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摘要： Background: A novel super-resolution deep learning reconstruction (SR-DLR) algorithm, trained using data acquired with ultra-high-resolution CT, can potentially enhance spatial resolution in coronary CT angiography (CCTA), improving stenosis assessment;however, evidence is limited. Purpose: To compare the performance of SR-DLR versus hybrid iterative reconstruction (HIR) in assessing coronary stenosis, using invasive coronary angiography (ICA) as the reference standard, and to explore the potential impact on patient-level Coronary Artery Disease Reporting and Data System (CAD-RADS) classification. Materials and Methods: From September 2023 to November 2024, patients who underwent clinically indicated CCTA and ICA within a 2-month interval were prospectively enrolled at 10 hospitals across China. CCTA images were reconstructed with both HIR and SR-DLR, and percentage diameter stenosis (PDS) of calcified, noncalcified, and mixed plaques was quantified. Participant-level CAD-RADS category was determined based on the highest-grade stenosis. Using ICA as the reference standard, diagnostic performance of HIR and SR-DLR in detecting significant stenosis (50% or greater stenosis) was compared using the area under the receiver operating characteristic curve (AUC). Results: The study included 204 individuals (mean age, 64.3 years +/- 9.1 [SD];137 male participants) with 605 plaques (175 calcified, 140 noncalcified, 290 mixed). Median PDS for calcified plaques was lower with SR-DLR than with HIR (58% [IQR, 44%-71%] vs 63% [IQR, 53%-85%];P < .001), with no evidence of a difference in median PDS for noncalcified (P = .09) or mixed (P = .40) plaques. Forty-one individuals were assigned a different CAD-RADS category with SL-DLR relative to HIR: 25 downgraded and 16 upgraded. SR-DLR outperformed HIR in detecting significant stenosis at the lesion level (AUC, 0.97 [95% CI: 0.96, 0.98] vs 0.90 [95% CI: 0.87, 0.92];P < .001) and participant level (AUC, 0.90 [95% CI: 0.82, 0.98] vs 0.7

关键词： Voltage   Circuits   Systolic arrays   Integrated circuit reliability   Delays   Voltage control   System-on-chip   Memory management   Complexity theory   Clocks   Accelerators   CAD   energy efficiency   reduced voltage  

摘要： Since dynamic power has a quadratic relationship with voltage, reducing voltage is an effective way to lower power consumption in digital circuits. However, maintaining stable operation at lower voltages is challenging due to increased sensitivity to process, voltage, and temperature (PVT) variations, making it difficult to determine optimal operating points using static timing analysis (STA). While circuit- and device-level solutions like timing error detection (TED) systems can enable lower voltage operation, they introduce significant overhead and design complexity. In this article, we integrate an algorithm-based fault tolerance (ABFT) method into the structure of systolic arrays (SAs) to capture timing errors when voltage is scaled down, ensuring safe and optimized low-voltage operation. Our proposed approach, SCISSORS, demonstrates how extra voltage margins in SAs used for matrix arithmetic can be trimmed by integrating a simple algorithmic technique into the structure of the array. This solution not only detects errors in the accelerator but also those caused by voltage reduction in on-chip memory and auxiliary circuits. It is fully implementable through hardware description languages (HDL) without requiring transistor- or circuit-level modifications to the netlist. Implementation on a Zynq system-on-chip (SoC) shows that SCISSORS introduces only a tolerable overhead of 11% and 8% for 32x32 and 64x64 SAs, respectively, while achieving nearly a 2x improvement in energy efficiency. Experimental results further demonstrate that SCISSORS adaptively adjusts voltage in response to the voltage-temperature coupling behavior of digital circuits at runtime, specifically addressing inverse temperature dependence (ITD).

关键词： Arterial dissection   Migraine   Stroke  

关键词： Coronary artery disease   Plaque   Atherosclerotic   Computed tomography angiography   Radiologists  

摘要： Objectives: To evaluate the reporting trends and clinical impact of the CAD-RADS modifier high-risk plaque (HRP). Materials and methods: Radiology reports of cardiac CT angiography performed in a tertiary referral hospital between October 2017 and December 2021 were retrospectively reviewed. Cases coded with modifier HRP or with CT reports mentioning HRP were defined as "HRP-reported." The prevalence of HRP-reported cases was analyzed. Subsequent management within 90 days post-CT was reviewed for cases with suspected stable angina. Results: Among the 21503 cases (mean age, 62.7 years +/- 12.3 [SD];11,127 men) enrolled, 169 cases (0.8%) were HRP-reported. HRP-reported cases were more frequent in cases with suspected acute coronary syndrome or stable angina than others (1.2% vs. 1.1% vs. 0.1%;p < 0.001), protocols for coronary CT angiography or triple-rule-out CT, compared to others (1.1% vs. 0.7% vs. 0.1%;p < 0.001), and cases with higher coronary artery calcium or CAD-RADS categories (p for trends < 0.001). HRP reporting rates varied among the readers, ranging from 0.1 to 1.3%. In the setting of suspected stable angina, the HRP-reported group more frequently underwent invasive coronary angiography in CAD-RADS 1-2 (8.8% vs. 1.4%;p = 0.01), stress testing in CAD-RADS 3 (38.5% vs. 18.4%;p = 0.02), and coronary revascularization in CAD-RADS 3 (23.1% vs. 8.7%;p = 0.02) or 4-5 (75.0% vs. 54.6%;p = 0.001). Conclusion: The CAD-RADS modifier HRP impacted the management of patients with CAD. However, its reporting prevalence was low and varied depending on the readers and clinical settings.

关键词： gravitational lensing: weak   cosmological parameters   large-scale structure  

摘要： We present the first application of marked power spectra to weak lensing data, using maps from the Subaru Hyper Suprime-Cam Year 1 (HSC-Y1) survey. Marked convergence fields, constructed by weighting the convergence field with non-linear functions of its smoothed version, are designed to encode higher-order information while remaining computationally tractable. Using simulations tailored to the HSC-Y1 data, we test three mark functions that up- or down-weight different density environments. Our results show that combining multiple types of marked auto and cross-spectra improves constraints on the clustering amplitude parameter $S_8\equiv \sigma _8\sqrt{\Omega _{\rm m}/0.3}$ by $\approx$43 per cent compared to standard two-point power spectra. When applied to the HSC-Y1 data, this translates into a constraint on $S_8 = 0.807\pm 0.024$. We assess the sensitivity of the marked power spectra to systematics, including baryonic effects, intrinsic alignment, photometric redshifts, and multiplicative shear bias. We note that some of the additional information introduced by the marked field originates from scales smaller than the scale cut, and is partly Gaussian in nature. This does not invalidate our systematic tests. These results demonstrate the promise of marked statistics as a practical and powerful tool for extracting non-Gaussian information from weak lensing surveys.

关键词： Compression and extension triaxial test   Elastoplastic model   Matsuoka-Nakai criterion   Modified cam clay model   The intermediate principal stress effect  

摘要： The fundamental Cam-Clay constitutive model for soils did not include strength anisotropy in the deviatoric plane (i.e., Lode angle effects) through a modified failure criterion, so there was no difference in deviatoric stress between the compression and extension paths. However, the extension triaxial and true triaxial tests exhibit differences in shear resistance response compared to the compression path. This difference in shear stress response can impact numerical simulations because the stress paths can be uncertain throughout the domain of the simulated model. The paper presents three straightforward methods to incorporate Lode angle effects using the Matsuoka-Nakai criterion. Triaxial compression and extension tests under drained and undrained conditions were simulated. Several lessons were learned from these simulations about the ease of incorporating the Matsuoka-Nakai criterion and the differences between simulations using three methods. Finally, an extensive discussion focuses on identifying the most suitable alternative for simulating soil mechanical behavior. This discussion was intended as a simple improvement to the modified Cam Clay model for basic simulations or as a basis for further, more complex model development.

关键词： Visual explanation   Object detector   XAI   CAM-based method  

摘要： Visual explanation for object detectors is crucial for ensuring model reliability and promoting their application across a variety of domains. However, existing visual explanation methods often produce low-quality heat maps that highlight only parts of important regions for detected instances. This limitation reduces the interpretability of object detectors and hinders effective model analysis. To address this issue, we propose Spatial Sensitive Grad-CAM++, a visual explanation method for object detectors designed to enhance the quality of heat maps. The proposed method introduces a weighted combination of gradient maps into the heat map computation, taking into account the architecture of object detectors. This approach enables a more accurate representation of each CNN channel's contribution to the final heat map, resulting in high-quality heat maps that better identify important regions. In quantitative evaluations using the deletion and insertion metrics, we confirm that the proposed method outperforms existing methods by approximately 30% and 8%, respectively. In qualitative evaluations, we further demonstrate the superiority of the proposed method. These results suggest that the proposed method provides more faithful explanations, allowing for more accurate and reliable model analysis.

关键词： Image reconstruction   Detectors   Computed tomography   Imaging   Digital TV   X-ray imaging   Solid modeling   Total variance   Reconstruction algorithms   Design automation   Chambolle-Pock (CP)   computer aided design (CAD)   directional total variation (DTV)   optimization   orthogonal translation (OT) computed laminography  

摘要： The orthogonal translation (OT) computed laminography (OTCL) is suitable for 3-D high-resolution imaging of plates. However, the projection data via OT scanning is in fact limited-angle data, which will produce inter-layer aliasing artifacts in the reconstructed image. Inspired by the success of the directional total variation (DTV) algorithm in 2-D limited-angle computed tomography (CT), in this work, we propose a computer aided design (CAD) image guided DTV (CDTV) algorithm. The CDTV model is a constrained optimization model. The constraint terms are the CDTV term and DTV term, whereas the objective term is the data fidelity term. We solve this model by the use of the Chambolle-Pock (CP) algorithm. To evaluate this newly-proposed algorithm, we perform the simulation experiments and a real data experiment. The filtered back projection (FBP), simultaneous algebra reconstruction technique (SART), total variation (TV), truncated adaptive-weight TV (TAwTV), CAD prior image guided adaptive weighted high-order total variation (Cpi-awHOTV) and DTV algorithms are selected as comparison versions. Both the simulation and the real data experiments show that the CDTV algorithm can effectively suppress the aliasing artifacts and improve the layer-to-layer quality of the reconstructed images. The code for this article is publicly available at the following website: https://***/YaruiXi/CDTV-algorithm