Dixmier traces and some applications to noncommutative geometry

This is a survey of some recent advances in the theory of singular traces in which the authors have played some part and which were inspired by questions raised by the book of Alain Connes (Noncommutative Geometry, Academic Press 1994). There are some original proofs and ideas but most of the results have appeared elsewhere. Detailed information on the contents is contained in the Introduction.Comment: To appear in Russian Mathematical Surveys (in Russian). New version corrects Latex problems, minor errors and reference

Credit risk rating at large U.S. banks

Large banks use internally developed credit rating systems to differentiate the riskiness of their commercial loans. Internal ratings are an essential ingredient of effective credit risk management for such banks, whose commercial borrowers may number in the tens of thousands. This article describes these rating systems, how their design varies across institutions, and how they are used in risk management. The article also outlines conceptual and practical difficulties currently faced by banks in achieving accurate and consistent ratings and describes ways in which some institutions have attempted to deal with these difficulties. This article is based on a detailed review of policy documents and internal management reports from the fifty largest U.S. bank holding companies and interviews by the authors at a selection of these institutions.Credit ratings ; Risk

Amino acids and amino sugars in calcified tissues of portunid crabs

Amino acid and amino sugar in calcified tissues of portunid crab

Spitzer's mid-infrared view on an outer Galaxy Infrared Dark Cloud candidate toward NGC 7538

Infrared Dark Clouds (IRDCs) represent the earliest observed stages of clustered star formation, characterized by large column densities of cold and dense molecular material observed in silhouette against a bright background of mid-IR emission. Up to now, IRDCs were predominantly known toward the inner Galaxy where background infrared emission levels are high. We present Spitzer observations with the Infrared Camera Array toward object G111.80+0.58 (G111) in the outer Galactic Plane, located at a distance of ~3 kpc from us and ~10 kpc from the Galactic center. Earlier results show that G111 is a massive, cold molecular clump very similar to IRDCs. The mid-IR Spitzer observations unambiguously detect object G111 in absorption. We have identified for the first time an IRDC in the outer Galaxy, which confirms the suggestion that cluster-forming clumps are present throughout the Galactic Plane. However, against a low mid-IR back ground such as the outer Galaxy it takes some effort to find them.Comment: Accepted for publication in ApJL -- 11 pages, 2 figures (1 colour

Cloze Encounters of a Different Kind

The cloze test usually consists of a graded reading passage from which words have been deleted according to some methodical strategy. such as every fifth word. every tenth word. every pronoun. etc. The deleted words are replaced with blanks of a uniform size. and the student is asked to fill in the blanks with the most appropriate word