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BACKGROUND: Guizhou black goat is one of the indigenous black goat breeds in the southwest region of Guizhou, China, which is an ordinary goat for mutton production. They are characterized by moderate body size, black coat, favorite meat quality with tender meat and lower odor, and tolerance for cold and crude feed. However, little is known about the genetic characteristics or variations underlying their important economic traits. RESULTS: Here, we resequenced the whole genome of Guizhou black goat from 30 unrelated individuals breeding in the five core farms. A total of 9,835,610 SNPs were detected, and 2,178,818 SNPs were identified specifically in this breed. The population structure analysis revealed that Guizhou black goat shared a common ancestry with Shaanbei white cashmere goat (0.146), Yunshang black goat (0.103), Iran indigenous goat (0.054), and Moroccan goat (0.002). However, Guizhou black goat showed relatively higher genetic diversity and a lower level of linkage disequilibrium than the other seven goat breeds by the analysis of the nucleotide diversity, linkage disequilibrium decay, and runs of homozygosity. Based on FST and θπ values, we identified 645, 813, and 804 selected regions between Guizhou black goat and Yunshang black goat, Iran indigenous goat, and cashmere goats. Combined with the results of XP-EHH, there were 286, 322, and 359 candidate genes, respectively. Functional annotation analysis revealed that these genes are potentially responsible for the immune response (e.g., CD28, CD274, IL1A, TLR2, and SLC25A31), humility-cold resistance (e.g., HBEGF, SOSTDC1, ARNT, COL4A1/2, and EP300), meat quality traits (e.g., CHUK, GAB2, PLAAT3, and EP300), growth (e.g., GAB2, DPYD, and CSF1), fertility (e.g., METTL15 and MEI1), and visual function (e.g., PANK2 and NMNAT2) in Guizhou black goat. CONCLUSION: Our results indicated that Guizhou black goat had a high level of genomic diversity and a low level of linkage disequilibrium in the whole genome. Selection signatures were detected in the genomic regions that were mainly related to growth and development, meat quality, reproduction, disease resistance, and humidity-cold resistance in Guizhou black goat. These results would provide a basis for further resource protection and breeding improvement of this very local breed.
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Cabras , Selección Genética , Humanos , Animales , Cabras/genética , Genoma , Genómica , Fenotipo , Polimorfismo de Nucleótido Simple , Proteínas Adaptadoras Transductoras de Señales/genéticaRESUMEN
Metamaterials offer exciting opportunities for developing multispectral stealth due to their unique electromagnetic properties. However, currently transparent radar-infrared-visible compatible stealth metamaterials typically involve complex hierarchical designs, leading to thickness and transparency limitations. Here, we propose an integrated metamaterial for multispectral stealth with high transparency. Our design features an ITO/dielectric/ITO sandwich structure, with the upper-layer ITO acting as a resonator for broadband microwave absorption while maintaining a high filling ratio to suppress infrared (IR) radiation. Experimental results demonstrate excellent performance, with over 90% microwave absorption in 8-18â GHz, an IR emissivity of approximately 0.36 in 3-14â µm, an average optical transmittance of 74.1% in 380-800â nm, and a thickness of only 2.4 mm. With its multispectral compatibility, the proposed metamaterial has potential applications in stealth and camouflage fields.
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With the rapid development of communication technology and detection technology, it is difficult for devices operating in a single spectrum to meet the application requirements of device integration and miniaturization, resulting in the exploration of multi-spectrum compatible devices. However, the functional design of different spectra is often contradictory and difficult to be compatible. In this work, a transparent slit circular metasurface with a high filling ratio is proposed to achieve the compatibility of microwave, infrared and visible light. In the microwave, based on the Pancharatnam-Berry phase theory, the continuous amplitude and binary phase can be customized only by rotating the slit angle to achieve an Airy beam function at 8-12â GHz. In the infrared, the mean infrared emissivity is reduced to 0.3 at 3-14â µm by maintaining high conductive filling ratio, and in visible light, based on the transparency of materials, the mean transmittance can achieve 50% at 400-800â nm. All the results can verify the multi-spectral compatibility performance, which can also verify the validity of our design method. Importantly, the multi-spectral compatible metasurface contributes an option for multifunctional integration, which can be further applied in communication, camouflage, and other fields.
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We designed a broadband lens along with a graphene/silicon photodiode for wide spectral imaging ranging from ultraviolet to near-infrared wavelengths. By using five spherical glass lenses, the broadband lens, with the modulation transfer function of 0.38 at 100â lp/mm, corrects aberrations ranging from 340 to 1700â nm. Our design also includes a broadband graphene/silicon Schottky photodiode with the highest responsivity of 0.63â A/W ranging from ultraviolet to near-infrared. By using the proposed broadband lens and the broadband graphene/silicon photodiode, several single-pixel imaging designs in ultraviolet, visible, and near-infrared wavelengths are demonstrated. Experimental results show the advantages of integrating the lens with the photodiode and the potential to realize broadband imaging with a single set of lens and a detector.
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Certain insecticides are known to have estrogenic effects by activating estrogen receptors through genomic transcription. This has led researchers to associate specific insecticide use with an increased breast cancer risk. However, it is unclear if estrogen receptor-dependent pathways are the only way in which these compounds induce carcinogenic effects. The objective of this study was to determine the impact of the pyrethroid insecticide permethrin on the growth of estrogen receptor negative breast cancer cells MDA-MB-231. Using tandem mass spectrometric techniques, the effect of permethrin on cellular protein expression was investigated, and gene ontology and pathway function enrichment analyses were performed on the deregulated proteins. Finally, molecular docking simulations of permethrin with the candidate target protein was performed and the functionality of the protein was confirmed through gene knockdown experiments. Our findings demonstrate that exposure to 10-40⯵M permethrin for 48â¯h enhanced cell proliferation and cell cycle progression in MDA-MB-231. We observed deregulated expression in 83 upregulated proteins and 34 downregulated proteins due to permethrin exposure. These deregulated proteins are primarily linked to transmembrane signaling and chemical carcinogenesis. Molecular docking simulations revealed that the overexpressed transmembrane signaling protein, G protein-coupled receptor 39 (GPR39), has the potential to bind to permethrin. Knockdown of GPR39 partially impeded permethrin-induced cellular proliferation and altered the expression of proliferation marker protein PCNA and cell cycle-associated protein cyclin D1 via the ERK1/2 signaling pathway. These findings offer novel evidence for permethrin as an environmental breast cancer risk factor, displaying its potential to impact breast cancer cell proliferation via an estrogen receptor-independent pathway.
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Proliferación Celular , Receptor alfa de Estrógeno , Insecticidas , Simulación del Acoplamiento Molecular , Permetrina , Receptores Acoplados a Proteínas G , Permetrina/toxicidad , Humanos , Proliferación Celular/efectos de los fármacos , Insecticidas/toxicidad , Línea Celular Tumoral , Receptor alfa de Estrógeno/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neoplasias de la Mama/patología , Femenino , Transducción de Señal/efectos de los fármacosRESUMEN
Metasurfaces have exhibited versatile capacities of controlling electromagnetic (EM) waves due to the high degree of freedom of designing artificially engineered meta-atoms. For circular polarization (CP), broadband phase gradient metasurfaces (PGMs) can be realized based on P-B geometric phase by rotating meta-atoms; while for linear polarization (LP), realization of broadband phase gradients has to resort to P-B geometric phase during polarization conversion and polarization purity has to be sacrificed for broadband properties. It is still challenging to obtain broadband PGMs for LP waves without polarization conversion. In this paper, we propose the design of 2D PGMs by combining the inherently wideband geometric phases and non-resonant phases of meta-atom, under the philosophy of suppressing Lorentz resonances that usually bring about abrupt phase changes. To this end, an anisotropic meta-atom is devised which can suppress abrupt Lorentz resonances in 2D for both x- and y-polarized waves. For y-polarized waves, the central straight wire is in perpendicular to electric vector Ein of incident waves, Lorentz resonance cannot be excited although the electrical length approaches or even exceeds half a wavelength. For x-polarized waves, the central straight wire is in parallel with Ein, a split gap is opened on the center of the straight wire so as to avoid Lorentz resonance. In this way, the abrupt Lorentz resonances are suppressed in 2D and the wideband geometric phase and the gradual non-resonant phase are left for broadband PGM design. As a proof of concept, a 2D PGM prototype for LP waves was designed, fabricated and measured in microwave regime. Both simulated and measured results show that the PGM can achieve broadband beam deflection for reflected waves for both x- and y-polarized waves in broadband, without changing the LP state. This work provides a broadband route to 2D PGMs for LP waves and can be readily extended to higher frequencies such as terahertz and infrared regimes.
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Half-wave wall is the most common method of achieving electromagnetic (EM) transparency. Transmission windows can be formed when reflected waves are out of phase. Due to the interference mechanism, these windows are dependent on the frequency and incident angle of EM waves, leading to limited bandwidth, especially under extreme angles. In this letter, we propose to extend the bandwidth of the transmission window under extreme angles by utilizing dispersion. To this end, long metallic wires are embedded into the half-wave wall matrix, without increasing the physical thickness. Due to the plasma-like behavior of metallic wires under TE-polarization, the effective permittivity of the half-wave wall, rather than keeping constant, increases with frequency nonlinearly. Such a dispersion will boost wideband transparency in two aspects. On one hand, an additional transmission window will be generated where the effective permittivity equals that of the air; on the other hand, the 1st- and 2nd-order half-wave windows will be made quite closer. By tailoring the dispersion, the three windows can be merged to enable wideband transparency under extreme incident angles. A proof-of-principle prototype was designed, fabricated, and measured to verify this strategy. Both simulated and measured results show that the prototype can operate in the whole Ku-band under incident angle [70°, 85°] for TE-polarized waves. This work provides an effective method of achieving wideband EM transparency under extreme angles and may find applications in radar, communications, and others.
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BACKGROUND: Atrial fibrillation (AF) and heart failure (HF) frequently coexist because of their similar pathological basis. However, whether sodium-glucose cotransporter 2 inhibitor (SGLT2i), a novel class of anti-HF medication, decreases the risk of AF in HF patients remains unclear. OBJECTIVES: The aim of this study was to assess the relationship between SGLT2i and AF in HF patients. METHODS: A meta-analysis of randomized controlled trails evaluating the effects of SGLT2i on AF in HF patients was performed. PubMed and ClinicalTrails.gov were searched for eligible studies until 27 November 2022. The risk of bias and quality of evidence were assessed through the Cochrane tool. Pooled risk ratio of AF for SGLT2i versus placebo in eligible studies was calculated. RESULTS: A total of 10 eligible RCTs examining 16,579 patients were included in the analysis. AF events occurred in 4.20% (348/8292) patients treated with SGLT2i, and in 4.57% (379/8287) patients treated with placebo. Meta-analysis showed that SGLT2i did not significantly reduce the risk of AF (RR 0.92; 95% CI 0.80-1.06; p = 0.23) in HF patients when compared to placebo. Similar results remained in the subgroup analyses, regardless of the type of SGLT2i, the type of HF, and the duration of follow-up. CONCLUSIONS: Current evidences showed that SGLT2i may have no preventive effects on the risk of AF in patients with HF. TRANSLATIONAL PERSPECTIVE: Despite HF being one of the most common heart diseases and conferring increased risk for AF, affective prevention of AF in HF patients is still unresolved. The present meta-analysis demonstrated that SGLT2i may have no preventive effects on reducing AF in patients with HF. How to effectively prevent and early detect the occurrence of AF is worth discussing.
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Fibrilación Atrial , Cardiopatías , Insuficiencia Cardíaca , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/epidemiología , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/prevención & control , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéuticoRESUMEN
Chronic itch is a complex sensation of the skin frequently associated with skin diseases, such as atopic dermatitis (AD) and psoriasis. Although Serpin E1 is implicated in chronic itch, its receptor and signaling pathways involved in itch are not known. In this study, the clinical relevance of a putative Serpin E1 receptor PLAUR to chronic itch, and the neuro-cutaneous Serpin E1-PLAUR signaling are explored. We found that PLAUR is overexpressed in skin specimens of human lesional AD and lesional psoriasis, and sensory neurons innervating MC903-induced AD-like murine skin. Murine PLAUR+ sensory neurons responded to Serpin E1, resulting in enrichment of numerous itch- and inflammation-related genes and their protein release. PLAUR resides in TLR2+ neurons and Serpin E1 stimulus led to transcriptional upregulation of TLR2 and its co-signaling proteins. Agonists of TLR2 propagated itch-related gene transcription including BNP, OSM, and PAR2. OSM induced acute itch in mice and promoted G-CSF and IL-8 release from human keratinocytes. Serpin E1 inhibitor reduced MC903-induced itch, epidermal hyperplasia, immunocyte infiltration, and resulted in lower transcription/expression levels of Serpin E1 and OSM. Taken together, the PLAUR-TLR2-OSM signaling promotes skin-nerve communication, cutaneous inflammation, and itch, all feeding into an aggravation of AD and exaggerated itch circuits.
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Prurito , Receptores del Activador de Plasminógeno Tipo Uroquinasa , Animales , Dermatitis Atópica/genética , Inflamación , Ratones , Inhibidor 1 de Activador Plasminogénico/genética , Prurito/genética , Psoriasis/genética , Receptores del Activador de Plasminógeno Tipo Uroquinasa/genética , Piel/metabolismo , Receptor Toll-Like 2/genéticaRESUMEN
Atopic dermatitis (AD) is a chronic skin disease, which is associated with intense itch, skin barrier dysfunction and eczematous lesions. Aberrant IL-20 expression has been implicated in numerous inflammatory diseases, including psoriasis. However, the role of IL-20 in AD remains unknown. Here, RNA-seq, Q-PCR, and immunocytochemistry were utilized to examine disease-driven changes of IL-20 and its cognate receptor subunits in skin from healthy human subjects, AD patients and murine AD-models. Calcium imaging, knockdown and cytokine array were used to investigate IL-20-evoked responses in keratinocytes and sensory neurons. The murine cheek model and behavioral scoring were employed to evaluate IL-20-elicited sensations in vivo. We found that transcripts and protein of IL-20 were upregulated in skin from human AD and murine AD-like models. Topical MC903 treatment in mice ear enhanced IL-20R1 expression in the trigeminal sensory ganglia, suggesting a lesion-associated and epidermal-driven mechanism for sensitization of sensory IL-20 signaling. IL-20 triggered calcium influx in both keratinocytes and sensory neurons, and promoted their AD-related molecule release and transcription of itch-related genes. In sensory neurons, IL-20 application increased TLR2 transcripts, implicating a link between innate immune response and IL-20. In a murine cheek model of acute itch, intradermal injection IL-20 and IL-13 elicited significant itch-like behavior, though only when co-injected. Our findings provide novel insights into IL-20 function in peripheral (skin-derived) itch and clinically relevant intercellular neuron-epidermal communication, highlighting a role of IL-20 signaling in the pathophysiology of AD, thus forming a new basis for the development of a novel antipruritic strategy via interrupting IL-20 epidermal pathways.
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Dermatitis Atópica , Animales , Calcio/metabolismo , Dermatitis Atópica/metabolismo , Humanos , Inflamación , Interleucinas , Ratones , Prurito/metabolismo , SensaciónRESUMEN
Two-dimensional (2D) materials are excellent candidates for advanced flexible electronics and gas sensors. Herein, we systematically investigate the layer-dependent electronic structures, mechanical properties and gas sensing characteristics of the newly synthesized γ-SnSe based on first-principles calculations. Bulk γ-SnSe is a typical van der Waals layered material with an indirect narrow band gap, while monolayer and multilayer γ-SnSe can be obtained through mechanical exfoliation due to its low cleavage energy. The band gap of γ-SnSe gradually increases with decreasing layers, reaching a value of 2.25 eV for the monolayer due to weakened interlayer coupling. Mechanical analysis reveals strong anisotropy in multilayer γ-SnSe, whereas the monolayer exhibits a negative Poisson's ratio (-0.023/-0.025). Additionally, based on the analysis of electronic structures, adsorption energies and charge transfer of the host materials after adsorption of various gases, it is found that the γ-SnSe monolayer demonstrates enhanced sensitivity and selectivity towards NO, NO2, and SO2 compared to CO, CO2, H2S and NH3. These findings highlight the potential of γ-SnSe as an excellent gas-sensitive material for the detection of nitrogen oxides and sulfur dioxide.
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Dissolved gas analysis is a strong tool for online health monitoring of electrical power equipment. The industry's large-scale deployment of photoacoustic (PA) sensors is still constrained by cost and sensitivity, despite the great accuracy achieved with a mid-infrared light source or optical sensors. We provide a low-cost PA sensor for ppb-level trace gas sensing based on a near-infrared distributed feedback laser source, miniature gas cell, and multiple microelectromechanical system (MEMS) microphones. Five multi-MEMS-microphones schemes are modeled. The simulation indicates that the sensor, including two MEMS microphones in the center of the resonator, is the most cost-efficient option. The experiments that present this scheme can be realized easily by modifying a traditional single microphone PA cell and with ppb-level sensitivity.
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Skeletal muscle is the most abundant tissue in mammals, and myogenesis and differentiation require a series of regulatory factors such as microRNAs (miRNAs). In this study, we found that miR-103-3p was highly expressed in the skeletal muscle of mice, and the effects of miR-103-3p on skeletal muscle development were explored using myoblast C2C12 cells as a model. The results showed that miR-103-3p could significantly reduce myotube formation and restrain the differentiation of C2C12 cells. Additionally, miR-103-3p obviously prevented the production of autolysosomes and inhibited the autophagy of C2C12 cells. Moreover, bioinformatics prediction and dual-luciferase reporter assays confirmed that miR-103-3p could directly target the microtubule-associated protein 4 (MAP4) gene. The effects of MAP4 on the differentiation and autophagy of myoblasts were then elucidated. MAP4 promoted both the differentiation and autophagy of C2C12 cells, which was contrary to the role of miR-103-3p. Further research revealed that MAP4 colocalized with LC3 in C2C12 cell cytoplasm, and the immunoprecipitation assay showed that MAP4 interacted with autophagy marker LC3 to regulate the autophagy of C2C12 cells. Overall, these results indicated that miR-103-3p regulated the differentiation and autophagy of myoblasts by targeting MAP4. These findings enrich the understanding of the regulatory network of miRNAs involved in the myogenesis of skeletal muscle.
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Diferenciación Celular , MicroARNs , Proteínas Asociadas a Microtúbulos , Mioblastos , Animales , Ratones , Diferenciación Celular/genética , Línea Celular , Proliferación Celular/genética , MicroARNs/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Desarrollo de Músculos , Mioblastos/citologíaRESUMEN
The trafficking of transient receptor potential (TRP) channels to the plasma membrane and the release of calcitonin gene-related peptide (CGRP) from trigeminal ganglion neurons (TGNs) are implicated in some aspects of chronic migraines. These exocytotic processes are inhibited by cleavage of SNAREs with botulinum neurotoxins (BoNTs); moreover, type A toxin (/A) clinically reduces the frequency and severity of migraine attacks but not in all patients for unknown reasons. Herein, neonatal rat TGNs were stimulated with allyl isothiocyanate (AITC), a TRPA1 agonist, and dose relationships were established to link the resultant exocytosis of CGRP with Ca2+ influx. The CGRP release, quantified by ELISA, was best fit by a two-site model (EC50 of 6 and 93 µM) that correlates with elevations in intracellular Ca2+ [Ca2+]i revealed by time-lapse confocal microscopy of fluo-4-acetoxymethyl ester (Fluo-4 AM) loaded cells. These signals were all blocked by two TRPA1 antagonists, HC-030031 and A967079. At low [AITC], [Ca2+]i was limited because of desensitisation to the agonist but rose for concentrations > 0.1 mM due to a deduced non-desensitising second phase of Ca2+ influx. A recombinant BoNT chimera (/DA), which cleaves VAMP1/2/3, inhibited AITC-elicited CGRP release to a greater extent than SNAP-25-cleaving BoNT/A. /DA also proved more efficacious against CGRP efflux evoked by a TRPV1 agonist, capsaicin. Nerve growth factor (NGF), a pain-inducing sensitiser of TGNs, enhanced the CGRP exocytosis induced by low [AITC] only. Both toxins blocked NGF-induced neuropeptide secretion and its enhancement of the response to AITC. In conclusion, NGF sensitisation of sensory neurons involves TRPA1, elevated Ca2+ influx, and CGRP exocytosis, mediated by VAMP1/2/3 and SNAP-25 which can be attenuated by the BoNTs.
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Toxinas Botulínicas , Canales de Potencial de Receptor Transitorio , Ratas , Animales , Péptido Relacionado con Gen de Calcitonina/farmacología , Péptido Relacionado con Gen de Calcitonina/metabolismo , Proteína 1 de Membrana Asociada a Vesículas/metabolismo , Factor de Crecimiento Nervioso/farmacología , Factor de Crecimiento Nervioso/metabolismo , Toxinas Botulínicas/metabolismo , Células Receptoras Sensoriales/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Canal Catiónico TRPA1/metabolismoRESUMEN
A hybrid design method for broadband radar cross section (RCS) reduction is proposed and successfully demonstrated based on the coupling effects between diffuse and absorptive structures. The reflection energy is distributed into more directions away from the source direction by the one-bit diffuse coding metasurface (CM). The two-layer resistive frequency selective surface (RFSS) is employed in the one-bit CM structure, reducing the amplitude of the co- and cross-polarized reflected waves under circularly polarized wave incidence by converting it into ohmic loss. In addition, the bandwidth of RCS reduction is further broadened through the coupling effects between the metallic patterns and the two-layer RFSS. The coupling effect shows that the absorption rate of the composite structure is significantly improved compared to the only RFSS structure. A lightweight CM loaded with RFSS (the area density is 597â g/m2) was fabricated, analyzed, simulated, and measured. The results show that the proposed mechanism can effectively break the bandwidth constraints of traditional diffusion and absorption methods. Furthermore, the proposed mechanism significantly expands the bandwidth of RCS reduction. The proposed metasurface can achieve a 10â dB RCS reduction in an ultra-wideband from 7.3 to 44.2â GHz with about 143.3% fractional bandwidth. Moreover, the metasurface also has good performances under wide-angle oblique incidences. Under the condition of maintaining lightweight, the design provides an idea for broadening the frequency band.
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Materials with both excellent frequency selective characteristic and ultralight mechanical properties are highly urgent demanded for its potential applications such as absorbing materials, artificial magnetic conductors, antenna and so on. However, although the research about materials with only excellent frequency selective characteristic or ultralight mechanical properties is advanced, in most cases, it is still a challenge that making a material possesses excellent frequency selective characteristic and ultralight mechanical properties simultaneously. So how to make the two properties achieving a high level simultaneously is a hot topic which remains to be solved. Herein, we proposed a novel and feasible strategy for achieving simultaneously excellent frequency selective characteristic and ultralight mechanical properties material. According to our strategy, the composite we designed behaviors as a FSS which can realize highly efficiency stop bands in 16.09-16.4GHz and 17.11-17.36GHz. At the same time, the composite can be regarded as an ultralight mechanical metamaterial. The relativity density of the composite can reduce to 431.99 Kg/m3, which have a distinct advantage compared with the dielectric layers that conversional FSS used. Moreover, Its elasticity modulus can reach 112.25 MPa and its bending stiffness can reach 90.54 N/mm. These performances show that although the density of the composite is reduced, the composite can still keep well mechanical properties. The strategy we proposed gives a good solution to the problem existing in the materials which desire both excellent frequency selective characteristic and ultralight mechanical properties. The composite is a designing example which can be applied in engineering. So the strategy is a guideline for researchers to achieve composite which owns both excellent frequency selective characteristic and ultralight mechanical properties.
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With the rapid development of wireless technology, the revolution of tailoring transmission window in dynamic way for the next generation communication systems is urgently required. However, the degree-of-freedom for switching transmission spectra of an effective medium still needs further investigation. Here, we propose a paradigm of solving this difficult academic issue via the method of bias-voltage-driven. Leveraging PIN diodes and varactor diodes into the predesigned positions of plasmonic meta-structures, the macro-control of transmission windows switch and the detailed dispersion manipulation can be separately achieved by synergy modulation of feed networks. Both the numerical simulations and experimental verifications are conducted to support the effectiveness of the proposed method. Significantly, the proposed paradigm presents great potential for applications in intelligent radome, adaptive communication systems, and other EM scenarios with multi-degree-of-freedom.
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The transmission of electromagnetic (EM) waves through a dielectric plate will be decreased significantly when the incident angle becomes extremely large, regardless of transverse electric (TE)- or transverse magnetic (TM)- polarization. In this regard, we propose a facile way of tailoring the permittivity of the dielectric material using metasurface to enhance the transmissions of both TE- and TM-polarized waves under extremely large incidence angles. Due to parallel or antiparallel electric fields induced by the metasurface, the net electric susceptibility is altered, and hence the effective permittivity can be tailored to improve the impedance matching on the two air-dielectric interfaces, which enhances the wave transmissions significantly under extreme incident angles. As an example, we apply this method to a typical ceramic-matrix composite (CMC) plate. By incorporating orthogonal meta-gratings into the CMC plate, its effective permittivity is reduced for the TE-polarized waves but increased for the TM-polarized waves under the extreme incidence angle, which can reduce the impedance for the TE-polarization and increase the Brewster angle for the TM-polarization. Therefore, the impedance matchings for both TE- and TM-polarizations are improved simultaneously and dual-polarized transmission enhancements are achieved under the extreme angles. Here, the transmission responses have been numerically and investigated using the finite-difference-time-domain (FDTD) method. A proof-of-principle prototype is designed, fabricated, and measured to verify this method. Both numerical simulations and measurement results show that the prototype can operate under extremely large incidence angles θi∈[75°,85°] with significant transmission enhancement for both TE- and TM-polarizations compared to the pure dielectric plate. This work provides a facile way to enhance the transmissions under extreme angles and can be readily extended to terahertz and optical frequencies.
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In many practical applications, dielectric electromagnetic (EM) windows are usually under large-angle incidence of EM waves rather than normal incidence. To guarantee normal operation of devices inside, high transmission must be maintained under large incident angles, especially for TE-polarized waves. In this work, we propose a method of achieving broadband transmission of TE-polarized waves under large incident angles by embedding meta-atoms within dielectric plates. To this end, long metallic wires and S-shaped structures are embedded in the original dielectric plate, the former of which will dilute the effective permittivity due to plasma oscillation and the latter will increase the effective permeability due to induced strong current loops under large incident angles. In this way, two consecutive transmission peaks can be generated, forming a broad transmission band under large incident angles. A proof-of-principle Ku-band prototype was designed, fabricated, and measured to verify this strategy. Both simulated and measured results show that the prototype can operate in the whole Ku-band under incident angle [60°, 85°] for TE-polarized waves, with significantly enhanced transmission. This work provides an effective method of enhancing large-angle transmission of EM waves and may find applications in radar, communications and others.
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The combination of metasurface and holographic technology is the most cutting-edge development, but most of the proposed designs are static and do not allow active changes through external stimulation after fabrication, which takes only a limited part of the advantage provided by metasurface. Here, we propose and demonstrate a switchable hybrid active metasurface hologram in the terahertz (THz) regime composed of dynamic pixels (VO2-CSRR) and static pixels (Au-CSRR) based on an intelligent algorithm, which can display some/all information in different temperature ranges. In particular, such performance shows excellent potential in the field of optical communication security, making it a promising candidate. To prove this possibility, we propose a scheme for optical information encryption/decryption and transmission, which takes metasurfaces as carriers of encrypted information and state/polarization/positions as the secret key components. Only when the two matches correctly can we get the hidden real information. The security of our proposed scheme has reached an unprecedented level, providing a new road for communication security.