Search

This paper explores empirically the behavior of the Chicago Mercantile Exchange (CME) bitcoin futures contract. The analysis focuses on the time period between the launch of the CME bitcoin futures contract on December 18, 2017, and September 17, 2018. The behavior of the bitcoin spot market and CME futures market is compared and analyzed along several dimensions: price, volatility and liquidity. By comparing the Garman-Klass volatilities of bitcoin spot and futures prices with those of different assets, we find that both the bitcoin spot and futures markets exhibit relatively high volatility compared to other assets. When the ratio of trading volume over open interest is used to measure liquidity, the bitcoin futures market shows a mid-level liquidity. We also find while the exchange margin is set to meet the normal price volatility that can cover the daily price movements within one standard deviation, the brokerage margin for bitcoin futures is set at beyond two standard deviations. Some brokerage firms impose non-margin requirements such as high net account balance and open position limits in addition to regular margins. We conclude that the brokerage firms’ relatively high margin and non-margin requirements impede trading activity such as short-sales and thus, liquidity and efficiency in the bitcoin futures market has been slow to develop. JEL Classification: G1

In this study, we investigated antibacterial activity of natural medicinal plants against inducers of acne vulgaris including Propionibacterium acnes, Pseudomonas aeruginosa, Staphylococcus aureus and Malassezia furfur. Antibacterial activity was screened by using paper disc method from ethanol extracts of about sixty Korean medicinal plants against microorganisms related to acne. Significant antibacterial activities were found in ethanol extracts of five plant resources including Cnidium officinale Makino, Cuscuta australis, Rubus coreanus, Schizandra chinensis and Syzygium aromaticum. Minimum inhibitory concentration (MIC) of five candidate plant samples against P. acnes, P. aeruginosa, S. aureus and M. furfur was measured. The ethanol extract of Syzygium aromaticum was most effective with a MIC of ¤1%. In contrast, Cnidium officinale Makino extract was shown the lowest in antibacterial activity at 1% concentration. Notably, no bacterial growth was found in the extracts of both Schizandra chinensis and Syzygium aromaticum inoculated with either P. acne or M. furfur at two different concentrations of 0.1% and 0.5%. In response to S. aureus, all examined five plant extracts appeared no significant antibacterial activity compared to untreated control and both Schizandra chinensis and Syzygium aromaticum extracts allowed to produce 10 CFU/mL of S. aureus at 24-h post inoculation. MIC of Cnidium officinale Makino ethanol extract was 1% against P. acnes and M. furfur, and 0.5% against P. aeruginosa and S. aureus. MIC of Cuscuta australis ethanol extract against P. acnes, P. aeruginosa, S. aureus and M. furfur were 0.5%, 0.1%, 0.5%, and 1%, respectively. The results strongly suggest that Syzygium aromaticum could be employed as a potential anti-acne agent for preventing acne vulgaris.

Trafficking of viral glycoprotein to the surface of infected-cells results in syncytium formation in Newcastle disease virus (NDV)-infected baby hamster kidney (BHK) cells. Hydnellum concrescens, known as a medicinal mushroom, inhibited not only syncytium formation, but also trafficking of glycoprotein, hemagglutinin-neuramidase (HN) to the cell-surface. Viral glycoprotein is processed within the endoplasmic reticulum during routing into surface. Fungal extracts showed inhibitory activities (IC50 15µg/ml) against α-glucosidase. This suggested that H. concrescens extracts inhibited the cell-surface expression of NDV-HN glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.Key words: α-Glucosidase inhibitor, Hydnellum concrescens, trafficking inhibitor.