A retrospective study of 643 cutaneous horns examined in our department between 1970 and 1989 revealed that 38.9% were derived from malignant or premalignant epidermal lesions, and 61.1% from benign lesions. Four main features were associated with premalignant or malignant histopathological change at the base of a cutaneous horn (base pathology). These were: (i) age--the mean age of the patients whose cutaneous horns showed premalignant or malignant base pathology was 8.9 years greater than the mean age of the patients where base pathology was benign (P less than 0.0005); (ii) sex--males were more likely to develop a cutaneous horn with (pre)malignant base pathology (P less than 0.001); (iii) site--over 70% of all (pre)malignant lesions were found on the nose, pinnae, backs of hands, scalp, forearms and the face; a cutaneous horn found at these sites was 2.1 times more likely to have derived from a (pre)malignant base than from any other part of the body (P less than 0.0001); (iv) geometry of the lesion--lesions with a wide base or a low height-to-base ratio were significantly more likely to show (pre)malignant base pathology. Of those solar keratoses giving rise to cutaneous horns, 8.9% also showed histological evidence of change to squamous cell carcinoma (SCC); this figure was not significantly different from the 6.2% of solar keratoses without horns that showed SCC change during the same period (1970-89).

Copper Sources, Metaldepends on whether regional geologic formation processes have resulted in clearly delineated LI fields, as well as on the num-Prod uction, and Meta 1s Trade i n ber of deposits analyzed. We considered a deposit or mining region to qualify as a Late Postcl assi Mesoa me i ca potential source when the artifact signature fell within the ore field. T o determine

RESUMEN IntroducciónEl desarrollo y uso del bronce en el Area Andina fue un fenómeno del Horizonte Medio. La difundida explotación de menas complejas de cobre, arsénico, estaño y níquel y la producción por vez primera de un rango de bronces a gran escala durante este período, tal vez constituyen una marca tecnológica distintiva de dicho Horizonte.¿Qué significa el término "bronce" y cómo se puede hablar de un "rango de bronces"? Los bronces son aleaciones de cobre con otros metales. Estas aleaciones comparten ciertas propiedades físicas o mecánicas. El "bronce clásico" es la aleación de cobre con estaño y en los Andes se acostumbra asociar el bronce estañífero con el Imperio incaico. Ahora sabemos que el bronce estañífero fue producido mucho más temprano, durante el Horizonte Medio.Además, existen otras aleaciones que son verdaderos bronces: por ejemplo la aleación binaria compuesta de dos metales -cobre y arsénico-llamada "bronce arsenical" y una aleación ternaria y bastante rara, compuesta de tres metales -cobre, arsénico y níquel (Lechtman

This is the accepted version of the paper.This version of the publication may differ from the final published version. Permanent repository link AbstractIn this paper, the information needs of mobile individuals are contrasted with those of their static (desktop) counterparts. The information needs of users of a mobile information system, implemented in an outdoor recreational area, are first investigated in a two-part user needs study, which finds a strong geographic component to their information needs have a strong geographic component. Next, four geographic post-query filters which are described which attempt to meet these needs. These filters are spatial proximity (distance in space), temporal proximity (travel time), speed-heading prediction surfaces (likelihood of visiting locations) and visibility (locations that can be seen). Two of these filters (spatial proximity and speed-heading prediction surfaces) are implemented in a mobile information system are evaluated with users in an outdoor setting. The results of evaluation suggest that information that to which post-query geographical filters have been applied is more relevant than unfiltered information, and that users find information sorted by spatial proximity to be more relevant than that sorted by a prediction surface of likely future locations. The paper closes by suggesting that one of the contributory factors to the failure of location-based services to become widely adopted, could be a neglect of the distinct information needs of mobile individuals.

Two sisters with erythrokeratoderma are described. In the younger sister the clinical appearance corresponded to erythrokeratoderma variabilis (EKV), whereas in the older sister it corresponded to progressive symmetrical erythrokeratoderma (PSEK). Ultrastructural findings in both cases were identical. We suggest that EKV and PSEK are different manifestations of a single condition.