19 research outputs found
Acoustic phonon exchange, attractive interactions, and the Wentzel-Bardeen singularity in single-wall nanotubes
We derive the effective low-energy theory for interacting electrons in
metallic single-wall carbon nanotubes taking into account acoustic phonon
exchange within a continuum elastic description. In many cases, the nanotube
can be described as a standard Luttinger liquid with possibly attractive
interactions. We predict surprisingly strong attractive interactions for thin
nanotubes. Once the tube radius reaches a critical value \AA, the Wentzel-Bardeen singularity is approached, accompanied by strong
superconducting fluctuations. The surprisingly large indicates that this
singularity could be reached experimentally. We also discuss the conditions for
a Peierls transition due to acoustic phonons.Comment: 11 pages, 2 figures, final version to be published in Phys. Rev.
Influência da concentração de BAP e AG3 no desenvolvimento in vitro de mandioquinha-salsa
IgE allergy diagnostics and other relevant tests in allergy, a World Allergy Organization position paper
Currently, testing for immunoglobulin E (IgE) sensitization is the cornerstone of diagnostic evaluation in suspected allergic conditions. This review provides a thorough and updated critical appraisal of the most frequently used diagnostic tests, both in vivo and in vitro. It discusses skin tests, challenges, and serological and cellular in vitro tests, and provides an overview of indications, advantages and disadvantages of each in conditions such as respiratory, food, venom, drug, and occupational allergy. Skin prick testing remains the first line approach in most instances; the added value of serum specific IgE to whole allergen extracts or components, as well as the role of basophil activation tests, is evaluated. Unproven, non-validated, diagnostic tests are also discussed. Throughout the review, the reader must bear in mind the relevance of differentiating between sensitization and allergy; the latter entails not only allergic sensitization, but also clinically relevant symptoms triggered by the culprit allergen