424 research outputs found
Geographical distribution and population structure of springbok <I>Antidorcas marsupialis</I> rumen protozoa in southern Africa
Springbok were sampled in Angola, South West Africa, Kalahari Gemsbok National Park, the Cape Province and Eastern Transvaal between July 1973 and July 1974. All the ciliates found in the 20 rumens investigated belonged to a single genus Entodinium (family Ophryoscolecidae) and they varied in number from 0,3 x 106 to 2,5 x 106 per cm3 of rumen fluid. The different species were found and a positive correlation is seen between total numbers and protein content of the feed. It has been concluded that the numbers of E. par-uum are closely related to the protein concentration of the feed
Hanging off a bar
Exertion Games involve physical effort and as a result can facilitate physical health benefits. We present Hanging off a Bar, an action hero-inspired Exertion Game in which players hang off an exercise bar over a virtual river for as long as possible. Initial observations from three events with audiences ranging from the general public to expert game designers suggest that Hanging off a Bar can be engaging for players and facilitate intense exertion within seconds. Furthermore, we collected suggestions for what game elements players believe could entice them to increase their physical effort investment. These suggestions, combined with Hanging off a Bar as research vehicle due to the easy measurement of exertion through hanging time, enable future explorations into the relationship between digital game elements and physical exertion, guiding designers on how to support exertion in digital game
Direct simulation of ion beam induced stressing and amorphization of silicon
Using molecular dynamics (MD) simulation, we investigate the mechanical
response of silicon to high dose ion-irradiation. We employ a realistic and
efficient model to directly simulate ion beam induced amorphization. Structural
properties of the amorphized sample are compared with experimental data and
results of other simulation studies. We find the behavior of the irradiated
material is related to the rate at which it can relax. Depending upon the
ability to deform, we observe either the generation of a high compressive
stress and subsequent expansion of the material, or generation of tensile
stress and densification. We note that statistical material properties, such as
radial distribution functions are not sufficient to differentiate between
different densities of amorphous samples. For any reasonable deformation rate,
we observe an expansion of the target upon amorphization in agreement with
experimental observations. This is in contrast to simulations of quenching
which usually result in denser structures relative to crystalline Si. We
conclude that although there is substantial agreement between experimental
measurements and most simulation results, the amorphous structures being
investigated may have fundamental differences; the difference in density can be
attributed to local defects within the amorphous network. Finally we show that
annealing simulations of our amorphized samples can lead to a reduction of high
energy local defects without a large scale rearrangement of the amorphous
network. This supports the proposal that defects in amorphous silicon are
analogous to those in crystalline silicon.Comment: 13 pages, 12 figure
Preliminary results of<i> in vitro </i>digestion of some plants utilized by Kalahari ungulates
Doing gender locally: The importance of ‘place’ in understanding marginalised masculinities and young men’s transitions to ‘safe’ and successful futures
Observable anxieties have been developing about the position of boys and young men in contemporary society in recent years. This is expressed as a crisis of masculinity, in which place is often implicitly implicated, but is rarely considered for its role in the shaping of young men’s practices, trajectories and aspirations. Drawing on research conducted with young people who accessed a range of social care support services, this article argues that transition means different things for young men in different locales and that local definitions of masculinity are required to better understand young men’s lives and the opportunities available to them. The authors argue that home life, street life, individual neighbourhoods, regions and nations all shaped the young men’s identities and the practices they (and the staff working with them) drew on in order to create successful futures and ‘safe’ forms of masculinity. It is suggested that this place-based approach has the potential to re-shape the ‘crisis’ discourse surrounding masculinity and the anxieties associated with young men
Training teachers for the multimedia age: developing teacher expertise to enhance online learner interaction and collaboration
This article considers the skills that enable teachers to foster interaction and collaboration in online language learning. Drawing on Hampel and Stickler’s (2005) skills pyramid for online language learning and teaching, it presents the pre-service and in-service training programme that associate lecturers in the Department of Languages at the Open University undergo in the context of teaching languages with the help of online communication tools. Two projects are presented that shed more light on the expertise required to teach languages in virtual learning environments. The first project highlights the skills that are needed to teach in a complex online environment; the second one, a teacher training study, aimed to examine distance teachers’ experience of facilitating online group work, identify development needs, try out the potential of specific asynchronous and synchronous tools to support collaborative learning and trial possible development activities. The paper concludes by describing the kind of training programme that tutors require in order to acquire the skills identified
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A Diagnostic Aid For Detecting Multiple Mental Disorders In Primary Care: The Symptom Driven Diagnostic System For Primary Care (sdds-pc*).
A high rate of undiagnosed mental disorders in primary care has been well documented for nearly three decades. (Shepherd et al 1966; Regier et al 1978,1993; Goldberg et al 1980; Van Hermert et al 1993; Olfson and Klerman, 1992; Barrett et al 1988). Failure to recognize mental illness has been shown to lead to undertreatment, greater impairment, and a longer duration of illness (Ormel et al 1991). The few efforts to change the diagnostic practice of primary care physicians, either through providing information from a patient screen completed prior to the physician visit or through physician education, have provided equivocal results. (Higgins 1994; Rand et al 1988; Goldberg 1980). The effects of improved physician recognition on decreasing patients’ health care use have also been equivocal, probably because there are many steps between recognition and patient outcome. These steps include accurate diagnosis, proper treatment, patient compliance, and timely follow-up with adjustment in treatment, as needed.
Efforts to improve detection of mental disorders have concentrated on developing patient screens, which usually includea list ofpsychiatric symptoms independent of specific diagnoses, (Goldberg et al 1980; Borgquist et al 1993; Von Korff et al 1987) or which screen for one diagnosis; depression or alcoholism (Selzer 1971; Babor et al 1992). The former approach is limited because symptoms are not directly related to a treatable disorder, the latter, because patients may have more than one treatable psychiatric disorder (Kessler et al 1994). Moreover, screens are not widely used in primary care (Nelson and Berwick, 1989). Because most primary care visits are 15 minutes long or less, there is a need to develop rapid assessment methods that can be incorporated into routine care (Barrett 1991; Mitchell et al 1988; Anderson and Mattsson 1989)
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