The information design of ecological cycle network diagrams in science textbooks

Network diagrams of ecological cycles, eg, carbon and nitrogen cycles, are a common feature in science textbooks for 14-18 years age groups. From an information design perspective these diagrams raise a particularly interesting challenge; that of categorising up to six types of biological information using two graphic syntactic roles – nodes and connecting arrows – whilst ensuring an efective and unambiguous message. This practice-led thesis reviews the precision of information categorisation in 209 network diagrams collected from UK and Danish science textbooks (1935-2009). Visual content analysis and graphic syntax theory (Engelhardt, 2002) is applied to review the existing information categorisation in relation to four types of graphic inefectiveness: 1) implicit nodes, 2) imprecise relative spatial positioning of graphic objects, 3) polysemy, and 4) inconsistent visual attributes or verbal syntax. This review finds 29 types of ineffective graphic tactics, which may result in ambiguous messages due to illogical linking sequences, implicit circulating elements, and confusion about chemical transfer and transformations. Based on these analysis indings, the design process in educational publishing is investigated. This identifies the rationale informing the transformation of information into network diagrams, based on semi- structured interviews with 19 editors, authors, designers, and illustrators in six publishing houses (3 in UK , 3 in Denmark). The rationale is mapped using phenomenographic analysis method and existing theories on the design process, namely brief development and translation stages (Crilly, 2005), choice points and the problem setting process (Schön, 2006), problem- solution co-evolution (Dorst and Cross, 2001), and design constraints (Lawson, 2006). The curriculum purpose of the ecological cycle network diagram is found to tightly constrain the identiied rationale and the graphic decision-making based mainly on tacit knowledge. In a final discussion the research indings are integrated by identifying models of design activities (Dumas and Mintzberg, 1993) present in investigated professional practice. This reveals how design decisions may inluence the occurrence of inefective graphic tactics. Recommendations for alternative information transformation strategies are then presented, centred on integrating graphic syntax knowledge into the current processes. These recommendations are anchored in suggestions by the interviewed participants

Computing Similarity between a Pair of Trajectories

With recent advances in sensing and tracking technology, trajectory data is becoming increasingly pervasive and analysis of trajectory data is becoming exceedingly important. A fundamental problem in analyzing trajectory data is that of identifying common patterns between pairs or among groups of trajectories. In this paper, we consider the problem of identifying similar portions between a pair of trajectories, each observed as a sequence of points sampled from it. We present new measures of trajectory similarity --- both local and global --- between a pair of trajectories to distinguish between similar and dissimilar portions. Our model is robust under noise and outliers, it does not make any assumptions on the sampling rates on either trajectory, and it works even if they are partially observed. Additionally, the model also yields a scalar similarity score which can be used to rank multiple pairs of trajectories according to similarity, e.g. in clustering applications. We also present efficient algorithms for computing the similarity under our measures; the worst-case running time is quadratic in the number of sample points. Finally, we present an extensive experimental study evaluating the effectiveness of our approach on real datasets, comparing with it with earlier approaches, and illustrating many issues that arise in trajectory data. Our experiments show that our approach is highly accurate in distinguishing similar and dissimilar portions as compared to earlier methods even with sparse sampling

Maintaining Contour Trees of Dynamic Terrains

We consider maintaining the contour tree $\mathbb{T}$ of a piecewise-linear triangulation $\mathbb{M}$ that is the graph of a time varying height function $h: \mathbb{R}^2 \rightarrow \mathbb{R}$. We carefully describe the combinatorial change in $\mathbb{T}$ that happen as $h$ varies over time and how these changes relate to topological changes in $\mathbb{M}$. We present a kinetic data structure that maintains the contour tree of $h$ over time. Our data structure maintains certificates that fail only when $h(v)=h(u)$ for two adjacent vertices $v$ and $u$ in $\mathbb{M}$, or when two saddle vertices lie on the same contour of $\mathbb{M}$. A certificate failure is handled in $O(\log(n))$ time. We also show how our data structure can be extended to handle a set of general update operations on $\mathbb{M}$ and how it can be applied to maintain topological persistence pairs of time varying functions

Preparation of high crystalline nanoparticles of rare-earth based complex pervoskites and comparison of their structural and magnetic properties with bulk counterparts

A simple route to prepare Gd$_{0.7}$Sr$_{0.3}$MnO$_3$ nanoparticles by ultrasonication of their bulk powder materials is presented in this article. For comparison, Gd$_{0.7}$Sr$_{0.3}$MnO$_3$ nanoparticles are also prepared by ball milling. The prepared samples are characterized by X-ray diffraction (XRD),field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscope (XPS), and Superconducting Quantum Interference Device (SQUID) magnetometer. XRD Rietveld analysis is carried out extensively for the determination of crystallographic parameters and the amount of crystalline and amorphous phases. FESEM images demonstrate the formation of nanoparticles with average particle size in the range of 50-100 nm for both ultrasonication and 4 hours (h) of ball milling. The bulk materials and nanoparticles synthesized by both ultrasonication and 4 h ball milling exhibit a paramagnetic to spin-glass transition. However, nanoparticles synthesized by 8 h and 12 h ball milling do not reveal any phase transition, rather show an upturn of magnetization at low temperature. The degradation of the magnetic properties in ball milled nanoparticles may be associated with amorphization of the nanoparticles due to ball milling particularly for milling time exceeding 8 h. This investigation demonstrates the potential of ultrasonication as a simple route to prepare high crystalline rare-earth based manganite nanoparticles with improved control compared to the traditional ball milling technique.Comment: 9 pages, 6 figure

The Danish Veterinary and Food Administration’s Fight against Fake Nutrition News on Digital Media

This article examines fake nutrition news on digital media and the steps the Danish Veterinary and Food Administration (DVFA) are taking to counteract this development. Through a critical discourse analysis of four cases, we aim to shed light on the DVFA’s tactics to counteract the fake nutrition news phenomenon and discuss how the development of digital media has affected the spreading of fake news and alternate methods to combat fake news. The article concludes that the DVFA use discourses of responsibility and credibility to combat fake news and promote their strategy by establishing themselves as a credible source who consumers should trust.Denne artikel undersøger fake nutrition news på digitale medier, og hvordan Fødevarestyrelsen modarbejder denne udvikling. Gennem en kritisk diskursanalyse af fire cases ønsker vi at belyse Fødevarestyrelsens taktik til at modvirke fake news fænomenet og diskutere, hvordan udviklingen af digitale medier har påvirket spredningen af fake news samt alternative metoder til at bekæmpe fake news. Artiklen konkluderer, at Fødevarestyrelsen bruger ansvars- og troværdighedsdiskurser til at bekæmpe fake news og promovere deres strategi ved at fastsætte dem selv som en troværdig kilde, som forbrugere bør stole på

Novel Micro-fabricated Chip With Micro-channels for In-situ Observation of Liquid Samples and Processes in TEM

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.</jats:p

Engineering the Surface/Interface Structures of Titanium Dioxide Micro and Nano Architectures towards Environmental and Electrochemical Applications

Titanium dioxide (TiO2) materials have been intensively studied in the past years because of many varied applications. This mini review article focuses on TiO2 micro and nano architectures with the prevalent crystal structures (anatase, rutile, brookite, and TiO2(B)), and summarizes the major advances in the surface and interface engineering and applications in environmental and electrochemical applications. We analyze the advantages of surface/interface engineered TiO2 micro and nano structures, and present the principles and growth mechanisms of TiO2 nanostructures via different strategies, with an emphasis on rational control of the surface and interface structures. We further discuss the applications of TiO2 micro and nano architectures in photocatalysis, lithium/sodium ion batteries, and Li–S batteries. Throughout the discussion, the relationship between the device performance and the surface/interface structures of TiO2 micro and nano structures will be highlighted. Then, we discuss the phase transitions of TiO2 nanostructures and possible strategies of improving the phase stability. The review concludes with a perspective on the current challenges and future research directions