Purpose: Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) is used in cancer imaging to probe tumor vascular properties. Compressed sensing (CS) theory makes it possible to recover MR images from randomly undersampled -space data using nonlinear recovery schemes. The purpose of this paper is to quantitatively evaluate common temporal sparsity-promoting regularizers for CS DCE-MRI of the breast.
Methods: We considered five ubiquitous temporal regularizers on 4.5x retrospectively undersampled Cartesian in vivo breast DCE-MRI data: Fourier transform (FT), Haar wavelet transform (WT), total variation (TV), second-order total generalized variation (TGV ), and nuclear norm (NN). We measured the signal-to-error ratio (SER) of the reconstructed images, the error in tumor mean, and concordance correlation coefficients (CCCs) of the derived pharmacokinetic parameters (volume transfer constant) and (extravascular-extracellular volume fraction) across a population of random sampling schemes.
Results: NN produced the lowest image error (SER: 29.1), while TV/TGV produced the most accurate (CCC: 0.974/0.974) and (CCC: 0.916/0.917). WT produced the highest image error (SER: 21.8), while FT produced the least accurate (CCC: 0.842) and (CCC: 0.799).
Conclusion: TV/TGV should be used as temporal constraints for CS DCE-MRI of the breast.
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http://dx.doi.org/10.1155/2017/7835749 | DOI Listing |
Ophthalmol Sci
November 2024
Casey Eye Institute, Oregon Health and Science University, Portland, Oregon.
Purpose: Retinopathy of prematurity (ROP) stage is defined by the visual appearance of the vascular-avascular border, which reflects a spectrum of pathologic neurovascular tissue (NVT). Previous work demonstrated that the thickness of the ridge lesion, measured using OCT, corresponds to higher clinical diagnosis of stage. This study evaluates whether the volume of anomalous NVT (ANVTV), defined as abnormal tissue protruding from the regular contour of the retina, can be measured automatically using deep learning to develop quantitative OCT-based biomarkers in ROP.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Optical Engineering, Utsunomiya University, 7-2-1 Yoto, Utsunomiya 321-8585, Japan.
We describe the various steps of a gas imaging algorithm developed for detecting, identifying, and quantifying gas leaks using data from a snapshot infrared spectral imager. The spectral video stream delivered by the hardware allows the system to combine spatial, spectral, and temporal correlations into the gas detection algorithm, which significantly improves its measurement sensitivity in comparison to non-spectral video, and also in comparison to scanning spectral imaging. After describing the special calibration needs of the hardware, we show how to regularize the gas detection/identification for optimal performance, provide example SNR spectral images, and discuss the effects of humidity and absorption nonlinearity on detection and quantification.
View Article and Find Full Text PDFAntibiotics (Basel)
January 2025
Department of Pharmacology and Toxicology, University of Veterinary Medicine, H-1078 Budapest, Hungary.
Background: Antimicrobial resistance is one of the greatest challenges of our time, urging researchers in both veterinary and public health to engage in collaborative efforts, thereby fostering the One Health approach. Infections caused by species can not only lead to significant diseases in poultry but also pose serious threats to human life, particularly in hospital (nosocomial) infections; therefore, it is crucial to identify their antimicrobial resistance.
Methods: Our objective was to assess the susceptibility profile of commensal strains ( = 227) found in commercial chicken flocks in Hungary through the determination of minimum inhibitory concentration (MIC) values.
Aust N Z J Public Health
January 2025
School of Population Health, Faculty of Medicine and Health, University of New South Wales, Kensington, NSW, Australia; College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia. Electronic address:
Objective: To quantify drowning rates and fatal to non-fatal drowning ratios on public holidays, school holidays, weekdays and long weekends in New South Wales from January 2010 to June 2022.
Methods: Using a linked administrative dataset comprising ambulance (paper-based and electronic records), emergency department presentations and death registry, rates of drowning and ratios of fatal to non-fatal drowning were calculated.
Results: Across 4,161 total drowning incidents, public holidays (14.
Neural Netw
January 2025
Hebei Key Laboratory of Marine Perception Network and Data Processing, Northeastern University (Qinhuangdao), Qinhuangdao 066004, China. Electronic address:
Entity alignment (EA) is a typical strategy for knowledge graph integration, aiming to identify and align different entity pairs representing the same real object from different knowledge graphs. Temporal Knowledge Graph (TKG) extends the static knowledge graph by introducing timestamps. However, since temporal knowledge graphs are constructed based on their own data sources, this usually leads to problems such as missing or redundant entity information in the temporal knowledge graph.
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