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In order to enhance the physical barrier performance of polyaniline(PANI)/polyurethane(PU) coating against corrosive medium, the introduction of two-dimensional material in the coating is one of the effective methods. PU coating matrix was synthesized from 2, 4-diisocyanate (TDI) and 3, 3′-dichloro-4, 4′-diamino diphenylmethane(MOCA), and MXene@PANI was synthesized by intercalation reaction of PANI with Ti3C2Tx.Then protective coating of MXene@PANI/PU was obtained by adding MXene@PANI into PU. The results show that when the mass ratio of MXene/PANI is 1∶1, no obvious corrosion occurs on the surface of the MXene@PANI/PU coating after 60 days of salt spraying. The corrosion current is 3.709×10-9 A·cm-2, and the impedance modulus is 1.93×108 Ω·cm2. The reason is that MXene improves the electrochemical activity of PANI and thus enhances the electrochemical anticorrosion performance of PANI. On the other hand, MXene nanoplates as a two-dimensional barrier can prevent the corrosive medium from entering into the coating, which improves the long-term protective performance of the coating.

Objective To investigate the expression of heparanase-2 (HPSE2) in gastric cancer tissues, and explore its effect on the survival and prognosis of the cancer and invasion and migration of the cancer cells. Methods Immunohistochemical staining of HPSE2 was performed on gastric cancer tissue chip to examine the expression level of HPSE2 in gastric cancer and paracancerous tissues. The correlation of HPSE2 expression level with clinical features, survival, prognosis and prognostic factors were analyzed. The lentival vectors of HPSE2 overexpression were constructed, and then transfected in gastric cancer cell lines SGC7901 and MKN28. The effect of HPSE2 overexpression on invasion and migration of gastric cancer cells were detected using Transwell analysis. Results The mean pathological score of HPSE2 was 4.56 in gastric cancer tissue, and 7.18 in paracancer tissues, showing that the expression was significantly lower in gastric cancer than paracancer tissues (P < 0.05). The expression level of HPSE2 was closely correlated with the tumor size, lymph node metastasis, and clinical staging. The patients with higher HPSE2 expression had obviously shorter median survival time and cumulative survival rate than those with lower expression (P < 0.05). Cox proportional risk model showed that clinical stage, tumor size and HPSE2 protein expression were risk factors for prognosis of gastric cancer patients (P < 0.05). Overexpression of HPSE2 could remarkably inhibit the invasion and migration of gastric cancer cells. Conclusion HPSE2 is lowly expressed in gastric cancer tissues, and is associated with the tumor size, lymph node metastasis, survival and prognosis of gastric cancer. Overexpression of HPSE2 could inhibit the invasion and migration of gastric cancer cells.

This paper presents the stable isotopic compositions from the cave dripwater and actively forming soda straw stalactites collected from Wanxiang Cave, Wudu, Gansu, located on the Qinghai-Tibetan Plateau and Loess Plateau transition zone, China. The δ18Odw and δDdw of dripwater samples in the cave plot directly on the local MWL, constructed by using GNIP data from 3 sites surrounding the cave regions (Lanzhou, Xi’an, and Chengdu), the nearest site to the cave, suggesting that there is a close relationship between the δ18Odw of the cave water and the δ18O of the precipitations. Using the measured δ18Odw and δ18Omc values from the mid-farthest parts from the cave entrance and the carbonate paleotemperature equation, the calculated tem peratures range from 8.9 to 12.4°C, with the mean value of 10.7°C and the temperature calculated at 8 locations in the farthest part of the cave is in the range of 10.1–12.4°C with the mean value of 11.5°C, being consistent with the survey value(10.99°C)in the cave, slightly lower than the mean annual temperature (14.4°C) in Wudu. This suggests that modern speleothems are forming under isotopic equilibrium and their isotopic composition accurately reflects the mean annual temperature at the surface, indicating that the isotopic composition of the modern speleothems records local temperature change with credibility.

For order-of-addition experiments, the response is affected by the addition order of the experimental materials. Consequently, the main interest focuses on creating a predictive model and an optimal design for optimizing the response. Van Nostrand proposed the pairwise-order (PWO) model for detecting PWO effects. Under the PWO model, the full PWO design is optimal under various criteria but is often unaffordable because of the large run size. In this paper, we consider the D-, A- and M. S. -optimal fractional PWO designs. We first present some results on information matrices. Then, a flexible and efficient algorithm is given for generating these optimal PWO designs. Numerical simulation shows that the generated design has an appealing efficiency in comparison with the full PWO design, though with only a small fraction of runs. Several comparisons with existing designs illustrate that the generated designs achieve better efficiencies, and the best PWO designs and some selected 100% efficient PWO designs generated by the new algorithm are reported. [ABSTRACT FROM AUTHOR]

Background: Well-balanced interactions between gut microbiota and the immune system are essential to prevent chronic intestinal inflammation, as observed in inflammatory bowel diseases (IBD). Toll-like receptor 4 (TLR4) functions as a sensor mediating the crosstalk between the intestinal commensal microbiome and host immunity, but the influence of TLR4 on the shaping of intestinal microbiota and immune responses during colon inflammation remains poorly characterized. We investigated whether the different susceptibilities to colitis between wild-type (WT) and TLR4−/− mice were gut microbiota-dependent and aimed to identify the potential immunity modulation mechanism. Methods: We performed antibiotic depletion of the microbiota, cohousing experiments, and faecal microbiota transplantation (FMT) in WT and TLR4−/− mice to assess the influence of TLR4 on intestinal microbial ecology. 16S rRNA sequencing was performed to dissect microbial discrepancies, and dysbiosis-associated immune perturbation was investigated by flow cytometry. Akkermansia muciniphila (A. muciniphila)-mediated immune modulation was confirmed through the T-cell transfer colitis model and bone marrow chimaera construction. Results: TLR4−/− mice experienced enhanced susceptibility to DSS-induced colitis. 16S rRNA sequencing showed notable discrepancy in the gut microbiota between WT and TLR4−/− mice. In particular, A. muciniphila contributed most to distinguishing the two groups. The T-cell transfer colitis model and bone marrow transplantation (BMT) consistently demonstrated that A. muciniphila ameliorated colitis by upregulating RORγt+ Treg cell-mediated immune responses. Mucosal biopsies from human manifested parallel outcomes with colon tissue from WT mice, as evidenced by the positive correlation between TLR4 expression and intestinal A. muciniphila colonization during homeostasis. Conclusions: Our results demonstrate a novel protective role of TLR4 against intestinal inflammation, wherein it can modulate A. muciniphila-associated immune responses. These findings provide a new perspective on host-commensal symbiosis, which may be beneficial for developing potential therapeutic strategies. CehHU1DpMuC43wfy6GXbFM Video abstract. [ABSTRACT FROM AUTHOR]