Expanded uncertainty. quantity defining an interval about the result of a measurement that may be expected to encompass a large fraction of the distribution of values that could reasonably be attributed to the measurand.
Introduction. 'Phantosmia' is the medical term for an imaginary odour (phantom smell) . It is also known as an olfactory hallucination. The smell is unique to the person and is usually unpleasant, spoiling the taste of any food or drink consumed.It can be in one or both nostrils.ess commonly, the cause of phantosmia is either nerve cells sending abnormal smell signals to the brain, or a problem with the brain itself. This may be the result of: 1  a disease affecting the nervous system, such as epilepsy, Parkinsonâs disease or Alzheimerâs disease. 2  a stroke.
Astigmatism is an eye condition with blurred vision as its main symptom. The front surface of the eye (cornea) of a person with astigmatism is not curved properly-the curve is irregular-usually one half is flatter than the other-sometimes one area is steeper than it should be.When light rays enter the eye they do not focus correctly on the retina, resulting in a blurred image.auses of astigmatism. Corneal astigmatism. The cornea is a clear (transparent) layer of tissue that covers the front of the eye. As well as transmitting and focusing light into the eye, it protects the eye from infection and damage.