multivariate analysis

多变量分析
  • 文章类型: Journal Article
    几何中位数,适用于高维数据,可以看作是一维数据中使用的单变量中位数的概括。它可以用作识别多维数据位置的鲁棒估计器,在现实场景中具有广泛的应用。本文探讨了使用几何中位数进行高维多变量方差分析(MANOVA)的问题。引入了一种最大类型的统计量,该统计量依赖于各组之间的几何中位数之间的差异。新检验统计量的分布是在零假设下使用高斯近似得出的,并建立了其在替代假设下的一致性。为了近似新统计量在高维的分布,提出了一种野生引导算法,并在理论上证明了这一点。通过在各种维度上进行的模拟研究,样本大小,和数据生成模型,我们演示了基于几何中位数的MANOVA方法的有限样本性能。此外,我们实现了提出的方法来分析乳腺癌基因表达数据集。
    The geometric median, which is applicable to high-dimensional data, can be viewed as a generalization of the univariate median used in 1-dimensional data. It can be used as a robust estimator for identifying the location of multi-dimensional data and has a wide range of applications in real-world scenarios. This paper explores the problem of high-dimensional multivariate analysis of variance (MANOVA) using the geometric median. A maximum-type statistic that relies on the differences between the geometric medians among various groups is introduced. The distribution of the new test statistic is derived under the null hypothesis using Gaussian approximations, and its consistency under the alternative hypothesis is established. To approximate the distribution of the new statistic in high dimensions, a wild bootstrap algorithm is proposed and theoretically justified. Through simulation studies conducted across a variety of dimensions, sample sizes, and data-generating models, we demonstrate the finite-sample performance of our geometric median-based MANOVA method. Additionally, we implement the proposed approach to analyze a breast cancer gene expression dataset.
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  • 文章类型: Journal Article
    空腹血糖(FBG)是公认的缺血性卒中的危险因素,但是很少有研究研究FBG之间的相互作用,血小板分布宽度(PDW)和神经元损伤的严重程度。因此,本研究构建了一个适度的中介模型,旨在阐明FBG之间的关系,PDW,急性缺血性卒中(AIS)患者的NIHSS评分。
    我们对431例AIS患者进行了横断面研究。入院后,我们评估了患者的NIHSS评分,并采集血样测量FBG和PDW水平.通过线性曲线拟合分析PDW调节的FBG与NIHSS评分的关系,多元线性回归分析,并分别进行了调解分析。
    在基于FBG的三元分组中,AIS患者的PDW和NIHSS评分均显示与FBG水平升高相对应的增加(两者均p<0.001).多元线性回归分析表明,FBG和NIHSS评分之间的关系的β系数(95%CI)为1.49(1.27-1.71,p<0.01).FBG和PDW之间关系的β系数(95%CI)为0.02(0.01-0.04,p<0.01)。同样,对于PDW和NIHSS得分之间的关系,调整后的β系数(95%CI)为4.33(3.07-5.59,p<0.01)。这些正关联在敏感性分析和层次分析中保持一致。平滑图表明FBG与PDW和NIHSS评分之间分别存在线性关系。进一步的中介分析表明,PDW显著增加(p<0.01)介导了5.91%的FBG相关NIHSS评分增加。
    这项研究表明,FBG水平与NIHSS评分相关,FBG相关的神经功能缺损可能部分由PDW介导。这些发现强调了监测AIS患者FBG和PDW水平的重要性。潜在的指导性风险干预策略。
    UNASSIGNED: Fasting blood glucose (FBG) is a recognized risk factor for Ischemic Stroke, but little research has examined the interaction among FBG, Platelet Distribution Width (PDW) and the severity of neuronal damage. Thus, the present study constructs a moderated mediation model aimed to elucidate the relationships among FBG, PDW, and NIHSS scores in patients with acute ischemic stroke (AIS).
    UNASSIGNED: We conducted a cross-sectional study on 431 AIS patients. Upon hospital admission, we assessed the patients\' NIHSS scores and collected blood samples to measure FBG and PDW levels. The relationship between FBG and NIHSS scores moderated by PDW was analyzed by linear curve fitting analysis, multiple linear regression analysis, and moderated mediation analysis respectively.
    UNASSIGNED: In the tertile grouping based on FBG, both PDW and NIHSS scores of AIS patients demonstrated an increase corresponding with rising levels of FBG (p<0.001 for both). Multiple linear regression analysis revealed that, the β coefficients (95% CI) for the relationship between FBG and NIHSS scores were 1.49 (1.27-1.71, p<0.01) post-adjustment for potential confounders. The β coefficients (95% CI) for the relationship between FBG and PDW were 0.02 (0.01-0.04, p<0.01) post-adjustment. Likewise, for the relationship between PDW and NIHSS scores, the β coefficients (95% CI) were 4.33 (3.07-5.59, p<0.01) after adjustment. These positive association remained consistent in sensitivity analysis and hierarchical analysis. Smoothed plots suggested that there are linear relationships between FBG and PDW and NIHSS scores respectively. Further mediation analysis indicated that increased PDW significantly (p<0.01) mediated 5.91% of FBG-associated increased NIHSS scores.
    UNASSIGNED: This study suggested that FBG levels were associated with NIHSS scores, and the FBG-associated neurological impairment may be partially mediated by PDW. These findings underscore the importance of monitoring FBG and PDW levels in AIS patients, potentially guiding risk intervention strategies.
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  • 文章类型: Journal Article
    在本文中,我们介绍了一种创新的多变量数据融合策略,用于自适应稳态检测,专门为氧化铝蒸发过程。这种方法旨在抵消由于生产条件的频繁变化而经常引起的生产不稳定性。我们策略的核心是应用基于高斯滤波器的自适应去噪算法,它巧妙地从所选变量中消除错误数据,而不会损害原始信号的保真度。随后,我们实施了多变量R检验方法,与自适应高斯滤波器集成,通过数据融合进行彻底和精确的稳态检测。使用来自工业过程的实际数据严格验证了该方法的效率。我们的发现表明,这种策略显着提高了氧化铝蒸发过程的稳定性和效率(10%),从而为该领域提供了实质性的贡献。此外,这种方法的多功能性表明其在广泛的工业环境中的潜在适用性,在类似的生产挑战盛行的地方。这项研究不仅推进了过程控制领域,而且强调了自适应策略在管理复杂,变量驱动的工业运营。
    In this paper, we introduce an innovative multivariable data fusion strategy for adaptive steady-state detection, specifically tailored for the alumina evaporation process. This approach is designed to counteract the production instabilities that often arise from frequent alterations in production conditions. At the core of our strategy is the application of an adaptive denoising algorithm based on the Gaussian filter, which adeptly eliminates erroneous data from selected variables without compromising the fidelity of the original signal. Subsequently, we implement a multivariable R-test methodology, integrated with the adaptive Gaussian filter, to conduct a thorough and precise steady-state detection via data fusion. The efficiency of this method is rigorously validated using actual data from industrial processes.Our findings reveal that this strategy markedly enhances the stability and efficiency (by 10%) of the alumina evaporation process, thereby offering a substantial contribution to the field. Moreover, the versatility of this approach suggests its potential applicability in a wide range of industrial settings, where similar production challenges prevail. This study not only advances the domain of process control but also underscores the significance of adaptive strategies in managing complex, variable-driven industrial operations.
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  • 文章类型: Journal Article
    幼儿时期标志着执行功能成熟的关键时期,有意识地调节行为和思想的认知能力。基于正念的干预措施已显示出增强儿童执行功能的希望。本研究采用功能近红外光谱技术探讨正念训练对幼儿的影响。收集了68名儿童(41名男孩,年龄为61.8±10.7个月),随机分配到干预组(N=37,年龄为60.03±11.14个月)或对照组(N=31,年龄为59.99±10.89个月)。使用多变量和多尺度样本熵分析。结果表明:(1)干预组在所有三个执行功能任务中接受基于正念的干预后,大脑复杂性降低(ps<0.05),提示干预后神经加工机制更有效;(2)干预组和对照组的差异比较显示,在认知移位(左背外侧前额叶皮层和内侧前额叶皮层)和工作记忆任务(左背外侧前额叶皮层)期间,相关脑区存在显著差异,这证实了干预组行为结果的改善(Z=-3.674,认知转移P<0.001;Z=2.594,工作记忆P<0.01)。这些发现提高了我们对幼儿早期大脑发育的理解,并强调了基于正念的干预影响执行功能的神经机制。对早期干预促进幼儿大脑发育的意义也有所阐述。
    Early childhood marks a pivotal period in the maturation of executive function, the cognitive ability to consciously regulate actions and thoughts. Mindfulness-based interventions have shown promise in bolstering executive function in children. This study used the functional near-infrared spectroscopy technique to explore the impact of mindfulness-based training on young children. Brain imaging data were collected from 68 children (41 boys, aged 61.8 ± 10.7 months) who were randomly assigned to either an intervention group (N = 37, aged 60.03 ± 11.14 months) or a control group (N = 31, aged 59.99 ± 10.89 months). Multivariate and multiscale sample entropy analyses were used. The results showed that: (1) brain complexity was reduced in the intervention group after receiving the mindfulness-based intervention in all three executive function tasks (ps < 0.05), indicating a more efficient neural processing mechanism after the intervention; (2) difference comparisons between the intervention and control groups showed significant differences in relevant brain regions during cognitive shifting (left dorsolateral prefrontal cortex and medial prefrontal cortex) and working memory tasks (left dorsolateral prefrontal cortex), which corroborates with improved behavioral results in the intervention group (Z = -3.674, P < 0.001 for cognitive shifting; Z = 2.594, P < 0.01 for working memory). These findings improve our understanding of early brain development in young children and highlight the neural mechanisms by which mindfulness-based interventions affect executive function. Implications for early intervention to promote young children\'s brain development are also addressed.
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  • 文章类型: Journal Article
    本研究全面调查了高温烹饪(HT)的影响,复合酶水解(CE),和高温蒸煮联合酶解(HE)对化学成分的影响,微观结构,从玉米麸皮中提取的可溶性膳食纤维(SDF)的功能特性。结果表明,HE-SDF产量最高,为13.80±0.20g/100g,随着热稳定性的增强,粘度,水化特性,吸附能力,和抗氧化活性。聚类分析揭示了SDF的三个不同类别的理化性质。主成分分析(PCA)证实了HE-SDF的优良功能性质。相关分析显示单糖组成之间呈正相关关系,纯度,和SDF的粘度及其大部分功能属性,而颗粒大小和zeta电位呈负相关。此外,在结晶度和热性能之间观察到高度显著的正相关。这些发现表明,HE方法构成了提高源自玉米麸皮的SDF质量的可行策略。
    This study comprehensively investigated the effects of high-temperature cooking (HT), complex enzyme hydrolysis (CE), and high-temperature cooking combined enzymatic hydrolysis (HE) on the chemical composition, microstructure, and functional attributes of soluble dietary fiber (SDF) extracted from corn bran. The results demonstrated that HE-SDF yielded the highest output at 13.80 ± 0.20 g/100 g, with enhancements in thermal stability, viscosity, hydration properties, adsorption capacity, and antioxidant activity. Cluster analysis revealed three distinct categories of SDF\'s physicochemical properties. Principal component analysis (PCA) confirmed the superior functional properties of HE-SDF. Correlation analysis showed positive relationships between the monosaccharide composition, purity, and viscosity of SDF and most of its functional attributes, whereas particle size and zeta potential were inversely correlated. Furthermore, a highly significant positive correlation was observed between crystallinity and thermal properties. These findings suggest that the HE method constitutes a viable strategy for enhancing the quality of SDF sourced from corn bran.
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  • 文章类型: English Abstract
    Objective: To understand the occupational stress and mental health status of hospital infection prevention and control practitioner (HIPCPs) in medical institutions, and analyze their main influencing factors. Methods: In November 2021, 550 nosocomial infection managers in Tianjin were randomly selected to conduct a questionnaire survey using the Concise Occupational Stress Questionnaire, Depression Screening Scale (PHQ-9) and Self-Rating Anxiety Scale (SAS). 497 valid questionnaires were obtained, and the total recovery efficiency was 90.36%. Single factor analysis and multivariate logistic regression method were used to analyze the main influencing factors of occupational stress and mental health status of psychiatric managers. Results: The detection rate of anxiety and depression among 497 HIPCPs was 22.73% (113/497) and 58.95% (293/497), respectively. Gender and major were the influencing factors of depression (P=0.000, 0.001). Average working hours>52 hours per week and night shift days>1 days per week were the influencing factors of anxiety (P=0.035, 0.014). Average working hours>52 h per week, night shift days >1 d per week and different majors were the influencing factors of occupational stress (P=0.000, 0.025, 0.010). Multivariate logistic regression results showed that the risk of anxiety in those who worked more than 52 hours per week was 1.753 times that of those who worked less than 52 hours per week (P=0.038), and the risk of depression in women was 3.071 times that of men (P=0.006) . Conclusion: Working hours are an important influencing factor for occupational stress and anxiety among HIPCPs. In order to reduce the occurrence of occupational stress and mental health problems, it is necessary to strengthen psychological counseling for HIPCPs and balance work and rest.
    目的: 了解医疗机构医院感染管理人员的职业应激和心理健康状况,并分析其主要影响因素。 方法: 于2021年11月,随机选择天津市550名医院感染管理人员,使用《简明职业紧张问卷》《抑郁筛查量表》(PHQ-9)和《焦虑自评量表》(SAS)开展问卷调查。回收有效问卷497份,总回收有效率为90.36%。使用单因素分析和多因素非条件logistic回归方法分析院感管理人员职业应激和焦虑及抑郁的主要影响因素。 结果: 497名医院感染管理人员焦虑和抑郁检出率分别为22.73%(113/497)和58.95%(293/497)。性别、不同专业是抑郁的影响因素(P=0.000、0.001);平均每周工作时长>52 h和每周夜班天数>1 d是焦虑的影响因素(P=0.035、0.014);平均每周工作时长>52 h、每周夜班天数>1 d、不同专业是职业应激的影响因素(P=0.000、0.025、0.010)。多因素logistic回归结果显示,平均每周工作时长>52 h者发生焦虑的风险是平均每周工作时长≤52 h者的1.753倍(P=0.038),女性发生抑郁的风险是男性的3.071倍(P=0.006)。 结论: 工作时长是医院感染管理人员产生职业应激和焦虑的重要影响因素,应加强对医院感染管理人员的心理疏导,注意劳逸结合,以减少职业应激和心理健康问题的发生。.
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  • 文章类型: Letter
    暂无摘要。
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  • 文章类型: English Abstract
    OBJECTIVE: To establish a model to predict the overall survival (OS) rate of patients with diffuse large B-cell lymphoma (DLBCL) based on systemic inflammatory indicators, and study whether the new model combined with inflammatory related parameters is more effective than the conventional model using only clinical factors to predict the OS of patients with DLBCL.
    METHODS: The clinical data of 213 patients with DLBCL were analyzed retrospectively. Backward stepwise Cox regression analysis was used to screen independent prognostic factors related to OS, and a nomogram for predicting OS was constructed based on these factors. Akaike information criterion (AIC) and Bayesian information criterion (BIC) were used to evaluate the fitting of the model, the consistency index (C-index), area under receiver operating characteristic (ROC) curve (AUC) and calibration curve were used to evaluate the prediction accuracy of nomogram, and decision curve analysis (DCA) and Kaplan Meier curve were used to evaluate the clinical practicability of nomogram.
    RESULTS: Multivariate analysis confirmed that age, ECOG PS score, serum lactate dehydrogenase (LDH) level, systemic immune inflammatory index (SII), and prognostic nutritional index (PNI) were used to construct the nomogram. The AIC and BIC of the nomogram were lower than the International Prognostic Index (IPI) and the National Comprehensive Cancer Network (NCCN)-IPI, indicating that the nomogram had better goodness of fit. The C-index and AUC of the nomogram were higher than IPI and NCCN-IPI, indicating that the prediction accuracy of the nomogram had been significantly improved, and the calibration curve showed that the prediction results were in good agreement with the actual survival results. DCA showed that the nomogram had better clinical net income. Kaplan Meier curve showed that patients could be well divided into low-risk, medium-risk and high-risk groups according to the nomogram score (P < 0.001).
    CONCLUSIONS: The nomogram combined with inflammatory indicators can accurately predict the individual survival probability of DLBCL patients.
    UNASSIGNED: 系统性炎症指标可以改善弥漫大B细胞淋巴瘤患者的生存预测:模型的开发和评价.
    UNASSIGNED: 基于全身炎症指标建立一个用于预测弥漫大B细胞淋巴瘤(DLBCL)患者总生存(OS)率的模型,并研究结合炎症相关参数的新模型是否比仅使用临床因素的常规模型能更有效地预测DLBCL患者的OS。.
    UNASSIGNED: 回顾性分析了213例DLBCL患者的临床数据,向后逐步Cox回归分析筛选与OS相关的独立预后因素,基于这些因素构建预测OS的列线图。使用Akaike信息准则(AIC)和Bayesian信息准则(BIC)评估模型的拟合情况,一致性指数、受试者工作特征曲线下面积(AUC)和校准曲线评估列线图的预测准确性,使用决策曲线分析和Kaplan-Meier曲线评估列线图的临床实用性。.
    UNASSIGNED: 多变量分析确定年龄、美国东部合作组体能状态评分、血清乳酸脱氢酶水平、全身免疫炎症指数、预后营养指数用于构建列线图。列线图的AIC和BIC低于国际预后指数(IPI)和美国国家综合癌症网络(NCCN)-IPI,表明列线图具有更好的拟合优度。列线图的一致性指数和AUC高于IPI和NCCN-IPI,表明列线图的预测准确性明显改善,校准曲线显示出预测结果和实际生存结果具有良好的一致性。决策曲线分析显示列线图具有更好的临床净收益。Kaplan-Meier曲线显示,根据列线图评分可以很好地将患者分为低危、中危、高危三个风险组(P < 0.001)。.
    UNASSIGNED: 结合炎症指标的列线图可以准确地预测DLBCL患者个体化的生存概率。.
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  • 文章类型: Journal Article
    背景:Alactic碱过量(ABE)是一种新的生物标志物,用于评估肾脏处理酸碱紊乱的能力,已发现这与脓毒症和休克患者的不良预后有关。本研究旨在评估急性心肌梗死(AMI)患者ABE与院内死亡风险之间的关系。
    方法:本回顾性队列研究从重症监护医学信息集市(MIMIC)-IV数据库收集AMI患者的临床数据。结果是重症监护病房(ICU)入院后的住院死亡率。单变量和多变量Cox比例风险模型用于评估ABE与AMI患者住院死亡率的相关性。风险比(HR)和95%置信区间(CI)。为了进一步探索该协会,根据年龄进行亚组分析,AKI,eGFR,脓毒症,和AMI亚型。
    结果:在总共2779例AMI患者中,502人在医院死亡。阴性ABE(HR=1.26,95CI:1.02-1.56)(中性ABE作为参考)与AMI患者住院死亡风险较高相关。但ABE不阳性(P=0.378)。亚组分析显示,在年龄>65岁的AMI患者中,ABE阴性与院内死亡风险较高显著相关(HR=1.46,95CI:1.13-1.89),eGFR<60(HR=1.35,95CI:1.05-1.74),AKI(HR=1.32,95CI:1.06-1.64),ST段抬高型急性心肌梗死(STEMI)亚型(HR=1.79,95CI:1.18-2.72),无脓毒症(HR=1.29,95CI:1.01-1.64)。
    结论:ABE阴性与AMI患者的住院死亡率显著相关。
    BACKGROUND: Alactic base excess (ABE) is a novel biomarker to evaluate the renal capability of handling acid-base disturbances, which has been found to be associated with adverse prognosis of sepsis and shock patients. This study aimed to evaluate the association between ABE and the risk of in-hospital mortality in patients with acute myocardial infarction (AMI).
    METHODS: This retrospective cohort study collected AMI patients\' clinical data from the Medical Information Mart for Intensive Care (MIMIC)-IV database. The outcome was in-hospital mortality after intensive care unit (ICU) admission. Univariate and multivariate Cox proportional hazards models were performed to assess the association of ABE with in-hospital mortality in AMI patients, with hazard ratios (HRs) and 95% confidence intervals (CI). To further explore the association, subgroup analyses were performed based on age, AKI, eGFR, sepsis, and AMI subtypes.
    RESULTS: Of the total 2779 AMI patients, 502 died in hospital. Negative ABE (HR = 1.26, 95%CI: 1.02-1.56) (neutral ABE as reference) was associated with a higher risk of in-hospital mortality in AMI patients, but not in positive ABE (P = 0.378). Subgroup analyses showed that negative ABE was significantly associated with a higher risk of in-hospital mortality in AMI patients aged>65 years (HR = 1.46, 95%CI: 1.13-1.89), with eGFR<60 (HR = 1.35, 95%CI: 1.05-1.74), with AKI (HR = 1.32, 95%CI: 1.06-1.64), with ST-segment elevation acute myocardial infarction (STEMI) subtype (HR = 1.79, 95%CI: 1.18-2.72), and without sepsis (HR = 1.29, 95%CI: 1.01-1.64).
    CONCLUSIONS: Negative ABE was significantly associated with in-hospital mortality in patients with AMI.
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  • 文章类型: Journal Article
    背景:重症监护病房(ICU)的患者极易营养不良,虽然通过鼻胃管进行肠内营养是首选方法,有无意的反流和误吸的风险。因此,临床医生已将鼻肠管(NET)作为肠内营养的替代选择。但是NET的精确定位提出了一个持续的挑战。我们提出了一种创新的方法,为参与NET放置的临床医生提供有价值的参考。
    方法:数据来自2017年10月1日至2023年10月1日期间在浙江省人民医院ICU接受NET治疗的误吸或胃喂养不耐受风险高的成年患者的病历。使用SPSS和R软件对收集的数据进行统计分析。
    结果:494例患者符合纳入和排除标准。首过成功率为81.4%(n=402)。发现患者初始NET放置的成功与角度SPC和距离CP有关,通过单变量分析确定(25.6±16.7°与41.9±18.0°,P<0.001;40.0±26.2mmvs.62.0±31.8mm,分别为P<0.001)。通过进行多元回归分析,我们发现幽门类型与NET置入成功率之间存在显著关联(OR29.559,95CI14.084-62.038,P<0.001).
    结论:角度SPC,距离CP,和幽门的类型与NET的成功初始放置独立相关。此外,幽门外侧型(OP型)患者的初始安置成功率较高.
    BACKGROUND: Patients in the intensive care unit (ICU) are highly susceptible to malnutrition, and while enteral nutrition via nasogastric tube is the preferred method, there is a risk of inadvertent reflux and aspiration. Therefore, clinicians have turned to nasointestinal tubes (NET) for enteral nutrition as an alternative option. But the precise localization of NET presents an ongoing challenge. We proposed an innovative approach to provide a valuable reference for clinicians involved in NET placement.
    METHODS: Data were obtained retrospectively from the medical records of adult patients with a high risk of aspiration or gastric feeding intolerance who had a NET placed in the ICU of Zhejiang Provincial People\'s Hospital between October 1, 2017, and October 1, 2023. The collected data were subjected to statistical analysis using SPSS and R software.
    RESULTS: There were 494 patients who met the inclusion and exclusion criteria. The first-pass success rate was 81.4% (n = 402). The success of a patient\'s initial NET placement was found to be associated with Angle SPC and Distance CP, as determined by univariate analysis (25.6 ± 16.7° vs. 41.9 ± 18.0°, P < 0.001; 40.0 ± 26.2 mm vs. 62.0 ± 31.8 mm, P < 0.001, respectively). By conducting a multivariate regression analysis, we identified a significant association between pyloric types and the success rate of placing NET (OR 29.559, 95%CI 14.084-62.038, P < 0.001).
    CONCLUSIONS: Angle SPC, Distance CP, and the type of pylorus are independently associated with successful initial placement of NET. Besides, patients with the outside type of pylorus (OP-type) exhibit a higher rate of initial placement success.
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