Signature of structure failure using asymmetric and broadening factors of brillouin spectrum

Copyright © 2005 IEEEWe introduce a novel data analysis approach based on the extraction of peak strain, asymmetric and broadening factors of the Brillouin spectrum measured with the distributed Brillouin sensor (DBS). Such an approach provides simultaneously global and local strains, describing the status of the structure, at the contrary of average strain measurements. These results are confirmed by a trial on a composite column subjected to vertical and bending loads. This demonstrates that the DBS is a powerful tool to give the signature of the structure failure and then to identify early problems in structures that none of existing point sensors can detect.Fabien Ravet, Xiaoyi Bao, Togay Ozbakkaloglu, and Murat Saatciogl

Axial compressive behavior of square and rectangular high-strength concrete-filled FRP tubes

This paper presents results of an experimental study on the behavior of square and rectangular high-strength concrete (HSC)-filled fiber-reinforced polymer (FRP) tubes (HSCFFT) under concentric compression. The effects of the tube thickness, sectional aspect ratio, and corner radius on the axial compressive behavior of concrete-filled FRP tubes (CFFT) were investigated experimentally through the tests of 24 CFFTs that were manufactured using unidirectional carbon fiber sheets and high-strength concrete with 78 MPa average compressive strength. As the first experimental investigation on the axial compressive behavior of square and rectangular HSCFFTs, the results of the study reported in this paper allow a number of significant conclusions to be drawn. First and foremost, test results indicate that sufficiently confined square and rectangular HSCFFTs can exhibit highly ductile behavior. The results also indicate that confinement effectiveness of FRP tubes increases with an increase in corner radius and decreases with an increase in sectional aspect ratio. It is also observed and discussed that HSCFFTs having tubes of low confinement effectiveness may experience a significant strength loss at the point of transition on their stress-strain curves. Furthermore, it is found that the behavior of HSCFFTs at this region differ from that of normal-strength CFFTs and that it is more sensitive to the effectiveness of a confining tube. Examination of the test results have also lead to a number of important observations on the influence of the key confinement parameters on the development and distribution of the hoop strains on the tubes of CFFTs, which are presented and discussed in the paper. © 2013 American Society of Civil Engineers.Togay Ozbakkalogl

Wellness through a comprehensive Yogic breathing program – A controlled pilot trial

<p>Abstract</p> <p>Background</p> <p>Increasing rates of psychosocial disturbances give rise to increased risks and vulnerability for a wide variety of stress-related chronic pain and other illnesses. Relaxation exercises aim at reducing stress and thereby help prevent these unwanted outcomes. One of the widely used relaxation practices is yoga and yogic breathing exercises. One specific form of these exercises is Sudarshan Kriya and related practices (SK&P) which are understood to have favourable effects on the mind-body system. The goal of this pilot study was to design a protocol that can investigate whether SK&P can lead to increased feeling of wellness in healthy volunteers.</p> <p>Methods</p> <p>Participants were recruited in a small university city in Sweden and were instructed in a 6-day intensive program of SK&P which they practiced daily for six weeks. The control group was instructed to relax in an armchair each day during the same period. Subjects included a total of 103 adults, 55 in the intervention (SK&P) group and 48 in the control group. Various instruments were administered before and after the intervention. Hospital Anxiety Depression Scale measured the degree of anxiety and depression, Life Orientation Test measured dispositional optimism, Stress and Energy Test measured individual's energy and stress experiences. Experienced Deviation from Normal State measured the experience of altered state of consciousness.</p> <p>Results</p> <p>There were no safety issues. Compliance was high (only 1 dropout in the SK&P group, and 5 in the control group). Outcome measures appeared to be appropriate for assessing the differences between the groups. Subjective reports generally correlated with the findings from the instruments. The data suggest that participants in the SK&P group, but not the control group, lowered their degree of anxiety, depression and stress, and also increased their degree of optimism (ANOVA; p < 0.001). The participants in the yoga group experienced the practices as a positive event that induced beneficial effects.</p> <p>Conclusion</p> <p>These data indicate that the experimental protocol that is developed here is safe, compliance level is good, and a full scale trial is feasible. The data obtained suggest that adult participants may improve their wellness by learning and applying a program based on yoga and yogic breathing exercises; this can be conclusively assessed in a large-scale trial.</p> <p>Trial Registration</p> <p>Australian Clinical Trial Registry ACTRN012607000175471.</p

3, 3′5 Triiodo L Thyronine Induces Apoptosis in Human Breast Cancer MCF-7cells, Repressing SMP30 Expression through Negative Thyroid Response Elements

Thyroid hormones regulate cell proliferation, differentiation as well as apoptosis. However molecular mechanism underlying apoptosis as a result of thyroid hormone signaling is poorly understood. The antiapoptotic role of Senescence Marker Protein-30 (SMP30) has been characterized in response to varieties of stimuli as well as in knock out model. Our earlier data suggest that thyroid hormone 3, 3'5 Triiodo L Thyronine (T(3)), represses SMP30 in rat liver.In highly metastatic MCF-7, human breast cancer cell line T3 treatment repressed SMP30 expression leading to enhanced apoptosis. Analysis by flow cytometry and other techniques revealed that overexpression and silencing of SMP30 in MCF-7 resulted in decelerated and accelerated apoptosis respectively. In order to identify the cis-acting elements involved in this regulation, we have analyzed hormone responsiveness of transiently transfected hSMP30 promoter deletion reporter vectors in MCF-7 cells. As opposed to the expected epigenetic outcome, thyroid hormone down regulated hSMP30 promoter activity despite enhanced recruitment of acetylated H3 on thyroid response elements (TREs). From the stand point of established epigenetic concept we have categorised these two TREs as negative response elements. Our attempt of siRNA mediated silencing of TRβ, reduced the fold of repression of SMP30 gene expression. In presence of thyroid hormone, Trichostatin- A (TSA), which is a Histone deacetylase (HDAC) inhibitor further inhibited SMP30 promoter activity. The above findings are in support of categorisation of both the thyroid response element as negative response elements as usually TSA should have reversed the repressions.This is the first report of novel mechanistic insights into the remarkable downregulation of SMP30 gene expression by thyroid hormone which in turn induces apoptosis in MCF-7 human breast cancer cells. We believe that our study represents a good ground for future effort to develop new therapeutic approaches to challenge the progression of breast cancer

Poverty in Consumer Culture:Towards a Transformative Social Representation

International audienceIn this article, we consider the representations of poverty within consumer culture. We focus on four main themes – social exclusion, vulnerability, pleasure and contentment – that capture some of the associations that contemporary understandings have made with poverty. For each theme, we consider the portrayals of poverty from the perspective of key agents (such as marketers, media, politicians) and then relate this to more emic representations of poverty by drawing on a range of contemporary poverty alleviating projects from around the world. We conclude with a set of guidelines for relevant stakeholders to bear in mind when elaborating their representations of poverty. These guidelines may act as a platform to transform marginalising representations of poverty into more empowering representations

FRP stay-in-place formwork for seismic resistant high-strength concrete columns

Fiber reinforced polymer (FRP) casings, in the form of stay-in-place formwork, provide an attractive alternative to conventional confinement reinforcement for concrete columns. These casings can fulfill multiple functions of; i) formwork, ii) confinement reinforcement, and iii) protective shell against corrosion, weathering and chemical attacks. This paper investigates the use of stay-in-place FRP formwork as concrete confinement reinforcement for HSC columns with circular and square crosssections. Large-scale specimens with 270 mm cross-sectional dimension and up to 90 MPa concrete strength, were tested under combined axial compression and incrementally increasing lateral deformation reversals. FRP casings were manufactured from carbon fiber sheets and epoxy resin. One of the square columns was provided with internal FRP crossties, a new technique introduced by the authors, to provide welldistributed lateral restraints along the column face, thereby improving the mechanism of confinement. The results indicate that the deformation capacity of HSC columns can be improved significantly by using FRP casings. The results further indicate that the confinement effectiveness of casings of square columns is significantly affected by the corner radius of casings. Confinement efficiency of these casings improves with the use of FRP crossties.T. Ozbakkaloglu and M. Saatciogluhttp://www.concrete.org/bookstorenet/ProductDetail.aspx?itemid=SP23

Rectangular Stress Block for High-Strength Concrete: A Comparative Study

http://cceds2005.mcmaster.ca/abstractbook.pd

Seismic performance of square high-strength concrete columns in FRP stay-in-place formwork

The use of high-strength concrete (HSC) in seismically active regions poses a major concern because of the brittle nature of the material. The confinement requirements for HSC columns may be prohibitively stringent since they require proportionately greater confinement than columns of normal-strength concrete. An alternative to conventional confinement reinforcement is the use of fiber reinforced polymer (FRP) casings, in the form of a stay-in-place formwork. This paper investigates the use of stay-in-place FRP formwork as concrete confinement reinforcement for HSC columns with square cross sections. Large scale HSC building columns, encased in FRP casings, were tested under simulated seismic loading. The columns had 270mm square sections and concrete strengths up to 90MPa. The casings were manufactured from carbon FRP and epoxy resin. The unique aspects of the test program were the introduction of the corner radius as a test parameter, and the presence of internally placed FRP crossties, integrally built with column casings, to improve the effectiveness of concrete confinement. Results indicate that the deformation capacity of HSC columns can be improved significantly by using FRP casings. The results further indicate that the confinement effectiveness of columns is significantly affected by the corner radius of casings. Additionally, the confinement efficiency can be improved with the use of FRP crossties. The columns developed inelastic drift capacities of up to 11%, demonstrating the usefulness of FRP stay-in-place formwork in improving deformability of HSC columns.Togay Ozbakkaloglu and Murat Saatciogl