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CFIRL is a long noncoding RNA (lncRNA), we previously identified as the most significantly upregulated lncRNA in the failing hearts of patients with dilated cardiomyopathy (DCM). In this study, we determined the function of CFIRL and its role in DCM. Real-time polymerase chain reaction and in situ hybridization assays revealed that CFIRL was primarily localized in the nucleus of cardiac fibroblasts and robustly increased in failing hearts. Global knockdown or fibroblast-specific knockout of CFIRL attenuated transverse aortic constriction (TAC)-induced cardiac dysfunction and fibrosis in vivo. Overexpression of CFIRL in vitro promoted fibroblast proliferation and aggravated angiotensin II-induced differentiation to myofibroblasts. CFIRL knockdown attenuated these effects. Mechanistically, RNA pull-down assay and gene expression profiling revealed that CFIRL recruited ENO1, a newly identified noncanonical transcriptional factor, to activate IL-6 transcription. IL-6 exerted a paracrine effect on cardiomyocytes to promote cardiac hypertrophy, which can be prevented by CFIRL knockdown. These findings uncover the critical role of CFIRL, a fibroblast-associated lncRNA, in heart failure by facilitating crosstalk between fibroblasts and cardiomyocytes. CFIRL knockdown might be a potent strategy to prevent cardiac remodeling in heart failure, particularly in DCM. [ABSTRACT FROM AUTHOR]

Based on data obtained from ERA-20C during 1900–2010, this study statistically conducts spatiotemporal characteristics and relations between boundary layer height (BLH) and aridity index (AI) in East Asian drylands, thus originally understanding dry–wet changes from perspective of atmospheric boundary layer. A high (low) BLH generally coincides with regions that have small (large) AI. The annual variability of BLH and AI is negatively correlated with correlation coefficients of − 0.469, − 0.880, and − 0.947 for hyper-arid, arid, and semiarid regions, respectively. This correlation is followed in 61.3, 55.9, and 55.9% of years, whereas in 12.6, 8.1, and 9.9% of years the changes in BLH are in advance of the changes in AI for hyper-arid, arid, and semiarid regions, respectively. The BLH and area of East Asian drylands have a positive correlation coefficient of 0.651. These results indicate that there is a connection between changes in BLH and dry–wet changes in the climate of arid regions, confirming the changes in BLH drive dry–wet changes. [ABSTRACT FROM AUTHOR]

Many researchers have been searching for the alternative for natural river sand as fine aggregate for concrete preparation. Thus, whether it is feasible to replace natural river sand by aeolian sand in concrete partially or totally is studied. At the macroscale, a universal testing machine and concrete rapid freeze-thaw equipment are applied in testing mechanical properties as well as frost resistance durability, respectively. At the mesoscale, a scanning electron microscope has been taken for observing and analyzing the interfacial transition zone in aeolian sand concrete. At the microscale, nuclear magnetic resonance is used for testing pore structure evolution. Simultaneously, the macro- and microrelationships between compressive strength and total and interval porosities are established. The grey correlation model is adopted to analyze the main microscopic pore parameters that affect aeolian sand concrete's frost resistance durability. Results show that the workability and mechanical properties of aeolian sand concrete first increase and subsequently reduce as aeolian sand content increases, and the optimum content is 30%. The influence mechanism is that aeolian sand particles with different contents change the linear packing density of fine aggregate and affect the aggregate gradation and pore structure. The compressive strength has a negative linear relation to total porosity and porosity of more harmful pores (>200 nm) and an insignificant correlation with the porosity of non-more harmful pores (<200 nm). A medium and low content of aeolian sand (10%–60%) partly improves concrete frost resistance, whereas a large content (80%–100%) significantly improves concrete frost resistance. Grey correlation analysis shows the most important microstructural factor influencing the macroscopic frost resistance durability in aeolian sand concrete should be the relative proportion of more harmful and harmless pores. The findings of this research expand aeolian sand concrete's application in cold areas and provide a new way for the reuse of waste resources. [ABSTRACT FROM AUTHOR]

As a completed decomposed product of granite rock, the granite residual soil widely distributes in South China with a special soil structure that can be easily damaged under external disturbance. Therefore, studying the evolution of soil cracks during the loading process is important for engineering practice that needs to evaluate the soil shear strength, such as slope stability analysis. The purpose of this study is to investigate the micro-structure for the intact granite residual soil under external loading base on X-ray computed tomography (CT) through global and local scanning (with resolutions of 180 µm and 26.7 µm, respectively). The micro-structural evolution of the cross-sections of soil column extracted from a granite residual soil layer under axial loading was investigated by CT scanning with a 0.5 mm slice thickness. The number of cracks (including macro-cracks and meso-cracks), area ratios and porosity corresponding to varying loading stages (initial, peak-stress and failure) were analyzed based on the cross-sectional CT images. Test results shows that the structure strength of the soil was mainly subject to macro-cracks. In addition, the increase of the porosity is mainly attributed to the generation and expansion of the cracks along sandy particle under external loading. This study can provide theoretical support and data support for understanding the micro-structural evolution of granite residual soil that is commonly encountered in civil engineering. [ABSTRACT FROM AUTHOR]

Natural soils usually experience multiple drying and wetting cycles in geotechnical engineering. In this paper, the influences of history of drying and wetting upon the desorption and adsorption soil–water retention curve (SWRC) of silicon micro-powder (SMP) and Guangxi Guiping clay (GGC) are examined and discussed. The experimental results presented are obtained by using an improved pressure-plate instrument. The results show that the size of the hysteresis loops decreases with increasing drying–wetting cycles, and these are almost identical after 4 drying–wetting cycles. In addition, the all drying–wetting curves are best fitted by VGM model, and the estimated drying air-entry value reduces with the drying number and remains almost unchanged in the fourth and fifth drying. On the contrary, the wetting estimated air-entry value increases with the wetting number and tends to a stable value. [ABSTRACT FROM AUTHOR]

Predictive models have been widely used in different engineering fields, as well as in petroleum engineering. Due to the development of high-performance computer systems, the accuracy and complexity of predictive models have been increased significantly. One of the common methods for prediction is artificial neural network (ANN). ANN models in combination with optimization algorithms provide a powerful and fast tool for the prediction and optimization of processes which take a large amount of time if they are simulated using common simulation technics. In the present paper, to predict penetration rate during drilling process, several ANN models were developed based on the data obtained from drilling of a gas well located in south of Iran. Regarding the R2 and RMSE values of the developed models, the best model was selected for prediction of penetration rate. In the next step, artificial bee colony algorithm was used for optimization of the parameters which are effective on rate of penetration (ROP). Results showed that the model is accurate enough for being used in the prediction and optimization of ROP in drilling operations. [ABSTRACT FROM AUTHOR]

The cutting efficiency and wear of tunnel boring machine (TBM) cutters are two important parameters commonly used to estimate the boring performance and lifetime of the TBM in the tunneling process. These problems have been investigated by several researchers, whereas the influence of jointed rock mass and mixed ground condition on the cutting efficiency and cutter wear remains insufficiently understood. This study aims to elucidate the influence of rock mass and ground parameters on the cutting efficiency and cutter wear of the TBM by conducting a series of newly developed rolling boring tests on prefabricated joint sandstone samples with different orientations, spacings, and interlayers. Moreover, a numerical simulation is implemented through ANSYS software to verify the rationality of experimental results. The experimental and numerical results indicate that the optimal joint orientation is 30° for the TBM to intrude into a jointed rock mass. As joint spacing increases, the cutting efficiency decreases and the cutter wear increases. Furthermore, specific energy (SE) and cutter wear simultaneously reach their maximum values when the rock abrasivity index (RAI) is 60. Both the specific energy and cutter wear decrease with increasing specific strength. For the rock mass with a soft interlayer in mixed ground, the optimal dip angle is 45°. Additionally, the fitting formulas of SE and cutter wear in mixed ground are proposed to quantitatively illustrate the effect of RAI and interlayer strength on the cutting efficiency and cutter wear. The present study provides an improved understanding of rock-breaking mechanics, thereby making it possible for designers to adjust their design to enhance the TBM cutting efficiency. [ABSTRACT FROM AUTHOR]

This paper proposes a new comprehensive control strategy to precisely control a piezoelectric positioner by combining discrete-time sliding mode control (DSMC) with the Prandtl-Ishlinskii hysteresis model. In order to obtain precision tracking control, a direct inverse hysteresis compensation method is firstly adopted to compensate for the asymmetric hysteresis nonlinearity. Due to the existence of hysteresis modeling error, the dynamics behavior of the piezoelectric positioner with hysteresis compensation can be treated as a linear second order plant plus an unknown lumped disturbance term. Then a discrete-time sliding mode controller with a disturbance observer is designed to stabilize the position error and improve the position accuracy. The stability of DSMC and the convergence of the disturbance observer are both carried out. It is shown that the tracking performances are robust to the parametric uncertainties and unknown disturbances. Eventually, different trajectory-tracking experiments are performed, and the comparative experimental results are presented to confirm the significantly better performance of the proposed control strategy. [ABSTRACT FROM AUTHOR]

In this paper, chalcopyrite CuFeS with sheet-like or rod-like morphology has been synthesized by solvothermal reaction route in the presence of poly(vinylpyrrolidone) (PVP). The concentration of PVP has significant influences on the morphology of CuFeS nanocrystals. With the increasing concentrations of PVP, the sheet morphology of CuFeS becomes more uniform. Meanwhile, the average dimensions of CuFeS sheets are reduced and small CuFeS nanoparticles are clearly decreased. When the molar ratio of CuFeS to PVP is 1:2, the shape of CuFeS changes to rod-like, which is composed of CuFeS sheets. Considering the influence of uniformity and shape of CuFeS nanocrystals, the CuFeS nanocrystals with different molar ratios of PVP have been used as active component to prepare anode for Li-ion batteries. The Li-ion battery using CuFeS nanocrystals with the molar ratio of 1:2 to PVP shows the highest reversible specific capacity of ~519 mAh/g after 50 cycles at a current density of 100 mA/g and maintains a specific capacity of ~400 mAh/g at a density of 1000 mA/g. The results demonstrate that the PVP-assisted CuFeS electrodes are promising candidates for use as Li-ion batteries. [ABSTRACT FROM AUTHOR]

The strain distributions near the interface when the elbow steel fiber is pulled out from the half-mould concrete matrix are directly measured using a combined method of single fiber pull-out test and digital image correlation. Meanwhile, the real-time processes of the bonding, debonding and sliding at the interface are observed. The micro-mechanism of the strain localization in the failure process of interface when debonding occurs and the strengthening mechanism at the imbedded fiber are discussed. The experimental results show that the meso-scale strain localization gives rise to the localization of shear damage near the fiber interface. This strain localization characterized by the debonding process near the interface occurs, develops and moves gradually at an apparently regular interval. At the elbow part of the imbedded fiber, the peak value of the shearing stress occurs. But the primary debonding does not occur at this place because the strength of the shear damage is increased at the local area of the elbow part in the concrete, displaying an apparent reinforced effect at the end of the fiber. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented on the nanochemical properties of dragonfly Anax parthenope julius Brauer in the March 24, 2007 issue.

The original article can be found online. [ABSTRACT FROM AUTHOR]

Experimental investigations on the impact of multiple drying-wetting cycles on mechanical behaviour of unsaturated soils, particularly on shear behaviour, are limited. Suction-controlled direct shear tests were carried out to investigate the impact of multiple drying-wetting cycles on shear behaviour of an unsaturated compacted clay. One drying-wetting cycle was applied on a soil specimen by increasing its suction to 400 kPa followed by returning its suction to 1 or 200 kPa at constant vertical stress. The experimental results showed that more significant volume contraction occurred during the first drying-wetting cycle as compared with the subsequent drying-wetting cycles. At higher net normal stress (i.e. 200 kPa), a transition from shear-induced contraction to dilation was found. Nevertheless, such transition from contraction to dilation was not observed for the specimens at lower net normal stress (i.e. 50 kPa). The results also showed that amplitude of drying-wetting cycles and vertical stress influences the shear strength. The shear strength increases slightly after the first drying-wetting cycle at lower net normal stress; at higher net normal stress the effect of the first cycle on the shear strength is contrast. [ABSTRACT FROM AUTHOR]