As indications of ‘overtourism’ appear in the Arctic, tourism presents both management challenges and ethical dilemmas, applicable to broader discussions about sustainability within Polar tourism. I argue that mapping value relations can contribute to ongoing discussions for positive ways forwards and that the concept of degrowth holds promise in redirecting tourism to better serve the local community. Tourism has become the largest employer and most rapidly growing sector in Svalbard, taking over from coal mining. Longyearbyen is a small urban centre but nevertheless is the central hub where almost all tourism passes through. Indeed, tourism is how the majority of human relations with its lands, seas, human and non-human inhabitants will be enabled. This paper is centred on charting the transition of Longyearbyen to a ‘tourist town’. Drawing on local voices from 2013 to 2016 and 2019, I use a value-based analysis to assess the changes experienced in the context of wider systems of value at work in Svalbard.

Marriage during childhood and adolescence adversely affects maternal and child health and well-being, making it a critical global health issue. Analysis of factors associated with women marrying ≥18 years has limited utility in societies where the norm is to marry substantially earlier. This paper investigated how much education Nepali women needed to delay marriage across the range of ages from 15 to ≥18 years. Data on 6,406 women aged 23-30 years were analysed from the Low Birth Weight South Asia Trial on the early-marrying and low-educated Maithili-speaking Madhesi population in Terai, Nepal. Multivariable logistic regression models assessed the associations of women’s education with marrying aged ≥15, ≥16, ≥17 and ≥18 years. Cox proportional hazards regression models quantified the hazard of marrying. Models adjusted for caste affiliation. Women married at median age of 15 years and three-quarters were uneducated. Women’s primary and lower-secondary education were weakly associated with delaying marriage, whether the cut-off to define early marriage was 15, 16, 17 or 18 years, with stronger associations for secondary education. Caste associations were weak. Overall, models explained relatively little of the variance in the likelihood of marriage at different ages. The joint effects of lower-secondary and higher caste affiliation and of secondary/higher education and mid and higher caste affiliation reduced the hazard of marrying. In early-marrying and low-educated societies, changing caste-based norms are unlikely to delay women’s marriage. Research on broader risk factors and norms that are more relevant for delaying marriage in these contexts is needed. Gradual increases in women’s median marriage age and increased secondary education may, over time, reduce child and adolescent marriage.

The work presented here forms part of a larger project on Large-Eddy Simulation (LES) of aeroengine aeroacoustic interactions. In this paper, we concentrate on LES of near-field flow over an isolated NACA0012 aerofoil at zero angle-of-attack and a chord based Reynolds number of Rec = 2 × 105. A wall-resolved compressible Numerical Large Eddy Simulation (NLES) approach is employed to resolve streak-like structures in the near-wall flow regions. The calculated unsteady pressure/velocity field will be imported into an analyticallybased scheme for far-field trailing-edge noise prediction later. The boundary-layer mean and root-mean-square (rms) velocity profiles, the surface pressure fluctuation over the aerofoil, and the wake flow development are compared with experimental data and previous computational simulations in our research group. It is found that the results from the wall-resolved compressible NLES are very encouraging as they correlate well with test data. The main features of the wall-resolved compressible NLES, as well as the advantages of such compressible NLES over previous incompressible LES performed in our research group, are also discussed.

A numerical study of drag reduction by mini-belts in a smooth wall turbulent boundary layer is carried using a second-moment closure turbulence model. The main objective of this exploratory work is to investigate the possibility of using mini-belts, driven by frictional drag only, to reduce the drag of a smooth wall. The results clearly show that such technique can be an effective and cheap means for achieving drag reduction. Furthermore, it is observed that, in contrast to riblets, the use of mini-belts does not suffer from geometrical or size constraints in the context of drag reduction. Also mini-belts will always reduce the skin friction regardless of the flow regime (laminar, transitional and turbulent). These advantages may quite well balance the major difficulty related to their mounting in practical situations

Hot gas ingestion (HGI) can be a problematic feature of short take-off vertical landing (STOVL) aircraft during the descent phase of landing, or while on the ground. The hot exhaust gases from the downwards pointing nozzles can be re-ingested into the engine intakes, causing power degradation or reduced engine surge margin. The flow-fields that characterise this phenomenon are complex, with supersonic impinging jets and cross-flows creating large ground vortices and fountain up-wash flows.

A flow solver has been developed to include a suitable linear mesh deformation technique for the descending aircraft configuration. The code has been applied to predict the occurrence of HGI, by simulating experimental results from a 1/15th scale model of a descending Harrier. This has enabled an understanding of the aerodynamic mechanisms that govern HGI, in terms of the near-field and far-field effects and their impact on the magnitude of temperatures at the engine intake.

This paper presents three sets of CFD results. First a validation exercise shows predicted results from the twin-jet with intake in crossflow test-case. This is an unsteady Reynolds averaged Navier Stokes (URANS) solution for a static geometry (there is no moving mesh). This allows comparison with experiment. Secondly, a full descent phase URANS Spalart-Allmaras (SA) turbulence model calculation is done on an 8·5m cell mesh for half the flow domain of the Harrier model and test-rig without dams/strakes. This shows how the HGI flow mechanisms affect the engine intake temperature profiles, for the case where there are no flow control methods on the underside of the aircraft. Thirdly, the full descent phase URANS SA turbulence model calculation is done on a 22·4m cell mesh for the full flow domain of the Harrier model and test-rig, with the dam/strake geometry included in the structured mesh region.

Toxoplasma gondii and Bartonella spp. are zoonotic pathogens of cats. Feline immunodeficiency virus (FIV), and feline leukaemia virus (FeLV) are immunosuppressive viruses of cats that can affect T. gondii oocyst shedding. In this study, the prevalence of antibodies to T. gondii, Bartonella spp., FIV, as well as FeLV antigens were determined in sera from feral cats (Felis catus) from Addis Ababa, Ethiopia. Using the modified agglutination test, IgG antibodies to T. gondii were found in 41 (85·4%) of the 48 cats with titres of 1:25 in one, 1:50 in one, 1:200 in six, 1:400 in six, 1:800 in six, 1:1600 in eight, and 1:3200 in 13 cats. Toxoplasma gondii IgM antibodies were found in 11/46 cats tested by ELISA, suggesting recent infection. Antibodies to Bartonella spp. were found in five (11%) of 46 cats tested. Antibodies to FIV or FeLV antigen were not detected in any of the 41 cats tested. The results indicate a high prevalence of T. gondii and a low prevalence of Bartonella spp. infection in cats in Ethiopia.

The objective of this study was to develop a basic variety selection decision support system (DSS) based on industry legalities, varietal characteristics and structured genotype-by-environment (G × E) analyses. Trial data extracted from a variety trial database at the South African Sugarcane Research Institute (SASRI) were categorized into different regions, harvest ages (12, 18, 24 months) and harvest seasons (early, mid, late season harvests). Restricted maximum likelihood analyses were conducted regionally to determine varietal adaptability to different harvest ages and seasons. Highly significant variety × harvest age and variety × season interactions allowed for the appropriate categorization of varieties. Varietal adaptability to different yield potential conditions was determined using the sites regression technique, and varietal adaptability was interpreted from the slope of the regression curves. The analysed data were used to create simplistic ‘yes/no’ spreadsheets, which were housed within a relational database. A web interface linked to the database allows users to specify characteristics of their production environment. The system then selects appropriate varieties that conform to specified criteria and eliminates non-compliers in a stepwise approach. The system was subsequently validated against expert extension specialist opinion and acceptable performance was observed.

In New Zealand human cryptosporidiosis demonstrates spring and autumn peaks of incidence with the spring peak being three times greater in magnitude than the autumn peak. The imbalance between the two peaks is notable, and may be associated with the high livestock density in New Zealand. In the summer and autumn the cryptosporidiosis rate was positively associated with temperatures in the current and previous month, highlighting the importance of outdoor recreation to transmission. No associations between spring incidence and weather were found providing little support for the importance of drinking-water pathways. Imported travel cases do not appear to be an important factor in the aetiology of cryptosporidiosis in New Zealand.

A pattern recognition technique has been applied to simultaneously sampled multipoint hot-wire anemometry data obtained in the far wake of a circular cylinder. Data from both the streamwise fluctuating velocity field and the temperature field have been analysed employing a computer code that uses a correlation approach to automatically detect and ensemble average flow patterns and patterns for mean-square fluctuations. Statistical tests then allow the significance and contribution to the turbulence intensity of the detected structures to be evaluated. This procedure has been used to infer the three-dimensional topology of the double-roller eddies previously identified in the far-wake region and to relate these to the motions responsible for entrainment. It appears that the two types of motion are not independent, but are linked together, forming parts of horseshoe vortex structures which account for at least 40% of the total turbulence energy. These structures originate near the centre of the flow, may extend across the centreline and typically occur in groups of about three. The resulting picture of the flow dynamics is related to the conclusions drawn from similar data by other workers and a possible regeneration mechanism is presented. The addition to the code of a fine-scale activity indicator, the choice of which is discussed in some detail, has allowed the relationship between these energetic large-scale motions and smaller eddies to be investigated. It seems that the most intense fine-scale activity is associated with the vortical cores of the double-roller eddies. It is shown that this observation is consistent with the concepts of ‘isotropy’ and ‘spotiness’ of the dissipative scales. It also suggests that the horseshoe vortices loose energy both to their own secondary instabilities and to smaller scales resulting from the breakup of other highly strained large eddies.

Parametric studies have been made of devices introduced into the outer region of a low-Reynolds-number turbulent boundary layer (Reθ = 1000-3500) with a view to understanding the manner in which such ‘manipulators’ reduce the surface drag. The devices considered were single flat plates, a cylinder with the same drag as one of these, and two plates stacked, staggered, and in tandem, with chord Reynolds numbers Rec in the range 1000-100000. Direct measurements of local skin friction using a floating-plate drag balance are reported together with the results of laser- sheet smoke flow visualization. The skin-friction results are in good agreement with other floating-element data while the visual and photographic studies in both stationary and convected frames completely support the hairpin description of the boundary-layer structure, and reveal that the wake of the device may play a more important role than has previously been suggested. A picture is presented of the interaction of the devices and their wakes with the hairpin eddy structure which could explain the magnitudes and shapes of the skin-friction distributions observed downstream; their dependence on the height, thickness, and if appropriate, length and spacing of the device(s); the optimum values for these parameters; and the existence of a preferred, tandem plate configuration. The results suggest that such plates do not act primarily as large-eddy break-up systems (LEBUs). Instead several ‘active’ mechanisms are identified which supplement the ‘passive’ effect of the imposed momentum defect. The suppression of large-scale motions is one of these, but, a t least for our relatively thick devices, it would appear that it is an interaction between the vortices, introduced into the layer via the wake, and the near-wall structure that provides the principal mechanism for reducing the skin friction. The observation that the maximum skin-friction reduction always occurred close to the position where these vortices reached the sublayer provides strong evidence for such a view.