There are many types of artifacts, and they are commonly mistaken for ecofacts (such as discovered animal parts) and features (elements in the landscape that appear to be manmade, usually structural) all three can be discovered together at archaeological sites.Ī wide range of studies is carried out in order to better understand historical artifacts and subsequently offer information about them to the scientific and public worlds. Objects such as this bronze Scythian arrowhead can reveal a great deal about the societies that made and used them Stock image In various settings, the same thing may be labeled all or one of these, and more precise terminology will be used when discussing individual items or sets of related ones. In archaeology, the generic word is “artifact,” although in museums, the comparable broad term is usually “object,” and in art history, it might be artwork or a more specialized term like “carving. Archaeologists unearth ancient societies’ structures and utilize the historical artifacts discovered there to study and analyze the past.īecause many ancient societies did not actively document their histories, ancient world artifacts are often the only indications of how the people lived from day to day. Scholars who want to understand an ancient culture can benefit greatly from archaeological artifacts. 4.1 Which Item Is an Example of an Artifact?.1.1.1 Artifacts Are the Results of Behavioral and Transformative Processes.1.1 Which Item Is an Example of an Artifact?.propylene glycol peak: resonates at 1.13 ppm.N-acetylaspartate (NAA) peak: resonates at 2.0 ppm.glutamine-glutamate peak: resonates at 2.2-2.4 ppm.gamma-aminobutyric acid (GABA) peak: resonates at 2.2-2.4 ppm. 2-hydroxyglutarate peak: resonates at 2.25 ppm.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).Practical pointsĪlthough sometimes grouped with reverberation due to similar appearances, ring down artifact does not arise from the same mechanism and should be considered separately 3. With comet tail artifact, the space between the two strong parallel reflectors may be less than 1/2 the space pulse length, causing the echoes to be displayed as triangular lines (the later echoes get attenuated and have a decreased amplitude, manifesting on the display as decreased width). cholesterol crystals in adenomyomatosis). This results in a short train of reverberations from an echogenic focus which has strong parallel reflectors within it (e.g. Reverberation artifacts can be improved by changing the angle of insonation so that reverberation between strong parallel reflectors cannot occur.Ĭomet tail artifact is a specific type of reverberation artifact. When the ultrasound beam reflects back and forth between the reflectors ("reverberates"), the ultrasound transducer interprets the sound waves returning as deeper structures since it took longer for the wave to return to the transducer. Reverberation artifact occurs when an ultrasound beam encounters two strong parallel reflectors.
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