Astronomers examined Signe's orbit to determine its long-term stability.

The club announced several high-profile signings ahead of the transfer deadline.

The email list contained several at signs that needed to be corrected.

I found several misplaced at-signs in the draft and corrected them before sending the newsletter.

We followed the direction sign to the museum and arrived just in time.

To assess for hypocalcemia, the clinician elicited Trousseau's sign by inflating a blood pressure cuff around the patient's arm, which induced a characteristic spasm of the hand and forearm.

During the consultation, the patient produced a matchbox sign, presenting a small container filled with fibers he insisted had crawled from his skin.

The chest radiograph demonstrated a Westermark sign, a focal area of oligemia distal to a pulmonary embolism.

The emergency physician noted a positive Blumberg sign during the abdominal exam, which raised concern for peritonitis.

The new road sign warned drivers of the sharp curve ahead.