Abstract— Two Pugs and two Miniature Schnauzers with multiple pigmented epidermal nevi were investigated. The four dogs had pigmented cutaneous maculae and plaques. Histopathological evaluation showed papillated or digitated epidermal hyperplasia with hypermelanosis and giant keratohyalin granules in the stratum granulosum. Immunohistochemical staining revealed papillomavirus group‐specific antigen in the skin specimens from all four dogs. Electron microscopic study of the specimens from two dogs revealed numerous round viral particles within the nuclei of the keratinocytes in the upper stratum granulosum. It was suspected that papillomavirus was the etiologic agent of the lesions, and that Pugs and Miniature Schnauzers might be predisposed to infection. These findings indicate this canine dermatosis resembles epidermodysplasia verruciformis (EV) of humans, a rare chronic disease caused by human papillomavirus. The potential for transformation of the lesions to squamous cell carcinoma is also suspected and discussed. Résumé— Deux Carlins et deux Schnauzers nains présentant de multiples naevi épidermiques pigmentés sont examinés. Les quatre chiens présentent des macules et des plaques pigmentées. Les lésions histopathologiques montrent une hyperplasie épidermique papillaire ou digitée avec une hypermélanose et la présence de grains de kératohyaline dans le stratum corneum. Les colorations immunohistochimiques révèlent des antigènes spécifiques du groupe des papillomas virus dans les biopsies des quatre chiens. L'étude ultrastructurale à partir des biopsies de deux chiens montrent de nombreuses particules virales rondes dans les noyaux des kératinocytes des couches supérieures du stratum granulosum. II a été suspecté que le papilloma virus était l'agent causal des lésions et que les Carlins et les Schnauzers nains pouvaient être prédisposés à cette infection. Ces éléments font que cette dermatose observée chez le chien ressemble à l'épidermodysplasie verruciforme de l'homme, une dermatose chronique rare causée par un papilloma virus humain. La potentialité de transformation des lésions en épithélioma spinocellulaire est aussi suspectée et discutée. [Nagata, M., Nanko, H., Moriyama, A., Washizu, T., Ishida, T. Pigmented plaques associated with papilloma virus infection in dogs: Is this epidermodysplasia verruciformis? (Plaques hyperpigmentées associées à une infection à papilloma virus chez le chien: est‐ce épidermodysplasie verruciforme?). Resumen— Se investigó dos perros de raza Pug y dos de raza Schnauzer Miniatura con múltiples nevos epidérmicos pigmentados. Los cuatro perros presentaban máculas y placas cutáneas pigmentadas. El estudio histológico mostró hiperplasia epitelial con papilas y digitaciones, así como hipermelanosis y gránules de queratohialina gigantes en el estrato granuloso. Las tinciones immunohistoquimicas detectaron antígeno grupo‐específico de papilomavirus en las muestras de los cuatro animales. Mediante estudios de microscopía electrónica en muestras de dos de los perros se observaron numero...

Deformation behavior of a liquid droplet impinging onto a metal suiface heated at 400°C is examined by means of high-speed photography. The maximum diameters if the radially flowing thin film at the bottom part of an impinging drop, 2Rmax and 2R bma x> the residence time at the heated suiface, 't c and heat-transmitting suifaces integrated over the residence time, 7T: Joc R ' dt and 7T: Joc R~dt, characteristic to the deformed droplet, are measured with aid qf an analyzer for high-speed cine films , which can be all described as functions of the dimensionless Weber number for droplets of water, ethanol and acetic acid. Results for the water droplet are also correlated with its momentum. It is shown that disintegration behavior upon impingement of droplets can not merely be defined with the W eber number and that liquid viscosity takes little part of the behavior.

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SynopsisDeformation behavior of a liquid droplet impinged on a hot metal surface is studied theoretically. For the thickness of the radial thin-film flow at the bottom part of a deforming droplet, an empirical expression is derived based on our previous experimental data,s'7~ and the previous modelil~ is refined using a modified thickness expression instead of a purely theoretical formula of the thickness of the radial thin film flow. New expressions can evaluate the maximum extent of the radial spread and the time-integral of the heat-transmitting base area. Comparisons with the experimental data sustain the present theory on the deformation characteristics.In general, the deformation behavior of a liquid droplet impinging onto a hot metal surface can be satisfactorily explained, even under extensive conditions, by this model. Previous observationss'7~ exhibiting relationship between the droplet behavior and the Weber number are also discussed in the frame work of the present study.

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