9,369 research outputs found

    Intelligent and adaptive tutoring for active learning and training environments

    Get PDF
    Active learning facilitated through interactive and adaptive learning environments differs substantially from traditional instructor-oriented, classroom-based teaching. We present a Web-based e-learning environment that integrates knowledge learning and skills training. How these tools are used most effectively is still an open question. We propose knowledge-level interaction and adaptive feedback and guidance as central features. We discuss these features and evaluate the effectiveness of this Web-based environment, focusing on different aspects of learning behaviour and tool usage. Motivation, acceptance of the approach, learning organisation and actual tool usage are aspects of behaviour that require different evaluation techniques to be used

    Clinical and magnetic resonance imaging characteristics of thoracolumbar intervertenral disk extrusions and protrusions in large breed dogs

    Get PDF
    It has recently been shown that the fat-derived hormone adiponectin has the ability to decrease hyperglycemia and to reverse insulin resistance. However, bacterially produced full-length adiponectin is functionally inactive. Here, we show that endogenous adiponectin secreted by adipocytes is post-translationally modified into eight different isoforms, as shown by two-dimensional gel electrophoresis. Carbohydrate detection revealed that six of the adiponectin isoforms are glycosylated. The glycosylation sites were mapped to several lysines (residues 68, 71, 80, and 104) located in the collagenous domain of adiponectin, each having the surrounding motif of GXKGE(D). These four lysines were found to be hydroxylated and subsequently glycosylated. The glycosides attached to each of these four hydroxylated lysines are possibly glucosylgalactosyl groups. Functional analysis revealed that full-length adiponectin produced by mammalian cells is much more potent than bacterially generated adiponectin in enhancing the ability of subphysiological concentrations of insulin to inhibit gluconeogenesis in primary rat hepatocytes, whereas this insulin-sensitizing ability was significantly attenuated when the four glycosylated lysines were substituted with arginines. These results indicate that full-length adiponectin produced by mammalian cells is functionally active as an insulin sensitizer and that hydroxylation and glycosylation of the four lysines in the collagenous domain might contribute to this activity.link_to_subscribed_fulltex

    Validation and Improvement of the Beef Production Sub-index in Ireland for Beef Cattle

    Get PDF
    End of project reportThe objectives of the following study were to: a. Quantify the effect of sire genetic merit for BCI on: 1. feed intake, growth and carcass traits of progeny managed under bull or steer beef production systems. 2. live animal scores, carcass composition and plasma hormone and metabolite concentrations in their progeny. b. Compare the progeny of : 1. Late-maturing beef with dairy breeds and 2. Charolais (CH), Limousin (LM), Simmental (SM) and Belgian Blue (BB) sires bred to beef suckler dams, for feed intake, blood hormones and metabolites, live animal measurements, carcass traits and carcass value in bull and steer production systems

    Benchmarking calculations of excitonic couplings between bacteriochlorophylls

    Full text link
    Excitonic couplings between (bacterio)chlorophyll molecules are necessary for simulating energy transport in photosynthetic complexes. Many techniques for calculating the couplings are in use, from the simple (but inaccurate) point-dipole approximation to fully quantum-chemical methods. We compared several approximations to determine their range of applicability, noting that the propagation of experimental uncertainties poses a fundamental limit on the achievable accuracy. In particular, the uncertainty in crystallographic coordinates yields an uncertainty of about 20% in the calculated couplings. Because quantum-chemical corrections are smaller than 20% in most biologically relevant cases, their considerable computational cost is rarely justified. We therefore recommend the electrostatic TrEsp method across the entire range of molecular separations and orientations because its cost is minimal and it generally agrees with quantum-chemical calculations to better than the geometric uncertainty. We also caution against computationally optimizing a crystal structure before calculating couplings, as it can lead to large, uncontrollable errors. Understanding the unavoidable uncertainties can guard against striving for unrealistic precision; at the same time, detailed benchmarks can allow important qualitative questions--which do not depend on the precise values of the simulation parameters--to be addressed with greater confidence about the conclusions

    Prohibition of e-cigarettes in the US: Are prohibitions where alcohol is consumed related to lower alcohol consumption?

    Get PDF
    Recently, research has suggested negative consequences related to electronic cigarette (e-cig) use, including the increased risk for alcohol use and abuse. Previous work found that cigarette smoking ban legislation lowered overall smoking and alcohol use rates; however, researchers have not yet examined the potential effects of prohibiting e-cig use. The present study surveyed 617 individuals from a community-based online sample in the US (mean age = 33.33, SD = 10.50, 54.7 per cent female) who reported their smoking/e-cig use status, alcohol consumption, and the presence of e-cig prohibitions where they consume alcohol. E-cig prohibition was associated with a lower likelihood of being an e-cig user (OR = 0.12, p < 0.001) or dual user (use both cigarettes and e-cigs) (OR = 0.07, p < 0.001). Alcohol Use Disorder Identification Test scores (b = -1.92, p < 0.001), total drinks consumed over 14 days (b = -4.58, p = 0.002), and average drinks per drinking day (b = -0.71, p < 0.001) were all lower when e-cigs were prohibited. Findings are an initial step in this line of research and suggest important future work examining implications of e-cig prohibition recommendations and policy

    Is Hot IT a False Economy? An Analysis of Server and Data Center Energy Efficiency as Temperatures Rise

    Get PDF
    As demand for digital services grows, there is need to improve efficiency and reduce the environmental impact of data centers. The largest energy consumer in any data center is the IT, followed by the systems dedicated to cooling. Aiming to improve efficiency, and driven by metrics like PUE, there is a trend towards running data centers hotter to reduce the cooling energy. There is little research investigating the effect this will have on the IT beyond failure rates. To ensure overall efficiency is improving, we must view the data center as a system of systems, taking a holistic view rather than focusing on individual sub-systems. In this paper we use industry standard benchmarks and a wind-tunnel to profile typical enterprise IT. We analyze the effect of environmental conditions on IT efficiency, showing minor increases in temperature or pressure impact the efficiency of servers. Using an idealized, simulated data center case study we show that the interaction between cooling systems, server behaviour and local climate are non-trivial and increasing temperatures has potential to worsen efficiency

    Combined expectancies of alcohol and e-cigarette use relate to higher alcohol use

    Get PDF
    Electronic cigarettes (e-cigs) were created to approximate the look, feel, and experience of using a cigarette. Since cigarette and alcohol use co-occur, we hypothesized that e-cig and alcohol use also co-occur, likely due to shared positive drug expectations. Using self-report data from two independent samples of community-dwelling alcohol using adults, the present study: (1) modified the Nicotine and Other Substance Interaction Expectancy Questionnaire (NOSIE) to assess expectancies of combined e-cig and alcohol use (i.e. the individuals perceived likelihood of using e-cigs and alcohol together; NOSIE-ER); and (2) examined the relationships among e-cig use, expectancies, and alcohol use across e-cig use status. In the first sample (N=692, mean age=32.6, SD=9.74, 50.7% female, 82.2% Caucasian), exploratory factor analysis suggested the presence of two factors: (1) alcohol use leads to e-cig use (Scale 1; α=0.85); and (2) e-cig use leads to alcohol use (Scale 2; α=0.91). In the second sample (N=714, mean age=34.1, SD=10.89, 47.8% female, 75.6% Caucasian), confirmatory factor analysis supported this factor structure (χ(2)=47.00, p<0.01, df=19; RMSEA=0.08, 90% CI=0.05-0.11; TLI=0.99; CFI=0.99). Compared to non e-cig users, e-cig users had significantly higher problematic alcohol use in both samples (b's=0.09 to 0.14, p's<.05). Expectancies of combined e-cig and alcohol use were significantly related to problematic alcohol use (b's=-0.92 to 0.26, p's<.05). In sum, e-cig use is related to alcohol use and expectancies of combined e-cig and alcohol use; consequently, reshaping of beliefs about needs or desires to co-use could be a prime point of intervention
    • 

    corecore