Structural damage assessment using principal component analysis

A novel structural damage assessment technique based on the principal component analysis (PCA) and the flexibility matrix approach is proposed in this paper. The technique is a model free method and can be used for detecting damage occurrence and location. The PCA is adopted firstly to decompose a set of correlated structural response measurements into statistically uncorrelated ones. Under the condition of small damping, these uncorrelated data can be shown to be related to modal responses and can be used to estimate the modal properties of a structure. The structural flexibility matrix can then be constructed using the estimated modal parameters. The change in the flexibility matrix gives an indication of the occurrence and location of structural damage. A numerical study on a 7-storey shear beam building model is performed to illustrate the applicability of the proposed technique. The results show that the proposed technique can accurately identify the occurrence and location of structural damage when the building is subjected to various earthquake excitations

Ion-implantation treatment (Ba, Sr)TiO3 thin films

The effects of ion-implantation on the properties of spin-on sol-gel (Ba, Sr),TiO3 (BST) thin films were studied by implanting with Ar+, N+ and F+ doses. The F+ implanted BST samples present better electrical and dielectric properties than the A(+) or Nt implanted BST do. The pronounced thickness shrinkage was observed in BST films after the F+ implantation (before annealing treatment) and a respective increase in the refractive index was measured. After the implanted samples are annealed, the changes of thickness and refractive index depend on the concentration of the implanted dose. If the F+ implanted dose is low (similar to5 x 10(14) cm(-2)), the BST preserves the densification propel-ties. Its refractive index increases to 2.23 and it also presents a high dielectric constant of about 520. If the F+ implanted dose is high (greater than or equal to similar to1 x 10(15) cm(-2)), excess F+ ions form Sr or Ba bondings with F+. This will degrade the material, electric and dielectric properties. The corresponding dielectric constant is about 440. An infrared transmission study of the samples suggests that the ion-implanted sample with lower doses have fewer -OH contaminants than the non-implanted or implanted samples with high doses. Based on the results presented, it was concluded that suitable ion-implantation densifies the spin-on sol-gel BST films and reduces the -OH contaminants in the films

Early life environmental and pharmacological stressors result in persistent dysregulations of the serotonergic system

10.3389/fnbeh.2015.00094Frontiers in Behavioral Neuroscience9AP

Efficient Bacillus subtilis promoters for graded expression of heterologous genes in Escherichia coli

A variant of the veg I promoter (abbreviated vegA P in this work), designated vegG P, was isolated from its natural host, Bacillus subtilis and characterized to contain a spontaneous A to G transition mutation at the -11 position of the -10 region of vegA P. The mutant promoter functioned well to provide efficient transcription of foreign genes in B. subtilis. Moreover, despite its origin from a gram-positive bacterium, veg G P was found to facilitate efficient gene expression in E. coli and was shown to mediate thus far the highest level of expression of the reporter protein, an endoglucanase (Eng) encoded by the cenA gene of Cellulomonas fimi. Surprisingly, vegG P was also shown to function more efficiently than one of the strongest E. coli promoters, tac (tac P) in E. coli, as judged by Northern blot analysis and excretory expression of Eng. Two derivatives of vegG P, designated vegC P and vegT P, together with the wild-type promoter, vegA P, were also found to be more efficient than tac P to express excretory Eng in E. coli, despite at lower efficiencies than that of vegG P. These four B. subtilis promoters, which were shown to exhibit different transcriptional efficiencies, may be employed for stepwise or graded gene expression in E. coli, thereby facilitating the task of fine tuning to achieve "optimal" expression of the target gene, which appears to be a crucial milestone for the maximum production of the desired protein in the culture medium

A Cross-Cultural Study of the Back Pain Beliefs of Female Undergraduate Healthcare Students

Objectives: To determine if country (Australia, Taiwan, Singapore), undergraduate healthcare course (physiotherapy, nursing), low back pain (LBP) history, and year of course influenced various back pain beliefs in undergraduate female healthcare students. Methods: Three hundred and 82 female undergraduate nursing and physiotherapy students completed questionnaires examining; the inevitability of future life with low back trouble, the LBP beliefs held by healthcare providers and fear avoidance beliefs related to physical activity. Also participants completed questionnaires to determine their LBP status. General linear models were used to determine whether differences existed for back beliefs scores. Results: Differences were evident in the future consequence of LBP between countries (P\u3c0.001), undergraduate course (P\u3c0.001), and LBP status (P=0.021). Healthcare provider beliefs were found to be significantly influenced by course only (P\u3c0.001). Fear avoidance beliefs related to physical activity were influenced by country (P=0.002) and undergraduate course (P\u3c0.001). When compared with white Australians, Taiwanese and Singaporean Chinese displayed more negative back beliefs regarding the future consequence of LBP (P\u3c0.001) and more fear avoidant beliefs toward physical activity (P=0.021 and P\u3c0.001, respectively). Further, nursing students had more negative back pain beliefs than physiotherapy students (P\u3c0.001) and, the experience of LBP was associated with more positive beliefs on the future consequence of back trouble (P=0.021). Discussion: Findings of this study highlight the importance of country, education, and LBP experience on back pain beliefs. The more negative back pain beliefs found in Taiwan and Singapore may reflect current pain beliefs and management attitudes

Effects of fluorine-implanted treatment on Ba0.7Sr0.3TiO3 films

The effects of F-ion implantation on the leakage and dielectric properties of the Ba0.7Sr0.3TiO3 (BST) films were investigated. The BST film implanted with 1 x 10(15) cm(-2) shows the optimum leakage performance. The leakage current density can be decreased by one order of magnitude as compared to that of the non-implanted sample at an applied voltage of 2 V. On increasing the implanted dose from 5 x 10(14) to 5 x 10(15) cm(-2), the dielectric constant first increases and then decreases due to the deteriorated crystallinity. It is found that the suitable F-ion dose can reduce the -OH contaminants and improve the dielectric and leakage properties. (C) 2000 Elsevier Science Ltd. All rights reserved

Ion-implanted treatment of (Ba, Sr)TiO3 films for DRAM applications

The effects of ion implantation on the properties of spin-on sol-gel Ba0.7ST0.3TiO3 (BST) thin films were studied by implanted Ar+, N+, and F+ doses. The F+-implanted BST samples present leakage current density 450. The leakage current of F+-implanted BST samples was reduced about one order of magnitude as compared with that of samples with implanted Ar+, N+ or without implantation. The thickness shrinkage from 135 to 115 nm was observed in F+-implanted BST films (before annealing treatment) and a respective increase in the refractive index from 1.84 to 2.05 was measured. After annealing the implanted samples, the changes of thickness and refractive index depend on the concentration of implanted dose. Based on an infrared transmission study of the samples we suggest that the ion-implanted samples with smaller dose (5 x 10(14) cm(-2)) have fewer -OH contaminants than the non-implanted or implanted samples with the larger doses (greater than or equal to1 x 10(15) cm(-2)). Based on the results presented, we conclude that suitable ion implantation densities the spin-on sol-gel BST films and reduces the -OH contaminants in the films. (C) 2001 Elsevier Science B.V. All rights reserved

Transcriptome alterations of vascular smooth muscle cells in aortic wall of myocardial infarction patients

10.1016/j.dib.2018.01.108Data in Brief171112-113

Characterization of NH3 plasma-treated Ba0.7Sr0.3TiO3 thin films

The effects of plasma surface treatment, using NH3 gas, of Ba0.7Sr0.3TiO3 (BST) films on the leakage and dielectric characteristics of a Pt/BST/Pt capacitor were investigated. As a result of the exposure of BST to the plasma, the leakage current density of the BST capacitor can be improved by three orders of magnitude as compared to that of the nonplasma-treated sample at an applied voltage of 1.5 V. Nevertheless, the surface morphology of BST was also changed by the NH3 plasma, as explored by atomic force microscopy. From the X-ray photoelectron spectroscopy examination, the existence of the N 1 s peak was observed in the plasma-treated sample. It induces the additional space charge and results in the reduction of the dielectric constant. (C) 2000 Elsevier Science Ltd. All rights reserved

The guanosine tetraphosphate (ppGpp) alarmone, DksA and promoter affinity for RNA polymerase in regulation of σ54-dependent transcription

The RNA polymerase-binding protein DksA is a cofactor required for guanosine tetraphosphate (ppGpp)-responsive control of transcription from sigma70 promoters. Here we present evidence: (i) that both DksA and ppGpp are required for in vivo sigma54 transcription even though they do not have any major direct effects on sigma54 transcription in reconstituted in vitro transcription and sigma-factor competition assays, (ii) that previously defined mutations rendering the housekeeping sigma70 less effective at competing with sigma54 for limiting amounts of core RNA polymerase similarly suppress the requirement for DksA and ppGpp in vivo and (iii) that the extent to which ppGpp and DksA affect transcription from sigma54 promoters in vivo reflects the innate affinity of the promoters for sigma54-RNA polymerase holoenzyme in vitro. Based on these findings, we propose a passive model for ppGpp/DksA regulation of sigma54-dependent transcription that depends on the potent negative effects of these regulatory molecules on transcription from powerful stringently regulated sigma70 promoters