1,030 research outputs found
How can universities ‘ASSIST’ student midwives with additional needs to achieve?
Previous articles have discussed how pre-registration midwifery education should prepare student midwives ‘to cope with the complex emotional and physical demands of their chosen profession’ (Power, 2016a:66); acknowledged the importance of a partnership approach to education through the ‘Clinicians in the Classroom’ series (Power, 2016b; Power and Rea, 2016; Power and Rooth, 2016; Power and Gupta, 2016; Power and Briody, 2016) and considered how best to support student midwives with appropriate learning and teaching strategies (Power and Farmer, 2017). What is yet to be considered is what extra support is available to students who have additional needs, disabilities or medical conditions that might impact on their studies. This article will take the University of Northampton as a case study and review the support services it has in place to support such students to meet their full potential. This service is called The Additional Student Support and Inclusion Services Team (ASSIST)
Precise, contactless measurements of the surface tension of picolitre aerosol droplets
The surface composition and surface tension of aqueous droplets can influence key aerosol characteristics and processes including the critical supersaturation required for activation to form cloud droplets in the atmosphere. Despite its fundamental importance, surface tension measurements on droplets represent a considerable challenge owing to their small volumes. In this work, we utilize holographic optical tweezers to study the damped surface oscillations of a suspended droplet (<10 μm radius) following the controlled coalescence of a pair of droplets and report the first contactless measurements of the surface tension and viscosity of droplets containing only 1–4 pL of material. An advantage of performing the measurement in aerosol is that supersaturated solute states (common in atmospheric aerosol) may be accessed. For pairs of droplets starting at their equilibrium surface composition, surface tensions and viscosities are consistent with bulk equilibrium values, indicating that droplet surfaces respond to changes in surface area on microsecond timescales and suggesting that equilibrium values can be assumed for growing atmospheric droplets. Furthermore, droplet surfaces are shown to be rapidly modified by trace species thereby altering their surface tension. This equilibration of droplet surface tension to the local environmental conditions is illustrated for unknown contaminants in laboratory air and also for droplets exposed to gas passing through a water–ethanol solution. This approach enables precise measurements of surface tension and viscosity over long time periods, properties that currently are poorly constrained
Peripheral Blood Mononuclear Cells Enhance Cartilage Repair in in vivo Osteochondral Defect Model.
This study characterized peripheral blood mononuclear cells (PBMC) in terms of their potential in cartilage repair and investigated their ability to improve the healing in a pre-clinical large animal model. Human PBMCs were isolated with gradient centrifugation and adherent PBMC's were evaluated for their ability to differentiate into adipogenic, chondrogenic and osteogenic lineages and also for their expression of musculoskeletal genes. The phenotype of the PBMCs was evaluated using Stro-1, CD34, CD44, CD45, CD90, CD106, CD105, CD146 and CD166 cell surface markers. Osteochondral defects were created in the medial femoral condyle (MFC) of 24 Welsh mountain sheep and evaluated at a six month time point. Four cell treatment groups were evaluated in combination with collagen-GAG-scaffold: (1) MSC alone; (2) MSCs and PBMCs at a ratio of 20:1; (3) MSCs and PBMC at a ratio of 2:1 and (4) PBMCs alone. Samples from the surgical site were evaluated for mechanical properties, ICRS score and histological repair. Fresh PBMC samples were 90% positive for hematopoietic cell surface markers and negative for the MSC antibody panel (<1%, p = 0.006). However, the adherent PBMC population expressed mesenchymal stem cell markers in hypoxic culture and lacked CD34/45 positive cells (<0.2%). This finding demonstrated that the adherent cells had acquired an MSC-like phenotype and transformed in hypoxia from their original hematopoietic lineage. Four key genes in muskuloskeletal biology were significantly upregulated in adherent PBMCs by hypoxia: BMP2 4.2-fold (p = 0.0007), BMP6 10.7-fold (p = 0.0004), GDF5 2.0-fold (p = 0.002) and COL1 5.0-fold (p = 0.046). The monolayer multilineage analysis confirmed the trilineage mesenchymal potential of the adherent PBMCs. PBMC cell therapy was equally good as bone marrow MSC therapy for defects in the ovine large animal model. Our results show that PBMCs support cartilage healing and oxygen tension of the environment was found to have a key effect on the derivation of a novel adherent cell population with an MSC-like phenotype. This study presents a novel and easily attainable point-of-care cell therapy with PBMCs to treat osteochondral defects in the knee avoiding any cell manipulations outside the surgical room.PhD studentship for Niina Hopper was from charitable trust John Insall Foundation US. Dr. John Wardale acknowledges funding from the Technology Strategy Board and industrial partner OrthoMimetics (currently known as Tigenix) and Dr. Roger Brooks acknowledges funding from the National Institute for Health Research for their salaries.This is the final version of the article. It first appeared from PLOS via http://dx.doi.org/10.1371/journal.pone.013393
Reduction in predicted survival times in cold water due to wind and waves
Recent marine accidents have called into question the level of protection provided by immersion suits in real (harsh) life situations. Two immersion suit studies, one dry and the other with 500mL of water underneath the suit, were conducted in cold water with 10-12 males in each to test body heat loss under three environmental conditions: calm, as mandated for immersion suit certification, and two combinations of wind plus waves to simulate conditions typically found offshore. In both studies mean skin heat loss was higher in wind and waves vs. calm; deep body temperature and oxygen consumption were not different. Mean survival time predictions exceeded 36h for all conditions in the first study but were markedly less in the second in both calm and wind and waves. Immersion suit protection and consequential predicted survival times under realistic environmental conditions and with leakage are reduced relative to calm conditions.Peer reviewed: YesNRC publication: Ye
Research and Practice in Voice Studies: Searching for a Methodology
As more and more actor training conservatoires become subsumed into university structures there is a growing pressure on practice based teachers of voice to become active researchers. At the same time there is a growing area of scholarly research within Voice Studies. This article examines the shifting patterns of research and practice within Voice Studies and uses, as a case study, the author’s experiences of teaching at the Royal Central School of Speech and Drama (RCSSD). The author examines tensions between practice and research within a conservatoire setting and explores potential research methodologies in relation to this. The author proposes Practice as Research (PaR) as a suitable methodology for research within practice based Voice Studies and draws on current discourses relating to PaR within Theatre and Performance. The author proposes a model for Voice Studies PaR, which is based on the work of Robin Nelson, and demonstrates how this is being applied within Voice Studies research at RCSSD. The author addresses issues of dissemination of PaR and briefly relates the work in the UK to growing research agendas internationally
Evaluation of denoising strategies to address motion-correlated artifacts in resting-state functional magnetic resonance imaging data from the human connectome roject
Like all resting-state functional connectivity data, the data from the Human Connectome Project (HCP) are adversely affected by structured noise artifacts arising from head motion and physiological processes. Functional connectivity estimates (Pearson's correlation coefficients) were inflated for high-motion time points and for high-motion participants. This inflation occurred across the brain, suggesting the presence of globally distributed artifacts. The degree of inflation was further increased for connections between nearby regions compared with distant regions, suggesting the presence of distance-dependent spatially specific artifacts. We evaluated several denoising methods: censoring high-motion time points, motion regression, the FMRIB independent component analysis-based X-noiseifier (FIX), and mean grayordinate time series regression (MGTR; as a proxy for global signal regression). The results suggest that FIX denoising reduced both types of artifacts, but left substantial global artifacts behind. MGTR significantly reduced global artifacts, but left substantial spatially specific artifacts behind. Censoring high-motion time points resulted in a small reduction of distance-dependent and global artifacts, eliminating neither type. All denoising strategies left differences between high- and low-motion participants, but only MGTR substantially reduced those differences. Ultimately, functional connectivity estimates from HCP data showed spatially specific and globally distributed artifacts, and the most effective approach to address both types of motion-correlated artifacts was a combination of FIX and MGTR
Effect of crystallization kinetics on the properties of spray dried microparticles
A droplet chain technique was used to study the influence of the crystallization process on the morphology of spray dried microparticles. A piezoceramic dispenser produced a chain of monodisperse solution droplets with an initial diameter in the range of 60–80 µm. Aqueous solutions of sodium nitrate were prepared in concentrations ranging from 5 mg/ml to 5⋅10−5 mg/ml. The solution droplets were injected into a laminar flow with gas temperatures varying from 25 to 150°C, affecting the droplet temperature and the evaporation rate, accordingly. Dried particles with diameters between 0.3 and 18 µm were collected. The properties of the collected microparticles were studied and correlated with a particle formation model which predicted the onset of saturation and crystallization. The model accounted for the dependence of the diffusion coefficient of sodium nitrate in water on droplet viscosity. The viscosity trend for sodium nitrate solutions was determined by studying the relaxation time observed during coalescence of two aqueous sodium nitrate droplets levitated in optical tweezers. The combination of theoretical derivations and experimental results showed that longer time available for crystallization correlates with larger crystal size and higher degrees of crystallinity in the final microparticles
Degradation of the plant defense signal salicylic acid protects Ralstonia solanacearum from toxicity and enhances virulence on tobacco
Plants use the signaling molecule salicylic acid (SA) to trigger defenses against diverse pathogens, including the bacterial wilt pathogen Ralstonia solanacearum. SA can also inhibit microbial growth. Most sequenced strains of the heterogeneous R. solanacearum species complex can degrade SA via gentisic acid to pyruvate and fumarate. R. solanacearum strain GMI1000 expresses this SA degradation pathway during tomato pathogenesis. Transcriptional analysis revealed that subinhibitory SA levels induced expression of the SA degradation pathway, toxin efflux pumps, and some general stress responses. Interestingly, SA treatment repressed expression of virulence factors, including the type III secretion system, suggesting that this pathogen may suppress virulence functions when stressed. A GMI1000 mutant lacking SA degradation activity was much more susceptible to SA toxicity but retained the wild-type colonization ability and virulence on tomato. This may be because SA is less important than gentisic acid in tomato defense signaling. However, another host, tobacco, responds strongly to SA. To test the hypothesis that SA degradation contributes to virulence on tobacco, we measured the effect of adding this pathway to the tobacco-pathogenic R. solanacearum strain K60, which lacks SA degradation genes. Ectopic addition of the GMI1000 SA degradation locus, including adjacent genes encoding two porins and a LysR-type transcriptional regulator, significantly increased the virulence of strain K60 on tobacco. Together, these results suggest that R. solanacearum degrades plant SA to protect itself from inhibitory levels of this compound and also to enhance its virulence on plant hosts like tobacco that use SA as a defense signal molecule. (Résumé d'auteur
Galactic halo cusp-core: tidal compression in mergers
We explain in simple terms how the buildup of dark haloes by merging compact
satellites, as in the CDM cosmology, inevitably leads to an inner cusp of
density profile with \alpha \gsim 1, as seen in
cosmological N-body simulations. A flatter halo core with exerts on
the satellites tidal compression in all directions, which prevents deposit of
stripped satellite material in the core region. This makes the satellite orbits
decay from the radius where to the halo centre with no local
tidal mass transfer and thus causes a rapid steepening of the inner profile to
. These tidal effects, the resultant steepening of the profile to a
cusp, and the stability of this cusp to tandem mergers with compact satellites,
are demonstrated using N-body simulations. The transition at is
then addressed using toy models in the limiting cases of impulse and adiabatic
approximations and using tidal radii for satellites on radial and circular
orbits. In an associated paper we address the subsequent slow convergence from
either side to an asymptotic stable cusp with \alpha \gsim 1. Our analysis
thus implies that an inner cusp is enforced when small haloes are typically
more compact than larger haloes, as in the CDM scenario, such that enough
satellite material makes it intact into the inner halo and is deposited there.
We conclude that a necessary condition for maintaining a flat core, as
indicated by observations, is that the inner regions of the CDM satellite
haloes be puffed up by about 50% such that when they merge into a bigger halo
they would be disrupted outside the halo core. This puffing up could be due to
baryonic feedback processes in small haloes, which may be stimulated by the
tidal compression in the halo cores.Comment: 19 pages, Latex, mn2e.cls, some revisions, MNRAS in pres
Diffusion and reactivity in ultraviscous aerosol and the correlation with particle viscosity
Direct comparison of diffusion coefficients and viscosities of ternary component single aerosol particles levitated using optical tweezers.</p
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