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Backgrounds: Rapid response team or medical emergency team (MET) calls are typically activated by significant alterations of vital signs in inpatients. However, the clinical significance of a specific criterion, blood pressure elevations, is uncertain. Objectives: The aim of this study was to evaluate the likelihood ratios associated with MET-activating vital signs, particularly in-patient hypertension, for predicting in-hospital mortality among general medicine inpatients who met MET criteria at any point during admission in a South Australian metropolitan teaching hospital. Results: Among the 15,734 admissions over a two-year period, 4282 (27.2%) met any MET criteria, with a positive likelihood ratio of 3.05 (95% CI 2.93 to 3.18) for in-hospital mortality. Individual MET criteria were significantly associated with in-hospital mortality, with the highest positive likelihood ratio for respiratory rate ≤ 7 breaths per minute (9.83, 95% CI 6.90 to 13.62), barring systolic pressure ≥ 200 mmHg (LR + 1.26, 95% CI 0.86 to 1.69). Conclusions: Our results show that meeting the MET criteria for hypertension, unlike other criteria, was not significant associated with in-hospital mortality. This observation warrants further research in other patient cohorts to determine whether blood pressure elevations should be routinely included in MET criteria.

Abstract To recharge lithium‐ion batteries quickly and safely while avoiding capacity loss and safety risks, a novel electrode design that minimizes cell polarization at a higher current is highly desired. This work presents a dual‐layer electrode (DLE) technology via sequential coating of two different anode materials to minimize the overall electrode resistance upon fast charging. Electrochemical impedance spectroscopy and distribution of relaxation times analysis revealed the dynamic evolution of electrode impedances in synthetic graphite (SG) upon a change in the state of charge (SOC), whereas the natural graphite (NG) maintains its original impedance regardless of SOC variation. This disparity dictates the sequence of the NG and SG coating layers within the DLE, considering the temporal SOC gradient developed upon fast charging. Simulation and experimental results suggest that DLE positioning NG and SG on the top (second‐layer) and bottom (first‐layer), respectively, can effectively reduce the overall resistance at a 4 C‐rate (15‐min charging), demonstrating two times higher capacity retention (61.0%) over 200 cycles than its counterpart with reversal sequential coating, and is higher than single‐layer electrodes using NG or NG/SG binary mixtures. Hence, this study can guide the combinatorial sequence for multi‐layer coating of various active materials for a lower‐resistivity, thick‐electrode design.

The increasing demand for batteries with high‐energy densities for applications such as electric vehicles necessitates a paradigm shift from the use of conventional graphite as anodes. Li metal is spotlighted as a replacement for graphite due to its ultrahigh theoretical capacity (3860 mAh g−1). However, Li metal foil is plagued with limited cycle life and safety concerns due to poor Coulombic efficiency and uncontrollable growth of Li dendrites. To overcome these challenges, utilizing Li metal in powder form instead of the conventional foil proves to be advantageous. The anode consisting of spherical‐shaped Li metal powders (LMPs) has a larger surface area than Li metal foil, resulting in a lower effective current density. Furthermore, using the powder‐based slurry process facilitates the fabrication of large‐area and thin‐film (≤20 μm) Li anodes. In this review, the various fabrication methods and surface stabilization techniques of LMPs are summarized with their associated patents. Also, research trends with regard to LMP‐based anodes toward high‐performance Li metal batteries (LMBs) are carefully presented. Additionally, the application of LMPs as prelithiation agents in electrode active materials for batteries and capacitors is outlined. Finally, perspectives are suggested regarding the future of LMPs to accelerate the commercialization of advanced LMBs.

Highlights Sulfonated polyvinylidene fluoride (S-PVdF) binders with improved hydrophilicity were synthesized via a simple sulfonation process of conventional hydrophobic PVdF binders. The abundant sulfonate groups of S-PVdF binders significantly improved ionic conduction in thick electrodes (~ 6 mg cm−2), enabling improved reversible capacities under various current densities. The S-PVdF binders effectively suppressed cathode dissolution, resulting in enhanced capacity retention at higher temperature operations (45 °C).

Abstract The electrode structure is a crucial factor for all‐solid‐state batteries (ASSBs) since it affects the electronic and ionic transport properties and determines the electrochemical performance. In terms of electrode structure design, a single‐ion conducting solid polymer electrolyte (SIC‐SPE) is an attractive solid electrolyte (SE) for the composite electrode among various SEs. Although the ionic conductivity of SIC‐SPE is lower than other inorganic SEs, the SIC‐SPE has a relatively lower density and can form an intimate contact between the SE and active materials (AM), resulting in an excellent electrode structure. The electrochemical performance of the cell with SIC‐SPE was comparable with the cell with Li6PS5Cl (LPSCl), which has 10 times higher intrinsic ionic conductivity than SIC‐SPE (SIC‐SPE: 0.2 × 10−3 S cm−1, LPSCl: 2.2 = 10−3 S cm−1 at 25°C). 3D digital‐twin‐driven simulation showed that the electrode with SIC‐SPE has a higher SE volume fraction, a lower tortuosity, and a larger AM/SE contact area than the LPSCl electrode. The favorable structure of the SIC‐SPE electrode leads to lower overpotential than the LPSCl electrode during operation. Our results suggest that the SIC‐SPE is a promising SE for making a good electrode structure in ASSBs.

Abstract The combination of a high‐Ni LiNixMnyCo1−x−yO2 (NMC) cathode and Li metal anode is currently considered the most promising candidate for high‐energy‐density Li‐metal batteries. However, undesired parasitic reactions in LiPF6‐based carbonate electrolytes hinder their further application. Herein, we report a new fluorinated linear carbonate additive, ethyl 2‐(2‐fluoroethoxy)ethyl carbonate) (EFEEC), to a lithium bis(trifluoromethanesulfonyl) imide–lithium bis(oxalate)borate‐based dual‐salt electrolyte system which is compatible with high‐Ni NMC and Li metal electrodes. We showed that in our electrolyte with well‐controlled lowest unoccupied molecular orbital/highest unoccupied molecular orbital levels, robust and stable solid electrolyte interphases are formed on both the cathode and anode synergistically, which enables neat and dense lithium metal deposition as well as the structural stability of NMC622 operated under a 4.5 V cut‐off voltage. The use of the dual‐salt‐based electrolyte with the EFEEC additive improved cycle performance with high‐capacity retention (76.0% at 200 cycles) even when operated under high voltage.

We developed a thermo-electrochemical model of a 50 Ah pouch-type lithium-ion cell and utilized a cell model to build an 18.5 V/50 Ah module to analyze the thermal behavior under various operating conditions and design cooling systems for optimal operating temperature ranges. Specifically, the heat generated by electrochemical reactions was simulated through an electrochemical cell model, and then the calculated heat was coupled with a heat transfer model reflecting the actual 3D structure of the cell. By fitting two temperature-dependent parameters, i.e., the chemical diffusion coefficient and exchange current density, the model accurately estimated the electrochemical and thermal properties with errors less than 3%, even under wide temperature (25°C, 35°C, and 45°C) and C-rate (0.5, 1, 2, and 5C) conditions. Based on this reliable cell model, we built an 18.5 V/50 Ah module model with five cells in series to simulate both the amount of heat generated and the required heat sink. Finally, both the cell and module models were used to predict the electrochemical and thermal behaviors under actual wireless tram operations in Turkey. The model results were compared with experimental results to confirm their reliability.

The internal short circuit caused by the Li dendrite is well known to be a major cause for fire or explosion accidents involving state-of-the-art lithium-ion batteries (LIBs). However, post-mortem analysis cannot identify the most probable cause, which is initially embedded in the cell, because the original structure of the cell totally collapses after the accident. Thus, multiphysics modeling and simulation must be an effective solution to investigate the effect of a specific cause in a variety of conditions. Herein, we reported an electrochemical-thermal model to simulate the internal short circuit depending on Li dendrite’s sizes (1, 3, 5, 7, and 9 μm), quantities (1–9), relative locations (0, 25, 50, 100, and 150 μm), and external temperature (−10, 10, 30, and 50°C). Through monitoring the temperature change affected by the joule and reaction heats for each case, we suggested critical conditions that led to unavoidable thermal runaway. Thus, this model can be a steppingstone in understanding the correlation between internal short circuits and Li dendrites.

Objective To investigate variables for assessment of stroke-related sarcopenia that are alternative options to the current assessment for sarcopenia, which focuses on age-related sarcopenia and also has limitations in addressing sarcopenia due to weakness resulting from stroke. Methods Forty patients (17 men, 23 women; mean age, 66.9±15.4 years) with first-ever stroke who can walk independently were included. Muscle mass was determined by measuring ultrasonographic muscle thickness of vastus intermedius, rectus femoris, tibialis anterior, medial gastrocnemius, and biceps brachii muscles in addition to using the skeletal muscle index (SMI) with bioelectrical impedance analysis. Muscle strength was assessed with the Medical Research Council (MRC) sum score as well as handgrip (HG) strength. Physical performance was measured by the Berg Balance Scale (BBS) along with 4-meter gait speed (4MGS). Correlations between each assessment in the three categories were analyzed and adjusted by stroke severity, comorbidity, and nutritional status. Results For muscle mass, SMI showed the highest correlation with the tibialis anterior muscle (r=0.783, p

We demonstrate that dispersion stability and excellent coating quality are achieved in polyethylene (PE) separators by premixing heterogeneous ceramics such as silica (SiO2) and alumina (Al2O3) in an aqueous solution, without the need for functional additives such as dispersing agents and surfactants. Due to the opposite polarities of the zeta potentials of SiO2 and Al2O3, SiO2 forms a sheath around the Al2O3 surface. Electrostatic repulsion occurs between the Al2O3 particles encapsulated in SiO2 to improve the dispersion stability of the slurry. The CCSs fabricated using a dual ceramic (SiO2 and Al2O3)-containing aqueous coating slurry, denoted as DC-CCSs, exhibit improved physical properties, such as a wetting property, electrolyte uptake, and ionic conductivity, compared to bare PE separators and CCSs coated with a single ceramic of Al2O3 (SC-CCSs). Consequently, DC-CCSs exhibit an improved electrochemical performance, in terms of rate capability and cycle performance. The half cells consisting of DC-CCSs retain 93.8% (97.12 mAh g−1) of the initial discharge capacity after 80 cycles, while the bare PE and SC-CCSs exhibit 22.5% and 26.6% capacity retention, respectively. The full cells consisting of DC-CCSs retain 90.9% (102.9 mAh g−1) of the initial discharge capacity after 400 cycles, while the bare PE and SC-CCS exhibit 64.7% and 73.4% capacity retention, respectively.

Developing uniform ceramic-coated separators in high-energy Li secondary batteries has been a challenging task because aqueous ceramic coating slurries have poor dispersion stability and coating quality on the hydrophobic surfaces of polyolefin separators. In this study, we develop a simple but effective strategy for improving the dispersion stability of aqueous ceramic coating slurries by changing the mixing order of the ceramic slurry components. The aqueous ceramic coating slurry comprises ceramics (Al2O3), polymeric binders (sodium carboxymethyl cellulose, CMC), surfactants (disodium laureth sulfosuccinate, DLSS), and water. The interaction between the ceramic slurry components is studied by changing the mixing order of the ceramic slurry components and quantitatively evaluating the dispersion stability of the ceramic coating slurry using a Lumisizer. In the optimized mixing sequence, Al2O3 and DLSS premixed in aqueous Al2O3-DLSS micelles through strong surface interactions, and they repel each other due to steric repulsion. The addition of CMC in this state does not compromise the dispersion stability of aqueous ceramic coating slurries and enables uniform ceramic coating on polyethylene (PE) separators. The prepared Al2O3 ceramic-coated separators (Al2O3–CCSs) exhibit improved physical properties, such as high wettability electrolyte uptake and ionic conductivity, compared to the bare PE separators. Furthermore, Al2O3–CCSs exhibit improved electrochemical performance, such as rate capability and cycling performance. The half cells (LiMn2O4/Li metal) comprising Al2O3–CCSs retain 90.4% (88.4 mAh g−1) of initial discharge capacity after 150 cycles, while 27.6% (26.4 mAh g−1) for bare PE. Furthermore, the full cells (LiMn2O4/graphite) consisting of Al2O3–CCSs exhibit 69.8% (72.2 mAh g−1) of the initial discharge capacity and 24.9% (25.0 mAh g−1) for bare PE after 1150 cycles.

To inhibit Li-dendrite growth on lithium (Li)-metal electrodes, which causes capacity deterioration and safety issues in Li-ion batteries, we prepared a porous polyimide (PI) sponge using a solution-processable high internal-phase emulsion technique with a water-soluble PI precursor solution; the process is not only simple but also environmentally friendly. The prepared PI sponge was processed into porous PI separators and used for Li-metal electrodes. The physical properties (e.g., thermal stability, liquid electrolyte uptake, and ionic conductivity) of the porous PI separators and their effect on the Li-metal anodes (e.g., self-discharge and open-circuit voltage properties after storage, cycle performance, rate capability, and morphological changes) were investigated. Owing to the thermally stable properties of the PI polymer, the porous PI separators demonstrated no dimensional changes up to 180 °C. In comparison with commercialized polyethylene (PE) separators, the porous PI separators exhibited improved wetting ability for liquid electrolytes; thus, the latter improved not only the physical properties (e.g., improved the electrolyte uptake and ionic conductivity) but also the electrochemical properties of Li-metal electrodes (e.g., maintained stable self-discharge capacity and open-circuit voltage features after storage and improved the cycle performance and rate capability) in comparison with PE separators.

Lithium–sulfur (Li–S) batteries are expected to be very useful for next-generation transportation and grid storage because of their high energy density and low cost. However, their low active material utilization and poor cycle life limit their practical application. The use of a carbon-coated separator in these batteries serves to inhibit the migration of the lithium polysulfide intermediate and increases the recyclability. We report the extent to which the electrochemical performance of Li–S battery systems depends on the characteristics of the carbon coating of the separator. Carbon-coated separators containing different ratios of carbon black (Super-P) and vapor-grown carbon fibers (VGCFs) were prepared and evaluated in Li–S batteries. The results showed that larger amounts of Super-P on the carbon-coated separator enhanced the electrochemical performance of Li–S batteries; for instance, the pure Super-P coating exhibited the highest discharge capacity (602.1 mAh g−1 at 150 cycles) with a Coulombic efficiency exceeding 95%. Furthermore, the separators with the pure Super-P coating had a smaller pore structure, and hence, limited polysulfide migration, compared to separators containing Super-P/VGCF mixtures. These results indicate that it is necessary to control the porosity of the porous membrane to control the movement of the lithium polysulfide.

This article explores the implications of captive markets and medical artificial intelligence (AI) in healthcare systems. It discusses how AI companies with large datasets can create captive markets, limiting consumer choice in service providers. The article emphasizes the risks of healthcare institutions relying on a single AI provider and suggests strategies to mitigate these risks, such as promoting interoperability and fostering local AI expertise. It also addresses the importance of data privacy and conflict of interest disclosures when procuring AI services for healthcare systems. The article provides valuable insights into the challenges and considerations of implementing AI in healthcare. [Extracted from the article]