Trihexyltetradecylphosphonium bis(Trifluoromethylsulfonyl) imide as inhibitor for 6063 aluminium alloy corrosion in physiological solution

369-374Aluminium alloys have found extensive use in several industrial, biological and dentistry applications, due to their high resistance towards corrosion in certain environments compared with carbon steels. Moreover, this choice is also related to the relatively low cost of the aluminium alloys. The use of aluminium alloys in the biological and dentistry related applications is of special importance. The addition of inhibitors presents an effective method for the reduction of the corrosion of the aluminium alloys in different environments. In this paper, the corrosion of 6063 aluminium alloy in physiological solution, with and without the addition of trihexyltetradecylphosphoniumbis(trifluoromethylsulfonyl) imide has been discussed. The influence of the inhibitor’s concentration on the corrosion rate of the 6063 aluminium alloy in physiological solution at 37°C, was studied using the weight loss and the potentiodynamic polarization techniques. The increase in the concentration of the trihexyltetradecylphosphoniumbis(trifluoromethylsulfonyl) imide added resulted in increased resistance of the 6063 aluminium alloy in the studied corrosion environment

Swedish Undergraduate Information Systems Curricula: A Comparative Study

The authors do a comprehensive comparison of the Swedish Information Systems undergraduate programs in order to on the one hand get a better understanding of how the Swedish curriculum compares to the Australian and US counter parts and on the other hand also get an understanding of where the IS field has changed over time. This change is debated to get a clearer view of what courses should be core in a post 2020 curriculum. The study points to some significant overlaps where Foundations of Information Systems, Data and Information Management, and Systems Analysis and Design are important for both Swedish, Australian, and US undergraduate IS programs. The study also shows differences in focus in the different countries curriculum, where the Swedish programs have a clear focus towards enterprise architecture and application development in comparison to both the Australian and US counterparts

Panel: A New Global Process for Revising and Maintaining the Undergraduate IS Model Curriculum

The panel will provide an overview and an analysis of the ongoing joint ACM/AIS IS undergraduate model curriculum revision project, which is proposing significant changes to both curriculum content and structure and the process that is used to develop and maintain IS model curricula. The panel members represent universities in Europe, Africa, and the Americas, and thus, the panel creates an excellent opportunity for an in-depth discussion regarding the regional differences in perspectives to curriculum development and the feasibility of a truly global IS model curriculum. The panel is structured to encourage active audience participation, and one of its purposes is to solicit feedback that will used to guide the curriculum development effort

Freire re-viewed

The work of Paulo Freire is associated with themes of oppression and liberation, and his critical pedagogy is visionary in its attempts to bring about social transformation. Freire has created a theory of education that embeds these issues within social relations that center around both ideological and material domination. In this review essay, Sue Jackson explores three books: Freire’s final work Pedagogy of Indignation; Cesar Augusto Rossatto’s Engaging Paulo Freire’s Pedagogy of Possibility, which attempts to engage Freire’s pedagogy of possibility; and C.A. Bowers and Frederique Apffel-Marglin’s edited collection Re-thinking Freire, which asks readers to reconsider Freire’s work in light of globalization and environmental crises. Jackson questions the extent to which Freire’s pedagogical approaches are useful to educators as well as to “the oppressed,” and whether challenges to re-think Freire can lead to new kinds of critical pedagogies

Exploring break-points and interaction effects among predictors of the international digital divide

Cataloged from PDF version of article.The deepening of the digital divide between countries has prompted international organizations and governments to work together toward reducing the problem over the next 15 years. However, such efforts will likely succeed only if they are based on a firm grasp of the divide's underlying causes. In this paper we report the results of a comprehensive analysis of the determinants of the international digital divide. Our results confirm many findings of past research, but also extend existing knowledge in important ways. By employing Multivariate Adaptive Regression Splines (MARS), we discover non-linearities and interaction effects among the predictors. We then articulate significant policy implications based upon these findings

Male reproductive adjustments to an introduced nest predator

Nest predation has a large impact on reproductive success in many taxa. Defending offspring from would-be predators can also be energetically and physiologically costly for parents. Thus, to maximize their reproductive payoffs, individuals should adjust their reproductive behaviors in relation to the presence of nest predators. However, effects of nest predator presence on parental behaviors across multiple reproductive contexts remain poorly understood, particularly in non-avian taxa. We ran a series of experiments to test how the presence of an egg predator, the invasive rockpool shrimp, Palaemon elegans, influences male reproductive decisions and egg survival in a species of fish with exclusive paternal care, the three-spined stickleback, Gasterosteus aculeatus. We found that, in the presence of shrimp, male sticklebacks were less likely to build a nest, invested less in territory defense against an intruder, and tended to fan eggs in their nest less and in shorter bouts, but did not alter their investment in courtship behavior. The predator's presence also did not affect egg survival rates, suggesting that males effectively defended their brood from the shrimp. These results show that reproducing individuals can be highly responsive to the presence of nest predators and adjust their behavioral decisions accordingly across a suite of reproductive contexts.Peer reviewe

Analysis of time-profiles with in-beam PET monitoring in charged particle therapy

Background: Treatment verification with PET imaging in charged particle therapy is conventionally done by comparing measurements of spatial distributions with Monte Carlo (MC) predictions. However, decay curves can provide additional independent information about the treatment and the irradiated tissue. Most studies performed so far focus on long time intervals. Here we investigate the reliability of MC predictions of space and time (decay rate) profiles shortly after irradiation, and we show how the decay rates can give an indication about the elements of which the phantom is made up. Methods and Materials: Various phantoms were irradiated in clinical and near-clinical conditions at the Cyclotron Centre of the Bronowice proton therapy centre. PET data were acquired with a planar 16x16 cm$^2$ PET system. MC simulations of particle interactions and photon propagation in the phantoms were performed using the FLUKA code. The analysis included a comparison between experimental data and MC simulations of space and time profiles, as well as a fitting procedure to obtain the various isotope contributions in the phantoms. Results and conclusions: There was a good agreement between data and MC predictions in 1-dimensional space and decay rate distributions. The fractions of $^{11}$C, $^{15}$O and $^{10}$C that were obtained by fitting the decay rates with multiple simple exponentials generally agreed well with the MC expectations. We found a small excess of $^{10}$C in data compared to what was predicted in MC, which was clear especially in the PE phantom.Comment: 9 pages, 5 figures, 1 table. Proceedings of the 20th International Workshop on Radiation Imaging Detectors (iWorid2018), 24-28 June 2018, Sundsvall, Swede

Understanding Eurasian convergence: Application of kohonen self-organizing maps

Kohonen self-organizing maps (SOMs) are employed to examine economic and social convergence of Eurasian countries based on a set of twenty-eight socio-economic measures. A core of European Union states is identified that provides a benchmark against which convergence of post-socialist transition economies may be judged. The Central European Visegrád countries and Baltics show the greatest economic convergence to Western Europe, while other states form clusters that lag behind. Initial conditions on the social dimension can either facilitate or constrain economic convergence, as discovered in Central Europe vis-à-vis the Central Asian Republics. Disquiet in the convergence literature is resolved by providing an analysis of the Eurasian states over time. Copyright © 2006 JMASM, Inc

Monitoring Proton Therapy Through In-Beam PET: An Experimental Phantom Study

In this paper, we investigate the use of a positron emission tomography (PET) system to monitor the proton therapy. The monitoring procedure is based on the comparison between the β+ activity generated in the irradiated volume during the treatment, with the β+ activity distribution obtained with Monte Carlo (MC) simulation. The dedicated PET system is a dual head detection system; each head is composed of nine scintillating LYSO crystal matrices read out independently with a custom modularized acquisition system. Our experimental data were acquired at the Cyclotron Centre Bronowice, Institute Nuclear Physics in Kraków, Poland, and were simulated with the FLUKA MC code. Homogeneous and heterogeneous plastic phantoms were irradiated with monoenergetic 130 MeV protons. The capabilities of our PET system to distinguish different irradiated materials were investigated, and the proton pencil-beams were used as probes. Our focus was to analyze the activity width and the total activity event number in several cases. Irradiations were performed using either single pencil-beams one at a time, or two pencil-beams during the same data taking. The comparison of 1-D activity profile for experimental data and MC simulation were always in good agreement showing that, the treatment quality assessment in proton therapy can be based on β+ activity measurements

Effects of driving conditions on secondary aerosol formation from a GDI vehicle using an oxidation flow reactor

A comprehensive study on the effects of photochemical aging on exhaust emissions from a vehicle equipped with a gasoline direct injection engine when operated over seven different driving cycles was assessed using an oxidation flow reactor. Both primary emissions and secondary aerosol production were measured over the Federal Test Procedure (FTP), LA92, New European Driving Cycle (NEDC), US06, and the Highway Fuel Economy Test (HWFET), as well as over two real-world cycles developed by the California Department of Transportation (Caltrans) mimicking typical highway driving conditions. We showed that the emissions of primary particles were largely depended on cold-start conditions and acceleration events. Secondary organic aerosol (SOA) formation also exhibited strong dependence on the cold-start cycles and correlated well with SOA precursor emissions (i.e., non-methane hydrocarbons, NMHC) during both cold-start and hot-start cycles (correlation coefficients 0.95–0.99), with overall emissions of ∼68–94 mg SOA per g NMHC. SOA formation significantly dropped during the hot-running phases of the cycles, with simultaneous increases in nitrate and ammonium formation as a result of the higher nitrogen oxide (NOx) and ammonia emissions. Our findings suggest that more SOA will be produced during congested, slow speed, and braking events in highways.acceptedVersionPeer reviewe