Objectives: The dissemination of Escherichia coli–producing extended-spectrum β-lactamase (ESBL-Ec) is evident in the community. In this population-based spatial analysis, we sought to describe the distribution of ESBL-Ec and to identify predictors of incidence in the community. Methods: The study population was defined as individuals with the ESBL-Ec isolate in Queensland, Australia, from 2010 to 2019. Annual choropleth maps and a global Moran index were constructed to describe ESBL-Ec distribution. Getis-Ord Gi* was performed to identify “hot spots” of statistical significance. Using demographic factors and incidence per postal area from 2016, multivariable analyses with or without spatially structured random effects were performed. Results: In total, 12,786 individuals with ESBL-Ec isolate were identified. The incidence rate increased annually from 9.1 per 100,000 residents in 2010 to 49.8 per 100,000 residents in 2019. The geographical distribution changed from random to clustered in 2014. Hot spots were more frequently identified in the Outback and Far North Queensland, where remote communities and hotter weather are prevalent. Multivariable spatial analysis suggests that communities with higher socioeconomic status (RR, 0.66; 95% CI, 0.55–0.79 per 100 units) and employment in the agricultural industry (RR, 0.79; 95% CI, 0.67–0.95 per 10%) were protective of lower ESBL-Ec incidence. After accounting for multiple demographic factors, the residual, structured, random-effects model indicated that hot spots were still detected in more remote communities but also in several city regions. Conclusions: The change in distribution of ESBL-Ec across Queensland suggests the presence of area-level specific risk factors that enhance spread in the community. Risk factors for spread appear different between remote and city settings, and future research should be tailored to understand the respective area-level risk factors. Factors such as local temperature, antibiotic consumption, and access to services should be validated. Future public health measures to reduce transmission should be focused on the identified hot spots.

The dissemination of Escherichia coli producing extended-spectrum beta-lactamase (ESBL-Ec) is evident in the community. A population-based spatial analysis is necessary to investigate community risk factors for ESBL-Ec occurrence. The study population was defined as individuals with ESBL-Ec isolated in Queensland, Australia, from 2010 to 2019. Choropleth maps, global Moran's index and Getis-Ord Gi* were used to describe ESBL-Ec distribution and identify hot spots. Multivariable Poisson regression models with or without spatially structured random effects were performed. A total of 12 786 individuals with ESBL-Ec isolate were identified. The crude incidence rate increased annually from 9.1 per 100 000 residents in 2010 to 49.8 per 100 000 residents in 2019. The geographical distribution of ESBL-Ec changed from random to clustered after 2014, suggesting presence of community-specific factors that can enhance occurrence. Hot spots were more frequently identified in Outback and Far North Queensland, future public health measures to reduce transmission should prioritise these communities. Communities with higher socioeconomic status (RR = 0.66, 95% CI 0.55–0.79, per 100 units increase) and higher proportion of residents employed in the agricultural industry (RR = 0.79, 95% CI 0.67–0.95, per 10% increase) had lower ESBL-Ec incidence. Risk factors for occurrence appear differential between remote and city settings and this should be further investigated.

The rare Li-mica taeniolite is described from the Dicker Willem carbonatite complex, Namibia, and from the Alpine carbonatitic lamprophyre dyke swarm at Haast River, New Zealand. At Haast River, taeniolite occurs in sodic and ultrasodic fenites derived from quartzo-feldspathic schists and rarely in metabasites, adjacent to dykes of tinguaite, trachyte and a spectrum of carbonatites ranging from Ca- to Fe- rich types. In Namibia, taeniolite is present in potassic fenites derived from quartz-feldspathic gneisses and granitoids at the margin of an early sövite phase of the complex and in a radial sövite dyke emanating from this centre.

The occurrence of taeniolite in these totally disparate carbonatite complexes, together with examples of lithian mica from other carbonatite complexes worldwide, raises the question of the status of Li as a ‘carbonatitic element’. We argue that lithium is not a consequence of crustal assimilation or interaction, but reflects the geochemical character of the magmatic source. Li, an overlooked and little-analysed element, may be an integral part of metasomatic enrichment in the mantle, and of magmas derived by partial melting of such a source.

A continuous-flow system was designed for the culture of aquatic weeds in the laboratory and used to examine the effects of low concentrations of terbutryn [N-(1,1-dimethylethyl)-N′-ethyl-6-(methylthio)-1,3,5-triazine-2,4-diamine] and diquat cation (6,7-dihydrodipyrido [1,2-:2′,1′-c] pyrazinediium ion) on algae (epiphyton) growing on surfaces of common elodea (Elodea canadensis L. C. Rich # ELDCA). Terbutryn did not affect the density of the epiphytic algal community, although development of the diatom component was favored at the highest concentration (50 μg/L). Diquat cation stimulated the growth of the epiphyton, particularly the diatoms, at concentrations as low as 5 μg/L. Possible reasons for this response included hormesis, differential tolerance to diquat, and facultative heterotrophy.

Antibiotic resistance is a major risk to human health, and to provide valuable insights into mechanisms of resistance, innovative methods are needed to examine the cellular responses to antibiotic treatment. Focused ion beam tomography is proposed to image and assess the detailed three-dimensional (3D) ultrastructure of single bacterial cells. By iteratively removing slices of thickness in the order of 10 nm, high magnification 2D images can be acquired by scanning electron microscopy at single-digit nanometer resolution. In this study, Klebsiella pneumoniae was treated with polymyxin B, and 3D models of both cell envelope and cytoplasm regions containing the nucleoid and ribosomes were reconstructed. The 3D volume containing the nucleoid and ribosomes was significantly smaller, and the cell length along the longitudinal axis was extended by 40% in the treated cells, implying stress responses to the drug treatment. More than a 200% increase in protrusions per unit surface area on the cell envelope was observed in the curvature analysis after treatment. Experiments by conventional transmission electron microscopy and atomic force microscopy were also performed, followed by comparison and discussions. In conclusion, the proposed 3D imaging method and associated analysis provide a unique tool for the assessment of antibiotic effects on multidrug-resistant bacteria at nanometer resolution.

Highly crystalline core-shell FeCo-CoFe2O4 nanowires were obtained from a three step process. Initially, CoFe2O4 nanowires were grown using electrospinning and annealing at higher temperatures. Through a thermal reduction under controlled conditions, CoFe2O4 nanostructures were converted to FeCo alloy nanowires. Then by natural oxidation, a highly crystalline shell of CoFe2O4 formed over the FeCo core structure. Structural and magnetic characterizations revealed the presence of highly crystalline FeCo-Co2FeO4 core-shell structure. Magnetically, the soft FeCo phase switches at a lower magnetic field compared to the hard CoFe2O4 phase, yielding an irregular hysteresis loop with a squeezed loop in the middle. The FeCo/CoFe2O4 core-shell is stable and it retains its structure for a prolonged duration.

In the midst of an outbreak, carbapenem-resistant Acinetobacter baumannii was grown from samples of multiple environmental sites in an intensive care unit. A commercial oxidizing disinfectant (potassium peroxomonosulphate 50%, sodium alkyl benzene sulphonate 15%, and sulphamic acid 5%) was introduced throughout the intensive care unit, and its use coincided with cessation of the outbreak.

Exposure of healthcare workers to patients with rapidly fatal infections invariably raises concerns regarding the risk of occupational acquisition. We describe acquisition of Streptococcus pyogenes by 2 nurses from a patient with fatal pneumonia and review previously reported cases of transmission of bacterial pathogens from patients with pneumonia to healthcare workers.

Neural mediation of the human cardiac response to isocapnic (IC) steady-state hypoxaemia was investigated using coarse-graining spectral analysis of heart rate variability (HRV). Six young adults were exposed in random order to a hypoxia or control protocol, in supine and sitting postures, while end-tidal PCO2 (PET,CO2) was clamped at resting eucapnic levels. An initial 11 min period of euoxia (PET,O2 100 mmHg; 13.3 kPa) was followed by a 22 min exposure to hypoxia (PET,O2 55 mmHg; 7.3 kPa), or continued euoxia (control). Harmonic and fractal powers of HRV were determined for the terminal 400 heart beats in each time period. Ventilation was stimulated (P < 0.05) and cardiac dynamics altered only by exposure to hypoxia. The cardiac interpulse interval was shortened (P < 0.001) similarly during hypoxia in both body positions. Vagally mediated high-frequency harmonic power (Ph) of HRV was decreased by hypoxia only in the supine position, while the fractal dimension, also linked to cardiac vagal control, was decreased in the sitting position (P < 0.05). However, low-frequency harmonic power (Pl) and the HRV indicator of sympathetic activity (Pl/Ph) were not altered by hypoxia in either position. These results suggest that, in humans, tachycardia induced by moderate IC hypoxaemia (arterial O2 saturation Sa,O2 85 %) was mediated by vagal withdrawal, irrespective of body position and resting autonomic balance, while associated changes in HRV were positionally dependent.