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Cervical cancer: Epidemiology, risk factors and screening

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Chinese Journal of Cancer Research 2020年第6期32卷 720-728页

作者： Shaokai Zhang huifeng xu Luyao Zhang Youlin Qiao Department of Cancer Epidemiology Affiliated Cancer Hospital of Zhengzhou University/Henan Cancer HospitalHenan Engineering Research Center of Cancer Prevention and ControlHenan International Joint Laboratory of Cancer PreventionZhengzhou 450008China Department of Epidemiology National Cancer CenterChinese Academy of Medical SciencesSchool of Population Medicine and Public HealthPeking Union Medical CollegeBeijing 100021China

Cervical cancer is one of the leading causes of cancer death among females worldwide and its behavior epidemiologically likes a venereal disease of low infectiousness. Early age at first intercourse and multiple sexual partners have been shown to exert strong effects on risk. The wide differences in the incidence among different countries also influenced by the introduction of screening. Although the general picture remains one of decreasing incidence and mortality, there are signs of an increasing cervical cancer risk probably due to changes in sexual behavior. Smoking and human papillomavirus(HPV) 16/18 are currently important issues in a concept of multifactorial, stepwise carcinogenesis at the cervix uteri. Therefore, society-based preventive and control measures, screening activities and HPV vaccination are recommended. Cervical cancer screening methods have evolved from cell morphology observation to molecular testing. High-risk HPV genotyping and liquid-based cytology are common methods which have been widely recommended and used worldwide. In future, accurate,cheap, fast and easy-to-use methods would be more popular. Artificial intelligence also shows to be promising in cervical cancer screening by integrating image recognition with big data technology. Meanwhile, China has achieved numerous breakthroughs in cervical cancer prevention and control which could be a great demonstration for other developing and resource-limited areas. In conclusion, although cervical cancer threatens female health, it could be the first cancer that would be eliminated by human beings with comprehensive preventive and control strategy.

关键词： Cervical cancer epidemiology risk factors screening

Mandatory CSR disclosure and analyst forecast properties:Evidence from a quasi-natural experiment in China

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China Journal of Accounting Research 2023年第2期16卷 23-46页

作者： Haina Shi Byron Y.Song huifeng xu Xiaodong xu School of Management Fudan UniversityShanghaiChina School of Business Hong Kong Baptist UniversityHong KongChina School of Accounting Guangdong University of Finance and EconomicsGuangzhouChina Antai College of Economics and Management Shanghai Jiaotong UniversityShanghaiChina

Based on a quasi-natural experiment that mandates a subset of listed firms to issue standalone corporate social responsibility(CSR)reports,we examine whether mandatory CSR disclosure improves analysts’information *** focus on two properties of analysts’earnings forecasts:forecast error and forecast *** find that the mandatory issuance of standalone CSR reports is related to less forecast error and less dispersed forecasts,and the effect varies with the firm-level information environment and provincelevel *** tests show that the improvement in forecast properties is mainly driven by CSR reports that i)are of high quality and ii)contain more long-term-oriented information than other CSR *** findings provide evidence that mandatory CSR disclosure plays an important informational role for financial analysts.

关键词： Mandatory disclosure Analyst forecast Corporate social responsibility

Magnetic beads-based multicolor colorimetric immunoassay for ultrasensitive detection of aflatoxin B_(1)

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Chinese Chemical Letters 2021年第4期32卷 1462-1465页

作者： Shan He Qitong Huang Ying Zhang Huifang Zhang huifeng xu xun Li Xiaoming Ma Department of Chemistry and Chemical Engineering Gannan Normal University.Ganzhou 341000China Scientific Research Center Gannan Medical UniversityGanzhou 341000China Fujian Key Laboratory of Integrative Medicine on Geriatrics Academy of Integrative MedicineFujian University of Traditional Chinese Medicine.Fuzhou 350100China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan UniversityChangsha 410082China

Aflatoxin B_(1)(AFB_(1))is one of the most toxic,mutagenic and carcinogenic mycotoxin,widely exists in contaminated food,grains and feedstuff *** this study,a novel magnetic beads multicolor colorimetric immunoassay(MBMCIA)based on Au@Ag nanorods(Au@Ag NRs)is proposed to visual detect ultralow concentration of AFB_(1)with high-resolution by the *** design the MBMCIA system,AFB_(1)-BSA conjugates were first coated on the surface of magnetic beads(MBs),then alkaline phosphatase(ALP)as a bridge between immunoassay a nd color reaction was used for catalytic hydrolysis of ascorbic acid-phosphate to generate reductive ascorbic ***,the yielded ascorbic acid could reduce silver ions to grow a silver coating on the surface of gold nanorods to generate Au@Ag NRs,which leads to the bule-shifted longitudinal absorption peak of Au NRs,accompanying with a series of perceptible color *** the optimal conditions,the proposed MBMCIA exhibited go od sensitivity and specificity for the detection of AFB_(1)with the detection limit as low as 5.7 pg/mL Meanwhile,the MBMCIA was also applied for the analysis of AFB_(1)in spiked wheat samples,the obtained recoveries range from 99.1%to 104.3%with relative standard deviation(RSD)less than 7.05%were *** proposed MBMCIA integrates separated,enriched,anti-interfe rence and signal read-out into one,which opens up a new avenue for an on-site visual food safety inspection or environmental monitoring.

关键词： Mycotoxin Aflatoxin B_1 Magnetic beads Immunoassay Multicolor Colorimetry

Transpiration Rates of Carex Meyeriana in Relation to Micrometerological Factors in a Mountain Valley Wetland

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Journal of Mountain Science 2009年第3期6卷 293-298页

作者： xu huifeng JIN Yanming DENG Wei xu Kezhang WANG Zhen College of Agriculture Jilin Agricultural University Changchun 130008 P.R. China. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610042 P.R. China. University of Nebraska-Board of Regents Lincoln NE 68503-1435 USA

In order to reveal transpiration rates of wetland plants and its relationships to micro-meterological factors in a mountain valley wetland, relative humidity, air temperature, leaf temperature, soil temperature, photo flux density and transpiration rates were measured once two hours in a Carex meyeriana wetland of the Changbai Mountain valley in dry (July) and wet (September) of 2003, respectively. Results showed that the tendency of "decreasing after increasing" was obvious in wet season. However, a relatively stable trend was observed for the transpiration in dry season.. Generally, the photon flux density of Carex meyeriana was higher in wet season than that in dry season. However, the variabilities of leaf temperature, air temperature and relative humidity were similar in both seasons. Higher transpiration rates of Carex meyeriana leaves were observed in July (varied from 40 to 150 mol·m-2·s-1) compared to those (varied from 7 to 14 mol·m-2·s-1) in September. Transpiration rates were significantly correlated with air temperature (P<0.01), leaf temperature (P<0.01), and wind speed (P<0.05), but correlationship between relative humidity and photo flux density was not significant (P<0.05).

关键词： Micrometerological factors transpiretion rates Carex meyeriana mountain valley wetland

一种新型零矢量的二三导通无刷直流电机直接转矩控制系统研究

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西安交通大学学报 2020年第4期54卷 85-92页

作者：徐会风苏少平杜庆诚西安交通大学电气工程学院西安710049

为了解决无刷直流电机转矩脉动幅值大的问题,提出一种新型零矢量的二三导通无刷直流电机直接转矩控制方法。该方法利用二相、三相交替导通的驱动方式,使用直接转矩控制方法,形成12个扇区,并定义了一种新型零矢量,改进了空间电压矢量选择... 详细信息

为了解决无刷直流电机转矩脉动幅值大的问题,提出一种新型零矢量的二三导通无刷直流电机直接转矩控制方法。该方法利用二相、三相交替导通的驱动方式,使用直接转矩控制方法,形成12个扇区,并定义了一种新型零矢量,改进了空间电压矢量选择表,降低了转矩脉动幅值。MATLAB仿真结果表明:当电机空载且以额定转速2000 r/min运行时,相比于传统零矢量,新型零矢量能使转矩脉动幅值降低约40.94%;当电机负载为4.3 N·m且以500 r/min低速运转时,相比于传统零矢量,新型零矢量能使转矩脉动幅值降低约47.40%;当电机负载为4.3 N·m且以额定转速2000 r/min高速运行时,新型零矢量使转矩脉动幅值降低约32.32%。不论电机运行于空载还是负载,低速还是高速,新型零矢量均能起到降低转矩脉动幅值的作用。该方法有效降低了电机的运行噪声,使电机运转更加平稳。新型零矢量可以应用于无刷直流电机的各种导通方式,对无刷直流电机应用于高性能场合具有重要意义。

关键词：新型零矢量二三导通直接转矩控制无刷直流电机转矩脉动

L^p(T,Σ,μ)(p≥1)型空间单位球面间的等距的表现和延拓(英文)

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南开大学学报（自然科学版） 2006年第6期39卷 75-84页

作者：侯志彬许会峰南开大学数学科学学院天津300071 保定师范专科学校数学与计算机系河北保定071000

给出了Lp型空间单位球面间的满等距表现定理,推广了关于lp型空间的相应定理.作为简单推论证明了相关的等距延拓定理.

关键词：等距映射严格凸测度空间重排算子

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乌拉苔草湿地土壤CO_2和CO的变化特征

东北林业大学学报 2006年第6期34卷 29-30页

作者：金研铭徐奇锋徐惠风吉林农业大学长春130118 河南省洛阳市西工区上寨小学

对乌拉苔草湿地生长季节内土壤CO2和CO的变化特征进行了模拟研究。结果表明:生长季节的乌拉苔草湿地土壤释放CO2,并消耗CO。化学反应CO+H2O→CO2+H2对于CO2和CO的动态变化起主要作用,CO2和CO之间存在显著的负相关。温度对CO2和CO体积分... 详细信息

对乌拉苔草湿地生长季节内土壤CO2和CO的变化特征进行了模拟研究。结果表明:生长季节的乌拉苔草湿地土壤释放CO2,并消耗CO。化学反应CO+H2O→CO2+H2对于CO2和CO的动态变化起主要作用,CO2和CO之间存在显著的负相关。温度对CO2和CO体积分数的影响存在一定差异,但差异不显著。

关键词： CO2 CO 乌拉苔草湿地土壤

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新型二维材料MXene在生物医学的应用

化学进展 2021年第5期33卷 752-766页

作者：许惠凤董永强朱希余丽双福建省中西医结合老年性疾病重点实验室福建中医药大学中西医结合研究院福州350122 食品安全分析检测技术教育部重点实验室福建省食品安全分析检测技术省级重点实验室福州大学化学学院福州350108 福建农林大学生命科学学院福州350002 福建中医药大学药学院福州350122

MXene是一类新型的二维过渡金属碳化物和氮化物的总称,通式为M_(n+1)X_(n)T_(x)(n=1~3),其中M为前过渡金属元素,X为碳或氮元素,T指键合在该材料表面的氟基、羟基或氧基等活性官能团。该类材料具有超薄的结构和出色的物理化学(电子、光... 详细信息

MXene是一类新型的二维过渡金属碳化物和氮化物的总称,通式为M_(n+1)X_(n)T_(x)(n=1~3),其中M为前过渡金属元素,X为碳或氮元素,T指键合在该材料表面的氟基、羟基或氧基等活性官能团。该类材料具有超薄的结构和出色的物理化学(电子、光学、磁性等)特性,从而吸引了各领域研究人员的广泛兴趣。目前,MXene在生物医学领域的应用逐渐拓展。这主要是由于其大的表面积和在近红外区域的强吸收,加之其可以通过容易的表面修饰与多种分子或者纳米颗粒结合。在这篇综述中,我们总结了MXene在生物医学应用中的最新进展。文章首先介绍MXene的相关制备方法和表面改性手段;之后重点围绕其独特的理化性质,依次介绍该材料在抗菌材料、生物成像、肿瘤诊断治疗和生物传感等生物医学领域中的应用进展;文章最后总结讨论了MXene在生物医学应用方面面临的挑战和新机遇。预期超薄MXene及精巧设计的纳米复合物将成为多种生物医学应用的最有吸引力的生物相容性无机纳米平台之一。

关键词： MXene 抗菌生物成像肿瘤诊断治疗生物传感

L1模解卷方法的有效性及其在地下目标声学探测中的应用研究

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仪器仪表学报 2008年第4期29卷 836-840页

作者：徐慧峰钱彦岭温激鸿邱静刘宝华国防科技大学机电工程与自动化学院长沙410073 海军飞行学院教研部葫芦岛125001

L1模解卷方法是提高声学探测系统时间分辨率的一种常用方法。为了评估该方法在地下目标声学探测中的有效性及极限性能,定义了一系列评价指标,对其进行了仿真和实际应用分析。研究发现,L1模解卷方法只在目标函数加权系数的一定取值范围... 详细信息

L1模解卷方法是提高声学探测系统时间分辨率的一种常用方法。为了评估该方法在地下目标声学探测中的有效性及极限性能,定义了一系列评价指标,对其进行了仿真和实际应用分析。研究发现,L1模解卷方法只在目标函数加权系数的一定取值范围内有效,并且存在最优值,其最佳效果取决于输出信号的信噪比。同时,针对实际探测系统,论文给出了一种优选加权系数的方法。应用表明,该方法是行之有效的。

关键词：地下目标声学探测 L1模解卷有效性