3,161 research outputs found
On the second homology group of the Torelli subgroup of Aut(F_n)
Let IA_n be the Torelli subgroup of Aut(F_n). We give an explicit finite set
of generators for H_2(IA_n) as a GL_n(Z)-module. Corollaries include a version
of surjective representation stability for H_2(IA_n), the vanishing of the
GL_n(Z)-coinvariants of H_2(IA_n), and the vanishing of the second rational
homology group of the level l congruence subgroup of Aut(F_n). Our generating
set is derived from a new group presentation for IA_n which is infinite but
which has a simple recursive form.Comment: 39 pages; minor revision; to appear in Geom. Topo
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Steering drift and wheel movement during braking: static and dynamic measurements
YesThis paper reports on an experimental investigation into braking-related steering drift in
motor vehicles, and follows on from a previous paper by the authors in which it was concluded that
braking can cause changes in wheel alignment that in turn affect the toe-steer characteristics of each
wheel and therefore the straight-line stability of the vehicle during braking. Changes in suspension
geometry during braking, their magnitude and the relationships between the braking forces and the
suspension geometry and compliance are further investigated in an experimental study of wheel
movement arising from compliance in the front suspension and the steering system of a passenger
car during braking. Using a kinematic and compliance (K&C) test rig, movement of the front wheels
and the suspension subframe, together with corresponding changes in suspension and steering
geometry under simulated braking conditions, have been measured and compared with dynamic
measurements of the centre points of the front wheels. The results have enabled the causes and effects
of steering drift during braking to be better understood in the design of front suspension systems for
vehicle stability during braking
A Birman exact sequence for the Torelli subgroup of Aut(F_n)
We develop an analogue of the Birman exact sequence for the Torelli subgroup
of Aut(F_n). This builds on earlier work of the authors who studied an analogue
of the Birman exact sequence for the entire group Aut(F_n). These results play
an important role in the authors' recent work on the second homology group of
the Torelli group.Comment: 31 pages, minor revision; to appear in Int. J. Algebr. Compu
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Wheel movement during braking
YesAn experimental study of wheel movement arising from compliance in the front suspension and
steering system of a passenger car during braking is presented. Using a Kinematic and
Compliance (K&C) test rig, movement of the front wheels and the suspension sub-frame,
together with corresponding changes in suspension / steering geometry under simulated braking
conditions, were measured and compared with dynamic measurements of the centre points of the
front wheels. The resulting knowledge of front wheel deflections has enabled the causes and
effects of steering drift during braking to be better understood in the design of front suspension
systems for vehicle stability
Current trends in the rehabilitation of juvenile offenders
The Australian Institute of Criminology\u27s recent work on adult male offenders has found that the most serious and persistent adult offenders had been detained as a juvenile. In terms of crime reduction, interventions that focus on reducing the likelihood of juveniles escalating to adult offenders will have significant benefits for the whole of the Australian community. Research conducted in juvenile justice settings around the world consistently shows that young people who come to the attention of criminal justice agencies have multiple problems and experience high levels of need across all areas of functioning. In meeting these needs, correctional agencies have been increasingly influenced by the model of rehabilitation known as the \u27what works\u27 approach. This paper outlines a case management framework for rehabilitating juvenile offenders that includes three of the most important \u27what works\u27 principles, namely the risk principle, the needs principle and the responsivity principle. In the longer term, the implementation of the framework will need to be evaluated to determine what works and what doesn\u27t with rehabilitating juveniles.<br /
Prison officer\u27s beliefs regarding self-harm in prisoners : an empirical investigation
The prevention of self-harm and suicide in prisoners depends on good interaction between the individual prisoner and prison staff. Staff perceptions of prisoner self-harm are likely to be a crucial factor influencing this interaction. The aim of the present study was to determine correctional officers\u27 perception of the causes and functions of self-harm, and the effects of incident severity and repetitiveness on perceptions. A sample of 76 correctional officers was presented with a vignette depicting a self-harm in which the severity and repetitiveness of the incident was systematically altered. Officers\u27 rated both the causes and functions of the behaviour. Four attributional dimensions were identified by factor analysis. These factors related primarily to personal factors about the individual prisoner. Staff perceived the functions of self-harm to be communicative rather than to commit suicide. Perceptions were not affected by severity or repetitiveness information, except for high severity leading to a greater perception of suicidal intent. Initiatives to help staff work more effectively and therapeutically with distressed prisoners are therefore likely to impact positively upon rates of self-harm.<br /
Coeliac disease: where are we in 2014?
Presents up-to-date information on coeliac disease, with recommendations on whom to test and how to test them, and how to manage patients once they are diagnosed.
Summary
Background
Coeliac disease (CD) is an autoimmune condition affecting at least 1% of the population, many of whom remain undiagnosed. It is characterised by chronic inflammation of the small-intestinal mucosa and triggered by eating gluten. It is challenging to diagnose because of the many and varied ways in which it may present.
Discussion
Primary care practitioners have a crucial role in improving rates of CD diagnosis, and in the ongoing care of patients with CD. A blood test for coeliac-specific antibodies will identify most patients who need to undergo duodenal biopsy to make the diagnosis. Management encompasses supporting patients with adherence to the gluten-free diet and conducting a CD-focused clinical review every 1–2 years
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