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Abstract Texturing the battery electrode to create low‐tortuosity ordered structures can significantly improve the sluggish mass transport in thick electrodes (areal mass loading>20 mg/cm²) during the energy storage electrochemical reactions. In this work, we presented an efficient and effective method to regulate the electrode structure by creating aligned channels throughout the thickness of the electrode. The method combines acoustic manipulation of particles and nonsolvent induced phase inversion and is highly compatible with a wide range of materials used in various battery chemistries. The textured electrodes show better structural integrity compared to electrodes of similar mass loading made with acoustic patterning only and with conventional solution casting. Compared with electrodes made with phase inversion only, it exhibits lower tortuosity, enhanced ion transport/kinetics, better rate capability and cyclic stability. 

An acoustic particle patterning method generated ordered structures in battery electrodes to facilitate lithium-ion diffusion and charge transport kinetics, allowing superior rate capability and cycling stability over conventional electrodes. 

The pain felt during injection, typically delivered via a hypodermic needle as a single bolus, is associated with the pressure build-up around the site of injection. It is hypothesized that this counterpressure is a function of the target tissue as well as fluid properties. Given that novel vaccines target different tissues (muscle, adipose, and skin) and can exhibit a wide range of fluid properties, we conducted a study of the effect of volumetric flow rate, needle size, viscosity and rheology of fluid, and hyaluronidase as an adjuvant on counterpressure build-up in porcine skin and muscle tissues. In particular, we found a significant increase in counterpressure for intradermal (ID) injections compared to intramuscular (IM) injections, by an order of magnitude in some cases. We also showed that the addition of adjuvant affected the tissue back pressure only in case of subcutaneous (SC) injections. We observed that the volumetric flow rate plays an important role along with the needle size. This study aims to improve the current understanding and limitations of liquid injectability via hypodermic needles, however, the results also have implications for other technologies, such as intradermal jet injection where a liquid bleb is formed under the skin. 

Abstract We present results from a search for X-ray/gamma-ray counterparts of gravitational-wave (GW) candidates from the third observing run (O3) of the LIGO–Virgo–KAGRA network using the Swift Burst Alert Telescope (Swift-BAT). The search includes 636 GW candidates received with low latency, 86 of which have been confirmed by the offline analysis and included in the third cumulative Gravitational-Wave Transient Catalogs (GWTC-3). Targeted searches were carried out on the entire GW sample using the maximum-likelihood Non-imaging Transient Reconstruction and Temporal Search pipeline on the BAT data made available via the GUANO infrastructure. We do not detect any significant electromagnetic emission that is temporally and spatially coincident with any of the GW candidates. We report flux upper limits in the 15–350 keV band as a function of sky position for all the catalog candidates. For GW candidates where the Swift-BAT false alarm rate is less than 10⁻³Hz, we compute the GW–BAT joint false alarm rate. Finally, the derived Swift-BAT upper limits are used to infer constraints on the putative electromagnetic emission associated with binary black hole mergers. 

Abstract Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame massM> 70M_⊙) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 <e≤ 0.3 at 16.9 Gpc⁻³yr⁻¹at the 90% confidence level. 

Abstract Gravitational lensing by massive objects along the line of sight to the source causes distortions to gravitational wave (GW) signals; such distortions may reveal information about fundamental physics, cosmology, and astrophysics. In this work, we have extended the search for lensing signatures to all binary black hole events from the third observing run of the LIGO-Virgo network. We search for repeated signals from strong lensing by (1) performing targeted searches for subthreshold signals, (2) calculating the degree of overlap among the intrinsic parameters and sky location of pairs of signals, (3) comparing the similarities of the spectrograms among pairs of signals, and (4) performing dual-signal Bayesian analysis that takes into account selection effects and astrophysical knowledge. We also search for distortions to the gravitational waveform caused by (1) frequency-independent phase shifts in strongly lensed images, and (2) frequency-dependent modulation of the amplitude and phase due to point masses. None of these searches yields significant evidence for lensing. Finally, we use the nondetection of GW lensing to constrain the lensing rate based on the latest merger-rate estimates and the fraction of dark matter composed of compact objects.