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In this paper, a new foam concrete-extruded polystyrene composite wall panel (FCPW) is proposed. In order to investigate the response of these wall panels to the loading conditions that may occur during an earthquake event, a total of three specimens were designed in this study to study the seismic performance of the wall panels with different sizes of cyclic loads applied to them. By analyzing the seismic parameters such as hysteresis curve, skeleton curve, ductility and stiffness degradation factor of the wall panels, it is concluded that the wall panels have good seismic performance. Both the test phenomenon and damage mechanism indicate that shear damage is the damage form of the specimen. Comparing the specimens, it can be seen that the height-to-width ratio and the strength of the specimen itself have obvious effects on the seismic performance. The larger the height-to-width ratio is, the larger the ductility is and the better the seismic performance is. The smaller the thickness of the concrete is, the smaller the ductility is and the worse the seismic performance is. This study helps to update the iteration of composite wall panels composed of extruded plastic board and concrete and provide a reference for future research. [ABSTRACT FROM AUTHOR]

The seasonal human coronaviruses (HCoVs) have zoonotic origins, repeated infections, and global transmission. The objectives of this study are to elaborate the epidemiological and evolutionary characteristics of HCoVs from patients with acute respiratory illness. We conducted a multicenter surveillance at 36 sentinel hospitals of Beijing Metropolis, China, during 2016–2019. Patients with influenza‐like illness (ILI) and severe acute respiratory infection (SARI) were included, and submitted respiratory samples for screening HCoVs by multiplex real‐time reverse transcription‐polymerase chain reaction assays. All the positive samples were used for metatranscriptomic sequencing to get whole genomes of HCoVs for genetical and evolutionary analyses. Totally, 321 of 15 677 patients with ILI or SARI were found to be positive for HCoVs, with an infection rate of 2.0% (95% confidence interval, 1.8%–2.3%). HCoV‐229E, HCoV‐NL63, HCoV‐OC43, and HCoV‐HKU1 infections accounted for 18.7%, 38.3%, 40.5%, and 2.5%, respectively. In comparison to ILI cases, SARI cases were significantly older, more likely caused by HCoV‐229E and HCoV‐OC43, and more often co‐infected with other respiratory pathogens. A total of 179 full genome sequences of HCoVs were obtained from 321 positive patients. The phylogenetical analyses revealed that HCoV‐229E, HCoV‐NL63 and HCoV‐OC43 continuously yielded novel lineages, respectively. The nonsynonymous to synonymous ratio of all key genes in each HCoV was less than one, indicating that all four HCoVs were under negative selection pressure. Multiple substitution modes were observed in spike glycoprotein among the four HCoVs. Our findings highlight the importance of enhancing surveillance on HCoVs, and imply that more variants might occur in the future. [ABSTRACT FROM AUTHOR]

Objective To prepare PLGA microspheres containing follicle stimulating hormone (FSH) or stem cell factor (SCF) and investigate the effects of sustaining release in vitro and in vivo. Methods Microspheres were prepared by a double-emulsification solvent evaporation method, releasing experiments were performed in vitro by culture method and in vivo by injection of microspheres in the rat hind leg muscle. Results The FSH-PLGA microspheres could release for 28 days and the burst release rate was 17.2% in vitro, release for 17 days in vivo; The SCF-PLGA microspheres could release 28 days and the burst release rate was 8.8% in vitro, release for 17 days in vivo. Conclusion The FSH or SCF microspheres could release for long lime in vitro and in vivo, suggesting the method to prepare FSH or SCF microspheres is feasible. [ABSTRACT FROM AUTHOR]

Quasi-cyclic low-density parity-check code (QC-LDPC) has advantage of reducing public key size in constructing cryptography, due to its parity-check matrix can build by block cycling. However, it cannot resist the low-weight code searching attack. This paper proposed a new public-key cryptography based on quasi-cyclic medium-density parity-check code (QC-MDPC), and a special bit flipping decode algorithm. Compared with the classical Goppa code-based PKC,this scheme achieves 93 times reduction of public key size in the same security level, lower complexity in both of encryption and decryption and high security, since it resists the dual code attack and information set decoding attack. [ABSTRACT FROM AUTHOR]

The replacement policy for a deteriorating system subject to cumulative shocks is studied. Assume that each shock arriving in the system's operating time can cause a random damage to the system, the damages are additive, and the system fails once the accumulated amount of damages exceeds a prefixed threshold. When a failure occurs, we can repair or replace the system. For such a deteriorating system, we assume that the thresholds are geometrically decreasing in the number of repairs taken, and the consecutive repair times form an increasing geometric process. By adopting the replacement policy N of that the system is maintained after the previous (N - 1)th failures and is replaced at the time of the Nth failure, we derive the explicit expression for the long-run average cost rate (ACR), and determine the optimal policy N* for minimizing the long-run ACR. A numerical example is also given. [ABSTRACT FROM AUTHOR]

The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology. The [16 + 2] construction achieved by condensation between a 16-connected carbazolyl dicyanobenzene-based building block (CzTPN) and linear diamino linkers (BD or Bpy) affords two 3D COFs (named CzBD COF and CzBpy COF). Furthermore, attributed to the well-organized donor-acceptor (D-A) heterojunction, the Ni chelated CzBpy COF (Ni@CzBpy COF) exhibits excellent performance for photoredox/Ni dual catalytic C(sp 3 )-C(sp 2 ) cross-coupling of alkyltrifluoroborates with aryl halides, achieving a maximum 98% conversion and 94% yield for various substrates. This work developed the first case of high-connectivity COFs bearing 16-connected units, which is the highest connectivity reported until now, and achieved efficient photocatalysis applications, thus greatly enriching the possibilities of COFs.

The ovarian germline stem cells(OGSCs) cultured in the optimized culture system were used as the research object to observe the effect of Tripterygium glycosides(TG) on OGSCs and explore the mechanism of reproductive toxicity by the Notch signaling pathway. Cell counting kit-8(CCK-8) was used to observe the viability level of OGSCs in mice cultured in vitro by TG of 3.75, 7.5, and 15 μg·mL~(-1). Immunofluorescence technology and reverse transcription-polymerase chain reaction(RT-PCR) were used to detect the protein and gene expression level of OGSCs marker mouse vasa homologue(MVH) and octamer-binding transcription factor 4(Oct4) by TG of 3.75 μg·mL~(-1). RT-PCR detected the gene expression of neurogenic locus Notch homolog protein 1(Notch1), Hes family BHLH transcription factor 1(Hes1), and jagged canonical Notch ligand 1(Jagged1). The RNA was extracted for transcriptome analysis to analyze the mechanism of action of TG intervention on OGSCs. 3.75 μg·mL~(-1) of TG was combined with 40 ng·mL~(-1) Notch signaling pathway γ-secretagocin agonist jagged canonical notch ligand(Jagged) for administration. CCK-8 was used to detect the viability level of OGSCs. Double immunofluorescence technology was used to detect the protein co-expression of MVH with Hes1, Notch1, and Jagged1. The results showed that compared with the blank group, the TG administration group significantly inhibited the activity of OGSCs(P<0.01 or P<0.001). It could reduce the protein and gene expression of OGSC markers, namely MVH and Oct4(P<0.05, P<0.01, or P<0.001). It could significantly inhibit the gene expression of Notch1, Hes1, and Jagged1(P<0.001). Transcriptomic analysis showed that TG affected the growth and proliferation of OGSCs by intervening Jagged1, a ligand associated with the Notch signaling pathway. The experimental results showed that the combination of Notch signaling pathway γ-secretagorein agonist Jagged could significantly alleviate the decrease in OGSC viability induced by TG(P<0.001) and significantly increased the OGSC viability compared with the TG group(P<0.001). It also could significantly increase the co-expression of MVH/Jagged1, MVH/Hes1, and MVH/Notch1 proteins(P<0.01 or P<0.001). It suggested that TG play the role of γ-secretagorease inhibitors by downregulating the OGSC markers including MVH and Oct4 and Notch signaling pathway molecules such as Notch1, Hes1, and Jagged1, participate in the OGSC pathway, and mediate reproductive toxicity caused by the Notch signaling pathway.

The aim of the study is to investigate the effect of salvianolic acid B (SalB) on blood-brain barrier (BBB) in rats after cerebral ischemia-reperfusion, and to illustrate its possible mechanisms. Cerebral ischemia-reperfusion was induced by middle cerebral artery occlusion in rats. The break-down of BBB was indicated by extravasations of immunoglobulin (IgG) monitored with immunohistochemistry. The expression of MMP-9 and NOS2 in the brain was determined by immunohistochemistry, and the expression of p-p38 and p-ERK1/2 was detected by Western blotting. It was shown that on day 2 after ischemia-reperfusion the IgG accumulated around the vascular boundary zone, suggesting the break-down of BBB, and the expression of MMP-9 and NOS2 up-regulated at the same time. The result of Western blotting suggested that the expression of p-p38 and p-ERK1/2 increased. On day 7 after ischemia-reperfusion the. expression of MMP-9 and NOS2 was about the same level as day 2, the expression of p-p38 was higher than that on day 2 and the expression of p-ERK1/2 was slightly lower than that on day 2. SalB (1 and 10 mg x kg(-1)) significantly alleviated the extravasations of immunoglobulin induced by cerebral ischemia-reperfusion (P < 0.05). On day 2 and day 7 SalB attenuated the expression of MMP-9 and NOS2 (P < 0.05). SalB (10 mg x kg(-1)) reduced the expression of p-p38 and p-ERK1/2 apparently on day 2 and 7 after ischemia-reperfusion (P < 0.05). SalB (1 mg x kg(-1)) inhibited the expression of p-p38 on day 7 after ischemia-reperfusion (P < 0.05). The results indicate that SalB protects blood-brain barrier in rats after cerebral ischemia-reperfusion by inhibiting the MAPK pathway.