Statistical model

统计模型
  • 文章类型: Journal Article
    同源蛋白质序列的统计分析可以鉴定共同进化以产生具有不同性质的家族成员的氨基酸残基位置。基于残基位置的协同进化是维持蛋白质结构所必需的假设,统计模型揭示的共同进化特征提供了对残基-残基相互作用的深入了解,这对于在分子水平上理解蛋白质机制很重要。随着便于统计分析的基因组测序数据库的快速扩展,这种基于序列的方法已被用于研究广泛的蛋白质家族.这种方法的新兴应用是设计混合转录调节因子作为模块化遗传传感器,用于输入信号和遗传元件之间的新型布线以控制输出。在许多变构调节的调节家族中,成员包含结构保守和功能独立的蛋白质结构域,包括用于与特定遗传元件相互作用的DNA结合模块(DBM)和用于感测输入信号的配体结合模块(LBM)。通过将来自两个不同家族成员的DBM和LBM杂交,可以创建具有天然系统中不存在的信号检测和DNA识别特性的新组合的混合调节剂。在这次审查中,我们介绍了混合调节器的最新进展及其在细胞工程中的应用,特别是侧重于使用统计分析来表征DBM-LBM相互作用和混合调节器设计。基于这些研究,然后,我们讨论了当前的局限性和潜在的方向,以提高这种基于序列的设计方法的影响。
    Statistical analyses of homologous protein sequences can identify amino acid residue positions that co-evolve to generate family members with different properties. Based on the hypothesis that the coevolution of residue positions is necessary for maintaining protein structure, coevolutionary traits revealed by statistical models provide insight into residue-residue interactions that are important for understanding protein mechanisms at the molecular level. With the rapid expansion of genome sequencing databases that facilitate statistical analyses, this sequence-based approach has been used to study a broad range of protein families. An emerging application of this approach is to design hybrid transcriptional regulators as modular genetic sensors for novel wiring between input signals and genetic elements to control outputs. Among many allosterically regulated regulator families, the members contain structurally conserved and functionally independent protein domains, including a DNA-binding module (DBM) for interacting with a specific genetic element and a ligand-binding module (LBM) for sensing an input signal. By hybridizing a DBM and an LBM from two different family members, a hybrid regulator can be created with a new combination of signal-detection and DNA-recognition properties not present in natural systems. In this review, we present recent advances in the development of hybrid regulators and their applications in cellular engineering, especially focusing on the use of statistical analyses for characterizing DBM-LBM interactions and hybrid regulator design. Based on these studies, we then discuss the current limitations and potential directions for enhancing the impact of this sequence-based design approach.
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  • 文章类型: Journal Article
    生物医学物理数据在促进我们对人类健康的理解方面的关键作用强调了它的重要性。解开疾病的潜在机制,并促进创新医疗和干预措施的发展。这些数据是一种基本资源,赋予研究人员权力,医疗保健专业人员,和科学家做出明智的决定,先锋研究,并最终提高全球医疗保健质量和个人福祉。它是不断追求医疗进步和改善医疗保健结果的基石。本文旨在解决当应用于从初始故障发生中删失的渐进生物医学数据时,估计与修改的Weibull分布相关的未知参数和可靠性度量方面的挑战。在这种情况下,本文提出了经典和贝叶斯技术来推导未知参数的估计,生存,和故障率函数。贝叶斯估计是在考虑非对称和对称损失函数的情况下计算的。采用马尔可夫链蒙特卡罗方法来获得这些贝叶斯估计及其相应的最高后验密度可信区间。由于这些估计器固有的复杂性,这在理论上是无法比较的,进行了一项模拟研究,以评估各种估计程序的性能。此外,一系列的优化标准被用来确定最有效的渐进控制策略。最后,本文介绍了一个医学应用来说明所提出的估计量的有效性。数值结果表明,贝叶斯估计通过实现最小的均方根误差和更窄的间隔长度而优于其他估计方法。
    The importance of biomedical physical data is underscored by its crucial role in advancing our comprehension of human health, unraveling the mechanisms underlying diseases, and facilitating the development of innovative medical treatments and interventions. This data serves as a fundamental resource, empowering researchers, healthcare professionals, and scientists to make informed decisions, pioneer research, and ultimately enhance global healthcare quality and individual well-being. It forms a cornerstone in the ongoing pursuit of medical progress and improved healthcare outcomes. This article aims to tackle challenges in estimating unknown parameters and reliability measures related to the modified Weibull distribution when applied to censored progressive biomedical data from the initial failure occurrence. In this context, the article proposes both classical and Bayesian techniques to derive estimates for unknown parameters, survival, and failure rate functions. Bayesian estimates are computed considering both asymmetric and symmetric loss functions. The Markov chain Monte Carlo method is employed to obtain these Bayesian estimates and their corresponding highest posterior density credible intervals. Due to the inherent complexity of these estimators, which cannot be theoretically compared, a simulation study is conducted to evaluate the performance of various estimation procedures. Additionally, a range of optimization criteria is utilized to identify the most effective progressive control strategies. Lastly, the article presents a medical application to illustrate the effectiveness of the proposed estimators. Numerical findings indicate that Bayesian estimates outperform other estimation methods by achieving minimal root mean square errors and narrower interval lengths.
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  • 文章类型: Journal Article
    5-甲基胞嘧啶(m5c)是修饰的胞嘧啶碱基,其由于在碳的5位添加甲基而形成。这种修饰是在几乎所有类型的RNA中发生的最常见的PTM之一。常规的实验室方法不能快速可靠地识别m5c位点。然而,序列数据的就绪性使得开发计算智能模型变得可行,这些模型可以优化识别过程,从而提高准确性和鲁棒性。本研究的重点是使用深度学习模型构建的计算机方法的开发。然后将编码数据输入深度学习模型,其中包括门控经常性单位(GRU),长短期记忆(LSTM),和双向LSTM(Bi-LSTM)。之后,这些模型经过严格的评估过程,包括独立的集合检验和10倍交叉验证.结果表明,基于LSTM的模型,m5c-iDeep,与现有的m5c预测因子相比,表现优于99.9%的准确率。为了方便研究人员,m5c-iDeep还部署在基于Web的服务器上,该服务器可在https://taseersuleman-m5c-ideep-m5c-ideep访问。流光。app/.
    5-Methylcytosine (m5c) is a modified cytosine base which is formed as the result of addition of methyl group added at position 5 of carbon. This modification is one of the most common PTM that used to occur in almost all types of RNA. The conventional laboratory methods do not provide quick reliable identification of m5c sites. However, the sequence data readiness has made it feasible to develop computationally intelligent models that optimize the identification process for accuracy and robustness. The present research focused on the development of in-silico methods built using deep learning models. The encoded data was then fed into deep learning models, which included gated recurrent unit (GRU), long short-term memory (LSTM), and bi-directional LSTM (Bi-LSTM). After that, the models were subjected to a rigorous evaluation process that included both independent set testing and 10-fold cross validation. The results revealed that LSTM-based model, m5c-iDeep, outperformed revealing 99.9 % accuracy while comparing with existing m5c predictors. In order to facilitate researchers, m5c-iDeep was also deployed on a web-based server which is accessible at https://taseersuleman-m5c-ideep-m5c-ideep.streamlit.app/.
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  • 文章类型: Journal Article
    背景:Budd-Chiari综合征(BCS)主要是肝静脉阻塞的疾病,这涉及血液回流到肝脏。尽管有许多原因与这种疾病有关,最常见的是,它是由于高凝状态和血液紊乱而发生的。最近,关于早期诊断和各种治疗方式的知识迅速传播,这使得在大多数情况下能够预防死亡。这主要是通过在各种期刊上发表的研究文章传播的。因此,本文旨在比较性别趋势比,以确定与该疾病有关的文章的主要作者的男性和女性作者贡献方面的相关差异.方法:使用2013年至2022年的PubMed数据库进行文献计量分析。NamSor分析了主要作者的性别,应用程序编程接口(API)。采用R软件进行统计分析,ARIMA模型,和图形是使用Datawrapper准备的。
    结果:在提取的667篇文章中,分析显示,有455名(68.2%)男性第一作者和212名(31.8%)女性第一作者。我们还制定了其他各种结果,其中描绘了更高的女性与男性作者比例,包括各种期刊和不同的国家。尽管男性作者与女性作者相比有增加的趋势,这项研究发现,男性作者对这种疾病的研究仍然较高。
    结论:这项研究表明,有必要引起人们对出版物中男性偏袒女性的不公平制度的关注。进行的预测分析还有助于预见未来几年的趋势,并解释了解决医疗保健系统中男女之间差异的必要性。
    BACKGROUND: Budd-Chiari syndrome (BCS) is primarily a disease of hepatic vein blockage, which involves a backflow of blood to the liver. Although there have been many causes linked to this disease, most commonly, it occurs due to hypercoagulable states and blood disorders. In recent times, there has been a fast spread of knowledge regarding early diagnosis and various treatment modalities, which has enabled the prevention of mortality in most cases. This has primarily spread through research articles published in various journals. Thus, the article aims to compare the gender trend ratios to identify the associated discrepancies in terms of male and female author contributions who have been the primary authors for articles pertaining to this disease.  Methodology: A PubMed database between the years 2013 and 2022 was used for the bibliometric analysis. The gender of the primary author was analyzed by NamSor, an application programming interface (API). The statistical analysis was conducted using R software, the ARIMA model, and graphs were prepared using Datawrapper.
    RESULTS: Out of 667 articles extracted, the analysis showed that there were 455 (68.2%) first male authors and 212 (31.8%) first female authors. We also formulated various other results, which depicted a higher female-to-male author ratio including various journals and different countries. Although there has been an increasing trend of male authors as compared to female authors, this study found that male authorship for research on this disease is still higher.
    CONCLUSIONS: This study depicts that there is a necessity to draw attention to the inequitable systems favoring men over women for publications. The predictive analysis conducted also helps to foresee the trend in the next few years and explains the necessity of addressing the disparities among both genders in healthcare systems.
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  • 文章类型: Journal Article
    虽然促进健康饮食是一个政策目标,饮食习惯的可管理性仍然不确定。个人饮食模式反映了许多因素,其中一些对个人来说是相对容易管理的,而另一些则不是。在这篇文章中,假设在观察到的食物消费模式中包含有关饮食习惯可管理性的某种信息,我们专注于自己的饮食习惯。我们引入了食物频率问卷数据的统计描述性模型,估计食品之间的成对联系的强度,并通过将社区检测应用于估计的食物间联系网络来对食物进行分组。这些联系代表了食物对在消费中的共同运动。此外,我们分析了心理健康和饮食习惯之间的关系,考虑到饮食习惯的可管理性。利用日本的一项观察性研究,我们获得了以下结果:115种食品分为三组,但是组成因性别而异;在身心健康分析中,一些应激反应项目与对其中一些食物分组的依赖相关(例如,“极度疲劳”与含有西红柿的一组呈负相关,黄瓜,普通话,等。,对于女性受试者)。由于根据我们的估计对食品进行分组,因此描述了饮食习惯的内部结构,健康饮食政策可以将其视为约束,因此,我们应该按照与该分组相同的思路设计这样的政策。
    Although promoting healthy eating is a policy objective, the manageability of dietary habits remains uncertain. Personal dietary patterns reflect many factors, some of which are relatively manageable for individuals whilst others are not. In this article, assuming that some sort of information about the manageability of dietary habits is contained in the observed patterns of food consumption, we focused on dietary patterns on their own. We introduced a statistical descriptive model for data from a food frequency questionnaire, estimated the strength of pairwise linkage between foodstuffs, and grouped foodstuffs by applying community detection to the networks of the estimated inter-food linkages. Those linkages represent the co-movement of pairs of food in consumption. Furthermore, we demonstrated an analysis of the relationship between mental health and dietary habits, considering the aspect of the manageability of dietary habits. Using an observational study in Japan, we obtained the following results: 115 foodstuffs were divided into three groups for both genders, but the compositions were different by gender; in the analysis of mental and physical health, some stress response items were associated with a dependence on some of those food groupings (e.g., \"extremely tired\" was negatively associated with a group containing tomatoes, cucumber, mandarin, etc., for female subjects). As the grouping of foodstuffs based on our estimation depicted an internal structure of dietary habit that a healthy eating policy could regard as a constraint, it follows that we should design such a policy along the same lines as that grouping.
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  • 文章类型: Journal Article
    识别痴呆症高危人群对于优化临床护理至关重要,制定有效的预防策略,并确定临床试验的资格。自我们在2010年和2015年进行系统评价以来,痴呆症风险预测模型激增。这项研究的目的是更新我们以前的评论,批判性审查,痴呆症风险建模的新进展。
    MEDLINE,Embase,Scopus,和WebofScience于2014年3月至2022年6月进行了搜索。如果研究是基于人群或社区的队列(包括电子健康记录数据),开发了一个预测晚期痴呆的模型,并包括模型性能指数,如歧视,校准,或外部验证。
    总共,从电子搜索中识别出9209篇文章,其中74人符合纳入标准。我们发现,自2014年以来,发布的新车型数量大幅增加(>50款新车型),包括使用机器学习开发的模型数量的增加。已经测试了450多个独特的预测变量(分量)。19项研究(26%)对新开发或现有模型进行了外部验证,结果喜忧参半。第一次,还在低收入和中等收入国家(LMICs)开发了模型,并在种族和少数族裔群体中验证了其他模型。
    关于痴呆风险预测模型的文献随着新的分析发展和LMIC的测试而迅速发展。然而,就哪一种模型最适合临床常规使用提出建议仍具有挑战性.迫切需要开发一种合适的,健壮,在普通人群中验证的风险预测模型,可以在临床实践中广泛实施,以提高痴呆的预防。
    UNASSIGNED: Identifying individuals at high risk of dementia is critical to optimized clinical care, formulating effective preventative strategies, and determining eligibility for clinical trials. Since our previous systematic reviews in 2010 and 2015, there has been a surge in dementia risk prediction modelling. The aim of this study was to update our previous reviews to explore, and critically review, new developments in dementia risk modelling.
    UNASSIGNED: MEDLINE, Embase, Scopus, and Web of Science were searched from March 2014 to June 2022. Studies were included if they were population- or community-based cohorts (including electronic health record data), had developed a model for predicting late-life incident dementia, and included model performance indices such as discrimination, calibration, or external validation.
    UNASSIGNED: In total, 9,209 articles were identified from the electronic search, of which 74 met the inclusion criteria. We found a substantial increase in the number of new models published from 2014 (>50 new models), including an increase in the number of models developed using machine learning. Over 450 unique predictor (component) variables have been tested. Nineteen studies (26%) undertook external validation of newly developed or existing models, with mixed results. For the first time, models have also been developed in low- and middle-income countries (LMICs) and others validated in racial and ethnic minority groups.
    UNASSIGNED: The literature on dementia risk prediction modelling is rapidly evolving with new analytical developments and testing in LMICs. However, it is still challenging to make recommendations about which one model is the most suitable for routine use in a clinical setting. There is an urgent need to develop a suitable, robust, validated risk prediction model in the general population that can be widely implemented in clinical practice to improve dementia prevention.
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  • 文章类型: Journal Article
    目的:本研究旨在使用韩国医学检查中的真实和模拟数据,比较和评估两种停止规则(SEM0.3和0.25)下的计算机自适应测试(CAT)的效率和准确性。
    方法:本研究采用事后模拟和真实数据分析来探索医学检查中CAT的最佳停止规则。真实数据来自哈勒姆大学医学院2020年考试期间三年级医学生的反应。模拟数据是使用R中真实项目库的估计参数生成的。结果变量包括通过或失败的受试者数量,SEM值为0.25和0.30,管理的项目数,和相关性。通过基于0.0的切分检查通过或失败的一致性来评估真实CAT结果的一致性。通过比较两种停止规则下管理的物品的平均数量来评估所有CAT设计的效率。
    结果:SEM0.25和SEM0.30均在CAT中提供了准确性和效率之间的良好平衡。实际数据显示,两种SEM条件之间的通过/失败结果差异最小,能力估计之间的相关性很高(r=0.99)。模拟结果证实了这些发现,表示真实数据和模拟数据之间相似的平均项目编号。
    结论:研究结果表明,在Rasch模型的背景下,SEM0.25和0.30都是有效的终止标准,在CAT中平衡准确性和效率。
    OBJECTIVE: This study aimed to compare and evaluate the efficiency and accuracy of computerized adaptive testing (CAT) under two stopping rules (SEM 0.3 and 0.25) using both real and simulated data in medical examinations in Korea.
    METHODS: This study employed post-hoc simulation and real data analysis to explore the optimal stopping rule for CAT in medical examinations. The real data were obtained from the responses of 3rd-year medical students during examinations in 2020 at Hallym University College of Medicine. Simulated data were generated using estimated parameters from a real item bank in R. Outcome variables included the number of examinees\' passing or failing with SEM values of 0.25 and 0.30, the number of items administered, and the correlation. The consistency of real CAT result was evaluated by examining consistency of pass or fail based on a cut score of 0.0. The efficiency of all CAT designs was assessed by comparing the average number of items administered under both stopping rules.
    RESULTS: Both SEM 0.25 and SEM 0.30 provided a good balance between accuracy and efficiency in CAT. The real data showed minimal differences in pass/fail outcomes between the 2 SEM conditions, with a high correlation (r = 0.99) between ability estimates. The simulation results confirmed these findings, indicating similar average item numbers between real and simulated data.
    CONCLUSIONS: The findings suggest that both SEM 0.25 and 0.30 are effective termination criteria in the context of the Rasch model, balancing accuracy and efficiency in CAT.
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  • 文章类型: Journal Article
    目的:已知边缘性人格障碍(BPD)与多种人格障碍(PD)具有共同特征,并表现出多种防御机制模式。为了增强我们对BPD的了解,将我们的重点从传统的分类诊断转移到与其他PD共享的维度特征是至关重要的,正如边缘人格组织(BPO)模型所暗示的那样。这种方法照亮了BPD特征的细微光谱,对其复杂性提供更深入的见解。虽然有研究调查了BPD与其他PD的共病,探索各种人格因素与BPD自身防御机制之间关系的研究很少。本研究旨在调查被诊断为BPD的个体中各种人格因素与防御方式之间的复杂相互关系。
    方法:使用网络分析方法,使用防御方式问卷和人格障碍问卷-4+对227例诊断为BPD的患者的数据进行评估。
    结果:在人格因素和防御方式之间观察到了错综复杂的联系。各种人格因素和防御风格之间存在显着关联,防御风格不成熟,例如,自适应不良和图像失真在中心性分析中在BPD中尤为突出。适应不良的防御方式具有最高的预期影响中心性。此外,分裂型,依赖,自恋人格因素在网络中表现出相对较高的中心性。
    结论:网络分析可以有效地描述各种PD和防御方式的复杂性。这些发现预计将有助于更深入地理解为什么BPD表现出不同的组织水平,并呈现出异质特征,与BPO提出的观点一致。
    OBJECTIVE: Borderline personality disorder (BPD) is known to share characteristics with a variety of personality disorders (PDs) and exhibits diverse patterns of defense mechanisms. To enhance our understanding of BPD, it\'s crucial to shift our focus from traditional categorical diagnostics to the dimensional traits shared with other PDs, as the borderline personality organization (BPO) model suggests. This approach illuminates the nuanced spectrum of BPD characteristics, offering deeper insights into its complexity. While studies have investigated the comorbidity of BPD with other PDs, research exploring the relationship between various personality factors and defense mechanisms within BPD itself has been scarce. The present study was undertaken to investigate the complex interrelationships between various personality factors and defense styles in individuals diagnosed with BPD.
    METHODS: Using a network analysis approach, data from 227 patients diagnosed with BPD were examined using the Defense Style Questionnaire and Personality Disorder Questionnaire-4+ for assessment.
    RESULTS: Intricate connections were observed between personality factors and defense styles. Significant associations were identified between various personality factors and defense styles, with immature defense styles, such as maladaptive and image-distorting being particularly prominent in BPD in the centrality analysis. The maladaptive defense style had the highest expected influence centrality. Furthermore, the schizotypal, dependent, and narcissistic personality factors demonstrated relatively high centrality within the network.
    CONCLUSIONS: Network analysis can effectively delineate the complexity of various PDs and defense styles. These findings are expected to facilitate a deeper understanding of why BPD exhibits various levels of organization and presents with heterogeneous characteristics, consistent with the perspectives proposed by the BPO.
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  • 文章类型: Journal Article
    提出了基于XGBoost的微污染物超声降解动力学常数预测模型。通过迭代优化参数后,该模型实现了R2和SMAPE达到0.99和2.06%的评估指标,分别。使用Shapley添加剂解释(SHAP)评估了设计参数对预测痕量污染物超声降解动力学常数的影响。结果表明,功率密度和频率显着影响预测性能。基于功率密度和频率值对数据库进行排序。随后,800个原始数据被分成每个200个小数据库。在确认减小数据库大小不会影响预测准确性之后,对五种污染物进行了超声降解实验,产生实验数据。选择了具有数值范围内的实验条件的小型数据库。过滤了满足两个特征条件的数据,导致一个优化的60数据组。纳入实验数据后,训练了一个模型进行预测。将实验的降解动力学常数(kE)与预测常数(基于800个数据的模型:kP-800和基于60个数据的模型:kP-60)进行了比较。结果显示布洛芬,双酚A,卡马西平,和17β-雌二醇在60数据组中表现更好(kP-60/kE:1.00、0.99、1.00、1.00),而咖啡因适合在800数据组中训练的模型(kP-800/kE:1.02)。
    A prediction model based on XGBoost is proposed for ultrasonic degradation of micropollutants\' kinetic constants. After parameter optimization through iteration, the model achieves Evaluation metrics with R2 and SMAPE reaching 0.99 and 2.06%, respectively. The impact of design parameters on predicting kinetic constants for ultrasound degradation of trace pollutants was assessed using Shapley additive explanations (SHAP). Results indicate that power density and frequency significantly impact the predictive performance. The database was sorted based on power density and frequency values. Subsequently, 800 raw data were split into small databases of 200 each. After confirming that reducing the database size doesn\'t affect prediction accuracy, ultrasound degradation experiments were conducted for five pollutants, yielding experimental data. A small database with experimental conditions within the numerical range was selected. Data meeting both feature conditions were filtered, resulting in an optimized 60-data group. After incorporating experimental data, a model was trained for prediction. Degradation kinetic constants for experiments (kE) were compared with predicted constants (for 800 data-based model: kP-800 and for 60 data-based model: kP-60). Results showed ibuprofen, bisphenol A, carbamazepine, and 17β-Estradiol performed better on the 60-data group (kP-60/kE: 1.00, 0.99, 1.00, 1.00), while caffeine suited the model trained on the 800-data group (kP-800/kE: 1.02).
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  • 文章类型: Editorial
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