Groundwater nitrate contamination poses a potential threat to human health and environmental safety globally. This study proposes an interpretable stacking ensemble learning (SEL) framework for enhancing and interpreting groundwater nitrate spatial predictions by integrating the two-level heterogeneous SEL model and SHapley Additive exPlanations (SHAP). In the SEL model, five commonly used machine learning models were utilized as base models (gradient boosting decision tree, extreme gradient boosting, random forest, extremely randomized trees, and k-nearest neighbor), whose outputs were taken as input data for the meta-model.
View Article and Find Full Text PDFNitrate pollution in groundwater, which is an international problem, threatens human health and the environment. It could take decades for nitrate to transport in the groundwater system. When understanding the impacts of this nitrate legacy on water quality, the nitrate transport velocity (v) in the unsaturated zone (USZ) is of great significance.
View Article and Find Full Text PDFThe purpose of this study was to determine whether combining different testing modalities namely beta-hexosaminidase A (HEXA) enzyme analysis, HEXA DNA common mutation assay, and HEXA gene sequencing could improve the sensitivity for carrier detection in non-Ashkenazi (AJ) individuals. We performed a HEXA gene sequencing assay, a HEXA DNA common mutation assay, and a HEXA enzyme assay on 34 self-reported Tay-Sachs disease (TSD) carriers, six late-onset patients with TSD, and one pseudodeficiency allele carrier. Sensitivity of TSD carrier detection was 91% for gene sequencing compared with 91% for the enzyme assay and 52% for the DNA mutation assay.
View Article and Find Full Text PDFPurpose: To develop a high-throughput, automated, accurate method suitable for population-based carrier detection of fragile X syndrome.
Methods: We developed a new method called capillary Southern analysis that allows automated high-throughput screening for expanded fragile X mental retardation 1 (FMR1) alleles. Initially samples are analyzed by a multiplex polymerase chain reaction that contains an internal control to establish gender.