Absolute stability of lurie systems with impulsive effects

AbstractThis paper studies absolute stability of Lurie systems with impulsive effects. Using the method of Lyapunov functions and the variation of parameters technique, we establish sufficient conditions for absolute stability

Chinese medicine, Qijudihuang pill, mediates cholesterol metabolism and regulates gut microbiota in high-fat diet-fed mice, implications for age related macular degeneration

Background: Traditional Chinese Medicines have been used for thousands of years but without any sound empirical basis. One such preparation is the Qijudihuang pill (QP), a mixture of eight herbs, that has been used in China for the treatment of various conditions including age-related macular degeneration (AMD), the most common cause of blindness in the aged population. In order to explain the mechanism behind the effect of QP, we used an AMD model of high-fat diet (HFD) fed mice to investigate cholesterol homeostasis, oxidative stress, inflammation and gut microbiota.Methods: Mice were randomly divided into three groups, one group was fed withcontrol diet (CD), the other two groups were fed with high-fat-diet (HFD). OneHFD group was treated with QP, both CD and the other HFD groups were treatedwith vehicles. Tissue samples were collected after the treatment. Cholesterollevels in retina, retinal pigment epithelium (RPE), liver and serum weredetermined using a commercial kit. The expression of enzymes involved incholesterol metabolism, inflammation and oxidative stress was measured withqRT-PCR. Gut microbiota was analyzed using 16S rRNA sequencing.Results: In the majority of the lipid determinations, analytes were elevated by HFD but thiswas reversed by QP. Cholesterol metabolism including the enzymes of bile acid (BA) formationwas suppressed by HFD but again thiswas reversed by QP. BAs play amajor role in signaling between host andmicrobiome and this is disrupted by HFD resulting in major changes in the composition of colonic bacterial communities. Associated with these changes are predictions of the metabolic pathway complexity and abundance of individual pathways. These concerned substrate breakdowns, energy production and the biosynthesis of proinflammatory factors but were changed back to control characteristics by QP.Conclusion: We propose that the ability of QP to reverse these HFD-inducedeffects is related to mechanisms acting to lower cholesterol level, oxidative stress and inflammation, and to modulate gut microbiota

Effect of Ultrasonic Surface Rolling Process on Surface Properties and Microstructure of 6061 Aluminum Alloy

Nano-surface layers were prepared on the surface of 6061 aluminum alloy using the ultrasonic surface rolling process (USRP). The surface morphology, surface roughness, microstructure, hardness, and corrosion resistance of 6061 aluminum alloy were systematically characterized using X-ray diffraction (XRD), laser scanning confocal microscopy (LSCM), optical microscope(OM), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), and other testing methods. The results showed that ultrasonic surface rolling strengthening did not change the surface phase composition of 6061 aluminum alloy. It changed the size of the surface phases and the distance between the phases while refining the surface grains. The static pressures has a great influence on the surface properties of 6061 aluminum alloy. The best surface properties were obtained under 500N static pressures. The surface hardness reached 129.5HV0.5, the surface morphology was flat and continuous, the surface roughness was reduced to Ra0.191μm, and the corrosion resistance was significantly improved

Solar-thermal conversion and steam generation: a review

Recently, steam generation systems based on solar-thermal conversion have received much interest, and this may be due to the widespread use of solar energy and water sources such as oceans and lakes. The photo-thermal desalination system becomes attractive as it can convert absorbed solar light energy into thermal energy and realise the desalination and water purification of saline water through the evaporation process. In this paper, the research status of solar-thermal conversion materials such as metal-based materials, semiconductor materials, carbon-base materials, organic polymer materials, composite photo-thermal materials and their solar-thermal conversion mechanism in recent years are reviewed. The physical process and evaluation principle of solar-thermal conversion are both carefully introduced. The methods of optimising thermal management and increasing the evaporation rate of a hybrid system are also introduced in detail. Four main applications of solar-thermal conversion technologies (seawater desalination, wastewater purification, sterilisation and power generation) are discussed. Finally, based on the above analysis, the prospects and challenges for future research in the field of desalination are discussed from an engineering and scientific viewpoint to promote the direction of research, in order to stimulate future development and accelerate commercial application

Association between the PDE4D gene and ischaemic stroke in the Chinese Han population

A B S T R A C T Recent findings suggests that PDE4D (gene encoding phosphodiesterase 4D) is a stroke-related gene in the Icelandic population, but it is still very controversial as to whether it is a susceptible gene for stroke in other populations. In the present study, we attempted to explore the role of the gene in the pathogenesis of stroke in the Chinese Han population of eastern China. A total of 649 ischaemic stroke patients and 761 unrelated control individuals with no history of stroke or transient ischaemic attack were examined in a case-control study. Four SNPs (single nucleotide polymorphisms) rs152312 (C/T), SNP56 (A/T), SNP83 (C/T) and SNP87 (C/T) with a minor allele frequency over 5 % were genotyped and the corresponding haplotypes were constructed. In an analysis of the combined cardiogenic and carotid stroke group, both the allele (P = 0.0060) and genotype (P = 0.0160) frequencies between cases and controls at SNP83 showed significant differences. However, no difference in haplotype frequencies was observed between cases and controls at rs152312 and SNP56. In the analysis of the small-artery-occlusive stroke group, no difference in allele or genotype frequencies was observed at any marker between cases and controls; the global haplotype frequency in rs152312 and SNP56 had a significant difference between cases and controls (P = 0.0162); the frequency of haplotype C-A was higher in cases than in controls (P = 0.0122). In conclusion, our present findings show that polymorphisms in the PDE4D gene are associated with an increased risk of ischaemic stroke in the Chinese Han population. The present study adds further support to the role of PDE4D in stroke

The Work of Making Facial Recognition Work

Facial recognition technology (FRT) has become a significant topic in CSCW owing to widespread adoption and related criticisms: the use of FRT is often considered an assault on privacy or a kind of neo-phrenology. This discussion has revolved around uses of FRT for identification, which are often non-voluntary, in particular for surveillance wherein people are (by and large) unwittingly recognized by FRT systems. At the same time, we have also seen a rise of forms of FRT for verification (e.g., passport control or Apple’s Face ID), which typically are overt and interactive. In this paper we study an interactive FRT system used for guest check-in at a hotel in China. We show how guests and bystanders engage in ‘self-disciplining work’ by controlling their facial (and bodily) comportment both to get recognized and at times to avoid recognition. From our analysis we discuss the role of preparatory and remedial work, as well as dehumanization, and the importance of CSCW paying closer attention to the significance of interactional compliance for people using and bystanding facial recognition technologies

Global asymptotic stability of high-order Hopfield type neural networks with time delays

AbstractThis paper studies the problem of global asymptotic stability of a class of high-order Hopfield type neural networks with time delays. By utilizing Lyapunov functionals, we obtain some sufficient conditions for the global asymptotic stability of the equilibrium point of such neural networks in terms of linear matrix inequality (LMI). Numerical examples are given to illustrate the advantages of our approach

Seismic Design Strategy of Cable Stayed Bridges Subjected to Strong Ground Motions

SUMMARY: One typical medium span cable stayed bridge is selected to investigate its nonlinear plastic behavior and the effect on the seismic responses of other structural components. The nonlinear behavior is considered by different type of plastic elements based on the ratio of sectional capacity to linear seismic demand. A series of nonlinear time history analysis is then carried out under strong earthquake inputs with increasing intensities. The result shows that the yield sequence of the pylon columns and auxiliary piers may be different due to different ground motions and even under the same ground motion but with different intensities; meanwhile significant force redistribution is observed in columns owing to the yielding in plastic regions, however, the pylon still conserves certain plasticity margin according to the current design practice in China, which indicates the pylon limited ductility design might be an practical alternative subjected to strong ground motions