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Lake trophic state is a key ecosystem property that integrates a lake's physical, chemical, and biological processes. Despite the importance of trophic state as a gauge of lake water quality, standardized and machine-readable observations are uncommon. Remote sensing presents an opportunity to detect and analyze lake trophic state with reproducible, robust methods across time and space. We used Landsat surface reflectance data to create the first compendium of annual lake trophic state for 55,662 lakes of at least 10 ha in area throughout the contiguous United States from 1984 through 2020. The dataset was constructed with FAIR data principles (Findable, Accessible, Interoperable, and Reproducible) in mind, where data are publicly available, relational keys from parent datasets are retained, and all data wrangling and modeling routines are scripted for future reuse. Together, this resource offers critical data to address basic and applied research questions about lake water quality at a suite of spatial and temporal scales. [ABSTRACT FROM AUTHOR]

The last five years have been one of the most exciting times for the energy storage industry. We have seen significant advancements in the regulatory process to make accommodations for valuing and monetizing energy storage for what it provides to the grid. The most impactful regulatory decision for the energy storage industry has come from California, where the California Public Utilities Commission issued a decision that mandates procurement requirements of 1.325 GW for energy storage to three investor-owned utilities in four stages in 2014, 2016, 2018, and 2020. Furthermore, at the federal level, the U.S. Federal Energy Regulatory Commission's (FERC's) Order 755 requires transmission operators to develop pay-for-performance tariffs for ancillary services. This has had a direct impact on the market design of U.S. competitive wholesale markets and the monetization of fast-responding grid assets. While this order is technology neutral, it clearly plays into the fast-responding capability of energy storage technologies. Today, PJM, CAISO, MISO, NYISO, and NE–ISO have implemented Order 755 and offer new tariff-for-regulation services based on pay-for-performance principles. Furthermore, FERC Order 784, which was issued in July 2013, requires transmission providers to consider speed and accuracy in determining the requirements for ancillary services. In November 2013, FERC issued Order 972, which revises the small generator interconnection agreement that declares energy storage as a power source. This order puts energy storage on par with existing generators. This paper will discuss the implementation of FERC's pay-for-performance regulation order at all independent service operators (ISOs) in the United States under FERC regulatory authority (this excludes ERCOT). Also discussed will be the market impacts and overall impacts on the NERC regulation performance indexes. The paper ends with a discussion on the California, New York, and Ontario, Canada, procurement mandates and the opportunity that it may present to the energy storage industry. [ABSTRACT FROM PUBLISHER]

More than 20% of the bridges in the United States were built more than 50 years ago, at a time in which intense precipitation events were much less common. However, very little work has been done on the use of scour risk-assessment models to assess how climate change increases bridge failure probabilities. This paper develops a risk-assessment framework based on HYRISK, a model developed to assess the probability of a bridge failure due to scour, and illustrates one way in which current engineering risk-assessment models can be used to quantify the additional risks and expected economic losses associated with a changing climate. Application of this framework to all bridges in the United States that carry vehicular traffic over water finds that economic losses due to climate change factors will increase by at least 15% over current losses and that the expected number of annual bridge failures in the United States will increase by at least 10% over current failures. Climate-based risk measures, such as those developed as part of this study, could be included in asset management systems to help state DOTs prioritize maintenance, operation, and replacement schedules. [ABSTRACT FROM AUTHOR]

The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) began experimentation with cryogenic propellants in the early 1950s to understand the potential of these high-performance propellants for use in liquid propellant rocket engines. Supporting these tests required learning how to both design cryogenic systems and develop procedures to safely and reliably work with cryogenic fuels and oxidizers. This early work led to the development of a skill set that has been core to the center ever since. When NASA was formed and the exploration missions were defined, it became clear that the ability to use cryogenic propellants in the thermal and microgravity environment of space was critical to mission success, and the agency was tasked with enabling this capability. To support development of the Centaur upper stage and the Saturn S-IVB stage, GRC researchers and engineers initiated extensive technology development for the in-space application of cryogenic fluid management (CFM). These initial efforts addressed basic requirements of propellant slosh, settling, and short-term storage/pressure control. Over the ensuing years, the NASA GRC has advanced CFM technologies to enable more reliable and capable upper stages. Today, these CFM technologies are on the brink of enabling long-duration in-space cryogenic propulsion stages and cryogenic propellant depots. [ABSTRACT FROM AUTHOR]

Abstract: During the summer of 2010, NASA''s Office of Chief Technologist assembled 15 civil service teams to support the creation of a NASA integrated technology roadmap. The Aero-Space Technology Area Roadmap is an integrated set of technology area roadmaps recommending the overall technology investment strategy and prioritization for NASA''s technology programs. The integrated set of roadmaps will provide technology paths needed to meet NASA''s strategic goals. The roadmaps have been reviewed by senior NASA management and the National Research Council. With the exception of electric propulsion systems used for commercial communications satellite station-keeping and a handful of deep space science missions, almost all of the rocket engines in use today are chemical rockets; that is, they obtain the energy needed to generate thrust by combining reactive chemicals to create a hot gas that is expanded to produce thrust. A significant limitation of chemical propulsion is that it has a relatively low specific impulse. Numerous concepts for advanced propulsion technologies with significantly higher values of specific impulse have been developed over the past 50 years. Advanced in-space propulsion technologies will enable much more effective exploration of our solar system, near and far, and will permit mission designers to plan missions to “fly anytime, anywhere, and complete a host of science objectives at the destinations” with greater reliability and safety. With a wide range of possible missions and candidate propulsion technologies with very diverse characteristics, the question of which technologies are ‘best’ for future missions is a difficult one. A portfolio of technologies to allow optimum propulsion solutions for a diverse set of missions and destinations are described in the roadmap and herein. [Copyright &y& Elsevier]

Fungicides are used to prevent foliar diseases on a wide range of vegetable, field, fruit, and ornamental crops. They are generally more effective as protective rather than curative treatments, and hence tend to be applied before infections take place. Less than 1% of US soybeans were treated with a fungicide in 2002 but by 2006, 4% were treated. Like other pesticides, fungicides can move-off of fields after application and subsequently contaminate surface water, groundwater, and associated sediments. Due to the constant pressure from fungal diseases such as the recent Asian soybean rust outbreak, and the always-present desire to increase crop yields, there is the potential for a significant increase in the amount of fungicides used on US farms. Increased fungicide use could lead to increased environmental concentrations of these compounds. This study documents the occurrence of fungicides in select US streams soon after the first documentation of soybean rust in the US and prior to the corresponding increase in fungicide use to treat this problem. Water samples were collected from 29 streams in 13 states in 2005 and/or 2006, and analyzed for 12 target fungicides. Nine of the 12 fungicides were detected in at least one stream sample and at least one fungicide was detected in 20 of 29 streams. At least one fungicide was detected in 56% of the 103 samples, as many as five fungicides were detected in an individual sample, and mixtures of fungicides were common. Azoxystrobin was detected most frequently (45% of 103 samples) followed by metalaxyl (27%), propiconazole (17%), myclobutanil (9%), and tebuconazole (6%). Fungicide detections ranged from 0.002 to 1.15 μg/L. There was indication of a seasonal pattern to fungicide occurrence, with detections more common and concentrations higher in late summer and early fall than in spring. At a few sites, fungicides were detected in all samples collected suggesting the potential for season-long occurrence in some streams. Fungicide occurrence appears to be related to fungicide use in the associated drainage basins; however, current use information is generally lacking and more detailed occurrence data are needed to accurately quantify such a relation. Maximum concentrations of fungicides were typically one or more orders of magnitude less than current toxicity estimates for freshwater aquatic organisms or humans; however, gaps in current toxicological understandings of the effects of fungicides in the environment limit these interpretations. [ABSTRACT FROM AUTHOR]

The prevalence of organic wastewater compounds in surface waters of the United States has been reported in a number of recent studies. In karstic areas, surface contaminants might be transported to groundwater and, ultimately, cave ecosystems, where they might impact resident biota. In this study, polar organic chemical integrative samplers (POCISs) and semipermeable membrane devices (SPMDs) were deployed in six caves and two surface-water sites located within the Ozark Plateau of northeastern Oklahoma and northwestern Arkansas in order to detect potential chemical contaminants in these systems. All caves sampled were known to contain populations of the threatened Ozark cavefish ( Amblyopsis rosae). The surface-water site in Oklahoma was downstream from the outfall of a municipal wastewater treatment plant and a previous study indicated a hydrologic link between this stream and one of the caves. A total of 83 chemicals were detected in the POCIS and SPMD extracts from the surface-water and cave sites. Of these, 55 chemicals were detected in the caves. Regardless of the sampler used, more compounds were detected in the Oklahoma surface-water site than in the Arkansas site or the caves. The organic wastewater chemicals with the greatest mass measured in the sampler extracts included sterols (cholesterol and β-sitosterol), plasticizers [diethylhexylphthalate and tris(2-butoxyethyl) phosphate], the herbicide bromacil, and the fragrance indole. Sampler extracts from most of the cave sites did not contain many wastewater contaminants, although extracts from samplers in the Oklahoma surface-water site and the cave hydrologically linked to it had similar levels of diethylhexyphthalate and common detections of carbamazapine, sulfamethoxazole, benzophenone, N-diethyl-3-methylbenzamide (DEET), and octophenol monoethoxylate. Further evaluation of this system is warranted due to potential ongoing transport of wastewater-associated chemicals into the cave. Halogenated organics found in caves and surface-water sites included brominated flame retardants, organochlorine pesticides (chlordane and nonachlor), and polychlorinated biphenyls. The placement of samplers in the caves (near the cave mouth compared to farther in the system) might have influenced the number of halogenated organics detected due to possible aerial transport of residues. Guano from cave-dwelling bats also might have been a source of some of these chlorinated organics. Seven-day survival and growth bioassays with fathead minnows ( Pimephales promelas) exposed to samples of cave water indicated initial toxicity in water from two of the caves, but these effects were transient, with no toxicity observed in follow-up tests. [ABSTRACT FROM AUTHOR]

We used recent developments in theoretical population ecology to construct basic models of common loon (Gavia immer) demography and population dynamics. We parameterized these models using existing survival estimates and data from long-term monitoring of loon productivity and abundance. Our models include deterministic, 2-stage, density-independent matrix models, yielding population growthrate estimates (λ) of 0.99 and 1.01 for intensively studied populations in our Wisconsin, USA, and New Hampshire, USA, study areas, respectively. Perturbation analysis of these models indicated that estimated growth rate is extremely sensitive to adult survival, as expected for this long-lived species. Also, we examined 20 years of count data for the 2 areas and evaluated support for a set of count-based models of population growth. We detected no temporal trend in Wisconsin, which would be consistent with fluctuation around an average equilibrium state but could also result from data limitations. For New Hampshire, the model set included varying formulations of density dependence and partitioning of stochasticity that were enabled by the annual sampling resolution. The best model for New Hampshire included density regulation of population growth and, along with the demographic analyses for both areas, provided insight into the possible importance of breeding habitat availability and the abundance of nonbreeding adults. Based on these results, we recommend that conservation organizations include nonbreeder abundance in common loon monitoring efforts and that additional emphasis be placed on identifying and managing human influences on adult loon survival. [ABSTRACT FROM AUTHOR]

The article offers information about the critical care air transport program of the U.S. Air Force Aeromedical Evacuation System. It is stated that the critical care air transport team has been successful in disaster response, and in supporting casualties in combat. The article explores more of the contribution of this program.

In recent years, there has been a dramatic increase in studies exploring associations between the built environment and obesity. Many studies have found that built environment characteristics, such as high-density land developments, mixed-land uses, and connected street networks, are associated with lower rates of obesity. However, depending on the research field and the researcher, how one specifies the experimental model and how sociodemographic characteristics of the population are defined and included in the model has led to different policy conclusions and implications. This is not a surprising observation; however, it is one that does seem to have been lost in current discussions. This article highlights several data-processing, model-specification, and model-estimation factors that should be comprehensively considered in studies of the built environment and obesity. Empirical results based on data from Atlanta, GA, USA, illustrate that the association between the built environment and obesity is sensitive to how age, income, and educational attainment are included in the model. Also, a detailed examination of land-use-mix measures shows that it is difficult to create this measure and that results are sensitive to the treatment of missing values. Models that distinguish between overweight and obese individuals are shown to provide richer insights into the associations among obesity, built environment, and sociodemographic characteristics for the Atlanta area. The article concludes by offering modeling recommendations for future studies. [ABSTRACT FROM AUTHOR]

Isoxaflutole (IXF), a newer low application rate herbicide, was introduced for weed control in corn (Zea mays) to use as an alternative to widely applied herbicides such as atrazine. The transport of LXF in streamwater has not been well-studied. The fate and transport of IXF and two of its degradation products was studied in 10 Iowa rivers during 2004. IXF rapidly degrades to the herbicidally active diketonitrile (DKN), which degrades to a biologically inactive benzoic acid (BA) analogue. IXF was detected in only four, DKN in 56, and BA in 43 of 75 samples. The concentrations of DKN and BA were approximately 2 orders of magnitude less than those of the commonly detected triazine and acetamide herbicides and their degradation products. Concentrations of IXF, DKN, and BA were highest during the May through June postplanting period. The concentration ratio of BNOKN was similar to the deethylatrazine/atrazine ratio with smaller ratios occurring during May and June. The relative temporal variation of DKN and BA was similar to that observed for atrazine and deethylatrazine. This study shows that low application rate herbicides can have similar temporal transport patterns in streamwater as compared to more widely applied herbicides but at lower concentrations. [ABSTRACT FROM AUTHOR]

Currently, little is known about the role of nurses' aides (NAs) in rural long-term care facilities or their impact on the process of death and dying in rural healthcare environments. Focus groups with NAs were held in 6 rural counties located in 5 states to assess attitudes and perceptions about end-of-life care and training needs. Key informants from 8 states and the District of Columbia added to the understandings. Nurses' aides (N= 63) and key informants (N = 21) worked in a variety of rural settings that provide end-of-life care (i.e., nursing homes, hospitals, hospices, home healthcare agencies). Five themes about the needs of rural NAs around end-of-life care were identified in the focus groups, and 4 themes emerged from key informant interviews. A prototype computer-based training module on communication about end-of-life issues was developed, tested, and found useful and compelling. [ABSTRACT FROM AUTHOR]

The article focuses on the study of the occurrence of pharmaceuticals and organic chemicals in water resources in selected north-central and northwestern Arkansas streams in the United States. The purpose of study is to evaluate the existence pharmaceuticals, antibiotics, and organic chemicals in seven selected streams in the state. Water samples with the influence of discharges are collected in northwestern Arkansas. Antibiotic, pharmaceutical, and other organic chemicals are detected at all sites except at Spavinaw Creek located near Mayesville, Arkansas.

This study utilized telemetric systems to sample microbes and pathogens in forest, burned forest, rangeland, and urban watersheds to assess surface water quality in northern New Mexico. Four sites included remote mountainous watersheds, prairie rangelands, and a small urban area. The telemetric system was linked to dataloggers with automated event monitoring equipment to monitor discharge, turbidity, electrical conductivity, water temperature, and rainfall during base flow and storm events. Site data stored in dataloggers was uploaded to one of three types of telemetry: 1) radio in rangeland and urban settings; 2) a conventional phone/modem system with a modem positioned at the urban/forest interface; and 3) a satellite system used in a remote mountainous burned forest watershed. The major variables affecting selection of each system were site access, distance, technology, and cost. The systems were compared based on operation and cost. Utilization of telecommunications systems in this varied geographic area facilitated the gathering of hydrologic and water quality data on a timely basis. [ABSTRACT FROM AUTHOR]

Several state Departments of Transportation (DOTs) and metropolitan planning organizations (MPOs) in the United States are considering environmental issues in the early stages of the transportation planning process, recognizing that there are benefits to be gained from better decisions, reduced public controversy, and shortened times to project implementation. This paper examines the current practice of such consideration, with special emphasis on best case examples. The study was conducted through a literature review, a survey of state DOTs and MPOs, and the identification of best case examples. The findings indicate the emergence, both in the literature and in practice, of more formal recognition of the need to consider environmental factors earlier in the planning process. State DOTs and MPOs agree that air quality, land use, socio-economic, environmental justice, and community cohesion impacts are of greatest concern today, and will be so in 10 years. Different approaches for considering environmental factors in planning include scenario analysis, environmental analysis of plans, environmental performance measures, consideration of equity issues, new data and analysis tools, and innovative institutional partnerships. [ABSTRACT FROM AUTHOR]

Focuses on a long term field study that was initiated by the Wisconsin Department of Natural Resources in 1992 to elucidate patterns of common loon mercury (Hg) exposure. Results from the analysis of loon blood and feather samples collected from recaptured adult loons in Wisconsin 1992?2000 found evidence of a decline in overall body burdens of mercury in common loons for this region; Evidence found showing that a recent regional annual decrease in common loon Hg exposure.

Many southern populations of the common loon (Gavia immer) face threats from lead and methylmercury contamination, lake acidification, shoreline development and human recreation. It is now clear that the task of conserving loon populations will depend upon mitigating these varied threats. In a controlled experiment, we examined the efficacy of using floating nest platforms to increase reproductive success of loons and thus help sustain local populations. Platforms were attractive nesting sites both on lakes that had consistently hatched chicks from natural sites and on lakes where chick production had been sporadic. When compared to natural nest sites, platforms increased hatching success by 69% and fledging success by 32%, apparently through reduction in mammalian egg predation. A well-managed effort to introduce nesting platforms might be a viable strategy to help sustain threatened populations. [Copyright &y& Elsevier]

Identifies the risk factors for deep vein thrombosis (DVT) in medical outpatients in the United States. Regular smoking use; Alcohol consumption; Immobile standing position for hours per day; Diabetes; Inflammatory bowel disease.

Presents the results of an undergraduate civil engineering curriculum revision at the Georgia Institute of Technology in Atlanta, Georgia that was approved for implementation in 1999. Process of the curriculum revision; Emphasis of the curriculum; Specific course requirements of the curriculum.

Compares alternatives to municipal service delivery in the United States. Contracting and intergovernmental agreements; Effects of city characteristics on alternative service structures; Issue of fiscal necessity.