The dynamism of strategic learning: Complexity theory in strategic L2 development

Learners of foreign languages (L2s) apply strategies to support learning processes and L2 development. They select strategies according to their individual needs and preferences and adjust their strategic actions to suit situational circumstances and contextual conditions. A holistic investigation of strategic L2 learning processes requires the integration of numerous interconnected, flexibly-interacting influences, which are at constant interplay with each other and whose development is difficult to predict. Validated as effective in other fields of applied linguistics, complex dynamic systems theory (CDST) can also provide an appropriate frame for researching strategic L2 learning. Based on state-of-the-art methodological guidance for complexity research, this article presents the re-analysis of empirical data from a previous study through a complexity lens. It further examines the suitability of CDST in strategy research, explores its practical value, and demonstrates that a complexity perspective can generate new, profound information about strategic learning

Past its expiry date? The SILL in modern mixed-methods strategy research

Has the Strategy Inventory for Language Learning (SILL) passed its expiry date? The SILL (Oxford, 1990) was designed as a self-evaluation tool to measure the frequency of language learning strategies used by foreign and second language (L2) learners. With simple mathematics, learners can analyze their strategy preferences overall and in six categories (i.e., memory, cognitive, compensation, metacognitive, affective, and social strategies). Diverging from its original purpose, the SILL became the most popular instrument in LLS research, which brought widespread acclaim but also criticism. This article explains what makes the SILL an extraordinary tool for learners, teachers, and researchers and how it can be adapted to suit specific contexts and the demands of a modern world. An example of how the SILL can be integrated into mixed-methods research demonstrates how the instrument can fulfil additional purposes to those originally intended. Despite its naturally quantitative orientation, the SILL contributed to the acquisition of rich qualitative information, which enabled a holistic view of five individual L2 learners. In addition to new insights about strategic L2 learning, the study attests that the SILL has not expired yet, but perhaps needs a modern touch, for instance, in the form of adaptation or combination with other research methods and the inclusion of strategies for learning language with technology

Heliospheric Evolution of Magnetic Clouds

Interplanetary evolution of eleven magnetic clouds (MCs) recorded by at least two radially aligned spacecraft is studied. The in situ magnetic field measurements are fitted to a cylindrically symmetric Gold-Hoyle force-free uniform-twist flux-rope configuration. The analysis reveals that in a statistical sense the expansion of studied MCs is compatible with self-similar behavior. However, individual events expose a large scatter of expansion rates, ranging from very weak to very strong expansion. Individually, only four events show an expansion rate compatible with the isotropic self-similar expansion. The results indicate that the expansion has to be much stronger when MCs are still close to the Sun than in the studied 0.47 - 4.8 AU distance range. The evolution of the magnetic field strength shows a large deviation from the behavior expected for the case of an isotropic self-similar expansion. In the statistical sense, as well as in most of the individual events, the inferred magnetic field decreases much slower than expected. Only three events show a behavior compatible with a self-similar expansion. There is also a discrepancy between the magnetic field decrease and the increase of the MC size, indicating that magnetic reconnection and geometrical deformations play a significant role in the MC evolution. About half of the events show a decay of the electric current as expected for the self-similar expansion. Statistically, the inferred axial magnetic flux is broadly consistent with it remaining constant. However, events characterized by large magnetic flux show a clear tendency of decreasing flux.Comment: 64 pages, 10 figure

Prediction of geomagnetic storm strength from inner heliospheric in situ observations

Prediction of the effects of coronal mass ejections (CMEs) on Earth strongly depends on knowledge of the interplanetary magnetic field southward component, B z . Predicting the strength and duration of B z inside a CME with sufficient accuracy is currently impossible, forming the so-called B z problem. Here, we provide a proof-of-concept of a new method for predicting the CME arrival time, speed, B z , and resulting disturbance storm time (Dst) index on Earth based only on magnetic field data, measured in situ in the inner heliosphere (<1 au). On 2012 June 12–16, three approximately Earthward-directed and interacting CMEs were observed by the Solar Terrestrial Relations Observatory imagers and Venus Express (VEX) in situ at 0.72 au, 6° away from the Sun–Earth line. The CME kinematics are calculated using the drag-based and WSA–Enlil models, constrained by the arrival time at VEX, resulting in the CME arrival time and speed on Earth. The CME magnetic field strength is scaled with a power law from VEX to Wind. Our investigation shows promising results for the Dst forecast (predicted: −96 and −114 nT (from 2 Dst models); observed: −71 nT), for the arrival speed (predicted: 531 ± 23 km s−1; observed: 488 ± 30 km s−1), and for the timing (6 ± 1 hr after the actual arrival time). The prediction lead time is 21 hr. The method may be applied to vector magnetic field data from a spacecraft at an artificial Lagrange point between the Sun and Earth or to data taken by any spacecraft temporarily crossing the Sun–Earth line

Drag-Based CME Modeling With Heliospheric Images Incorporating Frontal Deformation : ELEvoHI 2.0

The evolution and propagation of coronal mass ejections (CMEs) in interplanetary space is still not well understood. As a consequence, accurate arrival time and arrival speed forecasts are an unsolved problem in space weather research. In this study, we present the ELlipse Evolution model based on HI observations (ELEvoHI) and introduce a deformable front to this model. ELEvoHI relies on heliospheric imagers (HI) observations to obtain the kinematics of a CME. With the newly developed deformable front, the model is able to react to the ambient solar wind conditions during the entire propagation and along the whole front of the CME. To get an estimate of the ambient solar wind conditions, we make use of three different models: Heliospheric Upwind eXtrapolation model (HUX), Heliospheric Upwind eXtrapolation with time dependence model (HUXt), and EUropean Heliospheric FORecasting Information Asset (EUHFORIA). We test the deformable front on a CME first observed in STEREO-A/HI on February 3, 2010 14:49 UT. For this case study, the deformable front provides better estimates of the arrival time and arrival speed than the original version of ELEvoHI using an elliptical front. The new implementation enables us to study the parameters influencing the propagation of the CME not only for the apex, but for the entire front. The evolution of the CME front, especially at the flanks, is highly dependent on the ambient solar wind model used. An additional advantage of the new implementation is given by the possibility to provide estimates of the CME mass.Peer reviewe

Median Nerve Palsy following Elastic Stable Intramedullary Nailing of a Monteggia Fracture: An Unusual Case and Review of the Literature

Monteggia fractures are rare in children, and subtle radial head dislocations, with minor plastic deformation of the ulna, may be missed in up to a third of cases. Complications of Monteggia fractures-dislocations include persistent radial head dislocation, forearm deformity, elbow stiffness, and nerve palsies at the time of presentation. An unusual case of median nerve palsy following elastic stable intramedullary nailing of a type I Monteggia lesion in a 6-year-old girl is presented, and we highlight that, although most nerve palsies associated with a Monteggia fracture-dislocations are treated expectantly in children, early intervention here probably provided the best outcome