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Precision Measurement of Complex Optics Using a Scanning‑Point Multiwavelength Interferometer Operating in the Visible Domain

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Nanomanufacturing and Metrology 2023年第2期6卷 19-26页

作者： marc Wendel Ametek GmbH/BU Taylor Hobson Rudolf-Diesel-Str.1664331 WeiterstadtGermany

The growing demands of optical systems have led to increasingly complex aspheres and *** this paper,an established measurement system in asphere production,which is also a promising approach in high-precision freeform metrology,is *** is based on a scanning-point multiwavelength interferometer *** scanning principle enables great fexibility,reduces setup time and costs,and has almost no limitations in spherical *** to the absolute measurement capability,the utilized multiwavelength approach is benefcial for segmented,annular,and discrete surfaces,which are common designs of modern applications’optical *** metrology system enables measurements on a nanometer scale on a great variety of apertures—from 1 to 1000 ***,a new short-coherence multiwavelength interferometer operating in the visible domain has been *** enables the high-precision measurement on silicon-coated surfaces,which can be found in space applications and are also commonly used for extreme-ultraviolet(EUV)lithographic setups,which will be used as an example throughout this *** to the large absolute measurement capability,applied grating structures for suppressing infrared light in the EUV process can easily be *** paper summarizes the basic working principles of the proposed metrology system,explains the special requirements for diferent felds of application,highlights the capabilities of the visible multiwavelength approach,and shows the measurement results.

关键词： Multiwavelength interferometer Scanning-point sensor Metrology Short coherence interferometry

Phytochemical Analysis and Antimicrobial Activity of Lawsonia inermis Leaf Extracts from Burkina Faso

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American Journal of Plant Sciences 2024年第7期15卷 552-576页

作者： Ollo Youl Soumaïla Konaté Ernest N. Sombié Rainatou Boly Boukaré Kaboré Moumouni Koala Arouna Zoungrana Saybou Savadogo Christian marc Tahita Innocent Valea Halidou Tinto Adama Hilou Maminata Traoré-Coulibaly Laboratoire de Biochimie et de Chimie Applique (LABIOCA) Universit de Ouagadougou Ouagadougou Burkina Faso Agence Nationale Pour la Scurit Sanitaire de lEnvironnement de lAlimentation du Travail et des Produits de Sant (ANSSEAT) Ouagadougou Burkina Faso Laboratoire de Recherche-Dveloppement de Phytomdicaments et Mdicaments (L-RD/PM) Institut de Recherche en Sciences de la Sant (IRSS-CNRST) Ouagadougou Burkina Faso Laboratoire de Chimie Organique et de Physique Applique (LCOPA) cole Doctorale Sciences et Technologie Universit Joseph KI-ZERBO Ouagadougou Burkina Faso Laboratoire Sciences de la Vie et de la Terre (LASVT) cole Doctorale Sciences et Technologie Universit Norbert ZONGO Koudougou Burkina Faso Unit de Recherche Clinique de Nanoro Institut de Recherche en Sciences de la Sant (IRSS-CNRST) Nanoro Burkina Faso

Lawsonia inermis is a hairless plant growing in various regions of North Africa, the Indian subcontinent, and the Middle East. It possesses many medicinal attributes, including curative properties against infectious dermatoses. This study was carried out to evaluate the phytochemical profile of the crude ethanolic extract of the plant leaves and its fractions as well as their antimicrobial activities. The phytochemical profile was performed using high-performance thin-layer chromatography (HPTLC), gas chromatography-mass spectrometry (GC-MS), and high-performance liquid chromatography (HPLC). Additionally, the phenolic and flavonoid contents were determined using the Folin-Ciocalteu spectrophotometric and the aluminum trichloride methods. Antimicrobial activity was tested using disc diffusion and microdilution methods. The presence of flavonoids, tannins, sterols, and triterpenes was revealed. GC-MS detected twelve compounds main compounds consisting of saturated and unsaturated fatty acids and phenolic and terpenoid compounds among twenty-seven components. HPLC also detected high contents of phenolic acids and flavonoids. The most abundant triterpene and sterols were ursolic acid (around 43.14 g/100g DW, 13.9 g/100g dry weight (DW), and 0.68 g/100g DW) in the crude ethanolic extract of leaves (FeLi), hexane fraction (FHLi) and dichloromethane fraction (FDLi), respectively and, β-sitosterol in FeLi (56.7 mg/100g DW), FHLi (10.55 g/100g DW), FDLi (106.1 mg/100g DW) and butanol fraction (FBLi) (357.4 mg/100g DW). Among the flavonoids, rutin = 3.24 g/100g and quercetin = 0.63 g/100g in the ethanolic extract, rutin = 15.73 g/100g in the dichloromethane fraction, and rutin = 0.23 g/100g) in the aqueous fraction;and among phenolic compounds, caffeic acid (37.65 g/100g DW) and vanillic acid (22.70 g/100g DW) were the most important in the ethyl acetate fraction (FAeLi). All organic fractions exhibited interesting antibacterial and antifungal activities against the tested s

关键词： Lawsonia inermis Phytochemical Profile HPLC GC-MS Analysis Antimicrobial Activity

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追影人

中国国家天文 2024年第2期18卷 20-27页

作者：马克·布伊刘晗(译) 不详对外经济贸易大学英语学院北京外国语大学北京师范大学

通过业余望远镜观测者的通力合作,观测者们可以发现贯穿整个太阳系的小天体细节。你在用望远镜找什么呢?趣的东西吗?既然如此,不妨试试去寻找掩食吧。掩食是指一个天体从另一个天体前面经过,把后面那个天体挡住了。这个概念跟日食一样:... 详细信息

通过业余望远镜观测者的通力合作,观测者们可以发现贯穿整个太阳系的小天体细节。你在用望远镜找什么呢?趣的东西吗?既然如此,不妨试试去寻找掩食吧。掩食是指一个天体从另一个天体前面经过,把后面那个天体挡住了。这个概念跟日食一样:把我们的太阳换成遥远的恒星,把我们的月亮换成小行星或其他太阳系天体。

关键词：观测者日食小天体小行星望远镜太阳系天体恒星通力合作

An integrated hard- and soft-ware triboelectrochemical test rig for tribocorrosion experiments

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Friction 2015年第3期3卷 256-258页

作者： marc BELLANTONIO TRIBOtechnic 4 rue ValitonF-92110 ClichyFrance

Tribocorrosion is a degradation mechanism resulting from the interaction of mechanical(wear)and chemical(corrosion)*** interaction leads to surface damage that does not correspond to the simple sum of wear and corrosion taken *** tribocorrosion of material pairings thus requires the capability not only to control the mechanical and chemical test parameters but also to identify the relative contribution of corrosion and wear in the overall material *** paper describes a novel laboratory tribocorrosion test set-up combining in one experiment the control of mechanical input(load,velocity,and frequency)and output(friction and wear)parameters as well as the control of corrosion phenomena through a series of dedicated electrochemical methods(open circuit,potentiostatic and potentiodynamic measurements).The possibilities offered by this set-up are illustrated by selected case studies.

关键词： tribocorrosion friction and corrosion tribotechnic

Current Evidence and Diverse Perspectives on Attention-Deficit/Hyperactivity Disorder:A Systematic Review

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Journal of Psychological Research 2022年第2期4卷 1-10页

作者： Asrat genet Amnie Health Education Unit Education DepartmentEugenio María de Hostos Community College of The City University of New YorkBronxNY 10451the United States

Introduction:ADHD is one of the most common neurodevelopmental disorders in childhood and *** the disorder starts to manifest early in childhood,a significant proportion of cases often persists into *** negatively and significantly impacts social and occupational functioning and academic performance.A number of extant theories and scientific evidence provide insight into the genesis and manifestations of ADHD and the attendant challenges of significant dysfunction that individuals may encounter at home,school,and the ***:This systematic review was conducted through a literature search for published peer-reviewed articles using standard PRISMA *** goal of the study was to explore current theories,models,concepts,and risk factors about ADHD published in peer-reviewed *** made use of use several online databases-including PsycINFO,PubMed,Web of Science,ScienceDirect,and Medline in the process of searching for relevant *** peer-reviewed publications since the 1980s when the term Attention-Deficit/Hyperactivity Disorder(ADHD)was introduced in DSM-III-R were ***-peer-reviewed publications,including dissertations,editorials,commentaries,and materials published in languages other than English were *** and Discussion:The results of the review indicated that ADHD is characterized by a behavioral reaction that interferes with personal and social *** factors associated with ADHD fall into several major thematic areas,including genetic and hereditary factors;dietary and nutritional factors;parenting and behavioral factors;adverse early life events,and high-risk environmental factors,crystallized by a number of developmental and behavioral *** review also identified a number of extant models and theories that attempt to explain the diverse perspectives associated with ***:This study has attempted to identify the major risk factors and diverse models a

关键词： ADHD Developmental disorders Mental health Behavioral disorders

Congenital left ventricular aneurysms and diverticula： an entity in search of an identity

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Journal of Geriatric Cardiology 2017年第12期14卷 750-762页

作者： marc-Alexander Ohlow Heart Center Department of Cardiology Zentralklinik Bad Berka Germany

Congenital left ventricular aneurysm or diverticulum are rare cardiac malformations described in 809 cases since the first description in 1816, being associated with other cardiac, vascular or thoraco-abdominal abnormalities in about 70%. It appears to be a developmental anomaly, starting in the 4th embryonic week. In an experimental study, targeted knockdown of cardiac troponin T in the chick was performed at day 3, after the heart tube has formed. Morpholino treatment of gene TNNT2 at this stage led to the development of left ventricular diver- ticula （LVD） in the primitive left ventricular wall. Diagnosis of left ventricular aneurysms （LVA）/LVD can be made after exclusion of coro- nary artery disease, local or systemic inflammation or traumatic causes as well as cardiomyopathies. Clinically, most of LVA and LVD are asymptomatic or may cause systemic embolization, congestive heart failure, valvular regurgitation, ventricular wall rupture, ventricular tachycardia or sudden cardiac death. Diagnosis is established by imaging studies （echocardiography, magnetic resonance imaging or left ventricular angiography） visualizing the structural changes and accompanying abnormalities. Mode of treatment has to be individually tai- lored and depends on clinical presentation, accompanying abnormalities and possible complications, options include surgical resection （espe- cially in symptomatic patients）, anticoagulation after systemic embolization, radiofrequency ablation or implantation of an implantable car- dioverter defibrillator （ICD） in case of symptomatic ventricular tachycardias, and occasionally combined with class I- or III-antiarrhythmic drugs. Cardiac death occurs usually in childhood, is significantly more frequent in LVA patients and caused by congestive heart failure in most of the cases, whereas patients diagnosed with LVD died more frequently from rupture of the LVD.

关键词： Aneurysm Congenital Diverticulum Left ventricular Prognosis Therapy

布雷顿森林体系可为未来全球经济秩序奠定基础

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清华金融评论 2024年第8期 42-43页

作者：朱民马克·乌赞不详布雷顿森林体系委员会

当前世界面临不稳定性与诸多冲突,布雷顿森林体系可以为未来全球经济秩序奠定基础。布雷顿森林体系的目标是确保全球金融稳定、确保全球经济繁荣。在过去的数十年里,全球化一直是推动经济发展的重要动力,但当前出现了碎片化的情况。我... 详细信息

当前世界面临不稳定性与诸多冲突,布雷顿森林体系可以为未来全球经济秩序奠定基础。布雷顿森林体系的目标是确保全球金融稳定、确保全球经济繁荣。在过去的数十年里,全球化一直是推动经济发展的重要动力,但当前出现了碎片化的情况。我们需要将一个碎片化的全球经济重新组合在一起,推动未来世界变得更加公正、平等与包容。

关键词：布雷顿森林体系全球经济秩序推动经济发展全球金融不稳定性碎片化经济繁荣全球化

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冰岛东部最美小镇白日梦想家们的隐世仙境

环球人文地理 2024年第13期 144-153页

作者：邓文倩 Vladimir marieagns Nataliya Fotokon Sen Isabel Baldovi marc Jedamus Kristina Ryan Unsplash 摄图网

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉...

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉雅山脉……但实际上整部电影的取景地全都在冰岛。影片最令人印象深刻的部分，大概是沃尔特用公仔和小孩子交换滑板后，在一条盘山公路上急速滑行。公路的尽头就是被LonelyPlanet评为“冰岛东部最美小镇”的塞济斯菲厄泽。

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Global significance of oxygen and carbon isotope compositions of pedogenic carbonates since the Cretaceous

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Geoscience Frontiers 2021年第4期12卷 34-45页

作者： marc Jolivet Philippe Boulvais Géosciences Rennes CNRSUniv RennesUMR 6118F-35000RennesFrance

Few global syntheses of oxygen and carbon isotope composition of pedogenic carbonates have been attempted,unlike marine *** carbonates represent in-situ indicators of the climate conditions prevailing on *** δ^(18)O and δ^(13)C values of pedogenic carbonates are controlled by local and global factors,many of them not affecting the marine carbonates largely used to probe global climate *** compile pedogenic oxygen and carbon isotopic data(N=12,167)fromCretaceous to Quaternary-aged paleosols to identify potential trends through time and tie them to possible controlling *** discrete events such as the Paleocene-Eocene Thermal Maximum are clearly evidenced,our analysis reveals an increasing complexity in the distribution of the δ^(18)O vs δ^(13)C values through the *** could be expected,the rise of C4 plants induces a shift towards higherδ13C values during the Neogene and *** also show that the increase in global hypsometry during the Neogene plays a major role in controlling the δ^(18)O and δ^(13)C values of pedogenic carbonates by increasing aridity downwind of orographic ***,during the Quaternary,an increase of 3‰in δ^(18)O values is recorded both by the pedogenic carbonates and the marine foraminifera suggesting that both indicators may be used to track global climate signal.

关键词： Global isotopic signal Cretaceous–Quaternary Pedogenic carbonates Topography