Chicago's central business district has the second-largest concentration of office space in North America.

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Ventilation dilutes the concentration of infectious particles within any confined space, thereby reducing the probability of infection.

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And their vertical concentration, necessary for any long term player in this space, is excellent.

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This book by Sivers, on the other hand, astonished me with the sheer concentration of fresh insights on business and entrepreneurialism, in such a small space.

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