Understanding the role of metakaolin towards mitigating the shrinkage behavior of alkali-activated slag

This research investigates the mechanism of metakaolin for mitigating the autogenous and drying shrinkages of alkali-activated slag with regard to the activator parameters, including concentration and modulus. The results indicate that the incorporation of metakaolin can decrease the initial viscosity and setting time. Increasing activator concentration can promote the reaction process and shorten the setting time. An increase in the metakaolin content induces a decrease in compressive strength due to reduced formation of reaction products. However, increasing activator dosage and modulus can improve the compressive strength of alkali-activated slag containing 30% metakaolin. The inclusion of metakaolin can mitigate the autogenous and drying shrinkage of alkali-activated slag by coarsening the pore structure. On the other hand, increases in activator concentration and modulus result in an increase in magnitude of the autogenous and drying shrinkage of alkali-activated slag containing metakaolin. The influence of the activator modulus on the shrinkage behavior of alkali-activated slag-metakaolin binary system should be further investigated

Identification of candidate genes and clarification of the maintenance of the green pericarp of weedy rice grains

The weedy rice (Oryza sativa f. spontanea) pericarp has diverse colors (e.g., purple, red, light-red, and white). However, research on pericarp colors has focused on red and purple, but not green. Unlike many other common weedy rice resources, LM8 has a green pericarp at maturity. In this study, the coloration of the LM8 pericarp was evaluated at the cellular and genetic levels. First, an examination of their ultrastructure indicated that LM8 chloroplasts were normal regarding plastid development and they contained many plastoglobules from the early immature stage to maturity. Analyses of transcriptome profiles and differentially expressed genes revealed that most chlorophyll (Chl) degradation-related genes in LM8 were expressed at lower levels than Chl a/b cycle-related genes in mature pericarps, suggesting that the green LM8 pericarp was associated with inhibited Chl degradation in intact chloroplasts. Second, the F2 generation derived from a cross between LM8 (green pericarp) and SLG (white pericarp) had a pericarp color segregation ratio of 9:3:4 (green:brown:white). The bulked segregant analysis of the F2 populations resulted in the identification of 12 known genes in the chromosome 3 and 4 hotspot regions as candidate genes related to Chl metabolism in the rice pericarp. The RNA-seq and sqRT-PCR assays indicated that the expression of the Chl a/b cycle-related structural gene DVR (encoding divinyl reductase) was sharply up-regulated. Moreover, genes encoding magnesium-chelatase subunit D and the light-harvesting Chl a/b-binding protein were transcriptionally active in the fully ripened dry pericarp. Regarding the ethylene signal transduction pathway, the CTR (encoding an ethylene-responsive protein kinase) and ERF (encoding an ethylene-responsive factor) genes expression profiles were determined. The findings of this study highlight the regulatory roles of Chl biosynthesis- and degradation-related genes influencing Chl accumulation during the maturation of the LM8 pericarp

Improving Energy Efficiency of Location Sensing on Smartphones

Location-based applications have become increasingly popular on smartphones over the past years. The active use of these applications can however cause device battery drain owing to their powerintensive location-sensing operations. This paper presents an adaptive location-sensing framework that significantly improves the energy efficiency of smartphones running location-based applications. The underlying design principles of the proposed framework involve substitution, suppression, piggybacking, and adaptation of applications ’ location-sensing requests to conserve energy. We implement these design principles on Android-based smartphones as a middleware. Our evaluation results show that the design principles reduce the usage of the power-intensive GPS (Global Positioning System) by up to 98 % and improve battery life by up to 75%

Network Pharmacology and Molecular Docking Analysis on Molecular Targets and Mechanisms of Buyang Huanwu Decoction in the Treatment of Ischemic Stroke

Background and Objective. With the exact clinical efficacy, Buyang Huanwu decoction (BHD) is a classical prescription for the treatment of ischemic stroke (IS). Here, we aimed to investigate the pharmacological mechanisms of BHD in treating IS using systems biology approaches. Methods. The bioactive components and potential targets of BHD were screened by TCMSP, BATMAN-TCM, ETCM, and SymMap databases. Besides, compounds that failed to find the targets from the above databases were predicted through STITCH, SwissTargetPrediction, and SEA. Moreover, six databases were searched to mine targets of IS. The intersection targets were obtained and analyzed by GO and KEGG enrichment. Furthermore, BHD-IS PPI network, compound-target network, and herb-target-pathway network were constructed by Cytoscape 3.6.0. Finally, AutoDock was used for molecular docking verification. Results. A total of 235 putative targets were obtained from 59 active compounds in BHD. Among them, 62 targets were related to IS. PPI network showed that the top ten key targets were IL6, TNF, VEGFA, AKT1, etc. The enrichment analysis demonstrated candidate BHD targets were more frequently involved in TNF, PI3K-Akt, and NF-kappa B signaling pathway. Network topology analysis showed that Radix Astragali was the main herb in BHD, and the key components were quercetin, beta-sitosterol, kaempferol, stigmasterol, etc. The results of molecular docking showed the active components in BHD had a good binding ability with the key targets. Conclusions. Our study demonstrated that BHD exerted the effect of treating IS by regulating multitargets and multichannels with multicomponents through the method of network pharmacology and molecular docking

The attitude adjustment algorithm in drilling end-effector for aviation

To ensure the perpendicularity of drilling holes in aircraft manufacturing, the attitude of spindle axis must be adjusted to coincide with the normal vector of drilling point before drilling. The double eccentric discs-spherical pair structure was used as attitude adjustment mechanism in drilling end-effector. Therefore, the attitude adjustment algorithm of spindle axis is proposed in this article. There were two attitudes for current and target position, respectively, and the rotation sequence of each eccentric disc would affect the attitude adjustment efficiency. This article presents the path planning and optimal solution choosing from multiple solutions. Finally, the effectiveness and accuracy of the algorithm are verified in simulation and drilling experiment, resulting in a normality tolerance of ±0.5° and precision of H9

Octominin: An antimicrobial peptide with antibacterial and anti-inflammatory activity against carbapenem-resistant Escherichia coli both in vitro and in vivo

ABSTRACT: Objectives: The emergence of carbapenem-resistant Escherichia coli (CREC) is a global concern as its prevalence restricts treatment options and poses a considerable threat to public health. In this study, in vitro and in vivo activity of the antimicrobial peptide Octominin against CREC was investigated to reveal possible mechanisms of action. Furthermore, its safety and factors influencing its antibacterial effect were assessed. Additionally, the anti-inflammatory effects of Octominin were examined. Methods: The antimicrobial activity of Octominin against 11 strains of CREC was determined using the broth microdilution method, growth curve, and time-kill assay. Its possible mechanism of action was unraveled using the propidium iodide and N-phenyl-1-naphthylamine fluorochrome and lipopolysaccharide-binding assays. To understand the safety and stability of Octominin, its cytotoxicity, hemolysis, and antibacterial activity under various conditions (i.e, temperature, ions) were estimated. Additionally, a Galleria mellonella infection model was utilized to evaluate the efficacy of Octominin in vivo, and qRT-PCR was performed to assess its effect on the expression of proinflammatory cytokines. Results: Octominin displayed a significant antibacterial effect, with MICs of 4–8 µg/mL and MBCs of 8–16 µg/mL. Octominin exerted its antibacterial effect by disrupting bacterial membranes. Cytotoxicity and hemolysis tests demonstrated the potential application of Octominin in vivo. The G. mellonella infection model asserted the in vivo efficacy of Octominin. Furthermore, Octominin inhibited the expression of proinflammatory cytokines. Although the temperature had little effect on its the activity, serum and ions reduced activity. Conclusion: Octominin is a promising alternative agent with remarkable antibacterial and anti-inflammatory effects for treating infections caused by CREC

Confrontation as a Mediator between Sense of Coherence and Self-management Behaviors among Elderly Patients with Coronary Heart Disease in North China

Summary: Purpose: Self-management is critical to improve health outcomes of elderly patients with coronary heart disease (CHD). Sense of coherence (SOC) is found to be linked with self-management behaviors. However, their deeper relationship is not clear. The purposes of this study were to investigate the association between SOC and self-management behaviors among elderly CHD patients in China, and whether confrontation mediates this association. Methods: A cross-sectional design was used. A total of 275 elderly patients with CHD recruited from the cardiology department in a general hospital in North China were surveyed from October 2015 to April 2016. SOC, confrontation, and self-management behaviors were measured using the Chinese version of the SOC scale, subscale of Medical Coping Modes Questionnaire—Confrontation, and the CHD self-management scale, respectively. Correlation analysis and path analysis were conducted to analyze the data. Results: The mean (±standard deviation) scores of SOC, confrontation, and self-management behaviors were 62.20 (±9.61), 19.55 (±3.15), and 76.17 (±10.63), respectively. Correlation analysis showed that SOC, confrontation, and self-management behaviors were significantly correlated with each other. Path analysis indicated that SOC exerted a direct effect on self-management behaviors, whereas could affect self-management indirectly via confrontation. Bootstrap test result showed that confrontation played a mediating role (β = .20, p < .001) in the relationship between SOC and self-management behaviors. Conclusion: SOC was related to self-management behaviors, whereas confrontation mediated the effect of SOC on self-management behaviors. In practice, the role of confrontation coping should be valued when developing strategies to strengthen SOC and to improve self-management practice among elderly CHD patients. Keywords: aged, coping, coronary heart disease, self-care, sense of coherenc

Self-assembled drug delivery system based on low-molecular-weight bis-amide organogelator: synthesis, properties and <i>in vivo</i> evaluation

<p><i>Context</i>: Orgnaogels based on amino acid derivatives have been widely used in the area of drug delivery.</p> <p><i>Objective</i>: An organogel system based on l-lysine derivatives was designed and prepared to induce a thermal sensitive implant with higher transition temperature, better mechanical strength, and shorter gelation time.</p> <p><i>Materials and methods</i>: The organogel was prepared by injectable soybean oil and methyl (<i>S</i>)-2,5-ditetradecanamidopentanoate (MDP), which was synthesized for the first time. Candesartan cilexetil (CC) was chosen as model drug. Different formulations were designed and optimized by response surface method. Thermal, rheology properties, and gelation kinetics of the optimized formulation had been characterized. The release behaviors <i>in vitro</i>, as well as <i>in vivo</i> were evaluated in comparison with the oily solution of drugs. Finally, the local inflammation response of <i>in situ</i> organogel was assessed by histological analysis.</p> <p><i>Results and discussion</i>: Results showed that the synthesized gelator, MDP, had a good gelation ability and the organogels obtained via the self-assembly of gelators in vegetable oils exhibited great thermal and rheology properties, which guaranteed their state in body. <i>In vivo</i> pharmacokinetic demonstrated that the organogel formulation could extend the drug release and maintain a therapeutically effective plasma concentration at least 10 d. In addition, this implant showed acceptable moderate inflammation.</p> <p><i>Conclusion</i>: The <i>in situ</i> forming l-lysine-derivative-based organogel could be a promising matrix for sustained drug delivery of the drugs with low solubility.</p