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Railway station reconstruction adjacent to existing twin tunnels has been a challenging problem, as the former can impose heavy loads on the latter. As a result, the existing twin tunnels may sustain damage. To address this problem, in this study, a design plan for a railway station reconstruction over twin tunnels was improved by optimising the cross-section form and installing a buffer layer (XPS). Model tests were employed to investigate the mechanical behaviour of a railway station reconstruction over twin tunnels and the earth pressure in the surrounding rock, and an assessment of the safety of the existing tunnel lining was also performed. The numerical modelling was validated by an experiment based on the comparison of reinforcement strain, concrete stress, and failure pattern, particularly, the tensile-shear failure. In addition, the parametric study considering the different stiffness of the buffer layer was presented. These results comprehensively show the optimised design scheme not only addressed the very small clearance ranging from 1.46 m to 3.06 m but also reduced the construction cost including the decrease of concrete. As the stiffness of the buffer layer increases, the tunnel lining bears larger forces. The relatively low 10 MPa elastic modulus of buffer layer was recommended in this project. The valuable ideas, in this study, can potentially be generalized to similar projects for reducing the disturbance from the adjacent construction to the existing tunnels. [ABSTRACT FROM AUTHOR]

• Expression of StMBF1 genes induced by Ralstonia solanacearum had twice significant upregulated expression. • StMBF1c gene involved multiple signal pathways, including SA signal pathway ABA signal pathway. • StMBF1c interacting StTPS5 was confirmed by Y2H and BiFC. • StMBF1c was related to the potato defense response to bacterial wilt. Multiprotein bridging factor 1 (MBF1) is a transcription coactivator that has a general defense response to pathogens. However, the regulatory mechanisms of MBF1 resistance bacterial wilt remain largely unknown. Here, the role of StMBF1c in potato resistance to Ralstonia solanacearum infection was characterized. qRT-PCR assays indicated that StMBF1c could was elicited by SA, MJ and ABA and the time-course expression pattern of the StMBF1c gene induced by R. solanacearum was found to be twice significant upregulated expression during the early and middle stages of bacterial wilt. Combined with the co-expression analysis of disease-resistant marker genes, gain-of-function and loss-of-function assays demonstrated that StMBF1c was associated with defence priming. Overexpression or silencing the MBF1c could enhance plants resistance or sensitivity to R. solanacearum through inducing or reducing NPR and PR genes related to SA signal pathway. Yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) experiment results confirmed the interaction of StMBF1c with StTPS5 which played a key role in ABA signal pathway in potato. It is speculated that by combining StTPS5 and resistance marker genes, StMBF1c is activated twice to participate in potato bacterial wilt resistance, in which EPI, PTI involved. [ABSTRACT FROM AUTHOR]

In this study, the polyphenol oxidase (PPO) activity of whole potatoes was inhibited by ultrasound. A 17-run Box-Behnken Design was used to optimize the ultrasound conditions for inhibiting the PPO activity. Three factors of ultrasound treatment including power, time, and temperature were investigated. Moreover, the effects of ultrasound treatment on the PPO activity of ultrasound-treated bruising damaged whole potatoes as well as on the micro-structure of the ultrasound-treated whole potatoes were evaluated. The adjusted coefficients of determination for models of Y 1 and Y 2 were 0.9980 and 0.9991, respectively. The p-values of two models for the responses were below 0.05, implying that the models can well represent PPO activities. The optimal ultrasound conditions were determined to be: ultrasound power 540 W, ultrasound time 15 min, and temperature 20 °C. Under these conditions, the mean PPO activities of the whole potatoes were 44.948 U/g, in accordance with the values predicted by the model. Besides, the PPO activity increases in the damaged whole potatoes. Nevertheless, the PPO activity of the ultrasound-treated whole potatoes was lower than that of untreated whole potatoes. Moreover, the power and time of ultrasound have a large impact on the micro-structures of the whole potatoes. • Polyphenol oxidase activity of whole potato was affected by ultrasound condition. • Response surface methodology was a useful tool for optimize the ultrasound condition. • The polyphenol oxidase activity of ultrasound-whole potato was increased by damage. • Ultrasound power and time have a large impact on micro-structures of whole potato. • The ultrasound has the potential for inhibiting the polyphenol oxidase activity. [ABSTRACT FROM AUTHOR]

Vanadium pentoxide (V 2 O 5) films were deposited on sapphire substrates by radio frequency (R.F.) magnetron sputtering at 450 °C and annealed in various ambient atmospheres. The influence of ambient atmospheres on the structure, optical properties, and morphology of the thin films after annealing were characterized, and the transition behaviors in the annealing process were investigated by DSC, temperature-dependent Raman and FTIR. The results demonstrated that V 2 O 5 films underwent four different transition behaviors during post-deposition annealing due to the different oxygen proportion of ambient. Different products (VO 2 (B), VO 2 (R)) in the transition process were the main reason for the evolution of optical properties. No transition behaviors occurred because of the oxygen-rich ambient when annealed in air, and no significant change in infrared transmittance was observed. When annealed in 0.1% O 2 /Ar, the film was converted to VO 2 (B) with the decrease of infrared transmittance. In the case of 0.01% O 2 /Ar, metastable VO 2 (B) and VO 2 (R) were observed as intermediate crystalline phases before V 2 O 5 finally transformed to VO 2 (M), and the changes in the three stages of two drops and one rise were shown in infrared transmittance. While annealed in pure argon ambient, V 2 O 5 was turned into VO 2 (R) and VO 2 (M) without VO 2 (B) phase production, accompanied by a single change of infrared transmittance reduction and recovery. This provides a more detailed vanadium oxide thermal transition process and shows data reference for the preparation technology and application of vanadium oxide materials. • V 2 O 5 films were deposited on sapphire substrates by radio frequency (R.F.) magnetron sputtering; • Effect of the different oxygen proportion during annealing on thermal transition behaviors was investigated in detail by temperature-dependent Raman and FTIR; • The annealed V 2 O 5 films were transformed into V 2 O 5 , VO 2 (B), and VO 2 (M) by different thermal transition behaviors; • VO 2 (M) films with excellent thermochromic properties can be obtained by controlling the annealing atmosphere and temperature. [ABSTRACT FROM AUTHOR]

The performance of atomic layer deposition films is mainly limited by precursor residues, low crystallinity and densities due to low deposition temperatures. Here, we used atomic layer deposition to deposit tin oxide thin films at a relatively low temperature of 250 °C. At this temperature, the change in the valence of Sn due to precursor residue is eliminated by layer-by-layer Ar plasma treatment, and the crystallinity of the films is improved. The effects of Ar plasma treatment power and Ar treatment time on the structural and optoelectronic properties were investigated. It was found that Ar plasma treatment time more significantly affects the surface morphology and the optical and electrical properties of the film. The film is transparent to both visible and near-infrared light over a wide range of wavelengths from 400 nm to at least 5000 nm. The film resistivity can be as low as 1.117 × 10−3 Ω·cm. The film has a relatively low level of residual stress due to the fact that there is no need to improve the crystallinity of the film by conventional high temperature annealing. On the basis of the high transparency and high conductivity of the SnOx films with layer by layer Ar plasma treatment in situ, the films can be applied as electromagnetic shielding windows for photodetectors. Unlabelled Image • The films exhibit excellent crystallinity and conductivity without the need for a high-temperature annealing step. • Ar plasma treatment significantly reduced the proportion of reduced Sn4+. • The plasma treatment time has a more pronounced effect on the SnOx crystallinity than the treatment power. • Designed and prepared an infrared transparent conductive film with excellent electrical properties and optical transmission [ABSTRACT FROM AUTHOR]

• Both reversible and irreversible transition were found in VO x films with different temperature. • Transmittance of VO x film were found undergoes twice reductions with temperature. • Mid infrared transmittance with ~64% modulation with temperature after the decomposition. • Temperature dependent Raman reveal the phase transition and decomposition process with temperature. In this study, mid infrared optical modulation property of VO x films with temperature was researched. VO x film which contain both VO 2 and V 2 O 5 was deposited on Al 2 O 3 substrate by radio frequency magnetron sputtering. The mid infrared transmittance undergoes two reductions when increasing the temperature to 590 °C, the first reversible reduction around 68 °C as the phase transition of VO 2 and the second irreversible gradually reduction starting around 350 °C because the oxidation state changed from V 2 O 5 to VO 2. The transmittance increased from 5.49% to 70.29% when cooling the temperature around 54℃. The film has the reversible 64% optical modulation around 60 °C during the second thermal cycling and keep stable even increased the temperature higher than 550 °C. The difference caused by high temperature thermal cycling in surface morphology structures, and chemical composition, were characterized by AFM, XRD, Raman, and XPS. The process of phase transition and the oxidation state changed during the thermal cycles were monitored with temperature dependent Raman spectra. This study provides new information about the transition between different structures and oxidation states of VO x film and a good candidate for infrared thermochromic window. [ABSTRACT FROM AUTHOR]

• A PDMS elastomer based on imine groups is successfully prepared using Schiff base reaction. • The elastomer features an outstanding optical transmittance more than 80% in visible region. • The elastomer exhibits good mechanical strength, stretchability, and excellent self-healing properties. • The elastomer is recyclable and can be used as adhesives. Smart materials with self-healing properties that can heal themselves with restored mechanical performance are highly desired. Herein, a transparent healable PDMS (HPDMS) elastomer based on imine bonds is successfully prepared from amino-modified polydimethylsiloxane (PDMS) and 1,4-diformylbenzene (DFB) through a simple method. The concentration of DFB has a great effect on the gelation process. The elastomer features an outstanding optical transmittance (more than 80%) over the full visible light region. The results of TGA and DSC indicate that the HPDMS elastomer is highly flexible at room temperature and can be used in a wide temperature range. The presence of imine bonding and the formation of Schiff base linkages is proved by the FT-IR and Raman spectra. The reversible imine bond can promote the contact of the fracture surfaces and result in quick and repeatable self-healing without any external intervention such as heat or light. Furthermore, the elastomer exhibits excellent recyclability and reprocessability. Besides, the adhesion test reveals the potential of the elastomer in application as adhesives. We anticipate that this strategy can be employed to prepare a transparent PDMS elastomer with mechanical strength, stretchable, and excellent self-healing properties. [ABSTRACT FROM AUTHOR]

• A self-powered vertical heterojunction photodetector based on n-SnOx/p-diamond was fabricated by RF sputtering. • The device has a peak response at 350 nm and responds to light wavelength in the 250–500 nm range at zero bias. • Analysis of the detection mechanism of the n-SnOx/p-diamond heterojunction photodetector. High-performance self-powered UV-blue photodetector was fabricated based on n-SnO x /p-diamond heterojunction. The SnO x film was deposited on the high temperature and high pressure synthetic boron doped diamond wafer by RF magnetron sputtering. This heterojunction device exhibits a good rectification behavior with a rectification ratio of 3.15 × 104 at ±3 V. At zero bias, the device responds in the wavelength ranging from 250 nm to 500 nm with a peak response at 350 nm. The photoresponse rise time and decay time of the device are both less than 2 s under UV-blue illumination with different wavelengths. These results demonstrate that the n-SnO x /p-diamond heterojunction device has potential applications in the field of UV-blue detection. [ABSTRACT FROM AUTHOR]

The complete chloroplast (cp) genome ofCurcuma flaviflora, a medicinal plant in Southeast Asia, was sequenced. The genome size was 160 478 bp in length, with 36.3% GC content. A pair of inverted repeats (IRs) of 26 946 bp were separated by a large single copy (LSC) of 88 008 bp and a small single copy (SSC) of 18 578 bp, respectively. The cp genome contained 132 annotated genes, including 79 protein coding genes, 30 tRNA genes, and four rRNA genes. And 19 of these genes were duplicated in inverted repeat regions. [ABSTRACT FROM AUTHOR]

• PPD improves survival and mitigates hematological injury of mice exposed to TBI. • PPD treatment alleviated TBI-induced damage to BM and spleen. • PPD increases the HSCs in BM and inhibits apoptosis in murine HSCs after TBI. • PPD can regulate TBI-induced redox balance. • PPD induced G-CSF and IL-6 production in mice after TBI. Agents that provide protection against irradiation-induced hematopoietic injury are urgently needed for radiotherapy. We examined the effects of the small molecule, 1,2-propanediol (PPD), on total body irradiation (TBI)-induced hematopoietic injury in C57BL/6 mice. PPD administration 1 h before TBI significantly increased hematopoietic parameters such as white blood cell, platelet, red blood cell, and lymphocyte counts in vivo and enhanced the survival of mice exposed to TBI (7.0 and 7.5 Gy). PPD administration 1 h before TBI improved bone marrow (BM) and spleen recovery after TBI, with increases in both BM cellularity and spleen index. The number of colony-forming-units in bone marrow mononuclear cells (BMNCs) in vitro also increased significantly. PPD pretreatment increased the numbers of hematopoietic stem cells and hematopoietic progenitor cells in BM. Importantly, PPD also maintained endogenous antioxidant status by decreasing levels of malondialdehyde and increasing the expression of reduced glutathione, superoxide dismutase and catalase in the serum of irradiated mice. PPD alleviated the levels of apoptosis in HSCs induced by TBI, thus increasing the proportion of dividing BMNCs. These results suggest that PPD protects against TBI-induced hematopoietic injury through the increased activities of antioxidant enzymes and the inhibition of apoptosis in HSCs. PPD increased the serum levels of granulocyte-colony stimulating factor and interleukin-6 irrespective of TBI. In conclusion, these data suggest that PPD acts as a radioprotector against radiation-induced hematopoietic injury. [ABSTRACT FROM AUTHOR]

Background: Ramie (Boehmeria nivea L.) is one of the most important natural fiber crops and an important forage grass in south China. Ramet number, which is a quantitative trait controlled by multigenes, is one of the most important agronomic traits in plants because the ramet number per plant is a key component of grain yield and biomass. However, the genetic variation and genetic architecture of ramie ramet number are rarely known. Results: A genome-wide association study was performed using a panel of 112 core germplasms and 108,888 single nucleotide polymorphisms (SNPs) detected using specific-locus amplified fragment sequencing technology. Trait-SNP association analysis detected 44 significant SNPs that were associated with ramet number at P < 0.01. The favorable SNP Marker20170–64 emerged at least twice in the three detected stages and was validated to be associated with the ramie ramet number using genomic DNA polymerase chain reaction with an F1 hybrid progeny population. Comparative genome analysis predicted nine candidate genes for ramet number based on Marker20170–64. Real-time quantitative polymerase chain reaction analysis indicated that six of the genes were specific to upregulation in the ramie variety with high ramet number. These results suggest that these genes could be considered as ramet number-associated candidates in ramie. Conclusions: The identified loci or genes may be promising targets for genetic engineering and selection for modulating the ramet number in ramie. Our work improves understanding of the genetics of ramet number in ramie core germplasms and provides tools for marker-assisted selection for improvement of agricultural traits. [ABSTRACT FROM AUTHOR]