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Physiological liver cell replacement is central to maintaining the organ's high metabolic activity, although its characteristics are difficult to study in humans. Using retrospective 14 C birth dating of cells, we report that human hepatocytes show continuous and lifelong turnover, maintaining the liver a young organ (average age < 3 years ). Hepatocyte renewal is highly dependent on the ploidy level. Diploid hepatocytes show an seven-fold higher annual exchange rate than polyploid hepatocytes. These observations support the view that physiological liver cell renewal in humans is mainly dependent on diploid hepatocytes, whereas polyploid cells are compromised in their ability to divide. Moreover, cellular transitions between these two subpopulations are limited, with minimal contribution to the respective other ploidy class under homeostatic conditions. With these findings, we present a new integrated model of liver cell generation in humans that provides fundamental insights into liver cell turnover dynamics.

Recent research on the dynamics of moral behavior has documented two contrasting phenomena - moral consistency and moral balancing. Moral balancing refers to the phenomenon whereby behaving (un)ethically decreases the likelihood of doing so again at a later time. Moral consistency describes the opposite pattern - engaging in (un)ethical behavior increases the likelihood of doing so later on. Three studies support the hypothesis that individuals' ethical mindset (i.e., outcome-based versus rule-based) moderates the impact of an initial (un)ethical act on the likelihood of behaving ethically in a subsequent occasion. More specifically, an outcome-based mindset facilitates moral balancing and a rule-based mindset facilitates moral consistency.

We study how the main business actor in the Inambari hydropower project in Peru (EGASUR) treats the biodiversity impacts of its planned operations. Selecting the choice of the Environmental Impact Assessment (EIA) as the crucial decision, we complement an analysis of expected business interests with an ethical analysis. The analyses reveal that following prima facie business interests would lead to a “minimalist” EIA, which raises ethical issues both from a consequentialist and a deontological perspective. Based on observations from Peru, we find indicators that ethical issues may indeed have been neglected or denied by EGASUR and that a failure to anticipate and appropriately deal with possibly unethical aspects is underlying some of the increased opposition against the project. We argue that anticipatory ethical analysis can help companies make more sustainable business decisions.