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Actin- and microtubule (MT)-based transport systems are essential for intracellular transport. During influenza A virus (IAV) infection, MTs provide long tracks for virus trafficking toward the nucleus. However, the role of the actin cytoskeleton in IAV entry and especially the transit process is still ambiguous. Here, by using quantum dot-based single-virus tracking, it was revealed that the actin cytoskeleton was crucial for the virus entry via clathrin-mediated endocytosis (CME). After entry via CME, the virus reached MTs through three different pathways: the virus (1) was driven by myosin VI to move along actin filaments to reach MTs (AF); (2) was propelled by actin tails assembled by an Arp2/3-dependent mechanism to reach MTs (AT); and (3) directly reached MTs without experiencing actin-related movement (NA). Therefore, the NA pathway was the main one and the fastest for the virus to reach MTs. The AT pathway was activated only when plenty of viruses entered the cell. The viruses transported by the AF and AT pathways shared similar moving velocities, durations, and displacements. This study comprehensively visualized the role of the actin cytoskeleton in IAV entry and transport, revealing different pathways for IAV to reach MTs after entry. The results are of great significance for globally understanding IAV infection and the cellular endocytic transport pathway.

Membrane tension is an important physical parameter of describing cellular homeostasis, and it is widely used in the study of cellular processes involving membrane deformation and reorganization, such as cell migration, cell spreading, and cell division. Despite the importance of membrane tension, direct measurement remains difficult. In this work, we developed a ratiometric fluorescent probe sensitive to membrane tension by adjusting the carbon chain structure based on polarity-sensitive fluorophores. The probe is sensitive to changes in membrane tension after cells were subjected to physical or chemical stimuli, such as osmotic shock, lipid peroxidation, and mechanical stress. When the polarity of the plasma membrane increases (the green/red ratio decreases) and the membrane tension increases, the relative magnitude of the membrane tension can be quantitatively calculated by fluorescence ratio imaging. Thus, the probe proved to be an efficient and sensitive membrane tension probe.

Epithelial ovarian cancer is among the deadliest gynecological tumors worldwide. Clinical treatment usually consists of surgery and adjuvant chemo- and radiotherapies. Due to the high rate of recurrence and rapid development of drug resistance, the current focus of research is on finding effective natural products with minimal toxic side effects for treating epithelial ovarian tumors. Cannabidiol is among the most abundant cannabinoids and has a non-psychoactive effect compared to tetrahydrocannabinol, which is a key advantage for clinical application. Studies have shown that cannabidiol has antiproliferative, pro-apoptotic, cytotoxic, antiangiogenic, anti-inflammatory, and immunomodulatory properties. However, its therapeutic value for epithelial ovarian tumors remains unclear. This study aims to investigate the effects of cannabidiol on epithelial ovarian tumors and to elucidate the underlying mechanisms. The results showed that cannabidiol has a significant inhibitory effect on epithelial ovarian tumors. In vivoexperiments demonstrated that cannabidiol could inhibit tumor growth by modulating the intestinal microbiome and increasing the abundance of beneficial bacteria. Western blot assays showed that cannabidiol bound to EGFR/AKT/MMPs proteins and suppressed EGFR/AKT/MMPs expression in a dose-dependent manner. Network pharmacology and molecular docking results suggested that cannabidiol could affect the EGFR/AKT/MMPs signaling pathway.

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacteriumspecies contains a novel β-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR–Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9–PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and ‘growth evolutionary’ trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs—such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.

Electrochemiluminescence (ECL) imaging, a rapidly evolving technology, has attracted significant attention in the field of cellular imaging. However, its primary limitation lies in its inability to analyze the motion behaviors of individual particles in live cellular environments. In this study, we leveraged the exceptional ECL properties of quantum dots (QDs) and the excellent electrochemical properties of carbon dots (CDs) to develop a high-brightness ECL nanoprobe (CDs-QDs) for real-time ECL imaging between living cells. This nanoprobe has excellent signal-to-noise ratio imaging capabilities for the single-particle tracking (SPT) of biomolecules. Our finding elucidated the enhanced ECL mechanism of CDs-QDs in the presence of reactive oxygen species through photoluminescence, electrochemistry, and ECL techniques. We further tracked the movement of single particles on membrane nanotubes between live cells and confirmed that the ECL-based SPT technique using CD-QD nanoparticles is an effective approach for monitoring the transport behaviors of biomolecules on membrane nanotubes between live cells. This opens a promising avenue for the advancement of ECL-based single-particle detection and the dynamic quantitative imaging of biomolecules.

Imparting procedural skills is challenging. Peyton’s approach is an effective face-to-face teaching technique increasingly used in complex skills training. Institutions are beginning to incorporate online training as part of their procedural curriculum. We developed E-Peyton’s to employ Peyton’s approach through an electronic learning platform. The efficacy of E-Peyton’s approach in teaching the interpretation of facial computed tomography (CT) scans is evaluated in this study. Naïve learners (n=41) were randomized into 2 groups based on teaching techniques employed: E-Peyton’s (n=20) and Peyton’s (n=21) approaches. The distance between the infraorbital margin and the posterior ledge was measured using a 3-part standardized measuring protocol on OsiriX. Twenty measurements were assessed for accuracy against the benchmark (±2 mm) at week 0 and week 1. Training durations were compared. Questionnaires were administered before and after the study to identify learners’ acceptance of teaching techniques and their confidence in interpreting facial CT scans. Learners in both teaching techniques had comparable skills retention. Gap scores indicate significant improvement in learner’s confidence levels regardless of teaching technique (P<0.05). Both teaching techniques were well-accepted by learners. E-Peyton’s and Peyton’s approaches required a similar training duration. The COVID-19 pandemic highlights the importance of effective remote learning platforms. E-Peyton’s approach is comparable to that of Peyton’s in all areas of assessment. E-Peyton’s approach effectively automates Peyton’s approach, allowing for standardized, high-quality procedural skills training while reducing manpower burden.

The employment of flexible piezoresistive sensors has sparked growing interest within the realm of wearable electronic devices, specifically in the fields of health detection and e-skin. Nevertheless, the advancement of piezoresistive sensors has been impeded by their limited sensitivity and restricted operating ranges. Consequently, it is imperative to fabricate sensors with heightened sensitivity and expanded operating ranges through the utilization of the appropriate methodologies. In this paper, piezoresistive sensors were fabricated utilizing electrospun polyvinylidene fluoride/polyacrylonitrile/polyethylene-polypropylene glycol multilayer fibrous membranes anchored with polypyrrole granules as the sensing layer, while electrospun thermoplastic polyurethane (TPU) fibers were employed as the flexible substrate. The sensitivity of the sensor is investigated by varying the fiber diameter of the sensing layer. The experimental findings reveal that a concentration of 14 wt % in the spinning solution exhibits high sensitivity (996.7 kPa–1) within a wide working range (0–10 kPa). This is attributed to the favorable diameter of the fibers prepared at this concentration, which facilitates the uniform in situ growth of pyrrole. The highly deformable TPU flexible fibers and multilayer sensing layer structure enable different linear responses across a broad pressure range (0–1 MPa). Furthermore, the sensor demonstrates good cyclic stability and can detect human movements under different pressures. These results suggest that the piezoresistive sensor with a wide operating range and high sensitivity has significant potential for future health monitoring and artificial intelligence applications.

Intermediate and ideal levels of cardiovascular health (CVH) metrics are associated with a markedly reduced risk of developing incident arrhythmias, including atrial fibrillation/flutter, ventricular arrhythmias, and bradyarrhythmia, independent of coronary heart disease.A majority of incident arrhythmias could be prevented if the risk profile of the entire population was optimized.These findings emphasize the significance of public health policies that improve CVH to reduce the social and economic burden of arrhythmias.

In recent years, the application of both fluorescence and photothermal systems in one system has received great attention in the biomedical field. Yet, synthesizing a nanomaterial with both fluorescence (radiative decay) and a photothermal effect (nonradiative decay) is rarely reported. Here, we proposed novel plasmonic-fluorescent Janus Au-PbS nanoparticles (NPs) with tunable near-infrared II (NIR-II) fluorescence and photothermal effect to be used as a highly effective nanotheranostic for dual-modal NIR-IIb fluorescence imaging (FI)/computed tomography imaging (CT)-guided photothermal therapy. In addition, we investigated the equilibrium mechanism between the fluorescence and photothermal effects to guide the synthesis of this type of nanomaterial and found that the fluorescent semiconductor PbS quantum dots (QDs) receive electrons from Au NPs in Janus Au-PbS NPs, which could maintain the good fluorescence properties of Janus Au-PbS NPs. In addition, the alteration of electron and hole recombination between PbS QDs and Au NPs in Janus Au-PbS NPs increased nonradiative decay, leading to enhanced photothermal effects of Janus Au-PbS NPs. The electron receiver and electron–hole interactions in Janus Au-PbS NPs offered a fundamentally new means of engineering materials with fluorescence and photothermal properties through tailoring electron redistribution in Janus NPs.

Labeling the genome and envelope of a virus with multicolor quantum dots (QDs) simultaneously enables real-time monitoring of viral uncoating and genome release, contributing to our understanding of virus infection mechanisms. However, current labeling techniques require genetic modification, which alters the virus’s composition and infectivity. To address this, we utilized the CRISPR/Cas13 system and a bioorthogonal metabolic method to label the Japanese encephalitis virus (JEV) genome and envelopes with different-colored QDs in situ. This technique allows one-step two-color labeling of the viral envelope and intraviral genome with QDs harnessing virus infection. In combination with single-virus tracking, we visualized JEV uncoating and genome release in real time near the endoplasmic reticulum of live cells. This labeling strategy allows for real-time visualization of uncoating and genome release at the single-virus level, and it is expected to advance the study of other viral infection mechanisms.

Exosomes play an important role in the spread of viral infections and immune escape. However, the exact ability and mechanisms by which exosomes produced during viral infections (vExos) infect host cells are still not fully understood. In this study, we developed a dual-color exosome labeling strategy that simultaneously labels the external and internal structures of exosomes with quantum dots to enable in situ monitoring of the transport process of vExos in live cells using the single-particle tracking technique. Our finding revealed that vExos contains the complete influenza A virus (IAV) genome and viral ribonucleoprotein complexes (vRNPs) proteins but lacks viral envelope proteins. Notably, these vExos have the ability to infect cells and produce progeny viruses. We also found that vExos are transported in three stages, slow–fast–slow, and move to the perinuclear region via microfilaments and microtubules. About 30% of internalized vExos shed the external membrane and release the internal vRNPs into the cytoplasm by fusion with endolysosomes. This study suggested that vExos plays a supporting role in IAV infection by assisting with IAV propagation in a virus-independent manner. It emphasizes the need to consider the infectious potential of vExos and draws attention to the potential risk of exosomes produced by viral infections.

The rejuvenation behavior of a Zr55Cu30Ni5Al10(at.%) metallic glass upon deep cryogenic cycling treatment was investigated. The sample was rejuvenated to a larger extent with increasing cyclic number, resulting in a higher enthalpy of relaxation and a lower density. The rejuvenation seems to be saturated after 200 cycles, which may originate from the limited content of free volume in the amorphous structure. The sample subjected to a higher cyclic number showed a lower hardness and better plasticity due to a larger shear transformation zone (STZ) volume. In this case, a lower shear plane formation energy facilitates the generation of multiple shear bands. Furthermore, it is found that the content of free volume has linear relationship with the plastic strain and the STZ volume. The results from molecular dynamics simulation also demonstrates that the atomic volume saturates with a higher degree of rejuvenation at a higher cooling rate of the simulated sample.

Polarization reconfigurable antennas are useful in certain wireless systems to adapt to different incident polarizations or measurement systems. In this work, we develop an innovative and simple frequency-controlled polarization-rotating antenna. The antenna provides continuous adjustment of the orientation of linear polarization (LP) over a range of 180°, making it suitable for applications such as identifying objects with diverse orientations in sensing and detection systems. We introduce a general model of an LP antenna, in which the orientation of polarization can be controlled with an adjustable phase shift. By substituting the phase shift in the model with one that is frequency dependent, a 180° LP rotation can be attained by sweeping the source frequency across a custom-designed bandwidth. This allows the implementation of an antenna system that can continuously adjust the orientation of LP in response to frequency scanning over a wide operating bandwidth. As demonstrated in a prototype, a 180° polarization scan with a realized gain varying between 7.0 and 9.8 dBi is achieved by sweeping the frequency from 9.6 to 11.65 GHz. The continuously frequency-scanning polarization rotation behavior offers a novel and efficient solution for polarization reconfiguration.

Solar-blind ultraviolet (UV) photodetectors (PDs) with high sensitivity and rapid photoresponse time are indispensable for practical applications in medical imaging diagnostics, military surveillance, advanced manufacturing, and other fields. This study presents a high-performance self-powered solar-blind UV PD, which is based on a gallium oxide (Ga2O3) microwire (MW)/gallium nitride (GaN) p-n heterojunction, with a single-layer graphene employed as the top electrode. The device showcases excellent rectification and photovoltaic characteristics, with an open-circuit voltage of 1.95 V, establishing it as a remarkable self-powered detector. When illuminated by a 265-nm light at 0-V bias, the device demonstrates a responsivity of 108.7 mA/W, a specific detectivity of ${4.2} \times {10}^{{12}}$ Jones, and an external quantum efficiency of 51.0%. Remarkably, the device exhibits an extremely fast response speed, with the rise/recovery times of 88.2/ $85~\mu $ s, and the response bandwidth is estimated to be 3.5 kHz. Furthermore, our exploration of utilizing the detector as an optical data receiver in optical communications enabled to produce promising results, indicating its forward-looking applications for solar-blind UV detection. This study offers a simple and practical method for developing high-performance self-powered solar-blind UV PDs using low-dimensional Ga2O3 single crystal, providing valuable insights for advancing research in optoelectronic devices that function without external power sources.

Objective: To uncover the mechanisms underlying the development of colorectal cancer (CRC), we applied bioinformatic analyses to identify key genes and experimentally validated their possible roles in CRC onset and progression. Methods: We performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis on differentially expressed genes (DEGs), constructed a protein-protein interaction (PPI) network to find the top 10 hub genes, and analyzed their expression in colon adenocarcinoma (COAD) and rectum adenocarcinoma (READ). We also studied the correlation between these genes and immune cell infiltration and prognosis and validated the expression of SLC9A2in CRC tissues and cell lines using qRT-PCR and Western blotting. Functional experiments were conducted in vitro to investigate the effects of SLC9A2on tumor growth and metastasis. Results: We found 130 DEGs, with 45 up-regulated and 85 down-regulated in CRC. GO analysis indicated that these DEGs were primarily enriched in functions related to the regulation of cellular pH, zymogen granules, and transmembrane transporter activity. KEGG pathway analysis revealed that the DEGs played pivotal roles in pancreatic secretion, rheumatoid arthritis, and the IL-17 signaling pathway. We identified 10 hub genes: CXCL1, SLC26A3, CXCL2, MMP7, MMP1, SLC9A2, SLC4A4, CLCA1, CLCA4, and ZG16.GO enrichment analysis showed that these hub genes were predominantly involved in the positive regulation of transcription. Gene expression analysis revealed that CXCL1, CXCL2, MMP1, and MMP7were highly expressed in CRC, whereas CLCA1, CLCA4, SLC4A4, SLC9A2, SLC26A3, and ZG16were expressed at lower levels. Survival analysis revealed that 5 key genes were significantly associated with the prognosis of CRC. Both mRNA and protein expression levels of SLC9A2were markedly reduced in CRC tissues and cell lines. Importantly, SLC9A2overexpression in SW480 cells led to a notable inhibition of cell proliferation, migration, and invasion. Western blotting analysis revealed that the expression levels of phosphorylated ERK (p-ERK) and phosphorylated JNK (p-JNK) proteins were significantly increased, whereas there were no significant changes in the expression levels of ERK and JNK following SLC9A2overexpression. Correlation analysis indicated a potential link between SLC9A2expression and the MAPK signaling pathway. Conclusion: Our study suggests that SLC9A2acts as a tumor suppressor through the MAPK pathway and could be a potential target for CRC diagnosis and therapy.

Stable imaging in adverse environments (e.g., total darkness) makes thermal infrared (TIR) cameras a prevalent option for night scene perception. However, the low contrast and lack of chromaticity of TIR images are detrimental to human interpretation and subsequent deployment of RGB-based vision algorithms. Therefore, it makes sense to colorize the nighttime TIR images by translating them into the corresponding daytime color images (NTIR2DC). Despite the impressive progress made in the NTIR2DC task, how to improve the translation performance of small object classes is under-explored. To address this problem, we propose a generative adversarial network incorporating feedback-based object appearance learning (FoalGAN). Specifically, an occlusion-aware mixup module and corresponding appearance consistency loss are proposed to reduce the context dependence of object translation. As a representative example of small objects in nighttime street scenes, we illustrate how to enhance the realism of traffic light by designing a traffic light appearance loss. To further improve the appearance learning of small objects, we devise a dual feedback learning strategy to selectively adjust the learning frequency of different samples. In addition, we provide pixel-level annotation for a subset of the Brno dataset, which can facilitate the research of NTIR image understanding under multiple weather conditions. Extensive experiments illustrate that the proposed FoalGAN is not only effective for appearance learning of small objects, but also outperforms other image translation methods in terms of semantic preservation and edge consistency for the NTIR2DC task. Compared with the state-of-the-art NTIR2DC approach, FoalGAN achieves at least 5.4% improvement in semantic consistency and at least 2% lead in edge consistency.

This letter proposes a novel technique to produce desired circularly polarized (CP) pencil beams at entire working frequency band for ultrawideband (UWB) planar array while suppressing grating lobes in pencil beams at high-frequency band. The approach is based on a ${\text {2}}\times {\text {2}}$ irregular sequential rotated subarray (ISRS) configuration, using UWB linearly polarized elements. The synthesis procedure involves optimizing initial element rotation angle of each ISRS, while ensuring that the rotation interval of $\pi /2$ is still maintained between neighboring elements of each subarray. The phase term applied to the array elements is determined by the contribution of the phase associated with rotation. The proposed technique suppresses grating lobes in the obtained patterns at high-frequency band more effectively than the sequential rotation technique (SRT) while maintaining a simple sequential phase feeding network compared with the random SRT. Finally, one typical case of synthesizing pencil beam with a planar rotated Vivaldi array is presented to confirm the benefits of the proposed technique.

A wideband conformal array antenna utilizing dual-polarized transmission and reflection elements is proposed. The proposed transmission and reflection element employs four-layer metal structures to obtain a larger phase coverage. To improve the bandwidth, the period is set to 0.3λ0 to smooth the phase response. The −2.0 dB bandwidths of the transmission and reflection elements are 77.0% and 190.0%, respectively. Furthermore, an all-metal monopole antenna is designed as a feed structure, which utilizes two orthogonal metal cylinders to enhance the bandwidth. For high gain, the conformal array antenna is assembled in a decagonal arrangement employing five transmission panels and five reflection panels, where each panel consists of 6 × 24 elements. Then, a transmission-reflection hybrid phase compensation method is used to collimate a far-field beam. The beam-scanning range of 360° is achieved by mechanically rotating the relative location of the ten panels. The measured results show that the prototype has a peak gain of 19.0 dBi. The −10 dB bandwidth and 3 dB gain bandwidth are 102.0% and 20.0%, respectively. This antenna is an attractive candidate for communication systems that require a conformal structure.

The effect of notch volume on the mechanical behavior of a novel high-strength and high-toughness steel with negative Poisson’s ratio effect (called NPR steel) was studied. First, the quasi-static tensile test of NPR steel with different notch volumes was carried out, and its failure characteristics and mechanical properties parameters were studied. Then, the modified Johnson-Cook (J-C) constitutive model with coupled notch volume ratio was proposed. The model was validated based on three-dimensional finite element numerical simulations. The results show that the engineering stress–strain curve of NPR steel has no yield platform, and has the mechanical properties of high strength, high elongation, and high energy absorption. Notch volume significantly affects the mechanical properties of NPR steel. The elongation, yield strength, tensile strength, and energy absorption characteristics of steel bar gradually decrease with the increase in notch volume. The notch volume ratio V∗, a characteristic parameter describing the notch volume of reinforcement, is defined, and the quantitative relationship between this parameter and mechanical parameters is established, which can accurately characterize the mechanical properties of specimens with different notch volume ratios. Based on the true stress–strain curves with different notch volume ratios, a constitutive model with modified Johnson-Cook model parameters is proposed. The finite element results show that the modified J-C model can accurately fit the quasi-static tensile mechanical behavior of NPR steel.

Translation is one of the many critical cellular activities regulated by viruses following host-cell invasion, and studies of viral mRNA translation kinetics and subcellular localization require techniques for the dynamic, real-time visualization of translation. However, conventional tools for imaging mRNA translation often require coding region modifications that may affect native translation. Here, we achieve dynamic imaging of translation with a tool that labels target mRNAs with unmodified coding regions using a CRISPR/dCas13 system with specific complementary paired guide RNAs. This system enables a real-time dynamic visualization of the translation process and is a promising tool for further investigations of the mechanisms of translation.

Leaky wave antennas (LWAs) have been widely investigated for wireless systems because of their simple feed, low profile, and easy integration. They typically have a dispersive traveling wave leading to beam squinting behavior, which can significantly decrease the useful operating bandwidth in point-to-point communications. An innovative method that avoids beam squint with frequency over a wide band is developed in this work using a negative dispersion slope. By integrating a baffle of square bracket-shaped metal pieces into a transverse-slot LWA, the main beam angle is almost fixed at an angle, $\theta = 37^{\circ } \pm 2^{\circ }$ , across a wide frequency band from 9.5 to 12.2 GHz. The wide bandwidth is a consequence of the negative dispersion slope produced by the interaction between the baffle and the slotted waveguide. In the $\theta = 37^{\circ }$ direction, the gain variation is less than 3 dB across this band. Equivalent circuit analysis and full-wave modeling are presented to demonstrate the negative-slope dispersion diagram. The obtained 3-dB gain curve exhibits a filter characteristic. In addition, the bandwidth can be chosen by a suitable selection of parameters. It is the first time that these desirable features have been reported for wideband fixed-beam LWAs. The final antenna was fabricated with a low-cost additive manufacturing (3-D printing) technology. The measured results agree well with the simulated ones and verify the effectiveness of the antennas developed in this way.

Recent researches have shown that metallic glasses (MGs) can be rejuvenated to a more metastable energy state by thermal or mechanical approaches, which causes a looser atomic packing. This process can effectively improve the overall plasticity of MGs. The present work started with the concept of ageing and rejuvenation of MGs, briefly introducing the probable methods to rejuvenate the MGs, then the advantages and disadvantages of various methods were summarized, and the effects of deep cryogenic cycling method (a non-destructive method to sample morphology and feasible to conduct) were investigated in detail. The effects of treating parameters on the degree of rejuvenation and the effects of rejuvenation on the mechanical and magnetic properties of MGs were also summarized. Finally, some conclusions in this field are drawn and some important questions that deserve further study are put forward.

The ultrasonic melt treatment (UMT) is widely used in the fields of casting and metallurgy. However, there are certain drawbacks associated with the conventional process of single-source ultrasonic (SSU) treatment, such as the fast attenuation of energy and limited range of effectiveness. In this study, the propagation models of SSU and four-source ultrasonic (FSU) in Al melt were respectively established, and the distribution patterns of acoustic and streaming field during the ultrasonic treatment process were investigated by numerical simulation and physical experiments. The simulated results show that the effective cavitation zone is mainly located in a small spherical region surrounding the end of ultrasonic horn during the SSU treatment process. When the FSU is applied, the effective cavitation zone is obviously expanded in the melt. It increases at first and then decreases with increasing the vibration-source spacing (Lv) from 30 mm to 100 mm. Especially, when the Lvis 80 mm, the area of effective cavitation zone reaches the largest, indicating the best effect of cavitation. Moreover, the acoustic streaming level and flow pattern in the melt also change with the increase of Lv. When the Lvis 80 mm, both the average flow rate and maximum flow rate of the melt reach the highest, and the flow structure is more stable and uniform, with the typical morphological characteristics of angular vortex, thus significantly expanding the range of acoustic streaming. The accuracy of the simulation results was verified by physical experiments of glycerol aqueous solution and tracer particles.

A semisolid slurry of Mg98.5Ni0.5Y1.0 alloy was prepared by UV (ultrasonic vibration) method, then the slurry was cast under different squeeze pressures, in which the pressure varied from 0 MPa to 400 MPa. The results show that the primary α-Mg phase and LPSO structure (Long Period Stacking Ordered structure) of the alloy can be refined significantly. The solid solubility of Y and Ni elements in magnesium matrix can be increased with higher pressure, and the Mg2Ni particles is also precipitated out in LPSO structure under pressure. The grain size is decreased with the enhancement of squeeze pressure, which improves the strength. The alloy squeeze cast under pressure of 100 MPa has the highest cost performance. Its yield strength, tensile strength and elongation are 115 MPa, 243 MPa and 13.5%, and they are increased by 21.5%, 9.0% and 16.4% respectively compared with the alloy without applied pressure.

AlN has high thermal conductivity (TC) and low coefficient of thermal expansion (CTE), which is an ideal reinforcement phase for strengthening the thermophysical properties of magnesium alloys to be used as packaging substrate material. However, the poor wettability between AlN and magnesium melt makes the preparation of AlN/Mg composites with high AlN content very difficult. In this work, the AlN/Mg-5Zn-4.9Cu composites were prepared by semi-solid stir casting method to address this problem, and the effect of AlN particle content on the thermophysical properties of the composites was investigated. The results show that AlN can reduce the CTE of magnesium alloy significantly and weaken the TC of magnesium alloys slightly. When 20 wt.% of AlN was added, the TC of the composites was 125.1 W/(m·K) and the CTE was only 19.83×10-6 K-1, which was 26.7% lower than that of the matrix alloy.

In this letter, an improved Ga2O3 solar-blind photodetector is introduced. Using the Ga2O3 thin film grown by metalorganic chemical vapor deposition, the localized surface plasmon resonance enhanced solar-blind photo-response is discussed in view of light absorbance and carrier injection. By introducing Pt nanoparticles to decorate the Ga2O3 photodetector, the responsivity, detectivity, and external quantum efficiency are increased from 0.13 A/W, $4.8\times 10^{{11}}$ Jones and 65% to 4.49 A/W, $8.66\times 10^{{12}}$ Jones and 2196%, respectively. Basically, optimal Pt nanoparticles could resonance with Ga2O3 at around 250 nm light irradiation, exciting the excess electrons to inject into the Ga2O3 thin film; during this process, the photon absorbance and effective carrier injection render the enhancement of detector, so long as the photon energy could generate the electron-hole pairs; due to the light-induced non-equilibrium state. Meanwhile, the absorbance peak resonance enhanced the interaction between photons and Ga2O3. As an effective pathway to boost solar-blind photodetector, this work provides a simple and feasible route to improve the photo-response based on wide bandgap semiconductor Ga2O3.

Microstructure, mechanical properties and phase transformation of a heat-resistant rare-earth (RE) Mg-16.1Gd-3.5Nd-0.38Zn-0.26Zr-0.15Y (wt.%) alloy were investigated. The as-cast alloy is composed of equiaxed α-Mg matrix, net-shaped Mg5RE and Zr-rich phases. According to aging hardening curves and tensile properties variation, the optimized condition of solution treatment at 520 °C for 8 h and subsequent aging at 204 °C for 12 h was selected. The continuous secondary Mg5RE phase predominantly formed at grain boundaries during solidification transforms to residual discontinuous β-Mg5RE phase and fine cuboid REH2particles after heat treatment. The annealed alloy exhibits good comprehensive tensile property at 350 °C, with ultimate tensile strength of 153 MPa and elongation to fracture of 6.9%. Segregation of RE elements and eventually RE-rich precipitation at grain boundaries are responsible for the high strength at elevated temperature.

The influence of squeeze casting pressure on nanoparticle distribution and mechanical properties of 2 wt.% nano-SiCp/Al−Cu composites assisted with ultrasonic vibration was investigated. Results show that as the applied pressure increases from 0 to 400 MPa, the α(Al) grains are significantly refined at first and then the refinement trend slows down, and the porosity of composites is gradually reduced. When the applied pressure is 400 MPa, α(Al) grain size is reduced from 105 to 25 μm, and the nanoparticle distribution is significantly improved, resulting in the optimal mechanical properties of the composites. The ultimate tensile strength, yield strength and elongation of the composites are 290 MPa, 182 MPa and 10%, which are 52.6%, 25.5% and 400% higher than those of the nano-SiCp/Al−Cu composites prepared by gravity casting (0 MPa). The enhancement in strength and elongation of nano-SiCp/Al−Cu composites under high pressure is mainly attributed to grain refinement, reduction of porosity and uniform distribution of nanoparticles.

To quantify the disturbance range of the metal ore caving method, a new method to predict the disturbance range based on rock mechanics parameters is proposed. By combining the rock mechanics index with random medium theory, the prediction correction formula of the disturbance range is established. Based on disturbance equivalent centre and disturbance attenuation sphere, the two-dimensional safety criterion of mining disturbance in metal mines is derived. The new method is applied to 6 mines and the Jianshan Iron Mine, and the numerical simulation of the Jianshan Iron Mine by FLAC3Dmodel is performed. The posteriori error ratio between predicted value and measured value is 0.0357, and the multi-factor cross analysis shows that the relative error of this method to the result is only 0.078. It is found that the method has high prediction accuracy and does not significantly affect the security.

The LPSO structure reinforced magnesium alloy with low Y and Ni contents can achieve the best balance between performance and cost. To further improve the comprehensive mechanical properties, doping with Al element and ultrasonic vibration treatment are feasible approaches. The microstructure of low Y and Ni containing Mg98Y1.0Ni0.5Al0.5alloy with Al addition and the effect of ultrasonic vibration on the microstructure and mechanical properties were studied by SEM−EDS, TEM, XRD and nano-indentation. Doping Al into the alloy decreases the amount of LPSO structure, and Al2NiY phases with radial morphology precipitate near the block LPSO structure. The Al2NiY phase is non-coherent with LPSO structure and Mg matrix at the phase interfaces. The Al2NiY phase can be effectively modified into short flakes and distributed uniformly in the matrix with ultrasonic vibration treatment. The mechanical properties of Mg98Y1.0Ni0.5Al0.5alloy are improved by reducing the generation of microcracks and preventing their propagation. Compared with Mg98Ni0.5Y1.0Al0.5alloy without ultrasonic vibration treatment, the ultimate tensile strength and elongation of the alloy with ultrasonic vibration treatment are improved to 187 MPa and 7.9%, with increments of 21.4% and 105.7%, respectively.

A highly multifunctional antenna with multilinear polarizations (MLPs) and multibands (MBs) is proposed, which can operate over four reconfigurable frequency bands, each band having 16 switchable linear polarizations (LPs) at an 11.25° interval. The larger number of MLPs is achieved by developing an odd–even switching strategy for the independently controlled p-i-n diodes placed between the inner patch and outer sector patches. The diode control is enabled by a field programmable gate array (FPGA) with an engineered biasing network. Moreover, the reported antenna can switch among four continuous bands for each LP, covering a combined range larger than 35%. It is an attractive feature, yet a challenging task for an antenna with such a large number of MLPs. This is realized by utilizing a double-layer feeding strategy with appropriate sector-patch activation, which is particularly appealed to such a highly multifunctional antenna. Furthermore, the antenna has a rotational symmetry along the azimuthal direction and, hence, all the LPs show almost rotationally invariant pattern shapes and gains. The measured results are consistent with the simulated ones, commonly validating the effectiveness of our design.

Ultraviolet (UV) photodetectors have received a significant amount of attention in a variety of areas; especially, self-powered photodetectors are anticipated to address the energy-saving demand in the astronautics under the photovoltaic effect. In this work, a Ga-doped ZnO (ZnO:Ga)/Al $_{{0}.{1}}$ Ga $_{{0}.{9}}\text{N}$ (AlGaN) heterojunction is introduced for performing UV photodetector, which is enhanced by the pyro-photoelectric effect coupling of pyroelectric and photovoltaic effects. The heterojunction UV photodetector can operate in a self-powered mode with aresponsivity of 0.063 mA $\text{W}^{-{1}}$ under the illumination of $135 \mu \text{W}$ cm $^{-{2}}$ . More importantly, after pyro-photoelectric enhancement, the photocurrent is effectively increased from 13 to 45 pA. Additionally, under the illumination of $493 \mu \text{W}$ cm $^{-{2}}$ , the photo-to-dark-current ratio (PDCR) of 80 and ${{1}.{7} \times {10}}^{{4}}$ is obtained at a reverse bias of −10 V and forward bias of +10 V, respectively, indicating that the heterojunction UV photodetector can be regarded as a dual-mode photodetector since it can operate in both forward-biased photoconductive mode and reverse-biased depletion mode. Moreover, the UV photodetector exhibits a fast temporal pulsed laser response with a rising time of 0.79 ms and a decay time of 9.4 ms. In all, this work presents a novel strategy for the advancement of UV detection.

Fluorescence imaging is a useful tool in the field of biomedical applications. However, its imaging capacity is limited by the depth of tissue that can be penetrated when using visible light (400–700 nm) or the first near-infrared window (NIR-I, 700–900 nm). To overcome the problem, fluorescence imaging in the second near-infrared window (NIR-II, 1000–1700 nm) has been developed to reduce photon scattering, auto-absorption and tissue autofluorescence to achieve high spatiotemporal resolution and deep imaging penetration. The key to NIR-II imaging is obtaining and analyzing highly selective information from functional fluorophores that emit in the 1000–1700 nm range. With the rapid development of multidisciplinary research, various types of NIR-II fluorophores have been produced and used in non-invasive, real-time NIR-II biomedical applications. This review summarizes some of the most prevalent NIR-II fluorophores and their synthesis, such as organic fluorophores (OFs), single-walled carbon nanotubes (SWCNTs), quantum dots (QDs), and rare-earth nanoparticles (RENPs). On this basis, we describe the applications of these fluorophores in biomedical fields, including bioimaging, biosensing, phototherapy and surgical navigation. Additionally, major challenges and prospects of NIR-II biomedical application will be further explored.

As a ceramic material, AlN has very good thermophysical and mechanical properties. In addition, AlN is an effective refining agent for Mg alloys because it has a lattice constant similar to that of Mg. Therefore, AlN is an ideal reinforcement for magnesium matrix composites (MMCs), and is attracting increasing attention. This review addresses the development of preparation technologies for AlN-reinforced Mg matrix composites. The mainstream preparation techniques include stir casting, melt infiltration, powder metallurgy, and in-situ methods. In addition, the advantages and disadvantages of these techniques are analyzed in depth, and it is pointed out that the next direction for the preparation of high-performance AlN-reinforced MMCs is less aluminization and multiple technologies integration.

Organic–inorganic hybrid materials are easy to modify, which makes it possible to construct multifunctional ferroelectrics directionally and apply the built-in electric field and switching properties of ferroelectrics to multidisciplinary fields. Particularly, the coupling of photoluminescence and ferroelectricity in a single hybrid material facilitates its novel applications in lighting sensors, memory devices, and other multifunctional applications. Based on the photoluminescent molecule 4-(2-aminoethyl) morpholine (AEM), here, a room-temperature ferroelectric (C6H16N2O)CdBr4·H2O (AEM-CdBr4) is designed and obtained, which crystallizes in a polar orthorhombic space group of Pca21. A reversible ferroelectric–paraelectric phase transition was confirmed at 353 K through experimental results, such as differential scanning calorimetry (DSC) curves, variable-temperature Raman spectroscopy, and photoluminescence (PL) spectroscopy. The crystal exhibits ferroelectricity at room temperature with a saturation polarization of approximately 8 μC/cm2. The photoluminescence of compound AEM-CdBr4is mainly derived from the monomeric fluorescence emission of the AEMmolecule and is not directly related to the energy band structure of the crystal. This room-temperature molecular-type ferroelectric AEM-CdBr4with photoluminescence will provide new ideas for the design of new multifunctional ferroelectrics.

Maximizing the therapeutic capacity of drugs by allowing them to escape lysosomal degradation is a long-term challenge for nanodrug delivery. Japanese encephalitis virus (JEV) has evolved the ability to escape the endosomal region to avoid degradation of internal genetic material by lysosomes and further induce upregulation of cellular autophagy for the purpose of their mass reproduction. In this work, to exploit the lysosome escape and autophagy-inducing properties of JEV for cancer therapy, we constructed a virus-mimicking nanodrug consisting of anti-PDL1 antibody-decorated JEV-mimicking virosome encapsulated with a clinically available autophagy inhibitor, hydroxychloroquine (HCQ). Our study indicated that the nanodrug can upregulate the autophagy level and inhibit the autophagic flux, thereby inducing the apoptosis of tumor cells, and further activating the immune response, which can greatly improve the antitumor and tumor metastasis suppression effects and provide a potential therapeutic strategy for tumor treatment.

Developing small‐molecule photothermal agents (PTAs) with good near‐infrared‐II (NIR‐II) response for deeper tissue penetration and minimizing damage to healthy tissues has attracted much attention in photothermal therapy (PTT). However, concentrating ultra‐long excitation wavelengths and high photothermal conversion efficiencies (PCEs) into a single organic small molecule is still challenging due to the lack of suitable molecular structures. Here, six polymethine cyanine molecules based on the structure of indocyanine green are synthesized by increasing the conjugated structure of the two‐terminal indole salts and the number of rigid methine units, and incorporating longer alkyl side chains into the indole salts. Ultimately, IC‐1224 is obtained with an absorption wavelength of more than 1200 nm, which has a high PCE up to 83.2% in the NIR‐II window and exhibits excellent PTT tumor ablation performance. This provides a high‐performance NIR‐II‐responsive PTA, and offers further possibilities for the application of PTT in biomedical fields. IC‐1224 is synthesized with an absorption wavelength of more than 1200 nm, which has a photothermal conversion efficiency of 83.2% in the NIR‐II window and exhibits excellent photothermal therapy (PTT) tumor ablation performance. This high‐performance NIR‐II‐responsive photothermal agent provides more possibilities for the in‐depth application of PTT in biomedical fields.

Mammalian cell display technology uses eukaryotic protein expression system to display proteins on cell surfaces and has become an important method in biological research. Although mammalian cell display technology has many advantages and development potential, certain attributes of the displayed protein remain uncharacterized, such as whether the displayed proteins re-enter the cell and how displayed proteins move into the cell. Here, we present the endocytosis mechanism, motility behavior, and transport kinetics of displayed proteins determined using HaloTag as the displayed protein and quantum dot-based single-particle tracking. The displayed protein enters the cell through clathrin-mediated endocytosis and is transported through the cell in three stages, which is dependent on microfilaments and microtubules. The dynamic information obtained in this study provides answers to questions about endocytosis and postendocytosis transport of displayed proteins and, therefore, is expected to facilitate the development of surface display technology.

Nuclear trafficking of viral genome is an essential cellular process in the life cycles of viruses. Despite substantial progress in uncovering a wide variety of complicated mechanisms of virus entry, intracellular transport of viral components, virus assembly, and egress, the temporal and spatial dynamics of viral genes trafficking within the nucleus remains poorly understood. Herein, using single-particle tracking, we explored the real-time dynamic nuclear trafficking of influenza A virus (IAV) genes packaged as the viral ribonucleoprotein complexes (vRNPs) by combining a four-plasmid DNA transfection system for the reconstruction of green fluorescent protein (GFP)-labeled vRNPs and a spinning disk super-resolution fluorescence microscope. We found that IAV infection significantly induced the formation of actin microfilaments (F-actin) in the nucleus. In combination with the fluorescent protein-tagged nuclear F-actin probe, we visualized the directed movement of GFP-labeled vRNPs foci along the nuclear F-actin with a speed of 0.18 μm/s, which is similar to the microfilaments-dependent slow directed motion of IAVs in the cytoplasm. The disruption of nuclear F-actin after treatment with microfilament inhibitors caused a considerable decrease in vRNPs motility and suppressed the nuclear export of newly produced vRNPs, indicating that the slow, directed movement plays a crucial role in facilitating the nuclear egress of vRNPs. Our findings identified a nuclear F-actin-dependent pathway for IAV vRNPs transporting from the nucleus into the cytoplasm, which may in turn uncover a novel target for antiviral treatment.

Abstract and Key Results * The last two decades have witnessed an unprecedented transfer of Western management education theories and pedagogies into China and most Chinese MBA programs are now [...]

A study was conducted to examine the strategy -performance consequences of strategic group membership and attempted by mistake to investigate the relationship between the profitability of Taiwan's IC firms and both firm's business strategies and industrial business cycles. It implied that the effectiveness of virtual integration to increase a firm's return on assets and return on equity existed at any stage of business cycles.

POLAR-2 is a gamma-ray burst (GRB) polarimeter that is designed to study the polarization in GRB radiation emissions, aiming to improve our knowledge of related mechanisms. POLAR-2 is expected to utilize an on-board polarimeter that is sensitive to soft X-rays (2–10 keV), called low-energy polarization detector. We have developed a new soft X-ray polarization detector prototype based on gas microchannel plates (GMCPs) and pixel chips (Topmetal). The GMCPs have bulk resistance, which prevents charging-up effects and ensures gain stability during operation. The detector is composed of low outgassing materials and is gas-sealed using a laser welding technique, ensuring long-term stability. A modulation factor of 41.28% ± 0.64% is obtained for a 4.5 keV polarized X-ray beam. A residual modulation of 1.96% ± 0.58% at 5.9 keV is observed for the entire sensitive area.

There is little datum related to microstructure and properties of Mg alloys squeeze-casted with pressure over 200 MPa. In this study, the microstructure and properties of Mg-6Zn-1.4Y (ZW61) alloy solidified under 100MPa to 800MPa were investigated. The results show that a remarkable microstructure refinement and porosity reduction can be reached through solidification under high pressure. The average grain size and the volume fraction of second phase, i.e. quasicrystal I-phase, decrease continuously with the increase of applied pressure. The tensile properties, especially elongation, are obvious enhanced because of the microstructure refinement and castings densification under high pressure. The ultimate tensile strength and elongation of ZW61 alloy in as-cast state are 243 MPa and 18.7% when the applied pressure is 800 MPa, which are increased by 35% and 118% respectively, compared with that of the gravity castings.