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Verticality Detection Algorithm Based on Local Image Sharpness Criterion

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 173-178页

作者： ZHANG Jin WANG zhong ye Shenghua YANG Chun LI Lin State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

In the high precision image measurement system, the verticality error between the axis of the shooting system and the measured object can bring error of the measurement result. The high demand of the system’s vertical degree is raised by measure system due to the demands of high precision and disposable full field imaging in the micro-parts imaging measurement. The existing method of optical axis verticality detection cannot meet the demand all. In order to achieve the high-precision adjustment of the system optical axis, the algorithm of detecting verticality based on regional image definition is proposed. First, the objected standard image is divided into fixed area. Then, the object plane is moved from the downside to the upside of the focus plane, meanwhile, recording the definition function values of each standard image region at each step, and fitting out the clearest positions of the regions. Finally, according to the inter-regional relations between the locations and the height difference of the each regional clearest position, the small angle between the optical axis and the measured surface can be calculated. The experiment is based on the given image of lithography template with the scale of 10 μm as move unit, and the results show that this method effective reduced the small angle between the system optical axis and the measured body in high-precision image measuring system, the evaluation accuracy is less than 0.1°, meeting the requirements in high-precision measurement. The proposed method of detecting verticality based on regional image definition can evaluate the verticality error between the axis of the shooting system and the measured object accurately, effectively and conveniently.

关键词： verticality detection image definition optical axis adjustment

Recent progress on betulinic acid and its derivatives as antitumor agents:a mini review

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Chinese Journal of Natural Medicines 2021年第9期19卷 641-647页

作者： zhong ye LIANG Nan LIU Yang CHENG Mao-Sheng Key Laboratory of Structure-Based Drug Design&Discovery of Ministry of Education School of Pharmaceutical EngineeringShenyang Pharmaceutical UniversityShenyang 110016China

Natural products are one of the important sources for the discovery of new *** acid(BA),a pentacyclic triterpenoid widely distributed in the plant kingdom,exhibits powerful biological effects,including antitumor activity against various types of cancer cells.A considerable number of BA derivatives have been designed and prepared to remove their disadvantages,such as poor water solubility and low *** review summarizes the current studies of the structural diversity of antitumor BA derivatives within the last five years,which provides prospects for further research on the structural modification of betulinic acid.

关键词： Betulinic acid Natural products Structural modification Derivatives Antitumor activity

Robust Text Detection in Natural Scenes Using Text Geometry and Visual Appearance

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International Journal of Automation and computing 2014年第5期11卷 480-488页

作者： Sheng-ye Yan Xin-xing Xu Qing-Shan Liu School of Information and Control Nanjing University of Information Science and Technology School of Computer Engineering Nanyang Technological University

This paper proposes a new two-phase approach to robust text detection by integrating the visual appearance and the geometric reasoning rules. In the first phase, geometric rules are used to achieve a higher recall rate. Specifically, a robust stroke width transform(RSWT) feature is proposed to better recover the stroke width by additionally considering the cross of two strokes and the continuousness of the letter border. In the second phase, a classification scheme based on visual appearance features is used to reject the false alarms while keeping the recall rate. To learn a better classifier from multiple visual appearance features, a novel classification method called double soft multiple kernel learning(DS-MKL) is proposed. DS-MKL is motivated by a novel kernel margin perspective for multiple kernel learning and can effectively suppress the influence of noisy base kernels. Comprehensive experiments on the benchmark ICDAR2005 competition dataset demonstrate the effectiveness of the proposed two-phase text detection approach over the state-of-the-art approaches by a performance gain up to 4.4% in terms of F-measure.

关键词： Text detection geometric rule stroke width transform (SWT) support vector machine (SVM) multiple kernel learning (MKL)

The complex roles of m^(6)A modifications in neural stem cell proliferation, differentiation, and self-renewal and implications for memory and neurodegenerative diseases

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Neural Regeneration Research 2025年第6期20卷 1582-1598页

作者： Yanxi Li Jing Xue Yuejia Ma Ke ye Xue Zhao Fangliang Ge Feifei Zheng Lulu Liu Xu Gao Dayong Wang Qing Xia Department of Biochemistry and Molecular Biology College of Basic Medical SciencesHarbin Medical UniversityHarbinHeilongjiang ProvinceChina College of Basic Medical Sciences Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Basic Medical Institute Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Key Laboratory of Heilongjiang Province for Genetically Modified Animals Harbin Medical UniversityHarbinHeilongjiang ProvinceChina Translational Medicine Research and Cooperation Center of Northern China Heilongjiang Academy of Medical SciencesHarbinHeilongjiang ProvinceChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

N6-methyladenosine(m^(6)A), the most prevalent and conserved RNA modification in eukaryotic cells, profoundly influences virtually all aspects of mRNA metabolism. mRNA plays crucial roles in neural stem cell genesis and neural regeneration, where it is highly concentrated and actively involved in these processes. Changes in m^(6)A modification levels and the expression levels of related enzymatic proteins can lead to neurological dysfunction and contribute to the development of neurological diseases. Furthermore, the proliferation and differentiation of neural stem cells, as well as nerve regeneration, are intimately linked to memory function and neurodegenerative diseases. This paper presents a comprehensive review of the roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, as well as its implications in memory and neurodegenerative diseases. m^(6)A has demonstrated divergent effects on the proliferation and differentiation of neural stem cells. These observed contradictions may arise from the time-specific nature of m^(6)A and its differential impact on neural stem cells across various stages of development. Similarly, the diverse effects of m^(6)A on distinct types of memory could be attributed to the involvement of specific brain regions in memory formation and recall. Inconsistencies in m^(6)A levels across different models of neurodegenerative disease, particularly Alzheimer's disease and Parkinson's disease, suggest that these disparities are linked to variations in the affected brain regions. Notably, the opposing changes in m^(6)A levels observed in Parkinson's disease models exposed to manganese compared to normal Parkinson's disease models further underscore the complexity of m^(6)A's role in neurodegenerative processes. The roles of m^(6)A in neural stem cell proliferation, differentiation, and self-renewal, and its implications in memory and neurodegenerative diseases, appear contradictory. These inconsistencies may be a

关键词： Alzheimer's disease cell self-renewal central nervous system memory microglia nerve regeneration neurodegenerative diseases neurogenesis RNA methylation

A high resolution inversion method for fluid factor with dynamic dryrock V_(P)/V_(S) ratio squared

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Petroleum Science 2023年第5期20卷 2822-2834页

作者： Lin Zhou Jian-Ping Liao xing-ye Liu Pu Wang Ya-Nan Guo Jing-ye Li School of Earth Sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201HunanChina Key Laboratory of Earth Exploration and Information Technology of Ministry of Education College of GeophysicsChengdu University of TechnologyChengdu 610059SichuanChina Hunan Key Laboratory of Nonferrous Resources and Geological Hazards Exploration School of Geoscience and Info-PhysicsCentral South UniversityChangsha 410083HunanChina Exploration&Development Research Institute PetroChinaQinghai Oilfield CompanyDunhuang 736202GansuChina College of Geophysics China University of Petroleum(Beijing)Beijing 102249China

As an important indicator parameter of fluid identification,fluid factor has always been a concern for ***,when predicting Russell fluid factor or effective pore-fluid bulk modulus,it is necessary to introduce a new rock skeleton parameter which is the dry-rock VP/VS ratio squared(DVRS).In the process of fluid factor calculation or inversion,the existing methods take this parameter as a static constant,which has been estimated in advance,and then apply it to the fluid factor calculation and *** fluid identification analysis based on a portion of the Marmousi 2 model and numerical forward modeling test show that,taking the DVRS as a static constant will limit the identification ability of fluid factor and reduce the inversion *** solve the above problems,we proposed a new method to regard the DVRS as a dynamic variable varying with depth and lithology for the first time,then apply it to fluid factor calculation and ***,the exact Zoeppritz equations are rewritten into a new form containing the fluid factor and DVRS of upper and lower ***,the new equations are applied to the four parameters simultaneous inversion based on the generalized nonlinear inversion(GNI)*** testing results on a portion of the Marmousi 2 model and field data show that dynamic DVRS can significantly improve the fluid factor identification ability,effectively suppress *** synthetic and filed data tests also demonstrate that the GNI method based on Bayesian deterministic inversion(BDI)theory can successfully solve the above four parameter simultaneous inversion problem,and taking the dynamic DVRS as a target inversion parameter can effectively improve the inversion accuracy of fluid *** these results completely verified the feasibility and effectiveness of the proposed method.

关键词： Fluid factor Dry-rock V_(P)/V_(S)ratio squared(DVRS) Dynamic variable Multiple parameters simultaneous inversion Generalized nonlinear inversion(GNI)

Virome-wide analysis of histone modification mimicry motifs carried by viral proteins

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Virologica Sinica 2024年第5期39卷 793-801页

作者： Yang Xiao Shuofeng Yuan ye Qiu xing-Yi Ge Hunan Provincial Key Laboratory of Medical Virology Institute of Pathogen Biology and ImmunologyCollege of BiologyHunan UniversityChangsha410012China Department of Microbiology LKS Faculty of MedicineThe University of Hong KongHong Kong SAR999077China

Histone mimicry(HM)refers to the presence of short linear motifs in viral proteins that mimic critical regions of host histone *** motifs have the potential to interfere with host cell epigenome and counteract antiviral *** research shows that HM is critical for the pathogenesis and transmissibility of influenza virus and ***,the distribution,characteristics,and functions of HM in eukaryotic viruses remain ***,we developed a bioinformatic pipeline,Histone Motif Scan(HiScan),to identify HM motifs in viral proteins and predict their functions in *** analyzing 592,643 viral proteins using HiScan,we found that putative HM motifs were widely distributed in most viral *** animal viruses,the ratio of HM motifs between DNA viruses and RNA viruses was approximately 1.9:1,and viruses with smaller genomes had a higher density of HM ***,coronaviruses exhibited an uneven distribution of HM motifs,with betacoronaviruses(including most human pathogenic coronaviruses)harboring more HM motifs than other coronaviruses,primarily in the NSP3,S,and N *** summary,our virome-wide screening of HM motifs using HiScan revealed extensive but uneven distribution of HM motifs in most viral proteins,with a preference in DNA *** HM may play an important role in modulating viral pathogenicity and virus-host interactions,making it an attractive area of research in virology and antiviral medication.

关键词： Histone mimicry Viral proteins Histone modification Evolution Coronavirus

A BRANCH-AND-CUT APPROACH TO PORTFOLIO SELECTION WITH MARGINAL RISK CONTROL IN A LINEAR CONIC PROGRAMMING FRAMEWORK

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Journal of Systems Science and Systems Engineering 2013年第4期22卷 385-400页

作者： Zhibin DENG Yanqin BAI Shu-Cherng FANG ye TIAN Wenxun xing School of Management University of Chinese Academy of Sciences Industrial and Systems Engineering Department North Carolina State University Department of Mathematics Shanghai University School of Business Administration Southwestern University of Finance and Economics Department of Mathematical Sciences Tsinghua University

Marginal risk represents the risk contribution of an individual asset to the risk of the entire portfolio In this paper, we investigate the portfolio selection problem with direct marginal risk control in a linear conic programming framework. ＇The optimization model involved is a nonconvex quadratically constrained quadratic programming （QCQP） problem. We first transform the QCQP problem into a linear conic programming problem, and then approximate the problem by semidefinite programming （SDP） relaxation problems over some subrectangles. In order to improve the lower bounds obtained from the SDP relaxation problems, linear and quadratic polar cuts are introduced for designing a branch-and-cut algorithm, that may yield an e -optimal global solution （with respect to feasibility and optimality） in a finite number of iterations. By exploring the special structure of the SDP relaxation problems, an adaptive branch-and-cut rule is employed to speed up the computation. The proposed algorithm is tested and compared with a known method in the literature for portfolio selection problems with hundreds of assets and tens of marginal risk control constraints.

关键词： Portfolio selection linear conic programming branch-and-cut

Anticipation,anti-glaucoma drug treatment response and phenotype of a Chinese family with glaucoma caused by the Pro370Leu myocilin mutation

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International Journal of Ophthalmology(English edition) 2014年第1期7卷 44-50页

作者： Chun-Mei Li Yue-Hong Zhang Rong-Hua ye Chang-Xian Yi Yi-Min zhong Dan Cao xing Liu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen University First Municipal People's Hospital of Guangzhou

AIM: To describe the anticipation and anti-glaucoma drugs response of a Chinese family with juvenile-onset open angle glaucoma(JOAG) caused by the Pro370Leu myocilin(MYOC) mutation. ·METHODS: Fifteen members of a three-generation Chinese family with JOAG were recruited to this study. They all underwent ophthalmic common examinations. Patients suspected to have JOAG got an assessment of visual field and optical coherence tomography. Intraocular pressures(IOPs) of four patients were measured at 8,10,12,14,17 o’clock respectively after using anti-glaucoma drugs. Mutation screening of all MYOC gene coding exons of the participants was performed by using direct sequencing of PCR products. ·RESULTS: Clinical examinations and pedigree analysis revealed eight family members were suffered from JOAG. Apparent genetics anticipation phenomenon was observed in this family. Their clinical features included elevated IOP of 35-55mmHg,loss of visual field,thinning of retinal nerve fiber layer,and glaucomatous optic disc damage. Noticeably,their intraocular pressure levels could be controlled within normal range at 8 and 10 o’clock by anti-glaucoma drugs,but their IOPs would elevate >21mmHg after 12 o’clock. Seven patients received trabeculectomy produced thin-walled,pale,and saccate filtering blebs maintaining lower intraocular pressure efficiently. Mutation screening indentified aheterozygous C→T missense mutation in the MYOC gene at position 1 109 in exon 3,corresponding to a substitution of a highly conserved proline to leucine at codon 370 in the olfactomedin domain of MYOC. ·CONCLUSION: The clinical characteristics of JOAG in this family were 1) genetics anticipation; 2) high IOP; 3) temporay response to anti-glaucoma drugs; 4) filtering surgery produced thin-walled and saccate filtering blebs,helping maintain lower IOP.

关键词： phenotype anticipation anti-glaucoma drugs myocilin

Pingchan granule for depressive symptoms in parkinson’s disease:A randomized,double-blind,placebo-controlled trial

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Journal of Integrative Medicine 2021年第2期19卷 120-128页

作者： Si-chun Gu Jie Zhou Qing ye Can-xing Yuan Department of Neurology Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China

Background:Depression in Parkinson’s disease(dPD)is closely related to quality of *** studies have suggested that Pingchan Granule(PCG)might be effective for treating ***:This study determines the efficacy of PCG for depressive symptoms in Parkinson’s disease(PD).Design,setting,participants and interventions:This was a randomized,double-blind,placebo-controlled trial,conducted in Longhua Hospital,Shanghai,*** diagnosed with idiopathic PD and clinically significant depressive symptoms(defined by a 24-item Hamilton Rating Scale for Depression[HAM-D]score≥8)were included in this study,randomly assigned to PCG or placebo group in a 1:1 ratio and followed for 24 *** outcome measures:The primary outcome was the change from baseline to week 24 in HAM-D score among the set of patients who completed the study following the treatment protocol(per-protocol set).Secondary outcomes included changes in scores on the Unified Parkinson’s Disease Rating Scale(UPDRS)part 2(UPDRS-Ⅱ),UPDRS part 3(UPDRS-Ⅲ),Parkinson’s Disease Sleep Scale(PDSS)and Hamilton Rating Scale for Anxiety(HAM-A),between baseline and week ***:Eighty-six patients were enrolled,and 85 patients were included in the per-protocol ***-D scores decreased by an adjusted mean of 11.77(standard error SE 0.25)in the PCG group and 3.86(SE0.25)in the placebo group(between-group difference=7.91,95%confidence interval[7.22,8.80],P<0.001),in the multivariable linear *** in scores on the UPDRS-II,UPDRS-III,PDSS,and HAM-A scales were also ***:Treatment with PCG was well tolerated and improved depressive symptoms and motor and other non-motor symptoms in *** registration:Chinese Clinical Trial Register:ChiCTR-INR-17011949.

关键词： Pingchan granule Depression Parkinson’s disease Randomized controlled trial