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To understand the relationship of rice quality with nitrogen and phosphorus fertilizers, it is essential to optimize the fertilizer control in the rice field. In the current experiment, two factors, nitrogen and phosphorus, were considered in a split plot design with 9 treatments. Nitrogen (N) was set at N0 (0 kg / hm²), N150 (150 kg / hm²) and N300 (300 kg / hm²), and phosphorus (P) was set at P0 (0 kg / hm²), P120 (120 kg / hm²), and P240 (240 kg / hm²). The results of the current experiment revealed that the correlation coefficients of nitrogen fertilizer with peak viscosity (PKV), breakdown value (BDV) and peak time (PeT) were -0.831, -0.794 and 0.874, respectively. The correlation coefficients of phosphorus fertilizer with hot pasting viscosity (HPV) and cold pasting viscosity (CPV) were -0.719 and -0.888. The intensity and width of diffraction peak at 2 = 15.2°, 18.3°, and 20° in XRD were significantly related to the nitrogen and phosphorus fertilizer in rice field. Based on results it is concluded that increasing nitrogen and phosphorus application could significantly increase the proportion of composite starch grains and improve the density of rice starch. Peak viscosity, BDV, HPV and CPV in Rapid Visco Analysis profiles and diffraction peak at 2 = 15.2°, 18.3° and 20° in XRD are sensitive to N and P regulation, which can be used to guide the regulation of nitrogen and phosphorus in rice field. [ABSTRACT FROM AUTHOR]

Long slender elastic structures, such as railroad tracks, pipelines, and pavements, may experience buckling owing to axial compressive forces developed in them as a result of thermal or other effects, and in many cases these structures can be simplified as a beam on an elastic foundation. This paper presents an investigation of the critical buckling and postbuckling of such an elastic structure on a nonlinear foundation that has softening and restabilizing effects. The method of minimization of the total potential energy of the beam-foundation system is invoked to develop a differential equation of equilibrium and a differential equation of critical buckling (or bifurcation) of the beam. The analysis shows that critical buckling may be in a symmetric or in an antisymmetric mode, depending on the length of the beam, and when the length is extremely large, the two buckling modes are indistinguishable. The equations of the postbuckling equilibrium of the beam are highly nonlinear. To elucidate the response of the beam, a multiple-scale perturbation technique as used in modal analysis and a numerical solution based on a shooting technique are developed. It is shown that the postbuckling equilibrium of the beam has two stages after its critical buckling: a postbuckling localization stage that is unstable, and a subsequent postbuckling snaking stage characterized by a zigzag of the equilibrium configuration, and this snaking stage is dependent on the relative effects of the softening and restabilizing parameters. Comparisons of the perturbation solutions with the results of the numerical formulation show that the former semianalytical technique is accurate in the initial stages of postbuckling during which localization develops, but not in the subsequent snaking stage. The effect of the foundation parameters is also investigated in the paper. [ABSTRACT FROM AUTHOR]

The enzyme C-14 sterol reductase is involved in biosynthesis of brassinosteroids (BR) and sterols, as well as plant development. OsFK1, a member of the sterol biosynthesis pathway located in the endoplasmic reticulum (ER), encodes C-14 sterol reductase. However, there is little research on the function of C-14 sterol reductase in rice. Compared with the wild type, an osfk1 mutant showed dwarf phenotype and premature aging in the second leaf during the trefoil stage, and abnormal development of leaf veins during the tillering stage. The osfk1 mutant showed signs of aberrant PCD, as evidenced by TUNEL staining. This suggested that high ROS buildup caused DNA damage and ROS-mediated cell death in the mutant. The osfk1 mutant also showed decreased chlorophyll content and aberrant chloroplast structure. Sequencing of the osfk1 mutant allele revealed a non-synonymous G to A mutation in the final intron, leading to early termination. Here, we identified the OsFK1 allele, cloned it by Mutmap sequencing, and verified it by complementation. HPLC-MS/MS assays demonstrated that the osfk1 mutation caused lower phytosterol levels. These findings showed that the OsFK1 allele encoding C-14 sterol reductase is involved in phytosterol biosynthesis and mediates normal development of rice plants. [ABSTRACT FROM AUTHOR]

Field frost-thaw deformation tests show that the frost susceptibility of graded aggregate is a major factor contributing to the instability of high speed railway track. This paper is aimed at studying the effect of cement content (0%, 3%, 5%, 7% and 9%) on the mechanical, dry shrinkage behavior and frost heave susceptibility of cement stabilized aggregate (CSA) used for high speed railway roadbed and the strengthening mechanism of cement. An ultrasonic pulse velocity (UPV) technique was employed to continuously and nondestructively monitor the microstructure formation process of CSA. The experimental results show that compressive strength, flexural strength and frost heave resistance property increase with the cement replacement. However, reverse phenomenon is observed in the shrinkage behavior. Based on the UPV development test, the microstructure evolution process of CSA can be clearly identified into three stages. The mechanism of cement can be classified into “filling effect” and “binding effect” and the latter effect is more dominant. The optimum cement content and water to cement ratio (w/c) are estimated to be 5% and 1, respectively. At these value, an efficient compaction, denser structure and reduced frost susceptibility can be simultaneously achieved. In addition, X-ray tomography technology (XCT) was also employed to characterize the microstructure quantitatively. [ABSTRACT FROM AUTHOR]

A stably inherited zebra and semi-dwarf 11 (zsd11) mutant was selected from the Wuyunjing21 mutant library, which was perpendicular to the direction of the main leaf vein and alternated between yellow and green. The zebra phenotype of this mutant appeared at the seedling stage, and increased to the early tillering stage, then gradually weakened as the growth and development reached the late tillering stage to the early booting stage until the leaves completely turned yellow at maturity. In the seedling, tillering and maturation stages, the mutant pigment content was significantly reduced compared to the wild type. Correspondingly, the net photosynthetic rate and maximum photochemical efficiency in the photosynthesis indicators also dropped significantly. After maturation, the plant height, effective panicle number, thousand-grain weight, and the number of secondary branches of the mutant were significantly lower than the wild type. Genetic analysis exhibited that the phenotype is controlled by a pair of recessive nuclear genes. Through MutMap strategy and gene sequencing analysis, the candidate gene encodes carotenoid isomerase on chromosome 11. The first base G of the first intron mutates into A, resulting in the wrong splice recognition site during transcription. Comparative analysis of protein sequences showed that the evolutionary relationship between rice carotenoid isomerase and wheat, corn, and sorghum was very close. [ABSTRACT FROM AUTHOR]

Understanding the influences of rainfall and temperature on soil water and the grain production of winter wheat (Triticum aestivum L.), is of great importance to ensure the sustainability of food production on the Loess Plateau of China. Based on calibration and evaluation, the Environmental Policy Integrated Climate (EPIC) model was employed to determine the response of soil water and winter wheat to rainfall and temperature changing over the last 30 years in different regions. Results showed that (1) the EPIC model simulated soil water content well in 0-2 m soil, with a relative root mean square error (RRMSE) value of 6.0~14.0%, and the mean value of R2 was 0.824, which was similar to the value of ME (0.815); (2) rainfall decreased 13.6-24.9% more from 2001 to 2010 than it did during 1961-2000, while its minimum and maximum temperature increased 1.00-1.55 °C and 0.30-0.84 °C respectively, in comparison with 1961-2000; (3) both the increase of maximum temperature and the decrease of rainfall were harmful to the production of winter wheat. Contrarily, the increase of minimum temperature was beneficial to the production of winter wheat on the Loess Plateau of China. Furthermore, due to rainfall decreasing, the winter wheat yield of Luochuan, Changwu, Yuncheng, and Yan'an decreased by 8.5%, 7.6%, 11.7%, and 12.3%, respectively. Because of the rising of the maximum temperature, winter wheat yield decreased 6.4%, 6.8%, 7.2%, and -3.0%, respectively. On the other hand, the increase of the minimum temperature raised the winter wheat yield of 8.8%, 10.2%, 1.5%, and 12.0%, respectively. Climate change, either precipitation reduction or temperature increase, decreased soil water in the dry land winter wheat field. Therefore, more water-saving technologies are needed to adapt to climate change, to store and use water sources more effectively in semi-arid regions. Though precipitation reduction and maximum temperature increase produced negative impacts on winter wheat yield, the uptrend in minimum temperature is better for increasing the winter wheat yield, which can be used by farmers and governments to adapt to climate change, by adjusting planting time properly. [ABSTRACT FROM AUTHOR]

Background: Accurate intraoperative localization of esophageal lesions is essential for successful surgical resection. We tested whether preoperative endoscopic placement of titanium clips could facilitate intraoperative localization of early-stage esophageal cancer or severe dysplasia. Methods: A prospective randomized clinical trial was performed between May 2012 and July 2014. All enrolled patients received preoperative endoscopy and esophageal endoscopic ultrasound, as well as pathological study on the biopsy specimen, to confirm early stage esophageal cancer or severe dysplasia. One day before the surgical operation, patients in the experimental group received the preoperative endoscopic titanium labeling of esophageal lesions. Then, during the surgical operation, palpitation of titanium clips was used to localize the lesions in these patients. In patients in the control group, palpitation of nodules or esophageal wall mucosal thickening, together with the consideration of the results from preoperative endoscopic and ultrasound studies, was applied to estimate the location of the esophageal lesions. Study outcomes included the proportions of patients having successful intraoperative pre-resection lesion localization, post-esophagectomy lesion visualization, negative upper surgical margin, change of surgical approaches, and positive postoperative pathological diagnosis. Results: A total of 27 patients were enrolled into the study, with 14 in the experimental group and 13 in the control group. Compared to the patients in the control group, a higher proportion of patients in the experimental group had statistically significant successful intraoperative esophageal lesion localization (100 versus 15.3% in the experimental versus control group). Conclusions: Preoperative endoscopic titanium clip placement could facilitate intraoperative localization of early-stage esophageal cancer or severe dysplasia. [ABSTRACT FROM AUTHOR]