316 research outputs found
The effect of the prompt on writing product and process: a mixed methods approach
A thesis submitted to the University of Bedfordshire in partial fulfilment of the requirements for the degree of Doctor of PhilosophyThe aim of this thesis is to investigate the effect of the writing prompt on test takers in terms of their test taking processes and the final written product in a second language writing assessment context. The study employs a mixed methods approach, with a quantitative and a qualitative strand. The quantitative study focuses on an analysis of the responses to six different writing prompts, with the responses being analyzed for significant differences in a range of key textual features, such as syntactic complexity, lexical sophistication, fluency and cohesion. The qualitative study incorporates stimulated recall interviews with test takers to learn about the aspects of the writing prompt that can have an effect on test taking processes, such as selecting a prompt, planning a response, and composing a response.
The results of the quantitative study indicate that characteristics of the writing prompt (domain, response mode, focus, number of rhetorical cues) have an effect on numerous textual features of the response; for example, fluency, syntactic complexity, lexical sophistication, and cohesion. The qualitative results indicate that similar characteristics of the writing prompt can have an effect on how test takers select a prompt, and that the test time constraint interacts with the prompt characteristics to affect how test takers plan and compose their responses. The topic and the number of rhetorical cues are the prompt characteristics that have the greatest effect on test taking processes.
The main conclusion drawn from the study findings are that several prompt characteristics should be controlled if prompts are to be considered equivalent. Without controlling certain prompt characteristics, both test taking processes and the written product will vary as a result of the prompt. The findings raise some serious questions regarding the inferences that may legitimately be drawn from writing scores. The findings provide clear guidance on prompt characteristics that should be controlled to help ensure that prompts present an equivalent challenge and opportunity to test takers to demonstrate their writing proficiency. This thesis makes an original contribution to the second language writing assessment literature in the detailed understanding of the relationships between specific prompt characteristics and textual features of the response
Geographic Health Disparities in Kentucky: Starting a Conversation About Local Solutions
A recently released map of Kentucky demonstrates how life expectancy varies across the stateâs 120 counties. The map vividly shows a decline in life expectancy as one travels east from the âGolden Triangleâ in central urban Kentucky to the mountains of Appalachia. The lowest life expectancies are largely in the far southeastern portion of the state, where residents of the Central Highlands have confronted adverse social determinants of health for generations. Indeed, companion maps released by the Center on Society and Health, which plot median household income, poverty, and educational attainment at the census tract level, show the stark socioeconomic disadvantage in this distressed Appalachian region. The maps are intended as âconversation startersâ to stimulate public discourse about the factors that shape health outcomes and to mobilize community concern and policy action to address health disparities in Appalachia. Meaningful change at the local level will be essential to transform the social and economic factors responsible for the regionâs health
The effects of either a mirror, internal or external focus instructions on single and multi-joint tasks
Training in front of mirrors is common, yet little is known about how the use of mirrors effects muscle force production. Accordingly, we investigated how performing in front of a mirror influences performance in single and multi-joint tasks, and compared the mirror condition to the established performance effects of internal focus (IF) and external focus (EF) instructions in a two part experiment. In the single-joint experiment 28 resistance-trained participants (14 males and 14 females) completed two elbow flexion maximal voluntary isometric contractions under four conditions: mirror, IF, EF and neutral instructions. During these trials, surface EMG activity of the biceps and triceps were recorded. In the multi-joint experiment the same participants performed counter-movement jumps on a force plate under the same four conditions. Single-joint experiment: EF led to greater normalized force production compared to all conditions (P †0.02, effect-size range [ES] = 0.46â1.31). No differences were observed between neutral and mirror conditions (P = 0.15, ES = 0.15), but both were greater than IF (PP â„ 0.1, ES = 0.10â0.21). Multi-joint experiment: Despite no statistical difference (P = 0.10), a moderate effect size was observed for jump height whereby EF was greater than IF (ES = 0.51). No differences were observed between neutral and mirror conditions (ES = 0.01), but both were greater than IF (ES = 0.20â22). The mirror condition led to superior performance compared to IF, inferior performance compared to EF, and was equal to a neutral condition in both tasks. These results provide novel and practical evidence concerning mirror training during resistance type training
Distinct subdivisions of the cingulum bundle revealed by diffusion MRI fibre tracking: Implications for neuropsychological investigations
The cingulum is a prominent white matter tract that supports prefrontal, parietal, and temporal lobe interactions. Despite being composed of both short and long association fibres, many MRI-based reconstructions ( tractography ) of the cingulum depict an essentially uniform tract that almost encircles the corpus callosum. The present study tested the validity of dividing this tract into subdivisions corresponding to the âparahippocampalâ, âretrosplenialâ, and âsubgenualâ portions of the cingulum. These three cingulum subdivisions occupied different medialâlateral locations, producing a topographic arrangement of cingulum fibres. Other comparisons based on these different reconstructions indicate that only a small proportion of the total white matter in the cingulum traverses the length of the tract. In addition, both the radial diffusivity and fractional anisotropy of the subgenual subdivision differed from that of the retrosplenial subdivision which, in turn, differed from that of the parahippocampal subdivision. The extent to which the radial diffusivity scores and the fractional anisotropy scores correlated between the various cingulum subdivisions proved variable, illustrating how one subdivision may not act as a proxy for other cingulum subdivisions. Attempts to relate the status of the cingulum, as measured by MRI-based fibre tracking, with cognitive or affective measures will, therefore, depend greatly on how and where the cingulum is reconstructed. The present study provides a new framework for subdividing the cingulum, based both on its known connectivity and MRI-based properties
A high-resolution pointing system for fast scanning platforms: The EBEX example
The E and B experiment (EBEX) is a balloon-borne telescope designed to
measure the polarization of the cosmic microwave background with 8' resolution
employing a gondola scanning with speeds of order degree per second. In January
2013, EBEX completed 11 days of observations in a flight over Antarctica
covering 6000 square degrees of the sky. The payload is equipped with
two redundant star cameras and two sets of three orthogonal gyroscopes to
reconstruct the telescope attitude. The EBEX science goals require the pointing
to be reconstructed to approximately 10" in the map domain, and in-flight
attitude control requires the real time pointing to be accurate to
0.5 . The high velocity scan strategy of EBEX coupled to its float
altitude only permits the star cameras to take images at scan turnarounds,
every 40 seconds, and thus requires the development of a pointing system
with low noise gyroscopes and carefully controlled systematic errors. Here we
report on the design of the pointing system and on a simulation pipeline
developed to understand and minimize the effects of systematic errors. The
performance of the system is evaluated using the 2012/2013 flight data, and we
show that we achieve a pointing error with RMS=25" on 40 seconds azimuth
throws, corresponding to an error of 4.6" in the map domain.Comment: 14 pages, Proceedings of the 2015 IEEE Aerospace Conferenc
An optimal ALMA image of the Hubble Ultra Deep Field in the era of JWST: obscured star formation and the cosmic far-infrared background
We combine archival ALMA data targeting the Hubble Ultra Deep Field (HUDF) to
produce the deepest currently attainable 1-mm maps of this key, extragalactic
survey field. Combining all existing data in Band 6, our deepest map covers
4.2arcmin^2, with a beamsize of 1.49"x1.07" at an effective frequency of 243GHz
(1.23mm). It reaches an rms of 4.6uJy/beam, with 1.5arcmin^2 below 9.0uJy/beam,
an improvement of >5% over the best previously published map and 50%
improvement in some regions. We also make a wider, but shallower map, covering
25.4arcmin^2. We detect 45 galaxies in the deep map down to 3.6sigma, including
10 more 1-mm sources than previously detected. 38 of these galaxies have a JWST
ID from the JADES NIRCam imaging and the new sources are typically faint and
red. A stacking analysis on the positions of ALMA-undetected JADES galaxies
yields detections for z<4 and stellar masses from 10^(8.4) to 10^(10.4)Msun,
extracting 10% of additional stacked signal from our map compared to previous
analyses. Detected sources and stacking contribute (10.0+/-0.5)Jy/deg^2 of the
cosmic infrared background (CIB) at 1.23mm. Although this is short of the
(uncertain) background level of about 20Jy/deg^2, after taking into account
intrinsic fluctuations in the CIB, our measurement is consistent with the
background if the HUDF is a mild (~2sigma) negative fluctuation. This suggests
that within the HUDF, JWST may have detected essentially all of the galaxies
that contribute to the CIB. Our stacking analysis predicts that the field
contains around 60 additional galaxies with 1.23mm flux densities averaging
around 15uJy, and over 300 galaxies at the few uJy level. However, the
contribution of these fainter more modestly-obscured objects to the background
is small, and converging, as anticipated from the now well-established strong
correlation between galaxy stellar mass and obscured star formation.Comment: Submitted to MNRA
Pharmacokinetics of once-daily extended-release tacrolimus tablets versus twice-daily capsules in de novo liver transplant
The pharmacokinetics of once-daily extended-release tacrolimus tablets (LCPT) in de novo liver transplantation have not been previously reported. In this phase II, randomized, open-label study, de novo liver transplant recipients were randomized to LCPT 0.07-0.13 mg/kg/day (taken once daily; n = 29) or twice-daily immediate-release tacrolimus capsules (IR-Tac) at 0.10-0.15 mg/kg/day (divided twice daily; n = 29). Subsequent doses of both drugs were adjusted to maintain tacrolimus trough concentrations of 5 to 20 ng/mL through day 90, and 5-15 ng/mL thereafter. Twenty-four-hour pharmacokinetic profiles were obtained on days 1, 7, and 14, with trough concentration and efficacy/safety monitoring through year 1. Similar proportions of patients in both groups achieved therapeutic trough concentrations on days 7 and 14 (day 7: LCPT = 78%, IR-Tac = 75%; day 14: LCPT = 86%, IR-Tac = 91%) as well as similar systemic and peak exposure. There was a robust correlation between drug concentration at time 0 and area under the concentration-time curve for both LCPT and IR-Tac (respectively, day 7: r = 0.86 and 0.79; day 14: r = 0.93 and 0.86; P \u3c .0001 for all). Dose adjustments during days 1 to 14 were frequent. Thirty-five patients completed the extended-use period. No significant differences in adverse events were seen between groups. Incidence of biopsy-proven acute rejection (LCPT = 6 and IR-Tac = 4) was similar on day 360. Between formulations, overall exposure was similar at 1 week after transplant with the characteristic delayed-release pharmacokinetic profile of LCPT demonstrated in this novel population. These data support further investigation of the safety and efficacy of LCPT in de novo liver transplantation
Identifying the Structure of the Intermediate, Li2/3CoPO4, Formed during Electrochemical Cycling of LiCoPO4.
In situ synchrotron diffraction measurements and subsequent Rietveld refinements are used to show that the high energy density cathode material LiCoPO4 (space group Pnma) undergoes two distinct two-phase reactions upon charge and discharge, both occurring via an intermediate Li2/3(Co2+)2/3(Co3+)1/3PO4 phase. Two resonances are observed for Li2/3CoPO4 with intensity ratios of 2:1 and 1:1 in the 31P and 7Li NMR spectra, respectively. An ordering of Co2+/Co3+ oxidation states is proposed within a (a Ă 3b Ă c) supercell, and Li+/vacancy ordering is investigated using experimental NMR data in combination with first-principles solid-state DFT calculations. In the lowest energy configuration, both the Co3+ ions and Li vacancies are found to order along the b-axis. Two other low energy Li+/vacancy ordering schemes are found only 5 meV per formula unit higher in energy. All three configurations lie below the LiCoPO4-CoPO4 convex hull and they may be readily interconverted by Li+ hops along the b-direction.This is the final version. It was first published by ACS Publications at http://pubs.acs.org/doi/abs/10.1021/cm502680
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