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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.
This paper describes a model of electron energization and cyclotron-maser emission applicable to astrophysical magnetized collisionless shocks. It is motivated by the work of Begelman, Ergun and Rees [Astrophys. J. 625, 51 (2005)] who argued that the cyclotron-maser instability occurs in localized magnetized collisionless shocks such as those expected in blazar jets. We report on recent research carried out to investigate electron acceleration at collisionless shocks and maser radiation associated with the accelerated electrons. We describe how electrons accelerated by lower-hybrid waves at collisionless shocks generate cyclotron-maser radiation when the accelerated electrons move into regions of stronger magnetic fields. The electrons are accelerated along the magnetic field and magnetically compressed leading to the formation of an electron velocity distribution having a horseshoe shape due to conservation of the electron magnetic moment. Under certain conditions the horseshoe electron velocity distribution function is unstable to the cyclotron-maser instability [Bingham and Cairns, Phys. Plasmas 7, 3089 (2000); Melrose, Rev. Mod. Plasma Phys. 1, 5 (2017)].
Magnetic field measurements in turbulent plasmas are often difficult to perform. Here we show that for
kG magnetic fields, a time-resolved Faraday rotation measurement can be made at the OMEGA laser facility. This diagnostic has been implemented using the Thomson scattering probe beam and the resultant path-integrated magnetic field has been compared with that of proton radiography. Accurate measurement of magnetic fields is essential for satisfying the scientific goals of many current laser–plasma experiments.
Research has shown that maternal mental illness can affect mother–infant interactions with implications for infant outcomes. Severe and chronic mental illness (SMI), particularly schizophrenia, is associated with the greatest risk. Schizophrenia is also associated with impairments in attribution of mental states, ‘theory of mind’ (ToM). Recent attachment research has suggested that maternal mentalizing skills are strongly associated with attachment outcome in infants. To date, no research has explored the relationship between ToM and maternal sensitivity in mothers with SMI using standard tests of ToM. The present study was designed as an exploratory study in order to investigate this.
A total of 40 women with SMI in the postpartum period were administered a battery of ToM tasks and general neuropsychological tasks. The women were also filmed in an unstructured play session with their infants, which was coded for maternal sensitivity using the Crittenden CARE-Index.
One ToM task, the Frith–Happé Animations, predicted maternal sensitivity across all diagnoses. There was also an effect of diagnosis, with lower sensitivity observed in women with schizophrenia. ToM impairments did not fully explain the effect of diagnosis on sensitivity. Mothers of girls were rated as being more sensitive than mothers of boys.
The results suggest that ToM is a significant predictor of maternal sensitivity across all mental health diagnoses, extending the results of studies focusing on healthy populations. Clinical interventions emphasizing the importance of understanding the perspective of the infant may enhance maternal sensitivity.
We have developed a new radiography setup with a short-pulse laser-driven x-ray source. Using a radiography axis perpendicular to both long- and short-pulse lasers allowed optimizing the incident angle of the short-pulse laser on the x-ray source target. The setup has been tested with various x-ray source target materials and different laser wavelengths. Signal to noise ratios are presented as well as achieved spatial resolutions. The high quality of our technique is illustrated on a plasma flow radiograph obtained during a laboratory astrophysics experiment on POLARs.
To report our outcomes with salvage CO2 laser surgery following recurrence of laryngeal and oropharyngeal cancer after radiotherapy.
This study entailed a prospective review of patients treated with transoral laser microsurgery for recurrent laryngeal and oropharyngeal cancer between 2002 and 2010 at the Queen Elizabeth II Health Science Centre in Canada.
Sixteen patients were identified, with a mean follow up of 30.6 months. Five patients died of recurrence. Complications were common in patients with oropharyngeal cancer. The overall survival and disease-free survival rates at an average of 29.8 months follow up were 50 per cent and 68.8 per cent respectively.
Salvage surgery using transoral laser microsurgery should be considered in the management of patients with recurrent laryngeal and oropharyngeal cancer. This technique offers acceptable salvage rates with less comorbidity than other treatments.
The Carnegie Hubble Program (CHP) is a Warm Spitzer program with the aim of reducing the uncertainty in the Hubble constant to below 3%. The program is calibrated using Galactic Cepheids with precise parallax distances from the Hubble Space Telescope (HST), combined with a large sample of Cepheids in the Large Magellanic Cloud. We extend the Cepheid distance scale to the Local Group and beyond, into the regime probed by the Tully–Fisher relation. The entire program—from Galactic Cepheids to the most distant galaxies—uses the Spitzer/IRAC instrument. Completing the entire program with a single instrument on a single telescope virtually eliminates instrumental effects, whilst moving to the mid-infrared drastically reduces the reddening and metallicity effects that trouble the optical Cepheid distance scale. Our first measurement of the Hubble constant, using only two CHP galaxies tied into the HST Key Project results has produced a measurement of H0 = 74.3 ± 2.1 (systematic) km s−1 Mpc−1, which corresponds to a systematic uncertainty of 2.8%.
A faunule of silicified hypercalcified “sphinctozoan” sponges has been recovered from a clast of Upper Ordovician limestone out of the Early Devonian Karheen Formation on Prince of Wales Island in southeastern Alaska. Included in the faunule are abundant examples of the new genus Girtyocoeliana, represented by Girtyocoeliana epiporata (Rigby and Potter), and Corymbospongia adnata Rigby and Potter, along with rare Corymbospongia amplia n. sp., and Girtyocoelia(?) sp., plus common Amblysiphonella sp. 1 and rare Amblysiphonella(?) sp. 2. The assemblage is similar to that from Ordovician clasts from the eastern Klamath Mountains of northern California. This indicates that the Alexander terrane of southeastern Alaska is related paleogeographically to the lithologically and paleontologically similar terrane of the eastern Klamath Mountains.
This lithology and fossil assemblage of the clast cannot be tied to any currently known local rock units on Prince of Wales Island. Other clasts in the conglomerate appear to have been locally derived, so it is inferred that the limestone clasts were also locally derived, indicating the presence of a previously undocumented Ordovician limestone unit on northern Prince of Wales Island.
A single specimen of Hazelia palmata Walcott, 1920, was collected from the Middle Cambrian Marjum Formation near Marjum Pass, in the central House Range, western Utah. This is a first occurrence of the species outside the Burgess shale region of British Columbia, Canada. The flattened oval impression of the monaxonid demosponge shows characteristic tufts and spicule structures of the species.
Using combined epicardial echocardiography and high-fidelity intraventricular pressure recordings, the acute effects of transition to a Fontan circulation were studied in 10 patients. Measurements were made before and after cardiopulmonary bypass. The Fontan operation had no significant effect on load-dependent indices, or on a load independent index (Vmax) of ventricular systolic function. Large changes were observed in ventricular geometry. Maximum and minimum cavity dimensions were reduced, while maximum and minimum thicknesses of the posterior wall were increased.While simultaneous Doppler/intraventricular pressure measurements suggested that the compliance of the ventricle was unchanged, the pattern of atrioventricular flow changed from predominantly early diastolic (E wave) to predominantly atrial systolic (A wave) as a result of surgery in four patients. The time constant of ventricular relaxation was prolonged in all patients and five developed Doppler echocardiographic evidence of incoordinate relaxation of the ventricle, with intraventricular flow occurring during isovolumic relaxation. Thus, the Fontan operation causes acute hypertrophy of the systemic ventricle due to a sudden reduction in ventricular preload in the presence of a maintained shortening fraction. While global ventricular diastolic compliance may be unchanged by the operative procedure, filling of the ventricle during early diastole is altered as a result of incoordinate relaxation and a prolonged time constant of ventricular relaxation.
This article could be subtitled ‘Thoughts on contemplating a model of five tetrahedra inscribed in a dodecahedron’; it is an attempt to communicate the pleasure that ensues when logical reasoning is combined with a visual delight in geometrical figures.
In a recent paper  Longuet-Higgins and Parry prove that, given a general Clifford configuration of degree 5 (abbreviated to CL5), C0 say, there exist points P and Q such that the inverses of P in the circles of C0 form the points of another CL5C1, whilst the inverses of Q in the circles of C1 are the points of C0; also the inverses of Q in the circles of C0 form the points of a CL5 C–1, whilst the inverses of P in the circles of C–1 are the points of C0. This leads to an infinite chain …, C–2, C–1, C0, C1, C2, … of CL5s, each connected to the next by means of the same two points P and Q, called the poles of the chain.
If five spheres σ0, σ1, …, σ4 touch each other externally and have radii in geometrical progression, there is a dilative rotation mapping σ0, σ1, σ2, σ3, to σ1, σ2, σ3, σ4; the dilatation factor is shown to be negative. The ten points of contact of the spheres lie by fours on 15 circles, forming a (154106) configuration in inversive space. In the corresponding configuration in the inversive plane, the 15 circles meet again in 60 points, which lie by fours on 45 circles touching by threes at each of the 60 points, and forming a configuration isomorphic to that of 60 Pascal lines (associated with six points on a conic) meeting by fours at 45 points. The 45 circles arise from ten Money-Coutts configurations of nine anti-tangent cycles. Conjectures are made about other circles through the 60 points.
A quadrangle has four vertices, of which no three are collinear, and six sides joining the vertices in pairs. If the angle between each pair of the six sides is an integral multiple of π/n radians, n being an integer, the quadrangle is said to be n-adventitious . A quadrangle is adventitious if it is n- adventitious for some n. For example, the quadrangle BCDE in Fig. 1 (the original adventitious quadrangle from which all the discussion started in ) is 18-adventitious. Various problems are posed in ; in a suitably generalised form these problems can be summarised as: find all adventitious quadrangles and prove their existence by elementary geometry.