1000 resultados para Cone, Spencer Houghton, 1785-1855.


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The article retraces the career of the famous hypnotist Onofroff and particularly his visit to Buenos Aires, where his activity, in 1895, provoked many discussions and some public embarrassment. In this context Darío, using a pseudonym, published his crónica “La esfinge”. We reproduce “La esfinge”, transcribing the original text of La Nación, with annotations identifying the literary and theosophical sources Darío used when he wrote it.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We have developed a PW (0.5 ps/500J) laser system to demonstrate fast heating of imploded core plasmas using a hollow cone shell target. Significant enhancement of thermal neutron yield has been realized with PW-laser heating, confirming that the high heating efficiency is maintained as the short-pulse laser power is substantially increased to a value nearly equivalent to the ignition condition. It appears that the efficient heating is realized by the guiding of the PW laser pulse energy within the hollow cone and by self-organized relativistic electron transport. Based on the experimental results, we are developing a 10kJ-PW laser system to study the fast heating physics of high-density plasmas at an ignition-equivalent temperature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We studied an eye from a 73-year-old man with a sporadic type of retinal cone degeneration and choroidal melanoma. Histologic and ultrastructural studies of the nasal retina unaffected by the choroidal melanoma showed alterations at the outer retina predominantly involving the photoreceptors and retinal pigment epithelium. A wide spectrum of pathologic changes were observed, ranging from near normal retina showing only photoreceptor outer segment disease (distortion and kinking) to grossly pathologic regions where photoreceptor cell bodies were sparse and their outer segments absent. The retinal pigment epithelium in minimally affected regions of the retina showed an increased proportion of the melanin complement of the cell within complex granules. In severe disease, many cells showed only giant complex granules with no free melanin. Retinal pigment epithelial cell migration and relocation around blood vessels was also noted in severe disease.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A scheme in which carbon ion bunches are accelerated to a high energy and density by a laser pulse (∼10 W/cm) irradiating cone targets is proposed and investigated using particle-in-cell simulations. The laser pulse is focused by the cone and drives forward an ultrathin foil located at the cone's tip. In the course of the work, best results were obtained employing target configurations combining a low-Z cone with a multispecies foil transversely shaped to match the laser intensity profile. © 2014 AIP Publishing LLC.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background and purpose: We are developing a technique for highly focused vocal cord irradiation in early glottic carcinoma to optimally treat a target volume confined to a single cord. This technique, in contrast with the conventional methods, aims at sparing the healthy vocal cord. As such a technique requires sub-mm daily targeting accuracy to be effective, we investigate the accuracy achievable with on-line kV-cone beam CT (CBCT) corrections. Materials and methods: CBCT scans were obtained in 10 early glottic cancer patients in each treatment fraction. The grey value registration available in X-ray volume imaging (XVI) software (Elekta, Synergy) was applied to a volume of interest encompassing the thyroid cartilage. After application of the thus derived corrections, residue displacements with respect to the planning CT scan were measured at clearly identifiable relevant landmarks. The intra- and inter-observer variations were also measured. Results: While before correction the systematic displacements of the vocal cords were as large as 2.4 ± 3.3 mm (cranial-caudal population mean ± SD Σ), daily CBCT registration and correction reduced these values to less than 0.2 ± 0.5 mm in all directions. Random positioning errors (SD σ) were reduced to less than 1 mm. Correcting only for translations and not for rotations did not appreciably affect this accuracy. The residue random displacements partly stem from intra-observer variations (SD = 0.2-0.6 mm). Conclusion: The use of CBCT for daily image guidance in combination with standard mask fixation reduced systematic and random set-up errors of the vocal cords to <1 mm prior to the delivery of each fraction dose. Thus, this facilitates the high targeting precision required for a single vocal cord irradiation. © 2009 Elsevier Ireland Ltd. All rights reserved.