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This study suggests three different designs of the moonpool to reduce the internal flow of the moonpool. The experimental and numerical studies were performed to improve the dillship's operability by the flow reduction in the moonpool. Based on the previous result of model tests in two-dimensional (2D) wave flume, three different moonpool designs were proposed: design-1: combination of forward recess deck, vertical bulkhead and beach-type wave absorber; design-2: a step-type forward recess deck; and design-3: a forward recess deck with beach-type wave absorber. Experimental study was carried out in the Offshore Engineering Basin for 87K compact drillship which was 87,000 Mt as design gross tonnage. To verify the experimental results and clearly understand the internal flow of the drillship's moonpool, numerical study was carried out using Reynolds-averaged Navier-Stokes based computational fluid dynamics (CFD) code. From these studies, it was found that all the proposed designs showed significantly reduced internal flow at resonance frequency compared to the original moonpool design of the target drillship, although the characteristic of internal flow reduction was different for each moonpool design. Additional studies were carried out to obtain the improved moonpool design that is expected to further reduce the internal flow of moonpool through CFD. Based on the results of three moonpool designs, the combined one with the step-type recess deck and the wave absorber presents best performance in the viewpoint of flow reduction in the moonpool. [ABSTRACT FROM AUTHOR]

Recently, drillship moonpools are getting longer and wider for the higher operability. With this trend, violent internal flows are getting more concerned in terms of the safety and operability, which have been reported during the operations even in mild seas. Also, it is well known that the internal flow gives higher resistance during the transit of drillship. In this study, to see the effect of larger damping devices, a series of experimental and numerical study was carried out for the four moonpool designs; the ordinary plain moonpool, the moonpool with a recess deck, the moonpool with an isolated recess deck (island deck), and moonpool with a combination of island deck, splash plates, and wave absorber. From the model tests, it was found that the internal flow of the moonpool was significantly reduced by the application of the wave absorber. In case of the moonpool with the island deck, the sloshing mode oscillations was not observed due to the gap flow between the inner wall of the moonpool and the recess. For the in-depth understanding of the flow behaviors and characteristics, the internal flow of the moonpool has been investigated using Reynolds-averaged Navier-Stokes based computational fluid dynamics (CFD) code. The various moonpool designs were simulated to identify the effect of each device for the internal flow reduction of the moonpool. The CFD analysis results with regular waves, the water surface responses inside moonpool such as the flow pattern and resonance frequency, were compared with model test results and showed reasonably good agreements. [ABSTRACT FROM AUTHOR]

The article discusses a research conducted to examine acyl-homoserine lactones' (AHLs) impact on intestine epithelial cell (IEC-6) proliferation and mucosal permeability. Topics include role of AHLs in quorum sensing process, use of tissues from rat colon to test permeability, and role of homosereine lactones (HSLs) in apoptosis, proliferation and permeability. It also presents graphs and images related to the study.

A diet supplemented with cholic acid (CA), the primary 12 α-hydroxylated bile acid, can induce hepatic lipid accumulation in rats without obesity. This study examined the effects of a CA-supplemented diet on blood pressure (BP). After acclimation, WKAH/HkmSlc rats (3 weeks old) were divided into two groups and fed with a control AIN-93-based diet or a CA-supplemented diet (0.5 g CA/kg) for 13 weeks. The CA diet increased systolic and diastolic BP as well as hepatic lipid concentrations in the rats. No changes were found in the blood sodium concentration. Urinary albumin concentration increased in CA-fed rats. An increase was observed in the hepatic expression of ATP-binding cassette subfamily B member 1B that correlated BPs and urinary albumin concentration accompanied by an increase in portal taurocholic acid concentration. These results suggest that 12α-hydroxylated bile acids are involved in increased BP and albuminuria via alteration of hepatic function. [ABSTRACT FROM AUTHOR]

Propeller cavitation is a dominant source of underwater radiated noise (URN) from shipping, and the appropriate evaluation of propeller noise mitigation measures is important for ecological ship design. In this study, a model test procedure and scaling method to predict the full-scale URN level from hydrodynamic noise sources were introduced. The cavity size based on the empirical vortex model was considered in the proposed scaling method for a quiet cruise condition with isolated tip vortex cavitation. This relation provides information on the equivalent cavitation number for the model test to have the same relative radius as that of the full-scale tip vortex cavitation. The alternative test cavitation number can also be chosen as close as possible to the point that gives the equivalent tip vortex cavity size if sheet cavitation exists in the condition for the equivalent cavity size. In this case, additional noise scaling should be performed using the ratio of the tip vortex cavity radii. The new scaling exponent introduced in this study varies according to the distance from the cavitation inception condition and shows a decreasing trend from the value at the inception condition as the equivalent cavitation number for the model test decreases. The scaled URN levels based on the proposed method showed reasonable agreement with the measurement results of a full-scale ship. Finally, the noise reduction effect of the specially designed wake control fin and propeller was investigated through a comparative model test following the proposed scaling strategy, and significant noise reductions were observed with changes in the design configuration. • A Scaling method for the tip vortex cavitation (TVC) on a marine peopeller was demonstrated. • The Present method is validated by comparing with the full-scale measurements and shows good agreement. • The Proposed methology can provide an important guileline for evaluating the noise level of the full-scale ship propeller. [ABSTRACT FROM AUTHOR]

In this study, a series of model tests were performed to study the relative wave elevation responses around a tension leg platform (TLP) in extreme waves. It is well known that a high relative wave elevation causes a horizontal wave impact or a wave-in-deck impact which can result in a serious damage on both fixed and floating offshore structures. In particular, tension leg platform can be exposed to severe wave-in-deck impact events due to nonlinear wave amplifications inside the multiple columns. Irregular wave tests including the waves of 100-year return periods were carried out at Ocean Engineering Basin of KRISO. Focus is on the nonlinear characteristics of the relative wave elevations. Probability of exceedance as well as time series for relative wave elevation are suggested and discussion is made on the effect of location, wave and current. Also, wave-in-deck events are described based on the model test observations. [ABSTRACT FROM AUTHOR]

BACKGROUND: This study was conducted to determine the early cardiac valvular changes in young male ankylosing spondylitis (AS) patients. METHODS: A total of 70 AS patients on treatment without clinical cardiac symptoms were divided into group I (< 10 years, n = 50) and group II (≥ 10 years, n = 20) depending on their disease duration after first diagnosis. Twenty-five healthy volunteers were selected as control subjects. All the subjects underwent transthoracic and transesophageal echocardiography, electrocardiography, and rheumatologic evaluation for AS patients. RESULTS: The thickness of both the aortic and mitral valve was more increased in AS patients than in controls. Aortic valve thickness over 1.3 mm could predict AS with a sensitivity of 73% and specificity of 76%. The prevalence of aortic valve thickening was higher in the AS group compared to the controls. The prevalence of aortic and mitral regurgitation was very low and there was no difference between the controls and the patients. The aortic valve thickening was related to longer disease duration, high blood pressure, disease activity and inflammatory markers. CONCLUSION: Thickening of the aortic and mitral valve was observed without regurgitation in male AS patients early in the course of their disease without clinical cardiac manifestations. This subclinical change of aorto-mitral valve in early AS should be considered and followed up to determine its prognostic implication and evolution. [ABSTRACT FROM AUTHOR]

Despite recent moderate oil prices, the reduction in fuel oil consumption of voyaging ships has been of great interest. Ships experience additional resistance from wind and waves in actual seas during their voyages, and those added resistance contributes the increase of fuel consumption. The accurate prediction of the added resistance is, therefore, crucial for developing highly energy efficient and low fuel-consuming ships. Ships routinely navigate along pre-determined routes between ports and thus relative heading angle is typically not controlled. Therefore, ships can encounter wind and waves coming from any direction. However, added resistance in oblique direction has less been studied by researchers than that in head seas. To predict the operating performance of ships accurately, more focus should also be given to added resistance in oblique direction. In the present study, the motions and added resistance of an LNG carrier are estimated by experimental investigations and numerical computations. The scaled model ship is towed at a constant forward speed in a square basin and the resistance increase is measured in regular oblique waves. Potential flow method and Reynolds-Averaged Navier-Stokes (RANS) based computational fluid dynamics method are employed to compare the magnitudes of motion and added resistance to those obtained from model test. The global trend of motion responses agrees reasonably at all heading angles between the results from experiments and numerical computations. In regard to the added resistance, however the level of accuracy is less favorable for both numerical methods. The discrepancy is further investigated by checking the relevant parameters in potential method, roll damping and relative phases. The detailed results are discussed and key finding is addressed. In the experimental and numerical investigations, the magnitude in the transfer function of added resistance due to waves is significant at bow quartering seas. In addition, the resistance increase appears to be not negligible even at the following and stern-quartering seas. Therefore, operating efficiency of a ship can be evaluated appropriately when contribution of all heading angles is properly taken into account to the evaluation of added resistance. • Numerical computation are significantly scattered for added resistance in oblique seas. • Potential method is sensitive to choosing the describing coordinate system and double-body potential. • Relative phase difference in motions highly contributes the discrepancy of added resistance. • Added resistance in following and stern-quartering seas are noticeable as comparable to that in bow-quartering sea. [ABSTRACT FROM AUTHOR]

The article discusses a study which aimed to establish whether the signal molecule 3-oxo-C12-HSL-induced death of undifferentiated Caco-2 cells are attenuated by mucin 3 (MUC3) expression. Topics discussed include cell culture of the human colon cancer cell line Caco-2, quantitative real-time polymerase chain reaction (PCR), and the preparation of small interfering RNAs (siRNAs) specific to MUC3.