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Aims: To develop a model to evaluate the cost-effectiveness of 4 mg dibotermin alfa/absorbable collagen sponge (ACS) versus iliac crest bone graft (ICBG) in patients with lumbar degenerative disc disease in the United Kingdom. Materials & methods: A Markov decision-analytic model was constructed to calculate costs and quality-adjusted life-years over a 4-year time horizon in each treatment group, from a United Kingdom National Health Service perspective. An individual patient data meta-analysis was undertaken to synthesize data from four randomized controlled trials and two single-arm studies concerning health-related quality of life and procedural resource use. Current cost data from the United Kingdom were then applied to determine the overall mean cost per patient in each group. One-way and probabilistic sensitivity analyses were undertaken to explore the impact of parameter uncertainty. Results: The model predicted 4-year discounted cost savings of £192 per patient treated with dibotermin alfa/ACS, compared with ICBG, and a gain of 0.0114 QALYs per patient over the same time period. Sensitivity analyses indicated that the results were most sensitive to variability in the differences in health-related quality of life and secondary surgery rate, with dibotermin alfa/ACS having a 60% probability of being cost-effective at a willingness-to-pay threshold of £20,000 per QALY gained. Limitations: There is uncertainty in the difference in cost and QALYs between the two groups. However, comprehensive sensitivity analyses were undertaken to explore this and present the results in a transparent manner. Conclusions: Our results provide an economic case for the use of 4 mg dibotermin alfa/ACS versus iliac crest bone graft, with additional health benefits predicted at reduced overall cost.

Haemophilia is predominantly an inherited disorder that impairs the body’s ability to make blood clots, a process needed to stop bleeding. The condition of this disease is complex to manage, but many patients do so through home therapy and often only see their core multidisciplinary healthcare team annually. There is an increasing need for patients to be able to monitor their condition efficiently at home while staying connected with their healthcare team. As a consequence, a low-cost handheld self-monitoring solution for clotting factor is required. Here we have demonstrated a suitable one-step Factor VIII companion diagnostic sensing approach based on a chromogenic assay for haemophilia A. The results show comparable performance to the gold standard method. Our approach is able to deliver accurate cost-effective results in under 5 min from undiluted human plasma. It has the potential to be able to reduce the human and monetary costs of over- or under-medication for haemophiliacs.

The polarization state of light is a key parameter in many imaging systems. For example, it can image mechanical stress and other physical properties that are not seen with conventional imaging, and can also play a central role in quantum sensing. However, polarization is more difficult to image and polarimetry typically involves several independent measurements with moving parts in the measurement device. Metasurfaces with interleaved designs have demonstrated sensitivity to either linear or circular/elliptical polarization states. Here we present an all-dielectric meta-polarimeter for direct measurement of any arbitrary polarization states from a single unit-cell design. By engineering a completely asymmetric design, we obtained a metasurface that can excite eigenmodes of the nanoresonators, thus displaying a unique diffraction pattern for not only any linear polarization state but all elliptical polarization states (and handedness) as well. The unique diffraction patterns are quantified into Stokes parameters with a resolution of 5$^{\circ}$ and with a polarization state fidelity of up to $99\pm1$%. This holds promise for applications in polarization imaging and quantum state tomography.

The state of polarization (SoP) is a fundamental property of electromagnetic radiation that can carry a rich set of important information in light transmitted through a test sample. Despite a wide range of applications in material identification, (thin-film) characterization, and defect analysis, the SoP remains difficult to exploit—especially at terahertz frequencies since its measurement requires complex apparatuses with multiple moving parts. We have addressed these challenges by designing a metasurface polarimeter (MSP) that incorporates the entire functionality of a division of aperture polarimeter (DoAP) with high efficiency into a single silicon layer without the need for moving parts. Collective simulations are in perfect agreement with experimental data, both confirming the intended operation. Furthermore, we present an automated analysis algorithm that allows for the complete determination of the SoP from a single image with an experimental accuracy of 92.1% ± 4.2%, following an initial calibration. We anticipate that the presented MSP will find applications in polarimetric sensing and imaging for non-destructive evaluation at terahertz frequencies.

Aims: \ud To develop a model to evaluate the cost-effectiveness of 4 mg dibotermin alfa/absorbable collagen sponge (ACS) versus iliac crest bone graft (ICBG) in patients with lumbar degenerative disc disease in the United Kingdom.\ud \ud Materials & Methods: \ud A Markov decision-analytic model was constructed to calculate costs and quality-adjusted life-years over a 4-year time horizon in each treatment group, from a United Kingdom National Health Service perspective. An individual patient data meta-analysis was undertaken to synthesize data from four randomized controlled trials and two single-arm studies concerning health-related quality of life and procedural resource use. Current cost data from the United Kingdom were then applied to determine the overall mean cost per patient in each group. One-way and probabilistic sensitivity analyses were undertaken to explore the impact of parameter uncertainty.\ud \ud Results: \ud The model predicted 4-year discounted cost savings of £192 per patient treated with dibotermin alfa/ACS, compared with ICBG, and a gain of 0.0114 QALYs per patient over the same time period. Sensitivity analyses indicated that the results were most sensitive to variability in the differences in health-related quality of life and secondary surgery rate, with dibotermin alfa/ACS having a 60% probability of being cost-effective at a willingness-to-pay threshold of £20,000 per QALY gained.\ud \ud Limitations: \ud There is uncertainty in the difference in cost and QALYs between the two groups. However, comprehensive sensitivity analyses were undertaken to explore this and present the results in a transparent manner.\ud \ud Conclusions: \ud Our results provide an economic case for the use of 4 mg dibotermin alfa/ACS versus iliac crest bone graft, with additional health benefits predicted at reduced overall cost.

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We experimentally demonstrate a CMOS compatible medium wave infrared metal-insulator-metal (MIM) metamaterial absorber structure where for a single dielectric spacer thickness at least 93% absorption is attained for 10 separate bands centred at 3.08, 3.30, 3.53, 3.78, 4.14, 4.40, 4.72, 4.94, 5.33, 5.60 μm. Previous hyperspectral MIM metamaterial absorber designs required that the thickness of the dielectric spacer layer be adjusted in order to attain selective unity absorption across the band of interest thereby increasing complexity and cost. We show that the absorption characteristics of the hyperspectral metamaterial structures are polarization insensitive and invariant for oblique incident angles up to 25° making them suitable for practical implementation in an imaging system. Finally, we also reveal that under TM illumination and at certain oblique incident angles there is an extremely narrowband Fano resonance (Q < 50) between the MIM absorber mode and the surface plasmon polariton mode that could have applications in hazardous/toxic gas identification and biosensing.

Supplementary material for the manuscript

Supplementary material for the manuscript

Stern flaps are appendages attached to the transom of a vessel which can decrease resistance at some speeds. This can translate to significant fuel savings when applied to a fleet of similar ships. A recent study investigating a stern flap design for the Canadian Navy's HALIFAX Class frigates showed a significant sensitivity to trim angle at high speeds. Further exploration on the role of trim angle was conducted using CFD simulations for three naval combatants: the Canadian HALIFAX Class, the U.S. CG-47/DD-963, and the U.S. DDG-51. The CFD simulations were validated against model test data for each hull type, and then used to determine the role of trim angle in resistance reduction from stern flaps., 27th Symposium on Naval Hydrodynamics, 5-10 October 2008, Seoul, Korea

This paper describes the results of a series of experiments on a simplified model of a 160m RO-RO ferry, after SOLAS damage. The model was a prismatic shape, primarily to allow for a direct comparison with numerical simulations. The model was tested for a range of residual freeboards from 0.5 to 1.5 metres, and a vertical centre of gravity range to cover values expected from typical existing ships and ships designed to meet SOLAS 90 regulations. The model was tested with and without a centreline casing and for a wide range of freeing port areas. Some tests were carried out with flapped covers on the freeing ports, to prevent water flowing onto the deck through the freeing ports, and some tests were carried out with permanently open freeing ports. For each condition, the highest waveheight that the model could survive and lowest waveheight that caused a capsize were determined., 4th Canadian Marine Hydromechanics and Structures Conference, June 25-27, 1997, Ottawa, Ontario

This paper describes the results of a study to investigate the effect of including a centerline fin, in combination with a steerable ducted propeller, on the manoeuvrability of a Great Lakes Bulk Carrier. The study consisted of interpreting the data obtained from manoeuvring experiments on a scale model carried out at IMD as well as similar full scale trials carried out by CSE Marine Services Inc. of St. Catherines, Ontario, on two sister ships of the same design as the model., 46th Canadian Maritime Industries Association Technical Conference, 1994, Ottawa, ON