Transient Fragments in Outbursting Comet 17P/Holmes

We present results from a wide-field imaging campaign at the Canada-France-Hawaii Telescope to study the spectacular outburst of comet 17P/Holmes in late 2007. Using image-processing techniques we probe inside the spherical dust coma and find sixteen fragments having both spatial distribution and kinematics consistent with isotropic ejection from the nucleus. Photometry of the fragments is inconsistent with scattering from monolithic, inert bodies. Instead, each detected fragment appears to be an active cometesimal producing its own dust coma. By scaling from the coma of the primary nucleus of 17P/Holmes, assumed to be 1.7 km in radius, we infer that the sixteen fragments have maximum effective radii between ~ 10 m and ~ 100 m on UT 2007 Nov. 6. The fragments subsequently fade at a common rate of ~ 0.2 mag/day, consistent with steady depletion of ices from these bodies in the heat of the Sun. Our characterization of the fragments supports the hypothesis that a large piece of material broke away from the nucleus and crumbled, expelling smaller, icy shards into the larger dust coma around the nucleus.Comment: 41 pages, 12 figures. Accepted for publication by the Astronomical Journal

Eu(rope): (re)assembling, (re)casting and (re)aligning lines of de- and re-territorialisation of early childhood

The aim of this paper is to (re)(e)value(ate) current micro-and macropolicies and politics that shape – and are shaped by – conceptualisations of and, in consequence, practices towards young children in a range of institutions/figurations. The 'geopolitical' location for our investigation is Europe, understood as conceptual space(s) as well as (geographical) territory. Whilst we begin by focusing attention on events within an English context, we nevertheless move beyond geographical boundaries. We argue that movements that are currently being undertaken in England are not individual activities. Rather, England is infected and affected by European and global histories, practices, policies, philosophies and epistemologies. We argue that it is the oscillations between different components within a broad European assemblage (human and nonhuman) that makes something happen. Subsequently, we detail and question whether 'happenings' that are occurring in England can be considered as possible creative openings where early childhood education/care could be reassembled 'differently'. Once one steps outside what's been thought before . . . once one ventures outside what's familiar and reassuring, once one has to invent new concepts for unknown lands, then methods and moral systems break down and thinking becomes, as Foucault puts it, a ''perilous act'', a violence, whose first victim is oneself

Cavity Enhancement of Single Quantum Dot Emission in the Blue.

Cavity-enhanced single-photon emission in the blue spectral region was measured from single InGaN/GaN quantum dots. The low-Q microcavities used were characterized using micro-reflectance spectroscopy where the source was the enhanced blue output from a photonic crystal fibre. Micro-photoluminescence was observed from several cavities and found to be ~10 times stronger than typical InGaN quantum dot emission without a cavity. The measurements were performed using non-linear excitation spectroscopy in order to suppress the background emission from the underlying wetting layer.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Predictors of Casual Sex Participation in Young Adulthood: Evidence from the National Longitudinal Study of Adolescent Health

Casual sex is often associated with young adulthood. Most research on the prevalence of casual sex has relied on college students and regional samples. The current study utilized the third wave of the National Longitudinal Study of Adolescent Health, which was collected in 2001-2002, to obtain nationally representative estimates of the prevalence of casual sex for young adults between the ages of 18-24. This study replicates Lyons and colleagues’ (2013) work on the associations between varying educational trajectories and young adult casual sex behavior, and moves beyond prior work by examining recent casual sex and recent casual oral sex participation. The results suggested that young adults with some college experience or a community college experience were more likely to report casual sex participation within the past 6 months, compared to young adults with a Bachelor’s degree or who were enrolled in a 4-year post-secondary institution. Contrary to Lyons et al.’s (2013) findings, the results also indicated an interaction effect between gender and education status, such that the differences between recent casual sex participation and education status were significant only for men. These results may be helpful for programs aimed at encouraging healthy sexual behavior to identify young adults groups who have the highest risk of casual sex partners

Sky Patterns [2nd grade]

This unit will give students the opportunity to observe, describe, illustrate and predict patterns found in nature and specifically the daytime and nighttime sky. The students will build on their prior knowledge of objects found in daytime and nighttime sky. Students will practice gathering, recording, and discussing data through classroom and home investigations leading to understandings of patterns found in nature. Using the data and findings, the student will create projects displaying their understanding of patterns found in the daytime and nighttime sky

Red, white and blue highways: British travel writing and the American road trip in the late twentieth century

This study locates late-twentieth-century roadlogues (nonfiction, prose accounts of American road trips) by British writers within the tradition of the postwar American highway narrative in travel writing, novels, and film. It exposes the discursive structures and textual constraints underlying seven case studies published in the 1990s by comparing them to texts from various genres in diachronic and synchronic contexts. It contributes to scholarship on the American highway narrative, which largely overlooks British texts. It complements research on British travel writing, which tends to be biased towards pre-twentieth-century texts by travellers whose culture is in a dominant relation to that of travellees. It adds to postcolonial studies through analysis of representations of the other where otherness is reduced and complicated by a history of cultural exchange. The methodology combines several approaches including discourse theory, discourse analysis, narrative theory, feminist criticism, and theories of tourism. Three main areas are considered: identity, in relation to nationality and gender; the road writer's gaze, with regard to vehicles and roads; and intertextuality, on the margins (in maps) and inside roadlogues (in direct and indirect allusions). The study concludes that contemporary British roadlogues are in what is almost a subordinate relation to American highway narratives, evidenced by extensive influence of American texts. However, this subordination is qualified by joint ownership of western and New World myths, vestiges of imperial superiority, and selective deference by British writers. The latter is demonstrated through a consumer approach to American culture afforded by the episodic structure of the road trip and encouraged by the niche-oriented nature of the current market for travel writing. While American writers regard roadscapes with imperial eyes and experience the road trip as a rite of passage, contemporary Britons generally engage in superficial role play and remain untransformed by American highways

Obscurity and Gender Resistance in Patricia Duncker's James Miranda Barry

publication-status: Submittedtypes: Article© 2012 by Taylor & FrancisSince his death in 1865, military surgeon James Barry has alternately been classified as a cross-dressing woman or as an intersexed individual. Patricia Duncker’s novel James Miranda Barry (1999) poses an important challenge to such readings, as it does not reveal any foundational truth about Barry’s sex. Resting on obscurity rather than revelation, the text frustrates the desire to know the past in terms of gender binaries and stable sexual identity categories. Drawing on feminist and queer theorisations of the relation between gender and time, this essay demonstrates that Duncker’s use of obscurity opens up alternative strategies of gender resistance.The Wellcome Trus

Preliminary Results of Radiohalos from Four Sites of Precambrian Minnesota Granite

Radiohalo research is a relatively new area of scientific investigation, the significance of which has been shown by authors such as Snelling and Gentry. This study examines the prevalence of the radiohalos of polonium isotopes and uranium isotopes within biotite flakes generated by radioactive zircon crystals. The radiohalos result from damage caused by the emanation of hundreds of millions of alpha particles from the zircon crystals during the decay process. The samples were obtained from drill cores granted to us by the Drill Core Library in Hibbing, Minnesota. The Precambrian granite core sections were crushed and small biotite flakes picked out. The “Scotch tape” method was used to separate the many layers of biotite flakes which were then placed on glass slides and analyzed under the microscope. Center radiohalos were marked, taken a picture of using the petrographic microscope, measured, and logged. We prepared forty slides per sample with biotite flakes scattered across each slide. We found thirty-eight radiohalos total in MN-1; roughly thirty-five radiohalos total in MN-2A; five radiohalos total in MN-2B; and seventeen radiohalos total MN-3A. All of the radiohalos contain either holes or zircons at their center and majority appear to be made from polonium. These are initial results and further analysis will continue to be conducted. This study contributes to a larger study of Precambrian granite with a focus on Minnesota core samples