LH-moment estimation for statistical analysis on the wave crest distributions of a deepwater spar platform model test

The design of fixed and compliant offshore platforms requires the reliable estimation of extreme values with small probabilities of exceedance based on an appropriate probability distribution. The Weibull distribution is commonly utilised for the statistical analysis of wave crests, including near-field wave run-ups. The parameters are estimated empirically from experimental or onsite measurements. In this paper, the data set of wave crests from a Spar model test was statistically analysed by using the method of LH-moments for parameter estimation of the Weibull distribution. The root-mean-square errors (RMSEs) and the error of LH-kurtosis were used to examine the goodness-of-fit. The results for the first four LH-moments, the estimated parameters, and the probability distributions showed that the level of the LH-moments has a significant influence. At higher levels, the estimation results gave a more focused representation of the upper part of the wave crest distributions, which indicates consistency with the intention of the method of LH-moments. The low tail RMSE values of less than 2.5% demonstrated that a Weibull distribution model estimated by using high-level LH-moments can accurately represent the probability distribution of large extreme wave crests for incident waves, wave run-ups, and moon pool waves. Goodness-of-fit test on the basis of comparison of sampling LH-kurtosis and theoretical LH-kurtosis was recommended as a procedure for selecting an optimum level

Multi-body dynamics modelling on a self-propelled pufferfish with its application in AUV

We developed a Computational Fluid Dynamics (CFD) based tool coupled with a Multi-Body Dynamics (MBD) technique to investigate a self-propelled pufferfish motion within a still water environment. The 3D pufferfish model consists of body, caudal, dorsal and anal fins. The locomotion of fish is entirely determined by the computation and fully induced by the oscillation motion of fish fins. The influence of the phase angle difference on the fish swimming behaviour is examined by varying the angle difference between the caudal, dorsal, and anal fins. The swimming displacement, hydrodynamic force and the wake pattern are analysed

Anticancer effects of 7,8-dihydromethysticin in human leukemia cells are mediated via cell-cycle dysregulation, inhibition of cell migration and invasion and targeting JAK/STAT pathway

The main focus of this research work was to study the anticancer properties of 7,8-dihydromethysticin against HL-60 leukemia cells. Investigations were also performed to check its impact on the phases of the cell cycle, cell migration and invasion, JAK/STAT signalling pathway and intracellular mitochondrial membrane potential (MMP) and reactive oxygen species (ROS). Cell proliferation was assessed through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and effects on colony formation were examined via clonogenic assay. Flow cytometry and western blott analysis were performed to investigate the distribution of cell cycle phases. Flow cytometric analysis was performed for the examination of MMP and ROS production. The effect on JAK/STAT signalling pathway was examined through western blot analysis. Results depicted that 7,8-dihydromethysticin induced concentration- as well as time-dependent inhibition of cell proliferation in leukemia HL-60 cells. Clonogenic assay indicated potential suppression in leukemia HL-60 cell colonies. The 7,8-dihydromethysticin molecule also caused cell cycle arrest at G2/M-phase along with concentration-dependent inhibition of cyclin B1, D1 and E. ROS and MMP measurements indicated significant ROS enhancement and MMP suppression with increasing 7,8-dihydromethysticin concentrations. Additionally, 7,8-dihydromethysticin led to remarkable dose-reliant inhibition of cell invasion as well as cell migration. Therefore, 7,8-dihydromethysticin should be considered a valuable candidate for leukemia research and chemoprevention