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.
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  • 文章类型: Journal Article
    在患有1型糖尿病(T1D)的成年人中,时间范围(TIR)[70-180mg/dl]已被提议作为除HbA1c之外的额外度量。这项回顾性单中心队列研究确定了2、4和12周内HbA1c与TIR之间的相关性(TIR2w,TIR4w和TIR12w)在儿科T1D人群中进行咨询之前。共纳入168名T1D儿童。连续血糖监测数据,收集HbA1c和人口统计学变量。我们发现HbA1c和TIR2w之间有很强的线性相关性(R=-0.571),TIR4w(R=-0.603)和TIR12w(R=-0.624)。TIR2w和TIR12w之间存在很强的相关性,HbA1c和高于范围的时间(TAR)以及不同时间点的TIR和TAR。总之,HbA1c和TIR之间有很强的相关性,使TIR成为HbA1c的潜在补充指标。TIR2w似乎是TIR12w的可行替代品。TAR在评估血糖控制方面似乎也很有希望。
    In adults with type 1 diabetes (T1D), time in range (TIR) [70-180 mg/dL] has been proposed as an additional metric besides glycated hemoglobin (HbA1c). This retrospective monocentric cohort study determined the correlation between HbA1c and TIR during the 2, 4, and 12 weeks (TIR2w, TIR4w, and TIR12w) before consultation in a pediatric T1D population. A total of 168 children with T1D were included. Continuous glucose monitoring data, HbA1c, and demographic variables were collected. We found strong linear correlations between HbA1c and TIR2w (R = -0.571), HbA1c and TIR4w (R = -0.603), and between HbA1c and TIR12w (R = -0.624). A strong correlation exists between TIR2w and TIR12w, HbA1c and time above range (TAR), and between TIR and TAR at different time points. In conclusion, a strong correlation was found between HbA1c and TIR, making TIR a potentially complementary metric to HbA1c. TIR2w seems a viable alternative to TIR12w. TAR also seems promising in assessing glycemic control.
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  • 文章类型: Journal Article
    高效且经济实惠的电池需要设计新型有机电极材料,以克服传统使用的无机材料的缺点,和潜在候选人的计算筛选是一个非常有效的方法来确定预期的解决方案,并尽量减少实验测试。在这里,我们提出了DFT高通量计算筛选,其中PUBCHEM数据库中包含的8600万个分子已根据其估计的电化学特征进行了分析和分类。确定了5445名表现最好的候选人,其中,预期2306相对于(Li/Li+)具有高于4V的单电子还原电势。类似地,预测626个分子的单电子能量密度高于800Whkg-1。对某些材料进行的显式计算表明,至少有69个候选物具有高于1300Whkg-1的双电子能量密度。成功的分子被分成几个家族,其中一些已经常用的电极材料,和其他人仍未经实验测试。它们中的大多数是含有共轭CO的小系统,NN,或NC官能团。我们选择的分子为实验家探索有机电极的新材料提供了有价值的起点。
    Efficient and affordable batteries require the design of novel organic electrode materials to overcome the drawbacks of the traditionally used inorganic materials, and the computational screening of potential candidates is a very efficient way to identify prospective solutions and minimize experimental testing. Here we present a DFT high-throughput computational screening where 86 million molecules contained in the PUBCHEM database have been analyzed and classified according to their estimated electrochemical features. The 5445 top-performing candidates were identified, and among them, 2306 are expected to have a one-electron reduction potential higher than 4 V versus (Li/Li+ ). Analogously, one-electron energy densities higher than 800 Whkg-1 have been predicted for 626 molecules. Explicit calculations performed for certain materials show that at least 69 candidates with a two-electron energy density higher than 1300 Whkg-1 . Successful molecules were sorted into several families, some of them already commonly used electrode materials, and others still experimentally untested. Most of them are small systems containing conjugated CO, NN, or NC functional groups. Our selected molecules form a valuable starting point for experimentalists exploring new materials for organic electrodes.
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  • 文章类型: Journal Article
    开发了一种快速HPLC方法来研究药学相关分子片段的疏水性程度。通过这一战略,在早期药物发现计划中,可用于物理化学评估的样品数量减少并不是限制因素。先前合成了所研究的16种酸片段,还通过电位法确定了其实验logD值。对于四个片段,不可能确定这样的性质,因为它们的值在仪器工作范围之外(2 A fast HPLC method was developed to study the hydrophobicity extent of pharmaceutically relevant molecular fragments. By this strategy, the reduced amount of sample available for physico-chemical evaluations in early-phase drug discovery programs does not represent a limiting factor. The sixteen acid fragments investigated were previously synthesized also determining potentiometrically their experimental log D values. For four fragments it was not possible to determine such property since their values were outside of the instrumental working range (2 < pKa  < 12). An RP-HPLC method was therefore optimized. For each scrutinized method, some derived chromatographic indices were calculated, and Pearson\'s correlation coefficient (r) allowed to select the so-called \"φ0 index\" as the best correlating with the log D. The w s p H ${}_w^spH$ was fixed at 3.5 and a modification of some variables [organic modifier (methanol vs. ACN), stationary phase (octyl vs. octadecyl), presence/absence of the additives n-octanol, n-butylamine, and n-octylamine], allowed to select the best correlation conditions, producing a r = 0.94 (p < 0.001). Importantly, the φ0 index enabled the estimation of log D values for four fragments which were unattainable by potentiometric titration. Moreover, a series of molecular descriptors were calculated to identify the chemical characteristics of the fragments explaining the obtained φ0 . The number of hydrogen bond donors and the index of cohesive interaction correlated with the experimental data.
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  • 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.
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  • 文章类型: Journal Article
    当受试者在隐蔽的地点对目标做出反应时,哪些神经元信号可以预测反应时间?尽管最近的研究表明峰值率不能预测,这仍然是一个非常有争议的问题。因此,当猕猴执行隐蔽的空间注意力任务时,我们记录了额叶眼场(FEF)神经元的单单位活动。我们发现,FEF神经元峰值速率的注意力调节与行为反应时间密切相关。此外,这种相关性已经在目标调光前1秒出现,触发行为反应。在神经元中发现了这种通过尖峰速率预测反应时间的方法,这些神经元显示出目标和干扰物的注意力依赖性增强和抑制的活动,分别,然而在不同程度上跨科目。因此,FEF神经元的峰值速率可以在选择性注意力任务期间的操作行为之前持续地预测反应时间。如此长的预测窗口将有助于开发基于尖峰的脑机接口。
    Which neuronal signal(s) predict reaction times when subjects respond to a target at covertly attended locations? Although recent studies showed that spike rates are not predictive, it remains a highly contested question. Therefore, we record single-unit activity from frontal eye field (FEF) neurons while macaques are performing a covert spatial attention task. We find that the attentional modulation of spike rates of FEF neurons is strongly correlated with behavioral reaction times. Moreover, this correlation already emerges 1 s before target dimming, which triggers the behavioral responses. This prediction of reaction times by spike rates is found in neurons showing attention-dependent enhanced and suppressed activity for targets and distractors, respectively, yet in varying degrees across subjects. Thus, spike rates of FEF neurons can predict reaction times persistently and well before the operant behavior during selective attention tasks. Such long prediction windows will be useful for developing spike-based brain-machine interfaces.
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  • 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.
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  • 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.
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  • 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.
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  • 文章类型: Journal Article
    无麸质产品被列入今天的议程,因为它们代表了市场上最匆忙增长的细分市场,代表食品公司的机会。然而,众所周知,面筋是小麦面团系统中至关重要的网络结构,这说明了最终烘焙产品的总体预期技术特征。因此,面筋的缺乏会对无面筋面包的特性产生负面影响,在制造具有类似小麦衍生产品特征的产品时引发了技术挑战。已经研究了寻找新的蛋白质来源作为规避麸质去除的技术缺陷的方法。乳制品蛋白是功能性分子,可能能够建立蛋白质网络结构,从而改善无麸质产品的技术特性。在目前的工作中,不同水平的乳制品添加(10%和20%,w/w)用于补充无麸质面包配方,对面团流变学特性的影响与获得的面包工艺质量参数密切相关。获得了面团流变学的稳定剪切(粘度)和振荡(弹性和粘性模量)值与面包质量参数(体积和硬度)之间的线性相关性(R2>0.904)。这表明面包质量的提高与乳制品的添加水平成正比。同样,粘贴特性参数与面包陈腐率之间的强线性相关性(R2>-0.910)支持了以下假设:测试的乳制品具有产生低陈腐率面包的高潜力,这是延长保质期的优点。总之,结果证实,两种乳制品的添加,作为面包店的配料,可以构成提高整体无麸质面包质量的技术优势。
    Gluten-free products are on today\'s agenda since they represent the most hastily growing segments in the market, representing an opportunity for food companies. Nevertheless, it is well-known that gluten is a crucial network structure in the wheat dough systems, which accounts for the overall desired technological features of the final bakery goods. Therefore, the absence of gluten negatively affects the characteristics of gluten-free bread, triggering a technological challenge in the manufacturing of products with resembled characteristics of wheat-derived counterparts. The search for new protein sources has been studied as an approach to circumvent the technological drawbacks of gluten removal. Dairy proteins are functional molecules that can likely be capable of building up a protein-network structure so that it would improve the technological properties of gluten-free products. In the present work, different levels of dairy product addition (10 and 20%, w/w) were used to supplement the gluten-free bread formulas, and the impact on dough rheology properties was well correlated to the bread technological quality parameters obtained. Linear correlations (R 2 > 0.904) between steady shear (viscosity) and oscillatory (elastic and viscous moduli) values of the dough rheology with bread quality parameters (volume and firmness) were obtained, suggesting that the bread quality improvements are proportional to the levels of dairies added. Likewise, strong linear correlations (R 2 > -0.910) between pasting properties parameters and bread staling rate supported the hypothesis that the dairies tested have a high potential to generate bread with a low staling rate, which is an advantage to extending the shelf-life. In short, results confirmed that the addition of both dairy products, as bakery ingredients, can constitute a technological advantage to improve the overall gluten-free bread quality.
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