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The Sc3+ ions doped NaYF4: Yb3+, Er3+ upconversion (UC) nanoparticles are synthesized by thermal decomposition method. We successfully obtained the upconversion luminescence (UCL) nanoparticles from green emission to red emission through doping Sc3+ ions with different concentrations. Based on the XRD, the phase change process of Sc3+ ions doped NaYF4 nanocrystalline phase were demonstrated. More importantly, through the analysis of UC spectrum data, the change in the phase of the NaY/ScF4: Yb3+, Er3+ nanocrystalline corresponds to the change in its luminous properties. It determines that the change of crystal field will lead to the change of luminescence, and then modulate the luminescence. NaScF4: Yb3+, Er3+ UC nanoparticles exhibit strong red light emission. In addition, the temperature-sensitive properties of the optimal doping concentration of Sc3+ ion were tested. The sensitivity of NaYF4: Yb3+, Er3+ nanoparticles doped with Sc3+ ion reached the maximum value of 0.024 K− 1 at 498 K. The nanocrystalline has great application value in the fields of optical temperature measurement, biomedicine, bioprobes and colorful display. [ABSTRACT FROM AUTHOR]

Today's major global pandemic, COVID-19, is caused by coronavirus disease. Every day, a large number of people all over the world become infected with this virus, and many of these individuals die from it. Diagnosing and treating this virus as soon as possible is essential due to its highly infectious nature. This study uses deep learning networks to automatically diagnose COVID-19 from chest X-ray pictures. To enhance the effectiveness of the deep learning network in this study, we suggest combining convolutional networks with type-2 fuzzy activation functions. A generative adversarial network has also been used to increase the amount of data. Based on the classification of three groups of healthy, COVID-19, and pneumonia states, 99.45% accuracy was achieved. Furthermore, the suggested method has demonstrated a sensitivity and specificity of 100 and 99%, respectively, compared to recent studies; this is a remarkable result in terms of specificity, accuracy, and sensitivity. The obtained results (irrespective of the activation functions used) confirm that our method has outperformed state-of-the-art methods used for COVID-19 classification. [ABSTRACT FROM AUTHOR]

Purpose: The effect of pretreatment infarct location on clinical outcome after successful mechanical thrombectomy is not understood. Our aim was to evaluate the association between computed tomography perfusion (CTP)-based ischemic core location and clinical outcome following excellent reperfusion in late time windows. Methods: We retrospectively reviewed patients who underwent thrombectomy for acute anterior circulation large vessel occlusion in late time windows from October 2019 to June 2021 and enrolled 65 patients with visible ischemic core on admission CTP who had received excellent reperfusion (modified thrombolysis in cerebral infarction grade 2c/3). Poor outcome was defined as a modified Rankin scale score of 3–6 at 90 days. The ischemic core infarct territories were classified into the cortical and subcortical areas. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were used in this study. Results: Of the 65 patients analyzed, 38 (58.5%) had a poor outcome. Multivariable logistic analysis showed that the subcortical infarcts (OR 11.75; 95% CI 1.79–77.32; P = 0.010) and their volume (OR 1.17; 95% CI 1.04–1.32; P = 0.011) were independently associated with poor outcome. The ROC curve indicated the capacity of the subcortical infarct involvement (areas under the curve (AUC) = 0.65; 95% CI, 0.53–0.77, P < 0.001) and subcortical infarct volume (AUC = 0.72; 95% CI, 0.60–0.83, P < 0.001) in predicting poor outcome accurately. Conclusion: Subcortical infarcts and their volume on admission CTP are associated with poor outcome after excellent reperfusion in late time windows, rather than cortical infarcts. [ABSTRACT FROM AUTHOR]

Purpose: Before we enter the era of flow diverter stents (FDS), the standard stent-assisted coiling technique is a well-established treatment option for routine paraclinoid aneurysms. We assess the clinical safety and efficacy of stent-assisted coiling with open-cell stent in the treatment of paraclinoid aneurysms and evaluate the association between clinical factors and follow-up aneurysm occlusion. Methods: The clinical and radiographic data of 110 consecutive patients with 122 paraclinoid aneurysms treated with open-cell stent between April 2015 and April 2019 were analyzed retrospectively at our center. We assessed the immediate and progressive occlusion rates, complications, and clinical outcome. Multivariate analysis was performed to investigate the risk factors of angiographic incomplete occlusion. Results: Among 110 patients, stent-assisted coiling was successfully performed in all cases. Four (3.6%) thromboembolic events were reported during the procedure, which resulted in transient morbidity. Immediate angiography demonstrated complete occlusion in 64 (52.5%) aneurysms and no occlusion of ophthalmic artery. Angiographic follow-up at 6 months demonstrated an increase in the complete occlusion rate to 92.9%. No delayed in-stent stenosis was observed, and three aneurysms recurred. Clinical follow-up was completed in 102 patients (92.7%), and favorable outcomes were achieved in 101 (99%) patients at 6 months. Multivariate analysis showed that aneurysm size (p < 0.001) was associated with incomplete aneurysm occlusion at follow-up. Conclusion: Stent-assisted coil embolization with open-cell stents is safe and effective for the treatment of paraclinoid aneurysms and provides progressive occlusion without significant in-stent stenosis events. [ABSTRACT FROM AUTHOR]