301 results about "Stopped flow" patented technology

This invention relates to a novel microfluidic device and methods of using this device to conduct in vitro studies on the reaction and effects of various compounds on cells. More particularly, it relates to a method for using stop flow in a microfluidic system to study the effect of compounds on individual cells. It also provides a method for observing the effects of candidate compounds on leukocyte rolling.

The fluid delivery system generally includes a source of injection fluid, a pump device a fluid path set disposed between the source of injection fluid and the pump device, and a fluid control device. The fluid path set includes a multi-position valve. The fluid control device is operatively associated with the fluid path set and includes a valve actuator adapted to operate the multi-position valve. The valve actuator is adapted to close the multi-position valve to isolate the pump device from a patient and stop flow of the injection fluid to the patient at substantially any pressure or flow rate generated by the pump device for delivering a sharp bolus of the injection fluid to the patient. The valve actuator is generally adapted to selectively place the pump device in fluid communication with the source of injection fluid for supplying the injection fluid to the pump device and the patient.

The fluid delivery system generally includes a source of injection fluid, a pump device a fluid path set disposed between the source of injection fluid and the pump device, and a fluid control device. The fluid path set includes a multi-position valve. The fluid control device is operatively associated with the fluid path set and includes a valve actuator adapted to operate the multi-position valve. The valve actuator is adapted to close the multi-position valve to isolate the pump device from a patient and stop flow of the injection fluid to the patient at substantially any pressure or flow rate generated by the pump device for delivering a sharp bolus of the injection fluid to the patient. The valve actuator is generally adapted to selectively place the pump device in fluid communication with the source of injection fluid for supplying the injection fluid to the pump device and the patient.

An automatic stop valve formed in a container of a medical fluid administration system includes an electrical field that attracts the float and valve seat together to shut off flow from the exit port of the container when the fluid within the container is reduced to a predetermined level. One or both of the float and valve seat creates an electric field that attracts the other, which is made of a non-magnetic dielectric, into engagement. In one embodiment, the valve seat is formed of an electret that creates the electric field attracting the float to it to stop flow. In another embodiment, the float comprises an electret that attracts the float to the dielectric valve seat. In yet another embodiment, both the float and valve seat include electrets of opposite polarity that attract each other into engagement. The lack of magnetic and metallic materials makes the shut off valve suitable for use in an MRI environment.

Stop flow interference lithography system for high throughput synthesis of 3-dimensionally patterned polymer particles. The system includes a microfluidic channel containing a stationary oligomer film and a phase mask located adjacent to the microfluidic channel. A source of collimated light is provided for passing the collimated light through the phase mask and into the microfluidic channel for interaction with the oligomer. The passage of the collimated light through the phase mask generates a 3-dimensional distribution of light intensity to induce crosslinking of the oligomer in high intensity regions thereby forming 3-dimensional structures.

Systems and methods for sealing and venting a septum of an intravenous catheter device. Implementations of the present invention include a compact, molded septum that is retained within an inner lumen of a catheter adapter such that slowed or stopped flow of air and / or a fluid is permitted to pass between the compact septum and an inner wall surface of the catheter adapter via one or more fluid pathways. In some instances, a snap ring is provided to secure the position of the compact septum within the catheter adapter, a fluid pathway being provided through the snap ring.

Methods and fuel systems to reduce evaporative emissions of a volatile fuel. A fuel tank contains fuel, a carburetor mixes air with the fuel from the fuel tank, and a plurality of fluid paths route fuel amongst and / or between the fuel tank and the carburetor. A valve actuation device stops flow of fuel in one or more of the plurality of fluid paths and the carburetor is adapted to be drained of fuel during engine shutdown to reduce or prevent evaporative emissions from the fuel system. The carburetor is preferably designed so as to minimize a volume of fuel contained therein.

A bodily fluid analyzer including a test strip holder comprising a base and a snap-on cover which completely enclose the test strip except for a sample port in the cover and a sensor port in the base. The test strip is compressed between the base and cover in a sample container having a well-defined sample volume. The test strip comprises a woven dispersement layer, a depth filter containing a reagent, an asymmetrical membrane containing additional reagent, and a colorimetric detection membrane in a vertical stack. The red blood cells are removed from the colorimetric detection area by slowing their vertical movement and stopping flow when the detection membrane is saturated. A minimum value of the reflectance in a color range is used to determine a characteristic of the bodily fluid.

The invention relates to a disposable centrifugal type plasma separator; a hemostix, a plasma filter pipeline, a separation cup and a blood storage bag are connected to form a transport channel in sequence; the hemostix comprises a blood taking needle and a catheter which is connected with the blood taking needle; the catheter is provided with a stop flow clip; the plasma filter pipeline comprises a puncture outfit, a blood filter and an air filter; the inputs of the puncture outfit and the blood filter are respectively connected with a tee interface by the catheter; the other end of the tee interface is connected with the catheter in the hemostix; the air filter is connected with one output of the blood filter by the catheter while the other output of the blood filter is connected with the input of the separation cup by the catheter; and the output of the separation cup is connected with the blood storage bag by the catheter. The invention has the advantages that as the disposable plasma collection consumables which are singly packaged originally are assembled, packaged and sterilized in the same purified environment, the risk of sterility connection for the parts is greatly reduced, and the workload of medical personnel is decreased, too.

Methods and fuel systems to reduce evaporative emissions of a volatile fuel. A fuel tank contains fuel, a carburetor mixes air with the fuel from the fuel tank, and a plurality of fluid paths route fuel amongst and / or between the fuel tank and the carburetor. A valve actuation device stops flow of fuel in one or more of the plurality of fluid paths and the carburetor is adapted to be drained of fuel during engine shutdown to reduce or prevent evaporative emissions from the fuel system. The carburetor is preferably designed so as to minimize a volume of fuel contained therein.

A test strip and method for detecting an analyte present in a sample. The test strip comprising: a buffer addition zone to which a buffer may be added; an absorbent zone proximal to the buffer addition zone; one or more test zones distal to the buffer addition zone, at least one of the test zones including a first analyte binding agent immobilized therein which is capable of binding to the analyte to be detected; a terminal buffer flow zone distal to the one or more test zones, the absorbent zone being positioned relative to the buffer addition zone and having an absorption capacity relative to the other zones of the test strip such that when a volume of buffer within a predetermined buffer volume range for the test strip is added to the buffer addition zone, a distal diffusion front of the buffer diffuses from the buffer addition zone to a distal diffusion point within the terminal buffer flow zone and then diffuses proximal relative to the one or more test zones; and a sample addition zone distal to the terminal buffer flow zone to which a sample may be added.

The invention relates to the field of ecological environment protection, in particular to a method used for afforesting a desert. The method used for afforesting the desert comprises the following steps of: 1, excavating a filling slot; 2, paving a waterproof impervious layer; 3, paving a sand layer; 4, paving a plant growing layer; and 5, paving a straw plaited grid. The waterproof impervious layer is arranged in the sand layer, the waterproof impervious layer stops flow direction of water, and water can not leak everywhere deep in the sand layer, thus the aim of saving water is achieved; the used material is environmentally friendly, and human and natural environment can not be polluted; water supply is reasonable, water can be uniformly supplied to plants used for afforesting, the plants can rapidly grow, and the problems of water for afforesting the desert and rainwater seepage control can be effectively solved. The method has a wide application field and is convenient for standardization construction. By applying the method to afforest the desert, a conditioned desert can be afforested, desert vegetation coverage rate can be improved, and a local ecological environment of the desert can be improved.

A scanning method for scanning samples of biological cells using optical tomography includes preparing, acquiring, reconstructing and viewing three-dimensional images of cell samples. Concentration and enrichment of the cell sample follows. The cell sample is stained. Cells are isolated from the cell sample and purified. A cell / solvent mixture is injected into a gel by centrifugation. A cell / gel mixture is injected into a capillary tube until a cell appears centered in a field of view using a stopped-flow method. An optical imaging system, such as a fixed or variable motion optical tomography system acquires a projection image. The sample is rotated about a tube axis to generate additional projections. Once image acquisition is completed, the acquired image projections are corrected for errors. A computer or other equivalent processor is used to compute filtered backprojection information for 3D reconstruction.

A microfluidic system and method, suitable for "lab-on-a-chip" applications, by which a bubble is inflated in fluid flowing through a microfluidic channel at a predetermined location along the channel and the bubble is maintained at that location to stop flow through the channel in the manner of a valve. The microfluidic channel is formed on a semiconductor chip and a pair of electrodes is formed one on each side of the channel, whereby a bubble is electrochemically inflated between the electrodes and held in fixed position by the channel wall when a voltage is applied across the fluid incident to connecting the electrodes to a voltage source. When the voltage is removed, deflation of the bubble valve rapidly occurs to restore flow. The present invention provides flow control in a microfluidic system regardless of channel cross-sectional geometry and with no moving parts and low power consumption. Moreover, the present invention may be practiced using existing fabrication techniques.

An inflatable cuff for blood pressure measurement includes a first inflatable bag which is inflatable to press an arterial vessel of a body portion of a living subject and stop flow of blood in the arterial vessel which the inflatable cuff is adapted to be wound around the body portion; a second inflatable bag for sensing a pulse wave propagating along the arterial vessel, which is supported by the inflatable cuff such that the second inflatable bag is located inside a downstream-side portion of the first inflatable bag in the direction of the blood flows in the arterial vessel, and which has a dimension as measured in the direction that is smaller than a dimension of the first inflatable bag as measured in said direction; and a fluid-filled bag which is located between the second inflatable bag and the body portion and which is filled with incompressible fluid.

The invention discloses a multi-taste beverage distributing spray nozzle and an distributor using the same, wherein the distributing spray nozzle comprises at least one water inlet, at least two thick juice inlets, a main water flowing path penetrating the spay nozzle and at least two thick juice flowing paths penetrating through the spray nozzles, wherein the thick juice flowing paths are communicated with each thick juice inlet through fluid and are respectively stopped at thick juice discharge openings. By using the water flowing paths, water is sprayed from the spray nozzle in a curtain shape and is preferably annular; the thick juice discharge opening comprises a thick juice deflector by which the thick juice is dispersed in a sector shape to impact a water curtain when flowing out of the discharge opening. The spray nozzle comprises at least two auxiliary water flowing paths by which water transfers from the main water flowing path and the transferred water penetrates through at least two thick juice discharge openings for discharging. On the downstream, the spray nozzle comprises a convex surface and water is gathered around the convex surface when stopping flowing. The beverage distributor uses a plurality of multi-taste beverage distributing spray nozzles. The distributor also comprises distributing spray nozzles for distributing a taste addictive; and the distributing spray nozzles can be used for distributing ice; even the distributor is provided with an ice crusher, thereby distributing crushed ice or block ice.

The invention discloses a flow detection method, a flow detection device and a water purification device. The flow detection method is applied to flow meters and is characterized by including the steps: detecting pulse widths of pulse signals sent by a sensor of the flow meter by a set time interval; calculating subtotal flow rates within the time interval according to the pulse widths; obtaining a total flow rate by summing up the subtotal flow rates from the time when liquid passes through the flow meter to the time when the liquid stops flowing through the flow meter. By adoption of the flow detection method, detection speed can be increased while detection precision can be improved.