Investigation and optimisation of a plasma cathode electron beam gun for material processing applications

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University London.This thesis describes design, development and testing work on a plasma cathode electron beam gun as well as plasma diagnosis experiments and Electron Beam (EB) current measurements carried out with the aim of maximising the power of the EB extracted and optimising the electron beam gun system for material processing applications. The elements which influence EB gun design are described and put into practice in a thermionic EB gun case study. The relevant principles of plasma EB gun systems, such low-temperature, low-pressure, RF excitation, are described along with the test rigs developed to investigate different plasma cathode configurations. The first experimental setup was for optical spectroscopy measurements of the light emitted from the plasma and the second included current measurements from EBs generated at –30 and –60 kV as well as the spectroscopic measurements. Comparison of EB current measurements with different plasma cathode configurations and correlation with spectroscopic measurements are presented. The maximum current extracted from the Radiofrequency (RF) gun was 38 mA at –60 kV using a hollow cathode geometry and permanent magnets for electron confinement. The RF gun was compared to a Direct Current (DC) gun which generated higher currents. This was reflected in the spectra which indicated a higher ionisation level than in the RF plasma. Simulation work carried out using Opera-2d to model beam trajectories indicated that the beam shape is largely influenced by the plasma boundary. Particle In Cell (PIC) simulations of a parallel plate RF plasma cathode demonstrated that higher excitation frequencies produced higher ionisation, however the RF sheaths were larger and thus the current extracted may be limited in practice due to fewer electrons being available near the aperture. The sheath thickness decreased in the simulations as the discharge gap was increased. RF plasma also produced larger currents from larger plasma chambers.TWI Ltd

The Impact of the International Convention on the Rights of Persons with Disabilities on Qatari Domestic Legislation

The entry into force of the International Convention on the Rights of Persons with Disabilities means that State Parties shall adapt their legislation and regulation to the social model designed in the international text. The present work aims to identify the general challenges faced by Qatar in that task. After presenting the keys to understanding the requirements of the Convention, the paper underlines the necessity of a cultural change in addition to a legal one. In this way, Qatar shares with other State Parties theoretical, legal, social and economic problems. Specifically, the current medical model in Qatar policies should be replaced with the conventional social model. This implies the elimination of discrimination based on disability, the universal accessibility, the legal capacity for persons with disabilities and their right to live independently. A priority is to generate an associative movement around disability

Interdependence, indivisibility and the social rights of persons with disabilities in the law of Qatar

Based on the description of the situation of some social rights of persons with disability in Qatar, this article is aimed to highlight the need to address the protection of human rights from interdependence and indivisibility. The analysis of Qatar Law reveals that social protection alone is not sufficient guarantee of dignity, as would not be a system based exclusively on freedom as not interference. Although providing noteworthy resources for persons with disabilities along with a good level of social protection and health care, Qatar does not base its system on autonomy and inclusion and this is a shortcoming to move towards a human rights-based approach

La despenalización del homicidio piadoso para lograr la incorporación de la eutanasia a través de un protocolo médico

La presente investigación tuvo como objetivo Despenalizar el Homicidio Piadoso para lograr la incorporación de la Eutanasia a nuestro Ordenamiento Jurídico a través de la proposición de un protocolo médico que sea aplicable para personas con enfermedades terminales teniendo como base una serie de derechos y legislaciones que son de suma importancia para el desarrollo del presente. La presente investigación presenta un enfoque cualitativo, está derivada de una investigación de tipo básico. A su vez, la presente Investigación pertenece a la Teoría Fundamentada. Los participantes del presente informe de investigación fueron abogados en materia constitucional, fiscales penales y médicos encargados del área de pacientes con enfermedades terminales del Hospital de la ciudad de Huaraz, la técnica empleada fue la entrevista a profundidad y nuestro instrumento de recolección de datos fue la ficha de entrevista a profundidad, que nos permitió examinar y determinar los aportes que brinda el presente informe de investigación. Después del análisis interpretativo se llegó a la conclusión que con la Despenalización del Homicidio Piadoso se lograría implementar la eutanasia, siempre que el solicitante padezca una enfermedad terminal que haga imposible el desarrollo de su vida de manera digna

The GeV to TeV view of SNR IC443: predictions for Fermi

We present a theoretical model that explains the high energy phenomenology of the neighborhood of SNR IC 443, as observed with the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescope and the Energetic Gamma-Ray Experiment Telescope (EGRET). We also discuss how the model can be tested with observations by the Fermi Gamma-ray Large Area Space Telescope. We interpret MAGIC J0616+225 as delayed TeV emission of cosmic-rays diffusing from IC 443 and interacting with a known cloud located at a distance of about 20 pc in the foreground of the remnant. This scenario naturally explains the displacement between EGRET and MAGIC sources, their fluxes, and their spectra. Finally, we predict how this context can be observed by Fermi.Comment: To appear in the Proceedings of the 6th Workshop on Science with the New Generation of High Energy Gamma-Ray Experiments (SciNeGHE '08), held in Padova October 200

Editorial:Plant Phenotyping and Phenomics for Plant Breeding

publishersversionPeer reviewe

Qatar before the Committee on the Rights of Persons with Disabilities

Background: The Convention on the Rights of Persons with Disabilities (the CRPD) is the first human rights treaty of the 21st century and the first binding instrument specifically focused on protecting persons with disabilities within the framework of the UN's universal system of human rights. The CRPD came into force on May 3, 2008, and as of December 3, 2016 it has been ratified by 168 states. The CRPD developed the Committee on the Rights of Persons with Disabilities (Article 34) to monitor compliance with the Convention by States Parties. The main role of the Committee is to review the reports (both the initial and the periodic reports) submitted by States Parties pursuant to Article 35 of the CRPD. In accordance with the CRPD Article 35, States Parties are required to submit to the Committee “a comprehensive report on measures taken to give effect to its obligations [under the CRPD] … and on the progress made in that regard” within two years after the entry into force of the present Convention for the State Party concerned, and subsequently they must submit periodic reports every four years “and further whenever the Committee so requests.” Qatar ratified the UNCRPD in May 2008 and is obliged as a signatory nation to implement a number of social and legal measures to become fully compliant. Aim: The aim of this paper is to identify Qatar»s degree of compliance with the CRPD as per the last available CRPD reports. Subsequently, we list recommended actions toward Qatar's compliance with the Convention. Findings and recommendations: On June 19, 2012 Qatar submitted its report to the Committee on its compliance with the Convention. Following review of the Qatar report, the committee made six concluding observations. The six observations made by the Committee on the Rights of Persons with Disabilities on Qatar's compliance with the Convention: The legislation revolves around a medical (treatment) model of disability, in contrast to the convention's call for a social model and the human rights approach. It is necessary to safeguard non-discrimination, adopting the inclusive social model. Accommodation and accessibility are not in line with the Convention. There is an absence of specific legal and policy frameworks to ensure accessibility for persons with disabilities on an equal basis with others, and reasonable accommodation is not sufficiently guaranteed. Lack of consultation and participation of persons with disabilities in the drafting of regulatory policies that affect them. Lack of systematic information. There is no independent internal mechanism to coordinate policy on the rights of persons with disabilities and monitor the implementation of the Convention. The Committee's six concluding observations on the rights of persons with disabilities indicate that Qatar, similar to many other countries, has a long way to go before reaching compliance with the convention. As a first step towards compliance with the Convention, Qatar action regarding the six issues highlighted here is key, and can be as follows: Adopt a social model whereby the state moves beyond the assistance-based approach to the development of actual individual rights enforceable in a court of law, considers disability rights as validity standards, and regards the field of conflict of rights as other rights or fundamental legal interests. Prevent discrimination by adopting an inclusive social model, as well as via adapting both the situation strategy (equality focused on the situation) and the identity strategy (acknowledging the rights of specific persons or groups). Provide accessibility through universal design and reasonable accommodation. Consult and include persons with disabilities in the drafting of regulatory policies that affect them. Collect systematic (research and statistical) data on persons with disability for use in the development and implementation of policies. Put in place an independent internal mechanism to coordinate policy on the rights of persons with disabilities and monitor the implementation of the Convention. Acknowledgement: This presentation was made possible by the support of the NPRP grant 7 - 380 - 5 - 051 from the Qatar National Research Fund. The statements made herein are solely the responsibility of the authors.Qscienc

Frailty is associated with objectively assessed sedentary behaviour patterns in older adults: Evidence from the Toledo Study for Healthy Aging (TSHA)

Objective: The aim of this study was to examine the association of sedentary behaviour patterns with frailty in older people. Setting: Clinical setting. Design: Cross-sectional, observational study. Participants and measurements: A triaxial accelerometer was used in a subsample from the Toledo Study for Healthy Aging (519 participants, 67–97 years) to assess several sedentary behaviour patterns including sedentary time per day, the number and duration (min) of breaks in sedentary time per day, and the proportion of the day spent in sedentary bouts of 10 minutes or more. Frailty was assessed using the Frailty Trait Scale (FTS). Regression analysis was used to ascertain the associations between sedentary behaviour patterns and frailty. Results: Sedentary time per day and the proportion of the day spent in sedentary bouts of 10 minutes or more, were positively associated with frailty in the study sample. Conversely, the time spent in breaks in sedentary time was negatively associated with frailty. Conclusion: In summary, breaking up sedentary time and time spent in sedentary behaviour are associated with frailty in older people