178 research outputs found
IT security certifications : stakeholder evaluation and selection
Information technology (IT) security certifications have proliferated in recent years. However they differ in regards to stakeholder considerations of credibility, accessibility and relevance. Key stakeholders with an interest in selecting an IT security certification (IT security professionals, employers, governments and higher education institutes) lack a systematic approach for differentiating between candidate certifications and selecting the “best” certification to satisfy requirements. The paper focuses on reporting a confirmatory focus group from a recent research project. It provides a framework for supporting stakeholder evaluation and selection of IT security certifications and discusses key implications for the IT security industry, IT security certifications, and the higher education sector.<br /
A tool for assessing error in digital elevation models from a user’s perspective
A Digital Elevation Model (DEM) is a representation of geographic reality. The
elevations recorded within DEMs have been shown to contain errors pertaining to
sampling, measurement and interpolation (Fisher, 1998). Even a small amount of
elevation error can greatly affect derivative products (Holmes et al., 2000). This can
potentially have a significant impact on the application of DEMs in Geographical
Information Systems (GIS) where first and
second order derivatives are considered
Multi-Scale Entropy Analysis as a Method for Time-Series Analysis of Climate Data
Evidence is mounting that the temporal dynamics of the climate system are changing at the same time as the average global temperature is increasing due to multiple climate forcings. A large number of extreme weather events such as prolonged cold spells, heatwaves, droughts and floods have been recorded around the world in the past 10 years. Such changes in the temporal scaling behaviour of climate time-series data can be difficult to detect. While there are easy and direct ways of analysing climate data by calculating the means and variances for different levels of temporal aggregation, these methods can miss more subtle changes in their dynamics. This paper describes multi-scale entropy (MSE) analysis as a tool to study climate time-series data and to identify temporal scales of variability and their change over time in climate time-series. MSE estimates the sample entropy of the time-series after coarse-graining at different temporal scales. An application of MSE to Central European, variance-adjusted, mean monthly air temperature anomalies (CRUTEM4v) is provided. The results show that the temporal scales of the current climate (1960–2014) are different from the long-term average (1850–1960). For temporal scale factors longer than 12 months, the sample entropy increased markedly compared to the long-term record. Such an increase can be explained by systems theory with greater complexity in the regional temperature data. From 1961 the patterns of monthly air temperatures are less regular at time-scales greater than 12 months than in the earlier time period. This finding suggests that, at these inter-annual time scales, the temperature variability has become less predictable than in the past. It is possible that climate system feedbacks are expressed in altered temporal scales of the European temperature time-series data. A comparison with the variance and Shannon entropy shows that MSE analysis can provide additional information on the statistical properties of climate time-series data that can go undetected using traditional method
Keep Your Stats in the Cloud! Evaluating the Use of Google Sheets to Teach Quantitative Methods
Teaching quantitative methods at the undergraduate level is a difficult yet rewarding endeavor due to the challenges instructors face in presenting the material. One way to bolster student learning is through the use of statistical software packages. Google Sheets is a cloud-based spreadsheet program capable of many basic statistical procedures, which has yet to be evaluated for use in quantitative methods courses. This article contains pros and cons to using Google Sheets in the classroom and provides an evaluation of student attitudes toward using Google Sheets in an introductory quantitative methods class. The results suggest favorable student attitudes toward Google Sheets and which attitudes toward Google Sheets show a positive relationship with quantitative self-efficacy. Thus, based on the positive student attitudes and the unique features of Google Sheets, it is a viable program to use in introductory methods classes. However, due to limited functionality, Google Sheets may not be useful for more advanced courses. Future research may want to evaluate the use of third-party Google Sheets applications, which can increase functionality, and the use of Google Sheets in online classes
Atmospheric mercury and fine particulate matter in coastal New England : implications for mercury and trace element sources in the northeastern United States
This paper is not subject to U.S. copyright. The definitive version was published in Atmospheric Environment 79 (2013): 760–768, doi:10.1016/j.atmosenv.2013.07.031.Intensive sampling of ambient atmospheric fine particulate matter was conducted at Woods Hole, Massachusetts over a four-month period from 3 April to 29 July, 2008, in conjunction with year-long deployment of the USGS Mobile Mercury Lab. Results were obtained for trace elements in fine particulate matter concurrently with determination of ambient atmospheric mercury speciation and concentrations of ancillary gasses (SO2, NOx, and O3). For particulate matter, trace element enrichment factors greater than 10 relative to crustal background values were found for As, Bi, Cd, Cu, Hg, Pb, Sb, V, and Zn, indicating contribution of these elements by anthropogenic sources. For other elements, enrichments are consistent with natural marine (Na, Ca, Mg, Sr) or crustal (Ba, Ce, Co, Cs, Fe, Ga, La, Rb, Sc, Th, Ti, U, Y) sources, respectively. Positive matrix factorization was used together with concentration weighted air-mass back trajectories to better define element sources and their locations. Our analysis, based on events exhibiting the 10% highest PM2.5 contributions for each source category, identifies coal-fired power stations concentrated in the U.S. Ohio Valley, metal smelting in eastern Canada, and marine and crustal sources showing surprisingly similar back trajectories, at times each sampling Atlantic coastal airsheds. This pattern is consistent with contribution of Saharan dust by a summer maximum at the latitude of Florida and northward transport up the Atlantic Coast by clockwise circulation of the summer Bermuda High. Results for mercury speciation show diurnal production of RGM by photochemical oxidation of Hg° in a marine environment, and periodic traverse of the study area by correlated RGM-SO2(NOx) plumes, indicative of coal combustion sources.We acknowledge support of the USGS Toxic Substances Hydrology
Program, the USGS Energy Resources Program, the National
Science Foundation Small Grants for Exploratory Research Program,
and for initial support, the USGS Mendenhall Postdoctoral Program
Structural properties of mobile armors formed at different flow strengths in gravel-bed rivers
Differences in the structure of mobile armors formed at three different flow strengths have been investigated in a laboratory flume. The temporal evolution of the bed surfaces and the properties of the final beds were compared using metrics of surface grain size, microtopography, and bed organization at both grain and mesoscales. Measurements of the bed condition were obtained on nine occasions during each experiment to describe the temporal evolution of the beds. Structured mobile armors formed quickly in each experiment. At the grain scale (1–45 mm; 9 ≤ Ds50 ≤ 17 mm where Ds50 is the median surface particle size), surface complexity decreased and bed roughness increased in response to surface coarsening and the development of the mobile armor. Particles comprising the armor also became flow aligned and developed imbrication. At a larger scale (100–200 mm), the surface developed a mesoscale topography through the development of bed patches with lower and higher elevations. Metrics of mobile armor structure showed remarkable consistency over prolonged periods of near-constant transport, demonstrating for the first time that actively transporting surfaces maintain an equilibrium bed structure. Bed structuring was least developed in the experiments conducted at the lowest flow strength. However, little difference was observed in the structural metrics of the mobile armors generated at higher flows. Although the range of transport rates studied was limited, the results suggest that the structure of mobile armors is insensitive to the formative transport rate except when rates are low (τ* ≈ 0.03 where τ* is the dimensionless shear stress)
Pneumococcal within-host diversity during colonization, transmission and treatment
Characterizing the genetic diversity of pathogens within the host promises to greatly improve surveillance and reconstruction of transmission chains. For bacteria, it also informs our understanding of inter-strain competition and how this shapes the distribution of resistant and sensitive bacteria. Here we study the genetic diversity of Streptococcus pneumoniae within 468 infants and 145 of their mothers by deep sequencing whole pneumococcal populations from 3,761 longitudinal nasopharyngeal samples. We demonstrate that deep sequencing has unsurpassed sensitivity for detecting multiple colonization, doubling the rate at which highly invasive serotype 1 bacteria were detected in carriage compared with gold-standard methods. The greater resolution identified an elevated rate of transmission from mothers to their children in the first year of the child's life. Comprehensive treatment data demonstrated that infants were at an elevated risk of both the acquisition and persistent colonization of a multidrug-resistant bacterium following antimicrobial treatment. Some alleles were enriched after antimicrobial treatment, suggesting that they aided persistence, but generally purifying selection dominated within-host evolution. Rates of co-colonization imply that in the absence of treatment, susceptible lineages outcompeted resistant lineages within the host. These results demonstrate the many benefits of deep sequencing for the genomic surveillance of bacterial pathogens. Longitudinal population deep sequencing of Streptococcus pneumoniae sampled from infants and their mothers improves our understanding of the dynamics of colonization, transmission, inter-strain competition and the impact of antibiotic treatment.Peer reviewe
"A different world" exploring and understanding the climate of a recently re-rolled sexual offender prison
Understanding how sexual offenders experience prison and its environment is important because such experiences can impact on rehabilitation outcomes. The purpose of this research investigation was to explore the rehabilitative and therapeutic climate of a recently re-rolled sexual offender prison. The research took a mixed methods approach and consisted of quantitative and qualitative phases. There were differences between prisoners and staff on their perception of the prison climate and for prisoner and staff relationships. The qualitative results helped to explain the quantitative findings and added a more nuanced understanding of the experience of the prison, the nature of prisoner and staff relationships and the opportunities for personal growth within the prison. The study has important implications for prisons that co-locate sexual offenders and want to provide an environment conducive to rehabilitation
Toll-like receptor 3 activation impairs excitability and synaptic activity via TRIF signalling in immature rat and human neurons
Toll like receptor 3 (TLR3) belongs to a family of pattern recognition receptors that recognise molecules found on pathogens referred to as pathogen associated molecular patterns (PAMPs). Its involvement in innate immunity is well known but despite its presence in the central nervous system (CNS), our knowledge of its function is limited. Here, we have investigated whether TLR3 activation modulates synaptic activity in primary hippocampal cultures and induced pluripotent stem cell (iPSC)-derived neurons. Synaptically driven spontaneous action potential (AP) firing was significantly reduced by the TLR3 specific activator, poly I:C, in a concentration-dependent manner following both short (5 min) and long exposures (1h) in rat hippocampal cultures. Notably, the consequence of TLR3 activation on neuronal function was reproduced in iPSC-derived cortical neurons, with poly I:C (25µg/ml, 1h) significantly inhibiting sAP firing. We examined the mechanisms underlying these effects, with poly I:C significantly reducing peak sodium current, an effect dependent on the MyD88-independent TRIF dependent pathway. Furthermore, poly I:C (25µg/ml, 1h) resulted in a significant reduction in miniature excitatory postsynaptic potential (mEPSC) frequency and amplitude and significantly reduced surface AMPAR expression. These novel findings reveal that TLR3 activation inhibits neuronal excitability and synaptic activity through multiple mechanisms, with this being observed in both rat and human iPSC-derived neurons. These data might provide further insight into how TLR3 activation may contribute to neurodevelopmental disorders following maternal infection and in patients with increased susceptibility to herpes simplex encephalitis
Ungentlemanly Capitalism: John Hay and Malaya, 1904-1964
John Hay was one of Britain’s leading colonial capitalists, building his career from the 1900s to the 1960s in Malaya’s plantation industry. He became the leading spokesperson for the British rubber growers, and played a major role in the formulation of international restriction schemes during the 1930s. Hay was a remarkable entrepreneurial talent, consolidating his corporate power through the premiere Malayan agency house, Guthrie & Co. This in itself challenges the notion that Britain’s myriad of ‘free-standing’ companies, which were typical of direct investment in the Empire, represented a relatively weak and unsustainable form of multinational enterprise. But Hay’s dominance of the Malayan plantation sector also questions the notion of ‘gentlemanly capitalism’ as the driving force behind the expansion and sustenance of the British imperial system. Hay’s network of colonial corporate influence did not extend into the corridors of ‘gentlemanly capitalist’ power in Whitehall and the City, where he often had frosty relations. Ultimately, it was the financial sector in London that brought about Hay’s forced resignation from Guthrie in 1963. Examining questions of class, ethnicity, personality, ideology and strategy, the article focuses on why Hay did not develop better relations with commercial, financial and official elites, issues that would also engender tensions with the post-colonial political and business leadership of Malaya/Malaysia
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