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Poly(arylene ether nitrile)s (PAENs) play an important role in special engineering materials owing to their excellent mechanical strength and superior thermal stability. In this study, PAEN and carboxyl-functionalized poly(arylene ether nitrile) (CPAEN) were successfully synthesized and their thermal parameters were determined through thermogravimetric analysis and differential scanning calorimetry to investigate the thermal decomposition kinetics and thermal stability. The results indicate that both PAEN and CPAEN exhibited high glass transition temperature and initial decomposition temperature. Meanwhile, the effects of the side groups on the thermal stability and the decomposition kinetic parameters of PAEN and CPAEN under nitrogen were discussed systematically. The kinetic parameters of PAEN and CPAEN were determined using the Kissinger and Ozawa methods, respectively. It reveals that the activation energy ( E) values of PAEN obtained using the Kissinger and Ozawa methods were 192.45 and 206.63 kJ/mol, and the corresponding E values of CPAEN were 161.20 and 162.72 kJ/mol, respectively. The thermal decomposition mechanism of PAEN and CPAEN obtained from Coats–Redfern methods goes for F3and D1models, respectively.

This study aimed to compare the efficacy of allogeneic stem cell transplantation (allo-SCT) versus autologous SCT (auto-SCT) in patients with relapsed or refractory B-cell non-Hodgkin lymphoma (B-NHL). Medline, CENTRAL, and EMBASE databases through December 31, 2019 were searched. The primary endpoints were overall survival (OS) and progression-free survival (PFS) rates. The secondary outcomes include transplant-related mortality (TRM), event-free survival, relapse/or progression, and nonrelapse mortality (NRM). The 18 retrospective studies enrolled 8,058 B-NHL patients (allo-SCT = 1,204; auto-SCT = 6,854). The OS was significantly higher in patients receiving auto-SCT than allo-SCT (pooled odds ratio [OR]: 1.69, 95% confidence interval [CI]: 1.29 to 2.22, P < 0.001), but no significant difference was found in PFS (pooled OR: 0.98, 95% CI: 0.69 to 1.38, P = 0.891). Auto-SCT patients also had lower TRM and NRM (TRM: OR = 0.23, P < 0.001; NRM: OR = 0.16, P < 0.001), but higher relapse or progression rate (OR = 2.37, P < 0.001) than allo-SCT patients. Subgroup analysis performed for different grades and subtypes of B-NHL showed higher OS in auto-SCT patients with high-grade B-NHL and diffused large B-cell lymphoma (DLBCL). There was, nevertheless, higher PFS in allo-SCT patients with low-grade B-NHL and follicular lymphoma (FL), and lower PFS in allo-SCT patients with DLBCL than their auto-SCT counterparts. In conclusion, the meta-analysis demonstrated that relapsed or refractory B-NHL patients who received auto-SCT have improved OS than those treated with allo-SCT, especially among those with DLBCL, but lower PFS among those with FL. However, the study is limited by a lack of randomized trials, patients’ heterogeneity, and possible selection bias.

Background: Multiple myeloma (MM) is the second most common hematological neoplasm. Wide administration of bortezomib significantly improves the survival of MM patients compared with conventional chemotherapy. Bromodomain-containing protein 4 (BRD4) inhibitors also have been demonstrated to retard cell proliferation and induce cellular apoptosis in various cancers. However, it is unclear whether the BRD4 inhibitor nitroxoline plus bortezomib has a synergistic anti-tumor effect on MM. Methods: Cell viability was determined via 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle and cell apoptosis were assessed via flow cytometry. Protein expression levels were determined via western blotting. The expression of apoptosis-related proteins in xenograft tissue were detected by means of immunohistochemistry. Results: Treatment with nitroxoline or bortezomib suppressed cell proliferation, and caused G0/G1 phase arrest and apoptosis in H929 and RPMI8226 cells. Furthermore, nitroxoline intensified the retardation of cell proliferation, as well as further enhanced the G0/G1 phase arrest and apoptosis induced by bortezomib in H929 and RPMI8226 cells. The western blot analysis revealed that nitroxoline or bortezomib treatment markedly diminished the levels of Bcl-2 and cyclin D1, and increased the levels of p21, Bax, cleaved PARP and cleaved caspase-3. Combination of these two agents was observed to result in further marked changes on these levels compared with nitroxoline or bortezomib treatment alone. What is more, in the xenograft tumor model, combinative treatment markedly inhibited tumor growth compared with the single drug treatment. Conclusion: Combination of bortezomib with nitroxoline has a synergistic anti-tumor activity in MM cells and may be a novel treatment method for MM.

The flammable and the mechanical effects of silica (SiO2) on the halogen-free, flame-retarded ethylene–octene copolymer (POE)/polypropylene (PP) composites were investigated. Through the thermal stability analysis and the combustion test, it was found that the SiO2 had a synergistic effect on the intumescent flame retardant (IFR), especially when the SiO2 content was 3 wt%. According to the results of mechanical properties, the tensile strength of composites increased with the rising SiO2 content and most of the impact strength is retained. The fracture morphology showed the state of SiO2/IFR particles in the POE/PP blends, which reflected that with the increasing SiO2 content and the decreasing IFR content, the aggregates became less compact and the size of aggregates became smaller.

One of the most critical challenges for turbine-based combined cycle propulsion systems utilized in hypersonic civil aircrafts (Mach 0 to Mach 5) lies in guaranteeing the propulsion system to operate efficiently and stably along a very wide operating range. This has resulted in a need to investigate the matching restraints between the inlet and turbine-based combined cycle engine and nozzle from the integration point of view at the early stage of design. To get a good understanding of this integration concept design process, in this article, several basic design principles were first put forward. Next, a fast, versatile and trusted modular analysis tool for this concept design was developed and implemented. Third, several issues on this concept were analyzed including the design issues, the mechanisms of the variable geometries as well as the control schedules. Finally, a solution for the turbine-based combined cycle propulsion system was carried out and discussed. The results show that at least 11 total variables were required to be adopted in the variable cycle propulsion system to meet the basic mission requirements for Mach 5 civil airplane. How to guarantee these variable geometries function efficiently and reliably along the wide flight regime is one of the most critical technology challenges to make this concept feasible. The uniqueness of the developed analysis tool lies in that it affords a platform capable of investigating the design constraints and the matching relationships between the various propulsion components along a wide operating range, which is beneficial to predict the potential critical technological barriers at the early design stage.