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The aim of this study was to explore how the mitochondrial alternative oxidase (AOX) pathway alleviates photoinhibition in chilled tomato (Solanum lycopersicum) seedlings. Chilling induced photoinhibition in tomato seedlings despite the increases in thermal energy dissipation and cyclic electron flow around PSI (CEF-PSI). Chilling inhibited the function of PSII and blocked electron transport at the PSII acceptor side, however, it did not affect the oxygen-evolving complex on the donor side of PSII. Upregulation of the AOX pathway protects against photoinhibition by improving PSII function and photosynthetic electron transport in tomato seedlings under chilling stress. The AOX pathway maintained the open state of PSII and the stability of the entire photosynthetic electron transport chain. Moreover, the protective role of the AOX pathway on PSII was more important than that on PSI. However, inhibition of the AOX pathway could be compensated by increasing CEF-PSI activity under chilling stress.

In this paper, the interaction of Orange II and Human Serum Albumin was studied by fluorescence spectroscopy under simulated physiological conditions. The affection of pigment and serum albumin may cause changes in the microenvironment. Fluorescence spectroscopy using synchronous fluorescence can provide a reference for the micro-environment changes in serum albumin. By calculating quenching constantsat different temperatures, its quenching mechanism which is static quenching was determined. The Orange?and HSA binding constants and binding sites were also calculated and the electrostatic force of Orange? with HSA was determined according to the thermodynamic formula. According to the Forster theory, the energy transfer efficiency and biding distance of orange? between HSA were measured and the energytransfer quenching mechanism by the energy transfer was elaborated. Further application of UV absorption spectroscopy to study the mechanism of action and the conclusion of orange? fluorescence spectra are consistent with the HSA.

Manganese (Mn) excess is a major abiotic stress for plant growth. In the present study, we investigated the effects of Mn on photosynthesis in Ligustrum lucidum and Melia azedarach leaves using chlorophyll fluorescence transients. Both plant species were exposed to two Mn concentrations (0.5 and 1 mmol) for 10 and 30 d. Results showed that excess Mn significantly inhibited photosynthesis. With the increase of Mn concentration and stress time, the inhibition was more serious. Mn stress impaired PSII at the donor and the acceptor side by damaging the oxygen-evolving complex and limiting electron transport downstream of QA in both trees. A significant decline in 820 nm reflection curve absorption was observed in M. azedarach, suggesting that the oxidization-reduction reactions in PSI were inhibited but this phenomenon was not observed in L. lucidum. Therefore, excess Mn impaired the whole electron transport chain associated with inactive PSII reaction centers in Ligustrum lucidum and inhibited oxidization-reduction reactions in PSI in M. azedarach.

This study investigated the effects of dietary Arginine (Arg) on performance, intestinal antioxidative capacity, immunity, and gut microbiota in Chinese yellow-feathered chickens. One thousand two hundred 1-day-old female Qingyuan partridge chickens were randomly assigned to 5 groups with 6 replicates of 40 birds each. Chickens were fed diets with 5 levels of total Arg (8.5, 9.7, 10.9, 12.1, and 13.3 g/kg) without antibiotics for 30 d. The ADFI, ADG, and feed conversion ratio were improved with dietary Arg levels (P

The influence of Pb and Zn on chlorophyll (Chl) fluorescence and plant growth of one-year-old Koelreuteria paniculata and Zelkova schneideriana young plants was investigated. Pb and Zn contents in plant organs were measured. The results showed Pb and Zn stress decreased photochemical quenching and quantum efficiency of PSII, but increased energy dissipation in the tested plants. At the same time, maximum net photosynthetic rate, maximum quantum use efficiency, and organ biomass were reduced. Under the same concentration of heavy metals, the damage induced by Zn toxicity was more serious than that of Pb. Pb was less accumulated in leaves, with a mild effect on photosynthesis. Zn was mostly accumulated in leaves and strongly disturbed chloroplast functioning and affected photosynthesis. Pb and Zn had different pathway to influence biomass production, and both tested plants might use different mechanisms of action for heavy metal stress resistance.

In order to predict the rock rupture and instability, acoustic emission signals of natural sandstones and hydrous sandstones are analyzed through the Fast Fourier Transform and the Welch method. It is found that the acoustic emission signals of the hydrous sandstones have narrower range of frequency spectrum and lower average dominant frequencies than the natural sandstones. The dominant frequencies of the acoustic emission signals of the hydrous sandstones reduce more dramatically. In addition, two types of Welch power spectrum of the acoustic emission signals in terms of the shape are presented in this paper, which are named Type A and Type B. The Type B Welch power spectrum emerges when the acoustic emission occurs frequently, in which a disaster tends to appear. Time baselines are selected when relative stronger cracks and crack coalescence happens. We find that the greater signals energy at the time baseline, the higher probability of occurrence of Type B spectrum appears before the time baseline. Also, the probabilities of Type B before the corresponding the baseline time of rock last rupture in hydrous sandstones are higher than that of natural sandstones.

Nanometer minerals as new additives can improve the property of the cement-stabilized soil through some previous researches. Nano-CaO, which has rarely been attempted in admixtures of cemented soft clays for now, was mixed into Tianjin soft clay combined with cement. The unconfined compression tests were carried out to find out the mechanical property of the cemented soil after cured for appropriate days. Additionally the test results were compared with the cemented soil containing other nanometer minerals to clarify the reinforcement effect furthermore. The results show that the strength and the brittleness of cemented soil increases first and then decreases, and the deformation modulus has opposite variation trend with the content of nano-CaO. Compared with other nanometer minerals, the reinforcing effect is similar to nanometer aluminium powder. It can be concluded that if the minerals could improve the strength originally in chemistry, the nanometer treatment can upgrade the chemical reactivity, and improve the strength of cemented soil.

Hoek-Brown criterion is widely used to predict rock strength and analyze stability. Convert the H-B formula to find the relationship between the normal stress sn and shear stress t of the sliding surface. Combined with the H-B criterion, gives a formula Fs to solve the safety factor. The research shows that the Fs is associated with H-B constants mi, geological strength index GSI, disturbance factor D, slice parameter ai , ration of normal stress and saturated single axis compressive strength Sri. Through building rock slope model, to analyze the safety factor Fs at different ranges of parameters. Compared with the results of Swedish slice method, Janbu method, Bishop method and M-P method, it displayed the new algorithm’s rationality and limitations .Finally verifying the applicability of the new algorithm’s through the engineering example.