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Screen Content Coding in HEVC and Beyond
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作者 LIN Tao ZHAO Liping ZHOU Kailun 《ZTE Communications》 2016年第B06期51-58,共8页
1 IntroductionThe screen content coding (SCC) standard [1] for high efficiency video coding (HEVC) is an international standard specially developed for screen content.
关键词 HEVC AVS screen content Coding String Matching VIDEOCODING
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Screen Content Coding with Primary and Secondary Reference Buffers for String Matching and Copying
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作者 Tao Lin Kailun Zhou Liping Zhao 《ZTE Communications》 2015年第4期53-60,共8页
A screen content coding (SCC) algorithm that uses a primary reference buffer (PRB) and a secondary reference buffer (SRB) for string matching and string copying is proposed. PRB is typically the traditional reco... A screen content coding (SCC) algorithm that uses a primary reference buffer (PRB) and a secondary reference buffer (SRB) for string matching and string copying is proposed. PRB is typically the traditional reconstructed picture buffer which provides reference string pixels for the current pixels being coded. SRB stores a few of recently and frequently referenced pixels for repetitive reference by the current pixels being coded. In the encoder, searching of optimal reference string is performed in both PRB and SRB, and either a PRB or SRB string is selected as an optimal reference string on a string-by-string basis. Compared with HM-16.4+SCM-40 reference software, the proposed SCC algorithm can improve coding performance measured by bit-distortion rate reduction of average 4.19% in all-intra configuration for text and graphics with motion category' of test sequences defined by JCT-VC common test condition. 展开更多
关键词 HEVC hnage Coding screen content Coding String Matching Video Coding
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Study of total phenol,flavonoids contents and phytochemical screening of various leaves crude extracts of locally grown Thymus vulgaris 被引量:3
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作者 Mohammad Amzad Hossain Khulood Ahmed Salim AL-Raqmi +2 位作者 Zawan Hamood AL-Mijizy Afaf Mohammed Weli Qasim Al-Riyami 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第9期705-710,共6页
Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al ... Objective:To prepare various crude extracts using different polarities of solvent and to quantitatively evaluate their total phenol,flavonoids contents and phytochemical screening of Thymus vulgaris collected from Al Jabal Al Akhdar,Nizwa.Sultanate of Oman.Methods:The leave sample was extracted with methanol and evaporated.Then it was defatted with water and extracted with different polarities organic solvents with increasing polarities.The prepare hexane,chloroform,ethyl acetate,hutanol and methanol crude extracts were used for their evaluation of total phenol,flavonoids contents and phytochemical screening study.The established conventional metliods were used for quantitative determination of total phenol,flavonoids contents and phytochemical screening.Results:Phytochemical screening for various crude extracts were tested and shown positive result for flavonoids,saponins and steroids compounds.The result for total phenol content was the highest in hutanol and the lowest in methanol crude extract whereas the total flavonoids contents was the highest in methanol and the lowest hexane crude extract.Conclusions:The crude extracts from locally grown Thymus vulgaris showed high concentration of flavonoids and it could be used as antibiotics for different curable and uncurable diseases. 展开更多
关键词 THYMUS VULGARIS L. VARIOUS crude extracts PHYTOCHEMICAL screening SOXHLET EXTRACTOR Total phenol Flavonoids contents.
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Molecular marker for screening rice cultivars with intermediate amylose content in indica 被引量:1
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作者 CAI Xiuling~(1)) LIU Qiaoquan~(2)) TANG Shuzhu~(2)) GU Minghong~(2)) WANG Zongyang~(1)) 1)Shanghai Inst of Plant Physiology,the Chinese Academy of Sciences,Shanghai 200032 2)College of Bioscienee and Biotechnology,Yangzhou Univ,Yangzhou 225009,China 《Chinese Rice Research Newsletter》 2002年第3期7-9,共3页
The waxy(Wx)gene of rice encodes the granule-bound starch synthase(GBSS),which was required in the synthesis of amylose in endosperm.Theamylose content(AC)of rice endosperm played an important role in grain yield,pala... The waxy(Wx)gene of rice encodes the granule-bound starch synthase(GBSS),which was required in the synthesis of amylose in endosperm.Theamylose content(AC)of rice endosperm played an important role in grain yield,palatability,and processing quality.Our previous researehes showed that en-dosperm AC and GBSS contents were correlated with the ability of excising intron1 from the leader sequence of the Wx transcript.Cultivars with high endosperm 展开更多
关键词 GBSS AC Molecular marker for screening rice cultivars with intermediate amylose content in indica
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Content-based image retrieval applied to BI-RADS tissue classification in screening mammography 被引量:1
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作者 Júlia Epischina Engrácia de Oliveira Arnaldo de Albuquerque Araújo Thomas M Deserno 《World Journal of Radiology》 CAS 2011年第1期24-31,共8页
AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classificat... AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classification.METHODS:Breast density is characterized by image texture using singular value decomposition(SVD) and histograms.Pattern similarity is computed by a support vector machine(SVM) to separate the four BI-RADS tissue categories.The crucial number of remaining singular values is varied(SVD),and linear,radial,and polynomial kernels are investigated(SVM).The system is supported by a large reference database for training and evaluation.Experiments are based on 5-fold cross validation.RESULTS:Adopted from DDSM,MIAS,LLNL,and RWTH datasets,the reference database is composed of over 10000 various mammograms with unified and reliable ground truth.An average precision of 82.14% is obtained using 25 singular values(SVD),polynomial kernel and the one-against-one(SVM).CONCLUSION:Breast density characterization using SVD allied with SVM for image retrieval enable the development of a CBIR system that can effectively aid radiologists in their diagnosis. 展开更多
关键词 COMPUTER-AIDED diagnosis content-BASED IMAGE retrieval IMAGE processing screening MAMMOGRAPHY SINGULAR value decomposition Support vector machine
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Identification of berbamine dihydrochloride from barberry as an anti-adipogenic agent by high-content imaging assay 被引量:2
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作者 Shifeng Wang Qiao Zhang +4 位作者 Yuxin Zhang Yanling Zhang Qinghua Wu Shiyou Li Yanjiang Qiao 《Journal of Traditional Chinese Medical Sciences》 2016年第2期91-99,共9页
Objective:Lipid droplet(LD)deposition in adipose tissue is a critical factor leading to metabolic dysfunction.Various herbal medicines in traditional Chinese medicine(TCM)are used to treat hyperlipidemia,type 2 diabet... Objective:Lipid droplet(LD)deposition in adipose tissue is a critical factor leading to metabolic dysfunction.Various herbal medicines in traditional Chinese medicine(TCM)are used to treat hyperlipidemia,type 2 diabetes,obesity,and other diseases.The objective of this study was to identify potential anti-adipogenic agents from TCM herbal compounds.Methods:One hundred and twenty compounds were evaluated in terms of their effect on adipocyte differentiation through image-based high content screening.Anti-adipogenic effects of identified hits were further confirmed at various concentrations.In addition,drug-induced liver injury assay was performed with HepG2 cells to test the hepatotoxicity of hit compounds.Results:Berbamine(BBM),a chemical isolated from barberry,and a derivative of BBM,berbamine dihydrochloride(BBMD),reduced LDs formation by more than 50%.Dose-dependent effects were observed and the IC50 values of the two hits,BBM and BBMD,were determined as 1.88 mM and 0.95 mM,respectively.Moreover,BBM induced mild HepG2 cell injury,while its dihydrochloridedBBMD did not exhibit hepatotoxicity within 40 mM.Conclusion:This study demonstrates that BBMD may be a potential therapeutic candidate for disorders associated with elevated LDs accumulation. 展开更多
关键词 3T3-L1 adipocyte Berbamine dihydrochloride HEPATOTOXICITY High content screening Lipid droplet
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Antioxidant activity and phytochemical screening of the methanol extracts of Euphorbia hirta L 被引量:7
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作者 Abu Arra Basma Zuraini Zakaria +1 位作者 Lacimanan Yoga Latha Sreenivasan Sasidharan 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第5期386-390,共5页
Objective:To assess antioxidant activities of different parts of Euphorbia hirta(E.hirta),and to search for new sources of safe and inexpensive antioxidants.Methods:Samples of leaves,stems, flowers and roots from E.... Objective:To assess antioxidant activities of different parts of Euphorbia hirta(E.hirta),and to search for new sources of safe and inexpensive antioxidants.Methods:Samples of leaves,stems, flowers and roots from E.hirta were tested for total phenolic content,and flavonoids content and in vitro antioxidant activity by diphenyl-1-picrylhydrazyl(DPPH) assay and reducing power was measured using cyanoferrate method.Results:The leaves extract exhibited a maximum DPPH scavenging activity of(72.96±0.78)%followed by the flowers,roots and stems whose scavenging activities were(52.45±0.66)%,(48.59±0.97)%,and(44.42±0.94)%,respectively.The standard butylated hydroxytoluene(BHT) was(75.13±0.75)%.The IC<sub>50</sub>,for leaves,flowers,roots,stems and BHT were 0.803,0.972,0.989,1.358 and 0.794 mg/mL,respectively.The reducing power of the leaves extract was comparable with that of ascorbic acid and found to be dose dependent. Leaves extract had the highest total phenolic content[(206.17±1.95) mg GAE/g],followed by flowers,roots and stems extracts which were(117.08±3.10) mg GAE/g,(83.15±1.19) mg GAE/g,and (65.70±1.72) mg GAE/g,respectively.On the other hand,total flavonoids content also from leave had the highest value[(37.970±0.003) mg CEQ/g],followed by flowers,roots and stems extracts which were(35.200±0.002) mg CEQ/g,(24.350±0.006) mg CEQ/g,and(24.120±0.004) mg CEQ/ g,respectively.HPTLC bioautography analysis of phenolic and antioxidant substance revealed phenolic compounds.Phytochemical screening of E.hirta leaf extract revealed the presence of reducing sugars,terpenoids,alkaloids,steroids,tannins,flavanoids and phenolic compounds. Conclusions:These results suggeste that E.hirta have strong antioxidant potential.Further study is necessary for isolation and characterization of the active antioxidant agents,which can be used to treat various oxidative stress-related diseases. 展开更多
关键词 Antioxidant EUPHORBIA hirta L DPPH SCAVENGING Reducing power TOTAL phenolics content TOTAL FLAVONOIDS content PHYTOCHEMICAL screening
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Comparative Study on Grain Cadmium Content and Yield in Different Rice Varieties
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作者 Weiqing FU Peng DU +1 位作者 Jing ZHOU Guiyuan MENG 《Agricultural Biotechnology》 CAS 2019年第5期86-89,共4页
[Objectives] The rice varieties with a low cadmium (Cd) content and a high yield were screened to provide reference for further experiments on moderate and high Cd-contaminated soils and local promotion.[Methods] Unde... [Objectives] The rice varieties with a low cadmium (Cd) content and a high yield were screened to provide reference for further experiments on moderate and high Cd-contaminated soils and local promotion.[Methods] Under the soil condition of a Cd content of 0.58mg/kg,differences in agronomic traits such as grain Cd content,yield,number of effective panicles,number of grains per panicle and 1 000-grain weight of 26 different rice varieties such as Huanghuazhan,Y Liangyou 9918 and T You 109,were studied by pot experiment.[Results] Such six varieties as Xiangyou 109,Tianfengyou 316,C Liangyou 651,Y Liangyou 3218,Y Liangyou 9918 and T You 109 had a relatively higher yield and relatively lower Cd content,which was because that their traits including panicle length,number of effective panicles and 1 000-grain weight were superior to other varieties.The correlation analysis between plant Cd content and yield showed that there was a negative correlation between Cd content and yield in rice.[Conclusions] This study provides a theoretical basis for cultivating suitable varieties in this area. 展开更多
关键词 RICE VARIETY CADMIUM content YIELD screening
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Study on drying rate in contact drying with flexible screen
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作者 王伟宏 陆仁书 张显权 《Journal of Forestry Research》 CAS CSCD 2000年第1期54-56,共3页
The moisture contents (MC) of popular veneers were tested in Composition Board Laboratory of Northeast Forestry University by contact drying with flexible screen. The influence factors considered included temperature,... The moisture contents (MC) of popular veneers were tested in Composition Board Laboratory of Northeast Forestry University by contact drying with flexible screen. The influence factors considered included temperature, initial moisture contents (IMC), and veneer thickness. Veneer-drying laws under different hot press conditions were analyzed. The results showed that the drying rate increased with temperature rising. 160°C was considered to be more efficient than 140°C and 180°C because excessive high temperature has no significant contribution to drying rate. IMC had significant effect on drying rate. The veneer with high IMC had a higher drying rate at above fiber saturation point (FSP) and a lower drying rate at below FSP, compared to the veneer with low IMC. Average drying rate also varied with thickness in power law. 展开更多
关键词 Drying rate Contact drying Flexible screen TEMPERATURE Initial moisture content Veneer thickness
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HPTLC Phytochemical Screening and Hydrophilic Antioxidant Activities of <i>Apium graveolens</i>L., <i>Cleome gynandra</i>L., and <i>Hibiscus sabdariffa</i>L. Used for Diabetes Management
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作者 Moumouni Koala Alphonsine Ramde-Tiendrebeogo +4 位作者 Noufou Ouedraogo Sylvain Ilboudo Boukaré Kaboré Félix B. Kini Sylvin Ouedraogo 《American Journal of Analytical Chemistry》 2021年第1期15-28,共14页
Diabetes mellitus is a socially significant disease characterized by chronic hyperglycemia and metabolic disorders of proteins, carbohydrates, and lipids due to reduced function of insulin. Medicinal plants, rich in b... Diabetes mellitus is a socially significant disease characterized by chronic hyperglycemia and metabolic disorders of proteins, carbohydrates, and lipids due to reduced function of insulin. Medicinal plants, rich in bioactive components that promote prevention and treatment, are inexpensive and no side effects. <i>Apium graveolens</i>, <i>Cleome gynandra</i>, and <i>Hibiscus sabdariffa</i> from Burkina Faso were investigated for their phytochemical profile and antioxidant activities. The high-performance thin-layer chromatography profile revealed flavonoids, tannins, and sterols in these herbaceous. The <i>Hibiscus sabdariffa</i> methanolic extract exhibited the highest total phenolic (138.4 ± 0.5 mg GAE/g DW) and flavonoid (52.8 ± 0.6 mg RuE/g DW) contents comparatively to <i>Cleome gynandra</i> and <i>Apium graveolens</i>. <i>Hibiscus sabdariffa</i> methanolic extract also presented the highest antioxidant activity (IC<sub>50</sub> = 0.31 ± 0.002 mg/mL) using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay. A high correlation between flavonoid contents and hydrophilic antioxidant activities (r = 0.99) was observed, indicating that flavonoids contribute significatively to these herbaceous antioxidant properties. <i>Apium graveolens</i>, <i>Cleome gynandra, and <i>Hibiscus sabdariffa</i> constitute a natural source of phenolic compounds that could be exploited in diabetes mellitus management.</i> 展开更多
关键词 Diabetes Mellitus Medicinal Plants Flavonoids contents Hydrophilic Antioxidant Activity HPTLC screening
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Prediction of Salt Tolerance in Rice (Oryza Sativa) Based on Shoot Ion Content under Non-Stressed Conditions
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作者 Souleymane Bado Brian Peter Forster +7 位作者 Roman Padilla-Alvarez Christian Resch Alessandro Migliori Yacouba Diawara Milko Jaksic Abdelbagi Mukhtar Ali Ghanim Stephen Nielen Margit Laimer 《材料科学与工程(中英文A版)》 2016年第1期1-16,共16页
关键词 水稻基因型 耐盐性 ORYZA 离子含量 应激 非遗传因素 多变量统计分析 元素含量
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Using Prostatic Fluid Levels of Some Trace Elements and Their Combinations in Non-Invasive and Highly Accurate Screening for Prostate Cancer
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作者 Vladimir Zaichick 《Journal of Cancer Therapy》 2020年第1期1-17,共17页
Objective: Prostate specific antigen (PSA) does not provide the high reliability and precision that is required for an accurate screening for prostate cancer?(PCa). The aim of our study was to search for a simple, rap... Objective: Prostate specific antigen (PSA) does not provide the high reliability and precision that is required for an accurate screening for prostate cancer?(PCa). The aim of our study was to search for a simple, rapid, direct, preferably non-invasive, and highly accurate biomarker and procedure for the screening for PCa. Method: The levels of trace elements (TE) Br, Fe, Rb, Sr,?and Zn were prospectively evaluated in expressed prostatic fluid (EPF). Also?Zn/Br, Zn/Fe, Zn/Rb, Zn/Sr concentration ratios as well as ZnRb and (ZnRb)/Fe concentration combinations were calculated for EPF samples, obtained from 38 apparently healthy males and from 33, 51, and 24 patients with chronic prostatitis, benign prostatic hyperplasia, and PCa, respectively. Measurements were performed using an energy dispersive X-ray fluorescent (EDXRF) microanalysis. Results: It was found that in the EPF of cancerous prostates the levels of Rb, Zn, Zn/Br, Zn/Fe, Zn/Sr, ZnRb, and (ZnRb)/Fe were significantly lower in comparison with those in the EPF of normal, inflamed, and hyperplastic prostates. For example, in comparison hyperplastic?with cancerous prostates p values obtained using Student’s t-test and?Wilcoxon-Mann-Whitney U-test were Conclusions: The levels of TE and their combinations in EPF, obtained by EDXRF, is a fast, reliable, andnon-invasive diagnostic tool that can be successfully used by local, non- urologist physicians at the point-of-care to provide a highly effective PCa screening and as an additional confirmatory test before a prostate gland biopsy. 展开更多
关键词 UROLOGY screening Prostate Cancer EXPRESSED PROSTATIC Fluid Trace Element content Energy-Dispersive X-Ray Fluorescent Analysis
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富硒大豆根瘤菌的筛选鉴定及对大豆生长发育和硒积累的影响 被引量:1
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作者 胡叶青 张杰 +4 位作者 何婷婷 张悦 李从虎 刘芸双 胡婷 《湖北农业科学》 2025年第4期58-63,共6页
从富硒大豆根瘤中筛选、鉴定出耐硒根瘤菌,分别采用硒酸钠、亚硒酸钠作为硒源,设定不同浓度梯度,研究根瘤菌的耐硒情况;并以中黄301为试验材料,采用田间试验,设置空白对照(CK)、根瘤菌处理(Rb)、亚硒酸钠处理(Se)、根瘤菌与亚硒酸钠结... 从富硒大豆根瘤中筛选、鉴定出耐硒根瘤菌,分别采用硒酸钠、亚硒酸钠作为硒源,设定不同浓度梯度,研究根瘤菌的耐硒情况;并以中黄301为试验材料,采用田间试验,设置空白对照(CK)、根瘤菌处理(Rb)、亚硒酸钠处理(Se)、根瘤菌与亚硒酸钠结合处理(Rb+Se),考察根瘤菌与硒元素结合处理对大豆[Glycine max(Linn.)Merr.]生长发育、硒积累的影响。结果表明,1.0 mg/L亚硒酸钠处理对根瘤菌生长具有一定的促进作用。与CK相比,Rb+Se处理大豆株高、主根长、单株干重分别提高78.67%、82.98%、69.57%,根、茎、叶、子粒、根瘤的硒含量分别提高3.53、2.44、1.37、2.63、1.82倍,土壤硒含量提高2.10倍;与Rb处理相比,Rb+Se处理大豆株高、主根长、单株干重分别提高21.45%、32.31%、14.71%,根、茎、叶、子粒、根瘤的硒含量分别提高113.04%、173.33%、65.21%、160.70%、49.50%,土壤硒含量提高125.65%;与Se处理相比,Rb+Se处理大豆株高、主根长、单株干重分别提高45.13%、56.31%、50.00%,根、茎、叶、子粒、根瘤的硒含量分别提高30.14%、50.01%、27.96%、22.59%、18.19%,土壤硒含量提高19.23%。由此可见,根瘤菌与硒元素的结合处理有利于大豆的生长发育,能够提高大豆各部位硒含量,同时对栽培土壤中硒积累也有一定提升。 展开更多
关键词 富硒大豆[Glycine max(Linn.)Merr.] 根瘤菌 耐硒 筛选 鉴定 大豆生长 硒含量
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屏幕内容图像质量客观评价方法综述
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作者 周子镱 董武 +3 位作者 张艳 陆利坤 曾庆涛 马倩 《印刷与数字媒体技术研究》 北大核心 2025年第1期14-27,共14页
在交互式多媒体中,屏幕内容图像客观质量评价有广泛的应用价值。本文首先阐述了屏幕内容图像和自然图像的区别;然后分析了基于手工提取特征和基于深度学习自动提取特征两种屏幕内容图像评价算法;接着总结了常用的评价指标和屏幕内容图... 在交互式多媒体中,屏幕内容图像客观质量评价有广泛的应用价值。本文首先阐述了屏幕内容图像和自然图像的区别;然后分析了基于手工提取特征和基于深度学习自动提取特征两种屏幕内容图像评价算法;接着总结了常用的评价指标和屏幕内容图像数据集,并对屏幕内容图像质量评价算法的性能进行比较;最后对屏幕内容图像质量评价算法的研究进行展望。本文有助于研究人员深入理解该领域的研究现状,为推动其技术的发展和应用提供指导和支持。 展开更多
关键词 屏幕内容图像 客观质量评价 深度学习 人眼视觉特性
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基于多任务注意力机制的无参考屏幕内容图像质量评价算法
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作者 周子镱 董武 +3 位作者 陆利坤 马倩 侯国鹏 张二青 《光电工程》 北大核心 2025年第4期106-119,共14页
提出一种基于多任务注意力机制的无参考屏幕内容图像质量评价算法(multi-task attention mechanism based no reference quality assessment algorithm for screen content images,MTA-SCI)。MTA-SCI首先使用自注意力机制提取屏幕内容... 提出一种基于多任务注意力机制的无参考屏幕内容图像质量评价算法(multi-task attention mechanism based no reference quality assessment algorithm for screen content images,MTA-SCI)。MTA-SCI首先使用自注意力机制提取屏幕内容图像的全局特征,增强对屏幕内容图像整体信息的表征能力;然后使用综合局部注意力机制提取屏幕内容图像的局部特征,使局部特征能够聚焦于屏幕内容图像中更吸引人注意的细节部分;最后使用双通道特征映射模块预测屏幕内容图像的质量分数。在SCID和SIQAD数据集上,MTA-SCI的斯皮尔曼秩序相关系数(Spearman's rank order correlation coefficient,SRCC)分别达到0.9602和0.9233,皮尔森线性相关系数(Pearson linear correlation coefficient,PLCC)分别达到0.9609和0.9294。实验结果表明,MTA-SCI在预测屏幕内容图像质量任务中具有较高的准确性。 展开更多
关键词 屏幕内容图像 无参考图像质量评价 vision transformer 多级视觉感知特性 注意力机制
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盐酸左西替利嗪口服溶液抑菌体系的评价研究
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作者 王静 周发友 +3 位作者 戴翚 肖璜 曹蕊 马仕洪 《中国现代应用药学》 北大核心 2025年第3期430-436,共7页
目的对2021年国家药品评价性抽验品种盐酸左西替利嗪口服溶液的抑菌效力及其抑菌剂使用情况进行评价,分析其抑菌体系对微生物污染的控制能力。方法参照中国药典2020年版二部阿昔洛韦滴眼液的方法对8家企业的样品开展抑菌剂种类筛查;根... 目的对2021年国家药品评价性抽验品种盐酸左西替利嗪口服溶液的抑菌效力及其抑菌剂使用情况进行评价,分析其抑菌体系对微生物污染的控制能力。方法参照中国药典2020年版二部阿昔洛韦滴眼液的方法对8家企业的样品开展抑菌剂种类筛查;根据企业提供的方法对添加抑菌剂的6家企业的样品进行抑菌剂含量测定;根据中国药典2020年版四部通则1121抑菌效力检查法,评判样品的抑菌性是否满足药典要求。结果8家企业所有样品抑菌剂的种类、添加量均与处方一致。抑菌效力检查结果显示,添加抑菌剂的6家企业的样品均满足药典规定,未添加抑菌剂的2家企业的样品,1家满足规定、1家不满足规定。结论抽验的盐酸左西替利嗪口服溶液均未发现违规添加或滥用抑菌剂的情况,但抑菌体系是否为最优处方存疑,建议生产企业结合辅料特性、水分活度等,基于风险评估的理念开展评价,优化处方设计,建立更合理的抑菌体系。 展开更多
关键词 盐酸左西替利嗪口服溶液 尼泊金酯类抑菌剂 抑菌体系 抑菌效力 种类筛查 含量测定
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表达EGFP的重组LSDV的构建以及在高效筛选抗病毒药物中的应用
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作者 刘聪 钱炳旭 +3 位作者 温渊 汤芳 戴建君 薛峰 《中国兽医科学》 北大核心 2025年第2期188-196,共9页
为实现抗牛结节性皮肤病病毒(LSDV)药物的高内涵筛选(HCS),选取LSDV复制非必需基因TK作为增强绿色荧光蛋白(EGFP)的插入区域,构建了表达EGFP的重组LSDV,该重组病毒rLSDV-ΔTKEGFP与野生型LSDV的生长特性无明显差异。基于rLSDV-ΔTK-EGFP... 为实现抗牛结节性皮肤病病毒(LSDV)药物的高内涵筛选(HCS),选取LSDV复制非必需基因TK作为增强绿色荧光蛋白(EGFP)的插入区域,构建了表达EGFP的重组LSDV,该重组病毒rLSDV-ΔTKEGFP与野生型LSDV的生长特性无明显差异。基于rLSDV-ΔTK-EGFP,建立了抗LSDV药物的高内涵快速筛选方法,使用该方法对天然产物库中的1036个化合物进行了筛选。结果显示,该方法筛选到5个具有抗LSDV活性的化合物。进一步检测LSDV117蛋白表达水平和LSDV043基因拷贝数,结果表明,在MDBK细胞上经过5种化合物处理后可以显著抑制LSDV,且化合物浓度为10μmol/L时,均无明显细胞毒性。上述结果表明,构建的表达EGFP的重组LSDV可以用于抗LSDV药物的高内涵筛选,具有较高的筛选效率,对于提高动物个体抗病毒能力,缓解牛结节性皮肤病症状,减少经济损失等方面具有重要意义。 展开更多
关键词 牛结节性皮肤病病毒 EGFP 抗病毒药物 高内涵筛选
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木香中2个新的倍半萜及其法尼醇X受体激动活性研究
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作者 陈芊羽 黄丹 +3 位作者 詹洪洪 孟凡成 王国伟 陈敏 《中国中药杂志》 北大核心 2025年第7期1810-1816,共7页
综合运用多种色谱学方法对木香乙酸乙酯提取物进行化学成分研究,并结合化合物的理化性质和波谱学数据分析鉴定化合物结构,共分离鉴定了2个倍半萜类新化合物,分别为auclappsine A(1)和auclappsine B(2)。通过体外高内涵活性筛选,采用固... 综合运用多种色谱学方法对木香乙酸乙酯提取物进行化学成分研究,并结合化合物的理化性质和波谱学数据分析鉴定化合物结构,共分离鉴定了2个倍半萜类新化合物,分别为auclappsine A(1)和auclappsine B(2)。通过体外高内涵活性筛选,采用固甾酮诱导的L02细胞模型,考察化合物对法尼醇X受体(FXR)蛋白表达的影响。结果显示,化合物1具有显著的FXR激活作用,为研制治疗肝胆疾病的药物提供了科学依据。 展开更多
关键词 木香 倍半萜 法尼醇X受体 高内涵筛选
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低含水率黄土盾构隧道壁后注浆筛滤扩散模型研究
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作者 张才飞 叶飞 +3 位作者 李思翰 夏天晗 张俊元 韩兴博 《人民长江》 北大核心 2025年第11期261-268,共8页
为得到适用于低含水率黄土盾构隧道壁后注浆浆液的扩散模型,首先通过计算黄土地层的渗透系数,总结渗透扩散的常见形式并分析浆液的可注标准,综合判定给出了浆液的筛滤扩散形式;然后建立筛滤扩散模型,推导出了滤液扩散距离和滤饼沉积厚... 为得到适用于低含水率黄土盾构隧道壁后注浆浆液的扩散模型,首先通过计算黄土地层的渗透系数,总结渗透扩散的常见形式并分析浆液的可注标准,综合判定给出了浆液的筛滤扩散形式;然后建立筛滤扩散模型,推导出了滤液扩散距离和滤饼沉积厚度的计算公式;最后通过实例参数分析,得到了单位滤液形成的滤饼体积、盾尾间隙厚度和地层渗透系数变化对滤饼沉积及滤液扩散的影响。结果表明:在低含水率黄土盾构隧道壁后注浆中,浆液发生筛滤扩散;滤饼沉积和滤液扩散同步开始并同步结束;滤饼沉积用时随着单位滤液形成滤饼体积的增大、盾尾间隙厚度的减小及渗透系数的减小而减小;滤液最远扩散距离随着单位滤液形成滤饼体积的减小及盾尾间隙厚度的增大而增大,而地层渗透系数的变化对其几乎无影响。研究成果可为工程实践中注浆停止时间的控制提供参考。 展开更多
关键词 盾构隧道 壁后注浆 低含水率黄土 筛滤扩散 滤饼沉积
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基于植被指数特征优选的冬小麦叶片含水量估算 被引量:1
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作者 马宇欣 胡笑涛 +4 位作者 王亚昆 范晓懂 彭雪莲 孙骏 陈洪 《麦类作物学报》 北大核心 2025年第2期234-244,共11页
为进一步提升利用高光谱数据快速监测叶片含水量的能力,以关中地区冬小麦为研究对象,分别获取2022和2023年孕穗期、抽穗期及灌浆期冬小麦叶片含水量,并同步监测叶片高光谱信息。通过波段组合的形式构建植被指数,并利用相关性分析进行初... 为进一步提升利用高光谱数据快速监测叶片含水量的能力,以关中地区冬小麦为研究对象,分别获取2022和2023年孕穗期、抽穗期及灌浆期冬小麦叶片含水量,并同步监测叶片高光谱信息。通过波段组合的形式构建植被指数,并利用相关性分析进行初步筛选,再以ReliefF算法优选得到输入特征变量,然后分别利用随机森林(random forest,RF)、长短期记忆(long short-term memory,LSTM)网络和基于粒子群(particle swarm optimization,PSO)优化的反向传播神经网络(back propagation neural network,BPNN)构建冬小麦叶片含水量估算模型,并进行精度评价。结果表明,通过相关性分析与ReliefF算法结合优选变量,能够较单独通过相关分析明显提升LSTM和PSO-BPNN模型的建模精度,但对RF模型则无法优化变量。相关性分析与ReliefF结合后PSO-BPNN模型在各生育时期均取得最佳预测结果,其中孕穗期、抽穗期和灌浆期验证集r2分别为0.816、0.736和0.806,RMSE分别为0.546%、0.899%和1.531%,NRMSE分别为0.681%、1.195%和2.185%。由此可见,在相关分析的基础上,通过ReliefF算法优选特征变量能够提升特定模型对冬小麦叶片含水量的估算精度,其中对PSO-BPNN模型的效果最好。 展开更多
关键词 冬小麦 叶片含水量 机器学习 变量筛选 植被指数
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