Tailings Dust Emissions

Fugitive dust emissions from the storage and handling of mine tailings presents environmental and safety concerns, which must be addressed to promote the land sustainability and the health and safety of individuals around a tailings storage facility (TSF). The investigated dust control methods were agglomeration, binder slurry injection, and topical spray. The Dust Busters determined that pelletizing was the most practical method of agglomeration. In order to produce durable pellets from the mine tailings, which consist primarily of silica, a binder must be added. A variety of binders were considered including magnesium and calcium chloride, bentonite, barite, cement, vinyl polymers, acrylic polymers, starch, carboxymethyl cellulose, and a commercial lignosulfonate/bitumen blend. Portland cement proved to be the most effective binder in regards to the pellet’s cost, structural integrity, and longevity. However, due to the abrasive nature of the tailings, pelletizing is not cost effective in comparison to other dust suppression techniques. Binder slurry injection incorporates a pugmill mixer to inject a binding agent into the tailings slurry. Addition of a binder allows the slurry mixture to form a rigid crust that prevents fugitive dust once dried on the existing tailings dam. While the injected slurry is effective at minimizing dust emissions, it is not economically feasible due to high capital costs. The most effective, environmentally safe, and economically feasible solution to reduce the dust associated with tailings storage facilities is a topical spray solution consisting of a vinyl copolymer. The vinyl copolymer, at relatively low concentrations, produces a robust yet permeable crust along the surface of the tailings, which is unmatched in comparison to the other binding agents. By applying the binder as topical solution rather than injecting the binder into the slurry, the capital cost for effective dust suppression is reduced by eliminating the additional process equipment required for both pelletizing and binder slurry injection. Treating 400 acres per year with a vinyl copolymer application costs $110,000. Existing equipment and personnel are adequate to change from the current magnesium chloride treatment to a vinyl copolymer treatment. Current yearly treatments using the magnesium chloride cost approximately$240,000-$720,000 assuming 1-3 applications per year across the 400 acre area; thus changing to a vinyl copolymer treatment will save$130,000-$390,000 per year

Parasitic Infection Surveillance in Mississippi Delta Children

Some recent studies suggest ongoing transmission of parasitic diseases in the American South; however, surveys in Mississippi children are lacking. We enrolled 166 children (median age 8 years, range 4–13 years) from the Mississippi Delta region and carried out multi-parallel real-time polymerase chain reaction (PCR) for Necator americanus, Ascaris lumbricoides, and Strongyloides stercoralis on their stool samples. Dried blood spots were obtained for multiplex serology antibody detection. Of 166 children, all reported having flushable toilets, 11% had soil exposure, and 34% had a pet dog or cat. None had prior diagnosis or treatment of parasitic disease. Multi-parallel real-time PCRs were negative on the 89 stool DNA extracts available for testing. Dried blood spot testing of all 166 children determined the seroprevalence of IgG antibodies to Toxocara spp. (3.6%), Cryptosporidium (2.4%), S. stercoralis, Fasciola hepatica, and Giardia duodenalis (all 0%). In conclusion, parasitic infections and exposure were scarce in this population. Larger studies of at-risk populations are needed

Parasitic Disease Surveillance, Mississippi, USA

Surveillance for soil-transmitted helminths, strongyloidiasis, cryptosporidiosis, and giardiasis was conducted in Mississippi, USA. PCR performed on 224 fecal samples for all soil-transmitted helminths and on 370 samples for only Necator americanus and Strongyloides stercoralis identified 1 S. stercoralis infection. Seroprevalences were 8.8% for Toxocara, 27.4% for Cryptosporidium, 5.7% for Giardia, and 0.2% for Strongyloides parasites

Simultaneous observations of giant pulses from the Crab pulsar, with the Murchison Widefield Array and Parkes radio telescope: implications for the giant pulse emission mechanism

We report on observations of giant pulses from the Crab pulsar performed simultaneously with the Parkes radio telescope and the incoherent combination of the Murchison Widefield Array (MWA) antenna tiles. The observations were performed over a duration of approximately one hour at a center frequency of 1382 MHz with 340 MHz bandwidth at Parkes, and at a center frequency of 193 MHz with 15 MHz bandwidth at the MWA. Our analysis has led to the detection of 55 giant pulses at the MWA and 2075 at Parkes above a threshold of 3.5σ and 6.5σ, respectively. We detected 51% of the MWA giant pulses at the Parkes radio telescope, with spectral indices in the range of-3.6 > α > -4.9 (Sv μ ∝ Va). We present a Monte Carlo analysis supporting the conjecture that the giant pulse emission in the Crab is intrinsically broadband, the less than 100% correlation being due to the relative sensitivities of the two instruments and the width of the spectral index distribution. Our observations are consistent with the hypothesis that the spectral index of giant pulses is drawn from normal distribution of standard deviation 0.6, but with a mean that displays an evolution with frequency from −3.00 at 1382 MHz, to −2.85 at 192 MHz

Simultaneous observations of giant pulses from the Crab pulsar, with the Murchison Widefield Array and Parkes radio telescope: implications for the giant pulse emission mechanism

We report on observations of giant pulses from the Crab pulsar performed simultaneously with the Parkes radio telescope and the incoherent combination of the Murchison Widefield Array (MWA) antenna tiles. The observations were performed over a duration of approximately one hour at a center frequency of 1382 MHz with 340 MHz bandwidth at Parkes, and at a center frequency of 193 MHz with 15 MHz bandwidth at the MWA. Our analysis has led to the detection of 55 giant pulses at the MWA and 2075 at Parkes above a threshold of 3.5σ and 6.5σ, respectively. We detected 51% of the MWA giant pulses at the Parkes radio telescope, with spectral indices in the range of-3.6 > α > -4.9 (Sv μ ∝ Va). We present a Monte Carlo analysis supporting the conjecture that the giant pulse emission in the Crab is intrinsically broadband, the less than 100% correlation being due to the relative sensitivities of the two instruments and the width of the spectral index distribution. Our observations are consistent with the hypothesis that the spectral index of giant pulses is drawn from normal distribution of standard deviation 0.6, but with a mean that displays an evolution with frequency from −3.00 at 1382 MHz, to −2.85 at 192 MHz

The Equator Project Research School and Mentoring Network: Evaluated Interventions to Improve Equity in Geoscience Research

There is a well-documented racial and ethnic diversity crisis in Geography, Earth and Environmental Sciences (GEES) subjects in the Global North that leads to inequities in who does environmental research. The Equator project set out to increase participation and retention of UK-domiciled Black, Asian and minority ethnic students in GEES research by developing evidence-based, ring-fenced, fully remunerated interventions. These interventions were co-created with and informed by the voices of students and professionals within the GEES community, following a Theory of Change-based, action research approach. The Equator Research School brought together 30 Black, Asian and minority ethnic students in GEES, and 12 academics, professionals and mentors, from across the UK for a 5-day residential workshop in April 2022. The Research School was designed to facilitate network-building, improve awareness of research careers, enhance confidence in continuing in research, and strengthen a sense of belonging in GEES research for participants. The Equator Mentoring Network, which took place from January to May 2022, facilitated networking between 10 Black, Asian and minority ethnic student mentees and 20 academic and industry mentors involved in GEES subject areas. The overall goal of the Mentoring Network was to increase retention of Black, Asian and minority ethnic students into postgraduate research and to improve their overall experience. Evaluation of these interventions took the form of surveys to capture thoughts and reflections before, during and after interventions. Participants in both interventions provided very positive feedback; the majority of those involved felt a stronger sense of belonging and inclusion in GEES research and were more likely to consider a research career after taking part. The evaluation process showed unequivocally that the ring-fenced, discipline-specific, fully funded nature of the interventions was a critical factor in participant involvement. The work led to the development of recommendations for creating successful interventions for improving participation and retention in research, as well as templates for future, related EDI activities

Conjuring optimism in dark times: Education, affect and human capital

This paper analyses how the discursive construction, valuation and subjective experience of human capital is evolving in parallel with crises of capital as a world-system. Ideology critique provides tools for analysing policy ‘fictions’ that aim to sustain investment in human capital through education. Foucauldian analytical tools enable analysis of how human capital has become a project of self-appreciation and cultivation of positive psychological traits. We argue that the work of Lauren Berlant provides an important complement to these approaches and enables us to analyse how crises of capital are being lived as the cruelling of optimism about social mobility through investment in oneself as human capital. The paper points to an educational politics and pedagogy for living through infrastructural breakdown in darkly uncertain historical times

The mirage of the metropolis: city imaging in the age of digital chorography

Even as cities evolved geographically, the basis of city imaging (as codified by Kevin Lynch) remained relatively stable for over half a century. More recently, digitally driven transformations in urban life challenge the continued relevance of established city-imaging paradigms. Although digital navigation and mapping devices are readily at hand to neutralize any disorienting predicaments, the ability to image cognitively the wider urban environment remains integral to the construction of a meaningful sense of place. Towards the objective of reconciling city imaging with the place-making challenges of the contemporary metropolis, this paper explores the potential for innovating modes of urban mapping and representation. Specifically, the digital re-envisioning of the historical mapping practice of ‘chorography’ is positioned within Fredric Jameson’s challenge for a new aesthetic of cognitive mapping that enables the situational representation of the individual within the vaster totality. In doing so, the paper contributes to the wider adaptation of urban discourse to digitally propelled shifts in urban life

Reality beckons: metamodernist depthiness beyond panfictionality

It is often argued that postmodernism has been succeeded by a new dominant cultural logic. We conceive of this new logic as metamodernism. Whilst some twenty-first century texts still engage with and utilise postmodernist practices, they put these practices to new use. In this article, we investigate the metamodern usage of the typically postmodernist devices of metatextuality and ontological slippage in two genres: autofiction and true crime documentary. Specifically, we analyse Ruth Ozeki’s A Tale for the Time Being and the Netflix mini-series The Keepers, demonstrating that forms of fictionalisation, metafictionality and ontological blurring between fiction and reality have been repurposed. We argue that, rather than expand the scope of fiction, overriding reality, the metamodernist repurposing of postmodernist textual strategies generates a kind of ‘reality-effect’

Registered Ship Notes

https://digitalmaine.com/blue_hill_documents/1179/thumbnail.jp