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In mammals, sperm-borne regulators can be transferred to oocytes during fertilization and have different effects on the formation of pronuclei, the first cleavage of zygotes, the development of preimplantation embryos and even the metabolism of individuals after birth. The regulatory role of sperm microRNAs (miRNAs) in the development of bovine preimplantation embryos has not been reported in detail. By constructing and screening miRNA expression libraries, we found that miR-202 was highly enriched in bovine sperm. As a target gene of miR-202, co-injection of SEPT7 siRNA can partially reverse the accelerated first cleavage of bovine embryos caused by miR-202 inhibitor. In addition, both a miR-202 mimic and SEPT7 siRNA delayed the first cleavage of somatic cell nuclear transfer (SCNT) embryos, suggesting that miR-202-SEPT7 mediates the delay of first cleavage of bovine embryos. By further exploring the relationship between miR-202/SEPT7, HDAC6 and acetylated α-tubulin during embryonic development, we investigated how sperm-borne miR-202 regulates the first cleavage process of bovine embryos by SEPT7 and demonstrate the potential of sperm-borne miRNAs to improve the efficiency of SCNT.
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Citoesqueleto/metabolismo , Embrião de Mamíferos/metabolismo , MicroRNAs/metabolismo , Septinas/metabolismo , Regiões 3' não Traduzidas , Acetilação , Animais , Antagomirs/metabolismo , Bovinos , Desenvolvimento Embrionário , Feminino , Fertilização in vitro , Desacetilase 6 de Histona/metabolismo , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Gravidez , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Septinas/antagonistas & inibidores , Septinas/genética , Espermatozoides/metabolismo , Tubulina (Proteína)/metabolismo , Zigoto/metabolismoRESUMO
The low energy efficiency and limited cycling life of rechargeable Zn-air batteries (ZABs) arising from the sluggish oxygen reduction/evolution reactions (ORR/OERs) severely hinder their commercial deployment. Herein, a zeolitic imidazolate framework (ZIF)-derived strategy associated with subsequent thermal fixing treatment is proposed to fabricate dual-atom CoFeâNâC nanorods (Co1 Fe1 âNâC NRs) containing atomically dispersed bimetallic Co/Fe sites, which can promote the energy efficiency and cyclability of ZABs simultaneously by introducing the low-potential oxidation redox reactions. Compared to the mono-metallic nanorods, Co1 Fe1 âNâC NRs exhibit remarkable ORR performance including a positive half-wave potential of 0.933 V versus reversible hydrogen electrode (RHE) in alkaline electrolyte. Surprisingly, after introducing the potassium iodide (KI) additive, the oxidation overpotential of Co1 Fe1 âNâC NRs to reach 10 mA cm-2 can be significantly reduced by 395 mV compared to the conventional destructive OER. Theoretical calculations show that the markedly decreased overpotential of iodide oxidation can be ascribed to the synergistic effects of neighboring CoâFe diatomic sites as the unique adsorption sites. Overall, aqueous ZABs assembled with Co1 Fe1 âNâC NRs and KI as the air-cathode catalyst and electrolyte additive, respectively, can deliver a low charging voltage of 1.76 V and ultralong cycling stability of over 230 h with a high energy efficiency of ≈68%.
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It is challenging yet promising to design highly accessible N-doped carbon skeletons to fully expose the active sites inside single-atom catalysts. Herein, mesoporous N-doped carbon hollow spheres with regulatable through-pore size can be formulated by a simple sequential synthesis procedure, in which the condensed SiO2 is acted as removable dual-templates to produce both hollow interiors and through-pores, meanwhile, the co-condensed polydopamine shell is served as N-doped carbon precursor. After that, FeâNâC hollow spheres (HSs) with highly accessible active sites can be obtained after rationally implanting Fe single-atoms. Microstructural analysis and X-ray absorption fine structure analysis reveal that high-density FeâN4 active sites together with tiny Fe clusters are uniformly distributed on the mesoporous carbon skeleton with abundant through-pores. Benefitted from the highly accessible FeâN4 active sites arising from the unique through-pore architecture, the FeâNâC HSs demonstrate excellent oxygen reduction reaction (ORR) performance in alkaline media with a half-wave potential up to 0.90 V versus RHE and remarkable stability, both exceeding the commercial Pt/C. When employing FeâNâC HSs as the air-cathode catalysts, the assembled Zn-air batteries deliver a high peak power density of 204 mW cm-2 and stable discharging voltage plateau over 140 h.
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A novel approach-integrating a simulated annealing (SA) algorithm with deep learning (DL) acceleration-is presented for the rapid and accurate development of terahertz perfect absorbers through forward prediction and backward design. The forward neural network (FNN) effectively deduces the absorption spectrum based on metasurface geometry, resulting in an 80,000-fold increase in computational speed compared to a full-wave solver. Furthermore, the absorber's structure can be precisely and promptly derived from the desired response. The incorporation of the SA algorithm significantly enhances design efficiency. We successfully designed low-frequency, high-frequency, and broadband absorbers spanning the 4 to 16â THz range with an error margin below 0.02 and a remarkably short design time of only 10â min. Additionally, the proposed model in this Letter introduces a novel, to our knowledge, method for metasurface design at terahertz frequencies such as the design of metamaterials across optical, thermal, and mechanical domains.
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A facile strategy is proposed for a high-performance electro-optic modulator with an etchless lithium niobate (LN) layer assisted by the silicon resonator metasurface, which pioneers the way to engineer an ultra-sharp spectral line shape via the excitation of quasi-bound states in the continuum (BICs). Meanwhile, strong out-of-plane electric/magnetic fields within the proximity area to the electro-optic layer lead to ultra-sensitive modulations. As a result, only a slight voltage change of 0.2â V is needed to fully shift the resonances and then realize switching modulation between the "off" and "on" states. The findings pave new, to the best of our knowledge, insights in reconfiguration of spatial optical fields and offer prospects for functional optoelectronic devices.
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Near-unity circular dichroism (CD) with high quality (Q)-factors has wide applications in chiral lasers, modulators, detectors, etc. In this work, we firstly suggest a feasible approach to realize near-unity CD (â¼0.94) with a high Q-factor (>2 × 104) supported by a toroidal dipole (TD) empowered superchiral quasi-bound states in the continuum (BICs) metasurface. Based on intensity, excellent electrical switching is achieved by adjusting the Fermi energy of the graphene on the metasurface. High refractive index sensitivity (136.2â nm/RIU) and figure of merit (1135â RIU-1) demonstrate its superior chiral sensing detection performance. Moreover, the near-unity CD displays a large robustness to the asymmetry offset. Our work paves a feasible avenue for well-designed superchiral quasi-BIC metasurfaces with high Q-factor near-unity CD for chiral applications in electrically tunable modulators, switches, sensors, etc.
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Herein, we propose and demonstrate an efficient light modulator by intercalating the nonlinear thin film into the optical resonator cavities, which introduce the ultra-sharp resonances and simultaneously lead to the spatially overlapped optical field between the nonlinear material and the resonators. Differential field intensity distributions in the geometrical perturbation-assisted optical resonator make the high quality-factor resonant modes and strong field confinement. Multiple channel light modulation is achieved in such layered system, which enables the capability for tunability-selective modulation. The maximal modulation tunability is up to 1.968â nm/V, and the figure of merit (FOM) reaches 65.6â V-1, showing orders of magnitude larger than that of the previous state-of-the-art modulators. The electrical switch voltage is down to 0.015â V, the maximal switching ratio is 833%, and the extinction ratio is also up to 9.70â dB. These features confirm the realization of high-performance modulation and hold potential for applications in switches, communication and information, augmented and virtual reality, etc.
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Chiral metasurfaces hold excellent performance in enhancing spin-dependent light-matter interaction, showing broad application prospects in areas such as chiral imaging, chiral light sources, and chiral sensing. However, utilizing resonant metasurfaces to achieve all-optical logic gates has not been reported yet. In this work, dual-channel intrinsic and nonlinear chiroptical responses are achieved on lithium niobate metasurfaces. The combination of bound states in the continuum (BICs) resonant modes with chiral metasurfaces has revealed its linear and nonlinear chirality. The metasurface achieves linear circular dichroism above 0.9 and nonlinear circular dichroism close to 0.9 on the dual-band. Based on the second-order nonlinear chiroptical response, multiple all-optical logic gates (including NOT, OR, NAND, AND, and NOR) can be realized on the chiral metasurfaces. Our results confirm the operability of resonant metasurfaces in realizing all-optical logic gates, offering a potentially promising approach for the development of new, to the best of our knowledge, all-optical logic devices.
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We achieve dynamically tunable dual quasi-bound states in the continuum (quasi-BICs) by implementing them in a silicon-graphene multilayer composite structure and utilize the quasi-BIC modes to achieve ultra-large group delays (velocity of light slows down 105 times), showing 2-3 orders of magnitude higher than the group delays of previous electromagnetically induced transparency modes. The double-layer graphene holds great tuning capability and leads to the dramatically reduced group delay from 1929.82 to 1.58â ps with only 100â meV. In addition, the log-linear variation rule of group delay with Fermi level (Ef) in the range of 0-10â meV is analyzed in detail, and the double-logarithmic function relationship between the group delay and quality factor (Q-factor) is theoretically verified. Finally, the quantitative modulation of the optical storage is further realized in this basis. Our research provides ideas for the reform and upgrading of slow optical devices.
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We realize the observation of near-unity nonreciprocal polarized transmission via the bound states in the continuum (BICs) in a double-layer grating structure. By introducing out-of-plane perturbations and topological defects that break the mirror symmetry between the upper and lower layers, the far-field polarization states in momentum space are inverted vertically and horizontally, showing mirrored polarization characteristics for incident channels from different upper and lower ports. During the process of introducing mirror perturbations in the upper and lower layers, a π/2 phase inversion occurs in the Ð-M direction, making chirality possible. Utilizing this bidirectionally tunable nonreciprocal spatiotemporal phase transition enables multiple modulations of polarization states and opens up more possibilities for asymmetric light manipulation in chiral optical effects.
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Heterogeneous metamaterials containing excitonic materials provide an ideal platform for strong exciton-photon coupling. In this Letter, we theoretically demonstrate four strong couplings in a heterogeneous metamaterial consisting of a TiO2 grating standing on a perovskite-WS2-perovskite waveguide layer by tuning the structural sizes. The quasi-bound state in the continuum (qBIC) and the guided mode resonance (GMR) both strongly coupled with the excitons of both perovskite and WS2 under oblique incident illumination, resulting in four large Rabi splittings of 177.32, 187.53, 406.25, and 435.09â meV via a reasonable combination of oscillator strengths of perovskite and WS2. Double strong coupling behaviors are also achieved when the grating period equals 222â nm with an incident light angle of 19.3°. Moreover, double ultrastrong coupling can even be realized by the GMR and qBIC respectively interacting with the exciton of WS2 when its oscillator strength reaches a certain value. Our work paves an effective avenue to realizing strong coupling and even ultrastrong coupling between multiple excitons and multiple optical modes.
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Infertility is a condition characterized by a low fertility rate, which significantly affects the physical and mental health of women of reproductive age. Typically, the treatment duration is prolonged, and the therapeutic outcomes are often unsatisfactory. Professor Cheng-yao He, a renowned expert in traditional Chinese medicine, commonly uses the herb Cnidii Fructus (SCZ) for the treatment of infertility. However, the exact mechanism remains unclear, and there is limited research available on this topic. The active ingredients of SCZ were obtained from the traditional chinese medicine system pharmacology (TCMSP) database and screened for pharmacokinetics (PK), involving absorption, distribution, metabolism, and excretion (ADME). Target prediction was performed by SwissTargetPrediction database, and infertility-related disease targets were searched in GeneCards, TTD, DrugBank, and OMIM database. The protein-protein interaction (PPI) network was constructed using the STRING database (Version 11.5) and analyzed by Cytoscape software (Version 3.9.1). Additionally, the target genes were subjected to biological enrichment analysis in the Metascape database, including gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis, and the "Disease-Ingredient-pathway-target" network was constructed using Cytoscape software. With the assistance of AutoDockVina, Ligplot, and PyMOL software, a validation of Molecular docking results and a visualization of the results were performed. This study identified 11 retained active ingredients of SCZ, 447 drug targets, 233 of which were related to infertility, and 5393 disease targets. GO enrichment analysis mainly involved 221 biological processes such as cellular response to chemical stress and gland development. KEGG enrichment analysis mainly involved 68 pathways such as thyroid hormone signaling pathway, estrogen signaling pathway, FOXO signaling pathway, and PI3K/Akt signaling pathway. Molecular docking showed that the core active ingredients of SCZ, including Ammidin, Diosmetin, Xanthoxylin N, and Prangenidin, had strong binding abilities with core targets such as MDM2, MTOR, CCND1, EGFR, and AKT1. This study preliminarily demonstrated that SCZ may act on the PI3K/Akt signaling pathway, exerting its therapeutic effects on infertility by improving energy metabolism disorders and endometrial receptivity, inducing primordial follicle activation, regulating oocyte proliferation, differentiation, and apoptosis, and promoting the release of dominant follicles.
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BACKGROUND: Fecal microbiota transplantation (FMT) of healthy donors improves ulcerative colitis (UC) patients by restoring the balance of the gut microbiota. However, donors vary in microbial diversity and composition, often resulting in weak or even ineffective FMT. Improving the efficacy of FMT through combination treatment has become a promising strategy. Ulva lactuca polysaccharides (ULP) have been found to benefit host health by regulating gut microbiota. The effect of the combination of ULP and FMT in ameliorating UC has not yet been evaluated. RESULTS: The present study found that supplementation with ULP combined with FMT showed better effects in ameliorating UC than supplementation with FMT alone. Results suggested that FMT or ULP combined with FMT alleviated the symptoms of UC in mice, as evidenced by prevention of body weight loss, improvement of disease activity index and protection of the intestinal mucus. Notably, ULP in combination with FMT was more effective than FMT in reducing levels of cytokines and related inflammatory enzymes. In addition, ULP combined with FMT effectively restored the dysbiosis induced by dextran sulfate sodium (DSS) and further enriched probiotics (such as Bifidobacterium). The production of short-chain fatty acids, especially acetic acid, was also significantly enriched by ULP combined with FMT. CONCLUSION: Supplementation of ULP combined with FMT could significantly ameliorate DSS-induced colitis in mice by inhibiting inflammation and restoring dysbiosis of gut microbiota. These results suggested that ULP combined with FMT has potential application in ameliorating UC. © 2024 Society of Chemical Industry.
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Single-atom Fe-N-C (Fe1 -N-C) materials represent the benchmarked electrocatalysts for oxygen reduction reaction (ORR). However, single Fe atoms in the carbon skeletons cannot be fully utilized due to the mass transfer limitation, severely restricting their intrinsic ORR properties. Herein, a self-sacrificing template strategy is developed to fabricate ultrathin nanosheets assembled Fe1 -N-C hollow microspheres (denoted as Fe1 /N-HCMs) by rational carbonization of Fe3+ chelating polydopamine coated melamine cyanuric acid complex. The shell of Fe1 /N-HCMs is constructed by ultrathin nanosheets with thickness of only 2 nm, which is supposed to be an ideal platform to isolate and fully expose single metal atoms. Benefiting from unique hierarchical hollow architecture with highly open porous structure, 2 nm-thick ultrathin nanosheet subunits and abundant Fe-N4 O1 active sites revealed by X-ray absorption fine structure analysis, the Fe1 /N-HCMs exhibit high ORR performance with a positive half-wave potential of 0.88 V versus the reversible hydrogen electrode and robust stability. When served as air-cathode catalysts with ultralow loading mass of 0.25 mg cm-2 , Fe1 /N-HCMs based Zn-air batteries present a maximum power density of 187 mW cm-2 and discharge specific capacity of 806 mA h gZn -1 in primary Zn-air batteries, all exceeding those of commercial Pt/C.
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OBJECTIVE: The gut microbial composition has been linked to metabolic and autoimmune diseases, including arthritis. However, there is a dearth of knowledge on the gut bacteriome, mycobiome, and virome in patients with gouty arthritis (GA). METHODS: We conducted a comprehensive analysis of the multi-kingdom gut microbiome of 26 GA patients and 28 healthy controls, using whole-metagenome shotgun sequencing of their stool samples. RESULTS: Profound alterations were observed in the gut bacteriome, mycobiome, and virome of GA patients. We identified 1,117 differentially abundant bacterial species, 23 fungal species, and 4,115 viral operational taxonomic units (vOTUs). GA-enriched bacteria included Escherichia coli_D GENOME144544, Bifidobacterium infantis GENOME095938, Blautia_A wexlerae GENOME096067, and Klebsiella pneumoniae GENOME147598, while control-enriched bacteria comprised Faecalibacterium prausnitzii_G GENOME147678, Agathobacter rectalis GENOME143712, and Bacteroides_A plebeius_A GENOME239725. GA-enriched fungi included opportunistic pathogens like Cryptococcus neoformans GCA_011057565, Candida parapsilosis GCA_000182765, and Malassezia spp., while control-enriched fungi featured several Hortaea werneckii subclades and Aspergillus fumigatus GCA_000002655. GA-enriched vOTUs mainly attributed to Siphoviridae, Myoviridae, Podoviridae, and Microviridae, whereas control-enriched vOTUs spanned 13 families, including Siphoviridae, Myoviridae, Podoviridae, Quimbyviridae, Phycodnaviridae, and crAss-like. A co-abundance network revealed intricate interactions among these multi-kingdom signatures, signifying their collective influence on the disease. Furthermore, these microbial signatures demonstrated the potential to effectively discriminate between patients and controls, highlighting their diagnostic utility. CONCLUSIONS: This study yields crucial insights into the characteristics of the GA microbiota that may inform future mechanistic and therapeutic investigations.
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Artrite Gotosa , Microbioma Gastrointestinal , Microbiota , Micobioma , Humanos , População do Leste Asiático , Bactérias/genéticaRESUMO
In this work, a method for designing an ultra-narrowband absorber platform is presented with asymmetric silicon-based dimer-resonators grating. Within the infrared range of 3000 â¼ 4000â nm, two narrowband absorption peaks with absorptivity greater than 99% are produced by the absorber. Moreover, during the optical sensing, such an absorber platform shows high-performance sensitivity factors for the absorption wavelengths at λ1 = 3468â nm (S = 3193â nm/RIU, FOM = 532) and at λ2 = 3562â nm (S = 3120â nm/RIU, FOM = 390). Strong scattering coupling and the magnetic resonances supported in this silicon based grating produce the high absorption. Otherwise, additional methods such as the polarization and incident angles are used to further tune the absorption responses in the intensity and wavelengths, indicating the feasibility for artificial manipulations. The achieved ultra-sharp perfect absorption and the related sensitive response hold the silicon based resonant scheme with wide applications in bio-sensing, spectral filtering and other fields.
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Chiral metasurfaces with tunable or switchable circular dichroism (CD) responses hold great potential for advanced optical devices. In this work, we theoretically propose and numerically demonstrate a chiral metasurface absorber composed of periodically serrated Ge2Sb2Te5 (GST) resonators. By harnessing strong plasmonic resonance using the gradient geometry, we achieve a strongly enhanced chiral response with a CD value of 0.98 at λ2 = 2359â nm and a CD value of 0.7 at λ1 = 2274â nm. Additionally, by controlling the gradient difference in the serrated GST resonator, we can modify the CD intensity in multiple dimensions and near-perfectly optimize the chiral properties. Furthermore, it is worth noting that the CD value can be strongly varied by adjusting the phase transition characteristics of GST in the range of 0.007 to 0.7 at λ1 and 0.002 to 0.98 at λ2, corresponding to a switch between "on" and "off" states. The findings give new insight into multi-functional chiroptics and hold wide applications.
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Simplified thin-film structures with the capability of spatial and frequency-selective optical field coupling and absorption are desirable for nanophotonics. Herein, we demonstrate the configuration of a 200-nm-thick random metasurface formed by refractory metal nanoresonators, showing near-unity absorption (absorptivity > 90%) covering the visible and near-infrared range (0.380-1.167â µm). Importantly, the resonant optical field is observed to be concentrated in different spatial areas according to different frequencies, paving a feasible way to artificially manipulate spatial coupling and optical absorption via the spectral frequency. The methods and conclusions derived in this work are applicable throughout a wide energy range and hold applications for frequency-selective nanoscale optical field manipulation.
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We successfully achieved high-Q dual-band quasi-bound states in the continuum (BICs) by introducing geometrical perturbations and thermally induced material perturbations into silicon half-disk nanodimers. Importantly, it is found that the Q factor obtained from the thermally induced material perturbations fits better with the inverse quadratic function of the asymmetry relation than that of the geometrical-perturbations-based system. Notably, we demonstrated that changes occurring at the sub-K scale can enable the simultaneous realization of the full width at half maximum offset distance for quasi-BICs and a maximum contrast ratio exceeding 44â dB. Our research provides novel, to the best of our knowledge, insights for potential applications in nano-lasers, temperature sensors, and infrared imaging.
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Herein, a graphene-dielectric metasurface with the function of stably tunable and fast responding on the chiroptics is theoretically investigated and numerically demonstrated. Via utilizing the intrinsic thermo-optical effect of the silicon, the circular dichroism (CD) peak position can be linearly scaled with a spectral sensitivity of up to 0.06â nm/K by artificially adjusting the temperature. Moreover, a perfectly adjusting manipulation with a wavelength shift of full width at half maximum for the resonant spectrum and the simultaneously maintained CD values can be realized by a slight temperature variation of â¼0.8â K. Additionally, we take a graphene layer as the heating source to actually demonstrate the ultra-fast thermal generation. Applying an input voltage of 2â V to the graphene with only 10â µs can rapidly increase the metasurface temperature of up to 550â K. Such performances hold the platform with wide applications in functional chiroptics and optoelectronics.