Abstract: Described herein are retention devices and their use to limit the accessible length of an elongated object, where unfettered access to the full length of the elongated object would pose a safety hazard. In some exemplary embodiments an animal safety device is disclosed that clamps onto an elongated chewable object so as to provide an animal (e.g., a domesticated animal such as a dog) a segment of chewable material while avoiding a choking hazard.

Abstract: Sub-ducts and methods of exhausting into a generally rectangular and vertical main shaft are disclosed herein. A sub-duct of one embodiment includes hollow first and second portions. The first portion presents a generally flat attaching wall, a top side that defines an opening, and a bottom side that has an aerodynamic configuration; the second portion defines an intake opening, meets with the first portion attaching wall at approximately a ninety degree angle, and has a configuration complementary to a configuration of an exhaust duct. The first and second portions collectively define a continuous channel between the intake opening and the top side opening. The first portion may have a section of generally constant cross section extending from adjacent the second portion to the top side opening, and the second portion may have a generally constant cross section extending from the intake opening to the first portion.

Abstract: An improved optical beam integration system for homogenizing a nonuniform radiant energy beam having a nonuniform beam intensity profile characteristic. The optical beam integration system comprises a first crossed lenticular cylindrical lens structure, a second crossed lenticular cylindrical lens structure, and a focusing lens interposed between a radiant energy source and an image or work plane. The nonuniform radiant energy beam from the radiant energy source refracts sequentially through the first and second crossed lenticular cylindrical lens structures and the focusing lens so as to produce a homogenized beam which forms an image in the work plane. The work plane is at a constant distance from the optical beam integration system. Preferably, the optical beam integration system is adjustable for selectively setting the size of the image produced by the homogenized beam in the work plane.