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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).

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.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.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.

The production of Hard X‐rays has become a tricky problem on medium energy storage rings. It requires Insertion Devices (IDs) with high magnetic field and a large number of periods. To cover the 20–50 keV photon energy range at SOLEIL (2.75 GeV), an in‐vacuum wiggler (WSV50) has been preferred to a superconducting ID. The wiggler is composed of 38 periods of 50 mm producing a 2.1 T field at a minimum magnetic gap of 5.5 mm. To minimize the magnetic forces acting between magnet arrays (8.5 tons), a compensation system composed of non magnetic springs has been mounted apart from the magnet system to reduce the mechanical deformations. The wiggler has been assembled step by step by means of a genetic algorithm which minimizes the magnetic errors measured with a flipping coil. This paper presents the mechanical and magnetic design of the wiggler as well as the construction and the magnetic measurements.

Developed under the auspices of UNESCO, SESAME (Synchrotron light for Experimental Science and Application in the Middle East) will be a major international research centre in the Middle East / Mediterranean region. Most of the applications require hard x‐rays up to 20 keV photons. SESAME will be a 2GeV 3rd Generation Ligth Source with an emittance of 17 nmrad and 13 places for the installation of insertion devices with a length around 3 meter. The circumference of the machine will be 120m. As injector the 800 MeV Booster Synchrotron will be used with small changes. Furthermore also the BESSY I quadrupoles and sextupoles can be used. In a later stage these new ones will be replaced in order to increase the length of the straight sections and to introduce mini beta sections for the reduction of the beam cross section. At SESAME around 35 % of the circumference can be used for the installation of insertion devices.

We have collected data on the second follow-up of 27 patients who underwent musculocutaneous flap closure of their ischial pressure sores. Thirty-seven ulcers were operated on between 1988 and 1993 using the V-Y advancement hamstring musculocutaneous island flap. At the initial follow-up (mean = 20 months) in 1993, despite 33% of patients having had recurrent ulcers and 14.8% having undergone re-advancements, only 14% of patients had non-healing ulcers. In 1997, follow-up period ranged from 18 to 90 months, with a mean of 62 months. Four patients were lost to follow-up resulting in 23 patients (n = 23) for the current study. Nine patients were tetraplegic and the remaining 14 were paraplegic. Four of the 23 patients had died at follow-up therefore making the number of living patients 19 (n = 19). The total number of ulcers operated on in the current study was 29 (U = 29). Overall, ulcer and patient recurrence rates were 41.4% and 47.8% respectively. Despite this, 89.5% of patients had intact flaps at the time of follow-up. We recommend the use of the hamstring V-Y musculocutaneous flap as a reliable and safe reconstructive modality in the management of ischial pressure sores and by identifying the group of patients susceptible to ulcer recurrence we have proposed a protocol for their long-term follow-up.

Interest in craniofacial osteodistraction has increased in recent years parallel with the growing attention given to the role of growth factors in tissue healing and regeneration. This study was embarked upon to investigate the expression of bFGF, TGF-β and IGF-1 in the distraction zone of the mandible. Fourteen growing sheep were allocated to three experimental groups. Six animals were allocated to Groups A and B ( n = 12) and underwent bilateral mandibular corticotomies with fixation of an external lengthening device. The distraction protocol consisted of a rate of 1.0 mm/day (twice daily) for 20 days followed by a consolidation phase of 20 days after which the sheep were sacrificed. Group C comprised of age matched sham operated animals ( n = 2). Bone histochemistry for growth factors were performed in the harvested mandibles. A strong staining of bFGF was seen in the osteoblasts, osteocytes and osteoid matrix following 20 days of distraction and 20 days of consolidation compared to the control group. TGF-β and IGF-1 demonstrated mild but clear staining in osteocyte and osteoblast cells and TGF-β stained positively in the osteoid seam in the experimental groups. These finding suggest that bFGF, IGF-1 and TGF-β may play different roles in the remodelling phase of distraction osteogenesis.

A case of recurrent acoustic neuroma in a 58-year-old man is presented. The tumour was initially subtotally removed and then was irradiated using stereotactic radiosurgery. He represented with ataxia and new onset headache four years later and underwent further surgery for recurrence of his acoustic neuroma. The literature is reviewed and the authors' view point on the different modalities of treatment is discussed.