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The movement history of boulders is crucial for the reconstruction of paleo‐tsunamis. We report findings from viscous remanent magnetization studies of the boulders on Tongatapu Island, aiming to reconstruct their reworkings. Two boulders exhibited viscous remanence, whereas two larger boulders lacked viscous components but exhibited stable remanence. Both the viscous and stable components deviated from the geomagnetic field direction. These observations indicate that: (a) the boulders with a viscous component were reworked before the latest event, which could have reworked all boulders, and (b) the magnitude of the latest event was larger than that of an earlier event. The reworked timing indicated that the event occurred between 3,000 years ago and the fifteenth century. The difference in the wave height required to move boulders on the eastern and western coasts suggests that the source of the earlier tsunami was likely an eruption due to volcanoes along the Tonga Ridge. Plain Language Summary: This study explores prehistoric tsunamis on Tongatapu Island by examining large rocks transported during the past tsunamis. Upon analyzing the magnetic records of the rocks, we discovered evidence of multiple rock movements, shedding light on the recurrence and magnitude of past events. Magnetic measurements and previously dated latest movement ages revealed that a tsunami occurred between 3,000 years ago and the fifteenth century. Considering the mobility and immobility of the large rocks and their sizes, the data suggest a smaller paleo‐tsunami magnitude than that of the fifteenth‐century event that transported all the rocks; this expands our understanding of natural hazard history and has implications for assessing tsunami risks in the region. The approach adopted here provides a valuable model for investigating historical natural disasters and their impact on coastal areas, offering insights to enhance global tsunami hazard assessment strategies. Key Points: Viscous remanent magnetization of large boulders indicates multiple reworkings, enhancing our understanding of past tsunamis in TongatapuCombined magnetic records and published radiocarbon ages suggest tsunamis occurred between 3,000 years ago and the fifteenth centuryRemanence and wave height estimates show that the older tsunami was smaller than the fifteenth‐century event, with a possible volcanic source [ABSTRACT FROM AUTHOR]

Objectives: It has been reported that AB070597, which contains amino acids and peptides, may prevent the progression of chronic kidney disease (CKD) in cats. The aim of this study was to evaluate the effect of AB070597 on CKD in International Renal Interest Society (IRIS) stage 2 or 3 cats compared with a placebo. Methods: A prospective, randomised, controlled parallel-group study was conducted on 35 cats with CKD. The cats were randomly allocated to receive 300 mg of AB070597 or placebo for 180 days, and cats were re-examined every 30 days. Changes in the results were compared from baseline to endpoint in each group, and the efficacy of AB070597 in cats with CKD was assessed. Results: A total of 35 cats met the inclusion criteria, of which 20 received AB070597 and 15 received a placebo. Blood urea nitrogen (BUN), creatinine (Cre) and phosphorus levels increased significantly in the placebo group at 180 days compared with those at baseline, 30 days and 60 days, whereas these values were not significantly changed in the AB070597 group during the study period. The IRIS stage was also stable in cats with AB070597 from the baseline to the end of the study, whereas the IRIS stage progressed from stage 2 to stage 3 in 26% of cats with placebo. Body weight did not change significantly in either group. Conclusions and relevance: The administration of AB070597 in cats with CKD may be effective in preventing CKD progression. [ABSTRACT FROM AUTHOR]

Knowledge of the shock remanent magnetization (SRM) property is crucial for interpreting the spatial change in a magnetic anomaly observed over an impact crater. This study conducted two series of impact‐induced SRM acquisition experiments by varying the applied field intensity (0–400 μT) and impact conditions. Systematic remanence measurements of cube‐shaped subsamples cut from shocked basalt containing single‐domain titanomagnetite were conducted to investigate the effects of changes in pressure and temperature on the SRM acquisition. The peak pressure and temperature distributions in the shocked samples were estimated using shock‐physics modeling. SRM intensity was proportional to the applied field intensity of up to 400 μT. SRM intensity data for peak pressure and temperature of up to 8.0 GPa and 530 K, respectively, clearly show that it increases with increasing pressure and decreases with increasing temperature. The SRM has unblocking temperature components up to a Curie temperature of 510 K, and it easily demagnetizes with alternating field demagnetization. The observed SRM properties can be explained by the pressure‐induced microcoercivity reduction and temperature‐induced modification of the blocking curve. Although the remanence acquisition efficiency of the SRM is significantly lower than that of the thermoremanent magnetization (TRM), the magnetic anomaly originating from the SRM distribution in a broader region may show a contribution comparable to that of the impact‐induced TRM distribution in a narrow region. Plain Language Summary: Crustal rocks on terrestrial planets acquire remanent magnetization at the time of an impact event as shock remanence. Magnetic field data observed over impact craters play a key role in reconstructing the magnetic field histories of terrestrial planets. Knowledge of shock remanence is crucial for interpreting the spatial changes in the magnetic field observed over an impact crater. In this study, a suite of shock remanence acquisition and evaluation experiments were conducted to investigate the effects of pressure and temperature changes during shock wave propagation on shock remanence acquisition. The experimentally observed characteristics of shock remanence, such as the stability with respect to thermal and alternating field demagnetization and the systematic intensity changes with respect to pressure and temperature changes, are qualitatively explained by the pressure‐ and temperature‐induced changes in magnetic properties during shock wave propagation. The shock remanence intensity with respect to impact conditions was evaluated using newly obtained experimental data, which enabled us to quantitatively evaluate the shock remanence distributions and their contribution to the magnetic field over impact craters. The shock remanence contribution is estimated to be comparable to that of the impact‐induced thermoremanent magnetization, considering the intensity and volume of these remanences. Key Points: Shock remanence acquisition and evaluation experiments are conducted to evaluate the effects of pressure and temperature changesCharacteristics of shock remanence can be explained by a pressure‐induced microcoercivity reduction and a temperature effect on itContribution of shock remanence to magnetic anomaly over crater is estimated to be comparable with that of impact‐induced thermoremanence [ABSTRACT FROM AUTHOR]