Search

Allopatric divergence is often initiated by geological uplift and restriction to sky‐islands, climate oscillations, or river capture. However, it can be difficult to establish which mechanism was the most likely to generate the current phylogeographical structure of a species. Recently, genomic data in conjunction with a model testing framework have been applied to address this issue in animals. To test whether such an approach is also likely to be successful in plants, we used population genomic data of the Rheum palmatum complex from the Eastern Asiatic Region, in conjunction with biogeographical reconstruction and demographic model selection, to identify the potential mechanism(s) which have led to the current level of divergence. Our results indicate that the R. palmatum complex originated in the central Hengduan Mts and possibly in regions further east, and then dispersed westward and eastward resulting in genetically distinct lineages. Populations are likely to have diverged in refugia during climate oscillations followed by subsequent expansion and secondary contact. However, model simulations within the western lineage of the R. palmatum complex cannot reject a restriction to sky‐islands as a possible mechanism of diversification due to the genetically ambiguous position of one population. This highlights that genetically mixed populations might introduce ambiguity regarding the best diversification model in some cases. Although it might be possible to resolve this ambiguity using other data, sometimes this could prove to be difficult in complex biogeographical areas. [ABSTRACT FROM AUTHOR]

Aims: Fargesia decurvata is closely allied with F. dracocephala and differs in 5 major characters (i.e. the culm sheath blade base shape, the width of the culm sheath blade base, the auricle shape, and the lower surface of leaf blade) in Fargesia. It is difficult to distinguish these two species because of existing of transitional statements of characters. The aims of this paper are to (i) investigate whether the variation of the characters is continuous or not; (ii) reveal whether the publishment of F. dracocephala was the result of discontinuous sampling of F. decurvata or not. Methods: Ten populations of F. decurvata and F. dracocephala were investigated in their entire distribution (including type localities). The statements of 5 major characters were measured from 693 annual and 693 perennial culms of 231 individuals in 10 populations, and analyzed at population, individual and culm levels. UPGMA cluster analysis was carried out based on 29 characters from 10 populations of F. decurvata and F. dracocephala and 2 populations of F. qinlingensis as outgroup. The ITS sequences were also sequenced and analyzed. Important Findings: Five major characters exhibited great variation not only at population level, but at individual level within a population, even the culm level within an individual and in different parts of the same culm. Cluster analyses showed that 10 populations of F. decurvata and F. dracocephala were not divided into two species, but they were well separated with outgroup. There was no difference in floral organ between F. decurvata and F. dracocephala. MP and NJ trees based on ITS sequences showed the same results with the cluster analysis on morphological characters. All the facts indicated that the publishment of F. dracocephala was the result of discontinuous sampling of F. decurvata, and F. dracocephala should be treated as the synonym of F. decurvata. [ABSTRACT FROM AUTHOR]

At the ambient condition, the simple self-assembly between ZnI, KI, and dabco in acidic HO/CHOH solution produced a tetranuclear iodine cluster with diprotonated dabco as the cation [Hdabco](I) (dabco = 1,4-diazabicyclo[2,2,2]octane) 1. But the same precursors reacted under the solvothermal condition, producing a chained iodine cluster polymer with dedabco as the cation [dedabco](I) (dedabco = N, N′-diethyl-1,4-diazabicyclo[2,2,2]octane) 2. Note that dedabco originated from the solvothermal in situ N-alkylation of dabco with CHOH solvent in acidic KI solution. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The technology of statically and continuously aerobic fermentation of composting garbage stored in cellar has been widely used for waste treatment. In this study, through establishing a water balancing system, we have systematically studied the effects of water content on this whole fermentation technology. The resulted fermentation from using this technology has the characteristics of being technologically simpler, having faster heat exchange rate, and larger quantity of vapor evaporation. In this study, the fermentation temperature was held at about 65 °C, and water content at 45% - 55%, which helps the decomposition of organic materials and leads to the completion of garbage composting in 40 to 50 d. The water content of ferment from the first aerobic fermentation should be under 35%, which gives high efficiency of automatic mechanical separation (filtration), normally at 90 - 95%, and decreases the volume of garbage at about 50% - 60%. The water content of ferment materials should be controlled at 25% - 30% for second fermentation. This increases the efficiency of mechanical removal of solid materials (broken stones and glass, etc.) and decreases them to 0.8% in the organic materials. The second garbage static state aerobic fermentation can utilize water drained out from the garbage to augment the water supply. Therefore, the resources can be recycled for reutilization and zero wastewater discharge can become true. [ABSTRACT FROM AUTHOR]

This paper introduces a technique for determining of anions in leaching solution of municipal solid wastes by using ion chromatography. Disturbing system analysis of complicated composition was avoided. Results show that the determining method is simpler, quicker, and more accurate. The limits of detection for Cl-, NO2-, NO3- PO43- and SO42- were 0.18, 0.45, 0.67, 1.02 and 0.85 mg/L, respectively. In addition, the recoveries were between 95.85% and 106.5%. The optimum condition is 10 mmol/L of N2CO3 in fluent at a flow rate of 1.0 mL/min. [ABSTRACT FROM AUTHOR]

The complete chloroplast genome of the medicinal plantRheum palmatumL. (Polygonaceae) has been reconstructed from the whole-genome Illumina sequencing data. The genome is 161 541 bp in length, and exhibits a typical quadripartite structure of the large (LSC, 86 518 bp) and small (SSC, 13 111 bp) single-copy regions, separated by a pair of inverted repeats (IRs, 30 956 bp each). The chloroplast genome contains 131 genes, including 84 protein-coding genes (78 PCG species), eight ribosomal RNA genes (four rRNA species) and 37 transfer RNA genes (28 tRNA species). Phylogenetic tree based on the maximum parsimony (MP) analysis of 65 chloroplast protein-coding genes for 13 taxa demonstrated a close relationship betweenR. palmatumandFagopyrum esculentumsubsp.ancestralein Polygonaceae. [ABSTRACT FROM AUTHOR]

Objective: To predict the distribution patterns of the original plants of Rhei Radix et Rhizoma current and in future in China under climate change., Methods: A maximum entropy modeling and variety of climate change scenarios were employed to predict its current and future distribution ranges in China., Results: The resultant models exhibited excellent predictive power. The current suitable habitats for original plants of Rhei Radix et Rhizoma totaled 84. 20 x 10(4) km2 accounting for 8. 77% of the total area of China; 57. 05% of its current suitable habitats(i. e. low impact areas) would be relatively lowly impacted by the climate change. Compared with its current distribution pattern,its distribution ranges during 2020s, 2030s, 2040s, 2050, 2060s, 2070s and 2080s would be shrunk to some extent. However, the moderately suitable area would be expanded to a certain degree., Conclusion: Climate change has a negative impact on the total area and the habitat suitability for the original plants of Rhei Radix et Rhizoma.