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Sensitive and rapid identification of volatile organic compounds (VOCs) at ppm level with complex composition is vital in various fields ranging from respiratory diagnosis to environmental safety. Herein, we demonstrate a SERS gas sensor with size-selective and multiplexed identification capabilities for VOCs by executing the pre-enrichment strategy. In particular, the macro-mesoporous structure of graphene aerogel and micropores of metal-organic frameworks (MOFs) significantly improved the enrichment capacity (1.68 mmol/g for toluene) of various VOCs near the plasmonic hotspots. On the other hand, molecular MOFs-based filters with different pore sizes could be realized by adjusting the ligands to exclude undesired interfering molecules in various detection environments. Combining these merits, graphene/AuNPs@ZIF-8 aerogel gas sensor exhibited outstanding label-free sensitivity (up to 0.1 ppm toluene) and high stability (RSD=14.8%, after 45 days storage at room temperature for 10 cycles) and allowed simultaneous identification of multiple VOCs in a single SERS measurement with high accuracy (error < 7.2%). We visualize that this work will tackle the dilemma between sensitivity and detection efficiency of gas sensors and will inspire the design of next-generation SERS technology for selective and multiplexed detection of VOCs.

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Two-dimensional transition metal carbon/nitrides (MXenes) are promising candidates to revolutionize next-generation wearable sensors as high-performance surface-enhanced Raman scattering (SERS) substrates. However, low sensitivity of pure MXene nanosheets and weak binding force or uncontrolled in situ growth of plasmonic nanoparticles on hybrid MXene composites limit their progress toward universal and reliable sensors. Herein, we designed and manufactured a highly sensitive, structurally stable wearable SERS sensor by in situ fabrication of plasmonic nanostructures on the flexible TiVC membranes via the maximization of chemically reducing sites using alkaline treatment. DFT calculations and experimental characterization demonstrated that the hydroxyl functional groups on the surface of MXenes can facilitate the reduction of metal precursors and the nucleation of gold nanoparticles (AuNPs) and can be covalently attached to AuNPs. Thus, the fabricated flexible TiVC-OH-Au sensor satisfied the rigorous mechanical requirements for wearable sensors. In addition, combining the electromagnetic (EM) enhancement from dense AuNPs formed by the activation of nucleation sites and charge transfer (CT) between target molecule and substrate induced by the abundant DOS near the Fermi level of TiVC, the fabricated sensor exhibits ultrasensitivity, long-term stability, good signal repeatability, and excellent mechanical durability. Moreover, the proof-of-concept application of the wearable SERS sensor in sweat sensing was demonstrated to monitor the content of nicotine, methotrexate, nikethamide, and 6-acetylmorphine in sweat at the molecular level, which was an important step toward the universality and practicality of the wearable sensing technology.

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BACKGROUND: This retrospective study aimed to investigate the usefulness of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) for organ involvement and disease activity in newly diagnosed juvenile systemic lupus erythematosus (jSLE). METHODS: A total of 186 jSLE inpatients were included for analysis. All participants' clinical characteristics and laboratory data were obtained from medical records. The Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K) score scale was used to assess disease activity. Mann-Whitney U test and Kruskal-Wallis test were performed for non-parametric variables between the groups. Spearman rank correlation coefficient was used to analyze correlations between variables. RESULTS: The NLR was significantly higher in participants with serositis as compared those without serositis [2.72 (1.71-5.0) vs. 2.08 (1.42-3.15), P=0.038]. The PLR was significantly higher in participants manifesting symptoms of cutaneous rash [130.0 (92.6-235.0) vs. 112.0 (49.3-169.0), P=0.002], and arthritis [167.0 (106.0-243.0) vs. 106.0 (53.6-176.0), P<0.001], as compared to participants without such involvement. The PLR in participants with hematological involvement was significantly lower than in those without such involvement [111.0 (53.6-191.0) vs. 138.0 (107.0-185.0), P=0.016]. The PLR in participants with positive anti-Smith (anti-Sm) antibody was significantly higher than that in those with negative anti-Sm antibody [140.0 (91.6-228.0) vs. 114.0 (60.9-176.0), P=0.006]. The NLR showed positive correlations with serositis (r=0.153, P=0.037), complement C3 and C4 (r=0.152, P=0.038 and r=0.177, P=0.016, respectively). The PLR showed positive correlations with cutaneous rash (r=0.227, P=0.002), arthritis (r=0.290, P<0.001), anti-Sm antibodies (r=0.20, P=0.006) and erythrocyte sedimentation rate (ESR, r=0.159, P=0.03). Negative correlations were found between PLR and hematological involvement (r=-0.177, P=0.015). CONCLUSIONS: Both the NLR and PLR had correlations with serological indicators, and may predict organ involvement in jSLE, particularly cutaneous, arthritis, serositis, and haematological involvement.

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This study was carried out by the methods of typical plots investigation and laboratory test aiming at analyzing the survival state and fruiting characteristics of three Sinopodophyllum hexandrum populations in different environmental habitats. Meanwhile, it could provide scientific basis for enhancing wild population quantity recovery. The results showed that more population quantity grow in the habitats of large-area gap (Population A) and bushes (Population C) with a majority of the young individuals, while the minor-area gap (Population B) was the opposite. The development tendency of S. hexandrum populations would be the recession in the future. Spatial distribution pattern of populations was clumped at small scales but random at large scales. The indexes of population A and C, as fruit size，the quantity and quality of seeds，germ inability，were all superior to those of population B. Comparing the mainly environment factors of three populations, that favorable environmental factors for vegetative and reproductive growth of S. hexandrum populations were found，especially certain lighting intensity and fertile soil. Therefore, the favorable environmental habitats for S. hexandrum individuals growth could be artificial to promote the recovery and quantities of S. hexandrum populations in the future.

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