Examlex
The period of variability of a Cepheid variable star, which is easily measured, is directly related to which stellar parameter, thereby providing a reliable method for the measurement of distance to stars?
Ethnic Differences
Variations in practices, traditions, and behaviors among groups of people identified by shared ancestry, culture, or nationality.
Autism
An autism spectrum disorder characterized by extreme aloneness, communication problems, intolerance of change, and ritualistic behavior.
Childhood Disintegrative Disorder
A rare condition characterized by late onset (at least after two years of normal development) of developmental delays in language, social function, and motor skills.
Asperger's Disorder
A former diagnostic category denoting a higher-functioning form of autism characterized by significant difficulties in social interaction and nonverbal communication, alongside restricted and repetitive patterns of behavior and interests.
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