Crucial Experiment

Trichoepithelioma: A Rare but Crucial Dermatologic Issue

BACKGROUND Trichoepithelioma is a rare benign skin lesion that originates from hair follicles. Trichoepitheliomas are mostly seen in the scalp, nose, forehead, and upper lip. METHODS We present a large family of Iranian origin with 15 individuals affected with multiple familial trichoepithelioma in four generations, and treated with three different methods. RESULTS Trichoepithelioma is his...

From the triangle Sagnac experiment to a practical, crucial experiment of the constancy of the speed of light using atomic clocks on moving objects

According to the triangle Sagnac experiment, between point A and point B that are moving in a circular motion, the travel times for light or radio signals from A to B and from B to A are different. The difference ∆t, i.e. the Sagnac effect, equals 2VDL/c, where D is the foot of the altitude to AB, VD is the speed of point D and L is the distance from A to B. The Sagnac effect exists whether the...

A history of nitrous oxide and oxygen anaesthesia. Part V: The crucial experiment, its eclipse, and its revival.

Animal Rights Consideration is a Necessity in Conducting an Experiment

An Introduction to Natural Experiment Studies

در دو سخن سردبیری شماره‌های قبل به مطالعات مداخله‌ای (Interventional and/or experimental studies) [1] و مطالعات نیمه تجربی (studies Quasi-experiment) [2] پرداختیم. همان جا، به این نکته اشاره کردیم که برای اندازه‌گیری کارآیی یک دارو، واکسن، برنامه بهداشت عمومی و متغیرهای دیگری از این دست، مطالعات مداخله‌ای بهترین گزینه هستند. تقسیم تصادفی و کورسازی از مؤلفه‌های اساسی یک مطالعه مداخله‌ای است [1]....