Deployment of quality assurance procedures for digital library programmes

Many digital library programmes have a development philosophy based on use of open standards. In practice, however, projects may not have procedures in place to ensure that project deliverables make use of appropriate open standards. In addition there will be occasions when open standards are not sufficiently mature for deployment in a service environment or use of open standards will require expertise or resources which are not readily available

Quantification of Pulmonary Arterial Wall Distensibility Using Parameters Extracted from Volumetric Micro-CT Images

Stiffening, or loss of distensibility, of arterial vessel walls is among the manifestations of a number of vascular diseases including pulmonary arterial hypertension. We are attempting to quantify the mechanical properties of vessel walls of the pulmonary arterial tree using parameters derived from high-resolution volumetric x-ray CT images of rat lungs. The pulmonary arterial trees of the excised lungs are filled with a contrast agent. The lungs are imaged with arterial pressures spanning the physiological range. Vessel segment diameters are measured from the inlet to the periphery, and distensibilities calculated from diameters as a function of pressure. The method shows promise as an adjunct to other morphometric techniques such as histology and corrosion casting. It possesses the advantages of being nondestructive, characterizing the vascular structures while the lungs are imaged rapidly and in a near-physiological state, and providing the ability to associate mechanical properties with vessel location in the intact tree hierarchy

Pulmonary arterial remodeling revealed by microfocal x-ray tomography

Animal models and micro-CT imaging are useful for understanding the functional consequences of, and identifying the genes involved in, the remodeling of vascular structures that accompanies pulmonary vascular disease. Using a micro-CT scanner to image contrast-enhanced arteries in excised lungs from fawn hooded rats (a strain genetically susceptible to hypoxia induced pulmonary hypertension), we found that portions of the pulmonary arterial tree downstream from a given diameter were morphometrically indistinguishable. This \u27self-consistency\u27 property provided a means for summarizing the pulmonary arterial tree architecture and mechanical properties using a parameter vector obtained from measurements of the contiguous set of vessel segments comprising the longest (principal) pathway and its branches over a range of vascular pressures. This parameter vector was used to characterize the pulmonary vascular remodeling that occurred in rats exposed to a hypoxic (11.5% oxygen) environment and provided the input to a hemodynamic model relating structure to function. The major effect of the remodeling was a longitudinally (pulmonary artery to arterioles) uniform decrease in vessel distensibility that resulted in a 90% increase in arterial resistance. Despite the almost uniform change in vessel distensibility, over 50% of the resistance increase was attributable to vessels with unstressed diameters less than 125 microns

Micro-CT Image-Derived Metrics Quantify Arterial Wall Distensibility Reduction in a Rat Model of Pulmonary Hypertension

We developed methods to quantify arterial structural and mechanical properties in excised rat lungs and applied them to investigate the distensibility decrease accompanying chronic hypoxia-induced pulmonary hypertension. Lungs of control and hypertensive (three weeks 11% O2) animals were excised and a contrast agent introduced before micro-CT imaging with a special purpose scanner. For each lung, four 3D image data sets were obtained, each at a different intra-arterial contrast agent pressure. Vessel segment diameters and lengths were measured at all levels in the arterial tree hierarchy, and these data used to generate features sensitive to distensibility changes. Results indicate that measurements obtained from 3D micro-CT images can be used to quantify vessel biomechanical properties in this rat model of pulmonary hypertension and that distensibility is reduced by exposure to chronic hypoxia. Mechanical properties can be assessed in a localized fashion and quantified in a spatially-resolved way or as a single parameter describing the tree as a whole. Micro-CT is a nondestructive way to rapidly assess structural and mechanical properties of arteries in small animal organs maintained in a physiological state. Quantitative features measured by this method may provide valuable insights into the mechanisms causing the elevated pressures in pulmonary hypertension of differing etiologies and should become increasingly valuable tools in the study of complex phenotypes in small-animal models of important diseases such as hypertension

Chart Smart: A Need for Documentation and Billing Education Among Emergency Medicine Residents?

Objective: The healthcare chart is becoming ever more complex, serving clinicians, patients, third party payers, regulators, and even medicolegal parties. The purpose of this study was to identify our emergency medicine (EM) resident and attending physicians’ current knowledge and attitudes about billing and documentation practices. We hypothesized that resident and attending physicians would identify billing and documentation as an area in which residents need further education.Methods: We gave a 15-question Likert survey to resident and attending physicians regarding charting practices, knowledge of billing and documentation, and opinions regarding need for further education.Results: We achieved a 100% response rate, with 47% (16/34) of resident physicians disagreeing or strongly disagreeing that they have adequate training in billing and documentation, while 91% (31/34) of residents and 95% (21/22) of attending physicians identified this skill as important to a resident’s future practice. Eighty-two percent (28/34) of resident physicians and 100% of attending physicians recommended further education for residents.Conclusion: Residents in this academic EM department identified a need for further education in billing and documentation practices. [West J Emerg Med. 2010;11(2): 116-119.

Quantitative Models of the Rat Pulmonary Arterial Tree Morphometry Applied to Hypoxia-Induced Arterial Remodeling

Little is known about the constituent hemodynamic consequences of structural changes that occur in the pulmonary arteries during the onset and progression of pulmonary arterial remodeling. Many disease processes are known to be responsible for vascular remodeling that leads to pulmonary arterial hypertension, cor pulmonale, and death. Histology has been the primary tool for evaluating pulmonary remodeling, but it does not provide information on intact vascular structure or the vessel mechanical properties. This study is an extension of our previous work in which we developed an alternative imaging technique to evaluate pulmonary arterial structure. The lungs from Sprague-Dawley rats were removed, perfusion analysis was performed on the isolated lungs, and then an X-ray contrast agent was used to fill the arterial network for imaging. The lungs were scanned over a range of intravascular pressures by volumetric micro-computed tomography, and the arterial morphometry was mapped and measured in the reconstructed isotropic volumes. A quantitative assessment of hemodynamic, structural, and biomechanical differences between rats exposed for 21 days to hypoxia (10% O2) or normoxia (21.0% O2) was performed. One metric, the normalized distensibility of the arteries, is significantly (P \u3c 0.001) larger [0.025 ± 0.0011 (SE) mmHg−1] (n = 9) in normoxic rats compared with hypoxic [0.015 ± 0.00077 (SE) mmHg−1] (n = 9). The results of the study show that these models can be applied to the Sprague-Dawley rat data and, specifically, can be used to differentiate between the hypoxic and the control groups

Evidence of what works to support and sustain care at home for people with dementia: a literature review with a systematic approach

Background: This paper synthesises research evidence about the effectiveness of services intended to support and sustain people with dementia to live at home, including supporting carers. The review was commissioned to support an inspection regime and identifies the current state of scientific knowledge regarding appropriate and effective services in relation to a set of key outcomes derived from Scottish policy, inspection practice and standards. However, emphases on care at home and reduction in the use of institutional long term care are common to many international policy contexts and welfare regimes. Methods: systematic searches of relevant bibliographic databases crossing medical, psychological and social scientific literatures were followed by structured review and full-text evaluation processes, the latter using methodology-appropriate quality assessment criteria drawing on established protocols. Results: Of 131 publications evaluated, 56 were assessed to be of ‘high’ quality, 62 of ‘medium’ quality and 13 of ‘low’ quality. Evaluations identified weaknesses in many published accounts of research, including lack of methodological detail and failure to evidence conclusions. Thematic analysis revealed multiple gaps in the evidence base, including in relation to take-up and use of self-directed support by people with dementia, use of rapid response teams other multidisciplinary approaches, use of technology to support community-dwelling people with dementia, and support for people without access to unpaid or informal support. Conclusions: in many areas, policy and practice developments are proceeding on a limited evidence base. Key issues affecting substantial numbers of existing studies include: poorly designed and overly narrowly focused studies; variability and uncertainty in outcome measurement; lack of focus on the perspectives of people with dementia and supporters; and failure to understanding the complexities of living with dementia, and of the kinds of multifactorial interventions needed to provide holistic and effective support. Weaknesses in the evidence base present challenges both to practitioners looking for guidance on how best to design and deliver evidence-based services to support people living with dementia in the community and their carers and to those charged with the inspection of services

Gb/s visible light communications with colloidal quantum dot color converters

This paper reports the utilization of colloidal semiconductor quantum dots as color converters for Gb/s visible light communications. We briefly review the design and properties of colloidal quantum dots and discuss them in the context of fast color conversion of InGaN light sources, in particular in view of the effects of self-absorption. This is followed by a description of a CQD/polymer composite format of color converters. We show samples of such color-converting composite emitting at green, yellow/orange and red wavelengths, and combine these with a blueemitting microsize LED to form hybrid sources for wireless visible light communication links. In this way data rates up to 1 Gb/s over distances of a few tens of centimeters have been demonstrated. Finally, we broaden the discussion by considering the possibility for wavelength division multiplexing as well as the use of alternative colloidal semiconductor nanocrystals

Contextualizing Naturalistic Driving Data in a Rural State Among Drivers With and Without Obstructive Sleep Apnea

In naturalistic studies, Global Positioning System (GPS) data and date/time stamps can link driver exposure to specific environments (e.g., road types, speed limits, night driving, etc.), providing valuable context for analyzing critical events, such as crashes, near crashes, and breaches of accelerometer limits. In previous work, we showed how to automate this contextualization, using GPS data obtained at 1 Hz and merging this with Geographic Information Systems (GIS) databases maintained by the Iowa Department of Transportation (DOT). Here we further demonstrate our methods by analyzing data from 80 drivers with obstructive sleep apnea (OSA) and 48 controls, and comparing the two groups with respect to several factors of interest. The majority of comparisons found no difference between groups, suggesting similar patterns of exposures to driving environments in OSA and control drivers. However, OSA drivers appeared to spend slightly more time on roads with annual traffic counts of 500-10,000 and less time driving on wider highways, during twilight, and on roads with 10,000-25,000 annual traffic counts