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基于BERT和改进对抗训练的痛风病历分类方法

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计算机工程与设计 2024年第6期45卷 1668-1673页

作者：李胜煜王磊徐文畅贺玉伟李鑫德中国科学技术大学生物医学工程学院安徽合肥260026 中国科学院苏州生物医学工程技术研究所生物医学检验技术重点实验室江苏苏州215163 青岛大学附属医院山东省代谢性疾病重点实验室山东省免疫疾病与痛风临床医学研究中心山东青岛266000

为解决痛风电子病历文本稀疏性高、数据集小导致的分类任务准确率低问题,提出一种基于BERT预训练模型和改进对抗训练的痛风病历文本分类算法。使用中文生物医学语言预训练模型MC-BERT初始化病历文本,下接Text-CNN网络捕捉文本中不同长... 详细信息

为解决痛风电子病历文本稀疏性高、数据集小导致的分类任务准确率低问题,提出一种基于BERT预训练模型和改进对抗训练的痛风病历文本分类算法。使用中文生物医学语言预训练模型MC-BERT初始化病历文本,下接Text-CNN网络捕捉文本中不同长度的关键词信息,在模型训练过程中采用改进的对抗训练策略,在词嵌入中添加对抗性扰动提高模型的泛化性。实验结果表明,该算法可以提高中文痛风病历文本分类任务的精度,增强模型的鲁棒性。

关键词：痛风电子病历文本分类卷积神经网络对抗训练预训练模型词嵌入

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违约风险传染对中资美元债发行定价的影响

苏州大学学报（哲学社会科学版） 2024年第3期45卷 138-150页

作者：吴雄剑庞元晨李圣羽上海社会科学院世界经济研究所上海200023 安徽大学经济学院安徽230039 苏州国际发展集团有限公司江苏苏州215007

在中资美元债市场违约风险持续暴露的背景下,以2010—2022年的中资美元债为研究样本,考察同行业违约情况对中资美元债发行利差的影响。结果显示,债券发行前一年同行业每发生一次违约,则中资美元债发行利差会上升约4个BP;违约未偿金额每... 详细信息

在中资美元债市场违约风险持续暴露的背景下,以2010—2022年的中资美元债为研究样本,考察同行业违约情况对中资美元债发行利差的影响。结果显示,债券发行前一年同行业每发生一次违约,则中资美元债发行利差会上升约4个BP;违约未偿金额每上升1亿美元,则中资美元债发行利差会上升约1个BP。影响机制方面,同行业违约情况主要通过提高同行业其他企业的违约风险,从而增加中资美元债发行利差。分样本回归证明,对于原本违约风险更高的企业,比如非国有、非投资级以及无担保的债券,违约风险传染的效应更为显著,同行业违约情况对债券融资成本的影响更大。研究结论不仅丰富了违约风险传染的境外研究视角,也为境内监管部门把握外债风险情况提供了政策启示。

关键词：违约风险传染中资美元债发行定价

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新疆大气颗粒物污染时空演变及沙尘组分研究

中国环境科学 2024年第6期44卷 3012-3020页

作者：薛一波张小啸雷加强李生宇中国科学院新疆生态与地理研究所国家荒漠-绿洲生态建设工程技术研究中心新疆乌鲁木齐830011 中国科学院大学北京100049

利用2020~2022年新疆环境监测和同期气象要素数据,结合HYSPliT模式与PM_(2.5)/PM_(10)比值模型,探讨新疆颗粒物浓度的时空变化特征,并研究沙尘暴的主要输送路径、潜在源区及其对大气颗粒物浓度的贡献率.结果表明,新疆月均PM_(2.5)和PM_(... 详细信息

利用2020~2022年新疆环境监测和同期气象要素数据,结合HYSPliT模式与PM_(2.5)/PM_(10)比值模型,探讨新疆颗粒物浓度的时空变化特征,并研究沙尘暴的主要输送路径、潜在源区及其对大气颗粒物浓度的贡献率.结果表明,新疆月均PM_(2.5)和PM_(10)浓度变化呈波浪型分布,峰值出现在12~次年3月,最低值出现在6~8月;空间分布呈南高北低的特征,南疆年均PM_(2.5)和PM_(10)浓度分别为42~111,151~367μg/m^(3),北疆和东疆PM_(2.5)和PM_(10)浓度年均值相对较低,分别为10~62,21~110μg/m^(3)和28~50,100~145μg/m^(3);新疆69%的城市年均PM_(2.5)和PM_(10)浓度高于国家环境空气质量标准的二级浓度限值;大气PM_(2.5)和PM_(10)浓度呈显著正相关(R^(2)=0.84),春夏秋三季以PM_(10)污染为主,冬季以PM_(2.5)污染为主;PM_(10)是影响新疆空气质量的主要污染物,南疆AQI中PM_(10)贡献率为65%~96%,其次是东疆和北疆,分别为58%~65%和3%~41%;大气PM_(10)严重污染主要发生在春季,由PM_(10)造成南疆空气质量污染比重均在50%以上;塔克拉玛干沙漠是新疆沙尘暴灾害的主要沙源地;沙尘的高低空输送路径明显不同,高空传输主要源于沙漠腹地,而低空输沙源以沙漠东部为主;风蚀沙尘对大气PM_(10)和PM_(2.5)浓度的贡献率分别为85%和66%.

关键词：新疆 PM_(2.5) PM_(10) 时空变化沙尘组分空气质量数值模型

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多跨连续刚构桥合龙顶推方案优化

公路交通科技 2024年第8期41卷 137-145页

作者：胡志坚王智康李玉生武汉理工大学交通与物流工程学院湖北武汉430063 江西省交通投资集团有限责任公司江西南昌330025

为了能更好地减少多跨连续刚构桥成桥后期各个桥墩墩顶的纵桥向水平位移和结构附加内力,提出由中到边合龙依次顶推的优化方案,作出了相应的计算图示且推导了相关的理论计算公式,同时根据顶推力理论计算公式的需要,推导了变截面的主梁和... 详细信息

为了能更好地减少多跨连续刚构桥成桥后期各个桥墩墩顶的纵桥向水平位移和结构附加内力,提出由中到边合龙依次顶推的优化方案,作出了相应的计算图示且推导了相关的理论计算公式,同时根据顶推力理论计算公式的需要,推导了变截面的主梁和桥墩的抗弯惯性矩的理论计算公式,以某六跨连续刚构桥为例,建立有限元模型,通过理论计算公式和有限元模型分别计算了优化方案的顶推力数值并进行了对比分析,验证合龙优化方案顶推力理论计算公式的有效性,然后将由边到中的原合龙顶推方案和先中后边的优化合龙顶推方案作对比,验证合龙优化方案的合理性。结果表明:相较于原方案,使用优化方案虽然增加了顶推次数,但是其每次顶推力的数值较原方案中一次顶推力的数值都有大幅减少,从而能够有效地减少顶推处的局部应力水平;优化方案能更好地调控各个墩的变形,尤其是距离主梁中点较远的桥墩,因此优化方案对墩顶的纵向水平位移和墩底的弯矩改善效果更加明显;优化方案理论计算公式计算得到的顶推力数值相比于使用有限元模型推算的顶推力数值偏大,但总的来说相差不大,满足实际工程的要求;不同的顶推方案主要的影响是桥墩的变形与内力,顶推施工对成桥后主梁的收缩徐变以及线形的影响不大。

关键词：桥梁工程顶推方案优化数值模拟连续刚构桥墩变形

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基于冲击回转钻进的岩石强度随钻识别研究

岩土力学 2024年第3期45卷 857-866页

作者：刘勇斌张晓平李馨芳李德宏陈广军刘小波熊雪飞杨朗李玉生武汉大学土木建筑工程学院湖北武汉430072 中国铁建昆仑投资集团有限公司四川成都610040 四川蜀道高速公路集团有限公司四川成都610094 四川川黔高速公路有限公司四川成都646500 江西省交通投资集团有限责任公司江西南昌330025

在隧道掘进施工过程中,数字化钻孔过程监测(drillingprocessmonitoring,简称DPM)系统能够实时快速地获取岩石强度参数,及时指导现场开挖和支护作业。为实时获取隧道开挖掌子面前方的围岩强度,基于搭载于气动冲击回转钻机上的数字化DPM... 详细信息

在隧道掘进施工过程中,数字化钻孔过程监测(drillingprocessmonitoring,简称DPM)系统能够实时快速地获取岩石强度参数,及时指导现场开挖和支护作业。为实时获取隧道开挖掌子面前方的围岩强度,基于搭载于气动冲击回转钻机上的数字化DPM系统地开展现场原位数字钻进试验。通过对钻孔全过程的推进压力、回转压力、冲击压力以及钻杆位移等钻进参数进行实时监测、记录和分析,得到了不同钻孔过程的钻进参数特征,据此对各钻孔过程进行识别,并采用DPM时间序列分析方法分离出纯钻进过程钻进参数,结果表明:纯钻进过程的钻进深度随钻进时间呈分段线性变化;钻机工作压力随钻进时间的变化相对恒定,其对不同钻速段的钻速变化影响有限;同时,钻进速度随岩石强度增加而减小,并建立了岩石强度关于钻进速度的指数关系模型,用以指导工程实践。

关键词：冲击回转钻孔过程监测钻进参数饱和单轴抗压强度

Giant submucosal lipoma located in the descending colon: A case report and review of the literature

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World Journal of Gastroenterology 2007年第42期13卷 5664-5667页

作者： li Jiang li-sheng Jiang Fu-yu li Hui Ye Ning li Nan-sheng Cheng Yong Zhou The First Department of General Surgery West China Hospital of Sichuan University Chengdu610041 Sichuan Province China

Colonic lipoma is an uncommon tumor of the gastrointestinal tract. Most cases are asymptomatic, with a small tumor size, and do not need any special treatment. However, we encountered one patient with a giant submucosal lipoma, with a maximum diameter of 8.5 cm, which exhibited symptoms such as intermittent lower abdominal pain, changes in bowel habits with passage of fresh blood and mucus per rectum, abdominal distension, anorexia and weight loss. Unfortunately, the possibility of colonic malignancy could not be precluded and leffc hemicolectomy was planned. The exact diagnosis of this special case was accomplished by intraoperative pathology. In the end, local resection was performed instead of left hemicolectomy. To the best of our knowledge, colonic lipoma exceeding 8 cm in diameter has not been previously reported. We, therefore, present this case and discuss age and sex factors, clinical and histopathological findings, diagnostic methods and treatment by reviewing the available literature, to serve as a reminder that colonic lipoma can also exist in patients with significant symptoms. In addition, intraoperative pathology should be investigated in those doubtful cases, so as to guide the exact diagnosis and treatment plan.

关键词： Colon lipoma Age, Diagnosis Therapy

Brachial-ankle pulse wave velocity is an independent predictor of carotid artery atherosclerosis in the elderly

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Journal of Geriatric Cardiology 2010年第3期7卷 157-160页

作者： Jia-yue li yu-sheng Zhao Institute of Geriatric Cardiology Chinese PLA General HospitaLBeijing 100853 China

Objective Brachial-ankle pulse wave velocity （baPWV） is widely used as a simple noninvasive measure of arterial softness. The aim of this study was to evaluate the usefulness of baPWV as a predictor of the carotid artery atherosclerosis in the elderly. Methods A total of 721 elderly participants （mean ~ SD age, 70.3 -4- 5.6years） were enrolled in the current study. All participant underwent both baPWV measurement and B-mode ultrasound for the intima-media thickness. Carotid atherosclerosis （CAS） was defined as the present of carotid plaque or and/or intima media thickness for at least 1.1 mm. Results A multivariate logistic regression analysis reveals that age, sex, brachial-ankle pulse wave velocity, smoking and LDL-C level showed a significant correlation with the presence of CAS. The odds ratios of CAS associated with a 500cm/s increase of brachial-ankle pulse wave velocity were 2.378 [95% confidence interval, 1.36 to 4.00, P〈0.05], 3.733 [95% confidence interval, 1.729 to 8.058, P〈0.01], 4.438 [95% confidence interval, 1.659 to 11.803, P〈0.01]. The baPWV significantly correlated with IMT by bivariate correlation analysis （r=-0.39; p=0.001）. After adjusting for factors influencing, baPWV all the same correlated with IMT （r=-0.35; p=0.001）.Conclusion These results indicate that brachial-ankle PWV is an independent predictor of CAS in the *** also means that the direct measurement of arterial stiffness by this simple method may be of great help for the evaluation of carotid artherosclerosis, at least in the elderly

关键词： Aortic stiffness carotid arteriosclerosis pulse wave velocity

Source tectonic dynamics features of Jiuzhaigou Ms 7.0 earthquake in Sichuan Province,China

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Journal of Mountain Science 2018年第10期15卷 2266-2275页

作者： YI Shu-jian WU Chun-hao li yu-sheng HUANG Chao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese Academy of Science Beijing 100049China

On August 8, 2017, a Ms 7.0 earthquake occurred 5 km to the west of Jiuzhaigou National Park, causing 25 deaths and injuring 525. The objective of this study was to explore the seismogenic fault of the earthquake and tectonic dynamics of the source rupture. Field investigations, radon activity tests, remote sensing interpretations, and geophysical data analyses were carried out immediately after the earthquake. The Jiuzhaigou earthquake occurred at the intersection of the northern margin of the Minshan uplift belt and the south part of the Wenxian–Maqin fault in the south margin of the West Qinling geosyncline. There are two surface rupture zones trending northwest(NW), which are ground coseismic ruptures caused by concealed earthquake faults. The rupture on the southwest is the structure triggering the earthquake, along the Jiuzhaitiantang–Epicenter–Wuhuahai. The other one on the northeast(Shangsizhai–Zhongcha–Bimang) is a reactivation and extension of the secondary fault trending NW. The source rupture of this earthquake is a strike-slipshear fracture associated with the fault plane trending NW 331° and steeply dipping 75°, which is continuously expanding at both ends. The tectonic dynamics process of the source rupture is that the "Jiuzhaigou protrusion" is left-lateral sheared along the seismogenic fault in the NW direction. Finally, the Maqin fault and the arc fault system at the top of the "Wenxian protrusion" will be gradually broken through sometime in far future, as well as earthquaketriggered landslides will be further occurred along the narrow corridor between the seismogenic faults. The research results revealed the basic geological data and tectonic dynamic mechanism in this earthquake.

关键词： Jiuzhaigou Earthquake Surface rupture Tectonic dynamics Radon activity

6-O-Sulfated Modification of Natural Glycoalkaloids Chaconine and Solanine

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Chemical Research in Chinese Universities 2006年第2期22卷 189-192页

作者： ZHAO Ji-min li sheng-yu ZHOU Yi-fa ZHANG li-ping ZHOU Dao-wei School of life Sciences Northeast Normal University Changchun 130024P. R. China Department of Biology Changchun Normal CollegeChangchun 130032 P. R. China

Glycoalkaloids（GAS） have important biological and pharmaceutical activities, in order to study the relationship between the structures and the activities of carbohydrate chains, two natural glycoalkaloids, chaconine （compound 1 ） and solanine（ compound 2） , were isolated from potato stems and leaves（ Solanum tuberosum L. ）. The selective sulfation to the 6-hydroxy groups of chaeonine and solanine was carried out in a strategy by the use of protective groups. The 6-hydroxyl groups of the sugar chains in chaconine and solanine were protected with 4,4＇-dimethoxytrityl（DMT） while the other hydroxyl groups were acetylated. The protective group DMT was removed by using 0. 5% TFA in dichloromethane, The free 6-hydroxyl groups were sulfated by chlorosulfonic acid pyridine to give 6-O-sulfated products. After the acetyl groups were removed, the final products obtained were sulfated chaconine and sulfated solanine.^ 13C NMR spectra confirmed that chaconine and solanine were sulfated at O6 of the carbohydrate moiety.

关键词： Glycoalkaloids Chaconine Solanine Sulfation