On the Existential Road From Regret to Heroism: Searching for Meaning in Life

We investigated whether regret predicted the motivation to act heroically. In a series of studies, we examined the relationship between regret, search for meaning in life, and heroism motivation. First, Study 1 (a and b) investigated the association between regret and search for meaning in life, considering regret as a whole, action regret, and inaction regret. As expected, regret correlated positively with search for meaning in life. In two additional studies (Study 2 and 3), we examined whether regret predicted heroism motivation and whether this effect was mediated through search for meaning in life. Study 2 confirmed this hypothesis for individual differences in regret, using a correlational design. Study 3 confirmed the hypothesis for temporary experiences of regret, using an experimental design. In addition, in Study 3 we found that heroism motivation was stronger for people with high self-enhancement needs than for those with lower self-enhancement needs. We discuss the relationship between regret and heroism in light of these results and explore their implications.

High fidelity developmental excision of Tec1 transposons and internal eliminated sequences in Euplotes crassus

Following the sexual phase of its life cycle, the hypotrichous ciliate Euplotes crassus transforms a copy of its chromosomal micronucleus into a transcriptionally active macronucleus containing short, linear, gene-sized DNA molecules. Tens of thousands of DNA breakage and joining, or splicing, events occur during macronuclear development. The DNA removed by such events includes transposon-like elements, referred to as Tec1 elements, as well as segments of unique sequence DNA, termed internal eliminated sequences (IESs). Both types of elements are bounded by short direct repeats. In the current study, a polymerase chain reaction (PCR) and DNA sequencing strategy has been used to examine the fidelity of excision of two Tec1 elements and three IESs. In all cases, the vast majority of excision events were found to be precise, with one copy of the terminal direct repeats retained at the empty site in the macronuclear DNA molecule. These results, in combination with previous studies that have characterized the excised DNA elements, indicate that the two products of excision (the free element and the macronuclear DNA molecule) share DNA sequences. This suggests that excision events are initiated by staggered cuts in the chromosomal DNA.