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Improvements in both the power and energy density of lithium-ion batteries (LIBs) will enable longer driving distances and shorter charging times for electric vehicles (EVs). The use of thicker and denser electrodes reduces LIB manufacturing costs and increases energy density characteristics at the expense of much slower Li-ion diffusion, higher ionic resistance, reduced charging rate, and lower stability. Contrary to common intuition, we unexpectedly discovered that removing a tiny amount of material (<0.4 vol %) from the commercial electrodes in the form of sparsely patterned conical pores greatly improves LIB rate performance. Our research revealed that upon commercial production of high areal capacity electrodes, a very dense layer forms on the electrode surface, which serves as a bottleneck for Li-ion transport. The formation of sparse conical pore channels overcomes such a limitation, and the facilitated ion transport delivers much higher power without reduction in the practically attainable energy. Diffusion and finite element method-based simulations provide deep insights into the fundamentals of ion transport in such electrode designs and corroborate the experimental findings. The reported insights provide a major thrust to redesigning automotive LIB electrodes to produce cheaper, longer driving range EVs that retain fast charging capability., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

We report on a new synthesis pathway for Mg n -propoxide nanowires (NWs) from Mg ethoxide nanoparticles using a simple alkoxy ligand exchange reaction followed by condensation polymerization in n -propanol. In order to uncover the morphology-structure correlation in the metal alkoxide family, we employed a powerful range of state-of-the-art characterization techniques. The morphology transformation from nanoparticles to nanowires was demonstrated by time-lapse SEM micrographs. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (such as 1 H NMR and solid-state 13 C cross-polarization (CP)-MAS NMR) illustrated the replacement of ethyl by n -propyl and metal alkoxide condensation polymerization. We identified chemical formulas of the products also using NMR spectroscopy. The crystal structure simulation of Mg ethoxide particles and Mg n -propoxide NWs provided insights on how the ligand exchange and the associated increase in the fraction of OH groups greatly enhanced Mg alkoxide bonding and enabled a higher degree of coordination polymerization to facilitate the formation and growth of the Mg n -propoxide NWs. The discovered synthesis method could be extended for the fabrication of other metal alkoxide (nano) structures with various morphologies.

Natural killer (NK) cells serve as key innate effectors and their activity has been considered a prognostic biomarker in diverse human diseases. Currently, NK cell functional assays have several problems primarily related to adequate preparation, labeling, or treatment of target cells, which are cumbersome and often hamper consistent sensitivity for NK cells. Here, bispecific antibodies (BsAb's) targeting NKG2D and 2B4 receptors, whose combination mounts selective cytotoxicity and IFN-γ production of NK cells, are developed as acellular, consistent, and easy-to-use strategies for assessing NK cell functions. These NK cell activator BsAb's (NKABs) are constructed in symmetric dual bivalent formats with different interdomain spacings [immunoglobulin G (IgG)-single-chain variable fragment (scFv) and dual-variable domain (DVD)-Ig] and kappa constant (Cκ)-scFv format linking two scFv's with a Cκ domain. These NKABs are specific and superior to a combination of monospecific antibodies for NK cell activation. NKAB elicits both direct cytotoxicity and IFN-γ production via integration of NKG2D and 2B4 signals. Moreover, stimulation with NKAB IgG-scFv and Cκ-scFv reveals defective NK cell functions in X-linked lymphoproliferative disease involving 2B4 dysfunction in NK cells and multiple myeloma in peripheral blood mononuclear cells and whole blood, respectively. Hence, this work provides a proof of concept that NKAB facilitates the reliable and comprehensive measurement of NK cell function in clinical settings for diagnostic and prognostic purposes.

Natural killer (NK) cells are a subset of innate lymphoid cells playing an important role in immune surveillance and early defense against infection and cancer. They recognize and directly kill infected or transformed cells. At the same time, they produce various cytokines and chemokines to regulate other immune cells. NK cell activity can be a useful marker for health screenings because impaired NK cell functions may indicate a more susceptible environment for infection or tumor development. Currently, most NK cell activity assays are focused on measuring either cytokine secretion, in particular, interferon γ (IFN-γ), or cytotoxicity against target cells such as K562, thus only providing partial information on NK cell activity. In order to develop a comprehensive test for measuring NK cell function, cytotoxicity and cytokine secretion ability should be measured simultaneously. In addition, current NK cell assays are performed by stimulating NK cells with cocktails of cytokines, antibody-coated beads, or live target cells. In this study, we developed multifunctional microparticles for NK cell activity assay (MNAs) that allow simultaneous stimulation and sensing various NK cell activities, including cytokine secretion and cytotoxicity. The surfaces of MNAs are decorated with multiple functional biomolecules, including antibodies that stimulate NK cells by engaging NK cell activating receptors, antibodies that can capture cytokines secreted by NK cells, and a peptide sensor that reacts with granzyme B, a key molecule released by NK cells for cytotoxicity. The performances of MNAs are assessed using flow cytometry and live cell imaging. NK cell activity is measured by simply mixing MNAs with NK cells and performing flow cytometry, and the results are comparable to those measured by standard NK cell activity assays.

Fabrication and applications of lightweight, high load-bearing, thermally stable composite materials would benefit greatly from leveraging the high mechanical strength of ceramic nanowires (NWs) over conventional particles or micrometer-scale fibers. However, conventional synthesis routes to produce NWs are rather expensive. Recently we discovered a novel method to directly convert certain bulk bimetallic alloys to metal-organic NWs at ambient temperature and pressure. This method was demonstrated by a facile transformation of polycrystalline aluminum-lithium (AlLi) alloy particles to aluminum alkoxide NWs, which can be further transformed to mechanically robust aluminum oxide (Al 2 O 3 ) NWs. However, the transformation mechanisms have not been clearly understood. Here, we conducted advanced materials characterization (via electron microscopy and nuclear magnetic resonance spectroscopies) and chemo-mechanical modeling to elucidate key physical and chemical mechanisms responsible for NWs formation. We further demonstrated that the content of Li metal in the AlLi alloy could be reduced to about 4 wt % without compromising the success of the NWs synthesis. This new mechanistic understanding may open new avenues for large-scale, low-cost manufacturing of NWs and nanofibers for a broad range of composites and flexible ceramic membranes.