- 标题
- 摘要
- 关键词
- 实验方案
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ANALYSIS OF POWER FLOW BY POYNTING VECTORS FOR ELECTROMAGNETIC WAVE ABSORBERS USING FREQUENCY SELECTIVE SURFACES
摘要： The power ?ow for electromagnetic wave absorbers consisting of pattern conductor layers acting as frequency selective surfaces, absorption layers, and short circuit layers was investigated by Poynting vectors. A method was developed to evaluate the ?ow of electromagnetic wave power by an electromagnetic wave absorber upon irradiation with electromagnetic waves. The results indicate that the electromagnetic wave absorption phenomenon involves generation of real power, a real part of the time averaged Poynting vector, which moves horizontally along the pattern surface after the incident wave has irradiated the pattern conductor from the vertical direction, and the direction of power ?ow changes to enter the polymer layer from the pattern interval, causing an accumulation of power inside the polymer layer, followed by absorption, which is converted into heat due to the loss factor.
关键词： Electromagnetic wave absorbers,Absorption layers,Power flow,Frequency selective surfaces,Poynting vectors
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE 7th Global Conference on Consumer Electronics (GCCE) - Nara, Japan (2018.10.9-2018.10.12)] 2018 IEEE 7th Global Conference on Consumer Electronics (GCCE) - Blood Circulation Based on PPG Signals for Thermal Comfort Evaluation
摘要： This paper presents a new index for monitoring transition of blood circulation from Photoplethysmogram (PPG) signals for thermal comfort evaluation of users. Heat dissipation reaction through the dilation of blood vessels is person's intrinsic ability to control the thermal comfort. When body temperature is higher than normal temperature, blood circulation changes according to the dilation of blood vessels in distal end of the extremities. Blood circulation is often evaluated by an index of peripheral resistance corresponding to changes in blood flow velocity such as systolic/diastolic ratio (S/D) of flow velocities, resistance index and the pulsatility index. Unfortunately, such an index cannot be utilized in daily life for healthcare with using fitness trackers since the blood flow velocity is measured by either an ultrasonic Doppler blood flowmeter (UDF) or a Laser-Doppler flowmeter. Therefore, we propose a new index which is easily acquirable from PPG signals. First, a couple of variables correlating to the blood flow velocity is calculated from a rate of volumetric strain of Photoplethysmogram signals. Then the new index can be obtained as difference of these variables. Experimental results show the effectiveness of this index by confirming high correlation with S/D of UDF.
关键词： Peripheral blood circulation,volumetric strain,blood flow velocity,Photoplethysmogram signals
更新于2025-09-04 15:30:14
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[IEEE 2018 IEEE 7th Global Conference on Consumer Electronics (GCCE) - Nara, Japan (2018.10.9-2018.10.12)] 2018 IEEE 7th Global Conference on Consumer Electronics (GCCE) - Noise Resistance Global Method Optical Flow Using Adaptive Lorentzian Influence
摘要： This paper presents the using of adaptive Lorentzian influence with the global method optical flow for noise resistance on the visual progression. In particular, optical flow is the pattern of apparent motion of image objects between two consecutive frames caused by the movement of object or camera. It is 2D vector field where each vector is a displacement vector showing the movement of points from the first frame to second. When the image flow is degraded by noise, the performance for approximating the vector in optical flow is incorrect. With adaptive Lorentzian influence, we ensure more desirable noise resistance in global method optical flow in our experiment. We also test the using of adaptive Lorentzian influence over many noise resistance models when they proceed on global method optical flow. Many intensities of the additive white Gaussian (AWG) noise from low to high intensity of noise are utilized in our experiment to ensure our proposed method.
关键词： Lorentzian influence,optical flow,additive white Gaussian noise,2D vector
更新于2025-09-04 15:30:14
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High-sensitivity lateral flow immunoassay with a fluorescent lanthanide nanoparticle label
摘要： Lateral flow (LF) immunoassays are commonly used for point-of-care testing and typically incorporate visually read reporters, such as gold particles. To improve sensitivity and develop quantitative LF immunoassays, visual reporters can be replaced by fluorescent reporters detected by an instrument. In this study, we used fluorescent europium(III) chelate doped nanoparticle (Eu-np) reporters to develop a quantitative high-sensitivity LF immunoassay for free prostate specific antigen (fPSA). Furthermore, we tested different simplified formats of the assay and the effect of different modifiable parameters on the detection limit of the assay: dynamic range, assay duration and number of assay steps. The molar detection limits of the different assay formats were compared with published detection limits of LF immunoassays with different reporters. The cutoff was calculated from 11 female serum samples. The detection limit of the sensitivity optimized fPSA assay with fPSA spiked into pooled female serum was 0.01 ng/ml, which is approximately 100-fold lower than the most sensitive gold particle LF assays and 10-fold lower than other Eu-np and carbon nanoparticle based LF immunoassays. Thus, Eu-np reporters can be used to develop highly sensitive and quantitative LF immunoassays.
关键词： Lateral flow,Fluorescent,Prostate specific antigen,Immunoassay
更新于2025-09-04 15:30:14
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Evaluation of Exfoliated Graphite to Graphene in Polyamide 66 Using Novel High Shear Elongational Flow
摘要： Graphene has been publicized as the game changing material of this millennium. To this day, scalable production leading to exceptional material properties has been difficult to attain. Most methods require harsh chemicals, which result in destroying the graphene surface. A method was developed, exploiting high speed elongational flow in a novel designed batch mixer; creating a distribution of pristine few to many layer graphene flakes. The method focuses on exfoliating in a molten polyamide 66 (PA66) matrix, creating a graphene reinforced polymer matrix composite (G-PMC). The process revealed that high speed elongational flow was able to create few layer graphene. Graphite exfoliation was found driven in part by diffusion, leading to intercalation of PA66 in graphite. The intercalated structure lead to increases in the hydrogen bonding domain, creating anisotropic crystal domains. The thermal stability of the G-PMC was found to be dependent to the degree of exfoliation, PA66 crystal structure and composite morphology. The aim of this research is to characterize uniquely produced graphene containing polymer matrix composites using a newly created elongational flow field. Using elongational flow, graphite will be directly exfoliated into graphene within a molten polymer.
关键词： polyamide 66,elongational flow,graphene polymer matrix composite,hydrogen bond,graphene
更新于2025-09-04 15:30:14
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Automated syringe-pump-based flow-batch analysis for spectrophotometric determination of trace hexavalent chromium in water samples
摘要： In this work, we established an automated spectrophotometric method for determining hexavalent chromium in water samples using an integrated syringe pump-based environmental water analyzer (iSEA) based on the classic 1,5-diphenylcarbazide chemistry. The device was computer-controlled with programs written by LabVIEW. The effects of reagent concentration, sample salinity and foreign ion interferences were investigated. Standard solutions (GBW(E)081584-1) were used to test the accuracy of the method. When equipped with a 5 cm Z-shaped flow cell, the detection limit was 0.024 μM with sample throughput of >30 h-1. In order to meet the requirements for trace Cr(VI) determination, the system was modified with a 2.5 m liquid waveguide capillary cell (internal diameter of 0.55 mm). The sample consumption was less than 2.1 mL. The detection limit was 0.54 nM with sample throughput of 20 h-1 and good linearity with R2=0.9985 (n=110, obtained over 14 days). The two methods were successfully applied to determine Cr(VI) level in different water samples including tap water, river water, industrial wastewater and 37 brands of bottled water with spiked recovery in the range of 89.5%-117%.
关键词： hexavalent chromium,bottled water,Flow-batch analysis,syringe pump,liquid waveguide capillary cell
更新于2025-09-04 15:30:14
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Flow cytometry for fast screening and automated risk assessment in systemic light-chain amyloidosis
摘要： Early diagnosis and risk stratification are key to improve outcomes in light-chain (AL) amyloidosis. Here we used multidimensional-flow-cytometry (MFC) to characterize bone marrow (BM) plasma cells (PCs) from a series of 166 patients including newly-diagnosed AL amyloidosis (N = 94), MGUS (N = 20) and multiple myeloma (MM, N = 52) vs. healthy adults (N = 30). MFC detected clonality in virtually all AL amyloidosis (99%) patients. Furthermore, we developed an automated risk-stratification system based on BMPCs features, with independent prognostic impact on progression-free and overall survival of AL amyloidosis patients (hazard ratio: ≥ 2.9;P ≤ .03). Simultaneous assessment of the clonal PCs immunophenotypic protein expression profile and the BM cellular composition, mapped AL amyloidosis in the crossroad between MGUS and MM; however, lack of homogenously-positive CD56 expression, reduction of B-cell precursors and a predominantly-clonal PC compartment in the absence of an MM-like tumor PC expansion, emerged as hallmarks of AL amyloidosis (ROC-AUC = 0.74;P < .001), and might potentially be used as biomarkers for the identification of MGUS and MM patients, who are candidates for monitoring pre-symptomatic organ damage related to AL amyloidosis. Altogether, this study addressed the need for consensus on how to use flow cytometry in AL amyloidosis, and proposes a standardized MFC-based automated risk classification ready for implementation in clinical practice.
关键词： bone marrow,plasma cells,light-chain amyloidosis,risk assessment,flow cytometry
更新于2025-09-04 15:30:14
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[IEEE 2018 53rd International Universities Power Engineering Conference (UPEC) - Glasgow, United Kingdom (2018.9.4-2018.9.7)] 2018 53rd International Universities Power Engineering Conference (UPEC) - Manage Reverse Power Flow and Fault Current Level in LV Network with High Penetration of Small Scale Solar and Wind Power Generation
摘要： High penetration level of rooftop small-scale renewable energy generation (REG) such as solar and wind power into the existing low voltage (LV) network would cause the flow of power in reverse direction. This would also vary the level of short-circuit current required for relays to operate. Relay settings would be required to properly detect the unpredictable isolate the faulty section. This paper investigates the impact of residential distributed generation (DG) penetration level on the typical UK low voltage network protection system. Studies were commenced to properly charge and discharge the home connected energy storage battery (ESB). ESB is used as a remedial measure to confine the flow of reverse power due to rooftop DGs. Penetration level DGs are modeled based on proper ESB charging and discharging states in daily load cycle. Short circuit analysis results are compared with the UK passive network to investigate the impact of the DG on the short circuit currents at distribution transformer.
关键词： UK distribution network,short circuit analysis,Rooftop DG penetration,energy storage batteries,reverse power flow
更新于2025-09-04 15:30:14
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Ensayo Pictórico: Control imagenológico de aneurismas tratados ?Qué examen elegir?
摘要： Treatment of intracranial ruptured and unruptured aneurysms can be performed with surgical (vascular clips) or endovascular procedures (coils, stents, flow diverters). There are several devices and techniques for endovascular treatment. Knowledge of this techniques allows physicians to choose and interpret accurately imaging modalities for non-invasive follow-up. Through a pictorial essay of imaging follow-up of treated intracranial aneurysms we show the differences in characterization with computed tomography angiography, magnetic resonance angiography without contrast (time of flight or “TOF” technique), contrast enhanced MR angiography (C+) and digital subtraction angiography (DSA). Additionally we recommend imaging modalities for each treatment device.
关键词： brain aneurysms,flow diverter,vascular clips,intracranial stent,imaging follow-up,coils
更新于2025-09-04 15:30:14
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A Flow Cytometry‐Based Assay for High‐Throughput Detection and Quantification of Neutrophil Extracellular Traps in Mixed Cell Populations
摘要： Neutrophil extracellular traps (NETs) are web-like structures composed of decondensed chromatin and antimicrobial proteins that are released into the extracellular space during microbial infections. This active cell death program is known as NETosis. To date, fluorescence microscopy is the widely accepted method for visualization and quantification of NETs. However, this method is subjective, time consuming and yields low numbers of analyzed polymorphonuclear cells (PMNs) per sample. Increasing interest has emerged on the identification of NETs using flow cytometry techniques. However, flow cytometry analysis of NETs requires particular precautions for sample preparation to obtain reproducible data. Herein, we describe a flow cytometry-based assay for high-throughput detection and quantification of NETosis in mixed cell populations. We used fluorescent-labeled antibodies against cell markers on PMNs together with a combination of nucleic acid stains to measure NETosis in whole blood (WB) and purified PMNs. Using plasma membrane-impermeable DNA-binding dye, SYTOX Orange (SO), we found that cell-appendant DNA of NETting PMNs were positive for SO and DAPI. The combination of optimally diluted antibody and nucleic acid dyes required no washing and yielded low background fluorescence. Significant correlations were found for NETosis from WB and purified PMNs. We then validated the assay by comparing with time-lapse live cell fluorescence microscopy and determined very good intraassay and interassay variances. The assay was then applied to a disease associated with NETosis, systemic lupus erythematosus (SLE). We examined PMA-induced NETosis in peripheral PMNs from SLE patients and controls and in bone marrow PMNs from multiple murine models. In summary, this assay is observer-independent and allows for rapid assessment of a large number of PMNs per sample. Use of this assay does not require sophisticated microscopic equipment like imaging flow cytometers and may be a starting point to analyze extracellular trap formation from immune cells other than PMNs.
关键词： neutrophils,flow cytometry,extracellular traps
更新于2025-09-04 15:30:14