In environmental science, experimental design is an extremely important part of the scientific method. When a scientist seeks to prove or disprove a hypothesis, he or she must carefully design the experiment so that it tests only one thing, or variable.
Borderline personality disorder (BPD), also known as emotionally unstable personality disorder, is a long term pattern of abnormal behavior characterized by unstable relationships with other people, unstable sense of self, and unstable emotions.
borderline personality disorder. n. Abbr. A personality disorder characterized by impulsiveness and by a long-standing pattern of instability in interpersonal relationships, behavior, mood, and self-image, with symptoms often including intense anger and fear of abandonment.