Trees with Given Diameter Minimizing the Augmented Zagreb Index and Maximizing the ABC Index

Let G be a simple connected graph with vertex set V（G） and edge set E（G）.The augmented Zagreb index of a graph G is defined asAZI（G） =∑uv∈E（G）(d;d;/（d;+ d;-2）);,and the atom-bond connectivity index（ABC index for short） of a graph G is defined asABC（G） =∑uv∈E（G）(（d;+ d;-2）/d;d;),where d;and d;denote the degree of vertices u and v in G,respectively.In this paper,trees with given diameter minimizing the augmented Zagreb index and maximizing the ABC index are determined,respectively.

On Augmented Zagreb Index of Molecular Graphs

The augmented Zagreb index displays a good correlation with the formation heat of octanes and heptanes. The augmented Zagreb index of catacondensed hexagonal systems and molecular trees was discussed. By using the methods of analysis of graph structure and mathematical induction,the catacondensed hexagonal systems with extreme augmented Zagreb index were characterized.The lower bound for augmented Zagreb index of molecular trees with fixed numbers of pendent vertices was given,and the extremal trees were characterized. From these results,we can compare the formation heat of catacondensed hexagonal systems and molecular trees.

Nitroglycerin reduces augmentation index and central blood pressure independent of effects on cardiac preload

Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compared effects of NTG with those of lower body negative pressure (LBNP). Hemodynamic measurements were made at rest,during LBNP (10,20 and 30 mmHg,each for 15 min) and after NTG (10,30 and 100 μg/min,each dose for 15 min) in ten healthy volunteers. Cardiac pre-load,stroke volume and cardiac output were assessed by echocardiography. Central pressure augmentation and central systolic pressure were obtained by radial tonometry using a transfer function. Results LBNP (20 mmHg) and NTG (30 μg/min) reduced pre-load (as measured by the peak velocity of the S wave in the superior vena cava) to a similar degree [by (26.8±3.8)% and (23.9±3.4)%,respectively]. Compared to LBNP,NTG reduced systemic vascular resistance [by (32.9±7.5)%,P<0.01],decreased peripheral and central pressure augmentation [by (20.8±3.4)% units and (12.9±2.9)% units,respectively,each P<0.01]. Conclusion These results suggest that a reduction in pre-load does not explain reduction in pressure augmentation and central systolic blood pressure by NTG and that these effects are mediated through arterial dilation.

Elevated radial arterial augmentation index in hypertensive patients with diastolic dysfunction

Objective To investigate the correlation between augmentation index (AI) of the radial artery and diastolic heart function in patients with hypertension. Methods Echocardiographs were obtained for 305 patients with hypertension. AI, pulse wave velocity (PWV) of peripheral arteries and serum pro-brain natriuretic peptide (proBNP) levels were determined. Correlations and receiver operating characteristic (ROC) curves were drawn between AI values and impaired diastolic function. Results AI levels were significantly increased in patients with impaired diastolic function diagnosed by ultrasound. Assessment of diastolic heart function based on proBNP levels revealed that AI and aortic pulse wave velocity were significantly elevated in patients with impaired diastolic function. The operating curve indicated that AI may be a more accurate and efficient index for the evaluation of impaired diastolic function compared to PWV. Correlation analysis also showed that proBNP levels had altered in parallel with changes in AI and PWV. After adjusting for various factors including age, gender, blood pressure and blood lipid, a positive correlation was observed between proBNP and AI with a correlation coefficient of 0.3697 (P=0.003). However, no correlation between proBNP and aortic PWV was seen after adjustment. Conclusions Changes in radial AI levels may reflect parallel changes in diastolic cardiac function in patients with hypertension, suggesting that AI may be utilized as a non-invasive clinical indicator of diastolic heart function.

Cardiovagal Tone: A Predictor of Heart Rate Adjusted Augmentation Index in Men but Not in Women

Purpose: Aortic augmentation index (AIx) and cardiovagal tone (CVT) are indicators of cardiovascular health. Associations between these variables provide information about their roles in cardiovascular disease. However, evaluating these associations from a gender perspective and gaining an understanding of the relationship between cardiorespiratory fitness and AIx based on gender can provide additional information. Therefore, we examined the relationships between CVT, measured as the log transformed high-frequency power of R-R intervals from electrocardiogram measurements (lnHFR-R);cardiorespiratory fitness, measured as maximum oxygen consumption (VO2max);and AIx at a heart rate of 75 beats·min-1(AIx@75). We hypothesized that the relationships between CVT, cardiorespiratory fitness, and AIx@75 would differ based on gender. Methods: We examined the associations between lnHFR-R, VO2max, and AIx@75 in 41 women and 39 men. Power spectral density analysis of heart rate variability determined lnHFR-R, radial tonometry determined AIx@75 and the Bruce Treadmill Protocol determined VO2max. Results: In men, lnHFR-R positively correlated with and significantly predicted AIx@75 (P = 0.005) but not in women (P = 0.49). For every unit increase in lnHFR-R, there was a 4.6 unit increase in AIx@75 in men versus a 1.0 unit increase in women. There was a significant inverse relationship between VO2max and AIx@75, with VO2max being a significant predictor of AIx@75 in men (P = 0.01). For every unit increase in VO2max, there was a 0.60 unit decrease in AIx@75 in men versus a 0.2 unit decrease in women. Conclusions: The associations between CVT and AIx@75 and between cardiorespiratory fitness and AIx@75 differ by gender. CVT and cardiorespiratory fitness are significant predictors of AIx@75 in men but not in women.

Sex modification of the association of the radial augmentation index and incident hypertension in a Chinese community-based population

BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident hypertension.However,there is still no consensus on whether the augmentation index(AI)affects new onset of hypertension.This study investigated the relationship of radial AI(r AI)and incident hypertension in a Chinese community-based population without hypertension at baseline.METHOD A total of 1,615 Chinese non-hypertensive participants from an atherosclerosis cohort in Beijing,China were included in our analysis.Baseline r AI normalized to heart rate of 75 beats/min(r AIp75)was obtained using HEM-9000 AI.New-onset hypertension was defined as blood pressure≥140/90 mm Hg or self-reported hypertension or taking anti-hypertensive medications at the follow up survey.Multivariate regression models were used to evaluate the impact of r AIp75 on the risk of new-onset hypertension.RESULTS After a mean 2.35-year follow-up,213(13.19%)participants developed incident hypertension.No significant relation between r AIp75 and incident hypertension was observed in the whole population after adjustment for possible confounders(adjusted odds ratio(OR)and 95%confidence interval(CI):1.09[0.95-1.27];P=0.2260).However,r AIp75 was significantly associated with incident hypertension in women,but not in men(adjusted OR and 95%CI:1.29[1.06-1.56],P=0.0113 for women;0.91[0.72-1.15],P=0.4244 for men;P for interaction=0.0133).CONCLUSIONS Sex modified the effect of the r AI on incident hypertension in a Chinese,community-based,non-hypertensive population.Screening of the r AI could be considered in women with a high risk of hypertension for the purpose of primary intervention.

线图、全图和细分图的augmented Zagreb指数

图的augmented Zagreb指数是化学图论中一种新的拓扑指数,在化学中有着许多的应用.研究表明该指数能有效地预测辛烷和庚烷的能量信息.对线图、全图和细分图的augmented Zagreb指数进行了研究.采用分析结构的方法,得到了线图、全图和细分图的augmented Zagreb指数的上界和下界,并且刻画了达到上界和下界时的图类.

建筑物指数与对抗网络结合的检测样本增广

在基于深度学习的遥感图像大范围目标检测中,部分地物获取难度较大,训练结果不佳。因此,利用形态学建筑物指数与生成式对抗网络进行样本增广,减少因检测样本不足导致的模型过拟合问题。通过提取纹理结构信息相关的形态学建筑物指数,将其与原始样本进行叠加,对建筑物的纹理与空间特征进行强化。同时利用已有样本训练生成式对抗网络以增广部分目标类别,并将其与形态学建筑物指数增强后的样本进行合成,以扩充原始样本集。相比于翻转,裁剪,色调变化的增广策略,使用该方法的检测精度在YOLOv5、EfficientDet等模型上的检测精度均有2%~5%的提升。实验证明,利用建筑物指数与生成式对抗网络相结合的样本增广方法对于诸如发电站等特殊感兴趣类别的小样本遥感图像目标检测精度具有明显提升效果。

生成式人工智能驱动的索引编制方法及其在学术规范和评价中的应用

为提高索引编制的效率与质量,应用生成式人工智能的实验方法,针对传统基于规则和概率的索引软件的不足,提出了运用生成式人工智能RAG技术编制索引的方案,即以期刊的卷为单位,利用大语言模型基于论文摘要中的索引词对全文进行主题标引。设计了论文摘要索引数据库系统,能够实现基于大模型海量知识涌现和推理的文本概念抽取和主题标引,从摘要中提取关键信息和新兴知识。探讨了将索引、论文摘要、学术规范与评价关联起来的实际方式,展示了生成式人工智能在索引学和索引编制领域的潜在价值,能够为生成式人工智能技术在图书情报领域的应用推广提供参考。

VAE-ATTGRU模型的股指期货价格预测研究

针对股指期货市场高波动、非平稳、非线性和高信噪比等特性造成的预测难度大的问题,利用变分自编码器(VAE)和循环神经网络(RNN)提出一种基于VAE-ATTGRU的混合深度学习股指期货价格预测模型。利用变分自编码器对股指期货技术指标进行学习,将VAE学习到的潜在因子与原始数据融合实现数据增强,得到更丰富的因子表示;使用循环神经网络对股指期货价格进行预测,发现结合了注意力机制的门控循环单元(ATTGRU)可以对VAE增强后的股指期货数据进行充分学习,对关键特征信息进行捕捉并重新赋予权重。在沪深300股指期货、中证500股指期货和上证50股指期货数据上进行实验,通过均方根误差(RMSE)、平均绝对误差(MAE)、平均绝对百分比误差(MAPE)和决定系数R2对VAE-ATTGRU模型进行评估,发现其在预测精度上优于其他模型。

An Empirical Assessment of the Impact of Nigerian all Share Index, Market Capitalization, and Number of Equities on Gross Domestic Product

A stock exchange is an exchange where stock brokers and traders can buy and sell shares of stock, bonds, and other securities. All listings are included in the Nigerian Stock Exchange All Shares index. In terms of market capitalization, the Nigerian Stock Exchange is the third largest stock exchange in Africa. Objectives: The paper assesses the impact of Nigerian Stock Market (all share index, market capitalization, and number of equities) on Gross domestic product (Economic Growth). Materials and Methods: Regression analysis and ordinary least square technique were employed. Result and Discussion: The series was stationary at 1%, 5%, and 10% α level;the residuals were normally distributed but not serially correlated at 5% α level. All Share Index, Market Capitalization and Total Number of listed Equities have a joint and individual significant effect on Economic Growth (Gross Domestic Product) with Total Number of listed Equities having a negative (opposite) linear relationship with the Gross Domestic Product. The Durbin-Watson statistics (R2 = 0.9910 = 1.3686) suggest that the model is not spurious and it is devoid of positive and negative autocorrelation (DW = 1.3686 > dl = 1.07 and DW = 1.5033 ?-?du = 2.17). Therefore, it can produce meaningful result when used for forecasting a positive relationship between gross domestic product, all share index and market capitalization with a 99.1% R-square value. Significant Positive connection between all share index, market capitalization, the number of equities and gross domestic product suggests that government policies and bills aimed towards rapid development of the capital market should be initiated.

人机协同增强型商务信息管理决策采用的心理机制——自我决定理论视角

随着数据科学和认知智能等新技术的发展,人机协同的增强型商务信息管理决策逐渐成为组织决策的主流方式,它的潜在优势也引起了众多实践者和研究者的高度关注。相较于传统的以管理者为中心的组织决策范式,人机协同决策范式意味着曾经作为工具的机器演变成为了与管理者具有平等地位和同等决策权力的队友。对于管理者而言,机器这一重要角色的转变弱化了管理者自身在决策过程中的重要性,甚至导致管理者对人机协同决策产生潜在抵制行为。为了解决这一关键问题,本研究从自我决定理论出发,系统地优化人机协同增强型商务信息管理决策模式和功能的设计,增加管理者对其“造”(技术就绪度)和“用”(技术接受模型)的感知,以满足管理者的自我决定需要,从而提高管理者对人机协同增强型商务信息管理决策的采纳意愿。

采用机器学习与二维伽马函数的股票指数量化交易策略

为了通过短线交易获取对标股票指数的超额收益,提出一种基于机器学习的股票指数增强型量化交易策略,并实现程序化自动交易。首先生成股票指数的初始特征集,通过最大互信息系数法筛选得21维特征;然后设计双阈值涨跌不平衡标签与3种预测分类方式(T、B-B、B-T),组合构建不同机器学习模型,并对比择优得到多空交易方向的最优机器学习模型分别为LSTM-B-T模型与RF-B-T模型;接着设计基于日内涨跌幅的二维伽马函数;最后使用经二维伽马函数计算得到的类概率判别阈值与最优机器学习模型预测的类概率进行涨跌类别判定,得到交易信号。将该策略应用于中证500指数的股指ETF进行回测与模拟盘交易验证,实验结果表明:相较于随机建仓策略,采用该策略使交易评价指标得到整体性提升;在回测与为期3个月的模拟盘交易验证中使用该策略均能获得对标指数的理想超额收益,分别为11.24%、11.08%。

Increased Risk of Arterial Stiffness in Rhumatoid Arthritis Patients in a Sub-Saharan African Setting

Background: Analysis of arterial stiffness (AS) is a good marker of early arterial disease and an important determinant of cardiovascular risk, independent of other traditional cardiovascular risk factors. Carotid-femoral pulse wave velocity (CfPWV) is the gold standard to evaluate arterial stiffness. There is evidence that patients with rheumatoid arthritis (RA) have a higher arterial stiffness than their age-matched healthy counterparts and thus have higher cardiovascular (CV) risk. However, data on arterial stiffness in African rheumatoid arthritis patients is scarce. Objectives: To determine the patterns of arterial stiffness in rheumatoid arthritis patients in a sub-Saharan African setting, using CfPWV and Augmentation index (AIx). Method: We conducted a case-control study, at the Douala general hospital over four months (February to May 2018) on 63 subjects among which 31 RA patients matched for age and sex with 32 healthy subjects. AIx and CfPWV were determined non-invasively by radial pulse wave analysis and carotid femoral wave analysis respectively, using a sphygmocor Atcor device (SphygmoCor, PWV Medical, Sydney, Australia). Results: The mean age of RA patients was 47 ± 14 years with most of them being females (n = 26, 83.9%). CfPWV was significantly higher in RA patients compared to the control group (mean: 8.85 ± 2.1 vs 7.45 ± 1.38;p ≤ 0.01) as well as was AIx (Median: 33 [26 - 43] vs 26 [20 - 31];p = 0.01). RA (OR: 6.105;95% CI: 1.52 - 24.54;p 1.34;95% CI: 1.14 - 5.17;p = 0.05), elevated CRP levels (OR: 4.01;95% CI: 1.16 - 13.68;p = 0.03) and Hypertension (OR: 5.75;95% CI: 1.24 -11.60;p Conclusion: Arterial stiffness, a well-recognized marker of cardiovascular risk is increased among patients suffering from rheumatoid arthritis when compared to a healthy control group.

预后营养指数对老年女性OVCF病人PVA术后再发椎体骨折的影响

目的调查老年女性骨质疏松性椎体压缩骨折(OVCF)病人行椎体强化术(PVA)后再发椎体骨折的情况及影响因素。方法回顾性调查205例接受PVA术的老年女性OVCF病人,收集其年龄、BMI、入院血常规、血生化指标及骨密度(BMD)等基本情况,调查时间为PVA术后2~40个月,根据是否出现椎体再骨折分为再骨折组及对照组。采用单因素及多因素Cox回归分析老年女性OVCF病人PVA术后再发椎体骨折的影响因素,采用Logistic回归计算独立影响因素的概率,绘制ROC曲线。结果老年女性OVCF病人PVA术后再发椎体骨折发生率为20.5%。Cox回归分析显示,预后营养指数(PNI)、BMD、年龄、是否服用抗骨质疏松(OP)药物是PVA术后再发椎体骨折的独立影响因素;与低PNI病人相比,高PNI病人PVA术后再发骨折风险更低;PNI与是否服用抗OP药物存在交互作用,在高PNI组抗OP药物疗效更好,P interaction<0.05。ROC曲线结果显示,相较于无PNI因素模型,含有PNI因素的模型ROC曲线面积增加了0.066(0.003~0.127)。结论高PNI是老年女性OVCF病人PVA术后再发椎体骨折的保护因素,对PVA术后椎体再骨折有预测价值,可以通过提高抗OP药物的疗效进一步降低再发骨折发生率。

乳晕上切口隆胸手术治疗乳房下垂的临床疗效及患者主观满意度分析

目的探讨乳晕上切口隆胸手术治疗乳房下垂的效果及患者主观满意度。方法选取2019年1月至2021年6月于沈阳名流美容医院就诊的86例乳房下垂患者作为研究对象,根据随机数字表法分为对照组与观察组,每组43例。对照组行常规环状手术,观察组行乳晕上切口隆胸手术。比较两组临床疗效、围手术期指标和患者主观满意度。结果观察组优良率为97.67%,高于对照组的72.09%,差异有统计学意义(P<0.05);观察组手术时间、下床活动时间和住院时间均短于对照组,术中出血量少于对照组,差异有统计学意义(P<0.05);观察组乳头位置、矫正效果、乳房状态、手术创伤、满意程度评分均高于对照组,差异有统计学意义(P<0.05)。结论乳晕上切口隆胸手术治疗乳房下垂的效果较好,利于患者术后恢复,患者满意度高,值得临床推广应用。

关节镜下韧带增强固定与改良Brostrom术对慢性踝关节外侧不稳定患者踝关节功能的影响

目的 对比关节镜下韧带增强固定与改良Brostrom术对慢性踝关节外侧不稳定患者踝关节功能的影响。方法 选择慢性踝关节外侧不稳定患者80例,按随机数表法分为改良Brostrom术组、关节镜下韧带增强固定组,各40例。改良Brostrom术组给予改良Brostrom术治疗,关节镜下韧带增强固定组给予关节镜下韧带增强固定治疗,2组术后均随访1年。比较2组围手术期指标,术前、术后1年踝关节影像学指标,多时间点足与踝功能(FAAM)、美国矫形外科足踝协会(AOFAS)踝与后足功能评分,随访1年切口愈合、复发情况。结果 关节镜下韧带增强固定组术中出血量低于改良Brostrom术组,术后下床时间、手术时间、恢复正常生活时间短于改良Brostrom术组(P <0.05)。术后1年,2组距骨倾斜角、距骨前移距离较术前降低,且关节镜下韧带增强固定组低于改良Brostrom术组(P <0.05)。与术前比较,2组术后6个月、术后1年FAAM(日常运动、体育运动)、AOFAS踝与后足功能评分均呈升高趋势,且术后6个月、术后1年关节镜下韧带增强固定组FAAM(日常运动、体育运动)、AOFAS踝与后足功能评分高于改良Brostrom术组(P <0.05)。随访1年,2组甲级愈合、乙级愈合比例比较,差异无统计学意义(P> 0.05),关节镜下韧带增强固定组复发率低于改良Brostrom术组(P <0.05)。结论 与改良Brostrom术比较,关节镜下韧带增强固定治疗慢性踝关节外侧不稳定可改善患者围手术期指标,促进踝关节功能恢复,优化踝关节影像学指标,降低复发风险。

影响老年人反射波增强指数的诸因素

目的反射波增强指数(AI)是反映动脉反射波的一个指标。在老年人中,AI 是否是反映动脉硬化的一个较好指标,目前存在争议。为了更好地理解在老年人中运用 AI 的意义,我们在～老年人群中研究 AI 的影响因素。方法在上海青浦区赵巷镇选择70岁以上老年人,用 Omron 公司 HEM9000 AI 脉波检测仪进行左侧桡动脉脉搏波分析,心率取校正到75次/min 的 AI 进行统计分析。结果1286例受检者中包括761名(59%)女性,815例(63%)高血压病患者。平均年龄为76.3岁。女性的 AI 显著高于男性(90.3%vs 85.8%,P<0.01)。简单相关分析显示:不论男女,AI(P<0.05)都随着年龄的增加而升高,随身高和血糖水平的增加而降低。男性饮酒者的 AI 显著高于不饮酒者(87.3%vs 85.2%,P=0.03)。多元逐步回归分析显示:身高、平均动脉压和空腹血糖是女性 AI 的独立影响因素。在男性,AI 还受年龄和饮酒的影响。结论在70岁以上老年人中,年龄、性别、身高、平均动脉压和血糖水平是 AI 的独立影响因素。

汉族人群中血压与动脉硬化关系的研究

目的 :探讨汉族人群中家庭测量血压与动脉硬化的关系。方法 :将 471名受试者分为青年组 (n =2 3 5 )和中年组 (n =2 3 6) ,各组又分为血压正常者和高血压者。对受试者进行 2次家访 ,每次家访各测 5次血压 ,取其 10次读数的平均值作为血压值。应用动脉脉搏波分析 (PWA )仪记录受试者桡动脉脉搏波形 ,经计算机自动转化为中心动脉脉搏波 ,以反射波增强指数 (AIx)作为反映全身动脉硬化的参数。结果 :血压正常者PWA结果显示 ,中年组与青年组比较增强指数有极显著性差异 (P <0 .0 1) ,经年龄调整后两组间无显著性差异。两组中高血压者与血压正常者比较增强指数均升高 ,有极显著性差异 (P均 <0 .0 1)。即使在血压正常者中 ,血压正常高值者 (血压 13 0～ 13 9/ 85～ 89mmHg ,1mmHg =0 .13 3kPa)增强指数也显著高于血压正常值者 (血压 <13 0 / 85mmHg ,P <0 0 0 1)。将增强指数作为因变量 ,年龄、身高、心率、家访时的收缩压及舒张压作为自变量进行多元回归分析显示 ,受试者年龄及收缩压与增强指数呈显著的正相关。结论 :血压正常者中 ,增强指数随年龄的增加而升高。高血压者与血压正常者相比 ,增强指数显著升高 ,提示高血压患者动脉顺应性下降、动脉硬化 ;收缩压与动脉顺应性显著相关。即使血压正常高值者 ,增?

血管回声跟踪技术对颈动脉脉搏波放大指数的检测及其意义

目的探讨血管回声跟踪技术（ET）对颈动脉脉搏波放大指数（AI）的检测及其临床意义。方法应用ET技术检测不同年龄正常人145例、高血压患者48例、糖尿病患者26例、终末期肾病20例的AI,正常健康人分为5个年龄组：20～29岁23人，30-39岁22人，40～49岁35人，50～59岁34人，≥60岁31人。比较不同性别及不同年龄组间的AI值有无差异；比较本组各年龄组ET检测的AI与其他方法测得同龄人的AI；比较上述各疾病与同龄正常人AI的差异。用SAS6．12做统计分析。结果AI无性别差异但有年龄差异：在上述5个年龄组的AI测值分别为5．2、7．6、12．8、16．2和20．8，各年龄组ET检测的AI与其他作者其他方法测定的AI相关性良好；高血压、糖尿病及终末期肾病患者的AI均较其同龄人增高。结论ET技术中的脉搏波放大指数AI能较好地反映颈动脉弹性情况，随着年龄增高，高血压、糖尿病及终末期肾病患者的AI明显增高。