This paper argues that banks must be sufficiently levered to have first-best incentives to make new risky loans. This result, which is at odds with the notion that leverage invariably leads to excessive risk taking, derives from two key premises that focus squarely on the role of banks as informed lenders. First, banks finance projects that they do not own, which implies that they cannot extrac...

Palaeoenvironmental research in the Southern Levant presents a series of challenges, partly due to the unequal distribution of palaeoenvironmental records and potential archives throughout the region. Our knowledge of climatic evolution, during the last approximately 25,000 years, is of crucial importance to understand cultural developments. More local, well-dated, multi-proxy studies are much ...

Supraglacial deposits are known for their influence on glacier ablation. The magnitude of this influence depends on the thickness and the type of the deposited material. The effects of thin layers of atmospheric black carbon and of thick moraine debris have been intensively studied. Studies related to regional-scale deposits of volcanic tephra with thicknesses varying between millimetres and me...

The Atacama Desert, northern Chile, is one of the driest deserts on Earth and, as such, a natural laboratory to explore the limits of life and the strategies evolved by microorganisms to adapt to extreme environments. Here we report the exceptional adaptation strategies of chlorophototrophic and eukaryotic algae, and chlorophototrophic and prokaryotic cyanobacteria to the hyperarid and extremel...

Localized tephra deposition in marine sequences is the product of many complex primary and secondary depositional processes. These can significantly influence the potential applicability of tephra deposits as isochronous marker horizons and current techniques, used in isolation, may be insufficient to fully unravel these processes. Here we demonstrate the innovative application of X-ray microto...

Measuring value and interest rate risk in retail financial markets such as the market for consumer deposits has proven to be a very difficult problem for financial firms. Standard models of value and interest rate risk (duration), based on the competitive market paradigm, are inappropriate in retail markets characterized by sluggish price and quantity behavior. Although the penetration of sophi...

Efforts to identify alternative sources of energy have focused on extracting natural gas from vast shale deposits. The Marcellus Shale, located in western New York, Pennsylvania, and Ohio, is estimated to contain enough natural gas to supply the United States for the next 45 years. New drilling technology-horizontal drilling and high-volume hydraulic fracturing of shale (fracking)-has made gas ...

BACKGROUND Direct, real-time visualization of the hard and soft tissues within the gingival sulcus may aid the clinician in diagnosis and therapy of periodontal disease. This report describes an endoscope specifically designed for this purpose and the interpretation of dental endoscopic images. METHODS Medical endoscope technology was modified for application in the dental environment. A fixe...

Cueva de los Aviones (southeast Spain) is a site of the Neandertal-associated Middle Paleolithic of Europe. It has yielded ochred and perforated marine shells, red and yellow colorants, and shell containers that feature residues of complex pigmentatious mixtures. Similar finds from the Middle Stone Age of South Africa have been widely accepted as archaeological proxies for symbolic behavior. U-...