Pyrene degradation in the rhizosphere of tall fescue (Festuca arundinacea) and switchgrass (Panicum virgatum L.)

A growth chamber study was conducted to investigate the fate of pyrene in the rhizosphere of tall fescue (Festuca arundinacea) and switchgrass (Panicum virgatum L.). For this study, 14C-labeled pyrene was used, and distribution of 14C activity was assessed after plant establishment. After 190 days of incubation, 37.7 and 30.4% of 14C-pyrene was mineralized in the soil planted with tall fescue and switchgrass, respectively, while 4.3% mineralization was observed for the unplanted control. Only 7.6 and 8.7% of pyrene was recovered from the soil in the two planted treatments, while 31.5% of pyrene remained in the unplanted control. Significant amounts of 14C were observed for all treatments and controls in the humic/fulvic fraction of soil at the end of the experiment. This research indicates the potential for pyrene mineralization in planted systems, although the ultimate fate of degradation byproducts is uncertain.     

Rainbow: A framework for analysing computer-mediated pedagogical debates

In this paper we present a framework for analysing when and how students engage in a specific form of interactive knowledge elaboration in CSCL environments: broadening and deepening understanding of a space of debate. The framework is termed “Rainbow,” as it comprises seven principal analytical categories, to each of which a colour is assigned, thus enabling informal visualisation by the analyst of the extent to which students are engaging in interaction relating to potential achievement of its pedagogical goal. The categories distinguish between activities that are part of the prescribed assignment and activities that are not, and between task-focused and non-task-focused activities. Activities focused on managing the interaction itself are distinguished from argumentative interaction. Notably, an operational definition of what it means to broaden and deepen understanding in this case is also provided here. The functional Rainbow analysis is complemented by an analysis of topics and subtopics that enables identification of one form of conceptual deepening of the question. In comparison with existing analysis techniques, Rainbow synthesises much of what is known into a single framework, with a broad theoretical base. The usability and educational relevance of the framework has been validated experimentally across a variety of collaborative learning tasks and communication media. Possible and actual extensions to the framework are discussed, with respect to additional CSCL tools, domains and tasks. The research reported here was carried out within the SCALE project (Internet-based intelligent tool to Support Collaborative Argumentation-based Learning in secondary schools, project n° IST-1999–10664, March 2001 – February 2004), funded by the European Community under the ‘Information Societies’ Technology’ (IST) Programme. Information on the project can be found at: , or     

Computing with words and its relationships with fuzzistics

Words mean different things to different people, and so are uncertain. We, therefore, need a fuzzy set model for a word that has the potential to capture their uncertainties. In this paper I propose that an interval type-2 fuzzy set (IT2 FS) be used as a FS model of a word, because it is characterized by its footprint of uncertainty (FOU), and therefore has the potential to capture word uncertainties. Two approaches are presented for collecting data about a word from a group of subjects and then mapping that data into a FOU for that word. The person MF approach, in which each person provides their FOU for a word, is limited to fuzzy set experts because it requires the subject to be knowledgeable about fuzzy sets. The interval end-points approach, in which each person provides the end-points for an interval that they associate with a word on a prescribed scale is not limited to fuzzy set experts. Both approaches map data collected from subjects into a parsimonious parametric model of a FOU, and illustrate the combining of fuzzy sets and statistics—type-2 fuzzistics.     

Optimal choice of granularity in commonsense estimation: Why half‐orders of magnitude?

It has been observed that when people make crude estimates, they feel comfortable choosing between alternatives that differ by a half‐order of magnitude (e.g., were there 100, 300, or 1000 people in the crowd?) and less comfortable making a choice on a more detailed scale, with finer granules, or on a coarser scale (like 100 or 1000). In this article, we describe two models of choosing granularity in commonsense estimates, and we show that for both models, in the optimal granularity, the next estimate is three to four times larger than the previous one. Thus, these two optimization results explain the commonsense granularity. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 843–855, 2006.     

Homogenization of Periodically Varying Coefficients in Electromagnetic Materials

In this paper, we employ the periodic unfolding method for simulating the electromagnetic field in a composite material exhibiting heterogeneous microstructures which are described by spatially periodic parameters. We consider cell problems to calculate the effective parameters for a Debye dielectric medium in the case of a circular microstructure in two dimensions. We assume that the composite materials are quasi-static in nature, i.e., the wavelength of the electromagnetic field is much larger than the relevant dimensions of the microstructure.     

Transformation of the multimode terahertz quantum cascade laser beam into a Gaussian, using a hollow dielectric waveguide

We demonstrate that a short hollow dielectric tube can act as a dielectric waveguide and transform the multimode, highly diverging terahertz quantum cascade laser beam into the lowest order dielectric waveguide hybrid mode, EH(11), which then couples efficiently to the free-space Gaussian mode, TEM(00). This simple approach should enable terahertz quantum cascade lasers to be employed in applications where a spatially coherent beam is required.     

Promising CL‐20‐Based Energetic Material by Cocrystallization

A novel cocrystal (NEX‐1) of CL‐20 and MDNT is presented herein. The CL‐20: MDNT cocrystal, obtained in high yield by resonant acoustic mixing, shows new properties versus the discrete components. This is the first example of cocrystallization of CL‐20 where the new material is less sensitive to friction than CL‐20 itself, while demonstrating similar impact and ESD sensitivity. The CL‐20: MDNT cocrystal shows promise in the production of new energetic materials of interest by the cocrystallization of well‐characterized components.     

Effect of phenol on oxygen uptake rate of a laboratory population of Chironomus attenuatus (walk.)

A laboratory population of fourth-instar larval forms of Chironomus attenuatus Walker received a continuous life-long exposure of 0, 2.8, 8.2, 11.2, 16.3, and 22.4 ppm phenol. Measurements were taken of water temperature, pH, and dissolved oxygen concentration. Larvae exposed to the different phenol concentrations were analyzed for oven-dry weight and ash-free weight. The oxygen uptake was determined. The regression of oxygen uptake (Y), adjusted for phenol level, pH, and oxygen concentration, on ash-free weight (X) was log Y = 0.173–0.478 log X. The regression of adjusted oxygen uptake (Y) on phenol concentration (X) was Y = 1.632 + 0.299 log X. Calories lost through respiration (Y) were related to phenol level (X) by the equation, Y = (2.10 × 10^?3) + (3.86 × 10^?4) log X. The ash-free weight per individual (Y) decreased with increasing phenol concentration (X) as explained by the equation, Y = 0.753 ? 0.114 log X.     

Coupling Doppler radar‐derived wind maps with operational turbine data to document wind farm complex flows

The first known dual‐Doppler (DD) measurements collected within a utility‐scale wind farm are presented. Various complex flow features are discussed, including detailed analyses of turbine wakes, turbine‐to‐turbine interaction, high wind speed channels that exist between individual wakes and intermittent gust propagation. The data have been collected using innovative mobile Doppler radar technologies, which allows for a large observational footprint of ~17 km² in the presented analyses while maintaining spatial resolution of 0.49° in the azimuthal dimension by 15 m in the along‐beam range dimension. The presented DD syntheses provide three‐dimensional fields of the horizontal wind speed and direction with a revisit time of approximately 1 min. DD wind fields are validated with operational turbine data and are successfully used to accurately project composite power output for several turbines. The employed radar technologies, deployment schemes, scanning strategies and subsequent analysis methodologies offer the potential to contribute to the validation and improvement of current wake modeling efforts that influence wind farm design and layout practices, enhanced resource assessment campaigns, and provide real‐time wind maps to drive ‘smart’ wind farm operation. Copyright © 2014 John Wiley & Sons, Ltd.     

Characterization of drop-on-demand microdroplet printing

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) has been used extensively in the fabrication of polymer light-emitting diode displays by drop-on-demand inkjet printing technique. In order to make a good thin film with high uniformity, it is crucial to control the drying behavior of inkjet-printed PEDOT:PSS droplets. In this work, the morphology of printed drops of ～10 pL after drying was examined and explained in a qualitative manner, which would extend the comparison with previous work described in published literature. Results show that drying behavior is sensitive to substrate temperature due to the high surface-to-volume ratio of a microfluid. There exists an appropriate range of temperatures to obtain a good drop with sharp edge and flat surface. On the other hand, when the temperature exceeds a limit, a ring-like structure was observed. Results from this experiment would be considered as a reference to achieve uniform film after drying and has potential to be applied in the modeling of drop impact.