55 research outputs found
The potential use of service-oriented infrastructure framework to enable transparent vertical scalability of cloud computing infrastructure
Cloud computing technology has become familiar to most Internet users. Subsequently, there has been an increased growth in the use of cloud computing, including Infrastructure as a Service (IaaS). To ensure that IaaS can easily meet the growing demand, IaaS providers usually increase the capacity of their facilities in a vertical IaaS increase capability and the capacity for local IaaS amenities such as increasing the number of servers, storage and network bandwidth. However, at the same time, horizontal scalability is sometimes not enough and requires additional strategies to ensure that the large number of IaaS service requests can be met. Therefore, strategies requiring horizontal scalability are more complex than the vertical scalability strategies because they involve the interaction of more than one facility at different service centers. To reduce the complexity of the implementation of the horizontal scalability of the IaaS infrastructures, the use of a technology service oriented infrastructure is recommended to ensure that the interaction between two or more different service centers can be done more simply and easily even though it is likely to involve a wide range of communication technologies and different cloud computing management. This is because the service oriented infrastructure acts as a middle man that translates and processes interactions and protocols of different cloud computing infrastructures without the modification of the complex to ensure horizontal scalability can be run easily and smoothly. This paper presents the potential of using a service-oriented infrastructure framework to enable transparent vertical scalability of cloud computing infrastructures by adapting three projects in this research: SLA@SOI consortium, Open Cloud Computing Interface (OCCI), and OpenStack
Addition of Ag2O in Er3+doped oxyfluorophosphate glass to allow the drawing of optical fibers
Here, Ag2O containing glasses in the NaPO3–CaF2 glass network were prepared using standard melting process. The addition of Ag2O was found to increase the thermal stability of the glass due to the decrease in the Q2 units at the expense of Q1 units, to decrease the intensity of the upconversion under 980 nm pumping and to have a small impact on the nucleation and growth mechanism. Due to the thermal stability against crystallization of the glass prepared with 4 mol % of Ag2O, we demonstrate that fiber can be drawn from this glass. Despite the formation of Ag nanoparticles at the surface of the fiber although the drawing is a fast process, light can still be confined in the fiber. The fiber exhibits a large emission band centered at 1.5 μm under 980 nm pumping.Peer reviewe
Polymer-based technology platform for robust electrochemical sensing using gold microelectrodes
Polymer-based technology platform for robust electrochemical sensing using gold microelectrodes
Notes on the Topology of Analytic Sets (Geometry of Manifolds)
Deep Vein Thrombosis (DVT) and the associated condition of Pulmonary Embolism (PE) are the most common cause of unexpected death in developed nations. DVT is an internal clot formed in one of the body's deep veins, typically in the leg. If a part of the clot breaks free and moves into the lung, it can lead to pulmonary embolism (PE) which is often fatal. D-dimer is a recognised marker for the diagnosis of thrombus and is routinely used by skilled technical staff as part of an ELISA technique in hospital laboratories. Current D-dimer point-of-care tests are not sufficiently quantitative to allow them to be used to exclude DVT/PE. As a consequence, clinicians need to rely on the use of expensive Doppler ultrasound imaging (DUS), creating additional pressure on national health services. The DUS examination can take several days, during which time heparin is required to be administered to the patient. There is increasing in the development of low cost Lab-on-a-chip systems that will allow chemical and biological processing by non-specialist staff. A low cost, easy to use, portable and quantitative device for DVT/PE would be highly desirable since it would provide reliable diagnosis and aid faster treatment and recovery as well as lower healthcare provider costs
Series of Mn Complexes Based on N-Centered Ligands and Superoxide - Reactivity in an Anhydrous Medium and SOD-Like Activity in an Aqueous Medium Correlated to MnII/MnIII Redox Potentials
Two crystal structures are described in this article: (a) the structure of a monomeric MnII complex with the tridentate N-centered N3 ligand tris[(1-methyl-2-imidazolyl)methyl]amine (TMIMA) ([MnII(TMIMA)2]2+); and (b) the structure of a monomeric MnIII complex with the tridentate N-centered N2O ligand 2-{[(1-methyl-2-imidazolyl)methyl]amino}phenolate (PI–)2 ([MnIII(PI)2]+) (5). The latter was isolated both in the MnII and in the MnIII state, although only MnIII crystals were successfully grown. They are part of a series of Mn complexes prepared as SOD mimics, namely [Mn(BMPG)(H2O)]+ (2) {BMPG = N,N-bis[(6-methyl-2-pyridyl)methyl]glycinate}, [Mn(IPG)(MeOH)]+ (3) {IPG = N-[(1-methyl-2-imidazolyl)methyl]-N-(2-pyridylmethyl)glycinate}, [Mn(BIG)(H2O)2]+ (4) {BIG = N,N-bis[(1-methyl-2-imidazolyl)methyl]glycinate}. The reactivity of MnII complexes 1 and 2 in an anhydrous medium is described and compared to that of complexes 3 and 4, the data for which was previously published. The cyclic voltammograms of the whole complex series were recorded in an aqueous medium (collidine buffer). Their SOD-like activities were estimated by the McCord–Fridovich test (IC50 with 22 μM cytc FeIII: 1.6 ± 0.1 μMol L–1 for 1, 1.2 ± 0.5 μmol L–1 for 2, 3.0 ± 0.2 μmol L–1 for 3, 3.7 ± 0.6 μmol L–1 for 4, 0.8 ± 0.1 μmol L–1 for 5). IC50 values were converted into the corresponding kinetic constant kMcCF values. A linear correlation between Ea and log(kMcCF) was obtained, indicating that in this series the conversion to MnIII is probably the rate-limiting step. This is of substantial importance for further Mn–SOD mimic design in this serie
Nanometric Layers for Direct, Signal-On, Selective, and Sensitive Electrochemical Detection of Oligonucleotides Hybridization
Dihydropteridine reductase variation in man and the characid fish ?Cheirodon axelrodi?: Evidence for a dimeric enzyme structure
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