18 research outputs found

    Towards Increased Recovery of Critical Raw Materials from WEEE– evaluation of CRMs at a component level and pre-processing methods for interface optimisation with recovery processes

    Get PDF
    Increasing recovery of critical raw materials (CRMs) from waste electrical and electronic equipment (WEEE) is a strategic priority to mitigate supply risks. Today, CRM recovery rates are generally low, with increases requiring new recovery processes and interface optimisation with pre-processing to ensure appropriate material flows for efficient recovery are generated. Here, results from an industrial trial to increase CRM recovery from WEEE are presented to inform development of pre-processing strategies which generate such material flows. Au, Ag, Co, Ga, Mg, Nb, Ru, Pd, Ir, Y, Nd, Sb, Ta and W are identified with XRF in components of a range of WEEE samples including within individual printed circuit board (PCB) components. CRM distribution in PCBs is mapped by visual inspection with reference to this data. Cost-effective methods to disassemble WEEE; isolate CRM bearing components, and upgrade/concentrate CRMs are evaluated for industrial adoption. A guillotine is found most suitable for LCD disassembly and separation of Au edge-contacts from PCBs, while cryocracking is best for isolation of internal components of digital media devices. Thermal PCB disassembly with a solder bath for simultaneous SMD removal and subsequent sieving to sort SMDs thereby concentrating CRMs for recovery is a promising approach. Microwave ashing of PCBs to concentrate CRMs is promising although off-gas treatment would be required. Recovery potential of identified CRMs from material streams generated is found to be poor due to lack of suitable recovery infrastructure except for precious and platinum group metals in PCBs, but available pyrometallurgical recovery permanently dissipates other CRMs present

    Occurrence of carbapenemase-producing Klebsiella pneumoniae and Escherichia coli in the European survey of carbapenemase-producing Enterobacteriaceae (EuSCAPE): a prospective, multinational study

    Full text link

    Are Host Genetics the Predominant Determinant of Persistent Nasal Staphylococcus aureus Carriage in Humans?

    No full text
    Background. Staphylococcus aureus nasal carriage is influenced by multifactorial interactions which are difficult to study in open populations. Therefore, we concomitantly assessed the epidemiological, microbiological, and human-genetic carriage-related factors in a nearly closed population. Methods. In 2006 and 2008, we collected nasal S. aureus strains, human DNA, and epidemiological data from 154 adult Wayampi Amerindians living in an isolated village in the Amazonian forest. The genetics of the strains (multilocus sequence type, spa type, and toxin-content type), epidemiological risk factors, antibiotic exposure, and allelic polymorphism of human genes putatively involved in carriage of the persistent carriers were compared with those of other volunteers. Results. Overall carriage prevalence was 41.7% in 2006 and 57.8% in 2008, but the overall prevalence of persistent carriage was only 26%. The rare and phylogenetically distant multilocus sequence type ST1223 was present in 18.5% of the carriers in 2006 and 34.8% in 2008. No epidemiological factors or antibiotic exposure were significantly associated with persistent carriage, but single nucleotide polymorphism distribution in C-reactive proteins C2042T and C1184T and interleukin-4 C524T genes was significantly associated (P=.02, by global test). Conclusion. Host genetic factors appeared to be the predominant determinant for S. aureus persistent nasal carriage in humans

    Occurrence of carbapenemase-producing Klebsiella pneumoniae and Escherichia coli in the European survey of carbapenemase-producing Enterobacteriaceae (EuSCAPE): a prospective, multinational study

    No full text
    Background Gaps in the diagnostic capacity and heterogeneity of national surveillance and reporting standards in Europe make it difficult to contain carbapenemase-producing Enterobacteriaceae. We report the development of a consistent sampling framework and the results of the first structured survey on the occurrence of carbapenemase-producing Klebsiella pneumoniae and Escherichia coli in European hospitals. Methods National expert laboratories recruited hospitals with diagnostic capacities, who collected the first ten carbapenem non-susceptible clinical isolates of K pneumoniae or E coli and ten susceptible same-species comparator isolates and pertinent patient and hospital information. Isolates and data were relayed back to national expert laboratories, which made laboratory-substantiated information available for central analysis. Findings Between Nov 1, 2013, and April 30, 2014, 455 sentinel hospitals in 36 countries submitted 2703 clinical isolates (2301 [85%] Kpneurnoniae and 402 (15%) Ecoli). 850 (37%) of 2301 Kpneumoniae samples and 77 (19%) of 402 Ecoli samples were carbapenemase (KPC, NDM, OXA-48-like, or VIM) producers. The ratio of K pneumoniae to E coli was 11:1.1.3 patients per 10000 hospital admissions had positive clinical specimens. Prevalence differed greatly, with the highest rates in Mediterranean and Balkan countries. Carbapenemase-producing K pneumoniae isolates showed high resistance to last-line antibiotics. Interpretation This initiative shows an encouraging commitment by all participants, and suggests that challenges in the establishment of a continent-wide enhanced sentinel surveillance for carbapenemase-producing Entero-bacteriaeceae can be overcome. Strengthening infection control efforts in hospitals is crucial for controlling spread through local and national health care networks
    corecore