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Sweet potato provides rich nutrients and bioactive substances for the human diet. In this study, the volatile organic compounds of five pigmented-fleshed sweet potato cultivars were determined, the characteristic aroma compounds were screened, and a correlation analysis was carried out with the aroma precursors. In total, 66 volatile organic compounds were identified. Terpenoids and aldehydes were the main volatile compounds, accounting for 59% and 17%, respectively. Fifteen compounds, including seven aldehydes, six terpenes, one furan, and phenol, were identified as key aromatic compounds for sweet potato using relative odor activity values (ROAVs) and contributed to flower, sweet, and fat flavors. The OR sample exhibited a significant presence of trans-β-Ionone, while the Y sample showed high levels of benzaldehyde. Starch, soluble sugars, 20 amino acids, and 25 fatty acids were detected as volatile compounds precursors. Among them, total starch (57.2%), phenylalanine (126.82 ± 0.02 g/g), and fatty acids (6.45 μg/mg) were all most abundant in Y, and LY contained the most soluble sugar (14.65%). The results of the correlation analysis revealed the significant correlations were identified between seven carotenoids and trans-β-Ionone, soluble sugar and nerol, two fatty acids and hexanal, phenylalanine and 10 fatty acids with benzaldehyde, respectively. In general, terpenoids and aldehydes were identified as the main key aromatic compounds in sweet potatoes, and carotenoids had more influence on the aroma of OR than other cultivars. Soluble sugars, amino acids, and fatty acids probably serve as important precursors for some key aroma compounds in sweet potatoes. These findings provide valuable insights for the formation of sweet potato aroma.

Lithium is a rare metal widely used in the renewable energy industry. The Altyn region in Xinjiang, China, contains abundant granitic pegmatite-type lithium resources; however, the deeply incised and complex terrain limits the accuracy of conventional two-dimensional remote sensing approaches for dike identification and segmentation. To address this limitation, a remote sensing segmentation method incorporating terrain information was proposed. A digital elevation model (DEM) derived from LiDAR data, together with its associated topographic factors, was integrated into the Spatial–Spectral Mamba framework to enable the joint utilization of spectral and terrain features. Rather than performing explicit three-dimensional geometric modeling, the proposed approach enhances a two-dimensional segmentation framework by introducing elevation-derived information, allowing the model to capture terrain-related spatial variations of pegmatite dikes. This design enables improved representation of both the planar distribution and terrain-influenced morphological characteristics of dikes under deeply incised conditions. The Xichanggou lithium deposit in the Altyn region is a large-scale, economically valuable pegmatite-type lithium deposit, and was therefore selected as the study area for pegmatite dike segmentation. The results demonstrated that, compared with conventional two-dimensional approaches and representative machine learning methods, the proposed method achieved higher segmentation accuracy in complex terrain. Improvements were also observed in the continuity and spatial consistency of the extracted dike patterns. Field verification indicated that the major pegmatite dikes delineated by the model were highly consistent with their actual surface exposures. Sampling analyses further confirmed the validity and reliability of the identification results. Overall, the terrain-integrated remote sensing segmentation approach exhibited good applicability and robustness under deeply incised and complex geomorphological conditions.

Aiming at the problem of serious deformation and difficult support in the surrounding rock of the near-vertical coal–rock-interbedded roadway, this paper studies the stress distribution characteristics of the roadway surrounding the rock based on the engineering geological conditions of the Wudong coal mine, in particular with the +400 level B8 centralized transportation roadway. Meanwhile, both the deformation and destabilization characteristics of the roadway surrounding the rock is studied. The distribution of the plastic zone is numerically studied via the FLAC3D program. The research results showed that: the averaged maximum horizontal principal stress is 24.3 MPa, which is about 3.08 times of the vertical principal stress. The deformation and damage of the near-vertical coal–rock-interbedded roadway is asymmetrical, and the stress distribution of the roadway surrounding the rock shows obvious discontinuous characteristics. Moreover, the plastic zone of the roadway surrounding the rock is featured with the shear damage. It also suggests that the force of gravity along the coal–rock layer direction increases when the normal load at the level of the near-vertical coal–rock layer is relatively small. The overhanging area of the roof and the unconfined range of the floor increased, which was attributed to the shear slip damage, whereas the flexural deformation is produced under the effect of tectonic stress, which results in the instable mechanism of “the ribs heave, roof subsidence and floor heave” for near-vertical coal–rock-interbedded roadway.

Camellia drupifera is an important woody oil crop with high economic and medicinal value. Fruit maturation is a complex process regulated by hormones and gene networks, yet its molecular basis remains unclear. Here, we integrated hormone profiling (IAA, GA3, ABA), transcriptomics, and miRNA-omics across three key stages: nutrient synthesis (S1), lipid accumulation (S4), and maturation (S7). During early development (S1), IAA and GA3 levels peaked, accompanied by the upregulation of growth-related genes (AUX1, ARF, GID1), which promote fruit growth. By maturation (S7), ABA content increased markedly, activating PYR/PYL, PP2C, and ABF, while IAA and GA3 declined. Transcriptome analysis revealed 45 key differentially expressed genes correlated with hormone levels. In parallel, miRNAs such as miR393-z (targeting TIR1) and novel-m0146-5p (targeting ARF1) were identified as regulators of hormone signaling and fruit maturation. Collectively, our results highlight a coordinated “hormone–miRNA–mRNA” regulatory network underlying C. drupifera fruit development. These findings provide new insights into the molecular regulation of fruit maturation and lipid accumulation in woody oil crops, offering a foundation for genetic improvement and efficient utilization of this species.

Purple-fleshed sweetpotatoes (PFSPs) are rich in anthocyanins and are one of the health foods of interest. In this study, the effects of steaming on the anthocyanin, starch, soluble sugar, volatile organic compounds (VOCs) and pasting properties of nine PFSPs from China were investigated. The anthocyanin content of raw PFSP ranged from 9 to 185 mg/100 g. The total starch content decreased and soluble sugar content increased in all purple potatoes after steaming. Among the nine PFSPs varieties, Guangshu20 showed the greatest decrease in starch content (30.61%) and the greatest increase in soluble sugar content (31.12%). The pasting properties affected the taste of the PFSPs, with Shuangpihuang having the lowest peak viscosity (720.33 cP) and Guangzishu12 having the highest peak viscosity (2501.67 cP). Correlation studies showed that the anthocyanin content and pasting properties were negatively correlated with most of the sensory indicators, whereas the soluble sugar content of steamed PFSPs was significantly positively correlated with sweetness. A total of 54 VOCs were identified in this study, and aldehydes and terpenoids were the major VOCs in PFSPs. This study provides a theoretical basis for the processing of different PFSP varieties.

This study investigated the effects of exogenous melatonin (MT) on the physiological responses of Camellia hainanica seedlings under drought stress, using the drought-tolerant variety “Hai Da 1” and the drought-sensitive variety “Wan Hai 1” as test materials. Seedlings were treated with MT at concentrations of 0, 50, 100, 150, 200, and 250 μmol/L through irrigation, followed by drought stress induced by polyethylene glycol (PEG-6000). The results revealed that MT alleviated growth damage caused by PEG-simulated drought stress, with leaf relative conductivity and malondialdehyde (MDA) content showing an initial decrease followed by an increase as MT concentration rose. In contrast, relative water content, chlorophyll content, antioxidant enzyme activity, secondary metabolite levels, and carbohydrate content initially increased and then declined with increasing MT concentration. Treatment with 200 μmol/L MT notably reduced MDA content by 40–50%, enhanced antioxidant enzyme activity by 20–30%, and increased secondary metabolite levels by 11–42% in the drought-sensitive variety. These findings identified 200 μmol/L MT as the optimal concentration for mitigating drought stress in C. hainanica seedlings, providing a foundation for its practical application in C. hainanica production and further research into the drought resistance mechanisms mediated by MT.

The carbonized PAF-1 derivatives formed by high-temperature KOH activation showed a unique bimodal microporous structure located at 0.6 nm and 1.2 nm and high surface area. These robust micropores were confirmed by nitrogen sorption experiment and high-resolution transmission electron microscopy (TEM). Carbon dioxide, methane and hydrogen sorption experiments indicated that these novel porous carbon materials have significant gas sorption abilities in both low-pressure and high-pressure environments. Moreover the methane storage ability of K-PAF-1-750 is among the best at 35 bars and its low-pressure gas adsorption abilities are also comparable to the best porous materials in the world. Combined with excellent physicochemical stability, these materials are very promising for industrial applications such as carbon dioxide capture and high-density clean energy storage.

Cyclopropane-based aerospace fuels exhibit the excellent volumetric calorific value, leading to broad application prospects in aircrafts. However, due to the highly rigid structure of the cyclopropane (compared to cyclobutane or cyclopentane, etc.) and the difficulty in forming metal-carbene intermediates, there are still significant challenges in the precise synthesis of multi-cyclopropane-based high-energy fuels ( ≥ 2 cyclopropane structures). Herein, via the introduction of bending strain on metal organic complex, we report a single-site Cu/single-walled carbon nanotube catalyst (Cu/SWCNT), which possesses 2.6-fold conversion (up to 77.4%) and 4-fold selectivity (up to 45.7%) as that without bending strain for the preparation of bi-cyclopropane-based fuels from dienes. XAFS and DFT calculations show that bending strain enhances the upward shift of d-band center of β electrons (−4.370 to −4.366), thus promotes the adsorption and activation of CH 2 N 2 and alkenes. Moreover, bending strain elongates Cu-O bonds (1.91 to 1.96 Å), making it easier for CH 2 N 2 to insert and form Fischer carbene intermediates. These two aspects obviously reduce the reaction energy barrier from 40.3 to 33.7 kcal·mol -1 for the cyclopropanation process. Our work provides a method of strain engineering to regulate C-C coupling reactions at the molecular level, and achieve highly efficient cyclopropanation from alkenes. Cyclopropane fuels offer high energy density but are hard to synthesize due to rigid structures. Here, a strain-engineered Cu/SWCNT catalyst enhances carbene formation, boosting conversion and selectivity for multi-cyclopropane fuel production from dienes.

Deep learning-based methods for real-time small target detection are critical for applications such as traffic monitoring, land management, and marine transportation. However, achieving high-precision detection of small objects against complex backgrounds remains challenging due to insufficient feature representation and background interference. Existing methods often struggle to balance multi-scale feature enhancement and computational efficiency, particularly in scenarios with low target-to-background contrast. To address this challenge, this study proposes an efficient detection method called hierarchical feature enhancement and feature fusion YOLO (HFEF2-YOLO), which is based on the hierarchical dynamic attention. Firstly, a Hierarchical Filtering Feature Pyramid Network (HF-FPN) is introduced, which employs a dynamic gating mechanism to achieve differentiated screening and fusion of cross-scale features. This design addresses the feature redundancy caused by fixed fusion strategies in conventional FPN architectures, preserving edge details of tiny targets. Secondly, we propose a Dynamic Spatial–Spectral Attention Module (DSAM), which adaptively fuses channel-wise and spatial–dimensional responses through learnable weight allocation, generating dedicated spatial modulation factors for individual channels and significantly enhancing the saliency representation of dim small targets. Extensive experiments on four benchmark datasets (VEDAI, AI-TOD, DOTA, NWPU VHR-10) demonstrate the superiority of HFEF2-YOLO; the proposed method can reach an accuracy of 0.761, 0.621, 0.737, and 0.969 (in terms of mAP@0.5), outperforming state-of-the-art methods by 3.5–8.1%. Furthermore, a lightweight version (L-HFEF2-YOLO) is developed via dynamic convolution, reducing parameters by 42% while maintaining >95% accuracy, demonstrating real-time applicability on edge devices. Robustness tests under simulated degradation (e.g., noise, blur) validate its practicality for satellite-based tasks.

Hemophagocytic lymphohistiocytosis (HLH) secondary to Pneumocystis jirovecii pneumonia (PJP) is extremely rare in children. We present the case of a 10-year-old girl with a history of idiopathic thrombocytopenic purpura (ITP) on long-term oral prednisone, who was admitted for progressive fever, cough, and dyspnea. Metagenomic next-generation sequencing of blood and bronchoalveolar lavage fluid confirmed PJP. Despite targeted antifungal therapy and respiratory support, she developed persistent high-grade fever, pancytopenia, hyperferritinemia, hypofibrinogenemia, and hemophagocytosis on bone marrow aspirate by day 10, meeting diagnostic criteria for HLH. Genetic testing was declined by the parents. Management included dexamethasone, continuous renal replacement therapy, and plasmapheresis. Unfortunately, her condition deteriorated, and she was discharged upon parental request on day 22, succumbing on the same day. To our knowledge, this is the first reported pediatric case of HLH secondary to PJP in China. This case highlights that in children with PJP—especially those on immunosuppressive therapy—the development of persistent fever and cytopenia should prompt immediate evaluation for secondary HLH to enable timely intervention.