Objective: This work describes a phantom containing regions of controlled R2* (1/T2*) values to provide a stable reference object for testing implementations of R2* relaxometry commonly used for liver and heart iron assessments.
Materials And Methods: A carrageenan-strengthened gadolinium DTPA doped agarose gel was used to enclose nine gels additionally doped with ultra-small superparamagnetic iron oxide. R2* values were determined at 1.5 T using multi-echo GRE sequences and exponential regression of pixel values from a region of interest against echo time using non-linear regression algorithms. We measured R2*, R2 and R1 values and the inter-scan and inter-operator reproducibility.
Results: The phantom reliably demonstrated R2* values in seven steps between 22.4 s (SE 1.98) and 441.9 s (SE 6.76), with an R2* relaxivity (r2*) of 792 (SE 5.6) mM s. The doped gels displayed a concentration-dependent R2' component of R2* phantom, indicating superparamagnetic enhancement effects. We observed no significant change in relaxivity (r2*) over 12 months, and estimate a useful life of 3 years. Detailed descriptions of the production process and calculators are been provided as Online Resources.
Conclusion: The phantom provides a durable test object with controlled R2* relaxation behaviour, useful for a range of R2* relaxometry reference work.
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http://dx.doi.org/10.1007/s10334-016-0576-x | DOI Listing |
Integr Environ Assess Manag
January 2025
División de Estudios de Posgrado e Investigación, Tecnológico Nacional de México/IT de Culiacán, Culiacán, Sinaloa, México.
Eutrophication is one of the most relevant concerns due to the risk to water supply and food security. Nitrogen and phosphorus chemical species concentrations determined the risk and magnitude of eutrophication. These analyses are even more relevant in basins with intensive agriculture due to agrochemical discharges.
View Article and Find Full Text PDFPLoS One
January 2025
Division of General Internal Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
Objective: Identify the most important sociodemographic and behavioral factors related to the diet of low-income adults with hypertension in order to guide the development of a community health worker (CHW) healthy eating intervention for low-income populations with hypertension.
Design: In this cross-sectional analysis, dietary recalls were used to assess Healthy Eating Index-2020 (HEI-2020) total (range: 0 to 100 [best diet quality]) and component scores and sodium intake. Self-reported sociodemographic and behavioral data were entered into a Least Absolute Shrinkage and Selection Operator (LASSO) regression model to determine the relative importance of factors related to diet quality.
PLoS One
January 2025
Faculty of Philosophy, Department of Psychology, University of Novi Sad, Novi Sad, Serbia.
Virtual reality (VR) provides a unique opportunity to simulate various environments, enabling the observation of human behavior in a manner that closely resembles real-world scenarios. This study aimed to explore the effects of anticipating reward or punishment, personality traits, and physiological arousal on risky decision-making within a VR context. A custom VR game was developed to simulate real-life experiences.
View Article and Find Full Text PDFPLoS One
January 2025
Vista Aria Rena Gene Inc., Gorgan, Golestan, Iran.
Due to its global burden, Targeting Hepatitis B virus (HBV) infection in humans is crucial. Herbal medicine has long been significant, with flavonoids demonstrating promising results. Hence, the present study aimed to establish a way of identifying flavonoids with anti-HBV activities.
View Article and Find Full Text PDFInvest Radiol
January 2025
From the Department of Radiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany (D.B.M., J.O.K., J.B., A.K., J.M., J.L.H., C.R., M.T., B.H., M.R.M.); Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany (D.B.M., J.O.K., J.B., A.K., L.C.A., M.R.M.); Department of Chemistry, Humboldt-Universität zu Berlin, Berlin, Germany (J.O.K.); Division 1.5 Protein Analysis, Federal Institute for Materials Research and Testing, Berlin, Germany (J.O.K., M.G.W.); Department of Biology, Chemistry, and Pharmacy, Institute of Biology, Freie Universität Berlin, Berlin, Germany (A.K.); Department of Veterinary Medicine, Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Freie Universität Berlin, Berlin, Germany (J.L.H.); Institute of Inorganic and Analytical Chemistry, University of Münster, Münster, Germany (C.V., P.N., U.K.); Department of Cardiology, Angiology and Intensive Care Medicine, Deutsches Herzzentrum der Charité, Berlin, Germany (A.L.); DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, Berlin, Germany (A.L.); and Division of Cardiology, Massachusetts General Hospital, Harvard University, Boston, MA (W.C.P.).
Introduction: Atherosclerosis is the underlying cause of multiple cardiovascular pathologies. The present-day clinical imaging modalities do not offer sufficient information on plaque composition or rupture risk. A disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4) is a strongly upregulated proteoglycan-cleaving enzyme that is specific to cardiovascular diseases, inter alia, atherosclerosis.
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