Detection of antigens in biologically complex fluids with photografted whole antibodies

A highly sensitive (pM), efficient (t < 20 min) detection assay was developed by designing surfaces with grafted antibodies. Through this approach, a short half-life antigen, glucagon, was rapidly detected in a biologically complex plasma/blood environment. Tailoring of graft composition eliminates the need for time-consuming blocking steps, significantly reducing antigen-antibody incubation times, while maintaining antibody specificity and activity toward target antigen. Grafted antibodies were bound through solvated, mobile polymer chains, thereby circumventing problems associated with antibody accessibility, analyte diffusion, and steric limitations. The efficiency of this assay is provided through grafting synthesized, acrylated antibodies in the presence of PEG monoacrylate. This procedure eliminates the need for blocking steps, due to a decrease in nonspecific protein interactions. These polymerizable antibodies were tethered with a range of densities while retaining biological activity. Moreover, biological activity of acrylated antibodies was compared to that of unmodified antibodies and remained comparable. The acrylated antibodies were grafted from substrate surfaces using controlled radical photopolymerization, maintaining the advantages of classical antibody immobilization techniques while providing improved detection. Through integrating this antibody conjugation chemistry and immunoassay approach with photolithographic techniques, construction of spatial patterns on a microfluidic device was demonstrated for efficient, parallel screening of multiple antigens.     

Prevalence and genetic characterization of Listeria monocytogenes in retail broiler meat in Estonia

The prevalence and genetic diversity of Listeria monocytogenes in raw broiler legs at the retail level in Estonia were studied. A total of 240 raw broiler legs (120 from Estonia and 120 of foreign origin, which had been imported to Estonia from Denmark, Finland, Hungary, Sweden, and the United States) from 12 retail stores in the two largest cities in Estonia (Tallinn and Tartu) were investigated from January to December 2002. Of these, 70% were positive for L. monocytogenes. The prevalence of L. monocytogenes in broiler legs of Estonian origin (88%) was significantly higher than in broiler legs of foreign origin (53%) (P < 0.001). Altogether, 169 (106 Estonian and 63 imported) L. monocytogenes isolates were characterized by pulsed-field gel electrophoresis (PFGE) typing after treatment with the restriction enzyme AscI. The isolates showed a wide genetic diversity, with 35 different PFGE types obtained. Of these, 11 PFGE types came only from isolates of broiler legs of Estonian origin, 4 of Danish origin, 2 of Finnish origin, and 4 of Hungarian origin. Fourteen PFGE types came from isolates of broiler legs that originated from various countries. The strains that shared the same PFGE types from isolates of Estonian origin were recovered from broiler legs that came from different stores over the course of several months. Seventy-one L. monocytogenes isolates, including all PFGE types, were serotyped, and three serotypes (1/2a, 1/2b, and 4b) were obtained. Serotype 1/2a accounted for 96% of the isolates.     

Metabolic impact of 100% fruit juice consumption on antioxidant/oxidant status and lipid profiles of adults: An Evidence-Based review

One hundred percent fruit juice (FJ) contains bioactive compounds with antioxidant activity. As such, this fruit form has the potential to improve antioxidant status and mediate outcomes influenced by redox status. A systematic review of the literature published between 1995 and 2013 was conducted using PubMed database to evaluate associations between intake of 100% FJ and markers of antioxidant/oxidant status and blood lipid levels in healthy, free-living adults ≥18 years. Data extraction and analysis was conducted according to the Academy of Nutrition and Dietetics Evidence Analysis Process. Limited evidence from ten clinical trials meeting inclusion/exclusion criteria suggests potential improvements in a variety of antioxidant or oxidants biomarkers postconsumption of 100% FJ. Weak evidence from five studies suggests that one or more blood lipid measures may be positively influenced by consumption of 100% FJ. Heterogeneity in study methodology including biomarkers, 100% FJ type, dosage, and intervention duration precludes the ability to make evidence-based recommendations regarding a specific dose-duration-juice effect. Key characteristics in study designs were identified which must either be controlled or statistically adjusted for in future investigations in order to obtain a more accurate understanding of the complex relationship between metabolic outcomes and consumption of 100% FJ in context of a healthy dietary pattern.     

Tastier and Healthier Alternatives to French Fries

ABSTRACT: The effect of both the origin and shape of potato cuts on fry quality was investigated in this study. Linear strips from the inner core of tubers were compared to those from outer tissues, both before and after processing, and strips from either specific tissues or whole peeled tubers were also evaluated against ring-shaped cuts. Both strips and rings had 0.7 cm sides and, in most cases, a volume of 4.9 cm³. They were analyzed for moisture content, antioxidants, asparagine, and reducing sugars. The material was then blanched, dipped in 0.5% disodium acid pyrophosphate and 0.3% glucose, dried at 77 °C, par-fried in soybean oil at 191 °C, and finish-fried at 168 °C. The fried product was analyzed for sensory characteristics and oil, salt, and acrylamide content. Our results showed that strips from the inner core absorbed 28% more oil and exhibited inferior sensory characteristics compared to strips from the outer parts. The extended drying and frying times needed to match the crispness and flavor of inner strips to those of regularly fried outer strips resulted in a further increased absorption of oil and, importantly, triggered a 163% increase in levels of the toxic Maillard reaction product acrylamide. Potato rings consisted of higher dry matter material, contained more antioxidants, and had a lower surface-to-volume ratio than the conventional linear strips. Upon processing, they also absorbed 22% less oil, contained 26% less salt, and displayed superior sensory properties. Thus, ring fries may represent an attractive alternative to French fries as processed staple food.     

Academic task persistence of normally achieving ADHD and control boys: Self-evaluations, and attributions.

The authors examined academic task persistence, pretask expectancies, self-evaluations, and attributions of boys with attention-dcficit/hyperactivity disorder (ADHD) as compared with control boys. Participants were 83 ADHD boys and 66 control boys, all normally achieving. Prior to the task, performance expectancies were assessed. After a success-failure manipulation with find-a-word puzzles, performance on subsequent trials, self-evaluations, and attributions were evaluated. Compared with controls, ADHD boys solved fewer test puzzles, quit working more often, and found fewer words on a generalization task. Consistent with these behavioral findings, research assistants rated ADHD boys as less effortful and less cooperative than control boys. Although ADHD boys did not differ significantly from controls in their posttask self-evaluations, they did differ significantly from controls in some aspects of their attributions. Attributional data indicated that ADHD boys endorsed luck as a reason for success more strongly and lack of effort as a reason for failure less strongly than controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development and Characterization of Degradable Thiol-Allyl Ether Photopolymers

Degradable thiol-ene photopolymer networks were formed through radically mediated step-growth reactions. Variations in the network structure were used to alter the initial and temporal moduli, mass loss profiles, and equilibrium swelling ratios. Mass loss rates varied with changes in the solvent concentration, monomer molecular weight, average monomer functionality, and concentration of degradable linkages. The time required for the networks to degrade completely ranged from 1.20 ± 0.01 to 24.5 ± 0.1 days, which corresponded to hydrolysis rates of 0.18 ± 0.01 and 0.021 ± 0.0003 day⁻¹. Initial moduli also varied considerably as a function of network structure, ranging from 150 ± 35 to nearly 5000 ± 100 kPa, and initial equilibrium swelling ratios ranged from 2.5 ± 0.01 to 18.7 ± 2. Collectively, these results demonstrate how the material properties and the mass loss behavior of thiol-ene networks can be independently tuned for specific applications.     

Measuring the velocity fields of granular flows – Employment of a multi-pass two-dimensional particle image velocimetry (2D-PIV) approach

Measuring velocity fields plays a crucial role in investigating the dynamics of granular flows, which can improve the modeling of hazardous geophysical flows (e.g. avalanches and debris flows) and the control of powder flows in industrial applications. Non-invasive optical methods are invaluable tools for estimating this physical quantity at the laboratory scale. Despite the recent improvements of particle image velocimetry (PIV) algorithms, the employment of PIV to granular flows is still a non-trivial application, where there are several specific aspects to be carefully addressed. Here, we address the main challenges of granular PIV applications and systematically test the open-source window deformation multi-pass code, PIVlab [Thielicke and Stamhuis, J. Open Res. Soft., 2014], for dry granular flows in rotating drum and chute flow experiments. Three granular media (glass spheres, Ottawa sand and acetalic resin beads) with different optical properties are used as a broad test bench for validating the PIV approach. As well, comparisons between the estimations by PIVlab and those obtained by the commercial code, IDT ProVision-XS, are reported, where the advantages of the multi-pass approach are highlighted. This extensive experimental investigation allowed the evaluation of the accuracy of PIVlab in granular flow applications and also helped to assess the reliability of measurements of second-order statistics, such as the granular temperature. Finally, a guideline for setting a reliable PIV arrangement is suggested.     

A comparative study of Desktop, Fishtank, and Cave systems for the exploration of volume rendered confocal data sets

We present a participant study that compares biological exploration tasks using volume renderings of laser confocal microscopy data across three environments which vary in level of immersion. For the tasks, data, and visualization approach used in our study, we found that subjects qualitatively preferred and quantitatively performed better in environments with greater levels of immersion. Subjects performed real-world biological data analysis tasks that emphasized understanding spatial relationships including characterizing the general features in a volume, identifying co-located features, and reporting geometric relationships such as whether clusters of cells were coplanar. After analyzing data in each environment, subjects were asked to choose which environment they wanted to analyze additional data sets in--subjects uniformly selected the Cave environment.     

A hybrid methodology for enhancing reliability of large systems in conceptual design and its application to the design of a multiphase flow station

This paper presents a hybrid methodology for conceptual design of large systems with the goal of enhancing system reliability. It integrates the features of several design methodologies and maintenance planning concepts with the traditional reliability analysis. The methodology considers the temporal quality characteristic “reliability” as the main objective and determines the optimal system design. Key ideas from several design methodologies, namely axiomatic design, robust design, and the theory of inventive problem solving, have been integrated with the functional prioritization framework provided by reliability-centered maintenance. A case study of the conceptual design of a multiphase pumping station for crude oil production is presented. The methodology provides a new design tool for determining system configurations with enhanced reliability taking into account maintenance resources and variability.