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Compared with large HAWT, the power coefficient and economical performance of the micro HAWT are inferior. However, due to flexible deployment, rapid installation, easy-to-use and low cost, it is still necessary to carry out research on micro HAWT to improve their performance. As a structure proven to be able to increase the power coefficient of HAWT effectively, the aerodynamic characteristics of the micro counter-rotating HAWT (CRWT) is studied in detail by experiments and LBM-LES simulation in this paper. Firstly, the results show the micro CRWT can enhance the power coefficient by two schemes. One is that the equal diameter counter rotating rotors with certain pitch angle can achieve a maximum power coefficient in a wider range of speed. The other is to use the vice rotor to enhance the power output of the main rotor, whether the vice rotor is in front rotor or rear, the rotation of the vice rotor can significantly improve power coefficient of the main rotor, so as to enhance the power coefficient of the total system. Then the aerodynamic mechanism of the Vice-Main and Main-Vice rotor schemes is further discussed with LBM-LES result in detail.

During the concrete pouring process of a dam construction, timely and accurate temperature monitoring is of great significance to reveal the thermal distribution characteristics and evolution process, and control concrete cracking. In this study, a positioning method of temperature sensors (PMTS) in a concrete dam is developed to determine the arrangement of temperature sensors quantitatively. The proposed positioning method is related to the restructured thermal field based on the natural neighbor interpolation algorithm, and the cross-validation. Based on the method, thermometers, distributed optical fibers and infrared thermal imagers are optimally installed in a super-high arch dam for real-time measurement of concrete temperature. The results show that the PMTS is reasonable and reliable for obtaining the dam global thermal field. The on-site temperature monitoring data indicate that the time and space temperature distribution law of the restructured thermal field is consistent with the actual situation of the super-high arch dam. In addition, the cons and pros, and improvement of the PMTS are further discussed. The proposed PMTS is a valuable method to monitor the global thermal field of concrete dams.

The effectiveness of enucleation in treatment for low-grade (G1, G2) small (≤2 cm) non-functional pancreatic neuroendocrine tumors (sNF-pNETs) remains controversial. This study investigated short- and long-term outcome of enucleation comparing with regular pancreatectomy in patients with sNF-pNETs.The clinical data of patients with sNF-pNETs who underwent surgery in our hospital from January 2000 to December 2017 were retrospectively collected. Short- and long-term outcomes of two operations were analyzed. The propensity score matching (PSM) was performed to reduce potential selection bias.A total of 123 patients with sNF-pNETs were enrolled with 62 males, 69 G1, and median age was 56.91 ± 10.04 years old. During the follow-up period (mean 87 ± 58.1 months), 9(7.32%) disease progressed (recurrence or metastasis) and 2 died (1.62%), 5-years OS was 100%, 5-years DFS was 91.4%. Both lymph node metastasis (p = 0.117) and pathological grade (p = 0.050) were not prognostic factors for sNF-pNETs. The propensity score-matched cohort comprised 27 patients with enucleation and 44 patients with regular pancreatectomy. Enucleation was noninferior to regular pancreatectomy in terms of DFS, before or after PSM. The surgical duration (P 0.01) and blood loss (P 0.01) significantly decreased in enucleation compared with regular pancreatectomy. The other postoperative complications tended to occur in regular pancreatectomy than in enucleation, but no statistically significant difference (all p 0.05).Enucleation seems to be an effective option for the treatment of sNF-pNETs with a lower total rate of postoperative complications and similar long-term prognosis, compared with regular pancreatectomy.

Graphite nanoparticles (GNPs) were introduced into poly(p-phenylene benzobisoxazole) (PBO) matrix to produce composites via in situ polymerisation. Films of various composites were fabricated through the solution casting method in methanesulfonic acid (MSA) with the help of two sand core plates. The interlayer spacing of GNPs increased slightly confirmed by XRD as a result of an expanding effect caused by continuously formed PBO chains between the graphene nanosheets of GNPs during polymerisation. Also, due to the uniform dispersion of GNPs into PBO matrix, composite films exhibited an improved tensile strength (258 MPa, 72% higher than that of pure PBO) with 5 wt% loading of GNPs fillers. The initial decomposition temperature of the composite is ∼630°C. Besides, benefitting from the interfacial polarisation in this conductive filler/polymer system, the dielectric constant of the composites with 10 wt% loading of GNPs reached 6.96, which were over two times higher than that of pristine PBO polymer (2.91).

Lei Zhang,* Yang Lv,* Yefei Rong,* Wenqi Chen, Yuan Fang, Weilin Mao, Wenhui Lou, Dayong Jin, Xuefeng Xu Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai, China *These authors contributed equally to this work Background: The expression and function of the Receptor for Activated C Kinase 1 (RACK1) in cancer growth and metastasis are confused in different cancers, especially in pancreatic ductal adenocarcinoma (PDAC). Methods: One-hundred and eighty-two PDAC tissue specimens (95 males and 87 females) including pancreatic cancer tissue and para-carcinoma tissue were collected for analysis between 2005 to 2012. Blood phenotypic parameters using cell count and capillary electrophoresis were investigated. HE staining, real time PCR, Western blot analysis, and soft agar assays were performed to determine the role of RACK1. Purpose: In this study, we aim to determine the specific role of RACK1 in the untility of PDAC. Results: We found that RACK1 expression was significantly lower in pancreatic cancer tissue than in para-carcinoma normal pancreatic tissue both in clinic and mice with pancreatic cancer at the early stage. Our results suggested that RACK1 silence could significantly promote cell growth and metastasis of pancreatic cancer cells. But we found that the overexpression of RACK1 has the opposite effect in vitro. In vivo MIAPaca-2 cells overexpressing RACK1, the results demonstrated lower metastatic ability than MIAPaca-2 cells. RACK1 overexpression could decrease the NF-κB transactivation activity of MIAPaca-2 cells, which was consistent with the inhibitory effect of RACK1 overexpression on the pro-migration and pro-invasive target gene of NF-κB, while which could be increased by RACK1 silence. RACK1 silence also enhanced protein expression of pro-migration and pro-invasive NF-κB target genes, which on the contrary, could be reversed by IκBα. Besides, RACK1 expression was significantly associated with lymph node metastasis, vessels metastasis, invasion of nerves as well as TNM staging. The 3-year survival rate of patients with high RACK1 expression was significantly higher than those patients with low RACK1 expression. However, RACK1 expression was not an independent risk factor for of the long-term postoperative survival of patients with pancreatic cancer. Conclusion: The obtained results in our study suggested that the low expression of RACK1 was associated with cancer cell growth and metastasis in pancreatic cancer through the activation of the NF-κB pathway. RACK1 could be a potential therapeutic drug target to pancreatic cancer and metastasis. Keywords: receptor for activated C kinase 1, pancreatic cancer, NF-κB, in vivo

Three pairs of bimetallic Schiff base aluminum complexes (1a–6a) with different tetraamine backbone bridging parts and bulky silyl-substituted moieties on salicylidene were synthesized. Using these complexes as catalysts for ring opening polymerisation (ROP) of racemic-lactide (rac-LA), systematical stereoselectivity and kinetic studies on ROP of rac-LA were carried out. The Gibbs free energy difference between homo-propagation and cross-propagation (ΔG≠) calculated by activation entropy and enthalpy showed that bulky substituents at the 3-position enhanced the stereoselectivity. And the kinetic study results indicated that bulkier substituents with more steric hindrance reduced the ROP reactivity. Moreover, these complexes could also be used for copolymerisation of rac-LA and e-caprolactone (e-CL). Copolymers of poly(LA-co-CL) with various monomer ratios were synthesized. Kinetic research on copolymerisation as well as microstructure analysis demonstrated that poly (LA-co-CL) achieved by these complexes were tapered block copolymers.

Aiming to disperse HA nanocrystals in a polymer matrix homogenously, uniform oil-soluble HA nanorods were synthesized via an oleic acid (OA)-assisted mixed-solvent thermal method, and then poly(lactic acid) (PLA)/HA nanorods nanocomposites were fabricated by using a solution method. The HA nanorods with an OA monolayer on the surface dispersed homogeneously in organic solvents and the dispersion in polymer solution was transparent and colloidally stable. TEM images showed that HA nanorods dispersed as single particles without aggregation in PLA matrix. The elongation at break of the composites increased from 4.24% to 8.79% by adding HA nanorods, whereas the tensile strength and Young's modulus were largely unchanged. HA nanorods accelerated evidently the PLA crystallization rate even at a low HA loading and induced a transition to an ordered crystalline morphology confirmed via non-iso/isothermal crystallization, the spherulitic morphology, calculations and wide-angle X-ray diffraction during heating and cooling cycles.

Two types of polylactide–poly(butylene adipate-co-terephthalate)–polylactide (PLA–PBAT–PLA) tri-block copolymers with different molecular weights (CP1 and CP2) were synthesized as compatibilizers for PLA/PBAT blends. Synergistic effects of CP1 and CP2 on the mechanical and rheological properties of the blends have been studied in detail. The addition of small amounts of CP1 and CP2 remarkably increased the elongation at the break point. 0.5 and 0.5 wt% of CP1 and CP2 led to an increase of elongation by over eightfold. Thermal, morphological and rheological analyses showed that addition of CP1 and CP2 increased the miscibility and interfacial bonding strength between PLA and PBAT, in addition to decreasing the melt viscosity. It was thought that the low-molecular-weight compatibilizer CP1 with high mobility would have a positive effect during the transportation of the high-molecular-weight CP2 from the matrix to the interface. In addition, CP2 played a key role in improving the interaction at the interface.

MicroRNAs (miRNAs) are key regulators of diverse biological processes in tumor progression including melanoma. LRIG2 is reported as an oncogene in cancer, however, little is known regarding the molecular and functions of LRIG2 in melanoma. In this study, we reported that LRIG2 expression was higher in melanoma tissues and cell lines and was regulated by miR-149-5p. Furthermore, a luciferase reporter assay and rescue experiment indicated that miR-149-5p directly targeted LRIG2 by binding its 3'UTR. The overexpression of miR-149-5p significantly suppressed melanoma cell proliferation, colony formation, and promoted cell apoptosis. These results suggest that miR-149-5p acts as a suppressing molecule and may be a good method for melanoma therapy.

A newly synthesized aromatic sulfonate compound, complex 2 with formula of K2[H3COOC-C6H3(SO3)2]·2H2O(methyl 3,5-disulfo-benzoate dipotassium dihydrate) was synthesized and characterized by elemental analysis, infrared(IR) spectrometry, nuclear magnetic resonance(NMR) and crystal structure measurement. Single-crystal X-ray diffraction(XRD) revealed that complex 2 crystallized in the triclinic system with space group $$P_{\bar 1}$$ . Complex 2 was used as nucleating agent for poly(L-lactide)(PLLA). The crystallization of PLLA with powder of complex 2 was investigated by means of differential scanning calorimetry(DSC) and polarized optical microscopy (POM). The results prove that complex 2 was effective as nucleating agent for PLLA. It could accelerate crystallization by reducing the induction time and increasing the density of nuclei in the crystallization process. The half-time of crystallization(t 0.5) for pure PLLA was about 8 times longer than that of PLLA sample with 1.0%(mass fraction) of complex 2.