Concanavalin A immobilized magnetic poly(glycidyl methacrylate) beads for antibody purification

Concanavalin A (Con A) immobilized magnetic poly(glycidyl methacrylate) (mPGMA) beads in monosize and spherical for (1.62 μm in diameter) were used for the purification of human immunoglobulin G (IgG) from human plasma. Con A was immobilized by covalent binding onto the mPGMA beads. The maximum IgG adsorption on the mPGMA-Con A beads was observed at pH 6.0. The nonspecific IgG adsorption onto the plain mPGMA beads was very low (0.22 mg/g). Scatchard analysis of the adsorption isotherm for IgG on mPGMA-Con A beads showed an affinity constant (K_a) of 1.39 × 10⁵ M⁻¹ and a theoretical maximum adsorption capacity of 109.1 mg/g. An apparent IgG adsorption capacity of 66.2 mg/g was observed under the experimental conditions. IgG adsorption capacity from human plasma was observed as 48.0 mg/g. The adsorption of human serum albumin from plasma was 2.0 mg/g. The total protein adsorption was determined to be 50.0 mg/g. IgG molecules could be repeatedly adsorbed and eluted with the mPGMA-Con A beads without noticeable loss in the IgG adsorption capacity. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

The Effects of Electromagnetic Brake on Liquid Steel Flow in Thin Slab Caster

Computational fluid dynamics (CFD) model with magneto hydro dynamics (MHD) is developed for a thin slab caster to investigate the effects of electromagnetic brake (EMBr) on liquid steel flow in continuous casting mold and to determine the EMBr practices which lead to optimal flow structure. Particle Image Velocimetry (PIV) tests in water model and meniscus flow measurements in real caster are performed to validate the predictions obtained with CFD models. The performance of different submerged entry nozzle designs, SEN 1 and SEN 2, are evaluated. The effects of nozzle submergence in relation to the applied magnetic field on mold flow structure are quantified. There are significant differences between flow structures obtained with SEN 1 and SEN 2, even though both designs have fundamental similarities and contain four ports. EMBr mainly reduces the meniscus velocities for SEN 2 as opposed to the foremost influence of EMBr for SEN 1 that is to significantly slow down the downward jet coming from the bottom ports. In addition, reducing the EMBr strength for shallow nozzle submergence and increasing the EMBr strength for deep nozzle submergence help to maintain similar meniscus activity for all conditions.     

A multiplexed separation of iron oxide nanocrystals using variable magnetic fields

The size-dependent magnetic properties of nanocrystals are exploited in a separation process that distinguishes particles based on their diameter. By varying the magnetic field strength, four populations of magnetic materials were isolated from a mixture. This separation is most effective for nanocrystals with diameters between 4 and 16 nm.     

Assessment of the antioxidant potential and fatty acid composition of four Centaurea L. taxa from Turkey

This paper focused on the assessment of antioxidant property and fatty acid composition of four Centaurea species. The antioxidant activity of its methanol extract was evaluated by several in vitro experiments including phosphomolybedum assay, DPPH assay, β-carotene/linoleic acid, ferric and cupric reducing power. Total phenolic and flavonoid contents were also evaluated. The methanol extract of Centaurea pulcherrima var. pulcherrima showed the superior free radical scavenging activity, linoleic acid inhibition capacity, reducing power and also had the highest total phenolic content. A significant relationship between antioxidant capacity and total phenolic components was found. The oils of Centaurea taxa were also analysed for fatty acid concentration by gas chromatography. The principal fatty acids in the species were palmitic acid (23.38–30.49%) and linoleic acid (20.19–29.93%). These findings suggest that the Centaurea species could be used as a potential source of new natural antioxidants and unsaturated fatty acids in food industry, cosmetics and pharmaceutical preparations.     

Fatty Acid Composition and Trans Fatty Acids in Crisps and Cakes in Turkey's Markets

In this study, trans fatty acid and fatty acid composition of 57 crisps and 50 cakes sold in the markets in Turkey were determined. C 18:1, oleic acid, was the major fatty acid in all crisps and cake samples. The percentages of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and polyunsaturated fatty acids (PUFAs) ranged between 27.98–46.57, 35.73–47.57, and 9.86–35.90 g/100 g fatty acids in crisps and 35.41–54.03, 25.89–44.87, and 10.52–26.97 g/100 g fatty acids in cakes, respectively. Total trans fatty acids ranged from 0.02 to 1.35 g/100 g fatty acids in crisps and 0.00 to 5.05 g/100 g fatty acids in cakes, respectively.     

Effect of different denture adhesives on retention of complete dentures: an in vivo study

The increase in prevalence of tooth loss with the effect of population aging produces the growing need for complete dentures. The success and acceptance of complete dentures by the patient depends on sufficient retention and stability. Therefore, denture adhesives are regularly used by denture wearers to improve the function of complete denture. We evaluated the effect of three different denture adhesives (Corega, Protefix, Fittydent) on the retention of maxillary complete denture (MCD) using with digital dynamometer (DD). For this purpose, denture adhesives were applied on MCDs of 30 participants. After chewing procedure, the force was applied at 45° to the palatal surface of denture by DD. Dislodgement force was recorded by means of Newton. There were four measurements on each patient including; group of control: Group C; Group CR: Corega; Group F: Fittydent; Group P: Protefix. The result of the study was statistically evaluated by using analysis of variance (ANOVA) and Tukey HSD test. Statistics of ANOVA showed a significant difference among all the four groups (p = 0.00, <0.05). Tukey HSD test indicated that there was a statistical difference between Group F and the other groups, but there was not a significant difference between the other groups. The highest adhesive strength value was observed in group F, the lowest in group C. Use of denture adhesives improved the retentive strength of complete denture.     

Improved wear properties of magnesium matrix composite with the addition of fullerene using semi powder metallurgy

The present study aims to fabricate fullerene (C60) reinforced magnesium matrix composite via semi powder metallurgy in hot press system under high purity argon atmosphere. Improvement of wear resistance of pure magnesium with the addition of fullerene is also aimed with this study. Hardness and wear tests at room temperature were performed to investigate the mechanical effect of fullerene nanoparticles. Microstructures of fabricated composites were characterized using Scanning Electron Microscope (SEM). Results clearly show that hardness performance was improved up to 0.5 wt. % fullerene addition directly. A uniform distribution was also achieved according to the mapping and line EDX analysis for the lower content of fullerene. Agglomeration of fullerene was observed for 1 wt. % reinforced composite. Wear performances of pure magnesium were also improved when harder fullerene reinforcements incorporated into the matrix. Abrasion and oxidation were main wear mechanism for unreinforced and fullerene reinforced composites. Enhancement of hardness and wear performances might be attributed to the high specific surface area of fullerene and achievement of uniform distribution of reinforcement in magnesium matrix.     

Frequency and focal region properties of random sparse arrays

The concept of a random array relay, in terms of a sparse array, is introduced. The basic idea is to replace the relatively compact radiating structures encountered in conventional communication systems with widely and randomly dispersed radiating systems. The frequency and focal region properties of such random sparse arrays are treated. A methodology for obtaining the expected frequency response, focal region contours and depth of field for any random sparse array is given. The technique is exemplified with results for spherical and spherical-shell arrays. In addition, computer simulation results for sample functions of frequency responses and focal region contours are presented, both to verify the theoretical results and to illustrate some of the salient properties of random sparse arrays.     

Coset networks as connectors in parallel processors

An active area of research regarding parallel computer systems deals with the design of interconnection networks. Among all interconnection networks, permutation networks play a special role as all other networks can be constructed using such networks. It was recently shown that many permutation networks reported in the literature are manifestations of coset decompositions of symmetric groups. This result is generalized here to obtain several other previously unknown permutation networks which satisfy such decompositions. In addition, analyses of the edge-count, propagation delay, fan-out, and setup time of such networks are provided. The results lead to some anomolous behavior as well as several trade-offs among these parameters. For example, it is shown that a complete bipartite graph is the fastest and most economical direct realization of a permutation network. Furthermore, it is shown that the fan-out of a network is inversely proportional to the propagation delay whereas the setup time may or may not relate to the propagation delay at all depending on the network in question. Finally, two constant fan-out implementations of these networks using O (n ^1.59) 2 × 1 multiplexers and 2 × 2 switches are presented.This work is supported in part by the National Science Foundation under Grant No: CCR-8708864.