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Protected tomato cultivation is often subjected to low temperature stress in early spring season in north China. While low soil temperature returns slowly then low air temperature and causes damage to development of tomatoes, thereby reducing the growth of tomatoes, which seriously reduces the yield and quality of tomatoes. This study aimed to explore the effect of low root-zone temperature (LRT, i.e., 7 and 13℃) on the photosynthesis, root architecture, mineral use efficiency and aquaporins genes of tomato. Our findings indicated that LRT decreased the photosynthetic capacity accompanying with the reduction of CO 2 assimilation. Meanwhile, a decrease in stomatal density and size occurred under low root-zone temperature. Stomatal conductance tended to reduce, which was unbeneficial to the diffusion of carbon dioxide and thus decreased photosynthesis. And there have the highest enzyme activity, and sucrose content compared to control. Root traits were remarkably affected by environment temperature. LRT delay root development processes and reduce the number and diameters of ducts in root and stem, thereby limiting mineral absorption and transport. Moreover, Under low root-zone temperature, the genes related to the aquaporin and element transport all showed varying degrees of response. Collectively, these results indicate that LRT may reduces the normal physiological activity of shoots by inhibiting the water transport, which inhibits the growth of tomato seedlings. Our research can provide detailed data to clarify the response characteristics of tomato to low root-zone temperature, and provide reference for low root-zone temperature response of tomato in practice. [ABSTRACT FROM AUTHOR]

Vegetable oil phospholipids can be divided into hydratable phospholipids (HP) and non-hydratable phospholipids (NHP). The general process of alkali refining or hydration degumming can remove most of the phospholipids, and the rest is mainly non-hydratable phospholipids. A non-hydratable phospholipid has obvious hydrophobicity, which cannot be completely removed even after 16 times of washing, so the non-hydratable phospholipid is the main research target of vegetable oil degumming. In order to better understand and study the non-hydratable phospholipids, the chemical composition and origin of non-hydratable phospholipids in vegetable oil are discussed. The advantages and disadvantages of these various detection and removal methods are analyzed in this paper. [ABSTRACT FROM AUTHOR]

Transport of particle beams in plasmas is widely employed in fundamental research, industry, and medicine. Due to the high inertia of ion beams, their transport in plasmas is usually assumed to be stable. Here we report the focusing and flapping of intense slab proton beams transporting through large-scale plasmas by using a recently developed kinetic particle-in-cell simulation code. The beam self-focusing effect in the simulation is prominent and agrees well with previous experiments and theories. Moreover, the beam can curve and flap like turbulence as the beam density increases. Simulation and analysis indicate that the self-generated magnetic fields, produced by movement of collisional plasmas, are the dominant driver of such behaviors. By analyzing the spatial growth rate of magnetic energy and energy deposition of injected proton beams, it is found that the focusing and flapping are significantly determined by the injected beam densities and energies. In addition, a remarkable nonlinear beam energy loss is observed. Our research might find application in inertial confinement fusion and also might be of interest to the laboratory astrophysics community. [ABSTRACT FROM AUTHOR]

Modification of surface and bulk properties of solids by irradiation with ion beams is a widely used technique with many applications in material science. In this study, we show that nano-hillocks on CaF2 crystal surfaces can be formed by individual impact of medium energy (3 and 5 MeV) highly charged ions (Xe22+ to Xe30+) as well as swift (kinetic energies between 12 and 58 MeV) heavy xenon ions. For very slow highly charged ions the appearance of hillocks is known to be linked to a threshold in potential energy (Ep) while for swift heavy ions a minimum electronic energy loss per unit length (Se) is necessary. With our results we bridge the gap between these two extreme cases and demonstrate, that with increasing energy deposition via Se the Ep-threshold for hillock production can be lowered substantially. Surprisingly, both mechanisms of energy deposition in the target surface seem to contribute in an additive way, which can be visualized in a phase diagram. We show that the inelastic thermal spike model, originally developed to describe such material modifications for swift heavy ions, can be extended to the case where both kinetic and potential energies are deposited into the surface. [ABSTRACT FROM AUTHOR]

We report on a precision energy loss measurement and theoretical investigation of 100 keV/u helium ions in a hydrogen-discharge plasma. Collision processes of helium ions with protons, free electrons, and hydrogen atoms are ideally suited for benchmarking plasma stopping-power models. Energy loss results of our experiments are significantly higher than the predictions of traditional effective charge models. We obtained good agreement with our data by solving rate equations, where in addition to the ground state, also excited electronic configurations were considered for the projectile ions. Hence, we demonstrate that excited projectile states, resulting from collisions, leading to capture-, ionization-, and radiative-decay processes, play an important role in the stopping process in plasma. [ABSTRACT FROM AUTHOR]