Selective Acceptorless Dehydrogenation and Hydrogenation by Iridium Catalysts Enabling Facile Interconversion of Glucocorticoids

An iridium­(III) pentamethylcyclopentadienyl catalyst supported by 6,6′-dihydroxy-2,2′-bipyridine displays exquisite selectivity in acceptorless alcohol dehydrogenation of cyclic α,β-unsaturated alcohols over benzylic and aliphatic alcohols under mild aqueous reaction conditions. Hydrogenation of aldehydes and ketones occurs indiscriminately using the same catalyst under hydrogen, although chemoselectivity could be achieved when other potentially reactive carbonyl groups present are sterically inaccessible. This chemistry was demonstrated in the reversible hydrogenation and dehydrogenation of the A ring of glucocorticoids, despite the presence of other alcohol/or carbonyl functionalities in rings C and D. NMR studies suggest that an iridium­(III) hydride species is a key intermediate in both hydrogenation and dehydrogenation processes

Appendix B. The Pearson correlation between covariates used in the analysis of occupancy patterns for Batrachochytrium dendrobatidis.

The Pearson correlation between covariates used in the analysis of occupancy patterns for Batrachochytrium dendrobatidis

Trends in Amphibian Occupancy in the United States

<div><p>Though a third of amphibian species worldwide are thought to be imperiled, existing assessments simply categorize extinction risk, providing little information on the rate of population losses. We conducted the first analysis of the rate of change in the probability that amphibians occupy ponds and other comparable habitat features across the United States. We found that overall occupancy by amphibians declined 3.7% annually from 2002 to 2011. Species that are Red-listed by the International Union for Conservation of Nature (IUCN) declined an average of 11.6% annually. All subsets of data examined had a declining trend including species in the IUCN Least Concern category. This analysis suggests that amphibian declines may be more widespread and severe than previously realized.</p></div

Appendix A. Ratio of the probability of disease occurrence in a finite population ψ[1-(1-p')N], to the probability of disease occurrence in an infinite population, ψ.

Ratio of the probability of disease occurrence in a finite population ψ[1-(1-p')N], to the probability of disease occurrence in an infinite population, ψ