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Highlights The SiO2 nanofiber membranes and MXene@c-MWCNT6:4 as one unit layer (SMC1) were bonded together with 5 wt% PVA solution. When the structural unit is increased to three layers, the resulting SMC3 has an average electromagnetic interference SET of 55.4 dB and a low thermal conductivity of 0.062 W m−1 K−1. SMCx exhibit stable electromagnetic interference shielding and excellent thermal insulation even in extreme heat and cold environment.

Abstract The intermitochondrial cement (IMC) and chromatoid body (CB) are posited as central sites for piRNA activity in mice, with MIWI initially assembling in the IMC for piRNA processing before translocating to the CB for functional deployment. The regulatory mechanism underpinning MIWI translocation, however, has remained elusive. We unveil that piRNA loading is the trigger for MIWI translocation from the IMC to CB. Mechanistically, piRNA loading facilitates MIWI release from the IMC by weakening its ties with the mitochondria-anchored TDRKH. This, in turn, enables arginine methylation of MIWI, augmenting its binding affinity for TDRD6 and ensuring its integration within the CB. Notably, loss of piRNA-loading ability causes MIWI entrapment in the IMC and its destabilization in male germ cells, leading to defective spermatogenesis and male infertility in mice. Collectively, our findings establish the critical role of piRNA loading in MIWI translocation during spermatogenesis, offering new insights into piRNA biology in mammals.

Black phosphorus (BP) has attracted extensive attention due to its unique optical and electrical properties. However, BP is easily oxidized in the air, which significantly limits its application. In this study, BP is successful doped into sol-gel glass, it shows excellent chemical stability in atmospheric environment for five months. In addition, as a kind of inorganic matrix, optical damage threshold of BP-doped sol-gel glass reaches as high as 51.69 GW/cm2, which is six times higher than that of plastic polymer. Saturable absorption parameters of the BP are maintained after five months in the air. The BP-doped sol-gel glass is inserted into erbium-doped fiber (EDF) laser to realize passively Q-switched and mode locked operation. Compared to most Q-switched EDF lasers based on broadband absorbers, the single pulse energy is one of the highest values (315.99 nJ). Overall, these data evidently provide a practical solution to stabilize BP in the air by embedding it in the silica, and also open the way for extensive applications of BP.

Lasers in general are operated using a cavity resonant with emitters. In this study, the authors demonstrated a laser operating under an anti-resonant condition, where the emitter resonance is equally detuned from two Fabry–Perot fringes. This configuration may pave the way for reducing the laser linewidth and cavity pulling effect.

Abstract With the innovation of microelectronics technology, the heat dissipation problem inside the device will face a severe test. In this work, cellulose aerogel (CA) with highly enhanced thermal conductivity (TC) in vertical planes was successfully obtained by constructing a vertically aligned silicon carbide nanowires (SiC NWs)/boron nitride (BN) network via the ice template-assisted strategy. The unique network structure of SiC NWs connected to BN ensures that the TC of the composite in the vertical direction reaches 2.21 W m−1 K−1 at a low hybrid filler loading of 16.69 wt%, which was increased by 890% compared to pure epoxy (EP). In addition, relying on unique porous network structure of CA, EP-based composite also showed higher TC than other comparative samples in the horizontal direction. Meanwhile, the composite exhibits good electrically insulating with a volume electrical resistivity about 2.35 × 1011 Ω cm and displays excellent electromagnetic wave absorption performance with a minimum reflection loss of − 21.5 dB and a wide effective absorption bandwidth (

Abstract Background Osmanthus fragrans is an evergreen plant with high ornamental and economic values. However, they are easily injured by salt stress, which severely limits their use in high salinity areas. The trihelix transcription factor (TF) family, as one of the earliest discovered TF families in plants, plays an essential part in responses to different abiotic stresses, and it has potential functions in improving the salt-tolerance capability of O. fragrans. Results In this study, 56 trihelix genes (OfGTs) were first identified in O. fragrans and then divided into five subfamilies in accordance with a phylogenetic tree analysis. The OfGTs were found to be located randomly on the 20 O. fragrans chromosomes, and an analysis of gene replication events indicated that the OfGT gene family underwent strong purification selection during the evolutionary process. The analysis of conserved motifs and gene structures implied that the OfGT members in the same subfamily have similar conserved motifs and gene structures. A promoter cis-elements analysis showed that all the OfGT genes contained multiple abiotic and hormonal stress-related cis-elements. The RNA-seq data suggested that the OfGTs have specific expression patterns in different tissues, and some were induced by salt stress. The qRT-PCR analysis of 12 selected OfGTs confirmed that OfGT1/3/21/33/42/45/46/52 were induced, with OfGT3/42/46 being the most highly expressed. In addition, OfGT42/OfGT46 had a co-expression pattern under salt-stress conditions. OfGT3/42/46 were mainly localized in the nuclei and exhibited no transcriptional activities based on the analysis of the subcellular localization and transcriptional activity assay. Furthermore, the expression levels of most of the selected OfGTs were induced by multiple abiotic and hormonal stresses, and the expression patterns of some OfGTs were also highly correlated with gibberellic acid and methyl jasmonate levels. Remarkably, the transient transformation results showed lower MDA content and increased expression of ROS-related genes NbAPX in transgenic plants, which implying OfGT3/42/46 may improve the salt tolerance of tobacco. Conclusions The results implied that the OfGT genes were related to abiotic and hormonal stress responses in O. fragrans, and that the OfGT3/42/46 genes in particular might play crucial roles in responses to salt stress. This study made a comprehensive summary of the OfGT gene family, including functions and co-expression patterns in response to salt and other stresses, as well as an evolutionary perspective. Consequently, it lays a foundation for further functional characterizations of these genes.

Hydrogen (H2) as an environmentally friendly and sustainable energy carrier has been regarded as one of the most promising alternatives to carbon‐based fossil fuels. Electrochemical water splitting powered by renewable electricity provides a promising strategy for H2 production, but its energy efficiency is strongly limited by the kinetically sluggish anodic oxygen evolution reaction (OER), which consumes ≈90% electricity in the water‐splitting process. A new strategy is urgently needed to reduce its energy consumption. Small‐molecule electro‐oxidation reactions that replace OER have attracted increasing attention due to the advantages of low theoretical thermodynamic potential and the benefit of producing value‐added chemicals compared with OER. Hybrid electrolysis systems, by coupling cathodic hydrogen evolution reaction (HER) with anodic small‐molecule oxidation reactions, have been proposed, which can produce high‐purity H2 and value‐added products. This review aims to systematically summarize the recent research on OER‐alternative reactions at the anode for energy‐efficient water splitting. The state‐of‐the art electrocatalysts for OER‐alternative reactions are first presented. The electrolysis performance in hybrid electrolysis regarding the conversion rate, selectivity, yield, and corresponding Faraday efficiency of anodic value‐added products is then evaluated. Finally, the challenges and perspectives are discussed and it is suggested to develop energy‐efficient and economically viable hybrid electrolysis systems.

High-speed machining of γ-TiAl alloy is a significant challenge due to high cutting temperatures. From the perspective of environmental protection and improving tool life, appropriate cooling strategies should be adopted. Compared with dry and conventional flood cooling conditions, the feasibility of machining γ-TiAl in cryogenic LN2 cooling conditions was discussed. The cutting force, tool wear and its mechanism, and surface roughness, as well as sub-surface morphology characteristics, were studied by combining macro and micro techniques. The results revealed that the wear morphology of the rake and flank face under the three cooling media shows different degrees. The crater wear of the rake face is expanded at high speeds and then progresses into more serve flaking and notching wear. The main wear pattern on the flank face is gradually transformed from adhesive wear to diffusion and oxidation wear at high speeds in dry machining. In the LN2 condition, the diffusion of workpiece elements and cutting-edge oxidation were restrained. The wear pattern is still mainly adhesive wear. In addition, cryogenic machining shows significant advantages in reducing cutting force, suppressing heat-affected zone, improving surface quality, and inhibiting micro-lamellar deformation.

Supercapacitor is an imminent potential energy storage system, and acts as a booster to the batteries and fuel cells to provide necessary power density. In the last decade, carbon and carbonaceous materials, conducting polymers and transition metal oxide/hydroxide based electrode materials have been made to show a remarkable electrochemical performance. Rare-earth materials have attracted significant research attention as an electrode material for supercapacitor applications based on their physicochemical properties. In this review, rare earth metals, rare earth metal oxides/hydroxides, rare-earth metal chalcogenides, rare-earth metal/carbon composites and rare-earth metal/metal oxide composites based electrode materials are discussed for supercapacitors. We also discuss the energy chemistry of rare-earth metal-based materials. Besides the factors that affect the performance of the electrode materials, their evaluation methods and supercapacitor performances are discussed in details. Finally, the future outlook in rare-earth-based electrode materials is revealed towards its current developments for supercapacitor applications.

Abstract The controllable construction of two-dimensional (2D) metal–organic framework (MOF) nanosheets with favorable electrochemical performances is greatly challenging for energy storage. Here, we design an in situ induced growth strategy to construct the ultrathin carboxylated carbon nanotubes (C-CNTs) interpenetrated nickel MOF (Ni-MOF/C-CNTs) nanosheets. The deliberate thickness and specific surface area of novel 2D hybrid nanosheets can be effectively tuned via finely controlling C-CNTs involvement. Due to the unique microstructure, the integrated 2D hybrid nanosheets are endowed with plentiful electroactive sites to promote the electrochemical performances greatly. The prepared Ni-MOF/C-CNTs nanosheets exhibit superior specific capacity of 680 C g−1 at 1 A g−1 and good capacity retention. The assembled hybrid device demonstrated the maximum energy density of 44.4 Wh kg−1 at a power density of 440 W kg−1. Our novel strategy to construct ultrathin 2D MOF with unique properties can be extended to synthesize various MOF-based functional materials for diverse applications.

The Faraday laser, with Faraday anomalous dispersion optical filter (FADOF) as frequency-selection element, is a natural narrow-bandwidth light source for laser physic experiments. In this work, a dual-frequency (DF) Faraday laser is demonstrated for the first time on Cs D2 line at 852 nm. The frequencies of the two modes of DF Faraday laser hinge on the peak transition frequencies of 852 nm FADOF transmittance spectrum corresponding to the ground state F=4 and F=3. The frequency difference between the two modes is tunable over a range of 1.4 GHz with the temperature of Cs vapor cell inside the FADOF. The linewidth of each laser mode is less than 33 kHz. Furthermore, the most probable linewidth of the beat-note spectra between the two modes is 902.95 Hz at different vapor-cell temperatures. Such a DF Faraday laser has many potential applications in atomic physics, such as sub-Doppler spectroscopy and coherent population trapping atomic clocks.

With the involution of pedestrian detection technology, higher requirements are put forward for the detection accuracy under the conditions of insufficient light, target occlusion, and too small scale. Without information and multiscale pedestrian target, visible light single-mode pedestrian detection algorithm has poor performance. To solve the above problems, a pedestrian detection algorithm combining attention mechanism and nonmaximum suppression method is proposed in this study, aiming to improve the accuracy of pedestrian detection. In addition, residual network ResNet-50 and IoU (intersection over union) loss function are also adopted to improve pedestrian detection accuracy. Attention mechanism was used to optimize and highlight pedestrian area features, and meanwhile, the nonmaximum suppression method was applied to improve the robustness of the algorithm. Experimental results show that the detection accuracy of the proposed algorithm is significantly higher than that of the traditional convolutional neural network algorithm.

The energy levels arising from the electronic orbital 5p−4f crossing between the ground 5p24f and excited 5p4f2 configurations in the Nd9+ ion are investigated by using high-accuracy relativistic ab initio calculations. The accurate atomic data of the lifetime, gJ factor, electric quadrupole moment, and hyperfine structure of the magnetic dipole are also presented. The long-lived states that are suitable for making narrow-linewidth (milli-Hz) clock lines are found. Dominant systematics caused by stray electromagnetic interactions in an experiment and the coefficients of the relativistic sensitivityto variation of the fine-structure constant α and of the Lorentz invariance violation are evaluated, thus validating that the Nd9+ ion can be a new candidate for high-resolution spectroscopy and precision fundamental studies for probing new physics beyond the Standard Model.

Using a hollow-cathode lamp (HCL) to build a Faraday anomalous dispersion optical filter (FADOF) is a new method to realize narrow linewidth optical filters. In contrast to other atomic optical filters based on saturated vapors, which work at a relatively high temperature to maintain the atomic density, the HCL device using sputtered particles can work at a much lower temperature. In this work, a rubidium HCL-based FADOF (HCL-FADOF) working at 780 nm is established and carefully tested. With 20 mm cathode length, the transmittance can reach 29% under 18 mA discharge current and 260 G magnetic field at room temperature, which is equivalent to the performance of a saturated vapor-based FADOF (VC-FADOF) at more than 60 ∘C. This work provides a direct comparison of the performance of the HCL-FADOF and the VC-FADOF, which is of great benefit to further studies of atomic filters at normal temperature.

Considering the strong inhomogeneous spatial polarization and intensity distribution of spontaneous decay fluorescence due to the Hanle effect, we propose and demonstrate a universe Hanle detection configuration of electron-shelving method for optical clocks. Experimental results from Ca atomic beam optical frequency standard with electron-shelving method show that a designed Hanle detection geometry with optimized magnetic field direction, detection laser beam propagation and polarization direction, and detector position can improve the fluorescence collection rate by more than one order of magnitude comparing with that of inefficient geometry. With the fixed 423 nm fluorescence, the improved 657 nm optical frequency standard signal intensity is presented. The potential application of the Hanle detection geometry designed for facilitating the fluorescence collection for optical lattice clock with a limited solid angle of the fluorescence collection has been discussed. The Hanle detection geometry is also effective for ion detection in ion optical clock and quantum information experiments. Besides, a cylinder fluorescence collection structure is designed to increase the solid angle of the fluorescence collection in Ca atomic beam optical frequency standard.

An emerging issue in wildlife conservation is the re-establishment of viable populations of endangered species in suitable habitats. Here, we studied habitat selection by a population of Hainan Eld's deer (Cervus eldi) relocated to a patchy landscape of farmland and forest. Hainan Eld's deer were pushed to the brink of extinction in the 1970s, but their population expanded rapidly from 26 to more than 1000 individuals by 2003 through effective reserve protection. As part of a wider relocation and population management strategy, 131 deer were removed from the reserve and reintroduced into a farmland-forest landscape in 2005. Habitat use under a context of human disturbance was surveyed by monitoring 19 radio-collared animals. The majority of deer locations (77%) were within 0.6-2 km of villages. Annual home ranges of these collared deer averaged 725 ha (SD 436), which was 55% of the size of the reserve from which they had originated. The annual home ranges contained 54% shrub-grassland, 26% forest and 15% farmland. The relocated deer population selected landscape comprising slash-and-burn agriculture and forest, and avoided both intensively farmed areas and areas containing only forest. Within the selected landscape, deer preferred swiddens and shrub-grasslands. Forests above 300 m in elevation were avoided, whereas forests below 300 m in elevation were overrepresented during the dry season and randomly used during the wet season. Our findings show that reintroduced deer can utilize disturbed habitats, and further demonstrate that subsistence agroforest ecosystems have the capacity to sustain endangered ungulates.

Gas source localization is one of the most common applications of a gas-sensitive mobile robot. However, most of the existing work focuses on rule-based algorithms for wheeled robots, which are difficult to apply in complex terrain with obstacles. In this article, we propose an olfactory quadruped robot to perform the gas source localization task using the Dueling Deep Q-Network (Dueling DQN) algorithm. For training, we designed a set of environments and imported gas dispersion data from computational fluid dynamics (CFD) software to construct a simulator. The olfactory quadruped robot was trained in this simulator using the Dueling DQN algorithm to learn how to find the gas source. The trained neural network was then deployed on the olfactory quadruped robot. Our method has been tested in both simulation and real environments. The olfactory quadruped robot can traverse rugged terrain in real experiments and efficiently find gas sources, demonstrating that our method is highly robust and has important practical value. [ABSTRACT FROM AUTHOR]

Indium oxide (In2O3) doped zinc oxide (ZnO) nanocomposites were successfully synthesized through a facile microwave hydrothermal method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption isotherms (BET) and UV-Vis diffuse reflectance spectroscopy. The morphology of In2O3-ZnO composites was observed to be like flowers, and the diameter of particles constituting the porous petal was about 30 nm. The photoelectrocatalytic test results showed that the photoelectrocatalytic methylene blue (MB) degradation efficiency using In2O3-ZnO nanocomposites as photocatalysts under visible light irradiation and a certain voltage could reached above 95.3% after 60 min, much higher than that of In2O3 particles and ZnO particles. The enhanced photoelectrocatalytic activity was attributed to the doping of In2O3 and applied voltage, which beneficially reduced the recombination of electrons and holes in the photoelectrocatalytic process, therefore, it promoted the production of active species (•OH and •O-2). [ABSTRACT FROM AUTHOR]

human populations expand and nonhuman animals decline, understanding the interactions between people and wildlife is essential. For endangered species, appreciating the effect of human disturbance can be important for their conservation. However, a human disturbance angle is often absent from ecological research, despite growing evidence of the negative impact of nonfatal human interference. Here, we monitored Hainan Eld's deer living within a reserve and translocated animals living amongst villagers. We show that translocated deer deviated from a crepuscular activity pattern and became increasingly nocturnal, and most active when villagers were not. It appears that translocated deer adapted over time to human disturbance and this pattern is similar to that of other species during periods of hunting. People do not pose an actual threat to Eld's deer, but their presence triggered a response akin to predator avoidance and may be interfering with broader aspects of their biology and conservation. [ABSTRACT FROM AUTHOR]

Abstract Background Gamithromycin is an effective therapy for bovine and swine respiratory diseases but not utilized for rabbits. Given its potent activity against respiratory pathogens, we sought to determine the pharmacokinetic profiles, antimicrobial activity and target pharmacokinetic/pharmacodynamic (PK/PD) exposures associated with therapeutic effect of gamithromycin against Pasteurella multocida in rabbits. Results Gamithromycin showed favorable PK properties in rabbits, including high subcutaneous bioavailability (86.7 ± 10.7%) and low plasma protein binding (18.5–31.9%). PK analysis identified a mean plasma peak concentration (Cmax) of 1.64 ± 0.86 mg/L and terminal half-life (T1/2) of 31.5 ± 5.74 h after subcutaneous injection. For P. multocida, short post-antibiotic effects (PAE) (1.1–5.3 h) and post-antibiotic sub-inhibitory concentration effects (PA-SME) (6.6–9.1 h) were observed after exposure to gamithromycin at 1 to 4× minimal inhibitory concentration (MIC). Gamithromycin demonstrated concentration-dependent bactericidal activity and the PK/PD index area under the concentration-time curve over 24 h (AUC24h)/MIC correlated well with efficacy (R2 > 0.99). The plasma AUC24h/MIC ratios of gamithromycin associated with the bacteriostatic, bactericidal and bacterial eradication against P. multocida were 15.4, 24.9 and 27.8 h in rabbits, respectively. Conclusions Subcutaneous administration of 6 mg/kg gamithromycin reached therapeutic concentrations in rabbit plasma against P. multocida. The PK/PD ratios determined herein in combination with ex vivo activity and favorable rabbit PK indicate that gamithromycin may be used for the treatment of rabbit pasteurellosis.

We demonstrate a Faraday laser using a 1.2 km fiber as an extended cavity, which provides optical feedback and obtains small free spectrum range (FSR) of 83 kHz, and have succeeded in limiting the laser frequency to a crossover transition of the natural 87Rb at 780 nm. The Faraday laser is based on a Faraday anomalous dispersion optical filter (FADOF) with an ultra-narrow bandwidth and the long fiber extended cavity of 1.2 km. The peak transmission assigned to the crossover transition in the FADOF is 20.5% with an ultra-narrow bandwidth of 29.1 MHz. The Allan deviation of the Faraday laser is around in 0.06 to 1 s sampling time. Laser frequency is always kept in the center of the transmitted peak assigned to . The Faraday laser realized here can provide light exactly resonant with an atomic transition used for atom–photon interaction experiments and is insensitive to diode temperature and injection current fluctuations. [ABSTRACT FROM AUTHOR]