Design of slurries for 3D printing of sodium-ion battery electrodes

Additive manufacturing of battery electrodes, using syringe deposition 3D printing or direct ink writing methods, enables intricate microstructural design. This process differs from traditional blade or slot-die coating methods, necessitating tailored physical properties of composite slurries to ensure successful deposition. Inadequately optimised slurries result in non-uniform extrusion, and challenges such as nozzle swelling or slumping, result in compromised structural integrity of the print, limiting the resolution. This study focuses on developing slurry design principles by thoroughly characterising the rheology of several water-based hard carbon anode slurry, both in shear and extension. Hard carbon is chosen as a material of significant importance for future sodium-ion batteries, and an example for this optimisation. The slurry composition is tailored to introduce yield stress by incorporating network-forming binder (carrageenan) and additive (carbon nanotubes), effectively reducing spreading, and preserving the printed coating's structure. Validation is performed through printing a large width line and evaluating spread. The same slurry is deposited on a smaller 150 μm nozzle, which introduces die swell and spreading effects. This offers insights for further optimization strategies. The strategies developed in this research for characterizing and optimizing the rheology through formulation lay the groundwork for the advancement of detailed 3D printed electrodes, contributing to the progress of additive manufacturing technologies in the field of battery manufacturing.</p

Structural basis for the photoconversion of a phytochrome to the activated far-red light-absorbing form

Phytochromes are a collection of bilin-containing photoreceptors that regulate numerous photoresponses in plants and microorganisms through their ability to photointerconvert between a red light-absorbing, ground state Pr and a far-red light-absorbing, photoactivated state Pfr1,2. While the structures of several phytochromes as Pr have been determined3-7, little is known about the structure of Pfr and how it initiates signaling. Here, we describe the three-dimensional solution structure of the bilin-binding domain as Pfr using the cyanobacterial phytochrome from Synechococcus OSB’. Contrary to predictions, light-induced rotation of the A but not the D pyrrole ring is the primary motion of the chromophore during photoconversion. Subsequent rearrangements within the protein then affect intra- and interdomain contact sites within the phytochrome dimer. From our models, we propose that phytochromes act by propagating reversible light-driven conformational changes in the bilin to altered contacts between the adjacent output domains, which in most phytochromes direct differential phosphotransfer

Mobilise-D insights to estimate real-world walking speed in multiple conditions with a wearable device

This study aimed to validate a wearable device’s walking speed estimation pipeline, considering complexity, speed, and walking bout duration. The goal was to provide recommendations on the use of wearable devices for real-world mobility analysis. Participants with Parkinson’s Disease, Multiple Sclerosis, Proximal Femoral Fracture, Chronic Obstructive Pulmonary Disease, Congestive Heart Failure, and healthy older adults (n = 97) were monitored in the laboratory and the real-world (2.5 h), using a lower back wearable device. Two walking speed estimation pipelines were validated across 4408/1298 (2.5 h/laboratory) detected walking bouts, compared to 4620/1365 bouts detected by a multi-sensor reference system. In the laboratory, the mean absolute error (MAE) and mean relative error (MRE) for walking speed estimation ranged from 0.06 to 0.12 m/s and − 2.1 to 14.4%, with ICCs (Intraclass correlation coefficients) between good (0.79) and excellent (0.91). Real-world MAE ranged from 0.09 to 0.13, MARE from 1.3 to 22.7%, with ICCs indicating moderate (0.57) to good (0.88) agreement. Lower errors were observed for cohorts without major gait impairments, less complex tasks, and longer walking bouts. The analytical pipelines demonstrated moderate to good accuracy in estimating walking speed. Accuracy depended on confounding factors, emphasizing the need for robust technical validation before clinical application. Trial registration: ISRCTN – 12246987

Crystal Structure of Deinococcus Phytochrome in the Photoactivated State Reveals a Cascade of Structural Rearrangements during Photoconversion

Phytochromes are photochromic photoreceptors responsible for a myriad of red/far-red light-dependent processes in plants and microorganisms. Interconversion is initially driven by photoreversible isomerization of bilin, but how this alteration directs the photostate-dependent changes within the protein to actuate signaling is poorly understood. Here, we describe the structure of the Deinococcus phytochrome photosensory module in its near complete far-red light-absorbing Pfr state. In addition to confirming the 180° rotation of the D-pyrrole ring, the dimeric structure clearly identifies downstream rearrangements that trigger large-scale conformational differences between the dark-adapted and photoactivated states. Mutational analyses verified the importance of residues surrounding the bilin in Pfr stabilization, and protease sensitivity assays corroborated photostate alterations that propagate along the dimeric interface. Collectively, these data support a cooperative toggle model for phytochrome photoconversion and advance our understanding of the allosteric connection between the photosensory and output modules

Single-Lap Shear Tests Database on EB-FRP <i>(</i><i>Appendix for FRPRCS & ACI Special Publications)</i>

This meticulously curated dataset encompasses 1,627 single lap shear tests performed on externally reinforced concrete members using FRP strips or ties, spanning studies from 1994 to 2022. These studies have been diligently sourced from the Scopus and Web of Science databases to provide a cohesive and extensive overview of the developments in the field of concrete reinforcement.While material testing insights are included, they predominantly pertain to the more recent large-scale tests executed by Simpson Strong-Tie Inc. These inclusions, albeit not the central focus, do add nuanced layers to the comprehensive academic research presented.Additionally, the dataset features Paper No. 418 in FRPRCS (Fiber-Reinforced Polymer Reinforcement for Concrete Structures) and the accepted full paper is published in an ACI SP (American Concrete Institute Special Publication), supplementing the overall compilation with enriched academic viewpoints and findings.The objective of this assembled dataset is to serve as a substantial, integrated resource for academics, researchers, and industry professionals. It provides a balanced, encompassing view of the theoretical foundations and practical applications of FRP reinforcements in concrete members, enabling users to explore and understand the progressive methodologies and varied applications in the domain over the designated period.</p

Identifying neural signatures mediating behavioral symptoms and psychosis onset: High-dimensional whole brain functional mediation analysis.

Along the pathway from behavioral symptoms to the development of psychotic disorders sits the multivariate mediating brain. The functional organization and structural topography of large-scale multivariate neural mediators among patients with brain disorders, however, are not well understood. Here, we design a high-dimensional brain-wide functional mediation framework to investigate brain regions that intermediate between baseline behavioral symptoms and future conversion to full psychosis among individuals at clinical high risk (CHR). Using resting-state functional magnetic resonance imaging (fMRI) data from 263 CHR subjects, we extract an α brain atlas and a β brain atlas: the former underlines brain areas associated with prodromal symptoms and the latter highlights brain areas associated with disease onset. In parallel, we identify and separate mediators that potentially positively and negatively mediate symptoms and psychosis, respectively, and quantify the effect of each neural mediator on disease development. Taken together, these results paint a brain-wide picture of neural markers that are potentially mediating behavioral symptoms and the development of psychotic disorders; additionally, they underscore a statistical framework that is useful to uncover large-scale intermediating variables in a regulatory biological system