2. A vessel approaching a blind bend in a river can sound one prolonged blast on the ships' whistle to alert any other vessels to its presence, if another vessel is nearby then they will respond with one prolonged blast on the ships' whistle.
Atrial fibrillation, known as AF or Afib, is an irregular and often very fast heart rate. This may cause symptoms like heart palpitations, fatigue, and shortness of breath. Treating atrial fibrillation is important because it may cause a stroke and negatively impact your quality of life.
Symptoms of fibromyalgia include: 1  Widespread pain. The pain associated with fibromyalgia often is described as a constant dull ache that has lasted for at least three months. To be considered widespread, the pain must occur on both sides of your body and above and below your waist. 2  Fatigue.