Microdevices for Continuous Sized Based Sorting by AC Dielectrophoresis

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.In this project, various microfluidic devices are designed for microparticles and cells separation. The dominant regions of dielectrophoresis among other AC Electrokinetic transport mechanisms are predicted. Flow behaviors of particles for each design parameter are modeled and simulated using COMSOL Multiphysics 4.3a software. Lab-on-a-chip devices having a Ti interdigitated electrode layer on a glass substrate and a PDMS microchannel are fabricated to investigate the most effective design solution for separating particles based on their sizes. Polystyrene particles with different diameters of 3.2 μm and 9.8 μm are used in our experiments and experiments with circulating tumor cells (CTCs) are in progress

A virtual reality collaborative planning simulator and its method for three machines in a fully mechanized coal mining face

The existing automatic control program and its parameters for three machines in a fully mechanized Coal Mining face are static and simplex and are therefore inadequate for satisfying the complex and dynamic environment of underground coal mines. To overcome this problem, a collaborative mathematical model is established that includes the effects of a dynamic environment. A virtual reality collaborative planning simulator with methods for the three machines is also proposed based on a multi-agent system. According to the dynamic characteristics of the environment, equipment, and technologies, a fully mechanized Unity3D simulator (FMUnitySim) is designed in terms of multiple factors and multiple dimensions. The factors affecting the coordinated operation of the three machines are analyzed and modeled. The communication modes, coordination, and redundant sensing process among multiple agents, which include the shearer agent and the scraper conveyor agent, are also investigated in detail. Using this system, the key parameters of the three machines can be planned and adjusted online to design and distinctly observe the corresponding collaborative simulations of coordinated operation with multiple perspectives and in real time. Tests of different maximum shearer haulage speeds for regular or reverse transporting coal are designed; their key parameters, including the average shearer haulage speed, average follower distance, and average scraper conveyor load, are planned and simulated using FMUnitySim. The optimal parameter combination is obtained by analyzing and comparing the simulation results. The proposed FMUnitySim offers an effective means and theoretical basis for the rapid planning and safe automatic production of a fully mechanized Coal Mining face

Meta-analysis identifies novel risk loci and yields systematic insights into the biology of male-pattern baldness

Life & Brain GmbH; the BONFOR programme of the University of Bonn; and the Agency for Science, Technology and Research (A*STAR). M.M.N. is a member of the DFG Excellence Cluster ImmunoSensation

Zebrafish regenerate full thickness optic nerve myelin after demyelination, but this fails with increasing age

INTRODUCTION: In the human demyelinating central nervous system (CNS) disease multiple sclerosis, remyelination promotes recovery and limits neurodegeneration, but this is inefficient and always ultimately fails. Furthermore, these regenerated myelin sheaths are thinner and shorter than the original, leaving the underlying axons potentially vulnerable. In rodent models, CNS remyelination is more efficient, so that in young animals (but not old) the number of myelinated axons is efficiently restored to normal, but in both young and old rodents, regenerated myelin sheaths are still short and thin. The reasons for these differences in remyelination efficiency, the thinner remyelinated myelin sheaths compared to developmental myelin and the subsequent effect on the underlying axon are unclear. We studied CNS remyelination in the highly regenerative adult zebrafish (Danio rerio), to better understand mechanisms of what we hypothesised would be highly efficient remyelination, and to identify differences to mammalian CNS remyelination, as larval zebrafish are increasingly used for high throughput screens to identify potential drug targets to improve myelination and remyelination. RESULTS: We developed a novel method to induce a focal demyelinating lesion in adult zebrafish optic nerve with no discernible axonal damage, and describe the cellular changes over time. Remyelination is indeed efficient in both young and old adult zebrafish optic nerves, and at 4 weeks after demyelination, the number of myelinated axons is restored to normal, but internode lengths are short. However, unlike in rodents or in humans, in young zebrafish these regenerated myelin sheaths were of normal thickness, whereas in aged zebrafish, they were thin, and remained so even 3 months later. This inability to restore normal myelin thickness in remyelination with age was associated with a reduced macrophage/microglial response. CONCLUSION: Zebrafish are able to efficiently restore normal thickness myelin around optic nerve axons after demyelination, unlike in mammals. However, this fails with age, when only thin myelin is achieved. This gives us a novel model to try and dissect the mechanism for restoring myelin thickness in CNS remyelination. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40478-014-0077-y) contains supplementary material, which is available to authorized users

An investigation of pressure stiffness coupling in brush seals

Pacific Center of Thermal Fluid Engineering;International Journal of Rotating Machinery;American Society of Mechanical Engineering (ASME) International;Transactions of the ASME Journal of Turbomachinery;Trans. ASME J. Eng. Gas Turbines Power11th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, ISROMAC-11 -- 26 February 2006 through 2 March 2006 -- Honolulu, HI -- 92934In recent years, brush seals found common use in turbomachinery applications. There are a number of seal locations on gas turbines that have significant performance derivatives. These include the compressor discharge, bearing seals, turbine interstage packings, and the bucket tips. While brush seal applications keep expanding towards more challenging locations, the need for better understanding of seal dynamic behavior also increases. Inherent flexibility of brush seals allows fibers to compact under pressure load. Due to the frictional interaction between the fibers and the backing plate as well as within the fibers themselves, brush seals are known to exhibit pressure stiffening and hysteresis behavior. While hysteresis affects seal performance after a rotor excursion, pressure stiffening is critical in determining heat generation and seal wear during hard rubs. It is necessary to understand the physical behavior of a brush seal under the operating conditions, and to be capable of quantifying seal life and performance as functions of both operating parameters and seal design parameters. In this paper, a 3-D finite element model is used in order to explore pressure-stiffness coupling behavior. The analysis includes all the frictional effects to better calculate resulting seal stiffness and tip forces. The results indicate that rotor interference has some effect on seal tip forces in the absence of any pressure loading. However, upon application of small pressure loads, seal stiffness is generally dominated by pressure-stiffness coupling. Results also indicate presence of hysteresis when rotor excursion is removed under pressure load. Copyright © 2006 by ISROMAC-11

Synthesis and in-vitro antimicrobial and antimutagenic activities of some novel 2-(2-hydroxybenzylideneamino)-5,7-dihydro-4hthieno[ 2,3-c]pyran-3-carbonitrile derivatives

In this investigation, a series of some novel 2-(2-hydroxybenzylideneamino)-5,7-dihydro-4Hthieno[ 2,3-c]pyran-3-carbonitriles (4a-f) have been synthesized. These substances have all been examined for antibacterial activities against pathogenic strains Listeria monocytogenes 4b, Staphylococcus aureus, Escherichia coli, Salmonella typhi H, Pseudomonas putida, Brucella abortus, Shigella dysenteriae.Thype 7, Staphylococcus epidermis, Micrococcus luteus, Bacillus cereus, Enterobacter aerogenes and antifungal activity against Candida albicans. Most of the studied compounds were found effective against bacteria and yeast. Compound 4f exhibited activity against Pseudomonas putida, Brucella abortus, Staphylococcus aureus, Candida albicans and 4c Brucella abortus, Staphylococcus epidermis comparable to standard antibiotics. In addition, the anti-genotoxic activity of these substances was evaluated by a micronucleus (MN) test. Among the synthesized compounds, 4c was found to have the most anti-mutagenic effect against AFB1. It was also found that different concentrations of these substances suppressed the mutagenic effects of Aflatoxin B1 (AFB1) in the MN test (however 10 µM is the most effective dose). It seems that the antimutagenic effects of these substances may originate from their antioxidant potency or reaction of the aflatoxine lactone carbonyl functional group