TRImP - A new facility to produce and trap radioactive isotopes

At the Kernfysisch Vensneller Institiutr (KVI) in Groningen, NL, a new facility (TRImP) is under development. It aims for producing, slowing down, and trapping of radioactive isotopes in order to perform accurate measurements on fundamental symmetries and interactions. A production target station and a dual magnetic separator installed and commissioned. We will slow down the isotopes of interest using an ion catcher and in a further stage a radiofrequency quadropole gas cooler (RFQ). The isotopes will finally be trapped in an atomic trap for precision studies.Comment: Proceedings of the XXIX Mazurian Lakes Conference on Physics (Sep. 2005, Piaski, Poland

Detection of brain stroke in simulation and realistic 3-D human head phantom using microwave imaging

Brain stroke is globally one of the most widespread sorts of brain abnormalities. There are common symptoms between the transient ischemic attack (TIA), strokes and generic medical conditions like fainting, migraine, heart problems and seizures. Therefore, the other health conditions should not be misdiagnosed with stroke. It is well known that providing immediate medical attention for a patient with a brain injury is of vital importance. Every second, from the moment of brain injury, millions of brain cells die, leading to irreparable and permanent damage or even death. Thus, if medical staff diagnose stroke, and perform an appropriate drug treatment within a few hours of the symptoms onset, they play a crucial role in saving a patient’s life. The key factor in treatment is to reliably diagnose the stroke immediately. Hence, a portable diagnosic system is pivotal on the spot for rapid diagnosis of brain injuries. Initially, a clinical examination using a neurological assessment is performed by a general practitioner (GP). Compared to CT and MRI scanners, microwave imaging (MWI) can provide a portable detection system, and allow initial diagnosis of various emergency, life-threatening circumstances such as strokes due to brain injury, whilst patients are still being taken by ambulance to hospital, and saving critical time. In recent years, MWI has emerged as a promising non-ionising and non-invasive technology for a range of applications, particularly medical applications. In the current thesis, radar-based MWI is proposed as a procedure for brain haemorrhagic stroke detection. This imaging procedure has also more advantages such as low cost, being portable, fast, and easy to use with a good potential for brain haemorrhage detection. In MWI, the imaging of different human head tissues relies on their different response (i.e., electric contrast) to an applied microwave radiation. MWI is a screening technology for detection and monitoring of haemorrhagic stroke, tumours and cancerous cells, based on the significant contrast in the dielectric properties at microwave frequencies of normal and abnormal tissues. This thesis deals with the use and validation of an innovative low complexity MWI procedure for brain imaging, where antennas operate in free space. In particular, we employ only two microstrip antennas, operating between 1 and 2 GHz for successful detection of the haemorrhagic stroke. Detection is achieved using both simulation and experimental measurements. I. In the first stage, a wideband (WB) microstrip antenna with fractal ground plane is proposed, simulated and fabricated for brain haemorrhage detection. The designed antennas exhibit a WB working frequency between 1-2 GHz. This band has demonstrated to be ideal and optimal to do brain imaging; in addition, it is obviously emphasised that WB can enhance performance in lesion detection. The simulations have been performed applying an anthropomorphic human head model where a haemorrhagic stroke has been inserted (using CST Microwave studio). The simulation results concluded that the emulated brain haemorrhagic stroke can be distinguished at four different positions of 0◦, 5◦, 40◦, and 45◦. II. The second stage of this study presents a hemi-ellipsoidal human head phantom with a millimetric cylindrically-shaped inclusion to emulate brain haemorrhage (suitable to be used inside the anechoic chamber) and a human head phantom (suitable to be applied in MWI device). The process has been performed based on the following procedures: - In the second, stage, first, multi-biostatic frequency-domain measurements have been performed to collect the transfer function (S21) between two proposed mono-static radar system based antennas inside an anechoic chamber using a multi-layered phantom mimicking a human head. This procedure is used to measure the received signal (S21). A Vector Network Analyser (VNA) is linked to the mentioned antennas, and the measured (S21) are recorded when they changed the position to every new observation position. Subsequently, the measured (S21) are post-processed in order to generate microwave images with emphasising the object (e.g. the tumour or the stroke). In this stage, on the basis of the measurement results, it is concluded that the object (brain haemorrhagic stroke phantom) can be successfully detected at four different positions of 0◦, 90◦, 180◦ and 270◦. - Secondly, since the results coming from measurements inside the anechoic chamber are not as realistic as clinical trials reports and also there is a medical requirement for a brain stroke portable imaging device, we have come to a decision on applying different signal pre-processing methods to the imaging results collected from a portable MWI device for brain haemorrhage imaging. A portable MWI device, which operates in free space with two azimuthally-rotating antennas, has been used for brain haemorrhage detection. Measurements are performed by recording the complex (S21) in a multi-bistatic fashion, i.e. for each transmitting position the receiving antenna is moved to measure the received signal every 4.5◦, leading to a total of 80 receiving points. In conclusion, based on the results of the MWI device, the inclusion emulating the brain haemorrhage may be detected at four different positions of 0◦, 90◦, 180◦ and 270◦. In this thesis, all images have been obtained through Huygens Principle (HP). To reconstruct the image, signal pre-processing techniques are used to reduce artefacts (which may be due to the direct fields and the fields reflected by the first layer). Subtraction artefact removal method between the data of a healthy head and the data of a head with stroke has been initially employed in simulation and measurements. Accordingly, an "Ideal" image would be generated using this artefact removal method to prove the concept of the technology. This would mean that the "Ideal" image performed as a reference for the comparison with the resulting image from using other artefact removal methods. It is important to point out that, for the purposes of real scenario, there is no possibility of applying this artefact removal method to medical imaging, where the ideal response is not calculated or known. Hence, in clinical trials this artefact removal method cannot be helpful. In addition to the subtraction artefact removal method, in this research, four more methods have been introduced and investigated. These methods consist of rotation subtraction, average subtraction, differential symmetric receiver type, and summed symmetric differential. The subtraction and rotation subtraction artefact removal methods have been used both in simulations and measurements. It has been verified that all artefact removal procedures allow detection. Subsequently, 6 dedicated image quantification procedures have been implemented in order to assess the detection capability. These procedures comprise area difference, centroid difference, signal-to-noise ratio, structural similarity index metric, image quality index, and signal-to-clutter ratio. Validation of the techniques through both simulation and experimental measurements have been performed and presented, illustrating the effectiveness of the methods

Essays on Tax Efficiency

This dissertation addresses questions on tax and efficiency. In particular, the main research question in essay one is: what is the impact of state and local taxes as well as expenditure policies on the level, growth, and ratio of high wage workers in U.S. In particular, this essay tries to identify whether interstate differences in state-local level fiscal policies are the main driving force to attract high wage workers or not. Based on Roback (1982) and Epple-Plat’s (1998) model, a theoretical model in presented in which the relationship appears as ambiguous. Empirically, current population survey (CPS) data is used to find out the impact of tax policies. In CPS data, I define high wage workers as one who has earnings greater than 75 percentile of U.S wage distribution. Additionally, Occupational Employment Statistics (published by Bureau of Labor Statistics) is used in which I characterize high wage workers as one who has wages greater than 75 percentiles of all workers in each occupation in the U.S. I include total number of high wage workers, growth of high wage workers, and ratio of high wage to total number of workers in the analysis and examine how fiscal policies affect different forms of high wage workers. The results show that state –local taxes are not the major factors to attract high wage workers although expenditure policies have a positive impact in some cases. I also check the validity of the results by incorporating different time periods, sets of high wage growing states, and various other ways in order to define high wage workers. All the results are consistent with the main findings. Essay two analyzes the impact of enforcement on tax evasion in U.S. Due to declining budget for enforcement in U.S, the tendency to evade taxes has gone up over the years. Recent data from Internal Revenue Service (IRS) reveals that tax evasion costs the Federal Government $458 billion between 2008 through 2010. This suggests that strong enforcement policies, as well as a rise, in the budget for enforcement are needed in U.S. I use original Allingham-Sandmo (1972) model in which they found a positive relationship between audit or enforcement and tax compliance. Using Individual Tax Model Data File for 2008 and annual state level data from 1980 to 2014, this paper finds that enforcement has a significant impact on tax compliance. There is a possibility that individuals may respond differently at various levels of income. Here I provide evidence that individual’s responses vary at different stages of income. Furthermore, state level annual data indicates that higher level of enforcement expenditure does decrease the likelihood to avoid taxes. Essay three uses the same theoretical model to examine the impact of sales tax evasion on macroeconomic indicators for a developing country Pakistan. The performance of Pakistan in terms of tax collection is very poor and the government is trying to minimize the loss from tax evasion by incorporating a VAT type general sales tax. Using a computable general equilibrium model, this essay explores the link between sales tax rate, tax gap in sales tax and enforcement level, evasion, and observe the consequences of the evasion on macroeconomic factors. In particular, we run two simulations in which the base case incorporates sales tax evasion of 25 percent and the modified case includes full compliance of the general sales tax. The outcome indicates an increase in Real GNP growth rate, Tax-GDP ratio, and a reduction in the budget deficit

The intellectual, ethical, and, spiritual dimensions of the Islamic thought

The intellectual inquiry and acquisition of knowledge have always been integral to Islam, right from the first revelation recorded by the Qur’an. This paper aims to examine how the origin, role, and purpose of intellect have been understood in Islamic thought from its inception and through its subsequent evolution. It further aims to discuss the role and purpose that intellect and ethics ought to serve in the faith and lives of contemporary Muslims. Muslim philosophers based their ideas on teachings of the Qur’an and teachings of Prophet Muhammad. They utilized their intellect to share this significant knowledge with their contemporary intellectuals to further human reasoning and inquiry at large. In Islamic thought, Intellect and ethics go hand in hand. A crucial objective here is to determine the essential meaning of Jihad, so as to establish a sound intellectual basis for ethical behavior. Understanding the role that intellect can and should play in a Muslim’s life holds the key to resolving crucial problems that contemporary Muslims face, such as the rise of various forms of fundamentalism and misconceptions of Jihad. I hope to show that Islamic ethics and spirituality grounded in conscientious intellectual inquiry can be instrumental in counteracting and overcoming ignorance and unwarranted violence

When Sita met Belle: an Indian woman finds her voice through re-visioning fairy tales.

Masters Degree. University of KwaZulu-Natal, Pietermaritzburg.The dissertation comprises a creative component and a reflection paper. The creative component is a novella titled “When Sita Met Belle.” The novella engages with the Beauty and the Beast narrative written from an Indian woman’s perspective and set in a South African context. It draws upon the experiences of Sita from Tulsidasa’s Sri Ramacharitamanasa and Belle from Suzanne Barbot de Villeneuve’s La Belle et la Bête, or Beauty and the Beast. Belle and Sita are alike in their voiceless qualities and experiences, which reverberate through the female characters in “When Sita Met Belle.” Each chapter is based on a different strand of the Beauty and the Beast narrative. The epigraphs from the Sri Ramacharitamanas create the overarching mood of Sita’s experiences in the creative component and connect with the Indian context of the piece. The reflection paper discusses the re-visioning of the Beauty and the Beast fairy tale from a modern feminist point of view incorporating elements from Sri Ramacharitamanasa. It explores the re-visioning of a fairy tale from a feminist angle, outlining previous re-visions of the Beauty and the Beast fairy tale, the contributions by Margaret Atwood and Angela Carter as writers who have influenced this re-vision, the contextualisation of the Beauty and the Beast narrative, the depiction of Sita and Belle in their relative stories, and the Disney treatment of fairy tales. Thereafter there is an explanation of my choices of re-visioning in the novella and a summary of the necessity of re-visioning fairy tales. The reflection paper comments on encouraging female agency lacking in the protagonists of Belle and Sita, and reveals how this is achieved through a re-vision. Of the two genders, only one can truly encapsulate and convey the female experience in a creative and positive expression. As both the fairy tale of Beauty and the Beast and the Hindu text of Sri Ramacharitamanasa are adaptable to the times, they offer the possibility of a re-vision which makes heroes of heroines

Recruitment of the ribosomal 40S subunit to the 3\u27untranslated region of a viral mRNA, via the eIF4 complex, facilitates cap-independent translation

Translation of uncapped plant viral RNAs can be facilitated by either an internal ribosomal entry site (IRES) in the 5\u27 untranslated region (UTR) or a cap-independent translation element (CITE) in the 3\u27 UTR. Barley yellow dwarf virus (BYDV) mRNA, which lacks both cap and poly(A) tail, has a translation element (3\u27BTE) in its 3\u27 UTR that is essential for efficient translation initiation at the 5\u27-proximal AUG. This mechanism requires binding of the eukaryotic initiation factor 4G (eIF4G) subunit of the heterodimer eIF4F to the 3\u27BTE and base pairing between the 3\u27BTE and the 5\u27 UTR. Here we investigate how this interaction recruits the ribosome to the 5\u27 end of the mRNA. Using fluorescence anisotropy, SHAPE analysis and toe printing, we found that (i) 40S ribosomal subunits bind to the 3\u27BTE, (ii) the helicase complex eIF4F-eIF4A-eIF4B-ATP increases affinity of 40S subunit binding to the conserved SL-I of the 3\u27 BTE by exposing more unpaired bases of the 3\u27BTE and (iii) long-distance base pairing transfers this complex to the 5\u27 end of the mRNA where translation initiates. These results reveal an utterly novel mechanism of ribosome recruitment to an mRNA