Abstract: A gas lift system for lifting oil with a production tube positioned inside a well casing with manifolds in the production tube spaced apart from each other; the system including valve assemblies on the manifolds that each have an open position and a closed position, each of the valve assemblies including a biasing device that biases the valve towards the closed position, where pressurizing each valve assembly with a control fluid generates a force that acts against the biasing force of the biasing device to open the valve, and a means to selectively control the pressure of the control fluid in the control line, where each of the valve assemblies includes different biasing forces in each valve, with a topmost valve having a highest biasing force and each sequentially lower valve having a lower biasing force. A method for using the gas lift system is also included.

Abstract: A gas lift system for lifting oil with a production tube positioned inside a well casing with manifolds in the production tube spaced apart from each other; the system including valve assemblies on the manifolds that each have an open position and a closed position, each of the valve assemblies including a biasing device that biases the valve towards the closed position, where pressurizing each valve assembly with a control fluid generates a force that acts against the biasing force of the biasing device to open the valve, and a means to selectively control the pressure of the control fluid in the control line, where each of the valve assemblies includes different biasing forces in each valve, with a topmost valve having a highest biasing force and each sequentially lower valve having a lower biasing force. A method for using the gas lift system is also included.

Abstract: A variable view arthroscope includes a tubular housing having a longitudinal axis and an input end, an input lens and a CCD in the input end of the housing for capturing and relaying an image object. In some embodiments, a variable view arthroscope with a plurality of viewing positions in a viewing range between a first end viewing position and a second end viewing position includes a tubular housing having a longitudinal axis and an input end, an input lens and a mirror in the housing for obtaining an image object, and a prism, a focusing lens, and a CCD in the housing for capturing and relaying the image object. The input lens and mirror are movable around an axis for varying the view of the arthroscope. In certain embodiments, the tubular housing has a longitudinal axis and an input end and the input lens and CCD are mounted in an input lens holder in the input end of the housing. The input lens and the CCD are movable for varying the view of the arthroscope.