Phospholipid Profiles of Oleaginous Pressed Cakes Using NMR and Gas Chromatography

Camelina, flaxseed, hemp, sesame, and walnut cakes were analyzed for their phospholipid (PL) content and composition using ³¹P and ¹H nuclear magnetic resonance and gas chromatography. The data evidenced variations between the sources in terms of (1) total lipid content and PL concentration, camelina cake being the richest source of PLs, (2) PL composition, phosphatidylcholine being the most abundant phospholipid in sesame and hemp cakes, whereas phosphatidylinositol represented about 25% of the total PLs in most cakes, and (3) fatty acid composition of the PLs, camelina cake being the richest source of omega 3 polyunsaturated fatty acids. These data may be useful to diversify the PL sources available and to provide PL fractions with specific nutritional or functional properties.     

Fluorescence Polarization Immunoassay for Rapid, Accurate and Sensitive Determination of Ochratoxin A in Wheat

A sensitive and accurate fluorescence polarization (FP) immunoassay has been developed for the determination of ochratoxin A (OTA) in naturally contaminated wheat samples. A fluorescein-labeled OTA tracer was synthesized, and its binding response with three monoclonal antibodies was tested. The most sensitive competitive FP immunoassay showed an IC₅₀ value of 0.48 ng/mL with a negligible cross-reactivity for ochratoxin B (1.7 %) and no cross-reactivity with other mycotoxins commonly occurring in wheat. The wheat sample was extracted with acetonitrile/water (60:40, v/v) and purified by a rapid solid-phase extraction procedure using an aminopropyl column prior to the FP immunoassay. The overall time of analysis was less than 20 min. The average recovery from spiked wheat samples (3 to 10 μg/kg) was 87 %, with relative standard deviations generally lower than 6 %. Limits of detection and quantification were 0.8 and 2.0 μg/kg, respectively. The trueness of the method was assessed by using two reference materials for OTA showing good accuracy and precision. A good correlation (r?=?0.995) was observed between OTA contamination of 19 naturally contaminated wheat samples analyzed by both FP immunoassay and high-performance liquid chromatography/immunoaffinity clean-up used as reference method. These results show that the developed FP method is suitable for high-throughput screening, as well as for reliable quantitative determination of OTA in wheat at level far below the EU regulatory limits.     

Epidemiology of sepsis and multiple organ dysfunction syndrome in children

STUDY OBJECTIVES: To determine the cumulated incidence and the density of incidence of systemic inflammatory response syndrome (SIRS), sepsis, severe sepsis, septic shock, and multiple organ dysfunction syndrome (MODS) in critically ill children; to distinguish patients with primary from those with secondary MODS. DESIGN: Prospective cohort study. SETTING: Pediatric ICU of a university hospital. PATIENTS: One thousand fifty-eight consecutive hospital admissions. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: SIRS occurred in 82% (n=869) of hospital admissions, 23% (n=245) had sepsis, 4% (n=46) had severe sepsis, 2% (n=25) had septic shock; 16% (n=168) had primary MODS and 2% (n=23) had secondary MODS; 6% (n=68) of the study population died. The pediatric risk of mortality (PRISM) scores on the first day of admission to pediatric ICU were as follows: 3.9 +/- 3.6 (no SIRS), 7.0 +/- 7.0 (SIRS), 9.5 +/- 8.3 (sepsis), 8.8 +/- 7.8 (severe sepsis), 21.8 +/- 15.8 (septic shock); differences among groups (p=0.0001), all orthogonal comparisons, were significant (p<0.05), except for patients with severe sepsis. The observed mortality for the whole study population was also different according to the underlying diagnostic category (p=0.0001; p<0.05 for patients with SIRS and those with septic shock, compared with all groups). Among, patients with MODS, the difference in mortality between groups did not reach significance (p=0.057). Children with secondary MODS had a longer duration of organ dysfunction (p<0.0001), a longer stay in pediatric ICU after MODS diagnosis (p<0.0001), and a higher risk of mortality (odds ratio, 6.5 [2.7 to 15.9], p<0.0001) than patients with primary MODS. CONCLUSIONS: SIRS and sepsis occur frequently in critically ill children. The presence of SIRS, sepsis, or septic shock is associated with a distinct risk of mortality among critically ill children admitted to the pediatric ICU; more data are needed concerning children with MODS. Secondary MODS is much less common than primary MODS, but it is associated with an increased morbidity and mortality; we speculate that distinct pathophysiologic mechanisms are involved in these two conditions.     

Experimental study of convective heat transfer on a finned rotating cylinder

In this study, the local convective heat transfer from a rotating finned cylinder to the surrounding air was evaluated using an infrared thermographic experimental set up. Solving the inverse conduction heat transfer problem allows the local convective heat transfer coefficient to be identified. We used the specification function method, along with spatio-temporal regularization, to develop a model of local convective heat transfer in order to take lateral conduction and 2D geometry into account. This model was tested using rotational Reynolds numbers (based on the cylinder diameter and the peripheral speed) between 4300 and 17 900. The local heat transfer on the fin surface was analyzed to determine the influence of the rotational Reynolds number and the influence of the height and spacing of the fins. In this paper, we propose an efficiency definition that allows the optimal geometrical configuration of the finned cylinder to be identified for the given operating conditions.     

Development of a mapping approach encompassing most fluvial processes: Lessons learned from the freedom space for rivers concept in Quebec (Canada)

The consensus around the need for a shift in river management approaches to include more natural processes is steadily growing amongst scientists, practitioners, and governmental agencies. The freedom space for rivers concept promotes the delineation of a single space that integrates multiple fluvial dynamics such as floods, lateral migration, channel avulsions, and riparian wetlands connectivity. The objective of this research is to assess the validity of the hydrogeomorphological approach to delineate the freedom space for an extensive sampling of river reaches, covering 167 km, in contrasting watersheds in Quebec (Canada). Comparative analysis was conducted on the relative importance of erosion and flood processes on the freedom space delineation for various fluvial types. Semiautomated tools based on light detection and ranging (LiDAR) digital elevation models were also tested on an additional 274 km of watercourses to facilitate freedom space mapping over extensive zones and for highly dynamics environments such as alluvial fans. In the studied reaches, flood and erosion processes occur respectively, on average, in a space equivalent to 2.6 and 20.6 channel widths. In unconfined landscapes, flood processes represent an area up to almost four times the area of erosion processes expected in a 50‐year period. In partly confined and confined environments, erosion processes are more likely to exceed flooding zone, and therefore need to be integrated in the mapping. This study helps better determine the conditions for which the full methodology of freedom space mapping is required or where semiautomated methods can be used. It provides useful guidelines for the implementation of the freedom space approach.     

Generalized-α scheme in the PFEM for velocity-pressure and displacement-pressure formulations of the incompressible Navier–Stokes equations

Despite the increasing use of the particle finite element method (PFEM) in fluid flow simulation and the outstanding success of the Generalized-$\alpha$ (GA) time integration method, very little discussion has been devoted to their combined performance. This work aims to contribute in this regard by addressing three main aspects. First, it includes a detailed implementation analysis of the GA method in PFEM. The work recognizes and compares different implementation approaches from the literature, which differ mainly in the terms that are $\alpha$-interpolated (state variables or forces of momentum equation) and the type of treatment for the pressure in the time integration scheme. Second, the work compares the performance of the GA method against the Backward Euler and Newmark schemes for the solution of the incompressible Navier–Stokes equations. Third, the study is enriched by considering not only the classical velocity-pressure formulation but also the displacement-pressure formulation that is gaining interest in the fluid-structure interaction field. The work is carried out using various 2D and 3D benchmark problems such as the fluid sloshing, the solitary wave propagation, the flow around a cylinder, and the collapse of a cylindrical water column.