Neuropsychological deficits in asymptomatic atrial fibrillation

The metabolism of pyrene by Penicillium glabrum strain TW 9424, a strain isolated from a site contaminated with polycyclic aromatic hydrocarbons (PAHs) was investigated in submerged cultures. The metabolites formed were identified as 1-hydroxypyrene, 1,6- and 1, 8-dihydroxypyrene, 1,6- and 1,8-pyrenequinone, and 1-pyrenyl sulfate. In addition, two new metabolites were isolated and identified by UV, 1H nuclear magnetic resonance, and mass spectroscopy as 1-methoxypyrene and 1,6-dimethoxypyrene. Experiments with [methyl-3H]S-adenosyl-l-methionine (SAM) revealed that SAM is the coenzyme that provides the methyl group for the methyltransferase involved. To our knowledge, this is the first time that methoxylated metabolites of PAHs have been isolated from fungal cultures.     

Properties of polytetrafluoroethylene (PTFE) paste extrudates

In this work, we have studied the effects of extrusion die design, resin molecular structure, and lubricant concentration on the properties of PTFE paste extrudates by performing macroscopic extrusion pressure measurements, Raman spectroscopy, differential scanning calorimetry and mechanical testing on the extrudates. Five resins of different molecular structures were tested. We have found that a balance between fibril quantity and quality (in terms of fibril orientation and continuousness) is necessary to ensure acceptable products, as illustrated through the effects of the operating variables on the extrudate tensile strength. The number of fibrils formed during extrusion can be increased by extruding the paste through a die of larger reduction ratio or by decreasing the lubricant content in the paste, thereby increasing the extrusion pressure. However, excessive pressure will cause fibril breakage. By using a die of larger entrance angle, the extent of fibrillation is also increased, although the quality of the fibrils is somewhat compromised. Increasing the die aspect (L/D) ratio does not increase the extent of fibrillation. However, it increases the degree of fibril orientation and ensures smoother extrudate. Finally, we have found that extrudates obtained using a paste of higher molecular weight are mechanically superior.     

Introducing a C-interglycosidic bond in a biologically active pentasaccharide hardly affects its biological properties

We describe here the synthesis and the biological activity of a 'C-pentasaccharide', a new analogue of the antithrombin III (AT III) binding region of heparin containing a methylene bridge in place of an interglycosidic oxygen atom. The affinity for AT III and the anti-factor Xa activity of this compound have been compared with that of the corresponding selected 'O-pentasaccharide'. Such a structural modification slightly decreased the affinity of this compound for AT III as well as its anti-factor Xa activity (880 +/- 40 anti-Xa units versus 1180 +/- 30 anti-Xa units for the C-pentasaccharide and the O-pentasaccharide, respectively). This compound therefore represents the first example of a new class of anti-factor Xa pentasaccharides containing a C-interglycosidic bond.     

Electrosyntheses of disaccharides from phenyl or ethyl 1-thioglycosides

Age- and sex-specific reference intervals of data derived from a healthy paediatric population are presented for retinol, beta-carotene, alpha-tocopherol, cholesterol and related proteins in serum. Age was an important covariate for the micronutrient concentration values. Retinol was highly correlated with alpha-tocopherol and cholesterol. Strong correlation was found with both beta-carotene and cholesterol. Serum levels were considered for their appropriateness as indicators of micronutrient status.     

Optimization of FX-70 refrigerant evaporative heat transfer and fluid flow characteristics inside the corrugated tubes using multi-objective genetic algorithm

In this study, the heat transfer optimization (evaporation) and the specification of the FX-70 zeotropic refrigerant flow inside a corrugated pipe have been investigated. Despite the low HTC (HTC), this type of refrigerant is highly applicable in low or medium temperature engineering systems during the evaporation process. To eliminate this defect, high turbulence and proper mixing are required. Therefore, using heat transfer (HT) augmentation methods will be necessary and effective. In order to find the most favorable operating conditions that lead to the optimum combination of pressure drop (PD) and HTC, empirical data, neural networks, and genetic algorithms (GA) for multi-objective (MO) (NSGA II) are used. To investigate the mentioned cases, the geometric parameters of corrugated pipes, vapor quality, and mass velocity of refrigerant were studied. The results showed that with vapor quality higher than 0.8 and corrugation depth and pitch of 1.5 and 7 mm, respectively, we would achieve the desired optimum design.     

Compact MOS Implementation of a Reaction-Diffusion CNN

A biologically inspired single layer cellular neural network (CNN) with trigger wave formation capability is presented. A novel compact MOS cell circuit is proposed which exhibits a third order I-V characteristic with negative differential resistance (NDR). Certain D.C. characteristics of both the proposed cell and the network are described and corresponding theoretical estimations are presented. It is shown that the CNN formed by resistive coupling of these cells has very low complexity and realizes a reaction-diffusion system. The dynamical network behavior is demonstrated by transient simulations of a 2D cell array at the circuit level.Koray Karahalilolu received the B.Sc., M.Sc., and Ph.D. degrees in electrical engineering from Boaziçi University, Istanbul, Turkey, in 1993, 1996, and 2002, respectively.Currently he is a Research Assistant Professor with the Department of Electrical Engineering, University of Nebraska, Lincoln. He also worked as a teaching assistant with the Department of Electrical and Electronics Engineering at Boaziçi University.His research interests include VLSI neural networks, device modeling and simulation, analog circuits and systems, and nanodevice system applications.Sina Balkr received the B.S. degree in electrical engineering from Boaziçi University, Istanbul, Turkey, in 1987, and the M.S. and Ph.D. degrees in electrical engineering from Northwestern University, Evanston, IL, in 1989 and 1992, respectively.Between August 1992 and August 1998, he was with the Department of Electrical and Electronics Engineering, Boaziçi University, as an Assistant and Associate Professor. Currently, he is with the Department of Electrical Engineering, University of Nebraska-Lincoln. His research interests include CAD of VLSI systems, analog VLSI design automation, and focal-plane computation arrays for image processing.     

Kernel regression for image processing and reconstruction.

In this paper, we make contact with the field of nonparametric statistics and present a development and generalization of tools and results for use in image processing and reconstruction. In particular, we adapt and expand kernel regression ideas for use in image denoising, upscaling, interpolation, fusion, and more. Furthermore, we establish key relationships with some popular existing methods and show how several of these algorithms, including the recently popularized bilateral filter, are special cases of the proposed framework. The resulting algorithms and analyses are amply illustrated with practical examples.     

Sublayer assisted by hydrophilic and hydrophobic ZnO nanoparticles toward engineered osmosis process

Hydrophilic and hydrophobic polyethersulfone (PES)-zinc oxide (ZnO) sublayers were prepared by loading of ZnO nanoparticles into PES matrix. Both porosity and hydrophilicity of the hydrophilic sublayer were increased upon addition of hydrophilic ZnO, while these were decreased for the hydrophobic sublayer. In addition, the results demonstrated that the hydrophilic membrane exhibited smaller structural parameter (S value or S parameter or S), which is beneficial for improving pure water permeability and decreasing mass transfer resistance. In contrast, a higher S parameter was obtained for the hydrophobic membrane. With a 2M NaCl as DS and DI water as FS, the pure water flux of hydrophilic TFN0.5 membrane was increased from 21.02 L/m² h to 30.06 L/m² h and decreased for hydrophobic TFN0.5 membrane to 14.98 L/m² h, while the salt flux of hydrophilic membrane increased from 10.12 g/m² h to 17.31 g/m² h and decreased for hydrophobic TFN0.5 membrane to 3.12 g/m² h. The increment in pure water permeability can be ascribed to reduction in S parameter, which resulted in reduced internal concentration polarization (ICP). The current study provides a feasible and low cost procedure to decrease the ICP in FO processes.