Impact of Secondary Acceleration in Gamma-Ray Bursts

We discuss the acceleration of secondary muons, pions, and kaons in gamma-ray bursts within the internal shock scenario, and their impact on the neutrino fluxes. We introduce a two-zone model consisting of an acceleration zone (the shocks) and a radiation zone (the plasma downstream the shocks). The acceleration in the shocks, which is an unavoidable consequence of the efficient proton acceleration, requires efficient transport from the radiation back to the acceleration zone. On the other hand, stochastic acceleration in the radiation zone can enhance the secondary spectra of muons and kaons significantly if there is a sufficiently large turbulent region. Overall, it is plausible that neutrino spectra can be enhanced by up to a factor of two at the peak by stochastic acceleration, that an additional spectral peaks appears from shock acceleration of the secondary muons and pions, and that the neutrino production from kaon decays is enhanced. Depending on the GRB parameters, the general conclusions concerning the limits to the internal shock scenario obtained by recent IceCube and ANTARES analyses may be affected by up to a factor of two by secondary acceleration. Most of the changes occur at energies above 10^7 GeV, so the effects for next-generation radio-detection experiments will be more pronounced. In the future, however, if GRBs are detected as high-energy neutrino sources, the detection of one or several pronounced peaks around 10^6 GeV or higher energies could help to derive the basic properties of the magnetic field strength in the GRB.Comment: 10 pages, 5 figures, 1 tabl

Human Activities and Global Environmental Changes: Implications for the People and Landscapes of the Tibetan Plateau

This paper challenges the commonly held Western perception that the people and landscapes are similar across the entire Tibetan Plateau region... Article abstract, p. 2

Death in the City of Light : The Culture of Death in Paris from the Middle Ages through the Nineteenth Century

Senior Project submitted to The Division of Languages and Literature of Bard College

Labour Market Status at Ages 50–64 and All-Cause Mortality at Ages 65–70: A Longitudinal Study from Finland

Individuals’ labour market status and health are known to be highly correlated. To investigate this association beyond prime working ages, we study how all-cause mortality at ages 65–70 relates to different labour market positions at ages 50–64. The data stem from random samples of the Finnish population, which make it possible to follow 33,000 individuals in the period 1987–2011. Hazard models are estimated to quantify the associations. For both men and women, disability pensioners have a hazard of dying at age 65+ that is approximately twice that of persons who were employed, and this ratio still exceeds 1.5 when socioeconomic and demographic variables are included. Also male unemployment, but not female, is associated with an elevated mortality risk, but this interrelation depends greatly on socioeconomic position

DNP Proposal: Delirium Prevention Protocol

Purpose and Rationale: To implement a delirium prevention (DP) sleep protocol to at risk intensive care unit (ICU) patients to reduce delirium incidence and duration. Synthesis of Evidence: A review of one clinical practice guideline, eight systematic reviews and meta-analysis, four randomized controlled trials, nine quasi-experimental trials, and one qualitative study provided evidence that interventions targeted to improve patients’ sleep may decrease delirium incidence and duration in adult patients in the ICU

Obstacles to Graduation: A Look at Poverty’s Effect on Academic Work

Our presentation was aimed at providing a thorough overview of concepts that interfere with an adolescent’s ability to stay in school and graduate. Additionally, the presentation addressed what other factors of poverty, such as risk-taking behaviors (e.g., marijuana use, binge drinking, or sexual activity), might carry over into college life and affect a student’s academic career. Variables connected to family community, family responsibilities, and adolescents’ self-esteem were described as well. Finally, the presentation discussed factors that play into a student’s willingness to seek out college campus resources for support. With this paper, we hope to outline variables that lead to academic drawbacks within our youth and to raise awareness about the multi-faceted phenomenon of retention of students

Dating furniture and coopered vessels without waney edge – Reconstructing historical wood-working in Austria with the help of dendrochronology

AbstractIn the present study, 208 furniture and 168 coopered vessels from three Austrian museums were examined. Dendrochronology was used to date objects and to extract further information such as the necessary time for seasoning, wood loss through wood-working and methods of construction. In most cases sampling was done by sanding the cross section and making digital photographs using a picture frame and measuring digitally.The dendrochronological dates of the sampled furniture range between 1524 and 1937. The group of furniture includes cupboards, chests, tables, benches, commodes and beds. In many cases furniture was artfully painted and sometimes even shows a painted year. With the help of dendrochronology it was proved that some objects had been painted for some time after construction, or had been over-painted. Most furniture, however, was painted immediately after completion. In this case, the seasoning and storage time of the boards and the wood loss due to shaping can be verified. As an average value, 14 years have passed between the dendrochronological date of the outermost ring and the painting. The time span includes time of seasoning and storage and the rings lost by wood-working. This leads, on the one hand to a short storage time of less than 10 years and on the other hand to very little wood loss due to manufacturing. Those boards being less shaped turned out to be back panels of cupboards, therefore they are recommended to be sampled for dating.Coopered vessels were dated between 1612 and 1940. There was evidence that staves were split and not sawn in many cases. The staves were often split out of the outermost part of the tree and hardly any wood was worked away which was proved by the close dendrochronological dates of the single staves of a vessel.Since there is a short time of storage and only little wood loss through wood-working, dating of objects without a waney edge becomes reasonable