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Distinguishing processing difficulties in inhibition, implicature, and negation
Despite their considerable communicative abilities, youngchildren often have difficulty interpreting complex linguisticstructures in context. Two examples of this phenomenon arenegation and pragmatic implicature, both of which pose some-times surprising difficulties for preschoolers. Both of thesestructures require children to resist a more salient alternativeinterpretation; since executive function abilities develop ex-tensively during childhood, perhaps failures are due to prob-lems in inhibition. To test this hypothesis, we designed tasksto measure inhibitory control, negation, and implicature com-prehension in children and adults. Using standard analyses aswell as drift diffusion models, we found different patterns ofprocessing on all three tasks, and no support for the hypothesisthat inhibitory control per se is playing a role in either adultsâor childrenâs negation or implicature processing. Instead, ouranalyses reveal qualitatively different developmental trajecto-ries, suggesting task-specific factors driving these changes
Analysis of nickel concentration profiles around the roots of the hyperaccumulator plant Berkheya coddii using MRI and numerical simulations
Investigations of soil-root interactions are hampered by the difficult experimental accessibility of the rhizosphere. Here we show the potential of Magnetic Resonance Imaging (MRI) as a non-destructive measurement technique in combination with numerical modelling to study the dynamics of the spatial distribution of dissolved nickel (Ni2+) around the roots of the nickel hyperaccumulator plant Berkheya coddii. Special rhizoboxes were used in which a root monolayer had been grown, separated from an adjacent inert glass bead packing by a nylon membrane. After applying a Ni2+ solution of 10mglâ1, the rhizobox was imaged repeatedly using MRI. The obtained temporal sequence of 2-dimensional Ni2+ maps in the vicinity of the roots showed that Ni2+ concentrations increased towards the root plane, revealing an accumulation pattern. Numerical modelling supported the Ni2+ distributions to result from advective water flow towards the root plane, driven by transpiration, and diffusion of Ni2+ tending to eliminate the concentration gradient. With the model, we could study how the accumulation pattern of Ni2+ in the root zone transforms into a depletion pattern depending on transpiration rate, solute uptake rate, and Ni2+ concentration in solutio
Aspirin Dosing for the Prevention and Treatment of Ischemic Stroke: An Indication-Specific Review of the Literature
OBJECTIVE: To evaluate the efficacy of aspirin for the treatment and prevention of ischemic stroke and identify the minimum dose proven to be effective for each indication.
DATA SOURCES: PubMed and MEDLINE searches (January 2009âJanuary 2010) were performed to identify primary literature, using search terms including aspirin, stroke prevention, acute ischemic stroke, acetylsalicylic acid, atrial fibrillation, myocardial infarction, and carotid endarterectomy. Additionally, reference citations from publications identified were reviewed.
STUDY SELECTION AND DATA EXTRACTION: Articles published in English were evaluated and relevant primary literature evaluating the efficacy of aspirin in the prevention of stroke was included in this review.
DATA SYNTHESIS: Antiplatelet therapy is the benchmark for the prevention of ischemic stroke. Aspirin has been proven to prevent ischemic stroke in a variety of settings. Despite the frequency at which aspirin continues to be prescribed in patients at risk of ischemic stroke, there remains confusion in clinical practice as to what minimum dose is required in various at-risk patients. A thorough review of the primary literature suggests that low-dose (50â81 mg daily) aspirin is insufficient for some indications. Acute ischemic stroke treatment requires 160â325 mg, while atrial fibrillation and carotid arterial disease require daily doses of 325 and 81â325 mg, respectively.
CONCLUSIONS: Available evidence suggests that aspirin dosing must be individualized according to indication. Recommendations provided by national guidelines at times recommend lower doses of aspirin than have been proven effective. Higher doses are indicated for stroke prevention in atrial fibrillation (325mg) and acute ischemic stroke patients (160â325 mg). Aspirin has not yet been proven effective for primary prevention of strokes in men, and a minimum dose for these patients cannot be determined from the available data
Siteâspecific weed managementâconstraints and opportunities for the weed research community: Insights from a workshop
The adoption of siteâspecific weed management (SSWM) technologies by farmers is not aligned with the scientific achievements in this field. While scientists have demonstrated significant success in realâtime weed identification, phenotyping and accurate weed mapping by using various sensors and platforms, the integration by farmers of SSWM and weed phenotyping tools into weed management protocols is limited. This gap was therefore a central topic of discussion at the most recent workshop of the SSWM Working Group arranged by the European Weed Research Society (EWRS). This insight paper aims to summarise the presentations and discussions of some of the workshop panels and to highlight different aspects of weed identification and spray application that were thought to hinder SSWM adoption. It also aims to share views and thoughts regarding steps that can be taken to facilitate future implementation of SSWM
Intracardiac 4D flow MRI in congenital heart disease : recommendations on behalf of the ISMRM flow & motion study group
Technical Efficacy: Stage 5 J. Magn. Reson. Imaging 2019.Cardiovascular Aspects of Radiolog
Radiomics-based aortic flow profile characterization with 4D phase-contrast MRI
4D PC MRI of the aorta has become a routinely available examination, and a multitude of single parameters have been suggested for the quantitative assessment of relevant flow features for clinical studies and diagnosis. However, clinically applicable assessment of complex flow patterns is still challenging. We present a concept for applying radiomics for the quantitative characterization of flow patterns in the aorta. To this end, we derive cross-sectional scalar parameter maps related to parameters suggested in literature such as throughflow, flow direction, vorticity, and normalized helicity. Derived radiomics features are selected with regard to their inter-scanner and inter-observer reproducibility, as well as their performance in the differentiation of sex-, age- and disease-related flow properties. The reproducible features were tested on user-selected examples with respect to their suitability for characterizing flow profile types. In future work, such signatures could be applied for quantitative flow assessment in clinical studies or disease phenotyping
Diurnal variations of reactive chlorine and nitrogen oxides observed by MIPAS-B inside the January 2010 Arctic vortex
The winter 2009/2010 was characterized by a strong Arctic vortex with
extremely cold mid-winter temperatures in the lower stratosphere associated
with an intense activation of reactive chlorine compounds (ClOx) from
reservoir species. Stratospheric limb emission spectra were recorded during
a flight of the balloon version of the Michelson Interferometer for Passive
Atmospheric Sounding (MIPAS-B) from Kiruna (Sweden) on 24 January 2010
inside the Arctic vortex. Several fast limb sequences of spectra (in time
steps of about 10 min) were measured from nighttime photochemical
equilibrium to local noon allowing the retrieval of chlorine- and
nitrogen-containing species which change rapidly their concentration around
the terminator between night and day. Mixing ratios of species like ClO,
NO2, and N2O5 show significant changes around sunrise, which
are temporally delayed due to polar stratospheric clouds reducing the direct
radiative flux from the sun. ClO variations were derived for the first time
from MIPAS-B spectra. Daytime ClO values of up to 1.6 ppbv are visible in a
broad chlorine activated layer below 26 km correlated with low values (below
0.1 ppbv) of the chlorine reservoir species ClONO2. Observations are
compared and discussed with calculations performed with the 3-dimensional
Chemistry Climate Model EMAC (ECHAM5/MESSy Atmospheric Chemistry). Mixing
ratios of the species ClO, NO2, and N2O5 are well reproduced
by the model during night and noon. However, the onset of ClO production and
NO2 loss around the terminator in the model is not consistent with the
measurements. The MIPAS-B observations along with Tropospheric
Ultraviolet-Visible (TUV) radiation model calculations suggest that polar
stratospheric clouds lead to a delayed start followed by a faster increase
of the photodissoziation of ClOOCl and NO2 near the morning terminator
since stratospheric clouds alter the direct and the diffuse flux of solar
radiation. These effects are not considered in the EMAC model simulations
which assume a cloudless atmosphere
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