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Keeling, John, Roger Fidler, Xianrong Luo, Adrian Fabris, Baohong Hou, and Nanshi Zeng. "Chinese CHIM – electro-geochemical survey of extensions to the Challenger Gold Mine, South Australia." ASEG Extended Abstracts 2006, no. 1 (December 2006): 1–4. http://dx.doi.org/10.1071/aseg2006ab082.
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Mireku-Gyimah, D., and R. Gyebuni. "Can Capital Injection Make Challenged Gold Projects in Ghana Economically Viable? – A Case Study." Ghana Mining Journal 19, no. 1 (June 30, 2019): 42–48. http://dx.doi.org/10.4314/gm.v19i1.5.
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Damang Gold Mine (DGM) in Ghana uses open pit mining technology to mine its gold deposit. It has an estimated mineable gold reserve of about 32 Mt exploitable for 8 years. As the gold price kept falling from 2013 and operating cost kept rising, the mine down sized its operations. But the operations became challenging due to poor performance of ageing mining equipment and processing plant, and the need for a new tailings dam. As the gold price stabilises, it could be gainful to invest capital to resolve the challenges and increase production. This study aims at investigating whether DGM would be economically viable if the intended investment is made assuming the gold price falls to US$ 32.15/g. The study estimates the required capital and annual operating cost to be US$89.49 M and US$100.84 M respectively. A cash flow analysis is carried out assuming no price escalation, discount rate of 20%, and applying the following investment laws of Ghana: royalty of 5% of gross revenue; straight line depreciation of capital expenditure over five years (20% per year); investment allowance of 5% in the first year only; loss carry forward; and corporate tax of 35%. The results give Net Present Value of US$82 723 720.28 and Internal Rate of Return of 41.13%, indicating profitability. Sensitivity analysis reveals that the project will continue to be profitable until the revenue falls below 24%, assuming all other economic parameters remain constant. The project will also continue to be profitable until the operating cost increases beyond 30%, assuming all other economic parameters remain constant. Risk analysis on the project indicates the project has 70% chances of success. DGM could invest the capital to mine its gold reserves because the mine will make profit provided cost is controlled and production level maintained to generate needed revenue. Keywords: Net Present Value, Internal Rate of Return, Sensitivity Analysis, Risk Analysis
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Powell, Wayne, Evren Yazgan, Michael Johnson, K. Aslıhan Yener, and Ryan Mathur. "Mineralogical Analysis of the Kestel Mine: An Early Bronze Age Source of Tin Ore in the Taurus Mountains, Turkey." Minerals 11, no. 1 (January 19, 2021): 91. http://dx.doi.org/10.3390/min11010091.
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Since its discovery in 1987, the Early Bronze Kestel Mine has been a topic of archaeological and geological controversy. The initial interpretation of the extensive marble-hosted galleries as the oldest known tin mine was challenged due to the low tin grade in remaining hematite-quartz veins, and it was suggested that Kestel was more likely mined for gold. Mineralogical analysis of the remaining mineralization was compared to a heavy mineral concentrate extracted from the soil preserved within the mine. The compositionally complex, arsenate-rich mineral assemblage from the mine sediment, contrasts with that of the remaining surface mineralization. Thus, the outcropping veins do not represent the nature of the extracted ore. Only one grain of gold was found in the heavy mineral concentrate, whereas cassiterite composed 1.5% of the sample. Cassiterite occurs in complex assemblages with arsenates, clays, hematite, quartz, and dolomite, bearing resemblance to hematite-arsenate tin mineralization that occurs near Kayseri, 60 km to the northeast. These findings indicate that although gold was a trace component of the Kestel ore, cassiterite was the mineral of interest to the Early Bronze Age miners, and that Kestel represents the earliest evidence thus far for an emerging pattern of local tin exploitation.
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Lynn, Nandy, and Bruce Hanson. "Designing a Cellular Organization: A Case Study of Sense Making at the National Prosperity Gold Production Group Ltd." South Asian Journal of Business and Management Cases 4, no. 1 (June 2015): 52–61. http://dx.doi.org/10.1177/2277977915574038.
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The country of Myanmar opened up to the outside world a little over three years ago. As part of that process, many of the industries in the country changed hands from state owned to private. Such was the case with large-scale gold mine, which had formerly been explored by a Canadian company with mining experience and restored under the government to indigenous control. In early September 2011, tender bids from citizens were invited for the concession rights of the mine. There had been about 300,000 illegal miners working in the restricted area, but were being kicked out as the new operator took over the mine. There were many challenges, each answered by trial and error of the National Prosperity Gold Production Group. One of the current challenges is to maintain continuous production to fulfil the payment schedule to the government. This case is a constantly unfolding situation of sense making that the National Prosperity is trying its best to successfully operate the mine.
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Zhao, Zijiang, Takaji Wakita, and Kotaro Yasui. "Inoculation of Plasmids Encoding Japanese Encephalitis Virus PrM-E Proteins with Colloidal Gold Elicits a Protective Immune Response in BALB/c Mice." Journal of Virology 77, no. 7 (April 1, 2003): 4248–60. http://dx.doi.org/10.1128/jvi.77.7.4248-4260.2003.
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ABSTRACT We established a simple and effective method for DNA immunization against Japanese encephalitis virus (JEV) infection with plasmids encoding the viral PrM and E proteins and colloidal gold. Inoculation of plasmids mixed with colloidal gold induced the production of specific anti-JEV antibodies and a protective response against JEV challenge in BALB/c mice. When we compared the efficacy of different inoculation routes, the intravenous and intradermal inoculation routes were found to elicit stronger and more sustained neutralizing immune responses than intramuscular or intraperitoneal injection. After being inoculated twice, mice were found to resist challenge with 100,000 times the 50% lethal dose (LD50) of JEV (Beijing-1 strain) even when immunized with a relatively small dose of 0.5 μg of plasmid DNA. Protective passive immunity was also observed in SCID mice following transfer of splenocytes or serum from plasmid DNA- and colloidal gold-immunized BALB/c mice. The SCID mice resisted challenge with 100 times the LD50 of JEV. Analysis of histological sections detected expression of proteins encoded by plasmid DNA in the tissues of intravenously, intradermally, and intramuscularly inoculated mice 3 days after inoculation. DNA immunization with colloidal gold elicited encoded protein expression in splenocytes and might enhance immune responses in intravenously inoculated mice. This approach could be exploited to develop a novel DNA vaccine.
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Olebogeng, David Daw. "Challenges and Opportunity of Housing for Black Miner in South Africa." European Journal of Economics and Business Studies 6, no. 1 (January 1, 2020): 28. http://dx.doi.org/10.26417/ejes.v6i1.p28-36.
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Mine companies are experiencing a change in the political system of the country (South Africa). This political change from apartheid government to the government of Democratic has brought about a totally different system of government; this change has led to the transformation of mines companies from employment section to housing of mineworkers from their operation system, how are the mines companies / houses dealing with this change? Changes in the political and economy of the gold mining in the 1970s - 1980s have prompted management to begin moving away from migratory labour and implementing alternative accommodation strategies for black mine workers. The paper aims to provide some understanding of the current housing situation and housing needs of mineworkers more than a decade after the abolition of the legislation which had shaped the living environments of mineworkers in South Africa, and will look at the different I alternative approaches for housing black mine workers and how they can afford housing.
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Peña-Graf, Felipe, Javier Órdenes, Ryan Wilson, and Alessandro Navarra. "Discrete Event Simulation for Machine-Learning Enabled Mine Production Control with Application to Gold Processing." Metals 12, no. 2 (January 25, 2022): 225. http://dx.doi.org/10.3390/met12020225.
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Interdisciplinary barriers separating data scientists and geometallurgists have complicated systematic attempts to incorporate machine-learning into mine production management; however, experiences in excavating a vein-hosted gold deposit within the Alhué region of Chile have led to methodological advances, which is the subject of the current paper. These deposits are subject to several challenges, from increasing orebody complexity and decreasing gold grades to the significant geological uncertainty that is intrinsic to these systems. These challenges then translate to mineral processing, which is already dealing with increased environmental and technological constraints. Geological uncertainty causes stockout risks that can be mitigated by the approach that is developed within this paper, which features alternate operational modes and related control strategies. A digital twin framework based on discrete event simulation (DES) and a customized machine-learning (ML) model is proposed to incorporate geological variation into decision-making processes, including the setting of trigger point that induces mode changes. Sample calculations that were based on a simulated processing plant that was subject to mineralogical feed changes demonstrated that the framework is a valuable tool to evaluate and mitigate the potential risks to gold mineral processing performance.
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Price, Brian M., Adriane L. Liner, Sukjoon Park, Stephen H. Leppla, Alfred Mateczun, and Darrell R. Galloway. "Protection against Anthrax Lethal Toxin Challenge by Genetic Immunization with a Plasmid Encoding the Lethal Factor Protein." Infection and Immunity 69, no. 7 (July 1, 2001): 4509–15. http://dx.doi.org/10.1128/iai.69.7.4509-4515.2001.
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ABSTRACT The ability of genetic vaccination to protect against a lethal challenge of anthrax toxin was evaluated. BALB/c mice were immunized via gene gun inoculation with eucaryotic expression vector plasmids encoding either a fragment of the protective antigen (PA) or a fragment of lethal factor (LF). Plasmid pCLF4 contains the N-terminal region (amino acids [aa] 10 to 254) of Bacillus anthracis LF cloned into the pCI expression plasmid. Plasmid pCPA contains a biologically active portion (aa 175 to 764) ofB. anthracis PA cloned into the pCI expression vector. One-micrometer-diameter gold particles were coated with plasmid pCLF4 or pCPA or a 1:1 mixture of both and injected into mice via gene gun (1 μg of plasmid DNA/injection) three times at 2-week intervals. Sera were collected and analyzed for antibody titer as well as antibody isotype. Significantly, titers of antibody to both PA and LF from mice immunized with the combination of pCPA and pCLF4 were four to five times greater than titers from mice immunized with either gene alone. Two weeks following the third and final plasmid DNA boost, all mice were challenged with 5 50% lethal doses of lethal toxin (PA plus LF) injected intravenously into the tail vein. All mice immunized with pCLF4, pCPA, or the combination of both survived the challenge, whereas all unimmunized mice did not survive. These results demonstrate that DNA-based immunization alone can provide protection against a lethal toxin challenge and that DNA immunization against the LF antigen alone provides complete protection.
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González-Valoys, Ana Cristina, Jonatha Arrocha, Tisla Monteza-Destro, Miguel Vargas-Lombardo, José María Esbrí, Efrén Garcia-Ordiales, Raimundo Jiménez-Ballesta, Francisco Jesús García-Navarro, and Pablo Higueras. "Environmental challenges related to cyanidation in Central American gold mining; the Remance mine (Panama)." Journal of Environmental Management 302 (January 2022): 113979. http://dx.doi.org/10.1016/j.jenvman.2021.113979.
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Macheke, Cecil, and Catherine Campbell. "Perceptions of HIV/AIDS on a Johannesburg Gold Mine." South African Journal of Psychology 28, no. 3 (September 1998): 146–53. http://dx.doi.org/10.1177/008124639802800304.
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Semi-structured interviews were conducted with 40 mine workers on a Johannesburg gold mine, focusing on workers' perceptions of health, HIV/AIDS and sexuality. The paper seeks to highlight a range of factors which might predispose mine workers to high-risk sexual behaviour, despite the fact that they had all attended HIV-education programmes. These factors are presented within a framework that views the process of sexual decision making as a debating process - in which competing facts and beliefs are weighed up against one another - within the context of a range of normative and social parameters. Firstly, attention is given to a number of pre-existing perceptions and doubts which may blunt the force of the facts that HIV educational messages seek to impart to this particular group of people. These include a lack of perceived urgency regarding the treatment of sexually transmitted diseases (STD's), a commitment to ‘flesh-to-flesh’ sex, a dislike of condoms, and faith in the ability of traditional healers to cure a range of STD's and possibly also HIV/AIDS. Secondly, attention is given to the normative context of sexuality, and in particular the way in which norms of masculinity predispose people to high-risk sexual behaviour. Finally, the paper focuses on some aspects of social and occupational life on the mines as the context within which sexual relationships are conducted. These include the phenomenon of single sex hostels, an acceptance of high levels of disease and accidents as the norm, and the use of alcohol. The paper concludes with a discussion of the challenges these findngs pose for a peer education programme which is shortly to be implemented in the mining context.
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Tsamenyi, Mathew, Trevor Hopper, and Shahzad Uddin. "Changing control and accounting in an African gold mine." Journal of Accounting & Organizational Change 13, no. 2 (June 5, 2017): 282–308. http://dx.doi.org/10.1108/jaoc-03-2014-0017.
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Purpose The paper aims to examine accounting changes in the Ashanti Gold Corporation (AGC) in Ghana over 120 years from pre-colonialism to recent times and whether the framework of management accounting transformations in Hopper et al. (2009) is applicable. Design/methodology/approach Mixed data sources are used, namely, interviews, some observations of practices, historical documentation, company reports and research papers and theses. The results are categorised according to the periods and contextual factors in the Hopper et al. framework to test whether it matches the data collected. Findings Despotic controls with minimal management accounting but stewardship accounting to the head office in London prevailed under colonialism. Upon independence state, capitalist policies descended into politicised state capitalism. Under nationalisation, the performance of mines deteriorated, and accounting became decoupled from operations. In the early 1980s, fiscal crises forced Ghana’s government to turn to the World Bank and International Monetary Fund for loans. This period marked a gradual transformation of AGC into a foreign multinational, organised along divisional lines and currently exercises despotic control through supply chain management that renders labour precarious and is neglectful of corporate social accounting issues. Research limitations/implications The work challenges neo-classical economic prescriptions and analyses of accounting in developed countries by indicating its neglect of the interests of other stakeholders, especially labour and civil society. Accounting is important for development but the article infers other forms may better serve the public interest. Originality/value The paper tests the Hopper et al. framework with respect to a large private multinational in the commodity sector over an extended period, which differs from the case studies drawn on originally.
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Mpanza, Mbalenhle, Elhadi Adam, and Raeesa Moolla. "Dust Deposition Impacts at a Liquidated Gold Mine Village: Gauteng Province in South Africa." International Journal of Environmental Research and Public Health 17, no. 14 (July 8, 2020): 4929. http://dx.doi.org/10.3390/ijerph17144929.
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The windy season brings numerous community complaints for gold mining companies situated in the Witwatersrand due to windblown dust from partially rehabilitated tailings storage facilities (TSFs). For communities encroaching onto TSFs, windblown dust is perceived as a health hazard and an environmental challenge. In a study conducted in 2017 by the Lawyers for Human Rights, the community of a gold mine village perceived tailings storage facility 6 (TSF6) and other surrounding tailings storage facilities which are partially rehabilitated to be a health and socio-economic threat. Since 2013, when a nearby gold mining company was liquidated, this community has been complaining about dust fallout. To validate the claims made by the community this paper reports on the dust deposition impacts, and respiratory illnesses risk posed by wind-blown generated dust. The study conducts an air quality assessment using dispersion modelling of windblown dust. Surface material from the TSFs was sampled, analysed for silica and heavy metal content using X-ray fluorescence (XRF) and inductively coupled plasma-mass spectrometry (ICP-MS) respectively. This study finds that PM10 dust fallout, high in silica and uranium content, could potentially pose health threats to the surrounding community. The study further shows that dust deposition is the highest in July–October, with TSF6 posing a nuisance while TSF1 represents a potential health threat owing to its particle size distribution for the surrounding gold mine village community. Potential receptors of the air pollution by dust in this study area include neighbouring property owners, business owners of the nearby shopping centre, the school and the clinic. This study further finds that sudden mine closure due to mine liquidation results in unrehabilitated tailings storage facilities which exacerbates dust deposition.
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Olajide-Ibiejugba, Abike O., Vusumuzi Nkosi, Funzani Takalani-Rathogwa, Joyce Shirinde, Janine Wichmann, Robin J. Green, and Kuku Voyi. "Allergy and Household Living Conditions among Adolescents Living near Gold Mine Tailing Dumps in the Gauteng and North West Provinces of South Africa." International Journal of Environmental Research and Public Health 19, no. 1 (December 23, 2021): 122. http://dx.doi.org/10.3390/ijerph19010122.
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This quantitative exploratory baseline study aimed to investigate whether allergy among adolescents was associated with household living conditions, including living near gold mine tailing dumps in South Africa. A questionnaire based on the International Study of Asthma and Allergies was used to collect information on allergy and household risk factors among adolescents (n = 5611). A chi-square test was applied to determine the relationship between community (exposed/unexposed) and confounding variables. Crude and adjusted odds ratios (ORs) and 95% confidence intervals (CI) were calculated using univariate and multiple logistic regression analysis (LRA) to estimate the likelihood of having doctor-diagnosed allergies. The overall prevalence of doctor-diagnosed allergies was 25.5%. The exposed communities had a higher prevalence of doctor-diagnosed allergies (26.97%) compared with the unexposed (22.69%) communities. The study found an association between doctor-diagnosed allergy and having fungus in the house, being female, currently having pets in and around the house, residing in the community for more than three years and living in communities located close to gold mine tailing dumps. Actions to implement buffer zones between gold mine tailing dumps and communities would support Sustainable Development Goals 3 (health) and 11 (sustainable cities and communities), while failing to address the current potential identified risk factors may pose a significant public health challenge. Local policymakers should also apply the precautionary principle to protect the health of children, especially with the location of human settlements relative to air pollution sources.
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Masloboev, Vladimir, Sergey Seleznev, Anton Svetlov, and Dmitriy Makarov. "Hydrometallurgical Processing of Low-Grade Sulfide Ore and Mine Waste in the Arctic Regions: Perspectives and Challenges." Minerals 8, no. 10 (October 7, 2018): 436. http://dx.doi.org/10.3390/min8100436.
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The authors describe the opportunities of low-grade sulfide ores and mine waste processing with heap and bacterial leaching methods. By the example of gold and silver ores, we analyzed specific issues and processing technologies for heap leaching intensification in severe climatic conditions. The paper presents perspectives for heap leaching of sulfide and mixed ores from the Udokan (Russia) and Talvivaara (Finland) deposits, as well as technogenic waste dumps, namely, the Allarechensky Deposit Dumps (Russia). The paper also shows the laboratory results of non-ferrous metals leaching from low-grade copper-nickel ores of the Monchepluton area, and from tailings of JSC Kola Mining and Metallurgical Company.
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Berhanu, Aklile, Rebecca L. Wilson, Dana L. Kirkwood-Watts, David S. King, Travis K. Warren, Susan A. Lund, Lindsay L. Brown, et al. "Vaccination of BALB/c Mice with Escherichia coli-Expressed Vaccinia Virus Proteins A27L, B5R, and D8L Protects Mice from Lethal Vaccinia Virus Challenge." Journal of Virology 82, no. 7 (January 16, 2008): 3517–29. http://dx.doi.org/10.1128/jvi.01854-07.
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ABSTRACT The potential threat of smallpox use in a bioterrorist attack has heightened the need to develop an effective smallpox vaccine for immunization of the general public. Vaccination with the current smallpox vaccine, Dryvax, produces protective immunity but may result in adverse reactions for some vaccinees. A subunit vaccine composed of protective vaccinia virus proteins should avoid the complications arising from live-virus vaccination and thus provide a safer alternative smallpox vaccine. In this study, we assessed the protective efficacy and immunogenicity of a multisubunit vaccine composed of the A27L and D8L proteins from the intracellular mature virus (IMV) form and the B5R protein from the extracellular enveloped virus (EEV) form of vaccinia virus. BALB/c mice were immunized with Escherichia coli-produced A27L, D8L, and B5R proteins in an adjuvant consisting of monophosphoryl lipid A and trehalose dicorynomycolate or in TiterMax Gold adjuvant. Following immunization, mice were either sacrificed for analysis of immune responses or lethally challenged by intranasal inoculation with vaccinia virus strain Western Reserve. We observed that three immunizations either with A27L, D8L, and B5R or with the A27L and B5R proteins alone induced potent neutralizing antibody responses and provided complete protection against lethal vaccinia virus challenge. Several linear B-cell epitopes within the three proteins were recognized by sera from the immunized mice. In addition, protein-specific cellular responses were detected in spleens of immunized mice by a gamma interferon enzyme-linked immunospot assay using peptides derived from each protein. Our data suggest that a subunit vaccine incorporating bacterially expressed IMV- and EEV-specific proteins can be effective in stimulating anti-vaccinia virus immune responses and providing protection against lethal virus challenge.
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Ofori-Sarpong, G., T. Okwaisie, and R. K. Amankwah. "Geometallurgical Studies on Gold Ore for Enhanced Comminution and Leaching." Ghana Mining Journal 19, no. 1 (June 30, 2019): 59–65. http://dx.doi.org/10.4314/gm.v19i1.7.
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Many gold processing plants are experiencing challenges as mining pits are becoming deeper, rocks are getting harder and more complex polymetallic and refractory ores are being encountered. The variations in the characteristics of ores lead to deviations from the established parameters, and these affect gold extraction efficiency. This paper presents a study where geological characteristics of the ore types from some mining pits were used to ascertain the influence of ore blends on improving the performances of comminution and leaching circuits. To achieve this, mineralogical, comminution, gravity recoverable gold and leaching investigations were conducted on fresh and weathered ore samples and their blends. Mineralogical study showed that the main rock types associated with the mine pits were dolerite, phyllites, conglomerates and sandstone. The dominant minerals were quartz, plagioclase, with traces of pyrites. The Crushability Work Indices of the rocks were between 30 and 37 KWh/t, which are generally higher than the maximum design value of 31.9 kWh/t, and this situation will pose throughput challenges in that section. The Bond Ball Mill Work Indices of the blends tested were between 16.4 kWh/t and 9.6 kWh/t and a blend ratio of 85% fresh and 15% weathered was found to have a Bond Ball Work Index almost equal to the design value of 14 kWh/t. With gold assays of 2.5 g/t for dolerite, 2.1 g/t for phyllite, 3.7 g/t for sandstone and 3.4 g/t for conglomerate, the gravity recoverable gold was in the order of sandstone 36% > phyllite (31.5%) > dolerite (29.5%) > conglomerate (18%). The overall gold recoveries were in the sequence of conglomerate (95%), sandstone (94%), phyllite (92%) and dolerite (87%). This information could be utilised in developing a proactive plant operations strategies for an operating plant in order to ultimately manage the plant and enhance achievement of set targets. Keywords: Geometallurgy; Ore Blends; Characterisation; Communition Circuit Performance; Gold Recovery
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Kandasamyhariramguptha, Karthikeyan. "Socio-economic Impact of Unsystematic Mine Closure: A case of Kolar Gold Fields." Academic Research Community publication 3, no. 2 (May 1, 2019): 26. http://dx.doi.org/10.21625/archive.v3i2.499.
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This paper aims to study the Socio-Economic impact of un-systematic mine closure on the community and the neighborhood which is completely dependent on the mining. The sudden closure of the mines will affect the community’s entire livelihood and has counter effect on health, employment, environment, population and economy. India as a developing nation with its rich minerals content contributes sufficient towards the economic growth of the mining industry but the livelihood of the mining workers and their family are always kept in high level of risk. The policies and acts to control un-planned mine closure and counter its effects on the community should be made strong by the government. Kolar Gold fields, Karnataka (KGF) which holds an history of 120 years of mining and second deepest mine in the world has been chosen for the study. It is one among of the mines in the country which experienced the un-systematic closure in 2001 and facing its effects due to mill tailings, land contamination and loss of employment till date. These issues and challenges faced by the people of KGF will be addressed and can be improved if the government, mining company and people shows their support and interest for reviving the town.
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Dominy, Glass, O’Connor, Lam, and Purevgerel. "Integrating the Theory of Sampling into Underground Mine Grade Control Strategies: Case Studies from Gold Operations." Minerals 9, no. 4 (April 17, 2019): 238. http://dx.doi.org/10.3390/min9040238.
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Grade control aims to deliver adequately defined tonnes of ore to the process plant. The foundation of any grade control programme is collecting high-quality samples within a geological context. The requirement for quality samples has long been recognised, in that these should be representative and fit-for-purpose. Correct application of the Theory of Sampling reduces sampling errors across the grade control process, in which errors can propagate from sample collection through sample preparation to assay results. This contribution presents three case studies which are based on coarse gold-dominated orebodies. These illustrate the challenges and potential solutions to achieve representative sampling and build on the content of a previous publication. Solutions ranging from bulk samples processed through a plant to whole-core sampling and assaying using bulk leaching, are discussed. These approaches account for the nature of the mineralisation, where extreme gold particle-clustering effects render the analysis of small-scale samples highly unrepresentative. Furthermore, the analysis of chip samples, which generally yield a positive bias due to over-sampling of quartz vein material, is discussed.
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Serra, Magda F., Amanda C. Cotias, Andreza S. Pimentel, Ana Carolina S. de Arantes, Ana Lucia A. Pires, Manuella Lanzetti, Jandir M. Hickmann, et al. "Gold Nanoparticles Inhibit Steroid-Insensitive Asthma in Mice Preserving Histone Deacetylase 2 and NRF2 Pathways." Antioxidants 11, no. 9 (August 26, 2022): 1659. http://dx.doi.org/10.3390/antiox11091659.
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Background: Gold nanoparticles (AuNPs) can inhibit pivotal pathological changes in experimental asthma, but their effect on steroid-insensitive asthma is unclear. The current study assessed the effectiveness of nebulized AuNPs in a murine model of glucocorticoid (GC)-resistant asthma. Methods: A/J mice were sensitized and subjected to intranasal instillations of ovalbumin (OVA) once a week for nine weeks. Two weeks after starting allergen stimulations, mice were subjected to Budesonide or AuNP nebulization 1 h before stimuli. Analyses were carried out 24 h after the last provocation. Results: We found that mice challenged with OVA had airway hyperreactivity, eosinophil, and neutrophil infiltrates in the lung, concomitantly with peribronchiolar fibrosis, mucus production, and pro-inflammatory cytokine generation compared to sham-challenged mice. These changes were inhibited in mice treated with AuNPs, but not Budesonide. In the GC-resistant asthmatic mice, oxidative stress was established, marked by a reduction in nuclear factor erythroid 2-related factor 2 (NRF2) levels and catalase activity, accompanied by elevated values of thiobarbituric acid reactive substances (TBARS), phosphoinositide 3-kinases δ (PI3Kδ) expression, as well as a reduction in the nuclear expression of histone deacetylase 2 (HDAC2) in the lung tissue, all of which sensitive to AuNPs but not Budesonide treatment. Conclusion: These findings suggest that AuNPs can improve GC-insensitive asthma by preserving HDAC2 and NRF2.
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Brierley, Corale L. "Biohydrometallurgy: What is its Future?" Advanced Materials Research 71-73 (May 2009): 3–10. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.3.
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Bioleaching/minerals biooxidation and bioremediation have been widely used commercially for heap/dump bioleaching of secondary copper sulfide ores, sulfidic-refractory gold concentrates and treatment of acid rock drainage. Technical and commercial challenges, identified in this paper, remain for bioleaching of primary sulfides and complex ores. New frontiers for the technology exist in processing massive sulfides, silicate-locked minerals and in the more distant future in-situ leaching. Decommissioning of cyanide heap leach operations and stabilizing mine wastes using biotechnology are opportunities requiring intensive and focused research, development and engineering efforts.
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Okereafor, G. U., M. E. Makhatha, L. Mekuto, and V. Mavumengwana. "Assessing the effectiveness of Hyparrhenia hirta in the rehabilitation of the ecosystem of a gold mine dump." E3S Web of Conferences 158 (2020): 04004. http://dx.doi.org/10.1051/e3sconf/202015804004.
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The mining of gold is associated with several environmental challenges such as acid mine drainage, release of toxic metals which are associated to tailing sediments and have adversely impacted human health and the ecosystem. With increasing global population that is faced with limited land resources for agricultural activities, there is need for land restoration through effective rehabilitation of contaminated soils. The introduction of Hyparrhenia hirta, an indigenous grass specie as a phytoremediation technique for in situ rehabilitation of degraded soil is not only an economically viable approach but also environmentally friendly. Hyparrhenia hirta being a tufted and wiry perennial grass that is invasive with deep root system often aid in stabilizing the ecosystem owing to their self-fertile and drought resistant potentials that support that prevalence in harsh conditions at mine dump sites. In this study, mine tailings at Gold One Mine, Ekuhurleni, South Africa were assessed for heavy metal contents at the same time analysing the uptake of such heavy metals by Hyparrhenia hirta grass specie. The total metal mean concentrations was high (4023.67 mg/kg) for Hyparrhenia hirta which absorbed more of the following mean metal concentrations: 46.10 mg/kg for Cu; 40.08 mg/kg for Zn; 859.12 mg/kg for Pb; 618.26 mg/kg for Cr; 151.70 mg/kg for Co and 2308.41 mg/kg for Ni. The tailings were strongly acidic with a pH range of 3.86 – 4.34. These heavy metals despite the acidic environments were successfully absorbed by Hyparrhenia hirta grass specie. Along these lines Hyparrhenia hirta was discovered reasonable for re-vegetation of mine tailings dump as it has the capacity to hold together tailings sediments against wind and water erosion.
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Ryl’nikova, Marina. "Strategy of energy efficiency enhancement for sustainable and environmentally balanced development of gold deposits at its final stage." E3S Web of Conferences 58 (2018): 01008. http://dx.doi.org/10.1051/e3sconf/20185801008.
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The article presents the rationale of the concept and defines the principles of keeping the production potential of a mining engineering system at the final stage of development to prevent a mine closure accompanied by a range of social, economic and environmental problems resulting from the disturbance of habitat, as well as lithosphere and hydrosphere parameters, etc. This concept can be implemented due to radically new geotechnology solutions aimed at the alteration of gold ore mining and processing technologies with the eventual disposal of wastes to mined-out areas. At the current stage of mining science advancement, energy efficiency and resource saving are inseparably connected with the sustainable use and conservation of non-renewable natural energy sources and transition to the use of technology-related energy sources regenerated in the course of mining. In this case, energy efficiency is viewed as economically feasible electricity consumption achieved at the current level of mining machinery and technology development and mandatory compliance with environmental safety requirements. Enhancement of energy efficiency envisages the minimization of energy consumption for mining processes while maintaining the scale of production and tackling the accompanying non-production challenges. For the first time, for gold deposit conditions the author proposes general methodological approaches, in combination with a certain level of details, to the problem of systematization and estimation of opportunities of renewable energy sources use in the course of implementation of mining processes. The importance of the mentioned problem solution for mining sciences is in finding the evidence of the fact that in the course of implementation of mining processes within the framework of a mine various technology-related renewable energy sources are formed, which were not taken into account earlier, while the discovered objective laws of the formation of these energy sources, which, depending on the design and technology parameters of mining operations, provide a choice of preferable technological solutions to minimize the consumption of external energy supply by a mine. Development of new technical and technological solutions on the conversion of technology-related energy sources into electricity, its accumulation and consumption for in-mine needs will significantly minimize the consumption of external power supply, and in general it will enhance energy efficiency of mining operations and involve deposits located in remote and hard-to-reach areas in production.
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Уханов, Иннокентий Сергеевич. "On Perspectives of Prospectors Activities Carried out by Natural Persons." ЖУРНАЛ ПРАВОВЫХ И ЭКОНОМИЧЕСКИХ ИССЛЕДОВАНИЙ, no. 1 (March 15, 2022): 147–52. http://dx.doi.org/10.26163/gief.2022.84.84.020.
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В статье рассматривается правовая проблема возрождения добычи золота и других драгоценных металлов физическими лицами. В настоящее время законодательство дозволяет такую деятельность только юридическим лицам, обладающим лицензией. Однако значительные объемы золота в России по-прежнему добываются физическими лицами незаконно. Теневой оборот золота на Дальнем Востоке достиг огромных масштабов. Разработан законопроект по легализации деятельности старателей и декриминализации золотодобывающей отрасли. Это позволит в ближайшие годы создать тысячи рабочих мест для местного населения и существенно увеличить добычу золота. The article deals with the challenge of reviving gold and other precious metals mining by individuals. Currently, the legislation allows such activity only to legal entities holding a license. However, significant amounts of gold in Russia continue to be mined illegally by individuals. The underground gold turnover in the Far East has reached enormous proportions. A draft law has been thus developed to legalize the activities of miners and decriminalize the gold mining industry. This will allow in the coming years to create thousands of jobs for the local population and significantly increase gold production.
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Riaz, Sundus, Nosheen Fatima Rana, Irshad Hussain, Tahreem Tanweer, Afrah Nawaz, Farid Menaa, Hussnain A. Janjua, et al. "Effect of Flavonoid-Coated Gold Nanoparticles on Bacterial Colonization in Mice Organs." Nanomaterials 10, no. 9 (September 7, 2020): 1769. http://dx.doi.org/10.3390/nano10091769.
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Multidrug resistance (MDR) has been a potentiator for the exploration of antibiotics. Nano drug delivery systems have opened new avenues to overcome this challenge. Although antibacterial nanocarriers are extensively realized, their effect on the bacteria residing inside the tissues and their toxicity is rarely explored. This study investigated the effects of flavonoid coated gold nanoparticles (FAuNPs) on the colonization of Enterococcus faecalis in the mouse liver and kidneys. Flavonoids were extracted from the leaves of Berberis lycium Royle and used to stabilize gold following a green synthesis approach. FAuNPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning transmission electron microscopy (STEM), X-ray powder diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). FAuNPs showed significantly higher reduction in bacterial counts in in-vitro and in-vivo in mice organs as compared to the free flavonoids owing to their biocompatibility and effectiveness.
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Scammacca, Ottone, Rasool Mehdizadeh, and Yann Gunzburger. "Territorial Mining Scenarios for Sustainable Land-Planning: A Risk-Based Comparison on the Example of Gold Mining in French Guiana." Sustainability 14, no. 17 (August 23, 2022): 10476. http://dx.doi.org/10.3390/su141710476.
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Mining can be the source and target of opportunities and threats of different natures exceeding the mine site perimeter, affecting the socio-ecological system and leading to social conflicts and entrepreneurial risks for mining companies. Hence, a mining project is a matter of land planning rather than a simple industrial object. Nevertheless, current mandatory risk and impact assessment methods are often performed on one project at a time, neglecting the coexistence of different mining activities and the socio-ecological vulnerability of the territory where mining takes place. This paper proposes an original risk-based approach to develop and compare different territorial mining scenarios (TMSs) to support land-planning strategies in mining territories, tested on the French Guiana gold mining sector. Five TMSs combining different mine types (e.g., legal artisanal, medium, large-scale mining, illegal mining) were developed for the same total amount of gold production at the watershed level. For each TMS, both accidental and ordinary risk scenarios were assessed through a GIS-based approach considering watershed socio-ecological vulnerability. Risks were finally weighted according to different stakeholders’ perception, and the TMSs were compared based on their global risk scores. Despite the multiple challenges highlighted, this paper highlights the feasibility of a methodological framework to support mining planning at the territory level.
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Prno, Jason, Matthew Pickard, and John Kaiyogana. "Effective Community Engagement during the Environmental Assessment of a Mining Project in the Canadian Arctic." Environmental Management 67, no. 5 (February 2, 2021): 1000–1015. http://dx.doi.org/10.1007/s00267-021-01426-5.
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AbstractThe Back River Project is an approved gold mine in Nunavut, Canada owned by Sabina Gold & Silver Corp. Sabina developed a comprehensive community engagement program during the environmental assessment phase of the Project to share information, receive and address local feedback and concerns, and develop productive relationships in support of Project advancement. This paper outlines Sabina’s engagement program, successes and challenges encountered from the perspective of a mineral developer, and insights obtained for effective community engagement in a Canadian Arctic context. The program has been commended by observers and is consistent with best practice models. Sabina’s experiences revealed the importance of engaging early and often using a context-specific approach; comprehensive record-keeping and reporting; the meaningful incorporation of community perspectives and Traditional Knowledge; and focusing on long-term relationships, partnerships, and local benefits. Effective community engagement subsequently played a key role in Sabina securing major licenses and permits for Project advancement.
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Simonetti, Igino, Federico Bruno, Roberta Fusco, Carmen Cutolo, Sergio Venanzio Setola, Renato Patrone, Carlo Masciocchi, et al. "Multimodality Imaging Assessment of Desmoid Tumors: The Great Mime in the Era of Multidisciplinary Teams." Journal of Personalized Medicine 12, no. 7 (July 16, 2022): 1153. http://dx.doi.org/10.3390/jpm12071153.
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Desmoid tumors (DTs), also known as desmoid fibromatosis or aggressive fibromatosis, are rare, locally invasive, non-metastatic soft tissue tumors. Although histological results represent the gold standard diagnosis, imaging represents the fundamental tool for the diagnosis of these tumors. Although histological analysis represents the gold standard for diagnosis, imaging represents the fundamental tool for the diagnosis of these tumors. DTs represent a challenge for the radiologist, being able to mimic different pathological conditions. A proper diagnosis is required to establish an adequate therapeutic approach. Multimodality imaging, including ultrasound (US), computed tomography (CT) and Magnetic Resonance Imaging (MRI), should be preferred. Different imaging techniques can also guide minimally invasive treatments and monitor their effectiveness. The purpose of this review is to describe the state-of-the-art multidisciplinary imaging of DTs; and its role in patient management.
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Winker, Kevin. "Chapter 1: Subspecies Represent Geographically Partitioned Variation, A Gold Mine of Evolutionary Biology, and a Challenge for Conservation." Ornithological Monographs 67, no. 1 (April 2010): 6–23. http://dx.doi.org/10.1525/om.2010.67.1.6.
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Wu, Kai Connie, Yu Zhong, and Jonathan Maher. "Predicting Human Infection Risk: Do Rodent Host Resistance Models Add Value?" Toxicological Sciences 170, no. 2 (May 20, 2019): 260–72. http://dx.doi.org/10.1093/toxsci/kfz116.
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AbstractUse of genetically engineered rodents is often considered a valuable exercise to assess potential safety concerns associated with the inhibition of a target pathway. When there are potential immunomodulatory risks associated with the target, these genetically modified animals are often challenged with various pathogens in an acute setting to determine the risk to humans. However, the applicability of the results from infection models is seldom assessed when significant retrospective human data become available. Thus, the purpose of the current review is to compare the outcomes of infectious pathogen challenge in mice with genetic deficiencies in TNF-α, IL17, IL23, or Janus kinase pathways with infectious outcomes caused by inhibitors of these pathways in humans. In general, mouse infection challenge models had modest utility for hazard identification and were generally only able to predict overall trends in infection risk. These models did not demonstrate significant value in evaluating specific types of pathogens that are either prevalent (ie rhinoviruses) or of significant concern (ie herpes zoster). Similarly, outcomes in mouse models tended to overestimate the severity of infection risk in human patients. Thus, there is an emerging need for more human-relevant models that have better predictive value. Large meta-analyses of multiple clinical trials or post-marketing evaluations remains the gold-standard for characterizing the true infection risk to patients.
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Greer, Margaret R. "Thine and Mine: The Spanish “Golden Age” and Early Modern Studies." PMLA/Publications of the Modern Language Association of America 126, no. 1 (January 2011): 217–24. http://dx.doi.org/10.1632/pmla.2011.126.1.217.
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Don Quixote, having shared the goatherds' rustic meal on his second sally, takes up a handful of acorns and launches into his lecture on the Golden Age: “Dichosa edad y siglos dichosos aquellos a quien los antiguos pusieron nombre de dorados, y no porque en ellos el oro, que en esta nuestra edad de hierro tanto se estima, se alcanzase en aquella venturosa sin fatiga alguna, sino porque entonces los que en ella vivían ignoraban estas dos palabras de tuyo y mío” ‘Blessed the time, and blessed the centuries, called by the ancients the Golden Age—and not because, then, the gold which we in our age of iron so value came to men's hands without effort, but because those who walked the earth in that time knew nothing of those two words, thine and mine.’ Bewildering as his harangue was for the listening goatherds, Don Quixote's introduction invites consideration of the location, ownership, and definition of the Spanish “Golden Age.” These aspects illuminate the challenge the period presents to early modern studies and vice versa.
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Comino, E., B. P. Miller, and N. J. Enright. "Soil seedbanks in natural and restored boxironbark forests at Stawell Gold Mine, Victoria." Pacific Conservation Biology 10, no. 1 (2004): 9. http://dx.doi.org/10.1071/pc040009.
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Natural communities have the capacity to regenerate themselves, and this functional ecosystem attribute must be regarded as a key indicator of success for revegetation programmes. The accumulation of species (and individuals) as dormant propagules in a soil seedbank, representing potential future states for the vegetation, is one possible index of revegetation success. Here, we investigate the soil seedbanks for five natural vegetation (Box-Ironbark forest) remnants, a topsoil stockpile and three revegetated mine-site areas associated with gold mining at Stawell (Victoria, Australia). The revegetation efforts largely date from 1987 and, in terms of their composition and structure, are relatively similar to natural vegetation remnants. Soil samples were treated with heat or smoke (plus control) and were monitored for seedling emergence, species composition and density in the glasshouse for 150 days. Seedling densities in treated seedbank samples were high (2 200 to 17 500 seedlings m-2) while species richness was low, ranging from 10 to 20 species per sample. Exotic species made up 22?61 % of emergents and 33?50% of species observed. Correlation of seedbank composition and density with chemical attributes of soils, and with above ground (extant) vegetation at sites showed few significant relationships. Total species richness and the proportion of exotic species varied significantly between natural bushland remnants and revegetation areas. Richness was highest, and the proportion of exotic species was lowest in natural bushland samples. Total emergent numbers and the density of exotic emergents did not vary significantly between remnant bushland and revegetation areas. Declining vigour of some woody species in revegetation sites that are well represented in the seedbank, including Acacia pycnantha and A. genistifolia, indicates that the reintroduction of fire might be an appropriate management practice to facilitate long-term recovery of a functional community on these revegetated surfaces, but the potential for the establishment of weed species from the seed-bank following fire may pose a challenge to management.
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Van Der Wel, Kjetil A., Olof Östergren, Olle Lundberg, Kaarina Korhonen, Pekka Martikainen, Anne-Marie Nybo Andersen, and Stine Kjaer Urhoj. "A gold mine, but still no Klondike: Nordic register data in health inequalities research." Scandinavian Journal of Public Health 47, no. 6 (July 10, 2019): 618–30. http://dx.doi.org/10.1177/1403494819858046.
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Aims: Future research on health inequality relies on data that cover life-course exposure, different birth cohorts and variation in policy contexts. Nordic register data have long been celebrated as a ‘gold mine’ for research, and fulfil many of these criteria. However, access to and use of such data are hampered by a number of hurdles and bottlenecks. We present and discuss the experiences of an ongoing Nordic consortium from the process of acquiring register data on socio-economic conditions and health in Denmark, Finland, Norway and Sweden. Methods: We compare experiences of data-acquisition processes from a researcher’s perspective in the four countries and discuss the comparability of register data and the modes of collaboration available to researchers, given the prevailing ethical and legal restrictions. Results: The application processes we experienced were time-consuming, and decision structures were often fragmented. We found substantial variation between the countries in terms of processing times, costs and the administrative burden of the researcher. Concerned agencies differed in policy and practice which influenced both how and when data were delivered. These discrepancies present a challenge to comparative research. Conclusions: We conclude that there are few signs of harmonisation, as called for by previous policy documents and research papers. Ethical vetting needs to be centralised both within and between countries in order to improve data access. Institutional factors that seem to facilitate access to register data at the national level include single storage environments for health and social data, simplified ethical vetting and user guidance.
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Pan, Zhenkai, Shaohua Hu, Chao Zhang, Tong Zhou, Guowei Hua, Yuan Li, and Xiaolin Lv. "Mechanical and Hydration Characteristics of Stabilized Gold Mine Tailings Using a Sustainable Industrial Waste-Based Binder." Materials 16, no. 2 (January 9, 2023): 634. http://dx.doi.org/10.3390/ma16020634.
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Sustainable resource utilization of tailings is a long-term challenge. Therefore, a novel waste-based binder is proposed in this study to stabilize/solidify gold mine tailings (GMTs). This binder is composed of fly ash (FA), ground blast furnace slag (GBFS), and metakaolin (MK) activated with mixed calcium carbide residue (CCR) as well as pure reagent grade chemical, sodium hydroxide (SH, NaOH), and plaster gypsum (PG, CaSO4·2H2O). The mechanical properties and hydration of stabilized tailings with curing period were investigated. Tests included triaxial compression test and nitrogen adsorption to evaluate the strength of the stabilized tailings and microstructure. The results show that the addition of the waste-based binder yields significant improvement in shear strength. Strain softening occurred for all cured samples, and a local shear band can be observed in all failed stabilized samples. Based on the relationship between strength and curing period, it can be speculated that the hydration reaction of the sample ends after around 40 days of curing. A bimodal pore-size distribution was observed in all solidified/stabilized samples. FTIR and 27Al MAS-NMR were used to analyze hydration products. The strength improvement of stabilized tailings was mainly attributed to the formation of ettringite and C–S–H gels after various polymerization reactions. These new hydrates bind tailings particles and fill the pores to form a more stable structure, which supplied superior mechanical properties. This paper can provide a theoretical basis for exploring the application of the industrial waste-based binder to modify the mechanical properties of gold tailings.
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Goyette-Desjardins, Guillaume, Cynthia Calzas, Tze Chieh Shiao, Axel Neubauer, Jennifer Kempker, René Roy, Marcelo Gottschalk, and Mariela Segura. "Protection against Streptococcus suis Serotype 2 Infection Using a Capsular Polysaccharide Glycoconjugate Vaccine." Infection and Immunity 84, no. 7 (April 25, 2016): 2059–75. http://dx.doi.org/10.1128/iai.00139-16.
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Streptococcus suisserotype 2 is an encapsulated bacterium and one of the most important bacterial pathogens in the porcine industry. Despite decades of research for an efficient vaccine, none is currently available. Based on the success achieved with other encapsulated pathogens, a glycoconjugate vaccine strategy was selected to elicit opsonizing anti-capsular polysaccharide (anti-CPS) IgG antibodies. In this work, glycoconjugate prototypes were prepared by couplingS. suistype 2 CPS to tetanus toxoid, and the immunological features of the postconjugation preparations were evaluatedin vivo. In mice, experiments evaluating three different adjuvants showed that CpG oligodeoxyribonucleotide (ODN) induces very low levels of anti-CPS IgM antibodies, while the emulsifying adjuvants Stimune and TiterMax Gold both induced high levels of IgGs and IgM. Dose-response trials comparing free CPS with the conjugate vaccine showed that free CPS is nonimmunogenic independently of the dose used, while 25 μg of the conjugate preparation was optimal in inducing high levels of anti-CPS IgGs postboost. With an opsonophagocytosis assay using murine whole blood, sera from immunized mice showed functional activity. Finally, the conjugate vaccine showed immunogenicity and induced protection in a swine challenge model. When conjugated and administered with emulsifying adjuvants,S. suistype 2 CPS is able to induce potent IgM and isotype-switched IgGs in mice and pigs, yielding functional activityin vitroand protection against a lethal challengein vivo, all features of a T cell-dependent response. This study represents a proof of concept for the potential of glycoconjugate vaccines in veterinary medicine applications against invasive bacterial infections.
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Buyela, Charles, Paul Njogu, Gideon Kikuvi, Joseph Kamau, Charles Mburu, and Dan Westervelt. "Occupational safety and health hazards in artisanal gold mines in western and Nyanza region, Kenya." Journal of Agriculture, Science and Technology 21, no. 2 (June 13, 2022): 55–65. http://dx.doi.org/10.4314/jagst.v21i2.5.
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Artisanal and small-scale gold mining (ASSGM) has experienced rapid growth due to mineral value and increasing poverty level in western and Nyanza regions in Kenya. The sub-sector has hazardous tasks occasioned by chemical exposures to such substances as mercury, physical strain and repetitive movements associated with extractive tasks challenge which vary from region to region and site to site. This paper reports findings of a study conducted on ASSGM in Kakamega (Roster mine and Ikolomani) and Migori (Masara-Suna West and Francis - Suna East) counties to assess workplace safety, health risk and good health practice among a population of one thousand four hundred (1400) miners and non-miners to identify and determine levels of health hazard in the sector. Descriptive cross-sectional design that involved stratified sampling technique with three broad stages was used: dividing mining and non-mining population in sub-groups (miners, foremen/supervisors, and head of households) at sites in administering to them research instrument using a simple random technique. Levels of airborne particulate matter (PM2.5 and PM10) were determined both at mining sites and away from mining sites using low cost monitor sensor (PA-11-SD Purple air sensor). The low-cost monitor sensor data was corrected using collocational data obtained using a continuous particulate monitor (BAM 1020) reference monitor in a similar location. SPSS version 25.0 was used to analyse qualitative data. The study found that common sources of hazards included handling elemental mercury with bare hands during amalgamation and exposure to fumes during refining raw sponge-like gold. Aaverage 24-hour variation cycle for (PM2.5 and PM10) was 117.11±14.47 and 195.18±15.35 μg/m3 in ambient air respectively at all mining sites. Histograms were used to present frequency distribution of variations for (PM2.5 and PM10) from mining activity. The average humidity and temperature variations of artisanal gold mining were in the range of (45-35) percentage (% RH) and (26-28)0C respectively. The study concluded that there were high risk cycle exposures to airborne particulate matter contaminants at artisanal gold mining sites as compared to non- mining sites. The study recommends that the county government should give priority to developing safe guidelines to ASSGM. The central government should also come up with guidelines on Occupational Safety and Health in artisanal gold mining to facilitate compliance with OSH requirements in the sector and offer effective participative training.
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Fitz-Henry, Erin. "Distribution without representation? Beyond the rights of nature in the southern Ecuadorian highlands." Journal of Human Rights and the Environment 12, no. 1 (March 31, 2021): 5–23. http://dx.doi.org/10.4337/jhre.2021.01.01.
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Despite the fact that Ecuador has arguably the most biocentric constitution in the world, deepening national investment in extractive development projects has left communities on the frontlines of these projects desperate for greater participation in decision-making processes currently monopolized by centralized ministries. The result has been a flourishing over the past two years of sub-national judicial and non-judicial challenges to strategic mining projects. Integral to these challenges is the constitutional language of rights for nature (Articles 71–4). Drawing on ethnographic research around the Río Blanco gold and silver mine in the southern highland province of Azuay, this article explores the diverse and surprising ways in which these environmental rights are being taken up as part of fundamental challenges to the decision-making monopolies of the Ministries of the Environment and of Mining. While numerous scholars of human and indigenous rights have recently lamented the fact that ‘rights-talk’ often appears unable to arrest or destabilize extractive imperatives, the case of Río Blanco suggests that, when embraced as part of wider social struggles for representation, rights-based approaches might be more potent than is currently being recognized. They may even encourage an important reorientation of some of the binaries that continue to preoccupy critical scholars of development.
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Bedell, Philip R., Frederick W. Firlotte, and Kevin Atherton. "A case record of tailings dam construction using residual soils." Canadian Geotechnical Journal 39, no. 2 (April 1, 2002): 409–16. http://dx.doi.org/10.1139/t01-094.
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For cost effective construction, it is often necessary to optimize the use of on-site materials. At the Omai Gold Mine in Guyana, South America, tropical residual soils are used for construction of the tailings storage facility. At present, the geotechnical characteristics of residual soils have not been investigated or reported to the extent that transported soils have been. Geotechnical design and construction with these tropical residual soils can present unique challenges and problems. This case record outlines the investigation and construction procedures for the facility and provides a sample of the typical geotechnical engineering properties exhibited by the native tropical soils. In addition, data on observed behaviour and experience obtained handling and placing the materials as well as the performance of the structures during construction are provided.Key words: tropical residual soils, geotechnical design, tailings storage facility.
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Velásquez, Germán, Daniel Carrizo, Stefano Salvi, Iván Vela, Marcial Pablo, and Agustín Pérez. "Tracking Cobalt, REE and Gold from a Porphyry-Type Deposit by LA-ICP-MS: A Geological Approach towards Metal-Selective Mining in Tailings." Minerals 10, no. 2 (January 28, 2020): 109. http://dx.doi.org/10.3390/min10020109.
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High-resolution mineral characterization performed on mine material from a giant porphyry copper deposit shows that critical and precious metals, such as cobalt, lanthanum, gold, silver, and tellurium, are concentrated in pyrite in the form of visible micro-inclusions, invisible mineral nano-inclusions, and trace metals in the mineral lattice. Visible and invisible inclusions consist of Ag-Au-Te sulfosalt and monazite-(La) particles. Trace metal concentrations grade up to 24,000 g/t for cobalt, up to 4000 g/t for lanthanum, and up to 4 g/t for gold. Pyrite, considered a waste material, is removed from the valuable copper ore material and sent to the tailings. Thus, tailings with high contents of pyrite can represent a prime target to explore for critical metals in the porphyry copper mining operations, transforming it into a new source of supply for critical metals. We propose that high-resolution mineral characterization is the key to evolve from a quasi-single-metal (copper) operation to a multi-metals business by developing metal-selective mining. To address this challenge, we coined the Metal-Zone concept to identify zones enriched in a specific metal within a mineral deposit, instead of zones enriched in an ore mineral.
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Radini, A., M. Tromp, A. Beach, E. Tong, C. Speller, M. McCormick, J. V. Dudgeon, et al. "Medieval women’s early involvement in manuscript production suggested by lapis lazuli identification in dental calculus." Science Advances 5, no. 1 (January 2019): eaau7126. http://dx.doi.org/10.1126/sciadv.aau7126.
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During the European Middle Ages, the opening of long-distance Asian trade routes introduced exotic goods, including ultramarine, a brilliant blue pigment produced from lapis lazuli stone mined only in Afghanistan. Rare and as expensive as gold, this pigment transformed the European color palette, but little is known about its early trade or use. Here, we report the discovery of lapis lazuli pigment preserved in the dental calculus of a religious woman in Germany radiocarbon-dated to the 11th or early 12th century. The early use of this pigment by a religious woman challenges widespread assumptions about its limited availability in medieval Europe and the gendered production of illuminated texts.
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Li, Fabiana. "Engineering responsibility." Focaal 2011, no. 60 (June 1, 2011): 61–73. http://dx.doi.org/10.3167/fcl.2011.600106.
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Focusing on a controversial gold mining project in Chile, this article examines how engineers and other mining professionals perceive and help shape Corporate Social Responsibility initiatives. Compensation agreements, environmental management, and community relations programs rest on what I call a logic of equivalence that makes the environmental consequences of mining activity commensurate with the mining companies’ mitigation plans. For example, legal codes enable engineers to measure, compare, and reconcile the costs and benefits of a project. However, the law is neither fixed nor uncontestable, and companies must respond to increased public scrutiny and the growing demands of communities, governments, and international actors. In Chile, campaigns against mining focused on the presence of glaciers at the mine site and the project’s possible effects on water availability. By introducing new moral dimensions to debates over corporate responsibility, these campaigns challenged established strategies of commensuration and existing ethical guideposts.
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L, Pavithra, and Rekha D. "INTERNET OF THINGS – SURVEY ON RESEARCH CHALLENGES." Asian Journal of Pharmaceutical and Clinical Research 10, no. 13 (April 1, 2017): 464. http://dx.doi.org/10.22159/ajpcr.2017.v10s1.20513.
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Internet of things (IoTs) is a stage where consistently gadgets get to be more intelligent, consistently preparing gets to be savvy, and consistently correspondence gets to be educational. While the IoTs is as yet looking for its own particular shape, its belongings have as of now gazed in making mind-blowing strides as a widespread arrangement media for the associated situation. Engineering particular study does dependably clear the compliance of related field. The absence of general building information is in a matter of seconds standing up to the scientists to overcome the extent of IoTs driven methodologies. This writing overviews IoTs situated structures that are sufficiently able to enhance the comprehension of related apparatus, innovation, and approach to encourage engineer’s necessities. Specifically or in a roundabout way, the displayed designs propose to take care of genuine issues by building also, organization of intense IoTs ideas. Encourage, explore challenges have been investigated to solidify the blank inside the present examples of plans to goad the scholastics additionally, wanders get included into searching for the possible course outs to appropriate the right constrain of IoTs. A principle commitment of this review paper is that it outlines the current best in class of IoTs designs in different spaces deliberately.
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Mganda, Veri. "CHALLENGES ON THE PRACTICES OF CORPORATE SOCIAL RESPONSIBILITY IN THE MINING SECTOR IN TANZANIA: THE CASE STUDY OF BULYANHULU AND GEITA GOLD MINE." Business Education Journal 2, no. 1 (October 25, 2016): 1–14. http://dx.doi.org/10.54156/cbe.bej.2.1.84.
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Corporate Social Responsibility (CSR) is important and strategic businesses practice which is not only beneficial to the community, corporate shareholders and other stakeholders but also to corporate sustainability. Corporate Social Responsibility in the mining sector calls for an inclusion of social and environmental issues while pursuing economic prosperity of that particular country. For a country endowed with minerals like Tanzania, stringent regulations are needed. Incompetence of the managerial practice to implement CSR in their on-going operations, international capital and global companies have been identified as major causes for environmental pollution and growing environmental activism. There is a wide criticism among stakeholders in the sector demanding to develop plans and establish a clear strategy so as to reverse the current practices where CSR is simply being applied as a branding and marketing strategy by these companies. The literature review especially on the mining sector hardly revealed any impressive implementation and compliance requirements for CSR, particularly from environmental perspective for the best of national interests. Therefore this study examines the challenges in the practices for CSR from the environmental perspective in the mining sector in Tanzania. The methodology used in the study is meta-analysis in which various studies on CSR implementation have been reviewed. The findings on the ground indicate that there are serious challenges to comply with CSR in protecting the environment. Conclusions drawn have relevance for the real life systems and academia, particularly on integrating responsible leadership and ethical thinking in business curricular
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Bainton, Nicholas A., Chris Ballard, Kirsty Gillespie, and Nicholas Hall. "Stepping Stones Across the Lihir Islands: Developing Cultural Heritage Management in the Context of a Gold-Mining Operation." International Journal of Cultural Property 18, no. 1 (February 2011): 81–110. http://dx.doi.org/10.1017/s0940739111000087.
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AbstractLarge-scale resource extraction projects often create obstacles for the protection, maintenance, and inheritance of indigenous cultural heritage. In this article we detail some of the challenges and opportunities arising from our collaborative partnership with the community of the Lihir Islands in Papua New Guinea, which is seeking to establish, inform, and resource a formal cultural heritage management program in the context of a large-scale gold-mining operation. The general approach to this collaborative venture involves the application of a specific development tool, the Stepping Stones for Cultural Heritage program. This consultative process is innovative in both Melanesia and the context of resource extraction, but also more generally within the field of cultural heritage. We describe the outcomes of this process and some of the initial pilot projects, one of which was based on the recording of traditional Lihirian songs. We also argue that while the mine places greater pressure upon Lihirian cultural heritage, it also presents Lihirians with the opportunity to realize a vision of their cultural future that is beyond the reach of many other indigenous communities.
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Melnichenko, I. A., and Yu V. Kirichenko. "Development of Zoning Method for Man-Made Massifs." Mining Industry Journal (Gornay Promishlennost), no. 3/2021 (July 20, 2021): 116–22. http://dx.doi.org/10.30686/1609-9192-2021-3-116-122.
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Contemporary mining industry is a complex system that is constantly expanding both in terms of explored sources of mineral raw materials and in terms of developing new approaches to mining and processing of minerals. Such a buildup in the scope of tasks set for the industry, as well as the technical progress, lead to various issues related to the quality, quantity and rational use of mineral raw materials. Rationalization, in its turn, should be carried out in a phased manner through the use of comprehensive measures, one of which is reclamation of man-made wastes, represented by waste rocks, tailings, slags, dust, etc. In addition, this approach simultaneously resolves several other important challenges the industry is facing, e.g. increasing the environmental safety of mining regions and increasing the economic feasibility of production by extracting additional components from waste materials. The scope of application of such a solution to the challenge of rationalizing production is immense and can be implemented at many deposits located in the territory of the CIS due to the presence of huge volumes of waste generated by mining raw materials. These wastes were accumulated because of the absence of full-fledged technologies to extract useful components from the rock mass in the past as well as other requirements to ore conditioning than those acting today. For example, in the Republic of Bashkortostan, the overburden dumps and off-balance ores that have been created by mining enterprises amount to more than 1 billion tons, hydraulic-mine dumps of processing plants reach 50 million tons, manmade waters exceed 9 million m3 annually. At the same time, the amount of useful components contained in these man-made deposits can be up to 1.5 million tons for copper, 2 million tons for zinc, about 100 tons of gold as well as significant amounts of other associated components, including various non-metallic formations.
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Johnson, Curtis L., David A. Browning, and Neil E. Pendock. "Hyperspectral Imaging Applications to Geometallurgy: Utilizing Blast Hole Mineralogy to Predict Au-Cu Recovery and Throughput at the Phoenix Mine, Nevada." Economic Geology 114, no. 8 (December 1, 2019): 1481–94. http://dx.doi.org/10.5382/econgeo.4684.
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Abstract The Phoenix mine and predecessor operations in north-central Nevada have produced an aggregate of 5.2 Moz of gold and 550 million pounds of copper from an Eocene-aged Au-Cu porphyry-related skarn. The complex skarn mineralogy intimately associated with ore-grade mineralization poses significant challenges to blasting, mining, comminution, and process operations. These challenges are rooted in highly variable silicate mineralogy, which manifests as fine-grained, submillimeter grain-size, generally green colored rocks that inhibit accurate identification in the field. Prior to this study, all mineralogical data utilized in Phoenix mine ore control were sourced from blast hole cuttings mapped by ore control geologists in the field—the standard practice at many modern mine sites. At Phoenix, a direct link between mineralogy and mill performance was recognized; however, mineralogical data captured in the field was not sufficient to optimize process operations. To address this, it was determined that analytical work was necessary to quantify fine-grained mineralogy of variable ore types. A visible-near and short-wave infrared (VNIR-SWIR) hyperspectral imaging system provided the ideal tool, as it allows near real-time mineralogical data acquisition and semiquantitative determination of mineral abundances. Multiple iterative studies were conducted to prove that hyperspectral imaging of Phoenix ore types provides results suitable for process optimization. This six-month study described here included hyperspectral imaging of 3,008 blast hole cuttings samples from three pits, and 877 crusher feed, rougher feed, and rougher tails samples. Hyperspectral feature extractions derived from mill samples were paired with associated mill performance data and used to build predictive Au-Cu recovery, grade, and throughput models using multiple linear regression, partial least squares, and deep learning techniques with R-correlation values to observed data of 0.56 to 0.71. Blast hole hyperspectral data were then applied to recovery, grade, and throughput models to calculate predicted recoveries and throughputs that were spatially kriged with excellent correlations to geologic features. The application of VNIR-SWIR hyperspectral imaging to blast hole cuttings is a powerful predictive and diagnostic geometallurgical tool in operations where silicate mineralogy has a strong impact on process operations.
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Anzulović Šanta, Željka, Anja Ognjenović, Frane Božić, Boška Hrvačić, Ines Glojnarić, Snježana Čužić, and Maja Antolić. "Retrospektivna procjena učinka nintedaniba u mišjem modelu plućne fibroze." Veterinarska stanica 54, no. 4 (December 30, 2022): 395–406. http://dx.doi.org/10.46419/vs.54.4.4.
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Pulmonary function tests (PFTs) routinely implemented in clinics are the first step in the diagnosis of idiopathic pulmonary fibrosis. Evaluation of PFTs in the mouse model of pulmonary fibrosis accompanied by histological readouts may improve the clinical predictability of new therapeutic candidates. Forced vital capacity (FVC) is considered the most predictive of restrictive pulmonary disorders. This study aimed to test the improvement of PFT in mice lung fibrosis induced by treatment with an approved substance nintedanib, considered the gold standard. The hypothesis that treatment in animal models will demonstrate similar effects as in humans in the most relevant clinical outcomes was tested. Two experimental designs were enrolled in this study, a preventive regimen, with treatment initiation from the day of the challenge; and a therapeutic regimen, starting on day 7 postchallenge when fibrotic changes are present in the lungs. Experiments were terminated at two different time points, at 14 and 21 days postchallenge. C57BL/6 mice were administered with bleomycin (BLM) intranasally and treated with nintedanib from day 0 to day 14 or from day 7 until day 21. Fourteen or 21 days after the BLM challenge, PFTs were assessed using the in vivo invasive lung function measurement system Buxco® Pulmonary Function Test (PFT) (DSI™, New Brighton, USA). Histological evaluation was performed as a modified Ashcroft score. The bleomycin challenge induced a significant decrease of FVC in both experiments. However, nintedanib treatment given in both regimens significantly improved lung functionality. These findings were confirmed with histological analysis of the Ashcroft scoring system, modified by Matsuse. In conclusion, a good correlation between functional test parameters and the clinical effect of nintedanib was shown in both experiments: the preventive regimen was sampled 14 days post-challenge and the therapeutic regimen 21 days post-challenge. Based on these findings, the implementation of PFTs could be a good platform to increase the translational value of the model and potential new treatments.
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Terracciano, Rossana, Aobo Zhang, E. Brian Butler, Danilo Demarchi, Jason H. Hafner, Alessandro Grattoni, and Carly S. Filgueira. "Effects of Surface Protein Adsorption on the Distribution and Retention of Intratumorally Administered Gold Nanoparticles." Pharmaceutics 13, no. 2 (February 5, 2021): 216. http://dx.doi.org/10.3390/pharmaceutics13020216.
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The heterogeneous distribution of delivery or treatment modalities within the tumor mass is a crucial limiting factor for a vast range of theranostic applications. Understanding the interactions between a nanomaterial and the tumor microenvironment will help to overcome challenges associated with tumor heterogeneity, as well as the clinical translation of nanotheranostic materials. This study aims to evaluate the influence of protein surface adsorption on gold nanoparticle (GNP) biodistribution using high-resolution computed tomography (CT) preclinical imaging in C57BL/6 mice harboring Lewis lung carcinoma (LLC) tumors. LLC provides a valuable model for study due to its highly heterogenous nature, which makes drug delivery to the tumor challenging. By controlling the adsorption of proteins on the GNP surface, we hypothesize that we can influence the intratumoral distribution pattern and particle retention. We performed an in vitro study to evaluate the uptake of GNPs by LLC cells and an in vivo study to assess and quantify the GNP biodistribution by injecting concentrated GNPs citrate-stabilized or passivated with bovine serum albumin (BSA) intratumorally into LLC solid tumors. Quantitative CT and inductively coupled plasma optical emission spectrometry (ICP-OES) results both confirm the presence of particles in the tumor 9 days post-injection (n = 8 mice/group). A significant difference is highlighted between citrate-GNP and BSA-GNP groups (** p < 0.005, Tukey’s multiple comparisons test), confirming that the protein corona of GNPs modifies intratumoral distribution and retention of the particles. In conclusion, our investigations show that the surface passivation of GNPs influences the mechanism of cellular uptake and intratumoral distribution in vivo, highlighting the spatial heterogeneity of the solid tumor.
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Barton, Gábor. "Simulating Environmental Impacts Based On The Example Of Roşia Montană." Journal of Environmental Geography 8, no. 3-4 (December 1, 2015): 1–10. http://dx.doi.org/10.1515/jengeo-2015-0007.
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Abstract One of the challenges of modern terrain modelling methods is to incorporate non-existing, planned features in the output. Remote sensing based solutions can only detect structures and shapes that are already present in the environment. In order to assess the impacts of a planned development on the surrounding landscape properly it is inevitable to solve this issue. In addition to the environmental, social and economic consequences, mining activities, especially open cast mining will also leave significant scars on the landscape. These can not only have a visual effect but also impact local weather conditions by changing winds, precipitation patterns. The current paper demonstrates a collection of methods and techniques able to cope with the various challenges that arise when modelling the landscape impacts of such developments. The experiments were performed in the area of Roşia Montană, where a Canadian company plans to create the largest open cast gold mine in Europe. The results of the terrain modelling process allow for the quantification of the estimated impacts on the terrain and the land cover of the area caused by the mining project. The presented methodology and visualisation tools can also facilitate the decision support mechanisms making the communication ‘more understandable’ amongst stakeholders; information meetings and public hearings involving organizing groups at any level. Obtaining the results required the development of several unconventional techniques especially in terrain modelling and visual landscape simulation, involving the combination of sometimes very different base methods.
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Chai, Hongyan, Xueyong Wang, Zhimin Liu, and Yuehan Zhao. "Study on the removal of amyloid plaque by nano-gold in the treatment of neurodegenerative disease-alzheimer’s disease." Materials Express 11, no. 7 (July 1, 2021): 1038–44. http://dx.doi.org/10.1166/mex.2021.1992.
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As a complex neurological disease, the treatment of Alzheimer’s disease (AD) is a global challenge. Compared with traditional drug therapy, a novel therapeutic tool, inorganic nanoparticles combined with photothermal therapy (PTT) can decompose amyloid β-protein (Aβ) fibrils and inhibit Aβ aggregation, alleviating AD symptoms. In this study, MoS2@Au NPs composite nanoparticles were constructed by combining sulfhydryl-modified Au NPs and MoS2 nanosheets. In vitro experiments showed that the composite nanoparticles could degrade insoluble Aβ fibers to soluble monomers and alleviate neurotoxicity. Additionally, the excellent biocompatibility and biosafety of MoS2@Au NPs reduced the damaging effects on nerve cells, and the AD model mice benefited from the treatment with MoS2@Au NPs, which significantly improved their learning and cognitive abilities and thus reduced the disease. More importantly, MoS2@Au NPs combined with PTT effectively curbed the inflammatory response and slowed down the course of AD.
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Marther, Sibanda Sindiso, Mapuva Jephias, and Tambura Prudence. "Assessing the Role of Artisanal and Small-Scale Mining in Poverty Alleviation: A Case of Barn Mining Area, Ward 25 Matopo: Matabeleland South Province." Environmental Management and Sustainable Development 9, no. 2 (May 8, 2020): 109. http://dx.doi.org/10.5296/emsd.v9i2.16990.
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This paper sought to assess the role of artisanal and small-scale mining in poverty alleviation, focusing on Barn mining area ward 25 Matopo (Matabeleland South Province). The study adopted a mixed method approach in data collection, comprising the use of questionnaires, interview guides, observation tools and focus group discussions. The study found that ASM contributes to income generation and employment creation and has become a major source of livelihood in many mineral resource endowed areas of Zimbabwe. It was concluded that ASM as an economic activity has improved livelihoods as the income affords the miners an improved standard of life in addition to the ability to buy agricultural inputs and sending their children to school. However, several challenges associated with ASM were identified. These include lack of financial and institutional assistance, gold wars and other unfound agreements made between miners and claim owners. Loss of life in mine accidents, spread of sexually transmitted diseases are some of the negative impacts identified. The study recommended that for the benefits of ASM to be realised in terms of poverty alleviation, ASM activities should be decriminalized and financial support availed to miners.