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To describe dentists' perceptions of their professional roles, including the reasons why they make, accept or decline patient referrals within primary dental care in England.Qualitative semi-structured interviews, conducted via Skype, telephone or face-to-face. Transcripts were analysed using thematic analysis and typologies were developed.Ten general dental practitioners (GDPs) and 12 community dentists working in England.Five main themes were identified: professional independence, the nature of dental care, the business of dentistry, obscure rules and 'no man's land'. This final theme described a notional gap between GDPs' and community dentists' responsibilities towards vulnerable people, who were perceived by participants to include frail older people, anxious and socially marginalised adults and children with high levels of disease. Three typologies of dentists were generated. 'Entrepreneurs' felt no allegiance to the National Health Service and no obligation to treat vulnerable patients. 'Altruistic carers' were committed to caring for exceptionally deserving patients. 'Pragmatic carers' tried to provide relational dental care (time and emotional support) for vulnerable patients but encountered discouraging systemic barriers.Dentists' perceptions of their roles may influence whether and how they provide access to primary dental care for vulnerable people through referral systems. Access issues may exacerbate the oral health inequalities experienced by vulnerable groups. Based upon the findings, approaches are proposed that may encourage and enable the dental workforce to support vulnerable people actively to receive primary dental care.

The tephra dispersal mechanisms of rhyolitic glaciovolcanic eruptions are little known, but can be investigated through the correlation of eruptive products across multiple depositional settings. Using geochemistry and geochronology, we correlate a regionally important Pleistocene tephra horizon—the rhyolitic component of North Atlantic Ash Zone II (II-RHY-1)—and the Thórsmörk Ignimbrite with rhyolitic tuyas at Torfajökull volcano, Iceland. The eruption breached an ice mass >400 m thick, leading to the widespread dispersal of II-RHY-1 across the North Atlantic and the Greenland ice sheet. Locally, pyroclastic density currents traveled across the ice surface, depositing the variably welded Thórsmörk Ignimbrite beyond the ice margin and ~30 km from source. The widely dispersed products of this eruption represent a valuable isochronous tie line between terrestrial, marine, and ice-core paleoenvironmental records. Using the tephra horizon, estimates of ice thickness and extent derived from the eruption deposits can be directly linked to the regional climate archive, which records the eruption at the onset of Greenland Stadial 15.2.

The geology of Tindfjallajökull volcano, southern Iceland, is presented as a 1:50,000 scale map. Field mapping was carried out with a focus on indicators of past environments. A broad stratocone of interbedded fragmental rocks and lavas was constructed during Tindfjallajökull’s early development. This stratocone has been dissected by glacial erosion and overlain by a variety of mafic to silicic volcanic landforms. Eruption of silicic magma, which probably occurred subglacially, constructed a thick pile of breccia and lava lobes in the summit area. Mafic to intermediate flank eruptions continued through to the end of the last glacial period, producing lavas, hyaloclastite-dominated units and tuyas that preserve evidence of volcano-ice interactions. The Thórsmörk Ignimbrite, a regionally important chronostratigraphic marker, is present on the SE flank of the volcano. The geological mapping of Tindfjallajökull gives insights into the evolution of stratovolcanoes in glaciated regions and the influence of ice in their development.

Low moduli cell culture substrates can be used to apply dynamic mechanical strain to cells, by surface deformation. Understanding the surface interaction with cells is critical to improving cell adhesion and normal growth. A medical grade polyurethane (PU), Chronoflex AL 80A, was modified by oxygen plasma etching and characterised by X-ray photoelectron spectroscopy. Etching resulted in increased cross-linking at the isocyanate bond and formation of new oxygen moieties. The model, derived from patent data and XPS data of the unetched PU, indicated that the additional oxygen was likely to be hydroxyl and carbonyl groups. Etched membranes enhanced protein adhesion, resulting in full surface coverage compared to unetched PU. The etched PU supported cell adhesion and spreading, while the unetched PU was not conducive to monolayer formation.

Bioreactors can be used for mechanical conditioning and to investigate the mechanobiology of cells in vitro. In this study a polyurethane (PU), Chronoflex AL, was evaluated for use as a flexible cell culture substrate in a novel bioreactor capable of imparting cyclic uniaxial tensile strain to cells. PU membranes were plasma etched, across a range of operating parameters, in oxygen. Contact angle analysis and X-ray photoelectron spectroscopy showed increases in wettability and surface oxygen were related to both etching power and duration. Atomic force microscopy demonstrated that surface roughness decreased after etching at 20 W but was increased at higher powers. The etching parameters, 20 W 40 s, produced membranes with high surface oxygen content (21%), a contact angle of 66° ± 7° and reduced topographical features. Etching and protein conditioning membranes facilitated attachment, and growth to confluence within 3 days, of MG-63 osteoblasts. After 2 days with uniaxial strain (1%, 30 cycles/min, 1500 cycles/day), cellular alignment was observed perpendicular to the principal strain axis, and found to increase after 24 h. The results indicate that the membrane supports culture and strain transmission to adhered cells. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 2356–2364, 2014.

We examined age-related changes in energetic status and reproductive effort of lake whitefish (Coregonus clupeaformis) and walleye (Sander vitreus) populations in Lakes Winnipeg and Ontario. We predicted, based on life history theory, that both species would exhibit declines in somatic energy stores and increases in the proportion of their energy reserves allocated to reproduction as they aged. These predicted trends were evident for walleye but not for lake whitefish, and the contrast between species was most pronounced for females. Walleye devoted an increasingly larger proportion of their body lipids to gonad development as they got older whereas lake whitefish devoted an increasingly smaller proportion. Between-species differences for some reproductive traits, particularly gonad size (GSI) and relative fecundity, were not consistent between the two lakes. Lake whitefish follow a strategy of lower relative fecundity, larger eggs, and lower egg lipid content compared to walleye. Differences between these species in the gamete quantity and quality of different age classes suggest that age-structured population models parameterized for one species should be applied to other species with caution.

Moles MD, Johnston TA, Robinson BW, Bernard AM, Wilson CC, Wiegand MD, Leggett WC. Reproductive divergence between growth forms of Lake Winnipeg walleye (Sander vitreus). Ecology of Freshwater Fish 2011: 20: 52–66. © 2010 John Wiley & Sons A/S Abstract – Growth polymorphisms occur in many fish species, particularly in northern temperate freshwater lakes. The only known growth polymorphism in walleye (Sander vitreus) is in Lake Winnipeg, Canada, where slow-growing (dwarf) and fast-growing (normal) morphotypes co-exist. We examined differences in reproductive traits between forms to determine whether divergence in growth rates was accompanied by divergence in reproductive strategies and also assessed the genetic composition of both forms using mitochondrial and microsatellite DNA to determine their origin and potential reproductive isolation. Both sexes of the dwarf form produced relatively larger gonads than the normal form. Female dwarfs also had a lower liver lipid concentration, a higher ovary lipid concentration, and produced relatively larger eggs compared to the normal form. There was also some indication that dwarf and normal females differed in the fatty acid profiles of their egg lipids. Population genetic analysis based on partial sequencing of the mitochondrial control region and genotyping nine microsatellite loci indicated a single interbreeding population and sympatric origin for both morphotypes. The dwarf form appears to make a relatively larger reproductive investment at a given body size, and the differences between the two forms may result from plastic developmental responses to subtle differences in niche use.

Ecologically related polymorphisms occur in many northern freshwater fish populations and are distinguished by alternate phenotypes consistently associated with differential use of habitats or resources. We tested for polymorphism in walleye (Sander vitreus (Mitchill, 1818)) in the south basin of Lake Winnipeg, where evidence suggests that “dwarf” and “normal” growth forms may coexist. Morphometric comparisons of these growth forms at similar size demonstrated significant differences in the relative sizes of head, snout, eye, and mouth, collectively suggesting dwarf individuals inhabit a more benthic niche than normal morphs. Stable isotope analysis did not support this morphometric interpretation, however, as δ13C and δ15N isotope signatures were similar between similar-sized individuals of both forms, but differed from those of large normal walleye. Walleye from Lake Winnipeg do not seem to exhibit a simple resource polymorphism where different ecotypes are associated with alternate habitats throughout their life history, nor do they exhibit characteristics of a simple mating polymorphism. We suggest the walleye from Lake Winnipeg represent two growth forms sharing a common juvenile habitat followed by the normal form shifting into an alternative adult niche.

Objective: To describe signalment, clinical findings, imaging and treatment of intestinal sand impaction in the dog. Methods: Medical records of dogs with radiographic evidence of small intestinal sand impaction were reviewed. Results: Sand impaction resulting in small intestinal obstruction was diagnosed in eight dogs. All dogs presented with signs of vomiting. Other clinical signs included anorexia, lethargy and abdominal pain. Radiographs confirmed the presence of radio-opaque material consistent with sand causing distension of the terminal small intestine in all dogs. Four dogs were treated surgically for their impaction and four dogs were managed medically. Seven of the eight dogs survived. Clinical Significance: Both medical and surgical management of intestinal sand impaction in the dog can be effective and both afford a good prognosis for recovery.

Summary Objective: To investigate arterial vascularity at the level of the proximal tibia as a potential source of the severe intra-operative haemorrhage, which has been previously reported as a complication during tibial plateau levelling osteotomy (TPLO) and triple tibial osteotomy (TTO) surgeries in dogs. To devise a surgical approach for the management of this complication. Method: Eight pelvic limbs from five canine cadavers were dissected and the vascular structures at the level of the proximal tibia were identified and photographed. An arterial phase angiogram was performed on a sixth cadaver to further describe the vasculature in situ. Additional dissection was performed on four pelvic limbs to devise a medial surgical approach to the popliteal artery and the cranial tibial artery proximal to the stifle. Results: The cranial tibial artery was identified as the most likely source of profuse haemorrhaging if damaged during proximal tibial osteotomy. Its course and branching are described. A simple medial approach to the popliteal artery at the level of its bifurcation into the cranial and caudal tibial arteries was developed. Clinical relevance: Understanding of the vascular anatomy at the level of the proximal tibia may prevent iatrogenic damage and resulting haemorrhage during TPLO and TTO surgeries. Temporary occlusion of the cranial tibial artery can be achieved through a simple medial approach, proximal to the stifle, in the event of severe haemorrhage associated with TPLO or TTO.

Summary Objective: To report the surgical findings and early post-operative complications of triple tibial osteotomy (TTO) for the treatment of cranial cruciate ligament disruption in dogs. Methods: Clinical records of 84 dogs (97 stifles) that had TTO procedures were reviewed. Surgical findings and postoperative complications were assessed. A complication was defined as any undesirable outcome resulting from TTO that required further diagnostic investigation or surgical treatment. Results: Mean tibial wedge angle was 13.6 degrees (range 10–20). Incomplete tibial crest osteotomy was achieved in 79% of TTO procedures. Implants were placed in the tibial crest in 67% of stifles. Early postoperative complications occurred in 23% of joints, and included avulsion of the tibial crest (9.1%), fracture at the distal cortical attachment of the tibial crest (6.2%), fibula fracture (4.1%), patellar tendonitis (3.1%), late meniscal injury (3.1%), implant complications (3.1%) and patellar fracture (2.1%). Increased patient age (p = 0.023), increased wedge angle (p = 0.009) and intra-operative fracturing of the cranial tibial cortex (p = 0.017) were significantly associated with postoperative tibial crest avulsion. Implants did not prevent tibial crest avulsion. Increased patient age (p = 0.012) was significantly associated with tibial crest fracture. Clinical relevance: Tibial crest avulsion and fracture are the most common postoperative complications for TTO. Late meniscal injury is uncommon after TTO.

The effects of delayed fertilization on embryonic viability in walleye Sander vitreus were examined using laboratory fertilization and incubation trials. Both fertilization success (survival to 10 h post-fertilization) and embryonic survival (from 10 to 168 h post-fertilization) generally declined with increasing ova storage time but trends varied significantly among females. Embryonic survival of individual egg batches was positively related to fertilization success. The slope of the relationship between fertilization success and ova storage time was negatively related to maternal fork length indicating that ova quality declined more rapidly with storage time for larger females than for smaller females. In contrast, the slope of the early embryonic survival v. ova storage time relationship was not significantly related to maternal size.

A key requirement of effective fisheries management is a better understanding of the mechanisms driving recruitment variability. Recent research suggests that the quantity and quality of gametes produced by fish is closely linked to the availability of surplus energy, usually stored as lipid. We sampled mature walleye (Sander vitreus) from seven populations across Canada to determine if indices of reproductive effort were positively related to indices of adult nutrient reserves, primarily body lipid concentration. Populations varied greatly in growth rates, body lipid con- tents, and reproductive traits. Within-population trends between indices of reproductive effort and parental body traits were highly variable. Body lipid concentration was most closely related to gonad lipid concentration, but not in all populations. Among populations, relative fecundity and ovary lipid concentrations were positively related, and egg size was negatively related to whole-body lipid concentrations; no trends were evident for males. Our results suggest that relationships between walleye reproductive effort and body lipid reserves may be more complex than previously thought. Resume : Un amenagement halieutique efficace necessite une meilleure comprehension des mecanismes explicatifs de la variabilite du recrutement. Des etudes recentes laissent croire que la quantite et la qualite des gametes produits par un poisson sont intimement liees a la disponibilite d'energie excedentaire, generalement accumulee sous forme de lipi- des. Nous avons echantillonne des dores (Sander vitreus) matures de sept populations provenant de divers sites d'un bout a l'autre du Canada afin de determiner si les indices d'effort reproductif sont en relation positive avec les indices d'accumulation de nutriments chez les adultes, en particulier avec le contenu lipidique du corps. Il y a parmi les popu- lations une forte variation dans les taux de croissance, les contenus lipidiques du corps et les caracteristiques reproduc- tives. Les tendances a l'interieur de chaque population sont tres variables entre les indices d'effort reproductif et les caracteristiques corporelles des parents. La concentration de lipides dans le corps est plus souvent reliee a la concentra- tion de lipides dans les gonades, mais pas dans toutes les populations. Dans l'ensemble des populations, il y a une cor- relation positive entre la fecondite relative et le contenu lipidique des ovaires, ainsi qu'une correlation negative entre la taille des oeufs et le contenu lipidique du corps entier; aucune tendance ne ressort chez les mâles. Nos resultats indi- quent que les relations entre l'effort reproductif du dore et les reserves corporelles de lipides sont plus complexes qu'on ne le croyait.

Relationships between indices of condition and measures of proximate body composition were examined among and within nine populations of mature walleyes Sander vitreus that varied widely in growth rate and lipid status. Body condition, measured as the residuals from mass versus length regressions, was negatively related to mean water content and positively related to mean lipid content among populations. When the roles of water and lipid content were examined simultaneously within populations, most of the variance in condition was accounted for by lipid content. The strength of the relationships between various condition indices and body proximate composition varied considerably among populations but less between sexes within populations. Furthermore, the strength and nature of these relationships was not strongly influenced by the choice of mass-at-length index (residuals, relative condition, relative weight, or Fulton's K). The visceral-somatic index and muscle lipid content both exhibited slig...

An 11-year-old, 7 kg male neutered domestic shorthair cat, presented to the University Veterinary Hospital (UVH) for investigation of chronic tachypnoea and dyspnoea. Radiographs, bronchoscopy and computerised tomography (CT) demonstrated an intra-tracheal mass measuring 13 mm×5 mm×6 mm arising from the right wall of the caudal trachea immediately cranial to the carina. Due to size and position, debulking and subsequent cryosurgery were attempted to minimise the amount of tissue removed and prevent recurrence. A combination of anaesthetic techniques was required to allow cryotherapy, with the trachea open whilst maintaining adequate ventilation. This case report demonstrates that cryotherapy in conjunction with anaesthetic planning, can achieve a positive outcome for the cat.

Ultrasound modulated fluorescence tomography (USMFT) has the potential to be a useful technique to obtain fluorescence images with optical contrast and ultrasound (US) resolution in deep tissue. However, due to the intrinsic incoherent properties of fluorescence and the low modulation depth, the signal-to-noise ratio (SNR) and image contrast are poor. In this paper, the feasibility of using pyrene-labelled nanosize liposomes as contrast agents to improve the modulation depth in USMFT is investigated by using a light-scattering technique. Compared with microbubbles (MBs), which have been applied to USMFT to improve the modulation depth, liposomes are more stable and they can be manufactured with good repeatability. Also liposomes have a lower US scattering coefficient due to their liquid core as compared to the gas core of MBs, which can be advantageous when switching on fluorescence in a region of interest is required. Pyrene can form excimer fluorescence when in close proximity to other pyrene molecules. The exposure of these liposomes to US can change the collision rate of the pyrene molecules and hence modulate the optical emission. In the current work, 100 nm sized liposomes composed of varying concentrations of pyrene-labelled phospholipids were investigated to identify a suitable liposome-based US contrast agent candidate. The fluorescence emission of the pyrene-labelled liposomes insonified by continuous US were studied. It has been observed that the excimer emission from 0.5 mol% pyrene-labelled liposome is US sensitive at pressures between 1.4 MPa and 2.7 MPa. Possible fluorescence modulation mechanisms and application of pyrene-labelled liposomes for high-resolution, high-contrast fluorescence imaging are also discussed.

Established in 2007, Peninsula Dental School offers a highly innovative, enquiry-based, student-led, patient-centred curriculum. It is one of the first dental schools in UK to be based exclusively in a primary care setting. This study was carried out to evaluate the academic environment at Peninsula Dental School and to identify differences between expectations of new entrants and perceptions of senior cohorts.This was a cross-sectional survey utilising an online questionnaire based on Dundee Ready Educational Environment Measure (DREEM). The subjects were 234 dental students from all years in this enquiry-based Bachelor of Dental Surgery programme.The response rate to the questionnaire was 56.42% with an equal gender distribution of the participants. The overall mean DREEM score of the four cohorts was 143.58 (SD ± 20.84), and the mean score for individual items was 2.87 (SD ± 0.41). The reliability of the DREEM data as a whole was strong (α = 0.93). The difference in questionnaire means for the new entrants and the senior cohorts was not significant (P0.05). The ANOVA results showed that there were no significant effects of age, gender or ethnicity on the mean DREEM scores. The MANOVA results showed a significant effect of ethnicity with regard to perceptions of teachers and atmosphere.An enquiry-based, student-centred curriculum at the Peninsula Dental School provides a positive academic environment for the students.

To systematically review the evidence of effectiveness of surgical vs. non-surgical therapy for the treatment of chronic periodontal disease.A search was conducted for randomized controlled trials of at least 12 months duration comparing surgical with non-surgical treatment of chronic periodontal disease. Data sources included the National Library of Medicine computerised bibliographic database MEDLINE, and the Cochrane Oral Health Group (COHG) Specialist Trials Register. Screening, data abstraction and quality assessment were conducted independently by multiple reviewers (L.H., F.H., L.T.). The primary outcome measures evaluated were gain in clinical attachment level (CAL) and reduction in probing pocket depth (PPD).The search provided 589 abstracts of which six randomized controlled trials were included. Meta-analysis evaluation of these studies indicated that 12 months following treatment, surgical therapy resulted in 0.6 mm more PPD reduction (WMD 0.58 mm; 95% CI 0.38, 0.79) and 0.2 mm more CAL gain (WMD 0.19 mm; 95% CI 0.04, 0.35) than non-surgical therapy in deep pockets (6 mm). In 4-6 mm pockets scaling and root planing resulted in 0.4 mm more attachment gain (WMD -0.37 mm; 95% CI -0.49, -0.26) and 0.4 mm less probing depth reduction (WMD 0.35 mm; 95% CI 0.23, 0.47) than surgical therapy. In shallow pockets (1-3 mm) non-surgical therapy resulted in 0.5 mm less attachment loss (WMD -0.51 mm; 95% CI -0.74, -0.29) than surgical therapy.Both scaling and root planing alone and scaling and root planing combined with flap procedure are effective methods for the treatment of chronic periodontitis in terms of attachment level gain and reduction in gingival inflammation. In the treatment of deep pockets open flap debridement results in greater PPD reduction and clinical attachment gain.

The agricultural/livestock system of a 40,000 km2 area in western Sudan is described. Details of the three main components—traditional rainfed agriculture, small-scale irrigation and animal husbandry—are given. Data on crop yields and livestock production at both the unit level and the system level are provided. Millet is the main cereal crop overall but sorghum occupies an important place in the intensively cultivated alluvial zones. Cash crops, including groundnuts, chillies and okra for drying, are of some importance. Onions are the main winter irrigated crop while mangoes and citrus are important tree crops. The livestock sector is dominated by cattle which account for more than 75% of the livestock units present. Gross output of the area at 1976 prices was calculated at £Sud 14·8 to £Sud 16·2 million (US$ 41·4 to US$ 45·4 million) equivalent to £Sud 41·7 to £Sud 45·6 per head of population and £Sud 3·70 to £Sud 4·05 per hectare. Of these totals between 33 and 36% could be attributed to livestock production.