Structural changes in the left atrium (LA) modestly predict outcomes in patients undergoing catheter ablation for atrial fibrillation (AF). Machine learning (ML) is a promising approach to ...personalize AF management strategies and improve predictive risk models after catheter ablation by integrating atrial geometry from cardiac computed tomography (CT) scans and patient-specific clinical data. We hypothesized that ML approaches based on a patient's specific data can identify responders to AF ablation.
Consecutive patients undergoing AF ablation, who had preprocedural CT scans, demographics, and 1-year follow-up data, were included in the study for a retrospective analysis. The inputs of models were CT-derived morphological features from left atrial segmentation (including the shape, volume of the LA, LA appendage, and pulmonary vein ostia) along with deep features learned directly from raw CT images, and clinical data. These were merged intelligently in a framework to learn their individual importance and produce the optimal classification.
Three hundred twenty-one patients (64.2 ± 10.6 years, 69% male, 40% paroxysmal AF) were analyzed. Post 10-fold nested cross-validation, the model trained to intelligently merge and learn appropriate weights for clinical, morphological, and imaging data (AUC 0.821) outperformed those trained solely on clinical data (AUC 0.626), morphological (AUC 0.659), or imaging data (AUC 0.764).
Our ML approach provides an end-to-end automated technique to predict AF ablation outcomes using deep learning from CT images, derived structural properties of LA, augmented by incorporation of clinical data in a merged ML framework. This can help develop personalized strategies for patient selection in invasive management of AF.
Constipation is a common intestinal disease. Kiwi berries can effectively prevent constipation. However, studies have yet to be done to determine how kiwi berries prevent constipation. For 2 weeks, ...mice in this study were continually orally gavaged with kiwi berry, loperamide, or a combination of the two. This study found that the kiwi group's feces had more water than the constipated mice. In addition, kiwi berries can speed up gastrointestinal transit (GI), shorten the time it takes to pass the first dark stool, and dramatically enhance body weight gain. In the interstitial cells of Cajal (ICC) cells and colon tissues, alterations in the protein expression of vasoactive intestinal peptide (VIP), cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), and aquaporin-3 (AQP3) were found. At 3, 6, and 12 h of ICC cells and mouse colon, the kiwi group’s VIP, cAMP, PKA, and AQP3 protein expression levels were lower than those of the constipated mice. The kiwi berry can decrease the Firmicutes to Bacteroidetes ratio and boost the diversity and quantity of gut microbiota. By influencing the gut microbiota and VIP-cAMP-PKA-AQP3 signaling pathway, kiwi berries prevent constipation.
Abstract In spin wave (SW) devices, the modulation of SWs for computational units is necessary, imposing extremely high demands on material systems. In this study, high‐quality epitaxial‐grown spinel ...γ‐Fe 2 O 3 thin films on conductive Nb‐doped SrTiO 3 substrates, achieving fast‐speed, high‐frequency, and long‐distance SW propagation in this ferrimagnetic material, are developed. A novel two‐step film growth technique using pulsed laser deposition is proposed and optimized, and the damping constant, exchange stiffness, and anisotropies of γ‐Fe 2 O 3 are determined. Compared to reported semiconductor magnetic materials, these epitaxial‐grown γ‐Fe 2 O 3 thin films exhibit a significantly lower damping constant of 10 −2 , representing a substantial advancement. Using finite‐difference calculations, SW propagation is simulated, and vital information on transmission distance and dispersion curves is obtained. Experimental results show excellent agreement with these simulations. By applying a voltage to both sides of the conducting substrate, current across the film and SW device, resulting in the frequency shift of the SWs, is generated. These results demonstrate that high‐quality γ‐Fe 2 O 3 films developed through the two‐step growth method can efficiently propagate SWs, offering possibilities for various modulation methods in SW‐based computing devices. This study positions spinel γ‐Fe 2 O 3 as a promising ferrimagnetic candidate for future applications in efficient SW modulation within computational systems.
Although chiral semiconductors have shown promising progress in direct circularly polarized light (CPL) detection and emission, they still face potential challenges. A chirality‐switching mechanism ...or approach integrating two enantiomers is needed to discriminate the handedness of a given CPL; additionally, a large material volume is required for sufficient chiroptical interaction. These two requirements pose significant obstacles to the simplification and miniaturization of the devices. Here, room‐temperature chiral polaritons fulfilling dual‐handedness functions and exhibiting a more‐than‐two‐order enhancement of the chiroptical signal are demonstrated, by embedding a 40 nm‐thick perovskite film with a 2D chiroptical effect into a Fabry–Pérot cavity. By mixing chiral perovskites with different crystal structures, a pronounced 2D chiroptical effect is accomplished in the perovskite film, featured by an inverted chiroptical response for counter‐propagating CPL. This inversion behavior matches the photonic handedness switch during CPL circulation in the Fabry–Pérot cavity, thus harvesting giant enhancement of the chiroptical response. Furthermore, affected by the unique quarter‐wave‐plate effects, the polariton emission achieves a chiral dissymmetry of ±4% (for the emission from the front and the back sides). The room‐temperature polaritons with the strong dissymmetric chiroptical interaction shall have implications on a fundamental level and future on‐chip applications for biomolecule analysis and quantum computing.
The light–matter interaction between a 2D chiroptical film and a Fabry–Pérot cavity is investigated. The chiroptical response inversion of the 2D chiroptical film shall be ideally suited to the circularly polarized light switching feature in the Fabry–Pérot cavity, resulting in the enhancement effect in the chiroptical signal.
Labeled data is a critical resource for training and evaluating machine learning models. However, many real-life datasets are only partially labeled. We propose a semi-supervised machine learning ...training strategy to improve event detection performance on sequential data, such as video recordings, when only sparse labels are available, such as event start times without their corresponding end times. Our method uses noisy guesses of the events' end times to train event detection models. Depending on how conservative these guesses are, mislabeled samples may be introduced into the training set. We further propose a mathematical model for explaining and estimating the evolution of the classification performance for increasingly noisier end time estimates. We show that neural networks can improve their detection performance by leveraging more training data with less conservative approximations despite the higher proportion of incorrect labels. We adapt sequential versions of CIFAR-10 and MNIST, and use the Berkeley MHAD and HMBD51 video datasets to empirically evaluate our method, and find that our risk-tolerant strategy outperforms conservative estimates by 3.5 points of mean average precision for CIFAR, 30 points for MNIST, 3 points for MHAD, and 14 points for HMBD51. Then, we leverage the proposed training strategy to tackle a real-life application: processing continuous video recordings of epilepsy patients, and show that our method outperforms baseline labeling methods by 17 points of average precision, and reaches a classification performance similar to that of fully supervised models. We share part of the code for this article at the following repository: fpgdubost/CIFAR-10-Sparsely-Labeled-Sequential-Data.
To improve the quality of modern life in the current society, low-power, highly sensitive, and reliable healthcare technology is necessary to monitor human health in real-time. In this study, we ...fabricated partially suspended monolayer graphene surface acoustic wave gas sensors (G-SAWs) with a love-mode wave to effectively detect ppt-level acetone gas molecules at room temperature. The sputtered SiO
2
thin film on the surface of a black 36°YX-LiTaO
3
(B-LT) substrate acted as a guiding layer, effectively reducing the noise and insertion loss. The G-SAWs exhibited enhanced gas response towards acetone gas molecules (800 ppt) in a real-time atmosphere. The high sensitivity of the G-SAW sensor can be attributed to the elasticity and surface roughness of the SiO
2
film. In addition, the G-SAW sensor exhibited rapid response and recovery at room temperature. This study provides a potential strategy for diagnosing different stages of diabetes in the human body.
To improve the quality of modern life in the current society, low-power, highly sensitive, and reliable healthcare technology is necessary to monitor human health in real-time.
Hydrogen bond (H‐bond) plays an important role in structure evolution and properties of various polymers. Due to directivity and saturation of H‐bond, its formation is influenced by macromolecular ...chain conformation but the relationship is still not well understood up to now. In this paper, amorphous models of polyamide 66 (PA66), polyamide 6T (PA6T), and poly(p‐phenylene‐terephthamide) (PPTA) are built to study influence of chain rigidity on H‐bonding formation by utilizing Molecular Dynamics simulation. Compared with PA66 and PA6T, it is found that chain rigidity of PPTA is more remarkable and corresponding conformation adjustment is hindered more significantly, which leads to considerable weak H‐bonds and free H‐bonding sites. After introducing benzimidazole moiety into PPTA, more H‐bonds form due to more potential H‐bonding sites in benzimidazole units. However, the newly added H‐bonding donor and acceptor are in the co‐ring, and there is a high rotational energy barrier for benzimidazole ring, both of which hinder the formation of strong H‐bonds. Therefore, a strategy is proposed to fill free H‐bonding sites in rigid‐chain polymers through adding oligomers with high movement ability. Thus, the H‐bonds in rigid‐chain polymers are effectively enhanced due to bridging effect of oligomers and tensile modulus of the aramid is improved significantly.
The formation mechanism of free H‐bonding sites between rigid chains is explored by Molecular Dynamics simulation. The conformation adjustment of rigid chain is hindered due to large chain rigidity and high energy barrier. Oligomers possessing strong ability in chain movement are added in rigid‐chain polymers and thus H‐bonding strength is enhanced by bridging effect of oligomers.
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