inflection point

  • 文章类型: Journal Article
    在这里,我们研究了涂覆有钯(AuNRs@Pd)的单金纳米棒所表现出的独特散射特性,随着Pd壳厚度和形态的变化。通过使用两种不同浓度的Pd前体的自下而上外延Pd生长来合成AuNRs@Pd。这些单个AuNRs@Pd显示了亚辐射和超辐射局域表面等离子体共振峰的特征,特征是一个明显的间隙,标志着一个Fano的下降。我们揭示了局部折射率(RI)对亚辐射和超辐射峰值能量的影响,以及具有不同Pd壳厚度的AuNRs@Pd的散射光谱中的Fano倾角。我们证明了拐点(IF)方法在检测不同RI的峰和倾角变化方面的适用性。与厚AuNRs@Pd2mM相比,薄AuNRs@Pd1mM对局部RI变化的峰值位移表现出更明显的敏感性。相比之下,厚AuNR@Pd2mM对亚辐射和超辐射峰能量附近的曲率变化表现出更高的敏感性,而不是不同局部RI的峰位移敏感性。此外,在不同的局部RI中,与薄AuNRs@Pd1mM相比,厚AuNRs@Pd2mM中的Fano倾角变化更为明显。因此,我们提供了对亚辐射RI敏感性的新见解,超辐射,单AuNRs@Pd中的Fano共振模式。
    Herein, we investigated the distinctive scattering properties exhibited by single gold nanorods coated with palladium (AuNRs@Pd), with variations in the Pd shell thicknesses and morphologies. AuNRs@Pd were synthesized through bottom-up epitaxial Pd growth using two different concentrations of Pd precursor. These single AuNRs@Pd displayed the characteristic of subradiant and superradiant localized surface plasmon resonance peaks, characterized by a noticeable gap marked by a Fano dip. We revealed the effect of local refractive index (RI) on the subradiant and superradiant peak energies, as well as the Fano dip in the scattering spectra of AuNRs@Pd with different Pd shell thicknesses. We demonstrated the applicability of the inflection points (IFs) method on detecting peaks and dip changes across different RIs. Thin AuNRs@Pd1mM displayed more pronounced sensitivity to peak shifts in response to variations in local RIs compared to thick AuNRs@Pd2mM. In contrast, thick AuNRs@Pd2mM exhibited greater sensitivity to changes in curvature near the subradiant and superradiant peak energies rather than peak shift sensitivity across different local RIs. Moreover, the Fano dip shift was more noticeable in thick AuNRs@Pd2mM compared to thin AuNRs@Pd1mM across different local RIs. Therefore, we provided new insight into the RI sensitivity on subradiant, superradiant, and Fano resonance modes in single AuNRs@Pd.
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  • 文章类型: Journal Article
    数学模型可以帮助研究人员描述生物过程,像增长一样,在动物中。本研究旨在收集18只波尔山羊的体重数据和20只波尔山羊的体重数据,从出生到成熟,对增长进行建模并确定增长趋势。这是一项新颖的调查,作为从出生到成熟这两种波尔山羊性别的年龄-体重数据库的足够信息,缺乏。使用年龄-体重数据,四种非线性模型,也就是Brody,Gompertz,Logistic和VonBertalanffy增长模型,被绘制和评估。比较每个生长模型的模型参数在两种性别之间的差异。使用AIC和RMSE确定每个模型的拟合统计有效性,R2也在考虑之中。除了Brody模型之外的所有模型,预测阉割的成熟重量明显更重。Brody模型被认为不适合描述Boer山羊的生长,因为该函数严重高估了两性从出生到成熟的体重。VonBertalanffy(R2=91.3)和Gompertz函数(R2=91.3)显示出最适合布尔山羊去势,而Gompertz模型(R2=95.1)显示出与波尔山羊的最佳拟合。Gompertz函数是描述波尔山羊总体生长的首选模型,因为它准确地描述了两性的生长。根据Gompertz模型,达到生长曲线拐点的年龄,去势和去势之间没有显着差异(141.80天对136.31天)。两种性别之间的成熟率也没有显着差异。
    Mathematical models may aid researchers in describing biological processes, like growth, in animals. This study aimed to collect the body weight data of 18 Boer goat castrates and 20 Boer goat does, from birth until maturity, to model growth and determine growth trends. This is a novel investigation as sufficient information on an age-weight database for these two Boer goat sexes from birth to maturity, is lacking. Using age-weight data, four nonlinear models, namely the Brody, Gompertz, Logistic and Von Bertalanffy growth models, were plotted and evaluated. The model parameters of each growth model were compared for differences between the two sexes. The statistical effectiveness of fit was determined for each model using AIC and RMSE, with R2 also being considered. All models except the Brody model, predicted significantly heavier mature weights for castrates. The Brody model was deemed unfit to describe Boer goat growth as the function severely over-predict weights from birth until maturity for both sexes. The Von Bertalanffy (R2 = 91.3) and Gompertz functions (R2 = 91.3) showed the best fit for Boer goat castrates, while the Gompertz model (R2 = 95.1) showed the best fit for Boer goat does. The Gompertz function is the preferred model to depict Boer goat growth overall, as it accurately characterized growth of both sexes. According to the Gompertz model the age at which the inflection point of the growth curve was reached, did not differ significantly between castrates and does (141.80 days versus 136.31 days). There was also no significant difference in maturation rate between the two sexes.
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  • 文章类型: Journal Article
    Vitamin D deficiency is a global public health concern that provokes bone demineralization and weakening. In response to the decreased vitamin D level, calcium stores wear out. The homeostatic effect of compensatory hyperparathyroidism in vitamin D deficiency incites variable discrepancies in different populations. This study intends to decipher the transition point of PTH in relation to levels of vitamin D in a Nepalese population. A cross-sectional study was carried out at Tribhuvan University Teaching Hospital, Nepal. Serum calcium, phosphorus, intact PTH, and 25-hydroxy vitamin D levels were assayed in an Abbott ARCHITECT Integrated System. A correlation plot of PTH and vitamin D was analyzed in Statistical Package for Social Sciences version 22.0. Using a locally weighted scatter plot smoothing method, the relation between these variables was presented graphically. Among 281 individuals, 30.2% had vitamin D levels below 20 ng/mL. There was an archetypical transition in the PTH levels in concert with the decrease in vitamin D level marked by 2 inflection points (ie, 18.5 and 42.0 ng/mL). Our findings suggest that to augment overall health and avert weakness due to vitamin D deficiency, the levels of vitamin D should be maintained above 42.0 ng/mL in our population.
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  • 文章类型: Journal Article
    本文旨在介绍内部开发的Java程序的显着特征,该程序用于确定平坦化无滤波器(FFF)光子束的拐点和剂量测定参数。还给出了FFF光子束的剂量测定参数的参考水平。
    使用内部开发的Java程序和手动方法分析了在从各种机构获得的等中心设置中在10cm深度处测量的20cm×20cm的准直器设置的6MVFFF和10MVFFF光子束的光束轮廓。参考剂量值(RDV),字段大小,半影,和不平坦度(定义为90%[X90%]之间的横向间隔,75%[X75%],和曲线上的60%[X60%]剂量点)进行计算和比较。字段大小的参考值,半影,还确定了Varian和Elekta医用电子直线加速器(LINAC)的非平坦度。
    对于6和10MVFFF光子束,使用Java方法和手动方法确定的RDV的最大差异分别为2.4%和2.7%,分别。字段大小值之间的最大差异,半影,使用Java和手动方法确定的不平坦度在1.3mm以内。瓦里安LINAC的视野大小和半影的参考值分别为19.94±0.10cm和0.83±0.08cm(6MVFFF)和19.95±0.10cm和0.83±0.08cm(10MVFFF)。同样,ElektaLINAC的视野大小和半影参考值分别为20.02±0.09cm和0.94±0.12cm(6MVFFF)和20.03±0.11cm和0.97±0.16cm(10MVFFF)。
    在Java中开发了一种软件程序,用于分析FFF光子束的束轮廓。发现Java导出的FFF光子束剂量测定参数值的结果与使用手动方法确定的值非常吻合。这些参数的参考值也是使用大量数据得出和引用的。
    UNASSIGNED: This article aimed to present the salient features of the in-house developed Java program for the determination of inflection point and dosimetric parameters of flattening filter-free (FFF) photon beam. Reference levels for the dosimetric parameters of the FFF photon beams were also presented.
    UNASSIGNED: Beam profiles of 6 MV FFF and 10 MV FFF photon beams for a collimator setting of 20 cm × 20 cm measured at 10 cm depth in an isocentric setup acquired from various institutions were analyzed using an in-house developed Java program and manual method. The values of reference dose value (RDV), field size, penumbra, and degree of un-flatness (defined as the lateral separation between 90% [X90%], 75% [X75%], and 60% [X60%] dose points on the profile) were calculated and compared. The reference values of field size, penumbra, and degree of un-flatness were also determined for Varian and Elekta medical electron linear accelerators (LINACs).
    UNASSIGNED: The maximum differences for RDV determined using the Java method and manual method are 2.4% and 2.7% for 6 and 10 MV FFF photon beams, respectively. The maximum difference between the values of field size, penumbra, and degree of un-flatness determined using Java and manual methods is within 1.3 mm. The reference values of field size and penumbra for Varian LINACs are 19.94 ± 0.10 cm and 0.83 ± 0.08 cm (6 MV FFF) and 19.95 ± 0.10 cm and 0.83 ± 0.08 cm (10 MV FFF). Similarly, the reference values of field size and penumbra for Elekta LINACs are 20.02 ± 0.09 cm and 0.94 ± 0.12 cm (6 MV FFF) and 20.03 ± 0.11 cm and 0.97 ± 0.16 cm (10 MV FFF).
    UNASSIGNED: A software program was developed in Java for analyzing the beam profiles of FFF photon beams. The results of Java-derived values of dosimetric parameters of FFF photon beams were found in good agreement with the values determined using the manual method. The reference values of these parameters were also derived and quoted using a large cohort of the data.
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  • 文章类型: Journal Article
    工业过程中的废水处理和纯化水的再利用可以提供新鲜水的替代来源,并通过排放较少量的废水来减少污染负荷。当吸附用于处理时,使用过的吸附剂的再生也可能占操作成本的很大一部分并引起二次污染。这个问题可以通过使用柱方法循环重复吸附/再生循环来解决。在本文中,研究了使用柱法进行的锌捕获和沸石床再生的总共九个连续循环。穿透曲线的导出形式用于分析柱中的传质。为此,剂量反应,托马斯,Bohart-Adams,Yoon-Nelson和Wolborska模型用于通过非线性回归分析对穿透曲线进行建模。讨论了仿真结果和模型之间的数学相似性。这是第一项使用衍生形式的剂量响应模型来分析锌离子在天然沸石上的九个连续吸附-再生循环期间的穿透曲线和传质的拐点的研究。对所有循环分析获得的峰形速率曲线。关于拐点评估了最佳操作条件,模型参数,和停留时间。
    Treatment of wastewater and reuse of purified water in an industrial process can provide an alternative source of fresh water as well as reduce pollution load by discharging a lower quantity of wastewater. When adsorption is used for treatment, the regeneration of the used adsorbent may also account for a large portion of the operational cost and cause secondary pollution. This problem may be solved by cyclic repetition of adsorption/regeneration cycles using a column method. In this paper, a total of nine successive cycles of zinc capture and zeolite bed regeneration using a column method have been investigated. The derived form of the breakthrough curve was used for analysing mass transfer in the column. For that purpose, the Dose-response, the Thomas, the Bohart-Adams, the Yoon-Nelson and the Wolborska models were used for modelling the breakthrough curve by nonlinear regression analysis. Simulation results and mathematical similarities between the models were discussed. This is the first study that used derived form of Dose-response model to analyse the inflection points of the breakthrough curve and mass transfer during nine consecutive sorption-regeneration cycles of zinc ions on natural zeolite. Obtained peak shape rate profiles were analysed for all cycles. Optimal operation conditions were evaluated with respect to the inflection point, the model parameters, and the residence time.
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  • 文章类型: Journal Article
    目的:本研究的目的是探讨胸椎后凸(TK)和腰椎前凸(LL)参数之间的相关性,并建立相应的线性回归来预测TK形态和由无症状成年人的个体LL参数确定的胸腰椎拐点(IP)。
    方法:共招募280名成年健康志愿者,并以站立姿势对每位受试者进行全脊柱X射线检查。测量了以下矢状参数:累积TK,LL,近端LL(PLL),TK(TKA)和LL(LLA)的顶点,IP以及从胸尖(TAPL)和腰尖(LAPL)的铅垂线到重力线的距离。分析了TK和LL参数之间的相关性,并进行相应的线性回归。
    结果:TK对齐存在广泛的差异,包括角度和形态参数。此外,所有累积TK角度与LL(r值从-0.173到-0.708)和PLL(r值从-0.206到-0.803)有统计相关性,TKA和IP与LLA(分别为rs=0.359和0.582)和TAPL与LAPL(rs=0.335)。ASD手术中使用的常见预测公式可能包括T10-L1=-3.6-0.2*LL(R2=0.201),T4-L1=3.4-0.5*LL(R2=0.457),TKA=-10.3+1.1*LLA(R2=0.180)和IP=-12.7+1.6*LLA(R2=0.330)。
    结论:无症状成人的TK和LL参数之间存在密切的关联。此外,胸部对准的预测模型,特别是累积的传统知识,基于LL参数提出,可以更好地描绘解剖关系,在成人脊柱畸形手术中引导胸廓结构,并可能有助于防止近端交界失败。
    OBJECTIVE: The aims of this study were to explore the correlations between thoracic kyphosis (TK) and lumbar lordosis (LL) parameters and to build corresponding linear regressions to predict TK morphology and the thoracolumbar inflection point (IP) determined by individual LL parameters in asymptomatic adults.
    METHODS: A total of 280 adult healthy volunteers were recruited, and full-spine X-rays were performed for each subject in a standing posture. The following sagittal parameters were measured: cumulative TK, LL, proximal LL (PLL), the apices of TK (TKA) and LL (LLA), the IP and the distance from the plumb line of the thoracic apex (TAPL) and the lumbar apex (LAPL) to the gravity line. The correlations between TK and LL parameters were analyzed, and the corresponding linear regressions were conducted.
    RESULTS: Extensive variations existed in TK alignment, including angular and morphological parameters. In addition, there were statistical correlations of all cumulative TK angles with LL (r values from - 0.173 to - 0.708) and PLL (r values from - 0.206 to - 0.803), TKA and IP with LLA (rs = 0.359 and 0.582, respectively) and TAPL with LAPL (rs = 0.335). The common predictive formulas employed in ASD surgery could include T10-L1 = - 3.6-0.2*LL (R2 = 0.201), T4-L1 = 3.4-0.5*LL (R2 = 0.457), TKA = - 10.3 + 1.1*LLA (R2 = 0.180) and IP = - 12.7 + 1.6*LLA (R2 = 0.330).
    CONCLUSIONS: There were intimate associations between TK and LL parameters in asymptomatic adults. Moreover, predictive models for thoracic alignment, particularly cumulative TK, based on LL parameters were proposed, which could better delineate anatomical relationships, guide thoracic construction during adult spinal deformity surgery and may help preventing proximal junctional failure.
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  • 文章类型: Journal Article
    方法:前瞻性队列研究。
    目的:显示拐点(IP)的人口差异及其在定义最大胸椎后凸(TK)和腰椎前凸(LL)中的作用。
    方法:468名无症状的成年志愿者被纳入多种族规范研究(MEANS)。要查找与IP相关的参数,对椎骨和椎间盘进行编号,使C7为0,T1为1,T1-T2椎间盘为1.5等。通过IP和9个其他选定参数的相关矩阵以及线性回归进行统计分析。
    结果:总平均IP为12.44,大致相当于T12-L1盘,中位数为12.50,范围为T8-L4。然后按性别和种族对队列进行分层,但两组间IP无显著差异。年轻受试者的IP为13(L1),与年龄较大的受试者的12.5(T12-L1盘)相比(P<0.05)。IP与TK顶点中度相关(r=0.66)。在IP和LL幅度或顶点之间没有发现强相关性,TK量级,骶骨斜坡,或骨盆入射(PI)。就其他矢状参数而言,PI与LL呈显著正相关。PI和TK没有很强的关联。
    结论:平均IP位于T12-L1椎间盘,然而IP范围从T8到L4。年龄较大的受试者倾向于具有相对较高的头颅IP。没有发现放射学变量是IP的强预测因子。发现TK顶点具有中等相关性。
    METHODS: Prospective cohort study.
    OBJECTIVE: To show population variance in the Inflection Point (IP) and its role in defining maximum Thoracic Kyphosis (TK) and Lumbar Lordosis (LL).
    METHODS: 468 asymptomatic adult volunteers were included in the Multi-Ethnic Normative Alignment Study (MEANS). To find parameters correlating with IP, the vertebrae and discs were numbered such that C7 was 0, T1 was 1, with T1-T2 disc being 1.5, etc. Statistical analysis was performed by a correlation matrix for IP and the 9 other selected parameters along with linear regressions.
    RESULTS: The overall mean IP was 12.44 approximately corresponding to T12-L1 disc with the median being 12.50, range was T8-L4. The cohort was then stratified by sex and ethnicity, but there was no significant difference in IP between groups. IP in younger subjects was 13 (L1), compared to 12.5 (T12-L1 disc) in older subjects (P < .05). IP was moderately correlated with the TK apex (r = .66). No strong correlation was found between IP and LL magnitude or apex, TK magnitude, sacral slope, or Pelvic Incidence (PI). In terms of other sagittal parameters, PI and LL demonstrated a significant positive correlation. PI and TK did not have a strong association.
    CONCLUSIONS: The mean IP was at the T12-L1 disc, however IP ranged from T8 to L4. Older subjects tended to have a relatively more cephalad IP. No radiographic variable was found to be a strong predictor of the IP. TK apex was found to have a moderate correlation.
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  • 文章类型: Journal Article
    背景:许多因素导致全肩关节置换术(TSA)后手术部位感染(SSI)的风险。手术时间是一个可改变的因素,可能会导致TSA后发生SSI。本研究旨在确定TSA后手术时间与SSI之间的相关性。
    方法:使用美国外科医生学会国家外科质量改进计划(ACS-NSQIP)数据库,从2006年至2020年,共查询了33,987份患者记录,并按手术时间和术后30天的SSI发展情况进行分类.根据手术时间计算发生SSI的几率。
    结果:在本研究的33,470名患者中,169名患者在术后30天发生SSI,导致整体SSI率为0.50%。手术时间与SSI发生率呈正相关。在手术时间180分钟时确定了一个拐点,手术时间超过180分钟,SSI发生率显着增加。
    结论:手术时间增加与术后30天内SSI风险增加密切相关。在180分钟有一个显著的拐点。
    结论:TSA的目标手术时间应小于180分钟,以降低SSI的风险。
    BACKGROUND: Many factors contribute to the risk of surgical-site infection (SSI) following total shoulder arthroplasty (TSA). Operative time is a modifiable factor that may contribute to SSI occurrence after TSA. This study aimed to determine the correlation between operative time and SSI following TSA.
    METHODS: By use of the American College of Surgeons National Surgical Quality Improvement Program database, a total of 33,987 patient records were queried from 2006 to 2020 and sorted by operative time and the development of an SSI in the 30-day postoperative period. Odds ratios for the development of an SSI were calculated based on operative time.
    RESULTS: An SSI developed in the 30-day postoperative period in 169 of the 33,470 patients in this study, resulting in an overall SSI rate of 0.50%. A positive correlation was identified between operative time and the SSI rate. An inflection point was identified at an operative time of 180 minutes, with a significant increase in the rate of SSI occurrence for operative times >180 minutes.
    CONCLUSIONS: Increased operative time was shown to be strongly correlated with an increased risk of SSI within 30 days following surgery, with a significant inflection point at 180 minutes. The target operative time for TSA should be <180 minutes to reduce the risk of SSI.
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  • 文章类型: Journal Article
    先前的研究表明,血清白蛋白与前列腺癌(PCa)有关,但在没有PCa病史的人群中,前列腺特异性抗原(PSA)水平没有。因此,我们分析了国家健康和营养调查(NHANES)(2003-2010)提供的次要数据.
    总共,从NHANES数据库(2003-2010)中选择了5,469名参与者。血清白蛋白和PSA水平被连续认为是独立和因变量,连续。本研究中包括了一些协变量,包括人口统计,饮食,体检,和合并症数据。采用加权线性回归模型和平滑曲线拟合,研究了血清白蛋白与PSA之间的线性和非线性关系。
    在调整了潜在的干扰因素后,加权多元线性回归分析显示,血清白蛋白不能独立预测PSA水平(β=-0.00995CI:-0.020,0.002).然而,血清白蛋白和PSA之间存在非线性关系,点41克/升拐点的左边,效果大小,95CI和P值分别为0.019(log2转化)(-0.006,0.043)和0.1335。我们在拐点右侧发现血清白蛋白和PSA呈负相关,效果大小,95CI,P值为-0.022(log2变换)(-0.037,-0.007),0.0036.
    总之,血清白蛋白和PSA水平不呈线性关系。当血清白蛋白水平超过41克,血清白蛋白水平与PSA水平呈负相关。
    Previous studies have shown that serum albumin is associated with prostate cancer (PCa), but not with prostate-specific antigen (PSA) levels in populations without PCa history. Therefore, we analyzed secondary data provided by the National Health and Nutrition Examination Survey (NHANES) (2003-2010).
    In total, 5,469 participants were selected from the NHANES database (2003-2010). Serum albumin and PSA levels were serially considered independent and dependent variables, serially. A number of covariates were included in this study, including demographic, dietary, physical examination, and comorbidity data. Using weighted linear regression model and smooth curve fitting, the linear and non-linear relationship between serum albumin and PSA was investigated.
    After modulating underlying interference factors, the weighted multivariate linear regression analysis revealed that serum albumin did not independently predict PSA levels (β = -0.009 95%CI: -0.020, 0.002). Nevertheless, a non-linear relationship was found between serum albumin and PSA, with a point of 41 g/L. Left of the inflection point, the effect size, 95%CI, and P-value were 0.019 (log2 transformation) (-0.006, 0.043) and 0.1335, respectively. We found a negative association between serum albumin and PSA on the right side of the inflection point, with effect size, 95%CI, and a P-value of -0.022 (log2 transformation) (-0.037, -0.007), 0.0036.
    In summary, serum albumin and PSA levels are not linearly related. When serum albumin levels exceed 41 g, serum albumin levels are negatively associated with PSA levels.
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  • 文章类型: Journal Article
    背景了解高血压(BP)的自然史对于确定高血压一级预防的窗口很重要。作者旨在调查血压升高的自然史,并检查中国成年人高血压发作前的血压轨迹是否存在拐点。方法和结果从CHNS(中国健康与营养调查)中纳入了8688名参与者,平均5个BP测量值。在每一波中,在同一只手臂上进行了三次重复测量,分析采用平均收缩压(SBP)和舒张压(DBP)。高血压发作定义为SBP≥140mmHg或DBP≥90mmHg或由医生诊断或目前正在接受抗高血压治疗。中位随访时间为13.0年。总的来说,在高血压发作之前,随着年龄的增长,BP升高显示出非线性轨迹。拐点后SBP和DBP的增长率明显快于之前。根据30至39岁、40至49岁、50至59岁、60至69岁和70至79岁的高血压发病情况,在拐点,患者分别为≈29、38、48、57和67岁,SBP水平为112.6、114.8、116.8、117.4和118.0mmHg,DBP水平分别为73.4、75.7、76.9、76.2和73.8mmHg,分别。结论高血压发病前存在BP升高的非线性轨迹。SBP和DBP的拐点在112至118mmHg和73至77mmHg的范围内,分别。一旦血压水平超过变化点,SBP和DBP升高较快。
    Background Understanding the natural history of elevated blood pressure (BP) is important to determine the window for primary prevention of hypertension. The authors aimed to investigate the natural history of elevated BP and examine whether there were inflection points in BP trajectories preceding hypertension onset in Chinese adults. Methods and Results A total of 8688 participants with an average of 5 BP measurements were included from the CHNS (China Health and Nutrition Survey). In each wave, triplicate measurements on the same arm were taken, and the mean systolic BP (SBP) and diastolic BP (DBP) were used in the analysis. Hypertension onset was defined as SBP ≥140 mm Hg or DBP ≥90 mm Hg or diagnosed by physician or currently under antihypertensive treatment. The median follow-up time was 13.0 years. Overall, BP elevation with age prior to the onset of hypertension showed a nonlinear trajectory. The increased rates in both SBP and DBP were obviously faster after the inflection point than before. According to hypertension onset at age 30 to 39, 40 to 49, 50 to 59, 60 to 69, and 70 to 79 years, at the inflection point, patients were ≈29, 38, 48, 57, and 67 years, SBP levels were 112.6, 114.8, 116.8, 117.4, and 118.0 mm Hg, and DBP levels were 73.4, 75.7, 76.9, 76.2, and 73.8 mm Hg, respectively. Conclusions There was a nonlinear trajectory of BP elevation preceding hypertension onset. The inflection points for SBP and DBP were in the range of 112 to 118 mm Hg and 73 to 77 mm Hg, respectively. Once BP levels exceeded the changing points, the level of SBP and DBP increased more rapidly.
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