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Real-time generation of circular patterns in electron beam lithography

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NANOTECHNOLOGY AND PRECISION ENGINEERING 2024年第3期7卷 90-98页

作者： Li, Zhengjie Yin, Bohua Sun, Botong Huang, Jingyu Wang, Pengfei Han, Li chinese acad sci Inst Elect Engn Beijing 100190 Peoples R China Univ chinese acad sci Beijing 100190 Peoples R China

Electron beam lithography (EBL) involves the transfer of a pattern onto the surface of a substrate by first scanning a thin layer of organic film (called resist) on the surface by a tightly focused and precisely controlled electron beam (exposure) and then selectively removing the exposed or nonexposed regions of the resist in a solvent (developing). It is widely used for fabrication of integrated circuits, mask manufacturing, photoelectric device processing, and other fields. The key to drawing circular patterns by EBL is the graphics production and control. In an EBL system, an embedded processor calculates and generates the trajectory coordinates for movement of the electron beam, and outputs the corresponding voltage signal through a digital-to-analog converter (DAC) to control a deflector that changes the position of the electron beam. Through this procedure, it is possible to guarantee the accuracy and real-time control of electron beam scanning deflection. Existing EBL systems mostly use the method of polygonal approximation to expose circles. A circle is divided into several polygons, and the smaller the segmentation, the higher is the precision of the splicing circle. However, owing to the need to generate and scan each polygon separately, an increase in the number of segments will lead to a decrease in the overall lithography speed. In this paper, based on Bresenham's circle algorithm and exploiting the capabilities of a field-programmable gate array and DAC, an improved real-time circle-producing algorithm is designed for EBL. The algorithm can directly generate circular graphics coordinates such as those for a single circle, solid circle, solid ring, or concentric ring, and is able to effectively realizes deflection and scanning of the electron beam for circular graphics lithography. Compared with the polygonal approximation method, the improved algorithm exhibits improved precision and speed. At the same time, the point generation strategy is optimized

关键词： Electron beam lithography Circle production Micro-nano fabrication Pattern generator

Control of aluminum distribution in ZSM-5 zeolite for enhancement of its catalytic performance for propane aromatization

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FRONTIERS OF CHEMICAL sciENCE AND ENGINEERING 2024年第8期18卷 86-0页

作者： Ma, Zhao Shi, Dezhi Wang, Sen Dong, Mei Fan, Weibin chinese acad sci State Key Lab Coal Convers Inst Coal Chem Taiyuan 030001 Peoples R China Univ chinese acad sci Beijing 100049 Peoples R China

Regulation of aluminum distribution in zeolite framework is an effective method for improving its catalytic performance for propane aromatization. Herein, we found that recrystallization and post-realuminization of ZSM-5 cannot only create hollow structures to enhance the diffusion ability, but also adjust the content and position of paired aluminum species in its framework. Various characterizations results confirmed that increase of paired aluminum content and inducement of more aluminum atoms sited in the intersection cavity are beneficial to the formation of aromatic products in propane aromatization. As a result, the hollow-structured ZSM-5 zeolite with more paired aluminum (H-200-hollow) showed higher propane conversion and aromatics selectivity than other samples at the same conditions. The catalytic performance of H-200-hollow can be further improved by ion-exchanging with a small amount of Ga(III) species. The propane conversion and aromatics selectivity of Ga-200-hollow reached as high as 95% and 70%, respectively, at 540 degrees C and 1 atm.

关键词： propane aromatization zeolite aluminum distribution recrystallization and post-realuminization AL DISTRIBUTION REACTION PATHWAY ACID SITES FRAMEWORK METHANOL CONVERSION OLEFINS TEMPERATURE CRACKING STATE

World Federation of Acupuncture-Moxibustion Societies Clinical Practice Guideline on Acupuncture-Moxibustion: Non-Specific Low Back Pain recommendation summaries

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WORLD JOURNAL OF ACUPUNCTURE-MOXIBUSTION 2024年第3期34卷 213-221页

作者： Liu, Xiao-xu Guo, Ying-ying Fei, Yu-tong Huang, Man Ye, Yong-ming Yu, Jin-na Lin, Hui-ze Yan, Wen-xi Liu, Lan-ping Zhu, Ke-xin Liang, Jun Yang, Tao china acad chinese med sci Guanganmen Hosp Dept Acupuncture & Moxibust Beijing 100053 Peoples R China Beijing Univ chinese med Ctr Evidence Based Med Beijing 100029 Peoples R China china acad chinese med sci Guanganmen Hosp Beijing 100053 Peoples R China

Clinical Practice Guideline on Acupuncture and Moxibustion: Nonspecific low back pain was revised and released by the Standards Working Committee of World Federation of Acupuncture-Moxibustion Societies (WFAS) on October 9, 2023. This is the first clinical practice guideline (CPG) on acupuncture and moxibustion for nonspecific low back pain approved by an international academic organization, which provides the evidence-based recommendations and practical therapeutic protocols for international acupuncture practitioners. This CPG was developed by following Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology, and the Principles of the World Health Organization Handbook for Guideline Development . The guideline development group (GDG) from different countries, with different professions, played a critical role in the formulation of clinical questions, recommendations, and therapeutic protocols. Recommendations are the key content of a CPG and the direct answers to clinical questions. Hence, this article focuses on the recommendations of this CPG. The recommendations were formulated using the modified Delphi method and the GRADE grid rules, based on the updated systematic reviews of clinical evidence. A total of seven recommendations for ten clinical questions were formulated in this CPG, including one conditional recommendation for either the intervention or the comparison based on very low quality of evidence, and six conditional recommendations for the intervention based on very low quality of evidence. (c) 2024 World Journal of Acupuncture - Moxibustion House. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license ( http://***/licenses/by-nc-nd/4.0/ )

关键词： Nonspecific low back pain Acupuncture Moxibustion Clinical practice guideline Recommendations

Chasing Sequencing Perfection: Marching Toward Higher Accuracy and Lower Costs

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GENOMICS PROTEOMICS & BIOINFORMATICS 2024年第2期22卷 qzae024页

作者： Jia, Hangxing Tan, Shengjun Zhang, Yong E. chinese acad sci Inst Zool CAS Key Lab Zool Systemat & Evolut Beijing 100101 Peoples R China chinese acad sci Inst Zool State Key Lab Integrated Management Pest Insects & Beijing 100101 Peoples R China Univ chinese acad sci Beijing 100049 Peoples R China chinese acad sci CAS Ctr Excellence Anim Evolut & Genet Kunming 650223 Peoples R China

Next-generation sequencing (NGS), represented by Illumina platforms, has been an essential cornerstone of basic and applied research. However, the sequencing error rate of 1 per 1000 base pairs (10-3) represents a serious hurdle for research areas focusing on rare mutations, such as somatic mosaicism or microbe heterogeneity. By examining the high-fidelity sequencing methods developed in the past decade, we summarized three major factors underlying errors and the corresponding 12 strategies mitigating these errors. We then proposed a novel framework to classify 11 preexisting representative methods according to the corresponding combinatory strategies and identified 3 trends that emerged during methodological developments. We further extended this analysis to 8 long-read sequencing methods, emphasizing error reduction strategies. Finally, we suggest 2 promising future directions that could achieve comparable or even higher accuracy with lower costs in both NGS and long-read sequencing.

关键词： Sequencing error High-fidelity sequencing Consensus sequencing Single-molecule sequencing Rare mutation RARE MUTATIONS PARALLEL QUANTIFICATION ERRORS DAMAGE

An electrochemiluminescent magneto-immunosensor for ultrasensitive detection of hs-cTnI on a microfluidic chip

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NANOTECHNOLOGY AND PRECISION ENGINEERING 2024年第3期7卷 13-23页

作者： Hui, Yun Zhao, Zhen Shu, Weiliang Shen, Fengshan Kong, Weijun Geng, Shengyong Xu, Zhen Wu, Tianzhun Zhou, Wenhua Yu, Xuefeng chinese acad sci Shenzhen Inst Adv Technol Shenzhen Key Lab Micro Nano Biosensing Shenzhen 518055 Peoples R China chinese acad sci Biomed Imaging Sci & Syst Key Lab Shenzhen 518055 Peoples R China chinese acad sci Shenzhen Inst Adv Technol Shenzhen 518055 Peoples R China

Sensitive detection and precise quantitation of trace-level crucial biomarkers in a complex sample matrix has become an important area of research. For example, the detection of high-sensitivity cardiac troponin I (hs-cTnI) is strongly recommended in clinical guidelines for early diagnosis of acute myocardial infarction. Based on the use of an electrode modified by single-walled carbon nanotubes (SWCNTs) and a Ru(bpy)(3)(2+)-doped silica nanoparticle (Ru@SiO2)/tripropylamine (TPA) system, a novel type of electrochemiluminescent (ECL) magneto-immunosensor is developed for ultrasensitive detection of hs-cTnI. In this approach, a large amount of [Ru(bpy)(3)](2+) is loaded in SiO2 (silica nanoparticles) as luminophores with high luminescent efficiency and SWCNTs as electrode surface modification material with excellent electrooxidation ability for TPA. Subsequently, a hierarchical micropillar array of microstructures is fabricated with a magnet placed at each end to efficiently confine a single layer of immunomagnetic microbeads on the surface of the electrode and enable 7.5-fold signal enhancement. In particular, the use of transparent SWCNTs to modify a transparent ITO electrode provides a two-order-of-magnitude ECL signal amplification. A good linear calibration curve is developed for hs-cTnI concentrations over a wide range from 10 fg/ml to 10 ng/ml, with the limit of detection calculated as 8.720 fg/ml (S/N = 3). This ultrasensitive immunosensor exhibits superior detection performance with remarkable stability, reproducibility, and selectivity. Satisfactory recoveries are obtained in the detection of hs-cTnI in human serum, providing a potential analysis protocol for clinical applications. (c) 2024 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://***/licenses/by/4.0/).

关键词： Electrochemiluminescent magneto-immunosensor Microfluidic chip High-sensitivity cardiac troponin I Single-walled carbon nanotube [Ru(bpy)(3)](2+)-doped silica nanoparticle

Transparency and reporting characteristics of randomized controlled trials with chinese herbal medicine formulas interventions

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FRONTIERS OF medICINE 2024年第4期18卷 757-761页

作者： Wang, Juan Shi, Dongni Wang, Yaochen Zhang, Xuanqi Li, Han Wang, Xihong Luo, Shufeng Hu, Lihan Deng, Jiashuai Zhang, Lin Lau, Chung Tai Cheng, Chung Wah Han, Fei Li, Ji Wang, Ping Lyu, Aiping Bian, Zhaoxiang Zhang, Xuan Hong Kong Baptist Univ Inst Res & Continuing Educ Shenzhen 518057 Peoples R China Hong Kong Baptist Univ Chinese EQUATOR Ctr Hksar 999077 Peoples R China Hong Kong Baptist Univ Sch Chinese Med Hksar 999077 Peoples R China Hong Kong Baptist Univ Ctr Chinese Herbal Med Drug Dev Hksar 999077 Peoples R China Tianjin Univ Tradit chinese med Sch Tradit Chinese Med Tianjin 301617 Peoples R China Beijing Univ chinese med Sch Chinese Med Beijing 100105 Peoples R China china acad chinese med sci Guanganmen Hosp Dept Pediat Beijing 100053 Peoples R China china acad chinese med sci Xiyuan Hosp Beijing 100091 Peoples R China

Transparency and reporting characteristics of randomized controlled trials with chinese herbal medicine formulas interventions

关键词： Transparency reporting characteristics trials herbal medicine

CpG Island Definition and Methylation Mapping of the T2T-YAO Genome

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GENOMICS PROTEOMICS & BIOINFORMATICS 2024年第2期22卷 qzae009页

作者： Xiao, Ming Wei, Rui Yu, Jun Gao, Chujie Yang, Fengyi Zhang, Le Sichuan Univ Coll Comp Sci Chengdu 610065 Peoples R China Univ chinese acad sci Hangzhou Inst Adv Study Sch Life Sci Key Lab Syst Hlth Sci Zhejiang Prov Hangzhou 310024 Peoples R China chinese acad sci Beijing Inst Genom CAS Key Lab Genome Sci & Informat Beijing 100101 Peoples R China Univ chinese acad sci Beijing 100049 Peoples R China

Precisely defining and mapping all cytosine (C) positions and their clusters, known as CpG islands (CGIs), as well as their methylation status, are pivotal for genome-wide epigenetic studies, especially when population-centric reference genomes are ready for timely application. Here, we first align the two high-quality reference genomes, T2T-YAO and T2T-CHM13, from different ethnic backgrounds in a base-by-base fashion and compute their genome-wide density-defined and position-defined CGIs. Second, by mapping some representative genome-wide methylation data from selected organs onto the two genomes, we find that there are about 4.7%-5.8% sequence divergency of variable categories depending on quality cutoffs. Genes among the divergent sequences are mostly associated with neurological functions. Moreover, CGIs associated with the divergent sequences are significantly different with respect to CpG density and observed CpG/expected CpG (O/E) ratio between the two genomes. Finally, we find that the T2T-YAO genome not only has a greater CpG coverage than that of the T2T-CHM13 genome when whole-genome bisulfite sequencing (WGBS) data from the European and American populations are mapped to each reference, but also shows more hyper-methylated CpG sites as compared to the T2T-CHM13 genome. Our study suggests that future genome-wide epigenetic studies of the chinese populations rely on both acquisition of high-quality methylation data and subsequent precision CGI mapping based on the chinese T2T reference.

关键词： T2T-YAO Position-defined CpG island Density-defined CpG island DNA methylation Genome analysis DNA METHYLATION SURVIVAL DATABASE GENES

Temporal and spatial regulation of biomimetic vascularization in 3D-printed skeletal muscles

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BIO-DESIGN AND MANUFACTURING 2024年第5期7卷 597-610页

作者： Jia, Minxuan Fan, Tingting Jia, Tan Liu, Xin Liu, Heng Gu, Qi chinese acad sci Inst Zool Key Lab Organ Regenerat & Reconstruct State Key Lab Membrane Biol Beijing 100101 Peoples R China Beijing Inst Stem Cell & Regenerat med Beijing 100101 Peoples R China Univ chinese acad sci Beijing 100049 Peoples R China Capital med Univ Beijing Jishuitan Hosp Dept Orthopaed Beijing 100035 Peoples R China chinese acad sci State Key Lab Stem Cell & Reprod Biol Inst Zool Beijing 100101 Peoples R China

In the intricate skeletal muscle tissue, the symbiotic relationship between myotubes and their supporting vasculature is pivotal in delivering essential oxygen and nutrients. This study explored the complex interplay between skeletal muscle and endothelial cells in the vascularization of muscle tissue. By harnessing the capabilities of three-dimensional (3D) bioprinting and modeling, we developed a novel approach involving the co-construction of endothelial and muscle cells, followed by their subsequent differentiation. Our findings highlight the importance of the interaction dynamics between these two cell types. Notably, introducing endothelial cells during the advanced phases of muscle differentiation enhanced myotube assembly. Moreover, it stimulated the development of the vascular network, paving the way for the early stages of vascularized skeletal muscle development. The methodology proposed in this study indicates the potential for constructing large-scale, physiologically aligned skeletal muscle. Additionally, it highlights the need for exploring the delicate equilibrium and mutual interactions between muscle and endothelial cells. Based on the multicell-type interaction model, we can predict promising pathways for constructing even more intricate tissues or organs. [GRAPHICS] .

关键词： Skeletal muscle Vascularization 3D bioprinting Cell interaction

Structural design of mid-infrared waveguide detectors based on InAs/GaAsSb superlattice

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JOURNAL OF INFRARED AND MILLIMETER WAVES 2024年第4期43卷 457-463页

作者： Pei, Jin-Di Chai, Xu-Liang Wang, Yu-Peng Zhou, Yi Univ chinese acad sci Hangzhou Inst Adv Study Sch Phys & Optoelect Engn Hangzhou 310024 Peoples R China chinese acad sci Shanghai Inst Tech Phys Key Lab Infrared Imaging Mat & Detectors Shanghai 200083 Peoples R China

In the realm of near-infrared spectroscopy, the detection of molecules has been achieved using on-chip waveguides and resonators. In the mid-infrared band, the integration and sensitivity of chemical sensing chips are often constrained by the reliance on off-chip light sources and detectors. In this study, we demonstrate an InAs/ GaAsSb superlattice mid-infrared waveguide integrated detector. The GaAsSb waveguide layer and the InAs/ GaAsSb superlattice absorbing layer are connected through evanescent coupling, facilitating efficient and highquality detection of mid-infrared light with minimal loss. We conducted a simulation to analyze the photoelectric characteristics of the device. Additionally, we investigated the factors that affect the integration of the InAs/GaAsSb superlattice photodetector and the GaAsSb waveguide. Optimal thicknesses and lengths for the absorption layer are determined. When the absorption layer has a thickness of 0. 3 mu m and a length of 50 mu m, the noise equivalent power reaches its minimum value, and the quantum efficiency can achieve a value of 68. 9%. The utilization of waveguide detectors constructed with III-V materials offers a more convenient means of integrating mid-infrared light sources and achieving photoelectric detection chips.

关键词： InAs/GaAsSb superlattice waveguide detector evanescent coupling GaAsSb waveguide