Abstract: A drip chamber assembly that functions irrespective of its orientation and in the presence of increased internal pressure is provided.

Abstract: A method of operating an infusion pump includes transmitting light through or around a drop of fluid suspended from an end of a drip tube for the infusion pump, the end of the drip tube located in a drip chamber for the infusion pump, wherein the drip tube is configured for connection to a source of the fluid; receiving, using an optical system for the pump, light transmitted through or around the drop; transmitting, to a specially programmed microprocessor and using the optical system, data regarding the received light; and, using the microprocessor to calculate a volume of the drop using the data.

Abstract: A piercing part for a medical infusion system includes a housing with a piercing mandrel, a fluid channel and a ventilation channel with a first channel portion extending at least substantially parallel to the fluid channel and with a second channel portion diverted towards an outside of the housing and to which an air filter element and a fluid shut-off member are assigned. A drip chamber can include a piercing part. The piercing part can be produced by an injection molding tool. The second channel portion in the housing is oriented parallel to the first channel portion and open towards an inside of the housing. An open region of the channel portion is closed by a separately produced closure part. The piercing part can be used with a medical infusion system.

Abstract: A breast pump milk flow rate sensor system and apparatus for accurately assessing both a flow rate and amount of milk expressed during a pumping session is provided. The breast pump milk flow rate sensor system and apparatus may be contained within a breast pump.

Abstract: The present disclosure relates to a flexible container for an injection device including a flexible bag having an interior volume to be filled with a liquid medicament, an outlet located at a first end of the bag, and a contraction member connected to the bag to displace a second end of the bag located opposite to the first end towards the first end.

Abstract: A system for measurement automation of a fluid injected into a patient includes a reservoir, a fluid injection apparatus, and a measurement automation apparatus. The fluid injection apparatus includes a delivery conduit, an injector for injecting the fluid into the patient, a diverter assembly disposed between the delivery conduit and the injector, and a connector between the diverter assembly and delivery conduit. The diverter assembly is configured to divert at least a portion of the fluid away from an injection fluid path between the injector and the delivery conduit to the reservoir. The measurement automation apparatus includes an injector sensor module, a reservoir sensor module, a processor configured to receive the data from the sensor modules, and a display.

Abstract: Described are embodiments that include methods and devices for separating components from multi-component fluids. Embodiments may involve use of separation vessels and movement of components into and out of separation vessels through ports. Embodiments may involve the separation of plasma from whole blood. Also described are embodiments that include methods and devices for positioning portions, e.g., loops, of disposables in medical devices. Embodiments may involve use of surfaces for automatically guiding loops to position them into a predetermined position.

Abstract: An insert for a luer-type catheter connection includes a fluid pathway connecting a female end and a male end. The male end is configured for slidable insertion into a female luer fitting of a catheter, and the female end is configured to receive a male luer nozzle of a fluid delivery device. The insert also includes a threaded collar having internal threading faced for coupling with the female luer fitting and external threading faced for coupling with a locking collar on the fluid delivery device. A cartridge located in the fluid pathway is configured to hold a patency agent and further to release the patency agent into the catheter when fluid is passed through the cartridge.

Abstract: To offload forces from a tissue site being treated with reduced pressure, an offloading pressure component may be used as part of a reduced-pressure treatment system. A reduced-pressure source of the reduced-pressure treatment system vents positive pressure exhaust into the offloading pressure component to inflate the offloading pressure component. The offloading pressure component disperses forces away from the tissue site. Other devices, methods, and systems are presented.

Abstract: A drip chamber for an infusion tube, including: a first end including a drip tube; a second end including an exit port; and a wall connecting the first and second ends and including an interior surface with a hydrophobic portion. The drip chamber includes a space enclosed by the interior wall and the first and second ends. The hydrophobic portion of the interior surface repels liquid contacting the hydrophobic coating. The hydrophobic portion of the interior surface enables light to refract through the hydrophobic portion and the wall in the same manner as is the case when the hydrophobic portion is not present on the interior surface.

Abstract: A dropping rate measuring device for measuring a flow rate of liquid droplets which grow on a lower end of a nozzle and intermittently drop from the lower end of the nozzle includes an imaging unit that images a growing liquid droplet which is growing on the lower end of the nozzle at a plurality of time points and acquires a plurality of pieces of image data of the growing liquid droplet, and a data processor that calculates the flow rate by analyzing the plurality of pieces of image data acquired by the imaging unit.

Abstract: A fluid connector includes an extending section having a spiked end to pierce a container port. The extending section includes at least one air conduit and at least one fluid conduit therethrough. The extending section further includes first and second abutment members. The first abutment member is adapted to abut a first or air side of the container port upon piercing of the container port, and the second abutment member, which is spaced from the first abutment member, is adapted to abut a second or fluid side of the container port. The fluid connector can further include grasping members extending from the extending section to facilitate rotation of the extending section relative to the container port during piercing thereof. The fluid connector can also include a check valve in fluid connection with the at least one air conduit. The check valve may be positioned within the extending section.

Abstract: A device for determining the regional distribution of a parameter for lung perfusion includes an electrical impedance tomography unit with electrodes (E1, . . . EN), which can be placed on the thorax, that are connected to a control and analysis unit (2) and an administering device (4) for the intravenous administration of a conductivity contrast medium. The control and analysis unit (2) is configured to display changes in impedance distribution occurring as a consequence of the administration of conductivity contrast medium as a parameter for lung perfusion in the section plane as a function of time. The administering device (4) has a controllable dispensing device. The control and analysis unit and the dispensing device are connected with one another via a data link (3). A start time and an end time and a quantity of an administered bolus of the conductivity contrast medium are available to the control and analysis unit (2).

Abstract: A drip chamber for an infusion tube, including: a first end including a drip tube; a second end including an exit port; and a wall connecting the first and second ends and including an interior surface with a hydrophobic portion. The drip chamber includes a space enclosed by the interior wall and the first and second ends. The hydrophobic portion of the interior surface repels liquid contacting the hydrophobic coating. The hydrophobic portion of the interior surface enables light to refract through the hydrophobic portion and the wall in the same manner as is the case when the hydrophobic portion is not present on the interior surface.

Abstract: An infusion adapter for connection with an infusion fluid container includes a connection portion including an anchor component for connecting to an injection port of the infusion fluid container, and a first port adapted for connection with a syringe assembly containing a medication fluid. The first port is in fluid communication with the connection portion. The anchor component is configured to securely connect the infusion adapter to the infusion fluid container to substantially prevent disconnection of the infusion adapter from the infusion fluid container once the infusion adapter is connected to the infusion fluid container.

Abstract: A drip chamber for an infusion tube, including: a first end including a drip tube; a second end including an exit port; and a wall connecting the first and second ends and including an interior surface with a hydrophobic portion. The drip chamber includes a space enclosed by the interior wall and the first and second ends. The hydrophobic portion of the interior surface repels liquid contacting the hydrophobic coating. The hydrophobic portion of the interior surface enables light to refract through the hydrophobic portion and the wall in the same manner as is the case when the hydrophobic portion is not present on the interior surface.

Abstract: A gravity fed infant feeding device is disclosed. The gravity feeding device may have a cover with a through hole that allows liquid nutrients within the infant feeding device to be fed to an infant by way of gravity. If the infant feeding device clogs up, then either an integrated pump or a separate pump may be applied to the infant feeding device to increase pressure and push out the clog from the system. the through hole may be covered with a hydrophobic filter to allow air to pass there through and allow the feeding of the infant by way of gravity yet liquid nutrients within the infant feeding device cannot escape or be contaminated during use.

Abstract: A kit comprising a medical dispensing container (402), such as a vial for diagnostic agents, and a liquid transfer device (401) to be used to transfer a liquid into or from said dispensing container. The transfer device allows substantially limiting the gaseous exchange between the inside of a vial and the external ambient, when the device is connected to the vial in steady state conditions.

Abstract: An improved safety occluder and method of use provides an occluder for an infusion set having a first, occluding position, a second, non-occluding position which returns to the first, occluding position when the occluder's plunger is released, and a third, non-occluding position which retains the plunger in a configuration which allows fluid flow through the infusion set. The occluder may also include a locking mechanism to prevent accidental movement of the plunger out of the first, occluding position.

Abstract: The invention relates to a drip chamber for an infusion device and an infusion device having such a drip chamber, by means of which medical solutions can be fed to a patient, such as infusion solutions for chemotherapy. The drip chamber (1) according to the invention is provided for connecting to a fastener (8) of an infusion container (2), comprising a withdrawal part (25) for withdrawing fluid, having an opening (28) closed by a penetrable membrane (27) and an injection part (26) for injecting a fluid, having an opening (30) closed by a penetrable membrane (29). The connecting part (7) and/or piercing spike (11) of the drip chamber (1) according to the invention is designed such that a snap-fit or latching connection to the injection part (13) and/or the withdrawing part (25) of the fastener (8) of the infusion container (2) can be produced when the connecting part (7) of the drip chamber (1) is connected to the fastener (8) of the infusion container (2).

Abstract: Some embodiments of an infusion pump system may include an occlusion sensor that can be used to detect when an occlusion exists in the fluid path between the medicine reservoir and the infusion site on the user's skin. Such an occlusion may occur, for example, when the fluid flow line (e.g., a cannula, infusion set tubing, or the like) is kinked. If the medicine dispensation path to the user is occluded, the user may receive no dosage or a lower dosage of the medicine. As such, the occlusion sensor can be used to indicate when the fluid is flowing or not flowing, thereby permitting the infusion pump system to communicate an alarm to the user if an occlusion exists.

Abstract: A drip chamber for an infusion tube, including: a first end including a drip tube; a second end including an exit port; and a wall connecting the first and second ends and including an interior surface with a hydrophobic portion. The drip chamber includes a space enclosed by the interior wall and the first and second ends. The hydrophobic portion of the interior surface repels liquid contacting the hydrophobic coating. The hydrophobic portion of the interior surface enables light to refract through the hydrophobic portion and the wall in the same manner as is the case when the hydrophobic portion is not present on the interior surface.

Abstract: The fluid injector system includes a source of injection fluid, a pump device, and a fluid path set in fluid connection with the source of injection fluid and the pump device. The fluid path set includes a drip chamber including an elongated body having a raised projection from substantially a top end to substantially a bottom end, the elongated body configured to receive and contain the injection fluid. A fluid level sensing mechanism is operably associated with a fluid control device, and includes a support for the drip chamber body, wherein the support is adapted such that the raised projection is in operational contact with a fluid level sensor associated with the support. The fluid level sensing mechanism is operable to transmit ultrasonic or light energy through the raised projection to be sensed by the fluid level sensor for sensing the injection fluid level in the drip chamber.

Abstract: Detection of fluid conditions in an administration set. A light source is positioned to transmit an infrared light through administration set tubing and any fluid therein. A light sensor senses the infrared light transmitted through the tubing and generates an output signal. A frequency of the output signal is a function of an intensity of the light transmitted through the tubing. A processor receives and determines the frequency of the output signal, and compares the determined frequency to threshold frequency values to determine whether fluid is in the tubing. The processor also monitors the generated output signal to determine if the frequency of the output signal changes over time, and determines whether fluid is flowing in the tubing as a function of the determined change in frequency.

Abstract: Disclosed is an infusion flow regulator, in which a reference point is set within a manipulating range of a manipulation unit for regulating a flow rate in the infusion flow regulator, so that a manipulating point of the manipulation unit can be tuned with reference to the ratio of a flow rate measured at the reference point in relation to a prescribed injection flow rate, whereby the flow rate can be quickly and accurately tuned to the prescribed flow rate. The disclosure also includes an infusion flow regulating set including the infusion flow regulator, and an infusion flow regulating method using the same.

Abstract: The present disclosure provides for an airless intravenous (IV) bag which contains a specialized device, referred to herein as the airless intravasculature infusion device (AIVID). The AIVID allows one to view the amount of fluid in the IV bag but substantially decreases or completely prohibits the risk of an inadvertent air infusion into a patient.

Abstract: There is provided a combination of a portable monitoring device for monitoring a portable drip infusion set for use in hospitals and the like and the portable drip infusion set, preferably being of the type comprising a liquid supply, a drip chamber downstream of the liquid supply for forming liquid drops and a flexible tube connecting the drip chamber with an injection needle.

Abstract: An infusion pump, including: a microprocessor; a drip chamber; a drip tube with an end in the drip chamber; and an illumination system: with a light source for transmitting light through the drip chamber to a drop of fluid suspended from the drip tube; and for controlling illumination properties of the light transmitted to the drop. The pump includes an optical system for: receiving light transmitted through the drop; and transmitting, to the microprocessor, data regarding the received light. The microprocessor: generates, using the data, an image of the drop; locates, using the image, an outer edge of the drop to define a boundary of the drop; integrates an area enclosed by the boundary; and calculates a volume of revolution for the drop with respect to an axis for the drop that intersects the end of the drip tube, assuming symmetry of the drop with respect to the axis.

Abstract: Disclosed is an infusion port for regulating the inflow of an aqueous solution of an aqueous-solution pack into an external ringer spike as at least part of the ringer spike is inserted or withdrawn. The infusion port comprises an inflow part, a securing part, and a cover part. The inflow part is formed with at least one first inflow hole into which the ringer spike is inserted, so as to allow the inflow of the aqueous solution of the aqueous-solution pack as the ringer spike is inserted. Consequently, as the first inflow hole of the inflow part moves outside or inside the securing part, it is possible to regulate the flow of the aqueous solution of the aqueous-solution pack through the first inflow hole and into the ringer spike disposed inside the inflow part.

Abstract: A dual pump irrigation/aspiration pump system capable of operating in a plurality of different modes suitable for a variety of different endoscopic surgical procedures. The system monitors actual or calculated intra-articular pressure and adjusts flow to maintain surgeon requested pressure at the surgical site while controlling outflow. The irrigation/aspiration pump system has an inflow pump and tubing dedicated to communicating fluid to the surgical work site and an outflow pump and tubing dedicated to removing fluid from the work site at a controlled rate. The system further has different size inflow and outflow pumps and tubing cassettes, means for altering the outflow fluid flow rate to accommodate a surgical tool and a means for declogging the surgical tool in the event of blockage. In a preferred embodiment a pressure control system provides inferred pressure information representative of the pressure at the work site.

Abstract: A regulating device for an intravenous drip set comprising a main housing unit (1) which comprises a mobile roller (2) which can gradually compress a flexible tubing (4) until the tubing (4) is fully compressed and a fixed roller (3) which together with the mobile roller (2) squeeze the flexible tubing of an intravenous line into a totally closed position to act as a flusher for the intravenous line, whereby when by sliding the entire device downwards along the tubing (4) proximally towards a patient, flushing of fluid in the intravenous line is thereby achieved.

Abstract: A pump set for use in a liquid delivery pump of the type for delivering liquid to a patient, having an infrared radiation detector for detecting infrared radiation, and providing an indication that the pump set is properly loaded on the pump. The pump set comprises a conduit for the liquid and a safety interlock member which is carried by the conduit. The safety interlock member is formed of a material that transmits infrared radiation and blocks visible light.

Abstract: An intravenous system includes an assembly for coupling a solution container to a delivery system drip chamber used for regulating the flow rate of solution in a patient intravenous line. In one embodiment, the solution delivery system includes a drip chamber having an opening formed in a side wall, and a vent plug disposed in the opening for providing a self-priming function to the IV system. A termination end of the patient intravenous line includes an end cap with a vent and a seal for allowing air in the intravenous line to escape through the end cap while preventing leakage of solution from the termination end.

Abstract: A flow control system includes a drip chamber having lower and upper wall sections and a collapsible wall extending between the lower and upper wall sections, a downwardly depending valve seat attached to the lower wall section, and a valve member disposed in the drip chamber, attached to the upper wall section and having a valve surface engageable with the valve seat. The system also includes a driver rotatably engaged to the lower and upper wall sections. Upon rotation of the driver in a first direction, the collapsible wall of the drip chamber moves between a collapsed condition in which the valve seat is sealingly engaged with the valve surface and an extended condition in which the valve seat is sufficiently spaced from the valve surface to form a flow passageway between the valve surface and the valve seat and permit flow through the opening of the drip chamber.

Abstract: A fluid dispensing device includes a pressurizing device coupled between a fluid bottle and a discharge tube for forcing the fluid to flow through the discharge tube without gravity, the pressurizing device includes a container having an inclined inner peripheral surface, and a piston slidably received in the container and having an outer peripheral portion for selectively engaging with the inclined inner peripheral surface of the container in order to pump the fluid into the discharge tube when the piston is moved toward the discharge tube with a coil, and for being selectively disengaged from the inner peripheral surface of the container when the piston is moved away from the discharge tube.

Abstract: A system to minimize fluid turbulence inside a tissue cavity during endoscopic procedures. A body tissue cavity of a subject is distended by continuous flow irrigation using a solenoid operated pump on the inflow side and a positive displacement pump, such as a peristaltic pump, on the outflow side, such that the amplitude of the pressure pulsations created by the outflow positive displacement pump inside the said tissue cavity is substantially dampened to almost negligible levels. The present invention also provides a method for accurately determining the rate of fluid loss into the subject's body system during any endoscopic procedure without utilizing any deficit weight or fluid volume calculation, the same being accomplished by using two fluid flow rate sensors. The present invention also provides a system of creating and maintaining any desired pressure in a body tissue cavity for any desired cavity outflow rate.

Abstract: The present invention refers to a tubing set (12) suitable for use in co-operation with a hemodialysis machine (10). The tubing set comprises: an out-tube (14) for supplying the blood from the patient to a filter (16) of the machine; an in-tube (18) for supplying the blood from the filter back to the patient; a drip chamber (20) placed along one of said tubes, adapted to let the blood drip through an air buffer (22); and a vial gate (24) for the connection of vials (26) containing drugs to be delivered into the blood. The vial gate (24) according to the invention comprises a delivery lumen (28), suitable for delivering the drug (30) from the vial to the drip chamber, and a vent lumen (32), suitable for providing air (34) inside the vial in order to replace the delivered drug.

Abstract: A bubble free, self-priming IV set for use in the administration of liquids includes a coupling assembly for attaching the delivery system to a source of liquid and includes a coupling membrane for controlling the flow of liquid and air through the coupling assembly. The system also includes a drip chamber for receiving liquid through the coupling assembly, the drip chamber having a membrane for preventing air from leaving the drip chamber. A self leveling port is disposed within a wall of the drip chamber, the port being permeable to air, but impermeable to liquid. Finally, a patient conduit is in fluid communication with the drip chamber and further comprises a flow control plug disposed at the distal end of the conduit. The flow control plug is permeable to air but impermeable to liquid. Use of this system allows a clinician to attach a source of fluid to a patient without significant intervention, while the system self primes.

Abstract: The fluid injector system includes a source of injection fluid, a pump device, a fluid control device operably associated with the pump device, and a fluid path set in fluid connection with the source of injection fluid and the pump device. The fluid path set includes a drip chamber including an elongated body having a top end, a bottom end and a raised projection, the raised projection being substantially rectangular in shape and extending longitudinally from the top end along the drip chamber body and terminating adjacent to the bottom end. A fluid level sensing mechanism is operably associated with the fluid control device, and includes a drip chamber support for supporting the drip chamber body and a fluid level sensor associated with the drip chamber support.

Abstract: A pump set for use in a liquid delivery pump of the type for delivering liquid to a patient, having an infrared radiation detector for detecting infrared radiation, and providing an indication that the pump set is properly loaded on the pump. The pump set comprises a conduit for the liquid and a safety interlock member which is carried by the conduit. The safety interlock member is formed of a material that transmits infrared radiation and blocks visible light.

Abstract: There is provided a combination of a portable monitoring device for monitoring a portable drip infusion set for use in hospitals and the like and said portable drip infusion set, preferably being of the type comprising a liquid supply, a drip chamber downstream of said liquid supply for forming liquid drops and a flexible tube connecting said drip chamber with an injection needle.

Abstract: The present invention describes IV regulators that allow interruption of normal controlled-flow for a safe and convenient bolus flush, either for a specific period of time or for a specific volume of saline flush. Two time-controlled IV regulators are shown, one employing a pneumatic cylinder counter-opposed by elastic band(s) for administering a bolus flush, and one employing a compressible lever and torsion spring counter-opposed by a rotary damper. In both cases the mechanisms disengage the roller-clamp from the IV tube for a predetermined amount of time to fully open fluid flow there through for a bolus flush before return to the regulated-flow position. The volume-controlled flow regulator employs two internal bladders and allows one bladder to fill while the other bladder drains (and vice versa) by flipping a slider paddle-type toggle, thus enabling the administration of a set volume of flush fluid.

Abstract: A flow control system includes a drip chamber having lower and upper wall sections and a collapsible wall extending between the lower and upper wall sections, a downwardly depending valve seat attached to the lower wall section, and a valve member disposed in the drip chamber, attached to the upper wall section and having a valve surface engageable with the valve seat. The system also includes a driver rotatably engaged to the lower and upper wall sections. Upon rotation of the driver in a first direction, the collapsible wall of the drip chamber moves between a collapsed condition in which the valve seat is sealingly engaged with the valve surface and an extended condition in which the valve seat is sufficiently spaced from the valve surface to form a flow passageway between the valve surface and the valve seat and permit flow through the opening of the drip chamber.

Abstract: A portable drip structure comprises an inflating structure and a main bag. The inflating structure includes a motor and an air container and the motor and the air container are communicative with each other via a pipe provided there between, so that the air container can be inflated by the inflating structure. The main bag is provided with a first and a second compartment that neighbor with each other and each compartment is provided on the main bag with an opening that can be enclosed. The first compartment is for disposing a drip bag while the second compartment is for disposing the inflating structure. Consequently, when the two openings are enclosed and the air container is inflated via the motor, the air container will be expanded to press the drip bag in the first compartment to drip the infusion liquid in the drip bag outward.

Abstract: A bubble free, self-priming IV set for use in the administration of liquids that includes a drip chamber comprising a chamber inlet and a chamber outlet, a bubble isolation device disposed within the drip chamber that prevents air bubbles from exiting the chamber outlet, a tube having an inlet end coupled to the chamber outlet of the drip chamber and an outlet end, and an end plug that includes an air vent. The end plug may be coupled to the outlet end of the tube and is a flow restrictor so that when a liquid is moving through the tube, the velocity of the liquid flow is controlled such that the front of the liquid does not trap bubbles in the tube.

Abstract: The application relates to a drip chamber (1) for an infusion device, to an infusion device with a drip chamber, and to an arrangement composed of an infusion container (16) and of such an infusion device. The drip chamber (1) of the infusion device has a securing part (11) for securing the drip chamber releasably to the infusion container. The securing part (11) of the drip chamber has a plurality of securing elements (12) which are arranged along the circumference of a circle and which, on the inner sides facing each other, have grooves (12A) extending along the circumference of a circle. The securing elements are designed in such a way that they can be spread from a position in which they engage firmly around the connector part of the infusion container to a position in which they release the connector part of the infusion device. The securing elements (12) secure the piercing spike (10) of the drip chamber against slipping out of the piercing part (23) of the connector part (20) of the infusion container.

Abstract: An apparatus regulates fluid flow supplied to a patient through an intravenous infusion system. The apparatus includes a first fluid passageway, a second fluid passageway, an inlet, and a control device. The first fluid passageway is for discharging fluid therefrom at a first predetermined rate of flow. The second fluid passageway is for discharging fluid therefrom at a second predetermined rate of flow, wherein the second predetermined rate of flow is different than the first predetermined rate of flow. The inlet is in flow communication with the first and second fluid passageways. The control device is between the inlet and the first and second fluid passageways, and is variably positionable for controlling fluid flow into the first and second fluid passageways.

Abstract: The present invention is related to a liquid blocking apparatus and a system thereof, wherein if the liquid contained in an IV bag or a liquid tank is oozed out completely, the flow of liquid is blocked, the alarm lamp is turned on, the alarm sound is generated, and then the supply of liquid is maintained for a predetermined time.

Abstract: A regulating device for an intravenous drip set comprising of a main housing unit (1) which comprises of a mobile roller (2) which can gradually compress the flexible tubing (4) until the tube (4) is fully compressed and a fixed roller (3) which together with the mobile roller (2) squeeze the flexible tubing of the intravenous line (4) into a totally closed position to act as a flusher for the intravenous line (4), whereby when by sliding the entire unit downwards along the tubing (4) proximally towards the patient, the flushing of the fluid in the intravenous line (4) is thereby achieved.

Abstract: A fluid dispensing device includes a pressurizing device coupled between a fluid bottle and a discharge tube for forcing the fluid to flow through the discharge tube without gravity, the pressurizing device includes a container having an inclined inner peripheral surface, and a piston slidably received in the container and having an outer peripheral portion for selectively engaging with the inclined inner peripheral surface of the container in order to pump the fluid into the discharge tube when the piston is moved toward the discharge tube, and for being selectively disengaged from the inner peripheral surface of the container when the piston is moved away from the discharge tube.