Said of a semiconductor diode, p-n junction, or the emitter-base junction of a transistor, when the polarity of the applied emf is such as to allow substantial conduction to take place, 1  TRANSISTOR.  PNP TRANSISTOR, P-N-P TRANSISTOR.
The symptoms of mold allergy are very similar to the symptoms of other allergies, such as sneezing, itching, runny nose, congestion and dry, scaling skin. Outdoor molds may cause allergy symptoms in summer and fall (or year-round in some climates)
If you have an allergy to mold, you likely will not be allergic to all types of mold. Mold spores have only limited similarities, and your body probably will only be sensitive to some of them. People in some occupations have more exposure to mold and are at greater risk of developing a mold allergy.