- 标题
- 摘要
- 关键词
- 实验方案
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Ultrasensitive detection of avian influenza A (H7N9) virus using surface-enhanced Raman scattering-based lateral flow immunoassay strips
摘要： The development of biosensors that are portable, low-cost, and quantitative has long been sought for rapid, on-site, and timely detection of avian influenza virus (AIV). In this study, an antibody-based Raman lateral flow immunoassay strip was developed to detect AIV H7N9. This LFIA strip used a novel core-shell structure material, AuAg4(cid:3)ATP@AgNPs, as a Raman probe. An antibody specific for AIV and goat anti-mouse IgG antibody were immobilized on a nitrocellulose membrane as the test and control lines, respectively. Accumulation of antibody-virus-antibody-Raman probe complex at the test line could be visualized by the naked eye, and the Raman signal could be quantified using a portable Raman instrument. The testing process for the SERS-based LFIA strips could be completed in 20 min, which avoided the time-cost of current methods for AIV analysis. In our SERS-based biosensor, we estimated the limit of detection (LOD) for H7N9 to be 0.0018 HAU. This value is approximately three orders of magnitude more sensitive than the corresponding HA assays. When testing real sample, the results of the strip test were in accordance with those from real-time PCR testing. In conclusion, the SERS-based LFIA strip proposed in this study shows tremendous potential to detect targets quickly and sensitively using an elegantly simple method.
关键词： AuAg4(cid:3)ATP@AgNPs,Surface-enhanced Raman scattering,Avian influenza virus,Lateral flow immunoassay strips
更新于2025-09-23 15:23:52
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Skin Friction Measurements Using Oil Film Interferometry in a 3-D Supersonic Flowfield
摘要： The application of oil film interferometry (OFI) for the measurement of global skin friction on the surface beneath a complex three-dimensional supersonic flow is explored in this study. The flowfield is produced by a fin-generated oblique shock interacting with a compressible turbulent boundary layer. Measurements were obtained by modifying a comprehensive acquisition and processing software, previously developed for two-dimensional, low-speed flows, to measure skin friction distributions underneath such flows. This approach required the local flow direction on the surface, and therefore traditional oil flow visualization was coupled with OFI measurements. A cross-correlation-based algorithm was incorporated to extract flow direction from sequences of oil flow visualization images. Photogrammetry was used with both surface oil flow and OFI to ensure proper spatial overlap for the two measurements. Results from this study demonstrate the capability of the approach in a complex, supersonic flow field that contains regions of both separation and reattachment concomitant with a wide range of skin friction values. The skin friction results show excellent homogeneity, standard deviation of 5.1% of the mean, in the undisturbed boundary layer upstream of the interaction and capture well-resolved high shear gradients in the interaction region. A comparison to legacy data from a similar interaction shows matching trends within the developed flow.
关键词： three-dimensional flow,shock boundary-layer interaction,supersonic flow,oil film interferometry,skin friction
更新于2025-09-23 15:22:29
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An analysis of low flow for solar thermal system for water heating
摘要： The mass flow rate in the collector loop of a solar domestic hot water system (SDHW) affects its thermal performance. The initial investment and the operation cost are also affected by the selection of the primary flow. Common design rules state a standard specific flow rate of 50 l/hm2 for most collector models. However, the emergence of electronically commuted motors recommends reviewing the interest of the low flow alternative (7–14 l/hm2) for solar thermal systems. In this paper, the thermal performance of a typical serpentine collector has been measured for different mass flow rates. The resulting performance curves and associated measurement uncertainty bands show only a moderate improvement in performance as the flow rate increases. Once the collector thermal behaviour has been characterized, the whole system is modelled, and the initial investment and operating cost are calculated for two design options: high flow (80 l/hm2) and low flow (20 l/hm2). As expected, the solar fraction is slightly higher for the high flow system (4.6% higher) and the number of hours of operation is lower for this system (4.4% less hours of operation). Considering the lower investment cost of the low flow system, the best thermal behaviour of the high flow system requires near 18 years to amortize the largest investment. If other considerations like embodied energy are accounted for, the common practice in designing SDHW systems should promote low flow.
关键词： Solar thermal simulation,Flat plate collector,Low flow,Variable flow
更新于2025-09-23 15:22:29
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[IEEE 2018 5th International Conference on Systems and Informatics (ICSAI) - Nanjing, China (2018.11.10-2018.11.12)] 2018 5th International Conference on Systems and Informatics (ICSAI) - An Optical Network Flow Control Algorithm Based on Benefit Optimization and Dynamic Path Coefficient
摘要： To avoid the congestion in flow control, this paper proposes an optical network flow control algorithm based on benefit optimization and dynamic path coefficient (BO-DPC). This algorithm adjusts path coefficient in time according to the network information. When the flow of requests can be passed lightly, the metric coefficient should be reduced. Whereas path metric coefficient should be increased. The adjustment can make request flow to a less congestion path. And if there is a congestion coming, the bigger request must be automatically abandoned. It has significant advantage compared with traditional SPF algorithm in the same circumstances, which verifies the applicability and rationality of the algorithm.
关键词： BO-DPC,Flow Control,SPF
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE Life Sciences Conference (LSC) - Montreal, QC, Canada (2018.10.28-2018.10.30)] 2018 IEEE Life Sciences Conference (LSC) - Assay Development and Storage for Fluorescence-Based Lateral Flow Immunoassay
摘要： Point-of-care medical diagnostics can provide efficient, cost-effective medical care, and have the potential to fundamentally change our current approach to global health. There have been substantial efforts in developing lateral flow assays for serologic testing, but most of the existing approaches have limited portability, are expensive, and offer limited analytical sensitivity. In this paper, we demonstrated an assay for the detection of antibodies in plasma to Epstein-Barr Nuclear Antigen-1 (EBNA-1) protein and optimization of the assay including washing and blocking conditions. We also investigated the effect of the storage on the assay strips. Using our optimized conditions, we were able to detect anti-Human Papilloma Virus (HPV)-16 E7 antibodies after three weeks of storage. Our goal is to adapt this system to detect HPV biomarkers for cervical cancers in low and middle-income countries.
关键词： storage,immunoassay,sensitivity,Lateral flow assay,fluorescence,point-of-care
更新于2025-09-23 15:22:29
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Visualizing Interactions of Circulating Tumor Cell and Dendritic Cell in the Blood Circulation Using In Vivo Imaging Flow Cytometry
摘要： Objective: Visualizing cell interactions in blood circulation is of great importance in studies of anticancer immunotherapy or drugs. However, the lack of a suitable imaging system hampers progress in this field. Methods: In this work, we built a dual-channel in vivo imaging flow cytometer to visualize the interactions of circulating tumor cells (CTCs) and dendritic cells (DCs) simultaneously in the bloodstream. Two artificial neural networks were trained to identify blood vessels and cells in the acquired images. Results and Conclusion: Using this technique, single CTCs and CTC clusters were readily distinguished by their morphology. Interactions of CTCs and DCs were identified, while their moving velocities were analyzed. The CTC-DC clusters moved at a slower velocity than that of single CTCs or DCs. This may provide new insights into tumor metastasis and blood rheology. Significance: This in vivo imaging flow cytometry system holds great potential for assessing the efficiency of targeting CTCs with anticancer immune cells or drugs.
关键词： Cell Interaction,Circulating Tumor Cell,In Vivo Imaging Flow Cytometry,Artificial Neural Network,Dendritic Cell
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE 20th International Workshop on Multimedia Signal Processing (MMSP) - Vancouver, BC (2018.8.29-2018.8.31)] 2018 IEEE 20th International Workshop on Multimedia Signal Processing (MMSP) - A Deep Convolutional Network Based Supervised Coarse-to-Fine Algorithm for Optical Flow Measurement
摘要： The measurement of optical flow is an important problem in image processing. There are a number of methods available for optical flow estimation, including traditional variational methods, deep learning based supervised/unsupervised methods. In this work, we propose a deep convolutional network (CNN) based supervised coarse-to-fine approach, which is trained in end-to-end fashion. The proposed method is tested on standard optical flow benchmark datasets including Flying Chairs, MPI Sintel Clean and Final, KITTI. Experimental results show that the proposed framework is able to achieve comparable results to previous approaches with much smaller network architecture.
关键词： spatial-pyramid,deep learning,optical flow
更新于2025-09-23 15:22:29
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Three-dimensional simulations of edge impurity flow obtained by the vacuum ultraviolet emission diagnostics in the Large Helical Device with EMC3-EIRENE
摘要： Edge carbon impurity flow in the stochastic layer of the Large Helical Device (LHD) has been investigated with the three-dimensional (3D) edge transport code EMC3-EIRENE. The simulated synthetic C3+ impurity flow profile from EMC3-EIRENE shows a reasonable agreement with the vacuum ultraviolet (VUV) measurements according to the CIV (1548.20 × 2 ?) Doppler-shift spectrum. The same horizontally outward C3+ impurity flows at the top and bottom edges of the stochastic layer are determined by the 3D magnetic field structure and the parallel C3+ impurity flow velocity. The observed up-down asymmetric structure of the C3+ impurity flow at the top and bottom edges is caused by the vertical displacement of the VUV spectrometer from the midplane. The horizontally outward shift of the magnetic axis position from 3.6 to 3.9 m leads to a change of the C3+ impurity flow direction at the top and bottom edges. For a high upstream plasma density, the transport of the C3+ impurity flow is mainly determined by the background parallel plasma flow, while a reversed C3+ impurity flow is obtained for a low upstream plasma density, due to the expansion of the thermal force dominant regions. The enhanced thermal force leads to a suppression of the impurity screening effect.
关键词： spectrometer,LHD,impurity flow,SOL/divertor plasma
更新于2025-09-23 15:22:29
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[IEEE 2018 Conference on Design and Architectures for Signal and Image Processing (DASIP) - Porto, Portugal (2018.10.10-2018.10.12)] 2018 Conference on Design and Architectures for Signal and Image Processing (DASIP) - Energy and Execution Time Comparison of Optical Flow Algorithms on SIMD and GPU Architectures
摘要： This article presents and compares optimized implementations of two optical flow algorithms on several target boards comprising multi-core SIMD processors and GPUs. The two algorithms are Horn-Schunck (HS) and TV-L1, and have been chosen because they are both well-known, and because of their different computational complexity and accuracy. For both algorithms, we have made parallel optimized SIMD implementations, while HS has also been implemented on GPUs. For each algorithm, the comparison between the different versions and target boards is carried out in a two-dimensional fashion: in terms of computing speed – in order to achieve real-time computation – and in terms of energy consumption since we target embedded systems. The results show that for HS, the GPUs are the most efficient in both dimensions, able to process in real-time performances (25 frames per second) up to 8 Mpix images for 0.35 J per image, against 1.8 Mpix images for 0.24 J per image on CPU. The results also highlight the impact of optimizations on TV-L1: far slower than HS without optimization, it can almost match its performance after optimization on CPU, and can achieve real-time performances with 0.25 J for 1.4 Mpix images. We hope these results will help developers design optical flow embedded systems.
关键词： embedded systems,TV-L1,optical flow,real-time processing,energy consumption,GPU,Horn-Schunck,SIMD
更新于2025-09-23 15:22:29
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[IEEE 2018 Conference on Design and Architectures for Signal and Image Processing (DASIP) - Porto, Portugal (2018.10.10-2018.10.12)] 2018 Conference on Design and Architectures for Signal and Image Processing (DASIP) - Implementation of a Real-Time Image-Based Vibration Detection and Adaptive Filtering on an FPGA
摘要： In this paper, we propose and implement a field-programmable gate array (FPGA) system which extracts a vibration component of a desired frequency band from moving images in real-time, aiming at application to image-based vibration suppression such as microsurgery assistance systems. The technical challenges to this end are two-fold: fast and robust detection of vibration components in given moving images and zero-phase band-pass filtering for a desired frequency band. For the former, we employ a statistical approach using dense optical flow to derive frequency components, and design a custom optical flow computing hardware with the Lucas-Kanade (LK) method. For the latter, we implement a sort of adaptive band-pass filters called a bandlimited multiple Fourier linear combiner (BMFLC), which can recompose input signals as a mixture of sinusoidal signals with multiple frequencies in a band with no phase delay. Both designs are implemented in a deeply pipelined manner on a Xilinx Kintex-7 XC325T FPGA, without using any external memories. Empirical experiments reveal that the proposed system extracts a vibration component of high-frequency tremors in hand motions, while intentional low-frequency motions are successfully filtered out. The system processes VGA moving images at 60 fps, with a delay of less than 1 us for the BMFLC, suggesting effectiveness of the deep pipelined architecture.
关键词： FPGA,optical flow,real-time image processing,adaptive filtering,vibration detection
更新于2025-09-23 15:22:29