Richard A. Schwartz

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A patient who had linear scleroderma associated with ipsilateral hemiatrophy of the tongue and subsequent facial hemiatrophy was studied. Biopsy specimens of the plaque of scleroderma showed the skin changes of scleroderma as well as fascial and muscle changes. The fascia had an impressive plasma cell fasciitis with numerous plasma cells and scattered(More)
A 62-year-old woman who had a history of asthma and allergic rhinitis developed bilateral pulmonary infiltrates and marked eosinophilia. A transbronchial biopsy specimen did not help clarify the diagnosis. She later developed erythematous nodules on her feet; results of a biopsy specimen revealed necrotizing extravascular granulomas and marked infiltration(More)
Metastatic lesions of the CNS developed in two male patients with disseminated Kaposi's sarcoma. One patient was a homosexual, but the second patient had no apparent risk factors for disseminated Kaposi's sarcoma. These cases indicate that CNS involvement by tumor should be suspected in patients with Kaposi's sarcoma who exhibit abnormal neurologic signs or(More)
We investigate the conversion of the 0.5–4 and 1–8 ˚ A soft X–ray flux measurements made by detectors on the Geostationary Operational Environmental Satellites (GOES) into temperature and emission measures of coronal plasma using modern spectral models and modern understanding of coronal abundances. In particular, the original analysis by Thomas, Starr &(More)
The observed hard X-ray (HXR) flux spectrum I(ǫ) from solar flares is a combination of primary bremsstrahlung photons IP (ǫ) with a spectrally modified component from photospheric Compton backscatter of downward primary emission. The latter can be significant, distorting or hiding the true features of the primary spectrum which are key diagnostics for(More)
The Reuven Ramaty High Energy Solar Spectroscopy Imager (RHESSI) has obtained the first high-resolution measurements of nuclear de-excitation lines produced by energetic ions accelerated in a solar flare, a GOES X4.8 event occurring on 23 July, 2002 at a heliocentric angle of ∼ 73 o. Lines of neon, magnesium, silicon, iron, carbon, and oxygen were resolved(More)
Saturation affects a significant rate of images recorded by the Atmospheric Imaging Assembly on the Solar Dynamics Observatory. This paper describes a computational method and a technological pipeline for the de-saturation of such images, based on several mathematical ingredients like Expectation Maximization, image correlation and interpolation. An(More)
A multi-wavelength spatial and temporal analysis of solar high energy electrons is conducted using the August 20, 2002 flare of an unusually flat (γ1 = 1.8) hard X-ray spectrum. The flare is studied using RHESSI, Hα, radio, TRACE, and MDI observations with advanced methods and techniques never previously applied in the solar flare context. A new method to(More)
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