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We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center., We herein report an efficient method to synthesize cyclic hydroxy ketones with a chiral quaternary center. Catalyzed by an Ir/f-ampha complex, cyclic α,α-disubstituted 1,3-diketones were hydrogenated, giving mono-reduced products with both high enantioselectivities and diastereoselectivities. In addition, C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 C and C 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 C bonds could survive in this catalytic system. This method was applied in the preparation of (+)-estrone. No diols were observed in this chemical transformation. The enantiomeric and diastereomeric induction were achieved as a result of steric hindrance.

Background: Numerous studies have investigated the associations between Vitamin D receptor (VDR) gene polymorphisms and risk of intervertebral disc degeneration but the results remain controversial. This study aimed to drive a more precise estimation of association between VDR gene polymorphisms and risk of intervertebral disc degeneration. Methods: PubMed, EMBASE, Cochrane library, Web of Science and China Knowledge Resource Integrated Database for papers on VDR gene polymorphisms and risk of intervertebral disc degeneration were searched. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association in the homozygote model, heterozygote model, dominant model, recessive model and an additive model. Results: Overall, 23 articles were included in the final meta-analysis. The subgroup analyses by ethnicity showed a significant association of VDR FokI mutation with disc degeneration risk in Caucasians (recessive model, OR with 95%CI 1.301, [1.041, 1.626]; additive model, OR with 95%CI 1.119, [1.006, 1.245]). The results of subgroup analyses by ethnicity showed a significant association of VDR TaqI mutation with disc degeneration risk in Asians but not in Caucasians. There was a significant association between VDR ApaI mutation and risk of disc degeneration and subgroup analyses by ethnicity showed a significant association in Caucasians and in Asians. Conclusions: In summary, VDR FokI polymorphisms was associated with disc degeneration risk among Caucasians but not Asians, VDR TaqI polymorphisms was associated with disc degeneration risk among Asians but not Caucasians, while VDR ApaI polymorphism was associated with disc degeneration risk among Asians and Caucasians.

Recently, increasing attention has been paid to the application of artificial intelligence (AI) to the diagnosis of diverse hepatic diseases, which comprises traditional machine learning and deep learning. Recent studies have shown the possible value of AI based data mining in predicting the incidence of hepatitis, classifying the different stages of hepatitis, diagnosing or screening for hepatitis, forecasting the progression of hepatitis, and predicting response to antiviral drugs in chronic hepatitis C patients. More importantly, AI based on radiology has been proven to be useful in predicting hepatitis and liver fibrosis as well as grading hepatocellular carcinoma (HCC) and differentiating it from benign liver tumors. It can predict the risk of vascular invasion of HCC, the risk of hepatic encephalopathy secondary to hepatitis B related cirrhosis, and the risk of liver failure after hepatectomy in HCC patients. In this review, we summarize the application of AI in hepatitis, and identify the challenges and future perspectives.

In order to improve the transmission rate and security of multi-user differential chaos shift keying (DCSK) systems, a multi-user high rate security DCSK (MHS-DCSK) based on short reference is proposed. The proposed scheme uses a scrambling matrix and a shift matrix to construct a set of scrambling matrices. These scrambling matrices not only enhances the security of the multi-user short reference system but also increases the bit rate. The proposed scheme employs the correlation properties of chaotic sequences to cancel the multi-user interference (MUI). The simulation results show the effectiveness of the proposed scheme.

To improve the antifading and inter-code interference ability of the noncoherent chaotic communication system, a multiuser multicarrier chaotic differential communication system based on a cooperative model is proposed. A single relay of the decode-and-forward type is investigated according to the conventional cooperation protocol. Independent three path Rayleigh channels are considered, and the bit error rate and outage probability are derived and verified via simulations. Numerical and Monte Carlo simulations show that the proposed model can effectively deter fading and inter-code interference effectively.

Hucho bleekeri, also called Sichuan taimen, is a species endemic to Yangtze River drainage in China. Due to habitat destruction, heavy fishing and pollution, the wild population of H. bleekeri has declined rapidly in recent years. Insufficient molecular markers have limited the effective conservation of this species. In the present study, 34 novel single nucleotide polymorphism (SNP) markers were developed in H. bleekeri based on restriction site-associated DNA sequencing (RAD-seq). The minor allele frequency ranged from 0.059 to 0.486, and the observed and expected heterozygosities ranged from 0.118 to 0.861 and 0.112 to 0.507, respectively. Polymorphic information content ranged from 0.105 to 0.375. Among these SNPs, four loci showed significant departures from the Hardy–Weinberg equilibrium (P