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Roberts O.J.,University of Brighton | Bruce A.M.,University of Brighton | Regan P.H.,University of Surrey | Regan P.H.,National Physics Laboratory | And 5 more authors.
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2014

The design of a fast-timing γ-ray detection array aimed at measuring sub-nanosecond half-lives using LaBr3:Ce scintillation crystals is presented. This array will complement novel and existing charged particle and neutron detector arrays at the low-energy branch of a fragment separator (Super-FRS) to be built within the NuSTAR collaboration as part of the future Facility for Anti-proton and Ion Research (FAIR). The array will be used in conjunction with the Advanced Implantation Detector Array (AIDA), to measure implant-decay correlations. Monte-Carlo simulations have been performed to determine the design of the proposed fast-timing array around a localised implantation point. In particular, simulations were used to determine the full-energy peak efficiencies for single cylindrical, conical and 'hybrid' detector geometries, as well as complete array configurations of 'hybrid' and â̂...1.5 in.×2 in. cylindrical crystals. Timing precision calculations were then used to determine the timing response for each configuration based on its simulated efficiency. An informed decision based on the simulated efficiencies and timing precision calculations allowed the optimum configuration for the array to be determined. © 2014 Elsevier B.V. Source


Rathee D.,Manav Rachna International University | Rangi S.,Manav Rachna International University | Chakarvarti S.K.,Manav Rachna International University | Singh V.R.,National Physics Laboratory | Singh V.R.,PDM Educational Institutions
Health and Technology | Year: 2014

In healthcare domain, Wireless Body Area Network (WBAN) has transpired as a prominent technology which is capable of providing better methods of real time patient health monitoring at hospitals, asylums and even at their homes. In recent times, WBAN has gained great interest and proved one of the most explored technologies by health care facilities because of its vital role and wide range of application in clinical sciences. WBAN involve communication between very small sensor nodes with frequently changing environment, hence lots of issues still need to be addressed. Some of the major issues are Physical layer issues, interoperability & mobility issue, reliability, resource management, usability, Energy consumption and QoS issues. This research paper includes a comprehensive survey of recent trends in WBAN research, provides prospective solutions to some major issues using cognitive approach and a proposed concept of Cognitive Radio based WBAN architecture. Thus a conventional WBAN architecture can be improvised to an adaptive, more reliable and efficient WBAN system using Cognitive based approach. © 2014 IUPESM and Springer-Verlag Berlin Heidelberg. Source


Sochalski-Kolbus L.M.,Oak Ridge National Laboratory | Payzant E.A.,Oak Ridge National Laboratory | Cornwell P.A.,Oak Ridge National Laboratory | Watkins T.R.,Oak Ridge National Laboratory | And 7 more authors.
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science | Year: 2015

Residual stress profiles were mapped using neutron diffraction in two simple prism builds of Inconel 718: one fabricated with electron beam melting (EBM) and the other with direct laser metal sintering. Spatially indexed stress-free cubes were obtained by electrical discharge machining (EDM) equivalent prisms of similar shape. The (311) interplanar spacings from the EDM sectioned sample were compared to the interplanar spacings calculated to fulfill stress and moment balance. We have shown that applying stress and moment balance is a necessary supplement to the measurements for the stress-free cubes with respect to accurate stress calculations in additively manufactured components. In addition, our work has shown that residual stresses in electron beam melted parts are much smaller than that of direct laser metal sintered parts most likely due to the powder preheating step in the EBM process. © 2015, The Minerals, Metals & Materials Society and ASM International (outside the USA). Source


Kaminski Schierle G.S.,University of Cambridge | Van De Linde S.,University of Wurzburg | Erdelyi M.,University of Cambridge | Erdelyi M.,National Physics Laboratory | And 8 more authors.
Journal of the American Chemical Society | Year: 2011

Misfolding and aggregation of peptides and proteins is a characteristic of many neurodegenerative disorders, including Alzheimer's disease (AD). In AD the β-amyloid peptide (Aβ) aggregates to form characteristic fibrillar structures, which are the deposits found as plaques in the brains of patients. We have used direct stochastic optical reconstruction microscopy, dSTORM, to probe the process of in situ Aβ aggregation and the morphology of the ensuing aggregates with a resolution better than 20 nm. We are able to distinguish different types of structures, including oligomeric assemblies and mature fibrils, and observe a number of morphological differences between the species formed in vitro and in vivo, which may be significant in the context of disease. Our data support the recent view that intracellular Aβ could be associated with Aβ pathogenicity in AD, although the major deposits are extracellular, and suggest that this approach will be widely applicable to studies of the molecular mechanisms of protein deposition diseases. © 2011 American Chemical Society. Source


Syed S.N.,University of Edinburgh | Schulze H.,University of Edinburgh | MacDonald D.,University of Edinburgh | Crain J.,University of Edinburgh | And 3 more authors.
Journal of the American Chemical Society | Year: 2013

Hybridization of complementary nucleic acid strands is fundamental to nearly all molecular bioanalytical methods ranging from polymerase chain reaction and DNA biosensors to next generation sequencing. For nucleic acid amplification methods, controlled DNA denaturation and renaturation is particularly essential and achieved by cycling elevated temperatures. Although this is by far the most used technique, the management of rapid temperature changes requires bulky instrumentation and intense power supply. These factors so far precluded the development of true point-of-care tests for molecular diagnostics. To overcome this limitation we explored the possibility of using electrochemical means to control reversible DNA hybridization by using the electroactive intercalator daunomycin (DM). We show that redox-state switching of DM altered its properties from DNA binding to nonbinding, under otherwise constant conditions, and thus altered the thermodynamic stability of duplex DNA. The operational principle was demonstrated using complementary synthetic 20mer and 40mer DNA oligonucleotides. Absorbance-based melting curve analysis revealed significantly higher melting temperatures for DNA in the presence of oxidized compared to chemically reduced DM. This difference was exploited to drive cyclic electrochemically controlled denaturation and renaturation. Analysis with in situ UV-vis and circular dichroism spectroelectrochemistry, as two independent techniques, indicated that up to 80% of the DNA was reversibly hybridized. This remarkable demonstration of electrochemical control of five cycles of DNA denaturation and renaturation, under otherwise constant conditions, could have wide-ranging implications for the future development of miniaturized analytical systems for molecular diagnostics and beyond. © 2013 American Chemical Society. Source

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