Search

Abstract Insulin has been shown to modulate neuronal processes through insulin receptors. The ion channels located on neurons may be important targets for insulin/insulin receptor signaling. Both insulin receptors and acid-sensing ion channels (ASICs) are expressed in dorsal root ganglia (DRG) neurons. However, it is still unclear whether there is an interaction between them. Therefore, the purpose of this investigation was to determine the effects of insulin on the functional activity of ASICs. A 5 min application of insulin rapidly enhanced acid-evoked ASIC currents in rat DRG neurons in a concentration-dependent manner. Insulin shifted the concentration–response plot for ASIC currents upward, with an increase of 46.2 ± 7.6% in the maximal current response. The insulin-induced increase in ASIC currents was eliminated by the insulin receptor antagonist GSK1838705, the tyrosine kinase inhibitor lavendustin A, and the phosphatidylinositol-3 kinase antagonist wortmannin. Moreover, insulin increased the number of acid-triggered action potentials by activating insulin receptors. Finally, local administration of insulin exacerbated the spontaneous nociceptive behaviors induced by intraplantar acid injection and the mechanical hyperalgesia induced by intramuscular acid injections through peripheral insulin receptors. These results suggested that insulin/insulin receptor signaling enhanced the functional activity of ASICs via tyrosine kinase and phosphatidylinositol-3 kinase pathways. Our findings revealed that ASICs were targets in primary sensory neurons for insulin receptor signaling, which may underlie insulin modulation of pain.

Abstract Background The proliferation of porcine ovarian granulosa cells (GCs) is essential to follicular development and the ubiquitin–proteasome system is necessary for maintaining cell cycle homeostasis. Previous studies found that the deubiquitinase ubiquitin carboxyl-terminal hydrolase 1 (UCHL1) regulates female reproduction, especially in ovarian development. However, the mechanism by which UCHL1 regulates porcine GC proliferation remains unclear. Results UCHL1 overexpression promoted GC proliferation, and knockdown had the opposite effect. UCHL1 is directly bound to cyclin B1 (CCNB1), prolonging the half-life of CCNB1 and inhibiting its degradation, thereby promoting GC proliferation. What’s more, a flavonoid compound-isovitexin improved the enzyme activity of UCHL1 and promoted the proliferation of porcine GCs. Conclusions UCHL1 promoted the proliferation of porcine GCs by stabilizing CCNB1, and isovitexin enhanced the enzyme activity of UCHL1. These findings reveal the role of UCHL1 and the potential of isovitexin in regulating proliferation and provide insights into identifying molecular markers and nutrients that affect follicle development.

At present, wireless power transfer (WPT) systems with constant current (CC) or constant voltage (CV) characteristics are typically achieved using a single transmitter and single pickup (STSP) configuration, which cannot transfer power to multiple battery loads simultaneously. In this paper, the LCC-LCC/S reconfigurable topology is proposed to realize the CC-to-CV transition for multiple battery loads. An LCC topology is designed on the primary side to achieve a constant current (0.362A) flowing through the transmitting coil to enable independent operation of power pickups. A reconfigurable LCC/S topology is designed on the secondary side to achieve the CC-to-CV transition of the battery loads. The received power from the pickups remains unaffected when pickups are moved in or out or are in different operating modes (CC or CV). The circuit can maintain zero phase angle (ZPA) operation, which greatly enhances the overall power density of the system. Additionally, detailed design process for the compensation parameters on both the primary and secondary sides are provided. Theoretical analysis proves that good system stability and robustness can be obtained in the case of variable quantity of pickups and quality factors of coils. The experimental prototype was built, with the CC value for the battery load designed at 0.7A and the CV value designed at 8 V. Experimental results demonstrate the smooth CC-to-CV transition of the proposed WPT system (with 3 pickups) at a power output of 15.4 W, and the system’s maximum efficiency can reach 75.5 %.

Areal density gradient flyers (ADGFs) have important applications in quasi-isentropic compression and high strain rate loading. The wave impedance gradient distribution of the reported ADGFs is single, and the effects of different wave impedance gradient distributions and spikes number density on the loading results are unknown. In this study, the resin-based ADGFs with different spike areal density distribution and spikes number density were designed and prepared using projection micro stereolithography technology (PμSL). The printing accuracy of ADGFs was evaluated using three-dimensional optical profiler, optical microscope, Scanning Electron Microscopy (SEM) and ultra depth of field microscope. The loading process of the ADGF on the target was studied by experiment and simulation. The simulation result was consistent with the experimental result. Augmenting the wave impedance distribution index (P) of spikes and spikes number density increases the loading strain rate. Due to the high printing accuracy of PμSL, the fine ADGF structures with large spikes number density can be prepared, thereby promoting the formation of quasi-isentropic compression plane waves. This work realizes the regulation of loading strain rate under shockless quasi-isentropic compression, which is significant for understanding the mechanical response of materials under high strain rate loads.

Abstract Vibration with a frequency of 100 Hz is widely distributed in the power equipment, and it can provide a new way to supply energy for sensors by vibration energy harvesting. The vibration energy harvesting method based on electromagnetic induction principle was studied through the arrayed structure of magnets and coils. Static magnetic field models were established for four magnet array structures and it was found that the alternating magnet array has the largest magnetic flux and magnetic flux gradient. Based on the alternating magnet array, prototypes of energy harvester with vertical and parallel movement mode were proposed. Through structural parameter optimisation analysis, two different energy harvesters were fabricated and it was found that the energy harvester with a parallel movement mode has better output performances. The energy harvester could provide output voltage/current and power of 8.35 V/17.39 mA and 15.13 mW (matched resistance is 200 Ω) at an acceleration of 5 m·s−2. The 100 mF capacitor could be charged to 2.72 V within 300 s, and the final voltage of the capacitor is greater than 3 V, which could sustainably drive commercial wireless temperature/humidity sensors.

Ovarian follicle development is associated with the physiological functions of granulosa cells (GCs), including proliferation and apoptosis. The level of miR-24-3p in ovarian tissue of high-yielding Yorkshire×Landrace sows was significantly higher than that of low-yielding sows. However, the functions of miR-24-3p on GCs are unclear. In this study, using flow cytometry, 5-ethynyl-2´-de-oxyuridine (EdU) staining, and cell count, we showed that miR-24-3p promoted the proliferation of GCs increasing the proportion of cells in the S phase and upregulating the expression of cell cycle genes, moreover, miR-24-3p inhibited GC apoptosis. Mechanistically, on-line prediction, bioinformatics analysis, a luciferase reporter assay, RT-qPCR, and Western blot results showed that the target gene of miR-24-3p in proliferation and apoptosis is cyclin-dependent kinase inhibitor 1B (P27/CDKN1B). Furthermore, the effect of miR-24-3p on GC proliferation and apoptosis was attenuated by P27 overexpression. These findings suggest that miR-24-3p regulates the physiological functions of GCs.

Experimental studies were conducted on four extended end-plate joints subjected to cyclic loading at the column top, investigating the evolving patterns of the joints' mechanical performance. The paper provides a detailed analysis and discussion of the test joints' failure modes, ductility, stiffness degradation, and energy dissipation capacity. The Mann-Kendall (M − K) trend analysis tool was applied to the mechanical response curves, identifying key performance evolution points (evolution initiation point P and overall yield point Q). The trends in bolt forces, deformations, and strains at critical joints were effectively validated, revealing the transition of the energy system from quantitative to qualitative changes and the component's failure process from stability to instability. Additionally, based on the experimental joints' hysteresis curves and energy dissipation capacity, a theoretical hysteresis model was established to predict the joint's hysteresis curve and cumulative dissipated energy accurately. According to EC3 requirements, joints were classified as partially rigid connections. The experimental results of the initial rotational stiffness and plastic moment were further used to evaluate the calculated values in existing standards EN 1993-1-8, ANSI/AISC 358-16, and GB 51017-2017. The results indicate that extended end-plate connections possess sufficient strength, joint rotational stiffness, ductility, and energy dissipation capacity, making them suitable for seismic moment frames.

IntroductionAlthough there have been many researches on the etiology and risk factors with the onset of hemifacial spasm, researches on the risk factors related to progression rate are limited. This study aims to analyze the risk factors related to the progression rate of hemifacial spasm.MethodsThe study enrolled 142 patients who underwent microvascular decompression for hemifacial spasm. Based on the duration and severity of symptoms, patients were classified into rapid progression group and slow progression group. To analyze risk factors, univariate and multivariate logistic regression analyses were conducted. Of 142 patients with hemifacial spasm, 90(63.3%) were classified as rapid progression group, 52(36.7%) were classified as slow progression group.ResultsIn the univariate analysis, there were significant statistical differences between the two groups in terms of age of onset (P = 0.021), facial nerve angle (P < 0.01), hypertension (P = 0.01), presence of APOE ε4 expression (P < 0.01) and different degrees of brainstem compression in the Root Entry Zone (P < 0.01). In the multivariable analyses, there were significant statistical differences between the two groups in terms of age of symptom onset (P < 0.01 OR = 6.591), APOE ε4 (P < 0.01 OR = 5.691), brainstem compression (P = 0.006 OR = 5.620), and facial nerve angle (P < 0.01 OR = 5.758). Furthermore, we found no significant correlation between the severity of facial spasms and the progression rate of the disease (t = 2.47, P = 0.12>0.05).ConclusionAccording to our study, patients with facial nerve angle ≤ 96.5°, severer compression of the brainstem by offending vessels, an onset age > 45 years and positive expression of APOE ε4, may experience faster progression of hemifacial spasm.

Abstract Background Clock circadian regulator (CLOCK) is a core factor of the mammalian biological clock system in regulating female fertility and ovarian physiology. However, CLOCK's specific function and molecular mechanism in porcine granulosa cells (GCs) remain unclear. In this study, we focused on CLOCK’s effects on GC proliferation. Results CLOCK significantly inhibited cell proliferation in porcine GCs. CLOCK decreased the expression of cell cycle-related genes, including CCNB1, CCNE1, and CDK4 at the mRNA and protein levels. CDKN1A levels were upregulated by CLOCK. ASB9 is a newly-identified target of CLOCK that inhibits GC proliferation; CLOCK binds to the E-box element in the ASB9 promoter. Conclusions These findings suggest that CLOCK inhibits the proliferation of porcine ovarian GCs by increasing ASB9 level.

Abstract This paper proposes a novel cubic WPT system for an enclosed sensor scenario, and its transmission characteristics in a metal environment have been analyzed. In addition, stable and high transmission efficiency can be normally achieved in all positions. The proposed quasi‐double D coil structure is composed of two pairs of transmitting coils; each transmitting coil pair is placed face to face and connected serially. Through current amplitude modulation, magnetic flux can flow towards the centre of the receiving coil and keep the system high efficiency when the rotation angle of the receiving coil changes. However, the installation position of the receiving coil is not fixed in the switch cabinet application, and an irregular iron wall and the metal shell of sensors could also lead to inconsistent iron loss of multiple transmitters. To overcome the resulting disturbances in efficiency, the improved current amplitude control method and the optimal load have been theoretically deduced in the case of the position variation of the receiving coil in a metal environment. Finally, experimental results in two‐dimensional space verify the omnidirectional transmission capability of the proposed quasi‐double D coil, and efficiency disturbances are effectively alleviated.

Aiming at the problems of low efficiency, high labor intensity and single function of picking equipment at the current stage of manual apple picking, this study is based on the TRIZ and inspired by the principle of invention, to analyze the end effector, transport device, collection box and other structures of the apple picking robot. With innovative design, a robot integrating picking, collecting and sorting functions has been designed. The D-H model of the picking manipulator is established, the working space of the robot is analyzed by Matlab, the motion simulation of the picking process of the robot is carried out by Adams, and a 1∶3 experimental prototype is made to verify the functional feasibility of each part. The results show that the functions of each part of the robot are perfect, the design is reasonable, the operation is reliable, and it meets the needs of use, which provides theoretical support for the further development and improvement of the follow-up robot.

In Hilbert space, the geometry of the quantum state is identified by the quantum geometric tensor (QGT), whose imaginary part is the Berry curvature and whose real part is the quantum metric tensor. Here, we experimentally realize a complete Bloch-state tomography to directly measure the eigenfunction of an optical Raman lattice for ultracold atoms. Through the measured eigenfunction, the distribution of the complete QGT in the Brillouin zone is reconstructed, with which the topological invariants are extracted by the Berry curvature and the distances of quantum states in momentum space are measured by the quantum metric tensor. Furthermore, we experimentally test a predicted inequality between the Berry curvature and the quantum metric tensor, which reveals a deep connection between the topology and geometry.

Good impedance matching and attenuation ability of electromagnetic wave absorbing (EMA) materials are required to broaden the effective absorbing bandwidth (EAB) and reduce minimum reflection loss (RLmin), achieving high EMA performance. Here we report a polymethylmethacrylate (PMMA)-based composites foam with alternating and directional (AD) microporous structure that possessing broadened EAB value of 3.53 GHz (8.49–12.02 GHz) and lowered RLmin value of −19.35 dB, was manufactured via the one-step physical constraint foaming technology. Structural studies reveal that the AD microporous structure can induce the carbon nanotubes (CNTs) oriented distribution to improve effective concentration of CNTs, achieving excellent impedance matching. Meanwhile, a large number of parallel-plate capacitors at the multilayer layer interfaces were generated to promote interfacial polarization, including enhancement of multiple reflection and scattering of electromagnetic wave at the layer interfaces. Thereby, the composites foams exhibited high attenuation ability. This study lays the foundation for rational design and synthesis of EMA materials for wideband EMA performance.

Abstract Sulphur hexafluoride (SF6) is widely used in gas insulation, and its decomposition products can be used to diagnose potential insulation failures. Quick and accurate detection of decomposition products can help to understand equipment‐operating conditions in time. In this study, the decomposition products of SF6/air gas mixtures under different pulsed discharge voltages were studied. It was found that the main products were SOF2, SO2F2, SO2, CF4 and SOF4, and the yields of SOF2, SO2F2, SO2 and SOF4 increased with the number of discharge pulse. The productive rate of SOF2, SO2 and SOF4 were positively correlated with the discharge voltage, and when the discharge voltage increased from 5 to 15 kV, their yields after 50,000 discharges increased by 49%, 120% and 1100%, respectively. The productive rate of SOF2 and SO2 were positively correlated with the proportion of air in the gas mixtures while that of SOF4 was opposite. When the proportion of air increases from 0% to 90%, their yields after 50,000 discharges became 270%, 3169% and 10% of the originals, respectively. In addition, the productive rate of SO2F2 was not affected by discharge voltage and the proportion of air in the gas mixtures. SO2F2, SOF2, SOF4 and SO2 can be used as the basis for judging the discharge failures and the discharge degree of power equipment.

Bridges’ expansion joints are prone to damage during operation, and repairing them often requires interruption of traffic, the impact of which can be minimized by using fast-hardening and early-strength expansion joint materials. In this study, a fast-hardening polymer cement composite (PCC) was developed using sulfate aluminate cement and ordinary silicate cement as binding agents and polymer powder as admixture. To improve the crack resistance of the material, several types of fibers were added and the effects of different fiber types and admixtures on the crack resistance of the material were compared using SCB tests. The results showed that the best effect of improving the crack resistance of concrete was achieved with a volume fraction of 0.5% of basalt fibers. Then, a test method for the interfacial shear properties of PCC materials and ordinary concrete was established, and the cohesive force model was selected as the interface simulation parameter for finite element analysis and compared with experimental data to verify its feasibility. Finally, based on the previously obtained PCC material parameters, a solid model of the expansion joint anchorage zone was established to study the mechanical properties of the expansion joint anchorage zone with the application of fast-hardening PCC material. This research provides a new way to develop fast-hardening and early-strength expansion joint materials with high crack resistance.

Abstract Stray magnetic fields with a fixed frequency of 50/60 Hz are ubiquitous in buildings, factories, and power system equipment. Researchers are increasingly focusing on harvesting electrical energy from stray magnetic fields to provide sustainable energy for the Internet of Things (IoT) devices. Magneto‐mechano‐electric energy conversion is the most efficient way to convert low‐frequency stray magnetic fields into electricity. In this study, we proposed a hybrid piezo/triboelectric nanogenerator (HP/TENG) on the basis of a cantilever beam to use stray magnetic fields from the surrounding environment. The hybrid nanogenerator provided high output voltage/current and power of ∼176 V/375 μA and 4.7 mW (matched impedance of 20 kΩ) in a magnetic field environment of 4 Oe. The device provided a stable 3.6 V direct current output by incorporating energy management circuitry to sustainably drive power to commercial wireless temperature/humidity sensors. The HP/TENG has a significant application potential in IoT, which can use stray magnetic energy and a power wireless sensor system.

Abstract Background Despite the medical importance of mosquitoes of the genus Anopheles in the transmission of malaria and other human diseases, its phylogenetic relationships are not settled, and the characteristics of mitochondrial genome (mitogenome) are not thoroughly understood. Methods The present study sequenced and analyzed the complete mitogenomes of An. peditaeniatus and An. nitidus, investigated genome characteristics, and inferred the phylogenetic relationships of 76 Anopheles spp. Results The complete mitogenomes of An. peditaeniatus and An. nitidus are 15,416 and 15,418 bp long, respectively, and both include 13 PCGs, 22 tRNAs, two tRNAs and one control region (CR). Mitogenomes of Anopheles spp. are similar to those of other insects in general characteristics; however, the trnR and trnA have been reversed to “trnR-trnA,” as has been reported in other mosquito genera. Genome variations mainly occur in CR length (493–886 bp) with six repeat unit types identified for the first time that demonstrate an evolutionary signal. The subgenera Lophopodomyia, Stethomyia, Kerteszia, Nyssorhynchus, Anopheles and Cellia are inferred to be monophyletic, and the phylogenetic analyses support a new phylogenetic relationship among the six subgenera investigated, in that subgenus Lophopodomyia is the sister to all other five subgenera, and the remaining five subgenera are divided into two clades, one of which is a sister-taxon subgenera Stethomyia + Kerteszia, and the other consists of subgenus Nyssorhynchus as the sister to a sister-group subgenera Anopheles + Cellia. Four series (Neomyzomyia, Pyretophorus, Neocellia and Myzomyia) of the subgenus Cellia, and two series (Arribalzagia and Myzorhynchus) of the subgenus Anopheles were found to be monophyletic, whereas three sections (Myzorhynchella, Argyritarsis and Albimanus) and their subdivisions of the subgenus Nyssorhynchus were polyphyletic or paraphyletic. Conclusions The study comprehensively uncovered the characteristics of mitogenome and the phylogenetics based on mitogenomes in the genus Anopheles, and provided information for further study on the mitogenomes, phylogenetics and taxonomic revision of the genus. Graphical abstract

Abstract In this paper, we use the inverse design method to design an optical interconnection system composed of wavelength demultiplexer and the same direction waveguide crossing on silicon-on-insulator (SOI) platform. A 2.4 μm × 3.6 μm wavelength demultiplexer with an input wavelength of 1.3–1.6 μm is designed. When the target wavelength of the device is 1.4 μm, the insertion loss of the output port is − 0.93 dB, and there is − 18.4 dB crosstalk, in TE0 mode. The insertion loss of the target wavelength of 1.6 μm in TE0 mode is − 0.88 dB, and the crosstalk is − 19.1 dB. Then, we designed a same direction waveguide crossing, the footprint is only 2.4 μm × 3.6 μm, the insertion loss of the wavelength 1.4 μm and 1.6 μm in TE0 mode is − 0.99 dB and − 1 dB, and the crosstalk is − 12.14 dB and − 14.34 dB, respectively. Finally, an optical interconnect structure composed of two devices is used, which can become the most basic component of the optical interconnect network. In TE0 mode, the insertion loss of the output wavelength of 1.4 μm at the output port is − 1.3 dB, and the crosstalk is − 29.36 dB. The insertion loss of the output wavelength of 1.6 μm is − 1.39 dB, and the crosstalk is − 38.99 dB.

Abstract A difficult issue restricting the development of gas sensors is multicomponent recognition. Herein, a gas-sensing (GS) microchip loaded with three gas-sensitive materials was fabricated via a micromachining technique. Then, a portable gas detection system was built to collect the signals of the chip under various decomposition products of sulfur hexafluoride (SF6). Through a stacked denoising autoencoder (SDAE), a total of five high-level features could be extracted from the original signals. Combined with machine learning algorithms, the accurate classification of 47 simulants was realized, and 5-fold cross-validation proved the reliability. To investigate the generalization ability, 30 sets of examinations for testing unknown gases were performed. The results indicated that SDAE-based models exhibit better generalization performance than PCA-based models, regardless of the magnitude of noise. In addition, hypothesis testing was introduced to check the significant differences of various models, and the bagging-based back propagation neural network with SDAE exhibits superior performance at 95% confidence.

Compressive sensing (CS) is an effective technique that can compress and recover sparse signals below the Nyquist-Shannon sampling theorem restriction. In this study, we successfully realize CS based on the mesoscopic chaos of an integrated Si optomechanical photonic crystal micro-cavity, which is fully compatible with the complementary metal-oxide-semiconductor (CMOS) process. Using the sensing matrix, we tested one-dimensional waveforms and two-dimensional images. The ultimate recovery curves were determined by comparing the chaotic sensing matrix with the Gaussian, Toeplitz, and Bernoulli matrices. Our results could pave the way for future large-scale implementations of high-speed CS processes based on fully CMOS-compatible Si-micro-cavities.

Image online monitoring technology has been widely used in transmission lines inspection, but the intelligent and efficient foreign object detection still has a gap with the ideal. In this paper, we propose a deep learning method to detect invading foreign objects for power transmission line inspection. Specifically, we design our network based on the regression strategy with oriented bounding boxes to accurately predict spatial location and orientation angle of foreign objects, as well as their categories in cluttered backgrounds. Moreover, an easy yet effective Scale Histogram Matching method is proposed to be applied to the publicly available dataset, allowing useful patterns to be exploited to detect tiny foreign objects during the pretraining procedure and boosting detection performance even with limited annotated samples. Besides, we construct an image dataset that contains common foreign objects in transmission line scenarios to evaluate proposed methods, on which experiment results show our full model achieves accuracy with 88.1% mean Average Precision (mAP). Additionally, the efficient and compact network structure allows our network to run in real-time, which provides possibilities for practical use.

Mesenchymal stem cells (MSCs) participate in the occurrence and development of multiple myeloma. This study is aimed at exploring whether the presence of MSCs affects dexamethasone’s antitumor effects against multiple myeloma. Multiple myeloma cells (OPM-2 and RPMI8226 cells) were cocultured with MSCs with or without dexamethasone. Cell viability was determined by using cell number count, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and colony formation assay, respectively. Cell cycle distribution and cell apoptosis were evaluated by using flow cytometry. The mRNA and protein expressions of target genes were checked by using qRT-PCR and western blotting, respectively. It was found that cell viability of multiple myeloma cells increased in the presence of MSCs. Besides, the presence of MSCs suppressed cell apoptosis induced by dexamethasone via the regulation of BCL-2 (B cell lymphoma 2). The presence of MSCs also affected the effects of dexamethasone on cell cycle distribution. Similarly, LINC00461 overexpression suppressed the inhibition of cell proliferation, suppressed the induction of cell apoptosis, and affected the effects on cell cycle distribution induced by dexamethasone insult. However, LINC00461 knockdown enhanced the inhibitory effects on cell proliferation and the induction of cell apoptosis induced by dexamethasone. In summary, MSCs inhibited the effects of dexamethasone on multiple myeloma and its regulatory effects were associated with LINC00461.

In this study, we report the complete mitochondrial genomes (mtgenome) of Thyreus decorus, Ceratina okinawana and Amegilla calceifera, which are the first time of mtgenome report also for the genera Thyreus, Ceratina and Amegilla in the family Apidae. They contain 15,237, 15,207, and 17,728 bp, with AT content of 84.97%, 79.30%, and 84.63%, respectively. Each mtgenome includes 13 protein-coding genes (PCGs), 22 transfer RNA (tRNAs), two ribosomal RNA (16S and 12S rRNA) and an AT-rich control region (CR). The phylogenetic relationships of 45 species in the family were constructed using Bayesian Inference based on concatenated nucleotide sequences of 13 PCGs. Our study suggests that the subfamily Apinae is a paraphyletic group, with the genus Eucera claded into the subfamily Xylocopinae and the genera Amegilla and Thyreus into the subfamily Nomadinae. In Apinae, the genera Melipona and Bombus are significantly sister group, and the genus Apis is the sister group with Melipona + Bombus.

An ultra-compact multimode wavelength demultiplexer (MWD) with a footprint of 3.6 × 2.4 μm2 was designed. Its size is approximately two orders of magnitude smaller than the size of the traditional waveguide-based device. Moreover, the designed demultiplexer is multifunctional, and can realize wavelength demultiplexing and mode conversion at the same time. This MWD splits light at the wavelengths of 1450 nm and 1550 nm and simultaneously converts the input light from the fundamental transverse electric (TE0) mode to the first-order transverse electric (TE1) mode. The direct binary search (DBS) algorithm was employed to simulate the design. The results show that the insertion loss of the demultiplexer is −1.26 dB and −0.82 dB for the upper channel (wavelength 1450 nm) and lower channel (wavelength 1550 nm), while the crosstalk values are maintained as low as −18.10 dB and −23.35 dB, respectively. Additionally, a similar structure can be expanded to several modes. Based on these advantages, this multifunctional photonics device is expected to be used extensively in advanced photonic integration circuits.

In recent years, metasurfaces have demonstrated a tremendous development potential and applicability in various fields as they have overcome the problems associated with traditional optical devices, including bulkiness and difficulties related to integration. The vortex beam can carry an unlimited amount of orbital angular momentum which can greatly increase the capacity of the communication system and thus attain a tremendous applicability potential in communication and information transmission. In this study, a vortex-focused beam metalens array is designed based on computer-generated holography technology for use in the visible light range. The antenna’s unit structure is arranged according to the phase distribution designed using computer-generated holography technology. The metalens array can convert circularly polarized light into a vortex beam and can focus the vortex beam. At the wavelengths of 420 nm, 550 nm, and 660 nm, the average conversion efficiency exceeds 80%, and the phase distribution is in the range of 0–2π. The metalens array can simultaneously generate and focus the vortex beams. We also studied the focusing effect of different vortex beams, and we analyzed and compared the focal length and full width at half maximum of metalens at different wavelengths and different topological charges. In addition, the focusing of the primary color light by the 3 × 3 metalens array is simulated. The design presented in this study is envisaged to be applied extensively in the fields of optical photography and optical communication systems.

An optical switch based on silicon-on-insulator (SOI) technology is proposed that works in the C-band and switches by amorphous (Am) to crystalline (Cr) and Cr-to-Am phase transitions. The optical switch integrates the functions of polarization beam splitting and mode conversion, and consists of two asymmetric directional couplers (ADCs). The TM0 mode is converted to the TM1 mode through an asymmetric coupler to achieve the polarization splitting of the TM0 mode and TE0 mode. The output of the TE0 mode is then controlled by Ge2Sb2Se4Te1 (GSST). When the TE0 mode is input and the wavelength is 1550 nm, the insertion loss (IL) is lower than 0.62 dB and the crosstalk (CT) is lower than −9.88 dB for a directional coupler loaded with GSST that realizes the optical switch function in both amorphous and crystalline GSST. The extinction ratio (ER) of the two waveguides of the directional coupler is lower than −11.40 dB, simultaneously. When the TM0 mode is input and the wavelength is 1550 nm, the IL is lower than 0.62 dB for a directional coupler loaded without GSST.

Logic gates, as one of the most important basic units in electronic integrated circuits (EICs), are also equally important in photonic integrated circuits (PICs). In this study, we proposed a non-volatile, ultra-compact all-photonics logic gate. The footprint is only 2 μm × 2 μm. We regulate the phase change of optical phase change materials(O-PCMs) Sb2Se3 to switch the function of the logic gate. The Sb2Se3 possess a unique non-volatile optical phase change function; therefore, when Sb2Se3 is in the crystalline or amorphous state, our device can work as XOR gate or AND gate, and our designed logic ‘1’ and logic ‘0’ contrasts reach 11.8 dB and 5.7 dB at 1550 nm, respectively. Compared with other traditional optical logic gates, our device simultaneously has non-volatile characteristics, tunability, and additionally an ultra-small size. These results could fully meet the needs of fusion between PICs and EICs, and developing truly chip-scale optoelectronic logic solution.

Metal oxide semiconductors (MOSs) are widely used gas-sensing materials because of their large response values and fast response speed. However, high operating temperature hinders the development of MOS-based gas sensors. To detect SF6 decomposition components (including H2S, SO2, SOF2, and SO2F2), here, we have synthesized cerium oxide nanoparticles (CeO2 NPs) via a facile hydrothermal routine, followed by functionalization with Au, Ag, and Pd noble metals to improve sensor performance. Our developed CeO2-based sensor exhibited high response to target gases at a low working temperature. After doping various metals into the CeO2 NPs, we acquired distinct patterns of dynamic responses for SF6 decomposition components. Au functionalization could maximize the enhancements of sensor responses to H2S (976%), SO2 (153%), and SOF2 (151%) at 100 °C, and a Pd-modified CeO2-based sensor exhibited optimal response to SO2F2 at a relatively high temperature of 250 °C. In addition, high response values, short response–recovery times, good repeatability, and low detection limits were also obtained from CeO2-based sensors. Our results verified that doping different noble metals into CeO2 NPs should be a promising strategy to design high-performance gas sensors for SF6 decomposition component detection. Keywords: Gas sensor, CeO2, Noble metal functionalization, SF6 decomposition components

A series of reconfigurable compact photonic arbitrary power splitters are proposed based on the hybrid structure of silicon and Ge2Sb2Se4Te1 (GSST), which is a new kind of non-volatile optical phase change material (O-PCM) with low absorption. Our pixelated meta-hybrid has an extremely small photonic integrated circuit (PIC) footprint with a size comparable to that of the most advanced electronic integrated circuits (EICs). The power-split ratio can be reconfigured in a completely digital manner through the amorphous and crystalline switching of the GSST material, which only coated less than one-fifth of the pattern allocation area. The target power–split ratio between the output channels can be arbitrarily reconfigured digitally with high precision and in the valuable C-band (1530–1560 nm) based on the analysis of three-dimensional finite-difference time-domain. The 1 × 2, 1 × 3, and 1 × 4 splitting configurations were all investigated with a variety of power–split ratios for each case, and the corresponding true value tables of GSST distribution are given. These non-volatile hybrid photonic splitters offer the advantages of an extremely small footprint and non-volatile digital programmability, which are favorable to the truly optoelectronic fusion chip.

A noticeable challenge for a multi-load wireless power transfer system is to achieve stable power transfer under a dynamic change in coupling conditions. It was proposed that the parity–time symmetric wireless power transfer (PT-WPT) system can achieve stable output efficiency for a single receiver when tuned at the purely real eigenfrequency. However, in the case of higher order, PT symmetric systems usually cannot maintain the real eigenfrequency. To address the issue, a high-order PT-WPT model was established using coupled mode theory (CMT) theory in this paper, and the eigenfrequency of the multi-load PT-WPT system was analyzed. Here, we propose that, theoretically, the system can work at the purely real eigenfrequency by impedance matching. The transfer efficiency of the multi-load PT-WPT system when the system works at the real eigenfrequency was analyzed. The results of the numerical simulation show that the multi load PT-WPT system can maintain stable output efficiency under a dynamic change in coupling conditions. In the long run, our work provides a new possibility for the stable transmission of the multi-load wireless power transfer system.

In order to study the conductive and microwave absorption performance of multi-dimensional multiphase filler conductive foam composites, carbon nanotubes (CNTs)/carbon black (CB)/polymethyl methacrylate (PMMA) nanocomposites with different porosity were fabricated via supercritical carbon dioxide (ScCO _2 ) one-step physical constraint foaming technology. The effects of filler component and porosity on the conductivity and absorbing properties of CNTs/PMMA/CB composite foam were studied. The Monte-Carlo method was used to study the percolation of composites and the effect of introduced microcells on the conductive network of multi-dimensional fillers. The results revealed that the volume conductivity of CNTs(3 vol%)/PMMA composites increased from 0.88 S m ^−1 to 3.31 S m ^−1 after the addition of 1 vol% CB. CNTs and CB had obvious synergistic effect on improving the conductivity of the composites, and the microwave absorption efficiency rose from 12.6 dB to 17.2 dB. With the increase of porosity, the electromagnetic wave absorption peak of CNTs/CB/PMMA composite foam moved to low frequency, while the conductivity showed a first rise and then a decline. The simulated percolation probability obtained by representative volume element (RVE) with different porosity also showed a similar trend, which turned out that with the increase of porosity, the effect of microcells on the convertion of conductive network construction from promoting to inhibiting.

The construction of heterostructured photocatalyst with an appropriate energy band structure will help realize highly efficient photo-excited charge separation. In this study, ternary CuO/CeO2/ZnO nano-particle (NP) composites were synthesized by a facile two-step sol-gel method, which exhibit significantly enhanced photocatalytic degradation performance for various organic pollutants under UV and visible light excitation. The photo-responses to both UV and visible light, as well as the visible light absorption and utilization rates of ZnO are found to be synergistically intensified by CeO2 and CuO co-coupling. The first-order kinetic constants (K) of 3%CuO/CeO2/ZnO for methylene blue (MB) degradation are ~3.9, ~4.1 and ~4.8 times higher than ZnO under UV light, visible light and simulated sunlight illumination, respectively. The roles of CuO and CeO2 in optical properties and photo-degradation under UV and visible light were explored. Besides, the photogenic holes (h+) of ZnO, CeO2, and the produced hydroxyl radicals (·OH) are proved to be the main active species under UV light. Dissimilarly, under visible light, the superoxide radicals (·O2−) formed by the reactions between oxygen molecules and the photo-generated electrons (e−) of CuO moving towards the catalysts surface are also found to be important for promoting dye decomposition. The improved photo-responses, the well-matched band structure that facilitates charge transfer processes, and the highly efficient utilization of the photo-excited carriers of the ternary nano-heterostructure are suggested to be the key factors for the remarkable enhancement of photocatalytic performance of ZnO nano-photocatalyst. This work offers a low-cost strategy to acquire highly active UV and visible light-driven photocatalyst.

Recent studies have found that administration of stem cells or extracellular vehicles (EVs) derived from stem cells exert neuroprotective effects after transient global ischemia. However, the underlying mechanisms of this effect remain unclear, especially at the level of synaptic functions. In this study, we compared the suppressive effects on cyclooxygenase-2 (COX-2) upregulation by EVs derived from bone marrow mesenchymal stem cells (BMSC-EV), adipose tissue MSC (AdMSC-EV) and serum (serum-EV). Then we examined whether BMSC-EVs could restore functional integrity of synaptic transmission and plasticity. Mice were randomly assigned to four groups: sham, sham with EV treatment, ischemia and ischemia with EV treatment. EVs were administered by intracerebroventricular injection (ICVI). We examined the consequence of transient global ischemia on pre- and post-synaptic functions of the hippocampal CA3-CA1 synapses at basal level, and long-term potentiation (LTP), an activity-dependent form of synaptic plasticity. Then we tested the therapeutic effects of EVs on these synaptic deficits. Meanwhile, Morris water maze (MWM) test was performed to examine the efficacy of EVs in rescuing ischemia-induced impairments in spatial learning and memory. EV treatment significantly restored impaired basal synaptic transmission and synaptic plasticity, and improved spatial learning and memory compared with the control group. In addition, EVs significantly inhibited ischemia-induced pathogenic expression of COX-2 in the hippocampus. EVs exert ameliorating effects on synaptic functions against transient global cerebral ischemia, which may be partly attributed to suppression of COX-2 pathogenic expression.

ZnO nanoparticles (NPs) are synthesized by deoxidizing ZnO powder in a vacuum drying process. This process reduces the size of the NPs and increases the concentration of oxygen vacancies on their surfaces. ZnO NPs with sufficient oxygen vacancies are highly effective for the photodecomposition of methylene blue (MB) dye in water under ultraviolet irradiation. The MB degradation efficiency exceeds 99 percent after 50 min of light irradiation, and the catalytic property of the NPs remains stable over several complete degradation cycles. It is revealed that the concentration of oxygen vacancies on the surface, and the photocatalytic activity, are both higher for smaller NPs. Oxygen vacancies reduce the recombination rate of photo-generated charge carriers by capturing the electrons and hence, improve the efficiency of redox reactions. In addition, a smaller particle size leads to a larger specific surface area and a higher photonic efficiency for the ZnO NPs.