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Background: Sinosenecio B. Nordenstam (Asteraceae) currently comprises 44 species. To investigate the interspecific relationship, several chloroplast markers, including ndhC-trnV, rpl32-trnL, matK, and rbcL, are used to analyze the phylogeny of Sinosenecio. However, the chloroplast genomes of this genus have not been thoroughly investigated. We sequenced and assembled the Sinosenecio albonervius chloroplast genome for the first time. A detailed comparative analysis was performed in this study using the previously reported chloroplast genomes of three Sinosenecio species. Results: The results showed that the chloroplast genomes of four Sinosenecio species exhibit a typical quadripartite structure. There are equal numbers of total genes, protein-coding genes and RNA genes among the annotated genomes. Per genome, 49–56 simple sequence repeats and 99 repeat sequences were identified. Thirty codons were identified as RSCU values greater than 1 in the chloroplast genome of S. albonervius based on 54 protein-coding genes, indicating that they showed biased usage. Among 18 protein-coding genes, 46 potential RNA editing sites were discovered. By comparing these chloroplast genomes' structures, inverted repeat regions and coding regions were more conserved than single-copy and non-coding regions. The junctions among inverted repeat and single-copy regions showed slight difference. Several hot spots of genomic divergence were detected, which can be used as new DNA barcodes for species identification. Phylogenetic analysis of the whole chloroplast genome showed that the four Sinosenecio species have close interspecific relationships. Conclusions: The complete chloroplast genome of Sinosenecio albonervius was revealed in this study, which included a comparison of Sinosenecio chloroplast genome structure, variation, and phylogenetic analysis for related species. These will help future research on Sinosenecio taxonomy, identification, origin, and evolution to some extent. [ABSTRACT FROM AUTHOR]

In this study, flow and heat transfers in bidisperse gas–solid systems were numerically investigated using the computational fluid dynamics–discrete element method (CFD–DEM). Three different models to close the gas–solid heat transfer coefficient for each species of bidisperse systems were compared in the simulations. The effect of the particle diameter ratio and particle number ratio between large and small particles on the particle mean temperature and temperature distribution of each species were systematically investigated. The simulation results show that differences in the particle mean temperature and temperature distribution profiles exist among the three heat transfer models at a higher particle number ratio. The differences between the effects of three heat transfer models on heat transfer properties in bidisperse systems with particle diameter ratios of up to 4 are marginal when the particle number ratio between small and large particles is 1. [ABSTRACT FROM AUTHOR]

Background: The maintenance of nucleus pulposus (NP) viability in vitro is difficult. The annulus fibrosus (AF) pathway reflects one nutrient transport channel and may have an important effect on NP viability in disc organ cultures. The present study describes a feasible disc pre-treatment involving the AF and investigates its efficacy in improving NP bioactivity in an in vitro disc bioreactor culture.Methods: Rabbit discs that were randomly assigned to the experimental group (EG) were pretreated via the surgical removal and controlled trypsinization of the outer AF. The discs in the control group (CG) did not receive any special treatment. All discs were organ-cultured in a self-developed bioreactor. Solute transport into the central NP was measured using a methylene blue solution. On days 7 and 14, histological properties, cell viability, cell membrane damage, gene expression and matrix composition within the NP in these two groups were compared with each other and with the corresponding parameters of fresh NP samples. Additionally, the structures of the outer AF and the cartilage endplate (CEP) following pre-treatment were also assessed.Results: The outer AF in the EG became disorganized, but no specific changes occurred in the CEP or the inner AF following pre-treatment. The discs in the EG exhibited increased penetration of methylene blue into the central NP. On days 7 and 14, the NP bioactivity in the EG was improved compared with that of the CG in terms of cell viability, cell membrane damage, gene expression profile and matrix synthesis. Moreover, cell viability and matrix synthesis parameters in the EG were more similar to those of fresh samples than they were to the same parameters in the CG on day 14.Conclusions: Using this disc pre-treatment, i.e., the surgical removal and controlled trypsinization of the outer AF, NP bioactivity was better maintained for up to 14 days in an in vitro disc bioreactor culture. [ABSTRACT FROM AUTHOR]

Purpose: To compare the efficacy, safety, and technical characteristics of anterior-only and posterior-only approach surgeries for the treatment of consecutive multisegment thoracic and lumbar tuberculosis. Methods: Thirty-five patients who developed consecutive multisegment thoracic and lumbar tuberculosis from September 2012 to May 2016 were retrospectively analyzed. Group A was the posterior-only surgery group, and group B was the anterior-only surgery group. The data on the surgery, deformity correction, functional scores, and complications were compared between the two groups. Results: There was no significant difference in the operation time or blood loss between groups A and B (P > 0.05). The preoperative average Cobb angle of kyphosis in groups A and B were 36.2 ± 15.2° and 27.9 ± 7.7°, respectively, which significantly decreased to 4.9 ± 11.8° and 10.4 ± 5.6° after the operation, respectively (P < 0.05). At the final follow-up, the angles were 7.1 ± 10.5° and 14.6 ± 8.0°. The correction angle and correction rate in group A (31.3 ± 16.6°, 88.6 ± 43.6%) were greater than those in group B (17.5 ± 4.4°, 64.9 ± 14.0%) (P < 0.05). There was no significant difference in the loss angle between groups A and B (P > 0.05), but the loss rate in group B (24.0 ± 27.8%) was higher than that in group A (9.6 ± 10.2%) (P < 0.05). There was no significant difference in the incidence of complications between the two groups (P > 0.05). Conclusion: The posterior-only and anterior-only approaches can lead to satisfactory clinical results in the treatment of patients with consecutive multisegment thoracic and lumbar tuberculosis. With posterior-only surgery, kyphosis can be better corrected, and the correction can be better maintained than with anterior-only surgery. [ABSTRACT FROM AUTHOR]