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USGS2004

Mammalian sensitivity to elemental gold (Au?)

There is increasing documentation of allergic contact dermatitis and other effects from gold jewelry, gold dental restorations, and gold implants. These effects were especially pronounced among females wearing body-piercing gold objects. One estimate of the prevalence of gold allergy worldwide is 13%, as judged by patch tests with monovalent organogold salts. Eczema of the head and neck was the most common response of individuals hypersensitive to gold, and sensitivity can last for at least several years. Ingestion of beverages containing flake gold can result in allergic-type reactions similar to those seen in gold-allergic individuals exposed to gold through dermal contact and other routes. Studies with small laboratory mammals and injected doses of colloidal gold showed increased body temperatures, accumulations in reticular cells, and dose enhancement in tumor therapy; gold implants were associated with tissue injuries. It is proposed that Au? toxicity to mammals is associated, in part, with formation of the more reactive Au+ and Au3+ species.

Biological Trace Element Research↗

USGS2021

Economic geology and environmental characteristics of antimony deposits

Antimony is commonly listed as a critical mineral, particularly in the United States and European Union [1]. Its criticality, or supply risk, is derived from a combination of economic vulnerability, disruption potential of supply, and trade exposure [2].Disruption potential relates a country’s ability and willingness to supply a commodity. Commodities for which supply is concentrated in the fewest countries have the greatest potential for supply disruption, trade exposure, and economic vulnerability. In 2018, approximately 61% of the world production of antimony was mined from China, followed by Russia (20%) and Tajikistan (10%) [3] (Fig. 3.1). Several reviews of antimony as a critical mineral have been recently published [4, 5]. The uses of antimony can be divided into three main categories: metal products, non-metal uses, and flame retardants [5]. Most metallic antimony use is inlead-acid batteries. Antimony trioxide (Sb 2 O 3 ) combined with halogenated com-pounds is used as a fire retardant in plastics, fabrics, and other applications. Other non-metallic uses include as a catalyst for plastics, and in the glass industry. Emerging uses include data storage and novel photovoltaic cells. Recycling of batteries represents an important reuse of antimony, but other uses of antimony do not lend themselves to recycling. This chapter describes mineral deposit types that are primary sources of antimony, and environmental effects related to their mining. Antimony can be re-covered as either a primary commodity from some deposits or as a by product commodity from some gold or silver deposits. Environmental risks associated with antimony mining include those related to mining in general, such as the acid-generating potential of solid mine waste, and some issues specific to antimony, as described below.

Book chapter↗

USGS2008

Assessment of propeller and off-road vehicle scarring in seagrass beds and wind-tidal flats of the southwestern Gulf of Mexico

We used aerial photography and GIS to establish a quantitative baseline of propeller and off-road vehicle (ORV) scarring in seagrass and wind-tidal flats of the upper Laguna Madre in the Padre Island National Seashore (Texas, USA). We also examined scar recovery through comparison of recent (2002, 2005) and historical (1967) aerial photographs of the study area. Scarring intensity was calculated using two different methods. In the first, polygons were visually drawn around groups of scars on digital images. Scarring intensity was estimated as light (<5%), moderate (5-20%), or severe (>20%), based on the total coverage of scars within each polygon (taking into account the length, width, and density of scars). We developed a more objective method that employed creation of vector grid cells and buffers that incorporated the localized ecological impact of scars. Results of spatial and temporal analysis revealed that the polygon approach greatly underestimated the magnitude of scarring. For example, in a single photograph, 7% of seagrass area was lightly scarred according to the polygon method; but light scarring increased to 51% according to grid analysis of the same image. Our results also indicated that propeller scars in Halodule wrightii beds appear to recover in less than three years and ORV tracks have persisted in the wind-tidal flats for at least 38 years. Our approach provides resource managers with procedures for a more objective and efficient assessment of physical disturbances to seagrass and wind-tidal flats caused by boats and ORVs. ?? 2008 by Walter de Gruyter.

Botanica Marina↗

USGS2010

Calorimetric investigation of Na-K mixing and polymorphism in the alkali feldspars

Heat of solution measurements of the enthalpies of Na-K mixing, Al-Si ordering, and fusion for crystalline solutions and end-member phases in the system Na(AlSi 3 O 8 )–K(AlSi 3 O 8 ) were obtained with a vacuum-jacketed, isoperibolic calorimeter using 20.1 percent hydrofluoric acid at temperatures ranging from 40 to 60°C. Heat of solution data for artificially prepared microcline (–low-albite) crystalline solutions at 49.7°C are represented by Δ H sol = −149.408 + 5.230 N 2 − 5.928 N 1 N 2 2 − 8.457 N 2 N 1 2 kcal/mole based on 39 measurements of 14 different bulk compositions, where N 1 and N 2 denote the mole fractions of NaAlSi 3 O 8 and KAlSi 3 O 8 respectively. The thermochemical uncertainty of the above least-squares formulation is ± 0.032 kcal/mole. Unit-cell parameters determined by least-squares refinement of diffraction data indicate that the excess volumes of Na-K mixing of these microcline solutions are positive over the entire composition range. Combining the calorimetric and crystallographic data leads to the following expression for the variation of molar enthalpy of mixing with pressure: Δ H ex = (5928 + 0.110 P) N 1 N 2 2 + (8457 + 0.110 P ) N 2 N 1 2 cal/mole. The sign and magnitude of Δ H ex determined by calorimetry agree closely with Δ H ex calculated from a third-order Margules formulation of high-temperature two-phase equilibrium data in the critical region.

Zeitschrift für Kristallographie — Crystalline Mat↗

USGS2002

Spatial forecasting of disease risk and uncertainty

Because maps typically represent the value of a single variable over 2-dimensional space, cartographers must simplify the display of multiscale complexity, temporal dynamics, and underlying uncertainty. A choropleth disease risk map based on data for polygonal regions might depict incidence (cases per 100,000 people) within each polygon for a year but ignore the uncertainty that results from finer-scale variation, generalization, misreporting, small numbers, and future unknowns. In response to such limitations, this paper reports on the bivariate mapping of data "quantity" and "quality" of Lyme disease forecasts for states of the United States. Historical state data for 1990-2000 are used in an autoregressive model to forecast 2001-2010 disease incidence and a probability index of confidence, each of which is then kriged to provide two spatial grids representing continuous values over the nation. A single bivariate map is produced from the combination of the incidence grid (using a blue-to-red hue spectrum), and a probabilistic confidence grid (used to control the saturation of the hue at each grid cell). The resultant maps are easily interpretable, and the approach may be applied to such problems as detecting unusual disease occurences, visualizing past and future incidence, and assembling a consistent regional disease atlas showing patterns of forecasted risks in light of probabilistic confidence.

Cartography and Geographic Information Science↗

USGS2003

Projecting global datasets to achieve equal areas

Scientists routinely accomplish global modeling in the raster domain, but recent research has indicated that the transformation of large areas through map projection equations leads to errors. This research attempts to gauge the extent of map projection and resampling effects on the tabulation of categorical areas by comparing the results of three datasets for seven common projections. The datasets, Global Land Cover, Holdridge Life Zones, and Global Vegetation, were compiled at resolutions of 30 arc-second, 1/2 degree, and 1 degree, respectively. These datasets were projected globally from spherical coordinates to plane representations. Results indicate significant problems in the implementation of global projection transformations in commercial software, as well as differences in areal accuracy across projections. The level of raster resolution directly affects the accuracy of areal tabulations, with higher resolution yielding higher accuracy. If the raster resolution is high enough for individual pixels to approximate points, the areal error tends to zero. The 30-arc-second cells appear to approximate this condition.

Cartography and Geographic Information Science↗

USGS2024

Observing systems, modeling, and forecasting

Predicting harmful algal blooms (HABs) requires integrating physical, chemical, and biological data collected from observing networks and then assimilating these data into models, which are used to generate forecasts. In 2005, the Harmful Algal Research and Response: A National Environmental Science Strategy 2005-2015 (HARRNESS, 2005) made recommendations on how to improve HAB modeling and forecasting over the next decade. Key HARRNESS recommendations related to sensing, networking, and modeling HABs included: ● Support the development and validation of new and improved technologies for remote cell and toxin detection, and for modeling and forecasting, ● Improve coordination of monitoring/ and modeling efforts, both at national and regional levels, ● Improve the use of networking technologies for monitoring and modeling efforts, ● Conduct sustained time series measurements of the biotic, chemical, and physical environments impacted by HABs, ● Develop food web models on the ecosystem fate and effects of toxins, ● Develop and improve species-specific models that link to physical-biological models. Here we review HAB observing, modeling, and forecasting advances and technologies and recommend research and management priorities for the next decade and beyond. Our report encompasses sensing technologies, sensor networking and data management, models and forecasts, and the paths to operationalize forecasts. Continued improvements of deployable sensors are foundational to improving early warning indicators, models, and forecasts, which are only as good as the underlying data. Sensing technology has advanced considerably in the last decade; for example, more capable fluorometric pigment sensors can track changes in bloom biomass in real-time. Additionally, automated imaging/classifying systems to identify and quantify key harmful algal (HA) taxa are being routinely deployed. However, deployable toxin sensors are available for only some HAB toxins and continue to be identified as a critical need by researchers and managers. As more and improved sensors and technologies become available, the data quality associated with each sensor needs to be assessed. Data quality encompasses the reliability, accuracy, and uncertainty associated with sensor-generated data. These data need to be of known quality so that researchers, managers, and end-users can reliably determine if the information is appropriate for their intended applications. Many of the data quality recommendations from HARRNESS (2005) are still relevant and have been reiterated within the management community. Understanding and documenting data quality, and when applicable, standardizing best practices for sensor use, continue to be recommended.

Report↗

USGS1935

The bacterial diseases of fish

Of all the diseases responsible for the losses in the hatchery, those caused by the microscopic one-celled organisms, the bacteria, are the most common and present the most serious problem to the hatcheryman. They are found at practically every trout and salmon hatchery during some period of the year. The symptoms of the diseases they cause are difficult to recognize. This in itself is a hazard because treatment, to be successful, must be applied during the early stages or, in cases where no method of treatment is effective, the infected fish must be destroyed before the disease spreads to other parts of the hatchery. Here we have a group of diseases practically universal in distribution, difficult to recognize, and hard to treat even in those cases where a remedy is known. Every hatcheryman should be well acquainted with them for efficient and intelligent control. There follows a brief summary of the present status of our knowledge of the individual diseases.

Progressive Fish-Culturist↗

USGS1935

The protozoan diseases of hatchery fish

Following the somewhat bleak picture painted in the consideration of the bacterial diseases of hatchery fish in the last number of The Progressive Fish Culturist, it is a relief to turn to another large group of fish diseases caused by small, single-celled parasitic animals known as the protozoa. To the hatcheryman, the protozoan diseases of fish are just as important as the bacterial diseases for they are equally destructive if allowed to run unchecked. The protozoan diseases are just as common as those caused by bacteria, particularly at those hatcheries which depend upon lakes or streams for their water supplies. However, a very cheery point of difference exists between these two groups of diseases—the protozoan diseases are easier to recognize and, for the most part, they are exceedingly easy to eradicate. To the hatcheryman who has struggled day and night for weeks in an attempt to combat an epidemic wherein he is rewarded immediately by the satisfying sight of a complete recovery of his infected fish as the direct result of his labors.

Progressive Fish-Culturist↗

USGS1940

Scyphidia micropteri, a new protozoan parasite of largemouth and smallmouth black bass

A small urn‐shaped peritrichous protozoan, apparently an undescribed species, was found on the gills and bodies of largemouth and smallmouth black bass in ponds at Leetown, West Virginia. A heavy mortality among a lot of fingerling largemouth bass probably resulted from suffocation due to the organisms on the gills. Specimens of the parasite, preserved in formalin, measured about 57 microns in length and 24 microns in maximum width. The base of the animal consists of a circular disc about 6 microns in diameter. No evidence was found that the sucker‐like attachment disc penetrated the epidermal cells of the host causing necrotic tissue. The anterior or upper end of the animal has a ciliary disc and two rows of cilia. The body is without cilia and is annulared. The macronucleus is very large, has the shape of an inverted cone and occupies much of the lower half of the body. The small micronucleus apparently lies in the slightly concave surface of the upper part of the macronucleus, although there is doubt on this point. This new species was named Scyphidia micropteri after Micropterus, the generic name of the smallmouth black bass, one of its hosts. The species recently was found by Dr. H. S. Davis on gills of largemouth black bass collected in Radnor Lake, Tennessee, which indicates a wide geographical distribution of the parasite.