Sustainability of a university designed and developed media annotation tool to prepare learners with skills needed for future employment

RMIT University‘s media annotation tool (MAT) is a computer software program dedicated to incorporating video footage to the student learning experience in a novel manner. In addition to the usual functions associated with videos, MAT allows users to enter written comments at strategic and key positions to emphasise the required learning points. Innovatively introduced to creatively support learning for work-ready skills, in 2011 MAT was integrated into courses across nine student cohorts, over six disciplines, in the Vocational and Higher Education (undergraduate and post graduate) sectors of the university. This paper will focus on analysis of insights of teacher experiences using MAT, highlighting sustainable ways forward with university designed innovations. It will introduce the context of implementing MAT and discuss the process of evaluating the requirements for promoting MAT to the wider university community and, more specifically, to embed and sustain MAT into the long-term

Lymph node imaging with magnetic resonance, positron emission tomography and fluorescence techniques

The knowledge that unbound gadolinium was responsible for NSF highlighted the need for alternative and safer imaging agents for MRI applications. Nanoparticles (used in conjunction with MRI) were identified as offering the potential and promise, to be safer across a multitude of applications; some dedicated for the investigation of specific disease processes. In particular, iron oxide nanoparticles have been considered as offering the greatest possibility as an MRI contrast (imaging) agent in both the research and clinical arenas. Advantages offered by T10 dextran coated iron oxide nanoparticles include human biocompatibility with a safe and known excretion pathway. The dextran coating can be functionalised, thus providing opportunities for creative compounds to be created. For example, experimental work contributing to this thesis has resulted in T10 dextran coated iron oxide nanoparticles being radiolabelled with 68Ga – and this is being presented for consideration as a potential imaging agent for PET/MRI; that is, 68Ga providing an imaging agent effect on PET imaging while the iron oxide component provides simultaneous imaging contrast with MRI. 68Ga itself provides an advantage over 99mTc (the most commonly used PET imaging agent); it has an improved imaging sensitivity over 99mTc and is less costly to generate, requiring 68Ge (a radio-isotope of germainium) and a gallium generator. The clinical benefit to developing iron oxide nanoparticles radio-labelled with 68Ga is also to improve the imaging of lymph nodes in oncology patients (as well as a PET/MRI contrast agent). Also presented here are the PET imaging findings, identifying the prostate draining lymph nodes, from four prostate cancer patients having had these nanoparticle preparations directly injected into their prostate glands. Iron oxide nanoparticles can also be loaded into immune cells, in vitro; for this thesis, murine dendritic cells (bone marrow derived) and human dendritic cells (monocyte derived) were used, as dendritic cells are known to migrate to lymph nodes. The combination of iron oxide nanoparticles radiolabelled with 68Ga, and in vitro cell loading, offer the potential to re-visit cellular MRI to determine if imaging advances can be made in this area. To support these achievements and claims, this thesis includes in vitro murine dendritic cell and in vitro human dendritic cell studies and also in vivo murine and in vivo human imaging studies. Chapter 1 provides a review of the literature, identifying; the advantages of iron oxide nanoparticles over the limitations of gadolinium based contrast agents; their relevance to MRI and also their capabilities of being internalised by certain cells for targeting imaging applications. The overall aims of the thesis are presented. Chapter 2 explains in detail the materials used, the methods employed and the physical and chemical processes that underpin all of the in vitro and in vivo experiments. The processes used draw upon knowledge from a range of disciplines, including cell biology, immunology, chemistry, physics, medical imaging, nuclear medicine and radiopharmaceuticals. This chapter describes how the iron oxide nanoparticles were prepared and the radiolabelling process used. The functionalised method used for the T10 dextran coating is explained, thus providing attachment sites for either 68Ga or fluorescent markers such as FITC or R-PE for in vitro (murine and human) and in vivo (murine) experiments. Also described are the in vitro cellular (murine and human) experimental process with dendritic cells and iron oxide nanoparticles, investigating dose dependent and time dependent uptake. Chapter 3 provides an analysis of the physical characteristics of the laboratory produced T10 dextran coated iron oxide nanoparticles (using TEM and SEM) and an important assessment of how these nanoparticles behaved in a magnetic environment, namely at 1.5T and 3.0T clinical MRI environment; calculating and graphing the R2 and T2 relaxivity rate values of nanoparticle concentration at a specific TE value and magnetic field strength. The methodology of radiolabelling these nanoparticles with 68Ga is described and the results of TLC are provided, demonstrating the levels of bound and unbound 68Ga. Any effects T10 dextran coated iron oxide nanoparticles could cause on cell proliferation was assessed with PBMC using the MTS assay technique and compared with the effect that Dotarem® (safest gadolinium based contrast agent) may have on these same cells. Chapter 4 investigates the characterisation of nanoparticle uptake by murine bone marrow derived dendritic cells (GM-CSF and Flt3) in vitro, with dose (concentration) dependent and time dependent uptake studies. These same BM-DCs were observed for apoptotic effects, in vitro, using various nanoparticle concentrations over a 24 hour incubation period. A murine CBA kit was used to also ascertain any inflammatory response in these BM-DCs to the presence of nanoparticles; assessed using the supernatant from in vitro experiments Chapter 5 reports on the characterisation of nanoparticle uptake by human monocyte derived DCs, in vitro. Dose (concentration) dependent and time dependent uptake in CD14+ and CD11+ cells were identified. In vitro supernatant assessment for an inflammatory response using a human CBA kit was used. Dose dependent uptake, in vitro, was also quantified in other cells that play varying roles in an immune response; namely PBMC, lymphocytes, granulocytes/monocytes. Chapter 6 examines in vivo applications of nanoparticle preparations; murine and human. Lymphatic drainage to the popliteal and inguinal lymph nodes in C57/BL6 female mice were assessed using flow cytometry; following local subcutaneous injection of T10 dextran coated iron oxide nanoparticles tagged with FITC. To observe any systemic effects of these nanoparticles in these mice, biochemical analysis of blood serum was conducted and histopathological assessment performed, using H&E and Perls Prussian Blue, of the heart, lungs, liver, spleen and kidneys and PAS staining of the kidneys (to observe the basement membrane). Following footpad injections of T10 dextran coated IONPs tagged with FITC and radiolabelled with 68Ga, separate PET and MRI imaging of mice was conducted and on both imaging modalities, image contrast effects due to 68Ga (PET) and iron oxide nanoparticles (MRI) were identified. Most importantly, PET imaging results from patients (positive for prostate cancer) undergoing insertion of gold seeds (for later radiotherapy treatment) having T10 dextran coated IONPs radiolabelled with 68Ga demonstrated observed drainage to lymph nodes with the PET component of a PET/CT scanner

The sonographer’s role in RFA therapy of liver lesions

Interventional techniques using ultrasound guidance, such as Radio Frequency Ablation (RFA) of liver lesions, are the domain of the radiologist. However, real time ultrasound imaging as performed by the sonographer, is critical in monitoring the successful insertion and placement of the RFA needle. RFA is used to create a localised and controlled application of heat in order to induce necrosis of cells within the liver lesions

Results from the first use of low radioactivity argon in a dark matter search

Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar-39 at a level reduced by a factor (1.4 +- 0.2) x 10^3 relative to atmospheric argon. We report a background-free null result from (2616 +- 43) kg d of data, accumulated over 70.9 live-days. When combined with our previous search using an atmospheric argon, the 90 % C.L. upper limit on the WIMP-nucleon spin-independent cross section based on zero events found in the WIMP search regions, is 2.0 x 10^-44 cm^2 (8.6 x 10^-44 cm^2, 8.0 x 10^-43 cm^2) for a WIMP mass of 100 GeV/c^2 (1 TeV/c^2 , 10 TeV/c^2).Comment: Accepted by Phys. Rev.

The diagnostic MRCP examination: overcoming technical challenges to ensure clinical success

The magnetic resonance cholangiopancreatography (MRCP) examination has all but replaced the diagnostic endoscopic retrograde cholangiopancreatography (ERCP) examination for imaging the biliary tree and pancreatic ducts in many practical aspects of the clinical setting. Despite this increase in popularity, many magnetic resonance imaging (MRI) radiographers still find aspects of the MRCP examination quite challenging. The aim of this tutorial paper is to provide useful technical advice on how to overcome such perceived challenges and thus produce a successful diagnostic MRCP examination. This paper will be of interest to novice MRI radiographers who are at the beginning of their learning curve in MRCP examination. Other MRI radiographers who are interested in practical tips for protocol variations may also find the paper useful

Development and use of iron oxide nanoparticles (Part 1): Synthesis of iron oxide nanoparticles for MRI

Contrast agents, such as iron oxide, enhance MR images by altering the relaxation times of tissues in which the agent is present. They can also be used to label targeted molecular imaging probes. Unfortunately, no molecular imaging probe is currently available on the clinical MRI market. A promising platform for MRI contrast agent development is nanotechnology, where superparamagnetic iron oxide nanoparticles (SPIONS) are tailored for MR contrast enhancement, and/or for molecular imaging. SPIONs can be produced using a range of methods and the choice of method will be influenced by the characteristics most important for a particular application. In addition, the ability to attach molecular markers to SPIONS heralds their application in molecular imaging

DarkSide-50 532-day dark matter search with low-radioactivity argon

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOThe DarkSide-50 direct-detection dark matter experiment is a dual-phase argon time projection chamber operating at Laboratori Nazionali del Gran Sasso. This paper reports on the blind analysis of a (16 660 +/- 270) kg d exposure using a target of low-radioactivity argon extracted from underground sources. We find no events in the dark matter selection box and set a 90% C. L. upper limit on the dark matter-nucleon spin-independent cross section of 1.14 x 10(-44) cm(2) (3.78 x 10(-44) cm(2), 3.43 x 10(-43) cm(2)) for a WIMP mass of 100 GeV/c(2) (1 TeV/c(2), 10 TeV/c(2)).9810117FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO2016/09084-0Agências de fomento estrangeiras apoiaram essa pesquisa, mais informações acesse artig

Constraints on sub-GeV dark-matter-electron scattering from the DarkSide-50 experiment

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOWe present new constraints on sub-GeV dark-matter particles scattering off electrons based on 6780.0 kg d of data collected with the DarkSide-50 dual-phase argon time projection chamber. This analysis uses electroluminescence signals due to ionized electrons extracted from the liquid argon target. The detector has a very high trigger probability for these signals, allowing for an analysis threshold of three extracted electrons, or approximately 0.05 keVee. We calculate the expected recoil spectra for dark matterelectron scattering in argon and, under the assumption of momentum-independent scattering, improve upon existing limits from XENON10 for dark-matter particles with masses between 30 and 100 MeV/c(2).1211117FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO2016/09084-0Agências de fomento estrangeiras apoiaram essa pesquisa, mais informações acesse artig

DarkSide status and prospects

Sem informaçãoDarkSide uses a dual-phase Liquid Argon Time Projection Chamber to search for WIMP dark matter. The current detector, DarkSide-50, is running since mid 2015 with a target of 50 kg of Argon from an underground source. Here it is presented the latest results of searches of WIMP-nucleus interactions, with WIMP masses in the GeV-TeV range, and of WIMP-electron interactions, in the sub-GeV mass range. The future of DarkSide with a new generation experiment, involving a global collaboration from all the current Argon based experiments, is presented.422-315Sem informaçãoSem informaçãoSem informaçã