Abstract: A heating apparatus can have a sealed combustion chamber. A burner and an air shutter can be within the sealed combustion chamber. An air shutter control can be outside of the sealed combustion chamber. The air shutter control can provide fine tuning adjustment of the air shutter.

Abstract: A heat engine can have a fuel selector valve for selecting between a first fuel and a second fuel. Making the selection with the fuel selector valve can also determine a flow path through the heat engine, there being two different paths, each configured for a different fuel. A burner nozzle can form a single unit with the fuel selector valve. In some embodiments the burner nozzle can also form a single unit with an outlet valve.

Abstract: A valve assembly can include a housing, which can define a first fuel input for receiving a first fuel from a first fuel source and a second fuel input for receiving a second fuel from a second fuel source. The housing can define a first fuel output for directing fuel toward a control valve, and can define a third fuel input for receiving a portion of either the first fuel or the second fuel from the control valve. The housing can define a first egress flow path and a second egress flow path, each for directing fuel to the burner. In certain embodiments, the apparatus includes a valve body configured to selectively permit fluid communication between the first and second inputs and the output and between the third input and the egress flow paths.

Abstract: A heater assembly can be used with a gas appliance. The gas appliance can be a dual fuel appliance for use with one of a first fuel type or a second fuel type different than the first. The heater assembly can include at least one pressure regulator, a housing, and an actuation member. The housing has a first fuel hook-up for connecting the first fuel type to the heater assembly, a second fuel hook-up for connecting the second fuel type to the heater assembly, and an internal valve. The actuation member can control the position of the internal valve based on whether the first or the second fuel hook-up is used.

Abstract: A heater can be configured to operate with either a first fuel at a first pressure or a second fuel at a second pressure. In some embodiments, a pressure regulator unit is configured to regulate the pressure of either the first fuel or the second fuel and to direct either the first fuel or the second fuel towards a combustion chamber. A nozzle assembly can be configured to inject the fuel into the combustion chamber.

Abstract: A simulated flame fireplace comprising a fireplace housing, a heating apparatus, and an apparatus that generates simulated flames. The apparatus that generates simulated flames comprises at least one movable member with a plurality of light sources attached to it. When the apparatus is active, the light sources are configured to vary in intensity as the at least one member moves such that the plurality of light sources generates an appearance of flames.

Abstract: A dual fuel heating apparatus can include a safety control system having a shutoff valve, a thermocouple solenoid assembly, a first nozzle, and a second nozzle. The first nozzle can be positioned to direct heat from combustion of a first gas, liquid, or combination thereof towards the thermocouple solenoid assembly when the first gas, liquid, or combination thereof is being combusted. The second nozzle can be positioned to direct heat from combustion of a second gas, liquid, or combination thereof towards the thermocouple solenoid assembly when the second gas, liquid, or combination thereof is being combusted. The thermocouple solenoid assembly can be configured to maintain the shutoff valve in an open position based on heat from combustion directed to the thermocouple solenoid assembly or in a closed position based on an absence of heat from combustion directed to the thermocouple solenoid assembly.

Abstract: In certain embodiments, an apparatus can comprise a dual fuel pilot assembly. The pilot assembly can comprise a first fuel dispenser, a second fuel dispenser, an igniter and at least one of a thermocouple, and a thermopile. The pilot assembly can be configured to direct heat from combustion of one of either a first fuel or a second fuel to the at least one of the thermocouple and the thermopile.

Abstract: A heating system can include certain pressure sensitive features. These features can be configured to change from a first position to a second position based on a pressure of a fuel flowing into the feature. These features can include, fuel selector valves, pressure regulators, burner nozzles, and oxygen depletion sensor nozzles, among other features.

Abstract: A dual fuel heater can couple with one of two fuel sources operating at different pressures. The dual fuel heater can have a first fuel line, a second fuel line, a fluid flow controller, and a combustion chamber. The fluid flow controller can selectively permit flow of a first fuel to either the first fuel line or flow of a second fuel to the second fuel line. The first fuel line can be in communication with a first oxygen depletion sensor orifice and the second fuel line can be in communication with a second oxygen depletion sensor orifice.

Abstract: A method for determining a concentration of an analyte is disclosed. The method includes applying a potential excitation to a fluid sample containing an analyte and determining if a current decay curve associated with the fluid sample has entered an analyte depletion stage. The method also includes measuring a plurality of current values associated with the fluid sample during the analyte depletion stage and calculating an analyte concentration based on at least one of the plurality of current values.

Abstract: Disclosed herein are methods for identifying rare cells containing particular markers and/or alleles from biological samples that have not been substantially pre-processed (e.g., unprocessed whole blood). The methods described herein provide a system for digital enrichment of target cells from a biological sample and detection of such target cells, thereby allowing accurate and efficient detection and/or enumeration of such cells in the sample.

Abstract: In certain embodiments, an apparatus includes a control valve for regulating fuel flow. The apparatus can include a burner and a valve assembly. In some embodiments, the valve assembly includes a housing, which can define a first fuel input for receiving a first fuel from a first fuel source and a second fuel input for receiving a second fuel from a second fuel source. The housing can define a first fuel output for directing fuel toward the control valve, and can define a third fuel input for receiving a portion of either the first fuel or the second fuel from the control valve. The housing can define a first egress flow path and a second egress flow path, each for directing fuel to the burner. In certain embodiments, the apparatus includes a valve body configured to selectively permit fluid communication between the first and second inputs and the output and between the third input and the egress flow paths.

Abstract: A heater can be configured to operate with either a first fuel at a first pressure or a second fuel at a second pressure and can include an elongated tubular combustion chamber, a first combustion chamber nozzle outlet, a second combuston chamber nozzel outley, and a fluid flow controller. In some embodiments, the fluid flow controller is configured to direct the first fuel to the first combustion chamber nozzle outlet and then to the second combustion chamber nozzle ourlet when the controller is in a first position. In a second position, the fluid flow controller is configured to direct the second fuel to the second combustion chamber nozzle outlet.

Abstract: A heating system can include certain pressure sensitive features. These features can be configured to change from a first position to a second position based on a pressure of a fuel flowing into the feature. These features can include, fuel selector valves, pressure regulators, burner nozzles, and oxygen depletion sensor nozzles, among other features.

Abstract: A heating apparatus can be a dual heating power source or a hybrid heater. For example, the heating apparatus can include a fuel delivery system for combusting a gas fuel and a separate electronic heater. Other types of heating sources or methods can also be used to provide the heating apparatus with more than one heating source and/or heating method. The heating apparatus can also include one or more air flow channel to facilitate efficient heating of air flow through the heating apparatus.

Abstract: A dual fuel heater can couple with one of two fuel sources operating at different pressures. The dual fuel heater can have a first fuel line, a second fuel line, a fluid flow controller, and a combustion chamber. The fluid flow controller can selectively permit flow of a first fuel to either the first fuel line or flow of a second fuel to the second fuel line. The first fuel line can be in communication with a first oxygen depletion sensor orifice and the second fuel line can be in communication with a second oxygen depletion sensor orifice.

Abstract: A biosensor having a first conductive component is described, wherein the first conductive component includes at least one boundary formed by a first processing technique and at least one boundary formed by a second processing technique not the same as the first processing technique. The biosensor can also have a second conductive component including at least one boundary formed by the first processing technique and at least one boundary formed by a third processing technique not the same as the first processing technique. Further, the biosensor has a third conductive component including at least one boundary formed by the second processing technique and at least one boundary formed by the third processing technique not the same as the second processing technique.

Abstract: In certain embodiments, an apparatus includes a burner. The apparatus can also include an intake valve that includes an input for receiving fuel from either a first fuel source at a first pressure or a second fuel source at a second pressure. The intake valve can include a first output for directing fuel received from the first fuel source and a second output for directing fuel received from the second fuel source. The intake valve can include an actuator configured to permit fluid communication between the input and the first output or between the input and the second output. The apparatus can include a pressure regulator that can include a first inlet for receiving fuel from the first output of the intake valve and a second inlet for receiving fuel from the second output of the intake valve. The regulator can also include an outlet for directing fuel from the pressure regulator toward the burner.

Abstract: A heater can be configured to operate with either a first fuel at a first pressure or a second fuel at a second pressure and can include a fluid flow controller. In some embodiments, the fluid flow controller is configured to permit flow of fuel to a first passageway and to direct a first fuel to a first oxygen depletion sensor line when the controller is in a first position and permit the flow of fuel to a second passageway and to direct a second fuel to a second oxygen depletion sensor line when the controller is in a second position.