A cross sectional study of water quality from dental unit water lines in dental practices in the West of Scotland

OBJECTIVE: To determine the microbiological quality of water from dental units in a general practice setting and current practice for disinfection of units. DESIGN: A cross-sectional study of the water quality from 40 dental units in 39 general practices and a questionnaire of the disinfection protocols used in those practices. SETTING: NHS practices in primarydental care. SUBJECTS: Thirty-nine general practices from the West of Scotland. METHODS: Water samples were collected on two separate occasions from dental units and analysed for microbiological quality by the total viable count (TVC) method. Water specimens were collected from the triple syringe, high speed outlet, cup filler and surgery tap. Each participating practitioner was asked to complete a questionnaire. Results Microbial contamination was highest from the high speed outlet followed by the triple syringe and cup filler. On average, the TVC counts from the high speed water lines at 37 degrees C and for the high speed lines, triple syringe and cup filler at 22 degrees C were significantly higher than that from the control tap water specimens. The study included units from 11 different manufacturers with ages ranging from under one year to over eight years. The age of the dental unit analysed did not appear to influence the level of microbial contamination. Five of the practices surveyed used disinfectants to clean the dental units but these had no significant effect on the microbiological quality of the water. The majority of dental units (25 out of 40) were never flushed with water between patients. A number of different non-sterile irrigants were used for surgical procedures. CONCLUSION: The microbiological quality of water from dental units in general dental practice is poor compared with that from drinking water sources. Suitable sterile irrigants should be used for surgical procedures in dental practice. Further work is required for pragmatic decontamination regimens of dental unit water lines in a general dental practice setting

Patients’ experiences of lupus related foot problems : a qualitative investigation

Background: Systemic lupus erythematosus (SLE) can present with a variety of symptoms. Previous research has shown there is a high prevalence of lower limb and foot problems in patients with SLE associated with the musculoskeletal, vascular and neurological changes. Furthermore, there is a high prevalence of infections affecting the feet and a range of common skin and nail problems. However, it is not known how these foot problems impact upon people’s lives. Therefore, we aimed to explore this using a qualitative approach. Method: Following ethical approval, 12 participants were recruited who had a diagnosis of SLE, current and/or past experience of foot problems and were over 18 years in age. Following consent, interviews were carried out with an interpretivist phenomenological approach to both data collection and analysis. Results: Seven themes provide insight into: foot problems and symptoms; the impact of these foot problems and symptoms on activities; disclosure and diagnosis of foot problems; treatment of foot problems and symptoms; perceived barriers to professional foot care; unanswered questions about feet and foot care; and identification of the need for professional foot care and foot care advice. Conclusion: These participants tend to “self-treat” rather than disclose that they may need professional foot care. A lack of focus upon foot health within a medical consultation is attributed to the participant’s belief that it is not within the doctor’s role, even though it is noted to contribute to reduced daily activity. There is a need for feet to be included as a part of patient monitoring and for foot health management to be made accessible for people with SLE

Cyclotrimerisation of isocyanates catalysed by low-coordinate Mn(II) and Fe(II) m-terphenyl complexes

Two- and three-coordinate m-terphenyl complexes of manganese and iron are efficient catalysts for the selective cyclotrimerisation of primary aliphatic isocyanates affording isocyanurates in short reaction times and under mild conditions

Discrete cilia modelling with singularity distributions

We discuss in detail techniques for modelling flows due to finite and infinite arrays of beating cilia. An efficient technique, based on concepts from previous ‘singularity models’ is described, that is accurate in both near and far-fields. Cilia are modelled as curved slender ellipsoidal bodies by distributing Stokeslet and potential source dipole singularities along their centrelines, leading to an integral equation that can be solved using a simple and efficient discretisation. The computed velocity on the cilium surface is found to compare favourably with the boundary condition. We then present results for two topics of current interest in biology. 1) We present the first theoretical results showing the mechanism by which rotating embryonic nodal cilia produce a leftward flow by a ‘posterior tilt,’ and track particle motion in an array of three simulated nodal cilia. We find that, contrary to recent suggestions, there is no continuous layer of negative fluid transport close to the ciliated boundary. The mean leftward particle transport is found to be just over 1 μm/s, within experimentally measured ranges. We also discuss the accuracy of models that represent the action of cilia by steady rotlet arrays, in particular, confirming the importance of image systems in the boundary in establishing the far-field fluid transport. Future modelling may lead to understanding of the mechanisms by which morphogen gradients or mechanosensing cilia convert a directional flow to asymmetric gene expression. 2) We develop a more complex and detailed model of flow patterns in the periciliary layer of the airway surface liquid. Our results confirm that shear flow of the mucous layer drives a significant volume of periciliary liquid in the direction of mucus transport even during the recovery stroke of the cilia. Finally, we discuss the advantages and disadvantages of the singularity technique and outline future theoretical and experimental developments required to apply this technique to various other biological problems, particularly in the reproductive system

An ALMA Survey of H₂CO in Protoplanetary Disks

H₂CO is one of the most abundant organic molecules in protoplanetary disks and can serve as a precursor to more complex organic chemistry. We present an Atacama Large Millimeter/submillimeter Array survey of H₂CO toward 15 disks covering a range of stellar spectral types, stellar ages, and dust continuum morphologies. H₂CO is detected toward 13 disks and tentatively detected toward a fourteenth. We find both centrally peaked and centrally depressed emission morphologies, and half of the disks show ring-like structures at or beyond expected CO snowline locations. Together these morphologies suggest that H₂CO in disks is commonly produced through both gas-phase and CO-ice-regulated grain-surface chemistry. We extract disk-averaged and azimuthally-averaged H₂CO excitation temperatures and column densities for four disks with multiple H₂CO line detections. The temperatures are between 20–50 K, with the exception of colder temperatures in the DM Tau disk. These temperatures suggest that H₂CO emission in disks generally emerges from the warm molecular layer, with some contributions from the colder midplane. Applying the same H₂CO excitation temperatures to all disks in the survey, we find that H₂CO column densities span almost three orders of magnitude (~5 × 10¹¹–5 × 10¹⁴ cm⁻²). The column densities appear uncorrelated with disk size and stellar age, but Herbig Ae disks may have less H₂CO compared to T Tauri disks, possibly because of less CO freeze-out. More H₂CO observations toward Herbig Ae disks are needed to confirm this tentative trend, and to better constrain under which disk conditions H₂CO and other oxygen-bearing organics efficiently form during planet formation

Duality in Binocular Rivalry: Distinct Sensitivity of Percept Sequence and Percept Duration to Imbalance between Monocular Stimuli

Visual perception is usually stable and accurate. However, when the two eyes are simultaneously presented with conflicting stimuli, perception falls into a sequence of spontaneous alternations, switching between one stimulus and the other every few seconds. Known as binocular rivalry, this visual illusion decouples subjective experience from physical stimulation and provides a unique opportunity to study the neural correlates of consciousness. The temporal properties of this alternating perception have been intensively investigated for decades, yet the relationship between two fundamental properties - the sequence of percepts and the duration of each percept - remains largely unexplored

Cryptic Eimeria genotypes are common across the southern but not northern hemisphere

The phylum Apicomplexa includes parasites of medical, zoonotic and veterinary significance. Understanding the global distribution and genetic diversity of these protozoa is of fundamental importance for efficient, robust and long-lasting methods of control. Eimeria spp. cause intestinal coccidiosis in all major livestock animals and are the most important parasites of domestic chickens in terms of both economic impact and animal welfare. Despite having significant negative impacts on the efficiency of food production, many fundamental questions relating to the global distribution and genetic variation of Eimeria spp. remain largely unanswered. Here, we provide the broadest map yet of Eimeria occurrence for domestic chickens, confirming that all the known species (Eimeria acervulina, Eimeria brunetti, Eimeria maxima, Eimeria mitis, Eimeria necatrix, Eimeria praecox, Eimeria tenella) are present in all six continents where chickens are found (including 21 countries). Analysis of 248 internal transcribed spacer sequences derived from 17 countries provided evidence of possible allopatric diversity for species such as E. tenella (FST values ⩽0.34) but not E. acervulina and E. mitis, and highlighted a trend towards widespread genetic variance. We found that three genetic variants described previously only in Australia and southern Africa (operational taxonomic units x, y and z) have a wide distribution across the southern, but not the northern hemisphere. While the drivers for such a polarised distribution of these operational taxonomic unit genotypes remains unclear, the occurrence of genetically variant Eimeria may pose a risk to food security and animal welfare in Europe and North America should these parasites spread to the northern hemisphere

Horseplay, care and hands on hard work: gendered strategies of a project manager on a construction site

The discourse of managerial expertise favours rational analysis and masculine ideals but contemporary management literature also recognises the value of well-being and employee voice in the workplace. Drawing upon narrative analysis of interview data, we share unique insights into the lived experiences of Laura, one female project manager who recently managed a construction site in the Midlands in the UK. In contrast to previous research which indicates that female managers tend to conform to quite a traditional set of gender behaviours, Laura embraces a range of workplace appropriate gendered strategies, such as hard work and horseplay, together with sensitivity and caring. She draws from this mix of gendered strategies in negotiating between two different discourses of construction; one professional and one tough and practical. Her behaviour both reproduces the masculine ideals (through horseplay and heroic management) and opens up possibilities for modernising construction management (by caring). It is this combination of strategies that is at the heart of tacit expertise for Laura. Theoretically, the discussion adds to the development of a more nuanced understanding of management expertise as situated and person specific knowledge that draws on both the explicit and tacit. Specifically, the centrality of gendered strategies beyond the masculine ideals to success on site is highlighted

Working through the pain… and getting on with it — some patients’ experiences of living with Lupus-related foot problems

Background: Along with its skin manifestations, SLE can present with a variety of musculoskeletal signs and symptoms and vascular problems that can affect the feet. Furthermore, there is the potential for reduced tissue viability, leading to thinning of the skin and/or callus formation. Further, systemic resistance to viral, bacterial and fungal infections may be reduced and, together with poor tissue viability, create the opportunity for these infections to proliferate in the feet. A recent survey by the same authors (unpublished) has shown a high prevalence of these infections, with many experiencing the impact of vascular and musculoskeletal problems. To date there is no research that has explored the impact of foot problems on people’s lives. Methods: Following ethical approval, 12 participants who fulfilled the inclusion criteria were recruited: diagnosed with SLE (ACR diagnosis), current and/or past experience of foot/lower limb problems and age �18 years. Consent was obtained and then conversational-style interviews were carried out with an interpretivistic phenomenological approach. The interviews were digitally recorded and complemented by field notes. An opening question was used for all participants: ‘Tell me about your experiences of having foot problems?’ If necessary, further trigger questions were used in order to maintain the conversation and the focus on foot problems. Data were transcribed verbatim and analysed using a thematic framework approach. The transcripts were verified by the participants and were analysed by a second researcher in order to add to the credibility of the analyses. Results: The data was organized into seven themes: Foot problems and symptoms—what they are and the feeling associated with them; Experiences of foot problems being diagnosed; Impact of foot problems on activities; Treatment of foot symptoms/problems; Perceived obstacles to professional foot care; Unanswered questions about feet and foot care; and Recognition of the need for professional foot care and foot care advice. These people experienced a wide variety of foot problems that impact significantly on activities. Some reported working through the pain in order to achieve visible normality while experiencing the negative emotions of anger, frustration and anxiety. Although some had experienced professional foot care, there were obstacles to the foot problems being diagnosed, resulting in many unanswered questions and some inappropriate selfmanagement. Conclusion: Despite reporting foot pain, negative emotions and activity restrictions related to their foot symptoms, people with SLE tend to get on with it and self-treat rather than seeking professional foot care. The lack of focus on the feet in the medical consultation is caused by the participants’ belief that it is not the consultant’s role. There is a clear need for foot assessments to be included in the medical consultation and for professional foot care to be provided