Spatial queueing for analysis, design and dimensioning of Picocell networks with mobile users

In this work, we characterize the performance of Picocell networks in the presence of moving users. We model various traffic types between base-stations and mobiles as different types of queues. We derive explicit expressions for expected waiting time, service time and drop/block probabilities for both fixed as well as random velocity of mobiles. We obtain (approximate) closed form expressions for optimal cell size when the velocity variations of the mobiles is small for both non-elastic as well as elastic traffic. We conclude from the study that, if the expected call duration is long enough, the optimal cell size depends mainly on the velocity profile of the mobiles, its mean and variance. It is independent of the traffic type or duration of the calls. Further, for any fixed power of transmission, there exists a maximum velocity beyond which successful communication is not possible. This maximum possible velocity increases with the power of transmission. Also, for any given power, the optimal cell size increases when either the mean or the variance of the mobile velocity increases.     

Exploring the Bioactive Potentials of C60-AgNPs Nano-Composites against Malignancies and Microbial Infections

At present, the potential role of the AgNPs/endo-fullerene molecule metal nano-composite has been evaluated over the biosystems in-vitro. The intra-atomic configuration of the fullerene molecule (C₆₀) has been studied in-vitro for the anti-proliferative activity of human breast adenocarcinoma (MDA-MB-231) cell lines and antimicrobial activity against a few human pathogens that have been augmented with the pristine surface plasmonic electrons and antibiotic activity of AgNPs. Furthermore, FTIR revealed the basic vibrational signatures at ~3300 cm⁻¹, 1023 cm⁻¹, 1400 cm⁻¹ for O-H, C-O, and C-H groups, respectively, for the carbon and oxygen atoms of the C₆₀ molecule. NMR studies exhibited the different footprints and magnetic moments at ~7.285 ppm, explaining the unique underlying electrochemical attributes of the fullerene molecule. Such unique electronic and physico-chemical properties of the caged carbon structure raise hope for applications into the drug delivery domain. The in-vitro dose-dependent application of C₆₀ elicits a toxic response against both the breast adenocarcinoma cell lines and pathogenic microbes. That enables the use of AgNPs decorated C₆₀ endo fullerene molecules to design an effective anti-cancerous drug delivery and antimicrobial agent in the future, bringing a revolutionary change in the perspective of a treatment regime.     

A fast iterated conditional modes algorithm for water-fat decomposition in MRI

Decomposition of water and fat in magnetic resonance imaging (MRI) is important for biomedical research and clinical applications. In this paper, we propose a two-phased approach for the three-point water-fat decomposition problem. Our contribution consists of two components: 1) a background-masked Markov random field (MRF) energy model to formulate the local smoothness of field inhomogeneity; 2) a new iterated conditional modes (ICM) algorithm accounting for high-performance optimization of the MRF energy model. The MRF energy model is integrated with background masking to prevent error propagation of background estimates as well as improve efficiency. The central component of our new ICM algorithm is the stability tracking (ST) mechanism intended to dynamically track iterative stability on pixels so that computation per iteration is performed only on instable pixels. The ST mechanism significantly improves the efficiency of ICM. We also develop a median-based initialization algorithm to provide good initial guesses for ICM iterations, and an adaptive gradient-based scheme for parametric configuration of the MRF model. We evaluate the robust of our approach with high-resolution mouse datasets acquired from 7T MRI.     

Application of natural receptors in sensors and assays

Biosensors are analytical devices that use a biological or biologically derived material immobilized at a physicochemical transducer to measure one or more analytes. Although there are a large number of reviews on biosensors in general, there has been little systematic information presented on the application of natural receptors in sensor technology. This perspective discusses broadly the fundamental properties of natural receptors, which make them an attractive option for use as biorecognition elements in sensor technology. It analyses the current situation by reference to typical examples, such as the application of nicotinic acetylcholine receptor and G protein-linked receptors in affinity sensors and analyses the problems that need to be resolved prior to any commercialization of such devices.     

Induction of apoptosis and apoptotic mediators in balb/C splenic lymphocytes by dietary n−3 and n−6 fatty acids

The present study was designed to investigate the effect of diatery n−6 and n−3 polyunsaturated fatty acids (PUFA) on anti-CD3 and anti-Fas antibody-induced apoptosis and its mediators in mouse spleen cells. Nutritionally adequate semipurified diets containing either 5% w/w corn oil (n−6 PUFA) or fish oil (n−3 PUFA) were fed to weanling female Balb/C mice, and 24 wk later mice were sacrificed. In n−3 PUFA-fed mice, serum and splenocyte lipid peroxides were increased by 20 and 28.3% respectively, compared to n−6 PUFA-fed mice. Further, serum vitamin F levels were decreased by 50% in the n−3 PUFA-fed group, whereas higher anti0Fas- and anti-CD3-induced apoptosis (65 and 66%) and necrosis (17 and 25%), compared to the n−6 PUFA-fed group, were found when measured with Annexin V and propidium iodide staining, respectively. In addition, decreased Bcl-2 and increased Fas-ligand (Fas-L) also were observed in the n−3 PUFA-fed group compared to the n−6 PUFA-fed group. No difference in the ratio of splenocyte subsets nor their Fas expression was observed between the n−3 PUFA-fed and n−6 PUFA-fed groups, whereas decreased proliferation of splenocytes was found in n−3 PUFA-fed mice compared to n−6 PUFA-fed mice. In conclusion, our results indicate that dietary n−3 PUFA induces higher apoptosis by increasing the generation of lipid peroxides and elevating Fas-L expression along with decreasing Bcl-2 expression. A reduced proliferative response of immune cells also was observed in n−3 PUFA-fed mice.     

Fitting interrelated datasets: metabolite diffusion and general lineshapes

Objective

Simultaneous modeling of true 2-D spectroscopy data, or more generally, interrelated spectral datasets has been described previously and is useful for quantitative magnetic resonance spectroscopy applications. In this study, a combined method of reference-lineshape enhanced model fitting and two-dimensional prior-knowledge fitting for the case of diffusion weighted MR spectroscopy is presented.

Materials and methods

Time-dependent field distortions determined from a water reference are applied to the spectral bases used in linear-combination modeling of interrelated spectra. This was implemented together with a simultaneous spectral and diffusion model fitting in the previously described Fitting Tool for Arrays of Interrelated Datasets (FiTAID), where prior knowledge conditions and restraints can be enforced in two dimensions.

Results

The benefit in terms of increased accuracy and precision of parameters is illustrated with examples from Monte Carlo simulations, in vitro and in vivo human brain scans for one- and two-dimensional datasets from 2-D separation, inversion recovery and diffusion-weighted spectroscopy (DWS). For DWS, it was found that acquisitions could be substantially shortened.

Conclusion

It is shown that inclusion of a measured lineshape into modeling of interrelated MR spectra is beneficial and can be combined also with simultaneous spectral and diffusion modeling.

     

Toward wafer-scale patterning of freestanding intermetallic nanowires

Individual metal alloy nanowires of constant diameter and high aspect ratio have previously been self-assembled at selected locations on atomic force microscope (AFM) probes by the method reported in Yazdanpanah et al (2005 J. Appl. Phys. 98 073510). This process relies on the room temperature crystallization of an ordered phase of silver-gallium. A parallel version of this method has been implemented in which a substrate, either an array of micromachined tips (similar to tips on AFM probes) or a lithographically patterned planar substrate, is brought into contact with a continuous, nearly planar film of melted gallium. In several runs, freestanding wires are fabricated with diameters of 40-400 nm, lengths of 4-80 μm, growth rates of 80-170 nm s( - 1) and, most significantly, with yields of up to 97% in an array of 422 growth sites. These results demonstrate the feasibility of developing a batch manufacturing process for the decoration of wafers of AFM tips and other structures with selectively patterned freestanding nanowires.     

ESMO 2003

This paper illustrates the development of an interface for the simulator EMTDC/PSCAD for integrating an agent-based distributed application into the simulation. The custom device modules the EMTDC supports have been used to provide a channel for the agents to communicate (send and receive data) with the simulator. The main advantage of this interface is that the agents now can be developed independently, as separate JAVA applications. The application used to illustrate the features of the interface is a pilot protection scheme over a line.     

Amyloid Fibrils Aerogel for Sustainable Removal of Organic Contaminants from Water

Water contamination by organic pollutants is ubiquitous and hence a global concern due to detrimental effects on the environment and human health. Here, it is demonstrated that amyloid fibrils aerogels are ideal adsorbers for removing organic pollutants from water. To this end, amyloid fibrils prepared from β‑lactoglobulin, the major constituent of milk whey protein, are used as building blocks for the fabrication of the aerogels. The adsorption of Bentazone, Bisphenol A, and Ibuprofen, as model pollutants, is evaluated under quasi-static conditions, without use of energy or pressure. Through adsorption by amyloid fibrils aerogel, excellent removal efficiencies of 92%, 78%, and 98% are demonstrated for Bentazone, Bisphenol A, and Ibuprofen, respectively. Furthermore, the maximum adsorption capacity of amyloid fibrils aerogel for Bentazone, Bisphenol A, and Ibuprofen is 54.2, 50.6, and 69.6 mg g⁻¹, respectively. To shed light on the adsorption equilibrium process, adsorption isotherms, binding constants, saturation limits, and the effect of pH are evaluated. Finally, the regeneration of the aerogel over three consecutive cycles is studied, exhibiting high reusability with no significant changes in its removal performance. These results point at amyloid fibrils aerogels as a sustainable, efficient, and inexpensive technology for alleviating the ubiquitous water contamination by organic pollutants.