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Abstract: The objective of this research work has been to conduct experimental measurements on a dam break flow over a horizontal dry bed in order to provide a detailed insight, with emphasis on the pressure loads, into the dynamics of the dam break wave impacting a vertical wall downstream the dam. The experimental setup is described in detail, comprising state of the art miniaturized pressure sensors, high sampling rate data acquisition systems and high frame-rate video camera. It is a 1:2 scale of the highly cited (Lee et al., 2002, Journal of Fluids Engineering, 124) article experimental apparatus. Kinematics has been analyzed focusing on the free surface and wave front evolution. Experimental observations regarding liquid height and wave front speed have found to be in agreement with existing literature. This agreement enables the authors, assuming a similar framework, to discuss the measured pressure loads as a consequence of the dam break wave front impacting on the downstream wall. These loads show a substantial variability which has been statistically characterized. The measured quantities have been compared with the scarce available data in the literature, whose consistency is discussed. Measurements have been conducted with two filling heights. Scaling effects for such heights are also analyzed. As a direct result of the present initiative, an extensive set of data for computational tools validation is provided as Supplementary Materials, including pressure signals, wave height measurements and experimental videos. [Copyright &y& Elsevier]

Summary: Background: The detection of melanoma poses a substantial challenge, particularly for primary care providers (PCPs) who may have limited training in discriminating between suspicious and benign melanocytic lesions. The noninvasive optical transfer diagnosis (OTD) method was designed to be used by PCPs in their decision‐making process. Objectives: To assess the potential of the OTD method by developing, training and validating an OTD indication algorithm for automated discrimination between benign melanocytic lesions and malignant lesions, based on a set of 712 lesions. Methods: The authors performed in vivoOTD capture and subsequent analysis of 712 pigmented lesions. Of the lesions, 415 were clinically and dermoscopically benign and 297 were dermoscopically suspicious or equivocal. After image capture, all suspicious or equivocal lesions were biopsied and examined histopathologically. Results: Of the 297 suspicious or equivocal lesions, histopathological findings revealed 80 to be malignant (64 melanomas, 13 basal cell carcinomas and 3 squamous cell carcinomas). OTD misdiagnosed one of the 80 malignant lesions as benign (sensitivity, 99%). OTD specificity was 93% for the dermoscopically benign lesions, 73% for all lesions included in the study and 36% for the clinically suspicious but histopathologically benign lesions. Conclusions: High sensitivity and specificity, as provided by OTD in this preliminary study, would help PCPs reduce the number of referrals for dermatology consultation, excision or biopsy. Further studies are planned for screening patients in a primary care setting, with comparisons of OTD results with biopsy or dermoscopy results. [ABSTRACT FROM AUTHOR]

Summary: The incidence of the type of skin cancer called melanoma is on the rise. The detection of melanoma can be difficult, particularly for clinicians who have limited training (compared to dermatologists who specialize in skin) in telling the difference between normal moles (nevi) and melanomas. The noninvasive optical transfer diagnosis (OTD) method is a technology designed to assist in the screening of lesions (e.g. moles) that might be melanomas. In this study, from the U.S.A., U.K. and Norway, the authors took images using OTD and then analysed 712 pigmented lesions (which could be moles or melanomas). Of them, 415 were harmless, or ‘benign’, and 297 were suspicious when examined by specialists using a magnifier called a dermatoscope. After image capture, all of the suspicious moles were biopsied and the tissue samples were examined under the miscroscope. Of the suspicious lesions, 80 proved to be cancer on biopsy (64 melanomas, and 16 other types of skin cancer). OTD misdiagnosed 1 of the 80 cancerous lesions as benign. If verified in further studies, particularly in actual primary care settings, it is likely that the use of OTD technology could help doctors reduce the number of referrals to dermatologists, excision (surgical removal of the lesion), or biopsy, and reduce costs. Further studies are planned for screening patients in the primary care (e.g. GP) setting, with comparisons of OTD results to the gold standards of pathology or dermoscopy. [ABSTRACT FROM AUTHOR]