Comparison of machine learning algorithms to predict dissolved oxygen in an urban stream.

Water quality monitoring for urban watersheds is critical to identify the negative urbanization impacts. This study sought to identify a successful predictive machine learning model with minimal parameters from easy-to-deploy, low-cost sensors to create a monitoring system for the urban stream network, Hunnicutt Creek, in Clemson, SC, USA. A multiple linear regression model was compared to machine learning algorithms k-nearest neighbor, decision tree, random forest, and gradient boosting. These algorithms were evaluated to understand which best predicted dissolved oxygen (DO) from water temperature, conductivity, turbidity, and water level change at four locations along the urban stream. The random forest algorithm had the highest performance in predicting DO for all four sites, with Nash-Sutcliffe model efficiency coefficient (NSE) scores > 0.9 at three sites and > 0.598 at the fourth site. The random forest model was further examined using explainable artificial intelligence (XAI) and found that temperature influenced the DO predictions for three of the four sites, but there were different water quality interactions depending on site location. Calculating the land cover type in each site's sub-watershed revealed that different amounts of impervious surface and vegetation influenced water quality and the resulting DO predictions. Overall, machine learning combined with land cover data helps decision-makers better understand the nuances of urban watersheds and the relationships between urban land cover and water quality.

Evaluation of a new low-cost particle sensor as an internet-of-things device for outdoor air quality monitoring.

Many low-cost particle sensors are available for routine air quality monitoring of PM2.5, but there are concerns about the accuracy and precision of the reported data, particularly in humid conditions. The objectives of this study are to evaluate the Sensirion SPS30 particulate matter (PM) sensor against regulatory methods for measurement of real-time particulate matter concentrations and to evaluate the effectiveness of the Intelligent AirTM sensor pack for remote deployment and monitoring. To achieve this, we co-located the Intelligent AirTM sensor pack, developed at Clemson University and built around the Sensirion SPS30, to collect data from July 29, 2019, to December 12, 2019, at a regulatory site in Columbia, South Carolina. When compared to the Federal Equivalent Methods, the SPS30 showed an average bias adjusted R2 = 0.75, mean bias error of -1.59, and a root mean square error of 2.10 for 24-hour average trimmed measurements over 93 days, and R2 = 0.57, mean bias error of -1.61, and a root mean square error of 3.029, for 1-hr average trimmed measurements over 2300 hours when the central 99% of data was retained with a data completeness of 75% or greater. The Intelligent AirTM sensor pack is designed to promote long-term deployment and includes a solar panel and battery backup, protection from the elements, and the ability to upload data via a cellular network. Overall, we conclude that the SPS30 PM sensor and the Intelligent AirTM sensor pack have the potential for greatly increasing the spatial density of particulate matter measurements, but more work is needed to understand and calibrate sensor measurements.Implications: This work adds to the growing body of research that indicates that low-cost sensors of particulate matter (PM) for air quality monitoring has a promising future, and yet much work is left to be done. This work shows that the level of data processing and filtering effects how the low-cost sensors compare to existing federal reference and equivalence methods: more data filtering at low PM levels worsens the data comparison, while longer time averaging improves the measurement comparisons. Improvements must be made to how we handle, calibrate, and correct PM data from low-cost sensors before the data can be reliably used for air quality monitoring and attainment.

Diagnostic significance of flow cytometry scales in diagnostics of myelodysplastic syndromes.

BACKGROUND: Myelodysplastic syndromes (MDS) can present a challenge for clinicians. Multicolor flow cytometry (MFC) can aid in establishing a diagnosis. The aim of this study was to determine the optimal MFC approach for MDS. METHODS: The study included 102 MDS (39 low-grade MDS), 83 cytopenic patients without myeloid neoplastic disorders (control group), and 35 healthy donors. Bone marrow was analyzed using a six-color MFC. Analysis was conducted according to the "Ogata score," "Wells score," and the integrated flow cytometry (iFC) score. RESULTS: The respective sensitivity and specificity values were 77.5% and 90.4% for the Ogata score, 79.4% and 81.9% for the Wells score, and 87.3% and 87.6% for the iFC score. Specificity was not 100% due to deviations of MFC parameters in the control group. Patients with paroxysmal nocturnal hemoglobinuria (PNH) had higher levels of CD34+ CD7+ myeloid cells than donors. Aplastic anemia and PNH were characterized by a high proportion of CD56+ cells among CD34+ precursors and neutrophils. The proportion of MDS-related features increased with the progression of MDS. The highest number of CD34+ blasts was found in MDS with excess blasts. MDS with isolated del(5q) was characterized by a high proportion of CD34+ CD7+ cells and low granularity of neutrophils. In 39 low-grade MDS, the sensitivities were 53.8%, 61.5%, and 71.8% for Ogata score, Wells score, and iFC, respectively. CONCLUSION: The results support iFC as a useful diagnostic tool in MDS.

Evaluating the integrity of forested riparian buffers over a large area using LiDAR data and Google Earth Engine.

Spatial and temporal changes in land cover have direct impacts on the hydrological cycle and stream quality. Techniques for accurately and efficiently mapping these changes are evolving quickly, and it is important to evaluate how useful these techniques are to address the environmental impact of land cover on riparian buffer areas. The objectives of this study were to: (1) determine the classes and distribution of land cover in the riparian areas of streams; (2) examine the discrepancies within the existing land cover data from National Land Cover Database (NLCD) using high-resolution imagery of the National Agriculture Imagery Program (NAIP) and a LiDAR canopy height model; and (3) develop a technique using LiDAR data to help characterize riparian buffers over large spatial extents. One-meter canopy height models were constructed in a high-throughput computing environment. The machine learning algorithm Support Vector Machine (SVM) was trained to perform supervised land cover classification at a 1-m resolution on the Google Earth Engine (GEE) platform using NAIP imagery and LiDAR-derived canopy height models. This integrated approach to land cover classification provided a substantial improvement in the resolution and accuracy of classifications with F1 Score of each land cover classification ranging from 64.88 to 95.32%. The resulting 1-m land cover map is a highly detailed representation of land cover in the study area. Forests (evergreen and deciduous) and wetlands are by far the dominant land cover classes in riparian zones of the Lower Savannah River Basin, followed by cultivated crops and pasture/hay. Stress from urbanization in the riparian zones appears to be localized. This study demonstrates a method to create accurate high-resolution riparian buffer maps which can be used to improve water management and provide future prospects for improving buffer zones monitoring to assess stream health.

Modeling and monitoring riparian buffer zones using LiDAR data in South Carolina.

Functional riparian areas protect water quality and conserve aquatic systems, plants, and wildlife. Laser-based remote sensing technology offers a high-resolution approach to both characterize and document changes in riparian buffer zones (RBZs). The objectives of this study were to demonstrate a rapid method and model to calculate riparian buffer widths on both sides of a stream using a LiDAR-derived slope variable, to classify riparian buffers and determine their quality, and to evaluate the appropriateness of using LiDAR in riparian buffer assessment. For this purpose, RBZs were delineated for Hunnicutt and King Creek, which are located in Oconee and Pickens counties, in South Carolina. Results show that LiDAR was effective in delineating required riparian buffer widths based on the topography slope of upstream areas, and in calculating the ratio of tree cover. This LiDAR-based assessment methodology could be applied to a wide-range of environments.

Monitoring spatial and temporal variation of dissolved oxygen and water temperature in the Savannah River using a sensor network.

Dissolved oxygen is a critical component of river water quality. This study investigated average weekly dissolved oxygen (AWDO) and average weekly water temperature (AWT) in the Savannah River during 2015 and 2016 using data from the Intelligent River® sensor network. Weekly data and seasonal summary statistics revealed distinct seasonal patterns that impact both AWDO and AWT regardless of location along the river. Within seasons, spatial patterns of AWDO and AWT along the river are also evident. Linear mixed effects models indicate that AWT and low and high river flow conditions had a significant impact on AWDO, but added little predictive information to the models. Low and high river flow conditions had a significant impact on AWT, but also added little predictive information to the models. Spatial linear mixed effects models yielded parameter estimates that were effectively the same as non-spatial linear mixed effects models. However, components of variance from spatial linear mixed effects models indicate that 23-32% of the total variance in AWDO and that 12-18% of total variance in AWT can be apportioned to the effect of spatial covariance. These results indicate that location, week, and flow-directional spatial relationships are critically important considerations for investigating relationships between space- and time-varying water quality metrics.

Design and evaluation of a bioreactor with application to forensic burial environments.

Existing forensic taphonomic methods lack specificity in estimating the postmortem interval (PMI) in the period following active decomposition. New methods, such as the use of citrate concentration in bone, are currently being considered; however, determining the applicability of these methods in differing environmental contexts is challenging. This research aims to design a forensic bioreactor that can account for environmental factors known to impact decomposition, specifically temperature, moisture, physical damage from animals, burial depth, soil pH, and organic matter content. These forensically relevant environmental variables were characterized in a soil science context. The resulting metrics were soil temperature regime, soil moisture regime, slope, texture, soil horizon, cation exchange capacity, soil pH, and organic matter content. Bioreactor chambers were constructed using sterilized thin-walled polystyrene boxes housed in calibrated temperature units. Gravesoil was represented using mineral soil (Ultisols), and organic soil proxy for Histosols, horticulture mix. Gravesoil depth was determined using mineral soil horizons A and Bt2 to simulate surface scatter and shallow grave burial respectively. A total of fourteen different environmental conditions were created and controlled successfully over a 90-day experiment. These results demonstrate successful implementation and control of forensic bioreactor simulating precise environments in a single research location, rather than site-specific testing occurring in different geographic regions. Bone sections were grossly assessed for weathering characteristics, which revealed notable differences related to exposure to different temperature regimes and soil types. Over the short 90-day duration of this experiment, changes in weathering characteristics were more evident across the different temperature regimes rather than the soil types. Using this methodology, bioreactor systems can be created to replicate many different clandestine burial contexts, which will allow for the more rapid understanding of environmental effects on skeletal remains.

An integrated WebGIS framework for volunteered geographic information and social media in soil and water conservation.

Volunteered geographic information and social networking in a WebGIS has the potential to increase public participation in soil and water conservation, promote environmental awareness and change, and provide timely data that may be otherwise unavailable to policymakers in soil and water conservation management. The objectives of this study were: (1) to develop a framework for combining current technologies, computing advances, data sources, and social media; and (2) develop and test an online web mapping interface. The mapping interface integrates Microsoft Silverlight, Bing Maps, ArcGIS Server, Google Picasa Web Albums Data API, RSS, Google Analytics, and Facebook to create a rich user experience. The website allows the public to upload photos and attributes of their own subdivisions or sites they have identified and explore other submissions. The website was made available to the public in early February 2011 at http://www.AbandonedDevelopments.com and evaluated for its potential long-term success in a pilot study.

Alterations in hematopoietic microenvironment in patients with aplastic anemia.

Mechanisms of hematopoietic failure in patients with aplastic anemia (AA) are obscure. We investigate alterations in the hematopoietic microenvironment in AA patients. We present the results of studying mesenchymal stromal cells (MSC), fibroblastic colony-forming units (CFU-F), and adherent cell layers (ACL) of long-term bone marrow cultures (LTBMC) from bone marrow (BM) samples of AA patients. MSC of AA patients proliferated longer than those of donors. In half of the patients' MSC cultures, adipogenesis was impaired. Osteogenic differentiation was not achieved in 36% of AA MSC. CFU-F formed enlarged colonies, and their concentration in the BM of AA patients was significantly increased. Our data suggest that the physiological activation of the stromal microenvironment is characteristic of AA. We detected a decrease in the expression of the angiopoetin-1 (ANG-1) and vascular cell adhesion molecule-1 (VCAM-1) genes, together with an increase in the expression of vascular endothelial growth factor (VEGF) in ACL of AA patients. This indicates abnormal regulatory patterns in both osteoblastic and vascular contexts. Addition of AA patients' serum to donors' LTBMC for 3 weeks induced similar gene expression alterations. The addition of parathyroid hormone (PTH) resulted in the expression levels of analyzed genes returning to normal, in both AA LTBMC and donor cultures treated with AA serum. The physiologic status of the BM stromal microenvironment (MSC, CFU-F, and ACL of LTBMC) of AA patients was altered.

Effects of land use on soil inorganic carbon stocks in the Russian Chernozem.

Little is known about changes in soil inorganic carbon (SIC) stocks with depth and with land use in grassland ecosystems. This study was conducted to determine SIC stocks under different management regimes in the Mollisol, one of the typical soils in grasslands. Four sites were sampled: a native grassland field (not cultivated for at least 300 yr), an adjacent 50-yr continuous fallow field, a yearly cut hay field in the V.V. Alekhin Central-Chernozem Biosphere State Reserve in the Kursk region of Russia, and a continuously cropped field in the Experimental Station of the Kursk Institute of Agronomy and Soil Erosion Control. All sampled soils were classified as fine-silty, mixed, frigid Pachic Hapludolls. Significant differences occurred in SIC stocks between cultivated and grassland soil. The inorganic carbon stocks in the top 2 m were 107 Mg ha(-1) for the native grassland, 91 Mg ha(-1) for the yearly cut hay field, 242 Mg ha(-1) for the continuously cropped field, and 196 Mg ha(-1) for the 50-yr continuous fallow. The SIC was in the form of calcium carbonate and was mostly stored below the 1-m depth. The largest difference between inorganic carbon stocks was observed between the continuously cropped field and native grassland. The increase in inorganic carbon in the continuously cropped field and continuous fallow was attributed to initial cultivation and fertilization. Soil inorganic carbon in Mollisols is not accounted for in the current global carbon estimates.