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Christoph Bültemann
Köln, Nordrhein-Westfalen, Germany
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Aug. 17, 2025, 10:01 a.m. PDT
Seal Team Fix
registered for challenge
July 12, 2025, 12:57 p.m. PDT
Reducing Malaria in Homes with Improved Air Cavity Ventilation
registered for challenge
Nov. 14, 2024, 10:03 a.m. PST
Hardware-Free Horizons: The 2024 Ventora Innovation Challenge
registered for challenge
Sept. 27, 2024, 4:25 a.m. PDT
High-Tech Autonomous Bin Emptying System
registered for challenge
Oct. 24, 2020, 6:06 a.m. PDT
PLASTIKA REPARABILIS CHALLENGE
registered for challenge
Sept. 17, 2020, 4:57 a.m. PDT
Guardians of the Reservoir Challenge
registered for challenge
