Search

Quasi-bound states in the continuum (quasi-BICs) offer unique advantages in enhancing nonlinear optical processes and advancing the development of active optical devices. Here, the tunable robust quasi-BICs resonances are experimentally achieved through the engineering of multiple-hole Si-metasurface. Notably, the quasi-BICs mode exhibits flat bands with minimal dispersion at a wide range of incident angles, as demonstrated by the angle-resolved spectroscopy measurements. Furthermore, we demonstrate a giant second-harmonic generation (SHG) enhancement by coupling a WSe2 monolayer to the quasi-BICs hosted in the metasurface. Leveraging the strong local electric field and high state density of the observed quasi-BICs, the SHG from the WSe2 monolayer can be enhanced by more than two orders of magnitude. Our work paves the way for effectively enhancing nonlinear optical processes in two dimensional (2D) materials within the framework of silicon photonics and is expected to be applied in nonlinear optical devices.

The FT4-to-FT3 ratio (FFR) variations in patients with subacute combined spinal cord degeneration (SCSD) as a potentially useful prognostic indicator are still unknown. This study aimed to investigate the changes of FFR as a potentially valuable prognostic predictor in patients with SCSD.

Abstract Background Dementia care is challenging due to the divergent trajectories in disease progression and outcomes. Predictive models are needed to flag patients at risk of near-term mortality and identify factors contributing to mortality risk across different dementia types. Methods Here, we developed machine-learning models predicting dementia patient mortality at four different survival thresholds using a dataset of 45,275 unique participants and 163,782 visit records from the U.S. National Alzheimer’s Coordinating Center (NACC). We built multi-factorial XGBoost models using a small set of mortality predictors and conducted stratified analyses with dementiatype-specific models. Results Our models achieved an area under the receiver operating characteristic curve (AUC-ROC) of over 0.82 utilizing nine parsimonious features for all 1-, 3-, 5-, and 10-year thresholds. The trained models mainly consisted of dementia-related predictors such as specific neuropsychological tests and were minimally affected by other age-related causes of death, e.g., stroke and cardiovascular conditions. Notably, stratified analyses revealed shared and distinct predictors of mortality across eight dementia types. Unsupervised clustering of mortality predictors grouped vascular dementia with depression and Lewy body dementia with frontotemporal lobar dementia. Conclusions This study demonstrates the feasibility of flagging dementia patients at risk of mortality for personalized clinical management. Parsimonious machine-learning models can be used to predict dementia patient mortality with a limited set of clinical features, and dementiatype-specific models can be applied to heterogeneous dementia patient populations.

In order to explore the differences of microstructure，composition and performances of different fatty acid salt superhydrophobic coatings，three kinds of fatty acid salt superhydrophobic coatings were prepared by electrodeposition on rough surface of TC4 alloy.The microstructure，chemical composition，phase and wettability of such superhydrophobic coatings were characterized and analyzed by scanning electron microscopy，X-ray diffraction，X-ray photoelectron spectroscopy，Fourier transform infrared spectroscopy and contact angle tester.The wear resistance，heat resistance and corrosion resistance of the superhydrophobic coatings were investigated by linear friction test，long time heating experiment and electrochemical experiment respectively.Results showed that fatty acid salt coatings obtained by anodic and cathodic deposition both had non-adhesion superhydrophobicity.The surface color and state of the three fatty acid salt coatings were different，but the micromorphology was all ＂cauliflower＂ cluster，and there was an obvious micro nano hierarchical structure.The wear resistance and heat resistance of the three superhydrophobic coatings were different due to different fatty acid salts.Corrosion resistance of three superhydrophobic coatings was better than that of the substrate.CSHS-Cu had the best corrosion resistance.The Jcorr of CSHS-Cu was 1/5 of that of the bare substrate，and its Rct was 25 times that of the bare substrate.

Background Noninvasive positive pressure ventilation (NPPV) is a major respiratory support technique for patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and carbon dioxide (CO2) retention. However, the obvious dead space in available masks used for NPPV could easily lead to repeated CO2 inhalation, which affects the correction of CO2 retention. Objective To develop a face mask with two channel and constant leakage (TCCL) used for NPPV, and to examine its value in NPPV treatment of AECOPD patients with CO2 retention. Methods Thirty patients with AECOPD and typeⅡ respiratory failure treated with NPPV were recruited from the ICU, the First Affiliated Hospital of Chongqing Medical University from 2020 to 2021, and equally randomized into an experimental group (using the TCCL mask) and an control group (using the traditional mask with an exhalation valve on the side for NPPV) . Treatment effectiveness was assessed using arterial partial pressure of oxygen (PaO2) and partial pressure of carbon dioxide (PaCO2) monitored at baseline, and at the end of 4, 8, 24, and 48 hours of NPPV treatment as well as 24 hours after NPPV cessation. Results The two-way repeated measures ANOVA indicated that treatment time and treatment approach had no interactive effects on PaO2 (P>0.05) . Treatment time produced significant main effects on PaO2 (P0.05) . Treatment time and treatment approach had no interactive effects on PaCO2 (P>0.05) . Treatment time produced significant main effect on PaCO2 (P