Effects of arbuscular mycorrhizal inoculation and phosphorus supply on the growth and nutrient uptake of Kandelia obovata (Sheue, Liu & Yong) seedlings in autoclaved soil

National Natural Science Foundation of China [2013CB956504, 31170471, 31370516]This study evaluated the interactive effect of arbuscular mycorrhizal fungi (AMF) inoculation and exogenous phosphorus supply on soil phosphotases, plant growth, and nutrient uptake of Kandelia obovata (Sheue, Liu & Yong). We aimed to explore the ecophysiological function of AMF in mangrove wetland ecosystems, and to clarify the possible survival mechanism of mangrove species against nutrient deficiency. K. obovata seedlings with or without AMF inoculation (mixed mangrove AMF), were cultivated for six months in autoclaved sediment medium which was supplemented with KH2PO4 (0, 15, 30, 60, 120 mg kg(-1)). Then the plant growth, nitrogen and phosphorus content, root vitality, AMF colonization and soil phosphatase activity were analyzed. The inoculated AMF successfully infected K. obovata roots, developed intercellular hyphae, arbuscular (Arum-type), and vesicle structures. Arbuscular mycorrhizal fungi colonization ranged from 9.04 to 24.48%, with the highest value observed under 30 and 60 mg kg(-1) P treatments. Soil P supply, in the form of KH2PO4, significantly promoted the height and biomass of K. obovata, enhanced root vitality and P uptake, while partially inhibiting soil acid (ACP) and alkaline phosphotase (ALP) activities. Without enhancing plant height, the biomass, root vitality and P uptake were further increased when inoculated with AMP, and the reduction on ACP and ALP activities were alleviated. Phosphorus supply resulted in the decrease of leaf N-P ratio in K. obovata, and AMF inoculation strengthened the reduction, thus alleviating P limitation in plant growth. Arbuscular mycorrhizal fungi inoculation and adequate P supply (30 mg kg(-1) KH2PO4) enhanced root vitality, maintained soil ACP and ALP activities, increased plant N and P uptake, and resulted in greater biomass of K. obovata. Mutualistic symbiosis with AMF could explain the survival strategies of mangrove plants under a stressed environment (waterlogging and nutrient limitation) from a new perspective. (C) 2013 Elsevier B.V. All rights reserved

A new chemical inhibitor of angiogenesis and tumorigenesis that targets the VEGF signaling pathway upstream of Ras

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Contact Engineering of Molybdenum Ditelluride Field Effect Transistors through Rapid Thermal Annealing

Understanding and engineering the interface between metal and two-dimensional materials are of great importance to the research and development of nanoelectronics. In many cases the interface of metal and 2D materials can dominate the transport behavior of the devices. In this study, we focus on the metal contacts of MoTe₂ (molybdenum ditelluride) FETs (field effect transistors) and demonstrate how to use post-annealing treatment to modulate their transport behaviors in a controlled manner. We have also carried out low temperature and transmission electron microscopy studies to understand the mechanisms behind the prominent effect of the annealing process. Changes in transport properties are presumably due to anti-site defects formed at the metal–MoTe₂ interface under elevated temperature. The study provides more insights into MoTe₂ field effect devices and suggests guidelines for future optimizations