Then he remembered that there are natural phenomena to which some one has given the name "
acoustic shadows." If you stand in an
acoustic shadow there is one direction from which you will hear nothing.
The vertical structure behind the dot is the
acoustic shadow from the solder bump, which reflected ultrasound back to the transducer and thus cast an
acoustic shadow downward.
[19] The implant is visible in the transverse plane by its characteristic posterior
acoustic shadow. [20] Simultaneously, the depth of the implant can be determined.
Such air defects, whose size a is larger than the focal spot dF of the probe ultrasound beam (a^lOdf), generate an
acoustic shadow in the volume under the inclusion.
Plain radiography did not give any appreciable diagnosis, but ultrasonography showed hyperechoic area with distal cast
acoustic shadow, but was also obscured by even a small volume of luminal gas.
It also includes aspects of technology, culture, and physical phenomena that influenced the outcomes or documentation of the war, such as the early ambrotype photograph, influential newspapers, the practice on conscription, and the phenomenon of
acoustic shadow. Over 2500 entries are collected, with most spanning half a page to a page with cross-references and selected sources.
Barriers protect the receiver from direct airborne sound waves by reducing the noise level in the
acoustic shadow zone.
The maximum diameter of the SCV and the distance between its upper border and the superior margin of the clavicle were measured at the site where the two structures were closest (at this site the SCV is even closer to the inferior border of the clavicle but this region is obscured by an
acoustic shadow).
Entertainment was provided by Michael and Leigh Ann Carley of
Acoustic Shadow and Rain Jaudon and Cheri Salvetti of Rhythm and Rain.
Millili stated, "Regardless of observer experience in burn evaluation, obliteration of the dermal/fat interface and widening of the dermal
acoustic shadow provides reliable markers of deep thermal injury." Deep dermal injuries are best treated with immediate excision and grafting, where superficial injuries are best treated conservatively.