Consequences of Reservoir Drainage on Downstream Water Chemistry, Suspended Sediment, and Nutrients, Southwest Missouri

Construction and subsequent draining of reservoirs can have dramatic affects on the release of nutrients and sediments to waterways. This study describes how the temporary draining of a small reservoir for dam repair influences downstream water quality. The Valley Mill Reservoir has a surface area of 6.1 hectares and volume of 150,000 m3 when filled. Water chemistry monitoring and water sampling were performed at six sites during baseflow and ten sites during runoff events for one year. Water samples were analyzed for total nitrogen (TN), total phosphorous (TP), and total suspended sediment (TSS) concentrations. Results indicate that draining of Valley Mill Reservoir caused only minor changes in water chemistry. However, reservoir drainage caused significant erosion of the exposed lake bed as well as the stream channel upstream of the reservoir. Increases in TSS lagged behind drainage but increased dramatically once drainage was complete. Mean TSS increased from 7.5 mg/L upstream of the reservoir to 20.7 mg/L in reservoir outflow during baseflow. During storm events, TSS increased over 100 percent to nearly 100 mg/L in the drained reservoir outflow, with a maximum concentration of 525 mg/L. The increase in TSS resulted in TP increases during baseflow and storm events, since TP is known to attach to sediment. Mean outflowing TP increased by 10 percent to 43 ug/L during baseflow and by 20 percent to 207 ug/L following storm events. Total nitrogen remained below 5 mg/L at all monitoring sites and decreased by 5 to 15 percent after flowing over the exposed lakebed. Therefore, draining of Valley Mill Reservoir may have caused degradation of water quality downstream of reservoir outflow due to large amounts of sediment and phosphorus being released from the drained reservoir

Examining patterns and drivers of variability in playa water status on the High Plains of western Kansas, 2016–2019

Playa wetlands are widely distributed across the High Plains of the central United States, providing a range of ecosystem services, such as groundwater recharge, surface water storage, and wetland habitat. Although playas are essential resources, few studies have examined the variability and controls on playa water storage. The purpose of this project is to determine how playa and watershed morphology, watershed land cover, and precipitation patterns affect timing and duration of water storage in playas. This project focuses on 92 playas distributed throughout a 10-county region in western Kansas. Playa and watershed morphology were calculated in a GIS environment and classified into quartiles based on playa and watershed surface area. Watershed tilled index (i.e., percent cropland versus grassland) was determined using 2016, 2017, 2018, and 2019 Cropland Data Layers available from the National Agricultural Statistics Service and classified as either cropland (more than 75% cropland), grassland (more than 75% grassland), or mixed. Monthly precipitation data for 2016–2019 were compiled from the Oakley 22S High Plains Regional Climate Center weather station. Playa water status for 2016–2019 was classified monthly as either standing water or dry (i.e., no visible standing water) by visually examining four-band satellite imagery with 3.7 m resolution available from Planet Explorer (www.planet.com). Playa water status is influenced by a combination of factors, including playa and watershed morphology, watershed land cover, and precipitation patterns. Larger playas have larger watersheds and standing water more frequently and for longer periods than smaller playas. Playas in cropland watersheds store water more frequently and for longer periods than playas in grassland watersheds, though differences are not statistically significant. Standing water within playas is positively correlated with monthly precipitation and reflects a short-term response to precipitation patterns, regardless of playa size or watershed land cover. The strongest controls on playa water status are playa area, monthly precipitation, and watershed area. Playas are critical resources for the High Plains, providing a range of ecosystem services that are dependent upon the playa’s ability to store water. Playa functions are under continued threat from cropland expansion, climate change, and playa and watershed modifications. To sustain playa functions in Kansas, efforts should focus on conserving larger grassland playas and reducing sediment inputs to playas in cropland watersheds

Silsesquioxane polymer as a potential scaffold for laryngeal reconstruction

Cancer, disease and trauma to the larynx and their treatment can lead to permanent loss of structures critical to voice, breathing and swallowing. Engineered partial or total laryngeal replacements would need to match the ambitious specifications of replicating functionality, outer biocompatibility, and permissiveness for an inner mucosal lining. Here we present porous polyhedral oligomeric silsesquioxane-poly(carbonate urea) urethane (POSS-PCUU) as a potential scaffold for engineering laryngeal tissue. Specifically, we employ a precipitation and porogen leaching technique for manufacturing the polymer. The polymer is chemically consistent across all sample types and produces a foam-like scaffold with two distinct topographies and an internal structure composed of nano- and micro-pores. Whilst the highly porous internal structure of the scaffold contributes to the complex tensile behaviour of the polymer, the surface of the scaffold remains largely non-porous. The low number of pores minimise access for cells, although primary fibroblasts and epithelial cells do attach and proliferate on the polymer surface. Our data show that with a change in manufacturing protocol to produce porous polymer surfaces, POSS-PCUU may be a potential candidate for overcoming some of the limitations associated with laryngeal reconstruction and regeneration

Update on Electricity Customer Choice In Ohio: Competition Continues to Outperform Traditional Monopoly Regulation (Full Report)

The purpose of this study is to provide an update to the research team’s 2016 report “Electricity Customer Choice in Ohio: How Competition Has Outperformed Traditional Monopoly Regulation” using data for 2016 through 2018. Key Findings: 1. Since 2011, Ohio consumers have saved $23.9 billion because of deregulation. 2. Competition has driven down average electricity prices in deregulated Midwestern states (Ohio, Pennsylvania, Illinois), while their regulated peers (Indiana, Michigan, Wisconsin) have seen a steady increase in price of generated electricity. 3. The Study Team anticipates that savings will continue for the near term to be around$3 billion per year. However, these savings may be lost, in whole or in part, if deregulated energy markets continue to be undermined by cross subsidies of uncompetitive Investor Owned Utility (IOU) generation through Electric Distribution Utility (EDU) riders and surcharges, or through legislatively-mandated, above market Power Purchase Agreements (PPAs) and subsidies

Extended Lifetime in Computational Evolution of Isolated Black Holes

Solving the 4-d Einstein equations as evolution in time requires solving equations of two types: the four elliptic initial data (constraint) equations, followed by the six second order evolution equations. Analytically the constraint equations remain solved under the action of the evolution, and one approach is to simply monitor them ({\it unconstrained} evolution). The problem of the 3-d computational simulation of even a single isolated vacuum black hole has proven to be remarkably difficult. Recently, we have become aware of two publications that describe very long term evolution, at least for single isolated black holes. An essential feature in each of these results is {\it constraint subtraction}. Additionally, each of these approaches is based on what we call "modern," hyperbolic formulations of the Einstein equations. It is generally assumed, based on computational experience, that the use of such modern formulations is essential for long-term black hole stability. We report here on comparable lifetime results based on the much simpler ("traditional") $\dot g$ - $\dot K$ formulation. We have also carried out a series of {\it constrained} 3-d evolutions of single isolated black holes. We find that constraint solution can produce substantially stabilized long-term single hole evolutions. However, we have found that for large domains, neither constraint-subtracted nor constrained $\dot g$ - $\dot K$ evolutions carried out in Cartesian coordinates admit arbitrarily long-lived simulations. The failure appears to arise from features at the inner excision boundary; the behavior does generally improve with resolution.Comment: 20 pages, 6 figure

Engineering biofilms for biocatalysis

Biofilm, friend not foe: Single species biofilms can be engineered to form robust biocatalysts with greater catalytic activity and significantly improved catalytic longevity than purified and immobilised enzymes. We report the engineering, structural analysis and biocatalytic capability of a biofilm that can mediate the conversion of serine and haloindoles to halotryptophans

An Economic Analysis of the Appalachian Coal Industry Ecosystem: Summary Report

The decline in the demand for coal has led to significant negative impacts in areas throughout Appalachia. Consider the integrated effects across components of the coal industry ecosystem (CIE). As extraction activity is diminished, there are ripples through the industry supply chain that extends to a wide number of sectors, occupations, and county and multi-county regions of the Appalachian economy. As these suppliers are impacted, jobs are imperiled, and the fiscal health of communities i s weakened. Displaced workers will need to seek alternative employment opportunities that may entail investments in formal education and training, and this takes both time and resources. As the economic base suffers, state and local governments will see their capacity to fund education weaken as well. The decline in natural gas prices and increasing environmental concerns, along with the age of the capital stock, has affected coal-fired power generation in the Appalachian Region. When capacity is replaced by natural gas, the demand for the Region’s coal is further distressed. The shifting structure and spatial location of power generation creates additional impacts on the economic base, tax base, and employment prospects. A vibrant rail transportation infrastructure has developed to support coal-related commerce and this regional asset is now at risk. Retirement of portions of the railroad capital stock may translate into higher transportation costs and diminished opportunities for economic development tied to the movement of bulk commodities, inputs, and final products

Can a combination of the conformal thin-sandwich and puncture methods yield binary black hole solutions in quasi-equilibrium?

We consider combining two important methods for constructing quasi-equilibrium initial data for binary black holes: the conformal thin-sandwich formalism and the puncture method. The former seeks to enforce stationarity in the conformal three-metric and the latter attempts to avoid internal boundaries, like minimal surfaces or apparent horizons. We show that these two methods make partially conflicting requirements on the boundary conditions that determine the time slices. In particular, it does not seem possible to construct slices that are quasi-stationary and avoid physical singularities and simultaneously are connected by an everywhere positive lapse function, a condition which must obtain if internal boundaries are to be avoided. Some relaxation of these conflicting requirements may yield a soluble system, but some of the advantages that were sought in combining these approaches will be lost.Comment: 8 pages, LaTeX2e, 2 postscript figure

Unconventional human T cells accumulate at the site of infection in response to microbial ligands and induce local tissue remodeling

The antimicrobial responsiveness and function of unconventional human T cells are poorly understood, with only limited access to relevant specimens from sites of infection. Peritonitis is a common and serious complication in individuals with end-stage kidney disease receiving peritoneal dialysis. By analyzing local and systemic immune responses in peritoneal dialysis patients presenting with acute bacterial peritonitis and monitoring individuals before and during defined infectious episodes, our data show that Vg9/ Vd2+ gd T cells and mucosal-associated invariant T cells accumulate at the site of infection with organisms producing (E)-4- hydroxy-3-methyl-but-2-enyl pyrophosphate and vitamin B2, respectively. Such unconventional human T cells are major producers of IFN-g and TNF-a in response to these ligands that are shared by many microbial pathogens and affect the cells lining the peritoneal cavity by triggering local inflammation and inducing tissue remodeling with consequences for peritoneal membrane integrity. Our data uncover a crucial role for Vg9/Vd2 T cells and mucosal-associated invariant T cells in bacterial infection and suggest that they represent a useful predictive marker for important clinical outcomes, which may inform future stratification and patient management. These findings are likely to be applicable to other acute infections where local activation of unconventional T cells contributes to the antimicrobial inflammatory response

Standardization of Epidemiological Surveillance of Group A Streptococcal Impetigo

Impetigo is a highly contagious bacterial infection of the superficial layer of skin. Impetigo is caused by group A Streptococcus (Strep A) and Staphylococcus aureus, alone or in combination, with the former predominating in many tropical climates. Strep A impetigo occurs mainly in early childhood, and the burden varies worldwide. It is an acute, self-limited disease, but many children experience frequent recurrences that make it a chronic illness in some endemic settings. We present a standardized surveillance protocol including case definitions for impetigo including both active (purulent, crusted) and resolving (flat, dry) phases and discuss the current tests used to detect Strep A among persons with impetigo. Case classifications that can be applied are detailed, including differentiating between incident (new) and prevalent (existing) cases of Strep A impetigo. The type of surveillance methodology depends on the burden of impetigo in the community. Active surveillance and laboratory confirmation is the preferred method for case detection, particularly in endemic settings. Participant eligibility, surveillance population and additional considerations for surveillance of impetigo, including examination of lesions, use of photographs to document lesions, and staff training requirements (including cultural awareness), are addressed. Finally, the core elements of case report forms for impetigo are presented and guidance for recording the course and severity of impetigo provided