482 research outputs found

    Selective formation of copper nanoparticles from acid mine drainage using nanoscale zerovalent iron particles

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    Nanoscale zerovalent iron (nZVI) has been investigated for the selective formation of Cu nanoparticles from acid mine drainage (AMD) taken from a legacy mine site in the UK. Batch experiments were conducted containing unbuffered (pH 2.67 at t=0) and pH buffered (pH 99.9% removal of all metals within 1 h when nZVI ≥1.0 g/L) from unbuffered AMD despite the coexistent of numerous other metals in the AMD, namely: Na, Ca, Mg, K, Mn and Zn. An acidic pH buffer enabled similarly high Cu removal but maximum removal of only <1.5% and <0.5% Cd and Al respectively. HRTEM-EDS confirmed the formation of discrete spherical nanoparticles comprised of up to 68% wt. Cu, with a relatively narrow size distribution (typically 20-100 nm diameter). XPS confirmed such nanoparticles as containing Cu0 , with the Cu removal mechanism therefore likely via cementation with Fe0 . Overall the results demonstrate nZVI as effective for the one-pot and selective formation of Cu0 -bearing nanoparticles from acidic wastewater, with the technique therefore potentially highly useful for the selective upcycling of dissolved Cu in wastewater into high value nanomaterials

    Towards 'Precision Mining' of wastewater: Selective recovery of Cu from acid mine drainage onto diatomite supported nanoscale zerovalent iron particles

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    This paper introduces the concept of ‘Precision Mining’ of metals which can be defined as a process for the selective in situ uptake of a metal from a material or media, with subsequent retrieval and recovery of the target metal. In order to demonstrate this concept nanoscale zerovalent iron (nZVI) was loaded onto diatomaceous earth (DE) and tested for the selective uptake of Cu from acid mine drainage (AMD) and subsequent release. Batch experiments were conducted using the AMD and nZVI-DE at 4.0–16.0 g/L. Results demonstrate nZVI-DE as highly selective for Cu removal with >99% uptake recorded after 0.25 h when using nZVI-DE concentrations ≥12.0 g/L, despite appreciable concentrations of numerous other metals in the AMD, namely: Co, Ni, Mn and Zn. Cu uptake was maintained in excess of 4 and 24 h when using nZVI-DE concentrations of 12.0 and 16.0 g/L respectively. Near-total Cu release from the nZVI-DE was then recorded and attributed to the depletion of the nZVI component and the subsequent Eh, DO and pH recovery. This novel Cu uptake and release mechanism, once appropriately engineered, holds great promise as a novel ‘Precision Mining’ process for the rapid and selective Cu recovery from acidic wastewater, process effluents and leach liquors

    Cp*Fe(Me2PCH2CH2PMe2)(CHO) : hydride shuttle reactivity of a thermally stable formyl complex.

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    [Cp*Fe(Me2PCH2CH2PMe2)(CO)]+ [BArF24]− has been synthesised and characterised using single crystal X-ray diffraction, NMR and IR spectroscopies. Reduction of the CO ligand using Na[Et3BH] produces the corresponding neutral formyl complex Cp*Fe(Me2PCH2CH2PMe2)(CHO), that is very thermally stable, and which is attributed to the electron-releasing properties of the spectator ligands. This compound is a potent hydride donor which exists in equilibrium with [Et3BH]−, Et3B, and the structural isomer (η4-C5Me5H)Cp*Fe(Me2PCH2CH2PMe2)(CO), resulting from reversible hydride migration to the Cp* ligand

    Infection-Related Hospitalization in Heart Failure With Reduced Ejection Fraction: A Prospective Observational Cohort Study

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    Background: Hospitalization is a common adverse event in people with heart failure and reduced ejection fraction, yet is often not primarily due to decompensated heart failure (HF). We investigated the long-term prognosis following infection-related hospitalization. Methods: We conducted a prospective observational cohort study of 711 people with heart failure and reduced ejection fraction recruited from 4 specialist HF clinics in the United Kingdom. All hospitalization episodes (n=1568) were recorded and categorized as primarily due to decompensated HF, other cardiovascular disease, infection-related, or other noncardiovascular disease. Survival was determined after the first hospitalization. Results: During 2900 patient-years of follow-up, there were a total of 14 686 hospital days. At least one hospitalization occurred in 467 people (66%); 25% of first hospitalizations were primarily due to infection and these were not associated with typical signs including tachycardia and pyrexia. Compared with other categories of hospitalization, infection-related was associated with older age, lower serum albumin, higher blood neutrophil counts, and greater prevalence of chronic obstructive pulmonary disease at recruitment. Median survival after first infection-related hospitalization was 18.6 months, comparable to that after first decompensated HF hospitalization, even after age-sex adjustment. The burden of all-cause rehospitalization was comparable irrespective of the category of first hospitalization, but infection more commonly caused re-hospitalization after index infection hospitalization. Conclusions: Infection is a common driver of hospitalization in heart failure and reduced ejection fraction and often presents without classical signs. It is associated with high mortality rates, comparable to decompensated HF, and a major burden of rehospitalization caused by recurrent episodes of infection

    Omicron variant infection in inflammatory rheumatological conditions – outcomes from a COVID-19 naive population in Aotearoa New Zealand

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    Background: Due to geographic isolation and border controls Aotearoa New Zealand (AoNZ) attained high levels of population coronavirus disease-19 (COVID-19) vaccination before widespread transmission of COVID-19. We describe outcomes of SARS-CoV-2 infection (Omicron variant) in people with inflammatory rheumatic diseases in this unique setting. Methods: This observational study included people with inflammatory rheumatic disease and SARS-CoV-2 infection in AoNZ between 1 February and 30 April 2022. Data were collected via the Global Rheumatology Alliance Registry including demographic and rheumatic disease characteristics, and COVID-19 vaccination status and outcomes. Multivariable logistic regression was used to explore associations of demographic and clinical factors with COVID-19 hospitalisation and death. Findings: Of the 1599 cases included, 96% were from three hospitals that systematically identified people with inflammatory rheumatic disease and COVID-19. At time of COVID-19, 1513 cases (94.6%) had received at least two COVID-19 vaccinations. Hospitalisation occurred for 104 (6.5%) cases and 10 (0.6%) patients died. Lower frequency of hospitalisation was seen in cases who had received at least two vaccinations (5.9%), compared to the unvaccinated (20.6%) or those with a single vaccine dose (10.7%). In multivariable adjusted models, people with gout or connective tissue diseases (CTD) had increased risk of the combined outcome of hospitalisation/death, compared to people with inflammatory arthritis. Glucocorticoid and rituximab use were associated with increased rates of hospitalisation/death. All patients who died had three or more co-morbidities or were over 60 years old. Interpretation: In this cohort with inflammatory rheumatic diseases and high vaccination rates, severe outcomes from SARS-CoV-2 Omicron variant were relatively infrequent. The outcome of Omicron variant infection among vaccinated but SARS-CoV-2 infection-naive people with inflammatory rheumatic disease without other known risk factors were favourable. Funding: Financial support from the American College of Rheumatology (ACR) and European Alliance of Associations for Rheumatology (EULAR) included management of COVID-19 Global Rheumatology Alliance funds

    Male Imprisoned Firesetters Have Different Characteristics than Other Imprisoned Offenders and Require Specialist Treatment

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    Objective: This study investigated whether a group of firesetters (n = 68) could be distinguished, psychologically, from a matched group of non-firesetting offenders (n = 68). Method: Participants completed measures examining psychological variables relating to fire, emotional/ self-regulation, social competency, self-concept, boredom proneness, and impression management. Official prison records were also examined to record offending history and other offense-related variables. A series of MANOVAs were conducted with conceptually related measures identified as the dependent variables. Follow up discriminant function and clinical cut-off score analyses were also conducted to examine the best discriminating variables for firesetters. Results: Firesetters were clearly distinguishable, statistically, from non-firesetters on three groups of conceptually related measures relating to: fire, emotional/self-regulation, and self-concept. The most successful variables for the discrimination of firesetters determined via statistical and clinical significance testing were higher levels of anger-related cognition, interest in serious fires, and identification with fire and lower levels of perceived fire safety awareness, general self-esteem, and external locus of control. Conclusions: Firesetters appear to be a specialist group of offenders who hold unique psychological characteristics. Firesetters are likely to require specialist treatment to target these psychological needs as opposed to generic offending behavior programs

    Mechanisms of Size Control and Polymorphism in Viral Capsid Assembly

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    We simulate the assembly dynamics of icosahedral capsids from subunits that interconvert between different conformations (or quasi-equivalent states). The simulations identify mechanisms by which subunits form empty capsids with only one morphology but adaptively assemble into different icosahedral morphologies around nanoparticle cargoes with varying sizes, as seen in recent experiments with brome mosaic virus (BMV) capsid proteins. Adaptive cargo encapsidation requires moderate cargo-subunit interaction strengths; stronger interactions frustrate assembly by stabilizing intermediates with incommensurate curvature. We compare simulation results to experiments with cowpea chlorotic mottle virus empty capsids and BMV capsids assembled on functionalized nanoparticles and suggest new cargo encapsidation experiments. Finally, we find that both empty and templated capsids maintain the precise spatial ordering of subunit conformations seen in the crystal structure even if interactions that preserve this arrangement are favored by as little as the thermal energy, consistent with experimental observations that different subunit conformations are highly similar

    Screening for psychological distress in patients with lung cancer: results of a clinical audit evaluating the use of the patient Distress Thermometer

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    Patients with lung cancer frequently suffer psychological distress and guidelines in the United Kingdom recommend screening of all cancer patients for this problem. The audit investigated use of the Distress Thermometer in terms of staff adherence to locally developed guidelines, patient willingness to use the tool, its impact on referral rates to clinical psychology services and concordance between the tool and the clinical assessment. Use of the Distress Thermometer was audited over a 3-month period in one lung cancer outpatient clinic. Referrals to clinical psychology services in response to clearly delineated referral indicators were assessed. Patient-reported outcomes were compared with practitioner assessment of need during clinical consultations to see whether the tool was measuring distress effectively. Thirty three of 34 patients used the Distress Thermometer during the audit period. Ten reported distress levels above 4 in the emotional or family problems domains. On ten occasions, the clinical interview identified problems not elicited by the Distress Thermometer. Guidelines were adhered to by staff, and patients were offered information about local support services and referral to clinical psychology services where indicated. Whilst all patients were happy to receive written information about further sources of support, none wanted to be referred to psychological services at that time. The Distress Thermometer is acceptable to patients with lung cancer in outpatient settings but it did not increase referrals for psychological support. Staff found it to be a useful tool in opening up communication about patient issues although it should not replace a comprehensive clinical interview
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