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Objective: Osteoporosis is prevalent in patients with chronic kidney disease (CKD), with risk increasing as CKD progresses, subsequently elevating fracture risk. While previous studies have shown a link between low skeletal muscle mass and osteoporosis in the general population, there is limited research exploring this relationship in patients with advanced CKD (stages 3-5D). This study aimed to evaluate whether skeletal muscle area (SMA), as measured by abdominal CT, is correlated with bone mineral density (BMD) in advanced CKD patients beginning hemodialysis. Methods: This single-center, retrospective cohort study included patients who started maintenance hemodialysis at Daejeon St. Mary's Hospital from January 2018 to September 2021. Patients who underwent abdominal CT and BMD assessments within three months of dialysis initiation were enrolled, resulting in a sample of 87 individuals. Baseline characteristics were analyzed, with patients stratified by sex and SMA quartiles. Pearson's correlation and multivariate regression analyses were conducted to the relationship between SMA and BMD T-scores. Results: The study cohort had an average age of 65.4 years, with 52.9% of participants being male. Male patients exhibited significantly higher SMA and BMD T-scores in both the lumbar spine and femur compared to female patients. SMA showed the strongest positive correlation with BMD at both sites (lumbar spine, r = 0.424; femur, r = 0.514; p < 0.001). Multivariate analysis identified SMA as an independent positive predictor of BMD, while alkaline phosphatase (ALP) was independently associated with lower femur BMD. In the SMA-based subgroup analysis, patients with lower SMA had significantly lower BMD T-scores and a higher risk of osteoporosis. Logistic regression indicated that patients in the lowest SMA quartile had substantially increased odds of osteoporosis compared to those in the highest quartile, with an adjusted odds ratio of 30.59 (p = 0.008). Conclusions: Lower skeletal muscle mass is significantly associated with lower bone density and a higher risk of osteoporosis in advanced CKD patients initiating hemodialysis. SMA, as measured by abdominal CT, may serve as a useful marker for identifying patients at elevated osteoporosis risk in this population. [ABSTRACT FROM AUTHOR]

Solid electrolyte containing mobile alkaline ions is a key component in all-solid-state rechargeable batteries. In this work, a relatively new Na+-conducting solid electrolyte, Na3ZnGaS4, is investigated for a significant increase in ionic conductivity (σion) to a reasonable level. An adjustment in the Zn/Ga ratio results in vacancy formation in Na(2) sites, which leads to a steep increase in σion and to a simultaneous decrease in activation energies (0.32 mS cm−1 and 0.30 eV for hot-pressed Na2.8Zn0.8Ga1.2S4 at 30 °C). This strategy is ineffective in Na3ZnGaSe4, which possesses pre-existing vacancy defects. The preferential formation of vacancies in mobile Na(2), possibility for further improvement of σion, and excellent electrochemical stability are theoretically and experimentally verified. The perfect inertness of Na2.8Zn0.8Ga1.2S4 in aqueous dispersions (neither decomposition nor hydration) is also confirmed, which suggests that the vacancy-incorporated Na3−xM(II)1−xM(III)1+xS4 could be a promising class of Na+-conducting electrolytes. [ABSTRACT FROM AUTHOR]

Anode-free Li-ion batteries (AFLIBs) are regarded as among the most promising Li-based batteries for quantum leaps in energy densities. However, despite extensive efforts, the performance of AFLIBs is still in its infancy, requiring striking improvement, particularly in cycle stability. This study shows for the first time that carbon cloth (CC) can embody viable AFLIBs with unprecedented cyclability. In contrast to other carbonaceous substrates, CC with a cross-aligned weave pattern enables the immediate formation of a thin, uniform solid-electrolyte-interface (SEI) layer, which is robust during subsequent charge/discharge cycles. Li plating/stripping through stable SEI layers is also nearly perfectly reversible with no sign of dendrites owing to the increased Li+ flux and facilitated nucleation on CC. Consequently, when SEI-formed CC (i.e., CC in a reduced state with Li+ ions inserted) is coupled with LiFePO4 in conventional carbonate electrolytes, Li+ ions released from LiFePO4 are not consumed by side reactions, Li+ ions inserted in SEI-formed CC remain intact, and AFLIBs exhibit unprecedented long-term cyclability with no short circuit. The capacity retention amounts to 91.00% for 3000 charge/discharge cycles with an average coulombic efficiency of 99.94%, which is incomparably high compared to the best performance of AFLIBs reported to date (80% after 195 cycles). The results of the study are expected to provide an innovative idea for the development of commercial AFLIBs. [ABSTRACT FROM AUTHOR]

Na3PS4 is an archetypal room-temperature (RT), Na+-conducting, solid-state electrolyte. Various compositional modifications of this compound via iso/aliovalent substitution are known to provide a high ionic conductivity (σion) that is comparable to that of liquid electrolytes. In this work, we implemented a Bayesian optimization (BO) algorithm to discover new compositions with a high σion in a multi-dimensional search space. BO has attracted a great deal of attention in materials research since it is successfully used as a closed-loop optimization strategy for materials discovery. The systematically designed search space used for our BO implementation consisted of compositional variables (A = Ca2+, Y3+, La3+; M1 = P5+, Sb5+; M2 = Si4+, Ge4+, Sn4+; Q = S2−, Se2−, Te2−; X = Cl−, Br−, I− in (Na, A)3δ(M1, M2, W)(Q, X)4) and processing variables (synthetic temperature and time). Na2.81(W0.22Si0.10Sb0.68)S3.93Br0.07 selected through BO was further refined via logical reasoning. Subsequently, Br-free Na2.88(W0.22Si0.10Sb0.68)S4 was discovered. Heavily co-doped Na3SbS4 by Si4+ and W6+ show high σion (20.2 and 7.4 mS cm−1) at RT and −20 °C, respectively, which can be ascribed to the notably low activation barrier (0.14 eV) in the Na3PS4 family. Herein, a low electronic conductivity (2 × 10−7 S cm−1) and stable Na plating/stripping is also discussed. These types of behavior suggest that Na2.88(W0.22Si0.10Sb0.68)S4 could be a promising solid-state electrolyte (SSE) of the Na3PS4 family. [ABSTRACT FROM AUTHOR]

This article presents a highly integrated CMOS RF double-sideband (DSB) transmitter (TX) including an active input balun and a single-ended power amplifier (PA) for a ultrahigh frequency radiofrequency identification (RFID) system-on-chip reader. The conventional TX architecture, including an up-conversion mixer and a balanced PA, requires an output balun to create the needed single-ended load. Compared to the conventional TX architecture, the proposed system provides a more compact circuit and uses a smaller chip area because the active balun and the single-ended PA have a much smaller size than those using a passive balun and a differential PA. In addition, the gain of the active balun, which is generally larger than unity, can be a benefit in the system design budget. The designed TX IC is fabricated using a 0.13 μm CMOS process on a small area of 780 × 560 μm2 (including pads). The TX IC exhibited an overall conversion gain of 41.7 dB, an output P1dB of 18 dBm, an OIP3 of 28 dBm, a DSB noise figure of 14.8 dB, and a power consumption of 284.4 mW, including the 42.9 mW consumed by the local oscillator buffer stages. The implemented TX IC complied with the spectral mask for the DSB amplitude-shift keying signal of the RFID reader at an output power of 15.5 dBm. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:205-210, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27257 [ABSTRACT FROM AUTHOR]