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Measurements on the strong-field ionization of carbonyl sulfide molecules by short, intense, 2~\um wavelength laser pulses are presented from experiments where angle-resolved photoelectron distributions were recorded with a high-energy velocity map imaging spectrometer, designed to reach a maximum kinetic energy of 500~eV. The laser-field-free elastic-scattering cross section of carbonyl sulfide was extracted from the measurements and is found in good agreement with previous experiments, performed using conventional electron diffraction. By comparing our measurements to the results of calculations, based on the quantitative rescattering theory (QRS), the bond lengths and molecular geometry were extracted from the experimental differential cross sections to a precision better than $\pm5$~pm and in agreement with the known values.

Single particle detection by ultrasound scattering is demonstrated. Polystyrene particles with a diameter of 40 $\mu \text{m}$ are individually counted using a visual spectrogram method. As an alternative a less computationally expensive algorithm for the data analysis using Hilbert transform is also demonstrated. Experiments demonstrating the particle counting capabilities of the sensor for different flow rates and concentrations are shown and linear relationships are observed as expected. The sensor differs from other particle counters by handling high flow–rates (>800 L h−1) and having an extremely low detection limit of about 0.5 particles per mL in 1s, which is orders of magnitudes better than the ones for analogues optical particle sensors.

A new highly sensitive ultrasonic sensor for the detection of particles in fluids is presented. The design differentiates from other methods by working on any fluid as the signal to detect is pressure waves, which allows for detection in optically opaque materials, such as oil, blood, and so on. The sensor is essentially maintenance free, and the low power consumption enables battery powered designs. The sensor provides true online measurements with a total measurement time well below 1 s. The detection limit as a function of particle size was investigated both theoretically and experimentally for polystyrene and silicon dioxide particles, and an excellent agreement was observed. An experimental detection limit that approaches 1 particle per mL for particle diameters above 20 $\mu \text{m}$ is observed. In comparison, the output of the ultrasonic sensor scales with optical turbidity for particles with a specific size. However, this scaling relation is different for different particle sizes, and for this reason, there is no universal relationship between the output of the ultrasonic sensor and optical turbidity.

Strong-field ionization of carbonyl sulphide (OCS) molecules, induced by a linearly polarized mid-infrared (mid-IR) probe laser pulse is investigated experimentally and theoretically. We focus on the dependence of the single-ionization yield on the alignment of the molecular axis with respect to the probe pulse polarization axis. In the experiment, the OCS molecules are 1-dimensionally adiabatically aligned and ionized by a 12-femtosecond pulse centered at 1850 nm. The alignment-dependent ionization yields are compared to the theory based on the two-step model for strong-field ionization. Overall the measurements are consistent with the theoretical results.

The gas-phase structures of four difluoroiodobenzene and two dihydroxybromobenzene isomers were identified by correlating the emission angles of atomic fragment ions created, following femtosecond laser-induced Coulomb explosion. The structural determinations were facilitated by confining the most polarizable axis of each molecule to the detection plane prior to the Coulomb explosion event using one-dimensional laser-induced adiabatic alignment. For a molecular target consisting of two difluoroiodobenzene isomers, each constituent structure could additionally be singled out and distinguished.

Introduction Not sedating critically ill patients reduces the time patients receive mechanical ventilation, decreases the time in the intensive care department and reduces the total hospital length of stay. We hypothesized that no sedation improves hemodynamic stability, decreases the need for vasoactive drugs, diminishes the need for extra fluids and lowers the risk of acute kidney injury. Methods We performed an evaluation on the database from our previous trial of 140 patients randomized to either no sedation vs. sedation with a daily interruption of sedatives. A total of 113 patients were included in the previous statistical analysis. Ten patients had pre-existing renal impairments and were excluded. Data were collected from observational cards and blood samples. Results A total of 103 patients were included in this retrospective review. We registered an increased urine output in the group receiving no sedation compared to the sedated control group (1.15 ml/kg/hour (0.59 to 1.53) vs. 0.88 ml/kg/hour (0.052 to 1.26), P = 0.03). In addition we saw a decrease in the number of patients with renal impairment according to the RIFLE classification (indicating Risk of renal dysfunction; Injury to the kidney; Failure of kidney function, Loss of kidney function and End-stage kidney disease) in the group receiving no sedation compared to the sedated control group (25 (51%) vs. 41 (76%), P = 0.012). The difference in the two groups with respect to mean arterial blood pressure, fluid balance and use of vasoactive drugs was not significant. Conclusions A no sedation strategy to patients undergoing mechanical ventilation increases the urine output and decreases the number of patients with renal impairments. Trial registration ClinicalTrials.gov registration number NCT00466492.