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Escrito en español y en alemán.Presentación del número por parte de sus editores

Parámetros del orden de palabras y transferencia: factores internos de la adquisición del alemán como lengua extranjera

Tanto en el marco de la teoría de los principios y parámetros (Chomsky, 1981) como en el contexto de los estudios funcionalistas (Pienemann, 1989), el papel de la transferencia o influencia interlingüística en la adquisición de segundas lenguas se ha librado ya tiempos ha del sambenito conductista. Este artículo cotejará las distintas explicaciones del fenómeno del conocimiento previo en la interlengua de los aprendientes españoles del alemán, apoyándose en parte en datos obtenidos en un estudio propio.Acquisition studies realized in the frameworks of Principles and Parameters (Chomsky, 1981) and functionalist Natural Sequence Hypothesis (Pienemann, 1989), both have delivered transfer from its behaviourist aftertaste. This article compares the explanations of the syntactic effects of previous L1 knowledge in the Interlanguage of Spanish learners of German as L2, based on a study with first year University students

Constraining the near-surface response to lithospheric reorientation: Structural thermochronology along AlpArray geophysical transects

The shape of the present-day European Alps results from a complex tectonic and climatic history since the onset of convergence between the African and Eurasian plates. Low-temperature thermochronology data are a unique archive that can trace the cooling history of rocks back in time during exhumation from upper to middle crustal levels to Earth's surface. However, the precise mechanisms that led to cooling and exhumation are still debated. In this study, we investigated the potential for mantle processes, such as potential subducting slab break-off or slab reversal, to leave a fingerprint in the rock cooling record of the present-day surface along three key, north-south oriented geophysical transects: NFP-20E, TRANSALP and EASI. Along all transects, our zircon and apatite (U-Th)/He data reveal reset Neogene (and younger) cooling ages centred around core complexes such as the Lepontine Dome and the Tauern Window indicative of late exhumation during the Cenozoic Alpine orogeny. North and south of these complexes, the cooling ages become older, forming U-shaped age distributions around the reset centres. Thermal history reconstructions along TRANSALP confirm a conspicuous southward shift of cooling towards the Southern Alps approximately at the time of deep-seated exhumation of the Tauern Window driven by motion along the mid-crustal Tauern Ramp in the Mid-Miocene. Thermo-kinematic models along the transect confirm this southward shift of deformation and (i) reproduce the distribution of cooling ages and thermal history reconstructions, (ii) are consistent with the present-day structural geometry along the transect, (iii) and the observed surface heat flux. It is possible that rock cooling is primarily driven by rock displacement along active faults and less by climatic and/or mantle buoyancy forces, which are both not included in the applied modelling approach. Our comprehensive thermochronological analyses allow two interpretations concerning mantle processes: (i) Assuming a strong coupling between the subducting and overriding plate, hence, the applicability of doubly-vergent orogen kinematics, then the thermochronological data are most consistent with an ongoing reversal in continental subduction polarity. (ii) A high degree of decoupling would negate the possibility that mantle processes are archived in the thermochronological record

Deriving the exhumation history of the Alps with thermochronological data

Thermochronology is a unique tool to derive the exhumation history of rocks over millions of years. Exhumation in orogens is largely controlled by tectonic structures that formed during convergence. Therefore, thermochronological data can be used to reconstruct the geodynamic evolution of mountain ranges and, more precisely, the activity of large fault systems. The Alps are one of the best-studied mountain ranges, with several thousands of low-temperature thermochronological samples dated with a variety of methods (e.g. Herrman et al. 2013; Fox et al. 2015). In this study, we review the most recent thermochronological literature to summarise the exhumation history of the Alps and discuss their driving forces. The apatite (U-Th)/He system is sensitive to the most recent exhumation (closure temperature of ~60°C) and records in places the (over-)deepening and widening of valleys around the Alps (e.g., Valla et al. 2011; Glotzbach et al. 2011). The higher temperature systems, especially the ZFT system (closure temperature of ~240°C), reveal the location of deeper exhumation (>10 km) caused by large-scale fault activity (Fig. 1). While some parts of the Southern Alps and the northern part of the Western and Eastern Alps were not reset during the Alpine orogeny, most of the internal parts of the Alps reveal reset ZFT ages (Fig. 1). The timing of exhumation of these regions, however, varies significantly with distinct tectonic regions. The most recent ZFT ages are <15 Ma and located in the external crystalline massifs, the Lepontine Dome, and the Tauern Window. The latter two are exhumed by large-scale orogen-parallel extensional faulting and contemporaneous indentation. This event ceased in middle Miocene times when faulting and associated exhumation switched towards the Southern Alps (e.g. Eizenhöfer et al. 2021). Apatite fission-track ages (closure temperature of ~110°C) are the youngest (≤6 Ma) in the external crystalline massifs and record a long-lasting Miocene exhumation, whereas the early Miocene exhumation was caused by vertical tectonics related to rollback of the subducted European slab (e.g. Herwegh et al. 2017; 2019). Ongoing middle to late Miocene exhumation of the external crystalline massifs was instead related to in-sequence thrusting (Herwegh et al. 2019). The young thermochronological ages and related high post-Miocene exhumation in the western external crystalline massifs might be at least partly related to uplift caused by slab detachment (e.g. Fox et al. 2015). In the Eastern Alps, there is no evidence for comparable young (post-Miocene) exhumation ‘hotspots’, suggesting a rather stable geodynamic state and absence of large-scale changes in mantle processes

Resistance of αAI-1 transgenic chickpea (Cicer arietinum) and cowpea (Vigna unguiculata) dry grains to bruchid beetles (Coleoptera: Chrysomelidae)

Dry grain legume seeds possessing αAI-1, an α-amylase inhibitor from common bean (Phaseolus vulgaris), under the control of a cotyledon-specific promoter have been shown to be highly resistant to several important bruchid pest species. One transgenic chickpea and four cowpea lines expressing αAI-1, their respective controls, as well as nine conventional chickpea cultivars were assessed for their resistance to the bruchids Acanthoscelides obtectus (Say), Callosobruchus chinensis L. and Callosobruchus maculatus F. All transgenic lines were highly resistant to both Callosobruchus species. A. obtectus, known to be tolerant to αAI-1, was able to develop in all transgenic lines. While the cotyledons of all non-transgenic cultivars were highly susceptible to all bruchids, C. chinensis and C. maculatus larvae suffered from significantly increased mortality rates inside transgenic seeds. The main factor responsible for the partial resistance in the non-transgenic cultivars was deduced to reside in the seed coat. The αAI-1 present in seeds of transgenic chickpea and cowpea lines significantly increases their resistance to two important bruchid pest species (C. chinensis and C. maculatus) essentially to immunity. To control αAI-1 tolerant bruchid species such as A. obtectus and to avoid the development of resistance to αAI-1, varieties carrying this transgene should be protected with additional control measure

Constraining the geodynamic evolution of the Alps with sedimentary provenance and detrital thermochronometer data, II. Detrital thermochronology

This project was designed to disentangle sedimentary signals controlled by changes in the lithosphere, the upper crust, and climate change in the European Alps. The hypothesis was that if lithospheric reorganisation in the Alps (such as slab break-off or tearing) occurred, it would lead to spatio-temporal changes in buoyancy, influencing the location of rock uplift and erosion. Specifically, we wanted to test this hypothesis using a multi-proxy provenance approach (sedimentary provenance tools, detrital thermochronology) at key stratigraphic time slices (28, 25, 20, 17, 15, and 12 Ma) from the northern and southern foreland basins. Foreland basin deposits represent a rich archive of erosional processes controlled by tectonics, climate, and lithology. This presentation concerns part II of the study, the detrital thermochronology, which we use as "tracer thermochronology". Applications of tracer thermochronology exploit a known or assumed surface thermochronometric age map (based on either interpolated observed or modelled bedrock ages) to determine the provenance of detrital grains within fluvial or glacial catchments. The goal is to interpret the erosion pattern and processes within the sampled catchment. Before reconstructing and interpreting past erosion patterns and exhumation from detrital zircon fission-track (ZFT) age distributions and modelled bedrock ZFT ages back in time, we produce a frame of reference for today's situation. We do this by investigating signals from 26 modern river samples (21 previous [1,2] and nine new samples) and the present-day erosion pattern and mineral fertility in the Alps. We discuss observed and predicted (based on possible erosion scenarios) ZFT age distributions and potential pitfalls of the method (such as poor bedrock control in some areas of the Alps and challenges in combining previous and new data). Modern river results are consistent for adjacent, similar-size catchments and with expected erosion patterns. Most samples show a higher proportion of younger ZFT ages than would be predicted for uniform erosion and zircon fertility scenarios. Furthermore, we show preliminary results from stratigraphic sections from north and south of the Alps