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1.
Phys Rev Lett ; 106(8): 085003, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21405579

RESUMO

The first soft x-ray radiation flux measurements from hohlraums using both a 96 and a 192 beam configuration at the National Ignition Facility have shown high x-ray conversion efficiencies of ∼85%-90%. These experiments employed gold vacuum hohlraums, 6.4 mm long and 3.55 mm in diameter, heated with laser energies between 150-635 kJ. The hohlraums reached radiation temperatures of up to 340 eV. These hohlraums for the first time reached coronal plasma conditions sufficient for two-electron processes and coronal heat conduction to be important for determining the radiation drive.

2.
Phys Rev Lett ; 106(8): 085004, 2011 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-21405580

RESUMO

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 µm diameter hot core.

3.
Rev Sci Instrum ; 81(10): 10E321, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21034019

RESUMO

The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ∼20 times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ∼2×10(15) W/cm(2) for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×10(14) W/cm(2) over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums.

4.
Rev Sci Instrum ; 81(10): 10E538, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21034065

RESUMO

The static x-ray imager at the National Ignition Facility is a pinhole camera using a CCD detector to obtain images of Hohlraum wall x-ray drive illumination patterns seen through the laser entrance hole (LEH). Carefully chosen filters, combined with the CCD response, allow recording images in the x-ray range of 3-5 keV with 60 µm spatial resolution. The routines used to obtain the apparent size of the backlit LEH and the location and intensity of beam spots are discussed and compared to predictions. A new soft x-ray channel centered at 870 eV (near the x-ray peak of a 300 eV temperature ignition Hohlraum) is discussed.

5.
Arch Facial Plast Surg ; 3(4): 277-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11710866

RESUMO

Tumescent liposuction is a procedure with a good safety record. Local infection is rare but can result in devastating consequences. We report a rare case of group A streptococcal fasciitis complicating tumescent liposuction and highlight the importance of early diagnosis and treatment of this condition. A 62-year-old woman presented 8 days after submental liposuction and a platysmal plication procedure with signs and symptoms of cervical fasciitis. Microbiological analysis confirmed a group A streptococcal infection. By using early aggressive medical and surgical treatments, the disease was arrested before the onset of any necrotizing process. A high index of suspicion is required to make an early diagnosis of this potentially disfiguring and life-threatening infection.


Assuntos
Fasciite/etiologia , Lipectomia/efeitos adversos , Infecções Estreptocócicas/etiologia , Streptococcus pyogenes , Fasciite/diagnóstico , Fasciite/terapia , Feminino , Humanos , Pessoa de Meia-Idade , Pescoço , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/terapia
6.
Praxis (Bern 1994) ; 85(14): 454-8, 1996 Apr 02.
Artigo em Alemão | MEDLINE | ID: mdl-8657983

RESUMO

Departing from a report on today's understanding about nursing, the demanding duties nurses see themselves confronted with are featured in connection with the theme of this meeting. In a second part, difficulties in daily practise are treated. Furthermore, problematic aspects of collaboration within the nursing staff as well as between the disciplines burdening patients are covered. Possible improvements are proposed.


Assuntos
Relações Enfermeiro-Paciente , Defesa do Paciente , Atitude do Pessoal de Saúde , Atitude Frente a Morte , Comunicação , Humanos , Relações Interprofissionais , Masculino , Enfermeiras e Enfermeiros/psicologia , Prognóstico
8.
J Nucl Med Allied Sci ; 24(3-4): 221-2, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7252587
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