Ultrasonic Samples Using Diffusion Bonding Techniques

The objective of this part of the ARPA/AFML program was to produce a set of standard samples which would be suitable for NDE testing and characterization of different NDE techniques. The idea was to have a standard set of samples that could be used to compare results of various investigators and various techniques. In addition to internal defects it was decided, that in order to couple the previous work, the standard flat bottom hole type of defect should also be produced and so we have done this

Shear bands and cracking of metallic glass plates in bending

The thickness dependence of yielding and fracture of metallic glass plates subjected to bending is considered in terms of the shear band processes responsible for these properties. We argue that the shear band spacing (and length) scales with the thickness of the plate because of strain relaxation in the vicinity of the shear band at the surface. This is consistent with recent measurements of shear band spacing versus sample size. We also argue that the shear displacements in the shear band scale with the shear band length and plate thickness, thus causing cracks to be initiated in thicker plates at smaller bending strains. This leads to fracture bending strains that decrease markedly with increasing plate thickness, consistent with recent experiments. These results suggest that amorphous metals in the form of foams might have superior ductility and toughness

New Ultrasonic Standards

Standard samples containing defects of known size, shape, and· location are requirements for the evaluation and calibration of NDE test equipment. Here we review the methods developed f~r producing such samples from selected metallic alloys and ceramics. In the work with metallic alloys, the method of diffusion bonding Ti-6Al-4V is presented in some detail and is illustrated for a large number of samples containing a variety of defects ranging from spherical cavities and inclusions, to prolate and oblate spheroids, to thin discs and simulated cracks. In the work with ceramics, the method of hot pressing of glasses with cavities and inclusions is illustrated for a variety of defects. The presentation demonstrates how these samples may be applied in a procedure for calibrating ultrasonic systems by employing a recently proposed characteristic equation for the system and a figure-of-merit for the transducers in analogy to the gain of a radar antenna

Measurements of Ultrasonic Scattering from Bulk Flaws of Complex Shape

The report summarizes the design and early results of scattering experiments on fl aw.s of complex shape. In close collaboration with the varied theoretical groups representing different inversion algorithms, a unique set of diffusion bonded samples have been designed. These samples contain a variety of irregular and multiple flaws whose scattering characteristics will be obtained in order to guide and evaluate developments of theoretical approaches and test specific theoretical predictions. The majority of these samples have been received an.d the measurements have begun. Results on selected samples are presented an.d compared with scattering from ellipsoidal voids. The measurements will include angular, frequency and time domain variations of the scattered signals made possible with a new ultrasonic data acquisition system

Perspectives and ambitions of interdisciplinary connectivity researchers

The article reviews research perspectives and ambitions of connectivity scientists in order to facilitate and improve joint connectivity research efforts across disciplinary boundaries. The assessment of four very different viewpoints (pragmatic, conceptual, epistemological and ontological) on connectivity signifies the diversity of thought and practice in the connectivity community and calls for a structured way to ensure mutual understanding in collaborative settings. The shared mental model approach is introduced with an exploratory case study as a way to overcome persistent barriers in understanding by identifying gaps and overlaps of individual researchers' perspectives and knowledge that should help improve collaboration in this interdisciplinary environment.</p

Quantifying sympathetic neuro-haemodynamic transduction at rest in humans:Insights into sex, ageing and blood pressure control

KEY POINTS: We have developed a simple analytical method for quantifying the transduction of sympathetic activity into vascular tone. This method demonstrates that as women age, the transfer of sympathetic nerve activity into vascular tone is increased, so that for a given level of sympathetic activity there is more vasoconstriction. In men, this measure decreases with age. Test–re‐test analysis demonstrated that the new method is a reliable estimate of sympathetic transduction. We conclude that increased sympathetic vascular coupling contributes to the age‐related increase in blood pressure that occurs in women only. This measure is a reliable estimate of sympathetic transduction in populations with high sympathetic nerve activity. Thus, it will provide information regarding whether treatment targeting the sympathetic nervous system, which interrupts the transfer of sympathetic nerve activity into vascular tone, will be effective in reducing blood pressure in hypertensive patients. This may provide insight into which populations will respond to certain types of anti‐hypertensive medication. ABSTRACT: Sex and age differences in the sympathetic control of resting blood pressure (BP) may be due to differences in the transduction of sympathetic nerve activity (SNA) into vascular tone. Current methods for dynamically quantifying transduction focus on the relationship between SNA and vasoconstriction during a pressor stimulus, which increases BP and may be contra‐indicated in patients. We describe a simple analytical method for quantifying transduction under resting conditions. We performed linear regression analysis of binned muscle SNA burst areas against diastolic BP (DBP). We assessed whether the slope of this relationship reflects the transduction of SNA into DBP. To evaluate this, we investigated whether this measure captures differences in transduction in different populations. Specifically, we (1) quantified transduction in young men (YM), young women (YW), older men (OM) and postmenopausal women (PMW); and (2) measured changes in transduction during β‐blockade using propranolol in YW, YM and PMW. YM had a greater transduction vs. OM (0.10 ± 0.01 mmHg (% s)(−1), n = 23 vs. 0.06 ± 0.01 mmHg (% s)(−1), n = 18; P = 0.003). Transduction was lowest in YW (0.02 ± 0.01 mmHg (% s)(−1), n = 23) and increased during β‐blockade (0.11 ± 0.01 mmHg (% s)(−1); P < 0.001). Transduction in PMW (0.07 ± 0.01 mmHg (% s)(−1), n = 23) was greater compared to YW (P = 0.001), and was not altered during β‐blockade (0.06 ± 0.01 mmHg (% s)(−1); P = 0.98). Importantly, transduction increased in women with age, but decreased in men. Transduction in women intersected that in men at 55 ± 1.5 years. This measure of transduction captures age‐ and sex‐differences in the sympathetic regulation of DBP and may be valuable in quantifying transduction in disease. In particular, this measure may help target treatment strategies in specific hypertensive subpopulations

A chemotactic-based model for spatial activity recognition

Spatial activity recognition in everyday environments is particularly challenging due to noise incorporated during video-tracking. We address the noise issue of spatial recognition with a biologically inspired chemotactic model that is capable of handling noisy data. The model is based on bacterial chemotaxis, a process that allows bacteria to survive by changing motile behaviour in relation to environmental dynamics. Using chemotactic principles, we propose the chemotactic model and evaluate its classification performance in a smart house environment. The model exhibits high classification accuracy (99%) with a diverse 10 class activity dataset and outperforms the discrete hidden Markov model (HMM). High accuracy (&gt;89%) is also maintained across small training sets and through incorporation of varying degrees of artificial noise into testing sequences. Importantly, unlike other bottom&ndash;up spatial activity recognition models, we show that the chemotactic model is capable of recognizing simple interwoven activities

Update of the European paediatric respiratory medicine syllabus

The 10-year-old European syllabus for paediatric respiratory medicine (PRM; also known as paediatric pulmonology) was updated by a consensus-based method using an expert task force for redrafting, and a subsequent Delphi process to achieve consensus. There was a high degree of consensus for the final syllabus, which has been streamlined and made more relevant to current practice. All modules are now mandatory apart from the undertaking of research projects, which is optional. Although there are still a number of countries in Europe which do not recognise PRM as a separate subspecialty, there are paediatric respiratory physicians practising in every country in Europe, and a current and harmonised European syllabus in the subspecialty remains important for defining the training and areas of practice of PRM practitioners

Implementation and adoption of nationwide electronic health records in secondary care in England: Final qualitative results from prospective national evaluation in "early adopter" hospitals

This is an open-access article distributed under the terms of the Creative Commons Attribution Non-commercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/2.0/ and http://creativecommons.org/licenses/by-nc/2.0/legalcode.Objectives: To evaluate the implementation and adoption of the NHS detailed care records service in “early adopter” hospitals in England. Design: Theoretically informed, longitudinal qualitative evaluation based on case studies. Setting: 12 “early adopter” NHS acute hospitals and specialist caresettings studied over two and a half years. Data sources: Data were collected through in depth interviews, observations, and relevant documents relating directly to case study sites and to wider national developments that were perceived to impact on the implementation strategy. Data were thematically analysed, initially within and then across cases. The dataset consisted of 431 semistructured interviews with key stakeholders, including hospital staff, developers, and governmental stakeholders; 590 hours of observations of strategic meetings and use of the software in context; 334 sets of notes from observations, researcher’ field notes, and notes from national conferences; 809 NHS documents; and 58 regional and national documents. Results: Implementation has proceeded more slowly, with a narrower scope and substantially less clinical functionality than was originally planned. The national strategy had considerable local consequences (summarised under five key themes), and wider national developments impacted heavily on implementation and adoption. More specifically, delays related to unrealistic expectations about the capabilities of systems; the time needed to build, configure, and customise the software; the work needed to ensure that systems were supporting provision of care; and the needs of end users for training and support. Other factors hampering progress included the changing milieu of NHS policy and priorities; repeatedly renegotiated national contracts; different stages of development of diverse NHS care records service systems; and a complex communication process between different stakeholders, along with contractual arrangements that largely excluded NHS providers. There was early evidence that deploying systems resulted in important learning within and between organisations and the development of relevant competencies within NHS hospitals. Conclusions: Implementation of the NHS Care Records Service in “early adopter” sites proved time consuming and challenging, with as yet limited discernible benefits for clinicians and no clear advantages for patients. Although our results might not be directly transferable to later adopting sites because the functionalities we evaluated were new and untried in the English context, they shed light on the processes involved in implementing major new systems. The move to increased local decision making that we advocated based on our interim analysis has been pursued and welcomed by the NHS, but it is important that policymakers do not lose sight of the overall goal of an integrated interoperable solution