In the life cycle assessment (LCA) of products, the increasing scarcity of metal resources is currently addressed in a preliminary way. Here, we propose a new method on the basis of global ore grade information to assess the importance of the extraction of metal resources in the life cycle of products. It is shown how characterization factors, reflecting the decrease in ore grade due to an increase in metal extraction, can be derived from cumulative ore grade-tonnage relationships. CFs were derived for three different types of copper deposits (porphyry, sediment-hosted, and volcanogenic massive sulfide). We tested the influence of the CF model (marginal vs average), mathematical distribution (loglogistic vs loglinear), and reserve estimate (ultimate reserve vs reserve base). For the marginal CFs, the statistical distribution choice and the estimate of the copper reserves introduce a difference of a factor of 1.0-5.0 and a factor of 1.2-1.7, respectively. For the average CFs, the differences are larger for these two choices, i.e. respectively a factor of 5.7-43 and a factor of 2.1-3.8. Comparing the marginal CFs with the average CFs, the differences are higher (a factor 1.7-94). This paper demonstrates that cumulative grade-tonnage relationships for metal extraction can be used in LCA to assess the relative importance of metal extractions.
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N Engl J Med
January 2025
From Médecins Sans Frontières (L.G., F.V.), Sorbonne Université, INSERM Unité 1135, Centre d'Immunologie et des Maladies Infectieuses (L.G.), Assistance Publique-Hôpitaux de Paris, Groupe Hospitalier Universitaire Sorbonne Université, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (L.G.), and Epicentre (M.G., E. Baudin), Paris, and Translational Research on HIV and Endemic and Emerging Infectious Diseases, Montpellier Université de Montpellier, Montpellier, Institut de Recherche pour le Développement, Montpellier, INSERM, Montpellier (M.B.) - all in France; Interactive Development and Research, Singapore (U.K.); McGill University, Epidemiology, Biostatistics, and Occupational Health, Montreal (U.K.); UCSF Center for Tuberculosis (G.E.V., P.N., P.P.J.P.) and the Division of HIV, Infectious Diseases, and Global Medicine (G.E.V.), University of California at San Francisco, San Francisco; the National Scientific Center of Phthisiopulmonology (A.A., E. Berikova) and the Center of Phthisiopulmonology of Almaty Health Department (A.K.), Almaty, and the City Center of Phthisiopulmonology, Astana (Z.D.) - all in Kazakhstan; Médecins Sans Frontières (C.B., I.M.), the Medical Research Council Clinical Trials Unit at University College London (I.M.), and St. George's University of London Institute for Infection and Immunity (S.W.) - all in London; MedStar Health Research Institute, Washington, DC (M.C.); Médecins Sans Frontières, Mumbai (V. Chavan), the Indian Council of Medical Research Headquarters-New Delhi, New Delhi (S. Panda), and the Indian Council of Medical Research-National AIDS Research Institute, Pune (S. Patil) - all in India; the Centre for Infectious Disease Epidemiology and Research (V. Cox) and the Department of Medicine (H. McIlleron), University of Cape Town, and the Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine (S.W.) - both in Cape Town, South Africa; the Institute of Tropical Medicine, Antwerp, Belgium (B. C. J.); Médecins Sans Frontières, Geneva (G.F., N.L.); Médecins Sans Frontières, Yerevan, Armenia (O.K.); the National Center for Tuberculosis and Lung Diseases, Tbilisi, Georgia (N.K.); Partners In Health (M.K.) and Jhpiego Lesotho (L.O.) - both in Maseru; Socios En Salud Sucursal Peru (L.L., S.M.-T., J.R., E.S.-G., D.E.V.-V.), Hospital Nacional Sergio E. Bernales, Centro de Investigacion en Enfermedades Neumologicas (E.S.-G.), Hospital Nacional Dos de Mayo (E.T.), Universidad Nacional Mayor de San Marcos (E.T.), and Hospital Nacional Hipólito Unanue (D.E.V.-V.) - all in Lima; Global Health and Social Medicine, Harvard Medical School (L.L., K.J.S., M.L.R., C.D.M.), Partners In Health (L.L., K.J.S., M.L.R., C.D.M.), the Division of Global Health Equity, Brigham and Women's Hospital (K.J.S., M.L.R., C.D.M.), the Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, (L.T.), and Harvard T.H. Chan School of Public Health (L.T.) - all in Boston; and the Indus Hospital and Health Network, Karachi, Pakistan (H. Mushtaque, N.S.).
Background: For decades, poor treatment options and low-quality evidence plagued care for patients with rifampin-resistant tuberculosis. The advent of new drugs to treat tuberculosis and enhanced funding now permit randomized, controlled trials of shortened-duration, all-oral treatments for rifampin-resistant tuberculosis.
Methods: We conducted a phase 3, multinational, open-label, randomized, controlled noninferiority trial to compare standard therapy for treatment of fluoroquinolone-susceptible, rifampin-resistant tuberculosis with five 9-month oral regimens that included various combinations of bedaquiline (B), delamanid (D), linezolid (L), levofloxacin (Lfx) or moxifloxacin (M), clofazimine (C), and pyrazinamide (Z).
Sci Rep
January 2025
Department of Fuel, Minerals and Metallurgical Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, India.
The Malanjkhand chalcopyrite deposit, India's primary copper ore producer, has potential for enhanced flotation performance. This study employs standard flotation experiments using a mechanical cell, integrating a conventional collecting agent with a novel ester-based collector blend. A three-factor, three-level Box-Behnken design systematically evaluated experimental parameters, analysed using ANOVA, cubic plots, response surface methodologies.
View Article and Find Full Text PDFACS Omega
December 2024
School of Minerals Processing and Bioengineering, Central South University, Changsha 410083, China.
As natural resources continue to be exploited, dense medium cyclones (DMCs) are increasingly utilized for the preconcentration of low-grade ores to meet the demands for higher feed grade, increased processing capacity, and reduced energy consumption. However, determining the optimal fineness of ferrosilicon remains ambiguous for different types of ores and is often described as more of an art than a science. This paper investigates the subtle effects of ferrosilicon fineness on flow field characteristics, medium classification, and the ore separation process using a validated numerical approach, which integrates a two-fluid model, a turbulence dispersion model, and a discrete phase model.
View Article and Find Full Text PDFPolymers (Basel)
November 2024
Center of Physical Chemical Methods of Research and Analysis, Faculty of Chemistry and Chemical Technology, Al-Farabi Kazakh National University, Al-Farabi Ave. 71, Almaty 050038, Kazakhstan.
Chemosphere
February 2025
College of Health and Science, School of Natural Science, University of Lincoln, Joseph Banks Laboratories, Green Lane, Lincoln, Lincolnshire, LN6 7DL, United Kingdom. Electronic address:
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