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Background: Platelet increment is reportedly lower for maximum stored platelet concentrates (PCs) and during pyrexia, and in vitro function differs between fresh and stored PCs. However, little is known about the function of fresh and stored platelets during inflammation. Objectives: The aim was to study differences in hemostatic function after transfusion of fresh or stored PCs in a human model of experimental endotoxemia. Methods: Thirty-six healthy male subjects received either 2 ng/kg lipopolysaccharide (LPS) or a control (physiological saline 0.9%) and were randomly assigned to subsequently receive an autologous transfusion of either fresh (2-days-old) or stored (7-days-old) platelets, or saline control. Extracellular vesicles (EVs) were determined using flow cytometry, thrombin–antithrombin complex (TATc) was assessed using enzyme-linked immunosorbent assay, and hemostatic function was assessed using rotational thromboelastometry (ROTEM). Results: LPS infusion caused a marked increase in TATc, EVs and fibrinolysis. Thromboelastometry data revealed that following infusion of LPS, subjects exhibited in general a hypocoagulable state compared with those not receiving LPS. Platelet transfusions led to a reduced clotting time and an augmentation in clot strength, indicated by maximum clot firmness, solely among subjects undergoing endotoxemia. There were no significant differences in TATc or amount of EVs release after transfusion of fresh or stored platelets. Conclusion: A significant increase in TATc and EVs as well as a difference in hemostatic function after endotoxemia were observed. During endotoxemia, platelet transfusion resulted in enhanced coagulation and hemostatic function; however, no substantial differences were observed between transfusion of fresh or stored PCs.

A parametric set of velocity distributions has been investigated using a flat-plate experiment. Three different diffusion factors and peak velocity locations were tested. These were designed to mimic the suction surfaces of low pressure (LP) turbine blades. Unsteady wakes, inherent in real turbomachinery flows, were generated using a moving bar mechanism. A turbulence grid generated a freestream turbulence level that is believed to be typical of LP turbines. Measurements were taken across a Reynolds number range 50,000-220,000 at three reduced frequencies (0.314, 0.628, and 0.942). Boundary. layer traverses were performed at the nominal trailing edge using a laser Doppler anemometry system and hot films were used to examine the boundary layer behavior along the surface. For every, velocity distribution tested, the boundary layer separated in the diffusing flow downstream of the peak velocity. The loss production is dominated by the mixing in the reattachment process, mixing in the turbulent boundary layer downstream of reattachment, and the effects of the unsteady interaction between the wakes and the boundary layer. A sensitive balance governs the optimal location of peak velocity on the surface. Moving the velocity peak forward on the blade was found to be increasingly beneficial when bubble-generated losses are high, i.e. at low Reynolds number, at low reduced frequency, and at high diffusion factors. [DOI: 10.1115/1.3192149]

Further evidence on the similarities between transition and separation phenomena occurring in turbomachinery and wind tunnel flows is provided by measurements on a large scale flat plate under a strong adverse pressure gradient. The flat plate has a long laminar separation bubble and is subjected to a range of disturbances with triggering caused by injection of a transverse jet and subsequently by wakes generated by rods moving transversely upstream of the leading edge. Wakes were originally presented individually. Each individual wake provoked a vigorous turbulent patch, resulting in the instantaneous collapse of the separation bubble. This was followed by a very strong, and stable, calmed region. Following the lead given by the experiments of Gutmark and Blackwelder (1987, 'On the Structure of Turbulent Spot in a Heated Laminar Boundary Layer,' Exp. Fluids, 5, pp. 207-229.) on triggered turbulent spots, wakes were then presented in pairs at different wake spacing intervals. In this way wake interaction effects could be investigated in more detail As in the work on triggered turbulent spots the spacing between impinging wakes was systematically varied; it was found that for close wake spacings the calmed region acted to suppress the turbulence in the following turbulent patch. To investigate whether this phenomenon was a recurring one or whether the flow then reverted back to its unperturbed state, the experiments were repeated with three and four rods instead of two. This has the potential for making available a wide range of variables including direction and speed of rod rotation. It was found that the subsequent wakes were also suppressed by the calming effect. It may be anticipated that this repeating situation is present in a turbomachine, resulting in hidden benefits for blade count and efficiency. There may also conceivably be blade loading advantages while retaining favorable heat transfer conditions in high pressure turbines or stall margin in axial compressors. The inherent and prospective benefits of the calming effect therefore need to be understood thoroughly and new opportunities exploited where this is feasible. a [DOI: 10.1115/1.2950054]

A finite element model that calculates the energy dissipation to be expected in a crack during sonic infrared (SIR) imaging is described. The finite element model calculations presented, verify the experimental conclusion that chaotic sound excitation produces more heating in cracks than does nonchaotic sound at comparable sound excitation power levels.

Laminar separation and transition phenomena were investigated experimentally in the wake-disturbed flow over a 2.4 m long flat plate. A controlled diffusion pressure distribution, representative of that on a compressor blade, was imposed but with sufficiently strong loading to cause laminar separation. Boundary layer velocity traverses were performed at several longitudinal stations. Wakes were generated upstream by a single rod, parallel to the leading edge, attached to a rotating disk mounted flush in the sidewall of the working section. Data are presented in the form of velocity traces and contours of velocity and turbulent intermittency. The results highlight the interaction between the incoming wake and the natural boundary layer which features a long and thin laminar separation bubble; they demonstrate that wind tunnel experiments provide a good representation of boundary layer behavior under wake disturbances on turbomachinery blading. The calmed region behind the disturbance is a feature that is even stronger behind a wake interaction than behind a triggered turbulent spot. Intermittency values for the undisturbed flow in the separation bubble reattachment region are well represented by Narasimha's universal intermittency distribution, lending support to the use of intermittency-based predictive routines in calculations of blade boundary layers. [DOI: 10.1115/1.1829729]

Byline: R. E. Villavicencio (1), T. J. Forbes (1), R. L. Thomas (2), R. A. Humes (1) Keywords: Pressure recovery; Aortic valve stenosis; Pediatrics Abstract: This study was designed to evaluate the phenomenon of pressure recovery in pediatric patients with aortic stenosis and also to evaluate how observed differences between catheter and Doppler gradients can be predicted by Doppler echocardiography. Doppler measurements of aortic valve stenosis gradients are known to overestimate observed gradients in the catheterization laboratory. Pressure recovery has been shown to be a contributing factor to this discrepancy. However, the clinical relevance of correcting Doppler gradients using the pressure recovery equation has not been evaluated in the pediatric population. Simultaneously obtained catheter and Doppler gradients were studied in 14 patients (range, 0.03--18 years mean, 4.1 years) with aortic valve stenosis. A total of 23 data points were measured because 9 patients underwent balloon valvuloplasty and had both a pre- and a post-balloon valvuloplasty data point in the study. The catheter gradients were then compared to peak, mean, and pressure recovery corrected Doppler gradients. Pressure recovery was calculated using a previously validated equation. As expected, measured echocardiographic continuous-wave peak Doppler gradients overestimated the observed catheter gradients (range, 16--93 mmHg mean, 43 mmHg). The continuous-wave peak Doppler gradients, mean, and pressure recovery adjusted gradients were equally as good in correlating the observed catheter gradients to those obtained by Doppler echocardiography (r = 0.92). However, pressure recovery corrected Doppler gradients were in better agreement with catheter gradients than echocardiographic mean or peak Doppler gradients (95% limit of agreement: -9 to 19 mmHg for pressure recovery corrected gradients, -30 to 11 mmHg for mean Doppler gradients, and 2--83 mmHg for peak Doppler gradients). Measured continuous-wave peak Doppler gradients consistently overestimated catheter gradients. The noted differences may be predicted using the pressure recovery equation. Pressure recovery is a significant factor in children with aortic valve stenosis. Author Affiliation: (1) Department of Pediatrics, Division of Cardiology, Wayne State University School of Medicine/Detroit Medical Center and Children's Hospital of Michigan, 3901 Beaubien Avenue, Detroit, MI 48201, USA (2) Department of Pediatrics, Children's Research Center of Michigan, Detroit, MI 48201, USA Article History: Registration Date: 01/01/2002 Online Date: 30/04/2003

Research is presented concerning the enzymatic treatment of soy flour which had been defatted by commercial pectinases. The use of a stainless steel ultrafiltration membrane system for diafiltration is discussed.

Thermal wave reflections from a plane boundary were studied.

The plastic yield and fracture of rubber-modified polystyrene specimens under tensile load have been investigated at room temperature. The experimental procedure consisted of rapidly alternating measurements of transmitted and emitted infrared (IR) radiation from samples under tensile stress. The load-displacement data were simultaneously recorded. Both single-edge-notched and dog-bone-shaped test coupons were studied. In each tensile test run, we observed a significant decrease of material transparency in the IR which occurred near the low yield point. A further increase in material deformation was accompanied by a substantial temperature increase. After material failure, the surface morphology of the test specimens in the vicinity of the crack was examined using atomic force microscopy (AFM). Our results are explained in the context of existing models of material crazing., The toughening properties of rubber added to a glassy polymer in form of small particles, and the ability of such two-component systems to endure large strains, have long been established [...]

Previous work on phenotypic plasticity in hatchling reptiles has dealt almost exclusively with lizards and turtles from temperate zone habitats, in taxa where the only maternal control over incubation regimes is exerted via nest site selection. In contrast, water pythons (Liasis fuscus) in northern Australia are tropical snakes that show facultative maternal brooding, with shivering thermogenesis to warm the clutch. Thus, incubation temperatures of this species are influenced both by nest site selection and by maternal care. We experimentally simulated three thermal regimes typical of different types of natural nests in our study population. These were (1) hot, stable temperatures typical of nests laid in the burrows of varanid lizards (constant 32 ° C); (2) lower and more variable temperatures typical of nests laid inside tree root boles, either with maternal attendance (diel range 27.1 °32.9 ° C); or (3) in root boles but without maternal attendance (24.3 °-32.9 ° C). We incubated 187 eggs from 15 clutches obtained from field-caught gravid pythons, using a split-clutch design to quantify influences on morphology (offspring size and shape), locomotor performance (swimming ability), and behavior (escape tactics, propensity to strike, willingness to feed in captivity). The thermal regime during incubation strongly affected incubation periods, body sizes, body shapes (mass and tail length relative to snout-vent length), initial growth rates, escape behavior, and willingness to feed. We also detected strong maternal effects on all of these traits, and interactions between maternal effects and incubation regimes. Thus, a female python's 'decisions' as to where she lays her eggs and whether she remains and broods them through development have major consequences for the phenotypes of her offspring. Key words: endothermy; hatchlings; nest site; parental care; phenotypic plasticity; python; Liasis fuscus; thermogenesis; tropics., INTRODUCTION A central assumption of many Darwinian analyses is the notion that phenotypic variation has an underlying genetic basis, and hence that natural selection on phenotypes has the potential to [...]

The experimental thermal wave images of planar subsurface defects are inverted to determine an enhanced representation of the shape and size of planar subsurface defects. The inversion is effected by an algorithm. The inversion algorithm can also be used in the improvement of the spatial resolution of such defects. The calculations are performed on Macintosh IIfx computers for 128 by 128 pixel images. The inversion time is 1 minute or less.

A study to choose metallic, formed-in-place (FIP) membranes that would hold a minimum of five logs of Lactococcus lactis ssp. lactis, determined the microbial content of whey while passing a minimum of 50% of the whey protein, immunoglobulin G (IgG), and calculated the logarithmic reduction values (LRV) of lactococci and rejection of IgG. The raising of lactococci to 109 from 107 did not influence IgG rejection. Of the 20 membranes developed on traditional stainless steel substrates, not a single one attained 5LRV and passed more than 50% IgG.

A method for the measurement of anisotropic thermal diffusivities parallel to a solid sample surface is presented. The mirage effect is the basis of the approach and data from rare earths, ceramics and polymers were analyzed by multiparameter least-squares regression fitting. Variance estimations were used to test the reliability of the measurements. The utility of the mirage measurement technique for materials with very low-diffusivity was established.

The effect of pH on the separation of whey proteins using charged, formed-in-place membranes showed that decrease in pH and increase in total positive charges results in increased rejection of proteins. This principle was used in selective enrichment of immunoglobulin G from whey. Whey was concentrated and diafiltered at pH 5.0 with 80 to 85% recovery of IgG. The diafiltered material was refiltered at pH 7.0 using the same formed-in-place membrane. IgG passed into the permeate with the other whey proteins but large complex micelles and lipoproteins were removed. Thus, IgG may be enriched using formed-in-place membranes by manipulating pH and charges.

The technique of sonic infrared imaging (SIR) consists of the excitation of an object with a short pulse of 15 to 40 kHz sound, in combination with IR imaging of the object’s surface temperature as a function of time. Sonic infrared imaging is effective for detecting surface and subsurface cracks. The recent discovery of acoustic chaos has provided a means of greatly enhancing the effectiveness of SIR. We describe the properties of chaotic sound in the context of SIR crack detection, and show examples of the enhancement of the detectability of cracks through the use of chaotic sound. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A second, finite-element-based, computational model that contains the essential features of an actual laboratory sonic infrared imaging (SIR) experiment is described. The chaos results from the combination of the 20-kHz vibration and the bouncing of the transducer from the sample surface.

Study of isoflavone content in membrane-processed soy concentrate at different temperatures is presented.

Study of solubility, emulsifying activity and surface hydrophobicity of membrane soy protein concentrate is presented.