2,064 research outputs found

    STR-837: PUNCHING SHEAR BEHAVIOUR OF HIGH STRENGTH CONCRETE SLAB-COLUMN CONNECTIONS REINFORCED WITH GFRP BARS

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    The catastrophic nature of punching shear failure exhibited by flat plate system requires a great attention and robust predictions of the behaviour of slab-column connections. This paper presents an experimental study carried out to investigate the punching shear behaviour of fibre-reinforced polymer (FRP) reinforced concrete (RC) interior slab-column connections made of high strength concrete (HSC). Three full-scale HSC specimens were constructed and tested up to failure. The three connections were reinforced with GFRP sand-coated bars with reinforcement ratios of 1.0, 1.5 and 2.0% without any shear reinforcement. The typical dimensions of the test specimens were 2800 × 2800 × 200 mm with a 300 mm square column extending 1000 mm above and below the slab, representing the region of negative bending moment around an interior supporting column of a parking structure. All specimens were simply-supported along all four edges with the corners free to lift. The connections were subjected to vertical load and unbalanced moment that were monotonically applied through the column tips. The behaviour of the specimens in terms of the deformation and strength characteristics is discussed. Increasing the reinforcement ratio increased the punching shear capacity and decreased the reinforcement strains and deflections at the same load level. The test results were also compared to the predictions of the relevant North American codes where applicable

    The Black Seed Nigella sativa Linnaeus - A Mine for Multi Cures: A Plea for Urgent Clinical Evaluation of its Volatile Oil

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    AbstractThis review almost covers what is actually known to date about the black seed and its constituents. It is clear that most of the potent and fruitful activity resides in its volatile oil and a protein component. However, the volatile oil suffers the drawback of the bronhoconstricting effect of thymoquinone. However, the latter can be easily removed from the oil to obtain a dethymoquinoneated oil that has already been shown to possess the major characteristics of the whole oil. At this moment there are a lot of experimental data that hopefully, may stimulate the beginning of the era of pilot clinical studies to evaluate the clinical potential of the volatile oil, some of the protein fractions and the dethymoquinoneated volatile oil. It is hoped that this plea will have a rapid response

    Interaction of 160 GeV- Muon with Emulsion Nuclei

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    In this work we present some results of the interaction of high energy muons with emulsion nuclei. The interaction results in emission of a number of fragments as a consequence of electromagnetic dissociation of the excited target nuclei. This excitation is attributed to absorption of photons by the target nuclei due to the intense electric field of the very fast incident muon particles. The interactions take place at impact parameters that allows ultra-peripheral collisions to take place, leading to giant resonances and hence multi-fragmentation of emulsion targets. Charge identification, range, energy spectra, angular distribution and topological cross-section of the produced fragments are measured and evaluatedComment: 13 pages, 4 figures, 4 tables. Accepted for publication in IJMP

    Magnetogravitational Vortex-Sheet Instability of Two Superposed Conducting Fluids in Porous Medium Under Strong Magnetic Field

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    The instability of two superposed homogeneous streaming uids is discussed under gravitational force and uniform magnetic eld in porous medium. The two streams are moving in opposite directions with equal velocities parallel to the horizontal plane. The solution has been obtained through the normal mode technique, and the most gen- eral dispersion relation has been obtained as 20th-order equation for the growth rate with quite complicated coe¢ cients. Solving numeri- caly the dispersion relation for appropriate boundary conditions with high Alfvén and sound velocities, it is found that uid velocities and porosity of porous medium have stabilizing e¤ects, and Alfvén and sound velocities have destabilizing e¤ects, while medium permeabil- ity has a slightly stabilizing e¤ect, and the dynamic viscosities have slightly destabilizing e¤ect. The limiting cases of non-porous medium have also been studied for both streaming and stationary uids.Key words: Hydrodynamic stability; Conducting uids; Flows through porous media; Gravitational force; Magnetohydrodynamic

    Evaluation of transvaginal ultrasound role in the prediction of adenomyosis: correlation with histopathology

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    Background: Adenomyosis is a common gynecologic disorder that primarily affects women of reproductive age that has reported incidence of 5-70% in surgical and postmortem specimens. The aim of this study was to evaluate the accuracy of various transvaginal sonographic findings in adenomyosis by comparing them with histopathological results and to determine the most valuable sonographic feature in the diagnosis of adenomyosis.Methods: All transvaginal US findings were correlated with those from histologic examination. The frequency of presenting symptoms and signs of adenomyosis were evaluated. Transvaginal US depicted 10 of 12 pathologically proved cases of adenomyosis. Adenomyosis was correctly ruled out in 33 of 38 patients.Results: Transvaginal US had a sensitivity of 83%, a specificity of 86%, and a positive and negative predictive value of 66% and 94%, respectively. Of the 10 patients with true-positive findings at transvaginal US, the myometrium demonstrated heterogeneous with or without the presence of cysts in nine (75%) patients, linear striation in four (33.3%) patients and globular uterus in six (50%) patients. Three (25%) of 12 cases of adenomyosis had an enlarged uterus, adenomyosis was a significant association with high parity.Conclusions: Adenomyosis can be diagnosed with a considerable accuracy by transvaginal ultrasound. The most common sonographic criteria of adenomyosis are heterogeneous myometrial appearance while the most specific criteria are myometrial cysts, sub-endometrial echogenic linear striations and globular configuration of the uterus
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