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This paper proposes a sequential delay-free strategy to avoid side effects of the delays arising from both analog and digital implementations of permanent magnet synchronous machine (PMSM) drives on the accuracy of sliding mode position observers used in the high-speed conditions. First, after establishing the sliding mode observer (SMO) used for position estimation, the principles of the analog delay, low-pass filter (LPF) delay and execution delay together with their impacts are presented at length, posing the necessity of investigating the delay-free techniques. Then, novel current-based, position-based and speed-prediction-based compensation strategies are developed to deal with the three kinds of delays, respectively. Because the proposed compensation strategies are achieved based on the direct signal compensation theories, they are simple to be understood and implemented in practice. Third, the implementation sequence of the sequential delay compensation-based SMO is illustrated clearly. Thanks to the proposed delay compensation approaches, not only the position estimation accuracy but also the current regulation process of the closed-loop control can be improved. Finally, experiment is conducted on a three-phase 8000 rpm PMSM to verify the effectiveness of the proposed delay compensation-based SMO algorithms. [ABSTRACT FROM AUTHOR]

In this work, self‐derivation and surface reconstruction strategies are innovatively introduced into the synthetic route of the metal complex‐derived catalysts. The in situ grown nanorod arrays of Ni‐based complex are prepared by a simple self‐derivation and rapid ligand chelation reaction. Furthermore, highly active heterogeneous electrocatalysts are developed by mild‐temperature calcination. Attributed to the maintained morphology and highly dispersed Ni/Ni(OH)2 heterojunction active sites, the as‐prepared electrode exhibits superior hydrogen evolution activity (38.4 mV–10 mA cm−2). In particular, the dynamic reconstruction during oxygen evolution through in situ Fourier transform infrared and in situ Raman spectroscopies are observed. The reconstructed Ni(OH)2/NiOOH by activation gives the electrode higher oxygen evolution performance (369 mV–200 mA cm−2). Further density functional theory mechanism studies disclose that Ni/Ni(OH)2 contributes to the adsorption of H* in hydrogen evolution and the activated Ni(OH)2/NiOOH optimizes the formation of intermediates in oxygen evolution. [ABSTRACT FROM AUTHOR]

As urban populations grow, the problem of noise pollution becomes more significant. The limited number of epidemiological studies linking individual-level dynamic noise exposure to sleep highlights a gap in our understanding of how individual-level noise exposure impact sleep quality and duration. A cross-sectional survey was conducted in Hong Kong, and portable noise sensors were used to record participants' real-time noise exposure. The Pittsburgh Sleep Quality Index was used to assess their sleep quality. Logistic regression was used to examine the relationship of individual-level noise exposure with sleep quality and sleep duration. Among a total of 763 subjects included in the analysis, and a-weighted decibels [dB(A)] 24-h average exposure (L 24 ) was 63.21 (58.85-67.85) dB(A) for workday and 63.52 (59.03-67.86) dB(A) for non-workday. A significant decrease in individual noise level was observed closer to bedtime (P < 0.05). Compared with the lowest noise exposure, exposure to the highest noise level was positively associated with the presence of poor sleep quality for L 24 , L d and L n , with an odds ratio (OR) and 95 % confidential interval (CI) of 1.53 (1.04-2.24), 1.65 (1.12-2.43), and 1.51 (1.03-2.21), respectively. Exposure to elevated noise level was associated with increased risk of shorter nocturnal sleep duration (< 7 h), the OR and 95 % CI was 1.87 (1.29-2.73) for L 24 , 1.58 (1.09-2.30) for L d , 1.50 (1.03-2.18) for L e , and 1.60 (1.10-2.32) for L n in the highest noise exposure group. Similar findings were observed both on workdays and non-workdays, respectively. Furthermore, the results showed that each 10 dB(A) increment in L 24 and L n was associated with a probable 29 % and 27 % increase in poor sleep quality and a 24 % and 24 % reduction in sleep duration. This study demonstrates that environmental noise exposure was associated with poor sleep quality and shorter sleep duration, posing a significant public health issue in Hong Kong., (Copyright © 2024. Published by Elsevier B.V.)

Background: No study explored the association of noise exposure in the workplace and genetic susceptibility with incidence of atrial fibrillation (AF). We aimed to assess the separate and joint relationship of noise exposure in the workplace and genetic susceptibility with the risk of AF., Methods and Results: We included 167 577 participants without AF at baseline in UK Biobank. Cox proportional hazards models were used to assess the separate and joint association of noise exposure in the workplace and genetic susceptibility with the risk of AF. During a median follow-up of 11.83 years, we observed 9355 AF cases. Compared with no noise exposure in the workplace, the hazard ratios (HRs) and were 1.08 (95% CI, 0.99-1.18) for noise exposure in the workplace of <1 year, 1.03 (95% CI, 0.95-1.12) for noise exposure in the workplace of around 1 to 5 years, and 1.08 (95% CI, 1.02-1.14) for noise exposure in the workplace of >5 years, respectively, after adjusting for potential confounders. Genetic risk was positively associated with AF, compared with low genetic risk (tertile 1), the HRs were 1.50 (95% CI, 1.41-1.59) for medium genetic risk (tertile 2) and 2.51 (95% CI, 2.38-2.65) for high genetic risk (tertile 3). However, no interaction between noise exposure in the workplace and genetic susceptibility was observed ( P >0.05)., Conclusions: Long-term noise exposure in the workplace is positively associated with a higher incidence of AF regardless of genetic background.

Background: The relationship between vitamin D and depression has garnered significant attention in recent years. However, the efficacy of vitamin D in ameliorating depression among specific subgroups of older patients remains controversial. This study aimed to assess the impact of vitamin D supplementation on depressive symptoms and the prevalence of depression in older adults. Additionally, the study sought to examine potential moderating factors, including differences among population subgroups and various supplementation strategies., Methods: A systematic literature search was conducted in the databases PubMed, EMBASE, Web of Science, and the Cochrane Library up to March 2024. The RevMan 5.3 software was utilized to calculate the standardized mean difference (SMD) and to evaluate the quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. The objective was to determine the efficacy of vitamin D supplementation in alleviating depressive symptoms or treating depression in older adults., Results: This meta-analysis encompassed eleven studies, comprising a total of 21,561 participants. The findings did not indicate a statistically significant therapeutic benefit of vitamin D supplementation for depression in older patients [SMD: -0.10; 95% CI: (-1.19, 0.00); p  = 0.05]. Subgroup analyses revealed that the efficacy of vitamin D intervention in geriatric depression correlated with several factors, including baseline serum 25(OH)D levels, the dosage of the intervention, gender, and the initial presence of depressive symptoms or a diagnosis of depression., Conclusion: The current evidence is insufficient to conclusively establish the significant efficacy of vitamin D supplementation in alleviating depressive symptoms among older patients. Consequently, additional randomized controlled trials are warranted to further validate the relationship between vitamin D supplementation and depression in the older adults., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Fu, Zhang, Chen, Yu, Yan, Jing, Yu, Li and Guo.)

Objective: We aimed to explore the role of connexin26 (Cx26) and connexin30 (Cx30) in the cochlea in noise-induced permanent threshold shifts (PTS) and temporary threshold shift (TTS)., Study Design: Prospective, controlled., Setting: Laboratory., Methods: A mouse model of noise-induced PTS and TTS was constructed. Western blots were used to detect the expression of Cx26 and Cx30 in the cochlea. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to assess the potential biological pathways., Results: Both the expression of Cx26 and Cx30 showed a trend of first rising and then falling in noise-induced PTS. The expression of Cx26 increased greatly in the 24 hours noise exposure (P < .05) and reached the highest level in the 4 hours after noise exposure (P < .05), then decreased gradually and returned to the control level on the seventh day after the noise exposure, when compared with the control group. The expression of Cx30 showed a similar trend in noise-induced PTS. However, both the expression of Cx26 and Cx30 showed a trend of first falling and then rising in noise induced TTS. The expression of Cx26/Cx30 reached its lowest level in the 4 hours after noise exposure (P < .05), and then increased to the control level on the second day after noise exposure (P > .05), compared with the control group. The first KEGG and GO pathway may be related with oxidative phosphorylation., Conclusion: Cx26 and Cx30 may have an effect in noise induced PTS and TTS. Future studies are needed to confirm the results., (© 2024 American Academy of Otolaryngology–Head and Neck Surgery Foundation.)

Single-atom catalysis is a subcategory of heterogeneous catalysis with well-defined active sites. Numerous endeavors have been devoted to developing single-atom catalysts for industrially applicable catalysis, including the hydrogen evolution reaction (HER). High-current-density electrolyzers have been pursued for single-atom catalysts to increase active-site density and enhance mass transfer. Here, we reasoned that a single-atom metal embedded in nitrogen assembly carbon (NAC) catalysts with high single-atom density, large surface area, and ordered mesoporosity, could fulfil an industrially applicable HER. Among several different single-atom catalysts, the HER overpotential with the best performing Co-NAC reached a current density of 200 mA cm -2 at 310 mV, which is relevant to industrially applicable current density. Density functional theory (DFT) calculations suggested feasible hydrogen binding on single-atom Co resulted in the promising HER activity over Co-NAC. The best-performing Co-NAC showed robust performance under alkaline conditions at a current density of 50 mA cm -2 for 20 h in an H-cell and at a current density of 150 mA cm -2 for 100 h in a flow cell.

Cladding-pumped multicore erbium-doped fiber is an important element for future spatial division multiplexing (SDM) amplification. We propose an M-type erbium-doped multicore fiber to achieve high-efficiency SDM amplification. The performance of cladding-pumped erbium-doped fiber with a central refractive index depression has been investigated, and the M-type fiber has better amplification performance than conventional fibers by reducing the signal mode overlap with the doped region. The experiment results show that the M-type 4-core erbium-doped fiber has a gain improvement of 2.8 dB compared with conventional 4-core fiber. The pump conversion efficiency (PCE) has been enhanced from 4.47% to 8.01%. For a 7.0 W pump power at 976 nm, the M-type fiber exhibits an average gain of 20.0 dB and an average noise fiber of 6.8 dB at the L-band. The core-to-core gain variation is less than 1.6 dB.

Extending the gain bandwidth of L-band optical fiber amplifier has provoked a widespread interest. To date, achieving a high-efficiency extended L-band amplification remains a challenge. Here, we report a cladding-pumped Er/Yb co-doped alumino-phosphosilicate fiber, prepared by the modified chemical vapor deposition process. We demonstrate the efficiency of alumino-phosphosilicate glass for cladding-pumped Er/Yb co-doped fiber, with a gain per unit fiber length of 0.45 dB/m at 1625 nm and a gain ripple of ∼9.4 dB. For 0.8 W pump power, the fiber exhibits a 20 dB gain bandwidth covering 1575-1625 nm and 6.9 dB noise figure at 1625 nm. Additionally, the utilization of multi-mode laser diode enables further significant power savings and cost reduction. To the best of our knowledge, Er/Yb co-doped fiber in alumino-phosphosilicate glass is first proposed, with a cladding-pumped scheme for enhancing an extended L-band performance.

The application of therapeutic peptides in clinical practice has significantly progressed in the past decades. However, immunogenicity remains an inevitable and crucial issue in the development of therapeutic peptides. The prediction of antigenic peptides presented by MHC class II is a critical approach to evaluating the immunogenicity of therapeutic peptides. With the continuous upgrade of algorithms and databases in recent years, the prediction accuracy has been significantly improved. This has made in silico evaluation an important component of immunogenicity assessment in therapeutic peptide development. In this review, we summarize the development of peptide-MHC-II binding prediction methods for antigenic peptides presented by MHC class II molecules and provide a systematic explanation of the most advanced ones, aiming to deepen our understanding of this field that requires particular attention., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)