inference

推理
  • 文章类型: Journal Article
    否定触发的推论在人类语言中是普遍的。听到“这不是X”应该在逻辑上导致推断X以外的所有元素构成可能的替代方案。然而,并非所有逻辑上可能的替代方案在现实世界中都是平等的。作为一个合理的替代方案,它必须与否定元素尽可能多的相似之处,最合理的一个通常来自与否定元素相同的分类类别。本文报道了两个实验,这些实验调查了学龄前儿童推断由否定引发的合理替代方案的能力的发展。实验1表明,在要求儿童确定否定元素的最合理替代方案的情况下,3-,4岁和5岁的孩子,表现出对分类关联的强烈偏好。实验2进一步证明了3-,在没有明确要求他们评估不同候选人的合理性的情况下,4岁和5岁的孩子将所有补集成员视为同等可能的替代方案。一起来看,我们的发现揭示了学龄前儿童对由否定引发的合理选择做出推论的能力的有趣的发展连续性。我们讨论了潜在的语义和语用因素,这些因素有助于儿童对负面表达引发的典型替代方案的新兴意识。
    Negation-triggered inferences are universal across human languages. Hearing \"This is not X\" should logically lead to the inference that all elements other than X constitute possible alternatives. However, not all logically possible alternatives are equally accessible in the real world. To qualify as a plausible alternative, it must share with the negated element as many similarities as possible, and the most plausible one is often from the same taxonomic category as the negated element. The current article reports on two experiments that investigated the development of preschool children\'s ability to infer plausible alternatives triggered by negation. Experiment 1 showed that in a context where children were required to determine the most plausible alternative to the negated element, the 3-, 4- and 5-year-olds, exhibited a robust preference for the taxonomic associates. Experiment 2 further demonstrated that the 3-, 4- and 5-year-olds considered all the complement set members as equally possible alternatives in a context where they were not explicitly required to evaluate the plausibility of different candidates. Taken together, our findings reveal interesting developmental continuity in preschool children\'s ability to make inferences about plausible alternatives triggered by negation. We discuss the potential semantic and pragmatic factors that contribute to children\'s emerging awareness of typical alternatives triggered by negative expressions.
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  • 文章类型: Journal Article
    基因调控网络(GRN)结构的确定是生物学中的核心问题,有多种推理方法可用于不同类型的数据。对于一个广泛流行和具有挑战性的用例,即在未知联合分布的多个时间点干预后测量的单细胞基因表达数据,只有一种已知的专门开发的方法,,它不能充分利用此数据类型中包含的丰富信息。在这种情况下,我们为GRN开发了一种推理方法,网络影响协方差动态,被称为WENDY。WENDY的核心思想是对协方差矩阵的动力学进行建模,并将此动态作为优化问题来解决,以确定监管关系。为了评估其有效性,我们使用合成数据和实验数据将WENDY与其他推断方法进行了比较。我们的结果表明,WENDY在不同的数据集上表现良好。
    Determining gene regulatory network (GRN) structure is a central problem in biology, with a variety of inference methods available for different types of data. For a widely prevalent and challenging use case, namely single-cell gene expression data measured after intervention at multiple time points with unknown joint distributions, there is only one known specifically developed method, which does not fully utilize the rich information contained in this data type. We develop an inference method for the GRN in this case, netWork infErence by covariaNce DYnamics, dubbed WENDY. The core idea of WENDY is to model the dynamics of the covariance matrix, and solve this dynamics as an optimization problem to determine the regulatory relationships. To evaluate its effectiveness, we compare WENDY with other inference methods using synthetic data and experimental data. Our results demonstrate that WENDY performs well across different data sets.
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  • 文章类型: Journal Article
    COVID-19大流行证明了流行病学和建模在分析传染病威胁和实时支持决策方面发挥的关键作用。由于大流行期间产生的数据数量和广度前所未有,我们回顾了现代分析机会,以解决在重大现代流行病期间出现的问题。遵循所需见解的广泛时间顺序-从理解初始动态到对干预措施的回顾性评估,我们描述了每种方法的理论基础和潜在的直觉。通过一系列的案例研究,我们说明现实生活中的应用,并讨论对未来工作的影响。
    The COVID-19 pandemic demonstrated the key role that epidemiology and modelling play in analysing infectious threats and supporting decision making in real-time. Motivated by the unprecedented volume and breadth of data generated during the pandemic, we review modern opportunities for analysis to address questions that emerge during a major modern epidemic. Following the broad chronology of insights required - from understanding initial dynamics to retrospective evaluation of interventions, we describe the theoretical foundations of each approach and the underlying intuition. Through a series of case studies, we illustrate real life applications, and discuss implications for future work.
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  • 文章类型: Journal Article
    优势是指杂合基因型相对于两种纯合基因型的影响。适应性突变的优势程度可以对有害和有益的突变随时间的频率变化以及围绕此类选定等位基因的连锁中性遗传变异的模式产生深远的影响。因为支配地位是这样一个基本概念,它在整个人口遗传学历史上受到了极大的关注。费希尔的早期工作,Wright,霍尔丹专注于理解优势存在的概念基础。最近的工作试图通过估计突变的优势效应来测试这些理论和概念模型。然而,众所周知,估算优势系数具有挑战性,并且在有限的研究中只在少数物种中进行过。在这次审查中,我们首先描述一些早期的理论和概念模型,以理解支配存在的机制。第二,我们讨论了几种估计优势系数的方法,并总结了优势系数的估计。我们注意到不同物种观察到的趋势,突变类型,和基因的功能类别。通过比较不同类型基因的优势系数的估计,我们检验了几个存在优势的假设。最后,我们讨论了优势如何影响种群中有益和有害突变的动态,以及有害突变的优势程度如何影响近亲繁殖对适应性的影响.
    Dominance refers to the effect of a heterozygous genotype relative to that of the two homozygous genotypes. The degree of dominance of mutations for fitness can have a profound impact on how deleterious and beneficial mutations change in frequency over time as well as on the patterns of linked neutral genetic variation surrounding such selected alleles. Since dominance is such a fundamental concept, it has received immense attention throughout the history of population genetics. Early work from Fisher, Wright, and Haldane focused on understanding the conceptual basis for why dominance exists. More recent work has attempted to test these theories and conceptual models by estimating dominance effects of mutations. However, estimating dominance coefficients has been notoriously challenging and has only been done in a few species in a limited number of studies. In this review, we first describe some of the early theoretical and conceptual models for understanding the mechanisms for the existence of dominance. Second, we discuss several approaches used to estimate dominance coefficients and summarize estimates of dominance coefficients. We note trends that have been observed across species, types of mutations, and functional categories of genes. By comparing estimates of dominance coefficients for different types of genes, we test several hypotheses for the existence of dominance. Lastly, we discuss how dominance influences the dynamics of beneficial and deleterious mutations in populations and how the degree of dominance of deleterious mutations influences the impact of inbreeding on fitness.
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  • 文章类型: Journal Article
    参观博物馆等非正规教育机会,水族馆,和动物园支持儿童的语义知识获得。大多数研究集中在直接学习的结果,比如事实召回。儿童通过记忆整合参与推理和自我推导等生产性记忆过程的程度尚未得到很好的理解。我们评估了8至9岁儿童在直接测试中的表现(例如,事实回忆)和生产性(例如,推断,集成)从虚拟博物馆展品中学习。我们还研究了儿童参与对学习成果的影响,通过测量展览内二元对话和展览后反射。孩子们在所有三项学习测试中都成功地完成了;事实回忆是最容易获得的,而自我推导是最少的。展览内和展览后的参与都可以预测整体学习成果;展览内的对话短语尤其可以预测自我派生表现。当前的工作为支持儿童非正式学习的机制提供了新的见解。
    Informal educational opportunities such as visits to museums, aquariums, and zoos support children\'s semantic knowledge gain. Most research focuses on outcomes of direct learning, such as factual recall. The extent to which children engage in productive memory processes such as inferential reasoning and self-derivation through memory integration is not yet well understood. We assessed 8- to 9-year-old children\'s performance on tests of direct (e.g., fact recall) and productive (e.g., inference, integration) learning from virtual museum exhibits. We also examined the influence of children\'s involvement on learning outcomes, through measuring within-exhibit dyadic conversation and post-exhibit reflection. Children performed successfully on all three tests of learning; fact recall was the most accessible and self-derivation was the least. Both within and post-exhibit involvement predicted overall learning outcomes; within-exhibit conversational phrases predicted self-derivation performance in particular. The current work provides novel insights into mechanisms that support children\'s informal learning.
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  • 文章类型: Journal Article
    边缘服务器经常管理自己的离线数字孪生(DT)服务,除了在线缓存数字孪生服务。然而,当前的研究往往忽视了离线缓存服务对内存和计算资源的影响,这可能会影响边缘服务器上在线服务任务的处理效率。在这项研究中,通过强调在线和离线边缘服务的集成服务质量(QoS),我们专注于协作边缘计算系统中的服务缓存和任务卸载。我们考虑了在线和离线服务的资源使用情况,以及传入的在线请求。为了最大化整体QoS效用,我们建立了一个优化目标,奖励在线服务的吞吐量,同时惩罚错过软期限的离线服务。我们将其表述为效用最大化问题,这被证明是NP-hard。为了解决这种复杂性,我们将优化问题重新定义为马尔可夫决策过程(MDP),并通过利用深度Q网络(DQN)引入了用于服务缓存和任务卸载的联合优化算法。综合实验表明,与基线算法相比,我们的算法将效用提高了至少14.01%。
    Edge servers frequently manage their own offline digital twin (DT) services, in addition to caching online digital twin services. However, current research often overlooks the impact of offline caching services on memory and computation resources, which can hinder the efficiency of online service task processing on edge servers. In this study, we concentrated on service caching and task offloading within a collaborative edge computing system by emphasizing the integrated quality of service (QoS) for both online and offline edge services. We considered the resource usage of both online and offline services, along with incoming online requests. To maximize the overall QoS utility, we established an optimization objective that rewards the throughput of online services while penalizing offline services that miss their soft deadlines. We formulated this as a utility maximization problem, which was proven to be NP-hard. To tackle this complexity, we reframed the optimization problem as a Markov decision process (MDP) and introduced a joint optimization algorithm for service caching and task offloading by leveraging the deep Q-network (DQN). Comprehensive experiments revealed that our algorithm enhanced the utility by at least 14.01% compared with the baseline algorithms.
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  • 文章类型: Journal Article
    测量遗传变异的适宜性是进化生物学的基本目标。大量测量微生物适合度的标准方法包括用独特的序列条形码标记遗传变异库。在分批培养中竞争标记的菌株,并使用深度测序来跟踪条形码丰度随时间的变化。然而,条形码的特殊性质可以诱导不均匀的扩增或不均匀的测序覆盖,这导致一些条形码在样品中被过高或过低地表示。这种系统偏差可能导致错误的读取计数轨迹和对适合度的错误估计。在这里,我们开发了一种计算方法,REBAR,通过利用数据中系统偏差的结构来推断条形码处理偏差的影响。我们通过将其应用于两个独立的数据集来说明这种方法,并证明该方法比标准代理更准确地估计和校正偏差,例如基于GC的校正。REBAR减轻了偏差并改善了高通量测定中的适应度估计,而不会给实验方案带来额外的复杂性。在一系列实验进化和突变筛选环境中具有潜在的应用。
    Measuring the fitnesses of genetic variants is a fundamental objective in evolutionary biology. A standard approach for measuring microbial fitnesses in bulk involves labeling a library of genetic variants with unique sequence barcodes, competing the labeled strains in batch culture, and using deep sequencing to track changes in the barcode abundances over time. However, idiosyncratic properties of barcodes can induce nonuniform amplification or uneven sequencing coverage that causes some barcodes to be over- or under-represented in samples. This systematic bias can result in erroneous read count trajectories and misestimates of fitness. Here, we develop a computational method, named REBAR (Removing the Effects of Bias through Analysis of Residuals), for inferring the effects of barcode processing bias by leveraging the structure of systematic deviations in the data. We illustrate this approach by applying it to two independent data sets, and demonstrate that this method estimates and corrects for bias more accurately than standard proxies, such as GC-based corrections. REBAR mitigates bias and improves fitness estimates in high-throughput assays without introducing additional complexity to the experimental protocols, with potential applications in a range of experimental evolution and mutation screening contexts.
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  • 文章类型: Journal Article
    模态是建模的重要课题。当真实数据集显示三模态时,使用参数模型是一种有效的方法。在本文中,我们提出了一类新的三峰概率分布,也就是说,具有多达三种模式的概率分布。三模态本身是通过对某些连续概率分布的密度函数应用适当的变换来实现的。起初,我们得到了任意密度函数g(x)和,接下来,我们专注于高斯的情况,对三模态高斯模型的研究更加深入。高斯分布用于产生称为正态分布的高斯三峰形式。正态分布解析表达式的可操作性和三峰正态分布的性质是我们选择正态分布的重要原因。此外,当数据集中存在三峰形式时,应该改进现有的分布,以便能够有效地建模。在提出新的密度函数后,估计其参数很重要。由于Mathematica12.0软件具有优化工具和重要的建模技术,使用该软件执行计算步骤。当实际数据集显示三模态时,实际数据集的自举形式用于显示所提出的分布的建模能力。
    The modality is an important topic for modelling. Using parametric models is an efficient way when real data set shows trimodality. In this paper, we propose a new class of trimodal probability distributions, that is, probability distributions that have up to three modes. Trimodality itself is achieved by applying a proper transformation to density function of certain continuous probability distributions. At first, we obtain preliminary results for an arbitrary density function g ( x ) and, next, we focus on the Gaussian case, studying trimodal Gaussian model more deeply. The Gaussian distribution is applied to produce the trimodal form of Gaussian known as normal distribution. The tractability of analytical expression of normal distribution and properties of the trimodal normal distribution are important reasons why we choose normal distribution. Furthermore, the existing distributions should be improved to be capable of modelling efficiently when there exists a trimodal form in a data set. After new density function is proposed, estimating its parameters is important. Since Mathematica 12.0 software has optimization tools and important modelling techniques, computational steps are performed using this software. The bootstrapped form of real data sets are applied to show the modelling ability of the proposed distribution when real data sets show trimodality.
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  • 文章类型: Journal Article
    病毒对微生物种群的影响取决于相互作用表型,包括跨越吸附率的病毒性状,潜伏期,和突发大小。潜伏期是裂解感染的关键病毒性状。DefiNed为从病毒吸附到病毒后代释放的时间,噬菌体的潜伏期通常是通过一步生长曲线推断的,其中随着时间的推移,游离病毒在感染细胞群中的积累。发展于80多年前,一步生长曲线不考虑裂解时间的细胞水平变化,病毒性状的潜在偏倚推断。这里,我们使用非线性动力学模型来了解潜伏期的个体水平变化如何影响病毒-宿主动力学。我们的建模方法表明,通过一步增长曲线推断潜伏期是系统有偏差的,从而产生了比基础人口水平平均值更短的潜伏期的估计值。产生偏差是因为细胞水平的裂解时间的可变性导致一部分早期爆发事件。被解释,事实上,作为病毒释放的较早平均时间。我们开发了一个计算框架,通过对宿主和游离病毒种群的联合测量来估计潜伏期变异性。我们的计算框架可以恢复模拟感染中潜伏期的均值和方差,包括现实的测量噪声。这项工作表明,将潜伏期重新定义为一种分布以解释种群的变异性将改善对病毒性状及其在塑造微生物种群中的作用的研究。重要定量病毒性状-包括吸附率,突发大小,和潜伏期-对于表征病毒感染动力学和开发从细胞到生态系统跨尺度的病毒影响的预测模型至关重要。这里,我们重新审视了病毒性状估计的金标准-一步生长曲线-以评估病毒感染动力学核心假设在多大程度上导致病毒性状推断的持续和系统偏差.我们表明,通过一步增长曲线获得的潜伏期估计系统地低估了平均潜伏期,反过来,高估了人口规模的病毒杀伤率。通过明确地将特征变异性纳入利用病毒和宿主时间序列的动态推理框架,我们提供了一条实用的途径来改善对不同病毒-微生物系统中病毒性状的均值和方差的估计.
    Viral impacts on microbial populations depend on interaction phenotypes-including viral traits spanning the adsorption rate, latent period, and burst size. The latent period is a key viral trait in lytic infections. Defined as the time from viral adsorption to viral progeny release, the latent period of bacteriophage is conventionally inferred via one-step growth curves in which the accumulation of free virus is measured over time in a population of infected cells. Developed more than 80 years ago, one-step growth curves do not account for cellular-level variability in the timing of lysis, potentially biasing inference of viral traits. Here, we use nonlinear dynamical models to understand how individual-level variation of the latent period impacts virus-host dynamics. Our modeling approach shows that inference of the latent period via one-step growth curves is systematically biased-generating estimates of shorter latent periods than the underlying population-level mean. The bias arises because variability in lysis timing at the cellular level leads to a fraction of early burst events, which are interpreted, artefactually, as an earlier mean time of viral release. We develop a computational framework to estimate latent period variability from joint measurements of host and free virus populations. Our computational framework recovers both the mean and variance of the latent period within simulated infections including realistic measurement noise. This work suggests that reframing the latent period as a distribution to account for variability in the population will improve the study of viral traits and their role in shaping microbial populations.IMPORTANCEQuantifying viral traits-including the adsorption rate, burst size, and latent period-is critical to characterize viral infection dynamics and develop predictive models of viral impacts across scales from cells to ecosystems. Here, we revisit the gold standard of viral trait estimation-the one-step growth curve-to assess the extent to which assumptions at the core of viral infection dynamics lead to ongoing and systematic biases in inferences of viral traits. We show that latent period estimates obtained via one-step growth curves systematically underestimate the mean latent period and, in turn, overestimate the rate of viral killing at population scales. By explicitly incorporating trait variability into a dynamical inference framework that leverages both virus and host time series, we provide a practical route to improve estimates of the mean and variance of viral traits across diverse virus-microbe systems.
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  • 文章类型: Journal Article
    目的:基因调控网络(GRN)推断是生物学和医学中的一项基本任务,因为它可以更深入地了解生物中基因表达的复杂机制。该生物信息学问题已通过多种计算方法在文献中得到解决。为从表达数据推断而开发的技术采用了贝叶斯网络,常微分方程(ODE),机器学习,信息论测度和神经网络,在其他人中。实现方式的多样性及其各自的定制化,导致了许多工具的出现以及由此衍生的多个专门领域,被理解为具有特定特征的网络子集,这些特征在先验检测方面具有挑战性。在为特定数据集选择最合适的技术时,这种专业化引入了显着的不确定性。这个提议,名为MO-GENECI,建立在先前提议GENECI的基本思想之上,并优化了不同推理技术之间的共识,通过以各种目标函数为指导的精心完善的多目标进化算法,与手头的生物环境有关。
    方法:MO-GENECI已在广泛而多样的学术基准上进行了测试,该基准包括来自多个来源和规模的106个基因调控网络。MO-GENECI的评估将其性能与使用关键指标(AUROC和AUPR)进行基因调控网络推断的单个技术进行了比较。弗里德曼的统计排名提供了有序的分类,然后进行非参数Holm检验以确定统计学意义。
    结果:MO-GENECI\的Pareto前沿近似有助于根据通用输入数据特征轻松选择合适的解决方案。在所有统计测试中,最佳解决方案始终是赢家,在很多情况下,中位数精度解决方案与获胜者相比无统计学差异.
    结论:MO-GENECI不仅证明了比单个技术获得更准确的结果,但由于其灵活性和适应性,也克服了与初始选择相关的不确定性。显示了为每种情况智能地选择最合适的技术。源代码托管在GitHub的公共存储库中,并获得MIT许可:https://github.com/AdrianSeguraOrtiz/MO-GENECI。此外,为了方便其安装和使用,与此实现相关的软件已封装在PyPI:https://pypi.org/project/geneci/上的Python包中。
    OBJECTIVE: Gene Regulatory Network (GRN) inference is a fundamental task in biology and medicine, as it enables a deeper understanding of the intricate mechanisms of gene expression present in organisms. This bioinformatics problem has been addressed in the literature through multiple computational approaches. Techniques developed for inferring from expression data have employed Bayesian networks, ordinary differential equations (ODEs), machine learning, information theory measures and neural networks, among others. The diversity of implementations and their respective customization have led to the emergence of many tools and multiple specialized domains derived from them, understood as subsets of networks with specific characteristics that are challenging to detect a priori. This specialization has introduced significant uncertainty when choosing the most appropriate technique for a particular dataset. This proposal, named MO-GENECI, builds upon the basic idea of the previous proposal GENECI and optimizes consensus among different inference techniques, through a carefully refined multi-objective evolutionary algorithm guided by various objective functions, linked to the biological context at hand.
    METHODS: MO-GENECI has been tested on an extensive and diverse academic benchmark of 106 gene regulatory networks from multiple sources and sizes. The evaluation of MO-GENECI compared its performance to individual techniques using key metrics (AUROC and AUPR) for gene regulatory network inference. Friedman\'s statistical ranking provided an ordered classification, followed by non-parametric Holm tests to determine statistical significance.
    RESULTS: MO-GENECI\'s Pareto front approximation facilitates easy selection of an appropriate solution based on generic input data characteristics. The best solution consistently emerged as the winner in all statistical tests, and in many cases, the median precision solution showed no statistically significant difference compared to the winner.
    CONCLUSIONS: MO-GENECI has not only demonstrated achieving more accurate results than individual techniques, but has also overcome the uncertainty associated with the initial choice due to its flexibility and adaptability. It is shown intelligently to select the most suitable techniques for each case. The source code is hosted in a public repository at GitHub under MIT license: https://github.com/AdrianSeguraOrtiz/MO-GENECI. Moreover, to facilitate its installation and use, the software associated with this implementation has been encapsulated in a Python package available at PyPI: https://pypi.org/project/geneci/.
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