79 research outputs found

    Propagation of short-period gravity waves at high-latitudes during the MaCWAVE winter campaign

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    As part of the MaCWAVE (Mountain and Convective Waves Ascending Vertically) winter campaign an all-sky monochromatic CCD imager has been used to investigate the properties of short-period mesospheric gravity waves at high northern latitudes. Sequential measurements of several nightglow emissions were made from Esrange, Sweden, during a limited period from 27–31 January 2003. Coincident wind measurements over the altitude range (~80–100 km) using two meteor radar systems located at Esrange and Andenes have been used to perform a novel investigation of the intrinsic properties of five distinct wave events observed during this period. Additional lidar and MSIS model temperature data have been used to investigate their nature (i.e. freely propagating or ducted). Four of these extensive wave events were found to be freely propagating with potential source regions to the north of Scandinavia. No evidence was found for strong orographic forcing by short-period waves in the airglow emission layers. The fifth event was most unusual exhibiting an extensive, but much smaller and variable wavelength pattern that appeared to be embedded in the background wind field. Coincident wind measurements indicated the presence of a strong shear suggesting this event was probably due to a large-scale Kelvin-Helmholtz instability

    Activities of small‐scale gravity waves in the upper mesosphere observed from meteor radar at King Sejong Station, Antarctica (62.22°S, 58.78°W) and their potential sources

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    Gravity wave (GW) activities in the upper mesosphere (80–100 km) and their potential sources are investigated using meteor radar observations at King Sejong Station, Antarctica (KSS; 62.22°S, 58.78°W) during recent 14 years (2007–2020). GW activities are estimated by horizontal wind variances of small-scale GWs (periods <2 h, horizontal wavelength <400 km, or vertical wavelength <3–5 km). The wind variances show clear semiannual variations with maxima at solstices, and annual variations are also seen above z = 90 km. The deseasonalized wind variances at z = 96.8 km have a statistically significant periodicity of ∌11 years that can be associated with solar cycle variations. Three major potential GW sources in the lower atmosphere are examined. Orography is a potential source of GWs in winter and autumn, when the basic-state wind is westerly from the surface up to the mesosphere. The residual of the nonlinear balance equation (RNBE) at 5 hPa, a diagnostic of the GWs associated with jet stream, is the largest in winter and has a secondary maximum in spring. The correlation between the observed GWs and RNBE is significant in equinoxes, while correlation is low in winter. Deep convection in storm tracks is a potential source in autumn and winter. Secondary GWs generated in the mesosphere can also be observed in the upper mesosphere. Ray-tracing analysis for airglow images observed at KSS indicates that secondary GWs are mostly generated in winter mesosphere, which may be associated with the breaking of orographic GWs

    Exploring the views of young women and their healthcare professionals on dietary habits and supplementation practices in adolescent pregnancy: a qualitative study

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    Background: Nutrition is a modifiable factor affecting foetal growth and pregnancy outcomes. Inadequate nutrition is of particular concern in adolescent pregnancies with poor quality diet and competing demands for nutrients. The aim of this study was to explore knowledge and understanding of nutrition advice during adolescent pregnancy,and identify barriers and facilitators to dietary change and supplementation use in this vulnerable population. Methods: Semi-structured interviews were conducted with young women and key antenatal healthcare providers: midwives, family nurses and obstetricians. Doncaster, Manchester and London were chosen as sites offering different models of midwifery care alongside referral to the Family Nurse Partnership programme. Results: A total of 34 young women (adolescents aged 16–19 years) and 20 health professionals were interviewed. Young women made small changes to their dietary intake despite limited knowledge and social constraints. Supplementation use varied; the tablet format was identified by few participants as a barrier but forgetting to take them was the main reason for poor adherence. Health professionals provided nutrition information but often lack the time and resources to tailor this appropriately. Young women’s prime motivator was a desire to have a healthy baby; they wanted to understand the benefits of supplementation and dietary change in those terms. Conclusion: Pregnancy is a window of opportunity for improving nutrition but often constrained by social circumstances. Health professionals should be supported in their role to access education, training and resources which build their self-efficacy to facilitate change in this vulnerable population group beyond the routine care they provide

    An evaluation of the variability of tumor-shape definition derived by experienced observers from CT images of supraglottic carcinomas (ACRIN protocol 6658)

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    Accurate target definition is considered essential for sophisticated, image-guided radiation therapy; however, relatively little information has been reported that measures our ability to identify the precise shape of targets accurately. We decided to assess the manner in which eight “experts” interpreted the size and shape of tumors based on “real life” contrast-enhanced CT scans

    Selective CO₂ capture in metal-organic frameworks with azine-functionalized pores generated by mechanosynthesis

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    Two new three-dimensional porous Zn(II)-based metal-organic frameworks, containing azine-functionalized pores, have been readily and quickly isolated via mechanosynthesis, by using a nonlinear dicarboxylate and linear N-donor ligands. The use of nonfunctionalized and methyl-functionalized N-donor ligands has led to the formation of frameworks with different topologies and metal-ligand connectivities and therefore different pore sizes and accessible volumes. Despite this, both metal-organic frameworks (MOFs) possess comparable BET surface areas and CO₂ uptakes at 273 and 298 K at 1 bar. The network with narrow and interconnected pores in three dimensions shows greater affinity for CO compared to the network with one-dimensional and relatively large pores-attributable to the more effective interactions with the azine groups

    Pilot parallel randomised controlled trial of protective socks against usual care to reduce skin tears in high risk people: 'STOPCUTS'.

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    Skin tears are common in older adults and those taking steroids and warfarin. They are traumatic, often blunt injuries caused by oblique knocks to the extremities. The epidermis may separate from the dermis or both layers from underlying tissues leaving a skin flap or total loss of tissue, which is painful and prone to infection. 'Dermatuffℱ' knee-length socks containing Kevlar fibres (used in stab-proof vests and motorcyclists' clothing) aim to prevent skin tears. The acceptability of the socks and the feasibility of a randomised controlled trial (RCT) had not been explored.Royal Devon & Exeter NHS Foundation TrustThis article is freely available via Open Access. Click on the Additional Link above to access the full-text via the publisher's site.NIHR Research for Patient BenefitEDGE Project ID: 1854

    Managing skin grafts with TNP and Wound Assist Âź

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