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To explore the opinions of the UK consultant body on endoscopic Eustachian tube balloon dilatation in the context of Eustachian tube dysfunction.
A 10-question online survey was distributed to ENT consultants currently practising in the UK (July–September 2018).
A total of 137 ENT consultants responded. Twenty-three per cent reported experience of Eustachian tube balloon dilatation, with a further 10 per cent planning to start performing the procedure. Of those performing the procedure, 16 per cent had more than two years’ experience. Thirty-two per cent were performing zero to five procedures a year. Eustachian tube balloon dilatation was primarily conducted to treat Eustachian tube dysfunction symptoms, as well as retraction pockets, baro-challenge-induced Eustachian tube dysfunction and otitis media with effusion. The most common reason for not undertaking Eustachian tube balloon dilatation was insufficient evidence of efficacy (65 per cent). Seventy-two per cent of consultants thought that creating a national database for audit and monitoring purposes would benefit the specialty.
The majority of UK ENT consultants do not practise Eustachian tube balloon dilatation, citing a lack of high-level evidence to support its use. A national database for auditing and research could facilitate the creation of guidelines.
Human immunodeficiency virus infected patients have a three-fold increased risk of head and neck squamous cell carcinoma. The British HIV Association recommends human immunodeficiency virus testing in all new diagnoses of head and neck squamous cell carcinoma.
This observational study aimed to examine the current routine practice of human immunodeficiency virus testing in patients with newly diagnosed head and neck squamous cell carcinoma, and to address the importance of this test in promoting the early diagnosis and treatment of human immunodeficiency virus.
All head and neck cancer multidisciplinary teams in England were questioned on their protocol for human immunodeficiency virus testing in new diagnoses of head and neck squamous cell carcinoma.
Only 1 out of 30 hospitals leading head and neck multidisciplinary teams (3.3 per cent) routinely offered human immunodeficiency virus testing in this high-risk patient group.
This observational study highlights that head and neck specialists are not aware of, and are consequently not complying with, routine human immunodeficiency virus testing as recommended by the British HIV Association guidelines.
Anterior Cervical Discectomy and Fusion (ACDF) is the gold standard treatment for cervical spondylosis but there is a lack of consensus in the literature regarding which type of bone graft is superior: autograft or allograft. The purpose of this study is to evaluate fusion after ACDF using a stand-alone intervertebral cage packed with autologous cervical bone shavings acquired during the procedure. Twenty patients that underwent single-level ACDF from 2011 to 2014 using a stand-alone polyetheretherketone (PEEK) cage were recruited. Patients were evaluated for evidence of bone fusion by plain films and CT scan. Fusion was primarily assessed by grading the level of trabecular bridging bone across the bone-graft interface. Odom’s criteria were used to assess clinical outcome. All interbody disc spaces achieved successful fusion at follow-up. A total of 80% (16/20) of patients had radiographic evidence of trabecular bone present both within and around the cage. The other 20% exhibited bridging bone within the cage but had evidence of minor radiolucent gaps and lack of bridging bone completely surrounding the cage. Eighty percent of patients reported excellent/good clinical outcomes. ACDF using a PEEK stand-alone cage with autograft bone shavings has a high rate of fusion and avoids potential complications of classic autograft harvesting and decreased allograft fusion rates.
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).
Leishmania spp. are sandfly-transmitted protozoa parasites that cause a spectrum of diseases in humans. Many enzymes involved in Leishmania central carbon metabolism differ from their equivalents in the mammalian host and are potential drug targets. In this review we summarize recent advances in our understanding of Leishmania central carbon metabolism, focusing on pathways of carbon utilization that are required for growth and pathogenesis in the mammalian host. While Leishmania central carbon metabolism shares many features in common with other pathogenic trypanosomatids, significant differences are also apparent. Leishmania parasites are also unusual in constitutively expressing most core metabolic pathways throughout their life cycle, a feature that may allow these parasites to exploit a range of different carbon sources (primarily sugars and amino acids) rapidly in both the insect vector and vertebrate host. Indeed, recent gene deletion studies suggest that mammal-infective stages are dependent on multiple carbon sources in vivo. The application of metabolomic approaches, outlined here, are likely to be important in defining aspects of central carbon metabolism that are essential at different stages of mammalian host infection.
The virulence of Campylobacter jejuni and C. coli isolated from various water sources was compared with that of clinical strains by in vitro assays of adhesion, invasion and cytotoxicity to HeLa cells. Variation in degree of attachment was observed, but this did not appear to be related to strain source, However, water strains were less invasive and less cytotoxic to HeLa cells than clinical strains as shown by immunofluorescence and electron microscopy.
These differences were particularly evident between clinical and water isolates of the same serotype and biotype implicated in an outbreak of campylobacter enteritis in a school. The enhanced virulence of the clinical isolates, possibly induced by passage, was confirmed by colonization tests on infant mice.
The distributions of the pennatulid anthozoans (sea pens) Virgularia mirabilis, Pennatula phosphorea and Funiculina quadrangularis in Scottish waters have previously only been extensively documented in sea lochs, by the Marine Nature Conservation Review (MNCR) surveys. Funiculina quadrangularis in particular was thought to be restricted to the deep basins of sea lochs and is classified as a nationally uncommon species. Sea pens are characterizing species in seven biotopes found in Scottish waters and are protected under the ‘Mud in Deep Water Habitat Action Plan’ of the UK Biodiversity Action Plan (UKBAP) and are also recorded in several Special Areas of Conservation. The present study has extended the existing information available on sea pens in Scottish waters. The distribution and abundance of the three sea pen species were mapped using GIS (Geographical Information System) by utilizing data from Nephrops norvegicus stock assessment video surveys carried out by Fisheries Research Services (FRS) Marine Laboratory. Distribution was shown to be aggregated for all species. Funiculina quadrangularis was present in areas outside the sea lochs, such as the South Minch and the outer mouths of most sea lochs. This study demonstrates that analysis of video footage derived from Nephrops stock assessment surveys can significantly extend our knowledge of sea pen distribution and population density. Future management of Nephrops stocks can be expected to consider impacts of fishing on non-commercial species such as sea pens as a part of the ‘ecosystem approach’ to management.
Middle Archaic earthen mound complexes in the lower Mississippi valley are remote antecedents of the famous but much younger Poverty Point earthworks. Watson Brake is the largest and most complex of these early mound sites. Very extensive coring and stratigraphic studies, aided by 25 radiocarbon dates and six luminescence dates, show that minor earthworks were begun here at ca. 3500 B.C. in association with an oval arrangement of burned rock middens at the edge of a stream terrace. The full extent of the first earthworks is not yet known. Substantial moundraising began ca. 3350 B.C. and continued in stages until some time after 3000 B.C. when the site was abandoned. All 11 mounds and their connecting ridges were occupied between building bursts. Soils formed on some of these temporary surfaces, while lithics, fire-cracked rock, and fired clay/loam objects became scattered throughout the mound fills. Faunal and floral remains from a basal midden indicate all-season occupation, supported by broad-spectrum foraging centered on nuts, fish, and deer. All the overlying fills are so acidic that organics have not survived. The area enclosed by the mounds was kept clean of debris, suggesting its use as ritual space. The reasons why such elaborate activities first occurred here remain elusive. However, some building bursts covary with very well-documented increases in El Niño/Southern Oscillation events. During such rapid increases in ENSO frequencies, rainfall becomes extremely erratic and unpredictable. It may be that early moundraising was a communal response to new stresses of droughts and flooding that created a suddenly more unpredictable food base.
Current helmet testing standards do not address the rotational components of an impact to the head. We describe a new testing paradigm used to measure the rotational acceleration of a headform and a protective helmet following an impact to the head in the horizontal plane. This impact simulation allows for the testing of currently available head protection devices in conditions thought to be important for the generation of cerebral concussion. The degree to which a particular helmet dampens rotational acceleration, and thus protects against concussion, can be assessed.
Our testing device consists of a pneumatic piston that provides a measured impact to a standard headform. Four different helmets were tested using the described paradigm.
Acceleration curves for each helmet and the corresponding headform are presented.
Clear differences in rotational acceleration were demonstrated. Possible avenues of further investigation are discussed.
The study used DNA fingerprint typing (spoligotyping and Heminested-Inverse-PCR) of Mycobacterium tuberculosis from all culture-confirmed inner London patients over a 12-month period to describe transmission. The methodology was evaluated by comparison with standard IS6110 typing and by examining its ability to identify known household clusters of cases. Isolates sharing indistinguishable typing patterns using both techniques were defined as clustered. Clusters were investigated to identify epidemiological links. The methodology showed good discriminatory power and identified known household clusters of cases. Of 694 culture-confirmed cases, 563 (81%) were typed. Eleven (2%) were due to laboratory cross-contamination and were excluded. Of the remaining 552 isolates 148 (27%) were clustered. Multivariate analysis indicated that clustering was more common in those with pulmonary smear positive disease (P<0·02); those born in the United Kingdom (P<0·0003) and in patients living in south London (P = 0·02). There was also a trend towards clustering being more common in those not known to have HIV infection (P = 0·051). The results suggest that in inner London, recent local transmission makes an important contribution to notification rates.
Potassium-bentonites have been found in the Courceyan Lower Limestone Shales near Burrington Combe and Oakhill, Somerset, consisting of thin, greenish yellow, plastic clays interbedded within a mudrock and limestone sequence. Mineralogically, the clay fraction is composed of virtually monomineralic interstratified illite-smectite containing 7–10% smectite layers. The clay fraction of the surrounding mudrocks, however, consists of an illite-chlorite dominated assemblage. Their mineral composition, trace element content, and the relative abundance of zircon crystals suggest an origin from burial of montmorillonite originally formed from volcanic ash. The presence of anomalously high trace element contents with both euhedral and rounded zircon grains in the Oakhill K-bentonites suggests a secondary or reworked origin for these samples. In contrast, the presence of a non-anomalous trace element content and large (>100 μm) euhedral zircon grains suggests that the Burrington K-bentonite is primary in origin. Modelling of whole-rock rare-earth element (REE) patterns shows that the Oakhill REE pattern can be derived from the Burrington pattern by the addition of small contributions from zircon and monazite, two major heavy minerals present. These K-bentonites probably represent the oldest Carboniferous K-bentonites so far recorded in the British Isles.
The Langmuir-Blodgett (LB) technique has been used to form two different types of multilayer films with novel molecular organizations. In the first case, a new method of fabricating superlattices of conducting polymers has been devised and studied. This method involves forming polyion complexes of acid derivatized conducting polymers with stearylamine (StNH2) and subsequently manipulating them into AB type superlattices by the LB technique. To date, superlattices consisting of isolated alternating monolayers of poly(thiophene acetic acid) (PTAA) and sulfonated polyaniline (PAn) have been studied. The layered structure of these films was found to be very similar to that of their respective homopolymer LB films, as evidenced by X-ray diffraction patterns. The conductivity of these superlattices was in the range of 10−1 S/cm, which is approximately one order of magnitude higher than that obtained with the homopolymer LB films (about 10−2 S/cm). In the second case, LB films of a novel diblock copolymer have been made, where one of the blocks is a water-insoluble polyacetylene precursor and the other block a non-conjugated, water-soluble poly(norbornene) derivative. The precursor block of the LB films could be converted to trans-polyacetylene by heating, and doped to a conductivity of 10−3 S/cm, which was significantly higher than that of cast (10−7 S/cm) or spin-coated (10−5 S/cm) films of the same material. Thus, in both cases, the unique molecular organization created by the LB technique has resulted in films with higher conductivities than those obtained by traditional casting techniques.
From 1966 to 1979, the University of Missouri, the University of Arizona, and the Illinois State Museum conducted extensive interdisciplinary investigations of Late Pleistocene peat deposits associated with springs, some extinct, in the Pomme de Terre River Valley of the Ozark Highland, Missouri (fig 1). Most of the sites are now beneath the waters of the Harry S Truman reservoir. Archaeologic investigations in the area produced a remarkably long sequence of cultural change and development during the Holocene but produced no evidence of human presence in the area prior to 11,000 years ago despite diligent excavation of favorable bone-bearing deposits.
The purpose of this note is to call attention to the convenience of glass cloth/polyester resin laminates as a means of constructing certain parts of experimental apparatus, such as small ducts or nozzles.
The advantages of the material are that it is strong, light in weight, easily worked in that heat and pressure are not required, and a high degree of accuracy and surface finish are easily achieved. For the purposes considered here, convenience in fabrication is the main consideration, since it is easier to shape the outside of a suitable male mould rather than the inside of a small duct.