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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

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 [...]

Objectives: To evaluate the activity of intravesical mitomycin‐C (MMC) to ablate recurrent low‐risk non‐muscle‐invasive bladder cancer (NMIBC) and assess whether it may enable patients to avoid surgical intervention for treatment of recurrence. Patients and Methods: CALIBER is a phase II feasibility study. Participants were randomized (2:1) to treatment with four once‐weekly MMC 40‐mg intravesical instillations (chemoablation arm) or to surgical management. The surgical group was included to assess the feasibility of randomization. The primary endpoint was complete response to intravesical MMC in the chemoablation arm at 3 months, reported with exact 95% confidence intervals (CIs). Secondary endpoints included time to subsequent recurrence, summarized by Kaplan–Meier methods. Results: Between February 2015 and August 2017, 82 patients with visual diagnosis of recurrent low‐risk NMIBC were enrolled from 24 UK hospitals (chemoablation, n = 54; surgical management, n =28). The median follow‐up was 24 months. Complete response at 3 months was 37.0% (20/54; 95% CI 24.3–51.3) with chemoablation and 80.8% (21/26; 95% CI 60.6–93.4) with surgical management. Amongst patients with complete response at 3 months, a similar proportion was recurrence‐free by 12 months in both groups (84%). Amongst those with residual disease at 3 months, the 12‐month recurrence‐free proportion was lower in the surgical management group (40.0%) than in the chemoablation group (84%). Recruitment stopped early as chemoablation did not meet the prespecified threshold of 45% complete responses at 3 months. Conclusion: Intravesical chemoablation in low‐risk NMIBC is feasible and safe, but did not demonstrate sufficient response in the present trial. After chemoablation there may be a reduction in recurrence rate, even in non‐responders, that is greater than with surgery alone. Further research is required to investigate the role and optimal schedule of neoadjuvant intravesical chemotherapy prior to surgery for NMIBC. [ABSTRACT FROM AUTHOR]

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.

Objective Here, we present a 7-year-old patient suffering from severe haemolytic anaemia. The most common cause of chronic hereditary non-spherocytic haemolytic anaemia is red blood cell pyruvate kinase (PK-R) deficiency. Because red blood cells rely solely on glycolysis to generate ATP, PK-R deficiency can severely impact energy supply and cause reduction in red blood cell lifespan. We determined the underlying cause of the anaemia and investigated how erythroid precursors in the patient survive. Methods PK activity assays, Western blot and Sanger sequencing were employed to determine the underlying cause of the anaemia. Patient erythroblasts were cultured and reticulocytes were isolated to determine PK-R and PKM2 contribution to glycolytic activity during erythrocyte development. Results We found a novel homozygous mutation (c.583G>A) in the PK-R coding gene ( PKLR). Although this mutation did not influence PKLR mRNA production, no PK-R protein could be detected in the red blood cells nor in its precursors. In spite of the absence of PK-R, the reticulocytes of the patient exhibited 20% PK activity compared with control. Western blotting revealed that patient erythroid precursors, like controls, express residual PKM2. Conclusions We conclude that PKM2 rescues glycolysis in PK-R-deficient erythroid precursors. [ABSTRACT FROM AUTHOR]

2008;121:326-336. OBJECTIVE: Children in developing countries are at a high risk for zinc deficiency. Supplemental zinc has previously been shown to provide therapeutic benefits in diarrhea. The objective of this [...]

Even though red blood cell (RBC) vesiculation is a well-documented phenomenon, notably in the context of RBC aging and blood transfusion, the exact signalling pathways and kinases involved in this process remain largely unknown. We have established a screening method for RBC vesicle shedding using the Ca2+ ionophore ionomycin which is a rapid and efficient method to promote vesiculation. In order to identify novel pathways stimulating vesiculation in RBC, we screened two libraries: the Library of Pharmacologically Active Compounds (LOPAC) and the Selleckchem Kinase Inhibitor Library for their effects on RBC from healthy donors. We investigated compounds triggering vesiculation and compounds inhibiting vesiculation induced by ionomycin. We identified 12 LOPAC compounds, nine kinase inhibitors and one kinase activator which induced RBC shrinkage and vesiculation. Thus, we discovered several novel pathways involved in vesiculation including G protein-coupled receptor (GPCR) signalling, the phosphoinositide 3-kinase (PI3K)- Akt (protein kinase B) pathway, the Jak-STAT (Janus kinase-signal transducer and activator of transcription) pathway and the Raf-MEK (mitogen-activated protein kinase kinase)-ERK (extracellular signal-regulated kinase) pathway. Moreover, we demonstrated a link between casein kinase 2 (CK2) and RBC shrinkage via regulation of the Gardos channel activity. In addition, our data showed that inhibition of several kinases with unknown functions in mature RBC, including Alk (anaplastic lymphoma kinase) kinase and vascular endothelial growth factor receptor 2 (VEGFR-2), induced RBC shrinkage and vesiculation. [ABSTRACT FROM AUTHOR]

Abstract: Antioxidant activity of chitosans of different molecular weights (30, 90 and 120kDa chitosan) in salmon (Salmo salar) was investigated. The progress of oxidation was monitored by employing the 2-thiobarbituric acid-reactive substances (TBARS) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assays. In general, all chitosans exhibited antioxidative activities in salmon. The addition of chitosans to salmon reduced lipid oxidation for seven days of storage. The TBARS values of salmon containing chitosan were significantly lower than those of the control (p <0.01). At 0.2% (w/v) and 0.5% (w/v) concentrations, the TBARS with chitosan addition was decreased by 75% and 45%, respectively, over 15 days. At 1% concentration, the TBARS value with native chitosan addition was decreased by 32% after 15 days of storage. 90kDa chitosan showed an increased DPPH free radical-scavenging activity with increasing concentration in the range of 0.2–1% (w/v). The free radical-scavenging activity of the 0.2mM DPPH solution was saturated by 30kDa chitosan at a concentration of ⩾0.7% (w/v), resulting in a strong antioxidant activity of approximately 85%. This was comparable to the DPPH free radical-scavenging activity of BHT. [Copyright &y& Elsevier]

Studies of the sediments of Hamilton Harbour, Lake Ontario, Canada, have shown variable degrees of pollution with a large number of organic and inorganic pollutants. Three areas in the Harbour – Windemere Basin, Cootes Paradise and Randle Reef – exhibited particularly high levels of contaminants, with concomitant impacts on benthic organisms. Sediment samples examined in this study were taken from a site in Randle Reef in Hamilton Harbour and a station (LE 23) in Lake Erie used as a reference sample. The samples were subjected to chemical fractionation to remove organic contaminants, with one fraction being used as total extract, and another aliquot being subjected to silica gel fractionation to give four fractions. Each fraction was chemically analysed and an aliquot used for bioassays following exchange with dimethylsulfoxide. Standard biotests were performed with Daphnia magna, Hyalella azteca, Pimephales promelas (fathead minnows) and Selenastrum capricornutum. Results from direct sediment contact bioassays indicated that sediment from Randle Reef is highly toxic, whereas the Lake Erie sample had no observable impacts. Total extract when added at 1% to the bioassays replicated the solid phase with acute toxicity for Randle Reef, and no effect on Lake Erie. For the silica gel fractionation, Fraction 1 (F1) showed similar toxicity as the total extract, even at low additions, whereas F2–4 gave variable and inconclusive results. F1 eluted with hexane contained the non-polar fractions, predominantly the polyaromatic hydrocarbons, and these compounds are the most likely causative agents for the highly acute toxicity observed in the sediment of Randle Reef. [ABSTRACT FROM AUTHOR]

The antimicrobial activity of native chitosan was compared to that of lipase-degraded chitosan. The effects of O-carboxymethylated (O-CM) substitution on native (molecular weight, 120; degree of deacetylation, 84.71%) and lipase-degraded chitosans were also investigated. The antimicrobial activity of native chitosan was more extensive than that of lipase-degraded chitosan; however, lipase-degraded chitosan was still highly effective and more water-soluble. O-CM chitosan derived from degraded chitosan was more effective than O-CM chitosan derived from native chitosan. O-CM substitution enhanced lipasedegraded chitosan's antimicrobial activity without reducing its solubility. [ABSTRACT FROM AUTHOR]

A process for selective enrichment of immunoglobulins has been developed using formed-in-place membranes on sintered stainless steel tubes. The process employs both size exclusion and protein charge manipulation around the isoelectric point of proteins to selectively reject or pass components of the stream. Volume recoveries of 95% (20X concentration) could be achieved with a single filtration without loss of fractionation capabilities. The large initial volume reduction allows for small subsequent diafiltration volumes and insures optimization of fractionation while minimizing total processing volume. The process has been used to enrich proteins representing a small percentage of the total protein from a large feed volume. As an example, immunoglobulin G (IgG) from cheese whey was enriched from 8% to 20% of total whey protein with a 90% recovery of the IgG. [ABSTRACT FROM AUTHOR]

Focuses on the influence of unionization and estimated Phillips curve. Relationship between rates of wage inflation and unemployment levels; Structure of collective bargaining; Functions of the degree of labor force organization.

Provides information on research carried out which examined the plastic yield and fracture of rubber-modified polystyrene specimens under tensile load. What the experimental procedure consisted of; Analysis of single-edge-notched and dog-bone-shaped test coupons; Results of the research carried out.