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Ocean surface wind and wave information is important in a wide variety of areas, such as coastal disaster reduction, offshore structure design, and atmosphere‐ocean flux estimation. This study proposed a new method for ocean surface wind estimation from surface wave spectrum information measured by small global positioning system buoys. The concept of this method relies on the assumption that the high‐frequency part of the ocean‐wave spectrum is proportional to u∗f−4 ${u}_{\ast }{f}^{-4}$ where u∗ ${u}_{\ast }$ is the friction velocity and f $f$ is the frequency. The determination algorithm for the coefficient of f−4 ${f}^{-4}$ was optimized in this study. The wind direction was determined by the wave cross‐spectrum, assuming that the wind direction aligns the propagation direction of the high‐frequency part of the wave. The proposed wind estimation method was applied to bay and open ocean observations, and the performance of the proposed wind estimation method was similar between the bay and the open ocean. The proposed method improves the wind estimation especially in coastal areas and at high wind speeds in the open ocean compared with the previous method. The performance of the method of the previous study differs between the bay and open ocean due to their spectral shape differences. High‐quality wind and wave information can be obtained using the proposed method. If the mass deployment of small drifting buoys covered the global ocean, the information based on the proposed method could be considerably powerful, and could compensate for the weakness of satellite‐based wind and wave estimations. Plain Language Summary: Ocean observations are spatially sparse compared with on‐land observations because of the difficulty of observation platform development. However, ocean wind and wave information is important in a wide variety of areas, such as coastal disaster mitigation and offshore structure design. Recently, readily deployed small global positioning system (GPS)‐tracked buoys for wave observation have been developed that have the potential to fill gaps in observations through mass deployment. This study proposes a new ocean wind speed and direction estimation method using ocean wave information derived from a small GPS buoy. The performance of the proposed method was validated and compared with data of the observed wind. It was shown that the proposed method can be applied to any type of wave condition, whereas the applicability of the previous method was limited. The proposed method allows for high‐quality ocean wind and wave information to be simultaneously collected. Key Points: Ocean surface wind is estimated from ocean surface wave spectrum information measured by a small global positioning system buoyOcean surface wind is estimated from ocean surface waves for both bay and open ocean conditionsThe newly proposed method improves the accuracy of wind speed and direction estimations from ocean surface waves [ABSTRACT FROM AUTHOR]

Abstract: The authors encountered a patient with gastric varices draining to the IVC not only via the usual route of the left renal vein but also via a circumaortic renal vein. Balloon-occluded retrograde transvenous obliteration (B-RTO) of the gastric varix was performed with balloon occlusion of the circumaortic renal vein and retrograde injection of sclerosing agent (5% of ethanolamine oleate) into the varix. Eradication of the gastric varix was confirmed on endoscopic examination 2 months later. We document the first case of B-RTO performed for gastric varix via the circumaortic renal vein. Details of this rare occurrence and implications for treatment are presented herein. [Copyright &y& Elsevier]

Background: Colonic mucosal lesions observed in patients with portal hypertension have been reported as portal hypertensive colopathy. We studied the rectal mucosa in patients with liver cirrhosis to evaluate the prevalence of mucosal reddening which looks like gastric red spots in the portal hypertensive gastropathy and to determine whether there is a correlation between this lesion and portal hypertension or the severity of liver disease. Methods: Seventy-two patients with liver cirrhosis and 50 control subjects were examined. Colonoscopy was performed to evaluate the presence of mucosal reddening in the rectum. We investigated the relations between rectal mucosal reddening and esophageal varices, portal hypertensive gastropathy and the severity of liver cirrhosis. Results: Rectal mucosal reddening was observed in eight of 72 patients with liver cirrhosis but in none of the 50 control subjects; its prevalence in cirrhosis patients was significantly higher than that in the control subjects (P < 0.05). Cirrhosis patients with esophageal varices were more likely to have rectal mucosal reddening than cirrhosis patients without esophageal varices (P < 0.05). In addition, the occurrence of rectal mucosal reddening correlated with the severity of cirrhosis, based on Child–Pugh's classification (P < 0.05). Conclusion: We have shown that rectal mucosal reddening develops in patients with liver cirrhosis and is associated with the existence of esophageal varices and the severity of liver cirrhosis. These results suggest the possibility that portal hypertension and impaired liver function may play an important role in the pathogenesis of rectal mucosal reddening in patients with cirrhosis. [ABSTRACT FROM AUTHOR]