Rapid measurement method of intracavity phase retardation based on laser frequency splitting.

We present a method for phase retardation measurement of intracavity optical elements which is based on frequency splitting caused by weak phase anisotropy of Nd: YAG. The measurement range covers 0-π and the measurement uncertainty is less than 0.0300 rad. A theoretical analysis is provided to obtain the phase retardation of intracavity optical elements by using the phase difference or frequency difference of two eigenmodes. The minimum error is 0.0036 rad by using the composite wave plate to verify various phase retardation conditions. This work provides a rapid and accurate intracavity method for measuring the phase retardation of optical elements.

[Comparison of machine learning and Logistic regression model in predicting acute kidney injury after cardiac surgery: data analysis based on MIMIC-III database].

OBJECTIVE: To establish an acute kidney injury (AKI) prediction model in patients after cardiac surgery by extreme gradient boosting (XGBoost) machine learning model, and to explore the risk and protective factors for AKI in patients after cardiac surgery. METHODS: All patients who underwent cardiac surgery in Medical Information Mart for Intensive Care-III (MIMIC-III) database were enrolled, and they were divided into AKI group and non-AKI group according to whether AKI developed within 14 days after cardiac surgery. Their clinical characteristics were compared. Based on five-fold cross-validation, XGBoost and Logistic regression were used to establish the prediction model of AKI after cardiac surgery. And the area under the receiver operator characteristic curve (AUC) of the models was compared. The output model of XGBoost was interpreted by Shapley additive explanations (SHAP). RESULTS: A total of 6 912 patients were included, of which 5 681 (82.2%) developed AKI within 14 days after the operation, and 1 231 (17.8%) did not. Compared with the non-AKI group, the main characteristics of AKI group included older age [years: 68.0 (59.0, 76.0) vs. 62.0 (52.0, 71.0)], higher incidence of emergency admission and complicated with obesity and diabetes (52.4% vs. 47.8%, 9.0% vs. 4.0%, 32.0% vs. 22.2%), lower respiratory rate [RR; bpm: times/min: 17.0 (14.0, 20.0) vs. 19.0 (15.0, 22.0)], lower heart rate [HR; bpm: 80.0 (67.0, 89.0) vs. 82.0 (71.5, 93.0)], higher blood pressure [mmHg (1 mmHg ≈ 0.133 kPa): 80.0 (70.7, 90.0) vs. 78.0 (70.0, 88.0)], higher hemoglobin (Hb), blood glucose, blood K+ level and serum creatinine [SCr; Hb (g/L): 122.0 (109.0, 136.0) vs. 120.0 (106.0, 135.0), blood glucose (mmol/L): 7.3 (6.1, 8.9) vs. 6.8 (5.7, 8.5), blood K+ level (mmol/L): 4.2 (3.9, 4.7) vs. 4.2 (3.8, 4.6), SCr (µmol/L): 88.4 (70.7, 106.1) vs. 79.6 (70.7, 97.2)], lower albumin (ALB) and triacylglycerol [TG; ALB (g/L): 38.0 (35.0, 41.0) vs. 39.0 (37.0, 42.0), TG (mmol/L): 1.4 (1.0, 2.0) vs. 1.5 (1.0, 2.2)] as well as higher incidence of multiple organ dysfunction syndrome (MODS) and sepsis (30.6% vs. 16.2%, 3.3% vs. 1.9%), with significant differences (all P < 0.05). In the output model of Logistic regression, important predictors were lactic acid [Lac; odds ratio (OR) = 1.062, 95% confidence interval (95%CI) was 1.030-1.100, P = 0.005], obesity (OR = 2.234, 95%CI was 1.900-2.640, P < 0.001), male (OR = 0.858, 95%CI was 0.794-0.928, P = 0.049), diabetes (OR = 1.820, 95%CI was 1.680-1.980, P < 0.001) and emergency admission (OR = 1.278, 95%CI was 1.190-1.380, P < 0.001). Receiver operator characteristic curve (ROC curve) analysis showed that the AUC of the Logistic regression model for predicting AKI after cardiac surgery was 0.62 (95%CI was 0.61-0.67). After optimizing the XGBoost model parameters by grid search combined with five-fold cross-validation, the model was trained well with no overfitting or overfitting. ROC analysis showed that the AUC of XGBoost model for predicting AKI after cardiac surgery was 0.77 (95%CI was 0.75-0.80), which was significantly higher than that of Logistic regression model (P < 0.01). After SHAP treatment, in the output model of XGBoost, age and ALB were the most important predictors of the final outcome, where age was the risk factor (average |SHAP value| was 0.434), and ALB was the protective factor (average |SHAP value| was 0.221). CONCLUSIONS: Age is an important risk factor for AKI after cardiac surgery, and ALB is a protective factor. The performance of machine learning in predicting cardiac and vascular surgery-associated AKI is better than the traditional Logistic regression. XGBoost can analyze the more complex relationship between variables and outcomes, and can predict the risk of postoperative AKI more accurately and individually.

Prophylactic juxtapapillary laser photocoagulation in pediatric morning glory syndrome.

AIM: To determine the anatomic and visual outcomes of prophylactic juxtapapillary laser photocoagulation treatment alone in the prevention of retinal detachment (RD) in a cohort of pediatric patients diagnosed with morning glory syndrome (MGS). METHODS: A total of 24 eyes of 22 consecutive patients aged 0-15y diagnosed with MGS treated with prophylactic juxtapapillary laser photocoagulation alone were reviewed. Data including demographics, ocular examination, anatomic and visual outcomes, following treatment and complications were collected. RESULTS: Two patients had bilateral laser treatment and 20 had monocular laser treatment. The age at treatment of 13 (59.1%) patients was less than 12mo. The presenting symptoms included strabismus (6/22, 27.3%), decreased vision (2/22, 9.1%), and routine fundus screening (14/22, 63.6%). Fifteen (68.2%) patients underwent cranial magnetic resonance imaging (MRI) examinations, and 3 of those 15 (20.0%) had abnormal findings in the nervous system. Based on preoperative wide-field fundus photography and B-scan echography, all (100.0%) eyes had no obvious RD. On postoperative 1mo and 6mo and the following follow-ups, the anatomic outcomes of all eyes remained stable. The mean follow-up duration was 27.7±17.5mo. No severe complications were found. Preoperative visual acuity acquired from 2 (9.1%) patients ranged from light perception to 20/200. Postoperative acuity acquired from 11 (50.0%) patients ranged from light perception to 20/125. CONCLUSION: The preliminary anatomic and visual outcomes of prophylactic juxtapapillary laser treatment alone in pediatric MGS patients are relatively stable in a short-term follow-up. Further long-term clinical observation will be needed to confirm its efficacy and safety.

miR-146a Inhibits Proliferation and Enhances Chemosensitivity in Epithelial Ovarian Cancer via Reduction of SOD2.

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy, accounting for 90% of all ovarian cancer. Dysregulation of miRNAs is associated with several types of EOC. In the current research, we aimed to study the role of abnormal expression of miR-146a in the development of EOC and to elucidate the possible molecular mechanisms. Compared with control samples, mRNA expression of miR-146a was significantly decreased in EOC tissues and cell lines. Overexpression of miR-146a prohibited cell proliferation, enhanced apoptosis, and increased sensitivity to chemotherapy drugs in EOC cells. In contrast, downregulation of miR-146a promoted cell proliferation, suppressed apoptosis, and decreased sensitivity to chemotherapy drugs in EOC cells. Overexpression of miR-146a increased the reactive oxygen species (ROS) level and decreased SOD2 mRNA and protein expression. Downregulation of miR-146a increased SOD2 mRNA and protein expression. Overexpression of SOD2 significantly inhibited miR-146a mimics-induced suppression of cell proliferation and the increase of apoptosis and chemosensitivity. In conclusion, we identify miR-146a as a potential tumor suppressor in patients with EOC. miR-146a downregulates the expression of SOD2 and enhances ROS generation, leading to increased apoptosis, inhibition of proliferation, and enhanced sensitivity to chemotherapy. The data demonstrate that the miR-146a/SOD2/ROS pathway may serve as a novel therapeutic target and prognostic marker in patients with EOC.