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Image Enhancement based on Human Visual Model
Cheng Yanyan,Yuan Quanbo 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.2
This paper mainly study traditional histogram image enhancement method. Aiming at the lack of image enhancement, a method based on human visual model was proposed, and the experimental results show that this algorithm has better performance than is a traditional histogram equalization method, which provided a good direction studying image enhancement algorithm.
Digital Image Enhancement Method based on Image Complexity
Cheng Yanyan,Wang Huijuan,Mi Xinjiang 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.6
In this paper, aiming at the shortcomings of the traditional histogram enhancement method and defect, a kind of image enhancement algorithm is put forward based on digital image complexity. Experimental results show that this method has advantages compared with traditional image enhancement algorithms, mainly reflected in the results obtained by using the improved image enhancement algorithms, the corresponding SNR and MSSIM index are higher than the original. In the paper, SNR and MSSIM index is proved best combination, which are high reflects that the similarity of after-image and the reference image and the image is more suitable to the human eye.
Yanyan Liu,Yue Cheng,Haifei Yang,Li-Fen Hu,Jun Cheng,Ying Ye,Jia-Bin Li 대한진단검사의학회 2017 Annals of Laboratory Medicine Vol.37 No.5
Background: The emergence of fosfomycin resistance and extended-spectrum β-lactamase (ESBL) genes is a serious threat to public health and a new challenge in shigellosis treatment. The purpose of this study was to identify fosfomycin resistance and characterize β-lactamase genes in fos-carrying isolates of Shigella flexneri from patients in China. Methods: A total of 263 S. flexneri isolates were collected from 34 hospitals in the Anhui Province of China during September 2012-September 2015 and screened for fosA3, fosA, and fosC2 by PCR amplification and sequencing. The fos-carrying isolates were then screened for β-lactamase genes. The clonal relationships between fosA3-carrying isolates, the transmissibility of fosfomycin resistance, replicon types of plasmids carrying fosfomycin resistance genes and other associated resistance genes were investigated. Results: Twenty-five of the 263 isolates (9.5%) showed resistance to fosfomycin, and 18 (6.8%) were positive for fosA3. None of the isolates was positive for fosA or fosC2. Seventeen of the isolates carrying fosA3 (94%) were CTX-M producers (seven CTX-M-55, five CTX-M-14, and five CTX-M-123), while three (16.7%) were TEM producers (TEM-1).Sixteen (88.9%) fosA3-carrying isolates exhibited multi-drug resistance. The replicon types of the 13 fosA3-carrying plasmids were IncF (n=13), IncHI2 (n=3), IncIl-Ir (n=2), and IncN (n=1). Conclusions: Our results indicated that fosA3 could spread through plasmids in S. flexneri isolates, along with the blaCTX-M and blaTEM, which facilitate its quick dispersal. To the best of our knowledge, this is the first report of CTX-M-123-type ESBLs in S. flexneri isolates from patients in China.
Sperm maturation screening and the effect of ecdysone on sperm development of silkworm Bombyx mori
Cheng Hao,Wang Yanyan,Chang Meiling,Zhang Kun,Cai Zhiyan,Qian Yuxin,Li Dandan 한국응용곤충학회 2022 Journal of Asia-Pacific Entomology Vol.25 No.2
There are two sperm morphs of silkworm, the nucleated spermatozoa (eupyrene) and anucleated spermatozoa (apyrene). Eupyrene sperm cannot complete fertilization successfully without the apyrene sperm. Here a modified rapid and efficient method for sperm identification was developed, after 10 s of fixation in para formaldehyde and 30 s of 4 ′ 6-diamidino-2-phenylindole (DAPI) or propidium Iodide (PI) staining, the sperm bundles can be detected easily using a fluorescence microscope. Sperm maturation process of silkworm from the fifth instar larvae to the adult was described with the above method, the precise time of earliest elongate apyrene bundles was detected on day 2 of pre-pupation, with a ratio of 5% in total sperm bundles, after which the percentage of apyrene sperm bundles increased rapidly and attained a relatively stable ratio of 75% at the end of pupation and nearly 80% after eclosion. Delayed mating leads to apyrene sperm accumulation and damaged fertilization. Previous study showed that ecdysone can increase the frequency of apyrene sperm bundles in vitro. Here 20-hydroxyecdysone (20E) was injected into hemolymph of the 2-d-old fifth instar larvae, the worms entered into mounting period after three days injection, but no apyrene sperm bundles were induced unless day 2 of pre-pupation. Interestingly, maturation of eupyrene sperm bundles were accelerated, and the ratio of eupyrene sperm bundles increased and exhibited a dose-dependent effect after 20E injection, which indicated that the development of eupyrene sperm can be accelerated by ecdysone before pupation of silkworm in vivo. These results will provide new clues for lepidopteran pest control.
Decomposed Fliess Functional Expansion and Its Application to Attitude Control of Missiles
Daizhan Cheng,Yupeng Qiao,Yanyan Yuan 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8
This paper investigates the Fliess functional expansion of input-output decomposable systems. It is proved that under suitable state feedback the closed-loop system has a Fliess functional expansion of finite terms. This form has two advantages: (1) providing a precise input-output mapping; (2) tremendously reducing the complexity of computation and making the online control design available. It is proved that the model of attitude control of missiles satisfies this decomposable requirement. Hence, the finite Fliess functional expansion technique is applicable to it. Detailed algorithm is provided for the design of attitute control.
3D Bioprinted GelMA/PEGDA Hybrid Scaffold for Establishing an In Vitro Model of Melanoma
( Jiahui Duan ),( Yanyan Cao ),( Zhizhong Shen ),( Yongqiang Cheng ),( Zhuwei Ma ),( Lijing Wang ),( Yating Zhang ),( Yuchuan An ),( Shengbo Sang ) 한국미생물생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.4
Due to the high incidence of malignant melanoma, the establishment of in vitro models that recapitulate the tumor microenvironment is of great biological and clinical importance for tumor treatment and drug research. In this study, 3D printing technology was used to prepare GelMA/PEGDA composite scaffolds that mimic the microenvironment of human malignant melanoma cell (A375) growth and construct in vitro melanoma micro-models. The GelMA/PEGDA hybrid scaffold was tested by the mechanical property, cell live/dead assay, cell proliferation assay, cytoskeleton staining and drug loading assay. The growth of tumor cells in two- and three-dimensional culture systems and the anti-cancer effect of luteolin were evaluated using the live/dead staining method and the Cell Counting Kit-8 (CCK-8) method. The results showed a high aggregation of tumor cells on the 3D scaffold, which was suitable for long-term culture. Cytoskeleton staining and immunofluorescent protein staining were used to evaluate the degree of differentiation of tumor cells under 2D and 3D culture systems. The results indicated that 3D bioprinted scaffolds were more suitable for tumor cell expansion and differentiation, and the tumor cells were more aggressive. In addition, luteolin was time- and dose-dependent on tumor cells, and tumor cells in the 3D culture system were more resistant to the drug.
Sui Guanghui,Cheng Yanyan,Chen Kai,Huang Zhifang,Luo MingHong 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.3
Biomass tar is a by-product generated during biomass gasifi cation. Because of the toxic and harmful nature of biomass tar, its treatment method has become the concern of environmental protection fi eld and related researchers. In this paper, biomass tar was separated into the heavy tar and the phenol-containing liquor after enrichment. Porous carbon (PCs) was prepared using the heavy tar by one-step carbonization activation. The results show that PC_3 has the highest specifi c surface area of 352 m 2 g −1 and mesoporosity ratio of 56.25%. The as-prepared electrode displayed an excellent electrochemical performance for portable super-capacitors, which is a volumetric capacitance of 349 F cm −3 . Assembled super-capacitors have an energy density of 21.65 Wh kg −1 at a power density of 123 W kg −1 . The bio-resins were modifi ed with the phenolcontaining liquor. The results showed that the thermal stability of modifi ed resins had been improved and the structure did not change signifi cantly. This research provides an environmentally friendly and comprehensive utilisation methods for the utilisation of biomass tar.
Preparation and In Vitro Characterization of Gelatin Methacrylate for Corneal Tissue Engineering
Yan Yayun,Cao Yanyan,Cheng Rong,Shen Zhizhong,Zhao Yajing,Zhang Yixia,Zhou Guohong,Sang Shengbo 한국조직공학과 재생의학회 2022 조직공학과 재생의학 Vol.19 No.1
BACKGROUND: Corneal disease is second only to cataract considered as the leading cause of blindness in the world, with high morbidity. Construction of corneal substitutes in vitro by tissue engineering technology to achieve corneal regeneration has become a research hotspot in recent years. We conducted in-depth research on the biocompatibility, physicochemical and mechanical properties of rat bone marrow mesenchymal stem cells (rBM-MSCs)-seeded gelatin methacrylate (GelMA) as a bioengineered cornea. METHODS: Four kinds of GelMA with different concentrations (7, 10, 15 and 30%) were prepared, and their physicchemical, optical properties, and biocompatibility with rBM-MSCs were characterized. MTT, live/dead staining, cell morphology, immunofluorescence staining and gene expression of keratocyte markers were performed. RESULTS: 7%GelMA hydrogel had higher equilibrium water content and porosity, better optical properties and hydrophilicity. In addition, it is more beneficial to the growth and proliferation of rBM-MSCs. However, the 30%GelMA hydrogel had the best mechanical properties, and could be more conducive to promote the differentiation of rBM-MSCs into keratocyte-like cells. CONCLUSION: As a natural biological scaffold, GelMA hydrogel has good biocompatibility. And it has the ability to promote the differentiation of rBM-MSCs into keratocyte-like cells, which laid a theoretical and experimental foundation for further tissue-engineered corneal stromal transplantation, and provided a new idea for the source of seeded cells in corneal tissue engineering.
Haifei Yang,Guosheng Chen,Jun Cheng,Yanyan Liu,Li-Fen Hu,Ying Ye,Jia-Bin Li 대한진단검사의학회 2014 Annals of Laboratory Medicine Vol.34 No.6
Sir, Serratia marcescens , once considered to be an innocuous and non-pathogenic organism, is now an important cause of hospital- acquired infections. This organism is associated with respiratory tract infections, urinary tract infections, septicemia, meningitis, and wound infections [1, 2]. S. marcescens infections are difficult to treat because of high resistance to a wide variety of antibiotics, including cephalosporins, fluoroquinolones, and aztreonam [2].