High-temperature high-sensitivity AlN-on-SOI Lamb wave resonant strain sensor

A piezoelectric AlN-on-SOI structured MEMS Lamb wave resonator (LWR) is presented for high-temperature strain measurement. The LWR has a composite membrane of a 1 μm thick AlN film and a 30 μm thick device silicon layer. The excited acoustic waves include Rayleigh wave and Lamb waves. A tensile strain sensor has been prepared with one LWR mounted on a uniaxial tensile plate, and its temperature characteristics from 15.4°C to 250°C and tensile strain behaviors from 0 μϵ to 400 μϵ of Rayleigh wave and S4 mode Lamb wave were tested. The temperature test verifies the adaptability of the tensile strain sensor to temperature up to 250°C, and S4 mode Lamb wave and Rayleigh wave represent almost the same temperature characteristics. The strain test demonstrates that S4 mode Lamb wave shows much higher strain sensitivity (-0.48 ppm/μϵ) than Rayleigh wave (0.05 ppm/μϵ) and confirms its advantage of strain sensitivity. Finally, for this one-LWR strain sensor, a method of beat frequency between S4 mode Lamb wave and Rayleigh wave is proposed for temperature compensation and high-sensitivity strain readout

Fine-Tuning LUMO Energy Levels of Conjugated Polymers Containing a B←N Unit

The LUMO and HOMO energy levels (<i>E</i>_LUMO/<i>E</i>_HOMO) are key parameters for conjugated polymers, which can greatly affect their applications in organic opto-electronic devices. In this manuscript, with donor–acceptor (D–A) type conjugated polymers based on double B←N bridged bipyridine (BNBP) unit, we report fine-tuning of <i>E</i>_LUMO of conjugated polymers in a wide range via substitutions on both D unit and A unit. We synthesize eight D–A type conjugated polymers with alternating electron-deficient BNBP unit and electron-rich bithiophene (BT) unit in the main chain. By changing the substitutes on BNBP or BT, the <i>E</i>_LUMO of these polymers can be finely tuned in a wide range from −3.3 eV to −3.7 eV. We comprehensively investigate the electronic structures, photophysical properties, charge-transporting properties and polymer solar cell (PSC) device applications of these polymers. In PSC devices, these BNBP-based polymers can be used either as electron donors (with high-lying <i>E</i>_LUMO/<i>E</i>_HOMO) or as electron acceptors (with low-lying <i>E</i>_LUMO/<i>E</i>_HOMO). The PSC device with the BNBP-based polymer donor exhibits a PCE of 2.92% and the PSC device with the BNBP-based polymer acceptor exhibits a PCE of 5.16%. These results indicate a new approach to modulate the LUMO energy levels of D–A type conjugated polymers by modifications on both D unit and A unit

Comparison between the Mesospheric Winds Observed by Two Collocated Meteor Radars at Low Latitudes

This study compares the hourly mesospheric horizontal winds observed by two collocated and independent low-latitude meteor radars operating at 37.5 MHz and 53.1 MHz in Kunming, China (25.6°N, 103.8°E). Upon analyzing simultaneously detected meteor echoes, we find a fixed angular deviation between the baselines of the two meteor radar antenna arrays within the east–north–up coordinate system. Then, we correct the deviation in the antenna azimuth direction using a novel method and recalculate the horizontal zonal and meridional winds. A comparison of the results before and after the correction shows strong consistency between the winds observed by both meteor radars within the entire detection altitude range. Furthermore, we summarize the performance of different techniques for measuring mesospheric winds. Ultimately, our statistical analysis approach allows the uncertainties associated with meteor radar wind observations to be more precisely estimated

Security event-trigger-based distributed energy management of cyber-physical isolated power system with considering nonsmooth effects

Due to cyber-physical fusion and nonsmooth characteristics of energy management, this article proposes a security event-trigger-based distributed approach to address these issues with developed smoothing technique. To tackle with nonconvex and nondifferentiable issue, a randomized gradient-free-based successive convex approximation is developed to smooth economic objective function. Due to resilience ability against security issue, a security event-triggered mechanism-based distributed energy management is proposed to optimize social welfare, which coordinately controls both power generators and load demand. The security event-triggered mechanism is designed to reduce power system security risks, and relieve communication burden caused by smoothing calculation, the convergence of proposed distributed algorithm is also properly proved. According to those obtained results on both IEEE 9-bus and IEEE 39-bus systems, it reveals that the proposed approach can achieve good convergence performance and have less security risks than other alternatives, which also proves that the proposed approach can be a viable and promising way for tackling with energy management issue of cyber-physical isolated power system.National Natural Science Fund, Basic Research Project of Leading Technology of Jiangsu Province, National Natural Science Fund of Jiangsu Province.https://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=6221036hj2023Electrical, Electronic and Computer EngineeringSDG-07:Affordable and clean energySDG-09: Industry, innovation and infrastructur

Drug-loaded microbubble delivery system to enhance PD-L1 blockade immunotherapy with remodeling immune microenvironment

Abstract Background Although programmed cell death protein 1 (PD-1)/ programmed cell death-ligand protein 1 (PD-L1) checkpoint blockade immunotherapy demonstrates great promise in cancer treatment, poor infiltration of T cells resulted from tumor immunosuppressive microenvironment (TIME) and insufficient accumulation of anti-PD-L1 (αPD-L1) in tumor sites diminish the immune response. Herein, we reported a drug-loaded microbubble delivery system to overcome these obstacles and enhance PD-L1 blockade immunotherapy. Methods Docetaxel (DTX) and imiquimod (R837)-loaded microbubbles (RD@MBs) were synthesized via a typical rotary evaporation method combined with mechanical oscillation. The targeted release of drugs was achieved by using the directional "bursting" capability of ultrasound-targeted microbubble destruction (UTMD) technology. The antitumor immune response by RD@MBs combining αPD-L1 were evaluated on 4T1 and CT26 tumor models. Results The dying tumor cells induced by DTX release tumor-associated antigens (TAAs), together with R837, promoted the activation, proliferation and recruitment of T cells. Besides, UTMD technology and DTX enhanced the accumulation of αPD-L1 in tumor sites. Moreover, RD@MBs remolded TIME, including the polarization of M2-phenotype tumor-associated macrophages (TAMs) to M1-phenotype, and reduction of myeloid-derived suppressor cells (MDSCs). The RD@MBs + αPD-L1 synergistic therapy not only effectively inhibited the growth of primary tumors, but also significantly inhibited the mimic distant tumors as well as lung metastases. Conclusion PD-L1 blockade immunotherapy was enhanced by RD@MBs delivery system

Development and Application of a High-Resolution Melting Analysis with Unlabeled Probes for the Screening of Short-Tailed Sheep TBXT Heterozygotes

The short-tailed phenotype has long been considered one of the best traits for population genetic improvement in sheep breeding. In short-tailed sheep, not only is tail fat eliminated but also the pubic area is exposed due to the lack of a tail covering, giving them an advantage in reproduction. Recent studies have shown that two linked mutations in sheep TBXT at nucleotides 333 and 334 are associated with the short-tailed phenotype. In the population of short-tailed sheep, several heterozygous mutants of this gene are found. In our research, we used high-resolution melting (HRM) to identify homozygous and heterozygous genotypes in a flock of short-tailed sheep and compared the results with those of Sanger sequencing, which were identical. This demonstrates that our established HRM method, a rapid and inexpensive genotyping method, can be used to identify homozygous and heterozygous individuals in short-tailed sheep flocks