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The age of the Silurian “Lower Red Beds” (LRBs), which occur widely in South China, has long been controversial because of the scarcity of index fossils. Here, we report a fauna with abundant trilobites from the LRBs in Wuhan, Middle Yangtze region, consisting of Aulacopleura (Paraaulacopleura) pijiazhaiensis, ‘Encrinuroides’ yichangensis, Gaotania hubeiensis, Hyrokybe gaotanensis, Japonoscutellum yichangense, Latiproetus latilimbatus, and Ptilillaenus lojopingensis. These trilobites are common in the Leijiatun, upper Xiangshuyuan, Shihniulan, and Lojoping formations in the Upper Yangtze region, and belong to the middle to upper Aeronian Ptilillaenus or ‘Encrinuroides’–Ptilillaenus–Latiproetus assemblages. The discovery of this trilobite assemblage suggests that the LRBs are probably partly of middle–late Aeronian age in the Middle Yangtze region. Thus, the lower boundary of the LRBs is likely diachronous in the Yangtze region, ranging from the middle–late Aeronian to the early Telychian. The discovery of the Ptilillaenus assemblage in the Wuhan LRBs expands the paleogeographic distribution of this assemblage and provides evidence of deeper depositional environment of the LRBs in the study area versus shallow waters in other areas of the Yangtze region.

CaBi4Ti4O15 (CBT)-based Aurivillius high-temperature piezoceramics with different Sb–Mn co-doping amounts were synthesized via the conventional sintering technique. The influences of doping amount on the product were studied via their crystal structure, microstructure, and piezoelectric performance. It is found that an appropriate Sb–Mn co-doping amount can effectively optimize the crystal structure and decrease the oxygen vacancy concentration in CBT ceramics, leading to enhanced electrical properties. Optimized electrical performance with a high Curie temperature (TC) of 792 °C and a remarkable piezoelectric coefficient (d33) of 25 pC/N were achieved at a doping amount (x) of 0.05. Furthermore, this ceramic is found to exhibit an excellent thermal stability, with d33 retaining 88% of its original value after annealing at 600 °C for 2 h. Moreover, this ceramic shows a high electrical resistivity (ρ) of 1.35×108 Ω·cm with a small dielectric loss (tan δ) of 1.7% at 400 °C. Because of such outstanding piezoelectric performance, it is believed that these Sb–Mn co-doped CBT ceramics could be potential candidates for high-temperature piezoelectric applications.

Polysaccharides were extracted by hot water and alkali in sequence from Dolichos lablab L. hull, and further purified by ion-exchange and gel columns. Hot water extracted D. lablab hull polysaccharide (DLHP) was rich in glucuronoxylan and pectin, and alkali extracted polysaccharide (DLHAP) mostly embraced glucuronoxylan. The structures of purified glucuronoxylans from DLHP and DLHAP were mainly analyzed by HPAEC-PAD, methylation combined with GC–MS, NMR and SEC-MALLS. DLHP-1 was identified as acetylated glucuronoxylan containing →4)-β-Xylp-(1→ backbone with substitution at O-2 site by α-GlcpA/4-O-methyl-α-GlcpA. The molar ratio of β-Xylp to α-GlcpA was 6.9:1, and acetylation was mainly at O-3 site of β-Xylp with acetylation degree of 21.5%. DLHP-1 and DLHP-2 had similar physicochemical properties, except for molecular weight (Mw). DLHAP-1 was the non-methylated glucuronoxylan almost without acetylation, and it had the molar ratio of β-Xylp to α-GlcpA of 5.6:1. Besides, DLHP-1 (Mw of 20.0 × 103 g mol−1) adopted semi-flexible chain, while DLHAP-1 (Mw of 15.4 × 103 g mol−1) showed flexible chain. These results provided a structural basis for study on polysaccharides from D. lablab hull, which was benefit for understanding biological activities and developing functional food or pharmaceuticals of D. lablab.

Rationale Hematoma expansion (HE) aggravates brain injury after intracerebral hemorrhage (ICH) and hypertension is a key contributor to HE. Plasma kallikrein (PK) is involved in hemorrhagic transformation in ischemic stroke mice. This study was conducted to explore the role of PK in HE in hypertensive ICH. Methods Hypertension was achieved by continuous infusion of angiotensin II (Ang II) with an osmotic pump in C57BL/6 mice. ICH was achieved by stereotactic intrastriatal injection of blood. PK-specific antibody and platelet glycoprotein VI (GPVI) agonists were administered to intervene in hematoma expansion. The hematoma volume was indicated by the erythrocyte components hemoglobin and carbonic anhydrase-1 in the ipsilateral brain hemisphere. Results Ang II-induced hypertensive mice showed enhanced hematoma expansion and worsened neurologic deficits after ICH modeling. Moreover, intrastriatal injection of blood from Ang II-treated mice into normal mice increased the area of secondary hemorrhage more than blood from untreated mice. Mechanistically, elevated PK was found in Ang II-infused mice whereas, inhibition of PK and administration of the GPVI agonist convulxin decreased hematoma expansion and improved neurologic deficits after ICH. Conclusions These findings suggest that PK inhibition and GPVI agonist treatment might serve as potential methods to intervene in HE after ICH.

Archaeologists are increasingly interested in networks constructed from site assemblage data, in which weighted network ties reflect sites’ assemblage similarity. Equivalent networks would arise in other scientific fields where actors’ similarity is assessed by comparing distributions of observed counts, so the assemblages studied here can represent other kinds of distributions in other domains. One concern with such work is that sampling variability in the assemblage network and, in turn, sampling variability in measures calculated from the network must be recognized in any comprehensive analysis. In this study, we investigated the use of the bootstrap as a means of estimating sampling variability in measures of assemblage networks. We evaluated the performance of the bootstrap in simulated assemblage networks, using a probability structure based on the actual distribution of sherds of ceramic wares in a region with 25 archaeological sites. Results indicated that the bootstrap was successful in estimating the true sampling variability of eigenvector centrality for the 25 sites. This held both for centrality scores and for centrality ranks, as well as the ratio of first to second eigenvalues of the network (similarity) matrix. Findings encourage the use of the bootstrap as a tool in analyses of network data derived from counts.

Background Suicide rates in China have declined substantially in the last two decades, however, the correlates of the decreases are still unclear. Methods Using hospital-based suicidal acts registry system in Meixian county, we reviewed all episodes of suicidal behaviors presented at hospitals from 2009 to 2014. The data was combined with the suicides reported in the same period by the county's Center for Disease Prevention and Control. Stratified by gender and method, age-standardized incidences of suicide death, suicide attempts, suicidal acts, as well as the case-fatalities of suicidal acts, were calculated. Joinpoint regression analysis was applied to test the time trends changes of the annual incidences and case-fatalities. Correlation coefficients between suicide rates and case-fatality were estimated. Results Age-standardized suicide rates among females declined by 20.4% per year, meanwhile, overall suicide rates were characterized by downward trend without statistical significance. The annual proportions of suicide deaths by pesticide self-poisoning ranged from 57.1% to 82.6%. There were positive or marginally positive correlations between suicide rates and case-fatalities of suicidal acts in gender- and method-specific groups (r values range from 0.77 to 0.89). Limitations Underreporting in the hospital-based registry system and misclassification in the death reporting system. Changes in other related factors are not yet accessible. Conclusion Suicide rates in females declined prominently in Meixian from 2009 to 2014, even though overall suicide rates remained steady. Pesticide ingestion were most common suicide method. Restriction of pesticide and reduction in the case-fatality are critical targets of suicide prevention in rural China.