One of the 74,771 articles currently pinpointed by Deja Vu is a 2006 paper by Ebtekar on cytokines and air pollution published in English by the Iranian Journal of Allergy, Asthma and Immunology.
A facial expression is one or more motions or positions of the muscles beneath the skin of the face.According to one set of controversial theories, these movements convey the emotional state of an individual to observers. Facial expressions are a form of nonverbal communication.acial expressions are vital to social communication between humans. They are caused by the movement of muscles that connect to the skin and fascia in the face. These muscles move the skin, creating lines and folds and causing the movement of facial features, such as the mouth and eyebrows.
A smile is a facial expression formed primarily by flexing the muscles at the sides of the mouth. Some smiles include a contraction of the muscles at the corner of the eyes, an action known as a Duchenne smile. smile seems to have a favorable influence upon others and makes one likable and more approachable. In the social context, smiling and laughter have different functions in the order of sequence in social situations: