Contextual diversity, not word frequency, determines word-naming and lexical decision times

Word frequency is an important predictor of word-naming and lexical decision times. It is, however, confounded with contextual diversity, the number of contexts in which a word has been seen. In a study using a normative, corpus-based measure of contextual diversity, word-frequency effects were eliminated when effects of contextual diversity were taken into account (but not vice versa) across three naming and three lexical decision data sets; the same pattern of results was obtained regardless of which of three corpora was used to derive the frequency and contextual-diversity values. The results are incompatible with existing models of visual word recognition, which attribute frequency effects directly to frequency, and are particularly problematic for accounts in which frequency effects reflect learning. We argue that the results reflect the importance of likely need in memory processes, and that the continuity between reading and memory suggests using principles from memory research to inform theories of reading

On The Impact of Passive Voice Requirements on Domain Modelling

Context: The requirements specification is a central arte- fact in the software engineering (SE) process, and its quality (might) influence downstream activities like implementation or testing. One quality defect that is often mentioned in standards is the use of passive voice. However, the con- sequences of this defect are still unclear. Goal: We need to understand whether the use of passive voice in requirements has an influence on other activities in SE. In this work we focus on domain modelling. Method: We designed an experiment, in which we ask students to draw a domain model from a given set of requirements written in active or passive voice. We compared the completeness of the resulting domain model by counting the number of missing actors, domain objects and their associations with respect to a specified solution. Results: While we could not see a difference in the number of missing actors and objects, participants which received passive sentences missed almost twice the associations. Conclusion: Our experiment indicates that, against common knowledge, actors and objects in a requirement can often be understood from the context. However, the study also shows that passive sentences complicate understanding how certain domain concepts are interconnected

Study of the Regeneration Cleaning of Used Mineral Oils – Ecotoxicological Properties and Biodegradation

The aim of the study was to establish and compare the model of the biodegradability and ecotoxicological properties of oil samples in aqueous environment.The unused new mineral oil Turbinol and used (after 1 year of usage) recovered oil Turbinol purified by the electrostatical method were the tested samples. For the determination of the ecotoxicological properties, the test organisms used were seeds of Sinapis alba L. and the small aquatic crustaceans Daphnia magna. Preliminary tests were positive and determined the acute toxicity with the values of IC50 and EC50. Biodegradability was determined by the manometric method, in tests which lasted 28 days. Tests of toxicity were positive, and the samples were found to be hard to biodegrade. Determination of the oil composition by gas chromatography with mass detection (GC – MS); found that the composition of the electrostatically cleaned oil is comparable to the new oil, which is confirmed by the results obtained with the response inhibition in selected tests. Regeneration extends the oil life, reducing the cost of disposal of waste oils, saving fossil raw materials, thus belonging to the environmentally friendly techniques. This work is licensed under a Creative Commons Attribution 4.0 International License

Priming Older Adults and People with Alzheimer’s Disease Analogical Problem Solving with True and False Memories

We investigated the extent to which activation of specific information in associative networks during a memory task could facilitate subsequent analogical problem solving in healthy older adults as well as those with early onset Alzheimer’s disease. We also examined whether these priming effects were stronger when the activation of the critical solution term during the memory task occurred when the item was actually presented (true memories) or when this item arose due to spreading activation to a related but nonpresented item (false memory). Older adult controls (OACs) and people with Alzheimer’s disease (AD) were asked to solve 9 verbal proportional analogies, 3 of which had been primed by Deese/Roediger-McDermott lists where the critical lure (and problem solution) was presented as a word in the list (true memory), 3 of which were primed by DRM lists whose critical lures were spontaneously activated during list presentation (false memory), and 3 of which were unprimed. As expected, OACs were better (both in terms of speed and accuracy) at solving problems than people with AD and both groups were better when false memories were primes than when true memories were primes or there were no primes. There were no reliable differences between unprimed and true prime problems. These findings demonstrate that (a) priming of problem solutions extends to verbal proportional analogies in OACs and people with AD, (b) false memories are more effective at priming problem solutions than true memories, and (c) there are clear positive consequences to the production of false memories

Magnetoresistance of a two-dimensional electron gas with spatially periodic lateral modulations: Exact consequences of Boltzmann's equation

On the basis of Boltzmann's equation, and including anisotropic scattering in the collision operator, we investigate the effect of one-dimensional superlattices on two-dimensional electron systems. In addition to superlattices defined by static electric and magnetic fields, we consider mobility superlattices describing a spatially modulated density of scattering centers. We prove that magnetic and electric superlattices in $x$-direction affect only the resistivity component $\rho_{xx}$ if the mobility is homogeneous, whereas a mobility lattice in $x$-direction in the absence of electric and magnetic modulations affects only $\rho_{yy}$. Solving Boltzmann's equation numerically, we calculate the positive magnetoresistance in weak magnetic fields and the Weiss oscillations in stronger fields within a unified approach.Comment: submitted to PR

Infrared magneto-optical properties of (III,Mn)V ferromagetic semiconductors

We present a theoretical study of the infrared magneto-optical properties of ferromagnetic (III,Mn)V semiconductors. Our analysis combines the kinetic exchange model for (III,Mn)V ferromagnetism with Kubo linear response theory and Born approximation estimates for the effect of disorder on the valence band quasiparticles. We predict a prominent feature in the ac-Hall conductivity at a frequency that varies over the range from 200 to 400 meV, depending on Mn and carrier densities, and is associated with transitions between heavy-hole and light-hole bands. In its zero frequency limit, our Hall conductivity reduces to the $\vec k$-space Berry's phase value predicted by a recent theory of the anomalous Hall effect that is able to account quantitatively for experiment. We compute theoretical estimates for magnetic circular dichroism, Faraday rotation, and Kerr effect parameters as a function of Mn concentration and free carrier density. The mid-infrared response feature is present in each of these magneto-optical effects.Comment: 11 pages, 5 figure

Spectropolarimetric observations of an arch filament system with the GREGOR solar telescope

Arch filament systems occur in active sunspot groups, where a fibril structure connects areas of opposite magnetic polarity, in contrast to active region filaments that follow the polarity inversion line. We used the GREGOR Infrared Spectrograph (GRIS) to obtain the full Stokes vector in the spectral lines Si I 1082.7 nm, He I 1083.0 nm, and Ca I 1083.9 nm. We focus on the near-infrared calcium line to investigate the photospheric magnetic field and velocities, and use the line core intensities and velocities of the helium line to study the chromospheric plasma. The individual fibrils of the arch filament system connect the sunspot with patches of magnetic polarity opposite to that of the spot. These patches do not necessarily coincide with pores, where the magnetic field is strongest. Instead, areas are preferred not far from the polarity inversion line. These areas exhibit photospheric downflows of moderate velocity, but significantly higher downflows of up to 30 km/s in the chromospheric helium line. Our findings can be explained with new emerging flux where the matter flows downward along the fieldlines of rising flux tubes, in agreement with earlier results.Comment: Proceedings 12th Potsdam Thinkshop to appear in Astronomische Nachrichte