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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： Conjugate cams   clearance collisions   lubrication   cam wear   dynamic characteristics  

摘要： Conjugate cams are widely used in the beating-up mechanism of modern high-speed rapier looms, and the collision and friction between the cams and rollers significantly impact the service life of the cams. To investigate the relationships among cam rotation speed, clearance collision, and lubrication wear, the conjugate cam beating-up mechanism was selected as the research object. A dynamic model for clearance collision of conjugate cam pairs was established, and cam wear under different working conditions was simulated and calculated based on the Archard adhesion wear model. The research results indicate that as the driving speed increases, the cam impact force also increases accordingly, leading to increased cam wear. Additionally, an increase in cam clearance can raise the peak contact load between the cam and the roller, resulting in an increase in the peak depth of cam wear. By establishing a model and comprehensively analyzing the effects of speed and clearance, important theoretical basis is provided for predicting and enhancing the service life of conjugate cams.

关键词： drive cycles   electric vehicles (EVs)   induction machine (IM)   interior permanent magnet synchronous machine (i-PMSM)   steady state thermal analysis   transient thermal analysis  

摘要： A comparative thermal performance study is carried out on an induction machine (IM) and an interior permanent magnet synchronous machine (i-PMSM) for electric vehicle applications under the standardized Highway Fuel Economy Test (HWFET) and Worldwide Harmonized Light Vehicles Test Procedure (WLTP) Class 3 drive cycles, using ANSYS Motor-CAD in this paper. To allow a fair comparison of steady state and transient thermal behavior, identical cooling boundary conditions were set while considering a consistent electromagnetic thermal modeling framework. The results show that i-PMSM has lower total losses (2.265 kW) than the IM (3.37 kW) under representative drive cycle operating conditions, since there are no rotor copper losses involved. In the case of operation during WLTP Class 3, peak stator winding temperatures reached 173.3 degrees C and 133.6 degrees C for the IM and i-PMSM, respectively, with substantially larger thermal stresses in the IM. From this, it can be seen that the transient thermal response exhibited by i-PMSM was much smoother, with reduced temperature oscillations under dynamic loading, whereas the thermal fluctuation of the IM was significant during frequent acceleration and deceleration events. Although peak efficiency regions above 97% have been observed in both machines at specific torque-speed combinations, drive-cycle-integrated loss behavior has shown that i-PMSM maintains lower overall thermal burden across the investigated operating conditions. These findings consequently bring to the fore the importance of drive cycle dependent thermal evaluation in electric vehicle motor selection and reveal that while the IM has strong benefits regarding robustness and cost, i-PMSM will have superior thermal efficiency and stability during realistic driving scenarios. The presented comparative framework offers practical insights into traction motor design and technology selection in electric vehicle applications.

关键词： Endocrown   CAD-CAM   3D printing   Fracture resistance  

摘要： Introduction This study aimed to compare the fracture resistance of leucite reinforced glass ceramic (LRC), resin nanoceramic (RNC), lithium disilicate ceramic (LDS) blocks, and printable resin (PRM) used in the production of ferrulated and non-ferrulated endocrowns for mandibular molars. Methods A total of 108 extracted mandibular molars with homogeneous dimensions and free of fractures, cracks, or caries were included. Root canal treatment was performed using the ProTaper Next rotary file system, and canals were obturated with gutta-percha and epoxy resin sealer by the lateral compaction technique. Specimens were divided into ferrule (F;1-mm ferrule height), non-ferrule (NF), and control groups. Digital impressions were obtained with an intraoral scanner (Cerec Primescan), and restorations were designed in CAD software (inLab CAD SW 22.4). Based on restorative materials, groups were classified as follows: LRC, RNC, LDS, and PRM for both F and NF groups, in addition to a control group of intact teeth. Restorations were fabricated either by milling (LRC, RNC, LDS) or 3D printing (PRM), and surface conditioning was performed according to manufacturers' instructions. All restorations were cemented using a universal adhesive system and dual-cure resin *** resistance was tested in a universal testing machine (Instron, USA) at a crosshead speed of 1 mm/min until fracture occurred, and failure modes were classified as Type I (restoration fracture), Type II (restorable fracture involving tooth and restoration), or Type III (non-restorable fracture of tooth structure). Statistical analyses were performed using SPSS v23, with significance set at P < .05. Results Fracture resistance values varied significantly among restorative materials (P < .05);intact teeth exhibited the highest resistance, while LRC restorations showed the lowest. PRM, RNC, and LDS restorations demonstrated significantly higher resistance than LRC, and all endocrown groups exceeded maximum mas

关键词： Dissection   Pregnancy   Stroke   Thrombolysis  

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： climate anxiety   climate change   eco-anxiety   individual differences   mental health   situated assessment method  

摘要： Although increasing research examines climate anxiety, little is known about the situational factors related to it. To assess these factors, we developed and evaluated a situated psychometric instrument for assessing how much climate anxiety individuals recall experiencing in 31 situations where climate anxiety is likely (e.g., hearing about climate catastrophes on the news). Of interest was how climate anxiety is experienced in a country like the UK, where climate disasters are mostly heard about in the media and anticipated in the future, relative to countries where climate disasters are experienced directly and regularly. In an online survey (N = 303;50.8% female), we investigated how much climate anxiety individuals recall experiencing in situations where climate anxiety is likely to occur, along with how much they recall experiencing 13 factors potentially related to climate anxiety (e.g., threat, violation, rumination). An individual measure of climate anxiety, averaged across situations, exhibited high reliability, construct validity and content validity. Climate anxiety varied widely across situations, with individuals further varying in how much climate anxiety they remembered experiencing in each situation. As predicted, the 13 situational factors tended to correlate significantly with climate anxiety across situations, explaining a median 75% of its variance in individual regressions.