The aerial photographs (APs) acquired by the Istituto Geografico Militare (IGM) in the period of the Italian occupation of Ethiopia (1935Ethiopia ( -1941 have recently been discovered, scanned and organised. Until recently, the oldest APs of the country that were available had been taken in the period [1958][1959][1960][1961][1962][1963][1964]. The APs over Ethiopia in 1935-1941 consist of 8281 assemblages on approx. 50 cm x 20 cm hardboard tiles, each holding a label, one nadir-pointing photograph flanked by two low-oblique photographs and one highoblique photograph. The four APs were exposed simultaneously and were taken across the flight line. The high-oblique photograph is presented alternatively at left and at right. There is approx. 60% overlap between subsequent sets of APs. One of Santoni's glass plate multi-cameras was used, with focal length of 178 mm and with a flight

Approximately 34,000 aerial photographs covering large parts of Ethiopia and dating back to 1935-41 have been recently recovered. These allow investigating environmental dynamics for a past period that until now was only accessible from terrestrial photographs or narratives. As the archive consists of both oblique and vertical aerial photographs that cover rather small areas, methods of image-based modelling were used to orthorectify the images. In this study, 9 vertical and 18 low oblique aerial photographs were processed as an ortho-mosaic, covering an area of 25 km², west of Wukro town in northern Ethiopia. Using 15 control points (derived from Google Earth), a RMSE of 28.5 m in X, 35.4 m in Y was achieved. These values can be viewed as optimal, given the relatively low resolution and poor quality of the imagery, the lack of metadata, the geometric quality of the Google Earth imagery and the recording characteristics. Land use remained largely similar since 1936, with large parts of the land being used as cropland or extensive grazing areas. Most remarkable changes are the strong expansion of the settlements as well as land management improvements. In a larger effort, ortho-mosaics covering large parts of Ethiopia in 1935-41 will be produced.

BackgroundA newborn was diagnosed by echocardiogram with an asymptomatic cardiac mass in the right ventricle after a systolic cardiac murmur was detected at birth.Case presentationNine days after birth, the newborn presented with three syncopal episodes and oxygen desaturation which required resuscitation. The mass induced a complete right ventricular outflow tract obstruction. The presence of a patent foramen oval and a patent ductus arteriosus explained the absence of symptoms at birth. Surgery was rapidly considered since the situation was life threatening. The tumor was successfully resected. The mass was a mature teratoma confirmed by microscopic examination, illustrated by pictures and video.ConclusionsThis case was unique because of the absence of symptoms in the first 9 days of the newborn’s life even though symptoms should have mounted due to the obstruction postpartum. The delay was correlated to the closure of the patent ductus arteriosus. It is recommended that newborns with any cardiac mass be followed up regularly due to hemodynamic changes at birth.Electronic supplementary materialThe online version of this article (10.1186/s13019-019-0874-2) contains supplementary material, which is available to authorized users.