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Galeaspida is an endemic clade of jawless stem-gnathostomes (‘ostracoderms’), known exclusively from the Silurian and Devonian of China and Vietnam. Among galeaspids, the family Sanqiaspidae is of particular interest for providing the first information on the galeaspid trunk and caudal fin; however, the cranial morphology of sanqiaspids remains poorly known. Here we report the first occurrence of Sanqiaspis in the Xujiachong Formation of Qujing, East Yunnan, and describe new material of Sanqiaspis from two other sites in South China. The new data corroborate the presence of the two median transverse canals in Sanqiaspis as a possible synapomorphy of the Sanqiaspidae. As a key member of the Xujiachong Assemblage, Sanqiaspis is known from the Xujiachong, Guanshanpo, Posongchong, and Si Ka formations. Stratigraphic correlation of eight Early Devonian sections in South China and North Vietnam indicates that the Sanqiaspis-bearing layers can be correlated with the transitional beds between the Lianhuashan and Nahkaoling formations in Liujing, Guangxi. Therefore, the middle-upper part of the Si Ka Formation in northern Vietnam and the upper part of the Lianhuashan Formation in Guangxi should be dated as Pragian, rather than Lochkovian. The fish assemblage from the Pragian of the South China Block documents the diversification of galeaspids, notably Huananaspidiformes, and exhibits much the same endemic pattern as that of early vascular plants and brachiopods. This endemism might be linked with the semi-closed epicontinental nature of the South China Sea during the Early Devonian, which formed a biodiversity hotspot as in the modern Red Sea.

Recent evidence highlights the role of adiponectin in the pathophysiology of autism spectrum disorder (ASD), yielding conflicting results. The aims of this study were (1) To assess the adiponectin levels of children with ASD and typical developing (TP); (2) To investigate the relationship between adiponectin levels and symptom severity of children with ASD. This is a single-center cross-sectional study from China. From December 2017 to November 2019, first-diagnosis and drug-naive children with ASD were included. Same TP children who were matched with clinical groups by gender and age were included as the control group. The enzyme-linked immunosorbent assay (ELISA) kit was used to determine serum concentrations of adiponectin. We recorded 176 children (88 were ASD and 88 were TP children) and 77.3% (n = 136) were boys and the mean age was 4.3 years (standard deviations [S.D.]: 1.2). The mean (S.D.) levels of adiponectin were 9.01(2.19) and 11.55(2.32) μg/ml for those with ASD and TP subjects. The difference between those two groups was significant (t = 7.169, p

We report a feasibility study of pure leptonic decay $D_s^+\to\mu^+\nu_\mu$ by using a fast simulation software package at STCF. With an expected luminosity of $1~\mathrm{ab}^{-1}$ collected at STCF at a center-of-mass energy of 4.009 GeV, the statistical sensitivity of the branching fraction is determined to be 0.3\%. Combining this result with the $c\rightarrow s$ quark mixing matrix element $|V_{cs}|$ determined from the current global Standard Model fit, the statistical sensitivity of $D_s^+$ decay constant, $f_{D_s^+}$, is estimated to be 0.2\%. Alternatively, combining the current results of $f_{D_s^+}$ calculated by lattice QCD, the statistical sensitivity of $|V_{cs}|$ is determined to be 0.2\%, which helps probe possible new physics beyond. The unprecedented precision to be achieved at STCF will provide a precise calibration of QCD and rigorous test of Standard Model., Comment: 8pages, 7 figures

A simple method based on a thiamonomethinecyanine dye (dye2) and duplex DNA system was constructed to detect Pb2+ by UV–Vis spectra. The absorption spectra of dye2 show dimers and monomers peak and the monomer–dimer equilibrium could be regulated with environmental change. Duplex DNA as a template was used to regulate distinct aggregates of cyanine dye in the presence of Pb2+. This system shows a specific absorption signal for Pb2+ detection.

Effects of various concentrations of Cu(2+) and Zn(2+) (0.0, 0.1, 0.25, 0.5, or 1.0 mg/L) on the growth, malondialdehyde (MDA), the intracellular calcium, and physiological characteristics of green algae, Cladophora, were investigated. Low Zn(2+) concentrations accelerated the growth of Cladophora, whereas Zn(2+) concentration increases to 0.25 mg/L inhibited its growth. Cu(2+) greatly influences Cladophora growth. The photosynthesis of Cladophora decreased under Zn(2+) and Cu(2+) stress. Cu(2+) and Zn(2+) treatment affected the content of total soluble sugar in Cladophora and has small increases in its protein content. Zn(2+) induced the intracellular calcium release, and copper induced the intracellular calcium increases in Cladophora. Exposure to Cu(2+) and Zn(2+) induces MDA in Cladophora. The stress concent of Cu(2+) was strictly correlated with the total soluble sugar content, Chla+Chlb, and MDA in Cladophora, and the stress concent of Zn(2+) was strictly correlated with the relative growth rate (RGR) and MDA of Cladophora.

To explore the traits contributing to invasion success of Eupatorium adenophorum, a noxious invasive perennial forb throughout the subtropics in Asia, Oceania, Africa, and USA, we compared the differences in ecophysiology and phenology between the invader and native E. japonicum under eight treatment combinations of two irradiances and four nitrogen additions in a two-year shadehouse experiment. The invader had significantly higher mass-based light-saturated photosynthetic rate (P max) than its native congener in all treatments, contributing to higher photosynthetic nitrogen-, phosphorus-, and energy-use efficiencies. The higher P max of the invader was associated with its higher nitrogen concentrations in the photosynthetic apparatus, which resulted from higher leaf nitrogen allocation to photosynthesis. The invader had higher specific leaf area and stomatal conductance at most of the treatments, also contributing to its higher P max. The invader was not constrained by the negative correlation between leaf lifespan and specific leaf area or P max. Leaf lifespan and total leaf area of the invader were greater than those of the native. From November to March the native congener was leafless, whereas the invader maintained a large area of leaves with relatively high P max. Biomass accumulated in these months accounted for more than 40 % of the total biomass of the invader. Our results indicate that both the ability to capture and utilize resources efficiently and the ability to use resources when they are unavailable to natives contribute to invasion success of E. adenophorum and emphasize the importance of exploring multiple, non-mutually exclusive mechanisms for invasions.

Alzheimer’s disease (AD) is a progressive neurodegenerative disease, which affects more and more people. But there is still no effective treatment for preventing or reversing the progression of the disease. Soluble amyloid-beta (Aβ) oligomers, also known as Aβ-derived diffusible ligands (ADDLs) play an important role in AD. Synaptic activity and cognition critically depend on the function of glutamate receptors. Targeting N-methyl-D-aspartic acid (NMDA) receptors trafficking and its regulation is a new strategy for AD early treatment. EphB2 is a key regulator of synaptic localization of NMDA receptors. Aβ oligomers could bind to the fibronectin repeats domain of EphB2 and trigger EphB2 degradation in the proteasome. Here we identified that overexpression of EphB2 with lentiviral vectors in dorsal hippocampus improved impaired memory deficits and anxiety or depression-like behaviors in APPswe/PS1-dE9 (APP/PS1) transgenic mice. Phosphorylation and surface expression of GluN2B-containing NMDA receptors were also improved. Overexpression of EphB2 also rescued the ADDLs-induced depletion of the expression of EphB2 and GluN2B-containing NMDA receptors trafficking in cultured hippocampal neurons. These results suggest that improving the decreased expression of EphB2 and subsequent GluN2B-containing NMDA receptors trafficking in hippocampus may be a promising strategy for AD treatment.