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Prevalence of Metabolic Obese Normal Weight and Related Risk Factors in South China
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作者 Xuehua LUO Zien LIANG +7 位作者 Yan LI Qingbin WU Zhiqiang PAN Yuqing LIANG Lingyu LI Juanjuan MAI Huijun XIE Li HAN 《Medicinal Plant》 CAS 2021年第2期74-78,共5页
[Objectives]Metabolic obese normal weight(MONW)is becoming one of the pubic problems which are threatening human health.Whereas,MONW was facing a great challenge for limited attention,especially for the female in Chin... [Objectives]Metabolic obese normal weight(MONW)is becoming one of the pubic problems which are threatening human health.Whereas,MONW was facing a great challenge for limited attention,especially for the female in China.The aim of this research was to estimate the prevalence of MONW and its related risk components in South China.[Methods]A community-based cross-sectional study was performed on 3349 residents aged 18-93 years in The First Affiliated Hospital of Jinan University,Guangzhou,China,in 2019.Data was collected by physical examination data which included physical measurements and laboratory examinations.[Results]In all subjects,55%were females(M/F=1509/1840).The prevalence of MONW was 16.09%(0.04%for male,16.05%for female,P<0.001).The prevalence increased significantly with increasing age in both genders(P<0.001).The binary logistic regression analysis shows that among the risk factors with MONW,age,BMI,gender,systolic pressure,hypertension[Male:ORs=2.56,95%CI(1.23,5.32);Female:ORs=2.88,95%CI(1.76,4.71)]and hypertriglyceridemia[Male:ORs=3.23,95%CI(1.67,6.19);Female:ORs=2.57,95%CI(1.64,4.03)]were found to be statistically significant.The level of ALT in MONW group was(27.88±15.85)in male and(24.33±15.75)in female,which were significantly higher than those in the non-MetS group.[Conclusions]The prevalence of MONW was pretty high.We considered MONW be significantly associated with the increase of ALT.Female gender,advanced age,and elevated ALT were independent risk factors for MONW.It was high time that the government should raise the public attention toward metabolic function in normal weight population.Effective prevention and treatment strategies for MONW and its risk factors should be developed targeting different ages and genders. 展开更多
关键词 Metabolic Obese normal weight PREVALENCE Related risk factor
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Therapeutic Effect of Lifestyle Intervention Combined with Drug Therapy on Patients with Normal Weight Polycystic Ovary Syndrome
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作者 ZHANG Yan XU Qiongkai +1 位作者 HUANG Shaozhen ZHOU Huanlian 《外文科技期刊数据库(文摘版)医药卫生》 2021年第7期042-043,共4页
Objective: to investigate the clinical efficacy and lifestyle of clomiphene citrate in the treatment of normal weight polycystic ovary syndrome. Methods: from June 2017 to June 2018, 76 patients with normal weight pol... Objective: to investigate the clinical efficacy and lifestyle of clomiphene citrate in the treatment of normal weight polycystic ovary syndrome. Methods: from June 2017 to June 2018, 76 patients with normal weight polycystic ovary syndrome diagnosed and treated in our hospital were investigated and analyzed. All patients were randomly divided into experimental group and control group. The control group was given clomiphene citrate to induce ovulation, and the experimental group was given lifestyle intervention therapy on the basis of the control group. The therapeutic effects of the two groups were compared. Results: the experimental group was significantly higher than the control group, and the difference was statistically significant (P < 0.05) after statistical calculation of the treatment effect of the patient. The indexes of luteinizing hormone experimental group, endometrial thickness, ovarian volume and the like of the patient were all thicker than those of the control group. The comparison results of the two data groups showed that there was a difference (P < 0.05). Conclusion: lifestyle intervention combined with drug-induced ovulation in patients with normal weight polycystic ovary syndrome can increase the endometrial thickness of patients, which is of great significance for clinical promotion and application. 展开更多
关键词 polycystic ovary syndrome with normal weight clomiphene citrate inducing ovulation lifestyle inte
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Process Capability Analysis of Delivering Neonatal Care with Normal Weight (Case Study of Neonatal Weight Data at a Maternity Clinic in Banjarmasin)
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作者 Dewi Anggraini 《Journal of Life Sciences》 2011年第12期996-1002,共7页
Statistical Quality Control (SQC) is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to as... Statistical Quality Control (SQC) is used to analyze and monitor quality characteristic measurements of normal neonatal weight in a maternity clinic in Banjarmasin in this paper. The objective of this study is to assist medical practitioners in observing pregnant women to deliver their babies with normal weight. It is also assumed that pregnant women who delivered their babies in the clinic have been monitored during their nine-month pregnancy. Thus, they can manage their own pregnancy to deliver normal weight babies. The use of Statistical Process Control (SPC) tools, such as frequency histogram, probability plot, and the implementation of Shewhart, R, and S control charts as primary techniques, are presented to display the monitoring aspects of the process. In addition, Process Capability Analysis (PCA) is performed to ensure that the process outcomes are capable of meeting certain requirements or specifications. The Process Capability Ratio (PCR) for the process is also presented. This analysis is an essential part of an overall quality improvement program. 展开更多
关键词 Process capability analysis Shewhart control chart R-chart normal neonatal weight.
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Composition Cesàro Operator on the Normal Weight Zygmund Space in High Dimensions 被引量:1
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作者 Si XU Xuejun ZHANG Shenlian LI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2021年第1期69-84,共16页
Let n>1 and B be the unit ball in n dimensions complex space C^(n).Suppose thatφis a holomorphic self-map of B andψ∈H(B)withψ(0)=0.A kind of integral operator,composition Cesàro operator,is defined by T_(... Let n>1 and B be the unit ball in n dimensions complex space C^(n).Suppose thatφis a holomorphic self-map of B andψ∈H(B)withψ(0)=0.A kind of integral operator,composition Cesàro operator,is defined by T_(φ)ψ(f)(z)=∫^(1)0f[φ(tz)]Rψ(tz)dt/t,f∈(B)z∈B.In this paper,the authors characterize the conditions that the composition Cesàro operator T_φ,ψis bounded or compact on the normal weight Zygmund space Z_μ(B).At the same time,the sufficient and necessary conditions for all cases are given. 展开更多
关键词 normal weight Zygmund space Composition Cesàro operator Boundedness and compactness
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Composition operators on the normal weight Dirichlet type space in the unit disc
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作者 Xuejun ZHANG Min ZHOU Hongxin CHEN 《Frontiers of Mathematics in China》 SCIE CSCD 2022年第4期545-552,共8页
Let p>0 andνbe a normal function on[0,1).In this paper,several equivalent characterizations are given for which composition operators are bounded or compact on the normal weight Dirichlet type space D_(ν)^(p)(D)i... Let p>0 andνbe a normal function on[0,1).In this paper,several equivalent characterizations are given for which composition operators are bounded or compact on the normal weight Dirichlet type space D_(ν)^(p)(D)in the unit disc. 展开更多
关键词 Composition operator normal weight Dirichlet type space BOUNDEDNESS COMPACTNESS unit disc
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Dombi-Normalized Weighted Bonferroni Mean Operators with Novel Multiple-Valued Complex Neutrosophic Uncertain Linguistic Sets and Their Application in Decision Making 被引量:1
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作者 Tahir Mahmood Zeeshan Ali +1 位作者 Dulyawit Prangchumpol Thammarat Panityakul 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第3期1587-1623,共37页
Although fuzzy set concepts have evolved,neutrosophic sets are attractingmore attention due to the greater power of the structure of neutrosophic sets.The ability to account for components that are true,false or neith... Although fuzzy set concepts have evolved,neutrosophic sets are attractingmore attention due to the greater power of the structure of neutrosophic sets.The ability to account for components that are true,false or neither true nor false is useful in the resolution of real-life problems.However,simultaneous variations render neutrosophic sets unsuitable in specific circumstances.To enable the management of these sorts of issues,we combine the principle of multi-valued neutrosophic uncertain linguistic sets and complex fuzzy sets to develop the principle of multivalued complex neutrosophic uncertain linguistic sets.Multi-valued complex neutrosophic uncertain linguistic sets can contain grades of truth,abstinence,and falsity,and uncertain linguistic terms,which are expressed as complex numbers whose real and imaginary parts are limited to the unit interval.Some important Dombi laws are elaborated along with Bonferroni mean operators,which offer a flexible general structure with modifiable factors.Bonferroni means aggregation operators perform a significant role in conveying the magnitude level of options and characteristics.To determine relationships among any number of attributes,we develop multi-valued complex neutrosophic uncertain linguistic Dombi-normalized weighted Bonferroni mean operators and discuss their important properties with some special cases.By using these laws,we can deploy themulti-attribute decisionmaking(MADM)technique using the novel principle of multi-valued complex neutrosophic uncertain linguistic sets.To determine the power and flexibility of the elaborated approach,we resolve some numerical examples based on the proposed operator.Finally,the work is validated with the help of comparative analysis,a discussion of its advantages,and geometric expressions of the elaborated theories. 展开更多
关键词 Multi-valued complex neutrosophic uncertain linguistic sets Dombi normalized weighted Bonferroni mean operators multi-attribute decision-making methods
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Spectrum of Normal Weighted Composition Operators on the Fock Space Over C^N 被引量:4
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作者 Li Xia FENG Lian Kuo ZHAO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2019年第9期1563-1572,共10页
By using commutative C*-algebra techniques, spectrum and essential spectrum of normal weighted composition operators on the Fock space over CN are completely characterized. As an application, spectrum of self-adjoint ... By using commutative C*-algebra techniques, spectrum and essential spectrum of normal weighted composition operators on the Fock space over CN are completely characterized. As an application, spectrum of self-adjoint weighted composition operators on the Fock space are obtained also. 展开更多
关键词 FOCK space weigh TED composition OPERATOR normal SPECTRUM
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A Class of Normal Weighted Composition Operators on the Fock Space of C^n 被引量:3
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作者 Lian Kuo ZHAO 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2015年第11期1789-1797,共9页
This paper characterizes a class of normal weighted composition operators and their spectrum on the Fock space of Cn.
关键词 Fock space weighted composition operator normal SPECTRUM
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Metabolically obese normal-weight children
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作者 Fernando Guerrero-Romero Martha Rodríguez-Moran 《World Journal of Clinical Pediatrics》 2012年第4期37-39,共3页
Non-obese children with elevated serum insulin levels and metabolic disorders such as,hyperglycemia,hypertension,and/or hypertriglyceridemia are a subset of children in high risk of developing cardiovascular disease l... Non-obese children with elevated serum insulin levels and metabolic disorders such as,hyperglycemia,hypertension,and/or hypertriglyceridemia are a subset of children in high risk of developing cardiovascular disease later in life.Since usually the health policies for the prevention of the obesity associated disorders in children are based on the screening focused on the obese,frequently the metabolically obese normalweight(MONW) children are not identified in primary care setting.Given that characterization of the MONW children is an important public health issue,and that a large amount of resources might be unnecessarily used in the screening of metabolic risk of nonobese children; we review data regarding criteria for the early recognition of this subset of children in high risk of developing cardiovascular disease.Results of our review suggests that the presence of family history of type 2 diabetes and/or hypertension,the elevated percentage of body fat,and the high birth-weight should be taken into account as criteria of high cardiovascular risk,irrespective of obesity. 展开更多
关键词 Children normal-weight CARDIOVASCULAR risk factors Screening OBESITY
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东北三省干旱时空特征及其对植被覆盖变化的影响
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作者 李颖 马双 +4 位作者 徐菀笛 马霄雪 刘自颖 彭飞 常艺琼 《生态学报》 北大核心 2026年第5期2701-2723,共23页
东北三省是中国重要的农业生产和森林覆盖区,在气候变化背景下该区域暖干化趋势明显,生态安全受干旱胁迫的风险增加,改善干旱事件监测能力、量化干旱对植被的影响是减轻区域灾害、保障生态安全的重要措施之一。基于东北三省119年的气温... 东北三省是中国重要的农业生产和森林覆盖区,在气候变化背景下该区域暖干化趋势明显,生态安全受干旱胁迫的风险增加,改善干旱事件监测能力、量化干旱对植被的影响是减轻区域灾害、保障生态安全的重要措施之一。基于东北三省119年的气温、降水、实际水汽压栅格数据,从气象干旱和大气干旱两个角度表征干旱,并分析不同时间尺度干旱的特征,总结干旱发生规律;结合34年的植被指数,利用相关性分析和多尺度地理加权回归模型,分析不同时间尺度干旱对植被覆盖的影响程度。研究结果表明,东北三省的气象干旱在9月表现出最明显的干旱化趋势,而大气干旱趋势在5月最明显。辽宁气象干旱强弱特征与吉林、黑龙江相反,且显著变干的地区多出现在气象干旱较弱地区。大气干旱的强弱基本为辽宁>吉林>黑龙江,显著变干的地区多出现在大气干旱较强地区。大气干旱比气象干旱对植被覆盖的影响更强烈;其中,松嫩平原是大气干旱显著影响的地区,植被覆盖状况较低,大气干旱在该地区显著变干,因此松嫩平原地区应注意抗旱减灾。 展开更多
关键词 气象干旱 大气干旱 归一化植被指数 相关分析 多尺度地理加权回归
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结合图论Normalized Cut方法的彩色图像分割研究 被引量:1
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作者 任爱红 白婷婷 《甘肃科学学报》 2012年第3期147-150,共4页
归一化彩色图像分割中高斯核函数的参数选择直接影响到分割效果.为了寻找无参数的权值计算方法,提出将彩色图像中的像素点视为RGB空间的三维向量,使用向量的方向和幅值差异来衡量像素点的相似性,再使用Normalized Cut方法进行分割.实验... 归一化彩色图像分割中高斯核函数的参数选择直接影响到分割效果.为了寻找无参数的权值计算方法,提出将彩色图像中的像素点视为RGB空间的三维向量,使用向量的方向和幅值差异来衡量像素点的相似性,再使用Normalized Cut方法进行分割.实验结果表明,该方法能有效区分不同的颜色信息,计算复杂度不大,兼顾了算法的运算时间及分割效果,对不同的彩色图像均能得到准确的分割结果. 展开更多
关键词 图论 权值函数 归一割 彩色图像分割
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基于点云曲面拟合的桥梁拉索成像位姿精确估计方法
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作者 彭帝 朱英硕 +3 位作者 夏晓华 邓一豪 贾昕宇 苗龙龙 《公路工程》 2026年第1期83-89,134,共8页
桥梁拉索成像位姿估计是利用图像实现拉索表面缺陷几何参数测量的前提条件,其位姿估计精度决定了尺寸测量的准确性。针对现有方法存在的精度不足问题,提出了一种基于点云曲面拟合的拉索成像位姿精确估计方法。该方法首先利用直通滤波算... 桥梁拉索成像位姿估计是利用图像实现拉索表面缺陷几何参数测量的前提条件,其位姿估计精度决定了尺寸测量的准确性。针对现有方法存在的精度不足问题,提出了一种基于点云曲面拟合的拉索成像位姿精确估计方法。该方法首先利用直通滤波算法获得深度相机采集的圆柱表面单侧点云,然后通过基于RANSAC算法的法线加权拟合算法对圆柱曲面进行准确重建,剔除点云异常数据对曲面拟合造成的不利影响,最后结合重建的曲面方程实现圆柱成像位姿估计。试验结果表明,该方法实现了0.38°以内的角度误差和0.43 mm以内的距离误差,与ICP点云配准和RANSAC拟合方法等当前先进的位姿估计方法相比具有更高的精度。此方法为基于机器视觉的圆柱表面缺陷几何参数测量奠定了基础。 展开更多
关键词 桥梁拉索 点云 圆柱拟合 法线加权 位姿估计
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汽车后排大腿角模型化研究及应用
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作者 李忠良 《中国汽车(中英文对照)》 2026年第3期178-182,共5页
针对后排大腿角A57,本文构建计算模型,明确其影响因子及权重,提出案例阐述应用价值。首先,定义人体坐姿相关参数,以SAE人体模型建立坐标系,推导大腿角A57计算模型,其影响参数包括下肢长度、踝角、脚踏平面角和坐高。其次,选择DOE回归分... 针对后排大腿角A57,本文构建计算模型,明确其影响因子及权重,提出案例阐述应用价值。首先,定义人体坐姿相关参数,以SAE人体模型建立坐标系,推导大腿角A57计算模型,其影响参数包括下肢长度、踝角、脚踏平面角和坐高。其次,选择DOE回归分析确定关键影响因素,结果表明踝角、坐高、下肢长度对A57影响显著,脚踏平面角影响较小,且下肢长度与A57呈正相关,其余呈负相关。最后,通过实例说明该模型在舒适性设计基准人体的确立、人体坐姿舒适性的评估以及个性化座椅设计方面的应用价值,为座椅设计提供参考与技术支撑。 展开更多
关键词 后排大腿角 模型化研究 DOE回归分析 归一化权重 舒适性设计
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基于灰色直觉模糊综合评价法的复杂冲压件工艺方案评估
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作者 肖振泉 伍建伟 《锻压技术》 北大核心 2026年第2期37-46,共10页
为了解决复杂冲压件工艺方案评估的灰色性、模糊性和随机性问题,提出了一种灰色直觉模糊综合评价法对冲压工艺方案进行评估。首先,根据冲压生产影响因素和评估习惯,确定指标体系和等级。然后,运用直觉模糊层次分析法计算指标权重,并引... 为了解决复杂冲压件工艺方案评估的灰色性、模糊性和随机性问题,提出了一种灰色直觉模糊综合评价法对冲压工艺方案进行评估。首先,根据冲压生产影响因素和评估习惯,确定指标体系和等级。然后,运用直觉模糊层次分析法计算指标权重,并引入“惩罚型”变权向量进行修正;结合直觉模糊理论和正态云构建直觉正态云,计算评估指标对各等级的隶属度,同时以灰度表征隶属度的可信度;运用直觉模糊算子对权重和隶属度进行综合处理,得到定量评估结果。最后,对某零件冲压工艺方案进行评估验证。结果表明:所提方法评估结果与实际相符;与传统方法相比,所提方法不仅可以得到定量评估结果,还可以给出相应的评估精确度,优选出的冲压工艺方案能够满足零件生产要求。 展开更多
关键词 冲压工艺方案 灰色直觉模糊综合评价法 直觉模糊层次分析法 变权 直觉正态云
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关于超高分子量聚乙烯项目建设的发展及政策符合性论述
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作者 许贤文 张玉琪 《山东化工》 2026年第1期109-113,共5页
超高分子量聚乙烯(UHMWPE)作为乙烯下游加工的一类优异产品,因其优良的性能被广泛应用,目前处于快速发展阶段。在特定地区,项目核准政策的解读存在一定程度的分歧,本文介绍了UHMWPE产品的特性与应用、建设项目现状,并分析论述了UHMWPE... 超高分子量聚乙烯(UHMWPE)作为乙烯下游加工的一类优异产品,因其优良的性能被广泛应用,目前处于快速发展阶段。在特定地区,项目核准政策的解读存在一定程度的分歧,本文介绍了UHMWPE产品的特性与应用、建设项目现状,并分析论述了UHMWPE项目建设的政策适宜性,以供同行类似项目进行借鉴和参考。 展开更多
关键词 超高分子量聚乙烯 UHMWPE 技术性能 规范性 符合性
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Diabetes in adolescents without obesity in India:An underrecognized phenotype
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作者 Rashi Agrawal Akhila Bhandarkar Nitin Kapoor 《World Journal of Clinical Pediatrics》 2025年第4期537-541,共5页
Adolescent type 2 diabetes mellitus(T2DM)is on the rise in India and is commonly attributed to co-existence of overweight and obesity in adolescents.In this line,a study by Maheshwari et al titled‘Prevalence of obesi... Adolescent type 2 diabetes mellitus(T2DM)is on the rise in India and is commonly attributed to co-existence of overweight and obesity in adolescents.In this line,a study by Maheshwari et al titled‘Prevalence of obesity,determinants,and its association with hyperglycaemia among community dwelling older adolescents in India’concluded that overweight,obesity,socioeconomic factors and higher education status were responsible for hyperglycemia in adolescents aged 15-19 years in India.We highlight that there is a significant prevalence of T2DM even in normal body mass index(BMI)and below normal BMI subjects,as mentioned in their study.There is a high prevalence of normal weight obesity in Indian adolescents which often gets missed due to a large population with normal BMI in the country.In this letter,we analyze the importance of measurement of central adiposity beyond routine BMI measurements. 展开更多
关键词 normal weight obesity Adolescents Body mass index Metabolic syndrome Body composition Visceral fat Cardiometabolic risk
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Dietary antioxidant index and cardiometabolic risks in normal-weight individuals:Evidence from the National Health and Nutrition Examination Survey
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作者 Ting Xue Xiuying He +5 位作者 Yiyang Xu Ji Fang Min Lin Lihua Cai Tian Zheng Li Li 《Asia Pacific Journal of Clinical Nutrition》 2025年第6期941-951,共11页
Background and Objectives:Caloric restriction is the most popular dietary intervention for preventing metabolicdisorders.However,its benefits are limited in normal-weight individuals.This study aimed to examine the as... Background and Objectives:Caloric restriction is the most popular dietary intervention for preventing metabolicdisorders.However,its benefits are limited in normal-weight individuals.This study aimed to examine the associationbetween composite dietary antioxidant index(CDAI)and metabolically unhealthy normal weight(MUNW),as well as the relationship between CDAI and cardiometabolic mortality among normal-weight individuals,in order to provide personalized dietary recommendations.Methods and Study Design:This study consistedof two parts:(1)a cross-sectional analysis exploring the association between CADI and MUNW;and(2)aprospective cohort analysis assessing CDAI in relation to cardiometabolic mortality.Adult participants with normalweight from the National Health and Nutrition Examination Survey(2007-2018)were enrolled and classifiedinto quartile groups based on CDAI for the analyses.Results:Among 4,590 participants included in this study,472(7.82%)were diagnosed with MUNW.After full adjustment,the odds ratios(95%confidence intervals)forMUNW across the increasing CDAI levels were 0.80(0.50-1.29),0.85(0.51-1.41),and 0.48(0.26-0.87),respectively(p for trend=0.026).This inverse association appeared to be attenuated among participants aged 20~59years old(p for interaction=0.035).During 32,113 person-years of follow-up,82 cardiometabolic deaths occurred.After full adjustment,the hazard ratios(95%confidence intervals)for cardiometabolic mortality acrossthe increasing CDAI levels were 0.78(0.35-1.73),0.51(0.20-1.27),and 0.40(0.19-0.87),respectively(p for trend=0.014).Conclusions:CDAI was inversely associated with MUNW and cardiometabolic mortality in a normalweightpopulation in the United States.These findings warrant confirmation through interventional studies. 展开更多
关键词 ANTIOXIDANT metabolically unhealthy normal weight NUTRITION the National Health and Nutrition Examination Survey cardiometabolic mortality
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基于改进YOLOv5s的被遮挡交通标志检测算法 被引量:1
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作者 蓝章礼 邢彩卓 张洪 《计算机工程》 北大核心 2025年第5期361-369,共9页
智能驾驶中道路交通标志的检测与识别极其重要,针对交通标志被遮挡时存在目标小、检测精度低的问题,提出一种基于改进YOLOv5s的被遮挡交通标志检测算法。通过自制中国遮挡交通标志数据集(COTSD),解决交通标志在被遮挡情况下数据集缺乏... 智能驾驶中道路交通标志的检测与识别极其重要,针对交通标志被遮挡时存在目标小、检测精度低的问题,提出一种基于改进YOLOv5s的被遮挡交通标志检测算法。通过自制中国遮挡交通标志数据集(COTSD),解决交通标志在被遮挡情况下数据集缺乏的问题,并根据细粒度物体检测需要模型提取丰富判别特征,提出一种基于MobileNetv2改进的主干网络。针对交通标志较小、被遮挡且分辨率较低,普通线性插值方式无法捕捉更高阶、更细节特征的问题,设计一种改进的动态权重上采样模块(DEUM),整合经过通道注意力加权之后的通道信息进行像素重排,生成高分辨率图像;针对综合交并比(CIoU)等损失函数对小目标位置变化敏感的问题,使用归一化高斯Wassertein距离(NWD)来优化边界框回归损失。实验结果表明,该算法在自制被遮挡COTSD上的准确率为93.60%,召回率为72.50%,F1值为81.71%,mAP@0.5为79%;在包含少量被遮挡交通标志的公开CCTSDB上的准确率为92.2%,召回率为78.8%,F1值为85%,mAP@0.5为88.5%。该算法有效提高了被遮挡后交通标志的检测精度。 展开更多
关键词 交通标志检测 遮挡条件 MobileNetv2模型 动态权重上采样模块 归一化高斯Wassertein距离
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城市公共安全韧性评价及提升策略研究——以内蒙古包头市为例
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作者 杨雪 孙秋月 《安全》 2025年第3期19-26,共8页
为强化城市公共安全韧性提升其抗风险水平,立足于经济、社会、基础设施及生态环境4个维度,融合扰动力、适应力与恢复力核心特征,构建城市公共安全韧性评价指标体系;运用熵权法计算指标权重,结合正态云模型对城市公共安全韧性水平进行评... 为强化城市公共安全韧性提升其抗风险水平,立足于经济、社会、基础设施及生态环境4个维度,融合扰动力、适应力与恢复力核心特征,构建城市公共安全韧性评价指标体系;运用熵权法计算指标权重,结合正态云模型对城市公共安全韧性水平进行评价,并应用于内蒙古自治区包头市韧性评价中。结果表明:包头市公共安全综合韧性等级为较高韧性,在经济、基础设施与生态环境方面的韧性水平优于社会韧性。基于评价结果,提出以下提升策略:构建经济韧性架构、健全社会保障机制、夯实基础设施建设、强化生态环境考量。 展开更多
关键词 城市公共安全 韧性评价 熵权法 正态云模型
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福建省沿海区域道路网络扩张对植被动态变化的影响机制 被引量:1
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作者 叶丽敏 黄锦樘 +2 位作者 邹泽耀 陈瑾 胡喜生 《环境科学》 北大核心 2025年第12期7865-7877,共13页
科学分析公路建设对植被动态变化的影响对指导道路网络布设和生态保护具有重要意义.以福建省沿海区域为例,基于2010年和2020年道路数据和归一化植被指数(NDVI),在不同尺度的研究单元上,运用核密度估算、网络分析、双变量空间自相关和地... 科学分析公路建设对植被动态变化的影响对指导道路网络布设和生态保护具有重要意义.以福建省沿海区域为例,基于2010年和2020年道路数据和归一化植被指数(NDVI),在不同尺度的研究单元上,运用核密度估算、网络分析、双变量空间自相关和地理加权回归模型(GWR)等方法,定量分析道路网络格局及其对植被时空变化的影响机制.结果表明,福建省沿海区域的道路核密度(KDE)呈现沿海高内陆低的分层结构,道路网络可达性(ACC)呈现以莆田市、福州市和泉州市为核心向外递减的“核心-边缘”空间分布格局;多尺度双变量空间自相关分析表明,道路网络指标与NDVI呈负相关,KDE与NDVI的Moran's I指数均值为-0.255,ACC与NDVI的Moran's I指数均值为-0.277,ACC与NDVI的相关性较KDE高,空间聚集性更强且受尺度影响较小;ΔKDE-ΔNDVI的Moran's I指数均值为-0.248,ΔACC-ΔNDVI的Moran's I指数均值为0.159,ΔKDE与ΔNDVI呈负相关,而ΔACC与ΔNDVI呈正相关,相关性随着尺度的增大而增大;道路指标与NDVI的相关性在1000 m×1000 m和县域尺度下较高;KDE与NDVI的回归系数在空间上具有较大的变化幅度,空间异质性明显,正回归系数主要集中在宁德市、福州市和漳州市滨海带,负相关性主要分布在研究区中部;ACC与NDVI的回归系数在空间上变化幅度较小,研究区大部分地区的ACC对植被覆盖起到抑制作用,空间聚集性较强且异质性显著.研究结果对促进福建省沿海地区道路网络建设与植被保护的协同具有启示意义. 展开更多
关键词 道路核密度(KDE) 可达性(ACC) 归一化植被指数(NDVI) 空间自相关 地理加权回归(GWR)
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