Chronic Giardia intestinalis infection presenting with clinical features mimicking lichen planus.

Sir, Human giardiasis, caused by Giardia intestinalis, a agellate protozoan parasite that colonizes the small bowel, is a worldwide infection (1). Giardia infection is usually asymptomatic but intestinal illness may occur (2–5). Several reports describe the association of allergy with increased levels of total serum IgE antibodies and of speci c IgE antibodies against food allergens in patients aVected by giardiasis, and Giardia infection may determine altered absorption of food antigens causing allergic sensitization (6). Cutaneous signs may be virtually indistinguishable from those of atopic dermatitis (7, 8). Acute reactions such as urticaria or asthma have also been described (9–11). We here report a patient aVected by giardiasis, with lichen-planus-like lesions as the sole clinical feature

Simulink Models for the Prediction of Electromagnetic Transients in DC Traction Systems

This paper is aimed to present a model, implemented through the Simulink software of Matlab, designed to simulate the behavior of the high-speed circuit breaker during the process of extinguishing a short-circuit current in DC power supply systems. In addition, the representative models of an electrical substation, of the contact line and of the track are presented, to apply the circuit-breaker model for the extinction of short-circuit phenomena at certain points of the power supply system of a railway line or trolleybus