Search

Graph: Fig.1 Piperacillin (PIP) serum concentration achieved using a therapeutic drug monitoring-guided piperacillin/tazobactam dose titration decisional algorithm. We read with interest the study from Hagel et al I . i that found no beneficial effect of therapeutic drug monitoring (TDM)-based dose optimization of piperacillin/tazobactam (PIP/TAZ) on sepsis-related organ dysfunction in patients with sepsis [[1]]. [Extracted from the article]

The post-orogenic evolution of the European Variscan basement remains difficult to constrain due to the absence of post-orogenic sedimentary records. One of the current ways to access this history is to constrain the thermal evolution of these basement areas through indirect methods such as low-temperature thermochronology (LTT) thermal modelling. In this study, apatite fission-track (AFT) data have been acquired for the north-eastern part (Vendée and Limousin) of the French Massif Central Variscan basement. Similar thermal inversion procedure has been done, assuming that some samples were close to the surface during Triassic times. The results show a complex post-Variscan evolution of the western part of the Massif Central. Inversion of the AFT data indicates a high-temperature event during the Jurassic period. This thermal event can be interpreted as the deposition of a significant sedimentary cover which has been later eroded during the Late Jurassic and/or Early Cretaceous. Interpretation of the thermal models implies the presence of the sampled rocks close to the surface during Cretaceous and Eocene times. The estimated volume of this eroded sedimentary cover suggests a probable larger extension of the surrounding sedimentary basins (Paris Basin and Aquitaine Basin) across the Variscan basement area. [ABSTRACT FROM AUTHOR]

This article presents the results of a systematic review of the literature on dialogue-based CALL, resulting in a conceptual framework for research on the matter. Applications allowing a learner to have a conversation in a foreign language with a computer have been studied from various perspectives and under different names (dialogue systems, conversational agents, chatbots...). Considering the fragmentation of what we identify under the term dialogue-based CALL, we attempt to offer a structured overview of these efforts into a conceptual framework. Through a methodical search strategy, we collected a corpus of 343 publications. From this corpus, we formalized an operational definition of dialogue-based CALL, which allowed us to identify 96 relevant systems. Analyzing the type of dialogue they offer, on a continuum of constraints on form and meaning, we propose to classify those systems into four groups. We have called these branching, form-focused, goal-oriented and reactive systems, and we describe their corresponding interactional, instructional and technological traits. We summarize the main results from empirical studies on such systems, distinguishing observational, survey and experimental studies, and discuss the impact of dialogue-based CALL on motivation and L2 development, identifying positive evidence on both outcomes. Finally, we propose two main avenues for future research: relative effectiveness of dialogue-based CALL approaches, and dialogue systems as an environment for testing SLA hypotheses. [ABSTRACT FROM AUTHOR]

Abstract We present results from 2D and 3D thermo-mechanical studies of plume-lithosphere interactions in a rifted margin setting and compare inferences of these models with the Northern Atlantic volcanic rifted margin province. We first present a series of 2D models with three different initial locations of the plume: under the oceanic part of the rifted margin system; under the area affected by lithospheric thinning by passive rifting and under continental lithosphere which has not been affected by extension prior to plume emplacement. The style of final plume distribution appears to be controlled by its initial position with respect to different lithospheric segments and rheology of the mantle in the continent-ocean transitional zone rather than by other parameters such as external forcing and rheological structure of the mantle plume. The initial size of the mantle plume controls, to a large extent, the degree of plume head asymmetry. For a strong rheology of the overlaying transitional lithosphere, the effect of plume emplacement is mainly restricted to deep lithospheric levels. In contrast, a weak transitional mantle leads to plume-induced continental break-up when the plume head contributes to the formation of new oceanic lithosphere with asymmetrical propagation of hot plume material towards the continental segment. A common feature of most 2D models is that initially a hot plume weakens the overlying lithosphere, whereas at a later stage frozen mantle plume material is embedded into the lower part of the lithosphere, forming dense and high-velocity bodies. We extend our 2D numerical modelling study to three dimensions and investigate the first-order controls of continental break-up and plume emplacement. We demonstrate that the observed complex Iceland plume geometry with up to 400 km southern propagation can be reproduced numerically in 3D and explained by pre-imposed zones of lithospheric thinning along transform faults. Graphical abstract Image 2 Highlights • Inherited lithospheric structure and initial position of the mantle plume are key factors in plume-induced rifted margin evolution. • The degree of plume head asymmetry is largely controlled by the initial size of the mantle plume anomaly. • Iceland plume propagation can be explained by pre-existing zones of lithospheric thinning along major transform faults. [ABSTRACT FROM AUTHOR]

Abstract: Why some Archean cratons survived for billions of years while the rest of the lithosphere has been reworked, probably for several times, is both enigmatic and fundamental for plate tectonics. Craton longetivity is mainly explained by their buoyancy and analyzed by testing gravitational stability of hardly detectable cratonic mantle “keels” as a function of a hypothesized thermo-rheological structure. Destruction of some cratons suggests that buoyancy is not the only factor of their stability, and many previous studies show that their mechanical strength is equally important. The upper bounds on the integrated strength of cratons are provided by flexural studies demonstrating that T e values (equivalent elastic thickness) in cratons are highest in the world (110–150km). Yet, the lower bounds on the integrated strength of stable cratons are still a matter of debate, as well as the question on how this strength is partitioned between crust and mantle, and which set of rheological parameters is most pertinent. We show that primary observed cratonic features – flat topography and “frozen” heterogeneous crustal structure – represent the missing constraints for understanding of craton longevity. The cratonic crust is characterized by isostatically misbalanced density heterogeneities, suggesting that the lithosphere has to be strong enough to keep them frozen through time without developing major gravitational instabilities and topographic undulations. Hence, to constrain thermo-rheological properties of cratons one should investigate the stability of their topography and internal structure. Our free-surface thermo-mechanical numerical models demonstrate that craton stability cannot be warranted even by very high crustal strength, so that dry olivine mantle and cold thick lithosphere are indispensable conditions. We establish lower-bound limits on the thermo-rheological structure of cratons. In particular, we find that minimal T e needed for long-term stability of continents is approximately 90–110km of which at least 70km should be “contributed” by the lithosphere mantle. [Copyright &y& Elsevier]

Reading comprehension and fluency are crucial for successful academic learning and achievement. Yet, a rather large percentage of children still have enormous difficulties in understanding a written text at the end of primary school. In this context, the aim of our study was to investigate whether text simplification, a process of reducing text complexity while keeping its meaning unchanged, can improve reading fluency and comprehension for children learning to read. Furthermore, we were interested in finding out whether some readers would benefit more than others from text simplification as a function of their cognitive and language profile. To address these issues, we developed an iBook application for iPads, which allowed us to present normal and simplified versions of informative and narrative texts to 165 children in grade 2. Reading fluency was measured for each sentence, and text comprehension was measured for each text using multiple-choice questions. The results showed that both reading fluency and reading comprehension were significantly better for simplified than for normal texts. Results showed that poor readers and children with weaker cognitive skills (nonverbal intelligence, memory) benefitted to a greater extent from simplification than good readers and children with somewhat stronger cognitive skills. [ABSTRACT FROM AUTHOR]

The exhumation history of basement areas is poorly constrained because of large gaps in the sedimentary record. Indirect methods including low temperature thermochronology may be used to estimate exhumation, but these require an inverse modeling procedure to interpret the data. Solutions from such modelling are not always satisfactory as they may be too broad or may conflict with independent geological data. In this study, apatite fission-track (AFT) data have been compiled and newly acquired on the French Massif Central. Homogeneous thermal inversion has been realized assuming that some samples were close to the surface during Triassic times. The results show a complex post-Variscan evolution of the French Massif Central. Inversion of the AFT data characterizes high temperatures event during the Jurassic. Temperature range of this event is compatible with the deposition of a significant sedimentary cover which has been later eroded during Late Jurassic or Early Cretaceous, interpreted as a probable larger extension of the surrounding sedimentary basins (Paris Basin,AcquitaineBasin and Tethys). Interpretation of the thermal models suggest the presence of the samples close to the surface during Cretaceous and Eocene times. Despite the presence of small outliers of Late Cretaceous, no evidence is recorded excepted for the northern domain by the fission-track data for the deposition of a significant chalk cover as attested in different parts of western Europe.This study shows that the input of geological constraints is necessary to obtain a valuable and refined exhumation history and to reconstruct the presence of a former sedimentary cover presently completely eroded. The comparison between the different areas of the French Massif Central shows, in some case (e.g., Vendée, Morvan, Montagne Noire), a significant cooling during Paleocene related to the construction of the Pyrenean orogeny and illustrates that the Massif Central did not behave as a single unit during Mezo-Cenozoic times.This work is founded and carried out in the framework of the BRGM-TOTAL project Source-to-Sink. [ABSTRACT FROM AUTHOR]

Presents a detail from an illustration in "Fanni; ou, La nouvelle Paméla, histoire anglaise," by François-Thomas-Marie de Baculard d'Arnaud.

For normally sighted readers, word neighborhood size (i.e., the total number of words that can be formed from a single word by changing only one letter) has a facilitator effect on word recognition. When reading with central field loss (CFL) however, individual letters may not be correctly identified, leading to possible misidentifications and a reverse neighborhood size effect. Here we investigate this inhibitory effect of word neighborhood size on reading performance and whether it is modulated by word predictability and reading proficiency. Nineteen patients with binocular CFL from 32 to 89 years old (mean ± SD = 75 ± 15) read short sentences presented with the self-paced reading paradigm. Accuracy and reading time were measured for each target word read, along with its predictability, i.e., its probability of occurrence following the two preceding words in the sentence using a trigram analysis. Linear mixed effects models were then fit to estimate the individual contributions of word neighborhood size, predictability, frequency and length on accuracy and reading time, while taking patients' reading proficiency into account. For the less proficient readers, who have given up daily reading as a consequence of their visual impairment, we found that the effect of neighborhood size was reversed compared to normally sighted readers and of higher amplitude than the effect of frequency. Furthermore, this inhibitory effect is of greater amplitude (up to 50% decrease in reading speed) when a word is not easily predictable because its chances to occur after the two preceding words in a specific sentence are rather low. Severely impaired patients with CFL often quit reading on a daily basis because this task becomes simply too exhausting. Based on our results, we envision lexical text simplification as a new alternative to promote effective rehabilitation in these patients. By increasing reading accessibility for those who struggle the most, text simplification might be used as an efficient rehabilitation tool and daily reading assistive technology, fostering overall reading ability and fluency through increased practice. [ABSTRACT FROM AUTHOR]

People with central field loss (CFL) use peripheral vision to identify words. Eccentric vision provides ambiguous visual inputs to the processes leading to lexical access. Our purpose was to explore the hypothesis that this ambiguity leads to strong influences of inferential processes, our prediction being that increasing word frequency would decrease word reading time. Individuals with bilateral CFL induced by macular diseases read French sentences displayed with a self-paced reading method. Reading time of the last word of each sentence (target word) was recorded. Each target word (in sentence n) was matched with a synonym word (in sentence n+1) of the same length. When using absolute frequency value (Analysis 1), we found that reading time of target words decreased when word frequency increases, even when controlling for word length. The amplitude of this effect is larger than reported in previous investigations of reading with normal subjects. When comparing the effect of relative frequency (low vs. high) within each pair of synonyms (Analysis 2), results show the same pattern as the one observed in Analysis 1. Our results demonstrate clear-cut frequency effects on word reading time and suggest that inferential processes are stronger in CFL readers than in normally sighted observers. These results might also help design text simplification tools tailored for low-vision patients. [ABSTRACT FROM AUTHOR]

The location of the India-Arabia plate boundary prior to the formation of the Sheba ridge in the Gulf of Aden is a matter of debate. A seismic dataset crossing the Owen Fracture Zone, the Owen Basin, and the Oman Margin was acquired to track the past locations of the India-Arabia plate boundary. We highlight the composite age of the Owen Basin basement, made of Paleocene oceanic crust drilled on its eastern part, and composed of pre-Maastrichtian continental and oceanic crust overlaid by ophiolites emplaced in Early Paleocene on its western side. A major fossil transform fault system crossing the Owen Basin juxtaposed these two slivers of lithosphere of different ages, and controlled the uplift of marginal ridges along the Oman Margin. This transform system deactivated ∼40 Myrs ago, coeval with the onset of ultra-slow spreading at the Carlsberg Ridge. The transform boundary then jumped to the edge of the present-day Owen Ridge during the Late Eocene-Oligocene period, before seafloor spreading began at the Sheba Ridge. This migration of the plate boundary involved the transfer of a part of the Indian oceanic lithosphere formed at the Carlsberg Ridge to Arabia. This Late Eocene-Oligocene tectonic episode at the India-Arabia plate boundary is synchronous with a global plate reorganization event corresponding to geological events at the Zagros and Himalaya belts. The Owen Ridge uplifted later, in Late Miocene times, and is unrelated to any major migration of the India-Arabia boundary. [ABSTRACT FROM AUTHOR]

Subsidence and uplift patterns and thermal history of sedimentary basins are controlled by tectonics, mantle dynamics and surface processes, such as erosion, sediment transport and deposition and their links to climatic variations. We use combined thermo-mechanical and stratigraphic numerical modelling techniques to quantify the links between tectonic and surface processes. We aim to assess the thermal evolution and subsidence rates of asymmetric extensional basins during the syn- and post-rift times by simulating different erosion and sedimentation rates. We analyse the 3D sedimentary architecture and facies distribution of the depocenters. Model results are validated by observations in the Pannonian Basin of Central Europe. Extensional reactivation of inherited suture zones creates asymmetric basin systems controlled by large-scale detachments or low-angle normal faults, where crustal and lithospheric mantle thinning are often rheologically decoupled. Subsidence rates and basement heat flow in the depocenters show large variabilities during asymmetric extension and post-rift evolution controlled by their initial position from the suture zone and migration of deformation. Transient heat flow anomalies mirror crustal exhumation of footwalls, sediment blanketing and erosion effects in the basins. Enhanced erosion and sedimentation facilitate lower crustal deformation and elastic flexure of the weak, extended lithosphere leading to accentuated differential uplift and subsidence during the syn- and post-rift basin evolution. Tectonics, climate and autogenic processes control transgressive-regressive cycles at different timescales together with the overall sedimentary facies distribution. In our models assuming wet climate the high subsidence rate often outpaces moments of eustatic water-level fall preventing relative base-level fall and enhances the effects of autogenic processes, such as lobe switching processes. Unlabelled Image • Linking lithosphere-asthenosphere processes with sedimentation and erosion. • Heat flow evolution of asymmetric extensional basins is reconstructed. • Extensional pulses create stratigraphic sequences. • Stratal stacking patterns are simulated including eustatic and autogenic processes. [ABSTRACT FROM AUTHOR]

• The Late Cretaceous India-Africa Transform plate boundary is identified at Chain Ridge. • The Paleogene India-Africa transform plate boundary is identified at the Chain Fracture Zone and within the Owen Basin. • The Masirah ophiolites emplaced along a transform boundary. • The oceanic lithosphere subducting nowadays beneath Makran derives from the East Somali Basin instead of Neotethys. The Arabian Sea in the NW Indian Ocean is a place where two major transform boundaries are currently active: the Owen Fracture Zone between India and Arabia and the Owen Transform between India and Somalia. These transform systems result from the fragmentation of the India-Africa Transform boundary, which initiated about 90 Myrs ago, when the India-Seychelles block separated from Madagascar to move towards Eurasia. Therefore, the geological record of the Arabian Sea makes it possible to investigate the sensitivity of a transform system to several major geodynamic changes. Here we focus on the evolution of the India-Africa transform system during the ~47–90 Ma interval. We identify the Late Cretaceous (~90–65 Ma) transform plate boundary along Chain Ridge, in the North Somali Basin. From 65 to ~42–47 Ma, the India-Africa transform is identified at the Chain Fracture Zone, which crossed both the Owen Basin and the North East Oman margin. Finally, the transform system jumped to its present-day location in the vicinity of the Owen Ridge. These shifts of the India-Africa boundary with time provide a consistent paleogeographic framework for the emplacement of the Masirah Ophiolitic Belt, which constitutes a case of ophiolite emplaced along a transform boundary. The successive locations of the India-Africa boundary further highlight the origin of the Owen Basin lithosphere incoming into the Makran subduction zone. [ABSTRACT FROM AUTHOR]