The “silent period” is an interval of time following the onset of an intense background during which there is absolute refractoriness to incremental light stimuli. The phenomenon has been reported to occur at all levels of retinal processing in the skate (Dowling and Ripps, 1970, 1971, 1972; Green, Dowling, Siegel and Ripps, 1975), in the ERG of several other elasmobranchs (Hamasaki and Bridges...

The purpose of this research is to study the movements of teachers’ churn rate in the state of Washington over the past 14 years. The research of teachers’ churn rate is an integrative study, with retrospective part and prospective part. Retrospective study includes the analysis of descriptive statistics (level I), statistical inference (level II) and causal inference (level III) (Berk, R.A. (2...