Diverting river flow during construction of a main dam involves the construction of cofferdams, and tunnels, channels or other temporary passages. Diversion channels are commonly used in wide valleys where the high flow makes tunnels or culverts uneconomic. The diversion works must form part of the overall project design since it will have a major impact on its cost, as well as on the design, construction program and overall cost of the permanent works. Construction costs contain of excavation, lining of the channel, and construction of upstream and downstream cofferdams. The optimization model was applied to obtain optimalchannel cross section, height of upstream cofferdam, and height of downstream cofferdamwith minimum construction costs for diversion works which is solved by PSO method using MATLAB. The optimization model was applied to prepare the optimal design graphs.It can be noticed, at any design flowrate, optimalwater flow depth, bed width, and height of upstream and downstream cofferdams decrease with increase of the side-slope. Also, it can be observed, at any design flowrate, the construction cost increases with increase of the side-slope.
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In hemodialysis patients, pain associated with needle insertion into an arteriovenous fistula is a physical and psychological problem. The aim of this study was to assess the effectiveness of pre‐puncture application of an ice pack, EMLA cream, or lidocaine spray to reduce pain associated with access puncture.
This was a multicenter study done in nine hemodialysis centers in Iraq. The study utilized a randomized, parallel‐group design, in which patients being dialyzed using an arteriovenous access were allocated into one of four groups. Access puncture was preceded by nothing (contr
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One of the most important virulence factors in Pseudomonas aeruginosa is biofilm formation, as it works as a barrier for entering antibiotics into the bacterial cell. Different environmental and nutritional conditions were used to optimize biofilm formation using microtitre plate assay by P. aeruginosa. The low nutrient level of the medium represented by tryptic soy broth (TSB) was better in biofilm formation than the high nutrient level of the medium with Luria Broth (LB). The optimized condition for biofilm production at room temperature (25 °C) is better than at host temperature (37 °C). Moreover, the staining with 0.1% crystal violet and reading the biofilm with wavelength 360 are considered essential factors in
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This study is concerned with the estimation of constant and time-varying parameters in non-linear ordinary differential equations, which do not have analytical solutions. The estimation is done in a multi-stage method where constant and time-varying parameters are estimated in a straight sequential way from several stages. In the first stage, the model of the differential equations is converted to a regression model that includes the state variables with their derivatives and then the estimation of the state variables and their derivatives in a penalized splines method and compensating the estimations in the regression model. In the second stage, the pseudo- least squares method was used to es
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