Quantitative methods

定量方法
  • 文章类型: Journal Article
    人类肠道微生物群是指共生存在于人类肠道系统中的多种微生物群落。改变的微生物群落与许多人类病理有关。然而,在实践中缺乏快速有效的方法来评估肠道微生物群特征.为了解决这个问题,我们建立了一个包含45个定量实时聚合酶链反应(qPCR)检测方法的评估系统,这些方法针对人群中患病率和/或丰度较高的肠道核心微生物。通过比较基因组分析,我们为45种核心微生物中的31种选择了新的物种特异性遗传标记和引物,这些核心微生物没有先前报道的特异性引物或其引物的特异性需要改进.我们全面评估了qPCR检测的性能,并证明它们显示出良好的灵敏度,选择性,和每个目标的定量线性。这些靶标的基因组DNA的检测限范围为0.1至1.0pg/µL。我们还证明了qPCR方法和宏基因组学下一代测序(mNGS)方法在分析22个人类粪便样品中选定细菌的丰度方面的高度一致性(Pearson'sr=0.8688,P<0.0001)。此外,我们使用qPCR定量了14个个体中这些核心微生物的动态变化(超过8周),大多数参与者都表现出相当大的稳定性,尽管存在显著的个体差异。总的来说,这项研究能够简单快速地定量人体肠道中的45种核心微生物,提供了一个有前途的工具来了解肠道核心微生物群在人类健康和疾病中的作用。关键点:•开发了一组原始qPCR测定以量化人类肠道核心微生物。•使用真实粪便样品评价qPCR测定并与mNGS比较。•该方法用于动态地描绘个体中的肠道核心微生物群。
    The human gut microbiota refers to a diverse community of microorganisms that symbiotically exist in the human intestinal system. Altered microbial communities have been linked to many human pathologies. However, there is a lack of rapid and efficient methods to assess gut microbiota signatures in practice. To address this, we established an appraisal system containing 45 quantitative real-time polymerase chain reaction (qPCR) assays targeting gut core microbes with high prevalence and/or abundance in the population. Through comparative genomic analysis, we selected novel species-specific genetic markers and primers for 31 of the 45 core microbes with no previously reported specific primers or whose primers needed improvement in specificity. We comprehensively evaluated the performance of the qPCR assays and demonstrated that they showed good sensitivity, selectivity, and quantitative linearity for each target. The limit of detection ranged from 0.1 to 1.0 pg/µL for the genomic DNA of these targets. We also demonstrated the high consistency (Pearson\'s r = 0.8688, P < 0.0001) between the qPCR method and metagenomics next-generation sequencing (mNGS) method in analyzing the abundance of selected bacteria in 22 human fecal samples. Moreover, we quantified the dynamic changes (over 8 weeks) of these core microbes in 14 individuals using qPCR, and considerable stability was demonstrated in most participants, albeit with significant individual differences. Overall, this study enables the simple and rapid quantification of 45 core microbes in the human gut, providing a promising tool to understand the role of gut core microbiota in human health and disease. KEY POINTS: • A panel of original qPCR assays was developed to quantify human gut core microbes. • The qPCR assays were evaluated and compared with mNGS using real fecal samples. • This method was used to dynamically profile the gut core microbiota in individuals.
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  • 文章类型: Journal Article
    个体异质性和区分准确性的交叉多层次分析(I-MAIHDA)是一种研究不等式的创新方法,包括健康方面的交叉不平等,疾病,社会心理,社会经济,和其他结果。与传统的单水平回归分析相比,I-MAIHDA和相关的MAIHDA方法具有概念和方法上的优势。通过研究由许多相互联系的边缘化和压迫系统产生的不平等,通过解决传统分析中研究相互作用的许多局限性,交叉MAIHDA提供了一个有价值的社会流行病学分析工具,健康心理学,精准医学和公共卫生,环境正义,和超越。该方法允许估计交叉地层之间的平均差异(地层不等式),深入探索相互作用效应,以及阶层内部和阶层之间个体结果的总个体差异(异质性)的分解。进行和解释MAIHDA模型的具体建议分散在新兴的文献中。我们将这些知识整合为可访问的概念和应用教程,用于研究连续和二元个体结果。我们在插图中强调了I-MAIHDA,然而,本教程也有助于理解相关的方法,例如多战略MAIHDA,已被提议用于临床研究和超越。本教程将为希望进行自己的分析的读者以及有兴趣扩展对该方法的理解的读者提供支持。为了证明方法论,我们提供分步分析建议,并使用模拟数据提供说明性的健康应用.我们提供数据和语法来复制我们所有的分析。
    Intersectional multilevel analysis of individual heterogeneity and discriminatory accuracy (I-MAIHDA) is an innovative approach for investigating inequalities, including intersectional inequalities in health, disease, psychosocial, socioeconomic, and other outcomes. I-MAIHDA and related MAIHDA approaches have conceptual and methodological advantages over conventional single-level regression analysis. By enabling the study of inequalities produced by numerous interlocking systems of marginalization and oppression, and by addressing many of the limitations of studying interactions in conventional analyses, intersectional MAIHDA provides a valuable analytical tool in social epidemiology, health psychology, precision medicine and public health, environmental justice, and beyond. The approach allows for estimation of average differences between intersectional strata (stratum inequalities), in-depth exploration of interaction effects, as well as decomposition of the total individual variation (heterogeneity) in individual outcomes within and between strata. Specific advice for conducting and interpreting MAIHDA models has been scattered across a burgeoning literature. We consolidate this knowledge into an accessible conceptual and applied tutorial for studying both continuous and binary individual outcomes. We emphasize I-MAIHDA in our illustration, however this tutorial is also informative for understanding related approaches, such as multicategorical MAIHDA, which has been proposed for use in clinical research and beyond. The tutorial will support readers who wish to perform their own analyses and those interested in expanding their understanding of the approach. To demonstrate the methodology, we provide step-by-step analytical advice and present an illustrative health application using simulated data. We provide the data and syntax to replicate all our analyses.
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  • 文章类型: Journal Article
    花青素,黄酮类化合物的一个子类,以其鲜艳的颜色和促进健康的特性而闻名,在营养科学和食品工业中至关重要。这篇综述文章深入研究了食品基质中花青素检测和定量的分析方法,比较定量和局部技术。定量方法,包括高效液相色谱(HPLC)和质谱(MS),提供单个花青素的精确定量和分析,但需要样品破坏,限制其在连续质量控制中的使用。局部方法,如近红外光谱(NIR)和高光谱成像,提供快速,在不损害样品完整性的情况下进行原位分析,理想的现场食品质量评估。这篇综述强调了色谱技术的进步,特别是超高效液相色谱(UHPLC)与现代检测器,提高花色苷分析的分辨率和速度。它还强调了局部技术在食品工业中的效率和最少的样品制备的重要性。通过检查两个分析领域的优势和局限性,本文旨在阐明当前的挑战和未来的进步,为改善食品中花青素的分析提供未来研究方向的见解。
    Anthocyanins, a subclass of flavonoids known for their vibrant colors and health-promoting properties, are pivotal in the nutritional science and food industry. This review article delves into the analytical methodologies for anthocyanin detection and quantification in food matrices, comparing quantitative and topical techniques. Quantitative methods, including High-performance Liquid Chromatography (HPLC) and Mass Spectrometry (MS), offer precise quantification and profiling of individual anthocyanins but require sample destruction, limiting their use in continuous quality control. Topical approaches, such as Near-infrared Spectroscopy (NIR) and hyperspectral imaging, provide rapid, in situ analysis without compromising sample integrity, ideal for on-site food quality assessment. The review highlights the advancements in chromatographic techniques, particularly Ultra-high-performance Liquid Chromatography (UHPLC) coupled with modern detectors, enhancing resolution and speed in anthocyanin analysis. It also emphasizes the growing importance of topical techniques in the food industry for their efficiency and minimal sample preparation. By examining the strengths and limitations of both analytical realms, this article aims to shed light on current challenges and prospective advancements, providing insights into future research directions for improving anthocyanin analysis in foods.
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  • 文章类型: Journal Article
    技术接受模型(TAM)尚未应用于技术环境之外,尽管其广泛应用。这项研究将TAM扩展到消费品,并使用茶水作为消费品的代理来验证概念化的消费品接受模型(CGAM)。采用基于配额样本的探索性研究方法对CGAM进行调整和测试,表明调整后的CGAM及其措施是可靠和有效的,因此支持将TAM扩展到非技术环境是可能的假设。根据数据收集情况对结果进行了讨论,这是基于横截面设置,假设消费者对商品的了解,并根据假设强制回答。结果表明,尽管外生变量发生了重大变化,感知有用性(PU)和感知易用性(PEOU)之间的方差水平差异符合TAM3。因此,PU是行为意图(BI)的最强预测因子,支持影响PU的结构选择。这也表明有用性大于易用性。研究结果表明,每个变量类别对PU和PEOU都有有利的影响。具体来说,认知工具过程(CIP)和价值相关方面(VRA)是PU的重要预测因子,其中CIP是最关键的驱动因素,强调消费者行为是由与生活方式相关的因素驱动的,趋势,和价格。VRA_1对PU的影响最强,强调功能成分的高潜力,如维生素。此外,结果表明,锚定变量比调整变量对PEOU的影响更大,强调享受和放纵消费品的重要性,尤其是去茶。这些发现表明,经过实证检验和调整的CGAM为衡量消费品的接受度和确定关键驱动因素提供了坚实的基础。
    The technology acceptance model (TAM) has not been applied beyond the technological context, despite its widespread applications. This study extends the TAM to consumer goods and validates the conceptualised consumer goods acceptance model (CGAM) using tea-to-go as a proxy for consumer goods. An exploratory research approach based on a quota sample is used to adjust and test the CGAM, showing that the adjusted CGAM and its measures are reliable and valid, thus supporting the hypothesis that extending the TAM to a non-technological context is possible. The results are discussed in light of the data collection, which is based on a cross-sectional setting, assuming consumers\' knowledge of the good and forcing answers based on assumptions. The results show that despite major changes to the exogenous variables, the difference in variance levels between perceived usefulness (PU) and perceived ease of use (PEOU) is in accordance with TAM 3. Thus, PU is the strongest predictor of behavioural intention (BI), supporting the choice of constructs influencing PU. This also indicates that usefulness outweighs ease of use. The findings demonstrate that each variable category has a favourable influence on PU and PEOU. Specifically, cognitive instrumental processes (CIP) and value-related aspects (VRA) are significant predictors of PU, whereas CIP is the most critical driver, highlighting that consumer actions are driven by factors correlated with lifestyle, trends, and price. VRA_1 had the strongest impact on PU, accentuating the high potential of functional ingredients, such as vitamins. Furthermore, the results show that the anchor variables have a stronger impact on PEOU than the adjustment variables, emphasising the importance of enjoyment and indulgence in consumer goods, especially tea-to-go. These findings show that the empirically tested and adjusted CGAM provides a solid basis for measuring the acceptance of consumer goods and identifying key drivers.
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  • 文章类型: Journal Article
    背景:社会养老金,农村老年人社会救助制度,已经在许多国家实施,并对健康产生了积极影响。中国社会养老金计划的长期健康后果尚不确定。这项研究的目的是评估新农村社会养老金(NRSP)对中国农村老年人的长期健康影响。
    方法:基于2011年和2018年中国健康与退休纵向研究,我们比较了农村老年人参与NRSP前后8个健康相关生活质量(HRQoL)分量表的得分.在数据分析中使用倾向得分匹配和差异差异方法。我们还对具有不同特征和养老金入学时间的亚组进行了异质性分析。
    结果:NRSP显著提高了身体机能评分,角色-物理,农村老年参与者的心理健康自我评估为1.90(p<0.01),2.05(p<0.01),和2.93(p<0.05),分别。在排除新登记的个人后,NRSP的有益健康影响仍然显著。在农村老年人的HRQoL子量表上的其他五个得分中,由于NRSP而没有显着变化。NRSP对没有正规教育的欠发达地区的老年人有更多的健康益处。
    结论:NRSP减少了健康差距,对农村老年人的身心健康有长期益处。我们建议在整个中国农村不断扩大NRSP,并进一步完善社会支持系统,以提高农村老年人的整体生活质量。针对弱势群体的可比社会养老金计划也可以在其他低收入或中等收入国家进行。
    BACKGROUND: Social pensions, social assistance systems for older people in rural areas, have been put into place in many nations and have positively impacted health. The long-term health consequences of social pension programs in China are uncertain. The aim of this study is to evaluate the long-term health consequences of the new rural social pension (NRSP) for the rural older people in China.
    METHODS: Based on the 2011 and 2018 China Health and Retirement Longitudinal Study, we compared the scores on eight Health-Related Quality of Life (HRQoL) subscales of the rural older people before and after participation in the NRSP. The propensity score matching and difference-in-difference methods were used in data analysis. We also conducted a heterogeneity analysis for subgroups with different characteristics and pension enrolment times.
    RESULTS: The NRSP significantly enhanced scores on physical functioning, role-physical, and self-rated mental health of old rural participants by 1.90 (p < 0.01), 2.05 (p < 0.01), and 2.93 (p < 0.05), respectively. After excluding newly enrolled individuals, the beneficial health effects of the NRSP remained significant. There were no significant changes due to NRSP in the other five scores on the HRQoL subscale of the rural older people. The NRSP had more health benefits for older people in underdeveloped areas without formal schooling.
    CONCLUSIONS: The NRSP reduced health disparities and had long-term benefits on the physical and mental health of the rural older people. We suggest continuously expanding the NRSP throughout rural China and further improving the social support system to enhance the overall quality of life of the rural older people. Comparable social pension programs aimed at underprivileged groups could also be conducted in other low- or middle-income nations.
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  • 文章类型: Editorial
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  • 文章类型: Journal Article
    “开放科学”倡导开放科学研究,以及共享数据,分析计划和代码,以实现结果的复制。然而,这些要求通常无法解释定量和定性研究之间的方法差异,和严重的道德问题提出了建议,即完整的定性数据集可以或应该与定性研究论文一起发布。除了重要的伦理问题,共享定性数据以实现复制的想法在概念上与大多数定性方法的基础不一致,这凸显了研究者独特解释功能的重要性。定性数据的二次分析是否可以接受的问题是关键,在这篇评论中,我们认为有很好的概念,考虑资助者的道德和经济原因,研究人员和出版商可以更好地利用现有数据。
    \'Open Science\' advocates for open access to scientific research, as well as sharing data, analysis plans and code in order to enable replication of results. However, these requirements typically fail to account for methodological differences between quantitative and qualitative research, and serious ethical problems are raised by the suggestion that full qualitative datasets can or should be published alongside qualitative research papers. Aside from important ethical concerns, the idea of sharing qualitative data in order to enable replication is conceptually at odds with the underpinnings on most qualitative methodologies, which highlight the importance of the unique interpretative function of the researcher. The question of whether secondary analysis of qualitative data is acceptable is key, and in this commentary we argue that there are good conceptual, ethical and economic reasons to consider how funders, researchers and publishers can make better use of existing data.
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  • 文章类型: Journal Article
    行为科学的研究人员通常对纵向行为变化结果以及影响这些结果随时间变化的机制感兴趣。通常用于解决这些研究问题的统计模型不允许调查随时间动态变化的机制。然而,潜在变化得分模型允许随时间的动态变化(不仅仅是线性或指数变化),并且在参数约束方面具有其他纵向模型所没有的灵活性。发展研究人员还经常利用中介分析来研究在路径分析或潜在增长曲线模型中实施的纵向研究中的影响机制。在这篇文章中,我们提供了三个示例,说明如何通过将传统中介模型的各方面与具有两个以上时间点的重复测量结果(以及中介和预测因子)的潜在变化评分模型相结合,在潜在变化评分框架中测试中介.我们还提供了Mplus语法来完成这些分析以及潜在变化分数中介(LCSM)模型的实际考虑。
    Researchers in behavioral sciences are often interested in longitudinal behavior change outcomes and the mechanisms that influence changes in these outcomes over time. The statistical models that are typically implemented to address these research questions do not allow for investigation of mechanisms of dynamic change over time. However, latent change score models allow for dynamic change (not just linear or exponential change) over time and have flexibility in parameter constraints that other longitudinal models do not have. Developmental researchers also frequently utilize mediation analyses to investigate mechanisms of influence in longitudinal research implemented in path analytic or latent growth curve models. In this article, we provide three examples of how mediation can be tested in the latent change score framework by combining aspects of traditional mediation models with latent change score models of repeated measures outcomes (and mediators and predictors) with more than two timepoints. We also provide the Mplus syntax to complete these analyses and practical considerations of latent change score mediation (LCSM) models.
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  • 文章类型: Journal Article
    未知如何共同思考,或坚持与他人的问题或感情,展现在浪漫情侣的日常生活中。对来自14天二元日记的数据使用方差分解程序,我们评估了共同反推的方差有多大归因于时间稳定和变化的因素,以及共同思考是否更好地衡量为夫妇水平或个人水平的过程。人内,共同反推中的夫妻内部波动对总方差的贡献最大(〜33%),基于这些波动的汇总分数是可靠的。稳定的夫妇之间的差异占总方差的约14%,也可以可靠地评估。然而,共同反省中的夫妻内部协议较低,因此,在夫妇内部变化水平上的可靠性是不够的。需要进行研究以了解这些对共同思考和潜在下游后果的不同看法。最后,我们考虑了这些结果如何为理论提供信息,并可以应用于类似的二元结构。
    It is unknown how co-rumination, or perseverating on problems or feelings with another person, unfolds in the daily lives of romantic couples. Using a variance decomposition procedure on data from a 14-day dyadic diary, we assessed how much variance in co-rumination was attributable to temporally stable and varying factors, as well as whether co-rumination is better measured as a couple-level or individual-level process. Within-person, within-couple fluctuations in co-rumination contributed most (~33%) to the total variance and summary scores based on these fluctuations were reliable. Stable between-couple differences accounted for ~14% of the total variance and could also be reliably assessed. However, within-couple agreement in co-rumination was low, such that the reliability at the level of within-couple change was inadequate. Research is needed to understand these divergent perceptions of co-rumination and potential downstream consequences. We conclude by considering how these results inform theory and can be applied to similar dyadic constructs.
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  • 文章类型: Journal Article
    从历史上看,对经胫骨承窝和使用者之间的耦合进行评估是基于临床医生的观察和经验,但可能是不准确和不可靠的。因此,我们提出了一个概念证明,对于插座的六个可能的自由度耦合公制系统中的五个,使用在3D打印肢体替代品上校准的运动分析。该方法与任何插座悬挂方法兼容,并且不需要预先修改插座。使用校准试验来定位膝关节的旋转轴,该旋转轴与大腿上的标记簇相对应;尽管整个残留物被插座遮挡,但在测试试验期间仍可以识别肢体。发现该技术的误差在位移0.7毫米和旋转0.7度以内,基于控制数据。动态测试显示,对于所有度量,时间步长间方差的四分位数间范围(IQR)<0.5mm/deg。该方法可以形成客观套接字评估的基础,改善截肢者的临床实践和生活质量。
    Assessment of coupling between transtibial sockets and users is historically based on clinicians\' observations and experience, but can be inaccurate and unreliable. Therefore, we present a proof of concept, for five out of six possible degrees of freedom coupling metric system for a socket, using motion analysis calibrated on a 3D printed limb substitute. The method is compatible with any socket suspension method and does not require prior modifications to the socket. Calibration trials were used to locate the axis of rotation of the knee joint referenced against a marker cluster on the thigh; this allowed for the identification of the limb during test trials despite the entire residuum being obscured from view by the socket. The error in the technique was found to be within 0.7 mm in displacement and 0.7 degrees in rotation, based on the control data. Dynamic testing showed the Inter Quartile Range (IQR) of inter time step variance was <0.5 mm/deg for all metrics. The method can form a basis for objective socket evaluation, improve clinical practice and the quality of life for amputees.
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