2,439 research outputs found
A case study of argumentation at undergraduate level in history
This article examines two essays by undergraduate students in the first year of study in History at a university in the UK. It also draws on documentary evidence from the department in question and interviews with the students themselves to paint a picture of the way argumentation operates at this level. While no firm conclusions can be drawn, the evidence suggests a department with a high degree of awareness of the importance of argument and argumentation in studying History; and students who are aware and articulate about the problem facing them in constructing essays in the discipline. Suggestions are made about induction into the epistemological and argumentative demands of undergraduate study
Evaluating the use of lecture capture using a revealed preference approach
This article discusses the introduction of lecture capture technology on a large undergraduate module with diverse student cohorts. Literature has so far relied on surveying students to discover their use of the technology or attempted to quantify the impact of watching lecture recordings on assessment performance. Alternatively, the principal contribution of this article is an evaluation of the use of the recorded lectures using a revealed preference approach. Specifically we identify to what extent students watched lecture recordings, rather than simply claimed to watch them when asked to provide comments on the technology. Data indicates the number of distinct students who watched recordings, the frequency with which they watched recordings, the average length of viewings as well as the time of day when lectures were viewed. We monitored viewings over two academic years, identifying âspikesâ in the number of viewings in the days before tests, as well as regularities in the viewing patterns across the two years. We analyse the data to assess the extent to which students used the recordings, how and when they watched the recordings. We conclude that the students value lecture recordings, making more extensive use of the recordings than has been identified in the literature to date. Ultimately, lecture recordings are suggested to offer valuable support for studentsâ independent study
Monitoring summertime indoor overheating and pollutant risks and natural ventilation patterns of seniors in public housing
Indoor heat and air pollution pose concurrent threats to human health and wellbeing, and their effects are more pronounced for vulnerable individuals. This study investigates exposures to summertime indoor overheating and airborne particulate matter (PM2.5) experienced by low-income seniors and explores the potential of natural ventilation on maintaining good indoor thermal conditions and air quality (IAQ). Environmental and behavioural monitoring and a series of interviews were conducted during summer 2017 in 24 senior apartments on three public housing sites in NJ, USA (1930sâ low-rise, 1960sâ high-rise and LEED-certified 2010sâ mid-rise). All sites had high exposures to overheating and PM2.5 concentrations during heat waves and on regular summer days, but with substantial between-site and between-apartment variability. Overheating was higher in the 30sâ low-rise site, while pollutant levels were higher in the 60sâ high-rise. Mixed linear models indicated a thermal and air quality trade-off with window opening (WO), especially in some âsmokingâ units from the older sites, but also improved both thermal and PM2.5 concentration conditions in 20% of the apartments. Findings suggest that with warmer future summers, greater focus is needed on the interdependencies among (1) thermal and IAQ outcomes and (2) technological and behavioural dimensions of efforts to improve comfort for vulnerable occupants
'Why am I putting myself through this?' Women football coaches' experiences of the Football Association's coach education process
In recent years, there has been a significant increase in the provision of formal coach education. However, research has repeatedly demonstrated how coach education has had a limited impact on the learning and development of coach practitioners. To date however, these investigations have avoided female coach populations. Ten women football coaches who had recently completed various association football coach education courses participated in this study. Following the interpretive analysis of 10 semi-structured interviews the findings revealed high levels of gender discrimination and inappropriate cultural practice. The womenâs experiences are discussed in line with the Bourdieuian notions of social acceptance, symbolic language and power. The women coaches provided a number of recommendations for future coach education provision, which in turn, may help to improve the experiences for those women who participate in the coach education process
Gas Explosion Venting: External Explosion Turbulent Flame Speeds that Control the Overpressure
In most vented explosions the peak overpressure is controlled by turbulent flame propagation external to the vent. This has been known for many years, but a method to predict the overpressure from the external flame speed has not been developed. Current vent modelling is based on the assumption that the unburned gas flow through the vent controls the overpressure and does not address the issue of the external explosion. This work shows that the external flame speeds in a small vented explosion test facility can be predicted from Taylorsâs acoustic theory (1946). Vented explosion data is presented for vent coefficients from 3 â 22 for the most reactive mixtures of methane, propane and ethylene in terms of the overpressure and the external flame speed. The overpressure from Taylorsâs acoustic theory give a good prediction of the measured overpressure
Relative blocking in posets
Poset-theoretic generalizations of set-theoretic committee constructions are
presented. The structure of the corresponding subposets is described. Sequences
of irreducible fractions associated to the principal order ideals of finite
bounded posets are considered and those related to the Boolean lattices are
explored; it is shown that such sequences inherit all the familiar properties
of the Farey sequences.Comment: 29 pages. Corrected version of original publication which is
available at http://www.springerlink.com, see Corrigendu
Crack-Like Processes Governing the Onset of Frictional Slip
We perform real-time measurements of the net contact area between two blocks
of like material at the onset of frictional slip. We show that the process of
interface detachment, which immediately precedes the inception of frictional
sliding, is governed by three different types of detachment fronts. These
crack-like detachment fronts differ by both their propagation velocities and by
the amount of net contact surface reduction caused by their passage. The most
rapid fronts propagate at intersonic velocities but generate a negligible
reduction in contact area across the interface. Sub-Rayleigh fronts are
crack-like modes which propagate at velocities up to the Rayleigh wave speed,
VR, and give rise to an approximate 10% reduction in net contact area. The most
efficient contact area reduction (~20%) is precipitated by the passage of slow
detachment fronts. These fronts propagate at anomalously slow velocities, which
are over an order of magnitude lower than VR yet orders of magnitude higher
than other characteristic velocity scales such as either slip or loading
velocities. Slow fronts are generated, in conjunction with intersonic fronts,
by the sudden arrest of sub-Rayleigh fronts. No overall sliding of the
interface occurs until either of the slower two fronts traverses the entire
interface, and motion at the leading edge of the interface is initiated. Slip
at the trailing edge of the interface accompanies the motion of both the slow
and sub-Rayleigh fronts. We might expect these modes to be important in both
fault nucleation and earthquake dynamics.Comment: 19 page, 5 figures, to appear in International Journal of Fractur
Effective radiative forcing in a GCM with fixed surface temperatures
Effective radiative forcing (ERF) is evaluated in the ACCESS1.0 General Circulation Model (GCM) with fixed land and seaâsurfaceâtemperatures as well as seaâice. The 4xCO2 ERF is 8.0 Wmâ2. In contrast, a typical ERF experiment with only fixed seaâsurfaceâtemperatures (SST) and seaâice gives rise to an ERF of only 7.0 Wmâ2. This difference arises due to the influence of land warming in the commonly used fixedâSST ERF experimental design, which results in: (i) increased emission of longwave radiation to space from the land surface (â0.45 Wmâ2) and troposphere (â0.90 Wmâ2), (ii) reduced land snowâcover and albedo (+0.17 Wmâ2), (iii) increased waterâvapour (+0.49 Wmâ2), and (iv) a cloud adjustment (â0.26 Wmâ2) due to reduced stability and cloudiness over land (positive ERF) counteracted by increased lower tropospheric stability and marine cloudiness over oceans (negative ERF) . The sum of these radiative adjustments to land warming is to reduce the 4xCO2 ERF in fixedâSST experiments by âŒ1.0 Wmâ2. CO2 stomatal effects are quantified and found to contribute just over half of the land warming effect and adjustments in the fixedâSST ERF experimental design in this model. The basic physical mechanisms in response to land warming are confirmed in a solar ERF experiment. We test various methods that have been proposed to account for land warming in fixedâSST ERFs against our GCM results and discuss their strengths and weaknesses
The role of immune correlates of protection on the pathway to licensure, policy decision and use of group B Streptococcus vaccines for maternal immunization: considerations from World Health Organization consultations.
The development of a group B Streptococcus (GBS) vaccine for maternal immunization constitutes a global public health priority, to prevent GBS-associated early life invasive disease, stillbirth, premature birth, maternal sepsis, adverse neurodevelopmental consequences, and to reduce perinatal antibiotic use. Sample size requirements for the conduct of a randomized placebo-controlled trial to assess vaccine efficacy against the most relevant clinical endpoints, under conditions of appropriate ethical standards of care, constitute a significant obstacle on the pathway to vaccine availability. Alternatively, indirect evidence of protection based on immunologic data from vaccine and sero-epidemiological studies, complemented by data from opsonophagocytic in vitro assays and animal models, could be considered as pivotal data for licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations. Based on discussions initiated by the World Health Organization we present key considerations about the potential role of correlates of protection towards an accelerated pathway for GBS vaccine licensure and wide scale use. Priority activities to support progress to regulatory and policy decision are outlined
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