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A diagnosis model of parental care:How parents optimize their provisioning strategy in brood reduction?

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Current Zoology 2023年第4期69卷 385-392页

作者： Zhen-Qin Zhu Shu-Mei zi Li-Fang Gao Xiao-Dan Zhang Fang-Yuan liu qian Wang Bo Du School of Life Sciences Lanzhou UniversityLanzhou CityGansu Province 730000China College of Ecology Lanzhou UniversityLanzhou CityGansu Province 730000China

Altricial birds often display biased preferences in providing parental care for their dependent offspring,especially during food *** this process,such inflexible rules may result in provisioning *** demonstrate how parents optimize their provisioning strategies,we proposed a“diagnosis model”of parental care to posit that parents will undergo a diagnosis procedure to test whether selecting against some particular offspring based on phenotype is an optimal *** tested this model in an asynchronous hatching bird,the Azure-winged Magpie Cyanopica cyanus,based on 10 years of data about demography and parental provisioning *** their higher daily survival rates,core offspring(those hatched on the first day)merits an investment priority compared with their marginal brood mates(those hatched on later days).However,a marginal offspring also merited a priority if it displayed greater weight gain than the expected value at the early post-hatching *** could detect such a marginal offspring via a diagnosis strategy,in which they provisioned the brood at the diagnosis stage by delivering food to every nestling that begged,then biased food toward high-value nestlings at the subsequent decision stage by making a negative response to the begging of low-value *** this provisioning strategy,the growth performance of a nestling became a more reliable indicator of its investment value than its hatching order or competitive *** findings provide evidence for this“diagnosis model of parental care”wherein parents use a diagnosis method to optimize their provisioning strategy in brood reduction.

关键词： brood reduction parental care provisioning strategy weight gain

机器学习在颈椎疾病影像学诊断与预后预测中的应用综述

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医疗卫生装备 2024年第10期45卷 98-106页

作者：洪成坤付丽媛陈自谦福建中医药大学福总教学医院(第九〇〇医院)放射诊断科福州350025 福建中医药大学第一临床医学院福州350122 中国融通医疗健康集团莆田九十五医院医学影像科福建莆田351148

综述了机器学习在颈椎影像识别及处理、颈椎疾病诊断、颈椎疾病预后预测中的应用现状,分析了机器学习在颈椎疾病影像学诊断与预后预测中应用存在的问题和挑战,指出了开展更多多中心、大规模的研究,做到数据采集过程标准化,开发更具解释... 详细信息

综述了机器学习在颈椎影像识别及处理、颈椎疾病诊断、颈椎疾病预后预测中的应用现状,分析了机器学习在颈椎疾病影像学诊断与预后预测中应用存在的问题和挑战,指出了开展更多多中心、大规模的研究,做到数据采集过程标准化,开发更具解释性的模型,提高算法的可解释性和透明度等是未来机器学习应用于颈椎疾病影像学诊断与预后预测的发展方向。

关键词：机器学习颈椎疾病影像学诊断预后预测

Theoretical Study on the Rotational Spectra of Ar-D232S Complex

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Chinese Journal of Chemical Physics 2013年第6期26卷 656-660,I0003页

作者： Jin-ping Lei Yan-zi Zhou Dai-qian Xie Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic Chemistry Schoolof Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China

We report a theoretical study on the rotational spectra of Ar-D232S. The intermolecular po- tential energy surface was transformed from our latest ab initio three-dimensional potential of Ar-H232S. The rotational energy levels and wavefunctions of the complex were calcu- lated by using the radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm. The calculated rotational transition frequencies and structural parameters were found to be in good agreement with the available experimental values.

关键词： Rotational spectrum Van der Waals complex Molecular structure

Adaptive foreground and shadow segmentation using hidden conditional random fields

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 586-592页

作者： CHU Yi-ping YE Xiu-zi qian Jiang ZHANG Yin ZHANG San-yuan School of Computer Science State Key Lab. of CAD ＆ CG Zhejiang University Hangzhou 310027 China

Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is proposed, which models spatio-temporal constraints of video sequence. In order to improve the segmentation quality, the weights of spatio-temporal con- straints are adaptively updated by on-line learning for HCRFs. Shadows are the factors affecting segmentation quality. To separate foreground objects from the shadows they cast, linear transform for Gaussian distribution of the background is adopted to model the shadow. The experimental results demonstrated that the error ratio of our algorithm is reduced by 23% and 19% respectively, compared with the Gaussian mixture model (GMM) and spatio-temporal Markov random fields (MRFs).

关键词： Video segmentation Shadow elimination Hidden conditional random fields (HCRFs) On-line learning

A Composite Risk Measure Framework for Decision Making Under Uncertainty

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Journal of the Operations Research Society of China 2019年第1期7卷 43-68页

作者： Peng-Yu qian zi-Zhuo Wang Zai-Wen Wen Graduate School of Business Columbia UniversityNew YorkNY 10027USA Department of Industrial and Systems Engineering University of MinnesotaMinneapolisMN 55455USA Beijing International Center forMathematical Research PekingUniversityBeijing 100871China

In this paper,we present a unified framework for decision making under *** framework is based on the composite of two risk measures,where the inner risk measure accounts for the risk of decision if the exact distribution of uncertain model parameters were given,and the outer risk measure quantifies the risk that occurs when estimating the parameters of *** show that the model is tractable under mild *** framework is a generalization of several existing models,including stochastic programming,robust optimization,distributionally robust *** this framework,we study a few new models which imply probabilistic guarantees for solutions and yield less conservative results compared to traditional *** experiments are performed on portfolio selection problems to demonstrate the strength of our models.

关键词： Risk management Stochastic programming Portfolio management

3种现场混装炸药耦合装药炮孔壁峰值压力计算

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工程爆破 2024年第4期30卷 26-33页

作者：张贺何志伟郭子如谢守冬李萍丰胡前浩刘伟尹涛汪泉苏洪安徽理工大学化工与爆破学院安徽淮南232001 宏大爆破工程集团有限责任公司广州510623 安徽理工大学土木与建筑工程学院安徽淮南232001

炮孔壁峰值压力是产生炮孔周围应力场的源头,是造成孔壁附近岩石破坏的强动载荷。对于耦合装药,炮孔壁峰值压力是由爆轰波碰撞孔壁而生产的,通常这种碰撞是斜碰撞,并不是正碰撞。基于这样的物理事实,通过对现有耦合装药孔壁压力计算方... 详细信息

炮孔壁峰值压力是产生炮孔周围应力场的源头,是造成孔壁附近岩石破坏的强动载荷。对于耦合装药,炮孔壁峰值压力是由爆轰波碰撞孔壁而生产的,通常这种碰撞是斜碰撞,并不是正碰撞。基于这样的物理事实,通过对现有耦合装药孔壁压力计算方法行了评述,并提出斜碰撞的炮孔壁峰值压力计算方法。结果表明,爆轰冲击理论计算结果接近实测值和数值模拟值;引入斜入射系数可计算爆轰波斜入射时孔壁压力,爆轰波碰撞在炸药与孔壁的分界面上,在不同的入射角度下,作用在孔壁的压力是不同的。孔壁压力与炸药特性、岩体特性、爆轰波曲率半径、爆轰波入射角等有关。

关键词：峰值压力计算方法耦合装药爆轰波炮孔

新冠病毒非结构蛋白氨基酸变异与疾病严重程度的关系探究

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现代预防医学 2024年第11期51卷 2094-2099页

作者：边紫薇李东黄小丽徐映华王茜刘书洁胡贵方王海鹰南方医科大学公共卫生学院流行病学系

目的本研究旨在探讨严重急性呼吸综合征冠状病毒2型（severe acute respiratory syndrome corona coronavirus 2,SARS-CoV-2）非结构蛋白氨基酸变异是否与新型冠状病毒感染（corona virus disease 2019,COVID-19）疾病严重程度有关。方... 详细信息

目的本研究旨在探讨严重急性呼吸综合征冠状病毒2型（severe acute respiratory syndrome corona coronavirus 2,SARS-CoV-2）非结构蛋白氨基酸变异是否与新型冠状病毒感染（corona virus disease 2019,COVID-19）疾病严重程度有关。方法对全球共享流感数据倡议组织（GISAID）数据库得到的数据进行分析，筛选SARS-CoV-2序列中突变频率较高的非结构蛋白氨基酸突变。将患者结果分为轻症和重症，采用χ2检验比较组间基线特征，逻辑回归检验选择的突变与患者预后之间的关系。结果共纳入数据23 498例，其中男性11 444例（48.70%），女性12 054例（51.30%），中位数年龄[M（P25,P75）]为38（26,53）岁。男性新冠病毒感染重症率高于女性（χ2=226.564,P<0.001）；随着年龄增加（χ2=6 088.032,P<0.001），新冠病毒感染重症率增加。发病年份（χ2=1 604.070,P<0.001）、大洲（χ2=4 520.240,P<0.001）与新冠病毒感染严重程度显著相关。确定了SARS-CoV-2基因组中几种可能与新冠病毒感染严重程度相关的氨基酸变异，NSP4＿T492I（aOR=0.574, 95%CI:0.487～0.676）、NSP12＿G671S （aOR=0.657, 95%CI:0.458～0.941）、NSP6＿T77A（aOR=0.422, 95%CI:0.235～0.759）、NSP3＿P1228L （aOR=0.124, 95%CI:0.080～0.190）与新冠病毒感染重症呈负相关，而NSP12＿P323L （aOR=2.126, 95%CI:1.531～2.953）、NSP13＿P77L （aOR=1.923, 95%CI:1.115～2.369）、NSP14＿A394V（aOR=20.486, 95%CI:9.649～43.495）与新冠病毒感染重症呈正相关。结论 SARS-CoV-2非结构蛋白氨基酸变异可能与新冠病毒感染严重程度相关，需要进一步验证筛选可能与新冠病毒感染严重程度相关的非结构蛋白氨基酸变异。

关键词： SARS-CoV-2 疾病严重程度氨基酸变异非结构蛋白新冠病毒感染

Automatic recovery from resource exhaustion exceptions by collecting leaked resources

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第8期15卷 622-635页

作者： zi-ying DAI Xiao-guang MAO Li-qian CHEN Yan LEI College of Computer National University of Defense Technology Laboratory of Science and Technology on Integrated Logistics Support National University of Defense Technology Department of Computer Science University of California

Despite the availability of garbage collectors, programmers must manually manage non-memory finite system resources such as file descriptors. Resource leaks can gradually consume all available resources and cause programs to raise resource exhaustion exceptions. However, programmers commonly provide no effective recovery approach for resource exhaustion exceptions, which often causes programs to halt without completing their tasks. In this paper, we propose to automatically recover programs from resource exhaustion exceptions caused by resource leaks. We transform programs to catch resource exhaustion exceptions, collect leaked resources, and then retry the failure code. A resource collector is designed to identify leaked resources and safely release them. We implement our approach for Java programs. Experimental results show that our approach can successfully handle resource exhaustion exceptions caused by reported resource leaks and allow programs to complete their tasks with an average execution time increase of 2.52% and negligible bytecode size increase.

关键词： Failure avoidance Resource leaks Resource collection Exception handling Reliability

癌症相关性疼痛病人多维疼痛评估量表的构建及信效度检验

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中国疼痛医学杂志 2024年第3期30卷 196-204页

作者：郑振东黄明金毅罗素霞柳江路平汪子书庄莉余慧青仇晓霞刘波褚倩王昆刘勇任敬王杰军樊碧发中国人民解放军北部战区总医院肿瘤内科沈阳110000 中国人民解放军北部战区总医院疼痛科沈阳110000 中国人民解放军东部战区总医院疼痛科南京210002 河南省肿瘤医院肿瘤内科郑州450003 新疆维吾尔自治区人民医院肿瘤内科乌鲁木齐830001 新乡医学院第一附属医院肿瘤内科新乡453100 蚌埠医科大学第一附属医院肿瘤内科蚌埠233000 云南省肿瘤医院康复与姑息医学科昆明650106 重庆大学附属肿瘤医院老年肿瘤科重庆400030 上海交通大学医学院附属仁济医院肿瘤科及日间化疗中心上海200127 山东省肿瘤医院肿瘤内科济南250117 华中科技大学同济医学院附属同济医院肿瘤科武汉430030 天津市肿瘤医院疼痛科天津300060 徐州市中心医院肿瘤内科徐州221009 中日友好医院疼痛科北京100029

目的:本研究旨在构建适合癌症相关性疼痛(简称癌痛)病人的疼痛评估量表,并探索评估量表用于癌痛病人的信度和效度,以期为临床癌痛病人的管理提供更加综合全面且简便易行的评估工具。方法:基于国内癌痛领域的指导性规范、临床诊疗指南、... 详细信息

目的:本研究旨在构建适合癌症相关性疼痛(简称癌痛)病人的疼痛评估量表,并探索评估量表用于癌痛病人的信度和效度,以期为临床癌痛病人的管理提供更加综合全面且简便易行的评估工具。方法:基于国内癌痛领域的指导性规范、临床诊疗指南、专家共识等,本研究构建了癌痛病人评估量表初始条目池,采取德尔菲法选取我国癌痛领域的二十余名专家进行两轮咨询,统计咨询结果,确认纳入的条目,形成最终的多维疼痛评估量表(multi-dimensional brief test scale for pain,BTS)。经过两轮德尔菲法专家咨询,第一轮纳入21位专家,第二轮纳入10位专家,第一轮纳入19个评估维度,选取重要性评分≥4.5分且变异系数≤20%的7个评估维度,进行第二轮专家咨询。这7个评估维度和条目的重要性结果与第一轮一致,由此最终构建的BTS共包含7个评估维度,15个条目。选取2022年7月至2023年2月中国人民解放军北部战区总医院收治的癌痛病人,使用构建的BTS评估量表进行信效度检验。结果:共纳入166例病人,经过数据清洗,最终纳入分析的病人例数为138例。BTS的信度检测Cronbachα系数为0.78,效度检测的KMO值为0.80,具有较好的信度和效度。结论:构建的BTS条目共纳入7个评估维度,15个条目,具有较好的信度和效度,可在临床实践中推广应用于癌痛病人的疼痛评估。

关键词：癌症相关性疼痛疼痛评估德尔菲法