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Background Gut microbiota and microbiota-derived metabolites have been implicated in the regulation of stress-related diseases, yet their associations with chronic stress in adolescents remain unclear. Multi-omics studies on this topic in adolescents are still limited. This study aimed to characterize gut microbiota and metabolites in adolescents under chronic stress. Methods In this cross-sectional study, we assessed chronic stress in 124 adolescents aged 12–16 years using the Adolescent Life Events Scale and the Study Stress Scale. Participants were stratified by stress level into low ( n  = 42), medium ( n  = 41), and high stress ( n  = 41) groups. Fecal samples were collected from all participants for 16S rRNA gene sequencing. Subsequently, a subset of 30 adolescents with high stress and 29 low stress adolescents underwent metagenomic sequencing and untargeted metabolomics. Results Adolescents experiencing high-chronic stress showed lower alpha diversity, differential beta diversity, and a more complicated microbial network compared to those experiencing lower stress. Spearman’s rank correlation and Kruskal-Wallis test identified five genera with decreased abundances in high stress adolescents, including Faecalibacterium , Bacteroides , Akkermansia , Lachnospiraceae unclassified , and Ruminococcus ( P fdr <0.05). Additionally, 12 species showed decreased abundances and 5 increased abundances, and logistic regression analysis further revealed that the relative abundances of Bifidobacterium catenulatum , Streptococcus suis , Ruminococcus sp. CAG 108 , and Phascolarctobacterium faecium were associated with chronic stress ( P fdr <0.05), after adjusting for sex, age, fruit consumption, and body mass index. We identified 21 differential metabolites, predominantly enriched in metabolic pathways based on KEGG analysis. Moreover, 19 out of these metabolites were significantly correlated with at least one of the four species significantly associated with chronic stress. These metabolites may explain health effects of species associated with chronic stress. Conclusions Chronic stress in adolescents is associated with altered gut microbiota composition and metabolite profiles, providing insights into possible mechanisms underlying stress-related diseases and highlighting the importance of longitudinal studies to clarify temporal and causal relationships.

Establishing appropriate metal-support interactions is imperative for acquiring efficient and corrosion-resistant catalysts for water splitting. Herein, the interaction mechanism between Ru nanoparticles and a series of titanium oxides, including TiO, Ti 4 O 7 and TiO 2, designed via facile non-stoichiometric engineering is systematically studied. Ti 4 O 7, with the unique band structure, high conductivity and chemical stability, endows with ingenious metal-support interaction through interfacial Ti–O–Ru units, which stabilizes Ru species during OER and triggers hydrogen spillover to accelerate HER kinetics. As expected, Ru/Ti 4 O 7 displays ultralow overpotentials of 8 mV and 150 mV for HER and OER with a long operation of 500 h at 10 mA cm −2 in acidic media, which is expanded in pH-universal environments. Benefitting from the excellent bifunctional performance, the proton exchange membrane and anion exchange membrane electrolyzer assembled with Ru/Ti 4 O 7 achieves superior performance and robust operation. The work paves the way for efficient energy conversion devices. Establishing optimal metal-support interactions is crucial for creating efficient catalysts for water splitting. Here, stable Ti–O–Ru interface formation and minimal work function difference between Ru nanoparticles and non-stoichiometric Ti4O7 lead to exceptional bifunctional activity of Ru/Ti4O7 for both HER and OER across pH-universal environments, maintaining stable operation for 500 h.

This paper presents a thorough robust Class-AB power amplifier design and its application in pressure-mode sensor-on-chip nonlinearity correction. Considering its use in piezoresistive sensing applications, a gain-boosting-aided folded cascode structure is utilized to increase the amplifier’s gain by a large amount as well as enhancing the power rejection ability, and a push–pull structure with miller compensation, a floating gate technique, and an adaptive output driving limiting structures are adopted to achieve high-efficiency current driving capability, high stability, and electronic environmental compatibility. This amplifier is applied in a real sensor nonlinearity correction on-chip system. With the help of a self-designed 7-bit + sign DAC and a self-designed two-stage operational amplifier, this system is compatible with nonlinear correction at different signal conditioning output values. It can also drive resistive sensors as small as 300 ohms and as high as tens of thousands of ohms. The designed two-stage operational amplifier utilizes the TSMC 0.18 um process, resulting in a final circuit power consumption of 0.183 mW. The amplifier exhibits a gain greater than 140 dB, a phase margin of 68°, and a unit gain bandwidth exceeding 199.76 kHz. The output voltage range spans from 0 to 4.6 V. The final simulation results indicate that the nonlinear correction system designed in this paper can correct piezoresistive sensors with a nonlinearity of up to ±2.5% under various PVT (Process–Voltage–Temperature) conditions. After calibration by this system, the maximum error in the output voltage is 4 mV, effectively reducing the nonlinearity to 4% of its original value in the worst-case scenario.

Developing ruthenium-based oxide catalysts capable of suppressing lattice oxygen participation in the catalytic reaction process is crucial for maintaining stable oxygen evolution reaction (OER) under acidic conditions. Herein, we delicately construct a RuO 2 nanoparticle-anchored LiCoO 2 nanosheet electrocatalyst (RuO 2 /LiCoO 2 ), achieving dynamic optimization of RuO 2 during the reaction process and improving catalytic stability. Benefiting from the unique electrochemical delithiation characteristics of the LiCoO 2 support, the covalency of the Ru-O bond is effectively regulated during the OER process. The weakened Ru-O covalent bond inhibits the participation of lattice oxygen in the catalytic reaction and ensures the continuous operation of the Ru active sites. Moreover, the extended Ru-O bond in the optimized RuO 2 /LiCoO 2 catalyst reduces the formation energy barrier of the *OOH intermediates, accelerating the progress of the OER. As a result, the RuO 2 /LiCoO 2 catalyst requires only an overpotential of 150 ± 2 mV at 10 mA cm −2 in 0.5 M H 2 SO 4 and operates stably for 2000 h at 1 A cm −2 in a proton exchange membrane water electrolysis. This work opens new avenues for designing efficient ruthenium-based catalysts. Long-term stability is a key challenge for ruthenium-based oxygen evolution reaction (OER) catalysts. Here, the authors present a RuO2/LiCoO2 catalyst with dynamic Li dissolution, which weakens the covalency of the Ru-O bond to prevent the lattice oxygen mechanism, thereby ensuring stable acidic OER.

Depth distribution is an important trait for scleractinian corals, reflecting their adaptability and vulnerability. However, it remains to be quantified and analyzed adequately in turbid coral communities. Here, we used underwater photogrammetry to explore the depth distribution of turbid coral communities in China’s Greater Bay Area (GBA). Surveys at the five sites revealed that the depth distribution of GBA coral communities ranged from − 0.91 m to -5.70 m, with an average depth of -3.41 m. The depth distribution of coral communities at different sites varied significantly, showing an increasing trend from inside to outside of Dapeng Bay. Coral cover and generic richness generally showed a unimodal pattern with increasing depth, with peaks in the depth range of -2 to -4 m. Coral genera exhibited significant differences in their distribution depths, and there were variations in generic composition across different depth ranges, suggesting that GBA coral communities exhibited zonation despite their limited depth ranges.

Inspired by the wave-rider idea and momentum principle, the vehicle with inverted dihedral and momentum lift augmentation is a new aerodynamic configuration of high-speed gliding vehicle in the near-space, which has achieved a high lift-to-drag ratio and long-distance sliding. Numerical simulation of aerodynamic characteristics and stability of the aircraft are carried out in this paper. The lift-to-drag characteristics, longitudinal-directional stability and lateral-directional stability are evaluated based on the National Numerical Wind tunnel’s high-speed simulation software, named NNW-HyFLOW. An unstructured/hybrid grid is used in the calculation at the typical ballistic points of altitude of 10-75km and Mach number of 3-25. The results shows that the lift-to-drag ratio reaches a peak value of 4.11 at the altitude of 30km and attack angle of 8°. This value is decreased when the altitude raises. The usable lift-to-drag ratio is over 3 in the glide phase range from 30 to 50 kilometres. This vehicle shows better longitudinal-directional stability at large angles of attack than at small in the reentry phase and glide phase, which can be optimized by adjusting the center of mass or pitching rudder. It has a weak instability in the lateral direction at small angle of attack in the glide phase. Therefore, it is suggested to avoid to work at the high altitude with a small angle of attack. Or, the lateral-directional stability can be strengthened at this altitude by improving the V-tail.

The fish intestine is a complex ecosystem where microbial communities are dynamic and influenced by various factors. Preservation conditions during field collection can introduce biases affecting the microbiota amplified during sequencing. Therefore, establishing effective, standardized methods for sampling fish intestinal microbiota is crucial. This study used hybrid groupers ( Epinephelus fuscoguttatus  ♀ ×  E. lanceolatus  ♂) to examine the effects of six preservation methods: dry ice (1 day), dry ice (1 day) followed by – 80 °C storage (5 days), liquid nitrogen (1 day), liquid nitrogen (1 day) with subsequent – 80 °C storage (5 days), refrigeration at 4 °C (3 days), and freezing at – 20 °C (3 days), with fresh samples as controls. High-throughput 16S rRNA sequencing assessed microbial diversity, community structure, dominant species, and OTU abundance across treatments. Results indicated that dry ice and liquid nitrogen methods, especially with – 80 °C storage, had minimal impact on microbial diversity and structure. Compared to other preservation methods, refrigeration at 4 °C and freezing at – 20 °C may result in suboptimal reproducibility and altered community structure, particularly affecting rare microbial taxa. This study underscores the need for standardized preservation techniques to ensure accurate fish intestinal microbiota analysis and provides a foundation for future research.

Sensitive avalanche photodetectors (APDs) that operate within the ultraviolet spectrum are critically required for applications in detecting fire and deep-space exploration. However, the development of such devices faces significant challenges, including high avalanche breakdown voltage, the necessity for complex quenching circuits, and thermal runaway associated with Geiger-mode avalanche operation. To mitigate these issues, we report on a 4H-SiC APD design utilizing micro-holes (MHs) structures and Al nano-triangles (NTs) to enhance surface electric field driven by strong localized surface plasmon excitations and lightning-rod effect. The device demonstrates a low avalanche breakdown voltage of approximately 14.5 V, a high detectivity of 2 × 10 13 Jones, a nanosecond-level response time, and repeated stable detections without the requirement of a quenching circuit. Collectively, when compared with the conventional wide-bandgap-based APDs, this device achieves a reduction in avalanche breakdown voltage by an order of magnitude. Consequently, the proposed APD configuration presents a promising candidate for ultraviolet detection and integrated optoelectronic circuits. This study presents an approach to enhancing the local field of avalanche photodetectors by integrating the lightning-rod effect with localized surface plasmon excitations.

PurposeSoil macropores affect the proportion of rainfall infiltration and regulate the amount of water available to the plants on a field scale. However, the distribution of soil macropores and the effect on hydrologic and ecological regimes have been underestimated at a continental scale. The aim of this study was to investigate the relationships between soil properties and climatic factors on soil macropores and assess the eco-hydrological effect of soil macropores.Materials and methodsWe hypothesized that the spatial distribution of soil macropores was controlled by soil properties and climatic factors at the continental scale. Using a spatial error-egression method, the soil effective porosity (EP) and residual effective porosity (REP) across China were calculated. The effects of soil macropores on soil physicochemical properties and climate factors were analyzed by the random forest model. The effect of macropores on soil water content (SWC) and normalized difference vegetation index (NDVI) was also analyzed.Results and discussionThe EP ranged from 0.06 to 0.35 cm3 cm−3 and was significantly related with soil chemical index, particularly, negatively correlated with cation exchange capacity (CEC) and total nitrogen (TN), but positively correlated with pH. There was a negative relationship between REP and mean annual precipitation in drylands. In humid regions, there was a positive relationship between REP and mean annual precipitation. Random forest model showed in humid region mean annual precipitation was more important than the annual temperature difference in explaining REP, but the results were reversed in drylands. The SWC and NDVI had different correlations with REP in drylands and humid regions.ConclusionSoils with better quality had lower EP at the continental scale. Soil macropores were related simultaneously to precipitation and temperature conditions. Importantly, soil macropores were not conducive to soil water conservation and vegetation development in drylands.

Capturing semantics and structure surrounding the target entity pair is crucial for relation extraction. The task is challenging due to the limited semantic elements and structural features of the target entity pair within a sentence. To tackle this problem, this paper introduces an approach that fuses entity-related features under convolutional neural networks and graph convolution neural networks. Our approach combines the unit features of the target entity pair to generate corresponding fusion features and applies the deep learning framework to extract high-order abstract features for relation extraction. Experimental results from three public datasets (ACE05 English, ACE05 Chinese, and SanWen) indicate that the proposed approach achieves F1-scores of 77.70%, 90.12%, and 68.84%, respectively, highlighting its effectiveness and robustness. This paper provides a comprehensive description of the approach and experimental results.