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As demand for energy increases, the number of "three-high" (high-pressure, high-yield, high-sulfur) gas Wells has doubled, the severe stress fluctuation of pipe string caused by downhole high-pressure environment leads to the failure of rope fracture is particularly prominent. It is easy to cause pipeline blockage and large amount of high-pressure toxic gas leakage caused by tool string accidental falling. Therefore, based on the theory of Love and elastoplastic contact theory, and considering the influence of Poisson's ratio effect, this article establishes a calculation model for tensile fatigue of interaction between rope strands to study the influence of key structural parameters and breaking wire position on stress distribution and fatigue life of rope. The results show that: the core strand of the rope is the main force position, the overall stress shows the trend of decreasing with the increase of winding radius; when the rope is stretched, the axial deformation near the core of the rope is smaller than the deformation far from the core; under the same number of broken wires, the fatigue life of different ropes is related to the location of broken wires, the farther the location of broken wires from the core of the rope, the higher the fatigue life. The research work in this article provides theoretical guidance for the safe operation of ropes in "three-high" gas wells. [ABSTRACT FROM AUTHOR]

It is a novel therapeutic strategy to suppress tumour growth and metastasis by regulating the interaction between bioactivity ions and the biological process of tumour cells. This study synthesised a mesoporous hydroxyapatite (MHAP)-based nanocarrier for targeted delivery of the anti-cancer drug doxorubicin (DOX). To further strengthen the targeting of DOX-loaded nanocarrier to tumour, HA that could specifically identify receptor on the surface of tumours was functionally modified. The drug release properties curve showed that the MHAP-HA@DOX complex showed pH-sensitive and sustained release properties. Also, the MHAP-HA@DOX complex represented high toxicity against lung cancer A549 cells. Besides, it displayed a significant inhibitory effect on tumour growth rate in tumour-bearing mice, while no evident toxicity for mice was observed. This nano-material is hoped to be an effective and novel nano-drug for lung cancer. [ABSTRACT FROM AUTHOR]

Purpose:Actin-binding protein capping protein gelsolin-like (CapG) was preferentially expressed in human pulmonary arterial smooth muscle cells (PASMCs) under hypoxia, and reduced CapG expression was accompanied by impaired migration ability in vitro. We intended to investigate the effects of CapG on rat PASMCs and hypoxia-induced pulmonary hypertension (HPH) rat model.Materials and Methods:We investigated the effect of RNA interference-medicated down-regulation of CapG expression in rat PASMCs as well as in HPH rat model. The proliferation, apoptosis and cell cycle of PASMCs were evaluated. The HPH rat model was established by intratracheal instillation of lentiviral vector and subsequent hypoxia exposure for four weeks. Right ventricular systolic pressure, right ventricular hypertrophy and the percentage of medial wall thickness were measured to evaluate the development of HPH.Results:Knock-down CapG in PASMCs resulted in decreased proliferation, increased apoptosis and induced cell cycle inhibition. Down-regulation of CapG expression locally could attenuate pulmonary hypertension, pulmonary vascular remodeling and right ventricular hypertrophy in HPH rat model.Conclusions:Our study indicated that CapG participated in the pathogenesis of pulmonary vascular remodeling in HPH rats, which was probably mediated by promoting the proliferation and inhibiting the apoptosis of PASMCs. We proposed CapG modulating protective effects of pulmonary hypertension. [ABSTRACT FROM AUTHOR]

Poly(ether-b-amide) (PEBA)/Tween20 gel membranes containing from 0 wt% to 65 wt% of Tween20 in PEBA2533, PEBA3533, and PEBA4033 were prepared by solvent casting method for CO2/N2separation. The gas separation properties of the polymeric gel membranes were tested for single gases of CO2and N2at 25°C with the feed pressure of 0.6 atm. For all pure PEBA membranes, CO2and N2permeability decreased as the amount of polyamide block increased, but CO2/N2selectivity increased. For PEBA/Tween20 gel membranes, both the CO2permeability and CO2/N2selectivity were greatly enhanced with the increase of Tween20 content. For the membrane of PEBA4033/Tween20-65, CO2/N2selectivity, and CO2permeability reached 54 and 146 Barrer, respectively, which is very interesting for potential application in CO2removal from flue gas. [ABSTRACT FROM PUBLISHER]

ZIF-8-filled polydimethylsiloxane (PDMS) membranes, PDMS/ZIF-8, were prepared by a two-step polymerization process and were used to recovern-butanol from an aqueous solution by pervaporation (PV). Compared with pure PDMS membrane, PDMS/ZIF-8 membranes demonstrated an obviously highern-butanol permselectivity. As an increase of ZIF-8 content,n-butanol/water selectivity increased initially and then decreased, while then-butanol and water permeability decreased monotonously. PDMS/ZIF-8 membrane containing 2 wt% ZIF-8, that is, PDMS/ZIF-8-2 showed the highest selectivity. On the other hand, selectivity and permeability forn-butanol and water of PDMS/ZIF-8-2 membrane decreased with the increase of operating temperature. The selectivity and permeability forn-butanol reached 7.1 and 3.28 × 105barrer, respectively, at 30°C when the feed concentration ofn-butanol was 0.96 wt%. [ABSTRACT FROM AUTHOR]