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1.
Clinical information about a variety of disorders is available through blood cell counting, which is usually done by manual methods. However, manual methods are complex, time-consuming and susceptible to the subjective experience of inspectors. Although many efforts have been made to develop automated blood cell counting algorithms, the complexity of blood cell distribution and the highly overlapping nature of some red blood cells (RBCs) remain significant challenges that limit the improvement of analytical accuracy. Here, we proposed an end-to-end method for blood cell counting based on deep learning. Firstly, U-Net++ was used to segment the whole blood cell image into several regions of interest (ROI), and each ROI contains only one single cell or multiple overlapping cells. Subsequently, YOLOv5 was used to detect blood cells in each ROI. Specifically, we proposed several strategies, including fine classification of RBCs, adaptive adjustment for non-maximal suppression (NMS) threshold and blood cell morphology constraints to improve the accuracy of detection. Finally, the detection outcomes for each ROI were combined and superimposed. The results show that our method can effectively address the issue of high overlap and precisely segment and detect blood cells, with a 98.18% accuracy rate for blood cell counting.  相似文献   
2.
离子液体浮选分离模拟乏燃料中的稀土元素   总被引:1,自引:1,他引:1  
从乏燃料中高效分离稀土元素(中子毒物)是实现乏燃料再生循环利用的关键步骤。利用双有机相离子液体选择性浮选分离乏燃料中的稀土元素,使氧化铀和稀土氧化物几乎不被溶解,实现两者固相之间的分离,避免了二次废液的产生,具有节能和环保的双重意义。以2-乙基己基膦酸单-2-乙基己基酯(P507)为稀土元素的捕收剂、煤油或油酸为稀释剂,以1-丁基-3-甲基咪唑六氟磷酸盐([C4mim][PF6])和1-丁基-3-甲基咪唑双三氟甲烷磺酰亚胺盐([C4mim][Tf2N])两种离子液体作为浮选体系的另一相,优化得到了浮选分离稀土氧化物的最佳条件。结果发现:浮选分离去除率随着混合物中初始Nd含量以及浮选次数的增加而增加。另外,对所有稀土元素与U3O8分别组成的二元体系混合物进行了浮选分离研究,发现在相同条件下,该体系对不同稀土元素的分离也不同,浮选分离的去除率与稀土氧化物的密度有一定的相关性。在此基础上,利用浮选机开展了工艺化的初步探索,发现该浮选体系对Nd的去除率可达80%以上。  相似文献   
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4.
《Thin solid films》1986,137(2):207-214
Conducting transparent films of indium tin oxide were deposited by 100 eV oxygen-ion-assisted deposition. A refractive index of 2.13 at 550 nm was obtained for films deposited onto ambient temperature substrates. The refractive index decreased with increasing substrate temperature to a value of 2.0 at 400°C. The sheet resistance of films 135 nm thick decreased from 800 Ω/□ for layers deposited onto room temperature substrates to around 25 Ω/□ at 400°C. Structural studies revealed that ion-assisted deposition onto ambient temperature substrates produced amorphous films, and that at temperatures above 100°C the films exhibit In2O3 crystallinity. In addition, it was found that the number of voids in the ion-bombarded films was reduced relative to that in films produced by conventional reactive evaporation.  相似文献   
5.
A relatively simple mathematical procedure for the reconstruction of the 3-dimensional (3D) image of the left ventricle (LV) of the heart is presented. The method is based on the assumption that every ray whoch emanates from the midpoint of the long axis of the 3D body crosses the surface boundary of the ventricle at one and only one point. The coordinates ri, φi, θi of the data points on, say, the outer boundary, (i.e., the epicardium) are calculated in a spherical coordinate system having its origin in the midpoint of the long axis. The problem of defining the coordinates of a prescribed grid point on the boundary is treated as an interpolation problem for the function r = r(φ, θ), defined in the rectangle 0 ≤ φ ≤ 2π; 0 ≤ θπ with ri given in the points (φi, θi).  相似文献   
6.
Human endometrium is an incredibly dynamic tissue undergoing cyclic regeneration and shedding during a woman’s reproductive life. Endometrial mesenchymal stromal/stem-like cells (eMSC) contribute to this process. A hypoxic niche with low oxygen levels has been reported in multiple somatic stem cell types. However, the knowledge of hypoxia on eMSC remains limited. In mice, stromal stem/progenitor cells can be identified by the label-retaining technique. We examined the relationship between the label-retaining stromal cells (LRSC) and hypoxia during tissue breakdown in a mouse model of simulated menses. Our results demonstrated that LRSC resided in a hypoxic microenvironment during endometrial breakdown and early repair. Immunofluorescence staining revealed that the hypoxic-located LRSC underwent proliferation and was highly colocalized with Notch1. In vitro studies illustrated that hypoxia activated Notch signaling in eMSC, leading to enhanced self-renewal, clonogenicity and proliferation of cells. More importantly, HIF-1α played an essential role in the hypoxia-mediated maintenance of eMSC through the activation of Notch signaling. In conclusion, our findings show that some endometrial stem/progenitor cells reside in a hypoxic niche during menstruation, and hypoxia can regulate the self-renewal activity of eMSC via Notch signaling.  相似文献   
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8.
非对称用户数字线路的性能受多个因素影响,故障复杂.本文在简要介绍宽带测试方案的基础上,介绍了一种基于统计决策法的方案.用这样的方案改进原有的测试方案,可以使系统具有更优的精度.  相似文献   
9.
该文搭建迟滞测量实验平台,测量一种用于LED晶圆检测压电执行器的迟滞效应,设计了一种基于长短期记忆(LSTM)神经网络的压电迟滞模型,使用时间序列预测法对压电执行器位移迟滞效应建模。将该模型与传统的Prandtl-Ishlinskii(PI)模型进行对比。实验结果表明,神经网络模型具有较好、较广泛的迟滞建模效果,对于正弦波,位移预测精度保证小于2%;对于衰减正弦波,位移预测精度可保证小于3%。较高的模型预测精度为使用压电执行器进行LED晶圆检测提供了依据。  相似文献   
10.
The autonomic nervous system maintains homeostasis in organisms through complex neural pathways and responds adaptively to changes in the external and internal environment. The fabrication of an artificial autonomic nervous system is reported that replicates combined effects of sympathetic and parasympathetic nerves on cardiac activity and pupillary control, to mimic the regulation of autonomic nervous system to external changes. The artificial autonomic nerve-controlled pupil contraction and relaxation, modulating the rate of heartbeats for normal cardiac rhythm and arrhythmia as reflected by blink rates of a signal indicator. These functions are switched by using a parallel-channeled synaptic transistor with a special n-i-p heterostructure that has a 2D h-BN insulator in the middle to provide barrier against ion injection into the 2D MoS2 bottom n-channel and enable short-term plasticity as induced by acetylcholine, and the electrochemical doping reaction occurred at the P3HT nanowire p-channels on top to enable relatively long-term plasticity as induced by noradrenaline. Low-energy consumption down to femtojoule and an ultrahigh paired-pulse facilitation index up to ≈455% are demonstrated. An artificial neural network based on device characteristics achieves a high recognition accuracy for electrocardiogram patterns. This study extends insights into artificial nerves-inspired biological signal processing and recognition.  相似文献   
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