2,115 research outputs found
Do As I Say...Should We Teach Only Abstinence in Sex Education?
In order to address these problems more effectively, it is not necessary to settle any of thepolitical debates that whirl around the issue of sexuality education. What is needed is a commitment to results. Elected officials, teachers, school boards and parents need to choose: is the function of sexuality education in public schools primarily to prevent disease and unplanned pregnancy or to promote traditional ideology?We need to use the information currently available to set responsible sexuality educationpolicy focused on improved outcomes for youth. Quality research on program effectiveness, along with a close analysis of the needs of young people at especially high risk, provides important guidance
The K-band Hubble diagram for brightest cluster galaxies in X-ray clusters
This paper concerns the K band Hubble diagram for the brightest cluster
galaxies (BCGs) in a sample of X-ray clusters covering the redshift range
. We show that BCGs in clusters of high X-ray luminosity are
excellent standard candles: the intrinsic dispersion in the raw K band absolute
magnitudes of BCGs in clusters with erg
s (in the 0.3 - 3.5 keV band) is no more than 0.22 mag, and is not
significantly reduced by correcting for the BCG structure parameter, ,
or for X-ray luminosity. This is the smallest scatter in the absolute
magnitudes of any single class of galaxy and demonstrates the homogeneity of
BCGs in high- clusters. By contrast, we find that the brightest
members of low- systems display a wider dispersion ( mag)
in absolute magnitude than commonly seen in previous studies, which arises from
the inclusion, in X-ray flux-limited samples, of poor clusters and groups which
are usually omitted from low redshift studies of BCGs in optically rich
clusters....[abstract shortened].. The BCGs in our high- clusters
yield a value of if the cosmological constant
. For a flat Universe we find
with a 95 per cent confidence upper limit to the cosmological constant
corresponding to . These results are discussed in the
context of other methods used to constrain the density of the Universe, such as
Type Ia supernovae.Comment: Accepted for publication in MNRAS. 15 pages, 13 Postscript figs
included. Uses epsfig and mn.st
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River basin planning project: social learning (Science Report SC050037/SR1)
This report documents the findings of a 12-month Environment Agency science project on social learning for river basin planning. Our aim was to use social learning approaches and soft system methods to inform the development of the River Basin Planning Strategy and improve the effectiveness of the Environment Agency's Water Framework Directive (WFD) Programm
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Supporting Water Governance and Climate Change Adaptation Through Systemic Praxis
Understanding and working with multiple perspectives on issues of change is an essential part of managing “common pool” water resources. In uncertain and complex situations arising from changes in human settlements and climate, both lives and livelihoods can be at stake. One individual’s or group’s choices can adversely affect others and traditional processes of participation and legislation are often inadequate. Discourse on environmental law recognises that noncompliance with legislation is associated with weak national governance structures. A systemic approach to managing change is required to appreciate interconnections among issues at various levels and to mediate different stakeholdings. Yet there are no blueprints for effecting systemic transformations of complex situations. This paper explores how the implementation of climate change adaptation can be supported when grounded in situations, such as water governance. It draws on the authors’ experiences of systemic praxis in the water sector
Evaluating the Wiimote as a musical controller
The Nintendo Wiimote is growing in popularity with mu-sicians as a controller. This mode of use is an adaptationfrom its intended use as a game controller, and requiresevaluation of its functions in a musical context in orderto understand its possibilities and limits. Drawing on Hu-man Computer Interaction methodology, we assessed thecore musical applications of the Wiimote and designeda usability experiment to test them. 17 participants tookpart, performing musical tasks in four contexts: trigger-ing; precise and expressive continuous control; and ges-ture recognition. Interviews and empirical evidence wereutilised to probe the device’s limitations and its creativestrengths. This study should help potential users to planthe Wiimote’s employment in their projects, and should beuseful as a case study in HCI evaluation of musical con-trollers
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Partnerships for action in river catchment governance. A case study in the Irwell, UK.
Improving Outcomes: Blueprint for a National AIDS Plan for the United States
Calls for a national plan of action to address the AIDS epidemic in America. Recommends the development of clear objectives, identified responsibilities and timelines, and strategies to assess and refine public health efforts
Structured Training for Neural Network Transition-Based Parsing
We present structured perceptron training for neural network transition-based
dependency parsing. We learn the neural network representation using a gold
corpus augmented by a large number of automatically parsed sentences. Given
this fixed network representation, we learn a final layer using the structured
perceptron with beam-search decoding. On the Penn Treebank, our parser reaches
94.26% unlabeled and 92.41% labeled attachment accuracy, which to our knowledge
is the best accuracy on Stanford Dependencies to date. We also provide in-depth
ablative analysis to determine which aspects of our model provide the largest
gains in accuracy
Evolution in cluster cores since z~1
A large fraction of the stellar mass in galaxy clusters is thought to be
contained in the diffuse low surface brightness intracluster light (ICL). Being
bound to the gravitational potential of the cluster rather than any individual
galaxy, the ICL contains much information about the evolution of its host
cluster and the interactions between the galaxies within. However due its low
surface brightness it is notoriously difficult to study. We present the first
detection and measurement of the flux contained in the ICL at z~1. We find that
the fraction of the total cluster light contained in the ICL may have increased
by factors of 2-4 since z~1, in contrast to recent findings for the lack of
mass and scale size evolution found for brightest cluster galaxies. Our results
suggest that late time buildup in cluster cores may occur more through
stripping than merging and we discuss the implications of our results for
hierarchical simulations.Comment: To appear in the Proceedings of IAU Symposium 295 - The intriguing
life of massive galaxie
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