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As magnesium oxysulphate cement featured feeble strength and water-resistance, the additive was essential for preparing basic magnesium sulfate cement (BMSC). In this paper, the effects and the mechanism of three organic weak acids on the water-resistance for the flexural strength of BMSC were investigated. The results showed that malic acid failed to ameliorate the water-resistance for the flexural strength, but citric acid and tartaric acid succeeded. The ionization constant and molecular formulas of different weak organic acids would affect the performance, such as the fluidity, strength as well as water-resistance. Therefore, the effect of citric acid was better than tartaric acid, and the optimal dosage of citric acid was 1.0%.

Basic magnesium sulfate cement (BMSC) is a kind of magnesium oxide (MgO)–magnesium sulfate (MgSO4)–water (H2O) modified ternary cementitious material prepared from light burned magnesia, magnesium sulfate heptahydrate, water and additives. The effects of α-magnesium oxide/magnesium sulfate ratio (MO/MS), water/magnesium sulfate ratio (W/MS), sand-to-binder ratio (s/b) and superplasticiser dosage (SPD) on the performance of BMSC mortar were studied for the first time in this work. The results showed that for, optimal 28-day flexural strength, α-MO/MS = 10:1, W/MS = 16:1, s/b = 0.8 and SPD = 0.3%. For optimal 28-day compressive strength, α-MO/MS = 8:1, W/MS = 14:1, s/b = 0.6 and SPD = 0.4%. For best water resistance, α-MO/MS = 12.5:1, W/MS = 14:1, s/b = 0.2 and SPD = 0.1%. Based on these results, the basic mix proportion ranges of BMSC mortar should be α-MO/MS = 8:1–12.5:1, W/MS = 14:1–16:1, s/b = 0.2–0.6 and SPD = 0.1–0.4%.

Lane detection is the most basic part of automatic driving, driver assistance and violation-detection systems. A lane detection method based on semantic discrimination is proposed to address the problems of diversity in illumination, occlusion and lack of prior knowledge about lane markings. Two symmetric ridge operators are designed to improve the precision of candidate-pixel extraction. The double-constrained random sample consensus method (DC-RANSAC) introduces colour and geometric constraints into the lane fitting to reduce the number of iterations and improve the accuracy of the hypothetical model. Classifiers are added to further validate the hypothetical model and identify its underlying semantics. The proposed method was evaluated using two different data sets with various scenarios, including unclear lane markings, dense traffic, occlusion of vehicles, complex shadows, road surface markings, poor lighting conditions, and unknown number of lane markings. The detailed evaluations show that the detection rate of the proposed method is comparable with that of existing state-of-the-art lane detection methods, whereas the precision rate is much higher. Moreover, the experiments prove the reliability of the proposed algorithm in lane marking semantic recognition.

Parathyroid hormone (PTH) and its related peptide (PTH-related peptide 1–34) are two of the Food and Drug Administration-approved bone-promoting drugs for age-related osteoporosis. Treatment with PTH stimulates bone formation. However, the molecular mechanisms of PTH-mediated osteoblast differentiation and cell proliferation are still not completely understood. In this study, we showed that PTH induced endoplasmic reticulum (ER) stress in osteoblasts through the PKR-like endoplasmic reticulum kinase (PERK)-eukaryotic initiation factor 2α (EIF2α)-activating transcription factor 4 (ATF4)-signaling pathway. After separately blocking PERK-EIF2α-ATF4 signaling with two different inhibitors [AMG’44 and integrated stress response inhibitor (ISRIB)] or specific small interfering RNA for PERK and ATF4, the following targets were all downregulated: expression of osteoblast differentiation markers [runt-related transcription factor 2 (Runx2), alkaline phosphatase (Alp), type I collagen (Col1a1), and osteocalcin (Ocn)], cell proliferation markers (CyclinE, CyclinD, and CDC2), amino acid import (Glyt1), and metabolism-related genes (Asns). Additionally, Alp-positive staining cells, Alp activity, matrix mineralization, Ocn secretion, and cell proliferation indexes were inhibited. Interestingly, we found that salubrinal enhanced PTH-induced osteoblast differentiation and proliferation by maintenance of phosphorylation of EIF2α. Furthermore, we observed that PTH increased the association between heat shock protein 90 (HSP90) and PERK and maintained PERK protein stabilization in the early stages of PTH-induced ER stress. Treatment of MC3T3-E1 cells with geldanamycin, an HSP90 inhibitor, decreased PERK protein expression and inhibited osteoblast differentiation and cell proliferation upon PTH treatment. Taken together, our data demonstrate that PTH regulates osteoblast differentiation and cell proliferation, partly by activating the HSP90-dependent PERK-EIF2α-ATF4 signaling pathway.

We propose a stereo matching method based on image fragments. Unlike traditional pixel-based stereos matching methods, we use edge information in the reference image to divide it into small fragments, and we then use the segments to find the best matching fragments in another reference image from the horizontal and vertical directions. We obtain two disparity maps, and using the match confidence value for each disparity map, we can produce a more accurate disparity map. Next, we calculate the exact disparity value for each pixel within the fragment. Finally, the disparity map is filled and smoothed to obtain the final disparity result. Experiments demonstrated that the proposed method has low computation complexity, high matching accuracy, and the disparity of object edge is clear, and it achieved good performance with the Middlebury and KITTI benchmark.

Block matching 3D denoising (BM3D) is an excellent single-image denoising method. However, it still needs to be improved for solving practical problems. In this study, the authors attempt to improve the method of BM3D. First, one of the problems of BM3D is that some of its references cannot perform self-adaption when the noise intensity of the images is changed. Therefore, they propose a method using total variation (TV) to calculate the image noise intensity and make the references perform self-adaption. Second, finding similar blocks in the BM3D method is a time-consuming procedure. To solve this problem, they analyse the relationship between the numbers of similar blocks and denoising effect, improve the process of searching for similar blocks, and reduce the running time. Third, through the experiment they find that the denoising effect of BM3D method in the domain of complex texture is unsatisfactory. Thus, they proposed a hybrid denoising method for the complex texture area, using the new TV model and BM3D method together to restore the image. Their experimental results show that the improved BM3D method performs better than the original BM3D method.

An improved multi-constraint stereo matching strategy is proposed herein. First, the original reference images are downsampled to reduce the matching scale. Absolute difference and rank transform are used as the matching cost. We establish the associated disparity map and the matching cost matrix to constrain the matching process. We use the associated disparity map to apply a smoothing constraint on disparity values. We then apply a uniqueness constraint using the associated disparity map and the matching cost matrix. We also apply a continuity constraint to improve the efficiency of the algorithm. Second, for the downsampled disparity map, the disparity map of the original image is obtained by interpolation and filling. Lastly, the final disparity map is obtained using a sub-pixel refinement strategy. The experimental results demonstrate that the algorithm is obviously superior to the traditional method. In addition, a multi-constraint matching process may be extracted as a framework for combination with other algorithms. Compared with the original algorithms, the fusion algorithm improved matching accuracy by 3% on average.

Osteoblast uses aerobic glycolysis to meet the metabolic needs in differentiation process. Lactate, the end product of glycolysis, presents in the environment with elevated PTH and osteoblast differentiation. Although previous findings showed that lactate promoted osteoblast differentiation, whether lactate affects PTH-mediated osteoblast differentiation is unclear. To investigate this, pre-osteoblast cell line MC3T3-E1 was treated PTH with or without physiological dose of lactate. Lactate increases ALP positive cell formation, increases ALP activity and expression of differentiation related markers, enriches the CREB transcriptional factor target genes in PTH treated cells. Using inhibitors for MCT-1 reveales that lactate effects are MCT-1 independent. Lactate selectively increases Akt and p38 activation but not Erk1/2 and β-Catenin activation. The inhibitors for Akt and p38 inhibit lactate effects on PTH mediated osteoblast differentiation. Using inhibitors for Gαi signaling of GPR81 further increases Alp mRNA levels in lactate and PTH co-treatment cells. However, with the inhibitors for Gβγ-PLC-PKC signaling, the effect of lactate on PTH mediated osteoblast differentiation is inhibited. Our data demonstrate that lactate activates GPR81-Gβγ-PLC-PKC-Akt signaling to regulate osteoblast differentiation that mediated by PTH treatment.

The trade-off between accuracy and computational cost is a central aspect of the problem of real-time vehicle detection, especially for resource-limited platforms. We propose a vehicle-detection method based on template aggregate channel features (TACFs) and soft channel cascade to address the computational requirements of a monocular rearview vehicle detection system. The TACFs is a system of template features designed based on the original aggregate channel features, which is aimed at fully describing the characteristics of the vehicle’s appearance. The proposed soft channel cascade is a pipeline of multiple single-channel classifiers and a full-channel classifier, in which the single-channel classifiers are used to quickly filter the background window and reduce the area of the region of interest, and the full-channel classifier is used to verify the candidate window to improve the detection precision. The proposed method is evaluated on three different datasets with a variety of scenarios involving dense traffic, poor lighting, bad weather conditions, and partial occlusion. Detailed evaluations show that the proposed method enables high-precision detection and high recall rate, and performs better than the existing state-of-the-art vehicle detection methods. In addition, the soft channel cascade can rapidly reject most windows that do not contain any vehicles and enables real-time detection.

No matter how bad the economy worsens, those who with a sought-after skill always are imperative talents gaped after by market. The content manager system (CMS) themes design is becoming one accepted desirable skill in web development. As a guideline for help those who work in computer related fields preparing knowledge and a expertise skill for keeping a position for living or for help the graduates who have just graduated from colleges or universities to get a good pay job. We discuss the technology of one of the most sought-after skills: CMS themes design in this paper. From the required foundation knowledge to the popular CMS themes develop technology all are described. This work is one results of our research in reflection in education of which objective aim to solve the employment difficulties of students.

Reduce the expected number of modifications per pixel (ENMPP) of cover image is a useful way to improve the imperceptibility in steganography. Many works related with this issue have been proposed in recent years. In this paper, a scheme of LSB steganography is proposed which based on concept of finding optimization pixels selection from cover image. The experimental results show that effect of reducing ENMPP is remarkable.

In recent years, more and more students those have just graduated from colleges and universities are hard to find a job for their expertise skills are inadequacy for the potential positions demand. As a guideline for these students of computer related majors preparing knowledge and expertise skills for getting a good position in web development, we discuss the education of the most sought-after skill, framework knowledge in this paper. From the required foundation knowledge to the latest new concepts related framework all are described. This work is one results of our research in reflection in education of which objective aim to solve the employment difficulties of students.

Currently, the education reform is a widespread concerning issue in China. As the education model has been unchanged for dozens of years, some disadvantage that improper to the present era had become gradually apparent. For keep abreast of new technology, the computer science as one of the fastest developing disciplines and itself also impacts on modern education deeply needs education reform timely more than others. In this paper, we analysis the issues exist in computer education based on a case study research, and the countermeasures contributing to these issues also are presented.