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Cryogens, such as liquid hydrogen and oxygen, are used for future space explorations, which require long-term storage in a closed tank. During long-term storage of cryogens in the tank, thermal stratification is formed near the liquid surface due to heat flow into the tank from the surrounding environment. Therefore, boiloff gas is generated from the surface, which increases the pressure in the tank. An effective way to reduce boiloff gas is to destroy the temperature stratification by mixing cold jet issuing from the bottom of the tank. In this paper, drop tower experiments are conducted to investigate the detailed jet behavior, especially jet's flow pattern and jet-tip height in microgravity. In the experiment, deionized water, which blends red food coloring, was used, and the mixing jet behavior was observed using a Charge Coupled Device (CCD) camera. The jet-flow pattern was investigated under various experimental conditions. Consequently, six flow patterns, including distinctive flow patterns obtained only in microgravity, were observed, and the predicted model for jet-tip height proposed by the authors in submitted paper agrees considerably with the microgravity experimental data within the Mean Absolute Error (MAE) 4.37 mm. [ABSTRACT FROM AUTHOR]

Optimizing diagnostic criteria to detect specific patients likely to benefit from anticoagulants is warranted. A cutoff of 5 points for the International Society on Thrombosis and Haemostasis overt disseminated intravascular coagulation (DIC) scoring system was determined in the original article, but its validity was not evaluated. This study aimed to explore the optimal cutoff points of DIC scoring systems and evaluate the effectiveness of early intervention with anticoagulants. We used a nationwide retrospective registry of consecutive adult patients with sepsis in Japan to develop simulated survival data, assuming anticoagulants were conducted strictly according to each cutoff point. Estimated treatment effects of anticoagulants for in-hospital mortality and risk of bleeding were calculated by logistic regression analysis with inverse probability of treatment weighting using propensity scoring. Of 2663 patients with sepsis, 1247 patients received anticoagulants and 1416 none. The simulation model showed no increase in estimated mortality between 0 and 3 cutoff points, whereas at -4 cutoff points, mortality increased linearly. The estimated bleeding tended to decrease in accordance with the increase in cutoff points. The optimal cutoff for determining anticoagulant therapy may be 3 points to minimize nonsurvival with acceptable bleeding complications. The findings of the present study suggested a beneficial association of early intervention with anticoagulant therapy and mortality in the patients with sepsis-induced DIC. Present cutoff points of DIC scoring systems may be suboptimal for determining the start of anticoagulant therapy and delay its initiation. [ABSTRACT FROM AUTHOR]

Background: Little evidence supports anticoagulant therapy as effective adjuvant therapy to reduce mortality overall in sepsis. However, several studies suggest that anticoagulant therapy may reduce mortality in specific patients. This study aimed to identify a subset of patients with high benefit profiles for anticoagulant therapy against sepsis.Methods: This post hoc subgroup analysis of a nationwide multicentre retrospective registry was conducted in 42 intensive care units in Japan. Consecutive adult patients with sepsis were included. Treatment effects of anticoagulants, e.g. antithrombin, recombinant thrombomodulin, heparin, and protease inhibitors, were evaluated by stratifying patients according to disseminated intravascular coagulation (DIC) and Sequential Organ Failure Assessment (SOFA) score. Intervention effects of anticoagulant therapy on in-hospital mortality and bleeding complications were analysed using Cox regression analysis stratified by propensity scores.Results: Participants comprised 2663 consecutive patients with sepsis; 1247 patients received anticoagulants and 1416 received none. After adjustment for imbalances, anticoagulant administration was significantly associated with reduced mortality only in subsets of patients diagnosed with DIC, whereas similar mortality rates were observed in non-DIC subsets with anticoagulant therapy. Favourable associations between anticoagulant therapy and mortality were observed only in the high-risk subset (SOFA score 13-17; adjusted hazard ratio 0.601; 95 % confidence interval 0.451, 0.800) but not in the subsets of patients with sepsis with low to moderate risk. Although the differences were not statistically significant, there was a consistent tendency towards an increase in bleeding-related transfusions in all SOFA score subsets.Conclusions: The analysis of this large database indicates anticoagulant therapy may be associated with a survival benefit in patients with sepsis-induced coagulopathy and/or very severe disease.Trial Registration: University Hospital Medical Information Network Clinical Trial Registry (UMIN-CTR ID: UMIN000012543 ). Registered on 10 December 2013. [ABSTRACT FROM AUTHOR]

Cavitation may cause a severe damage to rocket engine turbo-pump, and appropriate handling of cavitation is one of the key technologies for rocket engine development. Numerical simulation is quite useful technique, however, simulation result strongly relies on cavitation model. Cavitation flow is essentially strong unsteady and multi scale phenomena, scales of bubbles vary in size from small to large. Therefore, prediction of cavitation by numerical simulation is difficult. Many cavitation models have been proposed and researched. However, direct interface tracking approach has not been applied to cavitating flow and the model characteristic is not fully understood. This research shows direct interface tracking method can properly capture both cloud cavitation and super cavitation and grid resolution affects lift coefficient. [ABSTRACT FROM AUTHOR]