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Multiwavelength observations of the TeV binary LS I+ 61 degrees 303 with VERITAS, Fermi-LAT, and Swift/XRT during a TeV outburst
Get PDFWe present the results of a multiwavelength observational campaign on the TeV binary system LS I +61° 303 with the VERITAS telescope array (\u3e200 GeV), Fermi-LAT (0.3-300 GeV), and Swift/XRT (2-10 keV). The data were taken from 2011 December through 2012 January and show a strong detection in all three wavebands. During this period VERITAS obtained 24.9 hr of quality selected livetime data in which LS I +61° 303 was detected at a statistical significance of 11.9σ. These TeV observations show evidence for nightly variability in the TeV regime at a post-trial significance of 3.6σ. The combination of the simultaneously obtained TeV and X-ray fluxes do not demonstrate any evidence for a correlation between emission in the two bands. For the first time since the launch of the Fermi satellite in 2008, this TeV detection allows the construction of a detailed MeV-TeV spectral energy distribution from LS I +61° 303. This spectrum shows a distinct cutoff in emission near 4 GeV, with emission seen by the VERITAS observations following a simple power-law above 200 GeV. This feature in the spectrum of LS I +61° 303, obtained from overlapping observations with Fermi-LAT and VERITAS, may indicate that there are two distinct populations of accelerated particles producing the GeV and TeV emission
A search for enhanced very high energy gamma-ray emission from the 2013 march crab nebula flare
Get PDFIn 2013 March, a flaring episode from the Crab Nebula lasting ~2 weeks was detected by Fermi-LAT (Large Area Telescope on board the Fermi Gamma-ray Space Telescope). The Very Energetic Radiation Imaging Telescope Array System (VERITAS) provides simultaneous observations throughout this period. During the flare, Fermi-LAT detected a 20 fold increase in flux above the average synchrotron flux \u3e100 MeV seen from the Crab Nebula. Simultaneous measurements with VERITAS are consistent with the non-variable long-term average Crab Nebula flux at TeV energies. Assuming a linear correlation between the very high energy flux change \u3e1 TeV and the flux change seen in the Fermi-LAT band \u3e100 MeV during the period of simultaneous observations, the linear correlation factor can be constrained to be at most 8.6 × 10–3 with 95% confidence
Critical Success Factors in the Promotion of Sustainable Rural Tourism by Destination Marketing Organisations: A Study of Ballyhoura Fáilte
Get PDFWith the Irish tourism industry maturing, destination marketing organisations (DMOs) must meet tourists’ changing expectations. For rural tourism destinations, the challenge lies in ensuring that they obtain a position of sustainability in the Irish tourism industry (Department of Arts, Heritage and Gaeltacht, 2011). Due to the highly volatile nature of the Irish rural tourism industry, treating rural tourism like any other product does not comply with the new approach to destination marketing management, which considers the resources available, the environment, the tourist, and the residents themselves (Buhalis, 2000; Pike, 2008). The aim of this study is to carry out a comprehensive review of extant literature to identify the critical success factors in destination marketing management and assess how these success factors compare with the practice of destination marketing management by a small rural destination management organisation (DMO) in Ireland, namely Ballyhoura Fáilte. The paper finds that Ballyhoura Fáilte has been largely successful in identifying and carrying out the CSF activities that are vital to drive strategy and ensure sustainable competitive advantage. This paper also proposes a full set of Critical Success Factors (CSFs), or essential tasks, important for ensuring the long-term success of DMOs
Developing the External Engagement Process in Higher Education through Effective Change and Technology
Get PDFEngagement with external organisations and enterprises is increasingly part of the higher education mission and the contribution of universities to local and regional economic and social development remains an important, but difficult to evidence, metric for Higher Education Institutions (HEI). This paper explores the implementation of a Customer Relationship Management (CRM) system to support external engagement and to build business intelligence in one higher education institution in Ireland. Building on the findings of the Roadmap for Employment-Academic Partnership (REAP) project, through a structured process towards a professional case management approach to interactions this project focuses on the introduction of a CRM system in Cork Institute of Technology (CIT) as a supporting and reporting mechanism which allows the collation of information on current and previous interactions with external organisations. When in place, the system will provide the HEI with a full overview of the current interactions at any point in time with an external organisation as well as providing valuable information to the strategic planning process. The work reported on in this paper and the work of the REAP project generally, was supported by the Higher Education Authority (HEA) under the Strategic Innovation Fund (SIF)
Measurement of the Effect of Policy Changes on Volatility in Dairy Markets1
Get PDFVolatility in dairy commodity markets has become a major concern for many in the dairy supply chain and is likely to remain so in the future. Changes to the Common Agricultural Policy (CAP) over the past decade have more closely aligned EU and World prices and their associated volatilities. The aim of this paper is to measure volatility at farm level in Ireland over time, identify possible reasons for the increased volatility and identify ways of reducing volatility. Statistical measures such as coefficient of variation (CV) and annualised standard deviation are used to provide measures of past volatility and its evolution over time. Family Farm Income (FFI) data, input data and farm gate milk prices are used to highlight historical farm level volatility. As farm level prices should be based on dairy commodity returns, the links between these prices and the farm gate prices are explored. Monthly wholesale prices for Skim Milk Powder (SMP), whole milk powder (WMP), and butter between January 1997 and March 2012 are used for this analysis. The time period is divided into two sub periods to quantify changes in volatility pre and post the Luxembourg Agreement. The results highlight that both commodity price and farm gate volatility has increased dramatically post 2007. Volatility will become a more inherent part of the dairy industry as policy changes cause prices to become further aligned with world prices. The findings of this research highlight that risk management strategies are desirable for the long term success of the dairy industry
Functional Environmental Screening of a Metagenomic Library Identifies stlA; A Unique Salt Tolerance Locus from the Human Gut Microbiome
Get PDFFunctional environmental screening of metagenomic libraries is a powerful means to identify and assign function to novel genes and their encoded proteins without any prior sequence knowledge. In the current study we describe the identification and subsequent analysis of a salt-tolerant clone from a human gut metagenomic library. Following transposon mutagenesis we identified an unknown gene (stlA, for “salt tolerance locus A”) with no current known homologues in the databases. Subsequent cloning and expression in Escherichia coli MKH13 revealed that stlA confers a salt tolerance phenotype in its surrogate host. Furthermore, a detailed in silico analysis was also conducted to gain additional information on the properties of the encoded StlA protein. The stlA gene is rare when searched against human metagenome datasets such as MetaHit and the Human Microbiome Project and represents a novel and unique salt tolerance determinant which appears to be found exclusively in the human gut environment
Discovery Of Tev Gamma-Ray Emission From Cta 1 By Veritas
Get PDFWe report the discovery of TeV gamma-ray emission coincident with the shell-type radio supernova remnant (SNR) CTA 1 using the VERITAS gamma-ray observatory. The source, VER J0006+729, was detected as a 6.5 standard deviation excess over background and shows an extended morphology, approximated by a two-dimensional Gaussian of semimajor (semiminor) axis 0fdg30 (0fdg24) and a centroid 5\u27 from the Fermi gamma-ray pulsar PSR J0007+7303 and its X-ray pulsar wind nebula (PWN). The photon spectrum is well described by a power-law dN/dE = N 0(E/3 TeV)–Γ, with a differential spectral index of Γ = 2.2 ± 0.2stat ± 0.3sys, and normalization N 0 = (9.1 ± 1.3stat ± 1.7sys) × 10–14 cm–2 s–1 TeV–1. The integral flux, F γ = 4.0 × 10–12 erg cm–2 s–1 above 1 TeV, corresponds to 0.2% of the pulsar spin-down power at 1.4 kpc. The energetics, colocation with the SNR, and the relatively small extent of the TeV emission strongly argue for the PWN origin of the TeV photons. We consider the origin of the TeV emission in CTA 1
Teleworking: An Examination of the Irish Dichotomy
Get PDFChanging demographics and labour market structures are placing increased pressure on identifying work/life balance solutions, while global competition is forcing companies to look beyond traditional solutions to search for competitive advantage. Recent rapid technology developments facilitate a strategic application of teleworking, which, in suitable organisations, would appear to alleviate both of these issues. Despite this, the limited evidence that exists in the telework literature indicates a dearth of telework in Irish companies, and recent research on the reasons for this, form a gap in the literature.
This study, empirically examines the key factors that influence the extent of telework in Ireland. Qualitative data has been gathered from thirteen semi-structured (eleven face-to-face) interviews with a combination of current and part-time teleworkers and managers. The exploratory approach employed, provides the opportunity to gain an invaluable perspective from participants with personal experience of working from home. The data gathered during this current study, offers some unique insights into teleworking in Ireland and highlights challenges which appear to be particular to the Irish context. While telework is seen in a positive light, by the respondents in this study, socio-cultural barriers to telework are identified. A recurring theme, emerging from this research, highlights the pervasiveness of a traditional management style, and an Irish culture of mistrust, which poses a particular challenge to those wishing to engage in telework. This current research also reveals a particular Irish need for social affiliation, through workplace interactions, which may account for the prevalence of ‘part-time’ teleworking in Ireland.
Given the attitudinal challenges to telework within Irish organisations, the research findings suggest that there would be clear merit in piloting telework initiatives with carefully selected candidates. Multinationals and young dynamic businesses which remain open to innovative work practices, particularly in the services and technology sectors, are ideally positioned for such an initiative. Coupled with the extension of broadband, a successful outcome, with government sponsored PR, could pave the way for expanding the practice of teleworking in Ireland. This research would be of particular benefit to organisations and individuals considering the option of telework in the future
Crystallization Of The CHAP Domain Of The Endolysin From Staphylococcus Aureus Bacteriophage K
Get PDFCHAPK is the N-terminal cysteine, histidine-dependent amidohydrolase/peptidase domain (CHAP domain) of the Staphylococcus aureus bacteriophage K endolysin LysK. It is formed from the first 165 residues of LysK and functions by cleaving specific peptidoglycan peptide bonds, causing bacterial lysis. CHAPK can lyse S. aureus when applied exogenously, making it a good candidate for the treatment of multidrug-resistant Staphylococcus aureus infections. Here, the crystallization of CHAPK and the collection of native and derivative data to high resolution, which allowed structure solution, are reported. The structure may help to elucidate the mechanism of action and in the design of chimeric proteins or mutants with improved antibacterial activity
VERITAS Observations of the Microquasar Cygnus X-3
Get PDFWe report results from TeV gamma-ray observations of the microquasar Cygnus X-3. The observations were made with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) over a time period from 2007 June 11 to 2011 November 28. VERITAS is most sensitive to gamma rays at energies between 85 GeV and 30 TeV. The effective exposure time amounts to a total of about 44 hr, with the observations covering six distinct radio/X-ray states of the object. No significant TeV gamma-ray emission was detected in any of the states, nor with all observations combined. The lack of a positive signal, especially in the states where GeV gamma rays were detected, places constraints on TeV gamma-ray production in Cygnus X-3. We discuss the implications of the results