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Whole genome sequencing for generating SNP data is increasingly used in population genetic studies. However, obtaining genomes for massive numbers of samples is still not within the budgets of many researchers. It is thus imperative to select an appropriate reference genome and sequencing depth to ensure the accuracy of the results for a specific research question, while balancing cost and feasibility. To evaluate the effect of the choice of the reference genome and sequencing depth on downstream analyses, we used five confamilial reference genomes of variable relatedness and three levels of sequencing depth (3.5×, 7.5× and 12×) in a population genomic study on two caddisfly species

Currently, the genus Polypedates comprises 26 species distributed in South, Southeast, and East Asia. Because of their relatively low dispersal capability and intolerance to seawater, this genus is ideal for the study of terrestrial range evolution that extends into the island archipelagos of southeastern Asia. In this study, based on data compiled for Polypedatesfrom previous studies and partial mitochondrial and nuclear genes collected in this study, we performed systematic biogeographical analysis. We confirmed a Sundaland origin for the extant genus and showed northward dispersal into mainland Southeast Asia and Asia, which coincided with the timing of paleoclimatic change from the Oligocene to Middle Miocene. Climate fluctuations had a profound impact on species diversification within the genus Polypedates. Furthermore, the Red River did not mediate species exchange between Southeast Asia and mainland Asia until the end of the Miocene, with the sudden onset of northward dispersal in several clades independently at that time. Alternatively, the lineage of widespread insular P. leucomystaxstrongly supports the hypothesis of terrestrial connection between island archipelagos of Southeast Asia during the Mid-Pleistocene paleoclimate fluctuations. Our biogeographical analysis also supports the recent introduction of P. leucomystax to the Philippines and Ryukyus, as previously suggested.

BackgroundThe yield of commercially harvested “vegetable caterpillar” Ophiocordyceps sinensis has dramatically plummeted in the last few decades, while market demand has increased. Besides controlling the obvious overexploitation of this species, understanding how edaphic factors influence this system may improve the chances of successful cultivation and thus support the conservation of O. sinensis in the wild. Our study investigates how the presence/absence and the quality of O. sinensis may be linked to a series of edaphic factors pertinent to its microhabitat, including enzyme activity, nutrients, moisture, pH and nematode population. In order to provide a preliminary hypothesis on the relationships among edaphic factors and their influence on O. sinensis, we performed a principal component analysis and structural equation modelling despite limited replication. ResultsSoil samples containing O. sinensis were more moist and contained a higher concentration of nutrients and enzyme activity than control samples collected nearby, where the species was absent. Preliminary analyses indicated that enzyme activity may be crucial and appeared to be affected by a number of other soil factors. We found that O. sinensis would occupy microhabitats with a relatively higher soil fertility and a more persistent enzyme activity, where the values of total nitrogen and catalase are especially important. Otherwise, with the exception of organic matter and enzyme activity, mean values did not suggest any other factors potentially corresponding to a better quality of O. sinensis.ConclusionsBased on these preliminary findings and a further literature review, we formulated the first integrative hypothesis (network of interactions) on how soil factors may influence each other and O. sinensis. Finally, we indicate how this hypothesis may be tested in the future, in order to increase the chances for successful cultivation and thus promote the conservation and sustainable harvesting of O. sinensis.

Currently, the genus Polypedates comprises 26 species distributed in South, Southeast, and East Asia. Because of their relatively low dispersal capability and intolerance to seawater, this genus is ideal for the study of terrestrial range evolution that extends into the island archipelagos of southeastern Asia. In this study, based on data compiled for Polypedatesfrom previous studies and partial mitochondrial and nuclear genes collected in this study, we performed systematic biogeographical analysis. We confirmed a Sundaland origin for the extant genus and showed northward dispersal into mainland Southeast Asia and Asia, which coincided with the timing of paleoclimatic change from the Oligocene to Middle Miocene. Climate fluctuations had a profound impact on species diversification within the genus Polypedates. Furthermore, the Red River did not mediate species exchange between Southeast Asia and mainland Asia until the end of the Miocene, with the sudden onset of northward dispersal in several clades independently at that time. Alternatively, the lineage of widespread insular P. leucomystaxstrongly supports the hypothesis of terrestrial connection between island archipelagos of Southeast Asia during the Mid-Pleistocene paleoclimate fluctuations. Our biogeographical analysis also supports the recent introduction of P. leucomystax to the Philippines and Ryukyus, as previously suggested.

Currently, the genus Polypedates comprises 26 species distributed in South, Southeast, and East Asia. Because of their relatively low dispersal capability and intolerance to seawater, this genus is ideal for the study of terrestrial range evolution that extends into the island archipelagos of southeastern Asia. In this study, based on data compiled for Polypedates from previous studies and partial mitochondrial and nuclear genes collected in this study, we performed systematic biogeographical analysis. We confirmed a Sundaland origin for the extant genus and showed northward dispersal into mainland Southeast Asia and Asia, which coincided with the timing of paleoclimatic change from the Oligocene to Middle Miocene. Climate fluctuations had a profound impact on species diversification within the genus Polypedates. Furthermore, the Red River did not mediate species exchange between Southeast Asia and mainland Asia until the end of the Miocene, with the sudden onset of northward dispersal in several clades independently at that time. Alternatively, the lineage of widespread insular P. leucomystax strongly supports the hypothesis of terrestrial connection between island archipelagos of Southeast Asia during the Mid-Pleistocene paleoclimate fluctuations. Our biogeographical analysis also supports the recent introduction of P. leucomystax to the Philippines and Ryukyus, as previously suggested.

Background The genus Polypedates has a wide range, covering eastern India, Southeast Asia, South China, and eastward to the Philippines and Japan. Because of their poor marine dispersal capabilities, they are ideal organisms to infer geological and environmental history. Based on a large amount of data set for the genus Polypedates that we compiled from a dozen previous studies and partial mitochondrial and nuclear genes collected in this study, we calculated thorough statistical biogeographical analyses. Results We can confirm the genus’ Sundaland origin and showed its northward dispersal into Indochina and mainland Asia from the Late Oligocene to Middle Miocene. And the Red River did not mediate species exchange between Southeast Asia and mainland Asia until the end of the Miocene, with a sudden onset of northward dispersal in several clades independently at that time. The widespread P. leucomystax dispersed from Indochinese Peninsula southward to Malay Peninsula, Sumatra and Java, afterwards to Borneo and Sulawesi. Our biogeographical analysis supports the view of a recent introduction of P. leucomystax to the Philippines and the Ryukyus as previously suggested. Conclusion Our results indicate that climate fluctuations have a profound impact on species diversification within genus Polypedates . The Red River did not act as a diffuse filter barrier for the species exchange until the end of the Miocene. And the widespread P. leucomystax dispersed in Southwest possibly facilitated by the freshwater plume of the emergent South Sunda River System.

We carried out photopolymerization by [2 + 2] dimerization of a photoreactive guest molecule in the channels of a photoreactive porous coordination polymer. The photoreactions of the guest and two host ligands were monitored by single-crystal X-ray crystallography, providing snapshots of the interplay between the reactive centers. By correlating the structures of these three photocenters, a strong synergism was discovered among three reaction (quasi)equilibria and three types of photochemical reactions (isomerization, dimerization, and polymerization). This result indicates a strong coupling and feedback mechanism among the photocenters moderated by the coordination backbone.

Activity-guided fractionation for complement inhibitors led to the isolation of 24 known compounds from Anchusa italica. Chemical types include eight megastigmane compounds, five triterpenoid compounds, five lignan compounds, three flavonoid compounds, two alkaloid compounds and one phenthyl alcohol compound. Among which, a lignan (medioresinol), an alkaloid (5-hydroxypyrrolidin-2-one) and a flavonoid (5-hydroxyl-3', 4', 6, 7-tetramethoxy flavone) exhibited better anticomplementary effects with CH50 values ranging from 0.07 to 0.82 mM, which are plausible candidates for developing potent anticomplementary agents.

Twelve coordination compounds of Mn2+, Fe2+, Co2+, Ni2+, Cu2+ and Zn2+, with mixed organic ligands 5-methylisophthalic acid, 2,2′-bipyridine or phenanthroline, have been hydrothermally synthesised and characterised. The magnetic properties of the Mn2+, Co2+, Ni2+ and Cu2+ compounds have been investigated. Structure analysis shows that the assemblies with a bridging ligand possessing a smaller methyl group (compared to the tert-butyl group) afford coordination compounds containing multinuclear metal centres and structures of higher dimension. The result shows that the structures and properties of the metal–organic materials can be finely tuned by the substituent on the organic bridging ligands.

To find a best synthesis method of diethyl N-[p-(methylamino)benzoyl]-L-glutamate(1).Using diethyl N-(p- aminobenzoyl)-L-glutamate (2) as a starting material via a one-pot process of benzylation and methylation, the diethyl N-[p-(methylamino)benzoyl ]-L-glutamate (3) is prepared in high yield. Then compound 1 was conveniently obtained from debenzylation of compound 3 by Pd/C.The target compound was obtained through 2-step reaction in 88% overall yield in only 6 h, and its structure was identified by 1HNMR and MS.It is a convenient and efficient method of preparation of diethyl N-[p-(methylamino)benzoyl]-L-glutamate.