![]() ![]() News and World Report, February 16, 1998, "Whoops, there goes another CD-ROM" ). (See, for example, Business Week, "From Digits to Dust," April 20, 1998, p. Who among us can read our old WordStar or VisiCalc files? Find our first email message? Or, on a larger scale, what happens to the history of science if we can't read the first data from the first interplanetary exploration by the Viking mission to Mars? The origins of the digital era are probably already lost, and millions must be spent if strategic government and corporate records are to survive the transition to the year 2000 on digital clocks. This paper, then, is the product of a dialogue between a computer scientist/entrepreneur and a political theorist/librarian, and represents an attempt to create a common agenda for action. Our purpose is not so much to answer these questions in a definitive manner, but to organize a discussion between communities which must learn to work together if the problem of digital preservation and archiving is to be solved - computer scientists, librarians and scholars, and policy makers. What will be the consequences of these changes in the nature of the medium for creating and preserving our cultural heritage? What new technological and institutional strategies must be invented to archive cultural artifacts and hand them on to future generations? We will explore these questions through the practical perspective gained in building Alexa Internet and the Internet Archive. Our cultural heritage is now taking digital form, whether born digital or born-again by conversion to digital from other media. San Francisco, authors are directors of the Internet Archive. School of Information and Management Systems 2-hydroxyglutarate peak: resonates at 2.Archiving Digital Cultural Artifacts: Organizing an Agenda for ActionĪrchiving Digital Cultural Artifacts Organizing an Agenda for Action.arterial spin labeling (ASL) MR perfusion.dynamic contrast enhanced (DCE) MR perfusion.dynamic susceptibility contrast (DSC) MR perfusion.metal artifact reduction sequence (MARS).turbo inversion recovery magnitude (TIRM).fluid attenuation inversion recovery (FLAIR).diffusion tensor imaging and fiber tractography.MRI pulse sequences ( basics | abbreviations | parameters).iodinated contrast-induced thyrotoxicosis.iodinated contrast media adverse reactions.clinical applications of dual-energy CT.as low as reasonably achievable (ALARA). ![]() faint grid lines present on an image, with no grid cut off.loss of contrast in areas of different pixel density yet not change in density can be seen i.e.tighter digital collimation in conjunction with reprocessing will correctly assign the correct values of interest.this is often due to a largely collimated area of smaller anatomy i.e.image appears washed out and underexposed.often a computer error often fixed with recollimation post exam (this should be explored before re-examination).the digital image often will have obscurely shaped, tight collimation that defies logic.similar to ghosting, however, the digital detector not being calibrated when promoted is the cause.failure of detector offset correction 4.this artifact should be carefully examined, if it does not interfere with the anatomy, it is not a detector failure/grid cut off, rather a limitation of the detector calibration.faint radiopaque striping (often vertical) in the background of an image, yet not evident on the anatomy.large areas of signal loss, due to detector drop.occur when two separate DR/CR (digital/computed radiography) images are merged into a single image (see case 3).increased radiation exposure required for portable DR (digital radiography) examinations.electronics are visible on the exposed image.latent image from previous exposure present on current exposure.fixer splashed on film prior to developing.air bubbles sticking to film during processing.black “lightning” marks resulting from films forcibly unwrapped or excessive flexing of the film.malfunction of the machine or placing the film in the fixer before developer solution.debris in the housing caused by the collimator tube can cause small trapezoidal regions, indicative of lead shavings.radiopaque objects on/external to the patient (e.g.superimposition of two structures from different locations due to double exposure of same film/plate.image compositing (or twin/double exposure).due to patient movement resulting in a distorted image.patient movement while taking the imageĬommon artifacts (all forms of radiography). ![]()
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