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Four different high-entropy spinel oxide ferrite (HESO) electrode materials containing 5-6 distinct metals were synthesized by a simple, rapid combustion synthesis process and evaluated as conversion anode materials in lithium half-cells. All showed markedly superior electrochemical performance compared to conventional spinel ferrites such as Fe3O4 and MgFe2O4, having capacities that could be maintained above 600 mAh g-1 for 150 cycles, in most cases. X-ray absorption spectroscopy (XAS) results on pristine, discharged, and charged electrodes show that Fe, Co, Ni, and Cu are reduced to the elemental state during the first discharge (lithiation), while Mn is only slightly reduced. Upon recharge (delithiation), Fe is reoxidized to an average oxidation state of about 2.6+, while Co, Ni, and Cu are not reoxidized. The ability of Fe to be oxidized past 2+ accounts for the high capacities observed in these materials, while the presence of metallic elements after the initial lithiation provides an electronically conductive network that aids in charge transfer.

SIGNIFICANCE: Photoacoustic imaging has shown advantages over the periodontal probing method in measuring the periodontal probing depth, but the large size of conventional photoacoustic transducers prevents imaging of the more posterior teeth. AIM: Our aim is to develop a photoacoustic imaging system to image the more posterior periodontal pocket. APPROACH: We report a clinical hockey-stick-style transducer integrated with fibers for periodontal photoacoustic imaging. Cuttlefish ink labeled the periodontal pocket as the photoacoustic contrast agent. RESULTS: We characterized the imaging system and then measured the pocket depth of 35 swine teeth. Three raters evaluated the performance of the hockey-stick transducer. The measurements between the Williams probing (gold standard) and the photoacoustic methods were blinded but highly correlated. We showed a bias of ∼0.3  mm for the imaging-based technique versus Williams probing. The minimum inter-reliability was over 0.60 for three different raters of varying experience, suggesting that this approach to measure the periodontal pocket is reproducible. Finally, we imaged three pre-molars of a human subject. We could access more upper and posterior teeth than conventional linear transducers. CONCLUSIONS: The unique angle shape of the hockey-stick transducer allows it to image more posterior teeth than regular linear transducers. This study demonstrated the ability of a hockey-stick transducer to measure the periodontal pocket via photoacoustic imaging.

The Arctic Ocean experiences significant seasonal to interannual environmental changes, including in temperature, light, sea ice, and surface nutrient concentrations, that influence the dynamics of marine plankton populations. Here, we use a hindcast simulation (1948–2009) of size-structured Arctic Ocean plankton communities, ocean circulation, and biogeochemical cycles in order to better understand how seasonal to interannual changes in the environment influence phytoplankton physiology, plankton community structure, trophic dynamics, and fish production in the Arctic Ocean. The growth of model phytoplankton was primarily limited in winter, spring, and fall by light, but in summer, the growth of smaller and larger phytoplankton was mostly limited by temperature and nutrient availability, respectively. The dominant trophic pathway in summer was from phytoplankton to herbivorous zooplankton such that the average trophic position of model zooplankton was lower in the summer growing season compared to the rest of the year. On interannual timescales, changes in plankton community composition were strongly tied to interannual changes in bottom-up forcing by the environment. In the summer, in years with less ice and warmer temperatures, the biomass of phytoplankton and zooplankton was higher, the size–abundance relationship slopes were more negative (indicative of a phytoplankton community enriched in smaller phytoplankton), zooplankton had higher mean trophic position (indicative of greater carnivory), and potential fishery production was greater, fueled by increased mesozooplankton biomass and flux of organic matter to the benthos. The summertime shift toward greater carnivory in warmer and low-ice years was due primarily to changes in phenology, with phytoplankton and microzooplankton blooms occurring approximately 1 month earlier in these conditions and carnivorous zooplankton increasing in abundance during summer. The model provides a spatially and temporally complete overview of simulated changes in plankton communities in the Arctic Ocean occurring on seasonal to interannual timescales, and it provides insights into the mechanisms underlying these changes as well as their broader biogeochemical and ecosystem significance. [ABSTRACT FROM AUTHOR]

Background There is limited evidence for appropriate postoperative opioid prescribing in autologous breast reconstruction. We sought to describe postoperative outpatient prescription opioid use following discharge after deep inferior epigastric perforator (DIEP) breast reconstruction with and without an educational video. Methods Patients undergoing DIEP reconstruction were given a 28-day postoperative pain and medication logbook from August 2022 to June 2023. Our practice implemented an educational video upon discharge on proper opioid consumption. Descriptive statistics on patient characteristics, intraoperative and postoperative opioid consumption, and outpatient prescription opioid use after discharge were compared between the two cohorts. Results A total of 53 logbooks were completed with 20 patients in the no video cohort and 33 in the video cohort. On average, the days to cessation of opiates was longer in the no video cohort (8.2 vs. 5.1 days, p = 0.003). The average number of oxycodone 5 mg equivalents consumed following discharge was 13.8 in the no video cohort and 7.8 in the video cohort, which was statistically significant (p = 0.01). Overall, the percentage of opioids prescribed that were consumed in the video cohort was 28.3% versus 67.1% in the no video cohort. Conclusion For patients discharging home after DIEP reconstruction, we recommend a prescription for 12 oxycodone 5 mg tablets. With the use of an educational video regarding proper opioid consumption, we were able to reduce the total outpatient opioid use to 5 oxycodone 5 mg tablets following hospital discharge. [ABSTRACT FROM AUTHOR]

Lithium- and manganese-rich oxides are of interest as lithium-ion battery cathode materials as Mn is earth abundant, low cost, and can deliver high capacity. Herein, a high entropy strategy was used to prepare Mn rich high entropy oxide (HEO) materials by including four additional metals (Ni, Co, Fe and Al) in the compositions using a mild co-precipitation method. Two HEOs (LixNi0.1Mn0.6Co0.1Al0.1Fe0.1Oy, where x = 1.5 for HEO-L and x = 0.5 for HEO-H) with layered and spinel-layered hybrid structures were investigated where the morphology, elemental composition, structure, atomic level phase distribution, and electrochemistry were determined. The HEO-L samples involve a Li2TMO3 layered structure with ∼39% stacking faults. HEO-H is a hybrid structure comprised of 80 wt% spinel and 20 wt% LiMO2 layered structure. The high entropy manganese-rich HEO-L showed higher capacity and 93% retention of the average voltage after 100 cycles while HEO-H showed higher capacity retention and near 100% average voltage retention. Operando X-ray absorption spectroscopy revealed that the Ni, Co, and Mn are redox active in both materials while the Fe center remains at the Fe3+ oxidation state throughout cycling, where the changes in the oxidation states for both materials during discharge were consistent with the delivered electrochemical capacity rationalizing the observed electrochemistry. [ABSTRACT FROM AUTHOR]

Case: An overall healthy 48-year-old man suffered a left foot mangled crush injury resulting in a post-transmetatarsal amputation and subsequently developing a painful neuroma on the plantar surface of the foot. To avoid the zone of injury, targeted muscle reinnervation was used to treat the neuroma by coapting the tibial nerve to the motor point of the flexor hallucis longus (FHL) muscle. At 1-year follow-up, the patient reported no pain at rest, returned to work, and could ambulate with an orthosis for 30 minutes. Conclusion: Rare tibial nerve coaptations to the FHL could serve as a treatment option for patients with neuromas in traumatic postmetatarsal amputation. [ABSTRACT FROM AUTHOR]

In marine ecosystems, most physiological, ecological, or physical processes are size-dependent. These include metabolic rates, uptake of carbon and other nutrients, swimming and sinking velocities, and trophic interactions, which eventually determine the stocks of commercial species, as well as biogeochemical cycles and carbon sequestration. As such, broad scale observations of plankton size distribution are important indicators of the general functioning and state of pelagic ecosystems under anthropogenic pressures. Here, we present the first global datasets of the Pelagic Size Structure database (PSSdb), generated from plankton imaging devices. This release includes the bulk particle Normalized Biovolume Size Spectrum (NBSS) and bulk Particle Size Distribution (PSD), along with their related parameters (slope, intercept, and R2) measured within the epipelagic layer (0-200 m) by three imaging sensors: the Imaging FlowCytobot (IFCB), the Underwater Vision Profiler (UVP) and benchtop scanners. Collectively, these instruments effectively image organisms and detrital material in the 7-10,000 µm size range. A total of 92,472 IFCB samples, 3,068 UVP profiles, and 2,411 scans passed our quality control and were standardized to produce consistent instrument-specific size spectra averaged in 1x1° latitude/longitude, and by year and month. Our instrument-specific datasets span all major ocean basins, except for the IFCB which was exclusively deployed in northern latitudes, and cover decadal time periods (2013-2022 for IFCB, 2008-2021 for UVP, and 1996-2022 for scanners), allowing for a further assessment of the pelagic size spectrum in space and time. [ABSTRACT FROM AUTHOR]