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The hot deformation characteristics of Nickel‐based corrosion resistant alloy was studied in the temperature range of 1050°C to 1200°C and the strain rate range of 0.001 to 0.1 second−1 by employing hot compression tests. The results show that the peak stress increases with decreasing temperature and increasing strain rate, and the apparent activation energy is about 409 kJ/mol. Based on the Avrami equation through using the critical strain (εc) and the strain for 50% DRX (ε0.5), a kinetic model for dynamic recrystallization (DRX) was established, where the model parameters could be obtained using the modified Zener‐Hollomon parameter (Z*). Applying the model, the predicted value of the steady‐state strain (εss) and the strain for maximum softening rate (εm) agree well with the experimental results. Accordingly, the relationship between εm and ε0.5 is established, which is mainly dependent on the Avrami exponent (n). When n < 3.25, εm becomes less than ε0.5 and the difference in between decreases with increasing the strain rate or decreasing the deformation temperature. Finally, through observing DRX microstructure under different deformation conditions, a power law relation between DRX grain size (Ddrx) and Z*, with an exponent of −0.36, was found. [ABSTRACT FROM AUTHOR]

Aim: Surgeons have concerns whether high ligation (HL) of the inferior mesenteric artery (IMA) increases the incidence of anastomotic leakage (AL). This meta‐analysis aimed to evaluate the influence of HL of the IMA on AL compared with low ligation (LL). Methods: PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials and ClinicalTrials.gov databases were searched. Randomized controlled trial studies that compared HL with LL of the IMA in anterior resection for rectal cancer and reported AL outcomes were eligible for inclusion. The odds ratios and mean differences were analysed by a random‐effects model. Trial sequential analysis was performed to minimize the risk of random errors. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to evaluate the quality of evidence for outcomes. Results: Of the 531 records screened, five randomized controlled trials with 779 patients were selected for analysis. The pooled incidence of AL was 12.1% (95% Cl 7.77–18.26) in the HL group and 9.7% (95% Cl 5.79–15.82) in the LL group (OR 1.20, 95% CI 0.77–1.87, P = 0.42). In trial sequential analysis, the cumulative Z‐score curve exceeded the futility boundary, although the required information size of 1060 had not been reached. The quality of evidence was judged to be high according to the GRADE approach. Conclusions: This meta‐analysis shows that HL of the IMA does not increase the incidence of AL in anterior resection for rectal cancer. [ABSTRACT FROM AUTHOR]

Excavators are widely used at various construction sites, and they can significantly reduce difficulties during construction and improve construction efficiency. However, conventional excavators still exhibit many shortcomings. In certain construction environments that require precision, the construction accuracy cannot be guaranteed because excavators usually operate in harsh environments. Hence, they can cause potential life hazards to the drivers in certain situations. To address these issues, an excavator automatic control system is developed via retrofitting, modelling, and designing a control program for an excavator. This system can realise three working modes: manual operation, remote control operation, and automatic operation. A test prototype based on the aforementioned concept is developed and relevant experiments are performed. The results under automatic operation mode show that the automatic control system can move the excavator smoothly along the expected trajectory. The fluctuation in the operation velocity is low, and the positioning error to the target position is within 7 cm. Thus, the system can realise the desired control accuracy and satisfy other task design requirements. [ABSTRACT FROM AUTHOR]

Local tumour sites lead to pathological angiogenesis and lymphangiogenesis due to malignant conditions such as hypoxia. Although VEGF and VEGFR are considered to be the main anti-tumour treatment targets, the problems of limited efficacy and observable side effects of some drugs relevant to this target still remain to be solved. Therefore, it is necessary to identify new therapeutic targets for angiogenesis or lymphangiogenesis. The neuropilin family is a class of single transmembrane glycoprotein receptors, including neuropilin1 (NRP1) and neuropilin2 (NRP2), which could act as co-receptors of VEGFA-165 and VEGFC and play a key role in promoting tumour proliferation, invasion and metastasis. In this review, we introduced the schematic diagram to visually reveal the function of NRP1 and NRP2 in enhancing the binding affinity of VEGFR2 to VEGFA-165 and VEGFR3 to VEGFC, respectively. We also discussed the signalling pathways that depend on the co-receptors NRP1 and NRP2 and some existing targeted therapeutic strategies, such as monoclonal antibodies, targeted peptides, microRNAs and small molecule inhibitors. It will contribute a vital foundation for the future research and development of new drugs targeting NRPs. NRP1 acts as a co-receptor with VEGFR2 and the pro-angiogenic factor VEGFA-165 to up-regulate tumour angiogenesis by promoting endothelial cells proliferation, survival, migration, invasion and by preventing of apoptosis. NRP2 acts as a co-receptor with VEGFR3 and the pro-lymphogenic factor VEGFC to facilitate tumour metastasis by promoting lymphangiogenesis. Although NRP1 and NRP2 do not have enzymatic signalling activity, the affinity of VEGFR2 for VEGFA-165 and VEGFR3 for VEGFC can increase in a co-receptor manner, as detailed in the schematic. The exclusive roles of NRP1 and NRP2 in signalling pathways are specifically described to emphasise the molecular regulatory mechanisms involved in co-receptors. Various studies have shown that the co-receptors NRP1 and NRP2 can be directly or indirectly targeted by different methods to prevent tumour angiogenesis and lymphangiogenesis. Therapeutic strategies targeting NRPs look promising soon as evidenced by preclinical and clinical studies. [ABSTRACT FROM AUTHOR]

The differential constituents in leaves, stems and roots of Polygonum multiflorum Thunb. were analyzed by ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC/ESI-Q-TOF-MS) and by multivariate statistical analysis. The established extraction and analysis method showed relative standard deviations (RSDs) for intra-day precision of less than 3.40%, for repeatability of less than 4.06% and for stability of less than 5.10%. Principal component analysis and orthogonal projections to latent structures discriminant analysis of the UPLC/ESI-Q-TOF-MS data showed good ability to classify the leaves, stems and roots of P. multiflorum Thunb. The differential constituents, such as stilbenes, polygoacetophenoside, flavonoids and anthraquinones, accounting for variations between the leaves, stems and roots, were filtered through the variable importance in projection values and were further identified by elemental composition analysis, mass fragmentation data and retention times of available standards. Differences between the chemical compositions in the leaves, stems and roots of P. multiflorum Thunb. were closely related to their various therapeutic effects. This UPLC/ESI-Q-TOF-MS-based analytical strategy could be further utilized to evaluate the overall quality of traditional Chinese medicines and their differences of chemical constituents in different parts of the plant and/or in the plants of different geographical locations. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLRs) play an important role in regulating immune responses during pathogen infection. However, roles of TLRs on T cells reside in the mesenteric lymph node (MLN) were not be fully elucidated in the course of S. japonicum infection. In this study, T lymphocytes from the mesenteric lymph node (MLN) of S. japonicum-infected mice were isolated and the expression and roles of TLR2, TLR3, TLR4, and TLR7 on both CD4+ and CD8+ T cells were compared. We found that the expression of TLR7 was increased in the MLN cells of S. japonicum-infected mice, particularly in CD4+ and CD8+ T cells (P < 0.05). R848, a TLR7 agonist, could enhance the production of IFN-γ from MLN T cells of infected mice (P < 0.05), especially in CD8+ T cells (P < 0.01). In TLR7 gene knockedout (KO) mice, the S. japonicum infection caused a significant decrease (P < 0.05) of the expression of CD25 and CD69, as well as the production of IFN-γ and IL-4 inducted by PMA plus ionomycin on both CD4+ and CD8+ T cells. Furthermore, the decreased level of IFN-γ and IL-4 in the supernatants of SEA- or SWA-stimulated mesenteric lymphocytes was detected (P < 0.05). Our results indicated that S. japonicum infection could induce the TLR7 expression on T cells in the MLN of C57BL/6 mice, and TLR7 mediates T cell response in the early phase of infection. [ABSTRACT FROM AUTHOR]