A method for joining two components includes positioning a thermoplastic polymer portion of a first component adjacent a thermoplastic polymer portion of a second component such that the first and second portions form an interface. The method includes generating a beam of incident electrons using an electron source, biasing the specimen with respect to the electron source such that the incident electrons decelerate as a surface of the specimen is approached, and illuminating a portion of the specimen at a tilt with the beam of incident electrons. The removable compartments each have a plurality of flat wall sections which are assembled to form a structure which contains the plant roots during growth. The housing includes a first surface at least partly surrounding the keyboard and touch-based input, and a second opposing surface.