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The exotic electronic properties of topological semimetals (TSs) have opened new pathways for innovative photonic and optoelectronic devices, especially in the highly pursuit terahertz (THz) band. However, in most cases Dirac fermions lay far above or below the Fermi level, thus hindering their successful exploitation for the low-energy photonics. Here, low-energy type-II Dirac fermions in kitkaite (NiTeSe) for ultrasensitive THz detection through metal-topological semimetal-metal heterostructures are exploited. Furthermore, a heterostructure combining two Dirac materials, namely, graphene and NiTeSe, is implemented for a novel photodetector exhibiting a responsivity as high as 1.22 A W

Ovarian cancer is the most lethal gynecological cancer. In spite of recent advances, clinical outcomes remain poor, urgently needing novel therapeutic approaches. Growing evidence indicates that microRNAs play crucial roles in ovarian carcinogenesis and progression and that ferroptosis serves as a novel tumor suppressor. However, the molecular mechanisms of miRNA-mediated ferroptosis regulation in ovarian cancer are still largely unknown. In the present study, we show that miR-424-5p negatively regulates ferroptosis by directly targeting ACSL4 in ovarian cancer cells. Upregulation of miR-424-5p suppressed ACSL4 by directly binding to its 3'-UTR, which subsequently reduced erastin- and RSL3-induced ferroptosis. Meanwhile, knockdown of miR-424-5p increased the sensitivity of ovarian cancer cells to erastin and RSL3. Furthermore, ACSL4 was upregulated in ovarian cancer tissues, and high ACSL4 expression predicted worse prognosis and sensitized ovarian cancer cells to erastin- and RSL3-induced ferroptosis. Importantly, decreases in lipid peroxides and ferroptotic cell death mediated by miR-424-5p could be abrogated by ACSL4 overexpression. Taken together, our findings demonstrate that miR-424-5p regulates ferroptosis by targeting ACSL4 in ovarian cancer cells and suggest a potential therapeutic approach for ovarian cancer.

For a long time, the embedded industry has been constrained by CPU performance, ROM and RAM capacity and other factors, so the software scale cannot be built too large. The new embedded designers often overturn the original version because they cannot comprehend the previous code. The lack of software framework standard leads to redundant and useless work. By making the analogy to the hierarchical idea of Android architecture, this paper proposes a simple and practical software architecture suitable for the embedded industry. The architecture adopts hierarchical design and each module operates independently, thus realizes high cohesion and low coupling of the system. The C structure variable is used to simulate the properties of the class, and the function pointer is used to replace the function in the class. By doing this, embedded programming changes from process-oriented to object-oriented. In addition, the architecture provides a registration mechanism to solve the upload of high-speed, real-time changing data.

Here we report a metal-insulator-metal (MIM) based infrared plasmonic metamaterial absorber consisting of deep subwavelength meander line nanoantennas. High absorption composed of two-hybrid modes from 11 μm to 14 μm is experimentally demonstrated with a pixel pitch of 1.47 μm corresponding to a compression ratio of 8.57. The physical mechanisms responsible for novelty spectral absorption, including the strong coupling between the plasmon resonances and the phonon vibrations, material loss from the dielectric spacer, localized surface plasmon resonance (LSPR), and Berreman mode excited by oblique incidence, have been systematically analyzed by finite-difference time-domain (FDTD) method, Fabry-Perot resonance model and two-coupled damped oscillator model. At oblique incidence, a spectral splitting related to the strong coupling between LSPR mode and Berreman mode is also observed. The distribution of local electromagnetic fields and ohmic loss are numerically investigated. Moreover, we evaluate the absorption performances with finite-sized arrays. We also show that the absorber can maintain its absorption with a 2 × 2 nanoantenna array. Such a miniaturized absorber can adapt to infrared focal plane arrays with a pixel size smaller than 5 μm, and thermal analysis is also performed. Our approach provides an effective way to minimize the antenna footprint without undermining the absorber performances, paving the way towards its integration with small pixels of infrared focal plane arrays for enhanced performances and expanded functionalities.

In this letter, a hyperspectral light detection and ranging (HSL) with 10-nm spectral resolution was designed and tested using a supercontinuum laser source. The major difference between the prototyped HSL and similar instruments was that a liquid crystal tunable filter (LCTF) was installed before the avalanche photodiode detector and utilized as a spectroscopic device. The design allowed continuous wavelength selection of the backscattered echoes in the time dimension. Moreover, for general accuracy evaluation of range measurement and spectral measurement, laboratory experiments for vegetation red edge detection were performed using the prototyped HSL to assess its feasibility on agriculture application. Yellow and green leaves from aloe and dracaena plants were measured by the LCTF-HSL for detecting the corresponding “red edge” position. Spectral profiles measured by an SVC-HR-1024 spectrometer which is designed by SVC company were used as a reference to evaluate the measurements of HSL. The comparison results showed that the red edge positions extracted from the two individual measurements were similar, thus indicating that the LCTF-based high-resolution HSL was effective for this application.

We report a rapid and precise spectral determination approach based on visually patterned integrated narrow bandpass filters. The wavelength of light can be determined accurately even by naked eyes in the aid of the device. The experimental results show that both the light with single wavelength and a spectral range can be distinguished rapidly and precisely by naked eyes with spectral resolution higher than 7 nm, which can be even higher than 1 nm with the intended design. It is a very robust and stable way to keep the filtering wavelengths constant and remarkably improves the stability superior to conventional methods. It can be used for high-throughput identification of light source and food safety detection related applications.

In precision agriculture, efficient fertilization is one of the most important pursued goals. Vegetation spectral profiles and the corresponding spectral parameters are usually employed for vegetation growth status indication, i.e., vegetation classification, bio-chemical content mapping, and efficient fertilization guiding. In view of the fact that the spectrometer works by relying on ambient lighting condition, hyperspectral/multi-spectral LiDAR (HSL/MSL) was invented to collect the spectral profiles actively. However, most of the HSL/MSL works with the wavelength specially selected for specific applications. For precision agriculture applications, a more feasible HSL capable of collecting spectral profiles at wide-range spectral wavelength is necessary to extract various spectral parameters. Inspired by this, in this paper, we developed a hyperspectral LiDAR (HSL) with 10 nm spectral resolution covering 500~1000 nm. Different vegetation leaf samples were scanned by the HSL, and it was comprehensively assessed for wide-range wavelength spectral profiles acquirement, spectral parameters extraction, vegetation classification, and the laser incident angle effect. Specifically, three experiments were carried out: (1) spectral profiles results were compared with that from a SVC spectrometer (HR-1024, Spectra Vista Corporation); (2) the extracted spectral parameters from the HSL were assessed, and they were employed as the input features of a support vector machine (SVM) classifier with multiple labels to classify the vegetation; (3) in view of the influence of the laser incident angle on the HSL reflected laser intensities, we analyzed the laser incident angle effect on the spectral parameters values. The experimental results demonstrated the developed HSL was more feasible for acquiring spectral profiles with wide-range wavelength, and spectral parameters and vegetation classification results also indicated its great potentials in precision agriculture application.

In this paper, a Janus metasurface is designed by breaking the structural symmetry based on the polarization selection property of subwavelength grating. The structure comprises three layers: a top layer having a metallic nanostructure, a dielectric spacer, and a bottom layer having subwavelength grating. For a forward incidence, the metal-insulator-metal (MIM) structure operates as a gap plasmonic cavity if the linearly polarized (LP) component is parallel to the grating wires. It also acts as a high-efficiency dual-layer grating polarizer for the orthogonal LP component. For the backward incidence, the high reflectance of the grating blocks the function of the gap plasmonic cavity, leading to its pure functioning as a polarizer. A bifunctional Janus metasurface for 45 degrees beam deflector and polarizer, with a transmission of 0.87 and extinction ratio of 3840, is designed at 1.55 μm and is investigated to prove the validity of the proposed strategy. Moreover, the proposed metasurface can be cascaded to achieve more flexible functions since these functions are independent in terms of operational mechanism and structural parameters. A trifunctional Janus metasurface that acts as a focusing lens, as a reflector, and as a polarizer is designed based on this strategy. The proposed metasurface and the design strategy provide convenience and flexibility in the design of multifunctional, miniaturized, and integrated optical components for polarization-related analysis and for detection systems.

Optical coatings are usually applied to tailor the transmission, reflection, or absorption spectral properties, such as conventional antireflection, bandpass, longpass (or shortpass) filters. There are novel applications developed in recent years, in the aid of micro and nanotechnologies. Among them, the integrated filter device has already been successfully applied in space for the first time. This chapter will introduce some new applications of optical coatings on spectral selective structures including the wavelength division components for miniature spectrometer, blue filters for visible light communications, fractal independently tunable multichannel filters, broadband perfect absorbers, and spectrally selective solar absorbers. The whole chapter is composed of five sections. In each section, the corresponding fundamental principles, preparing processes, present research, and practical application situations are reviewed.

Background: Chronic atrophic gastritis (CAG) is an established precursor of gastric carcinoma with high prevalence worldwide. It is a typical complex gastro-intestinal disease with multiple influence factors, of which exact mechanisms remain unelucidated. Therefore, an ideal strategy to relieve CAG is urgently needed. In recent years, massage therapy has been increasingly accepted by CAG patients due to its lower costs, fewer unwanted side effects and safety for clinical use. In this systematic review, we aim to evaluate the effectiveness and safety of massage therapy for patients with chronic atrophic gastritis. Methods: We will search the following electronic databases for randomized controlled trials to evaluate the effectiveness and safety of massage therapy in treating chronic atrophic gastritis: Wanfang and Pubmed Database, China National Knowledge Infrastructure Database, Cochrane Central register of controlled trials, Cumulative Index of Nursing and Allied Health Literature, and Excerpta Medica database. Each database will be searched from inception to September 2020. The entire process will include study selection, data extraction, risk of bias assessment, and meta-analyses. Result: This proposed study will evaluate the effectiveness and safety of massage therapy for patients with chronic atrophic gastritis. The outcomes will include changes in CAG relief and adverse effect. Conclusion: This proposed systematic review will evaluate the existing evidence on the effectiveness and safety of massage therapy for patients with chronic atrophic gastritis. Dissemination and ethics: The results of this review will be disseminated through peer-reviewed publication. Because all of the data used in this systematic review and meta-analysis has been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process.

Summary Structural colors are colors generated by the interaction between incident light and nanostructures. Structural colors have been studied for decades due to their promising advantages of long-term stability and environmentally friendly properties compared with conventional pigments and dyes. Previous studies have demonstrated many artificial structural colors inspired by naturally generated colors from plants and animals. Moreover, many strategies consisting of different principles have been reported to achieve dynamically tunable structural colors. Furthermore, the artificial structural colors can have multiple functions besides decoration, such as absorbing solar energy, anti-counterfeiting, and information encryption. In the present work, we reviewed the typical artificial structural colors generated by multilayer films, photonic crystals, and metasurfaces according to the type of structures, and discussed the approaches to achieve dynamically tunable structural colors., Graphical Abstract, Public summary • Structural colors are colors generated by the interaction between incident light and nanostructures • High-resolution and long-term stable structural colors, can be designed as functional devices • Structural colors have application prospects in many fields, such as high-resolution printing and anti-counterfeiting

We demonstrated strong fluorescence blinking on large all-inorganic perovskite (CsPbBr3) nano-spheres. By performing (time-resolved) micro-photoluminescence (μ-PL) measurements, the unique blinking characteristics of the as-grown nano-spheres with diameters of hundred nanometers, are clearly observed. Blinking has no obvious on/off states, which is different from the blinking characteristics of quantum dots. It is believed that the blinking of fluorescence is caused by metastable defect-induced trapping of carriers on the surface of the nano-spheres, because dramatically suppressed fluorescence blinking and the decay rates of ultrafast carriers are realized by surface passivation of the nano-spheres. Surface defects are closely related to the ambient atmosphere, which has been further confirmed by PL measurements of the as-grown nano-spheres in vacuum. Additionally, we also found that the fluorescence blinking was significantly suppressed as the sample size increased, which can be attributed to the large-size induced average effect on fluorescence blinking. These results may be important for understanding the mechanism of the fluorescence blinking of perovskite materials and for developing optical devices with good fluorescence stability.

Remediation of soil heavy metal by biochar has been extensively studied. However, few studies focused on the role of biochar on the co-immobilization of cadmium (Cd(II)) and arsenate (As(V)) and related soil nutrient availability. Remediation tests were conducted with three types of pristine and ferric trichloride (FeCl3) modified biochar (rice, wheat, and corn straw biochar) in Cd-As co-contaminated soil, with application rates of 1, 5, and 10% (w/w) and the incubation of 1, 7, 10, and 15 days. Using TCLP (Toxicity Characteristic Leaching Procedure) method, 10% of FeCl3 modified corn-straw derived biochar (FCB) had the highest immobilization efficiency of Cd(II) (63.21%) and As(V) (95.10%) after 10 days of the incubation. Iron-modified biochar immobilized higher fractions of water-soluble (F1) and surface-absorbed (F2) metal fractions than pristine biochar. For FCB amendment, Cd was mostly presented in the organic matter (OM) and sulfides associated (F4) and residual (F5) fractions (88.52%), as was found in the Fe-Al (oxides and hydroxides) (F3), F4, and F5 fractions (75.87%). FCB amendment increased soil pH values and available iron contents (p &lt, 0.05), while no changes in soil available phosphorus content (p &gt, 0.05). This study showed that FCB application reduces the environmental mobility of metals in Cd-As contaminated soil, while it also increases soil pH and available nutrient mobility, improving soil environmental quality and reducing remediation costs.

The detection of terahertz electromagnetic waves is crucial for emerging applications within this frequency band, such as spectroscopy, imaging, and communication. Extending the well-developed uncooled infrared focal plane array technology to terahertz frequency regime would be very attractive, but high absorption in the terahertz region with a subwavelength pixel is necessary. In this paper, we proposed a meander line nanoantenna (MLNA) absorber with a metal-insulator-metal structure for subwavelength terahertz absorption. 89% absorption is achieved at the wavelength of 155 μm with a 10 μm pitch size. The MLNA absorber is polarization insensitive and can maintain a high absorption when the incident angle is within 40°. We expect that the proposed MLNA absorber can be integrated with the small pixels of uncooled infrared focal plane array for terahertz detection.

The terahertz (THz) technique is still confronted with challenges partly due to lack of an efficient method to achieve sensitive detection at room temperature. Gapless graphene is highly sought-after as a potential candidate for active material in photo-detection across the whole electromagnetic spectrum. However, the efficient photo-to-electric conversions within THz range are not well-developed at present. Here we report the hot carrier-assisted photoconduction being triggered by a sub-THz electromagnetic wave in homogeneous graphene, which is beyond the conventional interband mechanism and can be potentially extended to the higher THz band. The photoconductive effect here is attributed to the additional carriers replenished from the electrode following the potential disturbance of the hot carrier diffusion, which depletes or increases the sheet density in the channel depending on the carrier-polarity in the channel. The biased photoconductive device shows sensitivity over 400 V/W (4 × 103 V/W) at room temperature and noise-equivalent power less than 0.5 nW/Hz0.5 (20 pW/Hz0.5) in reference to the incident (absorbed) power. The reported figures of merit represent the benchmark for further performance improvement via several different methods such as shortening the channel, using a matched antenna or material with improved mobility. All results presented open up the feasibility of achieving a photoconductive device for sensitive room temperature detection at terahertz frequencies.

Therapeutic vaccine is a promising approach in cancer therapy. But tumor-associated antigen peptides have weak immunogenicity and cancer patients are often characterized by immunosuppression and tolerance, leading to less efficiency of immunotherapy. We here successfully developed indoleamine 2, 3-dioxygenase (IDO) siRNA nanoparticle-coated and tyrosinase-related protein 2 (Trp2)-displayed recombinant Saccharomyces cerevisiae (YCP). YCPs had positive charges with a diameter of approximately 5μm, resulting in selective phagocytosis by APC cells. YCP-delivered siRNA and Trp2 successfully escaped from phagosomes, efficiently inhibited IDO expression in DCs, promoted the immune reaction of T cell against Trp2, increased the secretion of proinflammatory cytokines such as IFN-γ,TNF-α, and IL-6, and decreased the generation of regulatory T cells. Moreover, YCPs significantly inhibited melanoma tumor growth by alleviating immune tolerance and promoting Trp2-specific CD8+ T cell immune response. These results suggest that Saccharomyces cerevisiae as a combined immunotherapeutic platform to simultaneously delivery IDO-siRNA and Trp2 epitope peptide is a promising vaccine system for melanoma treatment.

In this paper, a strategy to achieve a simultaneous wavefront shaping and polarization rotation, without compromising the number of pixels and energy efficiency as well as having broadband operation range, is proposed. This strategy is based on the application of a spin-decoupled phase metasurface composed by only one set of metal-insulator-metal (MIM) umbrella-shaped chiral unit cells. Quasi-non-dispersive and spin-decoupled phase shift can be achieved simply by changing single structural parameter of the structure. By further merging the Pancharatnam-Berry (PB) geometric phase, conversion of an incident LP light beam into right- and left-handed circularly polarized reflected beams with similar amplitudes, desired phase profiles and controlled phase retardation on a nanoscale is enabled with high efficiency. Based on the proposed strategy, a polarization-insensitive hologram generator with control optical activity, and a multiple ring vortex beam generator are realized. The results obtained in this work provide a simple and pixel-saving approach to the design of integratable and multitasking devices combining polarization manipulation and wavefront shaping functions, such as vectorial holographic generators, multifocal metalenses, and multichannel vector beam generators.

Background β-Amyloid peptide (Aβ) oligomers are initial factors used to induce Alzheimer’s disease (AD) development, and Aβ monomers have normal physiological function. The antibodies or vaccines against Aβ monomers have serious problems, such as side effects and low curative effects. Therefore, it is essential to specifically target Aβ oligomers rather than monomers for the treatment of AD. Methods The mimotopes of Aβ oligomers were obtained by panning the phage-displayed random peptide libraries using oligomer-specific antibodies as targets and expressed on the surface of EBY100 Saccharomyces cerevisiae to generate yeast cell base vaccines. One vaccine (AOE1) induced antibodies specifically against Aβ oligomers and was selected for further study. The APP/PS1 mice were subcutaneously immunized with AOE1 eight times. The levels and characteristics of antibodies induced by AOE1 were determined by enzyme-linked immunosorbent assay. The effect of AOE1 on the cognitive deficits of AD mice was tested by novel object recognition (NOR) and Y-maze. Dot blot analysis, Western blot analysis, and immunohistochemistry were applied to measure the effects of AOE1 on Aβ pathologies, neuroinflammation, and microhemorrhages in the brains of AD mice. Results Eight mimotope candidates of Aβ oligomers were selected and expressed on EBY100 S. cerevisiae. Only AOE1 vaccine containing mimotope L2 induced antibodies that specifically recognized Aβ42 oligomers rather than monomers. AOE1 immunization significantly increased the AD mice’s exploration times for the novel object in the NOR test and the choices for new arms in the Y-maze test, and it reduced levels of Aβ oligomers and glial activation in the AD mouse brains. No activation of Aβ-specific T cells and microhemorrhages was observed in their brains following AOE1 vaccination. Conclusions AOE1 is the first vaccine applying the oligomer-specific mimotope as an immunogen, which could induce antibodies with high specificity to Aβ oligomers. AOE1 immunization attenuated Aβ pathologies and cognitive deficits in AD mice, decreased the overactivation of glial cells, and did not induce microhemorrhage in the brains of AD mice. These findings suggest that AOE1 may be a safer and more effective vaccine for AD treatment.

Railway rolling stock is one of the most expensive assets of railway operators. Efficient utilization of rolling stock is one of the most important objectives pursued in practice. This research focuses on the improvement in rolling stock rostering efficiency for high-speed rail system. According to the circulation schedule and long-term maintenance plan, the rostering planner decides the assignment between rolling stock and duties subject to a set of practical constraints. Owing to its complexity, this task remains a manual process at the Taiwan High Speed Rail Corporation. Experienced railway practitioners can generally create a good and feasible plan, but they cannot guarantee optimality of the solution considering only short-term process. In this research, we developed an exact optimization model and a heuristic method to automate this process and improve the efficiency of rolling stock utilization. Results from the case studies demonstrate that the efficiency of the rolling stock usage can be increased by $3\%\sim 4\%$ , and that the process time can be significantly reduced from hours to seconds.

Active immunotherapy has shown promising potential for cancer treatment. However, there still remain major challenges including induction of a potent and specific T-cell response against the endogenous antigen and retention of tumor immunity. To address these problems, we used layered double hydroxide (LDH) nanoparticles (NPs) to co-deliver tyrosinase-related protein 2 (Trp2) and indoleamine 2,3-dioxygenase siRNA (siIDO) to dendritic cells (DCs). These LDH NPs were readily taken in by DCs, and escaped from endosomes into the cytoplasm. Compared with free Trp2 peptide or siIDO, the vaccination with the LDH NPs co-delivering Trp2 and siIDO significantly inhibited tumor growth in melanoma mouse models by relieving IDO-mediated immune suppression and increasing naïve and specific T cell activation process in vivo. Thus, these LDH NPs, which have a high loading capacity for peptide or siRNA effectively protect and deliver Trp2 and siIDO, overcome the immune tolerance and strengthen T cell immunity, are potential therapeutics to enhance cancer treatment.

Thermal radiation with narrow bandwidth and well-defined emission directions is highly sought after for a variety of applications, ranging from infrared sensing and thermal imaging to thermophotovoltaics. Here, a large-area (4-inch-diameter) long-wavelength infrared thermal emitter is presented, which is spectrally selective, highly directional, and easily fabricated. The basic structure of the proposed thermal emitter is composed of a truncated one-dimensional photonic crystal and a continuous metallic film separated by a dielectric spacer. Experimental results show that the emitter exhibits a narrowband thermal emittance peak of 92% in the normal direction at the wavenumber of 943.4 cm−1 with a bandwidth of 12.5 cm−1 and a narrow angular emission lobe with a limited solid angle of 0.325 sr (0.115 sr) for s (p) polarization. Numerical simulation analyses are performed to corroborate the experimental observations. Temporal coupled-mode theory combined with transfer matrix method is employed to analytically investigate the emission properties of the structure, which not only can be used to understand the experimental results, but also plays a certain guidance role in designing a thermal emitter with the desired properties. The present thermal emitter can be implemented for thermal photonics management, allowing applications in thermal imaging and medical systems, etc.

During the mining operation, it is a critical task in coal mines to significantly improve the safety by precision coal mining sorting and rock classification from different layers. It implies that a technique for rapidly and accurately classifying coal/rock in-site needs to be investigated and established, which is of significance for improving the coal mining efficiency and safety. In this letter, a 91-channel hyperspectral LiDAR (HSL) using an acousto-optic tunable filter (AOTF) as the spectroscopic device is designed, which operates based on the wide-spectrum emission laser source with a 5-nm spectral resolution to tackle this issue. The spectra of four-type coal/rock specimens collected by HSL are used to classify with three multi-label classifiers: naive Bayes (NB), logistic regression (LR), and support vector machine (SVM). Furthermore, we discuss and explore whether Gaussian fitting (GF) method and calibration with the reference whiteboard (RB) can enhance the classification accuracy. The experimental results show that the GF technique not only improves the accuracy of range measurement but also optimizes the classification performance using the spectra collected by the HSL. In addition, calibration with RB can improve classification accuracy as well. In addition, we also discuss methods to improve the calibration-free classification accuracy preliminarily. © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.