A Mendelian randomization study on causal effects of 25(OH) vitamin D levels on diabetic nephropathy.

BACKGROUND: Vitamin D supplementation is associated with a lower incidence of diabetic nephropathy (DN); however, whether this association is causative is uncertain. METHODS: We used two-sample Mendelian randomization to examine the causal influence of vitamin D on diabetic nephropathy in 7,751 individuals with type I diabetes-related nephropathy (T1DN) and 9,933 individuals with type II diabetes-related nephropathy (T2DN). Meanwhile, we repeated some previous studies on the influence of KIM-1 (kidney injury molecule 1) and body mass index (BMI) on DN. Additionally, to test the validity of the instruments variable for vitamin D, we conducted two negative controls Mendelian randomization (MR) on breast and prostate cancer, and a positive control MR on multiple sclerosis. RESULTS: Results of the MR analysis showed that there was no causal association between 25(OH)D with the early/later stage of T1DN (early: OR = 0.903, 95%CI: 0.229 to 3.555; later: OR = 1.213, 95%CI: 0.367 to 4.010) and T2DN (early: OR = 0.588, 95%CI: 0.182 to 1.904; later: OR = 0.904, 95%CI: 0.376 to 2.173), nor with the kidney function of patients with diabetes mellitus: eGFRcyea (creatinine-based estimated GFR) (Beta = 0.007, 95%CI: -0.355 to 0.369)) or UACR (urinary albumin creatinine ratio) (Beta = 0.186, 95%CI: -0.961 to 1.333)). CONCLUSIONS: We found no evidence that Vitamin D was causally associated with DN or kidney function in diabetic patients.

Potential of Chinese Yam (Dioscorea polystachya Turczaninow) By-Product as a Feed Additive in Largemouth Bass (Micropterus salmoides): Turning Waste into Valuable Resources.

Chinese yam (Dioscorea polystachya Turczaninow) by-product produced in the water extraction process is commonly directly discarded resulting in a waste of resources and environmental pollution. However, the value of Chinese yam by-product which still contains effective ingredients is far from being fully realized; hence, it has the potential to be a safe and effective feed additive in aquaculture. To investigate the impacts of Chinese yam by-product on growth performance, antioxidant ability, histomorphology, and intestinal microbiota of Micropterus salmoides, juvenile fish (initial weight 13.16 ± 0.05 g) were fed diets supplemented with 0% (control), 0.1% (S1), 0.4% (S2), and 1.6% (S3) of Chinese yam by-product for 60 days. The results showed that no significant difference was found in weight gain, specific growth rate, and survival among all the experimental groups (P > 0.05). Feed conversion ratios of the S1 and S3 groups were significantly lower than those in the control group (P < 0.05). SOD activity of the S3 group and GSH contents of Chinese yam by-product groups were significantly higher than those in the control group (P < 0.05). MDA levels of the S2 and S3 groups were significantly lower than those in the control group and the S1 group (P < 0.05). Besides, Chinese yam by-product could protect liver and intestine health, as well as increase the abundance of beneficial bacteria and decrease the abundance of potential pathogens. This study suggests that Chinese yam by-product has the potential to be used as a functional feed additive in aquaculture, providing a reference for efficient recovery and utilization of by-products from plant sources during processing and culturing high-quality aquatic products.

The effect of controlling person's illegalities on stock price returns: Evidence from Elman neural network model.

Controlling persons are the ultimate decision-makers of listed companies. Their illegalities have impacts on investors' wealth, firm development, and capital market's quality. Against this backdrop, we provide a quantitative analysis of the short-term stock price reaction to the criminal detention announcements of controlling persons throughout 2007-2019. We applied the Elman neural network (ENN) model into the classical event study methodology and demonstrated that the combination of them helps to improve the estimation accuracy of the stock price reaction. The results show that the stock price has a significant negative reaction to the criminal detention announcements of listed companies' controlling persons on the announcement day, and the average reaction level is -6.67%. Additionally, the crisis communication measures of the firms could diminish the negative impact of such mandatory disclosure information on their stock price, but the effect is limited. Finally, the 31 companies in our sample cause a total loss of RMB 21.1 billion in market capitalization on the announcement day alone. The above results indicate that the impact of listed companies' controlling persons on the capital market is tremendous, although the number of this group is small. Our work enriches the listed companies' illegalities research and provides a reference for investors' investment choices and follow-up decision making of regulatory authorities. It also provides some guidance for most of the researchers to further explore the application of data mining techniques in nonlinear problems.

Research on multiple bubbles in China's multi-level stock market.

Financial bubbles have always been a topic of long-term concern for economists. Understanding bubble phenomenon and dating the period of bubbles in real time can provide an early warning diagnosis for financial bubbles and help regulatory authorities to control it and maintain market order. The generalized sup ADF (GSADF) and backward sup ADF (BSADF) tests with flexible window width can effectively detect and date periodically collapsing bubbles in real time. Based on the financial present value model, this paper applies right-tail recursive ADF test to test multiple bubbles in China's multi-level stock market. Unlike the other researches in China, the ratios of the real stock prices' natural logarithm to the real dividends' natural logarithm are used for our testing instead of stock price index. Empirical results show that there are 8 bubbles in the Main-Board Market, 6 bubbles in the Small and Medium Enterprises Board (SMEs), and 4 bubbles in the Growth Enterprise Market (GEM). These bubbles are liquidity-driven and presuppose a loose credit cycle, with the exception of bubbles in 2014-2015. The frequent emergence of bubbles in a short time indicates that China's stock market is still emerging market. In addition, frequent fluctuations imply there is a serious "herd effect" and a lack of monitoring mechanism for bubble risk. This study not only enrich the real-time dynamic research on periodical bubbles of China's stock market, but also provide an empirical reference for investors' investment choices, financial decisions of listed companies and warning mechanism of regulatory authorities.