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Purpose: Adhesion between calcium oxalate crystals and renal tubular epithelial cells is a vital cause of renal stone formation; however, the drugs that inhibit crystal adhesion and the mechanism of inhibition have yet to be explored. Methods: The cell injury model was constructed using nano-COM crystals, and changes in oxidative stress levels, endoplasmic reticulum (ER) stress levels, downstream p38 MAPK protein expression, apoptosis, adhesion protein osteopontin expression, and cell–crystal adhesion were examined in the presence of Laminarin polysaccharide (DLP) and sulfated DLP (SDLP) under protected and unprotected conditions. Results: Both DLP and SDLP inhibited nano-COM damage to human kidney proximal tubular epithelial cell (HK-2), increased cell viability, decreased ROS levels, reduced the opening of mitochondrial membrane permeability transition pore, markedly reduced ER Ca2+ ion concentration and adhesion molecule OPN expression, down-regulated the expression of ER stress signature proteins including CHOP, Caspase 12, and p38 MAPK, and decreased the apoptosis rate of cells. SDLP has a better protective effect on cells than DLP. Conclusions: SDLP protects HK-2 cells from nano-COM crystal-induced apoptosis by reducing oxidative and ER stress levels and their downstream factors, thereby reducing crystal–cell adhesion interactions and the risks of kidney stone formation. [ABSTRACT FROM AUTHOR]

In this paper, the influence of steel rate and substitution rate of iron tailing powder on the bearing capacity of the stub columns is mainly investigated through the test of five concrete stub columns under axial compression loading with square steel tube self-compacting iron tailing, and the test bearing capacity is compared with the bearing capacity calculated by each code. The test results show that the bearing capacity of the test piece increases obviously with the increase of the steel content; the bearing capacity of the test piece is less affected by the substitution rate of iron tailing powder; it is suggested to use code GB50936-2014 to design and calculate the bearing capacity of the stub column under axial compression loading.

In order to associate with using acoustic emission, ultrasonic or other means to locate damage of concrete, based on the concrete CT image information, the research of 3D reconstruction of concrete crack structure was completed by using Amira 5.2.1 3D reconstruction software. Experiments showed that: three dimensional reconstruction of concrete can reflect the real crack structure, and distribution of aggregate concrete of three dimensional model established was basically in accordance with the original CT image, which laid the good foundation to simulate and analysis by using ANSYS finite element software in the future.

CT is one of the effective means to analyze concrete meso-damage. Based on CT image under uniaxial compression, this paper used Amira—three-dimensional reconstruction software to segment the images, extract pores, count and calculate the pore volume .This paper analyzed the corresponding relation between pressure—pore volume diagram and pressure—displacement diagram under cyclic loading. The results showed that: under uniaxial loading condition, pore volume change can be used to describe the change of the meso pore of the concrete specimen, including compaction, initiation, extension and perforation.

Objectives: It is well known that sleep quality was associated with falls. This study aimed to examine whether the presence of depressive symptoms mediate the association of self-reported sleep quality with falls. Methods: Data of community-based study including 4,579 adults aged 60 years or older were analyzed. Information regarding sleep quality and falls was self-reported by participants using pre-designed questionnaires. The nine-item Patient Health Questionnaire (PHQ-9) without the sleep item was used to assess the presence of depressive symptoms. A bootstrapping approach was performed to explore whether the relationship between self-reported sleep quality and falls was partially mediated by depressive symptoms. The mediator was considered significant if the 95% confidence interval (CI) did not include 0. Results: Older adults with poor sleep quality had higher odds of falls than their counterparts with normal sleep. In the equation regressed falls on self-reported sleep quality and PHQ-9 score, the association between self-reported sleep quality and falls disappeared. Depressive symptoms partially mediated the association between self-reported sleep quality and falls based on the significance of indirect effect (β = 0.15, 95% bootstrap CI = 0.08, 0.22). Conclusions: The presence of depressive symptoms might partially mediate the association of self-reported sleep quality with falls among older adults. [ABSTRACT FROM AUTHOR]