ABSTRACT
The Superfluid High REynolds von Kármán experiment facility exploits the capacities of a high cooling power refrigerator (400 W at 1.8 K) for a large dimension von Kármán flow (inner diameter 0.78 m), which can work with gaseous or subcooled liquid (He-I or He-II) from room temperature down to 1.6 K. The flow is produced between two counter-rotating or co-rotating disks. The large size of the experiment allows exploration of ultra high Reynolds numbers based on Taylor microscale and rms velocity [S. B. Pope, Turbulent Flows (Cambridge University Press, 2000)] (Rλ > 10000) or resolution of the dissipative scale for lower Re. This article presents the design and first performance of this apparatus. Measurements carried out in the first runs of the facility address the global flow behavior: calorimetric measurement of the dissipation, torque and velocity measurements on the two turbines. Moreover first local measurements (micro-Pitot, hot wire, ) have been installed and are presented.
ABSTRACT
BACKGROUND/OBJECTIVES: Seborrheic keratoses are ubiquitous benign epithelial skin tumours. A number of unusual locations have already been reported. We report herein the case of a seborrheic keratosis of the nail bed with typical histological features. METHODS/RESULTS: A 58-year-old man presented with a 1-year-history of longitudinal leukoxanthonychia of the right hallux. Surgical treatment was performed. The diagnosis of typical seborrheic keratosis of the nail bed was made on histological examination. CONCLUSION: To our knowledge, this is the first report of a typical, histologically documented seborrheic keratosis of the nail bed. Therefore, this condition should be added to the differential diagnosis of acquired longitudinal leukoxanthonychia. However, surgical treatment remains necessary to rule out other causes, including squamous cell carcinoma.
