inversion

倒置
  • 文章类型: Journal Article
    配备成像光谱辐射计的即将到来的地球观测卫星任务将很快提供前所未有的光谱数据流。该数据流将为量化生化和结构植被特性的多样性提供大量机会。如此大的数据流的处理要求需要可靠的检索技术,从而能够对生物物理变量进行时空显式量化。为了为地球观测的新时代做准备,这篇综述总结了用于推断各种植被生物物理变量的实验成像光谱学研究的最先进的检索方法。确定的检索方法分为:(1)参数回归,包括植被指数,形状指数和光谱变换;(2)非参数回归,包括线性和非线性机器学习回归算法;(3)基于物理,包括使用数值优化和查找表方法反演辐射传输模型(RTM);和(4)混合回归方法,将RTM仿真与机器学习回归方法相结合。对于每个类别,概述了广泛应用的方法,并应用于绘制植被属性。鉴于成像光谱数据的处理,一个关键方面涉及处理光谱多重共线性的挑战。提供稳健估计的能力,检索不确定性和可接受的检索处理速度是其他重要方面的考虑操作处理。给出了针对新一代基于光谱学的处理链的建议,这些链用于生物物理变量的运营生产。
    An unprecedented spectroscopic data stream will soon become available with forthcoming Earth-observing satellite missions equipped with imaging spectroradiometers. This data stream will open up a vast array of opportunities to quantify a diversity of biochemical and structural vegetation properties. The processing requirements for such large data streams require reliable retrieval techniques enabling the spatiotemporally explicit quantification of biophysical variables. With the aim of preparing for this new era of Earth observation, this review summarizes the state-of-the-art retrieval methods that have been applied in experimental imaging spectroscopy studies inferring all kinds of vegetation biophysical variables. Identified retrieval methods are categorized into: (1) parametric regression, including vegetation indices, shape indices and spectral transformations; (2) nonparametric regression, including linear and nonlinear machine learning regression algorithms; (3) physically based, including inversion of radiative transfer models (RTMs) using numerical optimization and look-up table approaches; and (4) hybrid regression methods, which combine RTM simulations with machine learning regression methods. For each of these categories, an overview of widely applied methods with application to mapping vegetation properties is given. In view of processing imaging spectroscopy data, a critical aspect involves the challenge of dealing with spectral multicollinearity. The ability to provide robust estimates, retrieval uncertainties and acceptable retrieval processing speed are other important aspects in view of operational processing. Recommendations towards new-generation spectroscopy-based processing chains for operational production of biophysical variables are given.
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  • 文章类型: Journal Article
    移除已植入很长时间的自扩张食管金属支架可能是困难且有风险的。
    在本文中,我们描述了在透视下使用"倒置技术"移除长期放置的自膨式镍钛诺食管支架,并评估了该方法的有效性和安全性.
    回顾性分析在我们中心透视下通过倒置技术移除自膨胀镍钛诺食管支架的患者。人口特征,食管支架类型,支架保留时间,移除支架的原因,从病例记录中收集并分析相关并发症。
    从纳入研究的107例患者中提取了总共112个金属食管支架(62个完全覆盖的食管支架和50个部分覆盖的食管支架)。支架植入术的适应症为恶性食管狭窄(27例),良性食管狭窄(42例),和食管瘘(38例)。支架保留的中位持续时间为77天(29-727天)。所有支架均成功取出,无食管破裂等严重并发症,大出血,窒息,或者心肺停止。
    透视下的反转技术似乎是一种安全的,有效,以及长期放置后去除自膨胀镍钛诺食管支架的快速程序。
    Removal of self-expanding esophageal metal stents that have been implanted for a long time can be difficult and risky.
    In this paper, we describe the use of the \"inversion technique\" under fluoroscopy for removal of self-expandable nitinol esophageal stents that have been placed for long periods and evaluate the effectiveness and safety of the method.
    Retrospective analysis of patients who underwent removal of self-expanding nitinol esophageal stents by the inversion technique under fluoroscopy at our center. Demographic characteristics, type of esophageal stents, stent retention time, reasons for stent removal, and related complications were collected from the case records and analyzed.
    A total of 112 metal esophageal stents (62 fully covered esophageal stents and 50 partially covered esophageal stents) were extracted from the 107 patients included in the study. Indications for stent implantation were malignant esophageal stenosis (27 patients), benign esophageal stenosis (42 patients), and esophageal fistula (38 patients). Median duration of stent retention was 77 days (29-727 days). All stents were removed successfully without major complications such as esophageal rupture, massive hemorrhage, asphyxia, or cardiorespiratory arrest.
    Inversion technique under fluoroscopy appears to be a safe, effective, and quick procedure for removal of self-expanding nitinol esophageal stent after long-term placement.
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  • 文章类型: Journal Article
    本文综述了粒子群算法在地球物理数据随机逆建模中的应用。总结了粒子群算法的主要特点,并分析了几个地球物理领域中最重要的贡献。目的是指出PSO方法发展的基本步骤,这些方法已被用来对地球的地下进行建模,然后对其益处和局限性进行严格评估。从现有的地球物理文献中选择了原始作品,以说明成功的PSO应用于电磁(大地电磁和时域)数据的解释,重力和磁性数据,自我潜能,直流电和地震数据。这些案例研究进行了严格的描述和比较。此外,提出了通过多目标PSO对多个地球物理数据集进行联合优化的方法,以突出使用单个求解器部署帕累托最优性来处理不同数据集而没有冲突解决方案的优势。最后,我们提出了从头开始实现自定义算法的最佳实践,以对任何类型的地球物理数据集进行随机逆建模,以使PSO从业人员或经验不足的研究人员受益。
    This paper reviews the application of the algorithm particle swarm optimization (PSO) to perform stochastic inverse modeling of geophysical data. The main features of PSO are summarized, and the most important contributions in several geophysical fields are analyzed. The aim is to indicate the fundamental steps of the evolution of PSO methodologies that have been adopted to model the Earth\'s subsurface and then to undertake a critical evaluation of their benefits and limitations. Original works have been selected from the existing geophysical literature to illustrate successful PSO applied to the interpretation of electromagnetic (magnetotelluric and time-domain) data, gravimetric and magnetic data, self-potential, direct current and seismic data. These case studies are critically described and compared. In addition, joint optimization of multiple geophysical data sets by means of multi-objective PSO is presented to highlight the advantage of using a single solver that deploys Pareto optimality to handle different data sets without conflicting solutions. Finally, we propose best practices for the implementation of a customized algorithm from scratch to perform stochastic inverse modeling of any kind of geophysical data sets for the benefit of PSO practitioners or inexperienced researchers.
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  • 文章类型: Journal Article
    电特性断层成像(EPT)是一种成像方法,它使用磁共振(MR)系统来非侵入性地确定被成像物体的电导率和介电常数的空间分布。这份手稿首先提供了关于所需数据的明确定义,并在,EPT,然后全面制定了大量分析EPT技术基础的物理方程。EPT的全面数学概述在单一类型的公式中协调了几种EPT技术,并深入了解了它们如何作用于数据以及它们的数据需求。此外,这篇评论描述了基于机器学习的算法。可根据要求提供几种微分和迭代积分方法的Matlab代码。
    Electrical properties tomography (EPT) is an imaging method that uses a magnetic resonance (MR) system to non-invasively determine the spatial distribution of the conductivity and permittivity of the imaged object. This manuscript starts by providing clear definitions about the data required for, and acquired in, EPT, followed by comprehensively formulating the physical equations underlying a large number of analytical EPT techniques. This thorough mathematical overview of EPT harmonizes several EPT techniques in a single type of formulation and gives insight into how they act on the data and what their data requirements are. Furthermore, the review describes machine learning-based algorithms. Matlab code of several differential and iterative integral methods is available upon request.
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  • 文章类型: Journal Article
    BACKGROUND: Physical therapy, including percussion, inversion, vibration and combinations, was clinically performed to improve the stone free rate (SFR) following lithotripsy procedures. However, physical therapy is not widely accepted in clinical practice owing to lack of high level evidence support and a standard protocol. The present meta-analysis aimed to evaluate the efficacy and safety of physical therapy in improving SFR following extracorporeal shockwave lithotripsy (ESWL) and retrograde intrarenal surgery (RIRS).
    METHODS: Systematic review of literature from PubMed, Scopus, Cochrane library and Embase was performed in March 2019. The efficacy and safety of physical therapy after ESWL and RIRS were assessed by meta-analysis of SFR and complication rate.
    RESULTS: A total of 8 prospective studies with 1065 patients were enrolled. When compared to non-intervention, physical therapy provided a higher SFR (OR:3.38, 95% CI: 2.45-4.66, p < 0.0001) at all time points (week 1, week 2 and month 1), while there was no significant difference in complications such as hematuria, lumbago, dizziness and urinary tract infection (OR: 0.84; 95%CI: 0.62-1.13; p = 0.237). In subgroup analysis of different stone locations, lower calyx stone (OR: 3.51; 95%CI: 2.21-5.55; p < 0.0001), upper ureter and renal pelvic stones (OR:2.79; 95%CI:1.62-4.81; p = 0.0002) had a higher SFR after physical therapy, while there was no significant improvement in SFR in upper and middle calyx stones. In subgroup analysis of different techniques, EPVL (external physical vibration lithecbole, OR:3.47; 95%CI:2.24-5.37; p < 0.0001) and PDI (percussion, diuresis and inversion, OR:3.24; 95%CI:2.01-5.21; p < 0.0001) were both effective in improving SFR when compared to non-intervention.
    CONCLUSIONS: Physical therapy is effective in improving the SFR after ESWL and RIRS, especially for lower calyx stones, upper ureter and renal pelvic stones, while without significant side effects. External physical vibration lithecbole (EPVL) might provide a relative uniformed and repeatable protocol for clinical practice of physical therapy.
    BACKGROUND: PROSPERO 2019 CRD42019130228 .
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  • 文章类型: Case Reports
    非产褥期子宫内翻是非常罕见的事件。我们报道了第一例由于子宫腺肌病引起的非产褥期子宫内翻。在异常阴道肿块的情况下,建议进行磁共振成像。以便可以考虑这种可能的子宫病因。
    Nonpuerperal uterine inversion is a very rare event. We reported on the first ever case of nonpuerperal uterine inversion due to adenomyosis. Magnetic resonance imaging is recommended in cases with an unusual vaginal mass, so that this possible uterine etiology can be taken into consideration.
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  • 文章类型: Journal Article
    踝关节内翻韧带扭伤是最常见的运动损伤之一。最直接的方法是调查真实的伤害事件,但是在测试参与者身上复制是不道德的,也是不可能的。模拟器包括倾斜平台,活板门,和支点装置被设计用来模拟实验室的踝关节内翻运动。反转角度是早期设计中唯一考虑的元素;然而,在临床观察中,踝关节扭伤由内翻和跖屈组成。反演速度是增加模拟真实性的另一个参数。这篇综述总结了模拟器,并旨在比较和对比它们的特征和设置。
    Ankle inversion ligamentous sprain is one of the most common sports injuries. The most direct way is to investigate real injury incidents, but it is unethical and impossible to replicate on test participants. Simulators including tilt platforms, trapdoors, and fulcrum devices were designed to mimic ankle inversion movements in laboratories. Inversion angle was the only element considered in early designs; however, an ankle sprain is composed of inversion and plantarflexion in clinical observations. Inversion velocity is another parameter that increased the reality of simulation. This review summarised the simulators, and aimed to compare and contrast their features and settings.
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  • 文章类型: Journal Article
    在至少10年的时间里,越来越多的病例报告和小型患者系列证明了染色体q臂的某些结构变化之间的关联。3(插入,倒置,易位(3;3)或与其他染色体易位)和血小板产生增加和形态巨核细胞异常的迹象。对64例此类患者的已发表数据的分析表明,与第3号之间的易位相比,两条3号染色体之间的重排与血小板计数和骨髓中巨核细胞的频率显着提高有关。3和其他染色体。Further,巨核细胞增生主要是由于异常小的巨核细胞,通常有低小叶核。这些定量的,血小板生成的质变与3q21和8d3q26的同时断裂和这些条带的并列相关,从而形成条带序列3q21::q26。显然,该带序列特异性刺激和改变血小板生成。
    During the least 10 years a growing number of case reports arid small patient series have demonstrated an association between certain structural changes of the q arm of chromosom\'e no. 3 (insertion, inversion, translocation (3; 3) or translocation with other chromosomes) and signs of increased platelet production and morphologic megakaryocyte abnormalitieis. Analysis of published data on 64 such patients now demonstrate that rearrangements between the two chromosomes 3 are associated with significantly higher platelet counts and higher frequencies of megakaryocytes in the marrow than are translocations between no. 3 and other chromosomes. Further, the megakaryocyte hyperplasia is due primarily to abnormally small megakaryocytes, often with hypolobulated nuclei. These quantitative,and qualitative changes of thrombopoiesis are associated with coincident breaks in 3q21 an8d 3q26 and juxtaposition of these bands so that the band sequence 3q21::q26 is formed. Apparently, this band sequence specifically stimulates and changes thrombopoiesis.
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  • 文章类型: Journal Article
    人们普遍认为,人脸的处理方式与其他对象不同。然而,对于描述这种“特殊”面部处理的广泛术语的含义缺乏共识(例如,整体和配置)和面部中感知相关的信息(例如,关系属性和配置)。本文将回顾现有的整体/配置处理模型,讨论它们在概念上是如何不同的,并回顾用于利用这些概念的各种措施。通常,我们赞成这样一种模型,其中面部的整体处理包括特征之间的某些或全部相互关系,并且具有针对特征的单独编码。然而,该模型的某些方面仍不清楚。我们建议使用移动的人脸作为澄清哪些类型的信息包含在人脸的整体表示中的一种方式。
    It is widely agreed that the human face is processed differently from other objects. However there is a lack of consensus on what is meant by a wide array of terms used to describe this \"special\" face processing (e.g., holistic and configural) and the perceptually relevant information within a face (e.g., relational properties and configuration). This paper will review existing models of holistic/configural processing, discuss how they differ from one another conceptually, and review the wide variety of measures used to tap into these concepts. In general we favor a model where holistic processing of a face includes some or all of the interrelations between features and has separate coding for features. However, some aspects of the model remain unclear. We propose the use of moving faces as a way of clarifying what types of information are included in the holistic representation of a face.
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