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1.
Space Sci Rev ; 220(1): 1, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38130909

RESUMO

The Lucy Thermal Emission Spectrometer (L'TES) will provide remote measurements of the thermophysical properties of the Trojan asteroids studied by the Lucy mission. L'TES is build-to-print hardware copy of the OTES instrument flown on OSIRIS-REx. It is a Fourier Transform spectrometer covering the spectral range 5.71-100 µm (1750-100 cm-1) with spectral sampling intervals of 8.64, 17.3, and 34.6 cm-1 and a 7.3-mrad field of view. The L'TES telescope is a 15.2-cm diameter Cassegrain telescope that feeds a flat-plate Michelson moving mirror mounted on a linear voice-coil motor assembly to a single uncooled deuterated l-alanine doped triglycine sulfate (DLATGS) pyroelectric detector. A significant firmware change from OTES is the ability to acquire interferograms of different length and spectral resolution with acquisition times of 0.5, 1, and 2 seconds. A single ∼0.851 µm laser diode is used in a metrology interferometer to provide precise moving mirror control and IR sampling at 772 Hz. The beamsplitter is a 38-mm diameter, 1-mm thick chemical vapor deposited diamond with an antireflection microstructure to minimize surface reflection. An internal calibration cone blackbody target, together with observations of space, provides radiometric calibration. The radiometric precision in a single spectrum is ≤2.2 × 10-8 W cm-2 sr-1 /cm-1 between 300 and 1350 cm-1. The absolute temperature error is <2 K for scene temperatures >75 K. The overall L'TES envelope size is 37.6 × 29.0 × 30.4 cm, and the mass is 6.47 kg. The power consumption is 12.6 W average. L'TES was developed by Arizona State University with AZ Space Technologies developing the electronics. L'TES was integrated, tested, and radiometrically calibrated on the Arizona State University campus in Tempe, AZ. Initial data from space have verified the instrument's radiometric and spatial performance.

2.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28566259

RESUMO

The case involves a 34-year-old woman who underwent surgical removal of a retroperitoneal paraganglioma adjacent to the left kidney's lower pole, previously visualized by CT and MRI. The 123I-MIBG scan was positive for this lesion and, in addition, another uptake was observed located caudally at the level of L5 and of smaller size and less intensity. The second lesion was not considered for surgical removal, due to its lack of morphological definition. One week after surgical intervention, the patient presented difficult-to-control high blood pressure. A second 123I-MIBG scan was performed. The previously described second image was more intense in this study, and surgery was planned to remove it. A combination of techniques including freehand-SPECT and a portable hybrid gamma camera (with optical camera) were used pre-operatively to identify the location of the lesion. The combination of intra-operative laparoscopic gamma probe and portable hybrid gamma camera enabled the tumor to be located, excised, and its complete removal to be monitored. The histopathology analysis confirmed a second paraganglioma.


Assuntos
Imagem Multimodal , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Paraganglioma/diagnóstico por imagem , Radiografia Intervencionista/métodos , Neoplasias Retroperitoneais/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , 3-Iodobenzilguanidina , Adulto , Desenho de Equipamento , Feminino , Câmaras gama , Humanos , Radioisótopos do Iodo , Imageamento por Ressonância Magnética , Neoplasias Primárias Múltiplas/cirurgia , Paraganglioma/cirurgia , Cintilografia , Neoplasias Retroperitoneais/cirurgia , Tomografia Computadorizada por Raios X
3.
Rev Esp Med Nucl Imagen Mol ; 36(3): 175-184, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27793632

RESUMO

Radio-guided surgery has been developed for application in those disease scheduled for surgical management, particularly in areas of complex anatomy. This is based on the use of pre-operative scintigraphic planar, tomographic and fused SPECT/CT images, and the possibility of 3D reconstruction for the subsequent intraoperative locating of active lesions using handheld devices (detection probes, gamma cameras, etc.). New tracers and technologies have also been incorporated into these surgical procedures. The combination of visual and acoustic signals during the intraoperative procedure has become possible with new portable imaging modalities. In daily practice, the images offered by these techniques and devices combine perioperative nuclear medicine imaging with the superior resolution of additional optical guidance in the operating room. In many ways they provide real-time images, allowing accurate guidance during surgery, a reduction in the time required for tissue location and an anatomical environment for surgical recognition. All these approaches have been included in the concept known as (radio) Guided intraOperative Scintigraphic Tumour Targeting (GOSTT). This article offers a general view of different nuclear medicine and allied technologies used for several GOSTT procedures, and illustrates the crossing of technological frontiers in radio-guided surgery.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Cintilografia , Cirurgia Assistida por Computador , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Adulto Jovem
4.
Rev Esp Med Nucl Imagen Mol ; 35(6): 385-390, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27554661

RESUMO

Nuclear medicine traditionally employs planar and single photon emission computed tomography (SPECT) imaging techniques to depict the biodistribution of radiotracers for the diagnostic investigation of a range of disorders of endocrine gland function. The usefulness of combining functional information with anatomy derived from computed tomography (CT), magnetic resonance imaging (MRI), and high resolution ultrasound (US), has long been appreciated, either using visual side-by-side correlation, or software-based co-registration. The emergence of hybrid SPECT/CT camera technology now allows the simultaneous acquisition of combined multi-modality imaging, with seamless fusion of 3D volume datasets. Thus, it is not surprising that there is growing literature describing the many advantages that contemporary SPECT/CT technology brings to radionuclide investigation of endocrine disorders, showing potential advantages for the pre-operative locating of the parathyroid adenoma using a minimally invasive surgical approach, especially in the presence of ectopic glands and in multiglandular disease. In conclusion, hybrid SPECT/CT imaging has become an essential tool to ensure the most accurate diagnostic in the management of patients with hyperparathyroidism.


Assuntos
Adenoma/diagnóstico por imagem , Neoplasias das Paratireoides/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Imagem Multimodal
6.
Ann Biomed Eng ; 37(11): 2266-87, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19657741

RESUMO

The mechanics of arteries result from the properties of the soft tissue constituents and the interaction of the wall layers, predominantly media and adventitia. This concept was adopted in this study for the design of a tissue regenerative vascular graft. To achieve the desired structural properties of the graft, most importantly a diametric compliance of 6%/100 mmHg, finite element methods and genetic algorithms were used in an integrated approach to identify the mechanical properties of an adventitial fabric layer that were required to optimally complement an intimal/medial polyurethane layer with interconnected porosity of three different size classes. The models predicted a compliance of 16.0, 19.2, and 31.5%/100 mmHg for the non-reinforced grafts and 5.3, 5.5, and 6.0%/100 mmHg for the fabric-reinforced grafts. The latter, featuring fabrics manufactured according to the required non-linear mechanical characteristics numerically predicted, exhibited an in vitro compliance of 2.1 +/- 0.8, 3.0 +/- 2.4, and 4.0 +/- 0.7% /100 mmHg. The combination of finite element methods and genetic algorithms was shown to be able to successfully optimize the mechanical design of the composite graft. The method offers potential for the application to alternative concepts of modular vascular grafts and the incorporation of tissue ingrowth and biodegradation.


Assuntos
Artérias/fisiologia , Artérias/transplante , Bioprótese , Prótese Vascular , Modelos Cardiovasculares , Têxteis , Transplantes , Algoritmos , Simulação por Computador , Desenho Assistido por Computador , Análise de Elementos Finitos , Modelos Genéticos , Desenho de Prótese/métodos
7.
Int J Obes (Lond) ; 31(2): 321-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16703001

RESUMO

OBJECTIVE: To examine the association between health-related quality of life (HRQOL) and physical activity (PA). METHODS: Cross-sectional data were obtained via a national telephone survey from 9173 respondents (30.9% response rate; 51.4% cooperation rate). Four indicators of HRQOL were measured: self-rated health, physically unhealthy days, mentally unhealthy days and activity limitation days. Prevalence estimates were calculated by body mass index (BMI) category and PA level. Logistic regression evaluated BMI as an effect modifier of the relationship between HRQOL and PA. RESULTS: Inactive adults reported more fair to poor HRQOL than active adults, regardless of BMI category (P<0.001). BMI did not modify the association between PA and any of the four HRQOL indicators. CONCLUSION: Prevalence of low HRQOL is inversely related to PA participation, and the relationship is not altered by BMI status. Regardless of their weight status, adults should be encouraged to engage in PA.


Assuntos
Índice de Massa Corporal , Atividade Motora , Qualidade de Vida , Adolescente , Adulto , Distribuição por Idade , Idoso , Escolaridade , Métodos Epidemiológicos , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Redução de Peso
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