Breathing SPACE – a practical approach to the breathless patient.

Breathlessness is a common symptom which may have multiple causes in any one individual and causes which may change over time. Breathlessness campaigns encourage people to see their GP if they are unduly breathless. Members of the London Respiratory Network collaborated to develop a tool which would encourage a holistic approach to breathlessness, which was applicable both at the time of diagnosis and during ongoing management. This has led to the development of the aide memoire “Breathing SPACE” which encompasses 5 key themes – Smoking, Pulmonary disease, Anxiety/psychosocial factors, Cardiac disease and Exercise/fitness. A particular concern was to ensure that high value interventions (smoking cessation and exercise interventions) are prioritised across the life-course and throughout the course of disease management. The approach is relevant both to well people and in those with an underling diagnosis or diagnoses. The inclusion of anxiety draws attention to the importance of mental health issues. Parity of esteem requires the physical health problems of people with mental illness to be addressed. The SPACE mnemonic also addresses the problem of underdiagnosis of heart disease in people with lung disease and vice versa, as well as the systematic undertreatment of these conditions where they do co-occur

Effects of Degree of Particle Melt and Crystallinity in SLS Nylon-12 Parts

Differential Scanning Calorimetry (DSC) traces for SLS Nylon-12 parts display two distinct melt peaks, which have been related to the presence of both melted and crystallised regions, and un-melted particle cores within the part. The relative proportions of each region are defined by the term ‘Degree of Particle Melt’ (DPM), and have a large effect on the mechanical properties of a part. This paper demonstrates that the % crystallinity of SLS Nylon-12 parts is dependent on the DPM. Crucially, research has also shown that the trends for some tensile properties (notably Tensile Strength and Young’s Modulus) change once full melting is complete.Mechanical Engineerin

Road Pricing: The Potential for Comparative Monitoring. A Report to the London Planning Advisory Committee.

This study was designed to review the proposals for road user charging in the Randstad, Stockholm, Oslo and Singapore, to determine the intentions for monitoring of each of these proposed schemes, to assess the implications for the development of policy in London, and to identify any opportunities for obtaining experience which would help in clarifying the uncertainties associated with proposals for road pricing in London. The study reviewed the objectives and operational requirements for road pricing in London and the criticisms levelled against such proposals. On this basis it developed a series of requirements for monitoring and information gathering to help clarify the outstanding uncertainties. These were used as a check list for a series of discussions with those responsible for proposals in the case study cities. Discussions indicated that the proposals in most cities had changed markedly in the period since the study was commissioned. These changes, and the resulting nature of the proposals, meant that only the proposals for Stockholm were sufficiently similar to those in London to justify collaborative monitoring. The report recommends that such collaboration be developed. However, both the Randstad and Oslo schemes offer the opportunity for obtaining information on actual or predicted user response, while the Singapore proposals will provide valuable experience of new technology. It is recommended that all of these are pursued. The discussions highlighted several lessons of direct relevance to the development of policy in London. In particular it is seen as important to keep the specification of the measures simple; to pursue extensive consultation with those who might be affected and with all political parties and government bodies who might be involved in policy decisions; to provide clear guidance on the anticipated uses of the revenue: and to develop a system which is implemented flexibly, so that problems can be remedied as they arise. In this context, the role of assessment and monitoring is limited. It should not be used to delay decisions; however, once a commitment is made to proceed, experience from elsewhere will be of value in informing the consultations. A carefully designed monitoring programme will be important in assessing and enhancing a scheme once implemented. It is recommended that the monitoring programme should be based on the requirements identified in this report

Laser melting functionally graded composition of Waspaloy((R)) and Zirconia powders

An approach for fabricating functionally graded specimens of supernickel alloy and ceramic compositions via Selective Laser Melting (SLM) is presented. The focus aimed at using the Functionally Graded Material (FGM) concept to gradually grade powdered compositions of Zirconia within a base material of Waspaloy® . A high power Nd:YAG laser was used to process the material compositions to a high density with gradual but discrete changes between layered compositions. The graded specimens initially consisted of 100% Waspaloy® with subsequent layers containing increased volume compositions of Zirconia (0-10%). Specimens were examined for porosity and microstructure. It was found that specimens contained an average porosity of 0.34% with a gradual change between layers without any major interface defect

Influence of laser power on tensile properties and material characteristics of laser-sintered UHMWPE

Ultra High Molecular Weight Polyethylene (UHMWPE) has excellent properties, such as high mechanical performance, low friction, high wear and chemical resistance but so far there has been limited use in additive manufacturing (AM). Laser sintering of polymers is one of the most promising AM technologies due to its ability to produce complex geometries with accurate dimensions and good mechanical properties. Consequently, this study investigates the influence of laser power on physical and mechanical properties of UHMWPE parts produced by laser sintering. In particular mechanical properties, such as Ultimate Tensile Strength (UTS), Young’s Modulus and elongation at break were evaluated alongside relative density, dilation and shrinkage. Finally, the fracture surface of the tensile test specimens was examined by electron microscopy. Results show that within a laser power range of 6–12 W there appears to be an optimum where tensile strength and relative density reach a maximum, dilation is minimised and where elongation increases with laser power. UTS up to 2.42 MPa, modulus up to 72.6 MPa and elongation at break up to 51.4% were observed. Relative density and part dimensions are also influenced by laser power

N‐heterocyclic carbene catalyzed photoenolization/Diels–Alder reaction of acid fluorides

The combination of light activation and N‐heterocyclic carbene (NHC) organocatalysis has enabled the use of acid fluorides as substrates in a UVA‐light‐mediated photochemical transformation previously observed only with aromatic aldehydes and ketones. Stoichiometric studies and TD‐DFT calculations support a mechanism involving the photoactivation of an ortho‐toluoyl azolium intermediate, which exhibits “ketone‐like” photochemical reactivity under UVA irradiation. Using this photo‐NHC catalysis approach, a novel photoenolization/Diels–Alder (PEDA) process was developed that leads to diverse isochroman‐1‐one derivatives

On the diffusion of lattice matched InGaAs/InP microstructures

Copyright (2003) American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in F. Bollet et al., J. Appl. Phys. 93, 3881 (2003) and may be found at http://link.aip.org/link/?jap/93/388

Voltage controlled nuclear polarization switching in a single InGaAs quantum dot

Sharp threshold-like transitions between two stable nuclear spin polarizations are observed in optically pumped individual InGaAs self-assembled quantum dots embedded in a Schottky diode when the bias applied to the diode is tuned. The abrupt transitions lead to the switching of the Overhauser field in the dot by up to 3 Tesla. The bias-dependent photoluminescence measurements reveal the importance of the electron-tunneling-assisted nuclear spin pumping. We also find evidence for the resonant LO-phonon-mediated electron co-tunneling, the effect controlled by the applied bias and leading to the reduction of the nuclear spin pumping rate.Comment: 5 pages, 2 figures, submitted to Phys Rev

Fabrication of X-Graded H13 and Cu Powder Mix Using High Power Pulsed Nd:YAG Laser

The manufacturing of Functionally Graded Material (FGM) parts using Solid Free Form manufacturing technologies has been carried out since early 1980. At present, most of the powder manufacturing techniques are being focused on layering powder with different powder blend compositions with Z gradients (graded in direction of layer build). Although, there are a few researchers working on multi powder feeder and deposition system, the study of laser fusion of the deposited powder (by a powder deposition system) is minimum or not known to date. Consequently, the manufacturing of functionally graded structures is still geometry limited. This work was focused on the manufacturing of X-graded (graded along the powder bed plane) specimens with H13 tool steel and Cu mix. Five bimodal powder blends were used with a multi-container feed hopper to spread powder layers for the selective laser fusion of the powder. The powder was fused using a high power Nd:YAG pulsed laser using a specific scanning strategy to reduce porosity. Specimens were produced with graded Cu within the H13 matrix. The specimens were analysed for dimensional accuracy, microstructure, porosity, cracks and micro hardness of the FGM.Mechanical Engineerin

The effect of build orientation and surface modification on mechanical properties of high speed sintered parts

High speed sintering is a novel additive manufacturing technology that uses inkjet printing and infra-red energy to selectively sinter polymeric powder. The research presented here investigates the effect of build orientation on dimensional accuracy, density, mechanical properties and surface roughness of high speed sintered parts. Tensile specimens were built through seven different angles between and including the XY (horizontal) and ZY (vertical) planes and analysed. The effect of the PUSh™ process was also investigated across this range of build orientations. The results show that build orientation does infuence the properties of the parts. A number of mechanical properties showed a relationship with build orientation. Density was seen to decrease as the angle increased from XY towards ZY. This increase in angle was shown to increase surface roughness while ultimate tensile strength and elongation at break decreased. At all build orientations, the PUSh™ process significantly reduces surface roughness, mildly increases part density and had a small effect on ultimate tensile strength whilst showing a small but consistent increase in elongation at break