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Droughts present substantial challenges to agriculture, food security, and water resources. Employing a drought index based on soil moisture dynamics is a common and effective approach for agricultural drought monitoring. However, the precision of a drought index heavily relies on accurate soil moisture and soil hydraulic parameters. This study leverages remote sensing soil moisture data from the Climate Change Initiative (CCI) series products and model-generated soil moisture data from the Variable Infiltration Capacity (VIC) model. The extended triple collocation (ETC) method was applied to merge these datasets from 1992 to 2018, resulting in enhanced accuracy by 28% and 15% compared to the CCI and VIC soil moisture, respectively. Furthermore, this research establishes field capacity and a wilting point map using multiple soil datasets and pedotransfer functions, facilitating the development of an enhanced Soil Water Deficit Index (SWDI) based on merged soil moisture, field capacity, and wilting points. The findings reveal that the proposed enhanced SWDI achieves a higher accuracy in detecting agricultural drought events (probability of detection = 0.98) and quantifying their severity (matching index = 0.33) compared to an SWDI based on other soil moisture products. Moreover, the enhanced SWDI exhibits superior performance in representing drought-affected crop areas (correlation coefficient = 0.88), outperforming traditional drought indexes such as the Standardized Precipitation Index (correlation coefficient = 0.51), the Soil Moisture Anomaly Percent Index (correlation coefficient = 0.81), and the Soil Moisture Index (correlation coefficient = 0.83). The enhanced SWDI effectively captures the spatiotemporal dynamics of a drought, supporting more accurate agricultural drought monitoring and management strategies. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study. Objectives: To develop machine learning (ML) models to predict recurrent lumbar disc herniation (rLDH) following percutaneous endoscopic lumbar discectomy (PELD). Methods: We retrospectively analyzed 1159 patients who had undergone single-level PELD for lumbar disc herniation (LDH) between July 2014 to December 2019 at our institution. Various preoperative imaging variables and demographic metrics were brought in analysis. Student's t test and Chi-squared test were applied for univariate analysis, which were feature selection for ML models. We established ML models to predict rLDH: Artificial neural networks (ANN), Extreme Gradient Boost classifier (XGBoost), KNeighborsClassifier (KNN), Decision tree classifier (Decision Tree), Random forest classifier (Random Forest), and support vector classifier (SVC). Results: A total 130 patients (11.22%) were diagnosed as rLDH in 1159 patients. Recurrence occurred within 10.25 ± 11.05 months. Body mass index (BMI) (P =.027), facet orientation (FO) (P <.001), herniation type (P =.012), Modic changes (P =.004), and disc calcification (P =.013) are significant factors in univariate analysis (P <.05). Extreme Gradient Boost classifier, Random Forest, ANN showed fine area under the curve,.9315,.9220, and.8814 respectively. Conclusion: We developed a deep learning and 2 ensemble models with fine performance in prediction of rLDH following PELD. Predicting re-herniation before surgery has the potential to optimize decision-making and meaningfully decrease the rates of rLDH following PELD. Our ML model identified higher BMI, lower FO, Modic changes, disc calcification in a non-protrusive region, and herniation type (noncontained herniation) as significant features for predicting rLDH. [ABSTRACT FROM AUTHOR]

Background In this study, we investigate the effect of simultaneous fusion of preexisting adjacent spinal canal stenosis on the outcome of patients with lumbar spondylolisthesis. Methods Patients with lumbar spondylolisthesis who underwent transforaminal lumbar interbody fusion (TLIF) from August 2013 to March 2016 were included. The inclusion criteria were the following: single-level spondylolisthesis (L4 or L5) and mild to moderate spinal stenosis at cranial adjacent segment of the spondylolisthesis segment before operation. According to whether the adjacent stenotic segment was included in the scope of surgery, the patients were divided into two groups: group A, only the spondylolisthesis was treated with single-level TLIF, and the adjacent stenosis was not treated with any surgery; In group B, TLIF were performed in the spondylolisthesis segment and the adjacent stenotic level; no spinal stenosis was found in other levels. The patients were followed up for more than 5 years. The general information before operation, visual analog scale (VAS) scores of low back pain and leg pain, and Oswestry disability index (ODI) scores before operation and at the last follow-up were recorded. Results A total of 23 patients were included in group A, and 24 patients were included in group B. There was no significant difference between the two groups in gender distribution, age, course of disease, level of slippage, length of stay, degree of spondylolisthesis, stenotic grade of adjacent segment, and intervertebral disk degeneration grade (p > 0.05). The blood loss during surgery in group B was significantly higher than that in group A (p < 0.05). The operation time of group B was longer than that of group A, but the difference was not statistically significant (p = 0.245). There was no significant difference in preoperative VAS and ODI scores between the two groups. At the last follow-up, the VAS scores of low back pain in the two groups were almost the same. However, the VAS scores of leg pain and ODI scores in group B were slightly higher than those in group A at the last follow-up, but the difference was not statistically significant (p > 0.05). If relatives and friends have the similar disease, all the patients of group A and 87.5% of patients in group B would recommend that type of surgery. The satisfaction of group A (100%) was higher than that of group B (79.17%), but the difference was not statistically significant (p = 0.068). Conclusions For single-level lumbar spondylolisthesis with mild to moderate spinal stenosis in adjacent segment before operation, decompression and fusion on the level of spondylolisthesis only is a safe, less invasive, and economical surgical option, with good long-term clinical efficacy and high satisfaction rates. [ABSTRACT FROM AUTHOR]