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改进的多光谱聚合通道行人检测 被引量:4
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作者 彭志蓉 赵美蓉 +1 位作者 杨伟明 郑叶龙 《光电工程》 CAS CSCD 北大核心 2017年第9期882-887,共6页
针对外部环境的多变性和复杂性导致的单一波段下行人检测准确率较低的问题,提出了一种改进的基于可见和红外双波段聚合通道特征的行人检测算法。分别提取可见图像与红外图像的聚合通道特征;通过改变像素对比规则,采用自适应的阈值进行比... 针对外部环境的多变性和复杂性导致的单一波段下行人检测准确率较低的问题,提出了一种改进的基于可见和红外双波段聚合通道特征的行人检测算法。分别提取可见图像与红外图像的聚合通道特征;通过改变像素对比规则,采用自适应的阈值进行比较,将得到的改进的中心对称的局部二值模式特征添加到特征通道中;针对多光谱聚合通道特征设计了不同滤波器组进行滤波;训练分类器,实现多光谱下行人检测。实验表明,改进的局部二值模式特征能更好地描述红外图像中行人的对称性,中间滤波层丰富了候选特征池,算法在多种场景均能有效检测出行人,提高了行人检测精度,与利用多光谱聚合积分通道的检测工作相比,平均漏检率有所降低。 展开更多
关键词 行人检测 多光谱 局部二值模式 聚合通道 滤波器组
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Estrogenic activities of two synthetic pyrethroids and their metabolites 被引量:13
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作者 Meiqing Jin Ling Li +2 位作者 Chao Xu Yuezhong Wen meirong zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期290-296,共7页
Synthetic pyrethroids (SPs) are among the most common pesticides in current use, and so far, several SPs have been assessed for their potential estrogenicities by various methods. Previous studies have shown that th... Synthetic pyrethroids (SPs) are among the most common pesticides in current use, and so far, several SPs have been assessed for their potential estrogenicities by various methods. Previous studies have shown that the estrogenicities partly come from their metabolites. Although considerable information is available with respect to the metabolism and environmental degradation of SPs, little is known about the estrogenicities of the metabolites. In this study, permethrin (PM) and β-cypermethrin (CP), as well as their metabolites (3-phenoxybenzoic alcohol (PBCOH), 3-phenoxybenzaldehyde (PBCHO) and 3-phenoxybenzoic acid (PBCOOH) were evaluated for their estrogenic activities in the MCF-7 human breast carcinoma cell line. In the MCF-7 cell proliferation assay, PM and CP exhibited significant estrogenic activities at 10-7 mol/L, comparable to 17β-estradiol (E2) of 10-9 tool/L, with the relative proliferative effect ratios of 55.4% and 56.3%, respectively. The real-time quantitative polymerase chain reaction (qRT-PCR) results confirmed the estrogenicities of PM and CP with significant alteration of pS2 and ERα mRNA levels observed at 10-6 mol/L. For the three major metabolites, PBCOH and PBCOOH exhibited estrogenic activities in all assays, while no significant estrogenic responses was observed for PBCHO compared to the vehicle control. In particular, PBCOH had even slightly stronger estrogenic activity than its parent compounds, indicating that metabolism may be one of the reasons for the estrogenicities of the SPs. Given the widespread use of SPs, the toxicological effects of parent compounds and their metabolites should be taken into consideration in the risk assessment of SPs. 展开更多
关键词 PYRETHROIDS METABOLITES cell proliferation gene expression estrogenic activity
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An optical glass plane angle measuring system with photoelectric autocollimator 被引量:1
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作者 Yinguo Huang Yong Yang +3 位作者 Jiaqi Liang Zhengqing Miao meirong zhao Yelong Zheng 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2019年第2期71-76,共6页
Optical glass is the most widely used optical material.It is necessary to measure its geometric characteristic quickly and reliably to meet the quality of optical glass.A vision measuring system combining photoelectri... Optical glass is the most widely used optical material.It is necessary to measure its geometric characteristic quickly and reliably to meet the quality of optical glass.A vision measuring system combining photoelectric autocollimation system with high-precision rotary stage is designed to measure the parallelismand angle of optical glass plane.A novel method is proposed to overcome the difficulty ofmeasuring parallelismof optical glass.The model of parallelism and angle measurement is established and the feasibility is analyzed.The image processing algorithm combining Steger algorithm with the least square method is selected.The uncertainty of angle measurement system for angle measurement is 3.0″.The system can solve the problem of measuring the angle of optical glass with high precision and has important significance for optical system. 展开更多
关键词 OPTICAL GLASS PLANE ANGLE PARALLELISM PHOTOELECTRIC autocollimation system
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Polyhalogenated carbazoles induce hepatic metabolic disorders in mice via alteration in gut microbiota
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作者 Chenyang Ji Yunkai Luo +4 位作者 Jiawen Yang Yaoyao Dai Jiahui Miao Siqing Yue meirong zhao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第5期603-614,共12页
Polyhalogenated carbazoles(PHCZs)have been widely accepted as emerging pollutants,whereas their ecological and health risks remain uncertain.Herein,female and male Sprague-Dawley(SD)mice were treated with four typical... Polyhalogenated carbazoles(PHCZs)have been widely accepted as emerging pollutants,whereas their ecological and health risks remain uncertain.Herein,female and male Sprague-Dawley(SD)mice were treated with four typical PHCZs to investigate their negative consequences,along with alternations in gutmicrobiota to indicate underlyingmechanisms.In female mice,the relative liver weight ratio increased after four PHCZs exposure;2-bromocarbazole(2-BCZ)increased urine glucose level;3-bromocarbazole(3-BCZ)decreased the glucose and total cholesterol levels;3,6-dichlorocarbazole(3,6-DCCZ)decreased glucose level.The only disturbed biochemical index in male mice was the promoted alkaline phosphatase(ALP)level by 3,6-DCCZ.We also found that the differential blood biochemical indices were correlated with gut microbiota.3-BCZ and 3,6-DCCZ altered Bacteroidetes and Proteobacteria phyla in female and male mice,which were correlated with metabolic disorders.Our findings demonstrated the correlation between PHCZs induced potential hepatotoxicity andmetabolic disordersmay be due to their dioxin-like potentials and endocrine disrupting activities,and the gender differences might result from their estrogenic activities.Overall,data presented here can help to evaluate the ecological and health risks of PHCZs and reveal the underlying mechanisms. 展开更多
关键词 Polyhalogenated carbazoles LIVER Metabolic disorders Gut microbiota
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Anti-fertility effect of levonorgestrel and quinestrol in Brandt’s voles(Lasiopodomys brandtii) 被引量:6
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作者 meirong zhao Ming LIU +4 位作者 Dong LI Xinrong WAN Lyn A.HINDS Yanling WANG Zhibin ZHANG 《Integrative Zoology》 SCIE CSCD 2007年第4期260-268,共9页
The combination of levonorgestrel and quinestrol(EP-1)has been shown to have anti-fertility effects on several wild rodents,but the mechanism underlying these effects is poorly understood.We investigated the effects o... The combination of levonorgestrel and quinestrol(EP-1)has been shown to have anti-fertility effects on several wild rodents,but the mechanism underlying these effects is poorly understood.We investigated the effects of EP-1 and each of its components,levonorgestrel(P)and quinestrol(E),on the fertility of Brandt’s voles(Lasiopodomys brandtii)by using a gastric gavage method.The doses for EP-1,E and P were 1,0.34 and 0.66 mg/kg body weight,respectively.Male voles(n=98)were treated daily for 5 or 14 days,then the testes and epididymides were collected,weighed and examined histologically at 30(D30),60(D60)or 90(D90)days after the end of treatment.Four males were allowed to mate with normal females at D90.Female voles(n=75)were treated for 3 days and a further 3 days after a 7-day interval.The uteri and ovaries were weighed and examined histologically at 15(D15),30(D30)or 75(D75)days after the end of treatment.Each of three females were mated with fertile males at D30 and D75,respectively.Our results indicated that quinestrol(E)significantly decreased the sperm numbers in the testes as well as the weight of the testes and epididymides,with both of these tissues showing obvious structural abnormalities,and significantly reduced the litter size and the pup weight for females mated with males of the E treatment group.For female voles,treatment with E,P or EP-1 resulted in no marked influence on the fertility status.These data indicate that quinestrol(E)alone has a significant anti-fertility effect on male Brandt’s voles,but is ineffective in combination with levonorgestrel(P). 展开更多
关键词 Brandt’s voles(Lasiopodomys brandtii) fertility control LEVONORGESTREL quinestrol.
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