227 research outputs found
The effectiveness of therapies for dual language children with developmental language disorder: a systematic review of interventional studies
Purpose: This study aims to understand the effect of therapies on dual language children with developmental language disorder (DLD) on a range of bilingual language outcomes, compare with second-language-only therapy and determine whether there is any cross-linguistic transfer.
Methods: A systematic review of English articles in 10 electronic databases was conducted. Screening, reviewing and appraising were performed independently by two reviewers. Quality was appraised and findings synthesised in accordance with the research questions.
Results: Nine reports were identified. Five studies were found to be low in bias and therefore high in quality. Two were medium bias and two were high. Key findings were that instruction in the first language is required to support its continued acquisition and that bilingual instruction does not limit second language growth.
Conclusions: There is no identified evidence to suggest that second-language-only is better than bilingual therapy for dual language children with DLD for the development of the second language. There is evidence to suggest that bilingual therapy is equally effective for second language development, and also supports development of the first language. Further work is required to understand the efficacious doses of both languages in order to develop cost effective therapies and achieve optimal outcomes
New calibration procedures for airborne turbulence measurements and accuracy of the methane fluxes during the AirMeth campaigns
Low-level flights over tundra wetlands in Alaska and Canada have been conducted during the Airborne Measurements of Methane Emissions (AirMeth) campaigns to measure turbulent methane fluxes in the atmosphere. In this paper we describe the instrumentation and new calibration procedures for the essential pressure parameters required for turbulence sensing by aircraft that exploit suitable regular measurement flight legs without the need for dedicated calibration patterns. We estimate the accuracy of the mean wind and the turbulence measurements. We show that airborne measurements of turbulent fluxes of methane and carbon dioxide using cavity ring-down spectroscopy trace gas analysers together with established turbulence equipment achieve a relative accuracy similar to that of measurements of sensible heat flux if applied during low-level flights over natural area sources. The inertial subrange of the trace gas fluctuations cannot be resolved due to insufficient high-frequency precision of the analyser, but, since this scatter is uncorrelated with the vertical wind velocity, the covariance and thus the flux are reproduced correctly. In the covariance spectra the −7∕3 drop-off in the inertial subrange can be reproduced if sufficient data are available for averaging. For convective conditions and flight legs of several tens of kilometres we estimate the flux detection limit to be about 4mgm−2d−1 for w′CH4′, 1.4gm−2d−1 for w′CO2′ and 4.2Wm−2 for the sensible heat flux
Variability of the mixed layer height derived by ceilometer measurements in the Bavarian pre-Alps
The isolated neutron star RBS1774 revisited. Revised XMM-Newton X-ray parameters and an optical counterpart from deep LBT-observations
We report optical B-band observations with the Large Binocular Telescope LBT
of the isolated neutron star RBS1774. The stacked image with total exposure
2.5h reveals a candidate optical counterpart at mB = 26.96 +- 0.20 at position
RA(2000) = 21:43:03.4, DEC(2000)} = +06:54:17:5, within the joint Chandra and
XMM-Newton error circles. We analyse archival XMM-Newton observations and
derive revised spectral and positional parameters. The predicted optical flux
from the extrapolated X-ray spectrum is likely twice as high as reported
before. The measured optical flux exceeds the extrapolated X-ray spectral flux
by a factor ~40 (15 - 60 at 1sigma confidence). We interpret our detection and
the spectral energy distribution as further evidence of a temperature structure
over the neutron star's surface and present a pure thermal model reflecting
both the SED and the pulsed fraction of the light curve.Comment: 7 pages, 7 figures, submitted to A&
Fibrinolysis in a lipid environment: modulation through release of free fatty acids
Background: Thrombolysis is conventionally regarded as dissolution of the fibrin matrix of thrombi by plasmin, but the structure of clots in vivo includes additional constituents (proteins, phospholipids) that modulate their solubilization. Objective: We examined the presence of free fatty acids in thrombi and their effects on distinct stages of fibrinolysis (plasminogen activation, plasmin activity). Methods and Results: Using the fluorescent probe acrylodated intestinal fatty acid-binding protein, variable quantities (up to millimolar concentrations) of free fatty acids were demonstrated in surgically removed human thrombi. Oleic acid at relevant concentrations reversibly inhibits more than 90% of the amidolytic activity of plasmin on a synthetic substrate (Spectrozyme PL), but only partially inhibits its fibrinolytic activity measured using turbidimetry. Chromogenic assays detecting the generated plasmin activity show that plasminogen activation by tissue-type plasminogen activator (t-PA) is completely blocked by oleic acid in the fluid phase, but is accelerated on a fibrin matrix. A recombinant derivative of t-PA (reteplase) develops higher fibrin specificity in the presence of oleic acid, because both the inhibition of plasminogen activation in free solution and its enhancement on fibrin template are stronger than with wild-type t-PA. Conclusion: Through the stimulation of plasminogen activation on a fibrin template and the inhibition of plasminogen activators and plasmin in the fluid phase, free fatty acids confine the action of fibrinolytic proteases to the site of clotting, where they partially oppose the thrombolytic barrier function of phospholipids
A simple combinatorial treatment of constructions and threshold gaps of ramp schemes
We give easy proofs of some recent results concerning threshold gaps in ramp schemes. We then generalise a construction method for ramp schemes employing error-correcting codes so that it can be applied using nonlinear (as well as linear) codes. Finally, as an immediate consequence of these results, we provide a new explicit bound on the minimum length of a code having a specified distance and dual distance
Togo: Thorny transition and misguided aid at the roots of economic misery
The parliamentary elections of October 2007, the first free Togolese elections since decades, were meant to correct at least partially the rigged presidential elections of 2005. Western donors considered it as a litmus test of despotic African regimes’ propensity to change towards democratization and economic prosperity. They took Togo as model to test their approach of political conditionality of aid, which had been emphasised also as corner stone of the joint EU-Africa strategy. Empirical findings on the linkage between democratization and economic performance are challenged in this paper because of its basic data deficiencies. It is open to question, whether Togo’s expected economic consolidation and growth will be due to democratization of its institutions or to the improved external environment, notably the growing competition between global players for African natural resources
Shortened Tracer Uptake Time in GA-68-DOTATOC-PET of Meningiomas Does Not Impair Diagnostic Accuracy and PET Volume Definition
Ga-68-DOTATOC-PET/MRI can affect the planning target volume (PTV) definition of meningiomas before radiosurgery. A shorter tracer uptake time before image acquisition could allow the examination of more patients. The aim of this study was to investigate if shortening uptake time is possible without compromising diagnostic accuracy and PET volume. Fifteen patients (f = 12; mean age 52 years (34-80 years)) with meningiomas were prospectively examined with dynamic [68Ga]Ga-68-labeled [DOTA0-Phe1-Tyr3] octreotide (Ga-68-DOTATOC)-PET/MRI over 70 min before radiosurgery planning. Meningiomas were delineated manually in the PET dataset. PET volumes at each time point were compared to the reference standard 60 min post tracer injection (p.i.) using the Friedman test followed by a Wilcoxon signed-rank test and Bonferroni correction. In all patients, the earliest time point with 100% lesion detection compared to 60 min p.i. was identified. PET volumes did not change significantly from 15 min p.i. (p = 1.0) compared to 60 min p.i. The earliest time point with 100% lesion detection in all patients was 10 min p.i. In patients with meningiomas undergoing Ga-68-DOTATOC-PET, the tracer uptake time can safely be reduced to 15 min p.i. with comparable PET volume and 100% lesion detection compared to 60 min p.i
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