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Scientific understanding of biotic effects on the water trophic level is lacking for urban lakes during algal bloom development stage. Based on the Illumina MiSeq sequencing, quantitative polymerase chain reaction (PCR), and multiple statistical analyses, we estimated distribution patterns and ecological roles of planktonic bacteria and eukaryotes in urban lakes during algal bloom development stage (i.e., April, May, and June). Cyanobacteria and Chlorophyta mainly dominated algal blooms. Bacteria exhibited significantly higher absolute abundance and community diversity than eukaryotes, whereas abundance and diversity of eukaryotic rather than bacterial community relate closely to the water trophic level. Multinutrient cycling (MNC) index was significantly correlated with eukaryotic diversity rather than bacterial diversity. Stronger species replacement, broader environmental breadth, and stronger phylogenetic signal were found for eukaryotic community than for bacterial community. In contrast, bacterial community displayed stronger community stability and environmental constraint than eukaryotic community. Stochastic and differentiating processes contributed more to community assemblies of bacteria and eukaryotes. Our results emphasized that a strong linkage between planktonic diversity and MNC ensured a close relationship between planktonic diversity and the water trophic level of urban lakes. Our findings could be useful to guide the formulation and implementation of environmental lake protection measures. [ABSTRACT FROM AUTHOR]

Traditionally, the studies on the thermal environment effects of urban land use mainly use statistical analysis, which cannot fundamentally reflect the internal spatial correlation between urban land use and thermal environmental effects. This study introduces the method of fractal theory to this research area and builds a radius dimension to quantitatively describe the characteristics of the spatial pattern of the land use change from the center of the heat island effect to the surroundmg low-temperature radiation process, taking Wuhan as a case study. The results show that: the radius dimension of cropland, forest, water, bare land and built-up area from large to small is 2.343, 2.333, 2.218, 2.304 and 1.715 respectively, indicating that built--up areas has positive effects on urban thermal environment, while forest, cropland and waters have negative effects on urban thermal environment and that of bare land is not obvious. It can be concluded according to our study that the radius dimensíon can effecively distinguish the gathering or mitigating effects of vaious urban land use spatial structure on thermal environmental. Therefore, the results of this study can provide scientific guidance for the government to reduce the extant and degree of urban heat island effect by urban land use planning. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the effect of short enamel etching time on bonding strength., Methods: 80 healthy premolars were randomly divided into two equal groups, one was etched for 15 seconds, the other for 60 seconds, after normally bonding Edgewise brackets, the tooth specimen was stored in water at room temperature for 24 hours. An MTS NEW810 100KN testing machine was used to examine the shear force., Results: Although the bonding strength for 15 seconds etching time was weaker than that for 60 seconds, the means of the bonding strength in 15 seconds group reached 5.8625 MPa., Conclusion: Etching for 15 seconds could provide enough bond strength for orthodontic practice. Furthermore, the adhesive remained on tooth after debonding was less by comparison with 60 seconds etching group, therefore brackets could be removed easily and the work efficiency could be increased in clinic by means of 15 seconds etching time.