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Noise from a tactical aircraft can impact operations due to concerns regarding military personnel noise exposure and community annoyance and disturbance. The efficacy of mission planning can increase when the distinct, complex acoustic source mechanisms creating the noise are better understood. For each type of noise, equivalent acoustic source distributions are obtained from a tied-down F-35B operating at various engine conditions using the hybrid method for acoustic source imaging of Padois, Gauthier, and Berry [J. Sound Vib. 333, 6858-6868 (2014)]. The source distributions for the distinct noise types are obtained using different sections of a 71 element, ground-based linear array. Using a subarray close to the nozzle exit plane, source distributions are obtained for fine-scale turbulent mixing noise and broadband shock-associated noise, although grating lobes complicate interpretations at higher frequencies. Results for a subarray spanning the maximum sound region show that the multiple frequency peaks in tactical aircraft noise appear to originate from overlapping source regions. The observation of overlapping spatial extent of competing noise sources is supported by the coherence properties of the source distributions for the different subarrays.

Radiolytic corrosion of actinide materials represent an issue for the long term storage and disposal of nuclear materials. Molecular species adsorbed at the surface of the actinides may impact the rate of radiolysis, and as the surfaces corrode, the soluble toxic and radioactive species leach into groundwater. It is therefore critical to characterise the surface composition of actinides. Here, we employ ab initio modelling to determine the surface composition of PuO2 with respect to adsorbed CO2. We found that CO2 interacts strongly with the surface forming carbonate species. By mapping the energetics of this interaction, we then calculate the temperature of desorption, finding that surface morphology has a strong impact on the adsorption of CO2, with the {100} being the most and the {111} the least affected by carbonation. Finally, we predict the effect of carbonation on the morphology of PuO2 nanoparticles as a function of temperature and pressure, finding that truncated octahedral is the preferred morphology. This modelling strategy helps characterise surface compensition and nanoparticle morphology, and we discuss the implication for radiolytically driven dispersal of material into the environment.

This paper reports experiments investigating the reaction of H$_{2}$ with uranium metal-oxide bilayers. The bilayers consist of $\leq$ 100 nm of epitaxial $\alpha$-U (grown on a Nb buffer deposited on sapphire) with a UO$_{2}$ overlayer of thicknesses of between 20 and 80 nm. The oxides were made either by depositing via reactive magnetron sputtering, or allowing the uranium metal to oxidise in air at room temperature. The bilayers were exposed to hydrogen, with sample temperatures between 80 and 200 C, and monitored via in-situ x-ray diffraction and complimentary experiments conducted using Scanning Transmission Electron Microscopy - Electron Energy Loss Spectroscopy (STEM-EELS). Small partial pressures of H$_{2}$ caused rapid consumption of the U metal and lead to changes in the intensity and position of the diffraction peaks from both the UO$_{2}$ overlayers and the U metal. There is an orientational dependence in the rate of U consumption. From changes in the lattice parameter we deduce that hydrogen enters both the oxide and metal layers, contracting the oxide and expanding the metal. The air-grown oxide overlayers appear to hinder the H$_{2}$-reaction up to a threshold dose, but then on heating from 80 to 140 C the consumption is more rapid than for the as-deposited overlayers. STEM-EELS establishes that the U-hydride layer lies at the oxide-metal interface, and that the initial formation is at defects or grain boundaries, and involves the formation of amorphous and/or nanocrystalline UH$_{3}$. This explains why no diffraction peaks from UH$_{3}$ are observed. {\textcopyright British Crown Owned Copyright 2017/AWE}, Comment: Submitted for peer review

A method is presented to suppress grating lobes in beamforming using phase unwrapping and array interpolation. When the phase of each cross spectrum is successfully unwrapped, the magnitude and phase of the cross spectral matrix may be interpolated; for cases where these quantities vary smoothly, interpolation is straightforward, even above the spatial Nyquist frequency. Two applications are presented: localization of a broadband source and characterization of a source with frequency-dependent location. In both cases, grating lobes are suppressed and the source is localized at frequencies up to at least 8 times the spatial Nyquist frequency.

Meaningful use of the autocorrelation in jet noise analysis is examined. The effect of peak frequency on the autocorrelation function width is removed through a temporal scaling prior to making comparisons between measurements or drawing conclusions about source characteristics. In addition, a Hilbert transform-based autocorrelation envelope helps to define consistent characteristic time scales. Application of these processes to correlation functions based on large and fine-scale similarity spectra reveal that the large-scale noise radiation from an F-22A deviates from the similarity spectrum model.

In skin care, the axilla is a biologically unique site requiring specialized attention and care. This area of skin is often subject to hair removal techniques, such as shaving and plucking. These procedures damage the skin leading to erythema and dryness in the short term, and in some cases, post-inflammatory hyperpigmentation (PIHP) in the long term. This study will (i) briefly review the biology and unique properties of axillary skin, and (ii) describe the characteristics of the irritation and damage induced by contemporary skin care habits and resolution of these responses by the use of efficacious skin moisturizing technology. With respect to the latter, we propose that there are five groups of compounds, defined according to their mechanism of action, which are particularly relevant to the care of damaged axillary skin.

The bending stiffness in a homogeneous, isotropic, thin plate is experimentally derived from measurements of coincidence angles extracted from supercritical sound transmission versus frequency measurements. A computer controlled turn table rotates a plate sample and a receiver array, placed in the near field of the plate. The array is used to track the transmitted sound through the plate, generated by a far-field stationary source, using beam forming. The array technique enables measurement of plates measuring only one wavelength in width. Two examples are used for proof of concept, including an aluminum plate in air and an alumina plate under water.

This article illustrates the creation of a specialty specific portfolio that can be used by several different residency programs to document resident competence during a given rotation.Three different disciplines (anesthesiology, surgery and medicine) worked together to create a critical care medicine portfolio. We began by reviewing the curriculum requirements for critical care medicine and organized these requirements into the six ACGME core competencies. We then developed learner led exercises in each core competency that were specific to critical care. Each exercise includes assessment of resident knowledge and application, an evaluation of the exercise, a learner self-assessment of skill, and a review of performance by a faculty member. Portfolio entries are highlighted in a multi-disciplinary weekly conference and posted on a critical care web site at our University.Creation of specialty specific portfolio reduces redundancy between disciplines, allows for increased time to be spent on the development of exercises specific to rotation objectives, and aids program directors in the collection of portfolio entries for each resident over the course of a residency.

The influence of oxygen-grown UO 2+ x films on the early (induction, acceleration) stages of the massive uranium–hydrogen reaction has been studied in a non-visual, constant-volume cell. The potential for (i) adsorbed small molecules (e.g., H 2 O) impeding the reaction and (ii) unintended oxide fracture has been reduced. Induction times were determined by pressure fall, while reaction site nucleation rates were determined by post-reaction visual analysis. Oxidation data from this work suggests that under these conditions the reaction exhibits break-away behaviour at ∼6 μg O 2 cm −2 (calculated mean oxide thickness ∼500 A). Hydriding results indicate that the induction time is related to the mean oxide thickness and increases with increase of oxygen consumption up to at least 25 μg O 2 cm −2 (calculated mean oxide thickness ∼2000 A). However, the hydriding induction time, unexpectedly, does not appear to plateau or reduce as the consumption exceeds 6 μg O 2 cm −2 . Results also indicate that, for any given oxide film, the nucleation rate, as calculated from post-reaction visual analysis, increases with exposure time to hydrogen. Also in general, for a fixed consumption of hydrogen per unit area, the thinnest oxide films result in more reaction sites and a higher mean nucleation rate. Conversely, the thickest oxide films result in fewer reaction sites and a lower mean nucleation rate. In a similar manner to the induction time results, the reaction site nucleation rate is influenced by the degree of prior oxidation, both pre- and post-break-away.

This article highlights work underway in three English local authorities to promote effective inter-agency collaboration around the education of looked after children. Insight drawn from these local authorities is used to review previous literature concerning inter-agency collaboration in a variety of contexts. The relevance of previous research to issues concerning the education of looked after children is discussed and key factors associated with effective collaboration are highlighted. Barriers which have served to obstruct joint working and strategies adopted to deal with these are also discussed.

This paper documents the views of a sample of 80 children and young people, aged 10–18 years, living in foster and residential care placements in England, regarding their educational experience whilst being looked after. The children were interviewed as part of an ongoing evaluation of the Taking Care of Education project, a development programme designed to facilitate improvements in the education of looked after children, co-ordinated by the National Children's Bureau and funded by the Gatsby Charitable Foundation. Interviews with the sample asked children to assess their current educational progress and identify individuals who supported or hindered their education, as well as the availability of educational support in care placements. Teaching staff were frequently mentioned as providers of support, whilst social workers were often associated with hindering educational progress. Children and young people had access to a range of educational supports in care placements, and these were more widely available in residential settings than in foster care. Children offered a range of pertinent suggestions as to how the educational experience of those in the public care system might be improved.

Objectives: This study measured the extent to which a systematic approach was used to select criteria for audit, and identified problems in using such an approach with potential solutions. Design: A questionnaire survey using the Audit Criteria Questionnaire (ACQ), created, piloted, and validated for the purpose. Possible ACQ scores ranged from 0 to 1, indicating how systematically the criteria had been selected and how usable they were. Setting: A stratified random sample of 10 audit leads in each of 83 randomly selected NHS trusts and all practices in each of 11 randomly selected primary care audit group areas in England and Wales. Participants: Audit leads of ongoing audits in each organisation in which a first data collection had started less than 12 months earlier and a second data collection was not completed. Main outcome measures: ACQ scores, problems identified in the audit criteria selection process, and solutions found. Results: The mean ACQ score from all 83 NHS trusts and the 11 primary care audit groups was 0.52 (range 0.0–0.98). There was no difference between mean ACQ scores for criteria used in audits on clinical (0.51) and non-clinical (0.52) topics. The mean ACQ scores from nationally organised audits (0.59, n=33) was higher than for regional (0.51, n=21), local (0.53, n=77), or individual organisation (0.52, n=335) audits. The mean ACQ score for published audit protocols (0.56) was higher than for locally developed audits (0.49). There was no difference in ACQ scores for audits reported by general practices (0.49, n=83) or NHS trusts (0.53, n=383). Problems in criteria selection included difficulties in coordination of staff to undertake the task, lack of evidence, poor access to literature, poor access to high quality data, lack of time, and lack of motivation. Potential solutions include investment in training, protected time, improved access to literature, support staff and availability of published protocols. Conclusions: Methods of selecting review criteria were often less systematic than is desirable. Published usable audit protocols providing evidence based review criteria with information on their provenance enable appropriate review criteria to be selected, so that changes in practice based on these criteria lead to real improvement in quality rather than merely change. The availability and use of high quality audit protocols would be a valuable contribution to the evolution of clinical governance. The ACQ should be developed into a tool to help in selecting appropriate criteria to increase the effectiveness of audit.

Silver carboxylates [Ag(O2CR): R=Me, tBu, 2,4,6-Me3C6H2], fluorocarboxlyates [Ag(O2CRf): Rf=C3F7, C6F13, C7F15] and their phosphine adducts [Ag(O2CR)·nPR3′: R=Me, tBu, 2,4,6-Me3C6H2, R′=Me, Ph, n=2; R=Me, R′=Me, n=3; Ag(O2CRf).2PPh3, Rf=C3F7, C6F13, C7F15] have been synthesised, characterised spectroscopically and used as precursors in the aerosol-assisted chemical vapour deposition of silver films. All the phosphine adducts produced films, though in general PMe3 adducts, proved more successful than PPh3 analogues. The fluoro-carboxylates and their PPh3 adducts all generated silver films, though the growth rate for the adducts was lower. All these latter films showed carbon impurities while fluorine was also evident in most cases. The X-ray structure of AgO2CC3F7·2PPh3 is also reported.

Triphenylphosphine adducts of silver β-diketonates [AgL(PPh 3 )] (L=acac, dpm, tfac, hfac, fod) and β-ketoiminates (L=hfacNhex, hfacNchex) have been synthesised and evaluated as precursors for the deposition of silver films using aerosol-assisted chemical vapour deposition methodology. The 1:1 stoichiometry of the adducts has been established by 31 P and 109 Ag NMR and a crystal structure of [Ag(hfac)(PPh 3 )]. The best films were obtained from the two β-ketoiminates, particularly L=hfacNhex. While [AgL(PPh 3 )] (L=acac, dpm) gave almost no deposition, the complex with L=tfac gave a film comparable with the two β-ketoiminates while other films showed poor reflectivity (L=hfac, fod).

Time reversal (TR) utilizes an array of transducers, a time reversal mirror (TRM), to locate sources. Here TR is applied to simple sources using steady-state waveforms in a numerical, point source model in a half-space environment. It is found that TR can effectively localize a simple source broadcasting a continuous wave, depending on the angular spacing. Furthermore, the angular spacing and the aperture of the TRM are the most important parameters when creating a setup of receivers for imaging a source. This work optimizes a TRM when the source's location is known within a region of certainty.

The creation of families by means of the new reproductive technologies has raised important questions about the consequences for parent-child relationships, particularly where gamete donation has been used to conceive the child. Preliminary findings are presented of a study of the quality of parenting in families created as a result of the two most widely used reproductive technologies, in vitro fertilization and donor insemination, in comparison with a control group of families with a naturally conceived child and a control group of adoptive families. The quality of parenting was assessed using a standardized interview with the mother, and mothers and fathers completed questionnaire measures of stress associated with parenting. The results showed that the quality of parenting in families with a child conceived by assisted conception is superior to that shown by families with a naturally conceived child. The findings are discussed in terms of their implications for understanding the role of genetic ties in parent-child relationships.