Modified slow-fast analysis method for slow-fast dynamical systems with two scales in frequency domain

A modified slow-fast analysis method is presented for the periodically excited non-autonomous dynamical system with an order gap between the exciting frequency and the natural frequency.By regarding the exciting term as a slow-varying parameter,a generalized autonomous fast subsystem can be defined,the equilibrium branches as well as the bifurcations of which can be employed to account for the mechanism of the bursting oscillations by combining the transformed phase portrait introduced.As an example,a typical periodically excited Hartley model is used to demonstrate the validness of the method,in which the exciting frequency is far less than the natural frequency.The equilibrium branches and their bifurcations of the fast subsystem with the variation of the slow-varying parameter are presented.Bursting oscillations for two typical cases are considered,which reveals that,fold bifurcation may cause the the trajectory to jump between different equilibrium branches,while Hopf bifurcation may cause the trajectory to oscillate around the stable limit cycle.

Effect of psychological nursing interventions on effectiveness and quality of life in schizophrenia patients receiving modified electroconvulsive therapy

BACKGROUND Schizophrenia is a common and severe mental disorder characterized by severe thought disturbances,hallucinations,delusions,and emotional instability.For some patients,conventional treatment methods may not effectively alleviate symptoms,necessitating the use of alternative therapeutic approaches.Modified electroconvulsive therapy(MECT)is an effective treatment modality for schizophrenia,inducing anti-depressive and antipsychotic effects through the stimulation of brain electrical activity.AIM To explore the impact of psychological nursing intervention(PNI)before and after MECT on the efficacy and quality of life of patients with schizophrenia.METHODS Eighty patients with schizophrenia who received MECT treatment from 2021 to 2023 were randomly divided into two groups:The intervention group(n=40)and the control group(n=40).The intervention group received PNI before and after MECT,while the control group received routine nursing care.The efficacy of MECT was evaluated by the Positive and Negative Syndrome Scale(PANSS)and the Clinical Global Impression Scale(CGI)before and after the treatment.The quality of life was assessed by the Short Form 36 Health Survey(SF-36)after the treatment.RESUITS The intervention group had significantly lower scores of PANSS and CGI than the control group after the treatment(P<0.05).The intervention group also had significantly higher scores of SF-36 than the control group in all domains except physical functioning(P<0.05).CONCLUSION PNI before and after MECT can improve the efficacy and quality of life of patients with schizophrenia.It is suggested that nurses should provide individualized and comprehensive psychological care for patients undergoing MECT to enhance their recovery and well-being.

APPLICATION OF THE MODIFIED METHOD OF MULTIPLE SCALES TO THE BENDING PROBLEMS FOR CIRCULAR THIN PLATE AT VERY LARGE DEFLECTION AND THE ASYMPTOTICS OF SOLUTIONS(Ⅱ)

This paper is a continuation of part (Ⅰ), on the asymptotics behaviors of the series solutions investigated in (Ⅰ). The remainder terms of the series solutions are estimated by the maximum norm.

APPLICATION OF THE MODIFIED METHOD OF MULTIPLE SCALES TO THE BENDING PROBLEMS FOR CIRCULAR THIN PLATE AT VERY LARGE DEFLECTION ANDTHE ASYMPTOTICS OF SOLUTIONS (Ⅰ)

In this paper, the modified method of multiple scales is applied to study the bending problems for circular thin plate with large deflection under the hinged and simply supported edge conditions. Theseries solutions are constructed, the boundary layer effects are analysed and their asymptotics are proved.

The Rank of Rank-2 Modified Matrix

In this paper, the authors discuss the relationship in detail between the rank of M in the modified matrix M = A ＋ BC^＊ and the rank of matrix A. The authors do believe the results are useful tools in the modified matrices.

NEW LIMITED MEMORY SYMMETRIC RANK ONE ALGORITHM FOR LARGE-SCALE UNCONSTRAINED OPTIMIZATION

A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one （SSR1） update with the limited memory and nonmonotone line search technique. In this algorithm, the descent search direction is generated by inverse limited memory SSR1 update, thus simplifying the computation. Numerical comparison of the algorithm and the famous limited memory BFGS algorithm is given. Comparison results indicate that the new algorithm can process a kind of large-scale unconstrained optimization problems.

Assessing field vulnerability to phosphorus loss in Beijing agricultural area using Revised Field Phosphorus Ranking Scheme

Guanting Reservoir, one of the drinking water supply sources of Beijing, suffers from water eutrophication. It is mainly supplied by Guishui River. Thus, to investigate the reasons of phosphorus （P） loss and improve the P management strategies in Guishui River watershed are important for the safety of drinking water in this region. In this study, a Revised Field P Ranking Scheme （PRS） was developed to reflect the field vulnerability of P loss at the field scale based on the Field PRS. In this new scheme, six factors are included, and each one was assigned a relative weight and a determination method. The affecting factors were classified into transport factors and source factors, and, the standards of environmental quality on surface water and soil erosion classification and degradation of the China were used in this scheme. By the new scheme, thirty-four fields in the Guishui River were categorized as ＂low＂, ＂medium＂ or ＂high＂ potential for P loss into the runoff. The results showed that the P loss risks of orchard and vegetable fields were higher than that of corn and soybean fields. The source factors were the main factors to affect P loss from the study area. In the study area, controlling P input and improving P usage efficiency are critical to decrease P loss. Based on the results, it was suggested that more attention should be paid on the fields of vegetable and orchard since they have extremely high usage rate of P and high soil test of P. Compared with P surplus by field measurements, the Revised Field PRS was more suitable for reflecting the characteristics of fields, and had higher potential capacity to identify critical source areas of P loss than PRS.

Modified Xiaochaihu Decoction for gastroesophageal reflux disease:A randomized double-simulation controlled trial

BACKGROUND Gastroesophageal reflux disease(GERD)has a high prevalence worldwide,and its incidence is increasing annually.Modified Xiaochaihu Decoction(MXD)could relieve the symptoms of GERD,but the effects of MXD on GERD manifestations and relapse prevention need to be further explained.Therefore,we performed a prospective,double-blind,and double-simulation study.AIM To verify the efficacy of MXD for GERD and its effect on esophageal motility.METHODS Using randomization,double-blinding,and a simulation design,288 participants with GERD were randomized to the treatment group and control group and received herbs(MXD)plus omeprazole simulation and omeprazole plus herbs simulation,respectively,for 4 wk.The GERD-Q scale score and esophageal manometry were measured at baseline,after treatment,and at 1 mo and 3 mo follow-up visits when medication was complete to evaluate recurrence indicators.RESULTS The GERD-Q scale score in both groups decreased significantly compared to those before treatment(P<0.01).However,no significant difference was observed between the two groups(P>0.05).Esophageal manometry showed that participants with lower esophageal sphincter pressure reduction and the proportion of ineffective swallowing(more than 50%)improved in both groups from baseline(P<0.01),especially in the treatment group(P<0.05).The percentage of small intermittent contractions,large intermittent contractions,and increased pre-phase contractions in the treatment group significantly improved compared with baseline(P<0.05)but did not improve in the control group(P>0.05).There was no significant difference between the groups after treatment(P>0.05).The percentage of weak esophageal contractility(distal contractile integral<450 mmHg·s·cm),improved in both groups(P<0.01),but no significant difference was observed between the groups after treatment(P>0.05).The relapse rate in the treatment group was lower than that in the control group at the 1 mo(P<0.01)and 3 mo follow-up(P<0.05).CONCLUSION MXD has a similar therapeutic effect to omeprazole in mild-to-moderate GERD.The therapeutic effect may be related to increased pressure in the lower esophageal sphincter and reduced ineffective swallowing.

Modified SIFT descriptor and key-point matching for fast and robust image mosaic

To improve the performance of the scale invariant feature transform （ SIFT）, a modified SIFT （M-SIFT） descriptor is proposed to realize fast and robust key-point extraction and matching. In descriptor generation, 3 rotation-invariant concentric-ring grids around the key-point location are used instead of 16 square grids used in the original SIFT. Then, 10 orientations are accumulated for each grid, which results in a 30-dimension descriptor. In descriptor matching, rough rejection mismatches is proposed based on the difference of grey information between matching points. The per- formance of the proposed method is tested for image mosaic on simulated and real-worid images. Experimental results show that the M-SIFT descriptor inherits the SIFT＇ s ability of being invariant to image scale and rotation, illumination change and affine distortion. Besides the time cost of feature extraction is reduced by 50% compared with the original SIFT. And the rough rejection mismatches can reject at least 70% of mismatches. The results also demonstrate that the performance of the pro- posed M-SIFT method is superior to other improved SIFT methods in speed and robustness.

Size dependent free vibration analysis of functionally graded piezoelectric micro/nano shell based on modified couple stress theory with considering thickness stretching effect

Higher-order shear and normal deformation theory is used in this paper to account thickness stretching effect for free vibration analysis of the cylindrical micro/nano shell subjected to an applied voltage and uniform temperature rising.Size dependency is included in governing equations based on the modified couple stress theory.Hamilton’s principle is used to derive governing equations of the cylindrical micro/nano shell.Solution procedure is developed using Navier technique for simply-supported boundary conditions.The numerical results are presented to investigate the effect of significant parameters such as some dimensionless geometric parameters,material properties,applied voltages and temperature rising on the free vibration responses.

Classifying and ranking DMUs in interval DEA

During efficiency evaluating by DEA, the inputs and outputs of DMUs may be intervals because of insufficient information or measure error. For this reason, interval DEA is proposed. To make the efficiency scores more discriminative, this paper builds an Interval Modified DEA (IMDEA) model based on MDEA. Furthermore, models of obtaining upper and lower bounds of the efficiency scores for each DMU are set up. Based on this, the DMUs are classified into three types. Next, a new order relation between intervals which can express the DM’s preference to the three types is proposed. As a result, a full and more convictive ranking is made on all the DMUs. Finally an example is given.

Modified projective synchronization with complex scaling factors of uncertain real chaos and complex chaos

To increase the variety and security of communication, we present the definitions of modified projective synchronization with complex scaling factors （CMPS） of real chaotic systems and complex chaotic systems, where complex scaling factors establish a link between real chaos and complex chaos. Considering all situations of unknown parameters and pseudo-gradient condition, we design adaptive CMPS schemes based on the speed-gradient method for the real drive chaotic system and complex response chaotic system and for the complex drive chaotic system and the real response chaotic system, respectively. The convergence factors and dynamical control strength are added to regulate the convergence speed and increase robustness. Numerical simulations verify the feasibility and effectiveness of the presented schemes.

基于PageRank改进算法的电网脆弱线路快速辨识(一):理论基础

作为两篇系列文章的第一篇,该文结合网络拓扑和电网运行状态,提出了一种适用于快速辨识电网脆弱线路的Page Rank改进算法并阐明其原理。首先,介绍Page Rank基本算法,并讨论了将其直接应用于辨识电网脆弱线路的局限性。其次,为了克服以上局限性,提出相关性网络和衍生网络的概念,然后在此基础上建立分析线路脆弱度Page Rank改进模型。最后,基于此模型给出线路脆弱度计算的解析表达式,并提出快速辨识脆弱线路的方法。

卒中登记研究中Barthel指数和改良的Rankin量表的适用性与相关性研究

目的 评价Barthel指数 (BI)和改良的Rankin量表 (MRS)在脑卒中登记研究中作为预后指标的适用性 ,并分析二者由计量资料转换为二分类变量资料时分界值的对应关系。方法 前瞻性连续登记 912例住院的脑卒中患者 ,在发生卒中后 1、3、6和 12个月时盲法随访所有病例的BI和MRS评分。对卒中后不同时间的BI和MRS评分分布、天花板效应和地板效应进行评价 ,并通过建立BI和MRS评分的logistic回归模型 ,计算分别以MRS评分≤ 1和≤ 2作为划分残疾与否的分界值时BI评分对应的分界值。结果 BI和MRS评分共评价 2 82 9人次 ,发生卒中后 3、6和 12个月时BI最高评分例数分别为总例数的 5 4 8%、6 2 2 %和 6 8 3% ,显著高于相应的MRS最高评分例数。BI和MRS评分存在显著相关性 (Spearman s相关系数0 887,P <0 0 5 ) ;以MRS评分≤ 1和≤ 2分别作为划分残疾与否的分界值时 ,BI评分对应的分界值为≥ 90和≥ 85。结论 本研究结果显示 ,在脑卒中登记研究中 ,BI作为长期功能残疾的评价指标时具有显著的天花板效应 ,BI和MRS评分具有显著相关性。结合国外相关报道 ,我们建议在今后的研究中 ,可试依据MRS评分≤ 2或BI评分≥ 85作为划分脑卒中患者是否残疾的分界值。

国内脑卒中临床试验疗效判断方法中改良Rankin评分的应用现状

目的分析国内脑卒中临床试验疗效判断方法中改良Rankin评分应用的现状和存在的问题。方法人工检索中国知网、万方、维普三大中文数据库中2013年9月之前发表的文献。纳入所有研究脑卒中治疗措施、自述为随机或半随机临床对照试验、疗效评价指标中使用改良Rankin评分(modified Rankin scale,m RS)的人体研究报告。排除关于蛛网膜下腔出血和TIA的试验。对脑卒中类型、m RS分值的统计分析方法、随访时间、是否采用盲法判断疗效、干预类型及阳性结果率等方面进行分析。结果共有298个试验使用m RS,其中缺血性卒中212个(71.14%),出血性卒中64个(21.48%),包含缺血性卒中和出血性卒中的22个(7.38%)。急性脑卒中(发病时间<14d)272个(91.28%)。在对m RS分值的统计分析中按连续性资料进行分析并采用t检验或方差分析的有149个(50.00%),按等级资料采用秩和检验或多分类卡方检验进行分析的有66个(22.15%),将资料转换为二分类资料进行统计分析的有76个(25.50%)。将m RS与其他评分量表一起作为卒中疗效判定指标的有37个(12.42%)。随访时间10d至2年,中位时间90(30,90)d。仅15个试验(5.03%)描述使用盲法对疗效进行评价。药物治疗179个(60.07%),康复治疗23个(7.72%),外科治疗31个(10.40%%),综合治疗43个(14.43%),管理方式7个(2.35%),护理2个(0.67%),其他治疗方式13个(4.36%)。259个(86.91%)试验显示出有统计学意义的阳性结果。结论国内脑卒中临床试验疗效判断方法中m RS的应用与国外相比,在随访时间、盲法判断疗效、mRS的统计分析方法上存在较大差异。

急性脑卒中患者早期神经功能恶化的评估及改良Rankin评分的随访

目的:探讨低分子肝素和阿司匹林治疗急性缺血性脑卒中患者早期神经功能恶化及使用改良Rankin评分量表(m RS)随访发病90 d患者预后情况。方法:收治急性缺血性脑卒中患者1 368例,随机分为两组。分别采用低分子肝素联合阿司匹林和阿司匹林治疗,比较两组治疗效果。结果:发病10 d,7.89%(108/1368)患者出现早期神经功能恶化,其中低分子肝素组出现3.95%(27/683),阿司匹林组出现11.82%(81/685)。结论:早期神经功能恶化可被视为不良预后的一个指标;m RS得分≤2分的患者预后优于≥3分的患者;对m RS差的患者需要开展更早的和积极的医疗及护理干预。

护骨素-RANK-RANKL轴在瓣膜病合并房颤患者行改良迷宫术后窦律维持中的作用

目的:探讨护骨素-核因子кB受体活化因子(receptor activator of nuclear factor-κB,RANK)-RANK配体(RANK ligand,RANKL)与瓣膜病合并持续性房颤患者行改良迷宫术后转复的窦性心律能否稳定维持的关系。方法:选取瓣膜病合并持续性房颤行改良迷宫术患者共65例,以术后3个月内房颤是否复发分为房颤复发组39例和窦性心律组26例。术中取左心耳组织,采用蛋白质印迹及免疫组织化学法检测护骨素、RANK、RANKL的表达,用Masson染色比较两组患者左心耳组织的间质纤维化程度。结果:房颤复发组左心耳组织中RANK和RANKL的表达水平以及RANKL/护骨素比值均明显高于窦性心律组,房颤复发组的胶原容积分数(CVF)也显著高于窦性心律组,差异有统计学意义;且房颤复发组RANKL的表达量、RANKL/护骨素比值与CVF呈正相关。结论:护骨素-RANK-RANKL轴可能通过影响心房的结构重构参与瓣膜病合并房颤患者行改良迷宫术后房颤的复发。

PNF联合下肢机器人训练对脑卒中患者姿势及步行功能的影响

目的:探讨PNF联合下肢机器人训练对脑卒中患者姿势及步行功能的影响。方法:采用随机数字表法将44例脑卒中患者分成观察组和对照组各22例,两组患者均给予常规康复治疗及PNF训练,观察组在此基础上增加下肢机器人训练,分别于治疗前及治疗4周后采用脑卒中姿势量表(PASS)、功能性步行分级量表(FAC)、Berg平衡量表、肌张力改良Ashworth量表(MAS)评估患者的姿势及平衡步行功能。结果:治疗前,两组患者各量表评分差异均无统计学意义(P>0.05)。治疗4周后,两组患者PASS、FAC功能性步行分级、Berg量表评分较治疗前差异均有统计学意义(P<0.001),且观察组较对照组差异有统计学意义(P<0.001),两组患者MAS分级差异无统计学意义(P>0.05)。结论:PNF联合下肢机器人训练,有助于改善脑卒中患者姿势及平衡功能,提高其步行能力。

大数据下基于异步累积更新的高效P-Rank计算方法

P-Rank是SimRank的扩展形式,也是一种相似度度量方法,被用来计算网络中任意两个结点的相似性.不同于SimRank只考虑结点的入度信息,P-Rank还加入了结点的出度信息,从而更加客观准确地评价结点间的相似程度.随着大数据时代的到来,P-Rank需要处理的数据日益增大.使用MapReduce等分布式模型实现大规模P-Rank迭代计算的方法,本质上是一种同步迭代方法,不可避免地具有同步迭代方法的缺点:迭代时间(尤其是迭代过程中处理器等待的时间)长,计算速度慢,因此效率低下.为了解决这一问题,采用了一种迭代计算方法——异步累积更新算法.这个算法实现了异步计算,减少了计算过程处理器结点的等待时间,提高了计算速度,节省了时间开销.从异步的角度实现了P-Rank算法,将异步累积更新算法应用在了P-Rank上,并进行了对比实验.实验结果表明该算法有效地提高了计算收敛速度.

Predictors of Falls Efficacy Scale responses among nursing home residents in China

Objectives:The objective of this study was to examine the falls efficacy of older adults in nursing homes and the related predictors of falling.Methods:A sample of 317 older adults was recruited from 18 nursing homes in the Fujian province of China.The Modified Falls Efficacy Scale(MFES)and Kessler Psychological Distress Scale(K10)were employed to collect data.Results:The falls efficacy of older adults was moderate(7.80±1.17).The falls efficacy questionnaire item“Get dressed and undressed”scored the highest(9.12±1.440),while“Crossing roads”scored the lowest(5.77±3.371).Multiple regression analysis demonstrated that mental health status,degree of self-care,age and gender were each predictors of the falls efficacy of older adults.Conclusions:Falls efficacy enhancing programs for nursing home residents should take mental health status,degree of self-care,age and gender into account.