Due to the harsh environment of high humidity and dust in tunnel construction, the vision measurement system needs to be equipped with an explosion-proof glass protective cover. The refractive effect ...of the plate glass window invalidates the pinhole model. This paper proposes a comprehensive solution for addressing the issue of plane refraction. First, the imaging model for non-parallel plane refraction is established based on dynamic virtual focal length and the Rodriguez formula. Further, due to the failure of the epipolar constraint principle in binocular vision systems caused by plane refraction, this paper proposes the epipolar constraint model for independent refractive plane imaging. Finally, an independent refraction plane triangulation model is proposed to address the issue of triangulation failure caused by plane refraction. The RMSE of the depth of field errors in the independent refraction plane triangulation model is 2.9902 mm before correction and 0.3187 mm after correction. The RMSE of the positioning errors before and after correction are 3.5661 mm and 0.3465 mm, respectively.
On-chip topological nanophotonic filtering and routing devices are important components of integrated nanophotonic chip. The device filters topological photonic states with multiple frequencies and ...routes them into different output ports, respectively. However, there is no effective method to implement such devices to date. Here, an on-chip topological five-channel filtering and routing device is realized for the first time. Topological edge states are constructed based on synthetic dimension, which can use dielectric materials to construct topological photonic states without external magnetic field. This method has advantages including simple structure, easy integration, and high signal-to-noise ratio. The implementation of on-chip topological multichannel filtering and routing device is of great significance to the development of topological nanophotonic devices.
The microstructure and mechanical properties of (Zr-Ti)1-χNiχ(χ =0, 1, 3, and 5 wt.%) alloys were studied. With the addition of nickel (Ni), the phase composition of alloys changes from α phase to α ...phase + hexagonal close packed (hcp) C14 Laves-phase. The thickness of lamellar α phase decreases with increasing Ni content. Optical microscopy and transmission electron microscopy results indicated that C14 Laves-phase is formed on the boundary. The Zr-Ti-3wt.%Ni alloys exhibits better ultimate compressive strength and compressive plasticity (1715 MPa and 9.70%) than that of Zr-Ti alloys (1598 MPa and 12.40%). The decrease of the average thickness of the lamellar α-phases (from 0.183 μm to 0.065 μm) leads to the improvement of the strength of the alloy. Additionally, the solid solution strengthening and the second phase strengthening are also important reasons for the improvement of the strength.
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•The effect of Ni addition on the microstructural of Zr-Ti alloys is studied.•The mechanism of microstructural evolution is discussed.•C14 Laves-phase is formed on the grain boundary.•Strength mechanism is proposed from different aspects.
We propose an all-dielectric nanorod array for ultra-sensitive refractive index sensing based on quasi-bound states in the continuum (BICs). The nanorod is fabricated by silicon or silicon with an ...air hole, i.e., the hollow silicon nanorod. The quasi-BICs are formed in the hollow silicon nanorod array due to the symmetry-breaking of air holes. The high-quality factor (Q-factor) and ultra-narrow reflectance spectral width at quasi-BICs contribute to high performances of the sensor. The numerical results show that the sensitivity and figure of merit (FOM) can reach up to 602.9 nm/RIU and 34,977, respectively. The results indicate that the proposed nanostructures of quasi-BICs are promising for advanced biosensing applications.
Tropical cyclones (TCs) seriously threaten the safety of human life and property especially when approaching a coast or making landfall. Robust, long-lead predictions are valuable for managing policy ...responses. However, despite decades of efforts, seasonal prediction of TCs remains a challenge. Here, we introduce a deep-learning prediction model to make skillful seasonal prediction of TC track density in the Western North Pacific (WNP) during the typhoon season, with a lead time of up to four months. To overcome the limited availability of observational data, we use TC tracks from CMIP5 and CMIP6 climate models as the training data, followed by a transfer-learning method to train a fully convolutional neural network named SeaUnet. Through the deep-learning process (i.e., heat map analysis), SeaUnet identifies physically based precursors. We show that SeaUnet has a good performance for typhoon distribution, outperforming state-of-the-art dynamic systems. The success of SeaUnet indicates its potential for operational use.
A controllable, general, and simple alkaline etching strategy was used to synthesize deformable hollow mesoporous organosilica nanocapsules (DMONs), in which multiple organic moieties were ...homogeneously incorporated into the framework.
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Deformable materials have garnered widespread attention in biomedical applications. Herein, a controllable, general, and simple alkaline etching strategy was used to synthesize deformable hollow mesoporous organosilica nanocapsules (DMONs), in which multiple organic moieties were homogeneously incorporated into the framework. DMONs with double-, triple-, and even quadruple-hybridized frameworks were prepared by the selective introduction of organosilica precursors in accordance with the chemical homology principle through a surfactant-directed sol–gel procedure and a subsequent etching process in alkaline solution. The triple-hybridized DMONs possessed uniform and controllable diameters (100–330 nm), and large hollow cavities (50–270 nm). Liquid cell electron microscopy images demonstrated that the DMONs were deformable in solution. Elemental mapping images suggested that the organic components were homogeneous distribution within the entire DMONs framework. Statistical analysis of cell proliferation assays showed that breast cancer MCF-7 viability exceeded 85% when the cells are incubated with the triple-hybridized DMONs (800 μg mL−1) for 24 h. Histological assessments of main organs indicated no tissue injury or necrosis after intravenous injection of the DMONs 7 days (5 mg kg−1 body weight). Quantitative analysis indicated that the cellular uptake of the DMONs was 6-fold higher than that of their hard counterparts when the number of nanoparticles added was 1.25 × 104, and similar results were found for 4 T1 cells. Furthermore, doxorubicin (DOX) loaded triple-hybridized DMONs with a loading efficiency of 16.9 wt%, produced a strong killing effect on tumor cells. Overall, DMONs with various incorporated organic functional groups could serve as novel nanoplatforms for drug delivery in biomedical applications.
O-GlcNAcylation is a reversible post-translational modification involved in the regulation of cytosolic, nuclear, and mitochondrial proteins. Only two enzymes, OGT (O-GlcNAc transferase) and OGA ...(O-GlcNAcase), control the attachment and removal of O-GlcNAc on proteins, respectively. Whereas a variant OGT (mOGT) has been proposed as the main isoform that O-GlcNAcylates proteins in mitochondria, identification of a mitochondrial OGA has not been performed yet. Two splice variants of OGA (short and long isoforms) have been described previously. In this work, using cell fractionation experiments, we show that short-OGA is preferentially recovered in mitochondria-enriched fractions from HEK-293T cells and RAW 264.7 cells, as well as mouse embryonic fibroblasts. Moreover, fluorescent microscopy imaging confirmed that GFP-tagged short-OGA is addressed to mitochondria. In addition, using a Bioluminescence Resonance Energy Transfer (BRET)-based mitochondrial O-GlcNAcylation biosensor, we show that co-transfection of short-OGA markedly reduced O-GlcNAcylation of the biosensor, whereas long-OGA had no significant effect. Finally, using genetically encoded or chemical fluorescent mitochondrial probes, we show that short-OGA overexpression increases mitochondrial ROS levels, whereas long-OGA has no significant effect. Together, our work reveals that the short-OGA isoform is targeted to the mitochondria where it regulates ROS homoeostasis.
This paper examines the effects of temperature and humidity on the absorption spectrum and concentration of nitrous oxide (N2O) using a compact, portable open optical-path gas detection sensor ...system. We obtained the absorption coefficient and widened the linear function of the N2O absorption spectrum related to temperature by theoretical analysis and the high-resolution transmission molecular absorption database (HITRAN). Afterward, we conducted real-time monitoring of N2O in both campus and laboratory environments using lasers for a duration of 32 h and 6 h, respectively, and the results were compared and analyzed with the theoretical derivation. The results show that the concentration of N2O increased with increasing environmental temperature but decreased with increasing humidity. Furthermore, the variations in temperature and humidity significantly affected the peak values of the second-harmonic (2f) and first-harmonic (1f) signals. Finally, the temperature N2O concentration and humidity N2O curves were calibrated separately, and temperature changes were positively correlated with the N2O concentration, while humidity changes were negatively correlated with the N2O concentration. The experimental results indicate that the concentration of N2O and its absorption spectra are influenced by humidity and temperature, which has a significant reference value in the absorption and measurement of N2O in practical applications.
Despite numerous studies, the impact of global warming on the tropical cyclone (TC) track and intensity by reasons of data inhomogeneity in remote sensing and large natural variability over a ...relatively short period of observation is still controversial. Three carbon-emission sensitivity experiments are conducted to investigate how TC track and intensity respond to changes in the oceanic and atmospheric environment under global warming. The results show a high sensitivity of the simulated TC track and intensity to global warming. On one hand, with increase in carbon emissions, the western Pacific subtropical high expands notably, increasing the poleward steering flow and eventually leading to a poleward shift of TC. On the other hand, the underlying sea-surface temperature and surface-entropy flux increase and, thus, favor the convections near the eyewall. Moreover, the TC structure becomes more upright, which is closely related to the larger pressure gradient near the eyewall. As a result, TC intensity increases with carbon emissions. However, this increase is notably smaller than the maximum potential intensity theory as the TC intensity can reach a threshold if carbon emission still increases in the future. The involved mechanisms on the changes of TC track and intensity are also revealed.
Recently, Co–Cr–Ni medium-entropy alloys (MEAs) have garnered significant attention in the materials field owing to exceptional properties. However, the various mechanisms of transformation induced ...plasticity (TRIP) and twinning induced plasticity (TWIP) effects with variation of chemical compositions, strain rates, temperature and grain size in polycrystalline Co–Cr–Ni MEAs remains challenging. By utilizing molecular dynamics simulations, the uniaxial tensile deformation of polycrystalline Co–Cr–Ni MEAs, including equiatomic CoCrNi, and non-equiatomic Co10(CrNi)90, Cr10(CoNi)90 and Ni10(CoCr)90, has been investigated. The influence of strain rates and deformation temperatures on the mechanical properties and deformation mechanisms of CoCrNi MEA has also been explored under uniaxial tensile loading. Further, dislocation multiplication, slip motion, microstructure evolution, and their interplay with tensile deformation under different conditions have also been studied. Additionally, the relationship between different grain sizes and the flow stress of polycrystalline CoCrNi MEA has also been discussed. The findings reveal that Co10(CrNi)90 MEA exhibits highest yield stress, Young's modulus, and flow stress. While CoCrNi MEA and Cr10(CoNi)90 MEA with equiatomic ratios display similar mechanical properties, Ni10(CoCr)90 MEA demonstrates superior ductility owing to the strong TWIP and TRIP effects. Besides, strain rate, deformation temperature, and grain size all have significant impacts on the deformation mechanisms of polycrystalline CoCrNi MEA.