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1.
Appl Opt ; 47(19): 3494-9, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18594596

RESUMO

A single beamline of the National Ignition Facility (NIF) has been operated at a wavelength of 526.5 nm (2 omega) by frequency converting the fundamental 1053 nm (1 omega) wavelength with an 18.2 mm thick type-I potassium dihydrogen phosphate (KDP) second-harmonic generator (SHG) crystal. Second-harmonic energies of up to 17.9 kJ were measured at the final optics focal plane with a conversion efficiency of 82%. For a similarly configured 192-beam NIF, this scales to a total 2 omega energy of 3.4 MJ full NIF equivalent (FNE).

2.
Appl Opt ; 46(16): 3276-303, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17514286

RESUMO

The National Ignition Facility (NIF) is the world's largest laser system. It contains a 192 beam neodymium glass laser that is designed to deliver 1.8 MJ at 500 TW at 351 nm in order to achieve energy gain (ignition) in a deuterium-tritium nuclear fusion target. To meet this goal, laser design criteria include the ability to generate pulses of up to 1.8 MJ total energy, with peak power of 500 TW and temporal pulse shapes spanning 2 orders of magnitude at the third harmonic (351 nm or 3omega) of the laser wavelength. The focal-spot fluence distribution of these pulses is carefully controlled, through a combination of special optics in the 1omega (1053 nm) portion of the laser (continuous phase plates), smoothing by spectral dispersion, and the overlapping of multiple beams with orthogonal polarization (polarization smoothing). We report performance qualification tests of the first eight beams of the NIF laser. Measurements are reported at both 1omega and 3omega, both with and without focal-spot conditioning. When scaled to full 192 beam operation, these results demonstrate, to the best of our knowledge for the first time, that the NIF will meet its laser performance design criteria, and that the NIF can simultaneously meet the temporal pulse shaping, focal-spot conditioning, and peak power requirements for two candidate indirect drive ignition designs.

3.
Appl Opt ; 32(15): 2664-73, 1993 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-20820428

RESUMO

The remote alignment of segmented mirror active optics with far-field optimization is reported. Farfield optimization eliminates the need for a wave-front sensor or gap sensors since it does not require any near-field measurements, but uses simple measures of the point-spread function as figures of merit. The simplex function minimization algorithm is used to configure iteratively the segmented mirror toalignment. We present results of computer simulations to demonstrate the application of far-field optimization to the segmented mirror alignment in the presence of atmospheric turbulence. The effects of static as well as dynamic Kolmogorov turbulence (turbulence phase screen drifting across the telescope aperture) are studied. We find that the segmented mirror alignment is fairly insensitive to the speed of drifting turbulence and aligns a segmented mirror active optical system with adequate correction bandwidth in a few seconds.

4.
Br J Nutr ; 68(2): 445-50, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1445824

RESUMO

The glycaemic index (GI) and the triacylglycerol response were measured in thirty non-insulin-dependent diabetes mellitus patients given 50 g portions of five different conventional Indian meals containing semolina (Triticum aestivum) cooked by two different methods, or combinations of semolina and pulse (black gram dhal (Phaseolus mungo), green gram dhal (Phaseolus aureus) or Bengal gram dhal (Cicer arietum)). There were no significant differences among meals in mean GI except for meals based on roasted semolina or semolina-black gram dhal. Compared with the blood glucose response for a 50 g glucose load, only meals based on steam-cooked semolina and semolina-Bengal gram dhal elicited a significantly lower response at 1 h postprandially, and only meals based on semolina-black gram dhal at 2 h postprandially. No significant differences were found among the meals in the triacylglycerol-response.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Carboidratos da Dieta/metabolismo , Fabaceae , Feminino , Teste de Tolerância a Glucose , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Oryza , Plantas Medicinais , Triglicerídeos/metabolismo
5.
Plant Foods Hum Nutr ; 42(2): 175-82, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1315434

RESUMO

The effect of dry Sundakai powder supplementation (7 g providing 1.23 g of crude fibre) on glycemic control, lipidemic control, total amino acids and uronic acid was studied on 30 non-insulin dependent diabetes mellitus patients. All the patients were on hypoglycemic drugs. The above parameters were monitored at day 1, 15 and 30 days. After one month of fibre supplementation, no significant changes were observed with respect to glucose, lipid profile, glycated proteins, total amino acids and uronic acid levels in these subjects.


Assuntos
Aminoácidos/sangue , Proteínas Sanguíneas/análise , Diabetes Mellitus Tipo 2/dietoterapia , Fibras na Dieta/administração & dosagem , Lipídeos/sangue , Glicemia/análise , Colesterol/sangue , Feminino , Glicoproteínas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Urônicos/sangue , Verduras
6.
Appl Opt ; 31(30): 6510-8, 1992 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-20733869

RESUMO

A novel approach for the remote alignment of segmented mirrors is presented. In comparison with conventional methods in which near-field measurements (in the form of displacements between neighboring segments or phase across the mirror) are used in a feedback control system, the far-field optimization method utilizes only attributes of the point-spread function. A figure of merit based on the far-field intensity is used to configure iteratively the segmented mirror to alignment. Following computer simulations, we conduct successful laboratory experiments to validate the far-field optimization concept. The potential utility of far-field optimization to the alignment of other adaptive optical systems and to dynamic wave-front control is briefly discussed.

7.
J Am Coll Nutr ; 9(6): 573-7, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2273190

RESUMO

The glycemic index (GI) was determined in 36 non-insulin-dependent diabetes mellitus patients who were fed 50 g carbohydrate portions of six Indian conventional foods, including rice, a combination of rice-legume (Bengalgram, peas, and greengram), and a combination of rice-dal (greengram dal and redgram dal -- dal is dehusked and split legume). In addition to the GI, triglyceride (TG) responses of these foods were also determined. A higher GI was obtained for rice and for rice with peas; all other combinations yielded lower glycemic indices. However, all the foods produced significantly lower blood glucose response 2 hours postprandially as compared with blood glucose responses to a 50 g glucose load for the same group. No significant difference was observed for TG responses to the different foods.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/metabolismo , Carboidratos da Dieta/metabolismo , Diabetes Mellitus Tipo 2/sangue , Fabaceae , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Oryza , Plantas Medicinais , Triglicerídeos/sangue
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