Oxygen deprivation is rapidly deleterious for most organisms. However, Caenorhabditis elegans has developed the ability to survive anoxia for at least 48 hours. Mutations in the DAF-2/DAF-16 insulin-like signaling pathway promote such survival. We describe a pathway involving the HYL-2 ceramide synthase that acts independently of DAF-2. Loss of the ceramide synthase gene hyl-2 results in increased sensitivity of C. elegans to anoxia. C. elegans has two ceramide synthases, hyl-1 and hyl-2, that participate in ceramide biogenesis and affect its ability to survive anoxic conditions. In contrast to hyl-2(lf) mutants, hyl-1(lf) mutants are more resistant to anoxia than normal animals. HYL-1 and HYL-2 have complementary specificities for fatty acyl chains. These data indicate that specific ceramides produced by HYL-2 confer resistance to anoxia.

Emerging technologies are increasingly used in an attempt to "enhance the human body and/or mind" beyond the contemporary standards that characterize human beings. Yet, such standards are deeply controversial and it is not an easy task to determine whether the application of a given technology to an individual and its outcome can be defined as a human enhancement or not. Despite much debate on its potential or actual ethical and social impacts, human enhancement is not subject to any consensual definition. This paper proposes a timely and much needed examination of the various definitions found in the literature. We classify these definitions into four main categories: the implicit approach, the therapy-enhancement distinction, the improvement of general human capacities and the increase of well-being. After commenting on these different approaches and their limitations, we propose a definition of human enhancement that focuses on individual perceptions. While acknowledging that a definition that mainly depends on personal and subjective individual perceptions raises many challenges, we suggest that a comprehensive approach to define human enhancement could constitute a useful premise to appropriately address the complexity of the ethical and social issues it generates.

This literature review seeks to examine knowledge dissemination interventions (KDIs) implemented in health research and gauge their effectiveness on three kinds of outcomes: (a) knowledge acquisition, (b) changes in attitudes, and (c) changes in practice. MEDLINE and Cumulative Index to Nursing and Allied Health Literature databases from 2006 to 2011 were searched. Nineteen articles were retrieved. Most of the KDIs that were evaluated had a positive impact on knowledge acquisition and changes in attitudes, but a limited one on practice. KDIs are diverse in terms of knowledge, actors, contexts, and dissemination methods. They cannot be readily applicable to other projects.