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This paper proposes a driving road slope measurement algorithm to provide a reference for adjusting the vertical angle of headlights. It uses a combination of Canny Edge Detection and Hough Transform to process images from camera to detect and fitting lanes. The angle of ramp can be calculated by Mathematical Model.

In metro engineering, due to the large amount of lining concrete pouring, it is easy to produce large shrinkage deformation in the maintenance stage, which leads to cracks in lining concrete and seriously affects the operation and safety of metro. Therefore, this paper adopts the test scheme of large dosage of mineral admixtures to compare and analyze the influence of the amount of cementing material, the dosage of mineral admixtures and the binder/water ratio on the dry shrinkage performance of metro lining concrete. The results show that the shrinkage ratio of lining concrete increases with the increase of cementitious material content or binder/water ratio, but decreases with the increase of the dosage of mineral admixtures. When the cement variety is P.I 42.5 and the dosage of mineral admixture is 40%, or the cement variety is P.I 52.5 and the dosage of mineral admixture is 50%, the shrinkage deformation of lining concrete is small, which can meet the needs of subway construction and will have a broad application prospect in practical engineering.

The effective mineral admixture in mortar can consume the calcium hydroxide produced by hydration reaction because of pozzolanic effect. For high volume mineral admixture mortar, when the replacement ratio exceeds a certain ‘threshold’ value, the supply of Ca(OH)2 amount is insufficient, the superfluous and ineffective mineral admixture will no longer react in mortar but as fine aggregate. This study presents an experiment study on the threshold value of effective replacement ratio of fly ash mortar by the comprehensive analysis of Ca(OH)2 amount and consumption curves. Under the conditions of different curing temperature, the effective replacement ratios of fly ash mortar have been determined ultimately. The results showed that Ca(OH)2 amount and consumption in mortar both decreased with replacement ratio. For fly ash mortar, at 20°C curing temperature, when the replacement ratio was less than 40%, the Ca(OH)2 amount decreased obviously with replacement ratio. However, when replacement ratio was more than 40%, Ca(OH)2 amount at 91d changed slightly with replacement ratio, the Ca(OH)2 amount was consumed to a limit value at this time. Under the condition of 30°C curing temperature, when the replacement ratio exceeded 30%, the change of Ca(OH)2 amount with replacement ratio was close to a straight line, the superfluous fly ash no longer consumed Ca(OH)2 basically. Moreover, the consumption of Ca(OH)2 was not much difference to the Ca(OH)2 amount at the same replacement ratio under the condition of 20°C curing temperature. This result has a great significance on effective utilization of mineral admixtures in engineering application.

Recycled aggregate can be used as a substitute for natural aggregate to produce good regenerated concrete, so the text use recycled coarse aggregate and recycled fine aggregate to substitute for natural aggregate with different replacement rates preparing double recycled aggregate concrete, and researching the effect of the quality and replacement rate of recycled aggregate on the mechanical properties of recycled aggregate systematically. The results show that the compressive strength of double recycled aggregate concrete is increased gradually with the improvement of the quality of recycled aggregate, and the effect from weak to strong is class I, class II and class III. On the other hand, the compressive strength of double recycled aggregate concrete is decreased gradually with the increase of the replacement rate of recycled aggregate, and the maximum reduction is up to 57.2%. Therefore, the simultaneous use of recycled coarse aggregate and recycled fine aggregate have an effect of “double weakening” on the compressive strength of recycled concrete, and it can be applied to the concrete products of low strength grade.

Gamma-aminobutyric acid (GABA), a nonproteinous amino acid with some benefits on human health, is synthesized by GABA-shunt and the polyamine degradation pathway in plants. The regulation of Ca2+ and aminoguanidine on GABA accumulation in germinating soybean (Glycine max L.) under hypoxia-NaCl stress was investigated in this study. Exogenous Ca2+ increased GABA content significantly by enhancing glutamate decarboxylase gene expression and its activity. Addition of ethylene glycol tetra-acetic acid into the culture solution reduced GABA content greatly due to the inhibition of glutamate decarboxylase activity. Aminoguanidine reduced over 85% of diamine oxidase activity, and 33.28% and 36.35% of GABA content in cotyledon and embryo, respectively. Under hypoxia–NaCl stress, the polyamine degradation pathway contributed 31.61–39.43% of the GABA formation in germinating soybean.

In the production of L-lactic acid, the residual sugar in fermentation broth would lead to increased sugar content in its commercial products, bringing about lactic acid deterioration because of Maillard reactions and thus shortening their shelf life. In this work, the residual sugar components in L-lactic acid industrial fermentation broth with agricultural biomass-derived sugar were determined by means of high-performance anion-exchange chromatography (HPAEC) coupled with pulsed amperometric detection (PAD). A feasible off-line sample clean-up procedure consisting of sodium oxalate extraction, ethanol extraction and ion-exchange column extraction was developed to remove calcium ions, proteins, anion acids and organic acids before analysis, and their removal efficiencies were 100, 98.74, 97.99 and 99.41%, respectively. Under the optimized analytical conditions, the seventeen sugars, including four monosaccharides, eight disaccharides and five oligosaccharides, have been completely separated in one experimental run on a Dionex Carbopac PA 200 column with sodium hydroxide and sodium acetate as eluents. The method was validated, with good linearity (R2 > 0.99), high precision (RSDs 86.95% for short chain carbohydrates (degree of polymerization, DP < 4), while recoveries ranged from 81.87 to 61.41% for DP4 to DP7. The method was successfully applied for analysis of the residual sugar in lactic acid broth with a salt content as high as 120 g L−1 calcium lactate, using different kinds of starch (corn starch, corn flour and cassava starch) hydrolysates as carbon sources. Isomaltose (47.97–60.43%), sucrose (17.50–29.73%) and trehalose (3.05–7.51%) were the main components of residual sugar in these broths.

Alpha-lipoic acid (ALA), a naturally occurring compound, exerts powerful protective effects in numerous cardiovascular disease models. However, the pharmacological property of ALA on cardiac hypertrophy has not been well investigated. The present study was carried out to determine whether ALA exerts a direct anti-hypertrophic effect in cultured cardiomyocytes and whether it modifies the hypertrophic process in vivo. Furthermore, we determined the potential underlying mechanisms for these actions. Treatment of cardiomyocytes with phenylephrine (PE) for 24 h produced a marked hypertrophic effect as evidenced by significantly increased in ANF and BNP mRNA levels, as well as cell surface area. These effects were attenuated by ALA in a concentration-dependent manner with a complete inhibition of hypertrophy at a concentration of 100 µg/mL. PE-induced cardiomyocyte hypertrophy was associated with increased mRNA and protein levels of C/EBPβ, which were inhibited by pretreatment with ALA. However, when cardiomyocytes were co-transfected with C/EBPβ, ALA failed to inhibit hypertrophic responses. Upregulation of C/EBPβ expression was also evident in rats subjected to 4 weeks of coronary artery ligation (CAL). However, rats treated with ALA demonstrated markedly reduced hemodynamic and hypertrophic responses, which were accompanied by attenuation of upregulation of C/EBPβ. Taken together, our results revealed a robust anti-hypertrophic and anti-remodeling effect of ALA, which is mediated by inhibition of C/EBPβ activation.

A rapid quantitative evaluation method for Siraitia grosvenorii cells was successfully developed based on plant cells' capacitance value detected by a viable cell mass monitor and the cryopreservation of S. grosvenorii suspension cells was optimized. The survival rate of S. grosvenorii cells was quantitatively measured by viable cell mass monitor and 2, 3, 5-triphenyltetrazolium chloride (TTC). An optimum cryoprotectant recipe is that the growth medium contained 10% sucrose and 10% DMSO. The experimental results also showed higher cell survival rates and cell viabilities were achieved when suspension cells were treated with pretreatment of 0.2 mol/L sucrose. With the increase of concentration of sucrose, however, the cell survival rate was decreased. And the cell survival rate represented a bell shape with the increase of pretreatment time. The highest cell survival rate and cell viability were obtained with the 9 h' s pretreatment. In addition, there was a good correlation between the cell survival rate measured by cell recovery test and that measured by viable cell mass monitor, while there were no significant differences in the cell morphology and the ability of mogrosides V production by S. grosvenorii cells cultured in suspension after cryopreservation. Therefore, the evaluation method developed based on the viable cell mass monitor has good feasibility and reliability.建立了一种基于活细胞电容值定量测定的植物细胞超低温保藏的快速评价方法，优化了罗汉果细胞超低温保藏方法。通过采用活细胞传感仪测定冻存后细胞的存活率并结合细胞生活力(细胞线粒体活性/TTC)对罗汉果细胞的低温保藏过程进行优化，确定了罗汉果细胞较为适宜的冷冻保护剂组分为基本培养基中添加10%的蔗糖和10%的DMSO。预处理剂的考察实验表明，采用0.2 mol/L 蔗糖的预处理剂处理细胞时冻存后细胞存活率和细胞活力较高；采用0.2 mol/L蔗糖预处理剂处理细胞时，随着预处理时间的增加，细胞存活率先增加后降低，预处理时间为9 h时，细胞存活率和细胞活力最高。保藏后的细胞复苏实验结果表明：细胞存活率与采用活细胞电容值得到的细胞存活率具有很好的一致性，同时经过冻存的细胞复苏培养后，仍保留了原始细胞的形态和合成甜苷V的特性，说明该冻存方法适用于罗汉果细胞的超低温保藏。因此基于活细胞传感仪测得的电容值进行细胞冻存过程细胞活性的快速评价方法具有较好的可行性和可靠性。.

In order to ensure the construction performance of recycled concrete, and the influence of recycled coarse aggregate on water consumption of recycled concrete was studied, and used three kinds of recycled coarse aggregate with different quality to prepare recycled concrete with different replacement rate. Study the influence of recycled coarse aggregate quality and replacement rate on the absolute water consumption of recycled coarse aggregate concrete systemically. The experiment is based on the absolute water consumption of ordinary concrete, puts forward the formula for predicting the absolute water consumption of recycled coarse aggregate concrete based on aggregate quality and replacement rate for the first time. And based on the test date, the error of the prediction formula is compared. The results show that there is a good linear relationship between the absolute water consumption and the replacement rate of recycled coarse aggregate concrete. With the improvement of the quality of recycled coarse aggregate, the absolute water consumption is significantly reduced. According to the experimental data, the maximum calculation error of recycled aggregate concrete is -1.97%, which has high accuracy and good applicability.

We integrated orthogonal experiment technique with three factors and three levels, and employed single-surface capillary absorption method to study the effects of water-cement ratio (W/C), the loading of carbon nanotube (wCNT), the addition of silane waterproofing agent (wKH55) on the waterproof performances of CNT cement-based materials modified by doped silane waterproofing agent (KH/CNT/CC). Orthogonal range analysis reveals, when the KH/CNT/CC specimen is in condition of W/C=0.32, wCNT=0.2%, wKH55=0.5%, the mass of water absorption is the minimum, and the water resistance is the best. The absorbed water mass after 96h of KH/CNT/CC with wKH55=0.5% is decreased by 170.1g/m2 when compared with the case with wKH55=0.1%, the incorporation of silane waterproofing agent has effectively improve the impermeability of CNT cement-based composites. This will provide a reference for the development of the intrinsic sensors with excellent waterproof performance.

Most of the fermentation experiment designs were limited by the low-throughput of shake flask, especially for the medium optimization. A simple high-throughput screening system was developed for the determination of pigment in Monascus purpureus fermentation samples. This downscaled system was designed to optimize medium composition combined with statistical methods. The total 29 experiments designed by the Box-Behnken were used to study the 4 most important operating variables on pigment production. The analysis revealed that the optimum concentrations of glucose, peptone, NaNO3, and KH2PO4 were 51.42, 4.91, 1.00, and 1.00 g/L, respectively. A production of 69.5 U/mL was achieved in agreement with the prediction (68.9 U/mL) fermented in 24-deep-well microtiterplates. Furthermore, the fermentation medium optimized in the high-throughput system was verified in shake flasks, and the pigment production could be enhanced from 206.5 U/mL in un-optimized medium to 265.8 U/mL, giving nearly 1.30-fold increase in production.

High levels of γ-aminobutyric acid (GABA) accumulate in plant tissues under various stresses and exogenous additives. The purpose of this research is to provide an effective finding that can prove a rapid accumulation of GABA in germinated soybean (Glycine max L.) in response to different additives under hypoxia. Hypoxia-induced GABA accumulation in soybean embryo resulted in part from polyamine oxidation. Response to different concentration of glutamate (Glu), pyridoxal phosphate, arginine, CuCl2, NaCl, and CaCl2, a significant difference including GABA accumulation, changes of Glutamate decarboxylase (GAD), and Diamine oxidase activity (DAO) activity in germinated soybean under hypoxia occurred (p

Effects of soaking temperature, soaking time, opportunity of aeration treatment, culture temperature, pH value, and air flow rate on γ-aminobutyric acid (GABA) accumulation during germination of soybean (Glycine max (L.) Merr.) were investigated in this study. The objective of this study was to optimize the culture conditions of GABA production in germinated soybeans. Results showed that soaking at 30 °C for 4 h was found to be the most effective soaking ways that made soybean seeds have sufficient moisture, satisfactory germination, and GABA accumulation. The suitable stress opportunity was dark culture for 2 days with distilled water and then hypoxia stress in aerated culture medium for 2 days in a dark incubator at 30 °C. Under these conditions, the maximum GABA content (2.24 mg/g DW) was 3.5 times higher than the initial sample of aeration treatment (0 h) and 12.5 times higher than the raw material. Correlation analysis also revealed that GABA accumulation was significantly correlated to the corresponding physiochemical indexes (p < 0.01). Box-Behnken experimental analysis showed that the optimal condition with aeration treatment for GABA accumulation in germinated soybean was at a temperature of 30.5 °C, a pH value of 4.1, and an air flow rate of 0.9 L/min; the predicted highest GABA yield was 2.60 mg/g DW, which was 15.2 times higher than raw seeds. Analysis of variance and confirmatory trials for the regression model suggested that the model can quite exactly predict GABA accumulation in soybean during germination.

Reduced glutathione (GSH) from fermentation broth of Saccharomyces cerevisiae was extracted with ethanol without disruption of the cells. The effects of ethanol concentration, extraction temperature and extraction time were assessed by using 2(3) full factorial designs (FFD). Preliminary studies showed that ethanol concentration had the most influence on GSH yield by ethanol extraction, based on the first order regression coefficients derived using MINITAB software, and an optimal ethanol concentration (25%, v/v) was obtained. However, compared to the conventional extraction technique (hot water extraction), there was no significant advantage in yield of GSH from yeast cells using ethanol extraction under these optimized conditions. But ethanol extraction has several advantages, such as lower energy consumption and lower protein concentration of extraction broth, which may reduce the complexity and cost of the purification process. Hence, ethanol extraction which does not disrupt yeast cells could be an inexpensive, simple and efficient alternative to conventional extraction techniques in the GSH industry.

An on-line monitoring of viable-cell mass in high-cell-density fed-batch cultivations of Saccharomyces cerevisiae grown on an industrial complex medium was performed with an in situ capacitance probe fitted to a 50-l fermentor. Conventional off-line biomass determinations of several parameters, including dry cell weight (DCW), optical density at 600 nm wavelength (OD(600)), packed mycelial volume (PMV) and number of colony forming units (CFU), were performed throughout the bioprocess and then compared with on-line viable-cell concentrations measured using a capacitance probe. Capacitance versus viable biomass and all off-line biomass assay values were compared during glutathione fermentation in industrial complex culture media. As a result, the relationship between the number of colony forming units and capacitance with a correlation coefficient (R) of 0.995 was achieved. Simultaneously, compared with those determined by at-line indirect estimation methods including oxygen uptake rate (OUR) and carbon dioxide evolution rate (CER), the specific growth rates estimated by on-line capacitance measurement could be more reliable during glutathione fermentation. Therefore, it is concluded that a capacitance probe is a practical tool for real-time viable biomass monitoring in high-cell-density fed-batch cultivation in a complex medium.

The objective of the study is to investigate the effects of chronic aluminum overload on rat liver function and its induction of pathological changes in metal ion levels and oxidative stress in hepatic tissues. Wistar rats were intragastrically administered aluminum gluconate (200 mg Al(3+)/Kg) once a day, 5 days a week, for 20 weeks. HE staining was used to visualize pathological changes in rat liver tissue. A biochemical method was adopted to detect ALT, AST, ALP, and GGT levels, as well as liver SOD activity and blood plasma MDA content. A plasma atomic emission spectrophotometer was used to detect Al, Mn, Fe, Zn, and Cu ion contents in liver tissue. Our results showed obvious vacuolar degeneration, granular degeneration, and spotty necrosis in chronic Al-overload rat hepatocytes. The levels of ALT, AST, ALP, and GGT were significantly increased. Liver SOD activity was significantly decreased, and MDA content was significantly increased. In Al-overload rat liver, Al, Mn, Fe, and Cu contents were significantly increased, and in Al-overload rat serum, Mn, Fe, Zn, and Cu contents were significantly decreased. However, the Al level in Al-overload rat serum was not significantly different from that in control rat serum. These results suggest that chronic aluminum overload causes obvious damage to rat liver and causes imbalances in Al, Mn, Fe, Zn, and Cu levels in rat liver and serum. Metal ion imbalance-related oxidative stress may be involved in the mechanism of chronic liver injury caused by aluminum overload.

Although COX-2 inhibition in animal models of neurodegenerative diseases has shown neuroprotection, recent studies have revealed some serious side effects (ulcers, bleeding, fatal cerebrovascular diseases etc.) and the limited benefits of COX-2 inhibitors. A more focused approach is necessary to explore the therapeutic effect of the COX downstream signaling pathway in neurological research. The aim of this study was to explore the alterations of the PGES-PGE 2 -EP signal pathway and the effect of misoprostol on neurodegeneration by chronic aluminum-overload in rats. Adult rats were treated by intragastric administration of aluminum gluconate. The PGE 2 content and expression of PGES and EPs in the hippocampi of rats were detected using ELISA, q-PCR and Western blot analysis, respectively. The content of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in the rat hippocampi were also detected. The misoprostol treatment dose-dependently improved spatial learning and memory function as well as healing after hippocampal neuron damage induced by chronic aluminum-overload in rats. Meanwhile, the administration of misoprostol resulted in a decrease in the PGE2 level and down-regulation of the mPGES-1, EP 2 and EP 4 expression levels, while there was a dosedependent up-regulation of EP3 expression. These results suggest that misoprostol possesses a neuroprotective property, and the mechanism involves affecting the EP3 level and reducing the endogenous production of PGE 2 through a negative feedback mechanism, increasing the EP 3 expression level, decreasing the EP 2 and EP 4 expression levels, and rebuilding the mPGES-1-PGE 2 -EP 1-4 signal pathway balance. In this way, misoprostol has a counteractive effect on oxidant stress and inflammation in the central nervous system. The PGES-PGE2-EPs signaling pathway is a potential therapeutic strategy for treating neurodegeneration in patients.

Background Acute and chronic brain damages including neurodegenerative diseases are a group of neuroinflammation-associated diseases characterized by cognitive function defect and progressive neuron loss. The pathophysiological procession of brain damages involves the overexpression of cyclooxygenase (COX)-2. Owing to the limited benefit to chronic brain damage and the late adverse effect of COX-2 inhibitors, the COX downstream signaling pathway has become a focus in neurological research. In order to explore the mechanism of aluminum neurotoxicity and the importance of COX2 downstream signaling pathways to chronic brain damage, the present study was designed to simultaneously observe the prostaglandin (PG) contents, and the expressions of PG synthases and PG receptors of hippocampus in a rat model induced by chronic administration of aluminium gluconate. Methods A rat model of chronic brain damage was established by chronic intragastric administration of aluminium gluconate (Al3+ 200 mg/kg per day, 5d a week for 20 weeks). PG contents, the expressions of PG synthases, and the expressions of PG receptors in rats were measured by ELISA, RT-PCR and Western blotting, respectively. Results Chronic aluminium gluconate administration resulted in hippocampal neuron injury and learning and memory disorders in rats. Aluminium gluconate administration also resulted in increased levels of PGE2, PGD2, TXA2, PGI2, and PGF2α in rat hippocampus. The DP1, EP2, IP, mPGES-1, EP4, PGIS and TXAS mRNA expressions, and the DP1, EP2 and IP protein expressions significantly increased in the Al-treated hippocampus, while the EP3 and FP mRNA and protein expressions and the TP mRNA expression decreased. Conclusions The PGS/PGs/PG receptors signaling pathway in chronic aluminium gluconate-overloaded rat hippocampus is disturbed, which may be involved in the mechanism of aluminium neurotoxicity.

Gamma-aminobutyric acid (GABA), a nonproteinous amino acid with some benefits on human health, is synthesized by GABA-shunt and the polyamine degradation pathway in plants. The regulation of Ca

Improvement of microbial strains for the high-production of industrial products has been the hallmark of all commercial fermentation processes. Strain improvement has been conventionally achieved through mutation and selection. However, most of the screenings were performed in shake flasks, which made the screening procedure very complex, time-consuming, and inefficient. Most mutant spore suspension had no chance to be screened due to the low-throughput of shake flasks and had to be sacrificed. In this paper, in order to get a Cephalosporin C (CPC) high-yield stain, traditional mutagenesis was employed to obtain the mutant library and gave them the equal screening chance by a novel mixture culture method combined with high-throughput screening method. The good correlation of fermentation results between differing-scale cultivations confirmed the feasibility of utilizing the 48-deep microtiter plates as a scale-down tool instead of shake flasks for culturing high-aerobic microbes with long cultivation period. The microbioassay based on the antibacterial activity of CPC against Alcaligenes faecalis was used to select mutants. As a result, the high-yield strain W-6 was successfully screened out and the CPC titer was nearly 50 % higher than that of the parental strain in the shake flask. The CPC production of strain W-6 was further validated in 50 l bioreactor, and the CPC production reached 32.0 g/l, twofold higher than that of the wild strain.

Background Aluminum overload can cause severe brain injury and neurodegeneration. Previous studies suggest that prostacyclin synthase (PGIS) expression and prostacyclin receptor (IP) activation are beneficial for treatment of acute traumatic and ischemic brain injury. However, the potential value of PGIS/IP signaling pathway to chronic brain injury is still unclear. In this study, we investigated the change of PGIS/IP signaling pathway and the effect of beraprost sodium (BPS) on chronic brain injury in chronic aluminum-overload rats. Methods Rat model of chronic cerebral injury was established by chronic intragastric administration of aluminum gluconate(Al3+ 200 mg/kg per day,5d a week for 20 weeks). The methods of ELISA, qRT-PCR and Western blotting were used to detect the PGI2 level and the PGIS and IP mRNA and protein levels in hippocampi of chronic aluminum-overload rats, respectively. Rat hippocampal superoxide dismutase (SOD) activity and malondialdehyde (MDA) content also were measured. The effects of BPS (6, 12 and 24 μg⋅kg-1) on brain injury in chronic aluminum-overload rats were evaluated. Results Compared with the control group, PGIS mRNA expression, PGI2 level, and the IP mRNA and protein expressions significantly increased in hippocampi of chronic aluminum-overload rats. Administration of BPS significantly improved spatial learning and memory function impairment and hippocampal neuron injury induced by chronic aluminum overload in rats. Meanwhile, administration of BPS resulted in a decrease of PGI2 level and downregulation of PGIS and IP expressions in a dose-dependent manner. Aluminum overload also caused a decrease of SOD activity and an increase of MDA content. Administration of BPS significantly blunted the decrease of SOD activity and the increase of MDA content induced by aluminum overload in rats. Conclusions BPS has a significant neuroprotective effect on chronic brain injury induced by aluminum overload in rats. Remodeling the balance of PGIS/IP signaling pathway and inhibition of oxidative stress involve in the neuroprotective mechanism of BPS in aluminum-overload rats. The PGIS/IP signaling pathway is a potential therapeutic strategy for chronic brain injury patients.