Genetic architecture of ecological divergence between Oryza rufipogon and Oryza nivara.

Ecological divergence due to habitat difference plays a prominent role in the formation of new species, but the genetic architecture during ecological speciation and the mechanism underlying phenotypic divergence remain less understood. Two wild ancestors of rice (Oryza rufipogon and Oryza nivara) are a progenitor-derivative species pair with ecological divergence and provide a unique system for studying ecological adaptation/speciation. Here, we constructed a high-resolution linkage map and conducted a quantitative trait locus (QTL) analysis of 19 phenotypic traits using an F2 population generated from a cross between the two Oryza species. We identified 113 QTLs associated with interspecific divergence of 16 quantitative traits, with effect sizes ranging from 1.61% to 34.1% in terms of the percentage of variation explained (PVE). The distribution of effect sizes of QTLs followed a negative exponential, suggesting that a few genes of large effect and many genes of small effect were responsible for the phenotypic divergence. We observed 18 clusters of QTLs (QTL hotspots) on 11 chromosomes, significantly more than that expected by chance, demonstrating the importance of coinheritance of loci/genes in ecological adaptation/speciation. Analysis of effect direction and v-test statistics revealed that interspecific differentiation of most traits was driven by divergent natural selection, supporting the argument that ecological adaptation/speciation would proceed rapidly under coordinated selection on multiple traits. Our findings provide new insights into the understanding of genetic architecture of ecological adaptation and speciation in plants and help effective manipulation of specific genes or gene cluster in rice breeding.

Exfoliation of a Two-Dimensional Metal-Organic Framework for Enhanced Photocatalytic CO2 Reduction.

A two-dimensional metal-organic framework, FICN-12, was constructed from tris[4-(1H-pyrazole-4-yl)phenyl]amine (H3TPPA) ligands and Ni2 secondary building units. The triphenylamine moiety in the H3TPPA ligand readily absorbs UV-visible photons and sensitizes the Ni center to drive photocatalytic CO2 reduction. FICN-12 can be exfoliated into monolayer and few-layer nanosheets with a "top-down" approach, which exposes more catalytic sites and increases its catalytic activity. As a result, the nanosheets (FICN-12-MONs) showed photocatalytic CO and CH4 production rates of 121.15 and 12.17 µmol/g/h, respectively, nearly 1.4 times higher than those of bulk FICN-12.

Highly selective cesium(I) capture under acidic conditions by a layered sulfide.

Radiocesium remediation is desirable for ecological protection, human health and sustainable development of nuclear energy. Effective capture of Cs+ from acidic solutions is still challenging, mainly due to the low stability of the adsorbing materials and the competitive adsorption of protons. Herein, the rapid and highly selective capture of Cs+ from strongly acidic solutions is achieved by a robust K+-directed layered metal sulfide KInSnS4 (InSnS-1) that exhibits excellent acid and radiation resistance. InSnS-1 possesses high adsorption capacity for Cs+ and can serve as the stationary phase in ion exchange columns to effectively remove Cs+ from neutral and acidic solutions. The adsorption of Cs+ and H3O+ is monitored by single-crystal structure analysis, and thus the underlying mechanism of selective Cs+ capture from acidic solutions is elucidated at the molecular level.

[Early production of interleukin-17 in airway upon Chlamydia trachomatis infection increases the local secretion of IL-6 and MIP-2].

OBJECTIVE: To evaluate the early interleukin-17 (IL-17) production in airway upon Chlamydia trachomatis infection and its relationship with the secretion of interleukin-6 (IL-6) and macrophage inflammatory protein 2 (MIP-2) in local site. METHODS: In vivo, a murine model of pneumonia induced by intranasal inoculation with Chlamydia trachomatis mouse pneumonitis (MoPn, now classified as a new species C. muridarum) was used for the study. Chlamydial growth in the lung was assessed by inoculating HeLa cell monolayer with lung homogenates followed by enzyme-linked immunosorbent assay (IFA). IL-17, IL-6 and MIP-2 were measured by enzyme-linked immunosorbent assay (ELISA). Mice without infection acted as the control group. In vitro, L929 cells were pretreated with recombinant murine IL-17 (rmIL-17) at a dose ranging from 20, 100 to 500 µg/L for 24 h then infected with MoPn for 24 h. The supernatants were harvested and tested for IL-6 and MIP-2 concentration using ELISA. The cells were assayed for the number of inclusion-forming unit (IFU) by IFA. L929 cells without pretreatment with rmIL-17 but infected with MoPn was the control group. RESULTS: The study showed that in vivo, Chlamydial growth in the lung was found on day 1 after infection, and reached its peak at day 8 (6.49±0.19, lg IFU/lung) with subsequent decline in quantity. IL-17 peaked at 48 h (83.0 ng/L±35.8 ng/L) while IL-6 peaked on day 3 [(3.98±0.04) µg/L], MIP-2 peaked on day 8 [(2.19±0.71) µg/L]. The study showed that in vitro, compared with control group [(55.10±16.54) ng/L for IL-6 production and (13.71±0.84) ng/L for MIP-2], L929 cells pretreated with rmIL-17 at the different concentrations of 20, 100 and 500 µg/L for 24 h then infected with MoPn for 24 h, could significantly increase IL-6 (P <0.01) and MIP-2 secretion (P <0.05). The productions of IL-6 in the supernatants were (531.65±24.40), (629.95±7.71), and (646.51±35.92) ng/L. Meanwhile, the productions of MIP-2 were (107.21±28.40), (181.95±25.51), and (221.90±17.32) ng/L, respectively. RmIL-17 alone had no effect on IL-6 and MIP-2 secretion, and no direct effect on growth of chlamydial inclusion body was demonstrated either. CONCLUSION: IL-17 was produced early in airway upon Chlamydia trachomatis, and rmIL-17could induce IL-6 and MIP-2 production in L929 cells after infection with MoPn. These suggest that an early IL-17 response may play an important role by inducing the secretion of IL-6 and MIP-2 in initiating host defense against infection with Chlamydia trachomatis in the airway.

The Uptake of Hazardous Metal Ions into a High-Nuclearity Cluster-Based Compound with Structural Transformation and Proton Conduction.

The discovery of novel high-nuclearity oxo-clusters considerably promotes the development of cluster science. We report a high-nuclearity oxo-cluster-based compound with acid/alkali-resistance and radiation stabilities, namely, (H3O)7[Cd7Sb24O24(l-tta)9(l-Htta)3(H2O)6]·29H2O (FJSM-CA; l-H4tta = l-tartaric acid), which features a two-dimensionally anionic layer based on the largest Sb-oxo-clusters with 28-metal-ion-core [Cd4Sb24O24]. It is challenging to efficiently capture Sr2+, Ba2+ (analogue of 226Ra), and [UO2]2+ ions from aqueous solutions due to their high water solubility and environmental mobility, while it is unprecedented that a novel Sb-oxo-cluster-based framework material FJSM-CA can efficiently remove these hazardous ions accompanied with intriguing structural transformations. Especially, it shows fast ion-exchange abilities for Sr2+, Ba2+, and [UO2]2+ (reaches equilibrium within 2, 10, and 20 min, respectively) and high exchange capacity (121.91 mg/g), removal rate R (96%), and distribution coefficient KdU (2.46 × 104 mL/g) for uranium. Moreover, the underlying mechanism is clearly revealed, which is attributed to strong electrostatic interactions between exchanged cations and highly negative-charged frameworks and the strong affinity of (COO)- groups for these cations. Proton conduction of the pristine and Sr2+, Ba2+, [UO2]2+-loaded products was investigated. This work highlights the design of new oxo-cluster-based materials for radionuclide remediation and proton conduction performance.

[Relationship between atmospheric particles and rain water chemistry character].

Rain and atmospheric particle samples were collected in the rural area of Taian and Shenzhen in 2007, respectively. Rain sampling was carried out during the precipitation process and several samples were got from the beginning of one precipitation to the end. The chemical character changes during precipitation and the changes of concentration of particles before and after rain were studied in this research to understand the contribution of particles on the rain chemical character and the rain-out effect for particles. The volume-weighted mean pH of rainwater in Taian was 5.97 and the total concentration of ions was 1 187.96 microeq x L(-1). The mass concentration of PM10 in Taian was 131.76 microg/m3 and that of PM2.5 was 103.84 microg/m3. The volume-weighted mean pH of rainwater in Shenzhen was 4.72 and the total concentration of ions was 175.89 microeq x L(-1). The mass concentration of PM10 in Shenzhen was 56.66 microg/m3 and that of PM2.5 was 41.52 microg/m3. During precipitation process pH and ion concentration of rain decrease and it is shown the neutralizing effect happens. The difference between rainwater of Taian and Shenzhen is due to cloud water acidity, atmospheric particles character and atmospheric acid-basic gases concentration. The clean-up effect of Na+ and Ca2+ by rain is high and which of NH4+ and NO3- is low. The clean-up effect for mass concentration, ions concentration and element concentration of particles by rain are significant.