Positron Emission Mammography (PEM) is a planar imaging method that utilizes arrays of discrete detector elements for the detection of radiotracer-avid breast cancer. In this investigation we have systematically studied, through computer simulations, the effect of detector element size (width and length) on breast lesion detection and localization tasks. The contrast-to-noise ratios of the spheres simulating breast lesions were calculated as a function of detector element dimension to gauge detectability. System resolution (fwhm) across the field-of-view was used as the metric for the localization task. For both tasks, individual detector elements of lyso with cross sectional dimensions of 2x2 mm (96x72 element arrays, step 2.1mm) and 3x3mm (65x49 element arrays, step 3.1 mm), and lengths of 10,15 and 20 mm were simulated. The results revealed that narrower pixel dimensions reduced the partial volume effect, while the thicker pixels increased pixel sensitivity, thus reducing noise per pixel and increasing the contrast-to-noise ratio.
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http://dx.doi.org/10.1016/S1120-1797(06)80031-1 | DOI Listing |
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
December 2024
Department of Endocrinology, The Fourth Hospital of Changsha(Changsha Hospital of Hunan Normal University), Changsha 410000, China.
Objective To investigate the role and possible mechanism of glycogen synthase kinase-3 beta (GSK-3β)/cAMP response element binding protein (CREB) signaling pathway in regulating macrophage pyroptosis in the pathogenesis and development of diabetic foot ulcer (DFU). Methods Thirty rats were randomly divided into control group, DFU group and GSK-3β inhibited group, with 10 rats in each group. Fasting blood glucose (FBG) was detected by dynamic blood glucose detector.
View Article and Find Full Text PDFSci Rep
December 2024
School of Petroleum and Natural Gas Engineering, Southwest Petroleum University, Chengdu, 610500, China.
Accurately determining the initial acoustic field excitation load of a piezoelectric ultrasonic probe is essential for simulating electrical signals and calculating wall thickness during ultrasonic internal inspection of pipelines. A new method for determining the initial excitation load of the acoustic field is proposed, incorporating the focusing effect of the curved surface of pipelines on the ultrasonic signal from the piezoelectric ultrasonic probe. Finite element models were established for the new and old methods using COMSOL software, facilitating the analysis of the initial acoustic field distribution and associated electrical signal characteristics.
View Article and Find Full Text PDFEnviron Monit Assess
December 2024
School of Nuclear and Allied Sciences, University of Ghana, Atomic Campus, P.O. Box LG 80 Legon, Accra, Ghana.
Excavation of terrestrial surface of the Earth could enhance the chance of exposure to radon while gases in the underground get access to escape. This study was aimed to assess the level of radon concentration from soil samples of quarrying sites at Hakim Gara in Ethiopia using CR-39 detectors in sealed container technique. The results of the measured radon concentration level were ranging from 164.
View Article and Find Full Text PDFBiosensors (Basel)
December 2024
Escuela de Biotecnología, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Camino La Pirámide 5750, Huechuraba, Santiago 8580745, Chile.
The COVID-19 pandemic has prompted the need for the development of new biosensors for SARS-CoV-2 detection. Particularly, systems with qualities such as sensitivity, fast detection, appropriate to large-scale analysis, and applicable in situ, avoiding using specific materials or personnel to undergo the test, are highly desirable. In this regard, developing an electrochemical biosensor based on peptides derived from the angiotensin-converting enzyme receptor 2 (ACE2) is a possible answer.
View Article and Find Full Text PDFProbl Radiac Med Radiobiol
December 2024
State Institution «O.M. Marzіeiev Institute for Public Health of the National Academy of Medical Sciences of Ukraine», 50 Hetman Pavlo Polubotok Str., Kyiv, 02094, Ukraine.
Objective: assessment of probable exposure levels from radon and NORM in workplaces within the context of justi fying radiation protection plans in an existing exposure situation.
Materials And Methods: Materials regarding the assessment of naturally occurring radioactive material (NORM) con tent in tailing from mining and processing industries in Ukraine and assessments of contamination levels of industri al sites of oil and gas enterprises were used for estimating the probable range of effective doses (ED) of workers fromNORM at industrial enterprises. These materials were obtained as a result of research conducted by specialists from theRadiation Protection Laboratory of the State Institution «O.
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