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关键词： lymphoma   non-hodgkin   classification   artificial intelligence   machine learning   flow cytometry  

摘要： The immunophenotype is a key element to classify B-cell Non-Hodgkin Lymphomas (B-NHL);while it is routinely obtained through immunohistochemistry, the use of flow cytometry (FC) could bear several advantages. However, few FC laboratories can rely on a long-standing practical experience, and the literature in support is still limited;as a result, the use of FC is generally restricted to the analysis of lymphomas with bone marrow or peripheral blood involvement. In this work, we applied machine learning to our database of 1465 B-NHL samples from different sources, building four artificial predictive systems which could classify B-NHL in up to nine of the most common clinico-pathological entities. Our best model shows an overall accuracy of 92.68%, a mean sensitivity of 88.54% and a mean specificity of 98.77%. Beyond the clinical applicability, our models demonstrate (i) the strong discriminatory power of MIB1 and Bcl2, whose integration in the predictive model significantly increased the performance of the algorithm;(ii) the potential usefulness of some non-canonical markers in categorizing B-NHL;and (iii) that FC markers should not be described as strictly positive or negative according to fixed thresholds, but they rather correlate with different B-NHL depending on their level of expression.

关键词： aneurysm   flow diverter   subarachnoid   technique   blood flow  

摘要： We report the case of a patient with subarachnoid hemorrhage and three aneurysms arising from the posterior communicating artery (Pcomm)-P1 complex, treated with endovascular coiling and competitive flow diversion. The largest and likely ruptured Pcomm aneurysm was treated with traditional coiling. Two smaller potentially ruptured aneurysms arose from the distal right posterior cerebral artery (PCA) P1 segment. After a failed attempt to treat with conventional flow diversion across the PCA-P1 segment, the P1 aneurysms were successfully treated with competitive flow diversion distal to the PCA-P1 segment from Pcomm to the P2 segment. Over 12 months, competitive flow diversion redirected flow to the right PCA territory via the internal carotid artery-Pcomm-P2, reducing the size of the PCA-P1 segment and obliterating the P1 aneurysms. Competitive flow diversion treatment should be considered for aneurysms occurring at the circle of Willis when traditional methods are not feasible. Herein, we introduce a novel classification for competitive flow diversion treatment.

关键词： Holm-Staley b-family equation   Large time behavior   Infinite propagation speed  

摘要： In this paper, we study the Holm-Staley b-family equation with weakly dissipative term. Firstly, we show the infinite propagation speed that if the initial datum u(0)(x) has a compact support, the corresponding solution u(x, t) does not have a compact x-support any longer in its lifespan. Then, we obtain the large time behavior of the support of momentum density with the initial data compact supported. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Machine learning   Mass flux   Species segregation   Voidage   Cluster   Circulating fluidized bed  

摘要： Machine learning methods were applied to circulating fluidized bed (CFB) riser data. The goals were to (i) provide insights on various fluidization phenomena through determining the relative dominance of the process variables, and (ii) develop a model to provide predictive capability in the absence of firstprinciples understanding that remains elusive. The Random Forest results indicate radial position had the most dominant influence on local mass flux and species segregation, overall mass flux was the most dominant for local particle concentration, while no variable was particularly dominant or negligible for the local clustering characteristics. Furthermore, the Neural Network can be trained to provide good predictive capability, without any mechanistic understanding needed, if a sufficiently large dataset is used for training and if the input variables fully account for all the effects at play. This study underscores the value of machine learning methods in fluidization to advance understanding and provide adequate predictions. (C) 2020 Elsevier Ltd. All rights reserved.

摘要： The existence of debris flows not only destroys the facilities but also seriously threatens human lives, especially in scenic areas. Therefore, the classification and susceptibility analysis of debris flow are particularly important. In this paper, 21 debris flow catchments located in Huangsongyu Township, Pinggu District, Beijing, China, were investigated. Besides field investigation, a geographic information system, a global positioning system and remote-sensing technology were applied to determine the characteristics of debris flows. This article introduced a clustering validity index to determine the clustering number, and the fuzzy C-means algorithm and factor analysis method were combined to classify 21 debris flow catchments in the study area. The results were divided into four types: debris flow closely related to scale-topography-human activity, topography- human activity-matter source, scale-matter source-geology and topography-scale-matter source-human activity. Nine major factors screened from the classification result were selected for susceptibility analysis, using both the efficacy coefficient method and the combination weighting. Susceptibility results showed that the susceptibility levels of 2 debris flow catchments were high, 6 were moderate and 13 were low. The assessment results were consistent with the field investigation. Finally, a comprehensive assessment including classification and susceptibility evaluation of debris flow was obtained, which was useful for risk mitigation and land use planning in the study area and provided a reference for the research on related issues in other areas.

关键词： 地下水污染   抽出处理法   地下水侧向径流   去除率   流函数  

摘要： 采用抽出处理法修复地下水污染场地需要有一定的回收率,以达到充分净化的目标。当地下水存在侧向径流时,抽出处理法的回收率不一定能够达到100%。对于"一抽一灌"双井单元,井孔扰动下的地下水稳定流场可分为内循环区、外循环区和非循环区,某些情况下内循环区或外循环区不存在。由内循环区的水动力学特性得到回收率的理论公式和变化曲线。回收率取决于地下水侧向径流的方向和相对强度,随抽水流量的增大而增加。回收率公式可用于抽出处理法的井孔设计,地下水污染物的目标去除率越高,所需要的回收率越大。针对北京某试验场,应用该方法进行了回收率优化评估。

关键词： 资本流动管理   资本账户自由化   国际货币基金组织   分类汇总   管理机构   IMF   各国  

摘要： 2019年国际货币基金组织(International Monetary Fund以下简称"IMF")公布了《资本流动管理措施分类》。该分类汇总了2012年11月《资本流动自由化与管理机构观点》(以下简称《机构观点》)正式通过以来,各国资本流动政策的变化(对于《机构观点》采纳前已实行且不曾调整的资本流动政策,IMF仅在评估各国资本账户自由化的整体政策时才会进行讨论)。

关键词： 沉没辊模型   模态试验   附加阻尼   附加质量   流体密度  

摘要： 为准确分析不同流体介质中沉没辊模型附加质量和附加阻尼的变化规律,建立理论计算分析模型,对4种模型在4种流体中进行模态试验。利用锤击法,分别对加杆和不加杆的沉没辊模型进行空气中模态试验,两者结果一致性较高。加杆沉没辊模型的试验结果分析可知,水和液压油中前六阶的频响函数曲线峰值明显,甘油中仅前三阶明显;甘油的黏度变化对模型固有频率的影响较小,但随其黏度的增大其附加阻尼因数增加;随着液体密度增加,模型各阶振型对应的附加质量因数均呈线性增加,且当结构的质量和刚度增大时,其增加的斜率减小;随着结构密度增大,模型附加质量因数减小;所有模型(1,2)和(2,2)振型的附加质量因数大于弯曲振型。

关键词： 玻璃熔体   表面张力   座滴法   试样质量   保温时间  

摘要： 基于座滴法进行玻璃熔体表面张力测量过程中影响因素的研究,探究了承托板材质、试样质量、保温时间对玻璃熔体表面张力测量结果的影响作用规律。结果表明,高纯石墨材料不与玻璃熔体发生润湿,可作为优选承托板材质;随着试样质量增加,仪器测量精度得到提高,优选试样质量范围为0.2~0.4g;随着玻璃试样受热时间延长,玻璃熔体状态趋于平衡,当保温时间达30min,试样熔体液滴体积趋于稳定。根据座滴法的最优测试条件,测定了Al2O3、B2O3质量含量以及Na2O/K2O、CaO/BaO、CaO/MgO比例变化对玻璃熔体表面张力的影响规律,可有效指导玻璃化学组成设计。