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In the present paper, the Monte Carlo simulation method is investigated for the random vibration analysis of the large-scale nonlinear systems that is subjected to non-stationary random excitations. Motion equations of nonlinear systems are first transformed into the form of state equations by introducing the concept of equivalent excitations and solved by the precise time integration method. An explicit iteration expression is then deduced for dynamic response analysis of nonlinear systems. Based on the above explicit iteration expression, the computational cost for deterministic dynamic analysis of nonlinear systems can be significantly reduced, and therefore Monte Carlo simulation can be readily conducted using the explicit iteration expression as the tool for sample tests. Statistical properties of the non-stationary random response of a nonlinear system, including the evolutionary probability density function of the response, can be obtained with the proposed method. Numerical examples show that the present approach is of high accuracy and efficiency and is suitable for random vibration analysis of large-scale nonlinear systems. [ABSTRACT FROM AUTHOR]

BACKGROUND Phosphorus (P) loss from cropland is accelerating the eutrophication of waters around the world such as the Three Gorges Reservoir ( TGR) in China. We investigated whether purple paddy soil under long-term P applications was a major source of P efflux to the TGR. RESULTS Substantial surplus P in the plough layer (0-20 cm) was evident after 15-year P applications. Available P (Olsen-P) in the plough layer ranged from 1.9 to 42.4 mg kg−1 and some of which will exceed the threshold of 30 mg kg−1 for environmental concern within 7 years of P application (inorganic NPK with or without organic fertiliser). Between 30 and 70% of Olsen-P was leached out of the 0-30 cm soil layer. Surplus P resulted in high P concentrations in the surface water during the rice cropping season, and these concentrations exceeded those in most waters of the TGR and exceeded the critical level for eutrophication (0.1 mg L−1) during the first 10 days after rice planting. Furthermore, total P in run-off due to rainfall events exceeded the level for eutrophication, with a total loss of 43.2-147.9 g P ha−1 depending on the fertilisation. CONCLUSION Current agronomic P management in purple paddy soil is environmentally unsustainable in terms of the adverse impact on surface water quality. Integrated P management practices are urgently required to optimise crop yield while minimising P loss in order to protect surface water quality in the TGR region. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The present study was performed to investigate the effect of nitric oxide ( NO) fumigation on fruit ripening of harvested ' Sui you 2' Carica papayas in relation to postharvest quality and soluble sugar content. Fruits were fumigated for 3 h with 60 μL/L NO and stored at 20C and 75% relative humidity for 20 days. NO treatment effectively suppressed ethylene formation and respiratory rate ( CO2 levels), reduced weight loss, maintained firmness and delayed changes in peel color and soluble solid contents during 20 days of storage. The level of vitamin C initially increased and then declined slightly during storage at a slower rate in the NO-treated fruits than in controls. Exposure to 60 μL/L NO resulted in significant decreases in fructose and sucrose content. Glucose content in NO-treated fruits was higher than that in controls. Our results indicate that NO gas can be used to prolong fruit storage life and delay changes in soluble sugar content in papaya fruit. Practical Applications Nitric oxide ( NO) gas, a highly reactive free radical, is being studied to resist vegetative stress and senescence of horticultural products. NO was initially regarded as an environmental pollutant, but since 1996, when emission of NO from plants was reported by Leshem and Haramaty, it has drawn much worldwide attention. The present study was performed to investigate the effect of NO fumigation on fruit ripening of harvested 'Sui you 2' Carica papaya in relation to the postharvest quality and content of soluble sugars. Our results indicate that NO gas can be potentially applied for prolonging the storage life and delaying soluble sugar change of papaya fruit. [ABSTRACT FROM AUTHOR]

Taking rice variety Shennong 265 as test material, a hydroponic experiment was conducted to investigate the effects of Fe (0, 0. 1, 0. 25 and 0. 5 mmol Fe2+·L-1) and Cd (0, 0. 1 and 1. 0 umol Cd2+ ·L-1 ) on the lipid peroxidation and antioxidative enzyme activities of rice plant. When the Fe was supplied alone, the shoot and root dry mass decreased significantly, but this phe-nomenon would not occur when the Cd was applied simultaneously. Applying Cd alone decreased the root malondialdehyde (MDA) and soluble protein contents, but applying Fe simultaneously alleviated the negative effects of Cd. Applying Fe decreased the Cd concentrations in shoots and roots, whereas applying Cd decreased the shoot and root Fe concentrations, indicating an obvious antagonistic interaction between Fe and Cd. The interaction of high concentration (1. 0 μmol·L-1) Cd with Fe increased the root MDA and soluble protein contents, and decreased the root superoxide dismutase (SOD) and catalase (CAT) activities. These results indicated that applying definite amount of exogenous Fe could decrease the Cd accumulation in rice under low Cd stress, whereas high Cd stress would decrease the Fe absorption by rice and induce the lipid peroxidation in rice plant. [ABSTRACT FROM AUTHOR]

ABSTRACT MYC2, a basic helix-loop-helix (bHLH) transcription factor, is a key regulator in the activation of jasmonate (JA) response. However, the molecular details of MYC2 involving in methyl jasmonate (MeJA)-induced chilling tolerance of fruit remain largely unclear. In the present work, two MYC2 genes, MaMYC2a and MaMYC2b, and one homolog of the inducer of the C-repeat-binding factor (CBF) gene, MaICE1 were isolated and characterized from banana fruit. MaMYC2s and MaICE1 were found to be all localized in the nucleus. In addition, the proline-rich domain (PRD) and the acidic domain (AD) in the N-terminus were important for the transcriptional activation of MaMYC2 in yeast cells. Unlike MaICE1's constitutive expression, MaMYC2a and MaMYC2b were induced rapidly following MeJA treatment during cold storage. Moreover, protein-protein interaction analysis confirmed that MaMYC2s interacted with MaICE1. The expression of ICE-CBF cold-responsive pathway genes including MaCBF1, MaCBF2, MaCOR1, MaKIN2, MaRD2 and MaRD5 was also significantly induced by MeJA. Taken together, our work provides strong evidence that MaMYC2 is involved in MeJA-induced chilling tolerance in banana fruit through physically interacting and likely functionally coordinating with MaICE1, revealing a novel mechanism for ICE1 in response to cold stress as well as during development of induced chilling tolerance. [ABSTRACT FROM AUTHOR]

A strategy of feedback control optimization of stochastic dynamic systems via stationary response is proposed. First, the control system subjected to wide-band random excitations is formulated based on the stochastic averaging method for quasi-integrable Hamiltonian systems and then transformed into Ito stochastic differential equation. Second, the averaged Ito stochastic differential equation for the system is derived and the stationary solution of the Fokker-Plank-Kolmogorov equation associated with the averaged Ito equation is obtained. Third, the mean square value of the control force and the Hamiltonian function are combined handily as the performance index of the system and the optimal control force is obtained. Finally, two examples are worked out in detail to illustrate the application and the effectiveness of the proposed strategy. [ABSTRACT FROM AUTHOR]

The experiment was conducted to explore the effect of the metabolites of Lactobacillus plantarum on the growth performance and intestinal health of Yellow-feathered broilers. A total of 828 one-day-old Yellow-feathered broilers were randomly divided into two groups, with six replicates in each group and sixty-nine broilers in each replicate. The broilers in the control group were fed with basal diet, and the experimental group added 300 mg/kg the metabolites of Lactobacillus plantarum into the basal diet. The experiment lasted for 63 days. The results showed that compared to the control group, F/G of Yellow-feathered broilers in 1-21 days of the experimental group was decreased by 1.8% (P<0.05), the gene expression of TNF-α, IL-1β, and IL-6 of jejunum were decreased by 50.5%, 72.6%, and 23.1%, respectively (P<0.05), and the score of dung morphology was decreased by 40.3% (P<0.05). The ADG of Yellow-feathered broilers in 22-63 days, the VH in jejunum and ileum, the VH/CD in ileum, and the microbial community abundance of Butyrate-producing bacteria in the experimental group were increased. The study indicates that the metabolites of Lactobacillus plantarum combined with the basal diet can improve the growth performance and intestinal health, and then improve the economic benefit. [ABSTRACT FROM AUTHOR]

• Parental conflict is an important risk factor for adolescents' cyberbullying. • The relationship between parental conflict and cyberbullying is partially mediated by social anxiety. • Perceived social support moderates the direct and indirect associations between parental conflict and adolescents' cyberbullying.. The current study investigated the relationship between parental conflict and cyberbullying, while examining the mediating role of social anxiety and the moderating role of perceived social support. A total of 1,187 Chinese adolescents (11–18 years of age (17.9% 7th graders, 27.1% 8th graders, 31.5% 10th graders, 23.5% 11th graders; M age = 14.51, SD age = 1.59, 45% male) completed a cross-sectional questionnaire to test the relationships between parental conflict, social anxiety, perceived social support and cyberbullying. Our results suggest that parental conflict is positively correlated with adolescent cyberbullying, and that the association is partially mediated by social anxiety. Additionally, perceived social support moderates the both the direct and indirect associations between parental conflict and adolescent cyberbullying. In particular, the association between parental conflict and adolescent cyberbullying, as well as the relationship between social anxiety and adolescent cyberbullying are weaker among adolescents with high levels of perceived social support. In contrast, the association between parental conflict and adolescent social anxiety is stronger in adolescents with high levels of perceived social support. [ABSTRACT FROM AUTHOR]