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We proposed a far-infrared tunable metamaterial absorber using vanadium dioxide (VO2) and graphene as controlling materials. The properties of the absorber are investigated theoretically using the finite-difference time-domain (FDTD) technique. It was found that when the Fermi energy level of graphene is fixed at zero, VO2 is in the insulated state, and the metasurface exhibits far-infrared broadband absorption performance, with absorptance exceeding 90% in the wavelength range of 12.6 μm to 23.2 μm. In addition, by elevating the Fermi energy level of graphene, the absorption bandwidth of the device is expanded continuously. When the VO2 is in the metallic state, the device can flexibly transform into a far-infrared narrowband absorber. The device also has the advantage of being insensitive to changes in polarization and incident angle. The origin of the absorption and the tuning principle of the device were analyzed and verified successfully by using an equivalent circuit model (ECM). Besides, we also studied the refraction index sensing characteristics of the absorber. Surprisingly, the absorber exhibits excellent sensing characteristics, and its sensitivity (S) reaches 14.108 μm per RIU and the figure of merit (FOM) is 6.13 per RIU. [ABSTRACT FROM AUTHOR]

Background: The adverse effects of pulmonary arterial hypertension (PAH) on physical, emotional, and health-related quality of life (HRQoL) remain primarily unrecognized, especially in resource-limited settings. Objectives: This study aims to characterize the HRQoL of patients with PAH in this area and also identify the potential role of clinically relevant characteristics, including the 6-min walk distance test (6MWD), WHO-Functional Classification (WHO-FC), and mental health in the occurrence of lowering quality of life. Design: This was a cross-sectional observational study. Methods: Inpatients with PAH were chosen from a tertiary hospital located in Gansu province, China. All participants were interviewed face-by-face by using questionnaires, including items from the 36-Item Short Form Health Survey (SF-36), the self-rating anxiety scale, and the self-rating depression scale. Data on demographic and clinically relevant characteristics, including WHO-FC and 6MWD, were also collected by tracing medical recorders. Multiple linear regression analysis was used to determine the association between demographic, clinically relevant characteristics data, and physical component summary (PCS) or mental component summary (MCS) in SF-36. Results: Of the 152 participants, SF-36 differed significantly from Chinese norms in all eight domains, with role-physical (21.55 ± 9.87) less than one-third of the norm (88.79 ± 28.49). Multiple linear regression results showed that the factors with the greatest impact on PCS were anxiety scores (β = −0.22, p = 0.001), followed by WHO-FC (β = −0.16, p = 0.014) and 6MWD (β = 0.15, p = 0.036). The factors with the greatest impact on MCS were WHO-FC (β = −0.30, p < 0.001), followed by anxiety (β = −0.23, p = 0.001) and depression scores (β = −0.16, p = 0.013). Conclusion: HRQoL was substantially reduced among PAH patients in the resource-limited area, mainly the physiological functions. WHO-FC and anxiety scores were independently associated with both PCS and MCS in SF-36. Clinicians should make reasonable rehabilitation programs and plans for patients according to their cardiac function grade and the severity of clinical symptoms. In addition, psychological interventions should also be taken, especially for those with anxiety symptoms, so as to improve their HRQoL. [ABSTRACT FROM AUTHOR]

Root rot of Paris polyphylla has received widespread attention due to its threat to yield and leads to serious economic losses. However, the relationship among the rhizosphere microbial community, metabolites and root rot disease remained largely unexplored. Herein, we used integrated 16S rRNA, ITS, RNA sequencing and UPLC-MS/MS to systematically investigate the differences between healthy and diseased P. polyphylla. We found that root rot reduced the microbial diversity in the diseased P. polyphylla compared with the healthy control. The relative abundance of the bacterial phylum Actinobacteria increased in the diseased rhizome of P. polyphylla. For the fungal community, root rot disease contributed to an increased relative abundance of Ascomycota and decreased Glomeromycota at the phylum level. The transcriptomic results showed that the differently expressed genes were significantly enriched in the "Biosynthesis of various alkaloids", "flavonoid biosynthesis" and "isoflavonoid biosynthesis" and "Phenylpropanoid biosynthesis" was dramatically enriched in healthy P. polyphylla compared with that in diseased P. polyphylla. Likewise, the metabolomic results showed that the biosynthesis of secondary metabolites and metabolic pathways was found to be significantly enriched by differential metabolites. Taken together, the study of combining metabolomics with microbiomes can help us enhance our understanding of the mechanisms of plant resistance to root rot disease, thereby discovering specific metabolites and microorganisms that can resist pathogen infection in P. polyphylla. [ABSTRACT FROM AUTHOR]

The metabolic networks underlying skotomorphogenesis in seedlings remain relatively unknown. On the basis of our previous study on the folate metabolism in seedlings grown in darkness, the plastidial folylpolyglutamate synthetase gene (AtDFB) T‐DNA insertion Arabidopsis thaliana mutant (atdfb‐3) was examined. Under the nitrate‐sufficient condition, the mutant exhibited deficient folate metabolism and hypocotyl elongation, which affected skotomorphogenesis. Further analyses revealed changes to multiple intermediate metabolites related to carbon and nitrogen metabolism in the etiolated atdfb‐3 seedlings. Specifically, the sugar, polyol, and fatty acid contents decreased in the atdfb‐3 mutant under the nitrate‐sufficient condition, whereas the abundance of various organic acids and amino acids increased. In response to nitrate‐limited stress, multiple metabolites, including sugars, polyols, fatty acids, organic acids, and amino acids, accumulated more in the mutant than in the wild‐type control. The differences in the contents of multiple metabolites between the atdfb‐3 and wild‐type seedlings decreased following the addition of exogenous 5‐F‐THF under both nitrogen conditions. Additionally, the mutant accumulated high levels of one‐carbon metabolites, such as Cys, S‐adenosylmethionine, and S‐adenosylhomocysteine, under both nitrogen conditions. Thus, our data demonstrated that the perturbed folate metabolism in the atdfb‐3 seedlings, which was caused by the loss‐of‐function mutation to AtDFB, probably altered carbon and nitrogen metabolism, thereby modulating skotomorphogenesis. Furthermore, the study findings provide new evidence of the links among folate metabolism, metabolic networks, and skotomorphogenesis. [ABSTRACT FROM AUTHOR]