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The characteristics of non-connected pores of four Longmaxi shale samples from the southern Sichuan Basin of China were investigated from the studies of pore size distribution (PSD), pore volumes, pore types using helium pycnometry [gas injection porosimetry (GIP) and GRI (Gas Research Institute) method], nuclear magnetic resonance (NMR), nuclear magnetic resonance cryoporometry (NMRc), and spontaneous water and oil imbibition experiments. GRI porosity on particle sizes less than 5 mm sample and a 2 MPa helium injection pressure provides information on the total porosity, including both non-connected and connected pores. GIP porosity using core plugs only measures connected pores which extend to the surface of the sample accessible by helium. So the difference between GRI and GIP porosities is used to estimate the volumes of non-connected pores. And the volumes of non-connected pores accounts for 17.5%–40.3% of the total pore volume. For NMRc test results, total pore volume increases with sample size decrease, and the great difference of pore volume with a pore diameter range from 5 nm to 31 nm between small cylinder sample and 0.15–0.075 mm crushed sample is caused by non-connected pores opened. With a decrease of length for cubic samples, the increase in volume and rate of oil imbibition is greater than that of water imbibition, indicating that the non-connected pores are considered to be mainly oil-wet. In addition, the percentage of non-connected pores has a good correlation with TOC (total organic carbon) content. Therefore, this evidence implies that non-connected pores are mainly within the organic matter. NMR tests at different drying temperatures and a NMRc experiment provide a quantitative classification of the shale pore system which indicates that the exploitable pore diameters are larger than 4.25 nm. So non-connected pores with a diameter of 5–31 nm could be effectively exploited if connected by fracturing. The more the non-connected pores are opened, the better the pore connectivity of shale reservoir will be, with a less possibility of water blocking. In the process of shale gas development, attention should be paid to the interaction between fracturing fluid and rock components in order to release more non-connected pores. Therefore, to increase shale gas extraction efficiency, more effort should be directed towards identifying natural, and creating induced, porosity. • Non-connected pore fractions of the studied shale are obtained from complementary approaches. • The shale pore system was quantified using NMR and NMRc methods, with measurable pore diameters down to 4.25 nm. • Non-connected pores, which are mainly in organic matter, constitute 17–40% of total pore volume and have diameters of 5~31 nm. [ABSTRACT FROM AUTHOR]

As evolutionarily conserved organelles, lipid droplets (LDs) carry out numerous functions and have various subcellular localizations in different cell types and species. In avian cone cells, there is a single apically localized LD. We demonstrated that CIDEA (cell death inducing DFFA like effector a) and microtubules promote the formation of the single LD in chicken cone cells. Centrins, which are well-known centriole proteins, target to the cone cell LD via their C-terminal calcium-binding domains. Centrins localize on cone cell LDs with the help of SPDL1-L (spindle apparatus coiled-coil protein 1-L), a previously uncharacterized isoform of the kinetochore-associated dynein adaptor SPDL1. The loss of CETN3 or overexpression of a truncated CETN1 abrogates the apical localization of the cone cell LD. Simulation analysis showed that multiple LDs or a single mispositioned LD reduces the light sensitivity. Collectively, our findings identify a role of centrins in the regulation of cone cell LD localization, which is important for the light sensitivity of cone cells. [Display omitted] • Centrins and microtubules regulate chicken cone cell LD dynamics • SPDL1 facilitates the localization of centrins on cone cell LDs • Centrins regulate the apical localization of LDs in cone cells • Changes in the number or position of LDs reduce the optical sensitivity of cone cells Pan et al. find that centrins localize to chicken cone cell lipid droplets with the help of SPDL1-L, a previously uncharacterized long isoform of SPDL1. Centrins and SPDL1-L regulate the apical localization of lipid droplets in cone cells. [ABSTRACT FROM AUTHOR]

This investigation was primarily to establish assessment criteria for axial fluctuations of head sheaves in a multi-rope friction mine hoist. Large axial fluctuating displacements of head sheaves can excite intense transverse vibrations in inclined ropes, which can result in dangerous collision between two adjacent ropes. A coupled dynamic model was established and then validated by experimental tests and numerical simulations. In this case, it can be concluded that double rotational frequency of head sheave is the primary excitation frequency and rope tension can change the resonance frequency range. Finally, to avoid large transverse displacements of inclined ropes in a multi-rope friction hoist, based on response–excitation displacement curves, assessment criteria for axial fluctuating displacements of head sheaves were established. [ABSTRACT FROM AUTHOR]

• The calculation equation with correction efficient and particle swarm optimization can improve the inversion accuracy of compressive modulus of the bottom aquifer. • The variation law of the elastoplastic interface of the vertical additional force with the bottom aquifer waterhead is deduced. • The interaction between the shaft and guide rail changes with the guide rail position due to the vertical additional force acting on the shaft. • The guide rail deformation can reflect the deformation trend of the shaft and the connection state between them under non-mining action. To lay the foundation for monitoring the mine vertical shaft deformation and mitigating its influence on the guide rail, this paper studies the deformation law of the guide rail and its interaction mechanism with the shaft under non-mining action. Firstly, the correction coefficient is introduced into the settlement equation, and its compression modulus is inverted by the particle swarm optimization (PSO). Secondly, the relationship between the elastoplastic interface of the vertical additional force (VAF) and the bottom aquifer (BA) water head is deduced, and then its distribution law varied with water head is obtained. Finally, a finite element model using spring elements to simplify the interaction between the shaft and surrounding rock-soil body is established to analyze the shaft deformation law, its interaction mechanism with the guide rail, and the guide rail deformation rule in different connection states. It can be obtained from the analysis results that using the improved settlement equation as the PSO objective function weakens the influence of compressive modulus with the change of soil settlement, and enhances the calculation precision on the BA settlement, so that the deduced relationship between the bottom aquifer water head and the elastoplastic interface of the VAF is consistent with the actual soil settlement and deformation laws. The spring element can effectively simulate the interaction between the shaft and rock-soil body, which makes the action mechanism between them to consistent with the actual situation. Owing to the vertical compression deformation of the shaft, the force direction on the guide rail subjected to the shaft varies with the position, which bears the vertical upward force in the upper section, the vertical downward force in the middle section and the vertical upward force in the lower section. There are obvious differences in the deformation laws of the guide rail corresponding to different connection states, disconnected positions and non-mining shaft deformation, which exist a certain regularity corresponding their respective states. The guide rail mainly produces the fluctuating deformation along the bunton direction, and its amplitude and range increase with the non-mining shaft deformation. All in all, the guide rail deformation can reflect the state of itself, the shaft and the connection between them, which can provide reference and guidance for the monitoring of the shaft deformation and the safety of the mine hoisting system. [ABSTRACT FROM AUTHOR]