2,600 research outputs found
Measurement of complex fragments and clues to the entropy production from 42-137-MeV/nucleon Ar + Au
Intermediate-rapidity fragments with A=1-14 emitted from 42-137-MeV/nucleon Ar + Au have been measured. Evidence is presented that these fragments arise from a common moving source. Entropy values are extracted from the mass distributions by use of quantum statistical and Hauser-Feshbach theories. The extracted entropy values of S/A≈2-2.4 are much smaller than the values expected from measured deuteron-to-proton ratios, but are still considerably higher than theoretically predicted values
Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data
Drivers need sufficient passing sight distance (PSD) to pass slower vehicles with safety. This distance can help to improve traffic operation on two-way, two-lane highways. Existing models propose different values of PSD because of different assumptions. In only some cases were these models based on field data of passing maneuvers. This research proposed the design of a methodology to observe passing maneuvers on existing highways with the help of six video cameras installed at a fixed point next to passing sections. The use of more cameras allows complete registration of trajectories along the entire passing zone, with uniform image resolution. The methodology was applied to register a sample of 234 maneuvers on four passing zones. Trajectories of 58 maneuvers were completely described and analyzed with specific restitution software. Results were compared with those from existing PSD models. The distances traveled proposed by the AASHTO model on the left lane were (a) similar to average observed distances when the passed vehicle was one truck and (b) between 50 and 100 m higher when one passenger car was passed. Higher differences, greater than 100 m, were found between measured data and the PSD model (published previously), especially at high design speeds. The observed average speed difference between passing and impeding vehicles was significantly higher than that in any model. Variables with the strongest influence on the time and distance traveled on the opposing lane were the type and speed of the passed vehicle and the length of the passing zone. Left-lane time and distance increase with this length.Llorca Garcia, C.; GarcĂa GarcĂa, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record. 2262:42-51. doi:10.3141/2262-05S42512262Farah, H., Bekhor, S., & Polus, A. (2009). Risk evaluation by modeling of passing behavior on two-lane rural highways. Accident Analysis & Prevention, 41(4), 887-894. doi:10.1016/j.aap.2009.05.006Rilett, L. R., Hutchinson, B. G., & Whitney, M. (1990). Mechanics of the passing maneuver and the impact of large trucks. Transportation Research Part A: General, 24(2), 121-128. doi:10.1016/0191-2607(90)90019-3Wang, Y., & Cartmell, M. P. (1998). New Model for Passing Sight Distance on Two-Lane Highways. Journal of Transportation Engineering, 124(6), 536-545. doi:10.1061/(asce)0733-947x(1998)124:6(536)Polus, A., Livneh, M., & Frischer, B. (2000). Evaluation of the Passing Process on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 53-60. doi:10.3141/1701-07Carlson, P., Miles, J., & Johnson, P. (2006). Daytime High-Speed Passing Maneuvers Observed on Rural Two-Lane, Two-Way Highway: Findings and Implications. Transportation Research Record: Journal of the Transportation Research Board, 1961, 9-15. doi:10.3141/1961-02Harwood, D. W., Gilmore, D. K., & Richard, K. R. (2010). Criteria for Passing Sight Distance for Roadway Design and Marking. Transportation Research Record: Journal of the Transportation Research Board, 2195(1), 36-46. doi:10.3141/2195-0
Kinetics of low-density lipoprotein receptor activity in Hep-G2 cells: derivation and validation of a BriggsâHaldane-based kinetic model for evaluating receptor-mediated endocytotic processes in which receptors recycle
A Record of Antarctic Climate and Ice Sheet History Recovered
Antarcticaâs late Cenozoic (the past ~15 million years) climate history is poorly known from direct evidence, owing to its remoteness, an extensive sea ice apron, and an ice sheet cover over the region for the past 34 million years. Consequently, knowledge about the role of Antarcticaâs ice sheets in global sea level and climate has relied heavily upon interpretations of oxygen isotope records from deep-sea cores. Whereas these isotopic records have revolutionized our understanding of climate-ice-ocean interactions, questions still remain about the specific role of Antarctic ice sheets in global climate. Such questions can be addressed from geological records at the marine margin of the ice sheets, recovered by drilling from floating ice platforms [e.g., Davey et al., 2001; Harwood et al., 2006; Barrett, 2007].
During the austral summer of 2006â2007, a new Antarctic geological drilling program (ANDRILL) successfully recovered a 1285- meter-long record of climate and ice sheet variability spanning the past 13 million years from beneath the McMurdo Ice Shelf (Figure 1). The cores contain sedimentary rocks deposited by the ice sheets grounded in the sea, and they provide the best direct evidence to date of past Antarctic ice sheet and climate fluctuations for this period of Earthâs history.
The new geological evidence is being used to provide direct physical calibrationfor deep-sea isotope records, low-latitude continental margin sea level records, and numerical climate and ice sheet models, especially for times of past global warmth. Such analogs are becoming increasingly important because of the difficulties in predicting the dynamic response of ice sheets to global warming [Vaughan and Athern, 2007]. In this article we summarize the initial results of the ANDRILL programâs first drilling project from the McMurdo Ice Shelf (MIS) site [Naish et al., 2007a, 2007b], with an emphasis on the potential of the record for improving our knowledge of Antarcticaâs influence on, and response to, global climate change
An investigation into CLIL-related sections of EFL coursebooks : issues of CLIL inclusion in the publishing market
The current ELT global coursebook market has embraced CLIL as a weak form of bilingual education and an innovative component to include in General English coursebooks for EFL contexts. In this paper I investigate how CLIL is included in ELT coursebooks aimed at
teenaged learners, available to teachers in Argentina. My study is based on the content analysis of four series which include a section advertised as CLIL-oriented. Results suggest that such sections are characterised by (1) little correlation between featured subject specific content and school curricula in L1, (2) oversimplification of contents, and (3) dominance of reading skills development and lower-order thinking tasks. Through this study, I argue that
CLIL components become superficial supplements rather than a meaningful attempt to promote weak forms of bilingual education
Modelling the population size and dynamics of the British grey seal
Funding: part-funded by the UK Natural Environment Research Council to SMRU (Grant no. SMRU1001).1. Grey seals (Halichoerus grypus) were the first mammals to be protected by an Act of Parliament in the UK and are currently protected under UK, Scottish, and EU conservation legislation. Reporting requirements under each of these statutes requires accurate and timely population estimates. Monitoring is principally conducted by aerial surveys of the breeding colonies; these are used to produce estimates of annual pup production. Translating these data to estimates of adult population size requires information about demographic parameters such as fecundity and sex ratio. 2. An ageâstructured population dynamics model is presented, which includes density dependence in pup survival, with separate carrying capacities in each of the four breeding regions considered (North Sea, Inner Hebrides, Outer Hebrides, and Orkney). This model is embedded within a Bayesian stateâspace modelling framework, allowing the population model to be linked to available data and the use of informative prior distributions on demographic parameters. A computerâintensive fitting algorithm is presented based on particle filtering methods. 3. The model is fitted to regionâlevel pup production estimates from 1984 to 2010 and an independent estimate of adult population size, derived from aerial surveys of hauledâout seals in 2008. The fitted model is used to estimate total population size from 1984 to 2010. 4. The population in the North Sea region has increased at a nearâconstant rate; growth in the other three regions began to slow in the midâ1990s and these populations appear to have reached carrying capacity. The total population size of seals aged 1 year or older in 2010 was estimated to be 116 100 (95% CI 98 400â138 600), an increase of <1% on the previous year. 5. The modelling and fitting methods are widely applicable to other wildlife populations where diverse sources of information are available and inference is required for the underlying population dynamics.PostprintPeer reviewe
LOFAR MSSS: The Scaling Relation between AGN Cavity Power and Radio Luminosity at Low Radio Frequencies
This article has been accepted for publication in a forthcoming issue of Astronomy & Astrophysics. Reproduced with permission from Astronomy & Astrophysics. © 2018 ESO.We present a new analysis of the widely used relation between cavity power and radio luminosity in clusters of galaxies with evidence for strong AGN feedback. We study the correlation at low radio frequencies using two new surveys - the First Alternative Data Release of the TIFR GMRT Sky Survey (TGSS ADR1) at 148 MHz and LOFAR's first all-sky survey, the Multifrequency Snapshot Sky Survey (MSSS) at 140 MHz. We find a scaling relation , with a logarithmic slope of , which is in good agreement with previous results based on data at 327 MHz. The large scatter present in this correlation confirms the conclusion reached at higher frequencies that the total radio luminosity at a single frequency is a poor predictor of the total jet power. We show that including measurements at 148 MHz alone is insufficient to reliably compute the bolometric radio luminosity and reduce the scatter in the correlation. For a subset of four well-resolved sources, we examine the detected extended structures at low frequencies and compare with the morphology known from higher frequency images and Chandra X-ray maps. In Perseus we discuss details in the structures of the radio mini-halo, while in the 2A 0335+096 cluster we observe new diffuse emission associated with multiple X-ray cavities and likely originating from past activity. For A2199 and MS 0735.6+7421, we confirm that the observed low-frequency radio lobes are confined to the extents known from higher frequencies. This new low-frequency analysis highlights the fact that existing cavity power to radio luminosity relations are based on a relatively narrow range of AGN outburst ages. We discuss how the correlation could be extended using low frequency data from the LOFAR Two-metre Sky Survey (LoTSS) in combination with future, complementary deeper X-ray observations.Peer reviewe
From toothpick legs to dropping vaginas: Gender and sexuality in Joan Rivers' stand-up comedy performance
This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2011 Intellect.This article employs sociocultural analysis to examine Joan Riversâ stand-up comedy performances in order to reveal how she successfully operates in a sphere of artistic expression that has been, and continues to be, male-dominated. The analysis uncovers how Riversâ stand-up comedy performance involves a complex combination of elements and how it fuses features that are regarded as âtraditionally masculineâ, such as aggression, with features frequently used by other female stand-up comedians, such as self-deprecating comedy and confessional comedy. Furthermore, the analysis exposes the complex ways in which constructions of gender and sexuality are negotiated and re-negotiated in Riversâ stand-up comedy performance, and illustrates how dominant ideological identity constructions can be simultaneously reinforced and subverted within the same comic moment
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