Acid erosion due to food and drink intake in particular and tooth surface loss due to general wear of the dentition is a global problem. Continual erosion and loss of the surface enamel of the tooth leads to hypersensitivity. This oral condition is acute in both children and the ageing population of society and can have a significant impact on the quality of life. The 2011 census points out that 16.3% of the population of England and N Ireland is above 65 years old (Daily Telegraph 17 July 2012), which suggests that the number of people suffering from acid erosion may continue to rise in years to come. This means that there is an even more urgent need to provide a robust solution for restoring lost enamel, a problem that remains intractable for clinical dentistry. To address this problem, we propose research into an engineering methodology to spray the tooth with a thin mineral layer that is then densified and bonded to the underlying tooth using an ultrafast laser irradiation pulse. The cross-disciplinary LUMIN project will develop and exploit the technology of micro-nozzle bio-mineral delivery in Task (a) and its subsequent sintering using femto-second pulsed (fsp) lasers for the restoration of acid-eroded enamel. The operating wavelength of the proposed fsp lasers will be in the eye-safe regions of the near-IR (1500-2100 nm) and will offer flexibility in terms of energy/power delivery by engineering the laser cavity, which is the main goal of Task (b). An additional goal of Task (b), as stated in the objective section above, is to integrate the micro-nozzle bio-mineral delivery system from Task (a) with lasers on a single platform for achieving rapid sintering in the deposited bio-mineral layers on to the acid-eroded enamel surface. During this research, novel acid-resistant enamel mineral substitutes, in crystalline and gel forms, will be engineered and optimized for the micro-nozzle delivery in Task (a). The integration of the materials delivery system with the fsp-laser will then yield simultaneous sintering.. The engineering approaches herein will therefore yield 3 different platform technologies for future exploitation, which will be achieved with the support from the Integrated Knowledge Centre on Tissue Engineering and Medical Technologies at Leeds. We will investigate whether the use of a micro-nozzle for gel and suspension materials with an fsp-laser poses a risk of toxicity due to generation and release of nano-scale particulates (some may argue these might be photosensitized by the intense beam of the fsp-laser). In Task (c) we will therefore assess any nano-particle and photo-induced toxicity and perform a risk analysis. This will conform to standard clinical procedures with an aim to thus identify and minimise any imminent risk. Following Task (c), our goal in Task (d) is to implement the engineering approaches, developed in Tasks (a) and (b) together with the risk mitigation strategy in Task (c) for testing fsp-laser sintered enamel minerals in the oral environment using in-situ mouth appliance trials, a technique pioneered at the Leeds Dental Institute to minimising the risks in extensive in-vivo trials. In Task (d) the sintered materials will be characterised for acid erosion, durability, hardness, toughness, and flexural bend with using the assembled academic expertise in materials science and engineering and clinical dentistry. The IKC team will provide support, via Dr. Graeme Howling's expertise, to develop technology exploitation through the project partners, M-Squared Lasers, British Glass, and Giltec in the first instance. The project also aims to establish academic links with overseas academic institutions e.g. the IMI at Lehigh and Penn State in Materials Science, and with Stanford and Caltec in the US via the SUPA led EPSRC funded collaboration. The industry-academia link with the Photonics KTN in the UK is also expected to develop during the course of project.

ENCASE will leverage the latest advances in usable security and privacy to design and implement a browser-based architecture for the protection of minors from malicious actors in online social networks. The ENCASE user-centric architecture will consist of three distinct services, which can be combined to form an effective protective net against cyberbullying and sexually abusive acts: a) a browser add-on with its corresponding scalable back-end software stack that collects the users’ online actions to unveil incidents of aggressive or distressed behavior; b) a browser add-on with its associated scalable software stack that analyses social web data to detect fraudulent and fake activity and alert the user; and c) a browser add-on that detects when a user is about to share sensitive content (e.g., photos or address information) with an inappropriate audience and warns the user or his parents of the imminent privacy threat. The third add-on has usable controls that enable users to protect their content by suggesting suitable access lists, by watermarking, and by securing the content via cryptography or steganography. The three browser add-ons and the back-end social web data analytics software stack will be assessed with user studies and piloting activities and will be released to the public. The foundation of the research and innovation activities will be a diligently planned inter-sectorial and interdisciplinary secondment program for Experienced and Early Stage Researchers that fosters knowledge exchange. The academic partners will contribute know-how on user experience assessment, large scale data processing, machine learning and data-mining algorithm design, and content confidentiality techniques. The industrial partners will primarily offer expertise in production-grade software development, access to real-world online social network data, and access to numerous end-users through widely deployed products.

Deaths and injuries from the effects of land-mines are common results of both active war-zones and post-conflict legacies. Aside from the regular headline-making news when UK armed forces are attacked by IEDs, it has been calculated that some 110 million land-mines are left in post-conflict zones, leading to the death of around 800 people per month and the maiming of many others. Development of protective clothing and footwear, vehicle design and retrofitting systems and efficient mine clearance systems for both active defence and civilian mine-clearance operatives, depends on the accurate assessment of the blast loading produced by the detonation of a shallow-buried explosive. This is a highly complex detonation event, involving the interaction of extremely high-energy shock waves with multiple materials in different phases (soil, air and water). This project aims to develop a deep understanding of how the soil surrounding buried explosives affects the resulting detonation and to develop advanced soil models which describe this behaviour. With a newly applied methodology this project aims to test clays with a high degree of accuracy to develop a dataset that will complement an existing equivalent data for sands and gravels. This will allow a direct comparison between the two soil types to assess the main contributing factors to the blast created during the tests. It has been postulated by other researchers that the resulting impulse given out by a shallow buried explosive is inversely proportional to the shear strength of the soil in which the explosive is buried. This hypothesis is to be tested by developing a new high pressure, high strain rate testing apparatus to shear soils in similar conditions to those experienced in explosive events. This novel apparatus will for the first time be able to investigate the fundamental shear properties of compressible materials. The understanding gained from this project will provide a revolutionary dataset for the modelling of soil-explosive interaction events and lead to developments in protective solutions for both civilian and defence applications.

Optical imaging is perhaps the single most important sensor modality in use today. Its use is widespread in consumer, medical, commercial and defence technologies. The most striking development of the last 20 years has been the emergence of digital imaging using complementary metal oxide semiconductor (CMOS) technology. Because CMOS is scalable, camera technology has benefited from Moore's law reduction in transistor size so that it is now possible to buy cameras with more than 10 MegaPixels for £50. The same benefits are beginning to emerge in other imaging markets - most notably in infrared imaging where 64x64 pixel thermal cameras can be bought for under £1000. Far infrared (FIR), or terahertz, imaging is now emerging as a vital modality with application to biomedical and security imaging, but early imaging arrays are still only few pixel research ideas and prototypes that we are currently investigating. There has been no attempt to integrate the three different wavelength sensors coaxially on to the same chip. Sensor fusion is already widespread whereby image data from traditional visible and mid infrared (MIR) sensors is overlaid to provide a more revealing and data rich visualisation. Image fusion permits discrepancies to be identified and comparative processing to be performed. Our aim is to create a "superspectral" imaging chip. By superspectral we mean detection in widely different bands, as opposed to the discrimination of many wavelengths inside a band - e.g. red, green and blue in the visible band. We will use "More than Moore" microelectronic technology as a platform. By doing so, we will leverage widely available low-cost CMOS to build new and economically significant technologies that can be developed and exploited in the UK. There are considerable challenges to be overcome to make such technology possible. We will hybridise two semiconductor systems to integrate efficient photodiode sensors for visible and MIR detection. We will integrate bolometric sensing for FIR imaging. We will use design and packaging technologies for thermal isolation and to optimise the performance of each sensor type. We will use hybridised metamaterial and surface plasmon resonance technologies to optimise wavelength discrimination allowing vertical stacking of physically large (i.e. FIR) sensors with visible and MIR sensors. We ultimate want to demonstrate the world's first ever super-spectral camera.

Global demand for high power microwave electronic devices that can deliver power densities well exceeding current technology is increasing. In particular Gallium Nitride (GaN) based high electron mobility transistors (HEMTs) are a key enabling technology for high-efficiency military and civilian microwave systems, and increasingly for power conditioning applications in the low carbon economy. This material and device system well exceeds the performance permitted by the existing Si LDMOS, GaAs PHEMT or HBT technologies. GaN-based HEMTs have reached RF power levels up to 40 W/mm, and at frequencies exceeding 300 GHz, i.e., a spectacular performance enabling disruptive changes for many system applications. However, transistor reliability is driven by electric field and channel temperature, so self-heating means in practice that reliable devices can only be operated up to RF power densities of 10 W/mm in contrast to the 40 W/mm hero data published in the literature. Considerable concern also exists in the UK and across Europe that access to state-of-the-art GaN microwave technology is limited by US ITAR (International Traffic in Arms Regulation) restrictions. The most advanced capabilities for all elements of GaN HEMT technology, using traditional SiC substrates, epitaxy and device processing currently reside in the US, with restricted access by UK industry. The vision of Integrated GaN-Diamond Microwave Electronics: From Materials, Transistors to MMICs (GaN-DaME) is to develop transformative GaN-on-Diamond HEMTs and MMICs, the technology step beyond GaN-on-SiC, which will revolutionize the thermal management which presently limits GaN electronics. Challenges occur in terms of how to integrate such dissimilar materials into a reliable device technology. The outcome will be devices with a >5x increase in RF power compared to GaN-on-SiC, or alternatively and equally valuably, a dramatic 'step-change' shrinkage in MMIC or PA size, and hence an increase in efficiency through the removal of lossy combining networks as well as a reduction in power amplifier (PA) cost. This represents a disruptive change in capability that will allow the realisation of new system architectures e.g. for RF seekers and medical applications, and enable the bandwidths needed to deliver 5G and beyond. Reduced requirements for cooling / increased reliability will result in major cost savings at the system level. To enable our vision to become reality, we will develop new diamond growth approaches that maximize diamond thermal conductivity close to the active GaN device area. In present GaN-on-Diamond devices a thin dielectric layer is required on the GaN surface to enable seeding and successful deposition of diamond onto the GaN. Unfortunately, most of the thermal barrier in these devices then exists at this GaN-dielectric-diamond interface, which has much poorer thermal conductivity than desired. Any reduction in this thermal resistance, either by removing the need for a dielectric seeding layer for diamond growth, or by optimizing the grain structure of the diamond near the seeding, would be of huge benefit. Novel diamond growth will be combined with innovative micro-fluidics using phase-change materials, a dramatically more powerful approach than conventional micro-fluidics, to further aid heat extraction. An undiscussed consequence of using diamond, its low dielectric constant, which poses challenges and opportunities for microwave design will be exploited. At the most basic level, the reliability of this technology is not known. For instance, at the materials level the diamond and GaN have very different coefficients of thermal expansion (CTE). Mechanically rigid interfaces will need to be developed including interdigitated GaN-diamond interfaces.