Abstract: A liquid chromatographic system includes columns, column mounting fixtures to which the columns are mounted, a detector, a collector, a controller and a plurality of RFIDs. A first RFID communicates with the controller and cooperating RFIDs mounted to other components provide information such as the history of components, parameters and the like. They also receive information from sensors relating to the operation of the liquid chromatograph, store the information and transmit it. Moreover, the RFIDs may substitute for hard wiring in many applications and may enable a central computer to control several liquid chromatographic systems.

Abstract: A liquid chromatographic system includes columns, column mounting fixtures to which the columns are mounted, a detector, a collector, a controller and a plurality of RFIDs. A first RFID communicates with the controller and cooperating RFIDs mounted to other components provide information such as the history of components, parameters and the like. They also receive information from sensors relating to the operation of the liquid chromatograph, store the information and transmit it.

Abstract: A chromatographic monitor includes an array of flow cells with individual light sensors that are collectively an array of photodiodes. The output from the photodiodes are multiplexed. To prevent losing information, the photodiodes are each connected to a different one of a plurality of inputs to the multiplexer through a corresponding one of a plurality of circuits that stores energy during the time the one inlet is not connected through the multiplexer to the signal processing circuitry that forms a part of an absorbance monitor. Preferably, the energy storing circuit is a non-switching circuit with low bandwidth and a flat-topped response to an impulse. This improves the signal to noise ratio. A one pole low pass filter with a (1-1/e) Dirac pulse fall time and equal to the multiplex entire cycle repeat time can perform this function and a one pole low pass filter provides satisfactory results.

Abstract: An isocratic gradient profile is inserted into a gradient profile during a flash chromatographic run when TLC indicates that it will be difficult to separate the component being purified from its closest impurity by a gradient. TLC is utilized to determine at least two retention factors with two significantly different solvent strengths for the same solvent system. The two or more retention factors are used to determine a solvent strength in which the retention factor of a target component and the retention factor of a closest impurity are within 0.8 of each other. The isocratic gradient profile is started when this solvent strength is reached during the gradient chromatographic run.

Abstract: An intramedullary nail for use in a medullary canal of a long bone is provided. The nail includes a body defining a longitudinal axis of the body and an external periphery of the body for fitting in the medullary canal of the long bone. The body has a first internal wall thereof defining a first opening through the body. The first opening defines a first opening centerline. The body has a second internal wall of the body defining a second opening through the body. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other. The longitudinal axis of the body and the first opening centerline form an acute angle between the longitudinal axis of the body and the first opening centerline. The longitudinal axis of the body and the second opening centerline forming an acute angle between the longitudinal axis of the body and the second opening centerline.

Abstract: An intramedullary nail for use in a medullary canal of a long bone is provided. The nail includes a body defining a longitudinal axis and an external periphery of the body for fitting in the medullary canal of the long bone. The body has a first internal wall of the body defining a first opening through the body, the first opening defines a first opening centerline. The body has a second internal wall of the body defining a second opening through the body. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other.

Abstract: An intramedullary nail for use in a medullary canal of a long bone is provided. The nail includes a body defining a longitudinal axis and an external periphery of the body for fitting in the medullary canal of the long bone. The body has a first internal wall of the body defining a first opening through the body. The first opening defines a first opening centerline. The body has a second internal wall of the body defining a second opening through the body. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other. At least one of the first opening centerline and the second opening centerline are transverse to the longitudinal axis of said body.

Abstract: An intramedullary nail for use in a medullary canal of a long bone is provided. The nail includes a body defining a longitudinal axis and an external periphery of the body for fitting in the medullary canal of the long bone. The body has a first internal wall of the body defining a first opening through the body. The first opening defines a first opening centerline. The body has a second internal wall of the body defining a second opening through the body. The second opening defines a second opening centerline. The first opening centerline and the second opening centerline are oblique with respect to each other. The first opening centerline and the longitudinal axis of said body form an acute angle between the first opening centerline and the longitudinal axis.

Abstract: A chromatographic monitor includes an array of flow cells with individual light sensors that are collectively an array of photodiodes. The output from the photodiodes are multiplexed. To prevent losing information, the photodiodes are each connected to a different one of a plurality of inputs to the multiplexer through a corresponding one of a plurality of circuits that stores energy during the time the one inlet is not connected through the multiplexer to the signal processing circuitry that forms a part of an absorbance monitor. Preferably, the energy storing circuit is a non-switching circuit with low bandwidth and a flat-topped response to an impulse. This improves the signal to noise ratio. A one pole low pass filter with a (1-1/e) Dirac pulse fall time and equal to the multiplex entire cycle repeat time can perform this function and a one pole low pass filter provides satisfactory results.

Abstract: A chromatographic monitor includes an array of flow cells with individual light sensors that are collectively an array of photodiodes. The output from the photodiodes are multiplexed. To prevent losing information, the photodiodes are each connected to a different one of a plurality of inputs to the multiplexer through a corresponding one of a plurality of circuits that stores energy during the time the one inlet is not connected through the multiplexer to the signal processing circuitry that forms a part of an absorbance monitor. Preferably, the energy storing circuit is a non-switching circuit with low bandwidth and a flat-topped response to an impulse. This improves the signal to noise ratio. A one pole low pass filter with a (1-1/e) Dirac pulse fall time and equal to the multiplex entire cycle repeat time can perform this function and a one pole low pass filter provides satisfactory results.

Abstract: To economically perform preparatory chromatography, a plurality of pumps each having a corresponding one of a plurality of pistons and a corresponding one of a plurality of cylinders are driven by one motor to draw and pump solvent simultaneously into corresponding columns. To form a gradient, the pumps are connected to two-way valves that are connected alternately to a first solvent and a second solvent, whereby the time said valve is in a first position controls the amount of solvent drawn from the first reservoir into said pumps and the amount of time in said second position controls the amount of said second solvent drawn from the second reservoir into said pumps and the solvent is mixed in the pumping systems. The detectors are photodiodes mounted to light guides in the flow cells that generate signals related to light absorbance and communicate with a controller, whereby the controller receives signals indicating solute between the light guides and causes collection of solute.

Abstract: A bubbler is positioned within a solvent reservoir of a chromatographic system with its opening near the bottom of the system to measure the pressure of solvent. The bubbler may use air or may use helium or some other gas so that the solvent can be purged of excess air while its level is being monitored by the bubbler. The bubbler provides a depth signal to a microcontroller that records the drop in pressure and projects a low level of pressure at which point solvent should be replenished. The microprocessor may provide a signal to the operator or terminate operation or automatically replenish solvent depending upon the program.

Abstract: To make an inexpensive chromatographic column and perform chromatography with it, column walls and a column end with a port are molded integrally from plastic. A closure is integrally molded with a port as well. One type of closure includes part of a snap-on fastener integrally molded to it to cooperate with corresponding parts molded integrally with the column walls and another type of closure is welded to the tubular walls. In the preferred embodiment the welding is spin welding. The end and closure have channels molded into them radiating from a port and opening toward packing material such as silica beads or porous polymeric plugs. Filters and secondary seals may be located at the ends to prevent leakage of packing material.

Abstract: To make an inexpensive chromatographic column and perform chromatography with it, column walls and a column end with a port are molded integrally from plastic. A closure is integrally molded with a port as well. One type of closure includes part of a snap-on fastener integrally molded to it to cooperate with corresponding parts molded integrally with the column walls. In another type of closure for higher pressures, the closure is spin welded to the tubular walls. In still another type of closure for still higher pressures, a retaining plate is pressed into the column to hold the packing in place. The closures have channels molded into them radiating from a port and opening toward packing material such as silica beads or porous polymeric plugs. Filters and secondary seals may be located at the ends to prevent leakage of the packing material.

Abstract: A chromatographic monitor includes an array of flow cells with individual light sensors that are collectively an array of photodiodes. The output from the photodiodes are multiplexed. To prevent losing information, the photodiodes are each connected to a different one of a plurality of inputs to the multiplexer through a corresponding one of a plurality of circuits that stores energy during the time the one inlet is not connected through the multiplexer to the signal processing circuitry that forms a part of an absorbance monitor. Preferably, the energy storing circuit is a non-switching circuit with low bandwidth and a flat-topped response to an impulse. This improves the signal to noise ratio. A one pole low pass filter with a (1?1/e) Dirac pulse fall time and equal to the multiplex entire cycle repeat time can perform this function and a one pole low pass filter provides satisfactory results.

Abstract: To make an inexpensive chromatographic column and perform chromatography with it, column walls and a column end with an inlet port are molded integrally from plastic and a snap-on end is molded integrally with an outlet port from plastic. A filter is placed in one end of the column and the column is filled with packing material up to the second end. A filter is placed on top of the packing and a snap-on end with a molded outlet port is snapped onto the body with linear motion until an interference fit is formed. As the body and snap-on end are moved together cantilever members formed integrally with the snap on end are bent outwardly by detent members until the detent members are captured by an opening in the cantilever members.

Abstract: To economically perform preparatory chromatography, a plurality of pumps each having a corresponding one of a plurality of pistons and a corresponding one of a plurality of cylinders are driven by one motor to draw and pump solvent simultaneously into corresponding columns. To form a gradient, the pumps are connected to two-way valves that are connected alternately to a first solvent and a second solvent, whereby the time said valve is in a first position controls the amount of solvent drawn from the first reservoir into said pumps and the amount of time in said second position controls the amount of said second solvent drawn from the second reservoir into said pumps and the solvent is mixed in the pumping systems. The detectors are photodiodes mounted to light guides in the flow cells that generate signals related to light absorbance and communicate with a controller, whereby the controller receives signals indicating solute between the light guides and causes collection of solute.

Abstract: To perform density gradient separation, density gradient columns are prepared at a central location and frozen. They are then taken to other locations while frozen and heated to return the mobility of the density gradient solutions. In this manner, the density gradient solutions can be preserved during travel and for a long period of time, thus removing the need for forming the density gradient solutions at the sites they are to be used and at the time of use and avoiding the need for the purchase of specialized gradient forming equipment in some facilities that use solvent gradient density separations.

Abstract: In a distal targeting system a hand-held location pad is integral with a guide section for a drill or similar surgical instrument, and has a plurality of magnetic field generators. A sensor, such as a wireless sensor, having a plurality of field transponders, is disposed in an orthopedic appliance, such as an intramedullary nail. The sensor is capable of detecting and discriminating the strength and direction of the different fields generated by the field generators. Control circuitry, preferably located in the location pad is responsive to a signal of the sensor, and determines the displacement and relative directions of an axis of the guide section, and a bore in the orthopedic appliance. A screen display and optional speaker in the location pad provide an operator-perceptible indication that enables the operator to adjust the position of the guide section so as to align its position and direction with the bore.

Abstract: To economically perform preparatory chromatography, a plurality of pumps each having a corresponding one of a plurality of pistons and a corresponding one of a plurality of cylinders are driven by one motor to draw and pump solvent simultaneously into corresponding columns. To form a gradient, the pumps are connected to two-way valves that are connected alternately to a first solvent and a second solvent, whereby the time said valve is in a first position controls the amount of solvent drawn from the first reservoir into said pumps and the amount of time in said second position controls the amount of said second solvent drawn from the second reservoir into said pumps and the solvent is mixed in the pumping systems. The detectors are photodiodes mounted to light guides in the flow cells that generate signals related to light absorbance and communicate with a controller, whereby the controller receives signals indicating solute between the light guides and causes collection of solute.