Anthropogenic modification of forests means only 40% of remaining forests have high ecosystem integrity.

Many global environmental agendas, including halting biodiversity loss, reversing land degradation, and limiting climate change, depend upon retaining forests with high ecological integrity, yet the scale and degree of forest modification remain poorly quantified and mapped. By integrating data on observed and inferred human pressures and an index of lost connectivity, we generate a globally consistent, continuous index of forest condition as determined by the degree of anthropogenic modification. Globally, only 17.4 million km2 of forest (40.5%) has high landscape-level integrity (mostly found in Canada, Russia, the Amazon, Central Africa, and New Guinea) and only 27% of this area is found in nationally designated protected areas. Of the forest inside protected areas, only 56% has high landscape-level integrity. Ambitious policies that prioritize the retention of forest integrity, especially in the most intact areas, are now urgently needed alongside current efforts aimed at halting deforestation and restoring the integrity of forests globally.

Air ventilation by recoil aspiration in polypterid fishes.

High-speed x-ray cine films synchronized with intra-pleuroperitoneal pressure measurements show that polypterid fishes aspiration breathe by the deformation and recoil of their bony-scaled integument. Paleozoic amphibians arose from ancient air-breathing fishes and retained piscine bony scales in V-shaped rows along the belly. These scales resemble those of modern polypterid fishes and may have contributed to inhalation by elastic recoil. The discovery that polypterid fishes breathe by recoil aspiration is the first evidence for aspiration breathing in any lower vertebrate. The use of recoil aspiration by polypterids shows that elastic storage in a stiff body wall can contribute to inhalation in animals with limited capacity for active aspiration.

Conformational transition of poly(alpha-L-glutamic acid). A polyelectrolytic approach.

The charge-induced conformational transition of poly(alpha-L-glutamic acid) (PLGA) is considered in this paper from the point of view of proton dissociation. Equations for the excess electrostatic Gibbs energy of dissociation (i.e., delta pKa) are derived as a function of the degree of ionization, alpha. These analytical equations are used to describe some experimental dissociation curves at different polymer and salt concentrations. The dependence of the calculated delta pKa with respect to the ionic strength for the two conformational states, alpha-helical and extended coil, respectively, is rather satisfactorily explained. Even more interesting are the predictions which are derived from this approach for the transition point, alpha tr which is found to be ionic-strength dependent, in full agreement with the experimental results.