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Clustering and networking among small independent hotels: developments over ten years
This paper reports on networking activities amongst a cluster of independent hotels with a view to analysing key variables in network development for SMEs. A comparative, longitudinal element is introduced by reference to an earlier study of the same phenomenon, ten years earlier. Of particular interest is the influence of various forms of social capital in the development of informal networks and the inter-play between co-operation and competition over time. Given the time gap between the two studies, the effect of sectoral changes on network development is also examined. The research revisits and extends a previous study of many of the same hotels which were investigated in 1995 over their formal and informal links that were found to be influenced by such factors across two classifications - the business as unit (proximity, perceptions of quality) and the individual respondent (personal social networks and ethnicity). Extending that analysis, social capital concepts and relevant references to embedded networks and kinship groups and co-operative game rules will be introduced in this paper.
A highly concentrated population of small, independent hotels in Central London had been identified in the previous research project and it is from this sample that the current research drew and extended its own sample of hotels. With such a high number of hotels in the area a mixture of ‘snowball’ sampling and self-selection was successfully employed. Of the original 29 hotels, 22 have been re-interviewed and complemented by another 19. Of the remainder of the original sample, several had subsequently merged or failed to survive the intervening period. Face-to-face interviews were conducted with owner-managers in all cases using a structured questionnaire that replicated as much as possible of the original questionnaire, with both open and closed questions to allow some individual expression on relevant topics. The quantitative data obtained will be analysed using UCINET software to generate visual representations of networks alongside statistical and cluster analyses.
Both academic and policy implications are likely to arise from this research, such as novel insights from such an unique periodic comparison of networks development, the influence of social capital on (formal and informal) network activities and the changing influence and consolidation of hotel groups through mergers and franchising
Shaping plasmon beams via the controlled illumination of finite-size plasmonic crystals
Plasmonic crystals provide many passive and active optical functionalities, including enhanced sensing, optical nonlinearities, light extraction from LEDs and coupling to and from subwavelength waveguides. Here we study, both experimentally and numerically, the coherent control of SPP beam excitation in finite size plasmonic crystals under focussed illumination. The correct combination of the illuminating spot size, its position relative to the plasmonic crystal, wavelength and polarisation enables the efficient shaping and directionality of SPP beam launching. We show that under strongly focussed illumination, the illuminated part of the crystal acts as an antenna, launching surface plasmon waves which are subsequently filtered by the surrounding periodic lattice. Changing the illumination conditions provides rich opportunities to engineer the SPP emission pattern. This offers an alternative technique to actively modulate and control plasmonic signals, either via micro- and nano-electromechanical switches or with electro- and all-optical beam steering which have direct implications for the development of new integrated nanophotonic devices, such as plasmonic couplers and switches and on-chip signal demultiplexing. This approach can be generalised to all kinds of surface waves, either for the coupling and discrimination of light in planar dielectric waveguides or the generation and control of non-diffractive SPP beams
IRD dropout study
This final report describes work performed by SRS Technologies for the NASA Marshall Space Flight Center under Contract NAS8-39077, entitled 'Integrated Receiver-Decoder Dropout Study'. The purpose of the study was to determine causes of signal fading effects on ultra-high-frequency (UHF) range safety transmissions to the Space Shuttle during flyout. Of particular interest were deep fades observed at the External Tank (ET) Integrated Receiver-Decoder (IRD) during the flyout interval between solid rocket booster separation and ET separation. Analytical and simulation methods were employed in this study to assess observations captured in flight telemetry data records. Conclusions based on the study are presented in this report, and recommendations are given for future experimental validation of the results
Retardation of atherosclerosis in immunocompetent apolipoprotein (apo) E-deficient mice followingliver-directed administration of a [E1-, E3-,polymerase-] adenovirus vector containing the elongation factor-1a promoter driving expression of human apoE cDNA
Although gene transfer of human apolipoprotein E (apoE), a 34-kDa circulating glycoprotein, to the liver of apoEdeficient(apoE-/-) mice using recombinant adenoviral vectors (rAd) is antiatherogenic, its full therapeutic potentialhas yet to be realized. First generation vectors led to immune clearance of transduced hepatocytes, while animproved vector with adenovirus regions E1, E3 and DNA polymerase deleted also had transient effects due tocellular shutdown of the cytomegalovirus (CMV) promoter. Here, we have studied an alternative promoter from thecellular elongation factor 1a (EF-1a) gene, injecting 6-8 week old apoE-/- mice intravenously with 2x1010 virusparticles (vp) of the [E1-, E3-, polymerase-] rAd vector Ad-EF1·-apoE. Plasma apoE levels were low (18-55 ng/ml)and failed to reduce plasma cholesterol or normalize the adverse lipoprotein profile. By contrast, thehyperlipidaemic phenotype of apoE-/- mice treated with Ad-CMV-apoE (2x1010 vp) was transiently normalized.Nevertheless, at termination (265 days) the aortic lesion areas in animals given Ad-EF1·-apoE were significantlyreduced by 15% (P<0.05) compared to untreated animals, a decrease approaching that in Ad-CMV-apoE-treatedmice (23%; P<0.02). Importantly, the attenuation of apoE transgene expression noted with the CMV promoter wasabsent with the EF-1a promoter, which gave relatively sustained, albeit low, levels of plasma apoE throughout thestudy period
Niemann-Pick Type C Disease Reveals a Link between Lysosomal Cholesterol and PtdIns(4,5)P2 That Regulates Neuronal Excitability.
There is increasing evidence that the lysosome is involved in the pathogenesis of a variety of neurodegenerative disorders. Thus, mechanisms that link lysosome dysfunction to the disruption of neuronal homeostasis offer opportunities to understand the molecular underpinnings of neurodegeneration and potentially identify specific therapeutic targets. Here, using a monogenic neurodegenerative disorder, NPC1 disease, we demonstrate that reduced cholesterol efflux from lysosomes aberrantly modifies neuronal firing patterns. The molecular mechanism linking alterations in lysosomal cholesterol egress to intrinsic tuning of neuronal excitability is a transcriptionally mediated upregulation of the ABCA1 transporter, whose PtdIns(4,5)P2-floppase activity decreases plasma membrane PtdIns(4,5)P2. The consequence of reduced PtdIns(4,5)P2 is a parallel decrease in a key regulator of neuronal excitability, the voltage-gated KCNQ2/3 potassium channel, which leads to hyperexcitability in NPC1 disease neurons. Thus, cholesterol efflux from lysosomes regulates PtdIns(4,5)P2 to shape the electrical and functional identity of the plasma membrane of neurons in health and disease
What are the benefits of the International Baccalaureate Middle Years Programme for teaching and learning? Perspectives from stakeholders in Australia
The report was commissioned by the IB and builds on existing studies on the Middle Years Program. It is the first study to comprehensively examine key ‘insider’ stakeholder perspectives of the benefits of the MYP for teaching and learning in Australia. Specifically it examines the perspectives of seventeen MYP teachers, five MYP Coordinators and six school principals from three public and two private schools, and four representatives from governing bodies and public education authorities. A qualitative research design involving case studies, semi-structured interviews and document analysis was used to gather rich data about insiders’ and key stakeholders’ perspectives of the impact of MYP on teaching and learning addressing the following research questions: 1) What are the impediments and enablers of offering the MYP? 2) What are the benefits of the MYP for teaching and learning? 3) What are the challenges of the MYP for teaching and learning
Boundary effects in finite size plasmonic crystals: Focusing and routing of plasmonic beams for optical communications
Plasmonic crystals, which consist of periodic arrangements of surface features at a metal-dielectric interface, allow the manipulation of optical information in the form of surface plasmon polaritons. Here we investigate the excitation and propagation of plasmonic beams in and around finite size plasmonic crystals at telecom wavelengths, highlighting the effects of the crystal boundary shape and illumination conditions. Significant differences in broad plasmonic beam generation by crystals of different shapes are demonstrated, while for narrow beams, the propagation onto the smooth metal film is less sensitive to the crystal boundary shape. We show that by controlling the boundary shape, the size and the excitation beam parameters, directional control of propagating plasmonic modes and associated beam parameters such as angular beam splitting, focusing power and beam width can be efficiently achieved. This provides a promising route for robust and alignment-independent integration of plasmonic crystals with optical communication components
The effect of flight line spacing on radioactivity inventory and spatial feature characteristics of airborne gamma-ray spectrometry data
Airborne Gamma Spectrometry (AGS) is well suited to the mapping of radioactivity in the environment. Flight parameters (e.g. speed and line spacing) directly affect the rate of area coverage, cost, and data quality of any survey. The influences of line spacing have been investigated for data from inter‐tidal, coastal and upland environments with a range of <sup>137</sup>Cs activity concentrations and depositional histories. Estimates of the integrated <sup>137</sup>Cs activity (‘inventory’) within specified areas and the shapes of depositional features were calculated for subsets of the data at different line spacings. Features with dimensions greater than the line spacing show variations in inventory and area of less than 3%, and features with dimensions less than the line spacing show larger variations and a decreased probability of detection. The choice of line spacing for a task is dependent on the dimensions of the features of interest and required edge definition. Options for line spacing for different tasks are suggested. It is noted that for regional mapping, even 5–10 km line spacing can produce useful data
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