Several branches of the potential outcome causal inference literature have discussed merits blocking versus complete randomization. Some concluded it can never hurt precision estimates, and some hurt. In this paper, we reconcile these apparently conflicting views, give a more thorough discussion what guarantees no harm, discuss how other aspects blocked design cost, all in terms precision. We d...

the main diatomic structure-forming species of the zayandehrud reservoir was investigated by collecting samples from the surface, five, seven and 10 m depths from january 2011 to october 2012 along four linear transects. asterionella formosa hassall, cyclotella ocellata pantocsek and fragilaria crotonensis kitton were revealed as the three structure-forming species among diatomic algae in the r...

Background As per the vaccine management policy of the Government of India all vaccine vials opened for an immunization session were discarded at the end of that session, irrespective of the type of vaccine or the number of doses remaining in the vial prior to 2013. Subsequently, open vial policy (OVP) was introduced in 2013 and should reduce both vaccine wastage as well as governmental healthc...

OBJECTIVES To demonstrate why the 'nil per os except medications' order is contraindicated prior to dysphagia testing and to recommend ways to prevent aspiration of medications in the dysphagic population. METHODS A 71-year-old male deemed at-risk for aspiration due to coughing when drinking thin liquids was made nil per os except medications and referred for dysphagia testing. Swallowing was...

Let X be any variety in characteristic zero. V?X an open subset that has toroidal singularities. We show the existence of a canonical desingularization except for V. It is morphism f:Y?X, which does not modify V and transforms into embedding Y, with singularities extending those on Moreover, exceptional divisor simple normal crossings Y. The theorem naturally generalizes Hironaka desingularizat...