153 research outputs found
Alternative Assessments and Student Perceptions in the Foreign Language Classroom
The paradigm shift in education with the implementation of the Common Core State Standards has created the opportunity for foreign language educators to evaluate appropriate and beneficial assessments for their students. This study investigated how first-year students in a Midwestern high school perceived three different alternative assessments in the foreign language classroom: Dynamic Assessment, Task-based Assessment, and Formative Assessment using self- and peer-evaluation. The researcher correlated the perceptions to the students’ assessment scores. Additionally, the researcher compared final exam scores of the control group to those of the experimental group. The results indicated that the experimental group students favorably perceived the alternative assessments types, chose Formative Assessment as their most preferred and Task-based Assessment as the least desired, and scored as well as the control group students on the final exam
On the value of foreign PhDs in the developing world: Training versus selection effects
This paper compares the career effects of overseas and domestic PhD training for scientists working in an emerging economy, South Africa. Variations in scientific achievements of South African academics may arise because those who attend \better" PhD programmes receive better training, but it may also be because good students select into good universities. We examine selection and training effects for four tiers of South African and two tiers of foreign universities. Those who received PhDs from universities in industrialized countries tend to be more productive than those whose PhDs were locally granted, but universities from industrialized countries do not necessarily provide better training than local universities. Pure selection effects contribute to career outcomes nearly as much as training effects. When looking at training in isolation, PhDs from top South African universities produce a similar quantity and quality research output to those from leading universities in the developed world
The role of local colleagues in establishing international scientific collaboration : social capital in emerging science systems
International collaborations are important for developing science systems. Using a dataset of South African university scientists, we ask whether social capital relevant to international collaboration held by one scientist spills over to local colleagues. Distinguishing between different ways of acquiring foreign ties, we find that 20% of our cases resemble the most-studied form of international collaborations, via the unique ties of an individual with specific characteristics, e.g., foreign research training. In all other cases, both personal and local peers’ international social capital is relevant for foreign tie formation. Underlining the systemic functioning of science, international social capital is activated through scientific collaboration among local scientists. The mediating effect of local scientific collaboration is present across all scientific fields and holds for scientists trained locally or abroad. Our findings thus imply that local collaboration is a relevant mechanism to strengthen international collaboration and the formation of international social capital.https://academic.oup.com/icchj2023Gordon Institute of Business Science (GIBS
Including excluded groups: The slow racial transformation of the South African university system
This paper looks at the inclusion of excluded groups, notably the racial transformation of the South African university system. Both demand-side factors | are qualified black people hired as faculty? | and supply-side factors | are there enough qualified black people who can be hired as faculty? | need to be aligned. Prior evidence suggests that demand and supply both have both a psychological and a structural dimension. Affirmative action-type regulations address the structural dimension of demand, but homophily (a "love for the own") can nonetheless limit the hiring of faculty in white-dominated hiring committees. On the supply side, the weak education system limits the structural supply of quality black potential academics. But the limited hiring of black academics and resulting limited role models mean that few black people even consider an academic career. This paper presents a model of hiring (either randomly or on a homophilic basis), calibrated with data from the South African university system from the end of Apartheid. Our evidence suggests that even a relatively small reduction of
homophily increases the rate at which the excluded group enters the workforce, and also that the effects of homophily and feedback from previous hires are of a similar magnitude. Nonetheless, the conclusions from the model suggest that the relatively long duration of a research career and slow growth of the national university system will result in a slow process of racial transformation
Transforming Acquisitions and Collection Services: Perspectives on Collaboration Within and Across Libraries
This book explores ways in which libraries can reach new levels of service, quality, and efficiency while minimizing cost by collaborating in acquisitions. In consortial acquisitions, a number of libraries work together, usually in an existing library consortia, to leverage size to support acquisitions in each individual library. In cross-functional acquisitions, acquisitions collaborates to support other library functions. For the library acquisitions manager, technical services manager, or the library director, awareness of different options for effective consortial and cross-functional acquisitions allows for the optimization of staff and resources to reach goals. This work presents those options in the form of case studies, as well as useful analysis of the benefits and challenges of each.
By supporting each other’s acquisitions services in a consortium, libraries leverage size to get better prices, and share systems and expertise to maximize resources while minimizing costs. Within libraries, the library acquisitions function can be combined with other library functions in a unit with more than one purpose, or acquisitions can develop a close working relationship with another unit to support their work. This book surveys practice at different libraries and at different library consortia, and presents a detailed description and analysis of a variety of practices for how acquisitions units support each other within a consortium, and how they work with other library units, specifically collection management, cataloging, interlibrary loan, and the digital repository, in the form of case studies. A final sections of the book covers fundamentals of collaboration.https://docs.lib.purdue.edu/purduepress_previews/1034/thumbnail.jp
On the Spin of the Black Hole in IC 10 X-1
The compact X-ray source in the eclipsing X-ray binary IC 10 X–1 has reigned for years as ostensibly the most massive stellar-mass black hole, with a mass estimated to be about twice that of its closest rival. However, striking results presented recently by Laycock et al. reveal that the mass estimate, based on emission-line velocities, is unreliable and that the mass of the X-ray source is essentially unconstrained. Using Chandra and NuSTAR data, we rule against a neutron-star model and conclude that IC 10 X–1 contains a black hole. The eclipse duration of IC 10 X–1 is shorter and its depth shallower at higher energies, an effect consistent with the X-ray emission being obscured during eclipse by a Compton-thick core of a dense wind. The spectrum is strongly disk-dominated, which allows us to constrain the spin of the black hole via X-ray continuum fitting. Three other wind-fed black hole systems are known; the masses and spins of their black holes are high: M ~ 10 - 15M_☉ and ɑ_* > 0.8. If the mass of IC 10 X-1's black hole is comparable, then its spin is likewise high
Automated bolus advisor control and usability study (ABACUS): does use of an insulin bolus advisor improve glycaemic control in patients failing multiple daily insulin injection (MDI) therapy? [NCT01460446]
BACKGROUND: People with T1DM and insulin-treated T2DM often do not follow and/or adjust their insulin regimens as needed. Key contributors to treatment non-adherence are fear of hypoglycaemia, difficulty and lack of self-efficacy associated with insulin dose determination. Because manual calculation of insulin boluses is both complex and time consuming, people may rely on empirical estimates, which can result in persistent hypoglycaemia and/or hyperglycaemia. Use of automated bolus advisors (BA) has been shown to help insulin pump users to more accurately meet prandial insulin dosage requirements, improve postprandial glycaemic excursions, and achieve optimal glycaemic control with an increased time within optimal range. Use of a BA containing an early algorithm based on sliding scales for insulin dosing has also been shown to improve HbA1c levels in people treated with multiple daily insulin injections (MDI). We designed a study to determine if use of an automated BA can improve clinical and psychosocial outcomes in people treated with MDI. METHODS/DESIGN: The Automated Bolus Advisor Control and Usability Study (ABACUS) is a 6-month, prospective, randomised, multi-centre, multi-national trial to determine if automated BA use improves glycaemic control as measured by a change in HbA1c in people using MDI with elevated HbA1c levels (#62;7.5%). A total of 226 T1DM and T2DM participants will be recruited. Anticipated attrition of 20% will yield a sample size of 90 participants, which will provide #62;80% power to detect a mean difference of 0.5%, with SD of 0.9%, using a one-sided 5% t-test, with 5% significance level. Other measures of glycaemic control, self-care behaviours and psychosocial issues will also be assessed. DISCUSSION: It is critical that healthcare providers utilise available technologies that both facilitate effective glucose management and address concerns about safety and lifestyle. Automated BAs may help people using MDI to manage their diabetes more effectively and minimise the risk of long-term diabetes related complications. Findings from a recent study suggest that BA use positively addresses both safety and lifestyle concerns; however, randomised trials are needed to confirm these perceptions and determine whether bolus advisor use improves clinical outcomes. Our study is designed to make these assessments. TRIAL REGISTRATION: NCT0146044
Looking for pulsations in HgMn stars through CoRoT lightcurves
HgMn Chemically Peculiar stars are among the quietest stars of the
main-sequence. However, according to theoretical predictions, these stars could
have pulsations related to the very strong overabundances of iron peak
elements, which are produced by atomic diffusion in upper layers. Such
pulsations have never been detected from ground based observations.
Our aim is to search for signatures of pulsations in HgMn stars using the
high quality lightcurves provided by the CoRoT satellite.
We identified three faint stars (V>12), from VLT-GIRAFFE multiobject
spectrograph survey in a field which was planned for observation by CoRoT. They
present the typical characteristics of HgMn stars. They were observed by the
CoRoT satellite during the long run (131 days) which started from the 24th of
October 2007, with the exoplanets CCD's (Additional Programme). In the present
work, we present the analysis of the ground based spectra of these three stars
and the analysis of the corresponding CoRoT lightcurves.
Two of these three HgMn candidates show low amplitude (less than 1.6 mmag)
periodic variations (4.3 and 2.53 days respectively, with harmonics) which are
compatible with periods predicted by theoretical models.Comment: Accepted paper in A&A (7 May 2009
A Potential Supernova Remnant/X-ray Binary Association in M31
The well-studied X-ray/Optical/Radio supernova remnant DDB 1-15 (CXOM31
J004327.8+411829; r3-63) in M31 has been investigated with archival XMM-Newton
and Chandra observations. The timing data from XMM-Newton reveals a power
density spectrum (PDS) characteristic of accreting compact objects in X-ray
binaries (XRBs). The PDS shows features typical of Roche lobe overflow
accretion, hinting that the XRB is low-mass. The Chandra observations resolve
the SNR into a shell and show a variable count rate at the 94% confidence level
in the northwest quadrant. Together, these XMM-Newton and Chandra data suggest
that there is an XRB in the SNR r3-63 and that the XRB is located in the
northwestern portion of the SNR. The currently-available X-ray and optical data
show no evidence that the XRB is high-mass. If the XRB is low-mass, r3-63 would
be the first SNR found to contain a low-mass X-ray binary.Comment: 30 pages, 3 tables, 11 figures, accepted for publication in Ap
Optimal column density measurements from multiband near-infrared observations
We consider from a general point of view the problem of determining the
extinction in dense molecular clouds. We use a rigorous statistical approach to
characterize the properties of the most widely used optical and infrared
techniques, namely the star count and the color excess methods. We propose a
new maximum-likelihood method that takes advantage of both star counts and star
colors to provide an optimal estimate of the extinction. Detailed numerical
simulations show that our method performs optimally under a wide range of
conditions and, in particular, is significantly superior to the standard
techniques for clouds with high column-densities and affected by contamination
by foreground stars.Comment: 20 pages; A&A in pres
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