In this paper, we study the recognition complexity of discrete geometric 2gures (rectangles, squares, circles, ellipses) on a retina by diameter-limited and order-restricted perceptrons. We construct a diameter-limited recognition perceptron for the family of rectangles, beginning with local con2gurations, which is di6erent from the one shown by Minsky et al. (Perceptrons: An Introduction to Co...

So much attention is focused on the current HIV/AIDS epidemic in Africa that there is a tendency to overlook the grievous burden of disease from which the peoples of that Continent have suffered for centuries. This paper, based on letters sent in 1953/54 by a young doctor in Sierra Leone to his parents in Scotland, together with extracts from Makeni Hospital records of the same period, provides...

INTRODUCTION Breastfeeding promotion is one of the most important strategies against infant mortality and to control child undernourishment. Despite policies and plans to promote and protect breastfeeding in Colombia, its practice is low and its duration is short. OBJECTIVE To propose an ecology framework to interpret and incorporate contextual, interpersonal, and individual factors associate...

AN INTRODUCTION TO THE PLANT SCIENCES By WILLIAM C. DARRAH, Tutor in the Department of Biology and Research Curator in the Botanical Museum, Harvard University. This book offers a concise, humanistic account, of the nature of the plant kingdom. It is intended for use by students in a half-year or one-semester course in botany or plant biology. Emphasis is placed on these four recent development...

PURPOSE To estimate the doses to the heart and coronary arteries from common breast cancer radiotherapy (RT) regimens used worldwide from the 1950s to the 1990s. METHODS AND MATERIALS Virtual simulation and computed tomography planning were used to reconstruct the megavoltage and electron regimens. Manual planning was used for the orthovoltage and brachytherapy regimens. Several sources of va...

and involvement of the trabecular meshwork for 270 degrees. The visual acuity was “normal OU”. Initial treatment consisted of a multitier approach using intra-arterial, intravitreal, and intracameral melphalan. This was followed by 4 monthly cycles of neoadjuvant systemic carboplatin and etoposide. An anterior chamber recurrence was noted 3.5 months later and further intracameral and intravitre...