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1.
Sci Data ; 10(1): 391, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37339978

RESUMO

Given that metals, minerals and energy resources extracted through mining are fundamental to human society, it follows that accurate data describing mine production are equally important. Although there are often national statistical sources, this typically includes data for metals (e.g., gold), minerals (e.g., iron ore) or energy resources (e.g., coal). No such study has ever compiled a national mine production data set which includes basic mining data such as ore processed, grades, extracted products (e.g., metals, concentrates, saleable ore) and waste rock. These data are crucial for geological assessments of mineable resources, environmental impacts, material flows (including losses during mining, smelting-refining, use and disposal or recycling) as well as facilitating more quantitative assessments of critical mineral potential (including possible extraction from tailings and/or waste rock left by mining). This data set achieves these needs for Australia, providing a world-first and comprehensive review of a national mining industry and an exemplar of what can be achieved for other countries with mining industry sectors.


Assuntos
Conjuntos de Dados como Assunto , Metais , Minerais , Mineração , Austrália , Monitoramento Ambiental , Ouro/normas , Ouro/provisão & distribuição , Metais/normas , Metais/provisão & distribuição , Minerais/normas , Minerais/provisão & distribuição , Mineração/estatística & dados numéricos , Reciclagem
2.
J Cardiovasc Electrophysiol ; 18(7): 709-13, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17537205

RESUMO

INTRODUCTION: Radiofrequency (RF) ablation of the cavotricuspid isthmus (CTI) can be performed using different types of ablation catheter. Gold tip electrodes have the theoretical advantage of creating bigger lesions than standard platinum-iridium electrode. This prospective, randomized study compares the clinical efficacy of 8-mm gold tip catheter, externally irrigated and 8-mm platinum-iridium tip (Pt tip) catheters. METHODS AND RESULTS: Sixty consecutive patients (51 men, 60 +/- 10 years) undergoing de novo CTI ablation for documented typical atrial flutter were randomized to one of the following ablation catheters: 8-mm gold tip catheter, an externally irrigated-tip (Irr. tip) catheter, or an 8-mm Pt tip catheter. The procedural endpoint was achievement of bidirectional isthmus conduction block with < or = 20 minutes of RF energy application. The latter was achieved equally with the 3 catheters (95% for gold tip, 100% for irrigated tip, 95% for Pt tip) and the durations of RF (10 +/- 6, 10 +/- 4, 13 +/- 8 minutes), fluoroscopy (12 +/- 6, 12 +/- 7, 15 +/- 12 minutes) and the procedure (34 +/- 23, 38 +/- 24, 40 +/- 30 minutes) were similar in all groups. The maximal targeted power could not be reached in at least one location in 40% of patients with gold tip and in 35% of patients with Pt tip catheters whereas it was always achieved with an Irr. tip catheter (P = 0.003, P = 0.008). The reduction in impedance during RF delivery was greater with Irr. tip (11 +/- 7 ohms) than with gold (7 +/- 4 ohms, P = 0.02) or Pt tip (5 +/- 3 ohms, P = 0.001) catheters. CONCLUSION: This study demonstrates equivalent efficacies of gold, platinum-iridium and externally Irr. tip catheters for successful de novo ablation of the CTI.


Assuntos
Ablação por Cateter/instrumentação , Ouro , Irídio , Platina , Valva Tricúspide/cirurgia , Idoso , Flutter Atrial/patologia , Flutter Atrial/cirurgia , Ablação por Cateter/métodos , Cateterismo/normas , Feminino , Seguimentos , Ouro/normas , Humanos , Irídio/normas , Masculino , Pessoa de Meia-Idade , Platina/normas , Estudos Prospectivos , Valva Tricúspide/patologia
3.
J Neurosci Methods ; 155(1): 72-6, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16466802

RESUMO

The rat electrical kindling model has been widely utilized in epilepsy research. This study aimed to identify the optimum "MRI compatible" bipolar stimulating and recording electrodes to enable serial MRI acquisition in this model. Two types of custom-made electrodes (gold and carbon) were compared with commercial platinum-iridium alloy electrodes for suitability based on size, effect on image quality and kindling induction. The custom-made gold electrodes, based on these parameters, were found to be most suitable. These electrodes enable the study of epileptogenesis utilizing MRI in this model of temporal lobe epilepsy (TLE).


Assuntos
Tonsila do Cerebelo/fisiopatologia , Eletroencefalografia/instrumentação , Epilepsia/fisiopatologia , Excitação Neurológica/fisiologia , Imageamento por Ressonância Magnética/métodos , Neurofisiologia/instrumentação , Tonsila do Cerebelo/patologia , Animais , Carbono/normas , Modelos Animais de Doenças , Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos , Eletrodos Implantados/normas , Eletrodos Implantados/tendências , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Ouro/normas , Irídio/normas , Imageamento por Ressonância Magnética/normas , Masculino , Neurofisiologia/métodos , Platina/normas , Ratos , Ratos Wistar
4.
Adv Space Res ; 12(2-3): 461-4, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-11537045

RESUMO

The Shuttle Activation Monitor (SAM) experiment was flown on the Space Shuttle Columbia (STS-28) from 8-13 August, 1989 in a 57 degrees, 300 km orbit. One objective of the SAM experiment was to determine the relative effect of different amounts of shielding on the gamma-ray backgrounds measured with similarly configured sodium iodide (NaI) and bismuth germante (BGO) detectors. To achieve this objective twenty-four hours of data were taken with each detector in the middeck of the Shuttle on the ceiling of the airlock (a high-shielding location) as well as on the sleep station wall (a low-shielding location). For the cosmic-ray induced background the results indicate an increased overall count rate in the 0.2 to 10 MeV energy range at the more highly shielded location, while in regions of trapped radiation the low shielding configuration gives higher rates at the low energy end of the spectrum.


Assuntos
Radiação Cósmica , Raios gama , Monitoramento de Radiação/normas , Proteção Radiológica/normas , Voo Espacial , Astronave/normas , Alumínio/normas , Bismuto , Ouro/normas , Níquel/normas , Prótons , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Proteção Radiológica/instrumentação , Proteção Radiológica/métodos , Iodeto de Sódio , Astronave/instrumentação , Dosimetria Termoluminescente
5.
Arthritis Rheum ; 33(10): 1449-61, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1977391

RESUMO

We performed 2 metaanalyses of placebo-controlled and comparative clinical trials to examine the relative efficacy and toxicity of methotrexate (MTX), injectable gold, D-penicillamine (DP), sulfasalazine (SSZ), auranofin (AUR), and antimalarial drugs, the second-line drugs most commonly used to treat rheumatoid arthritis (RA). For the efficacy study, we applied a set of inclusion criteria and focused on trials which provided information on tender joint count, erythrocyte sedimentation rate, or grip strength. We found 66 clinical trials that contained 117 treatment groups of interest, and for each drug, we combined the treatment groups. For each outcome, results showed that AUR tended to be weaker than other second-line drugs. The results of the 3 outcome measures were synthesized into a composite measure of outcomes, and AUR was significantly weaker than MTX (P = 0.006), injectable gold (P less than 0.0001), DP (P less than 0.0001), and SSZ (P = 0.009) and was slightly, but not significantly, weaker than antimalarial agents (P = 0.11). We also found heterogeneity among antimalarial agents, in that patients treated with chloroquine did better than those treated with hydroxychloroquine. We found little difference in efficacy between MTX, injectable gold, DP, and SSZ. A power analysis showed that a trial should contain at least 170 patients per treatment group to successfully differentiate between more effective and less effective (e.g., AUR) second-line drugs. None of the reported interdrug comparative trials we reviewed were this large. For the toxicity study, our inclusion criteria captured RA trials which reported the proportion of patients who discontinued therapy because of drug toxicity and the total proportion who dropped out. We found 71 clinical trials that contained 129 treatment groups. The average proportion who dropped out and the average proportion who dropped out because of drug toxicity were computed for each drug. Overall, 30.2% of the patients in these trials dropped out; 50% of them did so because of drug toxicity. Injectable gold had higher toxicity rates (P less than 0.05) and higher total dropout rates (P less than 0.01) than any other drug; 30% of gold-treated patients dropped out because of side effects versus 15% of all trial patients. Antimalarial drugs and AUR had relatively low rates of toxicity; the rate for MTX was imprecise because of discrepancies between trials. Thus, of the commonly used second-line drugs, AUR is the weakest, and injectable gold is the most toxic. Agents introduced in the future will be compared with these drugs.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Antimaláricos/normas , Artrite Reumatoide/tratamento farmacológico , Auranofina/normas , Antimaláricos/toxicidade , Auranofina/toxicidade , Ouro/normas , Ouro/toxicidade , Humanos , Metanálise como Assunto , Metotrexato/normas , Metotrexato/toxicidade , Penicilamina/normas , Penicilamina/toxicidade , Sulfassalazina/normas , Sulfassalazina/toxicidade
14.
J Am Acad Gold Foil Oper ; 13(1): 17-22, 1970 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-5267297
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