase chromatography and chemical probing reaction. It was shown that this surface species is stable below 150 ’C and can catalytically crack alkanes into methane and ethane at 100 .

关键词： MCM-41 Zirconium hydride Grafting reaction Catalytic cracking

Modification of the adsorption and catalytic properties of micro-and mesoporous materials by reactions with organometallic complexes

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Science China Chemistry 2010年第9期53卷 1862-1869页

作者： LEFEBVRE Frédéric PUTAj Piotr basset j.an-marie Université de Lyon ICL C2P2 UMR 5265(CNRS-CPE-Université Lyon 1) LCOMS-CPE Lyon

This review describes the work of two laboratories in the field of the modification of micro-and mesoporous molecular sieves through reactions with organometallic *** modification of zeolites can occur inside the pore channels or on the external surface,depending on the size of the organometallic *** the modification occurs on the external surface,it results in a decrease of the pore entrance,which will lead in turn to a modification of the sorption properties of the zeolite,by decreasing the rate of the adsorption(mainly by a kinetic control).Such a material can be also used in catalysis,because the external acid sites,which are responsible for side-reactions,have been removed upon *** small organometallic complexes are used,they can fill the channels and cages of the zeolite and react with internal hydroxyl *** to the high acidity of zeolites,the reaction occurs very easily(for example at-100℃ on faujasite),in contrast to what is observed on the external surface,therefore leading to high metal *** that case,the modification of the sorption properties will be mainly related to a thermodynamic *** resulting materials can be useful in catalysis,by combining the activity of the organometallic complex and properties(for example shape-selectivity) of the *** of mesoporous molecular sieves occurs always in the pores and results in altering of the sorption properties of the solid,by changing the interaction type between the sorbent and the *** example the sorption isotherm of alkanes is changed from type II to type III according to the IUPAC nomenclature.

关键词： zeolites transition metals organometallic compounds adsorption properties

Epidemiological and Histopathological Profile of Prostate Cancer: A Retrospective Study in the Pathology Department of the University Clinics of Kinshasa

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journal of Cancer Therapy 2024年第6期15卷 239-249页

作者： Rive Lukuaku Buanza jérémie Okumadi Lukuke Fabrice Bokambandja Lolangwa Andy Mbangama Muela Matthieu Loposo Nkumu François Beya Kabongo Renault Kambere Sitamuina j.an-marie Mpolesha Kabongo Faculty of Medicine Bel Campus Technological University Kinshasa DRC Department of Pathological Anatomy University Clinics of Kinshasa Kinshasa DRC Gyneco-Obstetrics Department University Clinics of Kinshasa Kinshasa DRC Department of Surgery Urology University Clinics of Kinshasa Kinshasa DRC

Background: Prostate cancer, the most common male cancer, represents a real public health problem in terms of its frequency and severity in different countries around the world. It disproportionately affects people of African descent wherever they live in the world [1]. To the best of our knowledge, its extent and particularities in the African environment are not well known. Objective: To determine the epidemiological and histopathological profile of prostate cancer in the CUK anatomopathology department. Methodology: This is a retrospective study conducted at the University Clinics of Kinshasa Anapathology Department from january 1, 2015 to December 31, 2022, a period of 8 years. Word processing and tables were entered using the Hp brand computer, with Microsoft Office WORD 2016 software. Data analysis was performed with SPSS version 22.0 software. Results were presented in tables and figures. Results: Prostate was diagnosed in 132 cases, i.e. 1.58% of all CUK laboratory analyses and 8% of cancers diagnosed. The age group most affected was 66-75 years, i.e. 59% of all subjects. Adenocarcinoma was the most frequent histological type, and biopsy dominated in 111 cases (84.1%). Conclusion: Prostate cancer is a real public health problem. Worldwide, and in the Democratic Republic of Congo, it is the most frequently diagnosed cancer in men, and the leading cause of cancer-related death in men. In the DRC, because of the delay in consulting our patients and the weakness of systematic screening, patients are seen at an advanced stage of the disease. Treatment is multidisciplinary, involving surgery, radiotherapy and chemotherapy (including targeted therapies). Patient awareness and screening campaigns will help to considerably reduce the delay in diagnosis and the morbidity and mortality associated with prostate cancer.

关键词： Prostate Gleason Score Democratic Republic of Congo

Caspase-11 mediated inflammasome activation in macrophages by systemic infection of *** exacerbates arthritis

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International journal of Oral Science 2024年第03期 499-514页

作者： Tokuju Okano Hiroshi Ashida Noriko Komatsu Masayuki Tsukasaki Tamako Iida marie Iwasawa Yuto Takahashi Yasuo Takeuchi Takanori Iwata Miwa Sasai Masahiro Yamamoto Hiroshi Takayanagi Toshihiko Suzuki Department of Bacterial Pathogenesis Infection and Host Response Graduate School of Medical and Dental Sciences Tokyo Medical and Dental University Department of Immunology Graduate School of Medicine and Faculty of Medicine The University of Tokyo Department of Osteoimmunology Graduate School of Medicine and Faculty of Medicine The University of Tokyo Department of Lifetime Oral Health Care Science Graduate School of Medical and Dental SciencesTokyo Medical and Dental University Department of Periodontology Graduate School of Medical and Dental Sciences Tokyo Medical and Dental University Department of Immunoparasitology Research Institute for Microbial Diseases Osaka University

Clinical studies have shown that Aggregatibacter actinomycetemcomitans(A. actinomycetemcomitans) is associated with aggressive periodontitis and can potentially trigger or exacerbate rheumatoid arthritis(RA). However, the mechanism is poorly ***, we show that systemic infection with A. actinomycetemcomitans triggers the progression of arthritis in mice anti-collagen antibody-induced arthritis(CAIA) model following IL-1β secretion and cell infiltration in paws in a manner that is dependent on caspase-11-mediated inflammasome activation in macrophages. The administration of polymyxin B(PMB), chloroquine, and antiCD11b antibody suppressed inflammasome activation in macrophages and arthritis in mice, suggesting that the recognition of lipopolysaccharide(LPS) in the cytosol after bacterial degradation by lysosomes and invasion via CD11b are needed to trigger arthritis following inflammasome activation in macrophages. These data reveal that the inhibition of caspase-11-mediated inflammasome activation potentiates aggravation of RA induced by infection with A. actinomycetemcomitans. This work highlights how RA can be progressed by inflammasome activation as a result of periodontitis-associated bacterial infection and discusses the mechanism of inflammasome activation in response to infection with A. actinomycetemcomitans.

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Floristic Diversity, Stand Structure and Plant Life Traits in the Forest-Savanna Mosaic at Ndjole (Centre Cameroon)

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Open journal of Ecology 2024年第4期14卷 309-330页

作者： Djeuguen Vanessa Tchaleu Solefack marie Caroline Momo Mateso Aimé Kambale Ndondjeu Charles Tafen Yanick Borel Kamga Victor François Nguetsop Research Unit of Applied Botany (URBOA) Department of Plant Biology Faculty of Science University of Dschang Dschang Cameroon

With the aim of assessing floristic diversity, stand structure and vegetation ecology, the present work was carried out in the savanna mosaic forest of the locality of Ndjole (Centre Cameroon). A total of 30 floristic plots of 40 m × 40 m (1600 m2) were delineated in the different ecosystems (forest, forest-savanna contact zone and the savanna). Within each plot, all individuals with a diameter at breast height ≥ 10 cm at 1.30 m were taken into account. ANOVA was used to compare the means of the diversity indices of the different ecosystems, and the DUNCAN test at 5% significance level (XLSTAT 2016) to separate these means. A total of 85 species belonging to 67 genera and 33 families were recorded. That is, 68 species in semi-caducifolia forest, 45 in forest-savanna contact zone and 18 in savanna. Urticaceae, Combretaceae, Apocynaceae, Myristicaceae and Euphorbiaceae are the most diverse families in the forest. On the other hand, in contact zones, the Euphorbiaceae, Fabaceae, Annonaceae and Moraceae families are the most diversified, while in the savannas, the Combretaceae, Fabaceae and Annonaceae families are the most diversified. Shannon’s diversity index values (1.7 to 2.37 bits) reflect low specific diversity;Piélou’s equitability (0.86 to 0.9) shows good distribution of individuals within species. The diametric structure of woody species shows an inverted “j” shape in all plant communities. This indicates a high regeneration potential characterized by a greater number of small trees than large trees. Mesophanerophytes and megaphanerophytes are dominant in forests and forest-savanna contact zones, and microphanerophytes in the savannas. Endozoochory is the main mode of diaspore dissemination. As regards the distribution of phytogeographical types, it shows the overall dominance of Guineo-Congolese species in all plant communities. Our study provides detailed data on forest-savanna floristic and plant life traits in the mosaic and recommends further st

关键词： Mosaic Communities Dissemination Regeneration Diversity

An Improved jellyfish Algorithm for Multilevel Thresholding of Magnetic Resonance Brain Image Segmentations

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Computers, Materials & Continua 2021年第9期68卷 2961-2977页

作者： Mohamed Abdel-basset Reda Mohamed Mohamed Abouhawwash Ripon K.Chakrabortty Michael j.Ryan Yunyoung Nam Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA Capability Systems Centre School of Engineering and ITUNSW CanberraAustralia Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea

Image segmentation is vital when analyzing medical images,especially magnetic resonance(MR)images of the ***,several image segmentation techniques based on multilevel thresholding have been proposed for medical image segmentation;however,the algorithms become trapped in local minima and have low convergence speeds,particularly as the number of threshold levels ***,in this paper,we develop a new multilevel thresholding image segmentation technique based on the jellyfish search algorithm(jSA)(an optimizer).We modify the jSA to prevent descents into local minima,and we accelerate convergence toward optimal *** improvement is achieved by applying two novel strategies:Rankingbased updating and an adaptive ***-based updating is used to replace undesirable solutions with other solutions generated by a novel updating scheme that improves the qualities of the removed *** develop a new adaptive strategy to exploit the ability of the jSA to find a best-so-far solution;we allow a small amount of exploration to avoid descents into local *** two strategies are integrated with the jSA to produce an improved jSA(IjSA)that optimally thresholds brain MR *** compare the performances of the IjSA and jSA,seven brain MR images were segmented at threshold levels of 3,4,5,6,7,8,10,15,20,25,and *** was compared with several other recent image segmentation algorithms,including the improved and standard marine predator algorithms,the modified salp and standard salp swarm algorithms,the equilibrium optimizer,and the standard jSA in terms of fitness,the Structured Similarity Index Metric(SSIM),the peak signal-to-noise ratio(PSNR),the standard deviation(SD),and the Features Similarity Index Metric(FSIM).The experimental outcomes and the Wilcoxon rank-sum test demonstrate the superiority of the proposed algorithm in terms of the FSIM,the PSNR,the objective values,and the SD;in terms of the SSIM,IjSA was competitive with

关键词： Magnetic resonance imaging brain image segmentation artificial jellyfish search algorithm ranking method local minima Otsu method

沸石表面有机金属化学──ZSM-5外表面上—Ge(n-C_4H_9)_x基团的接枝及其性质研究

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高等学校化学学报 2001年第2期22卷 285-288页

作者：王绪绪赵慧霞付贤智 Frédéric LEFEBVRE j.an-marie basset 福州大学光催化研究所福州350002 Laboratoire de Chimie Organo métalliquede Surface

用气体分析及IR ,NMR和元素分析等方法研究了真空系统中 2 30和 2 80℃下四丁基锗在ZSM 5沸石表面上的接枝反应 ,并对所得沸石的热稳定性和吸附性质进行了表征 .与作者曾报道的在硅胶及丝光沸石上的反应类似 ,四丁基锗也能与ZSM 5沸石... 详细信息

用气体分析及IR ,NMR和元素分析等方法研究了真空系统中 2 30和 2 80℃下四丁基锗在ZSM 5沸石表面上的接枝反应 ,并对所得沸石的热稳定性和吸附性质进行了表征 .与作者曾报道的在硅胶及丝光沸石上的反应类似 ,四丁基锗也能与ZSM 5沸石表面上的硅羟基发生缩合反应 ,在其外表面或孔口生成组成为 (≡Si—O) xGe(n C4 H9) 4-x(x =13)的表面有机锗化合物 .在 2 30℃接枝丁基锗基团不影响沸石的结构和表面积 ,仅改变它的孔口大小 .在改性后的沸石上 ,N2 的吸附性质没有改变 ,而不同分子尺寸的烃 ,如正己烷、2 甲基戊烷、2 ,3 二甲基丁烷却呈现出完全不同于起始ZSM 5沸石的择形吸附效应 .

关键词： ZSM-5 四丁基锗表面修饰有机金属化合物表面接枝反应沸石

Medical Feature Selection Approach Based on Generalized Normal Distribution Algorithm

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Computers, Materials & Continua 2021年第12期69卷 2883-2901页

作者： Mohamed Abdel-basset Reda Mohamed Ripon K.Chakrabortty Michael j.Ryan Yunyoung Nam Mohamed Abouhawwash Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Capability Systems Centre School of Engineering and ITUNSWCanberraAustralia Department of Computer Science and Engineering Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA

This paper proposes a new pre-processing technique to separate the most effective features from those that might deteriorate the performance of the machine learning classifiers in terms of computational costs and classification accuracy because of their irrelevance,redundancy,or less information;this pre-processing process is often known as feature *** technique is based on adopting a new optimization algorithm known as generalized normal distribution optimization(GNDO)supported by the conversion of the normal distribution to a binary one using the arctangent transfer function to convert the continuous values into binary ***,a novel restarting strategy(RS)is proposed to preserve the diversity among the solutions within the population by identifying the solutions that exceed a specific distance from the best-so-far and replace them with the others created using an effective updating *** strategy is integrated with GNDO to propose another binary variant having a high ability to preserve the diversity of the solutions for avoiding becoming stuck in local minima and accelerating convergence,namely improved GNDO(IGNDO).The proposed GNDO and IGNDO algorithms are extensively compared with seven state-of-the-art algorithms to verify their performance on thirteen medical instances taken from the UCI *** is shown to be superior in terms of fitness value and classification accuracy and competitive with the others in terms of the selected *** the principal goal in solving the FS problem is to find the appropriate subset of features that maximize classification accuracy,IGNDO is considered the best.

关键词： Generalized normal distribution optimization feature selection transfer function novel restarting strategy UCI repository