Dual-track interest rates and the conduct of monetary policy in China

China has a dual-track interest-rate system: bank deposit and lending rates are regulated while money and bond rates are market-determined. The central bank also imposes an indicative target, which may not be binding at all times, for total credit in the banking system. We develop and calibrate a theoretical model to illustrate the conduct of monetary policy within the framework of dual-track interest rates and a juxtaposition of price- and quantity-based policy instruments. We model the transmission of monetary policy instruments to market interest rates, which, together with the quantitative credit target in the banking system, ultimately are the means by which monetary policy affects the real economy. The model shows that market interest rates are most sensitive to changes in the benchmark deposit interest rates, significantly responsive to changes in the reserve requirements, but not particularly reactive to open market operations. These theoretical results are verified and supported by both linear and GARCH models using daily money and bond market data. Overall, the findings of this study help us to understand why the central bank conducts monetary policy in China the way it does, using a combination of price and quantitative instruments with differing degrees of potency in terms of their influence on the cost of credit.monetary policy; People’s Bank of China; dual-track interest rates; interest rate liberalization

Influence of vitamin D supplementation on immune function of healthy aging people:A pilot randomized controlled trial

Objectives: This study aims to investigate the influence of vitamin D supplementation on immune function of healthy older adults. Materials and methods: Designed as a randomized controlled trial, 21 participants (55–85 years) completed the study during May–November 2018 in Coventry, England. The participants were randomized into vitamin D or the control group, stratified by age, gender and body mass index. The vitamin D group (n = 12) took vitamin D3 tablets of 1,000 IU/day for 12 weeks plus vitamin D education leaflet, while the control group (n = 9) were only provided with the leaflet. At baseline, 6 and 12 weeks, plasma 25(OH)D levels and immunological and metabolic parameters including phagocytic activity of granulocytes and monocytes, tumor necrosis factor, interleukin 6, lymphocyte subsets and fasting blood glucose and lipid were measured. Dietary vitamin D intake was analyzed at baseline and week 12. Data were presented as mean ± SD. Two-way repeated measures ANOVA and independent t-test were used to analyze the data. Results: At baseline, 42.9% of the participants were vitamin D deficiency (25(OH)D 50 nmol/L. Overweight/obese participants (n = 9) had significantly lower mean plasma 25(OH)D concentration (22.3 ± 8.7 nmol/L) than normal weight participants (48.1 ± 34.3 nmol/L) (P = 0.043). There was a significant increase in plasma 25(OH)D concentration in vitamin D group compared with that in control group (P = 0.002) during the intervention period. The plasma 25(OH)D concentration in vitamin D group was increased at 6 weeks (from 38.4 ± 37.0 nmol/L at baseline to 51.0 ± 38.2 nmol/L) with little change observed between 6 and 12 weeks (51.8 ± 36.4 nmol/L). The plasma creatinine concentration in vitamin D group was significantly decreased compared with the control group (P = 0.036) (79.8 ± 7.0 μmol/L at baseline vs 75.1 ± 5.4 μmol/L at week 12). No significant effect of vitamin D supplementation was determined on immunological parameters. Conclusion: Vitamin D deficiency is common among the aging population in the UK even during the summertime. Vitamin D supplementation at 1,000 IU/day for 12 weeks significantly increased plasma 25(OH)D concentration but showed no effect on metabolic and immunological parameters except decreased plasma creatinine

Ageing impairs the T cell response to dendritic cells

Dendritic cells (DCs) are critical in priming adaptive T-cell responses, but the effects of ageing on interactions between DCs and T cells are unclear. This study investigated the influence of ageing on the maturation of and cytokine production by human blood-enriched DCs, and the impact on T cell responses in an allogeneic mixed leucocyte reaction (MLR). DCs from old subjects (65-75y) produced significantly less TNF-α and IFN-γ than young subjects (20-30y) in response to lipopolysaccharide (LPS), but expression of maturation markers and co-stimulatory molecules was preserved. In the MLR, DCs from older subjects induced significantly restricted proliferation of young T cells, activation of CD8+ T cells and expression of IL-12 and IFN-γ in T cells compared with young DCs. T cells from older subjects responded more weakly to DC stimulation compared with young T cells, regardless of whether the DCs were derived from young or older subjects. In conclusion, the capacity of DCs to induce T cell activation is significantly impaired by ageing

Chemical Production of Kopi Luwak

The Civet Cat of family Vivverridae is used to produce a rare coffee product called Kopi Luwak. As a result of Kopi Luwak’s increasing popularity, Civet Cat abuse is prevalent. Our research aims to recreate Kopi Luwak by artificially replicating the conditions of the Civet Cats digestive system. Proteolytic enzymes, acid treatment, and varying incubation conditions will be used to simulate the process

Stability Analysis and Design of Time-Varying Nonlinear Systems Based on Impulsive Fuzzy Model

This paper develops a general analysis and design theory for nonlinear time-varying systems represented by impulsive T-S fuzzy control model, which extends conventional T-S fuzzy model. In the proposed, model impulse is viewed as control input of T-S model, and impulsive distance is the major controller to be designed. Several criteria on general stability, asymptotic stability, and exponential stability are established, and a simple design algorithm is provided with stability of nonlinear time-invariant systems. Finally, the numerical simulation for the predator-prey system with functional response and impulsive effects verify the effectiveness of the proposed methods