Integrating data types to estimate spatial patterns of avian migration across the Western Hemisphere.

For many avian species, spatial migration patterns remain largely undescribed, especially across hemispheric extents. Recent advancements in tracking technologies and high-resolution species distribution models (i.e.

Migratory patterns and connectivity of two North American grassland bird species.

Effective management and conservation of migratory bird populations require knowledge and incorporation of their movement patterns and space use throughout the annual cycle. To investigate the little-known migratory patterns of two grassland bird species, we deployed 180 light-level geolocators on Grasshopper Sparrows () and 29 Argos-GPS tags on Eastern Meadowlarks () at Konza Prairie, Kansas, USA, and six US Department of Defense (DoD) installations distributed across the species' breeding ranges. We analyzed location data from 34 light-level geolocators and five Argos-GPS tags attached for 1 year to Grasshopper Sparrows and Eastern Meadowlarks, respectively.

High-resolution tide projections reveal extinction threshold in response to sea-level rise.

Sea-level rise will affect coastal species worldwide, but models that aim to predict these effects are typically based on simple measures of sea level that do not capture its inherent complexity, especially variation over timescales shorter than 1 year. Coastal species might be most affected, however, by floods that exceed a critical threshold. The frequency and duration of such floods may be more important to population dynamics than mean measures of sea level.

Habitat availability is a more plausible explanation than insecticide acute toxicity for U.S. grassland bird species declines.

Grassland bird species have experienced substantial declines in North America. These declines have been largely attributed to habitat loss and degradation, especially from agricultural practices and intensification (the habitat-availability hypothesis). A recent analysis of North American Breeding Bird Survey (BBS) "grassland breeding" bird trends reported the surprising conclusion that insecticide acute toxicity was a better correlate of grassland bird declines in North America from 1980-2003 (the insecticide-acute-toxicity hypothesis) than was habitat loss through agricultural intensification.

Occupancy patterns of regionally declining grassland sparrow populations in a forested Pennsylvania landscape.

Organisms can be affected by processes in the surrounding landscape outside the boundary of habitat areas and by local vegetation characteristics. There is substantial interest in understanding how these processes affect populations of grassland birds, which have experienced substantial population declines. Much of our knowledge regarding patterns of occupancy and density stem from prairie systems, whereas relatively little is known regarding how occurrence and abundance of grassland birds vary in reclaimed surface mine grasslands.

A series of heterocyclic inhibitors of phenylalanyl-tRNA synthetases with antibacterial activity.

A series of novel heterocyclic analogues have been synthesized and evaluated for their ability to inhibit phenylalanyl-t-RNA synthetases and act as antibacterial agents. Several analogues have good antibacterial activity against Staphylococcus aureus.

A series of spirocyclic analogues as potent inhibitors of bacterial phenylalanyl-tRNA synthetases.

We have identified a series of spirocyclic furan and pyrrolidine inhibitors of Enterococcus faecalis and Staphylococcus aureus phenylalanyl-tRNA synthetases. The most potent analogue 1b showed IC50=5 nM (E. faecalis PheRS) and IC50=2 nM (S.