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The evolution of dissipation energy of the uniaxial and multiaxial fatigue experiments on the automobile sealant adhesively bonded butt joints was investigated by the method of fatigue dissipation ...

The evolution of dissipation energy of the uniaxial and multiaxial fatigue experiments on the automobile sealant adhesively bonded butt-joints was investigated by the method of fatigue dissipation energy analysis and fatigue failure identification. The results demonstrated that the dissipation energy increased and the fatigue life decreased with the increase of stress amplitude, mean stress, and the decrease of cycle time. Meanwhile, the non-proportional loading path resulted in greater dissipation energy and shorter fatigue life than that of uniaxial and proportional loading path. Moreover, the existing energy-based model using the energy dissipated in different cyclic loading stages as the fatigue parameters was adopted to predict the fatigue life of the automobile sealant adhesively bonded butt-joints, respectively. The practical limitations of the prediction model using the total dissipation energy as the fatigue parameter were evaluated. Therefore, an improved energy-based fatigue life prediction model was proposed which using the partial steady stage of dissipation energy curves as the parameters. The predicted results of the improved model and the comparison with that of the existing energy-based model indicated that the improved model had an excellent ability to predict the fatigue life, and was more practical in engineering application for the automobile sealant adhesively bonded butt-joints.

In order to investigate the effects of temperature, humidity and strain rate on the mechanical properties of silane-modified polyurethane sealant, the humidity experiments and uniaxial tensile experiments at different testing conditions were conducted. The experimental results indicate that the mechanical properties exhibit nonlinear and dependence on temperature, humidity and strain rate. However, it exhibits rate independence at higher temperature and higher degree of humidity. The degree of humidity of the material is related to the immersion temperature and immersion time in the water bath. Furthermore, it is also observed that the tensile strength, elastic modulus and fracture strain of the materials are sensitive to the temperature, humidity and strain rate. Considering the effects of temperature, humidity and strain rate, a nonlinear constitutive model is developed to describe the tensile deformation behavior of the silane-modified polyurethane sealant. Comparisons between the model calculated and the experimental results show that the developed model has an accurate description to the tensile deformation behavior of the silane-modified polyurethane sealant under different testing conditions.

Angiotensin II (AngII)-induced production of inflammatory factors and proliferation in vascular smooth muscle cells (VSMCs) play an important role in the progression of atherosclerotic plaques. Growing evidence has demonstrated that activation of peroxisome proliferator-activated receptor-γ (PPAR-γ) effectively attenuates AngII-induced inflammation and intercellular reactive oxygen species (iROS) production. Curcumin (Cur) inhibits inflammatory responses by enhancing PPAR-γ activity and reducing oxidative stress in various tissues. The aim of the present study was to ascertain whether Cur inhibits AngII-induced inflammation and proliferation, and its underlying molecular mechanism, in VSMCs. Enzyme-linked immunosorbent assay (ELISA) and real-time PCR were used to measure the protein and mRNA expression of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Nitric oxide (NO) production was measured by Griess reaction. Western blot analysis and a DNA-binding assay were used to measure PPAR-γ activity. iROS production was measured using the DCFH-DA method. In rat VSMCs, Cur attenuated AngII‑induced expression of IL-6 and TNF-α mRNA and protein in a concentration-dependent manner, inhibited NO production by suppressing inducible NO synthase (iNOS) activity, and suppressed proliferation of VSMCs. This was accompanied by increased PPAR-γ expression and activation in Cur-pretreated VSMCs. GW9662, a PPAR-γ antagonist, reversed the anti-inflammatory effect of Cur. Moreover, Cur attenuated AngII-induced oxidative stress by downregulating the expression of p47phox, which is a key subunit of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. In conclusion, Cur inhibited the expression of IL-6 and TNF-α, decreased the production of NO, and suppressed the proliferation of VSMCs, by elevating PPAR-γ activity and suppressing oxidative stress, leading to attenuated AngII-induced inflammatory responses in VSMCs.

The multiaxial fatigue experiments were conducted on the adhesive bonded hollow cylinder butt-joints under the stress-controlled mode. The effect of loading path, equivalent stress amplitude, equivalent mean stress and period on the multiaxial fatigue behaviors were discussed. The multiaxial fatigue damages of adhesively bonded joints were also analyzed from the evolution of ratchetting and dissipative energy behavior. The results showed that the loading paths had a great influence on dissipated energy and ratchetting strain, and the effects of non-proportional loading path on the ratchetting strain and dissipation energy were greater than that of the proportional loading path. Moreover, the equivalent stress amplitude, equivalent mean stress and period all had some influence on the dissipation energy and equivalent ratchetting strain. In addition, the dissipative energy and the ratchetting strain increased gradually with the number of cycle increase, which resulted in the fatigue life decreases with the increase of equivalent stress amplitude and mean stress, and the decreasing period. The effects of period on the multiaxial fatigue life under the elliptic loading path were insignificant for the adhesive bonding butt-joints.

The multiaxial fatigue experiments were conducted on the silicone seal adhesive bonding hollow cylinder butt-joints under the stress-controlled mode at laboratory ambient temperature. The effect of loading path, equivalent stress amplitude, equivalent mean stress and cycle time on the multiaxial ratchetting behaviors and fatigue life were discussed. The experimental results showed that the effects of non-proportional loading path on the ratchetting strain were greater than that of the proportional loading path. Moreover, the effects of the normal stress on the ratchetting strain were relatively larger than that of the equivalent shear stress under the multiaxial loading paths. In addition, the ratchetting strain increases and fatigue life decreases with the increase of equivalent stress amplitude and mean stress, and the decreasing cycle time. The effects of cycle time on the multiaxial ratchetting strain and fatigue life under the elliptic loading path were insignificant for the silicone seal adhesive bonding butt-joints.

Uniaxial and multiaxial low-cycle fatigue experiments were conducted on the automobile sealant adhesive bonding hollow cylindrical butt-joints under stress-controlled mode, and the effects of equivalent stress amplitude, equivalent mean stress and loading frequency on the fatigue life of specimens were analyzed. The experimental results showed that the fatigue life of uniaxial tensile cycle was shorter than that one of uniaxial torsion cycle. The fatigue life of the automobile sealant adhesive bonding butt-joints decreased with the increase of equivalent stress amplitude, mean stress, loading frequency. The fatigue life of the non-proportional loading path was shorter than that of the proportional loading path. In addition, a modified stress-based fatigue life prediction model was proposed that collectively considered the effect of loading path, equivalent stress amplitude, equivalent mean stress and loading frequency on the multiaxial fatigue life. The comparisons of the predicted results and the experiment life indicated that the modified fatigue life prediction model had good prediction ability for the multiaxial fatigue life of the sealant adhesive bonding butt-joints.

In order to investigate the uniaxial ratchetting behaviors and fatigue failure of silicone seal adhesive bonded hollow cylinder butt-joints under uniaxial tensile and torsional cyclic loading, the effects of stress amplitude, mean stress, cycle time and loading history on the ratchetting strain, ratchetting strain rate and fatigue life were discussed respectively. The experimental results show that ratchetting strain appeared in both tensile and torsional cyclic loading. The ratchetting strain of tensile cycle evolved in three stages, while that of torsion cycle evolved in two stages. Furthermore, the effect of uniaxial tensile cycle on ratchetting strain is greater than that of uniaxial torsion cycle, and the fatigue life of torsion cycle is higher than that of tensile cycle. The stress amplitude, mean stress and cycle time have influence on the ratchetting strain, ratchetting strain rate and fatigue life of the adhesively bonded butt-joints. The ratchetting strain and ratchetting strain rate increase, and the fatigue life decreases with the increase of stress amplitude and mean stress, or the decrease of cycle time. In addition, it is also found that silicone seal adhesive bonded butt-joint has a strong memory of loading history for the stress amplitude. Prior stress cycle with higher stress amplitude restrains the ratchetting strain in subsequent cycle with lower stress amplitude.

Ratcheting and low-cycle fatigue failure behaviors of the adhesively bonded hollow cylindrical butt-joints has been experimentally investigated. A series of uniaxial cyclic tension experiments were carried out under stress-controlled mode. The effects of stress amplitude, mean stress and cycle time on the uniaxial ratcheting response, fatigue damage variable evolution and fatigue life of the adhesively bonded butt-joints were analyzed. The results show that the ratcheting strain, ratcheting strain rate and fatigue damage variable all increase with the increase of stress amplitude and mean stress. The shorter cycle time results in the increase of fatigue damage variable and the degradation of the stiffness of the adhesive material. It is also found that the increase of stress amplitude and mean stress can reduce the low-cycle fatigue life. Meanwhile, the fatigue life increases with the increase of cycle time for the adhesively bonded butt-joints.

With the development of science and technology and urbanization process in depth, rail transit plays a more and more important role in the city. Train-ground communication is an important part of the safe operation of the rail transit trains. According to the traits of wireless train-ground communication, this paper proposes a high reliability wireless coverage technology solution to rail transit communication. Then this paper introduces the implementation process of the solution and verifies the wireless coverage range in this solution.

Objectives Obstructive sleep apnea (OSA) is an emerging risk factor for cardiovascular disease. Microcirculatory dysfunction has been proposed as a potential mechanism in the pathogenesis of cardiovascular disease in OSA. This study aims to investigate the relationship between OSA and coronary microcirculatory function. Patients and methods One thousand and thirty-eight patients (598 female, mean age 60±9 years) with angiographically normal coronary arteries were divided into three groups with non-OSA of apnea-hypopnea index (AHI) less than 5 (n=403), mild-to-moderate OSA of AHI 5-30 (n=386), and severe OSA of AHI more than 30 (n=249). Results The prevalence of OSA was very high in patients with syndrome X (635/1038). Patients with higher AHI values had a lower coronary flow reserve, were more likely to have a higher total cholesterol, low-density lipoprotein cholesterol, and high sensitive C-reactive protein, and were more likely to be obese. Compared with the non-OSA group, the multivariable-adjusted odds ratio of coronary microcirculatory function for an AHI of 5-30 events/h was 1.93, 95% confidence interval 1.66-3.47, P=0.038, and for an AHI of more than 30 events/h was 2.18, 95% confidence interval 1.62-4.23, P=0.024, in model 1; and coronary microcirculatory function for an AHI of 5-30 events/h and more than 30 events/h odds ratio 1.31, 95% confidence interval 1.06-2.88, P=0.043, versus odds ratio 2.08, 95% confidence interval 1.03-2.16, P=0.036, in model 2. Conclusion As compared with having no sleep apnea, categories with higher AHI were associated with increased odds of lower coronary flow reserve. The data suggested a close relationship between OSA and coronary microcirculatory function in atherosclerosis.

Remote sensing satellite images can intuitively reflect the information of the Earth's surface. The computer image processing system is of the advantages of high-precision and low-cost. It has a strong application value to study the computer processing system of remote sensing satellite image. The paper first discussed the design principles of the computer processing system and the implementation of its workflow, and then the application of the image processing system is briefly analyzed.

Adaptive learning system has been developed maturing. But the formulation and selection of learning scheme in the learners' personality characteristic mining is still not satisfactory. The adaptive learning scheme with specific learner characteristics personalized will have positive effect for the learner on learning effect. The emergence of adaptive learning system based on network, making the learning is no longer affected by time and space restrictions, and the teachers teaching mode is changing to students' learning mode. The prior paper had given a brief introduction for adaptive learning system. Then in this paper we will focus on the designed theoretical knowledge of the adaptive learning system and give the design scheme.

A moderately halophilic bacteria designed strain NY-011(T) was isolated from the high salt culture of Dunaliella salina in Chengdu of Sichuan Province, China. The isolate was Gram-negative, nonmotile, rod-shaped and 12.5-21.6 μm in length. Colonies on solid media are circular, wet, smooth and cream. The strain grew optimally at 37 °C, pH 7.0 and in the presence of 8 % NaCl. Acid was produced from glycerol, D-arabinose, glucose, trehalose, inositol, mannose, mannitol, sucrose, maltose and sorbitol. Catalase is produced but not oxidase. The major fatty acids are C18: 1ω7c (37.59 %), C19: 0 cyclo ω8c (18.29 %), C16: 0 (16.05 %) and C6: 0 (12.43 %). The predominant respiratory lipoquinone found in strain NY-011(T) is ubiquinone with nine isoprene units (Q-9). The genomic DNA G + C content of strain NY-011(T) was 62.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain NY-011(T) belonged to the genus Halomonas. The highest levels of 16S rRNA gene sequence similarity were found between the strain NY-011(T) and H. pantelleriensis (sequence similarity 98.43 %). However, the levels of DNA-DNA relatedness between them were only 23.1 %. In addition, the strain NY-011(T) had a phenotypic profile that readily distinguished it from H. pantelleriensis. The strain NY-011(T) therefore represents a new species of the genus Halomonas, for which the name Halomonas socia sp. nov. is proposed, with NY-011(T) (=CCTCC AB 2011033(T) = KCTC 23671(T)) as the type strain.

Multivariate quadratic based public-key cryptography called MQ problem which based on calculation of a secure cryptography of multivariate equations and MQ cryptography security is based on the difficulty of the solution of multivariate equations. But computer and mathematician scientists put a lot of effort and a long time to research MQ cryptography and they have proved that MQ cryptography is NP complete problem. Therefore, before the P problem Equal to the NP problem we do not figure out selected multivariate equations by random in polynomial time. So we can use this feature to construct the relative safety method of the public key encryption. A new type of public-key cryptosystem has been brought up in this paper that one-way shell core function which has such advantages as more security and flexibility, and provides a more inclusive public-key cryptosystem.

The robotics solution to Lamport clocks is defined not only by the construction of multicast systems, but also by the extensive need for RAID. after years of essential research into flip-flop gates, we confirm the development of IPv7, which embodies the important principles of robotics. Lyno, our new system for the analysis of Markov models, is the solution to all of these obstacles.

BACKGROUND Tanshinone IIA (TSN) is one of the main components isolated from Danshen, which is widely used for the treatment of cardiovascular diseases. The transforming growth factor beta (TGF-β) signaling pathway and microRNA (miR)-29b play important roles in the progression of cardiac fibrosis and the modulation of cardiac fibroblast (CF) function. Our study investigated the role of miR-29b in the cardioprotective effects of TSN in postinfarct cardiac remodeling. METHODS AND RESULTS Echocardiography demonstrated that medium-dose TSN (TSN-M) and high-dose TSN (TSN-H) significantly inhibited postinfarct cardiac fibrosis and improved the impaired left ventricular function in rats subjected to acute myocardial infarction. Moreover, quantitative real-time polymerase chain reaction and Western blot demonstrated that TSN-M and TSN-H downregulated the expression of TGF-β1, Col1a1, Col3a1, and α-SMA but upregulated the expression of miR-29b. CFs treated with TSN showed inhibited TGF-β signaling pathway, downregulated expression of Col1a1, Col3a1, and α-SMA, and upregulated miR-29b expression in vitro. Furthermore, treatment with a miR-29b inhibitor dramatically inhibited these TSN-induced antifibrotic effects, suggesting that miR-29b may be responsible for the antifibrotic effects of TSN. In addition, treatment with Smad3 siRNA significantly inhibited miR-29b expression in CFs, which implies that Smad3 signaling promotes miR-29b expression on CFs. CONCLUSIONS TSN exerts antifibrotic effects in postinfarct cardiac fibrosis by upregulating the expression of miR-29b, which is mediated by the TGF-β-Smad3 signaling pathway.

To observe the effect of medicinal-cake-separated moxibustion combined with acupuncture on back-leg activities and plasma substance P (SP) levels in patients with lumbar disc herniation, so as to reveal its mechanism underlying pain relief.A total of 114 patients with lumbar disc herniation were randomly divided into control group (n=56) and treatment group (n=58) according to a random digits table. Patients of the control group were treated by manual acupuncture stimulation of main acupoints Jiaji (EX-B 2), Huantiao (GB 30, affected side), Chengshan (BL 57, affected side), Kunlun (BL 60, affected side), and supplemented acupoints Yanglingquan (GB 34), Weizhong (BL 40) and Zusanli (ST 36) in combination with wheat-flour-cake separated moxibustion at the main acupoints, and patients of the treatment group were treated by medicinal-cake [Chuanwu (Radix Aconiti), Caowu (Radix Aconiti Kusnezoffii), Ruxiang (Olibanum), etc. ]-separated moxibustion in combination with manual acupuncture stimulation of the same acupoints mentioned above. Acupuncture treatment was conducted for 30 min, followed by moxibustion for 15 min. The treatment was given once daily for 10 days. The patients' back-leg functional activity ability was assessed using straight-leg raising test, and the pain state assessed using visual analogue scale (VAS) and Japanese Orthopaedic Association (JOA) scores, respectively. The therapeutic effect was evaluated by using "Crite- ria for Diagnosis and Outcome Evaluation of Clinical Disorders or Syndromes of Chinese Medicine" issued in 1994 and plasma SP content was detected by radioimmunoassay.After the therapy, the back-leg activity score and JOA score of both groups were significantly higher than those of pre-treatment in the same one group (P0. 05, P0. 01), and those of the treatment group were significantly higher than those of the control group (P0.05). The VAS score of the treatment group was re- markably lower than that of the control group (P0. 01). After the treatment, the plasma SP content was markedly lower in the treatment group than in the control group (.P0O. 05 ) .Medicinal-cake-separated moxibustion therapy can ame- liorate pain severity and functional activity of the back-leg pain patients with lumbar disc hernia, which may be related to its effect in reducing blood SP level.

Systemic rotenone models of Parkinson's disease (PD) are highly reproducible and may provide evidence on the pathogenesis of PD. In the present study, male Sprague-Dawley rats (1-year-old) were subcutaneously administered with rotenone (1.5 mg/kg/day) for six days and observed for the following three weeks. Compared with the control rats, a significant decrease was observed in the body weight and a marked increase was observed in the areas under the behavioral scoring curves in the rotenone-treated rats. Immunohistochemical staining revealed that the abundance of nigral tyrosine hydroxylase (TH)-positive neurons was markedly reduced following rotenone treatment. ELISA and neurochemical assays demonstrated a significant increase in the levels of nitric oxide (NO) and NO synthase, whereas a marked decrease was observed in the thiol levels in the brains of the rotenone-treated rats. Thus, subacute rotenone treatment was found to induce behavioral deficits and the loss of nigral TH-positive neurons which may be associated with the excessive levels of NO in the rat brains.

This paper explores the gray system theory and mathematical morphology in image edge detection and target recognition applications. Through experiments that ingenious combination of the gray system theory and mathematical morphology, the use of gray system theory to extract the edge of the image for the conditions, the multi-level geodetic expansion to expand to fill the target area, through which the algorithm can improve the detection of image accuracy, enhanced noise immunity, effectively identify the target.

Considering small edges, spurious edges and other problems of edge detection on SAR images, an improved edge detection algorithm based on fuzzy enhancement of transition region is proposed. In this paper, the defects of the classical fuzzy enhancement algorithm is analyzed, and by researching on the characters of target and background image, the concept of the transition zone is introduced into the image enhancement field, and then an improved edge detection algorithm is proposed based on this. The experimental results show that this algorithm can overcome the shortcomings caused by the inappropriate choice of crossover point, extract greater information of the targets' edges and move some redundancy information of small edges effectively. It is applicable to the SAR images with abundant topic targets.

Osteopontin (OPN) has close relationship with metastasis in hepatocellular carcinoma but its downstream signal pathways have not been well defined in hepatocellular carcinoma. The object of this study is to identify the associated signal pathways in human HCC tissues. The expressions of OPN, intergrin aV, CD44v6, P-FAK, FAK, P-Src, Src, P-ERK and P-AKT were assayed using TMA analysis. The relationship of OPN with P-ERK, P-Src and P-AKT were explored and the role in HCC metastasis was analysed. The expression levels of OPN, intergrin aV, CD44v6, P-FAK, P-Src, Src, P-ERK and P-AKT in HCC tissue were significantly higher than that in normal tissue (P value is less than 0.05). No significant difference was found between the expression levels of FAK in HCC tissue and normal tissue (P value is more than 0.05). OPN expression was significantly associated with Integrin av (P value is less than 0.01), CD44V6 (P value is less than 0.01) and P-ERK (P value is less than 0.05) but not with P-Src, P-FAK and P-AKT (P value is more than 0.05). The expressions of P-FAK (P value is less than 0.05), P-Src (P value is less than 0.01) and P-AKT (P value is less than 0.05) were significantly associated with Integrin av and the P-FAK expression was also significantly associated with CD44V6 (P value is less than 0.01). OPN promotes HCC metastasis though Integrin av/CD44V6/MAPK pathway in human HCC.

To construct an cell penetrating peptide-based expression vector capable of targeted delivery of proteins into the cell nuclei and study its function of protein transduction.The fusion protein expression vector pET14b-HC(L)NE (pET14-b-His-CPP-Linker-NLS-EGFP) incorporating cell penetrating peptide (CPP), nuclear localization signal(NLS), linker and enhanced green fluorescent protein (EGFP) was constructed based on His-tagged pET14b-HE (pET14b-His-EGFP) by site-directed mutagenesis PCR method. After identification by enzyme digestion and DNA sequencing, the recombinant plasmid was transformed into BL21(DE(3)) strain. The HC(L)NE fusion protein was expressed following IPTG induction and purified with Ni(2+)-NTA affinity chromatography. After dialysis and filtration, the HC(L)NE fusion protein was added into cultured eukaryotic cells. The protein transduction in the living cells was observed under fluorescence microscope and analyzed by Western blotting.Enzyme digestion and DNA sequencing confirmed successful construction of the pET14b-HC(L)NE vector, and the fusion protein efficiently expressed in E. coli. Protein transduction experiments in eukaryotic cells revealed that the fusion protein could rapidly penetrate the cell membrane and reach the cell nucleus, and this internalization was time- and concentration-dependent.The cell penetrating peptide-based expression vector for targeted protein delivery to the cell nucleus has been successfully constructed, and a transport system that can delivery exogenous proteins or polypeptides into the cytoplasm and cell nucleus is established, which provides an economical and efficient means for functional study of the proteins and polypeptide in cells and targeted drug delivery.

To explore the reasons for the low intracellular transduction efficiency of a previously constructed His-TAT-Flag recombinant protein and establish a more efficient transduction system.The Flag tag of pET14b-His- Tat-Flag vector was deleted with PCR mutant kit, and enhanced green fluorescent protein (EGFP) coding sequence was inserted into the new pET14b-His-TAT recombinant vector. Enzyme digestion and DNA sequencing were performed for identification of pET14b-His-TAT-EGFP vector, which was then transformed into E. coli BL21(DE(3)). After IPTG induction, the recombinant protein of His-TAT-EGFP was isolated and analyzed with SDS-PAGE. Purified His-TAT-EGFP recombinant protein was added to ECV304 cells and the fluorescence was observed to evaluate the transduction efficiency.pET14b-His-TAT vector and pET14b-His-TAT- EGFP vector were successfully constructed, which was identified with enzyme digestion and DNA sequencing. His-TAT-EGFP fusion protein was expressed and purified successfully and showed cellular transduction activity.The prokaryotic expression vector has been successfully constructed by modifying pET14b-His-TAT-Flag, and the expressed and purified recombinant protein of His-TAT-EGFP possesses high efficiency of intracellular transduction activity.