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1.
Rev Sci Instrum ; 93(8): 083516, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050109

RESUMO

The hardened single line of sight camera has been recently characterized in preparation for its deployment on the National Ignition Facility. The latest creation based on the pulse-dilation technology leads to many new features and improvements over the previous-generation cameras to provide better quality measurements of inertial confinement fusion experiments, including during high neutron yield implosions. Here, we present the characterization data that illustrate the main performance features of this instrument, such as extended dynamic range and adjustable internal magnification, leading to improved spatial resolution.

2.
Rev Sci Instrum ; 89(10): 10G123, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399697

RESUMO

A new generation of fast-gated x-ray framing cameras have been developed that are capable of capturing multiple frames along a single line-of-sight with 30 ps temporal resolution. The instruments are constructed by integrating pulse-dilation electron imaging with burst mode hybrid-complimentary metal-oxide-semiconductor sensors. Two such instruments have been developed, characterized, and fielded at the National Ignition Facility and the OMEGA laser. These instruments are particularly suited for advanced x-ray imaging applications in Inertial Confinement Fusion and High energy density experiments. Here, we discuss the system architecture and the techniques required for tuning the instruments to achieve optimal performance. Characterization results are also presented along with planned future improvements to the design.

3.
Rev Sci Instrum ; 89(10): 10G117, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399700

RESUMO

The single-line-of-sight, time-resolved x-ray imager (SLOS-TRXI) on OMEGA is one of a new generation of fast-gated x-ray cameras comprising an electron pulse-dilation imager and a nanosecond-gated, burst-mode, hybrid complementary metal-oxide semiconductor sensor. SLOS-TRXI images the core of imploded cryogenic deuterium-tritium shells in inertial confinement fusion experiments in the ∼4- to 9-keV photon energy range with a pinhole imager onto a photocathode. The diagnostic is mounted on a fixed port almost perpendicular to a 16-channel, framing-camera-based, time-resolved Kirkpatrick-Baez microscope, providing a second time-gated line of sight for hot-spot imaging on OMEGA. SLOS-TRXI achieves ∼40-ps temporal resolution and better than 10-µm spatial resolution. Shots with neutron yields of up to 1 × 1014 were taken without observed neutron-induced background signal. The implosion images from SLOS-TRXI show the evolution of the stagnating core.

4.
Rev Sci Instrum ; 89(10): 10G125, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399712

RESUMO

Crystal x-ray imaging is frequently used in inertial confinement fusion and laser-plasma interaction applications as it has advantages compared to pinhole imaging, such as higher signal throughput, better achievable spatial resolution, and chromatic selection. However, currently used x-ray detectors are only able to obtain a single time resolved image per crystal. The dilation aided single-line-of-sight x-ray camera described here was designed for the National Ignition Facility (NIF) and combines two recent diagnostic developments, the pulse dilation principle used in the dilation x-ray imager and a ns-scale multi-frame camera that uses a hold and readout circuit for each pixel. This enables multiple images to be taken from a single-line-of-sight with high spatial and temporal resolution. At the moment, the instrument can record two single-line-of-sight images with spatial and temporal resolution of 35 µm and down to 35 ps, respectively, with a planned upgrade doubling the number of images to four. Here we present the dilation aided single-line-of-sight camera for the NIF, including the x-ray characterization measurements obtained at the COMET laser, as well as the results from the initial timing shot on the NIF.

7.
Acta Otolaryngol ; 129(7): 779-85, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18767001

RESUMO

CONCLUSION: High convergent and discriminant validity between subscales was achieved after the translation of EORTC QLQ-H&N35 into Cantonese. Most subscales were assessing distinct components of quality of life (QoL). OBJECTIVES: The study aimed to translate the EORTC QLQ-H&N35 cancer module into Cantonese and to confirm validity and reliability for use in a Hong Kong head and neck (H&N) cancer population. SUBJECTS AND METHODS: An ethnocentric forward-backward translation of EORTC QLQ-H&N35 was conducted by bilingual head and neck health professionals. Discrepancies were identified and problematic wording and concepts revised. Further review preceded pilot testing in 119 postoperative H&N cancer patients. Internal consistency within each subscale, convergent and discriminant validity to check the item relevance and item representativeness within and between subscales were examined. Mean and standard deviations of each subscale and single item and Cronbach's alpha coefficients for subscales were calculated. RESULTS: Six of seven subscales achieved standard reliability (Cronbach's alpha coefficient >0.7). Correlation coefficients between an item and its own subscale were significantly higher than the coefficients with other subscales. Scaling success was found in all subscales. Pearson's correlation coefficient between subscales was <0.70, except between the subscales swallowing and trouble with social eating (r = 0.795), and speech problems and social contact (r = 0.754).


Assuntos
Comparação Transcultural , Neoplasias Otorrinolaringológicas/psicologia , Neoplasias Otorrinolaringológicas/cirurgia , Complicações Pós-Operatórias/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários , Tradução , Idoso , Transtornos de Deglutição/psicologia , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Otorrinolaringológicas/patologia , Projetos Piloto , Psicometria/estatística & dados numéricos , Reprodutibilidade dos Testes
8.
Acta fisiátrica ; 2(1): 19-22, dez. 1995. tab
Artigo em Português | LILACS | ID: lil-310061

RESUMO

A etiologia da distrofia simpático reflexa (DSR) é desconhecida, porém a teoria mais aceita é a de uma disfunçäo do Sistema Nervoso Simpático. Os achados clínicos caracterizam-se por neuropática, distúrbios nasomotores e sudomotores e alteraçöes tróficas da pele fque aumentam em estágios mais avançados. O diagnóstico é feito através da história clínica, exame físico, radiografias, cintilografia óssea e termografia. O tratamento baseia-se em meios físicos, como hidroterapia e exercícios terapêuticos. Quando há necessidade säo utilizados medicamentos que interferem no sistema modulador da dor como os antidepressivos tricíclicos e os neurolépticos. O objetivo deste estudo é o de apresentar os resultados do tratamento de 13 pacientes com DSR que foram submetidos a meios físicos e terapia medicamentosa quando necessário.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Tornozelo , Distrofia Simpática Reflexa/diagnóstico , , Medicina Física e Reabilitação
9.
J Formos Med Assoc ; 91(9): 849-58, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1363383

RESUMO

Dog pancreatic islets isolated by an enzymatic digestion method were encapsulated in an alginate-poly L-lysine-alginate membrane. These microencapsulated pancreatic islets were cultured in vitro to study their ability of insulin secretion. Portions of these in vitro-cultured microencapsulated pancreatic islets were taken out for a viability dye exclusion study as well as for pathologic studies to correlate them with insulin secretion ability. We found that there was a strong correlation between them. Good insulin-secreting microcapsules showed well-preserved cell membranes and beta-cell granules. An in vitro culture for one to two days in RPMI-1640 made the islets more stable, the cellular surface became smoother and the beta-granules were in better shape. The microencapsulated pancreatic islets were also injected into the peritoneum of streptozotocin-induced diabetic CDF1 mice. Blood glucose levels dropped and stayed low for up to 60 days. But, when non-encapsulated dog pancreatic islets were used, the blood glucose levels remained low for only about 14 days. A small portion of the injected microcapsules were washed out at specific times for pathologic study. Up to 28 days after injection, only a few of the injected microcapsules showed pericapsular cellular infiltrate. However, after 56 days, most of the microcapsules showed dense pericapsular cellular infiltrate. Immunohistochemical analysis of these infiltrates showed that the majority of cells were fibroblasts and macrophages. Most of the cells located in the inner portion of the infiltrate were fibroblasts, while the macrophages were located mainly on the outer portion. Both scanning and transmission electron microscopy showed that the surface of the microcapsule outer wall was much smoother than the inner wall. The size of the microcapsules was approximately 0.6-0.8 mm and the thickness of the wall measured around 10 nm. The smaller the microcapsule is, the less chance there is of rupture with release of the xenographic islets. Once the wall of the transplanted microcapsules was ruptured, the inner surface showed more increased inflammatory cell and fibroblast infiltration than the outer surface.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/patologia , Animais , Cães , Composição de Medicamentos , Feminino , Sobrevivência de Enxerto , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/fisiologia , Ilhotas Pancreáticas/ultraestrutura , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Transplante Heterólogo
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