Energy Deposition along The Helical Undulator at ILC-250GeV

The positron source of the International Linear Collider is based on a superconducting helical undulator passed by the high-energy electron beam to generate photons which hit a conversion target. Since the photons are circularly polarized the resulting positron beam is polarized. At ILC250, the full undulator is needed to produce the required number of positrons. To keep the power deposition in the undulator walls below the acceptable limit of 1W/m, photon masks must be inserted in the undulator line. The photon mask design requires a detailed study of the power deposition in the walls and masks. This paper describes the power deposition in the undulator wall due to synchrotron radiation.Comment: Talk presented at the International Workshop on Future Linear Colliders (LCWS2018), Arlington, Texas, 22-26 October 2018. C18-10-2

Realistic undulators for intense gamma-ray beams at future colliders

The baseline designs for the ILC and CLIC require the production of an intense flux of gamma rays in their positron sources. In the case of CLIC the gamma rays are produced by a Compton backscattering source, but in this paper we concentrate on undulator-based sources as proposed for the ILC.We present the development of a simulation to generate a magnetic field map based on a Fourier analysis of any measured field map. We have used a field map measured from the ILC helical undulator prototype to calculate the typical distribution of field errors, and used them in our calculations to produce simulated field maps. We show that a loss of gamma ray intensity of ~8% could be expected, compared to the ideal case. This leads to a similar drop in positron production which can be compensated for by increasing the undulator length

Possible uses of gamma-rays at future intense positron sources

The baseline design of the ILC (International Linear Collider) positron source requires the production of an intense flux of gamma rays. In this paper we present an investigation of using the gamma ray beam of the ILC for additional applications, including nuclear physics. As a result of changing the collimator shape, as well as the parameters of the undulator magnets, we obtained spectra from numerical simulations using the HUSR/GSR software package. We present results from simulations and a discussion of possible future investigations in this paper

Translingualism in post-secondary writing and language instruction : negotiating language ideologies in policies and pedagogical practices.

Drawing on text-oriented data from the American University of Beirut, Lebanon, this study examines how writing teachers and students constantly negotiate tensions between translingual sociolinguistic realities on one hand and monolingualist assumptions about language and language relations on another that dominate curricular and pedagogical designs in first year writing courses. The study involves a multiplicity of data sources, such as official institutional documents, individual instructional materials, classroom observations, structured interviews, and a method of talk around texts. Writing teachers in this study sensitively grappled with tensions between the constant political pressures of generating the status quo and their ideological orientations towards keeping up with rapid sociolinguistic changes on the ground. As multilingual student participants in this study continued to grow more worldly with English, this study demonstrates the relevance of a translingual approach to their specific personal, social, linguistic, and cultural affiliations in addition to their academic and professional aspirations. By taking a translingual approach to writing instruction, this study puts forward strategies of ideological and pedagogical change aligned with translingualism that pays special attention to the diversity and complexity of linguistic and discursive resources already flowing into the writing program and classroom

Pragmaticalization of discourse markers in Lebanese conversational Arabic -

Thesis. M.A. American University of Beirut. Department of English, 2016. T:6438Advisor : Dr. David Wilmsen, Professor, Arabic and Near Eastern Studies ; Committee members : Dr. Kassim Shaaban, Professor, English ; Dr. Michael Vermy, Assistant Professor, English.Includes bibliographical references (leaves 73-76)The present study investigates the various uses of some of the most prevalent discourse markers in Lebanese conversational Arabic through observing their use by Lebanese participants in media discourse. I include additional examples from daily life in the discussion in order to have a comprehensive view of the roles of these discourse markers. The discourse markers involved in this study are yaʿni, ʾinnu, hallaʾ, bass, hēk, ṭayyib, and ṭab. Extracts from Lebanese talk shows are analyzed based on the functions of the discourse markers. My proposed definition for discourse markers in the present study is: Discourse markers are words that hold a pragmatic function contingent upon context, which can also derive from the word’s semantic content and-or its grammatical role. Therefore, some pragmatic functions ensue as a result of pragmaticalization. My data presents some instances where pragmatic functions of yaʿni derive from its meaning ‘it means-that is’; pragmatic functions of ʾinnu derive from its use as a complementizer; pragmatic functions of hallaʾ derive from its meaning ‘now’, pragmatic functions of bass derive from its use as a conjunction (but) or its meaning ‘only’; pragmatic functions of hēk derive from its meaning ‘this’ and ‘thus-like this’; pragmatic functions of ṭayyib derive from its meaning ‘ok’

Live Attenuated Rev-Independent Nef¯SIV Enhances Acquisition of Heterologous SIVsmE660 in Acutely Vaccinated Rhesus Macaques

Background: Rhesus macaques (RMs) inoculated with live-attenuated Rev-Independent Nef¯ simian immunodeficiency virus (Rev-Ind Nef¯SIV) as adults or neonates controlled viremia to undetectable levels and showed no signs of immunodeficiency over 6-8 years of follow-up. We tested the capacity of this live-attenuated virus to protect RMs against pathogenic, heterologous SIVsmE660 challenges. Methodology/Principal Findings Three groups of four RM were inoculated with Rev-Ind Nef¯SIV and compared. Group 1 was inoculated 8 years prior and again 15 months before low dose intrarectal challenges with SIVsmE660. Group 2 animals were inoculated with Rev-Ind Nef¯SIV at 15 months and Group 3 at 2 weeks prior to the SIVsmE660 challenges, respectively. Group 4 served as unvaccinated controls. All RMs underwent repeated weekly low-dose intrarectal challenges with SIVsmE660. Surprisingly, all RMs with acute live-attenuated virus infection (Group 3) became superinfected with the challenge virus, in contrast to the two other vaccine groups (Groups 1 and 2) (P=0.006 for each) and controls (Group 4) (P=0.022). Gene expression analysis showed significant upregulation of innate immune response-related chemokines and their receptors, most notably CCR5 in Group 3 animals during acute infection with Rev-Ind Nef¯SIV. Conclusions/Significance: We conclude that although Rev-Ind Nef¯SIV remained apathogenic, acute replication of the vaccine strain was not protective but associated with increased acquisition of heterologous mucosal SIVsmE660 challenges

The Impact of Adopting UNICEF Growth and Development Modules in Enhancing Nursing Students\u27 Knowledge: A Qualitative Study

Background: The growth and development phase are an essential and critical period of human life, especially in the early stages. It was defined by most professionals as the interval from conception to eight years of age. This interval is vital for brain growth. In addition, these developmental years have a significant and lifelong impact on children. Thus, almost all children in these years need to be well cared. Aim: The study aimed to assess the impact of adopting UNICEF modules on nursing students\u27 knowledge about growth and development concepts. Design: A qualitative study design was used to conduct the study. Participants: 40 nursing students participated in the study. Methods: Four focus nursing students’ groups were interviewed. They included two groups of the traditional curriculum, and two others for the modified curriculum according to UNICEF’s modules for growth and development. Setting: The study was conducted at the Islamic University of Gaza. Results: Most of the students in the the new curriculum mentioned that they received and learned a lot of knowledge about growth and development themes and subthemes while, unfortunately, the traditional curriculum groups did not. Conclusion: The new curriculum modified according to UNICEF modules for growth and development was effective in enhancing nursing students\u27 knowledge about growth and development conce

The Relationship Between Learner Autonomy and English Proficiency of Yemeni Postgraduate ‎English Students: A Correlational Study in Hodeidah University

Knowing the level of students' learner autonomy and its impact on their language proficiency makes teachers aware of the significance of this term for better EFL learning. Also, this helps in fostering learner autonomy especially that one of advanced students. This study investigates postgraduate students’ level of learner autonomy and its relationship with their English proficiency in a sample of 35 second-year postgraduate students undergoing two-year Master degree course in English, in the Department of English at the Faculty of Education affiliated to the University of Hodeidah, Yemen. The needed data are collected by a means of a learner autonomy questionnaire and a standard proficiency test. For data analysis, one-sample t-test and Pearson Correlation are used. The findings reveal that the learner autonomy and English proficiency of postgraduate English students, in Hodeidah University, are not ‎significantly correlated and this implies that the high or low level of English proficiency of the ‎students doesn’t imply that their learner autonomy will be high or low correspondingly.‎ Keywords: Learner autonomy, language proficiency, postgraduate (PG) ,‎ correlation and relationship

CO<inf>2</inf> absorption using diethanolamine-water solutions in a rotating spiral contactor

Results for mass transfer in a rotating spiral device are presented here for absorption of carbon dioxide from nitrogen carrier gas using mixtures of diethanolamine (DEA) and water. The ability of the device to examine the full range of flow rate ratio for the two phases while controlling the relative thicknesses of the phase layers is applied to surveying absorption performance over a wide range of DEA concentration at 312 K and 1.8 bara. Comparisons are made for a fixed 86 μm liquid layer thickness, which is shown to fix also the fraction of the liquid accessible by diffusion, while maintaining 90% removal of CO2 from a gas stream of 10% (mole) CO2 in nitrogen. The increasing liquid viscosity with DEA fraction is countered by reducing the liquid flow rate to maintain constant liquid layer thickness and diffusion depth. The allowed gas throughput, while meeting 90% removal, increases with DEA concentration until the increasing viscosity gives sufficient reduction in liquid flow rate to offset the increasing CO2 capacity of the liquid. The maximum gas flow rate has a broad peak centred at a DEA mole fraction of about 0.072 (31% by mass). Utilisation of the amine is increased as DEA concentration increases, apparently as a result of the longer residence time, suggesting an effect of chemical time scales on the order of seconds. For a fixed concentration, full utilisation of the amine is achieved by decreasing the liquid flow rate, which reduces layer thickness and increases diffusion time. The work highlights the use of the rotating spiral for rapid and accurate testing to determine optimum liquid composition of absorbent formulations

The Influence of Colour on Learning in University Libraries

This study investigated how colour can influence learning in university libraries. The main aim was to identify the impact of colour on learning performance by exploring the effect of colour on learners’ emotions and heart rate within individual study areas. Three studies were conducted to achieve the objectives. Action research was used as a methodology. To enrich the findings, this study utilises different mixed methods (qualitative and quantitative) including experiments, focus groups, questionnaire and interviews