Machine-Learning Classification of Soil Bulk Density in Salt Marsh Environments.

Remotely sensed data from both in situ and satellite platforms in visible, near-infrared, and shortwave infrared (VNIR-SWIR, 400-2500 nm) regions have been widely used to characterize and model soil properties in a direct, cost-effective, and rapid manner at different scales. In this study, we assess the performance of machine-learning algorithms including random forest (RF), extreme gradient boosting machines (XGBoost), and support vector machines (SVM) to model salt marsh soil bulk density using multispectral remote-sensing data from the Landsat-7 Enhanced Thematic Mapper Plus (ETM+) platform. To our knowledge, use of remote-sensing data for estimating salt marsh soil bulk density at the vegetation rooting zone has not been investigated before.

A pathway of global food supply adaptation in a world with increasingly constrained groundwater.

Many of the world's major freshwater aquifers are being exploited unsustainably, with some projected to approach environmentally unsafe drawdown limits within the 21st century. Given that aquifer depletion tends to occur in important crop producing regions, the prospect of running dry poses a significant threat to global food security. Here we use the Global Change Assessment Model (GCAM) to explore the response of land use and agriculture sectors to severe constraints on global water resources.

Mesoscale Fracture Analysis of Multiphase Cementitious Composites Using Peridynamics.

Concrete is a complex heterogeneous material, and thus, it is important to develop numerical modeling methods to enhance the prediction accuracy of the fracture mechanism. In this study, a two-dimensional mesoscale model is developed using a non-ordinary state-based peridynamic (NOSBPD) method. Fracture in a concrete cube specimen subjected to pure tension is studied.

Hyperbaric oxygen therapy improves early posttransplant islet function.

Objective: This study investigates the therapeutic potential of hyperbaric oxygen therapy (HBO) in reducing hypoxia and improving engraftment of intraportal islet transplants by promoting angiogenesis.

Methods: Diabetic BALB/c mice were transplanted with 500 syngeneic islets intraportally and received six consecutive twice-daily HBO treatments (n = 9; 100% oxygen for 1 h at 2.5 atmospheres absolute) after transplantation.