Abstract: A packer system including a packer and a setting mechanism. The setting mechanism has a setting piston that is actuatable in response to a fluid pressure in order to set the packer with the setting piston. The setting mechanism prevents actuation of the setting piston until the pressure is decreased below a threshold pressure from a value greater than the threshold pressure. A method of setting a packer is also included.

Abstract: A combinatorial microenvironment generator is configured for the generation of arbitrary, user-defined, steady-state, concentration gradients with negligible to no flow through the growth medium to perturb diffusion gradients or cellular growth. More importantly, the absolute concentrations and/or gradients can be dynamically altered upon request both spatially and temporally to impose tailored concentration fields for in-situ stimulus studies. Here, diffusion occurs via an array of ports, each of which can be an independently controlled source/sink. Together, the array of ports establishes a user-defined, 3D concentration profile. Useful methods related to this device are also provided.

Abstract: A packer system including a packer and a setting mechanism. The setting mechanism has a setting piston that is actuatable in response to a fluid pressure in order to set the packer with the setting piston. The setting mechanism prevents actuation of the setting piston until the pressure is decreased below a threshold pressure from a value greater than the threshold pressure. A method of setting a packer is also included.

Abstract: A combinatorial microenvironment generator is configured for the generation of arbitrary, user-defined, steady-state, concentration gradients with negligible to no flow through the growth medium to perturb diffusion gradients or cellular growth. More importantly, the absolute concentrations and/or gradients can be dynamically altered upon request both spatially and temporally to impose tailored concentration fields for in-situ stimulus studies. Here, diffusion occurs via an array of ports, each of which can be an independently controlled source/sink. Together, the array of ports establishes a user-defined, 3D concentration profile. Useful methods related to this device are also provided.

Abstract: Micro-electro-mechanical (MEM) translational tabs are introduced for enhancing and controlling aerodynamic loading of lifting surfaces. These microtabs are mounted at or near the trailing edge of lifting surfaces, deploy approximately normal to the surface, and have a maximum deployment height on the order of the boundary layer thickness. Deployment of this type of device effectively changes the camber, thereby affecting the lift generated by the surface. The effect of these microtabs on lift is as powerful as conventional control surfaces such as ailerons. Application of this simple yet innovative lift enhancement and control device will permit the elimination of some of the bulky conventional high-lift and control systems and result in an overall reduction in system weight, complexity and cost.

Abstract: Micro-electro-mechanical (MEM) translational tabs are introduced for enhancing and controlling aerodynamic loading of lifting surfaces. These microtabs are mounted at or near the trailing edge of lifting surfaces, deploy approximately normal to the surface, and have a maximum deployment height on the order of the boundary layer thickness. Deployment of this type of device effectively changes the camber, thereby affecting the lift generated by the surface. The effect of these microtabs on lift is as powerful as conventional control surfaces such as ailerons. Application of this simple yet innovative lift enhancement and control device will permit the elimination of some of the bulky conventional high-lift and control systems and result in an overall reduction in system weight, complexity and cost.

Abstract: A wafer level interconnecting mechanism for assembling and packaging multiple MEMS devices (modules), using microfabricated, interlocking, mechanical joints to interconnect different modules and to create miniature devices. Various devices can be fabricated using these joints, including fiber-optic switches, xyz translational stages, push-n-lock locking mechanisms, slide-n-lock locking mechanisms, t-locking joints, fluidic interconnects, on/off valves, optical fiber couplers with xy adjustments, specimen holders, and membrane stops.

Abstract: Low residual stress, stoichiometric or near stoichiometric, silicon nitride and silicon carbide films with thicknesses of one micron or greater are produced by reacting porous silicon with a nitrogen or carbon containing gas, such as ammonia or methane, at an appropriate temperature and pressure. The gas diffuses into the pores and reacts with the silicon skeletal structure. Because the initial structure is porous and the pore spaces provide strain relief during the addition reaction and subsequent volume expansion, the resultant film has relatively low residual stress. Either porous or solid films can be produced. This process provides a means to chemically stabilize porous silicon layers and their morphologies.

Abstract: An interferometric-based pressure transducer is fabricated from two layers of silicon having different crystal orientations which have been processed using selective anisotropic etching to produce in one silicon layer a mirror surface and a groove that is aligned with the mirror, and a pressure-responsive membrane in the other layer. The layers are joined with the membrane opposite the mirror, and an optical fiber is secured in the groove so that light from the optical fiber is conveyed by the mirror surface between the membrane and the optical fiber. Conventional interferometric apparatus compares transmitted and received light in order to sense deformation of the membrane and thereby sense pressure.

Abstract: Electrochemical microsensors formed of a substrate containing means for sensing potential or current, including active and passive electronic devices and electronic circuits, and a micromachined structure containing at least one cavity overlying the sensing means, wherein the structure and substrate are bonded together at a temperature less than about 400.degree. C., in the absence of high voltage fields, using means not requiring highly planarized surfaces. A wide variety of materials can be utilized for both the substrate and overlying structure.Diverse embodiments are possible, having in common a cavity containing a chemically sensitive material and means for sensing potential or current.The resulting structural organization of materials transduces a chemical signal, such as concentration, to an electrical signal, which is then "processed" by the underlying FET or metallic connections.