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关键词： Dissection   Stroke   Stroke Or Other Cerebrovascular Disease  

关键词： Dissection   Pregnancy   Stroke   Thrombolysis  

关键词： Complementary FeFETs   logic-in-memory   CAM   hamming distance   few-shot learning   XOR   Complementary FeFETs   logic-in-memory   CAM   hamming distance   few-shot learning   XOR  

摘要： Classification-based learning in deep neural networks, particularly few-shot learning, demands efficient similarity metrics such as Hamming distance. Conventional architectures suffer from high energy overheads due to frequent data movement between memory and processing units, hindering scalability. In-memory computing addresses this by integrating computation within memory, yet analog-based systems rely on power-hungry analog-to-digital converters (ADCs) and face scalability challenges due to device variability, especially in emerging memories. This work presents a fully digital Ferroelectric FET (FeFET)-based Logic-in-Memory (LiM) XOR cell, designed using GlobalFoundries' 28 nm technology, eliminating ADCs and ensuring robust, energy-efficient, and scalable operation. Our 2T FeFET XOR cell, applied to 4096-bit Hamming distance calculations, achieves 23 x lower energy, 3x faster latency, and 14 x area reduction over state-of-the-art designs. Delivering 2337 Gsamples/(s & sdot;W & sdot;mm(2)) - a 300x improvement - this architecture offers a compelling solution for energy-efficient, reliable, and scalable AI hardware, driving sustainable computing.

关键词： Functional estimation   minimax optimality   convex optimization and duality   modulus of continuity   linear programming  

摘要： Le Cam's method (or the two-point method) is a commonly used tool for obtaining statistical lower bound and especially popular for functional estimation problems. This work aims to explain and give conditions for the tightness of Le Cam's lower bound in functional estimation from the perspective of convex duality. Under a variety of settings, it is shown that the maximization problem that searches for the best two-point lower bound, upon dualizing, becomes a minimization problem minimizing an upper bound on the quadratic risk over a family of estimators. Since by the minimax theorem two problems have the same value, this value also characterizes (up to a universal factor) the optimal estimation rate. For estimating linear functionals of a distribution, our work strengthens prior results of Donoho-Liu (Ann. Statist. 19 (1991) 633-667) (for quadratic loss) by dropping the H & ouml;lderian assumption on the modulus of continuity. For exponential families, our results extend those of Juditsky-Nemirovski (Ann. Statist. 37 (2009) 2278-2300) by characterizing the minimax risk for the quadratic loss under weaker assumptions on the exponential family. We also provide an extension to the high-dimensional setting for estimating separable functionals. An application of our methodology to the area of "estimating the unseens" is provided in the companion paper (Polyanskiy and Wu (2023)), resolving the optimal rates (within logarithmic factors) of the distinct elements problem and Fisher's species problem.

关键词： automatic tooth segmentation   CAD/CAM software   digital models  

摘要： Objective: To investigate and compare the accuracy of the automatic orthodontic tooth segmentation process performed by three commercial CAD software packages. Materials and Methods: Three typodonts, representing different degrees of crowding in both arches (mild, moderate and severe), were scanned and the files imported into three professional CAD software packages (ArchForm, OrthoSystem and VISION). In addition, 28 removable teeth, used for construction of each typodont, were scanned and their STL. files used for reference purposes. After tooth segmentation, the STL. file generated for each tooth by each software was 3D-superimposed onto its reference, and measurements were analyzed for each tooth subgroup in both arches. Both 2D discrepancies at 13 different points (mm) and central mesiodistal width (mm), and 3D discrepancies in area and volume (mm3) were investigated. Tooth segmentation accuracy was compared with respect to the reference STL. files and among software packages. The amount of crowding was investigated for its influence on the tooth segmentation process. Results: Most linear and 3D measurements displayed some degree of inaccuracy, with a general tendency to oversize segmented teeth. The degree of crowding did not appear to affect the accuracy of tooth segmentation, considering both arches and each individual tooth group (p > 0.05). Different software packages performed differently, though likely not to a clinically significant degree for most of the discrepancies found. In particular, OrthoSystem and VISION demonstrated better accuracy compared to ArchForm. Conclusions: Automatic tooth segmentation software presents variable degrees of inaccuracy, irrespective of crowding severity. The different software packages evaluated demonstrated varying levels of accuracy, with no clinically significant differences among them, except in a few cases. While most single-point discrepancies can be considered clinically irrelevant (< 0.1 mm), exceptions include t

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.

关键词： breast lesions   classification   deep learning   dynamic tissue stimulation   grading   RFTSDP Method   ultrasound RF time series  

摘要： Objectives Accurate detection of breast lesion type is crucial for optimizing treatment;however, due to the limited precision of current diagnostic methods, biopsies are often required. To address this limitation, we proposed radio frequency time series dynamic processing (RFTSDP) in 2020, which analyzes the dynamic response of tissue and the impact of scatterer displacement on RF echoes during controlled stimulations to enhance diagnostic information. Methods We developed a vibration-generating device and collected ultrafast ultrasound data from 11 ex vivo breast tissue samples under different stimulations. Deep learning (DL) was used for automated feature extraction and lesion classification into 2, 3, and 5 categories. The performance of the convolutional neural network (CNN)-based RFTSDP method was compared with traditional machine learning techniques, which involved spectral and nonlinear feature extraction from RF time series, followed by a support vector machine (SVM). Results With 65 Hz vibration, the DL-based RFTSDP method achieved 99.53 +/- 0.47% accuracy in classifying and grading breast lesions. CNN consistently outperformed SVM, particularly under vibratory stimulation. In 5-class classification, CNN reached 98.01% versus 95.64% for SVM, with the difference being statistically significant (P < .05). Furthermore, the CNN-based RFTSDP method showed a 28.67% improvement in classification accuracy compared to the non-stimulation condition and the analysis of focused raw data. Conclusions We developed a DL-based CAD system capable of classifying and grading breast lesions. This study demonstrates that the proposed system not only enhances classification but also ensures increased stability and robustness compared to traditional methods.

关键词： Complementary and alternative medicine   CAM   depoliticisation   political participation   voting   survey  

摘要： The increasing cultural prevalence and appeal of complementary and alternative medicine (CAM) have raised concerns about its potential depoliticising effects. Due to its focus on the self, CAM is believed to cultivate individualism and orient transformative energies towards self-improvement rather than the collective struggle for social justice. However, despite these concerns, few quantitative studies have examined CAM from the perspective of the depoliticisation thesis. This article aims to address this gap by studying the association between political participation and CAM with data from the European Social Survey (ESS). These data enable us to capture a diverse range of CAM practices and to scrutinise both institutionalised forms of political participation, such as voting, and non-institutionalised participation taking place in civil society. Contrary to the depoliticisation thesis, our results show that CAM users either engage more actively in voting or do not significantly differ in their voting behaviour compared to non-users, depending on the specific CAM modalities considered. Moreover, CAM users participate more actively in non-institutionalised activities than non-users across all types of CAM modalities. This article offers valuable insights into the relationship between CAM and political engagement and challenges prevailing assumptions about the depoliticising effects of CAM.

关键词： Aspirin   Hazard ratio   Hemorrhage   Medical risk factors   Myocardial infarction   Percutaneous coronary intervention   Randomized trials   Secondary prevention   Stable coronary artery disease  

摘要： AbstractClinical Impact RatingsGIM/FP/GP: Cardiology: