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Lateral intakes are hydraulic structures used for domestic, agricultural and industrial water conveyance, characterized by a very complex three-dimensional morphodynamic behavior: since streamlines near the lateral intake are deflected, some vortices form, pressure gradient, shear and centrifugal forces at the intake generate flow separation and a secondary movement, responsible for local scour and sediment deposition. On the other side, the modeling of flows, besides the sediment transport, in curved channels implies some more complications in comparison with straight channels. In this research, this complex process has been investigated experimentally and numerically, with the mechanism of sediment transport, bed topography evolution, flow pattern and their interactions. Experiments were performed in the Laboratory of Tarbiat Modares University, Iran, where a U-shaped channel with a lateral intake was installed and dry sediment was injected at constant rate into a steady flow. Due to the spiral flow, the bed topography changes significantly and the bed forms in turn affect the sediment entering the intake. Different from the previous works on this topic which were mainly based on laboratory experiments, here, Computational Fluid Dynamics (CFD) numerical simulations with FLUENT software were also performed, specifically with the two-phase Eulerian Model (EM) and Discrete Phase Model (DPM), at the aim of evaluating their performance in reproducing the observed physical processes. This software is used for a large variety of CFD problems, but not much for simulating sediment transport phenomena and bed topography evolution. The comparison of the results obtained through the two models against the laboratory experimental data proved a good performance of both the models in reproducing the main features of the flow, for example, the longitudinal and vertical streamlines and the mechanism of particles movement. However, the EM reveals a better performance than DPM in the prediction of the secondary flows and, consequently, of the bed topography evolution, whereas the DPM well depicts the particles pattern, predicts the location of trapped particles and determines the percentage of sediment entering the intake. The numerical models so calibrated and validated were applied to other cases with different positions of the intake in the bend. The results show that mechanism of sediment entrance into the intake varies in different position. If the intake is installed in the second half of the bend, the sediment accumulates along the inner bank of the bend and enters the intake from downstream edge of intake; on the other side, if it is placed in the first half of the bend, the sediment accumulates along both the inner and the outer bends and, therefore, more sediment enters the intake. Also the results of the simulations performed with the DPM model for different positions of the lateral intake show that for all discharge ratios, the position of 120∘ is the one which guarantees the minimum ratio of sediment diverted to the intake (Gr). [ABSTRACT FROM AUTHOR]

Laser-plasma accelerators (LPA) deliver relativistic electron beams with high peak current and low emittance, with energies up to the GeV-level in only few centimetres. However, the divergence and the energy spread of these beams remain too large for potential light source applications. A magnetic transfer line can be used to manipulate the electron beam phase-space and select the transmitted energies with a slit located at its center. We will show that with a proper focusing optics along the line, one can tune the energy spread of the beam at a given energy without loss and produce undulator radiation with controlled bandwidth. We present analytic studies, numerical simulations and experimental results on the controled electron beam transport and application to undulator radiation with a control of the bandwidth. [ABSTRACT FROM AUTHOR]

Background:Novel substances often referred to as “designer drugs” have emerged as drugs of abuse, and recognition of these is difficult as routine blood and urine screening tests do not detect these agents. U-47700 is a synthetic selective μ-opioid agonist that can be bought online for as little as $40 per gram. We report two patients presenting after insufflation of U-47700, with subsequent confirmation of this substance in urine samples. Case details:A 26-year-old man and 24-year-old woman insufflated a substance they believed to be “synthetic cocaine.” The man was found down with cyanosis and agonal respirations. He was intubated and taken to hospital where he recovered well with supportive care. The woman presented with anxiety, tremors and drowsiness and was admitted for observation. Urine samples from both patients were analyzed using GC/MS/MS and LC/QToF, and U-47700 was isolated in both cases. No other opioids were detected. Discussion:These cases are concerning because U-47700 is a relatively new agent that is easy to obtain over the internet and has the potential to cause significant morbidity and mortality. [ABSTRACT FROM PUBLISHER]

More than 50 years after the laser discovery, X-ray free electron lasers (FEL), the first powerful tuneable, short pulse lasers in the X-ray spectral range, are now blooming in the world, enabling new discoveries on the ultra-fast dynamics of excited systems and imaging. LUNEX5 demonstrator project aims at investigating paths towards advanced and compact FELs. Two strategies are adopted. The first one concerns the FEL line where seeding and echo harmonic generation are implemented together with compact cryogenic in-vacuum undulators. In the second one, the electron beam is no longer provided by a conventional linear accelerator but by a laser plasma process, while a necessary particular electron beam manipulation is required to handle the electron properties to enable FEL amplification. [ABSTRACT FROM AUTHOR]

Despite huge environmental, economical, health, and societal costs of pesticides, research has argued that farmers in developing countries will continue to use pesticides. The present study used an extended model of the theory of planned behavior (TPB), which includes the additional variables of moral norm and self-identity, to predict the farmers’ decisions (intentions) regarding pesticides usage in a multistage, clustered random sample of farmers (n= 150) in a face-to- face survey of students that was undertaken in Dyer County in Southern Iran. The reliability and validity of the instruments were examined and approved. Findings revealed that the extended model is an improvement over the standard TPB variables for predicting intention. Hierarchical regression analysis showed that attitude, subjective norm, perceived behavior control and self-identity can predict 63% of variances in farmers’ intentions. In conclusion, the results of this study demonstrated that the extended TPB can be used as a conceptual framework for intervention programs aimed at decreasing pesticides spraying intention. [ABSTRACT FROM AUTHOR]

The purpose of this paper is determination of appropriate location of the one submerged vane with respect to the downstream and upstream edge of the lateral intake in a U shape channel bend and choice the best angle of vane for reduce the sediment entry to the lateral intake. In this order we use the Fluent software to numerical simulation of 3D flow pattern around the one vane that locating in front of downstream edge of a lateral intake in a U shape channel bend. The results of numerical were verified with the existing experimental data. Comparison of the predicted x velocity and y velocity field with laboratory measurements indicates that the model capture experimental trend with reasonable accuracy. Computations are performed using Reynolds Stress Model. After model verification, the effect of different position of the vane with respect to downstream of intake (the first, middle and end point of vane is in front of downstream edge of intake) and upstream edge of intake (the first, middle and end point of vane is in front of upstream edge) and effect of different angle of vane (15, 17, 20, 25, 30 degree) on flow pattern and shear stress pattern of bed is considered. The appropriate position and angle of the vane has been selected by effect of the vane on area of high shear stress zone and area of low velocity contour around the vane and reduction of dimension of saddle point near the downstream edge of lateral intake and situation of stream line around the vane and in front of the intake at the bottom of the channel. The results show the best position of vane with respect to downstream edge of lateral intake is the case that the first point of vane is in front of downstream edge of intake and the best position of vane with respect to upstream edge of intake is the case that the end point of vane is in front of upstream edge of intake. Also the results show that the appropriate value for angle of attack of the vane at downstream edge of intake (the first point of vane is in front of downstream edge of intake) is about 20-25 degree and optimum value for angle of attack of the vane at upstream edge of intake (the end point of vane is in front of upstream edge of intake) is about 17-20 degree. [ABSTRACT FROM AUTHOR]

Background and aims: Extra Corporeal Shockwave Lithotripsy (ESWL) is the treatment of choice for urinary lithiasis. Majority of patients experienced pain during ESWL. Acupuncture is a traditional method of treatment in which relieving pain is a feature. This study aimed to evaluate its therapeutic effect on diminishing the pain during ESWL. Method: This clinical trial study performed on 100 patients infected to Urinary lithiasis who were candidate to ESWL operation. They were visited by Acupuncture specialist before starting ESWL and randomly divided into two groups of True Acupuncture and Sham acupuncture. In the first group, acupuncture was carried out in 4 special points of acupuncture for 30 minutes and in the second group acupuncture was ineffectively applied to the same points for 30 minutes. Then ESWL was begun and the intensity of pain compared in two groups using the numeric 0-10 VAS scale. Results: Findings in this study showed that the pain rate mean was significantly lower in true acupuncture group (2.74 ±0.92) than Sham group (4.34 ±0.87). Also, stone size in both groups was significantly related to pain intensity during ESWL (P<0.01). As the stone is bigger, the pain will be more. Age and sex did not have any significant effect on pain. Conclusion: Applying acupuncture in patients, who have been under ESWL, reduces the pain during ESWL. [ABSTRACT FROM AUTHOR]