Multispectral Image Super-Resolution via RGB Image Fusion and Radiometric Calibration.

Multispectral imaging is of wide application for its capability in acquiring the spectral information of scenes. Due to hardware limitation, multispectral imaging device usually cannot achieve high-spatial resolution. To address the issue, this paper proposes a multispectral image super-resolution algorithm, referred as SRIF, by fusing the low-resolution multispectral image and the high-resolution (HR) RGB image. It deals with the general circumstance that image intensity is linear to scene radiance for multispectral imaging devices while is nonlinear and unknown for most RGB cameras. The SRIF algorithm first solves the inverse camera response function and a spectral sensitivity function of RGB camera, and establishes the linear relationship between multispectral and RGB images. Then the unknown HR multispectral image is efficiently reconstructed according to the linear image degradation models. Meanwhile, the edge structure of the reconstructed HR multispectral image is kept in accordance with that of the RGB image using a weighted total variation regularizer. The effectiveness of the SRIF algorithm is evaluated on both public datasets and our image set. Experimental results validate that the SRIF algorithm outperforms the state-of-the-arts in terms of both reconstruction accuracy and computational efficiency.

Bidirectional texture function image super-resolution using singular value decomposition.

The bidirectional texture function (BTF) is widely employed to achieve realistic digital reproduction of real-world material appearance. In practice, a BTF measurement device usually does not use high-resolution (HR) cameras in data collection, considering the high equipment cost and huge data space required. The limited image resolution consequently leads to the loss of texture details in BTF data. This paper proposes a fast BTF image super-resolution (SR) algorithm to deal with this issue. The algorithm uses singular value decomposition (SVD) to separate the collected low-resolution (LR) BTF data into intrinsic textures and eigen-apparent bidirectional reflectance distribution functions (eigen-ABRDFs) and then improves the resolution of the intrinsic textures via image SR. The HR BTFs can be finally obtained by fusing the reconstructed HR intrinsic textures with the LR eigen-ABRDFs. Experimental results show that the proposed algorithm outperforms the state-of-the-art single-image SR algorithms in terms of reconstruction accuracy. In addition, thanks to the employment of SVD, the proposed algorithm is computationally efficient and robust to noise corruption.

Fast Multispectral Imaging by Spatial Pixel-Binning and Spectral Unmixing.

Multispectral imaging system is of wide application in relevant fields for its capability in acquiring spectral information of scenes. Its limitation is that, due to the large number of spectral channels, the imaging process can be quite time-consuming when capturing high-resolution (HR) multispectral images. To resolve this limitation, this paper proposes a fast multispectral imaging framework based on the image sensor pixel-binning and spectral unmixing techniques. The framework comprises a fast imaging stage and a computational reconstruction stage. In the imaging stage, only a few spectral images are acquired in HR, while most spectral images are acquired in low resolution (LR). The LR images are captured by applying pixel binning on the image sensor, such that the exposure time can be greatly reduced. In the reconstruction stage, an optimal number of basis spectra are computed and the signal-dependent noise statistics are estimated. Then the unknown HR images are efficiently reconstructed by solving a closed-form cost function that models the spatial and spectral degradations. The effectiveness of the proposed framework is evaluated using real-scene multispectral images. Experimental results validate that, in general, the method outperforms the state of the arts in terms of reconstruction accuracy, with additional 20× or more improvement in computational efficiency.

[Spectrum of gene deletion in 471 children with α-thalassemia].

OBJECTIVE: To study the distribution of common α-thalassemia gene deletion in children. METHODS: Blood cell analysis was performed on children who visited the clinic of the Foshan Women and Children's Hospital. Blood samples (2 mL, EDTA anticoagulant) was collected from children with MCV<82 fl for analysis of α-thalassemia gene using the GAP-PCR method. RESULTS: MCV<82 fl was found in 1341 children. Of the 1341 children, 471 (35.1%) were diagnosed with α-thalassemia. The prevalence of α-thalassemia increased with increasing age. --SEA was a major type of α-thalassemia gene deletion (75.3%), followed by -a3.7 (17.0%) and -a4.2 (7.7%) in the 471 patients. The top three genotypes were --SEA/aa (73.2%), aa/-a3.7 (12.5%) and --SEA/-a3.7 (5.5%). CONCLUSIONS: Genetic testing is necessary for the diagnosis of α-thalassemia in children with MCV<82 fl. --SEA is a common type of α-thalassemia gene deletion, and -SEA/aa is a common gene type of α-thalassemia in the subjects of this study.

[Early warning on measles through the neural networks].

To discuss the effects on early warning of measles, using the neural networks. Based on the available data through monthly and weekly reports on measles from January 1986 to August 2006 in Wuhan city. The modal was developed using the neural networks to predict and analyze the prevalence and incidence of measles. When the dynamic time series modal was established with back propagation (BP) networks consisting of two layers, if p was assigned as 9, the convergence speed was acceptable and the correlation coefficient was equal to 0.85. It was more acceptable for monthly forecasting the specific value, but better for weekly forecasting the classification under probabilistic neural networks (PNN). When data was big enough to serve the purpose, it seemed more feasible for early warning using the two-layer BP networks. However, when data was not enough, then PNN could be used for the purpose of prediction. This method seemed feasible to be used in the system for early warning.

[Multicenter controlled study on transient asthma-stopping action of acupuncture at "Qingchuan point"].

OBJECTIVE: To test and verify the transient therapeutic effect of acupuncture at point "Qingchuan" on bronchial asthma. METHODS: Two hundred cases of bronchial asthma at acute attack stage were divided into a trial group of 100 cases treated with acupuncture at point "Qingchuan" and a control group of 100 cases treated with acupuncture at Dingchuan (EX-B1). RESULTS: The total effective rate was 92.60% and the effect occurred within 42-860 seconds after acupuncture in the trial group, and 81.0% and within 114-126 seconds in the control group, respectively, with very significant differences between the two groups (P < 0.01, P < 0.001). CONCLUSION: Acupuncture at point "Qingchuan" can significantly improve asthmatic state in the patient of bronchial asthma with action of rapidly stopping asthma.

Effect of mixing time on taxoid production using suspension cultures of Taxus chinensis in a centrifugal impeller bioreactor.

The effects of fluid mixing on the cell growth and secondary metabolite production of plant cells were investigated in a low-shear centrifugal impeller bioreactor (CIB) system. Suspension cultures of Taxus chinensis cells producing taxuyunnanine C (Tc), a physiologically active secondary metabolite, were used as a model system for this investigation. The mixing time (t(m)) and volumetric oxygen transfer coefficient (k(L)a) in the bioreactor were characterized at various cell densities and operating conditions. A constant t(m) of 5 s or 10 s was maintained during cultivation by adjusting the impeller agitation speed with no detrimental effect on the cultured cells. A higher cell density, Tc content and total Tc production were obtained under the shorter mixing time of 5 s. The favorable effect of more rapid mixing on Tc production was also confirmed when the Tc accumulation was significantly increased through culture elicitation using 100 microM methyl jasmonate (MJA). The lower Tc production at the longer t(m) of 10 s was mainly attributed to oxygen transfer limitation in the dead zones and larger cell aggregates resulting from poor mixing.