56 research outputs found

    The Digital Fish Library: Using MRI to Digitize, Database, and Document the Morphological Diversity of Fish

    Get PDF
    Museum fish collections possess a wealth of anatomical and morphological data that are essential for documenting and understanding biodiversity. Obtaining access to specimens for research, however, is not always practical and frequently conflicts with the need to maintain the physical integrity of specimens and the collection as a whole. Non-invasive three-dimensional (3D) digital imaging therefore serves a critical role in facilitating the digitization of these specimens for anatomical and morphological analysis as well as facilitating an efficient method for online storage and sharing of this imaging data. Here we describe the development of the Digital Fish Library (DFL, http://www.digitalfishlibrary.org), an online digital archive of high-resolution, high-contrast, magnetic resonance imaging (MRI) scans of the soft tissue anatomy of an array of fishes preserved in the Marine Vertebrate Collection of Scripps Institution of Oceanography. We have imaged and uploaded MRI data for over 300 marine and freshwater species, developed a data archival and retrieval system with a web-based image analysis and visualization tool, and integrated these into the public DFL website to disseminate data and associated metadata freely over the web. We show that MRI is a rapid and powerful method for accurately depicting the in-situ soft-tissue anatomy of preserved fishes in sufficient detail for large-scale comparative digital morphology. However these 3D volumetric data require a sophisticated computational and archival infrastructure in order to be broadly accessible to researchers and educators

    Arterial bicarbonate is associated with hypoxic burden and uncontrolled hypertension in obstructive sleep apnea - The ESADA cohort

    Get PDF
    Objective: Blood bicarbonate concentration plays an important role for obstructive sleep apnea (OSA) patients to maintain acid-base balance. We investigated the association between arterial standard bicarbonate ([HCO3-]) and nocturnal hypoxia as well as comorbid hypertension in OSA. Methods: A cross-sectional analysis of 3329 patients in the European Sleep Apnea Database (ESADA) was performed. Arterial blood gas analysis and lung function test were performed in conjunction with polysomnographic sleep studies. The 4% oxygen desaturation index (ODI), mean and minimum oxygen saturation (SpO2), and percentage of time with SpO2 below 90% (T90%) were used to reflect nocturnal hypoxic burden. Arterial hypertension was defined as a physician diagnosis of hypertension with ongoing antihypertensive medication. Hypertensive patients with SBP/DBP below or above 140/90 mmHg were classified as controlled-, uncontrolled hypertension, respectively. Results: The [HCO3-] level was normal in most patients (average 24.0 Β± 2.5 mmol/L). ODI, T90% increased whereas mean and minimum SpO2 decreased across [HCO3-] tertiles (ANOVA, p = 0.030, <0.001, <0.001, and <0.001, respectively). [HCO3-] was independently associated with ODI, mean SpO2, minimum SpO2, and T90% after adjusting for confounders (Ξ² value [95%CI]: 1.21 [0.88–1.54], βˆ’0.16 [-0.20 to βˆ’0.11], βˆ’0.51 [-0.64 to βˆ’0.37], 1.76 [1.48–2.04], respectively, all p < 0.001). 1 mmol/L elevation of [HCO3-] was associated with a 4% increased odds of uncontrolled hypertension (OR: 1.04 [1.01–1.08], p = 0.013). Conclusion: We first demonstrated an independent association between [HCO3-] and nocturnal hypoxic burden as well as uncontrolled hypertension in OSA patients. Bicarbonate levels as an adjunctive measure provide insight into the pathophysiology of hypertension in OSA

    A process for placing the human at the centre of the constructive simulation

    No full text
    This paper will describe different aspects of human behaviour and characteristics that can be represented by modelling techniques, based on ongoing work within the UK Defence Science and Technology Laboratory (Dstl), the Nederland’s Organisation for Applied Scientific Research (TNO) and the US Naval Postgraduate School (NPS). It will then propose how these characteristics can be used within a range of different types of constructive simulation, in particular agent based models. Importantly, it will also consider an integrated process of experimentation and analysis to validate and maintain development of human factors representations within constructive simulations

    Team 8: Combat Identification and Fratricide:A Human Affair

    Get PDF
    from Scythe : Proceedings and Bulletin of the International Data Farming Community, Issue 4 Workshop 16Over the past two years TNO and Dstl developed an Agent Based Combat ID Model to support the research on factors influencing the success and failure of Combat Identification processes. During the International Data farming Workshop (IDFW) 15 in Singapore, we evaluated this model by conducting the first data farming experiments. The model represents Situation Awareness (SA) and the cognitive processes to combine new sensor input with SA in order to make identification decisions. A description of the model and the results of the Singapore experiments can be found in [ref 1].Representing Urban Culture Geography in Stability Operations concerns the representation of the civilian population in a conflict environment. This working group used a scenario developed for Pythagoras and a scenario developed for a prototype multi-agent system model of the civilian population to explore the response of the civilian population to insurgent, government and stability force actions in a counterinsurgency environment. The working group also examined potential measures of merit from recent work by an irregular warfare modeling and analysis working grou
    • …
    corecore