82 research outputs found

    Tailings Dust Emissions

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    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.Existingequipmentandpersonnelareadequatetochangefromthecurrentmagnesiumchloridetreatmenttoavinylcopolymertreatment.Currentyearlytreatmentsusingthemagnesiumchloridecostapproximately110,000. 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 240,000-720,000assuming13applicationsperyearacrossthe400acrearea;thuschangingtoavinylcopolymertreatmentwillsave720,000 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

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    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

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    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

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    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

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    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

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

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    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

    Reality beckons: metamodernist depthiness beyond panfictionality

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    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’

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

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    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

    Registered Ship Notes

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

    31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

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    Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
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