Adjusting NRCS Curve Number for Rainfall Durations Less Than 24 Hours

2014 S.C. Water Resources Conference - Informing Strategic Water Planning to Address Natural Resource, Community and Economic Challenge

Mathematical Model for Water Quality in Streams Impacted by Point and Nonpoint Source Pollution

Modeling the impacts of stormwater runoff on small streams, requires that the prediction model has the capability of simulating the behavior of the hydrologic and water quality components of the stream system. Development of such a model involves coupling the equations for pollutant transport during unsteady flow with the appropriate flood routing equations. The decision on which equations to choose requires a full understanding of the pollutant transport and hydrograph dispersion processes. This research was undertaken to develop a rigorous theoretical evaluation of the pollutant transport and hydrograph dispersion processes during unsteady flow, and to recommend a suitable model for simulating the impact of stormwater on small streams. It was determined that the one dimensional convective - dispersive equation for tracers (pollutants) coupled with a form of the diffusive wave model for unsteady streamflow would provide the basis for a simulation model that is both simple and consistent with the principal transport processes. Evaluation of the dynamic terms in the momentum equation yielded general estimators to model parameters and established that the Muskingum routing model is consistent with the modified diffusive wave model developed during this research. The coefficient for hydrograph dispersion was tested on tracer dispersion data and was found to be a reasonable prediction equation for channels with top widths less than 115 feet and bed slopes greater than 1.6 feet per mile. Most small streams satisfy these conditions

Improved Methods and Guidelines for Modeling Stormwater Runoff from Surface Coal Mined Lands

The investgations, developments and guidelines for several hydrologic modeling strategies are presented. Investigations were conducted to determine appropriate event curve numbers for surface mined disturbed watersheds; and performance of four synthetic unit hydrograph models (SCS curvilinear, SCS single triangle, Williams and TVA double triangle) on 38 USDA experimental watersheds in 14 physiographic provinces using in excess of 270 events. A second test using only the SCS curvilinear unit hydrograph on 11 small watersheds and 48 events was conducted to investigate the excess rainfall pattern simulated with the curve number model. A procedure for developing a unit hydrograph using the time area method and a two parameter gamma distribution is presented for ungaged watersheds or watersheds undergoing land use changes. The development of a coupled explicit finite difference Green and Ampt infiltration-implicit finite element kinematic wave model is presented. The deterministic overland flow model includes a variable width which is essential for the accurate modeling of the watershed geometry. Both impervious and pervious watershed simulations are presented for the deterministic overland flow model

Examining the Robustness of the SWAT Distributed Model Using PSO and GLUE Uncertainty Frameworks

2014 S.C. Water Resources Conference - Informing Strategic Water Planning to Address Natural Resource, Community and Economic Challenge

Critical Assessment of Management Practices and Policies for Stormwater and Sediment Ponds in South Carolina

2010 S.C. Water Resources Conference - Science and Policy Challenges for a Sustainable Futur

What are effective therapies for Clostridium difficile- associated diarrhea?

Oral metronidazole and oral vancomycin are equally effective treatments for Clostridium difficile- associated diarrhea (CDAD) (strength of recommendation [SOR]: A, based on randomized trials). Oral vancomycin is considerably more expensive and may select for colonization with vancomycin-resistant enterococci, leading the American College of Gastroenterology to recommend oral metronidazole as preferred therapy (SOR: C, expert opinion). They recommend therapy with vancomycin for those who are pregnant, breast feeding, less than 10years old, nonresponders to metronidazole, critically ill, or allergic or intolerant to metronidazole (SOR: C, expert opinion)

Should home apnea monitoring be recommended to prevent SIDS?

While home apnea monitoring may find an increased incidence of apnea and bradycardia in preterm infants compared with term infants, no association links these events with sudden infant death syndrome (SIDS). Apnea of prematurity is not a proven risk factor for SIDS. Since apnea of prematurity has not been shown to be a precursor to SIDS, home apnea monitoring for the purpose of preventing SIDS cannot be recommended (strength of recommendation [SOR]: B, based on a single prospective cohort study and multiple case-control studies). Neonates with significant neurologic or pulmonary disease may benefit from apnea monitoring (SOR: C, expert opinion)

How Does the Geography Curriculum Contribute to Education for Sustainable Development? Lessons from China and the USA

Education for Sustainable Development (ESD) must play an important part in achieving the Sustainable Development Goals and, while it may be advanced through harnessing the unique advantages of the geography curriculum, connections between the geography curriculum and sustainable development competencies have not yet been systematically investigated in China and America. In order to explore the value of geography education in promoting learner competencies in sustainable development, we conducted a detailed analysis of China’s geography curriculum standards and American geography curriculum standards, and explored the potential contribution of the geography curriculum to ESD. Learning objectives in China’s geography curriculum standards for middle school (98 items) and high school (141 items), and American geography curriculum standards for middle school (80 items) and high school (85 items) were analyzed using content analysis supported by WordStat 8.0. Our findings suggest that geography education plays an important role in cultivating learners’ cognition and ability regarding sustainable development, although there remains much room for improvement in cultivating learner attitudes and values towards ESD

Double-difference waveform inversion: Feasibility and robustness study with pressure data

Time-lapse seismic data are widely used to monitor reservoir changes. Qualitative comparisons between baseline and monitor data sets or image volumes provide information about fluid and pressure effects within the reservoir during production. However, to perform real quantitative analysis of such reservoir changes, quantitative estimates of the elastic parameters are required as input parameters to rock-physics-based reservoir models. Full-waveform inversion has been proposed as a potential tool for retrieving subsurface properties, such as P- and S-wave velocities and density by fitting simulated waveforms to seismic data. An extension of this method to time-lapse applications seems straightforward, but, in fact, it requires more tailored processes such as double-difference waveform inversion (DDWI). We used realistic 2D synthetic pressure data examples to compare the performance of DDWI with that of two other inversion schemes: one using the same starting model for both inversions and the other starting the monitor inversion with the final baseline inversion model. The data simulation and inversion were based on acoustic theory. Although P-wave velocity changes were reliably recovered by each inversion method, DDWI was found to deliver the best results when perfectly repeated surveys were used. However, differencing the baseline and monitor data sets, as required by DDWI, could be found to be sensitive to the presence of survey nonrepeatability. To investigate the feasibility of using DDWI in practice, the dependence of DDWI on the quality of the baseline models and its robustness to survey nonrepeatability were studied with numerical tests. Various types of nonrepeatability were considered separately in the synthetic tests, including random noise, acquisition geometry mismatch, source wavelet discrepancy, and overburden velocity changes. A study of the correlation between the levels and types of nonrepeatability and the resulting contamination of the inversion results found that, for pressure data, DDWI was capable of inverting reliably for P-wave velocity changes under realistic survey nonrepeatability conditions

Coalignment of plasma membrane channels and protrusions (fibripositors) specifies the parallelism of tendon

The functional properties of tendon require an extracellular matrix (ECM) rich in elongated collagen fibrils in parallel register. We sought to understand how embryonic fibroblasts elaborate this exquisite arrangement of fibrils. We show that procollagen processing and collagen fibrillogenesis are initiated in Golgi to plasma membrane carriers (GPCs). These carriers and their cargo of 28-nm-diam fibrils are targeted to previously unidentified plasma membrane (PM) protrusions (here designated “fibripositors”) that are parallel to the tendon axis and project into parallel channels between cells. The base of the fibripositor lumen (buried several microns within the cell) is a nucleation site of collagen fibrillogenesis. The tip of the fibripositor is the site of fibril deposition to the ECM. Fibripositors are absent at postnatal stages when fibrils increase in diameter by accretion of extracellular collagen, thereby maintaining parallelism of the tendon. Thus, we show that the parallelism of tendon is determined by the late secretory pathway and interaction of adjacent PMs to form extracellular channels