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New ent-kaurene and germacrene derivatives from Mesona procumbens Hemseley and their biological activity

Natural Product Research 2023年第13期37卷 2172-2180页

作者： Ganzon, Jerome G. Liaw, Chia-Ching Lin, Yu-Chi Lin, Zhi-Hu Wang, Chang-Hung Chen, Che-Yi Chuang, Kuo-Hsiang Kuo, Yao-Haur Division of Chinese Materia Medica Development National Research Institute of Chinese Medicine Taipei Taiwan Department of Biochemical Science and Technology National Chiayi University Chiayi Taiwan Ph.D. Program in Clinical Drug Development of Herbal Medicine Taipei Medical University Taipei Taiwan Graduate Institute of Pharmacognosy College of Pharmacy Taipei Medical University Taipei Taiwan Graduate Institute of Integrated Medicine College of Chinese Medicine China Medical University Taichung Taiwan Department of Research and Development Starsci Biotech Co. Ltd Taoyuan Taiwan

Mesona procumbens Hemseley is a well-known traditional herbal medicine used for heat-related ailments. In Taiwan, boiled extracts of M. procumbens are also used as desserts called grass jelly. In this study, the hexane extract from 75% EtOH of M. procumbens showed potent activities on inhibition of E. coli β-glucuronidase (eβG) and NO production and cytotoxicity against MCF-7 and HepG2 cancer cell lines. Furthermore, using various flash columns and HPLC chromatography on the bioactive layer led to the isolation of twelve compounds (1–12), including a new ent-kaurene, mesokaurol A (1), and a new germacrene derivative, mesogermapene A (2). Their structures were elucidated by extensive spectroscopic analyses, especially 2 d NMR and mass data. Biological assays showed that compound 9 (linolenic acid) had specific activity on inhibition of eβG (68.27%) at 100 µg/mL but was non-inhibitory to human β-glucuronidase. Compound 1 possessed significant cytotoxicity against MCF-7 (EC₅₀ = 9.76 µM) and HepG2 (EC₅₀ = 8.64 µM) cancer cell lines. © 2022 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Anti-β-glucuronidase cytotoxicity germacrene Kaurane-type diterpene Mesona procumbens Hemseley

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design of Quantum dot Color Convertors for Inkjet-Printed Optoelectronic devices: Violet-Converted Full Color Mini-LEd

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Advanced Materials Technologies 2024年第3期9卷

作者： Lin, Chen-Te Zhuan, Yi-long Jung, Nian-Ting Hoang, Minh-Son Chen, Hsueh-Shih Ph.D. Program in Prospective Functional Materials Industry College of Engineering National Tsing Hua University Hsinchu30013 Taiwan Department of Materials Science and Engineering National Tsing Hua University Hsinchu30013 Taiwan College of Semiconductor Research National Tsing Hua University Hsinchu30013 Taiwan Department of Chemical Engineering & Materials Science College of Engineering Yuan Ze University Taoyuan32003 Taiwan

This study presents a strategy of design and development of inkjet-printable and UV-curable quantum dot (Qd) polymer-based inks and color conversion (CC) film for use in optoelectronic devices. At first, the preparation of a Qd ink is focused on two key aspects, that are Qd chemical compatibility and ink printability. In the hybrid organic–inorganic polymer/Qds system, it must be formulated to a well-dispersed ink, in which a dispersant additive without negative effect on Qds is introduced to enhance the Qd suspension. As the optical density of final dried Qd film is one of the most critical concerns in color conversion, Qd concentration should be as high as possible in the ink, which increases the ink viscosity. Consequently, a trade-off between Qd concentration and the ink viscosity associated with the ink-jetting temperature is considered to ensure the ink printability. Finally, the designed Qd ink is printed as color conversion film on a mini-LEd panel composed of two violet mini-chips to produce red and green emissions, while blue emission directly comes from a blue mini-chip. The final conversion efficiency of QdCC on mini-LEd panel are between 35% and 45%, showing the promising applications in optoelectronic devices. © 2023 Wiley-VCH GmbH.

关键词： Semiconductor quantum dots

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Web-based structural identifiability analyzer

arXiv

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arXiv 2021年

作者： Ilmer, Ilia Ovchinnikov, Alexey Pogudin, Gleb Ph.D. Program in Computer Science CUNY Graduate Center New York United States Department of Mathematics CUNY Queens College Ph.D. Programs in Mathematics and Computer Science CUNY Graduate Center New York United States LIX CNRS École Polytechnique Institute Polytechnique de Paris France

Parameter identifiability describes whether, for a given differential model, one can determine parameter values from model equations. Knowing global or local identifiability properties allows construction of better practical experiments to identify parameters from experimental data. In this work, we present a web-based software tool that allows to answer specific identifiability queries. Concretely, our toolbox can determine identifiability of individual parameters of the model and also provide all functions of parameters that are identifiable (also called identifiable combinations) from single or multiple experiments. The program is freely available at https://***/app/6509768948056064. © 2021, CC BY-SA.

关键词： Websites

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A Wavefront Shaping Approach to Second Harmonic Generation Enhancement in WS2

A Wavefront Shaping Approach to Second Harmonic Generation E...

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2024 Frontiers in Optics, FiO 2024

作者： Berger, Russell Mavian, Alex dimitrov, Edgar Zhang, Na Rumman, Nazifa Bassène, Pascal Terrones, Humberto Persans, Peter Terrones, Mauricio N'Gom, Moussa Department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute TroyNY12180 United States Department of Physics The Pennsylvania State University University ParkPA16802 United States Department of Electrical Computer and Systems Engineering RPI TroyNY United States Center for Ultrafast Optical Science University of Michigan Ann ArborMI48109-2102 United States The Shirley Ann Jackson Ph.D. Center for Biotechnology and Interdisciplinary Studies RPI TroyNY United States RPI 6015 Low Center TroyNY United States

Using feedback based wavefront shaping (WFS), we enhance the weak second harmonic (SH) generation up to 10x in Transition Metal dichalcogenide (TMd) crystals with nanometer scale interaction length probed by a femtose... 详细信息

关键词： Harmonic generation

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Enhanced removal of viral aerosols using nanosilver/TiO2-chitosan filters combined with a negative air ionizer

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Journal of Environmental Chemical Engineering 2024年第3期12卷

作者： dlamini, Wonder Nathi Yao, Ting-Ching Lee, Hsin-Jui Berekute, Abiyu Kerebo Sallah-Ud-din, Rasham Siregar, Sepridawati Yu, Kuo-Pin Institute of Environmental and Occupational Health Sciences National Yang-Ming Chiao-Tung University Taipei Taiwan Department of International Ph.D. Program in Environmental Sciences and Technology University System of Taiwan Taipei Taiwan Department of Chemistry College of Natural and Computational Sciences Arba Minch University Arbaminch Ethiopia Faculty of Mineral Technology AKPRIND Institute of Science & Technology Yogyakarta Indonesia

The presence of airborne viruses in bioaerosols is a significant and ongoing public health concern. In this context, this study aimed to develop a new filter that integrates nanosilver into a TiO2-chitosan matrix (nano-Ag/TiO2-CS) to inactivate the non-enveloped bacteriophage MS2 as a viral aerosol surrogate. The materials were characterized using various techniques, such as X-ray diffraction (XRd), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS). The SEM images showed that the nano-Ag particles were spheres with a high surface area for virus interactions and that the fiber surfaces were covered by nano-Ag, which enhanced contact with viruses. The optimal 5 wt% nano-Ag/TiO2-CS filter combined with a negative air ionizer (NAI) showed the highest viral aerosol removal efficiency, which reached 97 %. The use of an NAI during filtration enhanced the inactivation of the viral aerosols. A long-term antiviral efficacy assessment showed that the nano-Ag/TiO2-CS filter demonstrated robust durability, which is vital for real-world applications. The nanofilter proposed in this work is simple, safe, and cost-effective for inactivating viral aerosols to improve indoor air quality. © 2024 Elsevier Ltd

关键词： Aerosols

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Nanoscale Viscoelasticity Characterization of Engineered Organometallic Regenerative Tissue Scaffold Nanocomposites for Biomedical Applications

SSRN

引用

SSRN 2022年

作者： Yuya, philip A. Patel, Nimitt G. Department of Mechanical and Aerospace Engineering Clarkson University PotsdamNY13699 United States Materials Science and Engineering Ph.D. Program Clarkson University PotsdamNY13699 United States

This work is focused on nanoscale viscoelastic properties characterization of gold nanoparticles (AuNPs) reinforced chitosan nanocomposites using nanoindentation. Chitosan nanocomposite films reinforced with gold nanoparticles concentration (w/v) up to 0.25 mg/ml in chitosan were prepared via a solution evaporation technique. Creep and stress relaxation responses were modeled using the generalized Voigt model and the generalized Maxwell model, respectively. Nanoindentation experimental data were analyzed using these models to obtain model constants. Both displacement- and load-controlled ramp functions were used to indent the samples with a 100 µm conospherical indenter tip. The moduli increased with an increase in AuNPs concentration in chitosan. The plasticity index increased with an increase in AuNPs concentration indicating that the deformation became more plastic with an increase in the filler. The results also show the time-dependent viscous response of the nanocomposite is mainly governed by the response of the matrix because the characteristic time scales of the nanocomposite films are independent of the AuNPs concentration. © 2022, The Authors. All rights reserved.

关键词： Creep

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Interpretable classification of categorical time series using the spectral envelope and optimal scalings

The Journal of Machine Learning Research

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The Journal of Machine Learning Research 2022年第1期23卷 13513-13543页

作者： Zeda Li Scott A. Bruce Tian Cai Paul H. Chook Department of Information System and Statistics Baruch College The City University of New York New York NY Department of Statistics Texas A&M University College Station TX Ph.D. Program in Computer Science The Graduate Center The City University of New York New York NY

This article introduces a novel approach to the classification of categorical time series under the supervised learning paradigm. To construct meaningful features for categorical time series classification, we consider two relevant quantities: the spectral envelope and its corresponding set of optimal scalings. These quantities characterize oscillatory patterns in a categorical time series as the largest possible power at each frequency, or spectral envelope, obtained by assigning numerical values, or scalings, to categories that optimally emphasize oscillations at each frequency. Our procedure combines these two quantities to produce an interpretable and parsimonious feature-based classifier that can be used to accurately determine group membership for categorical time series. Classification consistency of the proposed method is investigated, and simulation studies are used to demonstrate accuracy in classifying categorical time series with various underlying group structures. Finally, we use the proposed method to explore key differences in oscillatory patterns of sleep stage time series for patients with different sleep disorders and accurately classify patients accordingly.

关键词： categorical time series classification optimal scaling multiple time series spectral envelope

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An Improvement of Three-Factor Remote User Authentication Protocol Using ECC

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International Journal of Network Security 2024年第3期26卷 528-534页

作者： Hwang, Min-Shiang Lin, Cheng-Ying Wu, Chia-Chun Department of Computer Science & Information Engineering Asia University Taichung Taiwan 500 Lioufeng Rd. Wufeng Taichung Taichung 41354 Taiwan Department of Medical Research China Medical University Hospital China Medical University Taiwan Ph.D. Program in Artificial Intelligence Asia University Taichung Taiwan 500 Lioufeng Rd. Wufeng Taichung Taichung 41354 Taiwan Kinmen892 Taiwan

With the development of the Internet, many patients’ private medical data are maliciously stolen by attackers. Therefore, Liu et al. proposed an improved ECC-based three-factor user authentication scheme. The main advantage of their scheme is that it provides the same or better security than other schemes using more secondary keys. However, this article will show that Liu et al.’s scheme is vulnerable to denial of service attacks. In addition, their protocol uses public key cryptography, which is inefficient. Finally, the method is not immune to counterfeit smart card attacks. In this paper, we also improve their protocol from the perspective of practicality and security. © (2024), (International Journal of Network Security). All rights reserved.

关键词： Authentication

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Multi-wavelength edge detection based on nonlocal multilayer GaAs–AlAs thin films

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Optics Letters 2025年第12期50卷 3856-3859页

作者： Sina Mohammadi Matthew Markowitz Francesco Monticone Mohammad Ali Miri Maria Tamargo Ph.D. Program in Physics The Graduate Center of the City University of New York New York New York 10016 USA Department of Physics Queens College of the City University of New York Queens New York 11367 USA School of Electrical and Computer Engineering Cornell University Ithaca New York 14853 USA Department of Chemistry The City College of New York New York New York 10031 USA

We demonstrate a compact multilayer GaAs–AlAs structure for passive optical edge detection at multiple wavelengths. Through the inverse design of the layer thicknesses, this structure manipulates spatial frequency components of an incoming wavefront, selectively reflecting high-frequency features while suppressing low-frequency intensity variations. Simulations reveal a reflectance transition from minimal to near-total as a function of numerical aperture, a property leveraged for enhancing edge contrast in optical imaging. For the first time, to our knowledge, we utilize molecular beam epitaxy (MBE) to fabricate edge detection devices, ensuring structural fidelity. Material characterization confirms high-quality interfaces, precise thickness control, and excellent uniformity, validating the suitability of MBE for this application. Experimental angle-resolved reflectance measurements closely align with theoretical predictions, demonstrating the feasibility of this approach for real-time, hardware-based optical image processing. The proposed design automatically works for at least two wavelengths and can be readily extended to operate at multiple wavelengths simultaneously. This work opens new possibilities for employing multilayer interference structures in high-performance optical imaging and real-time signal processing.

关键词： digital image processing Edge detection Inverse design Optical imaging Signal processing Thin films

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Synthesis of g-C3N4by doping Bi2S3for the photocatalytic degradation of NOxunder solar light

Synthesis of g-C3N4by doping Bi2S3for the photocatalytic deg...

引用

2021 International Symposium on Intelligent Signal Processing and Communication Systems, ISPACS 2021

作者： Hussain, Adnan Lin, Chitsan Cheng, Chih-Yu National Kaohsiung University of Science and Technology Ph.D. Program In College of Hydrosphere Kaohsiung Taiwan National Kaohsiung University of Science and Technology Department of Marine Environmental Engineering Kaohsiung Taiwan National Kaohsiung University of Science and Technology Department of Marine Biotechnology Kaohsiung Taiwan

ISBN: (纸本)9781665419512

NOx is a universal term for nitrogen oxide relevant to air pollution namely nitric oxide (NO) and nitrogen dioxide (N2). Mostly NOx is generated from the anthropogenic activities. Currently photo-catalysis is an emerging tool used for the reduction of air pollutants which helps to improve the air quality. In this experimental work Bi2S3 doped into g-C3N4 used as catalyst and the resulting products were characterized such as XRd, FTIR, EdS. Bi2S3@g-C3N4 can harvest the solar light due to narrow band gap which improve electron hole pair and generated hydroxyl and superoxide radicals. Furthermore, Bi2S3@g-C3N4 increased the photo-oxidation efficiency of the transformation from NOx to NO3. In short, this study provides accomplished and effective approach to prepare Bi2S3@g-C3N4 photocatalysts for NOx degradation under solar light. © 2021 IEEE.

关键词： Air quality

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