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arXiv 2018年

作者： Dai, Siyuan Tymchenko, Mykhailo Xu, Zai-Quan Tran, Toan T. Yang, Yafang Ma, Qiong Watanabe, Kenji Taniguchi, Takashi Jarillo-Herrero, Pablo Aharonovich, Igor Basov, Dimitri N. Tao, Tiger H. Alù, Andrea Department of Electrical & Computer Engineering University of Texas AustinTX78712 United States Institute of Biomedical Materials and Devices Faculty of Science University of Technology Sydney UltimoNSW2007 Australia Department of Physics Massachusetts Institute of Technology CambridgeMA02215 United States National Institute for Materials Science Namiki 1-1 Tsukuba Ibaraki305-0044 Japan Department of Physics Columbia University New YorkNY10027 United States Department of Mechanical Engineering University of Texas AustinTX78712 United States Photonics Initiative Advanced Science Research Center City University of New York New York10031 United States Physics Program Graduate Center City University of New York New York10016 United States Department of Electrical Engineering City College of the City University of New York New York10031 United States

Imaging materials and inner structures with resolution below the diffraction limit has become of fundamental importance in recent years for a wide variety of applications. In this work, we report sub-diffractive internal structure diagnosis of hexagonal boron nitride by exciting and imaging hyperbolic phonon polaritons. Based on their unique propagation properties, we are able to accurately locate defects in the crystal interior with nanometer resolution. The precise location, size and geometry of the concealed defects is reconstructed by analyzing the polariton wavelength, reflection coefficient and their dispersion. We have also studied the evolution of polariton reflection, transmission and scattering as a function of defect size and photon frequency. The nondestructive high-precision polaritonic structure diagnosis technique introduced here can be also applied to other hyperbolic or waveguide systems, and may be deployed in the next-generation bio-medical imaging, sensing and fine structure analysis. Copyright © 2018, The Authors. All rights reserved.

关键词： Van der Waals forces

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Dark Excitons: Dark-Exciton-Mediated Fano Resonance from a Single Gold Nanostructure on Monolayer WS2at Room Temperature (Small 31/2019)

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Small 2019年第31期15卷

作者： Mingsong Wang Zilong Wu Alex Krasnok Tianyi Zhang Mingzu Liu He Liu Leonardo Scarabelli Jie Fang Luis M. Liz-Marzán Mauricio Terrones Andrea Alù Yuebing Zheng Department of Mechanical Engineering Texas Materials Institute The University of Texas at Austin Austin TX 78712 USA Photonics Initiative Advanced Science Research Center Physics Program Graduate Center Department of Electrical Engineering City College of the City University of New York New York NY 10031 USA Department of Materials Science and Engineering Department of Physics Department of Chemistry Center for 2-Dimensional and Layered Materials The Pennsylvania State University University Park PA 16802 USA Department of Chemistry and Biochemistry California NanoSystems Institute University of California Los Angeles Los Angeles CA 90095 USA Bionanoplasmonics Laboratory CIC biomaGUNE Paseo de Miramón 182 20014 Donostia-San Sebastián Spain Ikerbasque Basque Foundation for Science 48013 Bilbao Spain Biomedical Research Networking Center in Bioengineering Biomaterials and Nanomedicine CIBER-BBN 20014 Donostia-San Sebastián Spain

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Chemical Composition,Antioxidant and Antimicrobial Activity of the Oil and Plant Extract Myrocarpus frondosus Allemao

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American Journal of Plant sciences 2017年第7期8卷 1560-1571页

作者： Ivandra Ignês de Santi Darci Alberto Gatto Miriam Ribeiro Galvao Machado Patrícia Soares Bilhalva dos Santos Rogerio Ant?nio Freitag Natural Products Research Laboratory Graduate Program in Biochemistry and Bioprospecting Federal University of Pelotas Pelotas Brasil Postgraduate Program Materials Science and Engineering Federal University of Pelotas Pelotas Brasil Center for Chemical Sciences Pharmaceutical and Food Federal University of Pelotas Pelotas Brasil Chemical and Environmental Engineering Department University of the Basque Country (UPV/EHU) San Sebastian Spain

The objective of this study was to evaluate the chemical profile of extracts (aqueous and ethanol) and the essential oil of Myrocarpus frondosus Allem?o, the sensitivity of strains of Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Listéria monocytogenes, front the extracts and essential oil, by means of the microdilution method in broth, the antioxidant activity by the ABTS method, and the content of phenolic compounds present in the extracts and oil. For the preparation of extracts from plant leaves used with ethanol and water, then separated, the chemical identification of compounds was performed by high-performance liquid chromatography (CLAE-DAD) and gas chromatography coupled to mass spectrum (CG/MS). With the chemical analysis of the extracts obtained the presence of the major compound rutin, and oil major compound was found germacrene B. In the microdilution method in broth, oil and extracts showed inhibition against all the bacteria tested in the concentrations 1 mg/ml to 0.25 mg/ml, except for Staphylococcus aureus at a concentration of 0.25 mg/ml of the essential oil and trans-caryophyllene. The results of Minimum Bactericidal Concentration showed that the essential oil had bactericidal activity at a concentration of 1mg/ml for all bacteria tested and trans-caryophyllene at the same concentration only for Listeria monocytogenes. In relation to the essential oil, antioxidant activity showed higher radical reduction capacity of 40.92% and the content of phenolic compounds ethanol extract showed more 12.72%. The in vitro results support the conclusion that the essential oil is very promising both in antimicrobial action as antioxidant activity and the leaf extracts on antioxidant activity.

关键词： Myrocarpus frondosus Allemao Antimicrobial Antioxidant

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Void distributions reveal structural link between jammed packings and protein cores

arXiv

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arXiv 2018年

作者： Treado, John D. Mei, Zhe Regan, Lynne O'Hern, Corey S. Department of Mechanical Engineering & Materials Science Yale University New HavenCT06520 United States Integrated Graduate Program in Physical & Engineering Biology Yale University New HavenCT06520 United States Department of Chemistry Yale University New HavenCT06520 United States Department of Molecular Biophysics & Biochemistry Yale University New HavenCT06520 United States Department of Physics Yale University New HavenCT06520 United States Department of Applied Physics Yale University New HavenCT06520 United States Program in Computational Biology and Bioinformatics Yale University New HavenCT06520 United States

Dense packing of hydrophobic residues in the cores of globular proteins determines their stability. Recently, we have shown that protein cores possess packing fraction φ ≈ 0.56, which is the same as dense, random packing of amino acid-shaped particles. In this article, we compare the structural properties of protein cores and jammed packings of amino acid-shaped particles in much greater depth by measuring their local and connected void regions. We find that the distributions of surface Voronoi cell volumes and local porosities obey similar statistics in both systems. We also measure the probability that accessible, connected void regions percolate as a function of the size of a spherical probe particle and show that both systems possess the same critical probe size. By measuring the critical exponent τ that characterizes the size distribution of connected void clusters at the onset of percolation, we show that void percolation in packings of amino acid-shaped particles and protein cores belong to the same universality class, which is different from that for void percolation in jammed sphere packings. We propose that the connected void regions of proteins are a defining feature of proteins and can be used to differentiate experimentally observed proteins from decoy structures that are generated using computational protein design software. This work emphasizes that jammed packings of amino acid-shaped particles can serve as structural and mechanical analogs of protein cores, and could therefore be useful in modeling the response of protein cores to cavity-expanding and -reducing mutations. Copyright © 2018, The Authors. All rights reserved.

关键词： Amino acids

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Nanophotonic engineering of far-field thermal emitters

arXiv

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arXiv 2018年

作者： Baranov, Denis G. Xiao, Yuzhe Nechepurenko, Igor A. Krasnok, Alex Alù, Andrea Kats, Mikhail A. Department of Physics Chalmers University of Technology Gothenburg412 96 Sweden Department of Electrical and Computer Engineering University of Wisconsin-Madison WI United States Dukhov Research Institute of Automatics 22 Sushchevskaya Moscow127055 Russia Photonics Initiative Advanced Science Research Center City University of New York NY10031 United States Physics Program Graduate Center City University of New York NY10016 United States Department of Electrical Engineering City College of The City University of New York New York10031 United States Department of Materials Science and Engineering University of Wisconsin-Madison WI United States Department of Physics University of Wisconsin-Madison WI United States

Thermal emission is a ubiquitous and fundamental process by which all objects at non-zero temperatures radiate electromagnetic energy. This process is often presented to be incoherent in both space and time, resulting in broadband, omnidirectional light emission toward the far field, with a spectral density related to the emitter temperature by Planck’s law. Over the past two decades, there has been considerable progress in engineering the spectrum, directionality, polarization, and temporal response of thermally emitted light using nanostructured materials. This review summarizes the basic physics of thermal emission, lays out various nanophotonic approaches to engineer thermal-emission in the far field, and highlights several relevant applications, including energy harvesting, lighting, and radiative cooling. Copyright © 2018, The Authors. All rights reserved.

关键词： Spectral density

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2D Transition Metal Dichalcogenide: Unraveling High-Yield Phase-Transition Dynamics in Transition Metal Dichalcogenides on Metallic Substrates (Adv. Sci. 7/2019)

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Advanced science 2019年第7期6卷 1970042-1970042页

作者： Xinmao Yin Chi Sin Tang Di Wu Weilong Kong Changjian Li Qixing Wang Liang Cao Ming Yang Yung-Huang Chang Dianyu Qi Fangping Ouyang Stephen J. Pennycook Yuan Ping Feng Mark B. H. Breese Shi Jie Wang Wenjing Zhang Andrivo Rusydi Andrew T. S. Wee Department of Physics Faculty of Science National University of Singapore Singapore 117542 Singapore Singapore Synchrotron Light Source (SSLS) National University of Singapore Singapore 117603 Singapore NUS Graduate School for Integrative Sciences and Engineering National University of Singapore Singapore 117456 Singapore International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology Shenzhen University Shenzhen 518060 China Hunan Key Laboratory of Super-microstructure and Ultrafast Process School of Physics and Electronics Central South University No. 932 South Lushan Road Changsha Hunan Province 410083 China Department of Materials Science and Engineering National University of Singapore 9 Engineering Drive 1 Singapore 117575 Singapore Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field Laboratory of the Chinese Academy of Sciences Hefei 230031 China Institute of Materials Research and Engineering A∗STAR (Agency for Science Technology and Research) 2 Fusionopolis Way Singapore 138634 Singapore Bachelor Program in Interdisciplinary Studies National Yunlin University of Science and Technology Yunlin 640 Taiwan

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Lithium‐Ion Batteries: Cooling Induced Surface Reconstruction during Synthesis of High‐Ni Layered Oxides (Adv. Energy Mater. 43/2019)

引用

Advanced Energy materials 2019年第43期9卷

作者： Ming‐Jian Zhang Xiaobing Hu Maofan Li Yandong Duan Luyi Yang Chong Yin Mingyuan Ge Xianghui Xiao Wah‐Keat Lee Jun Young Peter Ko Khalil Amine Zonghai Chen Yimei Zhu Eric Dooryhee Jianming Bai Feng Pan Feng Wang School of Advanced Materials Peking University Shenzhen Graduate School Shenzhen 518055 P. R. China Sustainable Energy Technologies Department Brookhaven National Laboratory Upton NY 11973 USA Condensed Matter Physics and Materials Science Department Brookhaven National Laboratory Upton NY 11973 USA School of Science Hebei University of Science and Technology Shijiazhuang 050018 P. R. China Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo 315201 P. R. China National Synchrotron Light Source II Brookhaven National Laboratory Upton NY 11973 USA The Cornell High Energy Synchrotron Source Cornell University Ithaca NY 14853 USA Electrochemical Technology Program Chemical Sciences and Engineering Division Argonne National Laboratory 9700 South Cass Avenue Lemont IL 60439 USA Materials Science and Engineering Stanford University Stanford CA 94305 USA Institute for Research and Medical Consultations (IRMC) Imam Abdulrahman Bin Faisal University (IAU) Dammam 34212 Saudi Arabia

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Spatially separated self-assembled silver dendrites for highly sensitive SERS applications

arXiv

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arXiv 2018年

作者： Yakimchuk, D.V. Kaniukov, E.Y. Lepeshov, S.I. Bundyukova, V.D. Demyanov, S.E. Arzumanyan, G.M. Doroshkevich, N.V. Mamatkulov, K.Z. Alù, A. Bochmann, A. Presselt, M. Stranik, O. Krasnok, A. Sivakov, V. Scientific-Practical Materials Research Center NAS of Belarus Minsk ITMO University St. Petersburg Russian Federation Joint Institute for Nuclear Research Dubna Russian Federation Dubna State University Dubna Russian Federation Photonics Initiative Advanced Science Research Center Physics Program Graduate Center City University of New York Department of Electrical Engineering City College of New York United States Ernst-Abbe-Hochschule Jena Jena Germany Leibniz Institute of Photonic Technology Jena Germany

Even after more than four decades of rapid-pace advances, the adoption of Surface-Enhanced Raman Scattering (SERS) remains limited, due to the difficulties in fabrication of effective and affordable nanostructured surfaces or templates. From this point-of-view, self-assembly techniques of SERS substrates formation allowing fabrication of highly branched dendritic silver nanostructures, which are very promising for biosensor applications. However, these techniques suffer from the lack of control over the resulting structures. Herein, we propose an electroless wetchemical approach for highly reproducible fabrication of spatially separated plasmonic active silver dendrites in a porous matrix of Si/SiO2 template via controlled self-assembly of silver in a limited volume. The proposed approach allows fabrication of spatially separated silver dendrites with sub-10-nm gaps between neighboring branches, which possessing strong electric field enhancement ina wide spectral range. The fabricated silver dendritic structures enable a SERS enhancement factor of ∼108and the analyte detection limit of ∼10-15M, which is at the level of single molecule sensitivity. The comparison of simulation results with SERS experiments allows to distinguish the presence of electromagnetic and chemical contributions, which have a different effect at various analyte concentrations. Copyright © 2018, The Authors. All rights reserved.

关键词： Fabrication

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Probing the interaction of noble gases with pristine and nitrogen-doped graphene through Raman spectroscopy

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Physical Review B 2018年第19期97卷 195419-195419页

作者： Renato Cunha Néstor Perea-López Ana Laura Elías Kazunori Fujisawa Victor Carozo Simin Feng Ruitao Lv Maria Cristina dos Santos Mauricio Terrones Paulo T. Araujo Department of Physics The Pennsylvania State University University Park Pennsylvania 16802 USA Center for 2-Dimensional and Layered Materials The Pennsylvania State University University Park Pennsylvania 16802 USA Faculdade de Ciências Exatas e Naturais Universidade Federal do Pará Campus Universitário de Tocantins PA 68.400-000 Brazil Department of Physics Pontifical Catholic University of Rio de Janeiro Rio de Janeiro RJ 22451900 Brazil Key Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University Beijing 100084 People's Republic of China Zernike Institute for Advanced Materials University of Groningen Nijenborgh 4 Groningen 9747 AG The Netherlands Department of Chemistry The Pennsylvania State University University Park Pennsylvania 16802 USA Institute of Carbon Science and Technology Shinshu University 4-17-1 Wakasato Nagano-city 380–8553 Japan Department of Physics and Astronomy The University of Alabama Tuscaloosa Alabama 35487 USA Center for Information Technology (MINT) The University of Alabama Alabama 35487 USA Natural Sciences Institute Graduate Program in Physics – Federal University of Para Belem PA 66075-110 Brazil

The interactions of adsorbates with graphene have received increasing attention due to its importance in the development of applications involving graphene-based coatings. Here, we present a study of the adsorption of noble gases on pristine and nitrogen-doped graphene. Single-layer graphene samples were synthesized by chemical vapor deposition (CVD) and transferred to transmission electron microscopy (TEM) grids. Several noble gases were allowed to adsorb on the suspended graphene substrate at very low temperatures. Raman spectra show distinct frequency blue shifts in both the 2D and G bands, which are induced by gas adsorption onto high quality single layer graphene (1LG). These shifts, which we associate with compressive biaxial strain in the graphene layers induced by the noble gases, are negligible for nitrogen-doped graphene. Additionally, a thermal depinning transition, which is related to the desorption of a noble gas layer from the graphene surface at low temperatures (ranging from 20 to 35 K), was also observed at different transition temperatures for different noble gases. These transition temperatures were found to be 25 K for argon and 35 K for xenon. Moreover, we were able to obtain values for the compressive biaxial strain in graphene induced by the adsorbed layer of noble gases, using Raman spectroscopy. Ab initio calculations confirmed the correlation between the noble gas-induced strain and the changes in the Raman features observed.

关键词： Adsorption Physisorption Surface & interfacial phenomena Graphene Density functional theory High-resolution transmission electron microscopy Raman spectroscopy

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Body appreciation around the world: Measurement invariance of the Body Appreciation Scale-2 (BAS-2) across 65 nations, 40 languages, gender identities, and age

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Body image 2023年 46卷 449-466页

作者： Viren Swami Ulrich S Tran Stefan Stieger Toivo Aavik Hamed Abdollahpour Ranjbar Sulaiman Olanrewaju Adebayo Reza Afhami Oli Ahmed Annie Aimé Marwan Akel Hussam Al Halbusi George Alexias Khawla F Ali Nursel Alp-Dal Anas B Alsalhani Sara Álvares-Solas Ana Carolina Soares Amaral Sonny Andrianto Trefor Aspden Marios Argyrides John Jamir Benzon R Aruta Stephen Atkin Olusola Ayandele Migle Baceviciene Radvan Bahbouh Andrea Ballesio David Barron Ashleigh Bellard Sóley Sesselja Bender Kerime Derya Beydağ Gorana Birovljević Marie-Ève Blackburn Teresita Borja-Alvarez Joanna Borowiec Miroslava Bozogáňová Solfrid Bratland-Sanda Matthew H E M Browning Anna Brytek-Matera Marina Burakova Yeliz Çakır-Koçak Pablo Camacho Vittorio Emanuele Camilleri Valentina Cazzato Silvia Cerea Apitchaya Chaiwutikornwanich Trawin Chaleeraktrakoon Tim Chambers Qing-Wei Chen Xin Chen Chin-Lung Chien Phatthanakit Chobthamkit Bovornpot Choompunuch Emilio J Compte Jennifer Corrigan Getrude Cosmas Richard G Cowden Kamila Czepczor-Bernat Marcin Czub Wanderson Roberto da Silva Mahboubeh Dadfar Simon E Dalley Lionel Dany Jesus Alfonso D Datu Pedro Henrique Berbert de Carvalho Gabriel Lins de Holanda Coelho Avila Odia S De Jesus Sonia Harzallah Debbabi Sandesh Dhakal Francesca Di Bernardo Donka D Dimitrova Jacinthe Dion Barnaby Dixson Stacey M Donofrio Marius Drysch Hongfei Du Angel M Dzhambov Claire El-Jor Violeta Enea Mehmet Eskin Farinaz Farbod Lorleen Farrugia Leonie Fian Maryanne L Fisher Michał Folwarczny David A Frederick Matthew Fuller-Tyszkiewicz Adrian Furnham Antonio Alías García Shulamit Geller Marta Ghisi Alireza Ghorbani Maria Angeles Gomez Martinez Sarah Gradidge Sylvie Graf Caterina Grano Gyöngyvér Gyene Souheil Hallit Motasem Hamdan Jonathan E Handelzalts Paul H P Hanel Steven R Hawks Issa Hekmati Mai Helmy Tetiana Hill Farah Hina Geraldine Holenweger Martina Hřebíčková Olasupo Augustine Ijabadeniyi Asma Imam Başak İnce Natalia Irrazabal Rasa Jankauskiene Ding-Yu Jiang Micaela Jiménez-Borja Verónica Jiménez-Borja Evan M Johnson Veljko Jov School of Psychology and Sport Science Anglia Ruskin University Cambridge United Kingdom Centre for Psychological Medicine Perdana University Kuala Lumpur Malaysia. Electronic address: viren.swami@aru.ac.uk. Department of Cognition Emotion and Methods in Psychology Faculty of Psychology University of Vienna Vienna Austria. Department of Psychology and Psychodynamics Karl Landsteiner University of Health Sciences Krems an der Donau Austria. Institute of Psychology University of Tartu Tartu Estonia. Department of Psychology Koç University Istanbul Turkiye. Department of Psychology and Behavioural Studies Ekiti State University Ado-Ekiti Nigeria. Department of Art Studies Tarbiat Modares University Tehran Iran. Department of Psychology University of Chittagong Chattogram Bangladesh. Department of Psychoeducation and Psychology Université du Québec en Outaouais Saint-Jérôme Canada. INSPECT-LB: National Institute of Public Health Clinical Epidemiology and Toxicology Beirut Lebanon School of Pharmacy Lebanese International University Beirut Lebanon. Department of Management Ahmed Bin Mohammad Military College Doha Qatar. Faculty of Psychology Panteion University of Social and Political Sciences Athens Greece. Royal College of Surgeons Ireland-Bahrain Adliya Bahrain. Department of Midwifery Faculty of Health Sciences Munzur University Tunceli Turkiya. Department of Oral Medicine and Diagnostic Sciences Vision College of Dentistry and Nursing Vision Colleges Riyadh Saudi Arabia. Facultad de Ciencias de la Vida Universidad Regional Amazónica Ikiam Muyuna Ecuador. Federal Institute of Education Science and Technology of Southeast Minas Gerais Barbacena Brazil. Department of Psychology Universitas Islam Indonesia Yogyakarta Indonesia. Department of Psychology Aberystwyth University Ceredigion United Kingdom. Department of Psychology Neapolis University Pafos Paphos Cyprus. Department of Psychology De La Salle University Phillippines. Department of Gen

The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research.

关键词： Body appreciation Body appreciation Scale-2 (BAS-2) Cross-cultural Measurement invariance Multi-group confirmatory factor analysis (MG-CFA) Psychometrics Structural analysis

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