Reference 1

Smart, L., Kubzansky, L., Maselko, J., Kawachi, I., Choo, P., & Bauer, M.
     (2005). Positive Emotion and Health: Going Beyond the Negative. Health 
     Psuchology, 24(4), 422-429. doi:10.1037/0278-6133.24.4.422
       

       This article is describe a correlational study between positive
       emotions, specifically curiosity and hope, with the changes in the immune
       system consering about three disease outcome.
  
       Statistics from the research showed that:
       1. No differences were found between ages.
       2. Higher levels of curiosity were more common in males.
       3. The socioeconomic status was related in an increasing bilateral
       way with the presence of both curiosity and hope emotions.
  
       The authors concluded that both curiosity and hope influence in
       a healthy way the main physiological systems and could work like a
       preventive factor for disease development.
  
       This article is useful because they made a study that relates
       some emotions to the immunology system and is an adequate resource to
       sustent my research.

Hope