background: rhipicephalus sanguineus and hyalomma marginatum are the most common spe­cies in sheep herds in northeast of iran. there is preliminary evidence that these species may be the vectors of babesia ovis in iran. we carried out two experiments in mashhad area, khorasan razavi province to determine whether b. ovis could be transovarially transmitted by r. san­guineus and h. marginatum . m...

abstract: a continuously variable transmission (cvt) is a transmission which may change step less by way of an infinite variety of effective gear ratios between maximum and minimum values. this contrasts with different mechanical transmissions that solely permit just a few different distinct gear ratios to be selected. continuously variable transmissions (cvts) are mechanical devices that allow...

The special variable ratio transmission characteristics and complex tooth profile curve of elliptic gears make it difficult to analyse their characteristics, which restrict the application development elliptical gears. Given that, a characteristic analysis method based on testing is proposed in this paper. By building high-precision gear test rig, distribution laws dynamic lost motion, static b...

The opportunity arose in 1942 of obtaining certain adult volunteers for an experiment on the transmission of rheumatic fever in blood. This experiment will be recorded in full, although it is realized that owing to its limited scope it is not of great scientific value. It is, however, believed to be the only one of its type on record, and it is therefore of interest and seems to give experiment...