PREDICTORS OF ELECTORAL TURNOUT: AN INTERNATIONAL COMPARISON *

Voter turnout in the United States is much lower than in almost all other democratic countries. This has been interpreted as a symptom of popular alienation from the political system, suspicion of politicians, and pessimism about the consequences of political activity. When these perspectives are measured directly, however, it is clear that Americans score very low on almost every item. Indeed, there is no relationship between political con- tentment and turnout. Turnout does not reflect international variations in acceptance of politicians or the political system. Rather, it responds to variations in the bureaucratic steps required to cast a ballot. The United States is one of a handful of countries that require a separate step-registra- tion-before the citizen can vote; and with the partial exception of France it is the only country in which the individual rather than the state bears the responsibility for registration. Copyright 1990 by The Policy Studies Organization.

Metabolic plasticity during transition to naïve-like pluripotency in canine embryo-derived stem cells

Pluripotent stem cells (PSCs) have been described in naïve or primed pluripotent states. Domestic dogs are useful translational models in regenerative medicine, but their embryonic stem cells (cESCs) remain narrowly investigated. Primed-like cESCs expanded in the presence of leukemia inhibitory factor and fibroblast growth factor 2 (LIF-FGF2) acquire features of naïve pluripotency when exposed to chemical inhibitors and LIF (2iL). However, proliferation of cESCs is influenced by the pluripotent state and is comparatively slower than human or mouse PSCs. We propose that different metabolic pathway activities support ATP generation and biomass accumulation necessary for LIF-FGF2 and 2iL cESC proliferation. We found that 2iL cESCs have greater respiratory capacity, altered mitochondrial chain complex stoichiometry and elevated mitochondrial polarization state. Yet, 2iL-enriched cESCs exhibited immature ultrastructure, including previously unrecognized changes to cristae organization. Enhanced ATP level in 2iL cESCs is associated with altered retrograde signalling, whereas LIF-FGF2 cESCs exhibit a lipogenic phenotype. Inhibition of oxidative phosphorylation impaired proliferation and ATP production in 2iL cESCs but not LIF-FGF2 cESCs, which remained sensitive to glycolysis inhibition. Our study reveals distinct bioenergetic mechanisms contributing to steady-state expansion of distinct canine pluripotent states that can be exploited to improve derivation and culture of canine PSCs. Keywords: Embryonic stem cell, Pluripotent stem cell, Naïve pluripotency, Canine, Oxidative phosphorylation, Mitochondri