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This study presents enhanced surveillance data from 2004 to 2018 for all community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) specimens collected in Western Australia (WA), and describes the changing epidemiology over this period. A total of 57 557 cases were reviewed. Annual incidence rates increased from 86.2 cases per 100 000 population to 245.6 per 100 000 population (IRR = 2.9, CI95 2.7–3.0). The proportion of isolates carrying Panton–Valentine leucocidin (PVL)-associated genes increased from 3.4% to 59.8% (χ2 test for trend 7021.9, P < 0.001). The emergence of PVL-positive, ‘Queensland CA-MRSA’ (ST93-IV) and ‘WA 121’ (ST5-IV) accounted for the majority of increases in CA-MRSA across the study period. It is unclear why some clones are more prolific in certain regions. In WA, CA-MRSA rates increase as indices of temperature and humidity increase after controlling for socioeconomic disadvantage. We suggest climatic conditions may contribute to transmission, along with other socio-behavioural factors. A better understanding of the ability for certain clones to form ecological niches and cause outbreaks is required.
Silver nitrate cautery and bipolar electrocautery are commonly used in the treatment of epistaxis. Currently, there are no recommendations on optimum contact times or power for nasal cautery. ENT consultant practice in the UK has not previously been evaluated.
This study examined the burn depth associated with silver nitrate (75 per cent concentration) cautery and bipolar electrocautery on porcine septum samples, using varying contact times and power. ENT consultants completed a survey evaluating their practice.
Results and conclusion
ENT consultant practice of nasal cautery was shown to vary widely. Silver nitrate cautery with a contact time of less than 30 seconds does not cause a full thickness burn. The findings lend some support to bilateral cauterisation with silver nitrate. Bipolar electrocautery should be set at lower than 10 W and with a contact time of less than 4 seconds to reduce the risk of complications associated with a full thickness burn.
In 2017, Hurricane Maria exposed a colonial-era settlement at LaSoye on the Caribbean island of Dominica. Evidence suggests that this was a seventeenth- to eighteenth-century Dutch trading factory built over an earlier Kalinago settlement, and a place of early interaction between Indigenous peoples and Europeans.
The evidence underpinning the developmental origins of health and disease (DOHaD) is overwhelming. As the emphasis shifts more towards interventions and the translational strategies for disease prevention, it is important to capitalize on collaboration and knowledge sharing to maximize opportunities for discovery and replication. DOHaD meetings are facilitating this interaction. However, strategies to perpetuate focussed discussions and collaborations around and between conferences are more likely to facilitate the development of DOHaD research. For this reason, the DOHaD Society of Australia and New Zealand (DOHaD ANZ) has initiated themed Working Groups, which convened at the 2014–2015 conferences. This report introduces the DOHaD ANZ Working Groups and summarizes their plans and activities. One of the first Working Groups to form was the ActEarly birth cohort group, which is moving towards more translational goals. Reflecting growing emphasis on the impact of early life biodiversity – even before birth – we also have a Working Group titled Infection, inflammation and the microbiome. We have several Working Groups exploring other major non-cancerous disease outcomes over the lifespan, including Brain, behaviour and development and Obesity, cardiovascular and metabolic health. The Epigenetics and Animal Models Working Groups cut across all these areas and seeks to ensure interaction between researchers. Finally, we have a group focussed on ‘Translation, policy and communication’ which focusses on how we can best take the evidence we produce into the community to effect change. By coordinating and perpetuating DOHaD discussions in this way we aim to enhance DOHaD research in our region.
In traditional transit timing variations (TTVs) analysis of multi-planetary systems, the individual TTVs are first derived from transit fitting and later modelled using n-body dynamic simulations to constrain planetary masses. We show that fitting simultaneously the transit light curves with the system dynamics (photo-dynamical model) increases the precision of the TTV measurements and helps constrain the system architecture. We exemplify the advantages of applying this photo-dynamical model to a multi-planetary system found in K2 data very close to 3:2 mean motion resonance, K2-19. In this case the period of the larger TTV variations (libration period) is much longer (>1.5 years) than the duration of the K2 observations (80 days). However, our method allows to detect the short period TTVs produced by the orbital conjunctions between the planets that in turn permits to uniquely characterise the system. Therefore, our method can be used to constrain the masses of near-resonant systems even when the full libration curve is not observed.
Diversity within Shigella dysenteriae (n=40) and Shigella boydii (n=30) isolates from children living in Egypt aged <5 years was investigated. Shigella-associated diarrhoea occurred mainly in summer months and in children aged <3 years, it commonly presented with vomiting and fever. Serotypes 7 (30%), 2 (28%), and 3 (23%) accounted for most of S. dysenteriae isolates; 50% of S. boydii isolates were serotype 2. S. dysenteriae and S. boydii isolates were often resistant to ampicillin, chloramphenicol and tetracycline (42%, 17%, respectively), although resistance varied among serotypes. Pulsed-field gel electrophoresis separated the isolates into distinct clusters correlating with species and serotype. Genetic differences in trimethoprim/sulfamethoxazole and β-lactam-encoding resistance genes were also evident. S. dysenteriae and S. boydii are genetically diverse pathogens in Egypt; the high level of multidrug resistance associated with both pathogens and resistance to the most available inexpensive antibiotics underlines the importance of continuing surveillance.
We demonstrate improved compatibility of poly(ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) hole transport layer with acid-sensitive materials by addition of a simple base, NaOH or NH4OH, to the aqueous suspension to increase pH. Addition of NaOH to the acidic PEDOT:PSS allowed the deposition of PEDOT:PSS on top of an inverted poly(3-hexylthiophene):ZnO nanoparticle blend hybrid photovoltaic device, and improved device performance due to preservation of the ZnO electron acceptor. To quantitatively investigate the impact of base addition to hole transport layer properties and device performance, we deposited PEDOT:PSS with different pH values on inverted poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester bulk heterojunction devices. We find that NaOH modification results in a substantial work function decrease and series resistance increase. In contrast, the volatile NH4OH leaves PEDOT:PSS with minimal changes in film properties and device performance.
In February and in June 1998, two people developed acute hepatitis B following in-patient care in a district general hospital. Initial enquiries indicated their infections were not attributable to staff undertaking exposure-prone procedures (EPPs). We report the findings and implications of the subsequent investigation: a multi-disciplinary, multi-agency investigation, including molecular epidemiological analysis. Occupational Health records showed that staff involved in EPPs with the patients were HBsAg negative. No contact between the patients was identified nor were there failures in sterilization. The patients' HBV strains were identical, indicating a common source. A total of 231 out of 232 staff who might have treated either patient were tested for HBsAg; the remaining doctor, working abroad, was HBsAg- and HBeAg-positive and had the same HBV strain as the patients. On two occasions the doctor's hand had been cut while breaking glass vials, but there was no documentation linking these events to the two patients. The doctor had been vaccinated in 1993 and tested for anti-HBs prior to commencing work in 1997. The doctor was recalled to Occupational Health but did not attend and was not followed up. In total, 4948 patients potentially treated by the doctor received an explanatory letter and 3150 were tested for HBsAg. Only one was positive, and HBV sequencing showed no link to the doctor. Occasionally transmission of HBV from heath-care workers can occur in a non-EPP setting and the implications of this require examination by those setting national policy. Occupational Health Services should investigate clinical heath-care workers who do not respond to vaccination. They should ensure HBV carriers are identified and offer them appropriate advice to prevent transmission to patients.
Background and objective: Neurological dysfunction is a common problem after cardiac surgery with cardiopulmonary bypass (CPB). Cerebral ischaemia associated with the use of CPB may result in a release of neuronal–ischaemic markers and a subsequent cerebral inflammatory response which may additionally release inflammatory cytokines. In order to locate the origin and to quantify the release of neuronal–ischaemic markers and cytokines we investigated arterial–cerebral venous concentration gradients during and after CPB in a clinical setting.
Methods: In twenty-five patients scheduled for coronary artery bypass grafting surgery we measured the plasma concentration of neuron-specific enolase, S-100β protein as well as interleukins (IL) IL-6, IL-8 and IL-10 from arterial and cerebral venous blood samples prior to surgery (baseline), during hypothermic CPB at 32°C, after termination of bypass, as well as 2, 4 and 6 h after admission to the intensive care unit.
Results: Arterial–cerebral venous concentration gradients of neuron-specific enolase, S-100β, IL-6, IL-8 and IL-10 were neither detectable during nor after CPB. Compared to the baseline period, S-100β and neuron-specific enolase significantly increased during hypothermic CPB. After termination of CPB, neuronal–ischaemic markers as well as cytokines were increased and remained elevated during the investigated time course without reaching baseline values.
Conclusions: Although we found an overall increase in plasma concentrations of neuronal–ischaemic markers, IL-6, IL-8 and IL-10 during and after CPB, arterial–cerebral venous gradients were not detectable for any of these parameters. Our results suggest that the increase of investigated parameters associated with the use of CPB are not primarily caused by a cerebral inflammatory response but rather reflect a release from other sources in the systemic circulation.
Dendrons and dendrimers containing cyclophosphazenes units in each generation have been synthesised by the convergent route for the first time. We also demonstrate the synthesis of dendrons containing precise numbers of benzyl protected alcohol functionalities.
We have measured the transient events of the α-β martensitic transformation in nanocrystalline Ti films via single shot electron diffraction patterns with 1.5 ns temporal resolution. This was accomplished with a newly constructed dynamic transmission electron microscope (DTEM), which combines pulsed laser systems and pump-probe techniques with a conventional TEM. The DTEM thereby enables studies of transformations that are (1) far too fast to be captured by conventional bulk techniques, and (2) difficult to study with current ultrafast electron diffraction (UED) instruments (which typically require an accumulation of multiple shots for each diffraction pattern). Martensitic transformations in nanocrystalline materials meet both criteria, with their rapid nucleation, characteristic interface velocities ∼1 km/s, and significant irreversible microstructural changes. Free-standing 40-nm-thick Ti films were laser-heated at a rate of ∼1010 K/s to a temperature above the 1155 K transition point, then probed at various time intervals with a 1.5-ns-long intense electron pulse. Diffraction patterns show an almost complete transition to the β phase within 500 ns. Post-mortem analysis (after the sample is allowed to cool) shows a reversion to the α phase coupled with substantial grain growth, lath formation, and texture modification. The cooled material also shows a complete lack of apparent dislocations, suggesting the possible importance of a "massive" short-range diffusion mechanism.
A great challenge associated with current investigations of the structural strength properties of nanometrically-scaled polycrystals and/or composite materials relates to quantitative description of the continuous transition in mechanical behaviors occurring when going over to such materials from those microstructural, and larger, scale material deformation properties seemingly well-understood and modeled during the research investigations of the previous century . The consideration relates to whether the same dislocation generation/interaction mechanisms operating within the grain volumes of a conventional microstructured material, say, as compared in the same case for local deformations, dislocation or otherwise, at the grain boundary regions, are either additionally restricted from operation, or enhanced, for nanostructured materials. The deduced indication is that there should be a relatively smooth mechanical property transition, if any change at all, to be demonstrated here on the basis of available experimental and theoretical modeling results. The predicted smooth transition in behavior, however, may be upset, possibly, by failure to achieve the demanding quality control predictably needed for the combined considerations of: (1) structural characterization; (2) mechanical testing methods; and, (3) model computations, so as to allow quantification of the finer-scaled material behaviors. The combined property behavior is illustrated by application of effective low temperature grain boundary strengthening models at larger grain (or particle) sizes, then, transitioning to effective grain size weakening at the smallest grain sizes, with such weakening thought to occur because of otherwise normal high temperature diffusional or grain boundary weakening mechanisms being promoted somehow to become controlling in the practical “thought-to-be” low temperature regime.
In a study on the mechanism of stimulated petiole elongation in submerged plants, oxygen concentrations in
petioles of the flood-tolerant plant Rumex palustris were measured with micro-electrodes. Short-term submergence
lowered petiole partial oxygen pressure to c. 19 kPa whereas prolonged submergence under continuous
illumination depressed oxygen levels to c. 8–12 kPa after 24 h. Oxygen levels in petioles depended on the presence
of the lamina, even in submerged conditions, and on available light. In darkness, petiole oxygen levels in
submerged plants dropped quickly to values as low as 0.5–4 kPa. It is hypothesized that prolonged submergence
in the light is accompanied by a decrease in carbon dioxide in the petiole. Submergence-enhanced petiolar
elongation rate was compared with emergent plants. Peak daily elongation rates occurred at the end of the dark
period in emergent plants, but in the middle of the light period in submerged plants. We suggest that this shift
in daily elongation pattern is induced by dependence of growth on photosynthetically derived oxygen in
submerged plants. Implications of reduced oxygen for ethylene production are raised. Levels of 1-
aminocyclopropane-1-carboxylic acid synthase and 1-aminocyclopropane-1-carboxylic acid oxidase and ethylene
sensitivity are cited as potential factors in hypoxia-induced ethylene release.
This contribution describes the use of layer-by-layer self-limiting siloxane chemisorption processes to self-assemble structurally regular multilayer organic LED (OLED) devices. Topics discussed include: 1) the synthesis of silyl-functionalized precursor molecules for hole transport layer (HTL), emissive layer (EML), and electron transport layer (ETL) self-assembly, 2) the use of layer-by-layer self-assembly for ITO electrode modification/passivation/hole-electron balancing in a vapor-deposited device, 3) the microstructure/chemical characterization of HTL self-assembly using a prototype triarylamine precursor, 4) fabrication and properties of a hybrid self-assembled + vapor deposited two-layer LED, 4) fabrication and properties of a fully self-assembled two-layer OLED.