40 research outputs found
Fluorescent Nanoparticles from Several Commercial Beverages: Their Properties and Potential Application for Bioimaging
The presence of nanoparticles in beverages has raised great concern in terms of potential impacts to consumer health. Herein, carbon dots in beverages kvass, pony malta, pilsner beer, Vivant Storm, and Profit were identified. They were shown to have a strong fluorescence under the excitation of ultraviolet light. The emission peaks shift to longer wavelengths accompanied by a remarkable fluorescence intensity decrease. The carbon dots are in the nanosized range and roughly spherical in appearance. Elemental analysis by X-ray photoelectron spectroscopy demonstrated the composition of Kvass carbon dots to be C 83.17%, O 13.83%, and N 3.00%. No cytotoxicity was found at concentrations up to 20 mg/mL for human tongue squamous carcinoma cells, and they can be directly applied in both carcinoma and onion epidermal cell imaging. This work represents the first report of the carbon dots present in beverages, providing valuable insights into these nanoparticles for future biological imaging
Object-wise joint-classification change detection for remote sensing images based on entropy query-by fuzzy ARTMAP
The pixel-wise post-classification comparison (PCC) method is widely used in remote sensing images change detection. However, it is affected by the significant cumulative error caused by single image classification error. What’s more, the pixel-wise change detection method always produces “salt and pepper” effect. To solve the excessive evaluation of changed types and quantity caused by cumulative error and “salt and pepper” effect, a novel remote sensing image change detection method called entropy query-by fuzzy ARTMAP object-wise joint classification comparison (EQFAM-OBJCC) is presented in this article. Firstly, entropy query-by measurement of active learning is integrated with the fuzzy ARTMAP neural network to choose training samples which contain large amounts of information to improve the classification accuracy. Secondly, joint classification comparison is introduced to obtain the pixel-wise classification results. Finally, the object-wise classification and change detection results are produced by superpixel segmentation method, majority voting rule, and comparison of each superpixels. Experimental results demonstrate the validity of the proposed method. The classification and change detection results show that the proposed method can reduce the cumulative error with an average classification accuracy of 94.12% and a total detection error of 27.03%, and effectively resolve the “salt and pepper” problem. The proposed method was used to monitor the reclamation status of Liaohe estuary wetland via 10 time series remote sensing images from 1987 to 2014
Bifurcation control of in Morris-Lecar neuron model via washout filter with a linear term based on filter-aided dynamic feedback
Comparative Study of Pile Pillared Support and Pile-anchor Retaining in Deep Pit
Support pattern is the most important factor affecting the stability of foundation pit. In order to study the stable state of deep foundation pit, this paper selects pile pillared support and pile-anchor retaining which are high accident rate for comparison, and optimizes the construction scheme combined with the actual deep foundation pit project. The deformation of the supporting structure and the settlement of the foundation pit of Huiquan Square are used to analyze by FLAC3D. The variation range and trend of the internal force of the steel support and the axial force of the anchor cable are analyzed under the different values of the soil layer parameters, such as elastic modulus, cohesion and internal friction angle. The results show that the internal force of pile pillared support is greatly affected by the change of cohesion and the anchor axial force is greatly affected by the change of elastic modulus and internal friction angle. Meanwhile, the influence degree of each soil layer parameter on the internal force of support structure is different, which provides reference suggestions for the selection of support pattern of deep foundation pit
Analysis of the Optimization on Application of Seawater Slurry Ice in Coastal Areas
Cold Storage is a key point of cold chain logistics. In this article, the cooling capacities of water, slurry ice and seawater slurry ice were compared, and results showed that both slurry ice performed better than water. Furthermore, differences between seawater ice and slurry ice were analyzed, and experimental results showed that seawater ice has more advantages as coolant for cold storage in the coastal areas. On the basis of the study, we put forward a new design of high temperature cold storage for coastal areas (inland cities)
A broadband integrated microwave photonic mixer based on balanced photodetection
Abstract An integrated microwave photonic mixer based on silicon photonic platforms is proposed, which consist of a dual-drive Mach–Zehnder modulator and a balanced photodetector. The modulated optical signals from microwave photonic links can be directly demodulated and down-converted to intermediate frequency (IF) signals by the photonic mixer. The converted signal is obtained by conducting off-chip subtraction of the outputs from the balanced photodetector, and subsequent filtering of the high frequency items by an electrical low-pass filter. Benefiting from balanced detection, the conversion gain of the IF signal is improved by 6 dB, and radio frequency leakage and common-mode noise are suppressed significantly. System-level simulations show that the frequency mixing system has a spurious-free dynamic range of 89 dB·Hz2/3, even with deteriorated linearity caused by the two cascaded modulators. The spur suppression ratio of the photonic mixer remains higher than 40 dB when the IF varies from 0.5 to 4 GHz. The electrical-electrical 3 dB bandwidth of frequency conversion is 11 GHz. The integrated frequency mixing approach is quite simple, requiring no extra optical filters or electrical 90° hybrid coupler, which makes the system more stable and with broader bandwidth so that it can meet the potential demand in practical applications. Graphical Abstrac
The correlation of hippocampal T2-mapping with neuropsychology test in patients with Alzheimer's disease.
OBJECTIVES: 1) To deduce T2, the inverse of the transverse relaxation rate (R2), in the hippocampus of healthy adults; 2) to investigate the brain iron deposition in Alzheimer's disease (AD) patients and age-matched healthy controls using T2-values. METHODS: T2-weighted data from the bilateral-hippocampi of ten AD patients and sixty healthy controls were collected at six echo time points using multi-slice multi-echo turbo spin echo (MSME-TSE) imaging on a 3.0 T MR-scanner, followed by the neuropsychological testing. The correlations between T2-values and Mini-Mental State Examination (MMSE) scores were investigated on group-wise basis (covariates in the group-wise analyses: gender, age, side and healthy/AD). RESULTS: There were no significant differences in hippocampal T2-values on intra-gender and inter-gender basis (P > 0.05). Hippocampal T2-values of both sides were similar (right: 85.2±2.4 milliseconds; left: 85.3±2.5 milliseconds). The bilateral hippocampal T2 values correlated moderately with age (right: r = -0.59; left: -0.58; P < 0.001). The AD-group had significantly lower T2-values in the hippocampus when compared to normal controls (P < 0.001) and such low T2-values had a strong positive correlation with the MMSE score (R (2) = 0.97; P < 0.05). CONCLUSION: Patients with AD showed significantly lower T2 values, which can be attributed to the increased iron depositions in the hippocampus. A positive correlation between T2-values and cognition scores suggests that quantitative T2 can be used in the early diagnosis of AD and in the monitoring of the treatment response
Object-wise joint-classification change detection for remote sensing images based on entropy query-by fuzzy ARTMAP
Fluorescent Nanoparticles from Several Commercial Beverages: Their Properties and Potential Application for Bioimaging
The presence of nanoparticles in beverages has raised great concern in terms of potential impacts to consumer health. Herein, carbon dots in beverages kvass, pony malta, pilsner beer, Vivant Storm, and Profit were identified. They were shown to have a strong fluorescence under the excitation of ultraviolet light. The emission peaks shift to longer wavelengths accompanied by a remarkable fluorescence intensity decrease. The carbon dots are in the nanosized range and roughly spherical in appearance. Elemental analysis by X-ray photoelectron spectroscopy demonstrated the composition of Kvass carbon dots to be C 83.17%, O 13.83%, and N 3.00%. No cytotoxicity was found at concentrations up to 20 mg/mL for human tongue squamous carcinoma cells, and they can be directly applied in both carcinoma and onion epidermal cell imaging. This work represents the first report of the carbon dots present in beverages, providing valuable insights into these nanoparticles for future biological imaging.Reprinted with permission from J. Agric. Food Chem., 2015, 63 (38), pp 8527–8533, doi:10.1021/acs.jafc.5b04216. Copyright 2015 American Chemical Society.</p