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Middle and low frequency band sound waves have strong penetration and diffraction abilities during the propagation process, making it difficult to attenuate. The control of middle and low frequency broadband sound waves has become a challenging topic. Therefore, it is necessary to develop new materials or structures with middle and low frequency sound absorption, insulation, and noise reduction functions. The special properties of acoustic metamaterial provide new ideas for the development of sound absorption and insulation. In order to effectively control the noise in the lower frequency band, a new spatial spiral acoustic metamaterial was designed. First, the mechanism of band gap characteristics of a new spatial spiral acoustic metamaterial is analyzed. Then, a new spatial spiral acoustic metamaterial is completed through the finite element software COMSOL Multiphysics and the calculation and analysis of sound absorption and insulation performance in the 100–2500 Hz frequency band are completed. With the help of 3D printing, the preparation of metamaterial is completed, and the comparative experimental study of sound absorption and insulation performance of spiral acoustic metamaterial is carried out to verify the accuracy of the calculation method. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effect of curcumin on wound healing in deep tissue pressure injury(DTPI) induced by ischemia-reperfusion in mice. Methods Mice were randomly divided into control group (Con), model group (Mod), 4 and 8 mg/kg curcumin treatment group (Cur 4, Cur 8), 10 mice in each group. A deep tissue pressure injury model was established by magnet compression. The wounds tissue was injected with curcumin every 48 hours and photographed to observe the wound healing. HE staining was used to observe the pathological changes of wound healing. Real-time PCR was used to detect the mRNA expression of TNF-α, IL-6, IL-10, VEGF-α and TGF-β. Western blot was used to detect the expression of VEGF-α, TGF-β, Stat3 and p-Stat3. Results Compared with the control group, the wound in the model group gradually deteriorated, and the pathological changes were obvious. Compared with the model group, the wound healing of the Cur 8 group was significantly accelerated (P＜0.05). Compared with the model group, the inflammatory cell infiltration was reduced and the neovascular density was increased in the Cur 8 group. The mRNA expression of TNF-α and IL-6 in the wound tissues of the Cur 8 group was less than those in the model group, while the expression of IL-10, VEGF-α and TGF-β was higher than those in the model group (P＜0.05). The expression of VEGF-α, TGF-β and p-Stat3 in Cur 8 group was higher than those in model group (P＜0.05). Conclusions Curcumin administration can alleviate DTPI of mice induced by ischemia-reperfusion, and its mechanism may be related to the inhibition of inflammatory response and promotion of angiogenesis.

Methyl vinyl silicone rubber and methyl vinyl phenyl silicone rubber were used as the matrix, silica and boron phenolic resin (BF) were added for mixing, a light ablative heat insulation material was prepared. The density of the heat insulation material, the ablative performance of the heat insulation material under oxygen-acetylene flame and the back temperature of the material in the ablative process were studied. The results showed that with the addition of BF, the density of thermal insulation materials decreased significantly. When the amount of BF was 40 phr and 50 phr (mass, the same below), the density was 0.816 7 g/cm3 and 0.752 8 g/cm3 respectively, which was 29.35% and 34.88% lower than that without BF. With the increasing amount of BF, the mass ablation rate and linear ablation rate of the thermal insulation material increased, but the addition of BF could enhance the thermal insulation performance of the material. When 40 phr BF were added, the maximum back temperature was only 78 ℃.

Introduction: This study aimed to assess the impact of gamma knife radiosurgery on brainstem cavernous malformations (CMs). Methods: A total of 85 patients (35 females; median age 41.0 years) who underwent gamma knife radiosurgery for brainstem CMs at our institute between 2006 and 2015 were enrolled in a prospective clinical observation trial. Risk factors for hemorrhagic outcomes were evaluated, and outcomes were compared across different margin doses. Results: The pre-radiosurgery annual hemorrhage rate (AHR) was 32.3% (44 hemorrhages during 136.2 patient-years). The median planning target volume was 1.292 cc. The median margin and maximum doses were 15.0 and 29.2 Gy, respectively, with a median isodose line of 50.0%. The post-radiosurgery AHR was 2.7% (21 hemorrhages during 769.9 patient-years), with a rate of 5.5% within the first 2 years and 2.0% thereafter. The post-radiosurgery AHR for patients with margin doses of ≤13.0 Gy (n = 15), 14.0–15.0 Gy (n = 50), and ≥16.0 Gy (n = 20) was 5.4, 2.7, and 0.6%, respectively. Correspondingly, transient adverse radiation effects were observed in 6.7 (1/15), 10.0 (5/50), and 30.0% (6/20) of cases, respectively. An increased margin dose per 1 Gy (hazard ratio: 0.530, 95% CI: 0.341–0.826, p = 0.005) was identified as an independent protective factor against post-radiosurgery hemorrhage. Margin doses of ≥16.0 Gy were associated with improved hemorrhagic outcomes (hazard ratio: 0.343, 95% confidence interval [CI]: 0.157–0.749, p = 0.007), but an increased risk of adverse radiation effects (odds ratio: 3.006, 95% CI: 1.041–8.677, p = 0.042). Conclusion: The AHR of brainstem CMs decreased following radiosurgery, and our study revealed a significant dose-response relationship. Margin doses of 14–15 Gy were recommended. Further studies are required to validate our findings. [ABSTRACT FROM AUTHOR]

Ormosia is a genus of the Fabaceae family that shows a distinct evolutionary history due to its typical Asian-American tropical disjunction distribution pattern. However, both its phylogeny and biogeographic mechanisms have not been fully resolved. In addition, Ormosia species have great economic and ecological potential in the wood and handicraft (using their attractive seeds) industries, reforestation, and folk medicine (due to their flavonoids, alkaloids, and terpenoids), making them highly valuable in research, especially from a genomic perspective. We report the genome assemblies of two common Ormosia species, Ormosia emarginata and Ormosia semicastrata, in South China, using both long and short sequencing reads. The genome assemblies of O. emarginata and O. semicastrata comprised 90 contigs with a total length of 1,420,917,605 bp and 63 contigs with a total length of 1,511,766,959 bp, respectively. Benchmarking Universal Single-Copy Orthologs (BUSCO) assessment revealed 97.0% and 98.3% completeness of the O. emarginata and O. semicastrata assemblies, respectively. The assemblies contain 48,599 and 52,067 protein-coding genes, respectively. Phylogenetic analyses using 1032 single-copy genes with 19 species indicated that they are closely related to Lupinus albus. We investigated genes related to plant hormones, signaling, the circadian rhythm, transcription factors, and secondary metabolites derived from the whole genome and tandem and proximal duplications, indicating that these duplications should play important roles in the growth, development, and defense of Ormosia species. To our knowledge, our study is the first report on Ormosia genome assemblies. This information will facilitate phylogenetic and biogeographic analyses and species breeding in the future. [ABSTRACT FROM AUTHOR]