Damage localization in laminated composite plates using mode shapes measured by pulsed TV holography

Three methods for the damage localization of impact damage in laminated composite plates, based on their vibrational characteristics, are presented in this paper. These methods use double pulse TV holography with acoustic excitation for mode shapes acquisition and the differences in translations, rotations and curvatures. The rotations and curvatures are obtained by numerical differentiation of mode shapes translations using a differentiation/smoothing technique. The methods are applied to a carbon fiber reinforced epoxy rectangular plate, free in space, subjected to two cases of impact damage. It is shown that the method based on curvatures allows the localization of both cases of damage, which can be undetected by visual, X-ray or C-scan inspections. The best localizations are achieved by selecting and applying the method to the most changed mode.Three methods for the damage localization of impact damage in laminated composite plates, based on their vibrational characteristics, are presented in this paper. These methods use double pulse TV holography with acoustic excitation for mode shapes acquisition and the differences in translations, rotations and curvatures. The rotations and curvatures are obtained by numerical differentiation of mode shapes translations using a differentiation/smoothing technique. The methods are applied to a carbon fiber reinforced epoxy rectangular plate, free in space, subjected to two cases of impact damage. It is shown that the method based on curvatures allows the localization of both cases of damage, which can be undetected by visual, X-ray or C-scan inspections. The best localizations are achieved by selecting and applying the method to the most changed mode

Damage localization in laminated composite plates using double pulse-electronic holographic interferometry

One method for the damage localization of impact damage in laminated composite plates, based on their vibrational characteristics, is presented in this paper. This method uses double pulse-electronic holographic interferometry for mode shapes acquisition and the differences in curvatures. The rotations and curvatures are numerically obtained. The method is applied to a carbon fibre reinforced epoxy rectangular plate, free in space, subjected to two cases of impact damage. It is shown that the method based on curvatures allows for the localization of both cases of damage, which can be undetected by visual, X-ray or C-Scan inspections. The best localizations are achieved by selecting and applying the method to the most changed mode

Exponential stability of the wave equation with memory and time delay

We study the asymptotic behaviour of the wave equation with viscoelastic damping in presence of a time-delayed damping. We prove exponential stability if the amplitude of the time delay term is small enough

Two-magnon Raman scattering in insulating cuprates: Modifications of the effective Raman operator

Calculations of Raman scattering intensities in spin 1/2 square-lattice Heisenberg model, using the Fleury-Loudon-Elliott theory, have so far been unable to describe the broad line shape and asymmetry of the two magnon peak found experimentally in the cuprate materials. Even more notably, the polarization selection rules are violated with respect to the Fleury-Loudon-Elliott theory. There is comparable scattering in $B_{1g}$ and $A_{1g}$ geometries, whereas the theory would predict scattering in only $B_{1g}$ geometry. We review various suggestions for this discrepency and suggest that at least part of the problem can be addressed by modifying the effective Raman Hamiltonian, allowing for two-magnon states with arbitrary total momentum. Such an approach based on the Sawatzsky-Lorenzana theory of optical absorption assumes an important role of phonons as momentum sinks. It leaves the low energy physics of the Heisenberg model unchanged but substantially alters the Raman line-shape and selection rules, bringing the results closer to experiments.Comment: 7 pages, 6 figures, revtex. Contains some minor revisions from previous versio

The production of knowledge through religious and social media infrastructure : world making practices among Brazilian Pentecostals

Following Robertson’s discussions on epistemic capital, the article analyses worldmaking procedures being used by members of one of the biggest neo-Pentecostal churches in Brazil – Igreja Universal do Reino de Deus. According to the popular narrative, social media, especially WhatsApp groups, contributed in a crucial way to the spread of sets of conspiracy theories aimed to question “established narratives” and creating an image of Jair Bolsonaro, currently the president of Brazil, as the sole hero (“the messiah” and “the myth”) fighting against the “corrupted” Brazilian state and the “globalist/communist cabal.” The article discusses interactions between members of so-called families created by the Igreja Universal do Reino de Deus. These families could have between a few or around one hundred members, and they are in regular communication (at least a few times per day) through WhatsApp. Most members of one family do not live in walking proximity; therefore, using WhatsApp is often the primary way they interact. The article puts families into a broader context of the media ecosystem owned or influenced by Igreja Universal do Reino de Deus and contextualizes the church as a religious “infrastructure of knowing.” The article discusses sources of legitimization of particular knowledge produced and mediated between families. The article argues that communication in families contributes to the creation of unique epistemic tools crucial in re-creating individual worldviews of members Igreja Universal do Reino de Deus

Tentativas De Suicídio E Suicídios Na Atenção Pré-hospitalar

To characterize suicide attempts and suicides in a city in Northwestern Parana State, attended in the pre-hospital care. Methods: Descriptive, cross-sectional study, performed with pre-hospital care records to 257 victims of suicide and suicide attempt, in the period in 2005 to 2012, through two-dimensional analysis by chi-square. Results: There were 180 attempted suicides and 76 suicides. The age ranged 13-93 years, mean 33.5 ± 15.1 years and most prevalent in young male population. The events concentrated on the months of spring and summer, in the urban area. The use of biting object was the most used method, followed by poisoning and precipitation high places. Conclusion: To know the characteristics, methods and aggravating factors provide subsidies for the implementation of prevention measures. © 2016, Editora Cientifica Nacional Ltda. All rights reserved.65323123

Indirect search for dark matter: prospects for GLAST

Possible indirect detection of neutralino, through its gamma-ray annihilation product, by the forthcoming GLAST satellite from our galactic halo, M31, M87 and the dwarf galaxies Draco and Sagittarius is studied. Gamma-ray fluxes are evaluated for the two representative energy thresholds, 0.1 GeV and 1.0 GeV, at which the spatial resolution of GLAST varies considerably. Apart from dwarfs which are described either by a modified Plummer profile or by a tidally-truncated King profiles, fluxes are compared for halos with central cusps and cores. It is demonstrated that substructures, irrespective of their profiles, enhance the gamma-ray emission only marginally. The expected gamma-ray intensity above 1 GeV at high galactic latitudes is consistent with the residual emission derived from EGRET data if the density profile has a central core and the neutralino mass is less than 50 GeV, whereas for a central cusp only a substantial enhancement would explain the observations. From M31, the flux can be detected above 0.1 GeV and 1.0 GeV by GLAST only if the neutralino mass is below 300 GeV and if the density profile has a central cusp, case in which a significant boost in the gamma-ray emission is produced by the central black hole. For Sagittarius, the flux above 0.1 GeV is detectable by GLAST provided the neutralino mass is below 50 GeV. From M87 and Draco the fluxes are always below the sensitivity limit of GLAST.Comment: 14 Pages, 7 Figures, 3 Tables, version to appear on Physical Review

A bacteriophage detection tool for viability assessment of Salmonella cells

Available online 7 September 2013Salmonellosis, one of the most common food and water-borne diseases, has a major global health and economic impact. Salmonella cells present high infection rates, persistence over inauspicious conditions and the potential to preserve virulence in dormant states when cells are viable but non-culturable (VBNC). These facts are challenging for current detection methods. Culture methods lack the capacity to detect VBNC cells, while biomolecular methods (e.g. DNA- or protein-based) hardly distinguish between dead innocuous cells and their viable lethal counterparts. This work presents and validates a novel bacteriophage (phage)-based microbial detection tool to detect and assess Salmonella viability. Salmonella Enteritidis cells in a VBNC physiological state were evaluated by cell culture, flow-cytometry and epifluorescence microscopy, and further assayed with a biosensor platform. Free PVP-SE1 phages in solution showed the ability to recognize VBNC cells, with no lysis induction, in contrast to the minor recognition of heat-killed cells. This ability was confirmed for immobilized phages on gold surfaces, where the phage detection signal follows the same trend of the concentration of viable plus VBNC cells in the sample. The phage probe was then tested in a magnetoresistive biosensor platform allowing the quantitative detection and discrimination of viable and VBNC cells from dead cells, with high sensitivity. Signals arising from 3 to 4 cells per sensor were recorded. In comparison to a polyclonal antibody that does not distinguish viable from dead cells, the phage selectivity in cell recognition minimizes false-negative and false-positive results often associated with most detection methods

Borboletas (Lepidoptera: Hesperioidea e papilionoidea) de val de serra, região central do rio grande do sul, Brasil

The butterfly fauna of the Atlantic Forest Biome is reasonably well-known up to the southern limit of its distribution. However, there are knowledge gaps nearby the central region of Rio Grande do Sul State, whose forest areas are considered priorities for biological conservation. This study investigated the butterfly assemblage of a riparian fragment in an ecotone area between Mixed Ombrophilous Forest and Seasonal Decidous Forest, in Itaara municipality. From September 2005 to September 2006, after 105 net-hours through active search sampling, 877 butterflies were registered representing 104 species. Three more species were registered posteriorly, increasing total richness to 107. The most abundant species were the Nymphalidae Hermeuptychia hermes (Fabricius, 1775), Yphthimoides celmis (Godart, [1824]), Agraulis vanillae maculosa (Stichel, [1908]), Tegosa claudina (Eschscholtz, 1821) and Vanessa braziliensis (Moore, 1883). One new record for the State and four new ones for the central region were registered besides the southern endemic Papilionidae Euryades corethrus (Boisduval, 1836) and the Lycaenidae Arcas ducalis (Westwood, 1852), considered indicator of Atlantic forest preserved areas. Due to the representativeness of the registered fauna, it is suggested the increase of conservation efforts in the area and stimulation of new ecological studies with the local biodiversity

Evaluation of acute oral toxicity and diuretic activity of Rudgea viburnoides (Cham.) Benth. (congonha-de-bugre)

Rudgea viburnoides é utilizada popularmente como diurética, hipotensora, antirreumática, antissifilítica, depurativa do sangue e tratamento da dispepsia. Este trabalho teve como objetivos avaliar a toxicidade aguda e a atividade diurética do extrato etanólico bruto (EEBFRV) das folhas da R. viburnoides. Na toxicidade aguda empregou-se o teste de Classe, nas doses de 2000 e 5000 mg/kg, dose única, gavage, em camundongos Swiss e ratos Wistar (ambos os sexos). Na atividade diurética administrou-se em ratas Wistar o extrato bruto (40, 80 e 160 mg/kg, furosemida 20 mg/kg (controle +) e solução salina 0,9% (controle -). Não houve letalidade ou sinais de intoxicação, indicando baixa toxicidade desse extrato. O efeito diurético foi dose-dependente nas 24 h, com aumento dos parâmetros: volume de urina 24 h, excreção dos eletrólitos sódio, potássio e cloreto, uréia e creatinina. Os resultados até o momento, podem justificar a sua utilização popular como diurética.Rudgea viburnoides is popularly used as anti-hypertensive, anti-rheumatic, antissifilitic, blood depurative and for treatment of dyspepsia (leaves, bark, tea). The acute toxicity of ethanolic extract (EEBFRV) in single dose was performed by gavage of doses of 2000 and 5000 mg/kg in Swiss mice and Wistar rats, both sexes, by the class test. To diuretic activity in Wistar rats, it was used the EEBFRV at the doses of 40, 80 and 160 mg/kg, furosemide 20 mg/kg (control +), and saline solution 0.9 % (control -). Regarding acute toxicity, no mortality and no toxicity signs at the dose levels were observed, indicating low toxicity of the extract. The EEBFRV showed statistically significant dose-dependent diuretic effect in 24 h, increasing all parameters evaluated (24h urine volume, excretion of Na+, K+ and Cl- electrolytes, urea (BUN) and creatinine). Thus, the results so far may justify the popular use of Rudgea viburnoides as diuretic.Colegio de Farmacéuticos de la Provincia de Buenos Aire