3D Printing of Ridged FeS2 Cathodes for Improved Rate Capability and Custom-Form Lithium Batteries.

Additive manufacturing can enable the fabrication of batteries in nonconventional form factors, enabling higher practical energy density due to improved material packing efficiency of power sources in devices. Furthermore, energy density can be improved by transitioning from conventional Li-ion battery materials to lithium metal anodes and conversion cathodes. Iron disulfide (FeS2) is a prominent conversion cathode of commercial interest; however, the direct-ink-write (DIW) printing of FeS2 inks for custom-form battery applications has yet to be demonstrated or optimized. In this work, DIW printing of FeS2 inks is used to systematically investigate the impact of ink solid concentration on rheology, film shape retention on arbitrary surfaces, cathode morphology, and electrochemical cell performance. We find that cathodes with a ridged interface, produced from the filamentary extrusion of highly concentrated FeS2 inks (60-70% solids w/w%), exhibit optimal power, uniformity, and stability when cycled at higher rates (in excess of C/10). Meanwhile, cells with custom-form, wave-shaped electrodes (printed FeS2 cathodes and pressed lithium anodes) are demonstrated and shown to exhibit similar performance to comparable cells in planar configurations, demonstrating the feasibility of printing onto complex geometries. Overall, the DIW printing of FeS2 inks is shown to be a viable path toward the making of custom-form conversion lithium batteries. More broadly, ridging is found to optimize rate capability, a finding that may have a broad impact beyond FeS2 and syringe extrusion.

Equality and diversity in health governance systems: are we getting it right and are there lessons from COVID-19?

The COVID-19 pandemic highlighted major challenges in governance and inequalities particularly among those from Black, Asian and minority ethnic (BAME) groups. This paper focuses on the BAME community and explores this through a governance lens, with particular reference to the representation and functioning of boards involved in healthcare and building a transparent culture. To illustrate this, the paper utilises a series of structured reflective questions with model answers termed Right Question, Right Answer and links to the Centre for Quality in Governance (CQG) Maturity Matrix. This article highlights the need to improve diversity and accountability of health and care organisations to their staff and local population. For governance to be effective, it must be aligned and comply with healthcare system regulations to ensure improvement of legislative acts and standards. The paper aims to inform government policy by moving from rhetoric, or merely describing challenges, to action and change by increasing accountability.

Materials characterization of Feraheme/ferumoxytol and preliminary evaluation of its potential for magnetic fluid hyperthermia.

Feraheme, is a recently FDA-cleared superparamagnetic iron oxide nanoparticle (SPION)-based MRI contrast agent that is also employed in the treatment of iron deficiency anemia. Feraheme nanoparticles have a hydrodynamic diameter of 30 nm and consist of iron oxide crystallites complexed with a low molecular weight, semi-synthetic carbohydrate. These features are attractive for other potential biomedical applications such as magnetic fluid hyperthermia (MFH), since the carboxylated polymer coating affords functionalization of the particle surface and the size allows for accumulation in highly vascularized tumors via the enhanced permeability and retention effect. This work presents morphological and magnetic characterization of Feraheme by transmission electron microscopy (TEM), Energy dispersive X-ray spectroscopy (EDX), and superconducting quantum interference device (SQUID) magnetometry. Additionally, the results of an initial evaluation of the suitability of Feraheme for MFH applications are described, and the data indicate the particles possess promising properties for this application.

High field magnetic resonance microscopy of the human hippocampus in Alzheimer's disease: quantitative imaging and correlation with iron.

We report R(2) and R(2) in human hippocampus from five unfixed post-mortem Alzheimer's disease (AD) and three age-matched control cases. Formalin-fixed tissues from opposing hemispheres in a matched AD and control were included for comparison. Imaging was performed in a 600MHz (14T) vertical bore magnet at MR microscopy resolution to obtain R(2) and R(2) (62 µm×62 µm in-plane, 80 µm slice thickness), and R(1) at 250 µm isotropic resolution. R(1), R(2) and R(2) maps were computed for individual slices in each case, and used to compare subfields between AD and controls. The magnitudes of R(2) and R(2) changed very little between AD and control, but their variances in the Cornu Ammonis and dentate gyrus were significantly higher in AD compared for controls (p<0.001). To investigate the relationship between tissue iron and MRI parameters, each tissue block was cryosectioned at 30 µm in the imaging plane, and iron distribution was mapped using synchrotron microfocus X-ray fluorescence spectroscopy. A positive correlation of R(2) and R(2)* with iron was demonstrated. While studies with fixed tissues are more straightforward to conduct, fixation can alter iron status in tissues, making measurement of unfixed tissue relevant. To our knowledge, these data represent an advance in quantitative imaging of hippocampal subfields in unfixed tissue, and the methods facilitate direct analysis of the relationship between MRI parameters and iron. The significantly increased variance in AD compared for controls warrants investigation at lower fields and in-vivo, to determine if this parameter is clinically relevant.

Re-energising Clinical Governance through Integrated Governance.

The purpose of this paper is to accurately identify the future governance arrangements the NHS will follow, a close examination of the roles of Directors in implementing such a policy, and the National Policy documents that are required to put this in place.