Simlandscape: serious gaming in participatory spatial planning

In an attempt to improve support for contemporary spatial planning practice, Simlandscape has been developed. In this document the development of Simlandscape as serious game in digital form is described. In its current state, Simlandscape exists in two methodological forms; as an analogue game and as a planning support system using GIS for research and design. The game focuses on simulation of plan processes and on the resulting transformation of areas involved. Players interact with an analogue area model. The planning support system focuses on design and evaluation of plan scenarios and the data handling and presentation accompanying this process. A major challenge now is to integrate, upgrade and digitize components of the analogous game with the planning support system. Several interesting components (practical and scientific) of this project are identified and are discussed

The validity and reliability of the exposure index as a metric for estimating the radiation dose to the patient

Introduction With the introduction of digital radiography, the feedback between image quality and over-exposure has been partly lost which in some cases has led to a steady increase in dose. Over the years the introduction of exposure index (EI) has been used to resolve this phenomenon referred to as ‘dose creep’. Even though EI is often vendor specific it is always a related of the radiation exposure to the detector. Due to the nature of this relationship EI can also be used as a patient dose indicator, however this is not widely investigated in literature. Methods A total of 420 dose-area-product (DAP) and EI measurements were taken whilst varying kVp, mAs and body habitus on two different anthropomorphic phantoms (pelvis and chest). Using linear regression, the correlation between EI and DAP were examined. Additionally, two separate region of interest (ROI) placements/per phantom where examined in order to research any effect on EI. Results When dividing the data into subsets, a strong correlation between EI and DAP was shown with all R-squared values > 0.987. Comparison between the ROI placements showed a significant difference between EIs for both placements. Conclusion This research shows a clear relationship between EI and radiation dose which is dependent on a wide variety of factors such as ROI placement, body habitus. In addition, pathology and manufacturer specific EI’s are likely to be of influence as well. Implications for practice The combination of DAP and EI might be used as a patient dose indicator. However, the influencing factors as mentioned in the conclusion should be considered and examined before implementation

Measles virus-specific murine T cell clones: characterization of fine specificity function.

Measles virus (MV)-specific murine helper T cell clones (Thy-1.2+, CD4+, CD8-) were generated from mice immunized with MV-infected mouse brain homogenate by limiting dilution and in vitro stimulation of spleen cells with UV-inactivated MV Ag. The protein specificity of 7 out of 37 stable T cell clones, which displayed MHC-restricted MV Ag recognition, could be assessed by using purified MV proteins. Two fusion (F) protein-specific, two hemagglutinin-specific, and three nucleoprotein- or matrix protein-specific clones were shown to be established. The F protein-specific T cell clones together with a pane

Toward High Energy Neutrino Detection with the Radar Echo Telescope for Cosmic Rays (RET-CR)

The Radar Echo Telescope for Cosmic Rays (RET-CR) is a pathfinder experiment for the Radar Echo Telescope for Neutrinos (RET-N), a next-generation in-ice detection experiment for ultra high energy neutrinos. RET-CR will serve as the testbed for the radar echo method to probe high-energy particle cascades in nature, whereby a transmitted radio signal is reflected from the ionization left in its wake. This method, recently validated at SLAC experiment T576, shows promising preliminary sensitivity to neutrino-induced cascades above the energy range of optical detectors like IceCube. RET-CR intends to use an in-nature test beam: the dense, in-ice cascade produced when the air shower of an ultra high energy cosmic ray impacts a high-elevation ice sheet. This in-ice cascade, orders of magnitude more dense than the in-air shower that preceded it, is similar in profile and density to the expected cascade from a neutrino-induced cascade deep in the ice. RET-CR will be triggered using surface scintillator technology and will be used to develop, test, and deploy the hardware, firmware, and software needed for the eventual RET-N. We present the strategy, status, and design sensitivity of RET-CR, and discuss its application to eventual neutrino detection

The Radar Echo Telescope for Cosmic Rays

The Radar Echo Telescope for Cosmic Rays (RET-CR) was deployed in May 2023. RET-CR aims to show the in-nature viability of the radar echo method to probe in-ice particle cascades induced by ultra high energy cosmic rays and neutrinos. The RET-CR surface system detects ultra-high-energy cosmic ray air showers impinging on the ice using conventional methods. The surface detector then triggers the in-ice component of RET-CR, that is subsequently used to search for a radar echo off of the in-ice continuation of an ultra high energy cosmic ray air shower. The two systems independently reconstruct the energy, arrival direction, and impact point of the particle cascade. Here we present RET-CR, its installation in Greenland, and the first operations and results of RET-CR

Simulation and Optimisation for the Radar Echo Telescope for Cosmic Rays

The SLAC T-576 beam test experiment showed the feasibility of the radar detection technique to probe high-energy particle cascades in dense media. Corresponding particle-level simulations indicate that the radar method has very promising sensitivity to probe the > PeV cosmic neutrino flux. As such, it is crucial to demonstrate the in-situ feasibility of the radar echo method, which is the main goal of the current RET-CR experiment. Although the final goal of the Radar Echo Telescope is to detect cosmic neutrinos, we seek a proof of principle using cosmic-ray air showers penetrating the (high-altitude) Antarctic ice sheet. When an UHECR particle cascade propagates into a high-elevation ice sheet, it produces a dense in-ice cascade of charged particles which can reflect incoming radio waves. Using a surface cosmic-ray detector, the energy and direction of the UHECR can be reconstructed, and as such this constitutes a nearly ideal in-situ test beam to provide the proof of principle for the radar echo technique. RET-CR will consist of a transmitter array, receiver antennas and a surface scintillator plate array. Here we present the simulation efforts for RET-CR performed to optimise the surface array layout and triggering system, which affords an estimate of the expected event rate

Investigating signal properties of UHE particles using in-ice radar for the RET experiment

The Radar Echo Telescope (RET) experiment plans to use the radar technique to detect Ultra-High Energy (UHE) cosmic rays and neutrinos in the polar ice sheets. Whenever an UHE particle collides with an ice molecule, it produces a shower of relativistic particles, which leaves behind an ionization trail. Radio waves can be reflected off this trail and be detected in antennas. It is critical to understand such a radar signal's key properties as that will allow us to do vertex, angular and energy reconstruction of the primary UHE particle. We will discuss various simulation methods, which will fundamentally rely on ray tracing, to recreate the radar signal and test our reconstruction methods

The Radar Echo Telescope for Neutrinos (RET-N)

We present the Radar Echo Telescope for Neutrinos (RET-N). RET-N focuses on the detection of the cosmic neutrino flux above PeV energies by means of the radar detection technique. This method aims to bridge the energy gap between the diffuse neutrino flux detected by IceCube up to a few PeV and the sought for cosmogenic neutrinos at EeV energies by the in-ice Askaryan detectors, as well as the air-shower radio detectors. The radar echo method is based on the detection the ionization trail in the wake of a high-energy neutrino-induced particle cascade in ice. This technique, recently validated in a beam test (T576 at SLAC) is also the basis for the RET-N pathfinder experiment, RET-CR, which is currently under development. Based on the T-576 results, we show that the radar echo method leads to very promising sensitivities to detect cosmic neutrinos in the PeV-EeV region and above. We present the RET-N project and the results of our sensitivity studies