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Heating performance of biomass is of significant importance for the followed chemical reactions i.e. pyrolysis, gasification, combustion, etc. Corn straw (CS) is an important renewable resource. Microwave (MW) heating performances of corn straw particles affected by corn straw mass (10, 16, 22, 28 and 34 g), corn straw particle size (0.075, 0.125, 0.200, 0.355 and 0.600 mm) and microwave power (400, 450, 500, 550 and 600 W) were explored in detail in this study. It can be obtained that when the microwave powers were 400, 450, 500, 550 and 600 W, the average heating rates were 23.06, 33.19, 61.35, 88.70 and 101.46°C/min, respectively. When the corn straw particle sizes were 0.075, 0.125, 0.200, 0.355 and 0.600 mm, the average heating rates were 101.46, 61.07, 52.70, 37.34 and 56.04°C/min, respectively. When the corn straw masses were 10, 16, 22, 28 and 34 g, the average heating rates were 36.31, 46.24, 101.46, 92.95 and 46.01°C/min, respectively. Formulae were further proposed to estimate the transient temperatures of biomass particles, and the R2 values ranged from 0.984 to 0.999. [ABSTRACT FROM AUTHOR]

Fractal theory demonstrates significant merit in the feature expression of forms of matter in nature. This study uses fractal theory to study the backfill grouting of a shield tunnel. The seepage path was considered as a seepage mesh inserted into the rock-soil mass. For the fractal features of the seepage mesh, the formulas for the diffusion distance and the pressure contribution of grout were derived. The results showed that the diffusion equations of different grout patterns (Newtonian fluid and Bingham fluid) were of a uniform form after calculation, and the equations for the pressure distribution of grout with a change in radius were identical. The diffusion distance of grout increased with increasing grouting time, and there was no indication that the development of diffusion distance tended to be gradual; the downward tendency of the grout diffusion velocity was not moderated. The segment pressure increased with an increase in the diffusion distance. With a constant diffusion distance, a greater grouting pressure produced a greater segment pressure. The favorable performance of grout was attributed to an appropriate mixture ratio. An improper mixture ratio resulted in a smaller reinforcement area in the stratum, which impaired the stability of the shield tunnel. [ABSTRACT FROM AUTHOR]

Shield tunnel is widely adopted in the metro construction, and backfill grouting is the significant part. With power-law fluid grouts as the study object, a cylindrical infiltration diffusion model and spherical infiltration diffusion model are developed by applying the generalized Darcy law and theories of seepage mechanics based on the displacement effect of grout on groundwater. Through examples, the impact of factors including grouting pressure and formation permeability coefficient in the spherical displacement infiltration diffusion model on diffusion radius, flow rate, total pressure of grout in segments, and uniform equivalent pressure in grout diffusion area (grout pressure per unit area in a segment) is analyzed. The result shows that, the diffusion speed, injection flow rate and the pressure received in segments increase with an increase of the grouting pressure. Meanwhile, as the injection time increases, the flow rate of grout under conditions of different grouting pressure all decreases, and a sharp decrease exists. The diffusion speed and grouting pressure are positively correlated to the permeability coefficient, and with the increasement of the injection time, the diffusion displacement of grout in different permeability coefficient varies increasingly, the increase amplitude of the pressure acting on the segment by grout increases gradually. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the prevalence and clinical characteristics of myelinated retinal nerve fibre (MRNF) in a large teleophthalmology system. Methods: All records between January 2015 and December 2015 from Daheng Prust teleophthalmology system were reviewed by 2 ophthalmologists independently. MRNF was classified into continuous group and discontinuous group according to the relationship between MRNF patches and optic disc. The number, total area and location of MRNF patches were analysed. Concomitant ocular diseases were documented. Results: Out of 51469 subjects, MRNF was detected in 304 eyes of 263 subjects with a prevalence rate of 0.51 ± 7.1% per subject and 0.30 ± 5.4% per eye. Among 304 eyes with MRNF, 239 (78.6%) eyes were in continuous group and 65 (21.4%) eyes were in discontinuous group. Single MRNF patch was found in 249 (81.9%) eyes and multiple MRNF patches were found in 55 (18.1%) eyes. MRNF of small size was found in 150 (49.3%) eyes. The ratios of multiple MRNF patches and small-sized MRNF in the continuous group were significantly higher than those in the discontinuous group (P =.014 and P <.001). In continuous group, the MRNF patches were located most frequently in the superior region (68.6%) of the optic disc; In discontinuous group, the MRNF patches were located most frequently in the inferotemporal region (38.5%) of the retina. Epiretinal membrane (12 eyes, 3.9%) was the most common concomitant ocular disease. Conclusion: MRNF is uncommon in China. MRNF usually presents unilaterally and as a single small whitish patch that is connected with optic disc. [ABSTRACT FROM AUTHOR]

Under the combined impacts of the operation time, design concept, and construction technology, extensive damage has occurred in tunnels built in China during the early stages of rapid development. Therefore, relevant research on tunnel damage is of urgent importance. This study takes the Liupanshan Highway Tunnel on G312 in Guyuan City as a case study, and uses field investigations, radar scans, and other methods to investigate the occurrence of a series of defects in the tunnel, including lining splitting, water leakage, and tunnel bottom damage, to analyze the damage characteristics and occurrence mechanism in detail based on both external causes and internal causes. From the results, by combing relevant materials both in China and abroad with the engineering characteristics, a comprehensive management method for reinforcing and strengthening damaged tunnels with a reinforced concrete umbrella arch is proposed. At the same time, considering the degradation in the bearing capacity of the existing lining structure and utilization degree of the bearing capacity of newly increased reinforced concrete umbrella arch, this study performs a theoretical analysis of the calculation for the safety factor of the reinforced damaged tunnel. The calculation results show that the reinforced Liupanshan Tunnel is in a secure state, which can provide references for similar projects in the future. [ABSTRACT FROM AUTHOR]

Objectives: This study examined the associations between perceived crime-specific victimization risk, avoidance behavior, and their relationships with health of older adults. Method: A representative sample of 453 Chinese aged 60 and older from Kunming provided information on their socio-demographic characteristics, perceived crime victimization risk, avoidance behavior, physical and mental health. Results: Avoidance behavior was common among participants, with 61.4% avoiding unsafe areas and 42.2% avoiding social activities. Path analyses showed that perceived risk of vandalism was associated with avoiding participating in social activities, while perceived risk of attack was related to avoiding unsafe areas during the day. Meanwhile, avoiding social activities and perceived risk of vandalism were significant predictors of poor mental health, and avoiding unsafe areas was a salient predictor of poor physical health. Perceived risk of attack had an indirect effect on physical health through avoiding unsafe areas during the day. Conclusion: Study findings highlight the importance of addressing perceived victimization risk in encouraging social participation and mobility among older adults. [ABSTRACT FROM AUTHOR]

A novelin situcyclocondensation reaction of anp (anp = 2-amino-5-nitropyridine) and ethanol into L (L = 6-nitro-imidazo(1,2-a)pyridine) under solvothermal conditions has been observed for the first time. Crystal structure of a metal complex, CdL2I2(1), has been obtained. Complex1was synthesized from a solvothermal reaction of anp with CdI2in anhydrous ethanol and water. Complex1crystallizes in orthorhombic space groupPnmawitha= 13.662(9) Å,b= 16.734(11) Å,c= 8.767(5) Å. The structure of1shows mononuclear units. Weak hydrogen bonds and π···π stacking intermolecular interactions assemble units to form a 3-D supramolecular network of1. [ABSTRACT FROM PUBLISHER]

Mast cells play critical roles in allergic disorders such as atopic dermatitis and allergic asthma. The aim of this study was to investigate the anti-inflammatory and anti-asthmatic activities of 1,6-O,O-diacetylbritannilactone (OODBL) isolated fromInula japonicaThunb. (I. japonica) in a murine asthma model and bone marrow-derived mast cells (BMMCs). In an ovalbumin-induced asthma model, OODBL administration attenuated the airway hyper-responsiveness induced by aerosolized methacholine and serum IgE level in asthmatic mice.In vitrosystem, we found that OODBL reduced leukotriene C4production and degranulation through the suppression of cytosolic phospholipase A2phosphorylation and phospholipase Cγ-mediated Ca2+influx in IgE/antigen-stimulated BMMCs. Taken together, OODBL may have therapeutic potential in the treatment of allergic diseases such as asthma. [ABSTRACT FROM AUTHOR]

Under investigation in this paper is a cubic-quintic nonlinear Schrödinger equation which can describe the propagation of ultrashort pulses in an inhomogeneous optical fibre. Lax pair and conservation laws are constructed from which the integrability of the equation can be verified. Through a gauge transformation, spectral problem for the equation is converted to an Ablowitz–Kaup–Newell–Segur spectral problem. Nonautonomous solitons and breathers are derived based on the Darboux transformation (DT), while nonautonomous rogue waves are obtained via the generalized DT. Influence of the group-velocity dispersion, gain-or-loss coefficient and group-velocity coefficient on the propagation and interaction of the nonautonomous solitons, breathers and rogue waves is also discussed. The gain-or-loss coefficient influences the amplitude of nonautonomous soliton. The characteristic line and velocity for the nonautonomous soliton are dependent on the group-velocity dispersion and group-velocity coefficient, but independent of the gain-or-loss coefficient. For the second-order nonautonomous soliton, if the two spectral parameters have the same real part, the bound-state structure can be formed, and the intensity becomes amplified in the attractive procedure. There exist two types of the nonautonomous breathers. Quasi-periods for the nonautonomous breathers are given, and effects of those coefficients on the quasi-periods are also discussed: The group-velocity dispersion can influence the trajectories of the nonautonomous breathers and rogue waves, while the gain-or-loss coefficient affects the backgrounds for the nonautonomous breathers and rogue waves [ABSTRACT FROM PUBLISHER]

In our previous study, a derivative of tiliroside, 3-O-[(E)-4-(4-ethoxyphenyl)-2-oxobut-3-en-1-yl]kaempferol (Fla-OEt) significantly enhanced glucose consumption in insulin resistant HepG2 cells. This article deals with the antihyperglycemic and antihyperlipidemic effects of Fla-OEt in diet-induced obesity (DIO) mice. Daily administration of Fla-OEt significantly decreased oral glucose tolerance test, intraperitoneal insulin tolerance test and serum lipids. Hyperinsulinemic–euglycemic clamp and the ratio of high-density-lipoprotein/low-density-lipoprotein with Fla-OEt treatment were increased comparing with high-fat diet (HFD) group, so lipid metabolism was improved. Histopathology examination showed that the Fla-OEt restored the damage of adipose tissues and liver in DIO mice. Moreover, compared with HFD group, Fla-OEt treatment significantly increased the phosphorylation of AMPK and ACC in adiposity tissues, liver, and muscles. The mechanism of its action might be the activation of AMPK pathway. It appears that Fla-OEt is worth further study for development as a lead compound for a potential antidiabetic agent. [ABSTRACT FROM PUBLISHER]

Citrus australasica (F. Muell.) Swingle belongs to the family Rutaceae. Citrus australasica is native to eastern Australia and southeastern New Guinea, and is mainly concentrated in a small region of northern New South Wales and tropical rainforest areas in southern Queensland. The complete plastome length of C. australasica is 160,335 bp, with the typical structure and gene content of angiosperm plastids, including a 26,592 bp repeat B (IRB) region, 26,952 bp IRA, 87,678 bp large single copy (LSC) region and 18,756 bp small single copy (SSC) region. The plastid contains 135 genes, including 89 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The total G/C content of the C. australasica plastome is 38.4%. The complete plastome sequence of C. australasica will provide useful resources for conservation genetics research of this species and phylogenetic research of Rutaceae. [ABSTRACT FROM AUTHOR]

Three new pregnane alkaloids, named terminamines H–J (1–3), together with two known alkaloids (4 and 5), were isolated from the ethanol extract of Pachysandra terminalis. The structures of isolated compounds were elucidated by spectroscopic methods, including 1H and 13C NMR, 2D NMR, and HR-ESI-MS. Compounds 1, 4, and 5 revealed significant anti-metastasis activities. In addition, compound 1 inhibited the expression of p-PKCζ in MDA-MB-231 cells, and compound 4 inhibited the expressions of p-PKCζ in MDA-MB-231 and A549 cells. [ABSTRACT FROM AUTHOR]

A chemical investigation of the endemic relict shrub Tetraena mongolica led to the isolation of four new triterpenes: 11α,12α:13β,28-diepoxyoleanane-3β-yl trans-caffeate (1), 3β-hydroxy-11α,12α-epoxyoleanane-28-al (2), olean-11-en-28-al-3β-yl trans-caffeate (3), and 28-acetoxy-olean-12-en-3β-yl trans-caffeate (4). Their structures were elucidated by extensive spectroscopic methods. [ABSTRACT FROM PUBLISHER]