131 research outputs found
Development of a Real-time PCR test for porcine group A rotavirus diagnosis
Group A Rotavirus (RVA) is one of the most common causes of diarrhea in humans and several animal species. A SYBR-Green Real-Time polymerase chain reaction (PCR) was developed to diagnose RVA from porcine fecal samples, targeting amplification of a 137-bp fragment of nonstructural protein 5 (NSP5) gene using mRNA of bovine NADH-desidrogenase-5 as exogenous internal control. Sixty-five samples were tested (25 tested positive for conventional PCR and genetic sequencing). The overall agreement (kappa) was 0.843, indicating 'very good' concordance between tests, presenting 100% of relative sensitivity (25+ Real Time PCR/25+ Conventional PCR) and 87.5% of relative sensitivity (35- Real Time PCR/40- Conventional PCR). The results also demonstrated high intra- and inter-assay reproducibility (coefficient of variation ≤1.42%); thus, this method proved to be a fast and sensitive approach for the diagnosis of RVA in pigs
Finite Element Analysis to Determine Stress Concentration Factors of Dragline Tubular Joints
This paper presents a finite element analysis (FEA), by using ANSYS 10.0 (SAS IP Inc 2005), to determine the stress concentration factor (SCF) of the dragline tubular joints. Different load cases, element types, weld sizes and shapes are considered in the analysis. The predicted SCF are compared with the experimental values based on full-size laboratory testing. Finite element (FE) model for the dragline tubular joint consists of the main chord and bracing members with all the attachments like, end plates, load cells, nuts and rods, with concave weld shape and equal weld leg length has been selected to determine SCF. Two layers of 10-node tetrahedral element (SOLID187) and 2 layers of 20-node hexahedral element (SOLID186) have been used in the FE model. The FEA results for all the laboratory test specimens are particularly good when loaded under load case 1 (LC1) and reasonable when loaded under load case 2 (LC2). </jats:p
Experiment Study on Abrasives Performance on Vitrified CBN Wheel
In this paper, accord to effect of CBN abrasives in vitrified wheel, eight kinds CBN abrasives were analyzed for its room performance, microcosmic crystal photographs, high temperature performance and corrosion resistance, by right of single grain pressure-resistant intensity apparatus, SEM and DTA etc advanced apparatus. The test results indicated performance of domestic part single crystal CBN has been reached or exceed overseas same product.</jats:p
Current-induced spin polarization in a spin-polarized two-dimensional electron gas with spin–orbit coupling
Construction of a natural phage antibody library of human anaplastic thyroid carcinoma
Optoacoustic monitoring of real-time lesion formation during radiofrequency catheter ablation.
Current radiofrequency cardiac ablation procedures lack real-time lesion monitoring guidance, limiting the reliability and efficacy of the treatment. The objective of this work is to demonstrate that optoacoustic imaging can be applied to develop a diagnostic technique applicable to radiofrequency ablation for cardiac arrhythmia treatment with the capabilities of real-time monitoring of ablated lesion size and geometry. We demonstrate an optoacoustic imaging method using a 256-detector optoacoustic imaging probe and pulsed-laser illumination in the infrared wavelength range that is applied during radiofrequency ablation in excised porcine myocardial tissue samples. This technique results in images with high contrast between the lesion volume and unablated tissue, and is also capable of capturing time-resolved image sequences that provide information on the lesion development process. The size and geometry of the imaged lesion were shown to be in excellent agreement with the histological examinations. This study demonstrates the first deep-lesion real-time monitoring for radiofrequency ablation generated lesions, and the technique presented here has the potential for providing critical feedback that can significantly impact the outcome of clinical radiofrequency ablation procedures. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only
Three-dimensional optoacoustic monitoring of lesion formation in real time during radiofrequency catheter ablation.
INTRODUCTION: Due to lack of reliable imaging contrast from catheter radiofrequency ablation (RFA) lesions, the vast majority of current procedures rely on indirect indicators of ablation activity, resulting in a significant number of arrhythmia reoccurrences after RFA procedures and the need for repeat surgeries. The objective of this work is to develop an accurate method for on-the-fly assessment of the durability and size of lesions formed during RFA procedures. METHOD AND RESULTS: Radiofrequency catheter ablation on freshly-excised porcine ventricular myocardial tissue was optoacoustically monitored by means of pulsed-laser illumination in the near-infrared spectrum. Lesion formation during ablation was captured at a rate of 10 Hz with a 256-detector optoacoustic imaging probe. Post-ablated samples were imaged using multispectral excitation in the wavelength range 740 nm to 860 nm to determine the lesion contrast spectrum. Tomographic reconstruction was performed to generate three-dimensional images of the lesions, which were compared to photographs depicting the final ablated tissue samples. Video-rate three-dimensional tomographic reconstructions depict formation of the lesion with high contrast and spatial resolution. The size and geometry of the lesion was shown to be in excellent agreement with the histological examinations. The wavelength dependence of the lesion contrast shows a contrast peak near 780 nm. CONCLUSION: Deep-tissue three-dimensional monitoring of RFA lesion generation in real time was demonstrated for the first time in this work. The results suggest the potential of optoacoustic monitoring for providing critical feedback on lesion position and size during radiofrequency catheter ablation, improving safety and efficacy of these treatments
Abstracts of the 6th Annual Scientific Meeting of the Hong Kong Neurosurgical Society 4 December 1999
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