background : falls are important causes of mortality and morbidity in urban areas and put a high burden on societies. we investigated patterns of fall traumas and related factors in a referral trauma hospital in tehran, iran. methods: in this routine-data-based study, all documents of fall cases in hazrate-rasool hospital, tehran, iran, during october 2014-2015 were investigated. information on...

Several years ago the authors of the present piece wrote a MONTHLY article [1] describing the velocity dependence of aerodynamic drag. Recently, a science reporter for the Guardian newspaper, who found this reference, solicited our help in writing an article about how a 102-year-old woman from Turin could fall out of a fourth floor window and survive [2]. In particular, the reporter wanted to k...

The purpose of this research was to determine whether a decreased hamstring activation rate among the elderly is responsible for a higher horizontal heel contact velocity and increased likelihood of slip-induced falls compared to their younger counterparts. Twenty-eight subjects from two age groups (14 young and 14 old) walked across a linear walking track with embedded force platforms while we...

Although the energy available during a fall from standing greatly exceeds that required to produce hip fracture, this occurs in only about 2% of falls in the elderly. This is thought to be due in part to one's ability to reduce the vertical impact velocity (nu(nu)) and kinetic energy (KE(nu)) of the body through energy absorption in the lower extremity muscles during descent. The present study ...

PURPOSE: The Coastal and Hydraulics Engineering Technical Note (CHETN) herein describes a method for estimating the percentage of sand-sized material placed in suspension by breaking waves and carried by a cross-channel current to either fall into a navigation channel or travel across it. Required inputs are channel width and depth, depth in the vicinity of the channel, depth-averaged current v...

We investigate decaying D-branes as the origin of the thermal string gas of string gas cosmology. We consider initial configurations of low-dimensional branes and argue that they can time evolve to thermal string gas. We find that there is a range in the weak string coupling and fast brane decay time regimes, where the initial configuration could drive the evolution of the dilaton to values, wh...