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Modelling the preferences of students for alternative assignment designs using the Discrete Choice Experiment methodology
This paper outlines how a discrete choice experiment (DCE) can be used to learn more about how students are willing to trade off various features of assignments such as the nature and timing of feedback and the method used to submit assignments. A DCE identifies plausible levels of the key attributes of a good or service and then presents the respondent with alternative bundles of these attributes and their levels and asks the respondent to choose between particular bundles. We report results from a DCE we conducted with undergraduate business students regarding their preferences for assignment systems. We find that the most important features of assignments are how relevant the assignments are for exam preparation and the nature of the feedback that students receive. We also find that students generally prefer online to paper assignments. We argue that the DCE approach has a lot of potential in education research. Accessed 4,497 times on https://pareonline.net from November 13, 2014 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right
Genetic-Algorithm-based Light Curve Optimization Applied to Observations of the W UMa star BH Cas
I have developed a procedure utilizing a Genetic-Algorithm-based optimization
scheme to fit the observed light curves of an eclipsing binary star with a
model produced by the Wilson-Devinney code. The principal advantages of this
approach are the global search capability and the objectivity of the final
result. Although this method can be more efficient than some other comparably
global search techniques, the computational requirements of the code are still
considerable. I have applied this fitting procedure to my observations of the W
UMa type eclipsing binary BH Cassiopeiae. An analysis of V-band CCD data
obtained in 1994/95 from Steward Observatory and U- and B-band photoelectric
data obtained in 1996 from McDonald Observatory provided three complete light
curves to constrain the fit. In addition, radial velocity curves obtained in
1997 from McDonald Observatory provided a direct measurement of the system mass
ratio to restrict the search. The results of the GA-based fit are in excellent
agreement with the final orbital solution obtained with the standard
differential corrections procedure in the Wilson-Devinney code.Comment: 9 pages, 2 figures, 2 tables, uses emulateapj.st
Implementation of an End-to-End Standards-based Patient Monitoring Solution
A proof-of-concept design of a patient monitoring solution for intensive care unit environments has been presented. It is end-to-end standard-based, using ISO/IEEE 11073 (X73) in the bedside environment and EN13606 to communicate the information to an electronic healthcare record (EHR) server. At the bedside end, the system is a plug-and-play sensor network communicating with a gateway that collects medical information and sends the data to a monitoring server. The monitoring server transforms this information into an EN13606 extract to be stored on the EHR server. The system has been implemented to comply with the last X73 and EN13606 available versions and tested in a laboratory environment to demonstrate the feasibility of an end-to-end standard-based solution
Constraining the properties of delta Scuti stars using spectroscopic eclipsing binary systems
Many stars exhibit stellar pulsations, favoring them for asteroseismic
analyses. Interpreting the oscillations requires some knowledge of the
oscillation mode geometry (spherical degree, radial and azimuthal orders). The
delta Scuti stars (1.5 - 2.5 M_sol) often show just one or few pulsation
frequencies. Although this may promise a successful seismological analysis, we
may not know enough about either the mode or the star to use the oscillation
frequency to improve the determination of the stellar model, or probe the
star's structure. For the observed frequencies to be used successfully as
seismic probes of these objects, we need to concentrate on stars for which we
can reduce the number of free parameters in the problem, such as binary systems
or open clusters. We investigate how much our understanding of a delta Scuti
star is improved when it is in a detached eclipsing binary system instead of
being a single field star. We use singular value decomposition to explore the
precision we expect in stellar parameters (mass, age and chemical composition)
for both cases. We examine how the parameter uncertainties propagate to the
luminosity - effective temperature diagram and determine when the effort of
obtaining a new measurement is justified. We show that for the single star, a
correct identification of the oscillation mode is necessary to produce strong
constraints on the stellar model properties, while for the binary system the
observations without the pulsation mode provide the same or better constraints
on the stellar parameters. In the latter case, ...Comment: emulateapj 16 pages, accepted Ap
Bond percolation on isoradial graphs: criticality and universality
In an investigation of percolation on isoradial graphs, we prove the
criticality of canonical bond percolation on isoradial embeddings of planar
graphs, thus extending celebrated earlier results for homogeneous and
inhomogeneous square, triangular, and other lattices. This is achieved via the
star-triangle transformation, by transporting the box-crossing property across
the family of isoradial graphs. As a consequence, we obtain the universality of
these models at the critical point, in the sense that the one-arm and
2j-alternating-arm critical exponents (and therefore also the connectivity and
volume exponents) are constant across the family of such percolation processes.
The isoradial graphs in question are those that satisfy certain weak conditions
on their embedding and on their track system. This class of graphs includes,
for example, isoradial embeddings of periodic graphs, and graphs derived from
rhombic Penrose tilings.Comment: In v2: extended title, and small changes in the tex
Cognitive Performance in Midlife Type 2 Diabetes: Results form the ENBIND Study
Aims: To establish the impact of uncomplicated type 2 diabetes on cognitive and neuropsychological performance in midlife. Methods: We performed a cross-sectional study of middle-aged adults with uncomplicated type 2 diabetes and a cohort of healthy control participants. General cognition was assessed using the Montreal Cognitive Assessment test and neuropsychological assessment was undertaken using a detailed neuropsychological assessment battery. Results: A total of 152 participants (102 with type 2 diabetes and 50 controls) were recruited (mean age 52 ± 8 years, 51% women). Participants with midlife type 2 diabetes were more than twice as likely to make an error on the Montreal Cognitive Assessment test [incidence rate ratio 2.44 (95% CI 1.54 to 3.87); P \u3c 0.001]. Further, type 2 diabetes was also associated with significantly lower memory composite score [ÎČ: â0.20 (95% CI â0.39 to â0.01); P = 0.04] and paired associates learning score [ÎČ: = â1.97 (95% CI â3.51, â0.43); P = 0.01] on the neuropsychological assessment battery following adjustment for age, sex, BMI, educational attainment and hypercholesterolaemia. Conclusions: Even in midlife, type 2 diabetes was associated with small but statistically significant cognitive decrements. These statistically significant decrements, whilst not clinically significant in terms of objective cognitive impairment, may have important implications in selecting out individuals most at risk of later cognitive decline for potential preventative interventions in midlife
Asteroseismology with the WIRE satellite. I. Combining Ground- and Space-based Photometry of the Delta Scuti Star Epsilon Cephei
We have analysed ground-based multi-colour Stromgren photometry and
single-filter photometry from the star tracker on the WIRE satellite of the
delta scuti star Epsilon Cephei. The ground-based data set consists of 16
nights of data collected over 164 days, while the satellite data are nearly
continuous coverage of the star during 14 days. The spectral window and noise
level of the satellite data are superior to the ground-based data and this data
set is used to locate the frequencies. However, we can use the ground-based
data to improve the accuracy of the frequencies due to the much longer time
baseline. We detect 26 oscillation frequencies in the WIRE data set, but only
some of these can be seen clearly in the ground-based data. We have used the
multi-colour ground-based photometry to determine amplitude and phase
differences in the Stromgren b-y colour and the y filter in an attempt to
identify the radial degree of the oscillation frequencies. We conclude that the
accuracies of the amplitudes and phases are not sufficient to constrain
theoretical models of Epsilon Cephei. We find no evidence for rotational
splitting or the large separation among the frequencies detected in the WIRE
data set. To be able to identify oscillation frequencies in delta scuti stars
with the method we have applied, it is crucial to obtain more complete coverage
from multi-site campaigns with a long time baseline and in multiple filters.
This is important when planning photometric and spectroscopic ground-based
support for future satellite missions like COROT and KEPLER.Comment: 13 pages, 12 figures, 4 tables. Fig. 4 reduced in quality. Accepted
by A&
Transitional palliative care interventions for older adults with advanced non-malignant diseases and frailty: a systematic review
Purpose: To identify transitional palliative care (TPC) interventions for older adults with non-malignant chronic diseases and complex conditions. Design/methodology/approach: A systematic review of the literature was conducted. CINAHL, Cochrane Library, Embase and Pubmed databases were searched for studies reporting TPC interventions for older adults, published between 2002 and 2019. The Crowe Critical Appraisal Tool was used for quality appraisal. Findings: A total of six studies were included. Outcomes related to TPC interventions were grouped into three categories: healthcare system-related outcomes (rehospitalisation, length of stay [LOS] and emergency department [ED] visits), patient-related outcomes and family/carer important outcomes. Overall, TPC interventions were associated with lower readmission rates and LOS, improved quality of life and better decision-making concerning hospice care among families. Outcomes for ED visits were unclear. Research limitations/implications: Positive outcomes related to healthcare services (including readmissions and LOS), patients (quality of life) and families (decision-making) were reported. However, the number of studies supporting the evidence were limited. Originality/value: Studies examining the effectiveness of existing care models to support transitions for those in need of palliative care are limited. This systematic literature review identified and appraised interventions aimed at improving transitions to palliative care in older adults with advanced non-malignant diseases or frailty
Effects of radial motion on interchange injections at Saturn
Charged particle injections are regularly observed in Saturn's inner magnetosphere by Cassini. They are attributed to an ongoing process of flux-tube interchange driven by the strong centrifugal force associated with Saturn's rapid rotation. Numerical simulations suggest that these interchange injections can be associated with inward flow channels, in which plasma confined to a narrow range of longitudes moves radially toward the planet, gaining energy, while ambient plasma in the adjacent regions moves more slowly outward. Most previous analyses of these events have neglected this radial motion and inferred properties of the events under the assumption that they appear instantaneously at the spacecraft's L-shell and thereafter drift azimuthally. This paper describes features of injections that can be related to their radial motion prior to observation. We use a combination of phase space density profiles and an updated version of a test-particle model to quantify properties of the injection. We are able to infer the longitudinal width of the injection, the radial travel time from its point of origin, and the starting L shell of the injection. We can also predict which energies can remain inside the channel during the radial transport. To highlight the effects of radial propagation at a finite speed, we focus on those interchange injections without extensive features of azimuthal dispersion. Injections that have traveled radially for one or more hours prior to observation would have been initiated at a different local time than that of the observation. Finally, we describe an injection where particles have drifted azimuthally into a flow channel prior to observation by Cassini. (C) 2015 Elsevier Inc. All rights reserved
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