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Moisture and salt content of soil are the two predominant factors influencing its shear strength. This study aims to investigate the effects of these two factors on shear strength behavior of loess in the Xining Basin of Northeast Qinghai-Tibet Plateau, where such geological hazards as soil erosion, landslides and debris flows are widespread due to the highly erodible loess. Salinized loess soil collected from the test site was desalinized through saltleaching in the laboratory. The desalinized and ovendried loess samples were also artificially moisturized and salinized in order to examine how soil salinity affects its shear strength at different moisture levels. Soil samples prepared in different ways (moisturizing, salt-leaching, and salinized) were measured to determine soil cohesion and internal friction angle. The results show that salt-leaching up to 18 rounds almost completely removed the salt content and considerably changed the physical components of loess, but the soil type remained unchanged. As salt content increases from 0.00% to 12.00%, both the cohesion and internal friction angle exhibit an initial decrease and then increase with salt content. As moisture content is 12.00%, the salt content threshold value for both cohesion and internal friction angle is identified as 3.00%. As the moisture content rises to 16.0% and 20.00%, the salt content threshold value for cohesion is still 6.00%, but 3.00% for internal friction angle. At these thresholds soil shear strength is the lowest, below which it is inversely related to soil salinity. Beyond the thresholds, however, the relationship is positive. Dissimilar to salinity, soil moisture content exerts an adverse effect on shear strength of loess. The findings of this study can provide a valuable guidance on stabilizing the engineering properties of salinized loess to prevent slope failures during heavy rainfall events.

This study aims to assess the hydrological effects of four herbs and four shrubs planted in a selfestablished test area in Xining Basin of northeastern Qinghai-Tibet Plateau, China. The Rainfall-Intercepting Capability (RIC) of the herbs and shrubs was evaluated in rainfall interception experiment at the end of the third, fourth and fifth month of the growth period in 2007. The leaf transpiration rate and the effects of roots on promoting soil moisture evaporation in these plants were also assessed in transpiration experiment and root-soil composite system evaporation experiment in the five month’s growth period. It is found that the RIC of the four studied herbs follows the order of E. repens, E. dahuricus, A. trachycaulum and L. secalinus; the RIC of the four shrubs follows the order of A. canescens, Z. xanthoxylon, C. korshinskii and N. tangutorum. The RIC of all the herbs is related linearly to their mean height and canopy area (R2 ≥ 0.9160). The RIC of all the shrubs bears a logarithmic relationship with their mean height (R2 ≥ 0.9164), but a linear one with their canopy area (R2 ≥ 0.9356). Moreover, different species show different transpiration rates. Of the four herbs, E. repens has the highest transpiration rate of 1.07 mg/(m2·s), and of the four shrubs, A. canescens has the highest transpiration rate (0.74 mg/(m2·s)). The roots of all the herbs and shrubs can promote soil moisture evaporation. Of the four herbs, the evaporation rate of E. repens root-soil composite system is the highest (2.14%), and of the four shrubs, the root-soil composite system of A. canescens has the highest evaporation rate (1.41%). The evaporation rate of the root-soil composite system of E. dahuricus and Z. xanthoxylon bears a second-power linear relationship with evaporation time (R2 ≥ 0.9924). The moisture content of all the eight root-soil composite systems decreases exponentially with evaporation time (R2 ≥ 0.8434). The evaporation rate and moisture content of all the plants’ root-soil composite systems increases logarithmically (R2 ≥ 0.9606) and linearly (R2 ≥ 0.9777) with root volume density. The findings of this study indicate that among the four herbs and four shrubs, E. repens and A. canescens possess the most effective hydrological effects in reducing the soil erosion and shallow landslide in this region.

In order to improve convergence rate and optimization precision of the cuckoo search (CS) algorithm, an improved dynamic self-adaption cuckoo search algorithm based on collaboration between subpopulations (SC-DSCS, where ‘SC’ represents ‘Subpopulation Collaboration,’ ‘DS’ represents ‘dynamic self-adaption’) is proposed. In SC-DSCS, the population of cuckoos is divided into two subgroups. The nest locations of birds belonging to the first subgroup are updated according to the traditional CS algorithm so as to retain the global search ability, and the second subgroup produces the corresponding nest locations for next generation by flying from the better nest locations to enhance the local search ability of the CS algorithm. Through collaboration between two subgroups, the problem that the local search ability of CS algorithm is not strong can be effectively solved. In order to reduce the probability of the algorithm falling into local optimum and improve the optimization precision, the SC-DSCS algorithm creates a new bird’s nest under the comprehensive assessment of the first three best bird’s nests. The new nest is added to the optimal bird’s nest sequence. In order to improve the adaptability of the SC-DSCS, adaptive step length control is adopted in the bird’s nest position updating process. Finally, nine benchmark functions are adopted to carry out the simulation experiments. The proposed algorithm is compared with particle swarm optimization algorithm, artificial colony algorithm and differential evolution algorithm. Simulation results show that the proposed SC-DSCS algorithm has better convergence speed and optimization precision.

The grey wolf optimizer (GWO) is a novel type of swarm intelligence optimization algorithm. An improved grey wolf optimizer (IGWO) with evolution and elimination mechanism was proposed so as to achieve the proper compromise between exploration and exploitation, further accelerate the convergence and increase the optimization accuracy of GWO. The biological evolution and the “survival of the fittest” (SOF) principle of biological updating of nature are added to the basic wolf algorithm. The differential evolution (DE) is adopted as the evolutionary pattern of wolves. The wolf pack is updated according to the SOF principle so as to make the algorithm not fall into the local optimum. That is, after each iteration of the algorithm sort the fitness value that corresponds to each wolf by ascending order, and then eliminate R wolves with worst fitness value, meanwhile randomly generate wolves equal to the number of eliminated wolves. Finally, 12 typical benchmark functions are used to carry out simulation experiments with GWO with differential evolution (DGWO), GWO algorithm with SOF mechanism (SGWO), IGWO, DE algorithm, particle swarm algorithm (PSO), artificial bee colony (ABC) algorithm and cuckoo search (CS) algorithm. Experimental results show that IGWO obtains the better convergence velocity and optimization accuracy.

As twinning-induced plasticity (TWIP) steel is one potential material for shaped charge liner due to the combination of high strength and high plasticity, deformation mechanism at high strain rate and high temperature is required to study. Compression experiments of Fe-30Mn-3Si-4Al TWIP steel were conducted using a Gleeble-1500 thermal simulation machine and a split-Hopkinson pressure bar (SHPB) between 298 and 1073 K at strain rates of 10−3 and 700 s−1, respectively. Microstructures were observed using optical microscopy (OM) and transmission electron microscopy (TEM). Results show that flow stress and densities of deformation twins and dislocations decrease with increasing deformation temperature at strain rates of 10−3 and 700 s−1. The stack fault energy (SFE) values (Γ) of Fe-30Mn-3Si-4Al TWIP steel at different temperatures were calculated using thermodynamic data. Based on corresponding microstructures, it can be inferred that at 700 s−1, twinning is the main deformation mechanism at 298–573 K for 30 mJ/m2⩽Γ⩽63 mJ/m, while dislocation gliding is the main deformation mechanism above 1073 K for Γ⩾ 145 mJ/m2. In addition, with increasing strain rate from 10−3 to 700 s−1, the SFE range of twinning is enlarged and the SEF value of twinning becomes higher.

This study aimed to investigate the factors associated with the health behavior of hypertensive elderly patients. This cross-sectional survey used a general data scale, a health conception scale, a scale for self-rated abilities for health practice, and health-promoting lifestyle profiles to investigate the health behavior of hypertensive elderly patients from clinical check-up to hospitalization. The health behavior score of hypertensive patients was 72.25 ± 16.66, and 23.8 % of the patients had high scores. The health-promotion score was positively correlated with those of health conception, self-efficacy, and education level, but negatively correlated with that of unhealthy habits (P

To investigate the clinicopathologic significance and predictive value of Bmi-1 expression in patients with colon cancer. Bmi-1 expression was assessed by immunohistochemistry, PCR, and western blotting in specimens from 203 patients and by immunohistochemistry in 66 specimens of lymph node metastasis (LNM). Positive staining of Bmi-1 occurred in 7.9% (16/203), 66.5% (135/203), and 86.4% (57/66) of specimens from normal tissue, colon cancer, and LNM, respectively. Staining was significantly correlated with clinical stage, depth of invasion, nodal involvement, distant metastasis, and Ki67 level. Bmi-1 was upregulated at the transcriptional and translational levels. Patients with Bmi-1-positive localized tumors had a much lower 5-year disease-free survival (relative risk 2.919, P

Insulin-like growth factor-II mRNA-binding protein 3 (IMP3) plays a vital role in carcinogenesis; however, its significance and prognostic value in colon cancer remain unclear.In this study, a tissue microarray (TMA) containing 203 samples of primary colon cancer was assessed for IMP3 expression by immunohistochemistry. The TMA included 66 lymph node metastasis (LNM) samples. The mRNA and protein expression levels of IMP3 were evaluated by reverse transcription-PCR and Western blot analysis, respectively.Cytoplasmic immunoreactivity of IMP3 was significantly higher in LNM (93%) than in primary colon cancer (65%) or normal mucosa (3.9%). Increased IMP3 levels were significantly correlated with higher clinical stage, T classification, LNM, presence of distant metastasis, and Ki-67 positivity. IMP3 was up-regulated in colon cancer compared with paired normal colonic mucosa. IMP3 expression was associated with an 11-fold increased risk of distant metastases (hazard ratio (HR) 10.7; 95% confidence interval (CI) 3.3-34.5; P0.0001). Patients with IMP3-positive localized tumors had lower 5-year disease-free survival (DFS) (HR 2.87; 95% CI 1.65-4.98; P0.0001) and overall survival (OS) (HR 4.2; 95% CI 2.51-10.17; P0.0001) than those with IMP3-negative tumors. Multivariate survival analysis showed that IMP3 was an independent prognostic marker for DFS (HR 1.92; 95% CI 1.06-3.47; P = 0.03) and OS (HR 2.37; 95% CI 1.2-4.7; P = 0.014).IMP3 may play an important role in colon cancer progression and could serve as a prognostic biomarker to identify patients at risk of developing metastasis or recurrence after colonectomy.