parallelism

并行性
  • 文章类型: Journal Article
    背景:系统发育在生物学研究中起着至关重要的作用。不幸的是,寻找最优的系统发育树带来了巨大的计算成本,大多数现有的最先进的工具无法在合理的时间内处理非常大的数据集。
    结果:在这项工作中,我们介绍了新的VeryFastTree代码(版本4.0),它能够在一台服务器上使用单精度算法在36小时内从一个庞大的100万个对齐数据集中构建一棵树,分别比以前的版本和FastTree-2快3倍和3.2倍。这个新版本通过在树构建过程中并行化所有树遍历操作,进一步提高了性能。包括子树修剪和回归动作。此外,它引入了重要的新功能,例如支持新的和压缩的文件格式,在更广泛的操作系统中增强兼容性,以及磁盘计算功能的集成。后一个特征对于没有访问高端服务器的用户特别有利,因为它允许他们管理非常大的数据集,尽管计算时间增加了。
    结论:实验结果证明VeryFastTree是最先进的最大似然系统发育估计工具中最快的工具。它可以在https://github.com/citiususec/veryfasttree上公开获得。此外,VeryFastTree作为包包含在Bioconda中,MacPorts,和所有基于Debian的Linux发行版。
    BACKGROUND: Phylogenies play a crucial role in biological research. Unfortunately, the search for the optimal phylogenetic tree incurs significant computational costs, and most of the existing state-of-the-art tools cannot deal with extremely large datasets in reasonable times.
    RESULTS: In this work, we introduce the new VeryFastTree code (version 4.0), which is able to construct a tree on 1 server using single-precision arithmetic from a massive 1 million alignment dataset in only 36 hours, which is 3 times and 3.2 times faster than its previous version and FastTree-2, respectively. This new version further boosts performance by parallelizing all tree traversal operations during the tree construction process, including subtree pruning and regrafting moves. Additionally, it introduces significant new features such as support for new and compressed file formats, enhanced compatibility across a broader range of operating systems, and the integration of disk computing functionality. The latter feature is particularly advantageous for users without access to high-end servers, as it allows them to manage very large datasets, albeit with an increase in computing time.
    CONCLUSIONS: Experimental results establish VeryFastTree as the fastest tool in the state-of-the-art for maximum likelihood phylogeny estimation. It is publicly available at https://github.com/citiususc/veryfasttree. In addition, VeryFastTree is included as a package in Bioconda, MacPorts, and all Debian-based Linux distributions.
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  • 文章类型: Journal Article
    对表型进化的限制可以导致趋同进化的模式,通过限制面对内源性(功能性,发展)或外生(竞争,捕食)选择性压力。对收敛性的评估取决于将生态和形态数据整合到一个稳健的、比较系统发育背景。硬骨鱼的惊人多样性提供了许多适应类似生态角色的谱系,因此,提供了许多重复的进化实验来探索表型趋同。然而,我们对鱼类喂养系统的理解主要是由海洋物种形成的,除了淡水丽鱼科鱼。在这里,我们使用食人鱼和pacus(Serrasalmidae)来探索新热带淡水环境中不同摄食生态及其形态代理的演变。具体来说,我们探讨了以植物为食的鱼类之间的融合是否更为普遍,源于对食草动物表型进化的强烈限制。使用骨学显微计算机断层扫描成像(μCT),我们描述了pacus和piranhas的形态变异的主轴,关于他们的饮食和喂养行为。接下来,我们评估了草食性生态位是否比其他饮食行会更不稳定,以及草食性物种的表型是否比其他分类群进化速度更慢。然后,我们评估草食类群的趋同程度,使用三种不同的形态特征套件(牙齿,下巴,和腹部形态计量学)。生态学上,食草动物不是死胡同,表现出与食肉动物和杂食动物之间相似的观察到的过渡率。然而,我们记录了食草动物的广泛趋同,食草动物的表型进化速度比食肉动物慢。大多数趋同的例子都是在食草类群中发现的,特别是在食肉动物和树叶中。此外,\'完全\'收敛的实例,在多个形态测量数据集中观察到的正收敛度量表明,只在食草动物中发现。食草动物似乎在受限的情况下进化,但这并没有限制他们的生态不稳定。
    Constraints on phenotypic evolution can lead to patterns of convergent evolution, by limiting the \'pool\' of potential phenotypes in the face of endogenous (functional, developmental) or exogenous (competition, predation) selective pressures. Evaluation of convergence depends on integrating ecological and morphological data within a robust, comparative phylogenetic context. The staggering diversity of teleost fishes offers a multitude of lineages adapted for similar ecological roles, and therefore, offers numerous replicated evolutionary experiments for exploring phenotypic convergence. However, our understanding of fish feeding systems has been primarily shaped by marine species, with the monolithic exception of freshwater cichlids. Here we use piranhas and pacus (Serrasalmidae) to explore the evolution of different feeding ecologies and their morphological proxies in Neotropical freshwater environments. Specifically, we explore whether convergence is more widespread among plant-eating fishes, arising from strong constraints on phenotypic evolution in herbivores. Using osteological micro-computed tomographic imaging (μCT), we describe the major axes of morphological variation in pacus and piranhas, regarding their diet and feeding behaviors. Next, we evaluated whether herbivorous niches are less labile than other dietary guilds and whether herbivorous species\' phenotypes evolve at a slower evolutionary rate than other taxa. We then assess how convergent herbivorous taxa are, using three different suites of morphological characters (dental, jaw, and abdominal morphometrics). Ecologically, herbivory is not a dead end, exhibiting similar observed transition rates as those between carnivores and omnivores. However, we documented widespread convergence in herbivores and that herbivores have slower rates of phenotypic evolution than carnivores. Most instances of convergence are found in herbivorous taxa, specifically in frugivores and folivores. Moreover, instances of \'complete\' convergence, indicated by positive convergence metrics observed in more than one morphometric dataset, were only found in herbivores. Herbivores do appear to evolve under constrained circumstances, but this has not limited their ecological lability.
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  • 文章类型: Journal Article
    介绍全膝关节置换术的目标是用人工植入物替代患病的软骨和骨骼,以改善患者的生活质量。从历史上看,膝关节已根据患者的机械轴(MA)进行了重建。然而,运动学对齐技术已被越来越多地使用。运动学对齐需要较少的软组织切除,并将膝盖与患者解剖学上自然的对齐,同时,人们担心,由于植入物上潜在的重量分布不均,运动学对齐的膝盖会导致较早的失败。这项研究的目的是使用运动学和机械对准比较关节线切口的平行度,并了解MA是否是胫骨-踝轴(TA)的正确估计。方法采用回顾性研究方法,招募2013年1月至2020年7月2日在两家MedStarHealth医院接受两名外科医生手术的胫骨高位截骨和股骨远端截骨受者,为修复手术做准备。使用Kellgren-Lawrence分类系统对基线骨关节炎进行分级,所有患者均为0级。在66条腿上测量了TA和MA的关节线方向以及运动轴(KA)。使用配对t检验在MA和KA之间以及在MA和TA之间比较从平行度到地面的平均距离。结果KA关节线取向(1.705°偏差)在双足站立阶段比MA更平行于地板(2.316°偏差,p=0.0156)。MA(2.316°偏差)不是TA的正确估计(4.278°偏差,p=0.0001)。结论利用KA技术,自然关节线的恢复,以及与MA相比,在站立阶段更平行于地板的关节,已实现。在双足站立阶段,KA与地面的平行度表明膝盖上的载荷分布均匀。此外,由于它与KA的相似性和承重分布的解剖学意义,需要进一步研究髋至跟骨轴作为关节线的近似值.
    Introduction The goal of total knee arthroplasty is to replace diseased cartilage and bone with an artificial implant to improve the patient\'s quality of life. The knee has historically been reconstructed to the patient\'s mechanical axis (MA). However, kinematically aligned techniques have been increasingly used. Kinematic alignment requires less soft-tissue resection and aligns the knee with what is anatomically natural to the patient, while there is concern that kinematically aligned knees will lead to earlier failure due to potential unequal weight distribution on the implant. The purpose of this study is to compare the parallelism from the floor of the joint-line cuts using kinematic and mechanical alignment and understand if the MA is a proper estimation of the tibial-ankle axis (TA). Methods A retrospective study was conducted by recruiting all high tibial osteotomy and distal femoral osteotomy recipients operated on by two surgeons in two MedStar Health hospitals from 01/2013 to 07/2020 with full-length films in preparation for restorative procedures. Baseline osteoarthritis was graded using the Kellgren-Lawrence classification system with all patients presenting as Grade 0. The TA and the joint-line orientations of the MA and kinematic axis (KA) were measured on 66 legs. The average distance from parallelism to the ground was compared between the MA and the KA and between the MA and the TA using a paired t-test. Results KA joint-line orientation (1.705° deviation) was more parallel to the floor in the bipedal stance phase than the MA (2.316° deviation, p=0.0156). The MA (2.316° deviation) was not a proper estimation of the TA (4.278° deviation, p=0.0001). Conclusion By utilizing the KA technique, the restoration of the natural joint line, as well as a joint that is more parallel to the floor in the stance phase compared to the MA, is achieved. The parallelism to the ground of the KA during the bipedal stance phase suggests an even load distribution across the knee. In addition, due to its similarity to the KA and anatomical significance in weight-bearing distribution, further investigation into the hip-to-calcaneal axis as an approximation of the joint line is warranted.
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  • 文章类型: Journal Article
    图形处理单元(GPU)促进大规模并行性和高容量存储,因此适用于使用有序子集期望最大化(OSEM)通过实时系统矩阵(OTFSM)计算来迭代重建超高分辨率微型计算机断层扫描(CT)扫描。我们提出了一种有限状态自动机(FSA)方法,该方法通过对从有序子集的射线跟踪系统得出的矩阵计算进行并行化,从而使用异构多GPU平台促进迭代重建。FSA对异构GPU的并行线程执行流控制,它最大限度地减少了启动有序子集任务的延迟,减少了主系统内存和本地GPU内存之间的数据传输,并解决单个GPU的内存限制。在实验中,我们比较了OS-MLTR在三种重建环境下的运行效率。具有作业队列的异构多GPU实现高吞吐量计算速度,比单GPU环境快五倍,并且该速度比具有设备调度控制的FIFO队列的异构多个GPU快九倍。最终,我们提出了一种事件触发的FSA方法,用于使用多个异构GPU进行迭代重建,解决了单个GPU在超高分辨率下的内存限制问题,并且所提出方法的例程在每个GPU上同时成功执行。
    Graphics processing units (GPUs) facilitate massive parallelism and high-capacity storage, and thus are suitable for the iterative reconstruction of ultrahigh-resolution micro computed tomography (CT) scans by on-the-fly system matrix (OTFSM) calculation using ordered subsets expectation maximization (OSEM). We propose a finite state automaton (FSA) method that facilitates iterative reconstruction using a heterogeneous multi-GPU platform through parallelizing the matrix calculations derived from a ray tracing system of ordered subsets. The FSAs perform flow control for parallel threading of the heterogeneous GPUs, which minimizes the latency of launching ordered-subsets tasks, reduces the data transfer between the main system memory and local GPU memory, and solves the memory-bound of a single GPU. In the experiments, we compared the operation efficiency of OS-MLTR for three reconstruction environments. The heterogeneous multiple GPUs with job queues for high throughput calculation speed is up to five times faster than the single GPU environment, and that speed up is nine times faster than the heterogeneous multiple GPUs with the FIFO queues of the device scheduling control. Eventually, we proposed an event-triggered FSA method for iterative reconstruction using multiple heterogeneous GPUs that solves the memory-bound issue of a single GPU at ultrahigh resolutions, and the routines of the proposed method were successfully executed on each GPU simultaneously.
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  • 文章类型: Journal Article
    糖尿病肾病(DN)和糖尿病视网膜病变(DR),作为糖尿病的微血管并发症,目前是终末期肾病(ESRD)和失明的主要原因,分别,在成年劳动人口中,它们是具有社会和经济负担的重大公共卫生问题。两者在发生发展过程中的平行性表现为致病危险因素和发病机制的高度重叠,高合并症发生率,相互预测的效果,和临床用药的部分一致性。然而,因为这两个器官,眼睛和肾脏,有其独特的内部环境和生理过程,每个都有特定的影响分子,由于不同的病理改变和对各种影响因素的反应,靶器官具有非平行性,本文对DN和DR的平行性和不平行性进行了概述,以进一步认识两种疾病的共同点和区别,为早期诊断提供参考。使用药物的临床指导,以及新药的开发。
    Diabetic nephropathy (DN) and diabetic retinopathy (DR), as microvascular complications of diabetes mellitus, are currently the leading causes of end-stage renal disease (ESRD) and blindness, respectively, in the adult working population, and they are major public health problems with social and economic burdens. The parallelism between the two in the process of occurrence and development manifests in the high overlap of disease-causing risk factors and pathogenesis, high rates of comorbidity, mutually predictive effects, and partial concordance in the clinical use of medications. However, since the two organs, the eye and the kidney, have their unique internal environment and physiological processes, each with specific influencing molecules, and the target organs have non-parallelism due to different pathological changes and responses to various influencing factors, this article provides an overview of the parallelism and non-parallelism between DN and DR to further recognize the commonalities and differences between the two diseases and provide references for early diagnosis, clinical guidance on the use of medication, and the development of new drugs.
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  • 文章类型: Journal Article
    为了满足列车速度和高速空气动力学测试对轨道几何参数检测设备的需求,设计了具有对中极限的零位校准仪表装置,高度调整和水平显示功能。分析了零位校规的弯曲情况,研究了加工工艺,保证了零位校规设计的合理性和可实现性。然后,对零校准量规的零值和工作表面的平行度进行了实验测试。实验结果表明,量规零值参数为1434.829mm,标准偏差为1.4μm。两个上工作面的平行度为1.1μm,两个内工作表面的平行度为4μm。最后,完成了零点校准仪的不确定度评定。量规零值的测量不确定度为12μm,高度差的测量不确定度为6μm。
    To meet the demand for the track\'s geometric parameter detection equipment for train speed and high-speed aerodynamics tests, a zero-calibration gauge device is designed with the centering limit, height adjustment and horizontal display function in this paper. The bending situation of the zero-calibration gauge is analyzed and the processing technology is studied, which ensures the rationality and realizability of the design of zero-calibration gauge. Then the gauge zero value and the parallelism of the working surface of zero-calibration gauge have been experimentally tested. The experimental results show that the parameter of gauge zero value is 1434.829 mm with a standard deviation of 1.4 μm. The parallelism of the two upper working surfaces is 1.1 μm, and the parallelism of the two inner working surfaces is 4 μm. Finally, the uncertainty evaluation of zero-calibration gauge is completed. The measurement uncertainty of gauge zero value is 12 μm and the measurement uncertainty of height difference is 6 μm.
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  • 文章类型: Journal Article
    诗词通常涉及两类互补的特征:(I)并行性,即重复模式(押韵,米,头韵,等。)增强即将到来的单词的可预测性,和(ii)诗歌偏差,挑战有关常规单词形式和顺序的标准期望/预测。本研究调查了这两种预测调节诗词的基本原理如何影响诗歌的认知加工和审美评价,幽默的对联和谚语。我们开发了这两组文本特征的定量度量。在三种文本类型中,较高的偏差分数降低了可理解性和审美喜好,而较高的平行性分数增强了这些。平行性的积极影响明显强于偏差特征的同时负面影响。这些结果符合以下假设:艺术接收涉及预测误差和预测误差最小化的相互作用,后者为加工流畅性和审美情趣铺平了道路。这篇文章是主题问题的一部分\'艺术,美学与预测加工:理论与实证视角。
    Poetic diction routinely involves two complementary classes of features: (i) parallelisms, i.e. repetitive patterns (rhyme, metre, alliteration, etc.) that enhance the predictability of upcoming words, and (ii) poetic deviations that challenge standard expectations/predictions regarding regular word form and order. The present study investigated how these two prediction-modulating fundamentals of poetic diction affect the cognitive processing and aesthetic evaluation of poems, humoristic couplets and proverbs. We developed quantitative measures of these two groups of text features. Across the three text genres, higher deviation scores reduced both comprehensibility and aesthetic liking whereas higher parallelism scores enhanced these. The positive effects of parallelism are significantly stronger than the concurrent negative effects of the features of deviation. These results are in accord with the hypothesis that art reception involves an interplay of prediction errors and prediction error minimization, with the latter paving the way for processing fluency and aesthetic liking. This article is part of the theme issue \'Art, aesthetics and predictive processing: theoretical and empirical perspectives\'.
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  • 文章类型: Preprint
    跨环境梯度的平行跃迁可以是适应的有力证据。家鼠(Musmusculusdomesticus)是由欧洲殖民者引入美洲的,现在从火地岛到阿拉斯加广泛分布。气候的多个方面,如温度,在美洲,不同的纬度是可以预见的。过去对北美人群跨纬度梯度的研究提供了与体型相关的特征的环境适应性的证据,新陈代谢,和行为,并使用选择扫描确定候选基因。这里,我们研究了第二个大陆上环境适应的基因组信号,南美洲,并询问是否有证据表明在美洲的多个纬度样例之间存在平行适应。我们首先在整个基因组中确定了基因座,这些基因座显示了与南美纬度样区采样的小鼠的气候变化相关的选择特征,考虑中性人口结构。与以前的结果一致,大多数候选SNP位于调控区.包含最极端异常值的基因与体重或大小等特征有关,新陈代谢,豁免权,脂肪,和眼睛的发育或功能以及与心血管和肾脏系统相关的特征。然后,我们将这些结果与北美两个横断面的已发表结果相结合。虽然大多数候选基因是个体样片所独有的,我们发现在三个样片中独立鉴定的候选基因之间存在显著重叠,提供平行适应的有力证据,并确定可能是北美和南美家鼠最近环境适应的基础的基因。
    自从他们与欧洲殖民者一同抵达,家鼠已经成功地传播到整个美洲。有强有力的证据表明,当时北美的人口已经适应了,包括跨纬度的表型平行进化(例如,身体尺寸,行为)以及对显示选择信号的基因的识别。这里,我们调查了南美洲环境适应的遗传学。我们发现,南美洲的人口独立于北美洲的人口发展。我们确定了与体型等特征有关的环境适应候选基因,新陈代谢,豁免权,眼睛功能,以及心血管和肾脏系统。然后,我们汇集了来自两大洲三个横断面的数据,以确定环境适应是否可预测,响应共同条件的平行遗传变化。我们发现,环境适应的大多数证据都存在于监管区域,虽然大多数候选基因是个体样片所独有的,许多是共享的,提供平行适应的重要证据。我们确定了在所有三个样带中独立识别的候选基因的核心集,这些基因可能有助于美洲的环境适应。这些结果突出了研究该遗传模型系统的野生种群的价值。
    Parallel clines across environmental gradients can be strong evidence of adaptation. House mice (Mus musculus domesticus) were introduced to the Americas by European colonizers and are now widely distributed from Tierra del Fuego to Alaska. Multiple aspects of climate, such as temperature, vary predictably across latitude in the Americas. Past studies of North American populations across latitudinal gradients provided evidence of environmental adaptation in traits related to body size, metabolism, and behavior and identified candidate genes using selection scans. Here, we investigate genomic signals of environmental adaptation on a second continent, South America, and ask whether there is evidence of parallel adaptation across multiple latitudinal transects in the Americas. We first identified loci across the genome showing signatures of selection related to climatic variation in mice sampled across a latitudinal transect in South America, accounting for neutral population structure. Consistent with previous results, most candidate SNPs were in regulatory regions. Genes containing the most extreme outliers relate to traits such as body weight or size, metabolism, immunity, fat, and development or function of the eye as well as traits associated with the cardiovascular and renal systems. We then combined these results with published results from two transects in North America. While most candidate genes were unique to individual transects, we found significant overlap among candidate genes identified independently in the three transects, providing strong evidence of parallel adaptation and identifying genes that likely underlie recent environmental adaptation in house mice across North and South America.
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  • 文章类型: Review
    背景:研究授粉综合征的一般观点是,花卉性状通常代表对特定功能性传粉者群体的会聚花卉适应。然而,融合的定义在文献中是难以捉摸和矛盾的。融合是相同性状或具有相同功能的相似性状的独立进化吗?对发育生物学和系统发育系统学中的融合概念的回顾可能会为授粉综合征的研究提供新的思路。
    方法:本文的目的:(i)探讨趋同的概念和其他概念(类比,同质,和平行性)在发育进化和系统发育系统学的理论和实践中;(ii)修改综合症的定义,以拥抱类比和趋同的概念;(iii)在被子植物系统发育的背景下重新审视蝙蝠授粉综合症,重点关注与该综合征相关的艳丽的“花瓣状”器官;(iv)重新审视花朵颜色的遗传发育基础;(v)提出与蝙蝠授粉综合征相关的花卉进化的进化假设;(vi)强调有关花的起源和进化及其对21世纪授粉综合征研究的影响的当前研究前沿。
    结论:将类比和趋同的概念纳入综合症的概念将构成一个新的研究议程,该议程将整合花卉生物学,系统发育系统学,和发育生物学。eudicots和单子叶植物的叶状和翼足蝙蝠授粉综合征特征代表了类似和趋同进化的情况。授粉综合征是一个多变量概念,本质上与对花器官发生和进化的理解有关。授粉综合征假设的制定必须考虑植物和动物类群普遍性的系统发育水平,花的发育,遗传学,同源性,和进化,以及对进化概念的明确定义,包括类比,收敛,同质,和并行性。
    A general view in the study of pollination syndromes is that floral traits usually represent convergent floral adaptations to specific functional pollinator groups. However, the definition of convergence is elusive and contradictory in the literature. Is convergence the independent evolution of either the same trait or similar traits with the same function? A review of the concept of convergence in developmental biology and phylogenetic systematics may shed new light in studies of pollination syndromes.
    The aims of this article are (1) to explore the notion of convergence and other concepts (analogy, homoplasy and parallelism) within the theory and practice of developmental evolution and phylogenetic systematics; (2) to modify the definitions of syndromes in order to embrace the concepts of analogy and convergence; (3) to revisit the bat pollination syndrome in the context of angiosperm phylogeny, with focus on the showy \'petaloid\' organs associated with the syndrome; (4) to revisit the genetic-developmental basis of flower colour; (5) to raise evolutionary hypotheses of floral evolution associated with the bat pollination syndrome; and (6) to highlight some of the current frontiers of research on the origin and evolution of flowers and its impact on pollination syndrome studies in the 21st century.
    The inclusion of the concepts of analogy and convergence within the concept of syndromes will constitute a new agenda of inquiry that integrates floral biology, phylogenetic systematics and developmental biology. Phyllostomid and pteropodid bat pollination syndrome traits in eudicots and monocots represent cases of analogous and convergent evolution. Pollination syndromes are a multivariate concept intrinsically related to the understanding of flower organogenesis and evolution. The formulation of hypotheses of pollination syndromes must consider the phylogenetic levels of universality for both plant and animal taxa, flower development, genetics, homology and evolution, and a clear definition of evolutionary concepts, including analogy, convergence, homoplasy and parallelism.
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