14,374 research outputs found

    Coexistence of Antiferromagnetism and Superconductivity in Electron-doped High-Tc Superconductors

    Full text link
    We present magnetotransport evidence for antiferromagnetism in films of the electron-doped cuprates Pr2−x_{2-x}Cex_xCuO4_4. Our results show clear signature of static antiferromagnetism up to optimal doping x=0.15, with a quantum phase transition close to x=0.16, and a coexistence of static antiferromagnetism and superconductivity for 0.12≤\lex≤\le0.15

    An examination of the effects of self-regulatory focus on the perception of the media richness: the case of email

    Get PDF
    Communication is a key element in organizations’ business success. The media richness theory and the channel expansion theory are two of the most influential theories regarding the selection and use of communication media in organizations; however, literature has focused little on the effects of self-regulation by managers and employees in these theories. To analyze these topics, this study develops an empirical investigation by gathering data from 600 managers and employees using a questionnaire. The results suggest that the perception of media richness is positively affected when the individual shows a promotion focus or strategy.Peer ReviewedPostprint (author’s final draft

    An Annotated Bibliography: Published Articles (1861-1998) About the Wild Mammals of South Dakota

    Get PDF
    Our goal in compiling this bibliography was to locate every published article with a connection to any wild South Dakota mammal. However, we understood from the start that this goal would be unattainable. Consequently, this collection can provide only a point of origin to readers interested in obtaining published studies (popular and scientific) about the wild mammals of South Dakota

    Feature weighting techniques for CBR in software effort estimation studies: A review and empirical evaluation

    Get PDF
    Context : Software effort estimation is one of the most important activities in the software development process. Unfortunately, estimates are often substantially wrong. Numerous estimation methods have been proposed including Case-based Reasoning (CBR). In order to improve CBR estimation accuracy, many researchers have proposed feature weighting techniques (FWT). Objective: Our purpose is to systematically review the empirical evidence to determine whether FWT leads to improved predictions. In addition we evaluate these techniques from the perspectives of (i) approach (ii) strengths and weaknesses (iii) performance and (iv) experimental evaluation approach including the data sets used. Method: We conducted a systematic literature review of published, refereed primary studies on FWT (2000-2014). Results: We identified 19 relevant primary studies. These reported a range of different techniques. 17 out of 19 make benchmark comparisons with standard CBR and 16 out of 17 studies report improved accuracy. Using a one-sample sign test this positive impact is significant (p = 0:0003). Conclusion: The actionable conclusion from this study is that our review of all relevant empirical evidence supports the use of FWTs and we recommend that researchers and practitioners give serious consideration to their adoption

    The potential for constructed wetlands to treat alkaline bauxite-residue leachate: phragmites australis growth

    Get PDF
    High alkalinity (pH > 12) of bauxite-residue leachates presents challenges for the long-term storage and managements of the residue. Recent evidence has highlighted the potential for constructed wetlands to effectively buffer the alkalinity, but there is limited evidence on the potential for wetland plants to establish and grow in soils inundated with residue leachate. A pot-based trial was conducted to investigate the potential for Phragmites australis to establish and grow in substrate treated with residue leachate over a pH range of 8.6–11.1. The trial ran for 3 months, after which plant growth and biomass were determined. Concentrations of soluble and exchangeable trace elements in the soil substrate and also in the aboveground and belowground biomass were determined. Residue leachate pH did not affect plant biomass or microbial biomass. With the exception of Na, there was no effect on exchangeable trace elements in the substrate; however, increases in soluble metals (As, Cd and Na) were observed with increasing leachate concentration. Furthermore, increases in Al, As and V were observed in belowground biomass and for Cd and Cr in aboveground biomass. Concentrations within the vegetation biomass were less than critical phytotoxic levels. Results demonstrate the ability for P. australis to grow in bauxite-residue leachate-inundated growth media without adverse effects

    Experimental phase diagram of moving vortices

    Full text link
    In the mixed state of type II superconductors, vortices penetrate the sample and form a correlated system due to the screening of supercurrents around them. Interestingly, we can study this correlated system as a function of density and driving force. The density, for instance, is controlled by the magnetic field, B, whereas a current density j acts as a driving force F=jxB on all vortices. The free motion of vortices is inhibited by the presence of an underlying potential, which tends to pin the vortices. Hence, to minimize the pinning strength we studied a superconducting glass in which the depinning current is 10 to 1000 times smaller than in previous studies, which enables us to map out the complete phase diagram in this new regime. The diagram is obtained as a function of B, driving current and temperature and led a remarkable set of new results, which includes a huge peak effect, an additional reentrant depinning phase and a driving force induced pinning phase.Comment: 4 page

    Analyzing confidentiality and privacy concerns: insights from Android issue logs

    Get PDF
    Context: Post-release user feedback plays an integral role in improving software quality and informing new features. Given its growing importance, feedback concerning security enhancements is particularly noteworthy. In considering the rapid uptake of Android we have examined the scale and severity of Android security threats as reported by its stakeholders. Objective: We systematically mine Android issue logs to derive insights into stakeholder perceptions and experiences in relation to certain Android security issues. Method: We employed contextual analysis techniques to study issues raised regarding confidentiality and privacy in the last three major Android releases, considering covariance of stakeholder comments, and the level of consistency in user preferences and priorities. Results: Confidentiality and privacy concerns varied in severity, and were most prevalent over Jelly Bean releases. Issues raised in regard to confidentiality related mostly to access, user credentials and permission management, while privacy concerns were mainly expressed about phone locking. Community users also expressed divergent preferences for new security features, ranging from more relaxed to very strict. Conclusions: Strategies that support continuous corrective measures for both old and new Android releases would likely maintain stakeholder confidence. An approach that provides users with basic default security settings, but with the power to configure additional security features if desired, would provide the best balance for Android's wide cohort of stakeholders

    Are you insulting me? Exposure to alcohol primes increases aggression following ambiguous provocation

    Get PDF
    Considerable research has shown that alcohol consumption can increase aggression and produce extremes in other social behaviors. Although most theories posit that such effects are caused by pharmacological impairment of cognitive processes, recent research indicates that exposure to alcohol-related constructs, in the absence of consumption, can produce similar effects. Here we tested the hypothesis that alcohol priming is most likely to affect aggression in the context of ambiguous provocation. Experiment 1 showed that exposure to alcohol primes increased aggressive retaliation but only when an initial provocation was ambiguous; unambiguous provocation elicited highly aggressive responses regardless of prime exposure. Experiment 2 showed that alcohol prime exposure effects are relatively short-lived and that perceptions of the provocateur’s hostility mediated effects of prime exposure on aggression. These findings suggest modification and extension of existing models of alcohol-induced aggressio
    • …
    corecore