Journal articles: 'Platinum mines'

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Benya, Asanda. "Going underground in South African platinum mines to explore women miners’ experiences." Gender & Development 25, no. 3 (2017): 509–22. http://dx.doi.org/10.1080/13552074.2017.1379775.

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BARNES, SARAH-JANE, and WOLFGANG D. MAIER. "Platinum-group Elements and Microstructures of Normal Merensky Reef from Impala Platinum Mines, Bushveld Complex." Journal of Petrology 43, no. 1 (2002): 103–28. http://dx.doi.org/10.1093/petrology/43.1.103.

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Vogt, D. "A borehole radar system for South African gold and platinum mines." South African Journal of Geology 109, no. 4 (2006): 521–28. http://dx.doi.org/10.2113/gssajg.109.4.521.

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Ionescu, Lavinel G. "ANTONIO DE ULLOA, DISCOVERER OF PLATINUM." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 6, no. 7 (1998): 1–6. http://dx.doi.org/10.48141/sbjchem.v6.n7.1998.4_1998_2.pdf.

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Don Antonio de Ulloa, a member of a distinguished Spanish family, was born in 1716 and died in 1795. He studied physics and mathematics and was a member of many scientific societies, including the Academy of Sciences of Paris and the Royal Society of London. He traveled widely in Europe and the Americas and occupied many important positions, including those of Frigate Captain, Commander of the Royal Squadron of the Spanish Armada, Goverment of Huancavelica -Peru, Louisiana, and Florida. In l735, while a member of a scientific expedition sent by the Spanish and French governments to South America to measure a degree of meridian in Quito, close to the equator, he discovered platinum in the mines of Lavadero or wash gold in the district of Choco.

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Ngwenya, Sam. "CEO compensation, corporate governance, and performance of listed platinum mines in South Africa." Corporate Ownership and Control 13, no. 2 (2016): 408–16. http://dx.doi.org/10.22495/cocv13i2clp8.

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Executive compensation has been studied extensively in the past three decades, yet the relationship between company performance and executive compensation continues to be a debated topic judging from the number of articles in academic literature. The main objective of this study was to determine the relationship between CEO compensation, corporate governance and financial performance of listed platinum mines in South Africa. The results of the study indicated no statistics significant relationship between CEO compensation and the financial performance variables ROE and ROA. The results also indicated a positive relationship between some corporate governance variables such as board size and proportion number of independent non-executive directors, but found no statistic significant relationship between CEO compensation and proportion number of female board members.

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van Schoor, Michael, and Andrew Binley. "In-mine (tunnel-to-tunnel) electrical resistance tomography in South African platinum mines." Near Surface Geophysics 8, no. 6 (2010): 563–74. http://dx.doi.org/10.3997/1873-0604.2010021.

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7

Neingo, P. N., T. Tholana, and A. S. Nhleko. "A comparison of three production rate estimation methods on South African platinum mines." Resources Policy 56 (June 2018): 118–24. http://dx.doi.org/10.1016/j.resourpol.2017.11.006.

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8

Buys, Pieter W., Merwe Oberholzer, and Toy Prinsloo. "Estimating Scale Efficiency Of Platinum-Mining Companies Environmental Performance: A South African Perspective." International Business & Economics Research Journal (IBER) 10, no. 12 (2011): 11. http://dx.doi.org/10.19030/iber.v10i12.6646.

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The purpose of the study is to develop a data envelopment analysis (DEA) model to estimate the relative scale efficiency of platinum-mining companies environmental performance. South African platinum-mines were used to demonstrate the model, which uses environmental performance indicators as the input variables in order to generate mineral extraction and financial performances as the output variables. The input variables considered were greenhouse gas emissions, water usage and energy usage, while the output variables were platinum production, return on equity and return on assets. The contribution of the study is that a DEA model was developed that could identify relatively efficient companies that could act as benchmarks with regard to environmental issues in the mining sector. A further contribution is that the study concluded that platinum-mining companies tend not to achieve economies of scale, where the companies that are relatively larger in size tend to operate on a scale that is too large and companies that are physically relatively smaller in size tend to operate on a scale that is too small.

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9

Jones, M. Q. W. "Heat flow in the Bushveld Complex, South Africa: implications for upper mantle structure." South African Journal of Geology 120, no. 3 (2017): 351–70. http://dx.doi.org/10.25131/gssajg.120.3.351.

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Abstract Geothermal measurements in South Africa since 1939 have resulted in a good coverage of heat flow observations. The Archaean Kaapvaal Craton, in the central part of South Africa, is the best-studied tectonic domain, with nearly 150 heat flow measurements. The greatest density of heat flow sites is in the Witwatersrand Basin goldfields, where geothermal data are essential for determining refrigeration requirements of deep (up to 4 km) gold mines; the average heat flow is 51 ± 6mWm-2. The Bushveld Complex north of the Witwatersrand Basin is an extensive 2.06 Ga ultramafic-felsic intrusive complex that hosts the world’s largest reserves of platinum. The deepest platinum mines reach ~2 km and the need for thermal information for mine refrigeration engineering has led to the generation of a substantial geothermal database. Nearly 1000 thermal conductivity measurements have been made on rocks constituting the Bushveld Complex, and borehole temperature measurements have been made throughout the Complex. The temperature at maximum rock-breaking depth (~2.5 km) is 70°C, approximately 30°C higher than the temperature at equivalent depth in the Witwatersrand Basin; the thermal gradient in the Bushveld Complex is approximately double that in the Witwatersrand Basin. The main reason for this is the low thermal conductivity of rocks overlying platinum mines. The Bushveld data also resulted in 31 new estimates for the heat flux through the Earth’s crust. The overall average value for the Bushveld, 47 ± 7 mW m-2, is the same, to within statistical error, as the Witwatersrand Basin average. The heat flow for platinum mining areas (45 mW m-2) and the heat flux into the floor of the Witwatersrand Basin (43 mW m-2) are typical of Archaean cratons world-wide. The temperature structure of the Kaapvaal lithosphere calculated from the Witwatersrand geothermal data is essentially the same as that derived from thermobarometric studies of Cretaceous kimberlite xenoliths. Both lines of evidence lead to an estimated heat flux of ~17 mW m-2 for the mantle below the Kaapvaal Craton. The estimated thermal thickness of the Kaapvaal lithosphere (235 km) is similar to that defined on the basis of seismic tomography and magnetotelluric studies. The lithosphere below the Bushveld Complex is not significantly hotter than that below the Witwatersrand Basin. This favours a chemical origin rather than a thermal origin for the upper mantle anomaly below the Bushveld Complex that has been identified by seismic tomography studies and magnetotelluric soundings.

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10

Coetzee, L. C., and M. Ramonotsi. "Applying StarCS RNMPC with Real-Time Optimiser to Pilanesberg Platinum Mines Primary UG2 Milling Circuit." IFAC-PapersOnLine 49, no. 20 (2016): 78–83. http://dx.doi.org/10.1016/j.ifacol.2016.10.100.

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11

Stewart, Paul. "Accelerated mechanisation and the demise of a mass-based labour force? Platinum mines in South Africa." Review of African Political Economy 42, no. 146 (2015): 633–42. http://dx.doi.org/10.1080/03056244.2015.1087397.

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12

Ballhaus, Christian G. "Potholes of the Merensky Reef at Brakspruit Shaft, Rustenburg platinum mines; primary disturbances in the magmatic stratigraphy." Economic Geology 83, no. 6 (1988): 1140–58. http://dx.doi.org/10.2113/gsecongeo.83.6.1140.

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13

Campbell, G. "High resolution aeromagnetic mapping of "loss-of-ground" features at platinum and coal mines in South Africa." South African Journal of Geology 109, no. 4 (2006): 439–58. http://dx.doi.org/10.2113/gssajg.109.4.439.

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14

Shaw, William George, Marc Mathews, and Johan Marais. "Holistic analysis of the effect on electricity cost in South Africa’s platinum mines when varying shift schedules according to time-of-use tariffs." Journal of Energy in Southern Africa 30, no. 4 (2019): 26–40. http://dx.doi.org/10.17159/2413-3051/2019/v30i4a5675.

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In the past the cost of electricity was not a significant concern and was not common practice for mining companies to consider peak time-of-use (TOU) tariffs for their shift schedules. It has become more prevalent, as TOU tariffs continue increasing, to consider energy saving important. A study was carried out to analyse the mining operation of a South African deep-level platinum mine in respect of integrated load management, shift changes and TOU schedules. This was achieved by thoroughly analysing energy consumers, mine operational schedules and their interconnectedness. A specific mining system was analysed as a case study and a maximum savings scenario was determined, using the methodology formulated. The maximum savings scenario schedule change resulted in a 1.3% cost reduction. System improvements had an additional potential reduction effect of 8.4%, which was primarily the result of a reduction in compressors’ power consumption. The implications of the proposed schedule adjustments necessitated a realistic scenario. The realistic scenario had an effective financial reduction of 0.7%. The realistic schedule change, however, opened the door for large system operational improvements, which could increase the reduction potential by 7.6%. The study methods described illustrate the potential implications of integrated load management and operational schedule optimisation on the power demand and cost savings in the mining industry, specifically focusing on deep-level platinum mines.

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Evans, Allison D., and Rudra Sil. "The Dynamics of Labor Militancy in the Extractive Sector: Kazakhstan’s Oilfields and South Africa’s Platinum Mines in Comparative Perspective." Comparative Political Studies 53, no. 6 (2019): 992–1024. http://dx.doi.org/10.1177/0010414019879715.

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This article investigates why, in two very different regimes, similarly high levels of labor militancy are evident in Kazakhstan’s oilfields and South Africa’s platinum belt. It also explores the common dynamics leading up to the massacres at Zhanaozen (2011) and Marikana (2012). The hypothesis-generating most different systems comparison highlights the challenges of labor relations where extraction at fixed sites combines with volatile prices and shareholder pressures in a globalized economy to raise the stakes for business, labor, and state. Also significant are blockages in existing channels for bargaining linked to quiescent unions. These jointly necessary conditions account for increased militancy in extractive industries in Kazakhstan and South Africa. To account for the Zhanaozen and Marikana massacres, timing and sequence are considered. Both standoffs came later in the strike wave, prompting impatient state and business elites to criticize the protests as “criminal” acts, and priming security personnel to employ violent repression.

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Stewart, Paul. "The Material Basis of Worker Subjectivity: Rock Drill Operators on the South African Platinum Mines in Historical Perspective." Journal of Asian and African Studies 51, no. 2 (2015): 143–56. http://dx.doi.org/10.1177/0021909615605532.

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17

Pithouse, Richard. "Frantz Fanon: Philosophy, Praxis, and the Occult Zone." Journal of French and Francophone Philosophy 24, no. 1 (2016): 116–38. http://dx.doi.org/10.5195/jffp.2016.761.

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In 2011, Achille Mbembe asserted that “the human has consistently taken on the form of waste within the peculiar trajectory race and capitalism espoused in South Africa.” He added that the end of apartheid had shifted rather than undone the lines of exclusion and dispute. Since the massacre on the platinum mines in 2012 it has become widely accepted that the state is resorting to repressive measures to enforce these lines and contain the dispute that they occasion. With notable exceptions academic philosophy, and theory more broadly, has offered remarkably little illumination of the widening distance between the promise of national liberation and democracy and the often bitter realities of contemporary South Africa. [i] Achille Mbembe ‘Democracy as Community Life’ Johannesburg Workshop in Theory & Criticism, 2011 http://jwtc.org.za/volume_4/achille_mbembe.htm

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Grushina, O. V., та A. I. Grushina. "THE HISTORY OF ECONOMIC DEVELOPMENT OF THE NORTHERN TERRITORIES - THE GOLD OF YAKUTIA: KОCHULUKAN AND YNYKCHAN IN THE POST-WAR PERIOD (MEMOIRS OF THE OWNER)". History: facts and symbols, № 3 (14 вересня 2021): 15–33. http://dx.doi.org/10.24888/2410-4205-2021-28-3-15-33.

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The paper is devoted to a part of A. M. Ozhigov‟s memoirs, recently found in the family archives of the authors. The memoirs describe the working conditions at the gold mines of the Dzhugdzhurzoloto trust in 1947. The post-war period required an urgent replenishment of the state gold reserves, which was reflected in the Decree of the Council of Ministers of the USSR (1946) on increasing the production of gold and platinum in the country. As a result, the Special Main Directorate of the USSR Ministry of Internal Affairs (Glavspetstsvetmet) has been created. The activity of this Directorate was focused on the search and exploration of new deposits, technical modernization and improvement of working conditions in mines This period of profound post-war crisis of gold industry, entirely determined by the war efforts, was characterized by a high share of manual labor, labor of prisoners and special settlers, low qualifications of workers and arduous living conditions. Here, we have evaluated reliability of the above memoirs using a comparative historical method. The factual knowledge of the memoirs was confirmed in open official sources. However, these sources are rather scarce in terms of human relations directly in gold mines and newly discovered areas. New names and circumstances of the everyday life of gold prospectors developing the deposit of the Kоchulyukan spring, brightly presented in the memoirs of A. M. Ozhigov, reveal the unknown details of the Soviet history of the industrial development of the northern territories. The psychological aspect of the recollections, expressed in the author's vivid subjectivism in relation to the organizers of the works (managers), also brightly show the opposition of the "worker-boss" type. Scanned copies of A. M. Ozhigov‟s memoirs are kept in the V. F. Vereshchagin Museum of Local Lore, Bodaibo town, Irkutsk region.

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Dunbar Moodie, T. "‘Igneous’ means fire from below: the tumultuous history of the National Union of Mineworkers on the South African platinum mines." Review of African Political Economy 42, no. 146 (2015): 561–76. http://dx.doi.org/10.1080/03056244.2015.1088432.

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20

Tumo Charles Maloka. "A Critical Appraisal of Dismissals at the Behest of a Third Party: The Impact of the Constitutional Labour Rights." Obiter 42, no. 1 (2021): 105–25. http://dx.doi.org/10.17159/obiter.v42i1.11059.

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The pivotal judgments on dismissals at the behest of a third party – East Rand Proprietary Mines Ltd v UPUSA, Lebowa Platinum Mines v Hill, NUMSA v Hendor Mining Supplies a Division of Marschalk Beleggings (Pty) Ltd, TSI Holdings (Pty) Ltd v NUMSA, NUPSAW obo Mani v National Lotteries Board and NUMSA v High Goal Investments t/a Chuma Security Services – deeply implicate discrimination in all its manifestations, accountability, gendered precariousness and social justice. This contribution explores the focal questions raised in recent times concerning the fairness of a dismissal at the instance of a third party. First, there are fundamental points relating to the constitutional and statutory protection of security of employment. Secondly, there are those familiar problems often associated with substantive and procedural fairness that surface here under the guise of questioning the disciplinary power of the employer. In this context, inroads into managerial prerogative and disciplinary procedure are amplified where there has been no fault on the part of the employee and no breakdown of the trust relationship, or where the employee has been disciplined, but not dismissed and the employer did not want to terminate the employee’s employment but was coerced by the third party to do so. Thirdly, there is the thorny issue of the reason behind the third-party demand and the related issue of intolerability caused by the targeted employee. And finally, there is the issue of striking in support of a demand for dismissal of a co-employee.

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Sanou, Soufiane, Abdoul Salam Ouedraogo, Arsène Hema, et al. "Criterium pencil mines as an alternative to platinum rods (Inoclic) in achievement of the antibiogram in agar medium for countries with limited resources?" Annales de Biologie Clinique 78, no. 1 (2020): 54–60. http://dx.doi.org/10.1684/abc.2020.1519.

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Tseane-Gumbi, Lisebo Agnes, and Victor Ojakorotu. "Muddling Through Destination Marketing: Experiences from the North West Province, South Africa." April 2021, Volume 10(2) (April 30, 2021): 592–607. http://dx.doi.org/10.46222/ajhtl.19770720-120.

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Globalization propagates the dominance of internationalization and the shortage of resources to strengthen competitive edges is apparent. The 4th Industrial Revolution (4IR) in developing countries is still a wish rather than a reality, putting more strains on destinations located in developing countries and hampers destination marketing strategies. This paper examines the rationale for destinations’ confusion over their positioning status, using the North West Province as a reference point. The paper adopts a qualitative design which was sourced through reviews of destination marketing strategies, white paper tourism policy and provinces’ tourism websites. The reviews were further analyzed using content analysis. The results indicate that the province positions itself as a cultural and heritage destination and that cultural and heritage activities account for less than 5%. Also, the results indicate a mismatch of the province’s strong attributes and marketing positioning strategy. The paper concludes that the province would become the hub of destination marketing and huge patronage if it focuses on its strengths and main competitive edge, namely the social activities, shopping, eating out, nightlife, and natural attractions such as the sun, dunes, and platinum mines.

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Sarsenbayev, N. B., B. K. Sarsenbayev, Т. S. Aubakirova, J. T. Aimenov, and K. S. Abdiramanova. "Phase Composition and Structure-Formation of the Low-Clinkered Floured Cements." Eurasian Chemico-Technological Journal 16, no. 4 (2014): 333. http://dx.doi.org/10.18321/ectj2.

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<p>We have carried out studies on the production of low-clinkered floured cements (LCFC) on the basis of natural and technogenic waste. The research on optimizing the compositions, strength, durability and performance properties of low-clinkered floured cements (LCFC) was carried out. Therefore, we studied the new products in the process of hydration of mechanically activated multi-component cements in the presence of technogenic wastes of the industry (waste of limestone crushing at opencast mines, metallurgical and phosphoric slag) and surface-active reagents (SAR) (superplasticizer S-3); as well as the development of compositions of high-strength and technological sorts of cement concretes. Thus, the low-clinkered floured cements developed by us based on industrial technogenic waste that meet the modern requirements, i.e. they improve physical-mechanical characteristics of the material and positively influence the ecological situation and allow decreasing the cost of final product. The physico-chemical research of the processes of hydration of low-clinkered floured cements with additive of superplasticizer S-3 were carried out by modern methods using X-ray diffract-meter D8ADVANCE (Bruker company) with Cu-radiation and synchronous thermo-analyzer STA 409 PC Luxx (Netzsch, Germany) at exposure mode of 10 º/min in the platinum crucibles in the air conditions.</p>

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Oshin, I. O., and James H. Crocket. "Noble metals in Thetford Mines ophiolites, Quebec, Canada; Part II, Distribution of gold, silver, iridium, platinum, and palladium in the Lac de l'Est volcano-sedimentary section." Economic Geology 81, no. 4 (1986): 931–45. http://dx.doi.org/10.2113/gsecongeo.81.4.931.

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25

Eales, H. V., W. J. de Klerk, and A. R. Butcher. "The cyclic unit beneath the UG1 chromitite (UGIFW unit) at RPM Union Section Platinum Mine—Rosetta Stone of the Bushveld Upper Critical Zone?" Mineralogical Magazine 54, no. 374 (1990): 23–43. http://dx.doi.org/10.1180/minmag.1990.054.374.03.

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AbstractThe UG1 Footwall unit is a layered pyroxenite-norite-leuconorite-anorthosite sequence between the Middle Group 4 and Upper Group 1 chromitites of the Upper Critical Zone, and is c. 300 m thick at Rustenburg Platinum Mines, Union Section, where it shows an oscillatory fluctuation in whole-rock Mg/(Mg + Fe), Cr/Co, Ni/V and Fe/Ti ratios with stratigraphic height. This permits subdivision into 8 sub-cycles which match a subdivision based on cyclical variations in orthopyroxene and feldspar compositions. Constituent pyroxene grains of pyroxenites, norites and leuconorites alike contain rounded and embayed plagioclase inclusions in abundance. Sr-isotope disequilibrium prevails in some samples between the orthopyroxene and feldspar populations. Chemical and isotopic data support a model of pulsatory injection of limited volumes of a more primitive, mafic liquid into a resident column of depleted residua, from which sodic labradorite and Mg-poor bronzite were crystallizing. The depleted liquid is equated with the supernatant liquid residuum of buried cumulates (Sric. 0.7054) and the primitive liquid with magma parental to the UG1-UG2 lineage (Sri ⩾ 0.7068). The increase in leucocratic character of the 300 m column, with height, is attributed to the rising of low-density liquids enriched in the components of feldspar during separation of the pyroxenites. Deposition of the UG1 chromitite layers is attributed to mixing of a major influx of primitive liquid with a feldspathic residuum at the top of the UG1 Footwall unit. There is no evidence to indicate the participation of a discrete A-type liquid (Irvine and Sharpe, 1982) in this process.

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Geldenhuys, G., E. R. Rohwer, Y. Naudé, and P. B. C. Forbes. "Monitoring of atmospheric gaseous and particulate polycyclic aromatic hydrocarbons in South African platinum mines utilising portable denuder sampling with analysis by thermal desorption–comprehensive gas chromatography–mass spectrometry." Journal of Chromatography A 1380 (February 2015): 17–28. http://dx.doi.org/10.1016/j.chroma.2014.12.062.

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Teran, Santiago, Maria Camara Jurado, and Juan Antonio Nuñez Sobrino. "A Patient with an Ileocecal MiNEN and a Synchronous Squamous Non-Small-Cell Lung Cancer: Case Report and Review of the Literature." Case Reports in Oncological Medicine 2021 (March 31, 2021): 1–8. http://dx.doi.org/10.1155/2021/8896254.

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Mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) are rare tumors composed of two different histological components, one of which is of a neuroendocrine origin. Given its suggested underdiagnosis and consequent low prevalence, no clear diagnostic and treatment guidelines are available, and treatment usually follows regimens similar to that of the most aggressive component. On the other hand, multiple primary tumors (MPTs) are also rare neoplastic entities that usually confer a challenge regarding treatment options, for a regimen that comprises both the primary and the synchronous/metachronous malignancy should be used. Here, we discuss the challenging diagnostic and therapeutic management of a patient with an ileocecal MiNEN that presented along with a synchronous squamous non-small-cell lung cancer (SQ-NSCLC). The patient presented with intestinal obstruction symptoms for which he underwent an emergency resection of the ileocecal MiNEN. An initial CT scan showed an additional lung mass later identified as an SQ-NSCLC after bronchoscopy biopsy analysis. Given the rapid hepatic metastatic progression, palliative platinum-based chemotherapy was initiated, with an adequate response of the local and metastatic lesions of the MiNEN, but suggested platinum resistance and progression of the pulmonary neoplasm. Second-line treatment with pembrolizumab directed for the SQ-NSCLC was initiated; however, it was stopped after immune-mediated toxicities developed. A third-line chemotherapy scheme with carboplatin/gemcitabine was initiated, but central nervous system (CNS) progression developed, with the patient dying 11 months after initial diagnosis.

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Grant Cawthorn, R. "Re-evaluation of magma compositions and processes in the uppermost Critical Zone of the Bushveld Complex." Mineralogical Magazine 60, no. 398 (1996): 131–48. http://dx.doi.org/10.1180/minmag.1996.060.398.09.

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AbstractA detailed geochemical study is presented of the uppermost Critical Zone, especially of the footwall and hanging wall to the Merensky Reef, at Impala Platinum Mines in the Bushveld Complex. The approximately 100 m-thick sequence below the Merensky Reef consists of 13 distinct layers which have sharp boundaries. They are adcumulates with varying proportions of cumulus plagioclase, orthopyroxene and chromite.Experimental studies on the composition of coexisting orthopyroxene liquid indicate that the magma which produced this sequence contained between 4 and 6% MgO. The magma from which the Merensky Reef formed was more evolved than the footwall magma.Significant variations exist for both the En content of orthopyroxene and mg# number of whole-rock analyses in short vertical sections. Pyroxenite and norite always have higher values than anorthosite. Extremely sharp breaks in these values correlate with changes in modal proportions, and argue against both significant fractionation within the studied interval, and infiltration metasomatism. Quantitative modelling shows that the entire footwall section could have contained pyroxene with a uniform primary composition of En82, and that all the variation now observed reflects the effect of reaction with trapped magma.Two independent methods for determining the proportion of trapped liquid are presented, based on mg# number and incompatible element abundances. Both yield a uniform proportion in all samples of approximately 10%. Immiscible sulphide liquid from the Merensky Reef can be shown to have infiltrated downwards for <5 m, despite its high density contrast with silicate magma, very low viscosity and low crystallization temperature. Residual silicate magma would have had even more restricted mobility. The migration of residual liquid or fluid through pothole structures in the floor of the Merensky Reef is not supported by the present data.

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Grebenyuk, Pavel S. "Russian Gold Mining Output in 1901-1917: A Source Studies Aspect." Herald of an archivist, no. 3 (2018): 679–91. http://dx.doi.org/10.28995/2073-0101-2018-3-679-691.

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This paper explores the problem of gold mining output in the Russian empire in 1901-1917 drawing on published and archival data. The aim of the study is to clarify indicators of gold mining production, since in the leading studies the data vary due to the peculiarities of metal accounting. It draws on published materials and archival documents of the State Institute for Design of Enterprises of Gold and Platinum Industry of the Glavzoloto of the People's Commissariat of Nonferrous Metallurgy (Giprozoloto), prepared in 1944 as a ‘Collection of Materials on the Gold Industry: 1493 - 1943’ and stored in the State Archive of the Magadan Region. Materials of the Giprozoloto Institute contain calculations of gold production in Russia and the USSR from 1745 to 1943, as well as technical and economic information on national gold mining industry in the early 20th century. The analysis shows that gold mining indices in scientific literature and sources are given according to data from gold log-books or gold-smelting laboratories. Gold log-books did not reflect the volume of actual mining, they only showed the gold registered in mines; moreover, some gold was withheld, and then came in to laboratories for alloy. Accounting for metal in the gold-smelting laboratories showed higher and more accurate production figures, since it included artisanal mining gold. However, as the source study demonstrates, figures of gold production in 1901-1917 according to the Giprozoloto Institute (805.4 tons) and according to L.B. Kafengauz (814.6 tons) based on data of gold-smelting laboratories and incorporated volumes of uncleaned bullion gold entered in there. The results of the study change the views on the volume of gold mining in Russia in this period that prevail in the historiography. It should be noted, that according to calculations, confirmed indicators of industrial production of chemically pure gold in Russia in 1901-1917 amounted to 682.5 tons. Final figures of gold industry of the period in amount of chemically pure gold obtained in gold-smelting laboratories corresponded to indices of value of gold production used in the analysis industry dynamics, and is considered correct, when compared with the USSR gold-mining indices.

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Economou-Eliopoulos, Maria, Magdalena Laskou, Demetrios Eliopoulos, Ifigeneia Megremi, Sofia Kalatha, and George Eliopoulos. "Origin of Critical Metals in Fe–Ni Laterites from the Balkan Peninsula: Opportunities and Environmental Risk." Minerals 11, no. 9 (2021): 1009. http://dx.doi.org/10.3390/min11091009.

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As the global energy sector is expected to experience a gradual shift towards renewable energy sources, access to special metals in known resources is of growing concern within the EU and at a worldwide scale. This is a review on the Fe–Ni ± Co-laterite deposits in the Balkan Peninsula, which are characterized by multistage weathering/redeposition and intense tectonic activities. The ICP-MS analyses of those laterites indicated that they are major natural sources of Ni and Co, with ore grading from 0.21 to 3.5 wt% Ni and 0.03 to 0.31 wt% Co, as well as a significant Sc content (average 55 mg/kg). The SEM-EDS analyses revealed that fine Fe-, Ni-, Co-, and Mn-(hydr)oxides are dominant host minerals and that the enrichment in these elements is probably controlled by the post-formation evolution of initial ore redeposition. The paucity of rare earth element (REE) within the typical Fe–Ni laterite ore and the preferential occurrence of Co (up to 0.31 wt%), REE content (up to 6000 mg/kg ΣREE), and REE-minerals along with Ni, Co, and Mn (asbolane and silicates) towards the lowermost part of the Lokris (C. Greece) laterite ore suggest that their deposition is controlled by epigenetic processes. The platinum-group element (PGE) content in those Fe–Ni laterites, reaching up to 88 μg/kg Pt and 26 μg/kg Pd (up to 186 μg/kg Pd in one sample), which is higher than those in the majority of chromite deposits associated with ophiolites, may indicate important weathering and PGE supergene accumulation. Therefore, the mineralogical and geochemical features of Fe–Ni laterites from the Balkan Peninsula provide evidence for potential sources of certain critical metals and insights to suitable processing and metallurgical methods. In addition, the contamination of soil by heavy metals and irrigation groundwater by toxic Cr(VI), coupled with relatively high Cr(VI) concentrations in water leachates for laterite samples, altered ultramafic rocks and soils neighboring the mining areas and point to a potential human health risk and call for integrated water–soil–plant investigations in the basins surrounding laterite mines.

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Cabral, A. R., G. Beaudoin, R. Kwitko-Ribeiro, B. Lehmann, J. C. Polonia, and M. Choquette. "PLATINUM PALLADIUM NUGGETS AND MERCURY-RICH PALLADIFEROUS PLATINUM FROM SERRO, MINAS GERAIS, BRAZIL." Canadian Mineralogist 44, no. 2 (2006): 385–97. http://dx.doi.org/10.2113/gscanmin.44.2.385.

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Gervilla, Fernando, Javier García-Guinea, and Luis Fermín Capitán-Vallvey. "Platina in the 18th century: mineralogy of the crude concentrate used in the first modern attempts at refining platinum." Mineralogical Magazine 84, no. 2 (2020): 289–99. http://dx.doi.org/10.1180/mgm.2020.3.

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AbstractA platina sample brought to Spain in the last quarter of the 18th century is nowadays exhibited at the National Museum of Natural Sciences in Madrid. It originated from the ancient Mineralogical Museum of the School of Applied Chemistry at El Turco Street in Madrid and most probably corresponds to the material used by François Chabaneau for his experiments to purify platinum metal in the late 18th century. The sample is a heavy-mineral concentrate consisting of Pt–Fe alloys and gold nuggets associated with ilmenite–hematite, chromian spinel, goethite and minor quartz, sphene, rutile, magnetite, hornblende, garnet, calcite, pyrite, native bismuth and bismite. The Pt–Fe alloys exhibit a characteristic composition (81.97–90.75 wt.% Pt and 5.08–10.81 wt.% Fe with minor amounts of Cu, Os, Ir, Ru, Rh and Pd) and mineralogy of solid inclusions (abundant inclusions of Ir alloy as well as Os alloy, laurite–erlichmanite, bowieite, tulameenite and undetermined Pt–Pd–Ir–Rh antimonides and tellurides) that are very similar to those Pt–Fe alloys currently mined in western Colombia (the Chocó Department). These features allow us to discuss the provenance of the sample (probably from the proximal or medial reaches of any of the Chocó rivers) and evaluate the suitability of the Chabaneau's method for purifying platina. Our results show that the method became effective only with platina samples depleted or lacking iridium.

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Lim, Megan S. C., Jill Murray, Robert J. Dowdeswell, Judith R. Glynn, and Pam Sonnenberg. "Unnatural Deaths in South African Platinum Miners, 1992–2008." PLoS ONE 6, no. 9 (2011): e22807. http://dx.doi.org/10.1371/journal.pone.0022807.

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Sepadi, Maasago M., Martha Chadyiwa, and Vusumuzi Nkosi. "Platinum Mine Workers’ Exposure to Dust Particles Emitted at Mine Waste Rock Crusher Plants in Limpopo, South Africa." International Journal of Environmental Research and Public Health 17, no. 2 (2020): 655. http://dx.doi.org/10.3390/ijerph17020655.

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The South African mining industry is one of the largest producers of platinum (Pt) in the world. Workers in this industry are exposed to significant amounts of dust, and this dust consists of particles sizes that can penetrate deep inside the respiratory region. A cross-sectional study was conducted to evaluate dust exposure risk at two Pt mine waste rock crusher plants (Facility A and B) in Limpopo, South Africa. Workers’ demographic and occupational information was collected through a structured questionnaire, a walk-through observation on facilities’ processes, and static dust sampling for the collection of inhalable and respirable dust particles using the National Institute for Occupational Safety and Health (NIOH) 7602 and the Methods for Determination of Hazardous Substance (MDHS) 14/4 as guidelines. Only 79% of Pt mine workers, used their respiratory protective equipment (RPE), sixty-five percent were exposed to work shifts exceeding the recommended eight hours and 8.8% had been employed for more than ten years. The mean time-weighted average (TWA) dust concentrations between Facility A and B showed a significant difference (p < 0.026). The Pt mine’s inhalable concentrations (range 0.03–2.2 mg/m3) were higher than the respirable concentrations (range 0.02–0.7 mg/m3), however were all below the respective international and local occupational exposure limits (OELs). The Pt mine’s respirable crystalline silica (SiO2) quartz levels were all found below the detectable limit (<0.01 mg/m3). The Pt miners had increased health risks due to accumulated low levels of dust exposure and lack of usage of RPE. It is recommended that an improved dust control program be put in place which includes, but is not limited to, stockpile enclosures, tire stops with water sprays, and education on the importance of RPE usage.

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Munker, Stefan, Martin Vogelhuber, Jan Bornschein, et al. "EpiCO (epirubicin, cyclophosphamide and vincristine) as treatment for extrapulmonary high-grade neuroendocrine neoplasms." Zeitschrift für Gastroenterologie 58, no. 02 (2020): 133–36. http://dx.doi.org/10.1055/a-1042-6504.

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AbstractHigh-grade neuroendocrine neoplasms (NEN) comprise a rare entity. Due to the lack of randomized controlled trials, therapy recommendations were mainly extrapolated from its pulmonary analogue, small cell lung cancer and mostly validated in small retrospective case series. The multicentric Nordic NEC Study of gastro-entero-pancreatic (GEP) and cancer of unknown primary (CUP) high-grade neuroendocrine neoplasms showed a significant disease control upon treatment with etoposide and platinum-based chemotherapies 1. Such a combination with etoposide and a platinum (CE) compound is currently considered standard first-line treatment for high-grade GEP/CUP NEN. High-grade mixed-neuroendocrine-non-neuroendocrine neoplasms (MiNEN) formerly termed mixed adeno-neuroendocrine carcinomas (MANEC) also have a poor prognosis and are generally treated like other high-grade NEN. The CE protocol has significant activity in high-grade NEN and MiNEN, but the response is short-lived in most cases with response rates around 50–60 %. Second-line treatment alternatives are not established so far. The need for additional treatment options is evident.Combination chemotherapy with doxorubicin, cyclophosphamide and vincristine (CAV) showed efficacy in small cell lung carcinoma (SCLC) and was considered standard first-line therapy before the era of etoposide and platinum combinations. Due to a better toxicity profile, doxorubicin was replaced by epirubicin, resulting in the combination of epirubicin, cyclophosphamide and vincristine (abbreviated as EpiCO or CEV).In analogy to SCLC, selected patients with high-grade NEN were treated with the EpiCO regimen in second line (or in one patient first line) at our center. In this report we present the retrospective series of 5 cases with metastatic high-grade GEP/CUP NEN/MiNEN who received chemotherapy according to this protocol.

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Novaes, Maristela Abadia Fernandes. "Villa Platina: urbanização e moda no sertão da Belle Époque." Ateliê Geográfico 12, no. 2 (2018): 78–97. http://dx.doi.org/10.5216/ag.v12i2.45644.

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Resumo Villa Platina, assim foi chamada de 1901 a 1915. Antes de 1901, era denominada Arraial de São José do Tijuco e, depois de 1915, passa à condição de cidade com o nome de Ituiutaba, Minas Gerais. O período em que se denominou Villa Platina coincide com o ápice da Belle Époque. A pesquisa se baseia nos pressupostos teóricos metodológicos estabelecidos por Fernand Braudel, em que se considera o contexto sociopolítico e econômico para o estudo da moda. O objetivo deste artigo é analisar um aspecto da sociedade platinense: o início do processo de urbanização de Ituiutaba e sua relação com a moda criada nos grandes centros europeus. A pesquisa se fundamenta em documentos oficiais da administração pública municipal e estadual, em jornais, em revistas de moda e na pesquisa bibliográfica. Palavras-chave: urbanização, moda, sertão, Minas Gerais, Belle Époque.  Abstract Villa Platina was named that way from 1901 to 1915. Before 1901 it was named Arraial de São José do Tijuco and after 1915 it became a city with the name of Ituiutaba, Minas Gerais. The period in which it was denominated Villa Platina maches with the apex period called Belle Époque. The research is based on theoretical methodological assumptions established by Fernand Braudel, in which the socio-political and economic context for the study of fashion is considered. The aim of this article is to analyse an aspect of Platinense society: the beginning of the urbanization process of Ituiutaba and its relation with this fashion created in great European centers. he research is based on official documents of the municipal and state public administration, on newspapers, on fashion magazines and on bibliographical research. Keywords: urbanization, fashion, sertão, Minas Gerais, Belle Époque.  Resumen Villa Platina, así fue llamada de 1901 a 1915. Antes de 1901, era llamada Arraial de São José do Tijuco, después de 1915, pasó a la condición de ciudad con el nombre de Ituiutaba, Minas Gerais. El periodo en que se denominó Villa Platina coincide con el ápice de Belle Époque. La investigación se basa en los presupuestos teóricos metodológicas establecidos por Fernand Braudel, en el que se considera el contexto sociopolítico y económico para el estudio de la moda. El objetivo de este artículo es analizar, un aspecto de la sociedad platinense: el inicio del proceso de urbanización de Ituiutaba y su relación con esa moda criada en los grandes centros europeos. La investigación se fundamenta en documentos oficiales de la administración pública municipal y estatal, en periódicos, en revistas de moda y en la investigación bibliográfica. Palabras-clave: urbanización, moda, sertão, Minas Gerais, Belle Époque.

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Bindi, L., F. Zaccarini, G. Garuti, and N. Angeli. "The solid solution between platinum and palladium in nature." Mineralogical Magazine 77, no. 3 (2013): 269–74. http://dx.doi.org/10.1180/minmag.2013.077.3.04.

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AbstractChemical and structural data are reported for platinum–palladium intermediates from two nuggets found at Córrego Bom Sucesso, Minas Gerais, Brazil. Three grains with simple stoichiometries (i.e. PtxPd1−x with x ∼0.67, ∼0.5 and ∼0.33, which correspond to Pt2Pd, PtPd and PtPd2, respectively) were characterized by single-crystal X-ray diffraction and electron-probe microanalysis. In the absence of single-crystal data it might be tempting to hypothesize that such simple stoichiometries represent distinct mineral species, however structural analyses show that all of the phases are cubic and crystallize in space group Fmm. They are, therefore, natural intermediates in the palladium–platinum solid solution. Reflectance and micro-hardness values are reported for the samples and a comparison with the pure metallic elements made. On the basis of information gained from the chemical and structural characterization it can be concluded that there is a complete solid solution between Pt and Pd in nature. These findings corroborate results from experiments on synthetic compounds.

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Cabral, A. R., G. Beaudoin, M. Choquette, B. Lehmann, and J. C. Polônia. "Supergene leaching and formation of platinum in alluvium: evidence from Serro, Minas Gerais, Brazil." Mineralogy and Petrology 90, no. 1-2 (2006): 141–50. http://dx.doi.org/10.1007/s00710-006-0171-3.

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Belkin, Harvey E., and Andrew E. Grosz. "Platinum and gold placer from Tugidak Island, Alaska: Platinum-group minerals and their inclusions, gold, and chromite mineralogy." Canadian Mineralogist 59, no. 4 (2021): 667–712. http://dx.doi.org/10.3749/canmin.2000016.

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ABSTRACT Black sand beach placers from Kodiak, Sitkinak, and Tugidak Islands, Alaska, have been mined intermittently for gold and minor platinum-group alloys for more than 100 years. High-grade platinum-rich magnetic separate and accompanying black sand from the southern beach placer of Tugidak Island were studied using electron microprobe WDS and scanning electron microscope EDS; mineral classification and identification were based on these techniques. The major platinum mineral is isoferroplatinum, followed by minor tetraferroplatinum and tulameenite, and rare ferronickelplatinum. Two types of alteration were identified in about 3–4% of the alloy grains: rim formation involving Pt loss and increased Fe, Ni, and/or Cu, and fracturing and vein filling by Cu-rich alloy. Ruthenium-Ir-Os-Pt alloys occur as inclusions and veins as well as form part of composite grains. Ten percent of the alloy grains contain a large variety of platinum-group minerals (PGM). Inclusions of cuprorhodsite, malanite, cuproiridsite, laurite, erlichmanite, cooperite, braggite, bowieite, kashinite, miassite, hollingworthite, irarsite, sperrylite, stillwaterite, genkinite, stibiopalladinite, keithconnite, zvyagintsevite, and probable palladodymite and vincentite were identified. Two unidentified inclusion phases also occur. Most of the PGM inclusions are primary and were trapped by a growing crystal from a melt; some inclusions exhibit textures that suggest trapping of an As,Te,S-rich immiscible melt. Secondary inclusions and evidence of deformation were observed in a few alloy grains. Associated with PGM inclusions or as separate inclusions are various base-metal sulfides. Two silicate-melt inclusions in one isoferroplatinum grain have an andesite–shoshonite composition. Minor gold and Ag-rich gold in the high-grade magnetic separate contain magnetite, pyrrhotite, and chromite inclusions. The gold composition suggests that their sources are the numerous quartz veins and apophyses related to granitoids on Kodiak Island. The composition of the placer chromite is similar to chromite from the Border Ranges mélange fault system and suggests that the Uyak Complex ultramafic and mafic rocks are part of a supra-subduction-zone ophiolite and are the source of the platinum-group minerals.

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Chalmers, Peggy. "Lobster Special." Mechanical Engineering 122, no. 09 (2000): 82–84. http://dx.doi.org/10.1115/1.2000-sep-5.

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This article reviews that Defense Advanced Research Projects Agency’s (DARPA) biomimetic programs is a robotic lobster that is under development at Northeastern University in Boston. This crustacean look-alike may someday ply river and sea bottoms, at depths to 40 feet, seeking underwater mines and other military prey. The robotic lobster will have to operate for hours, accommodate irregular rivers and sea beds, maneuver at various depths, adapt to rough and tumble surf, handle changing currents, distinguish between rocks and mines, and send out a sonar alert when it detects a mine. The sensors, which are the width of a human hair, are fabricated using an internally developed process called NUMEM (for Northeastern University Metal Micromachining), which builds up the devices through a sequence of metal deposition, patterning and selective etching, and plating on a silicon substrate. Signals from both the antenna and the hair sensors are processed in the lobster’s microprocessor brain and used to control the bionic leg muscles.

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Labuschagne, Marelize, Victor Wepener, Milen Nachev, Sonja Zimmermann, Bernd Sures, and Nico J. Smit. "The Application of Artificial Mussels in Conjunction with Transplanted Bivalves to Assess Elemental Exposure in a Platinum Mining Area." Water 12, no. 1 (2019): 32. http://dx.doi.org/10.3390/w12010032.

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There is increasing evidence that platinum group elements (PGE) are pollutants of emerging concern worldwide. Limited information exists on levels, particularly in regions where PGEs are mined. A passive sampling device (i.e., the artificial mussel (AM)) and transplanted indicator organisms (i.e., the freshwater clam Corbicula fluminalis africana) were deployed along a PGE mining gradient in the Hex River, South Africa, and concentrations of As, Cd, Co, Cr, Ni, Pb, Pt, V, and Zn were determined after six weeks of exposure. Results showed differential uptake patterns for Pt, Cr, and Ni between the AMs and clams indicating availability differences. For monitoring purposes, a combination of AMs and indicator organisms provides a more holistic assessment of element exposure in aquatic environments.

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Magaziner, Daniel, and Sean Jacobs. "Notes from Marikana, South Africa: The Platinum Miners’ Strike, the Massacre, and the Struggle for Equivalence." International Labor and Working-Class History 83 (2013): 137–42. http://dx.doi.org/10.1017/s0147547913000112.

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AbstractThis note reflects on the August 2012 miners' strike at Marikana, South Africa in light of a century long history of violence associated with worker actions in that country and elsewhere in the Global South. It suggests that the breakaway union's allegedly ‘illegal’ strike fits within a long tradition of radical worker activism in South Africa, which is best understood in light of anticolonial efforts to short-circuit the chronologies of imperial power. The Marikana strike, like anticolonial rebellions during the early twentieth century and, critically, white worker struggles following First World War, was an effort to speed up the process by which the value of workers’ lives and labor might be made equivalent to those in power.

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Dube, Gugulethu, and Brian Chanda Chiluba. "Burden of Silicosis in the South African Mining Sector and its Effects on Migrant Labor from Neighboring Countries." Journal of Preventive and Rehabilitative Medicine 3, no. 1 (2021): 20–25. http://dx.doi.org/10.21617/jprm2021.316.

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Background: Among other minerals, South Africa has an abundance of asbestos and crystalline silica. Due to dust particles from these minerals, exposure causes respiratory diseases in particular silicosis. Most researches on silicosis have largely been of a cross sectional nature with no or limited long-term patterns reported.Objective:This review aims to analyse silicosis patterns in the gold, diamond and platinum workers over a period of 30 years, and to investigate possible causative factors for mining sector employees leading to them developing respiratory diseases associated with silica.Methods:This review article is a product of analysis of published reports and studies from South Africa published in the last decades. The EliScholar digital platform and Google scholar were used, and the focus publications were those that related to “silicosis”, “migrant workers”, silica dust” and autopsy. The review also allowed articles that were generalized, not merely focusing on one mineral. Autopsy reports obtained from the National Institute for Occupational Health database on miners were used for three sub-studies that are the subject of this review.Conclusion:The silicosis trends in miners at autopsy show a clear system failure by the mining sector in controlling and managing occupational respiratory diseases

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Gridelli, Cesare, Alessandro Morabito, Luigi Cavanna, et al. "Cisplatin-Based First-Line Treatment of Elderly Patients With Advanced Non–Small-Cell Lung Cancer: Joint Analysis of MILES-3 and MILES-4 Phase III Trials." Journal of Clinical Oncology 36, no. 25 (2018): 2585–92. http://dx.doi.org/10.1200/jco.2017.76.8390.

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Purpose To test the efficacy of adding cisplatin to first-line treatment for elderly patients with advanced non–small-cell lung cancer (NSCLC) within a combined analysis of two parallel phase III trials, MILES-3 and MILES-4. Patients and Methods Patients with advanced NSCLC who were older than age 70 years with Eastern Cooperative Oncology Group performance status 0 to 1 were randomly assigned to gemcitabine or pemetrexed, without or with cisplatin. In each trial, 382 events were required to detect a hazard ratio (HR) of death of 0.75, with 80% power and two-tailed α of .05. Trials were closed prematurely because of slow accrual, but the joint database allowed us to analyze the efficacy of cisplatin on the basis of intention-to-treat and adjusted by trial, histotype, non-platinum companion drug, stage, performance status, sex, age, and size of the study center. Results From March 2011 to August 2016, 531 patients (MILES-3, 299; MILES-4, 232) were assigned to gemcitabine or pemetrexed without (n = 268) or with cisplatin (n = 263). Median age was 75 years, 79% were male, and 70% had nonsquamous histology. At a median 2-year follow-up, 384 deaths and 448 progression-free survival events were recorded. Overall survival was not significantly prolonged with cisplatin (HR, 0.86; 95% CI, 0.70 to 1.05; P = .14) and global health status score of quality of life was not improved, whereas progression-free survival (HR, 0.76; 95% CI, 0.63 to 0.92; P = .005) and objective response rate (15.5% v 8.5%; P = .02) were significantly better. Significantly more severe hematologic toxicity, fatigue, and anorexia were found with cisplatin. Conclusion The addition of cisplatin to single-agent chemotherapy does not significantly prolong overall survival, and it does not improve global health status score of quality of life in elderly patients with advanced NSCLC.

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Fleet, M. E., C. M. De Almeida, and N. Angeli. "BOTRYOIDAL PLATINUM, PALLADIUM AND POTARITE FROM THE BOM SUCESSO STREAM, MINAS GERAIS, BRAZIL: COMPOSITIONAL ZONING AND ORIGIN." Canadian Mineralogist 40, no. 2 (2002): 341–55. http://dx.doi.org/10.2113/gscanmin.40.2.341.

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Murciano-Goroff, Yonina R., Alison M. Schram, Ezra Rosen, et al. "BRCA reversion mutations in a pan-cancer cohort to reveal BRCA-dependence in select noncanonical BRCA-mutant histologies." Journal of Clinical Oncology 39, no. 15_suppl (2021): 3012. http://dx.doi.org/10.1200/jco.2021.39.15_suppl.3012.

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3012 Background: Loss of BRCA1/2 function leads to homologous recombination deficiency (HRD) and can enhance platinum and PARP inhibitor sensitivity in breast, pancreas, prostate, and ovarian cancers. In BRCA-associated cancers, resistance can result from the development of BRCA1/2 reversion mutations, which restore BRCA1/2 function. By contrast, a BRCA mutation may be an incidental finding in other tumor histologies. Methods: To determine the distribution of reversion mutations in a pan-cancer cohort, the MSK-IMPACT clinical sequencing cohort was mined to identify patients who had both a germline BRCA1/2 mutation and a frameshift somatic reversion mutation that restored BRCA1/2 function. Whole exome resequencing was used to detect HRD signatures. Chart review enabled collection of data on treatment history in patients consented to germline testing. Results: Of the 33,277 patients with matched tumor and normal sequencing profiled in this study, 861 patients were found to have germline pathogenic BRCA1/2 alterations, including 347 (40%) in BRCA1 and 514 (60%) in BRCA2. Somatic BRCA1/2 driver alterations were also found in tumor tissue from an additional 447 patients, with 156 (35%) having BRCA1 mutations, and the remainder having alterations in BRCA2 (65%) . Among the 1,308 germline or somatic BRCA1/2 mutant tumors, we identified reversion mutations in 12 patients, all of whom were germline carriers of BRCA1/2, comprising 3 BRCA1 and 9 BRCA2 tumors. 7 patients consented to germline testing enabling review of clinical characteristics and treatment history, 5 of whom received PARP inhibitor or platinum-therapy prior to reversion detection. Ten of 12 tumors with reversion mutations were in canonical BRCA-associated cancers. Interestingly, reversion mutations were also found in patients with lung adenocarcinoma (n=1) and gastroesophageal junction adenocarcinoma (n=1). In both these non-canonical histologies, the reversion was detected following progression on platinum-based therapy. Whole exome resequencing of the lung tumor revealed the classic somatic molecular phenotypes of HRD that are characteristic of BRCA-dependent tumors, including in terms of large-scale transitions, HRD-loss of heterozygosity, signature 3, and the number of telomeric allelic imbalance score. Conclusions: Matched tumor and normal sequencing from a large cohort of patients with diverse cancer histologies reveals that reversion mutations are found across BRCA-associated cancer types. In rare cases, reversion mutations in BRCA1/2 following platinum-based therapy may be indicative of prior BRCA-dependence in select non-canonical tumor histologies.

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CASTRICINI, ARIANE, LEANDRA OLIVEIRA SANTOS, ROSIRES DELIZA, EUGÊNIO FERREIRA COELHO, and MARIA GERALDA VILELA RODRIGUES. "CARACTERIZAÇÃO PÓS-COLHEITA E SENSORIAL DE GENÓTIPOS DE BANANEIRAS TIPO PRATA." Revista Brasileira de Fruticultura 37, no. 1 (2015): 27–37. http://dx.doi.org/10.1590/0100-2945-058/14.

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RESUMOO norte de Minas Gerais é grande produtor de banana ‘Prata-Anã’ irrigada, cultura altamente suscetível ao Mal-do-Panamá. O uso de genótipos resistentes é uma alternativa, mas os frutos devem apresentar características pós-colheita o mais próximo possível da ‘Prata-Anã’, para melhor aceitação pelos consumidores. O objetivo do trabalho foi caracterizar frutos em pós-colheita, identificar a preferência e a intenção de compra de diferentes genótipos de bananeira tipo Prata. Os genótipos Prata-Anã, BRS Platina e Fhia-18. foram caracterizados no ponto de colheita (verdes) e maduros (estádio seis de maturação), por avaliações químicas, físicas e sensoriais. Quando verde, ‘BRS Platina’ apresentou maior massa fresca e tamanho que ‘Fhia-18’ e ‘Prata-Anã’. ‘Fhia-18.’ teve a tonalidade verde da casca mais intensa que a dos demais genótipos. Madura, ‘BRS Platina’ foi mais firme, mas com a mesma resistência ao despencamento que ‘Fhia-18’ e superior à ‘Prata-Anã’. ‘Fhia-18’ apresentou cor da casca com amarelo mais clara e tão brilhante quanto da ‘Prata-Anã’, mas ‘BRS Platina’ teve a tonalidade de amarelo mais intensa. Bananas ‘Fhia-18’ foram mais ácidas, ‘BRS Platina’, com menor acidez titulável, e ‘Prata-Anã’, o maior teor de sólidos solúveis. Os genótipos Prata-Anã e BRS Platina tiveram maior preferência e intenção de compra pelos consumidores, sendo as bananas ‘Prata-Anã’ em dedos e ‘BRS Platina’ e ‘Fhia-18’ em dedos, buquê e penca, as mais preferidas. Entretanto, a maioria compraria bananas ‘Prata-Anã’ em buquê e ‘BRS Platina’ e ‘Fhia-18’ em penca. Enquanto verdes, os genótipos foram semelhantes à ‘Prata-Anã’, e maiores diferenças químicas e físicas ocorreram quando maduros.

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Lim, Megan S. C., Robert J. Dowdeswell, Jill Murray, Nigel Field, Judith R. Glynn, and Pam Sonnenberg. "The Impact of HIV, an Antiretroviral Programme and Tuberculosis on Mortality in South African Platinum Miners, 1992–2010." PLoS ONE 7, no. 6 (2012): e38598. http://dx.doi.org/10.1371/journal.pone.0038598.

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García-Cossio, Fabio, Heiler Cossio-Mosquera, Bertha Conto García, Vianney Sarria Palacios, and Luis Emilio Conto García. "Artisanal mining and the use of plant diversity." Revista Facultad Nacional de Agronomía 70, no. 2 (2017): 8213–23. http://dx.doi.org/10.15446/rfna.v70n2.64525.

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This essay presents the variety of vegetation which is utilized in traditional mining activities in the municipalities of Cértegui (Subdistricts of: Cértegui cabecera, La Toma y Recta Larga) and the Panamerican Union (Subdistricts of Animas, Agua Clara and Quiadó). The data is a product of an ethnographic investigation which selected 57 active traditional miners of the local population in the project’s area of influence to demonstrate a sample of the “Application of techniques and practices for cleaner production in gold and platinum mining in the department of Chocó”. These miners aided in recognizing, collecting, photographing, and identifying 78 species of vegetation used in activities associated with traditional mining such as: separation of metals (separating gold from jagua, settling the greasy gold and blackening the troughs), creating traditional tools (troughs, sifters, mining tools to store save and weigh gold) to work in different types of traditional mining (‘guaches’ or pits, mazamorreo or barequeo (gold-panning), hoyadero (underground mining), zambullidero (underwater mining), canalon (sluice box), agua corrida (streaming water), cuelgas (channels) and arrimadero), and confirming the affectivity by performing demonstrations of the separation of gold from jagua with mucilaginous strata of vegetation. Examples of this vegetation include: snakewood (Cecropia peltata), rhombus-leaved sida (Sida rhombifolia), Common Broom (Pavonia fruticosa), Shoeblackplant (Hibiscus rosa-sinensis), Balsa tree (Ochroma pyramidale) and Guácimo (Apeiba tibourbou).

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Ayres, Robert U., and Laura Talens Peiró. "Material efficiency: rare and critical metals." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 371, no. 1986 (2013): 20110563. http://dx.doi.org/10.1098/rsta.2011.0563.

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In the last few decades, progress in electronics, especially, has resulted in important new uses for a number of geologically rare metals, some of which were mere curiosities in the past. Most of them are not mined for their own sake (gold, the platinum group metals and the rare Earth elements are exceptions) but are found mainly in the ores of the major industrial metals, such as aluminium, copper, zinc and nickel. We call these major metals ‘attractors’ and the rare accompanying metals ‘hitch-hikers’. The key implication is that rising prices do not necessarily call forth greater output because that would normally require greater output of the attractor metal. We trace the geological relationships and the functional uses of these metals. Some of these metals appear to be irreplaceable in the sense that there are no known substitutes for them in their current functional uses. Recycling is going to be increasingly important, notwithstanding a number of barriers.

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Journal articles on the topic 'Platinum mines'

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