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Medical equipment can transmit pathogenic bacteria to patients. This single-institution point prevalence study aimed to characterise the types and relative amount of bacteria found on surgical loupes, headlights and their battery packs.
Surgical loupes, headlights and battery packs of 16 otolaryngology staff and residents were sampled, cultured and quantified. Plate scores were summed for each equipment type, and the total was divided by the number of users to generate mean bacterial burden scores. Residents completed a questionnaire regarding their equipment cleaning practices.
The contamination rates of loupes, headlights and battery packs were 68.75 per cent, 100 per cent and 75 per cent, respectively. Battery packs cultured more bacteria (1.58 per swab ± 1.00) than loupes (0.75 per swab ± 0.66; p = 0.024). Headlights had non-significantly greater growth (1.50 per swab ± 0.71) than loupes (p = 0.052). Bacterial growth was significantly higher from inner surfaces of loupes (p = 0.035) and headlights (p = 0.037). Potentially pathogenic bacteria were cultured from the equipment of five participants, including: Pantoea agglomerans, Acinetobacter radioresistens, Staphylococcus aureus, Acinetobacter calcoaceticus baumannii complex and Moraxella osloensis.
This study demonstrates that surgical loupes and headlights used in otolaryngology harbour non-pathogenic skin flora and potentially pathogenic bacteria.
Introduction: Direct observation is essential to assess medical trainees and provide them with feedback to support their progression from novice to competent physicians. However, learners consistently report infrequent observations, and calls to increase direct observation in medical training abound. In this study, a theory-driven approach using the Theoretical Domains Framework (TDF) was applied to systematically investigate factors that serve as barriers and enablers to direct observation in residency training. Methods: Semi-structured interviews of faculty and residents from various specialties at two large tertiary-care teaching hospitals were conducted. An interview guide based on the TDF was used to capture 14 theoretical domains that may influence direct observation. Interview transcripts were independently coded using direct content analysis by two researchers, and specific beliefs were generated by grouping similar responses. Relevant domains were identified based on the frequencies of beliefs reported, presence of conflicting beliefs, and perceived influence on direct observation practices. Results: Data saturation was achieved after 12 resident and 13 faculty interviews, with a total of 10 different specialties represented. Median postgraduate year among residents was 4 (range 1-6), and mean years of independent practice among faculty was 10.3 (SD=8.6). Ten TDF domains were identified as influencing direct observation: knowledge, skills, beliefs about consequences, social professional role and identity, intention, goals, memory/attention/decision-making, environmental context and resources, social influences, and behavioural regulation. Discord between faculty and resident intentions to engage in direct observation, coupled with the social expectation that residents should be responsible for ensuring observations occur, was identified as a key barrier. Additionally, competing demands identified across multiple TDF domains emerged as an important and pervasive theme. Conclusion: This study identified key barriers and enablers to direct observation. The influencing factors identified in this study provide a basis for the development of potential strategies aimed at embedding direct observation as a routine pedagogical practice in residency training.
Precision farming advances are providing opportunities in both production agriculture and agricultural research. For growers and agronomists, the benefits of identifying where crops are stressed, the location of weeds and estimating yields on a large scale are clear. Researchers, who have different needs, can benefit from a detailed focus on a specific characteristic, such as one disease (e.g. yellow rust). This paper will review how recent advances in technology are beginning to allow the development of specialised tools within research and agriculture and how current precision agriculture tools can be effective at measuring desirable traits.
We describe the performance of the Boolardy Engineering Test Array, the prototype for the Australian Square Kilometre Array Pathfinder telescope. Boolardy Engineering Test Array is the first aperture synthesis radio telescope to use phased array feed technology, giving it the ability to electronically form up to nine dual-polarisation beams. We report the methods developed for forming and measuring the beams, and the adaptations that have been made to the traditional calibration and imaging procedures in order to allow BETA to function as a multi-beam aperture synthesis telescope. We describe the commissioning of the instrument and present details of Boolardy Engineering Test Array’s performance: sensitivity, beam characteristics, polarimetric properties, and image quality. We summarise the astronomical science that it has produced and draw lessons from operating Boolardy Engineering Test Array that will be relevant to the commissioning and operation of the final Australian Square Kilometre Array Path telescope.
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
Obstructive sleep apnoea is a common condition that is unfortunately associated with a high rate of patient non-compliance regarding device use. Newer surgical interventions have focused on procedures at the palate level, using variants of palatoplasty and transpalatal advancement. However, the extent of tongue reduction surgery required remains controversial. The authors propose an in-between variant that combines midline glossectomy resection (with minimal mucosal sacrifice) and lateral coblation tongue channelling.
Four patients underwent a coblation-assisted Lewis and MacKay operation, which is a new technique for tongue reduction. This involved a midline glossectomy combined with lateral coblation channelling of the tongue, alone or as part of major airway reconstruction. Demographic, polysomnographic and quality of life questionnaire data were collected prospectively and analysed.
Results and conclusion:
No significant complications were noted in the four patients. (Results of the post-surgical outcomes are presented in another paper.) The coblation-assisted Lewis and MacKay operation reduced the potential complications of aggressive tongue surgery. The contours of the tongue were maintained, but significant reduction was still achieved.
PILOT (the Pathfinder for an International Large Optical Telescope) is a proposed 2.5-m optical/infrared telescope to be located at Dome C on the Antarctic plateau. Conditions at Dome C are known to be exceptional for astronomy. The seeing (above ∼30 m height), coherence time, and isoplanatic angle are all twice as good as at typical mid-latitude sites, while the water-vapour column, and the atmosphere and telescope thermal emission are all an order of magnitude better. These conditions enable a unique scientific capability for PILOT, which is addressed in this series of papers. The current paper presents an overview of the optical and instrumentation suite for PILOT and its expected performance, a summary of the key science goals and observational approach for the facility, a discussion of the synergies between the science goals for PILOT and other telescopes, and a discussion of the future of Antarctic astronomy. Paper II and Paper III present details of the science projects divided, respectively, between the distant Universe (i.e. studies of first light, and the assembly and evolution of structure) and the nearby Universe (i.e. studies of Local Group galaxies, the Milky Way, and the Solar System).
There is a need for powerful active materials in microsystem actuators. Research on thin film magnetostrictive materials has concentrated on optimising the magnetostrictive response notably by reducing the required driving magnetic field. Here we present a novel type of multilayer, where 2 alloys having different properties are coupled together. The resulting composite system represents a new material with novel characteristics, which can not be fulfilled by simple alloys. In particular here we have investigated magnetostrictive multilayers, with remarkable low field performances (i.e. very large ∂λ / ∂H).
Most magnetostrictive microactuators are based on a bimorph structure. However, these simple structures are prone to thermal drift. We present here also some results on a torsion based magnetostrictive microactuator prototype being insensitive to thermal drift.
ZnO is known to produce a wide variety of nanostructures that have enormous scope for optoelectronic applications. Using an aqueous electrochemical deposition technique, we are able to tightly control a wide range of deposition parameters (Zn2+ concentration, temperature, potential, time) and hence the resulting deposit morphology. By simultaneously conducting synchrotron x-ray absorption spectroscopy (XAS) experiments during the deposition, we are able to directly monitor the growth rates of the nanostructures, as well as providing direct chemical speciation of the films. In situ experiments such as these are critical to understanding the nucleation and growth of such nanostructures.
Recent results from in situ XAS synchrotron experiments demonstrate the growth rates as a function of potential and Zn2+ concentration. These are compared with the electrochemical current density recorded during the deposition, and the final morphology revealed through ex situ high resolution electron microscopy. The results are indicative of two distinct growth regimes, and simultaneous changes in the morphology are observed.
These experiments are complemented by modelling the growth of the rods in the transport-limited case, using the Nernst-Planck equations in 2 dimensions, to yield the growth rate of the volume, length, and radius as a function of time.
About 2·3% (16/700) of faecal specimens from renal transplant recipients and patients having home haemodialysis as well as patients attending their general practitioners with symptoms of gastroenteritis yielded Listeria species 40% of positive faeces contained more than one Listeria species or serovar. The proportion of positive specimens was similar in all three patient groups. Listeria were isolated from 5·6% (10/177) of renal transplant recipients on one or more occasions over the period of a year. The commonest species was L. monocytogenes and type 4b the commonest serovar. Carriage was more common in July and August than other times of year, and less than 28 weeks in duration. In renal transplant recipients carriage was positively related to treatment with ranitidine, consumption of more than three types of cheese in the previous 20 months, and consumption of English cheddar cheese more than once per week.
Numbers of great cormorants Phalacrocorax carbo feeding in inland waters during winter have increased throughout Europe resulting in concerns over their impacts on fisheries. Loch Leven is a world-renowned sport fishery for trout and supports a nationally important population of wintering cormorants. The relationships between brown trout stocking, regional cormorant numbers and cormorants counted during winter on Loch Leven were examined. Stocked brown trout were fin-clipped before release and gut contents from a sample of 96 cormorants shot under scientific licence were analysed. The data suggest that the number of cormorants at this site is influenced by both the stocking policy and the regional population level. Cormorant diet varied with the sex and age of birds. Overall, trout made up c. 85% of the total content by weight. Brown trout predominated in the diet, making up c. 70%, while rainbow trout occurred less frequently, making up c. 6%. Trout which could not be identified to species, made up the remainder (c. 9%). There was no significant difference in the ratios of wild and stocked brown trout sampled from the loch and from cormorant stomachs in winter. A model was constructed to investigate the likely loss of trout to cormorants roosting on the loch. It was estimated that over a 7-month period cormorants consumed 80 803 (41 617–128 248) brown and 5213 (830–12 454) rainbow trout. These estimates compared to average annual fishery catches of 5828 brown and 12 815 rainbow trout (1996–2000). Comparison with published estimates of trout populations in Loch Leven indicated a high potential for competition between the birds and the fisheries for available fish. It is suggested that stocking has led to an increase in cormorant numbers and the subsequent increase in predation may have prevented any increase in the trout population or in fishery catches.
The success of Linum usitatissimum as a commercial crop depends on its value for seed/oil (linseed)
and/or fibre/straw production (flax). In the present study we evaluated nine linseed × linseed and two
linseed × flax crosses for their potential to produce recombinant inbred lines (RILs) that give higher
yields for dual-purpose (high seed–high fibre) traits. Analysis of the early generations indicated that
while all crosses segregated for seed weight, straw weight, capsule weight and total plant weight, some
crosses lacked the necessary genetic diversity to produce superior RILs. The performance of F3
families supported this conclusion as only two crosses were identified which had adequate potential
to produce improved RILs with high seed and straw/fibre yields. The four most heterotic crosses
identified in a previous experiment showed little potential for transgressive recombinants, although
the best of these RILs would make better dual-purpose varieties compared to existing cultivars.
Genotypic correlations were generally positive and should increase the chances of extracting RILs
producing both high seed/oil and straw/fibre yields.
The commercial future of Linum usitatissimum is intrinsically
linked to its cultivation as a dual-purpose
crop for producing increased seed and fibre yields. The present
study evaluates 36 F1 crosses
derived from nine linseed/flax accessions for their potential as dual-purpose
cultivars and/or their
suitability for extracting new recombinants producing high seed yield as
well as increased fibre
output. The quantitative analysis indicated that variation
between the F1 families is largely but not
exclusively due to the additive and non-additive (dominance) effects of
genes. Dominance is high for
plant height (H1), height at maturity (HMT), number of branches (NBr) and
seed weight (SdWt)
while 100 seed weight (Wt100) displays no dominance at all. The repeatability
the heritability of each trait, vary from low (0·20) for number
of branches (NBr) to high (0·71) for
height at flowering time (HFT). The dual-purpose traits such as seed weight
(SdWt) and straw weight
(StWt) were only moderately inherited while flowering time (FT) and various
heights were rather
highly heritable. A moderate and positive correlation (r=0·57)
between StWt and SdWt, and a
completely independent inheritance of Wt100 suggested that there are good
chances of combining
these traits into a single genotype. The phenotypic performance of the
crosses also confirmed this
trend and at least four crosses showed superior performance for both SdWt
and StWt compared to
their parental lines. All these crosses involved a linseed line (B3) as
a common parent and the second
parent was either another linseed line (A1 and A3) or a flax accession
(K3 and L2); none of the
flax×flax crosses showed good potential for seed yield. While all
four crosses possess the potential
to become highly productive, dual-purpose, hybrid varieties, the extraction
of desirable inbred lines
from them, however, may prove difficult because the superior performance
of the hybrids seems
largely due to strong unidirectional dominance and high SCA effects.
The genetic relatedness of twenty isolates of Paecilomyces
was determined by comparison of the products of polymerase
chain reaction amplification of anonymous regions of genomic DNA with
single arbitrary sequence oligonucleotide primers (RAPD
analysis). Isolates were collected from seven insect species in eastern
Canada and they differed greatly in cultural and morphological
phenotype. All P. farinosus isolates were clearly distinguished
from three other entomopathogenic fungi, including P. fumosoroseus.
RAPD banding patterns did not, however, correlate with ecological
backgrounds or morphological phenotypes of P. farinosus
isolates. These observations support the conclusion that P. farinosus
from eastern Canada is not composed of strains which can be
separated on the basis of the ecological or morphological criteria selected.