Linear correlation

线性相关
  • 文章类型: Journal Article
    本研究旨在从微观水平研究竹材的梯度特性,为提高竹材的利用率提供依据。使用毛竹(Phyllostachysedulis(Carrère)J.Houz。)作为一个研究课题,血管束面积百分比的变化,化学成分,相对结晶度(CR),不同竹条的力学性能,并分析了这些参数之间的相关性。从竹绿色层(BGL)到竹黄色层(BYL),维管束分布由密集变为稀疏。纤维素和木质素质量含量温和下降,半纤维素质量含量逐渐增加。CR显示竹子中间层(BML)>BGL>BYL的顺序。拉伸弹性模量,抗拉强度,弯曲弹性模量,弯曲强度从BGL下降到BYL。对毛竹力学性能的影响程度依次为维管束面积,半纤维素含量,木质素质量含量,密度,和CR,这些因素与力学性能有显著的相关性(p<0.05)。维管束面积对竹材的力学性能有决定性影响。维管束面积和密度与力学性能呈线性关系,木质素质量含量和CR与力学性能呈曲线线性相关。
    This study aimed to investigate the gradient properties of bamboo at the microscopic level and provide a basis for improving the utilization rate of bamboo. Using moso bamboo (Phyllostachys edulis (Carrière) J. Houz.) as a research subject, the variation of vascular bundle area percentage, chemical content, relative crystallinity (CR), mechanical properties of different bamboo slivers, and correlation between those parameters were analyzed. From the bamboo green layer (BGL) to the bamboo yellow layer (BYL), the distribution of vascular bundles changed from dense to sparse. Cellulose and lignin mass content decreased gently, and hemicellulose mass content showed gradual increases. The CR showed an order of bamboo middle layer (BML) > BGL > BYL. The tensile modulus of elasticity, tensile strength, bending modulus of elasticity, and bending strength decreased from BGL to BYL. The order of influence degree on mechanical properties of moso bamboo was vascular bundle area, hemicellulose content, lignin mass content, density, and CR, and these factors correlated with mechanical properties at a significant level (p < 0.05). Vascular bundle area had a decisive effect on the mechanical properties of bamboo. The vascular bundle area and density were linearly correlated with mechanical properties, while the lignin mass content and CR were curve-linearly correlated with mechanical properties.
    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
    偏头痛和严重头痛是困扰人类和社会的极为普遍的神经系统疾病。先前的研究表明,DII可能会影响偏头痛的发生,但是相关研究太少,需要更多。本研究旨在确定严重头痛或偏头痛与饮食炎症指数(DII)之间的关系。特别注意年龄和性别差异。
    使用国家健康和营养调查(NHANES)的数据,我们进行了一项横断面研究.此外,我们使用加权多变量逻辑回归模型研究了DII与严重头痛或偏头痛之间的关系,并绘制了有限的三次样条模型来探索它们的线性相关。
    共有13,439人参与了这项研究,其中,2745在过去三个月内经历了严重的头痛或偏头痛。DII与严重头痛或偏头痛呈线性正相关(比值比[OR]=1.05,95%置信区间[CI]=1.01-1.08,p=0.0051)。分层分析表明,这种关系在女性和年龄<60岁的人群中持续存在。ORs为1.08(95%CI=1.04-1.13,p=0.0004)和1.05(95%CI=1.01-1.09,p=0.0071),分别。
    我们发现更高水平的DII与偏头痛发作的可能性增加显著相关,特别是在妇女和中青年人群中。需要进一步的研究来验证和扩展我们的结果。
    UNASSIGNED: Migraine and severe headaches are extremely prevalent neurological disorders that plague humans and society. Prior research has revealed that DII may affect the occurrence of migraines, but there are too few relevant studies and more are required. This study aimed to determine the association between severe headache or migraine and the Dietary Inflammatory Index (DII), with particular attention to age and gender differences.
    UNASSIGNED: Using data from the National Health and Nutrition Examination Survey (NHANES), we performed a cross-sectional study. In addition, we investigated the association between DII and severe headache or migraine using weighted multivariate logistic regression models, and restricted cubic splines models were plotted to explore their linear correlation.
    UNASSIGNED: There were a total of 13,439 people participating in the study, and of those, 2745 experienced a severe headache or migraine within the previous three months. The DII was linearly and positively correlated with severe headache or migraine (odds ratio [OR] = 1.05, 95% confidence interval [CI] = 1.01-1.08, p = 0.0051). Stratified analysis showed that this relationship persisted among women and those aged < 60 years, with ORs of 1.08 (95% CI = 1.04-1.13, p = 0.0004) and 1.05 (95% CI = 1.01-1.09, p = 0.0071), respectively.
    UNASSIGNED: We found that greater levels of DII were significantly related to an increased likelihood of migraine onset, especially among women and young and middle-aged populations. Further research is required to validate and expand upon our results.
    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:研究X线平片上的层间间隙大小与腰椎管狭窄(LSS)之间的相关性。
    方法:本研究包括100例LSS患者和100例无LSS的正常参与者。在平片上测量腰椎层间参数。在CT和MRI上测量椎管参数。在LSS和对照组之间比较这些图像参数。层间参数之间的线性相关性,分析椎管参数和Oswestry残疾指数(ODI)。分析了诊断L3/4和L4/5症状性LSS的层间参数的临界值。
    结果:L1/2层间宽度除外,LSS组的所有椎板间和椎管相关参数均明显小于对照组。除L1/2层间宽度和L5/S1层间高度外,在各个腰椎层面,所有椎间参数与椎管参数均具有显著正线性相关性.对于有症状的LSS的诊断,L4/5层间宽度的截止值,高度和面积为18.46毫米,11.37mm和134.05mm2,而15.78mm,L3/4中的13.59mm和157.98mm2。在L4/5LSS的情况下,椎管大小和椎间大小与ODI没有线性相关。
    结论:X线片上的腰椎层间间隙大小与发育性和退行性LSS呈正线性相关,除L1/2层间宽度和L5/S1层间高度外。腰椎平片可以通过评估层间空间大小来预测和帮助诊断LSS。
    方法:III.
    Investigating the correlation between the interlaminar space size on plain radiograph and lumbar spinal stenosis (LSS).
    100 Patients with LSS and 100 normal participants without LSS were included in this study. Lumbar interlaminar parameters were measured on plain radiographs. Spinal canal parameters were measure on CT and MRI. These image parameters were compared between LSS and control group. The linear correlation among interlaminar parameters, spinal canal parameters and Oswestry Disability Index (ODI) were analyzed. The cut-off values of interlaminar parameters for diagnosing L3/4 and L4/5 symptomatic LSS were analyzed.
    Excepting for L1/2 interlaminar width, all interlaminar and spinal canal related parameters in LSS group were significantly smaller than those in control group. Excepting for L1/2 interlaminar width and L5/S1 interlaminar height, all interlaminar parameters had significantly positive linear correlation with spinal canal parameters accordingly in each lumbar level. For diagnosis of symptomatic LSS, The cut off values of L4/5 interlaminar width, height and area were 18.46 mm, 11.37 mm and 134.05 mm2 while 15.78 mm, 13.59 mm and 157.98 mm2 in L3/4. Both spinal canal size and interlaminar size had no linear correlation with ODI in cases of L4/5 LSS.
    Lumbar interlaminar space size on plain radiograph has positive linear correlation with developmental and degenerative LSS, excepting for L1/2 interlaminar width and L5/S1 interlaminar height. Lumbar plain radiograph can be a feasible way for predicting and helping to diagnose LSS through evaluating the interlaminar space size.
    III.
    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
    The idealized urea electrocatalyst is crucial to boost the CN coupling reaction and simultaneously suppress their isolated reduction process after adsorbing N2 and CO2 molecules. Therefore, the dispersed MN3 -M\'N4 moiety is investigated systematically, including 26 homonuclear and 650 heteronuclear di-metal systems. After, 205 stable systems are selected using lowest-energy principle and ab initio molecular dynamics simulations. According to three possible pathways, NCON, CO, and OCOH to produce urea, a five-step high-throughput screening method for excellent catalytic activity and a five-aspect high-throughput screening strategy for outstanding catalytic selectivity are proposed, respectively. The potential determined steps and the limiting potential through three pathways are identified. The data indicates both CO pathway and OCOH pathway are more competitive at lower Gibbs free energy. Significantly, the most favorite RuN3 -CoN4 combination possesses an extremely low limiting potential of -0.80 V for urea production, meanwhile it exists a strong foundation for experimental preparation. This work not only broadens electrocatalytic potentiality of developing di-metals as two active sites, but also provides a feasible high-throughput screening recipe for urea production.
    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
    尽管已经报道了许多催化剂用于将CO2电还原为C1或C2化学品,对不同产品之间基本相关性的理解不足仍然阻碍了通用催化剂设计策略的发展。在这里,我们首先发现,表面*CO覆盖率在很宽的电位范围内是稳定的,并揭示了CH4和C2产品在这个电位范围内的部分电流密度之间的线性关系,也得到了理论动力学分析的支持。基于*CHO是CH4(*CHO→CH4)和C2(*CHO*CO→C2)形成的共同中间体的机制,然后,我们揭示了这种线性相关是普遍的,斜率可以通过调整表面*H或*CO覆盖率来改变,以促进CH4或C2产物的选择性,分别。作为概念证明,使用碳涂层的铜颗粒,表面*H覆盖率可以增加,以提高CH4的产量,呈现高CO2至CH4的法拉第效率([公式:见正文]52%)和出色的CH4部分电流密度-337mAcm-2。另一方面,使用Ag掺杂的Cu催化剂,CO2RR选择性切换到C2途径,具有79%的基本提升的[公式:参见正文]和-421mAcm-2的高部分电流密度。我们对调节中间覆盖率的发现表明了针对不同CO2电还原途径的强大催化剂设计策略。
    Although many catalysts have been reported for the CO2 electroreduction to C1 or C2 chemicals, the insufficient understanding of fundamental correlations among different products still hinders the development of universal catalyst design strategies. Herein, we first discover that the surface *CO coverage is stable over a wide potential range and reveal a linear correlation between the partial current densities of CH4 and C2 products in this potential range, also supported by the theoretical kinetic analysis. Based on the mechanism that *CHO is the common intermediate in the formation of both CH4 (*CHO → CH4) and C2 (*CHO + *CO → C2), we then unravel that this linear correlation is universal and the slope can be varied by tuning the surface *H or *CO coverage to promote the selectivity of CH4 or C2 products, respectively. As proofs-of-concept, using carbon-coated Cu particles, the surface *H coverage can be increased to enhance CH4 production, presenting a high CO2-to-CH4 Faradaic efficiency ( [Formula: see text] ∼52%) and an outstanding CH4 partial current density of -337 mA cm-2. On the other hand, using an Ag-doped Cu catalyst, the CO2RR selectivity is switched to the C2 pathway, with a substantially promoted [Formula: see text] of 79% and a high partial current density of -421 mA cm-2. Our discovery of tuning intermediate coverages suggests a powerful catalyst design strategy for different CO2 electroreduction pathways.
    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
    UASSIGNED:本研究旨在探讨全膝关节置换术(TKA)后组件排列与短期临床结果之间的相关性。
    未经评估:来自地区医院的50名TKA患者被纳入研究。从手术后1周内获得的放射学数据测量以下组件对齐:髋-膝-踝角度(HKA),股骨远端内侧角(MDFA),胫骨近端内侧角(MPTA),股骨屈伸角度(FEA),胫骨倾斜角(TSA),股骨旋转角(FRA)和胫骨旋转角(TRA)。特殊外科医院(HSS)膝关节评分系统用于评估1年后的临床结果,将患者分为三组(优秀,好和不好)根据HSS分数。统计学分析采用差异分析和线性相关分析。
    UNASSIGNED:结果显示三个患者组之间的MDFA(p=0.050)和FEA(p=0.001)存在显着差异。还发现总HSS与FEA仅具有中等相关性(r=0.572,p<0.001),但FEA与疼痛评分呈正线性相关(r=0.347,p=0.013),函数得分(r=0.535,p=0.000),ROM分数(r=0.368,p=0.009),肌肉评分(r=0.354,p=0.012)和稳定性评分(r=0.312,p=0.028)。较大的MDFA与较低的FE畸形评分相关(r=-0.289,p=0.042),TSA对ROM有积极影响(r=0.436,p=0.002)。此外,FRA的变化导致FE畸形评分随之变化(r=0.312,p=0.027),肌肉力量评分随着TRA的增加而增加(r=0.402,p=0.004)。
    UNASSIGNED:结果表明,FEA在TKA后的临床结局中起着重要作用。手术技术和工具可能需要改进以准确地调整FEA以改善关节功能和患者满意度。
    UNASSIGNED: This study aimed to investigate the correlation between component alignment and short-term clinical outcomes after total knee arthroplasty (TKA).
    UNASSIGNED: 50 TKA patients from a regional hospital were enrolled in the study. The following component alignments were measured from radiological data acquired within 1 week after surgery: hip-knee-ankle angle (HKA), medial distal femoral angle (MDFA), medial proximal tibial angle (MPTA), femoral flexion-extension angle (FEA), tibial slope angle (TSA), femoral rotational angle (FRA) and tibial rotational angle (TRA). The Hospital for Special Surgery (HSS) knee scoring system was used to assess clinical outcomes after 1 year, with patients being divided into three groups (excellent, good and not good) according to the HSS scores. Difference analysis and linear correlation analysis were used for the statistical analysis.
    UNASSIGNED: The results showed significant differences in MDFA (p = 0.050) and FEA (p = 0.001) among the three patient groups. It was also found that the total HSS had only a moderate correlation with FEA (r = 0.572, p < 0.001), but FEA had a positive linear correlation with pain scores (r = 0.347, p = 0.013), function scores (r = 0.535, p = 0.000), ROM scores (r = 0.368, p = 0.009), muscle scores (r = 0.354, p = 0.012) and stability scores (r = 0.312, p = 0.028). A larger MDFA was associated with lower FE deformity scores (r = -0.289, p = 0.042) and the TSA had a positive influence on the ROM (r = 0.436, p = 0.002). Also, changes in FRA produced a consequent change in the FE deformity score (r = 0.312, p = 0.027), and the muscle strength scores increased as TRA increased (r = 0.402, p = 0.004).
    UNASSIGNED: The results show that the FEA plays a significant role in clinical outcomes after TKA. Surgical techniques and tools may need to be improved to accurately adjust the FEA to improve joint functionality and patient satisfaction.
    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
    骨生物力学特性的有效预测在骨质量评估中起着重要作用。然而,本技术对于临床应用而言具有低准确性或高复杂性。本研究旨在研究进化卷积神经网络(CNN)技术在预测多孔骨骼结构的有效压缩模量方面的预测能力。使用HR-pQCT扫描仪扫描了35具女性尸体的T11/T12/L1段,并将从中获得的图像用于生成108962D骨样本,其中仅处理和研究了松质骨部分。生成了相应的10896个异质有限元(FE)模型,然后使用FE分析的预测作为地面事实来构建和训练CNN模型。然后使用从初始HR-pQCT图像生成的剩余260个骨样本来测试CNN模型的预测能力。结果表明,CNN和FE预测弹性模量之间的线性相关性的行列式系数(R2)为0.95,远高于BMD和FE预测之间的相关性(R2=0.65)。此外,相对预测误差的第95百分位数和第50百分位数分别低于0.28和0.09。在结论中,CNN模型可以有效预测人松质骨的有效压缩模量,可作为一种有前途且临床适用的多孔骨力学质量评价方法。
    The efficient prediction of biomechanical properties of bone plays an important role in the assessment of bone quality. However, the present techniques are either of low accuracy or of high complexity for the clinical application. The present study aims to investigate the predictive ability of the evolving convolutional neural network (CNN) technique in predicting the effective compressive modulus of porous bone structures. The T11/T12/L1 segments of thirty-five female cadavers were scanned using the HR-pQCT scanner and the images obtained from it were used to generate 10896 2 D bone samples, in which only the cancellous bony parts were processed and investigated. The corresponding 10896 heterogeneous finite-element (FE) models were generated, and then a CNN model was constructed and trained using the predictions of the FE analysis as the ground truths. Then the remaining 260 bone samples generated from the initial HR-pQCT images were used to test the predictive power of the CNN model. The results show that the coefficient of the determinant (R2) from the linear correlation between the CNN and FE predicted elastic modulus is 0.95, which is much higher than that from the correlation between the BMD and the FE predictions (R2 = 0.65). Furthermore, the 95th and 50th percentiles of relative prediction error are below 0.28 and 0.09, respectively. In the conclusion, the CNN model can efficiently predict the effective compressive modulus of human cancellous bone and can be used as a promising and clinically applicable method to evaluate the mechanical quality of porous bone.
    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
    含淀粉食品的许多特性在统计上与各种结构参数显着相关。相关性的重要性由p值判断,这种评估是基于结构参数和性能之间的线性关系的假设。我们在这里检查了线性假设,看看它是否可以用来预测与测量条件不接近的条件下的属性。为此,我们使用了常见的驯化水稻(DR)和澳大利亚野生水稻(AWR),与DR相比,后者具有明显不同的结构参数和性能。结果表明:(1)不仅受支链淀粉或直链淀粉链长分布或直链淀粉含量的控制,其他结构特征也很重要,(2)线性模型可以从结构参数在一定程度上预测AWRs和DR的焓ΔHg,但通常不准确;它可以从链长分布和较长直链淀粉链(聚合度>500)的数量,以可接受的精度预测rice的ΔHg。和(3)线性模型可以预测AWR和DR的粘性到可接受的精度方面较长的直链淀粉链的量。因此,如果还用于定量预测,则需要谨慎地考虑结构-性质相关性的常用线性假设。
    Many properties of starch-containing foods are significantly statistically correlated with various structural parameters. The significance of a correlation is judged by the p-value, and this evaluation is based on the assumption of linear relationships between structural parameters and properties. We here examined the linearity assumption to see if it can be used to predict properties at conditions that are not close to those under which they were measured. For this we used both common domesticated rices (DRs) and Australian wild rices (AWRs), the latter having significantly different structural parameters and properties compared to DRs. The results showed that (1) the properties were controlled by more than just the amylopectin or amylose chain-length distributions or amylose content, other structural features also being important, (2) the linear model can predict the enthalpy ΔHg of both AWRs and DRs from the structural parameters to some extent but is often not accurate; it can predict the ΔHg of indica rices with acceptable accuracy from the chain length distribution and the amount of longer amylose chains (degree of polymerization > 500), and (3) the linear model can predict the stickiness of both AWRs and DRs to acceptable accuracy in terms of the amount of longer amylose chains. Thus, the commonly used linearity assumption for structure-property correlations needs to be regarded circumspectly if also used for quantitative prediction.
    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
    金刚烷胺,一种抗病毒药物,已广泛应用于人类抗流感治疗。然而,几种高致病性禽流感病毒在病毒基质2(M2)蛋白中显示金刚烷胺抗性突变。在这里,我们分析了全球H5N1测序数据,并计算了M2中关键突变频率与死亡率之间可能的相关性。我们发现M2(从人类和鸟类宿主中分离)中L26I/V27A突变的频率与人类H5N1感染的死亡率呈线性关系。禽类中的M2突变与人类死亡率之间的显着相关性表明,禽类中L26I/V27A的预先存在可能决定了从禽类到人类宿主的传播感染后的患者死亡。L26I/V27A突变的100%患病率使死亡率从51%(95%置信区间[CI]37%-65%)增加到89%(95%CI88%-90%)。涉及Leu26或Val27的突变被鉴定为来自药物选择压力的主要突变。因此,死亡率超过90%的超级H5N1病毒的出现可能归因于在家禽中滥用金刚烷胺,特别是在一些东南亚国家。必须对抗病毒兽药进行更严格的控制。
    Amantadine, an antiviral drug, has been widely used in human anti-influenza treatments. However, several highly pathogenic avian influenza viruses show amantadine-resistance mutations in the viral matrix 2 (M2) protein. Here we analyzed global H5N1 sequencing data and calculate possible correlations between frequencies of key mutations in M2 and the mortality rates. We found that the frequency of L26I/V27A mutation in M2 (isolated from both human and avian hosts) is linearly correlated with the mortality rates of human H5N1 infections. The significant correlation between M2 mutations in avians and the mortality rates in humans suggests that the pre-existence of L26I/V27A in birds may determine patient fatalities after transinfections from avian to human hosts. 100% prevalence of L26I/V27A mutation increased the mortality rates from 51% (95% confidence interval [CI] 37%-65%) to 89% (95% CI 88%-90%). Mutations involving Leu26 or Val27 were identified to be the major mutations emerging from drug selection pressure. Thus the emergence of the super H5N1 virus with a fatality of over 90% may be attributed to the abuse of amantadine in poultry, especially in some southeast Asian countries. A more stringent control to antiviral veterinary drugs is imperative.
    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
    从惰性N2分子的吸附开始,在温和条件下进行尿素电合成已经在实验上提出了一种有希望的替代方案,以克服工业Haber-Bosch工艺中的巨大能耗。最关键和不可避免的反应是基于预先选择的反应途径,由*N2和CO形成尿素前体*NCON,以及以下质子化过程。从大量反应数据中理解它们的内在相互关系并探索其主要描述符具有重要意义。特此,作者研究了锚定在N掺杂石墨烯上的分散双金属(同核MN3-MN3部分和异核MN3-M\'N3部分)作为电催化剂合成尿素。以从头算分子动力学(AIMD)模拟筛选出的72个稳定系统为数据库,在计算的吉布斯自由能和其他重要因素之间实现了六个显著的线性相关性。最令人鼓舞的是,建立了主要描述符(ΔE(*NCONH)),因为可以滤除72%的低性能系统,并且其有效范围(-1.0eV<ΔEE(*NCONH)<0.5eV)由八个最佳系统确定。这项研究不仅表明,通过MN3部分分散的双金属可以作为尿素生产的有希望的活性位点。而且还确定了高通量方法中的主要描述符及其有效范围。
    Urea electrosynthesis under mild conditions starting from the adsorption of inert N2 molecules has brought out a promising alternative experimentally to conquer its huge energy consumption in industrial Haber-Bosch process. The most crucial and inevitable reaction is the formation of urea precursor *NCON from *N2 and CO based on the pre-selected reaction pathway, together with the following protonated processes. It is significant to comprehend their intrinsic intercorrelation and explore the principal descriptor from massive reaction data. Hereby, the authors study the dispersed dual-metals (homonuclear MN3 -MN3 moiety and heteronuclear MN3 -M\'N3 moiety) anchored on N-doped graphene as electrocatalysts to synthesize urea. Based on the screened out 72 stable systems by ab initio molecular dynamics (AIMD) simulations as the database, six significant linear correlations between the computed Gibbs free energy and other important factors are achieved. Most encouragingly, the principal descriptor (ΔE(*NCONH)) is established because 72% low-performance systems can be filtered out and its effective range (-1.0 eV < ΔEE(*NCONH) < 0.5 eV) is identified by eight optimal systems. This study not only suggests that dispersed dual-metals via MN3 moiety can serve as promising active sites for urea production, but also identifies the principal descriptor and its effective range in high-throughput methods.
    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