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Aims: Renal dysfunction in patients with chronic heart failure predicts a poor prognosis. Tolvaptan has a diuretic effect in patients with chronic kidney disease and heart failure without adverse effects on renal function. We aimed to determine the effects of tolvaptan and predictors of worsening renal function in patients with heart failure. Methods and results: This post hoc analysis was a sub‐analysis of a single‐centre prospectively randomized trial on the early and short‐term tolvaptan administration. We enrolled 201 participants with decompensated heart failure between January 2014 and March 2019 (early group, n = 104; age: 79.0 ± 12.8 years; late group, n = 97; age: 80.3 ± 10.8 years). Renal ultrasonography was performed before and after the administration of tolvaptan. Urine output and oral water intake significantly increased during tolvaptan administration. The difference between water intake and urine volume increased during tolvaptan administration. Changes in body weight, blood pressure, heart rate, and estimated glomerular filtration rate (eGFR) in both groups were comparable. The changes in peak‐systolic velocity (PSV), acceleration time (AT) of the renal arteries, and resistance index were comparable. The changes in PSV and end‐diastolic velocity (EDV) of the interlobar arteries increased following tolvaptan administration (Δmax PSV: 0.0 ± 14.8 cm/s before tolvaptan vs. 5.6 ± 15.7 cm/s after tolvaptan, P = 0.002; Δmean PSV: 0.4 ± 12.3 vs. 4.9 ± 12.7 cm/s, P = 0.002; Δmax EDV: −0.2 ± 3.5 vs. 1.4 ± 4.0 cm/s, P = 0.001; Δmean EDV: −0.0 ± 3.1 vs. 1.1 ± 3.4 cm/s, P = 0.003). The renal artery AT was negatively correlated with the eGFR (Δmax AT: beta = −0.2354, P = 0.044; Δmean AT: beta = −0.2477, P = 0.035). Conclusions: Tolvaptan increased the PSV and EDV of the interlobar artery, which may mean tolvaptan increased renal blood flow. The renal artery AT may be a surrogate for worsening renal function. [ABSTRACT FROM AUTHOR]

It is now desirable to establish a technique for long-term prediction of the effects of silane-based impregnation agent on concrete structures exposed to various environments. To meet this requirement, the purpose of this study is set to establish the model to evaluate the effect of a silane-based impregnation agent on the waterproofing properties of cementitious materials based on microscopic mechanisms. Several mortar specimens were prepared with the silane-based impregnation agent, and moisture absorption and evaporation experiments were conducted. The results showed that the application of the agent was shown to effectively inhibit the penetration of moisture into the interior of the cementitious materials. The effect of the silane-based impregnation agent was modeled in a multiscale pore structure model by applying a microscopic water-repellent effect to the pores in which no pore water was present at the time of agent coating. The analysis with proposed model showed that, as in the experiment, the moisture supply was reduced by the application of the agent, whereas the amount of moisture loss remained almost the same with and without the agent. Moreover, the analysis quantitatively showed that the water content can continue to decrease with silane treatments, even under repeated wet-dry conditions.

In Japan, many debris flows and sediment-laden floods cause serious damage to human life and property. Effective measures require high-accuracy reproduction and prediction of runout distance (bed variation reach) via numerical simulations. One possible method to increase the accuracy of numerical simulation results involves reviewing the methods used to evaluate depositing rate for flows that contain many different sizes of sediments. This study performed experiments using an artificial channel and high-speed cameras to identify parameters that govern depositing rate. The channel implemented exhibited a change in slope point; thus, the slope of the upper reach differed from the slope of the lower reach. The experiments showed that the equation representing depositing rate is closely related to flow velocity. Additionally, the equation of depositing rate can be determined if other parameters are consistently considered.