2,381 research outputs found
Conformal defects in supergravity - backreacted Dirac delta sources
We construct numerically gravitational duals of theories deformed by
localized Dirac delta sources for scalar operators both at zero and at finite
temperature. We find that requiring that the backreacted geometry preserves the
original scale invariance of the source uniquely determines the potential for
the scalar field to be the one found in a certain Kaluza-Klein compactification
of supergravity. This result is obtained using an efficient perturbative
expansion of the backreacted background at zero temperature and is confirmed by
a direct numerical computation. Numerical solutions at finite temperatures are
obtained and a detailed discussion of the numerical approach to the treatment
of the Dirac delta sources is presented. The physics of defect configurations
is illustrated with a calculation of entanglement entropy.Comment: 23 pages, 12 figure
The most important medical source: Aunt Mabel knows best.
Not so long ago, one of us was consulted by a middle-aged woman with rosacea. For many years, she had had periodic flares of red papules and pustules on her nose and the adjoining areas. The confluent telangiectasia on her cheeks gave a permanent appearance of well-applied rouge. She had seen several dermatologists and had received a wide variety of medications, all of which seemed appropriate except to her as would be subsequently revealed. She wanted a new approach, but there were limitations placed upon her request: no pills or capsules; nothing odiferous; no agent that might bleach clothing; and nothing that would interfere with her night creams, eye restorer, or wrinkle control. All of these had been recommended by the cosmetic consultant – that is, the person behind the cosmetic counter who wears a white coat. [1] (Figure 1
Dermatology 75 years ago.
It seems that the practicing dermatologist in 2007 is being attacked on all fronts. The Food and Drug Administration has mandated a cumbersome program for monitoring isotrentinoin usage, its analogue barely comes under scrutiny. iPledge is just a plain nightmare. The acumen of the board certified dermatologist is being challenged by Maintenance of Certification proposals because other specialties are doing it; yet, the neighborhood pharmacist is unhampered in dispensing all sorts of advice about treatment. The insurance clerk thrives on denying medication, prescribed by the physician, using flawed reasoning or else suggesting that a ten days’ supply of medicine should be increased to 90 days in the name of economy, thus even further demeaning the sacrosanct prescription concept
Updating the dermatologic nomenclature: names that are good or bad.
Dermatology probably has the largest vocabulary of any of the medical specialties,1 a statement to which we can attest when we reviewed aspects of the Dermatology Lexicon project. Some terms are derived from the Latin or Greek and present spelling problems to all but a select few. Examples include acrokeratosis verruciformis and pterigium. Other diseases carry names that are such a mouthful that few can call them out without the interruption of breathing. These might include erosio interdigitalis blastomycetica and dermatitis exudative discoid and lichenoid of Sulzberger and Garbe. No wonder the former is now referred to simply as candidosis, or is it, candidiasis, and the latter as oid-oid disease or Sulzberger-Garbe disease
Barnacles, old age marks, or just plain seborrheic keratoses.
Growing older may mean more wrinkles and creaking joints, but why does it also entail an accumulation of barnacles. These brown, somewhat friable, often warty lesions are more common on senior citizens but are not necessarily limited to the chronologically challenged. Seborrheic keratoses (SKs) can be easily recognized (fig 1), but the itching and the occasional scratch-induced dermatitis make them more than a cosmetic nuisance. (fig 2)
SKs can go by a variety of names, ranging from basal cell papillomas, senile warts, and senile keratoses to seborrheic verrucae and verrucous senilis. The various terms provide no more information on their natural history or the etiology of these benign lesions, other than that age is somehow associated. (1
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