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Automatic Pathological Lung Segmentation in Low-dose CT Image using Eigenspace Sparse Shape Composition
摘要： Segmentation of lungs with severe pathology is a nontrivial problem in clinical application. Due to complex structures, pathological changes, individual differences and low image quality, accurate lung segmentation in clinical 3D CT images is still a challenging task. To overcome these problems, a novel dictionary-based approach is introduced to automatically segment pathological lungs in 3D low-dose CT images. Sparse shape composition is integrated with eigenvector space shape prior model, called eigenspace sparse shape composition, to reduce local shape reconstruction error caused by weak and misleading appearance prior information. To initialize the shape model, a landmark recognition method based on discriminative appearance dictionary is introduced to handle lesions and local details. Furthermore, a new vertex search strategy based on gradient vector flow field is also proposed to drive shape deformation to target boundary. The proposed algorithm is tested on 78 3D low-dose CT images with lung tumors. Compared to state-of-the-art methods, the proposed approach can robustly and accurately detect pathological lung surface.
关键词： gradient vector flow,Pathological lung segmentation,discriminative appearance dictionary,eigenspace sparse shape composition
更新于2025-09-23 15:22:29
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Localized Surface Plasmon Resonance Sensor Based at Metallic Sphere Dimer Particle
摘要： By the cooling holes in aero-engine turbine blade as the research object, this study focuses on two kinds of electrochemical machining(ECM) methods, which are mix gas added to the nonlinear electrolyte (NaNO3) and non-mixed gas. Mixed and non-mixed gas ECM experiments of turbine blade cooling holes were carried out respectively. The corresponding two-dimensional CAD model of cooling hole was constructed combined with the experimental data and theoretical analysis. Numerical simulation analysis was carried out of the flow field base on the above models by using the fluid dynamics analysis software FLUENT. The influence flow velocity and flow velocity distribution on the machining accuracy and efficiency of ECM were investigated in detail. The vortex zone distribution of gas-NaNO3 mixed phase flow field and single NaNO3 solution flow field was analyzed qualitatively. The simulation results indicated that the flow velocity in the machining gap with mixed gas was significantly higher than the velocity during ECM process for cooling holes. The electrolytic products and heat were washed away completely, the electrolyte can be updated in time. Fluid vortex zone distribution was improved obviously, the flow field distribution became more uniform after mixed gas in ECM process. The machining accuracy and efficiency for cooling holes making may be improved greatly with gas mixed in electrolyte NaNO3.
关键词： electrolytic machining,mixed gas,cooling hole,gas-liquid two-phase flow,CFD
更新于2025-09-23 15:22:29
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Flow Cytometry Identifies a Spectrum of Maturation in Myeloid Neoplasms Having Plasmacytoid Dendritic Cell Differentiation
摘要： Background: Neoplasms derived from plasmacytoid dendritic cells (PDCs) are currently divided into two broad categories: mature PDC proliferations associated with myeloid neoplasms (MPDMN) and blastic plasmacytoid dendritic cell neoplasm (BPDCN); only BPDCN is recognized in the WHO 2016 classification of hematopoietic neoplasms. We present seven patients with high grade myeloid neoplasms (MNs), mostly acute leukemias, having a spectrum of PDC differentiation and not fitting with MPDMN or BPDCN. Methods: We analyzed seven MN cases having increased myeloblasts and prominent CD56-negative PDC proliferations comprising 5–26% of bone marrow or blood cellularity as measured by flow cytometry. The cases included five acute myeloid leukemia (three FAB M4 subtype, two unclassified), one mixed phenotype acute leukemia, and one case of unclassified MN. Results: Six cases demonstrated immunophenotypic evidence of PDC differentiation from leukemic blasts, based on variable expression of CD34, CD45, CD123, and CD304 by the leukemic cells. Four cases had circulating PDC populations in blood. None of the cases met clinical or pathologic criteria for BPDCN. Morphologic review was available for four acute leukemia cases and demonstrated either nodular or interstitial infiltrates of PDCs. All cases had an aggressive clinical course, and three cases had FLT3 ITD mutation. Conclusions: These cases demonstrate that high grade MNs, in particular AML, can exhibit PDC differentiation, with or without monocytic differentiation, in a manner distinct from MPDMN or BPDCN. The existence of MNs with immature PDC proliferations suggests that there is a broader spectrum of PDC-associated neoplasms than currently recognized.
关键词： plasmacytoid dendritic cell,flow cytometry,acute myeloid leukemia,myeloid neoplasm,immunophenotype
更新于2025-09-23 15:22:29
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Plaque characteristics and slow flow during percutaneous coronary intervention of irregular protrusion by optical coherence tomography
摘要： Irregular protrusion on optical coherence tomography (OCT) is associated with clinical events and target lesion revascularization. We investigated clinical and procedure characteristics, plaque characteristics, slow flow after stent implantation, and clinical outcomes with irregular protrusion using OCT. Eighty-four lesions in 76 patients undergoing OCT before percutaneous coronary intervention were evaluated. Irregular protrusion was defined as protrusion of material with an irregular surface into the lumen between stent struts with a maximum height of ≥100 μm. Lesions with irregular protrusion were found in 56% (47/84). Compared with lesions without irregular protrusion, those with irregular protrusion had significantly higher low-density lipoprotein cholesterol (LDL-C) levels (108 ± 31 mg/dl vs. 95 ± 25 mg/dl, P = 0.044); a tendency toward decreased use of statins [44% (19/43) vs. 67% (22/33), P = 0.065]; significantly larger reference vessel diameter (3.12 ± 0.53 mm vs. 2.74 ± 0.63 mm, P = 0.004); more frequent slow flow after stent implantation [38% (18/47) vs. 11% (4/37), P = 0.006]; higher incidence of thin-cap fibroatheromas [TCFAs; 49% (23/47) vs. 5% (2/37), P < 0.001]; plaque rupture [40% (19/47) vs. 16% (6/37), P = 0.018]; and a tendency higher incidence of 1-year adverse clinical outcomes (death, acute myocardial infarction, acute coronary syndrome, or target lesion revascularization) [12% (5/43) vs. 0% (0/33), P = 0.075]. In conclusion, irregular protrusion on OCT was associated with high plaque vulnerability, higher LDL-C, less frequent use of statin, larger vessel diameter, slow flow after stent implantation, and 1-year adverse clinical outcomes.
关键词： Slow flow,Optical coherence tomography,Irregular protrusion
更新于2025-09-23 15:22:29
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[IEEE 2018 26th European Signal Processing Conference (EUSIPCO) - Rome (2018.9.3-2018.9.7)] 2018 26th European Signal Processing Conference (EUSIPCO) - Unsupervised calibration of RGB-NIR capture pairs utilizing dense multimodal image correspondences
摘要： In this paper, we propose an unsupervised calibration framework aimed at calibrating RGB plus Near-InfraRed (NIR) capture setups. We favour dense feature matching for the case of multimodal data and utilize the Scale-Invariant Feature Transform (SIFT) flow, previously developed for matching same-category image objects. We develop an optimization procedure that minimizes the global disparity field between the two multimodal images in order to adapt SIFT flow for our calibration needs. The proposed optimization substantially increases the number of inliers and yields more robust and unambiguous calibration results.
关键词： multimodal stereo,calibration,SIFT flow,NIR,features matching
更新于2025-09-23 15:22:29
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Dopamine Binding and Analysis in Undiluted Human Serum and Blood by the RNA-Aptamer Electrode
摘要： Specific analysis of such neurotransmitters as dopamine by the aptamer electrodes in biological fluids is detrimentally affected by non-specific adsorption of media, particularly pronounced at positive charges of the electrode surface at which dopamine oxidizes. Here, we show that dopamine analysis at the RNA-aptamer/cysteamine-modified electrodes is strongly inhibited in undiluted human serum and blood due to non-specific interfacial adsorption of serum and blood components. We demonstrate that non-specific adsorption of serum proteins (but not of blood components) could be minimized when analysis is performed in a flow and injections of serum samples are followed by washing steps in a phosphate buffer solution (PBS) carrier. Under those conditions, the dopamine-aptamer binding affinity in whole human serum of (1.9±0.3)×104 M-1 s-1 was comparable to (3.7±0.3)×104 M-1 s-1 found in PBS, and the dopamine oxidation signal linearly depended on the dopamine concentration, providing the sensitivity of analysis of 73 ± 3 nA μM-1 cm-2 and the LOD of 114 ± 8 nM. The flow-injection apatmer-electrode system was used for direct analysis of basal levels of dopamine in undiluted human serum samples, without using any physical separators (membranes) or filtration procedures. The results suggest a simple strategy for combatting biosurface fouling most pronounced at positive electrode potentials and assist in designing more efficient antifouling strategies for biomedical applications.
关键词： Human serum,Blood,Surface fouling,RNA aptamer electrode,Dopamine,Chronoamperometry,Electrochemical Impedance,Flow-through cell
更新于2025-09-23 15:22:29
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The effects of gas flow pattern on the generation of ozone in surface dielectric barrier discharge
摘要： Ozone production utilizing surface dielectric barrier discharge (SDBD) was experimental studied for different flow patterns considering the influences of transversal flow, lateral flow and different lateral flow positions. Results show that the flow patterns have a remarkable impact on the ozone yield by affecting the uniformity and turbulence of gas flow. Meanwhile, distributing the O2 flow rate according to the intensity of the plasma reaction would also increase the generation efficiency of SDBD for ozone production. By improving the uniformity and introducing the lateral flow to the transversal flow, the highest ozone yield was obtained in flow pattern “F”. In this case, the ozone yield increased by 28.4% to 131 g/kWh from 102.8 g/kWh in flow pattern “A”.
关键词： flow pattern,ozone generation,surface barrier discharge
更新于2025-09-23 15:22:29
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Selective Monitoring of Oxyanion Mixtures by a Flow System with Raman Detection
摘要： Raman spectroscopy is a selective detection system scarcely applied for the flow analysis of solutions with the aim of detecting several compounds at once without a previous separation step. This work explores the potential of a portable Raman system in a flow system for the selective detection of a mixture of seven oxyanions (carbonate, sulphate, nitrate, phosphate, chlorate, perchlorate, and thiosulphate). The specific bands of these compounds (symmetric stretching Raman active vibrations of carbonate at 1068 cm?1, nitrate at 1049 cm?1, thiosulphate at 998 cm?1, phosphate at 989 cm?1, sulphate at 982 cm?1, perchlorate at 935 cm?1, and chlorate at 932 cm?1) enabled their simultaneous detection in mixtures. Although the oxyanions’ limit of detection (LOD) was rather poor (in the millimolar range), this extremely simple system is very useful for the single-measurement detection of most of the oxyanions in mixtures, without requiring a previous separation step. In addition, quantitative determination of the desired oxyanion can be performed by means of the corresponding calibration line. These are important advantages for controlling in-line processes in industries like those manufacturing fertilizers, pharmaceuticals, chemicals, or food, among others.
关键词： oxyanions,flow analysis,Raman detection
更新于2025-09-23 15:22:29
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Stability of eosin-5'-maleimide dye used in flow cytometric analysis for red cell membrane disorders
摘要： The eosin-5'-maleimide (EMA) binding test using flow cytometry is a common method to measure reduced mean channel fluorescence (MCF) of EMA-labeled red blood cells (RBCs) from patients with red cell membrane disorders. The basic principle of the EMA-RBC binding test involves the covalent binding of EMA to lysine-430 on the first extracellular loop of band 3 protein. In the present study, the MCF of EMA was analyzed for samples derived from 12 healthy volunteers (controls) to determine the stability (i.e., the percentage decrease in fluorescence) of EMA over a period of 1 year. Comparison of periodical MCF readings over time, that is, at 2-month intervals, showed that there were no significant changes in mean channel fluorescence for up to 6 months; however, there was a significant decrease in MCF at 8 months. For optimal dye utilization, EMA remained stable only for up to 6 months. Therefore, we recommend reconstitution of the dye every 6 months when implementing this test and storage at -80oC in dark conditions.
关键词： Flow Cytometry,Red Blood cells,Hereditary spherocytosis
更新于2025-09-23 15:22:29
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Robust artifact-free high dynamic range imaging of dynamic scenes
摘要： The irradiance range of the real-world scene is often beyond the capability of digital cameras. Therefore, High Dynamic Range (HDR) images can be generated by fusing images with different exposure of the same scene. However, moving objects pose the most severe problem in the HDR imaging, leading to the annoying ghost artifacts in the fused image. In this paper, we present a novel HDR technique to address the moving objects problem. Since the input low dynamic range (LDR) images captured by a camera act as static linear related backgrounds with moving objects during each individual exposures, we formulate the detection of foreground moving objects as a rank minimization problem. Meanwhile, in order to eliminate the image blurring caused by background slightly change of LDR images, we further rectify the background by employing the irradiances alignment. Experiments on image sequences show that the proposed algorithm performs significant gains in synthesized HDR image quality compare to state-of-the-art methods.
关键词： Multi-exposure fusion,High dynamic range imaging,Rank minimization,Motion blur,Optical flow,Ghost removal
更新于2025-09-23 15:22:29