Ethnic groups had significantly different risk of lower limb amputation, even after adjusting for demographic and some major clinical risk factors. Barriers to care should be addressed and intensive prevention strategies known to reduce the incidence of lower limb amputations could be prioritized to those at greatest risk.

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Various injectable biomaterials are developed for the minimally invasive delivery of therapeutics. Typically, a mechanical tester is used to ascertain the force required to inject these biomaterials through a given syringe‐needle system. However, currently there is no method to correlate the force measured in the laboratory to the perceived effort required to perform that injection by the end user. In this article, the injection force (F) for a variety of biomaterials, displaying a range of rheological properties, is compared with the effort scores from a 50 person panel study. The maximum injection force measured at crosshead speed 1 mm s−1 is a good proxy for injection effort, with an R2 of 0.89. This correlation leads to the following conclusions: participants can easily inject 5 mL of substance for F < 12 N; considerable effort is required to inject 5 mL for 12 N < F < 38 N; great effort is required and <5 mL can be injected for 38 N < F < 64 N; and materials are entirely non‐injectable for F > 64 N. These values may be used by developers of injectable biomaterials to make decisions about formulations and needle sizes early in the translational process.

Carbon dioxide capture and storage (CCS) is one of the technologies that have been proposed to reduce emissions of carbon dioxide (CO2) to the atmosphere. CCS will require the transportation of the CO2 from the “capture” locations to the “storage” locations via large-scale pipeline projects. One of the key requirements for the design and operation of pipelines in all jurisdictions is fracture control. Supercritical CO2 is a particularly challenging fluid from this point of view, because its thermodynamic characteristics are such that a very high driving force for fracture can be sustained for a long time. Even though CO2 is not flammable, it is an asphyxiating gas that is denser than air, and can collect in low-lying areas. Additionally, it is well known that any pipeline rupture, regardless of the nature of the fluid it is transporting, has a damaging reputational, commercial, logistic, and end user impact. Therefore, it is as important to control fracture in a CO2 pipeline as in one transporting a flammable fluid. With materials specified appropriately for the prevention of brittle failure, the key element is the control of propagating ductile (or tearing) fracture. The determination of the required toughness for the arrest of ductile fracture requires knowledge of the decompression behavior of the contained fluid, which in turn requires accurate knowledge of its thermodynamic characteristics along the decompression isentrope. While thermodynamic models based on appropriate EOS (equations of state) are available that will, in principle, allow determination of the decompression wave speed, they, in general, have not been fully validated for very rapid transients following a rupture. This paper presents experimental results of the decompression wave speed obtained from shock tube tests conducted on pure CO2 from different initial conditions, and comparison with predictions by models based on GERG-2008, Peng-Robinson, and BWRS equations of state (EOS). These tests were conducted as a baseline before introducing various impurities.

The current treatments for the management of corneal and scleral perforations include sutures and adhesives. While sutures are invasive, induce astigmatism and carry a risk of infection, cyanoacrylate glues are toxic, proinflammatory and form an opaque and rough surface that precludes vision. Consequently, the clinical need for a fast curing and strong tissue adhesive with minimised cytotoxicity and host inflammation remains unmet. In this paper, we engineer a gelatine methacryloyl (GelMA) adhesive that can be crosslinked in situ within 2 min using UV or visible light and a riboflavin (RF)/sodium persulfate (SPS) system. Optical coherence tomography (OCT) images demonstrated that the flowable GelMA adhesive could completely fill corneal wounds and restore the ocular curvature by forming a smooth contour on the ocular surface. Further, ex vivo studies in porcine eyes showed that GelMA bioadhesives exhibited burst pressures that were comparable to cyanoacrylates (49 ± 9 kPa), with the hydrogels exhibiting a transmittance (90%), water content (85%) and storage modulus (5 kPa) similar to the human cornea. Finally, using human dermal fibroblasts, we showed that our GelMA adhesive was non-toxic and could effectively support cell adhesion and proliferation. Taken together, the adhesive’s performance, injectability and ease of administration, together with gelatin’s availability and cost-effectiveness, make it a potential stromal filler or sealant for corneal and conjunctival applications.

Transition interventions aim to improve care and reduce hospital readmissions but evaluations of these interventions have reported inconsistent results. We report on the evaluation of an intervention implemented in Auckland, New Zealand. Participants were people over the age of 65 who had an acute medical admission and were at high risk of readmission. The intervention included an improved discharge process and nurse telephone follow-up soon after discharge. Outcomes were 28 day readmission rates and emergency attendances. The study is observational, using both interrupted times series and regression discontinuity designs. 5239 patients were treated over a one year period. There was no change in readmission rates or ED attendances or secondary outcomes. Not all patients received all components of the intervention. This transition intervention was not successful. Possible reasons for this and implications are discussed. Although non-experimental methods were used, we believe the results are robust.

Extracellular Vesicles (EVs) are considered promising nanoscale therapeutics for bone regeneration. To date, EVs are typically procured from cells on 2D tissue culture plastic, an artificial environment that limits cell growth and does not replicate in situ biochemical or biophysical conditions. This study investigated the potential of 3D printed titanium scaffolds coated with hydroxyapatite to promote the therapeutic efficacy of osteoblast-derived EVs. Ti6Al4V titanium scaffolds with different pore sizes (500 and 1000 µm) and shapes (square and triangle) were fabricated by selective laser melting. A bone-mimetic nano-needle hydroxyapatite (nnHA) coating was then applied. EVs were procured from scaffold-cultured osteoblasts over 2 weeks and vesicle concentration was determined using the CD63 ELISA. Osteogenic differentiation of human bone marrow stromal cells (hBMSCs) following treatment with primed EVs was evaluated by assessing alkaline phosphatase activity, collagen production and calcium deposition. Triangle pore scaffolds significantly increased osteoblast mineralisation (1.5-fold) when compared to square architectures (P ≤ 0.001). Interestingly, EV yield was also significantly enhanced on these higher permeability structures (P ≤ 0.001), in particular (2.2-fold) for the larger pore structures (1000 µm). Furthermore osteoblast-derived EVs isolated from triangular pore scaffolds significantly increased hBMSCs mineralisation when compared to EVs acquired from square pore scaffolds (1.7-fold) and 2D culture (2.2-fold) (P ≤ 0.001). Coating with nnHA significantly improved osteoblast mineralisation (&gt;2.6-fold) and EV production (4.5-fold) when compared to uncoated scaffolds (P ≤ 0.001). Together, these findings demonstrate the potential of harnessing bone-mimetic culture platforms to enhance the production of pro-regenerative EVs as an acellular tool for bone repair.