The lack of meaningful interaction between the two, however, is a reason for the limited progress at this point.

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Even in highly populated urban areas, there are elderly-rich communities where members are living alone and suffering from a lack of social interaction.

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Most frequently cited is the lack of social interaction.

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Officials have been able to conclude that the dolphins' deaths were not due to lack of food, interaction with fisheries, poisoning with pesticides, biotoxin poisoning or contamination by heavy metals.

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"The physical environment of the emergency room is famous for lack of privacy, for loud, confusing sounds and for very rapid and changing staff interaction, " says Dr. Thomas, a professor at the Erickson School at the University of Maryland, Baltimore County.

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