Publications by authors named "Fengrong Sun"

Neonicotinoids are the most widely used insecticides globally, but their rapid metabolism in vertebrates makes diagnosing wildlife exposure challenging. More detailed information on the pattern of imidacloprid metabolites over time could be used to better approximate the timing and level of exposure. Here, we applied recently developed sensitive analytical methods to measure imidacloprid (IMI) parent compound along with an expanded suite of metabolites (5-OH-IMI, IMI-olefin, desnitro-IMI, IMI-urea, 6-chloronicotinic acid, 5-AMCP, 6-OH nicotinic acid) and six other neonicotinoids in adult red-winged blackbirds (Agelaius phoeniceus) that were experimentally exposed to one of two field-realistic concentrations of imidacloprid (0.

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Esophageal squamous cell carcinoma (ESCC) is one of the most common malignancies worldwide. MicroRNA (miRNA)-544 is an important cancer-associated RNA that is downregulated in multiple types of cancer. However, the role of miR-544 in ESCC progression remains unknown.

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Computer-aided diagnosis (CAD) has already been widely used in medical image processing. We recently make another trial to implement convolutional neural network (CNN) on the classification of pulmonary nodules of thoracic CT images. The biggest challenge in medical image classification with the help of CNN is the difficulty of acquiring enough samples, and overfitting is a common problem when there are not enough images for training.

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Background: To facilitate differentiation between normal and abnormal values, it is necessary to correct echocardiographic measurements for physiologic variance induced by age, gender, and body size variables.

Methods: A total of 34 two-dimensional echocardiographic parameters were measured in 1,224 healthy Chinese adults with body mass index < 25.0 kg/m.

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Neonicotinoids are the most widely used class of insecticides in the world, and there are increasing concerns about their effects on non-target organisms. Analytical methods to diagnose exposure to neonicotinoids in wildlife are still very limited, particularly for small animals such as songbirds. Blood can be used as a non-lethal sampling matrix, but the sample volume is limited by body size.

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The reliable analysis of highly toxic hexavalent chromium, Cr(VI), at ultra-trace levels remains challenging, given its easy conversion to non-toxic trivalent chromium. This work demonstrates a novel analytical method to quantify Cr(VI) at low ngL(-1) concentration levels in environmental water samples by using speciated isotope dilution (SID) analysis and double-spiking with Cr(III) and Cr(VI) enriched for different isotopes. Ion chromatography tandem mass spectrometry (IC-MS/MS) was used for the analysis of Cr(VI) as HCrO4(-) → CrO3(-).

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This paper describes an algebraic reconstruction algorithm that uses total variation (TV) regularization for differential phase contrast computed tomography (DPC-CT) using a limited number of views. In order to overcome over-flattening inherent in TV regularization, a two-step reconstruction process is used: we first reconstruct tomographic images of gradient refractive index from differential projections with TV regularization; these images are then used to compute tomographic images of refractive index by solving the Poisson equation. We incorporate TV regularization in the reconstruction process because the distribution of gradient refractive index is much more flattened than the refractive index.

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An extremely compact high voltage peaking capacitor is developed. The capacitor has a pancake structure with a diameter of 315 mm, a thickness of 59 mm, and a mass of 6.1 kg.

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The optimal linear transformation (OLT), an image analysis technique of feature space, was first presented in the field of MRI. This paper proposes a method of extending OLT from MRI to functional MRI (fMRI) to improve the activation-detection performance over conventional approaches of fMRI analysis. In this method, first, ideal hemodynamic response time series for different stimuli were generated by convolving the theoretical hemodynamic response model with the stimulus timing.

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The real-time myocardial contrast echocardiography (RT MCE) is a new echocardiography technology, which allows clinicians to noninvasively evaluate the perfusion of myocardial capillary of patients, using the quantitative analysis of RT MCE. But the accurate analysis requires tracking the position of region of interest (ROI) within the myocardial area, so as to compensate for the translation or rotation offsets, which are due to such uncontrollable factors as heart motion. We used diamond search method and Brox's coarse-to-fine warping optical flow technique for this ROI tracking problem.

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Using the quantitative analysis of real-time myocardial contrast echocardiography (RT MCE), clinicians can assess the myocardial perfusion of patients, noninvasively and accurately. We designed a workstation to assist clinicians to automatically implement the accurate analysis of RT MCE. The workstation can compute some hemodynamic parameters of myocardial microcirculation, e.

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This paper proposes a method of extending the optimal linear transformation (OLT), an image analysis technique of feature space, from magnetic resonance imaging (MRI) to functional magnetic resonance imaging (fMRI) so as to improve the activation detection performance over conventional approaches of fMRI analysis. The method was: (1) ideal hemodynamic responses for different stimuli were generated by convolving the theoretical hemodynamic response model with the stimulus timing, (2) considering the ideal hemodynamic responses as hypothetical signature vectors for different activity patterns of interest, OLT was used to extract the features of fMRI data. The resultant feature space had particular geometric clustering properties.

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Objective: To generate a P19-alphaMHC-EGFP reporter line and induce cardiomyocyte differentiation of this reporter line.

Methods: The P19 cells were transfected with palphaMHC-EGFP, a P19-alphaMHC-EGFP reporter line was obtained after G418 selection and limited dilution of recombinant clones. The reporter line was induced to differentiate into cardiomyocytes which would beat and express green fluorescent protein.

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In this paper is presented the research and development of a new myocardial contrast echocardiography (MCE)-based quantitative analysis system for myocardial microcirculation. The system can measure the values of A, beta, A x beta, A-EER (endo-epi ratio of A), beta-EER and A x beta-EER from the signal intensity of real-time 2-D grayscale images and power Doppler images; it can draw the time-intensity curves to indicate the variation of the intensity of microbubbles scattering in subendocardial layer and subepicardial layer with the varying of myocardial segments; and it can estimate the hemodynamic parameters by nonlinear regression analysis. So the MCE software system has brought the quantitative analysis of real-time MCE to success.

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Vibrio harveyi has been reported to enter into a viable but nonculturable (VBNC) state. Two clinical V. harveyi strains, SF1 and CW2, and the type strain, VIB295(T), were incubated in sterilized seawater at 4 degrees C.

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Transmural redistribution of myocardial blood flow (MBF) is the earliest sign of myocardial ischemia. We aimed to evaluate the ability of real-time myocardial contrast echocardiography (MCE) combined with dipyridamole stress to quantify the transmural gradient of MBF during graded coronary stenosis. Real-time MCE was performed in 14 open-chest dogs at seven experimental stages: baseline; hyperemia induced by 6-min infusion of dipyridamole; 50%, 75% and 90% reduction of hyperemic flow after constriction in each stage for 10 min; reperfusion for 10 min; and subtotal occlusion of the left anterior descending coronary artery (LAD) for 90 min.

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Ostium secundum atrial septal defect (osASD) is one of the most commonly occurring cardiac malformations. Although some embryological pathways have been elucidated, the molecular etiologies of ASD are not fully understood. Previous microarray analysis in our laboratory identified differentially expressed genes between osASD and normal right auricular myocardium.

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Shepp-Logan head phantom is the classical model of simulation computing in Computerized Tomography. This paper proposes a new method--considering 3D Shepp-Logan head phantom as the basic reference model to carry on simulation experiment and algorithms performance evaluating in three-dimension medical image reconstruction field. The paper introduces the design and the implementation of 3D Shepp-Logan head phantom as well the computing of projection data at first, and then describes the simulation process of the three-dimension medical image.

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This article reports a quantitative analysis software system for myocardial contrast echocardiography (MCE). It can measure the signal intensity of grayscale images and power Doppler images, draw the time-intensity curves of variations on the intensity of microbubbles scattering in subendocardial layer and subepicardial layer with the pulsing intervals, and estimate the hemodynamic parameters by nonlinear regression analysis. This system has been applied to a study on 20 healthy volunteers, and the results suggest that the software has the capacity for bringing the quantitative analysis of MCE to success.

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