Influence of macrobenthos ( Meretrix meretrix Linnaeus ) on erosion‐accretion processes in intertidal flats: A case study from a cultivation zone

The activity of benthic organisms can strongly influence sediment dynamics in anintertidal flat. However, few studies have conducted a quantitative assessment of the effect of benthic organisms on erosion-accretion processes under field conditions. The aim of this study was to quantify the effects of the benthic clam Meretrix meretrix Linnaeus on bed erodibility and sediment erosion- accretion processes in an intertidal flat. Within the cultivation zone atsite A, M. meretrix is present in large numbers (up to 137 individuals/m2). On the other hand, site B is located outside the cultivation zone. At this site, which is only 500 m away from site A alongshore, M. meretrix forms a sparse population with only 3.7 individuals/m2. The results showed that the critical shear stress for erosion, denoted by τce, was 0.22 and 0.32 N/m2 at sites B and A, respectively, and the magnitudes of bed-level change were significantly higher at site A than site B. These results reveal the large effect of M. meretrix on decreasing τce, augmenting the erosion rate when the bed shear stress due to combined currents and waves, denoted by τcw, was higher than τce, and conversely enhancing the accretion rate when τcw < τce. The changes induced in these parameters are likely to have a large impact on model predictions of bed erodibility, sedimentary processes, and morphological evolution. Thus, integrated field measurements of hydrodynamic and bed-level changes, accompanied by simultaneous biological sampling, may help to improve the parameterization of hydro-sedimentary and morphodynamic models for shallow-water environmentsFil: Shi, Benwei. Tongji University; República de China. East China Normal University; República de ChinaFil: Pratolongo, Paula Daniela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Duy, Yongfen. Nanjing Normal University; República de ChinaFil: Li, Jiasheng. Nanjing Normal University; República de ChinaFil: Yang, S.L.. East China Normal University; República de ChinaFil: Wu, Jihua. Fudan Universit. Institute of Biodiversity Science; República de ChinaFil: Xu, Kehui. State University of Louisiana; Estados UnidosFil: Wang, Ya Ping. East China Normal University; República de Chin

Revealing of the Activation Pathway and Cathode Electrolyte Interphase Evolution of Li-Rich 0.5Li2MnO3·0.5LiNi0.3Co0.3Mn0.4O2 Cathode by in Situ Electrochemical Quartz Crystal Microbalance.

The first-cycle behavior of layered Li-rich oxides, including Li2MnO3 activation and cathode electrolyte interphase (CEI) formation, significantly influences their electrochemical performance. However, the Li2MnO3 activation pathway and the CEI formation process are still controversial. Here, the first-cycle properties of xLi2MnO3·(1- x) LiNi0.3Co0.3Mn0.4O2 ( x = 0, 0.5, 1) cathode materials were studied with an in situ electrochemical quartz crystal microbalance (EQCM). The results demonstrate that a synergistic effect between the layered Li2MnO3 and LiNi0.3Co0.3Mn0.4O2 structures can significantly affect the activation pathway of Li1.2Ni0.12Co0.12Mn0.56O2, leading to an extra-high capacity. It is demonstrated that Li2MnO3 activation in Li-rich materials is dominated by electrochemical decomposition (oxygen redox), which is different from the activation process of pure Li2MnO3 governed by chemical decomposition (Li2O evolution). CEI evolution is closely related to Li+ extraction/insertion. The valence state variation of the metal ions (Ni, Co, Mn) in Li-rich materials can promote CEI formation. This study is of significance for understanding and designing Li-rich cathode-based batteries

Proteomic identification of OsCYP2, a rice cyclophilin that confers salt tolerance in rice (Oryza sativa L.) seedlings when overexpressed

<p>Abstract</p> <p>Background</p> <p>High Salinity is a major environmental stress influencing growth and development of rice. Comparative proteomic analysis of hybrid rice shoot proteins from Shanyou 10 seedlings, a salt-tolerant hybrid variety, and Liangyoupeijiu seedlings, a salt-sensitive hybrid variety, was performed to identify new components involved in salt-stress signaling.</p> <p>Results</p> <p>Phenotypic analysis of one protein that was upregulated during salt-induced stress, cyclophilin 2 (OsCYP2), indicated that <it>OsCYP2 </it>transgenic rice seedlings had better tolerance to salt stress than did wild-type seedlings. Interestingly, wild-type seedlings exhibited a marked reduction in maximal photochemical efficiency under salt stress, whereas no such change was observed for <it>OsCYP2</it>-transgenic seedlings. <it>OsCYP2</it>-transgenic seedlings had lower levels of lipid peroxidation products and higher activities of antioxidant enzymes than wild-type seedlings. Spatiotemporal expression analysis of <it>OsCYP2 </it>showed that it could be induced by salt stress in both Shanyou 10 and Liangyoupeijiu seedlings, but Shanyou 10 seedlings showed higher <it>OsCYP2 </it>expression levels. Moreover, circadian rhythm expression of <it>OsCYP2 </it>in Shanyou 10 seedlings occurred earlier than in Liangyoupeijiu seedlings. Treatment with PEG, heat, or ABA induced <it>OsCYP2 </it>expression in Shanyou 10 seedlings but inhibited its expression in Liangyoupeijiu seedlings. Cold stress inhibited <it>OsCYP2 </it>expression in Shanyou 10 and Liangyoupeijiu seedlings. In addition, OsCYP2 was strongly expressed in shoots but rarely in roots in two rice hybrid varieties.</p> <p>Conclusions</p> <p>Together, these data suggest that OsCYP2 may act as a key regulator that controls ROS level by modulating activities of antioxidant enzymes at translation level. OsCYP2 expression is not only induced by salt stress, but also regulated by circadian rhythm. Moreover, OsCYP2 is also likely to act as a key component that is involved in signal pathways of other types of stresses-PEG, heat, cold, or ABA.</p