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BACKGROUND: Diabetes is a chronic disease that can lead to a variety of complications and even cause death. The signal characteristics of the photoplethysmography signals (PPG) and electrocardiogram signals (ECG) can reflect the autonomic and vascular aspects of the effects of diabetes on the body. OBJECTIVE: Based on the complex mechanism of interaction between PPG and ECG, a set of ensemble empirical mode decomposition-independent component analysis (EEMD-ICA) fusion multi-scale percussion entropy index (MSPEI) method was proposed to analyze cardiovascular function in diabetic patients. METHODS: Firstly, the original signal was decomposed into multiple Intrinsic Mode Function (IMFs) by ensemble empirical mode decomposition EEMD, principal components of IMF were extracted by independent component analysis (ICA), then the extracted principal components were reconstructed to eliminate the complex high and low frequency noise of physiological signals. In addition, the MSPEI was calculated for the ECG R-R interval and PPG amplitude sequence.(RRI and Amp) The results showed that, compared with EEMD method, the SNR of EEMD-ICA method increases from 2.1551 to 11.3642, and the root mean square error (RMSE) decreases from 0.0556 to 0.0067. This algorithm can improve the performance of denoising and retain more feature information. The large and small scale entropy of MSPEI (RRI,Amp) was significantly different between healthy and diabetic patients (p < 0.01). RESULTS: Compared with arteriosclerosis index (AI) and multi-scale cross-approximate entropy (MCAE): MSPEISS (RRI,Amp) indicated that diabetes can affect the activity of human autonomic nervous system, while MSPEILS (RRI,Amp) indicated that diabetes can cause or worsen arteriosclerosis. CONCLUSION: Multi-scale Percussion Entropy algorithm has more advantages in analyzing the influence of diabetes on human cardiovascular and autonomic nervous function. [ABSTRACT FROM AUTHOR]

Rice grain size is a complex agronomic trait, controlled by multiple genes. Chromosome segment substitution lines are an effective method for creating natural occurring variations and are as the ideal materials for exploring the complex traits. In this study, a novel rice long-large grain chromosome segment substitution line Z66 was developed. Z66 contained 12 substitution segments from R225 (average substitution length was 3.32 Mb) based on the genetic backgrounds of Nipponbare. Then, 12 QTLs for rice grain size were identified by the secondary F2 population from Nipponbare/Z66, and 5 novel single-segment substitution lines (SSSLs, S1-S5), and 4 novel double-segment substitution lines (DSSLs, D1-D4) harboring target QTL were developed. Among them, 9 QTLs (qGL3, qGL7, qGL10, qGW6, qGW10, qRLW3, qRLW10, qGWT3, and qGWT10) could be verified by the SSSLs, indicating that these QTLs were genetically stable. In addition, 6 novel QTLs (qGL9-2, qGW9-2, qRLW6, qRLW7, qRLW9-2, and qGWT7) were detected by the SSSLs. Among 18 QTLs, 5 QTLs (qGL9-2, qRLW9-1, qRLW9-2, qGW9-2, and qGWT9-2) might be novel. Target QTLs pyramiding showed that the pyramid of different QTLs had various epistasis effects. For example, the pyramids of qRLW3 (a=0.21) and qRLW9-2 (a=0.08) produced an epistasis effect of 0.10, which made the ratio of grain length to width in D2 significantly larger than that in Nipponbare, S1 (qRLW3), and S4 (qRLW9-2). The pyramid of qGWT3 (a=3.99) and qGWT10 (a=3.98) yielded an epistasis effect of -5.35, and its genetic effects in D3 (2.62 g) significantly increased 1000-grain weight of D3 than in Nipponbare, but significantly decreased than that in S1 (qGWT3) and S5 (qGWT10). Understanding the interaction effects between target QTLs can predict the phenotype of futural QTL pyramid genotypes, which is important for intelligent design breeding in rice. [ABSTRACT FROM AUTHOR]

Ring‐opening transformations of donor‐acceptor (D‐A) cyclopropanes enable the rapid assembly of complex molecules. However, the enantioselective formation of chiral quaternary stereocenters using substrates bearing two different acceptors remains a challenge. Herein, we describe the first palladium‐catalyzed highly diastereo‐ and enantioselective (3+2) cycloaddition of vinyl cyclopropanes bearing two different electron‐withdrawing groups, a subset of D‐A cyclopropanes. The key to the success of this reaction is the remote stereoinduction through hydrogen bond from chiral ligands, which thereby addressed the aforementioned challenge. A variety of chiral five‐membered heterocycles were produced in good yields and with high stereoselectivity (up to 99 % yields, 99 : 1 er and >19 : 1 dr). In‐depth mechanistic investigations, including control experiments and theoretical calculations, revealed the origin of the stereoselectivity and the importance of H‐bonding in stereocontrol. [ABSTRACT FROM AUTHOR]