224 research outputs found

    High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy

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    Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.Comment: Also published in JINST: http://www.iop.org/EJ/abstract/1748-0221/4/05/P0501

    The attitudes of brain cancer patients and their caregivers towards death and dying: a qualitative study

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    <p>Abstract</p> <p>Background</p> <p>Much money and energy has been spent on the study of the molecular biology of malignant brain tumours. However, little attention has been paid to the wishes of patients afflicted with these incurable tumours, and how this might influence treatment considerations.</p> <p>Methods</p> <p>We interviewed 29 individuals – 7 patients dying of a malignant brain tumor and 22 loved ones. One-on-one interviews were conducted according to a pre-designed interview guide. A combination of open-ended questions, as well as clinical scenarios was presented to participants in order to understand what is meaningful and valuable to them when determining treatment options and management approaches. The results were analyzed, coded, and interpreted using qualitative analytic techniques in order to arrive at several common overarching themes.</p> <p>Results</p> <p>Seven major themes were identified. In general, respondents were united in viewing brain cancer as unique amongst malignancies, due in large part to the premium placed on mental competence and cognitive functioning. Importantly, participants found their experiences, however difficult, led to the discovery of inner strength and resilience. Responses were usually framed within an interpersonal context, and participants were generally grateful for the opportunity to speak about their experiences. Attitudes towards religion, spirituality, and euthanasia were also probed.</p> <p>Conclusion</p> <p>Several important themes underlie the experiences of brain cancer patients and their caregivers. It is important to consider these when managing these patients and to respect not only their autonomy but also the complex interpersonal toll that a malignant diagnosis can have.</p

    Conflict transformation and history teaching: social psychological theory and its contributions

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    The aim of this introductory chapter is to render intelligible how history teaching can be enriched with knowledge of social psychological theories that deal with the issue of conflict transformation and partcularly the notions of prejudice reduction and reconciliation. A major aim of history teaching is to engage students with historical texts, establish historical significance, identify continuity and change, analyse cause and consequence, take historical perspectives and understand the ethical dimensions of historical interpretations. Such teaching, enriched with social psychological theory, will enlarge the notion of historical literacy into a study of historical culture and historical consciousness in the classroom so that students become reflective of the role of collective memory and history teaching in processes of conflict transformation and understand the ways in which various forms of historical consciousness relate the past, present and future. This is what the editors of this volume call an interdisciplinary paradigm of transformative history teachin

    Mitochondrial damage-associated molecular patterns (DAMPs) in inflammatory bowel disease

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    Background The inflammatory bowel diseases (IBD) ulcerative colitis (UC) and Crohn’s disease (CD) are chronic relapsing inflammatory disorders which have a rising incidence and cause significant morbidity. There are currently several treatment options with many more in the drug pipeline, but there are a lack of accurate biomarkers for decisions on treatment choice, assessment of disease activity and prognostication. There is a growing interest and desire for personalised or ‘precision’ medicine in IBD where novel biomarkers may help individualise IBD care in terms of diagnosis, choice of therapy, monitoring of response and detection of relapse. One class of functionally active biomarkers which have yet to be thoroughly investigated in IBD is damage-associated molecular patterns (DAMPs) including mitochondrial DNA (mtDNA). It has been recently shown that gut mitochondrial dysfunction can result in loss of epithelial barrier function and the development of colitis. Mitochondrial DAMPs have recently been described as elevated in several inflammatory diseases. Hypothesis The primary hypothesis of this thesis is that circulating levels of mtDNA is elevated in IBD. Secondary hypotheses are: (a) levels of other mitochondrial DAMPs are elevated in IBD, (b) circulating mtDNA can be used as a novel biomarker in IBD and (c) mtDNA is released locally at sites of inflammation in IBD. Methods Plasma and serum were collected prospectively from recruited IBD patients and non-IBD controls. Faeces and colonic tissue were collected from a subset of these patients. mtDNA in serum, plasma and faeces was measured using qPCR (amplifying COXIII/ND2 genes). Mass spectrometry was used to detect mitochondrial formylated peptides in the plasma of a subset of patients. IBD tissue was assessed for (a) mitochondrial damage using transmission electron microscopy (TEM) and (b) TLR9 expression, the target for mtDNA. Results 97 patients with IBD (67 UC and 30 CD), and 40 non-IBD controls were recruited. Plasma mtDNA levels were increased in UC and CD (both p<0.0001) compared to non-IBD controls; with significant correlations with blood (CRP, albumin, white cell count), clinical and endoscopic markers of severity; and disease activity. In active UC, we detected significantly higher circulating mitochondrial formylated peptides and faecal mtDNA levels (vs. non-IBD controls [p<0.01 and <0.0001 respectively]) with demonstrable TEM evidence of intestinal mucosal mitochondrial damage. In active IBD, TLR9+ lamina propria inflammatory cells were significantly higher in UC/CD compared to controls (both p<0.05). Conclusions Taken together, the findings suggest mtDNA is released during active inflammation in inflammatory bowel disease and is a potential novel mechanistic biomarker
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