As the population increases sharply around the globe, energy resources occur to be a huge shortage. Renewable sources urgently to be developed to satisfy human demands. Unlike the lithium-ion battery’s...

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Background and Objectives: The Chinese population typically has inadequate folate intake and no mandatory folic acid fortification. Methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) are the two key regulatory enzymes in the folate/ homocysteine (Hcy) metabolism. Hcy has been implicated in the pathogenesis of cardiovascular disease. We conducted a meta-analysis to assess whether the MTHFR gene A1298C and the MTRR gene A66G polymorphisms affect Hcy levels in the Chinese population. Methods: This analysis included 13 studies with Hcy levels reported as one of the study measurements. Summary estimates of weighted mean differences and 95% confidence intervals (CIs) were obtained using random-effect models. Results: Overall, there were no significant differences in Hcy concentrations between participants with the MTHFR 1298 CC (12 trials, n = 129), AA (n = 2166; β, −0.51 μmol/L; 95%CI: −2.14, 1.11; P = 0.53), or AC genotype (n = 958; β, 0.55 μmol/L; 95%CI: −0.72, 1.82; P = 0.40). Consistently, compared to those with the MTRR 66 GG genotype (6 trials, n = 156), similar Hcy concentrations were found in participants with the AA (n = 832; β, −0.43 μmol/L; 95%CI: −1.04, 0.17; P = 0.16) or AG (n =743; β, −0.57 μmol/L; 95%CI: −1.46, 0.31; P = 0.21) genotype. Similar results were observed for the dominant and recessive models. Conclusions: Neither the MTHFR A1298C polymorphism nor the MTRR A66G polymorphism affects Hcy levels in the Chinese population.

The problem of estimating 3D velocity for slowly moving target in synthetic aperture radar (SAR) images is addressed. To solve this task, a new scheme based on multi-static SAR is presented. The developed scheme first estimates all values of the Doppler centroid and Doppler frequency rate in multi-static SAR by fractional Fourier transform method. Then, a Doppler frequency rate is used to estimate the cross-range velocity of the moving target. The Doppler centroids are used to estimate the range velocity and height velocity. Simulation results are given to demonstrate the effectiveness of the scheme.

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Conventional differential synthetic aperture radar tomography (D-TomoSAR) can only capture the scatterers’ one-dimensional (1-D) deformation information along the line of sight (LOS) of the synthetic aperture radar (SAR), which means that it cannot retrieve the three-dimensional (3-D) movements of the ground surface. To retrieve the 3-D deformation displacements, several methods have been proposed; the performance is limited due to the insufficient sensitivity for retrieving the North-South motion component. In this paper, an improved D-TomoSAR model is established by introducing the scatterers’ 3-D deformation parameters in slant range, azimuth, and elevation directions into the traditional D-TomoSAR model. The improved D-TomoSAR can be regarded as a multi-component two-dimensional (2-D) polynomial phase signal (PPS). Then, an effective algorithm is proposed to retrieve the 3-D deformation parameters of the ground surface by the 2-D product high-order ambiguity function (PHAF) with the relax (RELAX) algorithm. The estimation performance is investigated and compared with the traditional algorithm. Simulations and experimental results with semi-real data verify the effectiveness of the proposed signal model and algorithm.