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The injection of urea-water solution (UWS) sprays into engine-close selective catalytic reduction (SCR) systems faces developers with complex challenges regarding two-phase flow and deposit formation. Potential spray impact on the static mixing elements inside the exhaust duct can lead to accumulation of liquid film and solid deposits, which may result in detachment of large UWS droplets at the trailing edges of the mixer blades. Present work focuses on the mechanisms of film and deposit formation within the scope of a joint study on spray preparation in the mixing section of SCR systems. A production type SCR exhaust system is used for optical investigations on gas flow and UWS droplets at the mixing element using Laser Doppler Anemometry (LDA) and Long Distance Microscopy (LDM) with a high-speed camera. Measured shear flows inside the mixing element are up to three times higher than the flow velocity upstream the mixer. Here, a decrease of droplet diameters of detached droplets is revealed with increased shear flow velocity. Characteristic urea deposits are created in a laboratory test bench and their surface structure is measured by use of Confocal Microscopy. Results show highly rough surface structures, which are used as input parameters together with the flow measurements to define the computational domain at the trailing edge of the mixer blades. Smoothed Particle Hydrodynamics (SPH) method is adopted for the numerical simulation of the transient two-phase flow and validated by LDM high-speed recordings of droplet detachment. Comparisons reveal a distinct influence of solid depositions on the re-atomization of the liquid film at the rear edge of the mixer blade. By interface resolving simulations with a phase-field method, the wall impingement of a sequence of large secondary droplets and associated film formation are studied. The results indicate that UWS film formation at the exhaust pipe wall may be reduced by hydrophobic surfaces and high gas velocities near the wall.

Electrocardiography (ECG) is a simple, valuable and easily applicable test that can be used in supporting the diagnosis and assessing the severity of pulmonary thromboembolism (PTE). In this study, it was aimed to identify the role of ECG scoring in diagnosis and follow up of PTE in comparison with community acquired pneumonia (CAP). Patients with the diagnosis of PTE and CAP were included in the study prospectively between January 2007 and January 2009. ECG scorings were evaluated by two different cardiologists by the method described by Daniel et al at admission (day 0) and day 3, 10 and one month of treatment. Median values of ECG scorings were compared between days and between groups. Forty-five patients with PTE, 35 patients with CAP were included in the study. Although no statistically significant difference was identified between the ECG scorings of the two groups in each measurement point, ECG scores decreased more rapidly in PTE group within days. Within the PTE group, day 0 ECG score was identified higher in submassive patients than nonmassive ones (p=0.001). Although ECG score did not differentiate PTE from CAP, depending on its rapid decrease in PTE, it can be used in the follow up. For submassive PTE patients that must be diagnosed and treated immediately, ECG scorings can be used to support the diagnosis and to assess the clinical severity.

Based on simple rate equations for the Rydberg excitation process, we are able to model microscopically the dynamics of Rydberg excitation in ensembles of a large number of ultracold atoms, which is beyond the capabilities of fully ab initioapproaches. Our results for the distribution of Rydberg atom numbers are in good agreement with recent experimental data, confirming the quenching of the distribution caused by Rydberg-Rydberg interactions.

Objective: To demonstrate the epidemiological features, clinical presentation, clinical courses and outcomes in critically ill children with pandemic influenza (H1N1) 2009 in pediatric intensive care units (PICU).Design and setting: Prospective, observational, multi-center study and 13 tertiary PICUs.Patients: 83 children with confirmed infection due to pandemic influenza (H1N1) 2009, detected by RT-PCR between November 1 and December 31, 2009 who required PICU.Results: In two months period, 532 children were hospitalized with pandemic influenza (H1N1) 2009 and 83 (15.6%) of them needed critical care. For the 83 patients requiring critical care, the median age was 42 months. Twenty of these patients (24.1%) had no underlying illness. The PICU admission indications were respiratory distress/respiratory failure in 66 (79.5%), neurologic deterioration in 6 (7.2%) and gastrointestinal symptoms in 5 (6.0%) of the patients. Acute lung injury was diagnosed in 23 (27.7%), acute respiratory distress syndrome in 34 (41%) of the critically ill children and 51 (61.4%) patients needed mechanical ventilation (MV). Oseltamivir was used in 80 (96%) patients. During the study period, overall mortality rate was 13.7%, however, mortality rate was 30.1% (n=25) in children with pandemic influenza A (H1N1) 2009 (p=0.0016) in PICUs. Cause of death was primary H1N1 infection in 16 (64%), nosocomial infection in 4 (16%) and primary disease progression in 5 (20%) patients.Conclusion: Severe disease and high mortality were seen in children with pandemic influenza (H1N1) 2009. Death occurred in all age groups of children with or without underlying illness.