graph theory

图论
  • 文章类型: Journal Article
    阿尔茨海默病(AD)是一种具有挑战性的神经退行性疾病,需要早期诊断和干预。这项研究利用了机器学习(ML)和图论指标,从静息态功能磁共振成像(rs-fMRI)数据中得出预测AD的数据。使用西南大学成人寿命数据集(SALD,年龄21-76岁)和开放获取系列成像研究(OASIS,年龄64-95岁)数据集,包含112名参与者,开发了各种ML模型用于AD预测。该研究确定了全面了解AD中脑网络拓扑和功能连通性的关键特征。通过5倍交叉验证,所有模型都表现出相当大的预测能力(准确率在82-92%范围内),支持向量机模型作为最佳模型,准确率为92%。目前的研究表明,前13个地区,基于最重要的区分特征识别,与丘脑失去了重要的联系.黑质的功能连接强度持续下降,网状结构,黑质,parscompacta,与健康成年人和衰老个体相比,AD受试者中的伏隔核。目前的发现证实了早期的研究,采用各种神经成像技术。这项研究标志着整合ML的综合方法的转化潜力,图论和rs-fMRI分析在AD预测中的应用,为AD的更准确诊断和早期预测提供潜在的生物标志物。
    Alzheimer\'s disease (AD) is a challenging neurodegenerative condition, necessitating early diagnosis and intervention. This research leverages machine learning (ML) and graph theory metrics, derived from resting-state functional magnetic resonance imaging (rs-fMRI) data to predict AD. Using Southwest University Adult Lifespan Dataset (SALD, age 21-76 years) and the Open Access Series of Imaging Studies (OASIS, age 64-95 years) dataset, containing 112 participants, various ML models were developed for the purpose of AD prediction. The study identifies key features for a comprehensive understanding of brain network topology and functional connectivity in AD. Through a 5-fold cross-validation, all models demonstrate substantial predictive capabilities (accuracy in 82-92% range), with the support vector machine model standing out as the best having an accuracy of 92%. Present study suggests that top 13 regions, identified based on most important discriminating features, have lost significant connections with thalamus. The functional connection strengths were consistently declined for substantia nigra, pars reticulata, substantia nigra, pars compacta, and nucleus accumbens among AD subjects as compared to healthy adults and aging individuals. The present finding corroborate with the earlier studies, employing various neuroimagining techniques. This research signifies the translational potential of a comprehensive approach integrating ML, graph theory and rs-fMRI analysis in AD prediction, offering potential biomarker for more accurate diagnostics and early prediction of AD.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    相变通常使用阶数参数进行量化,如晶格距离和径向分布函数,它可以识别晶体材料或具有较大结构差异的高对比度相的细微变化。然而,识别具有高复杂性的阶段,在相变之前的结构波动期间,多尺度组织和复杂模式,这对于理解阶段之间的系统路径至关重要,对于那些传统的分析来说是具有挑战性的。这里,结果表明,对于两个模型系统-热致液晶和溶致水/表面活性剂混合物-图论(GT)描述符可以成功地识别复杂的相,结合了分子和纳米级的组织水平,这些水平很难用传统方法表征。此外,GT描述符还揭示了不同阶段之间的路径。具体来说,中心性参数和基于节点的分形维数量化了过渡之前的系统行为,捕获波动诱导的聚集体破碎及其长期合作相互作用。GT参数化可以推广到广泛的化学系统,并有助于复杂纳米结构的生长机制。
    Phase transitions are typically quantified using order parameters, such as crystal lattice distances and radial distribution functions, which can identify subtle changes in crystalline materials or high-contrast phases with large structural differences. However, the identification of phases with high complexity, multiscale organization and of complex patterns during the structural fluctuations preceding phase transitions, which are essential for understanding the system pathways between phases, is challenging for those traditional analyses. Here, it is shown that for two model systems- thermotropic liquid crystals and a lyotropic water/surfactant mixtures-graph theoretical (GT) descriptors can successfully identify complex phases combining molecular and nanoscale levels of organization that are hard to characterize with traditional methodologies. Furthermore, the GT descriptors also reveal the pathways between the different phases. Specifically, centrality parameters and node-based fractal dimension quantify the system behavior preceding the transitions, capturing fluctuation-induced breakup of aggregates and their long-range cooperative interactions. GT parameterization can be generalized for a wide range of chemical systems and be instrumental for the growth mechanisms of complex nanostructures.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在这项研究中,我们提出了一种使用离散数学中的图论来指导压力性尿失禁(SUI)和急迫性尿失禁(UUI)治疗选择的方法。我们之前的研究积累了150例接受无张力阴道吊带(TVT)的患者的数据,透声带(TOT),和2014年至2016年间的阴道非消融术YAG激光(VEL)手术。网络图是使用此数据创建的。治疗TVT,TOT,还有VEL,以及患者特征(1小时垫测试:1-hrPadTest,膀胱过度活动症症状评分:OABSS),在网络图中表示为节点和边。然后,我们采用启发式函数为SUI和UUI患者选择最佳治疗方法。此过程使医疗专业人员能够通过计算连接1-hrPadTest和OABSS的最短路径,轻松地为患有SUI和UUI问题的患者导航数据。这些结果,这与以前的研究是一致的,表明VEL是最佳治疗方法。与以前的研究不同,这些研究采用了患者难以理解的统计知识,我们的研究帮助患者在视觉上理解和制定定制的治疗计划。这种方法为治疗尿失禁的临床决策提供了新的视角。据我们所知,这是第一项将离散数学应用于尿失禁治疗的患者决策的研究。
    In this study, we propose a method for navigating the choice of treatment for stress urinary incontinence (SUI) and urgency urinary incontinence (UUI) using graph theory in discrete mathematics. Our previous study accumulated data from 150 patients who underwent tension-free vaginal tape (TVT), transobturator tape (TOT), and vaginal non-ablation Erbium YAG laser (VEL) surgeries between 2014 and 2016. Network diagrams were created using this data. The treatments TVT, TOT, and VEL, along with patient characteristics (1-hour pad test: 1-hrPadTest, Overactive Bladder Symptom Score: OABSS), were represented as nodes and edges in the network diagram. We then employed a heuristic function to select the optimal treatment method for the patients with SUI and UUI. This process enables medical professionals to easily navigate the data for patients with both SUI and UUI concerns by calculating the shortest path connecting the 1-hrPadTest and OABSS. These results, which are consistent with those of previous studies, suggest that VEL is the optimal treatment. Unlike previous studies that employed statistical knowledge that is challenging for patients to understand, our study aids patients in visually comprehending and developing a customized treatment plan. This approach introduces a novel perspective for clinical decision-making in the treatment of urinary incontinence. To the best of our knowledge, this is the first study to apply discrete mathematics to patient decision-making for urinary incontinence treatment.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Case Reports
    此病例报告描述了希望怀孕的36岁压力性尿失禁(SUI)和膀胱过度活动症(OAB)妇女的治疗选择过程。患者有高血压和2型糖尿病的合并症,这需要考虑改善她的生活质量和生殖健康。最近开发的使用离散数学方法的决策支持工具用于选择适合患者个人情况的治疗方法。分析确定阴道铒激光(VEL)治疗(RenovalaseSPDynamisFotonad.o.o,卢布尔雅那,斯洛文尼亚)最适合该患者。VEL治疗可显着改善SUI和OAB,改变降压药可消除夜尿症。该案例表明图论在SUI患者治疗选择中的潜在应用。
    This case report describes the treatment selection process for a 36-year-old woman with stress urinary incontinence (SUI) and an overactive bladder (OAB) who desired pregnancy. The patient had comorbidities of hypertension and type 2 diabetes, which required consideration to improve her quality of life and reproductive health. A recently developed decision support tool using a discrete mathematical approach was used to select a treatment method tailored to the patient\'s individual situation. The analysis determined that vaginal erbium laser (VEL) treatment (Renovalase SP Dynamis Fotona d.o.o, Ljubljana, Slovenia) was the most suitable for this patient. VEL treatment significantly improved both SUI and OAB and changing antihypertensive medication eliminated nocturia. This case suggests the potential application of graph theory in treatment selection for SUI patients.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    多发性硬化症(MS)是一种中枢神经系统的神经炎症和神经退行性疾病,通常以残疾和认知障碍为特征。MS的病理标志在于脱髓鞘,因此受损的结构和功能神经元途径。最近的研究表明,MS显示出主要网络枢纽区域如丘脑的广泛结构断开,结合功能网络重组,这可能主要与较差的临床功能有关。MS可以,因此,被认为是一种网络紊乱,这篇综述概述了MS在网络神经科学领域的最新创新。
    Multiple sclerosis (MS) is a neuroinflammatory and neurodegenerative disease of the central nervous system, commonly featuring disability and cognitive impairment. The pathologic hallmark of MS lies in demyelination and hence impaired structural and functional neuronal pathways. Recent studies have shown that MS shows extensive structural disconnection of key network hub areas like the thalamus, combined with a functional network reorganization that can mostly be related to poorer clinical functioning. As MS can, therefore, be considered a network disorder, this review outlines recent innovations in the field of network neuroscience in MS.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    目的:确定主观认知下降(SCD)的个体在结构网络中是否具有全脑网络特征和脑内节点特征的变化,以及有无载脂蛋白E4(APOEε4)的SCD之间是否存在差异。
    方法:这项横断面研究包括36名无APOEε4的无SCD个体(健康对照,HC组),21名患有APOEε4的SCD患者(APOEε4+组),33例SCD无APOEε4(APOEε4组)。使用基于分数各向异性(FA)的确定性纤维跟踪方法构建白质结构网络。采用图论分析三组的全脑网络特征和脑内节点特征。
    结果:关于全脑网络特征,这三个群体在他们的结构网络中都表现出了小世界性。APOEε4+和APOEε4-组的聚类系数(Cp)和局部效率(Eloc)均显著低于HC组(p<0.05),但APOEε4+和APOEε4-组之间的Cp或Eloc没有显着差异。关于脑内结节特征,在一些大脑区域有显著差异,主要是默认模式网络(DMN),枕叶,颞叶,和皮质下区域。APOEeε4+组和APOEeε4-组的脑内结节特征变化不同。
    结论:患有SCD的个体表现出全脑网络特征和结构网络中脑内节点特征的变化。此外,APOEε4+和APOEε4-个体之间存在差异。
    OBJECTIVE: To determine whether individuals with subjective cognitive decline (SCD) have changes in whole-brain network characteristics and intracerebral node characteristics in the structural network, and whether there is a difference between SCD with and without Apolipoprotein E4 (APOEε4).
    METHODS: This cross-sectional study included 36 individuals without SCD without APOEε4 (healthy control, HC group), 21 individuals with SCD with APOEε4 (APOEε4+ group), and 33 individuals with SCD without APOEε4 (APOEε4- group). The white matter structural network was constructed using the fractional anisotropy (FA) based deterministic fiber tracking method. Graph theory was used to analyze the whole-brain network characteristics and intracerebral node characteristics of the three groups.
    RESULTS: Regarding the whole-brain network characteristics, all three groups exhibited small-worldness in their structural networks. The clustering coefficient (Cp) and local efficiency (Eloc) in the APOEε4+ and APOEε4- groups were significantly lower than in the HC group (p < 0.05), but no significant difference in Cp or Eloc was observed between the APOEε4+ and APOEε4- groups. Regarding intracerebral node characteristics, there were significant differences in some brain regions, mainly the default mode network (DMN), the occipital lobe, the temporal lobe, and subcortical regions. The change in intracerebral node characteristics was different between the APOEε4+ group and the APOEε4- group.
    CONCLUSIONS: Individuals with SCD demonstrate changes in whole-brain network characteristics and intracerebral node characteristics in the structural network. Moreover, differences exist between APOEε4+ and APOEε4- individuals.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:本文介绍了一种新颖的指标,旨在揭示与阿尔茨海默病(AD)相关的特定大脑连接模式,根据神经心理学模式定义。
    方法:370人的脑电图(EEG)记录,包括170名健康受试者和200名轻度AD患者,通过协调采集设置,在不同的临床中心使用不同的采集设备进行采集。这项研究采用了一种新的衍生小世界(SW)指数,SWcomb,作为一个综合指标,旨在整合七个SW参数,在典型的脑电图频带上计算。目的是创建一个统一的索引,以有效区分具有与AD相容的神经心理学模式的个体与健康者。
    结果:结果显示,健康组的SWcomb值最低,而AD组显示最高的SWcomb。
    结论:这些发现表明,SWcomb指数代表了一种易于执行的,低成本,广泛可用的非侵入性生物标志物,用于区分健康个体和AD患者。
    This article introduces a novel index aimed at uncovering specific brain connectivity patterns associated with Alzheimer\'s disease (AD), defined according to neuropsychological patterns.
    Electroencephalographic (EEG) recordings of 370 people, including 170 healthy subjects and 200 mild-AD patients, were acquired in different clinical centres using different acquisition equipment by harmonising acquisition settings. The study employed a new derived Small World (SW) index, SWcomb, that serves as a comprehensive metric designed to integrate the seven SW parameters, computed across the typical EEG frequency bands. The objective is to create a unified index that effectively distinguishes individuals with a neuropsychological pattern compatible with AD from healthy ones.
    Results showed that the healthy group exhibited the lowest SWcomb values, while the AD group displayed the highest SWcomb ones.
    These findings suggest that SWcomb index represents an easy-to-perform, low-cost, widely available and non-invasive biomarker for distinguishing between healthy individuals and AD patients.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    自闭症谱系障碍(ASD)是一种异质性、早期发作的神经发育状况,其特征是社交互动和交流持续受损。本研究旨在基于个体灰质脑网络来描述ASD亚型,并从图论的角度提供新的见解。在这项研究中,我们提取并归一化了单主体灰质网络,并计算了每个网络的拓扑属性。通过判别分析(HYDRA)方法的异质性用于基于网络属性的所有患者亚型。接下来,我们探讨了ASD亚型在网络特性和临床测量方面的差异.我们的调查确定了三种不同的ASD亚型。在病例对照研究中,这些亚型表现出显著差异,特别是在中央前回,舌回,和中额回.在案例分析中,在任何两种亚型之间观察到全局和节点属性的显着差异。临床上,与亚型3相比,亚型1显示较低的VIQ和PIQ,但与亚型2相比,ADOS-Communication和ADOS-Total得分较高.结果突出了不同亚型男性ASD患者的不同脑网络特性和行为,为ASD异质性背后的神经机制提供有价值的见解。
    Autism spectrum disorder (ASD) is a heterogeneous, early-onset neurodevelopmental condition characterized by persistent impairments in social interaction and communication. This study aims to delineate ASD subtypes based on individual gray matter brain networks and provide new insights from a graph theory perspective. In this study, we extracted and normalized single-subject gray matter networks and calculated each network\'s topological properties. The heterogeneity through discriminative analysis (HYDRA) method was utilized to subtype all patients based on network properties. Next, we explored the differences among ASD subtypes in terms of network properties and clinical measures. Our investigation identified three distinct ASD subtypes. In the case-control study, these subtypes exhibited significant differences, particularly in the precentral gyrus, lingual gyrus, and middle frontal gyrus. In the case analysis, significant differences in global and nodal properties were observed between any two subtypes. Clinically, subtype 1 showed lower VIQ and PIQ compared to subtype 3, but exhibited higher scores in ADOS-Communication and ADOS-Total compared to subtype 2. The results highlight the distinct brain network properties and behaviors among different subtypes of male patients with ASD, providing valuable insights into the neural mechanisms underlying ASD heterogeneity.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    脑内功能定位的概念以及在切除浸润性肿瘤期间切除这些区域的相关风险,如弥漫性神经胶质瘤,在神经外科中很成熟。全局效率(GE)是可用于模拟肿瘤切除后的连接体破坏的图论概念。结构连通性图是从80名健康成年人的大脑获得的扩散束造影图创建的。然后,通过识别图中相邻节点的每种可能组合,然后测量节点缺失后GE的下降,将这些图用于模拟大脑每个大体解剖区域的切片切除。逐步消除大脑分裂导致GE下降的模式,这是可以合理预测的,但具有受试者之间的差异。此外,正如预期的那样,删除了一些比其他节点更糟糕的节点。然而,在每个受试者检查的每个肺叶中,对于GE,一些缺失组合比在大脑不同区域中去除更多数量的节点更糟糕.在某些患者中,移除时表现出最差GE的常见节点的模式被识别为“连接类型”。鉴于文献中的一些证据将GE与神经认知能力的某些方面联系起来,研究这些连接类型可能会减轻脑外科手术对认知的影响.
    The concept of functional localization within the brain and the associated risk of resecting these areas during removal of infiltrating tumors, such as diffuse gliomas, are well established in neurosurgery. Global efficiency (GE) is a graph theory concept that can be used to simulate connectome disruption following tumor resection. Structural connectivity graphs were created from diffusion tractography obtained from the brains of 80 healthy adults. These graphs were then used to simulate parcellation resection in every gross anatomical region of the cerebrum by identifying every possible combination of adjacent nodes in a graph and then measuring the drop in GE following nodal deletion. Progressive removal of brain parcellations led to patterns of GE decline that were reasonably predictable but had inter-subject differences. Additionally, as expected, there were deletion of some nodes that were worse than others. However, in each lobe examined in every subject, some deletion combinations were worse for GE than removing a greater number of nodes in a different region of the brain. Among certain patients, patterns of common nodes which exhibited worst GE upon removal were identified as \"connectotypes\". Given some evidence in the literature linking GE to certain aspects of neuro-cognitive abilities, investigating these connectotypes could potentially mitigate the impact of brain surgery on cognition.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    背景:尽管减少肉类消费在西方国家越来越受欢迎,这种向可持续饮食的过渡可能会带来一些营养风险。
    目的:我们旨在分析达到低肉健康饮食的途径以及快速减少红肉总消费量所需的其他食品类别的变化。
    方法:我们使用了一种基于图论的最近开发的方法来表示所有可能的逐步变化途径,以避免营养缺乏,从而达到目标健康饮食。初始和目标饮食被定义为33个食物组的每日消费量。对于每个性别,来自法国代表性调查INCA3的三种初始饮食作为平均观察饮食和低(第一五分之一)和高(第五五分之一)肉类消费。使用多标准优化确定目标饮食,以最大程度地减少慢性疾病的长期健康风险,同时确保营养充足。Dijkstra算法用于确定初始饮食和目标饮食之间的最佳途径,目的是尽快减少肉类消费,从而最大限度地减少长期健康风险。
    结果:未加工的红肉在途径的第一步中很容易被最小化,无论性别和最初的肉类消费水平如何。然而,加工肉只能在以后减少,并且需要事先改变,例如增加水果,蔬菜,油腻的鱼在女性红肉总量最小化的过程中,确保足够的生物可利用铁的摄入对所需的其他饮食变化产生了最大的影响.
    结论:通过避免任何营养缺乏的健康饮食,可以立即减少红肉消费。然而,早期增加水果,蔬菜,在饮食早期尽量减少红肉总量之前,需要鱼。
    BACKGROUND: Although reducing meat consumption is becoming increasingly popular in Western countries, such a transition to a sustainable diet can pose some nutritional risks.
    OBJECTIVE: We aim to analyze the pathways for reaching a low-meat healthy diet and the changes in other food categories needed to rapidly decrease total red meat consumption.
    METHODS: We used a recently developed method based on graph theory to represent all possible pathways of stepwise changes that avoid nutritional deficiencies toward a target healthy diet. Initial and target diets were defined as the daily consumption of 33 food groups. For each sex, three initial diets were taken from the French representative survey INCA3 as the mean observed diet and low (first quintile) and high (fifth quintile) meat consumption. Target diets were identified using multi-criteria optimization to minimize the long-term health risk of chronic diseases while ensuring nutritional adequacy. The Dijkstra algorithm was used to identify the optimal pathways between the initial and target diets, with the aim of reducing meat consumption as quickly as possible and thus minimizing long-term health risks.
    RESULTS: Unprocessed red meat was easily minimized in the first steps of the pathways regardless of sex and initial level of meat consumption. However, processed meat could only be decreased later and required prior changes such as increases in fruit, vegetables, and oily fish. During total red meat minimization in females, securing adequate intakes of bioavailable iron had the most substantial impact on the other dietary changes needed.
    CONCLUSIONS: Immediate reduction of red meat consumption is possible on the pathway to a healthy diet that avoids any nutrient deficiency. However, early increases in fruit, vegetables, and fish are required before minimizing total red meat early in the diet.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号