24,697 research outputs found
Evolutionary Relationships of Courtship Songs in the Parasitic Wasp Genus, Cotesia (Hymenoptera: Braconidae)
Acoustic signals play an important role in premating isolation based on sexual selection within many taxa. Many male parasitic wasps produce characteristic courtship songs used by females in mate selection. In Cotesia (Hymenoptera: Braconidae: Microgastrinae), courtship songs are generated by wing fanning with repetitive pulses in stereotypical patterns. Our objectives were to sample the diversity of courtship songs within Cotesia and to identify underlying patterns of differentiation. We compared songs among 12 of ca. 80 Cotesia species in North America, including ten species that have not been recorded previously. For Cotesia congregata, we compared songs of wasps originating from six different host-foodplant sources, two of which are considered incipient species. Songs of emergent males from wild caterpillar hosts in five different families were recorded, and pattern, frequency, and duration of song elements analyzed. Principal component analysis converted the seven elements characterized into four uncorrelated components used in a hierarchical cluster analysis and grouped species by similarity of song structure. Species songs varied significantly in duration of repeating pulse and buzz elements and/or in fundamental frequency. Cluster analysis resolved similar species groups in agreement with the most recent molecular phylogeny for Cotesia spp., indicating the potential for using courtship songs as a predictor of genetic relatedness. Courtship song analysis may aid in identifying closely related cryptic species that overlap spatially, and provide insight into the evolution of this highly diverse and agriculturally important taxon
Adult pedestrian behavior when accompanying children on the route to school
Objective: Pedestrian injuries are a major cause of morbidity and mortality to children, especially boys. Adults serve as pedestrian role models and provide learning opportunities for children when walking to school. The research objectives were to investigate adult pedestrian behavior when accompanying boys and girls.
Methods: Behavioral observation of 140 adult pedestrians accompanying 4- to 9-year-old children was done in British residential locations. Observations took place at light-controlled crossings, speed-restricted school safety zones, and mid-block unmarked crossing sites. Behaviors observed included stopping at the curb, waiting at the curb, looking left and right before and during road crossing, holding hands, talking, and walking straight across.
Results: In general, adults modeled safe road crossing behaviors. Adult safe behavior scores were higher when accompanying girls than when accompanying boys. No statistically significant differences were found by child age group. The fewest safe pedestrian behaviors were observed at light-controlled crossings.
Conclusions: Adult pedestrians behave differently when with boys and girls and at different types of road crossing site. Interventions aimed at reducing pedestrian injuries to children may need to take these different everyday experiences into consideration
Shaping the future for primary care education and training project. Best practise in education and training strategies for integrated health and social care: development of a benchmarking tool
Collaboration and partnership working between Higher Education and the NHS is an essential requirement for
effective delivery of care (Universities UK 2003). The North West Universities Association (NWUA) and the North
West Development Agency (NWDA) are two organisations at the forefront of creating such alliances. The
research project, Shaping the Future for Primary Care Education and Training Project is a collaborative
partnership between both these organisations and seven North West Higher Education Institutions. In addition,
the project brings together for the first time all the key partners in the health, social care and education sectors
who are involved in supporting the delivery of integrated health and social care in the North West Region
The Impact of Distance Uncertainties on Local Luminosity and Mass Functions
In order to investigate discrepancies between recent published estimates of
the the HI mass function (HIMF), we explore the impact of distance
uncertainties on the derivation of the faint end slope of mass and luminosity
functions of galaxies in the local volume by deriving HIMFs from mock HI
surveys. We consider various survey geometries and depths and compare the HIMFs
measured when using ``real'' distances, distances derived by assuming pure
Hubble flow and distances assigned from parametric models of the local velocity
field. The effect is variable and dependent on the exact survey geometry, but
can easily lead to incorrect estimates of the HIMF, particularly at the low
mass end. We show that at least part of the discrepancies among recent
derivations of the HIMF can be accounted for by the use of different methods to
assign distances. We conclude that a better understanding of the local velocity
field will be necessary for accurate determinations of the local galaxy
luminosity and mass functions.Comment: 4 pages, accepted to ApJ
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