An improved rapid diagnostic device, assay and multifunctional buffer reagent are provided for the detection of a target analyte in a fluid test sample. The 2-step assay utilizes a dual component flow-through device comprising a test unit and a dried indicator reagent delivery unit capable of receiving the fluid sample and multifunctional buffer, respectively. The test unit comprises a reaction zone containing immobilized capture reagent that can specifically bind to the target analyte, an absorbent zone supporting the reaction zone, and optionally, a blood separation zone in lateral fluid communication with the reaction zone. The dried indicator reagent delivery unit comprises a label zone permeated with a dried indicator reagent which is capable of being placed in transient fluid communication with the reaction zone of the test unit during the assay procedure. The rapid diagnostic assay system reduces the number of assay reagents, method steps and time required for performance compared to other conventional assays.

Diagnostic assays have become an indispensable aid in medical and research fields for detecting a variety of components in biological fluids and tissue samples such as drugs, hormones, enzymes, proteins, antibodies, and infectious agents. A fundamental principle underlying the operation of a number of these assays is a specific recognition and binding reaction that occurs between two or more members to form a complex that can subsequently be detected. Normally, the members involve a capture reagent (e.g. receptor) that will specifically recognize and bind to a target analyte of interest (e.g. ligand) in a fluid test sample (e.g. whole blood, plasma, serum, urine, saliva, etc.). Moreover, a visually detectable indicator reagent is included in the reaction which will recognize and bind to any analyte complexed with the capture reagent to produce a signal indicating that a positive reaction has occurred. In particular, immunological assays are designed to function on the basis of antibody recognition and selective binding reaction to antigen and accordingly, have proven extremely valuable over the years in clinical applications for the detection of numerous infectious disease states.
In order to achieve accurate results, however, immunoassays often require precision in performing a series of time-consuming steps, as well as technical knowledge in operating sophisticated laboratory equipment. Accordingly, their use in diagnosing infectious disease has been essentially confined to clinical facilities that have the necessary resources for making such determinations including highly trained technical personnel and laboratories equipped with appropriate diagnostic equipment.
On this basis, as with many technologies, immunodiagnostic testing is evolving towards more simplistic approaches in the rapid identification and diagnosis of infectious disease states. The need for a simplistic qualitative assay for detecting analyte in a biological sample is becoming more desirable since it would offer an appealing possibility for use in less conventional settings having limited resources, e.g. physician's office, or domestic household. Whether in a public health clinic or a rural setting, it is preferable that an assay for detection of a target analyte in a fluid test sample be performed without the aid of complicated instruments and the requisite skills and knowledge of professionally trained personnel.
Another important factor to consider in pursuit of improved diagnostic testing is the lack of, or limited availability of, freezers and refrigeration in many third world countries. On this basis, it has become more desirable to develop assay reagents that will maintain their stability and integrity at room temperature for prolonged periods of time. Presently, some diagnostic devices and methods require the use of several assay reagents which have varying stability depending on the temperature at which they are stored and handled. Some of these reagents are stable at room temperature and may be stored for short periods of time, while others are relatively unstable and begin to deteriorate quickly, thereby adversely affecting the overall sensitivity and reliability of the assay. Thus, most commercially available diagnostic devices require at least one or more of the necessary reagents be kept at low temperatures in order to ensure their stability. Accordingly, a diagnostic device incorporating reagents that can be stored at ambient temperatures and remain stable for long periods of time while retaining all, or most, of its initial activity would have a clear advantage over current state of the art devices. On this basis, a factor worth considering towards simplifying diagnostic testing and thus, making it more practical and widely operational, is to minimize the number of assay reagents (e.g. mixing, washing, diluting solvents, etc.) and integrated steps in the assay protocol.
An immunodiagnostic assay which is simple to use, rapid and reliable would also be advantageous in improving screening and diagnostic services. According to the U.S. Center for Disease Control and Prevention report, rapid diagnostic tests enable healthcare providers to supply within minutes the test results to patients at the time of testing, thus potentially increasing the overall effectiveness of counseling and testing programs. It would also be expected that simplification of diagnostic devices and assays would likely be less costly to manufacture and perform compared to other conventional devices, thus making them economically feasible and more affordable to use in the interim. This is particularly desirable in third world countries where a simple, rapid, sensitive, and economical diagnostic device and assay would be ideal.
Towards this end, numerous analytical devices in an wide assortment of shapes, configurations and formats have been developed for detecting the presence of a target analyte in a fluid test sample, including chromatographic test strips, dipsticks, lateral flow and flow-through systems, to name a few. Many of these devices employ reaction membranes onto which a capture reagent capable of recognizing and binding to the target analyte is immobilized. In essence, the method of performing the assay typically involves applying a fluid test sample suspected of containing the target analyte, either directly or indirectly by filtration, to the reaction membrane. If the target analyte is present in the sample, it will bind to the capture reagent. Subsequent methods are then employed to determine whether the target analyte has bound to the capture reagent, thus indicating its presence in the sample.
U.S. Pat. No. 4,517,288 (Giegel, et al.) discloses methods for conducting ligand-binding assays using inert porous materials. In particular, the patent discloses immobilizing an immunological binding material (e.g. antibody) specific for the ligand of interest (e.g. antigen) within a finite test zone of the porous material and applying the ligand to the test zone, which will be captured by the immobilized binding material. Immobilization of the binding material to the porous material may be achieved by any number of conventional methods including adsorption, covalent bonding, use of a coupling agent, etc. An enzyme-labeled indicator reagent, which will also recognize and bind with the ligand, is then applied to the test zone where it will become immobilized in an amount directly proportional to that of ligand present in the zone. A solvent is then applied to the center of the test zone to remove any unbound indicator reagent, thus enabling the determination of a signal to be made, with or without the aid of appropriate analytical instruments.
A more sophisticated version of a specific binding assay is described in U.S. Pat. Nos. 4,094,647, 4,235,601 and 4,361,537 (Deutsch, et al.), which incorporates a chromatographic test strip capable of transporting a developing liquid by capillary action. The test strip is designed so that it has a first zone for receiving a sample, a second zone impregnated with a first reagent capable of being transported by the developing liquid and a third zone impregnated with a third reagent. In addition, the device comprises a measuring zone and a retarding element which may be either the second reagent or the material of the strip. The first reagent is capable of reacting with one of the group consisting of (1) the sample, (2) the sample and the second reagent, or (3) the second reagent in competition with the sample, to form a product in an amount dependent on the characteristic being determined. A sample is contacted with the first zone and the strip is then dipped into the developing liquid to bring about transport of the sample and the first reagent to form the reaction product. The retarding element slows transport of either the product or the first reagent (the moving reagent) to spatially separate the two and the amount of the moving element is then measured at the measurement location.
A variation of the device by Deutsch, et al. is described in U.S. Pat. No. 4,960,691 (Gordon et al.) for the analysis of antigens, antibodies or polynucleotides, which also uses a length of a chromatographic material (i.e. test strip), a solvent carrier and mobile reagents. Essentially, the strip has three separate zones comprising a first zone impregnated with a mobile reagent reactive with the analyte of interest, a second zone for receiving a test sample suspected of containing the analyte, and a third zone impregnated with an immobilized reagent which selectively binds to the analyte, thereby rendering the analyte in an immobilized form. Each zone is sequentially located an equidistant from its neighbour along a longitudinal axis of the test strip. The device optionally comprises fourth and fifth zones impregnated with indicator reagents that will provide a means of detecting the presence of the analyte. The method involves depositing the test sample in the second zone, followed by solvent addition to the strip at the end where the first zone is located so that sequential movement and arrival of the analyte and first reagent eventually occurs at the third zone. The site relationship between the second and third zones is such that the analyte is immobilized against solvent transport at the third zone prior to the first reagent reaching the third zone. Any interfering non-analyte sample components, which are reactive with the first reagent, are cleared from the third zone by solvent transport prior to the arrival of the first reagent to the third zone. Multiple and single pathway devices are also disclosed for accomplishing a variety of multi-step assay procedures.
U.S. Pat. No. 4,168,146 (Grubb, et al.) discloses the use of test strips for carrying out sandwich-type immunoassays. The strips are formed of bibulous carrier materials to which antibodies have been attached by adsorption, absorption or covalent bonding. Preferred test strip materials include cellulose fibre-containing materials such as filter paper, ion exchange paper and chromatographic paper. Also disclosed are uses of materials such as cellulose thin-layer chromatography discs, cellulose acetate discs, starch and three-dimensional cross-linked materials such as Sephadex (Pharmacia Fine Chemicals, Uppsala Sweden). The immunoassay is performed by wetting the test strip with a measured volume of a test sample suspected of containing the antigen. Any antigen present in the test sample migrates by capillary action along the test strip. However, the extent of migration of the antigen over a fixed time period is determined by the antigen concentration in the test sample because the bound antibodies retard the migration of the antigens for which they are specific. Afterwards, the antigen-containing areas of the diagnostic device are indicated by the addition of labeled antibodies.
An immunodiagnostic flow-through system comprising a series of method steps is disclosed in U.S. Pat. No. 4,632,901 (Valkirs, et al.). The first step involves taking a fluid test sample suspected of containing a first member of a specific binding pair (e.g. antigen) and pouring it onto a porous material to which a second member of the specific binding pair (e.g. antibody) is immobilized. Influenced by the capillary action properties of an absorbent material, the fluid test sample is drawn downwards in a vertical direction through the porous material and pass the immobilized antibody. Any antigen present in the sample will subsequently be captured by the immobilized antibody. The second step involves passing a separate solution of labeled antibody through the porous material so that the labeled antibody may bind to the antigen already captured by the immobilized antibody to form a three-membered complex. Any unreacted or unbound labeled antibody is then flushed away from the porous material via a third step, normally referred to as a washing step, using a suitable reagent which may then be followed by an incubation period. Finally, a fourth step involving a separate solution containing a substrate reactive with the label on the antibody of the second solution is added to cause a visible color change indicative of the presence of the antigen of interest. To facilitate accurate performance of this method, the apparatus is designed in such a way as to funnel the sample through to the absorbent material which, by capillary action, draws the sample through the material and into the bottom of the apparatus.
An immunodiagnostic flow-through system described by Liotta in U.S. Pat. No. 4,446,232 utilizes a combination of two different reaction zones arranged in three separate layers. The first reaction zone comprises two layers fabricated from porous material wherein the first and second layers are impregnated with soluble enzyme-linked antibody and immobilized antigen, respectively. The third layer, or second reaction zone, contains immobilized indicator reagent that will react with the enzyme linked to the antibody of the first reaction zone to produce a color. If a liquid sample contains the antigen of interest, then after the sample is applied to the first reaction zone, the antigen contained therein will bind with the soluble enzyme-linked antibody and diffuse through to the second reaction zone following a short incubation period. The presence of antigen will be detected when the enzyme reacts with the indicator reagent to produce a color. By contrast, if a liquid sample does not contain any antigen, then the enzyme-linked antibody will migrate to the second layer of the first reaction zone, aided by diffusion of the fluid test sample, where it will bind to immobilized antigen. The binding reaction that occurs will prevent any enzyme-linked antibody from reaching the second reaction zone where it would react with the indicator reagent. Thus, in this particular scenario, no color is observed indicating the lack of antigen in the fluid test sample.
While the methods and devices described above may provide compact and somewhat reliable means for performing immunodiagnostic assays, several problems regarding their use still exist. In particular, one of the disadvantages encountered in determining the presence or absence of a target analyte in the majority of cases is the requirement to perform several addition and washing steps using a range of solvents. The washing steps are essential at various stages of the assay protocol in order to prevent undesired cross-reactions and to remove any excess unbound reagents and substances which may subsequently interfere with the results. Unfortunately, this only complicates the overall procedure and effectively reduces the level of efficiency desired in order to develop an improved and simplified version of an immunodiagnostic assay. Thus, the need to adhere to several addition, washing and incubation steps has largely limited these procedures to clinical settings where skilled personnel and sophisticated equipment are available to carefully monitor and perform the assay with precision and accuracy.
In addition, immunodiagnostic assays that employ chromatographic test strips or dipsticks suffer from a problem regarding sequential treatment with one or more solvents at various stages of the assay procedure. As each solution is added to the device, or as each device immersed into successive solutions, the opportunity for spillage or contact between the solutions and the user are enhanced, thus leading to possible contamination and reduction in the reliability of the test.
Depending on the assay and device used, it is usually necessary that the test sample be diluted with an appropriate reagent prior to application so that it will diffuse more easily throughout the porous material and/or not overwhelm the concentration of the labeled reagent. However, dilution of the test sample not only reduces the speed and ease of performing an assay by including an additional step and reagent, but it can also reduce the sensitivity of an assay due to the correlation of analyte concentration to the detection signal generated.
A further disadvantage associated with the use of some immunodiagnostic devices, particularly those incorporating lateral-flow techniques, is that they characteristically require long incubation periods at various stages of the procedure. Depending on the relative mobility of the analyte of interest, the type of reagents and solvent used, and the site relationship between the different reaction zones, adequate time is essential in order to allow for efficient migration of all the various components along the chromatographic solid phase material. Moreover, the lateral flow technique often contributes to a higher incidence of inaccurate results due to the tendency of mobile reagents to accumulate at, rather than clear, the periphery of the reaction zone. As a result, these reagents will often interact at the zone and produce color products that may be easily mistaken for a true positive or negative result.
Accordingly, the present invention provides an improved rapid diagnostic device, assay and multifunctional buffer for the detection of a target analyte in a fluid test sample which is efficient, reliable and practical to perform. The simplified 2-step assay utilizes a multifunctional buffer reagent and a dual component flow-through device comprising a test unit in combination with a detachable dried indicator reagent delivery unit which are capable of receiving the fluid test sample and multifunctional buffer, respectively.
The multifunctional buffer serves as a combination washing, diluting, wetting and resolubilizing reagent, without sacrificing the sensitivity or specificity of the diagnostic assay. Additionally, the buffer is formulated to preserve and optimize protein stability, as well as minimize, if not eliminate, non-specific interactions that might lead to the generation of a false signal.

This patent is subject to a terminal disclaimer.

Rapid diagnostic device, assay and multifunctional buffer


A catalyst vessel including an inlet at an upstream end, a plurality of catalytic chambers located downstream of the conduit, wherein at least two chambers are connected by a plate having one or more orifices therein to permit gas flow through from the first chamber to the second chamber, and wherein at least one surface in the chamber is adapted for deposition of a metal selected from the group consisting of platinum, rhodium, and rhenium, and an outlet at its downstream end.

There has long been a need to employ catalysts in reactions such as simultaneous combustion leading to oxidation of carbon monoxide and unburned hydrocarbons, and the reduction of nitrogen oxides (NOx) which are emitted from automotive engines and the like. The role of catalysts, particularly three-way catalysts, in automotive emission control has been widely studied in the art. For example, Taylor, "Automobile Catalytic Converter", Catalysis, Science and Technology, pp. 119-67 (Anderson et al. eds. 1984), describes emissions control technology, composition of three-way catalysts, and catalytic supports.
Conventional systems for converting automotive exhaust gases employ pre-fabricated supported catalysts, typically a solid stratum of catalytic material, such as honeycombed ceramic structures, which are placed in the exhaust section of the automobile. As the emissions pass through the solid, the catalytic metal present on the strata aids in conversion of CO, NOx and unburned hydrocarbons to CO.sub.2, N.sub.2 and H.sub.2 O. However, the solid strata-type catalytic converter eventually becomes spent, and requires removal and replacement in the exhaust portion of the engine. Moreover, structures such as a honeycomb support are complex and relatively expensive to manufacture. State of the art systems capable of carrying out three-way catalysis include those having supported rhodium and platinum, with noble metals such as rhodium being a preferred catalyst for the reaction: EQU NO+CO.fwdarw.1/2N.sub.2 +CO.sub.2
Platinum is the preferred catalyst for the oxidation of CO and unburned hydrocarbons.
The noble metals are expensive and in limited supply, particularly rhodium. This is exacerbated by the fact that current usage of platinum and rhodium in three-way catalysis exceeds the Rh/Pt mine ratio. Thus, reduction of noble metal usage is a problem of three-way catalysis. Therefore, it is necessary to develop alternative approaches to emission control.
Accordingly, there is a need for alternative catalytic vessels capable of converting automotive emissions not utilizing conventional additional, non-regenerable solid catalytic material-containing supports in the exhaust system of an automobile. There is likewise a need for alternative catalytic vessels containing metal catalysts which convert emissions with increased efficiency in order to decrease the required supply of catalyst.


The excursion of a loudspeaker cone is estimated using a reference signal in one example, a primary signal, produced by a cone of a loudspeaker, is received and a reference signal produced simultaneously with the primary signal by the loudspeaker cone is received. The reference signal causes an excursion of the loudspeaker cone that is amplitude modulated by the excursion caused by the primary signal. An amplitude modulation of the reference signal is determined and an excursion of the loudspeaker cone is determined using the determined amplitude modulation.

In and electrodynamic loudspeaker, a cone is attached to a voice coil. The voice coil is moved by an electromagnet powered by an audio amplifier. The faster and farther the cone moves, the louder the sound from the loudspeaker. In today's mobile devices, very small loudspeakers are used in order to allow for thinner and smaller devices. Smaller loudspeakers are desired for many devices in order to reduce size and to require less power to drive the loudspeakers. At the same time, mobile devices such as mobile phones and tablet computers are typically designed to reproduce acoustic signals with high loudness.
The very small loudspeakers used in mobile phones and tablets are called micro speakers. Due to their small size, their performance is limited. The total volume and contrast are both low. As a result, these loudspeakers are often operated close to the boundary of their safe operating range.
Any electrodynamic loudspeaker is vulnerable to damage by overly large excursions of the voice coil and the cone. Typical failures are caused by the voice coil hitting the back plate or the cone suspension being torn due to excessive forward force. The loudspeakers are protected by limiting the overall amplifier power. This allows for safe operation of micro speakers with a safe distance from the boundary of the loudspeaker's safe operating area.

Loudspeaker cone excursion estimation using reference signal


A ball collecting apparatus and method of use thereof, wherein the ball collecting apparatus comprises a plurality of selectively positionable elastic members secured to a plurality of securing points on a lower portion of a frame or a removable base section connected to the frame. The plurality of elastic members are secured to user-selected securing points so that the distance between the elastic members can accommodate substantially spherical objects of different sizes. In use, the ball collecting apparatus is pressed on top of a ball or similar object, causing the elastic members to separate and allow the ball to enter and be retained within the frame. Upon entering of the ball within the frame, the elastic members retract to their original position, therein preventing the ball from falling back out.

There are various types of ball collectors or ball hoppers in existence. One discloses a device for picking up spherical material utilizing several elastic bodies stretched on a frame body part to form an opening part a little smaller than the outline of the spherical material, such as a ball, so that the spherical material expands the elastic bodies to loosely insert the spherical material from the opening part into the frame body. However, this device is limited in the size spherical objects it would be able to retrieve by the natural expansion of the elastic bodies and lacking of readily adjustable elastic members. Accordingly, it would not be suitable for picking up both ping pong balls and basketballs.
Another device discloses a system to gather table tennis balls which has a tube acting as a sleeve, with a large cylinder at its lower end having a mesh base. The mesh cords pass through holes at the lower end of the large cylinder with a gap of preferably 35 mm between the mesh cords, which are at a low tension.
Another device discloses a frame for picking up table tennis balls with a grid of parallel elastic cords stretched across it and fitted with a handle; however, the elastic cords are not readily adjustable and thus the device cannot truly accommodate substantially different size balls.
Yet another device discloses an apparatus to assist in retrieving balls and in storing balls, such as tennis balls. The apparatus comprises a bottom frame through which a ball may pass upwardly when the bottom frame is positioned over the ball and pressed firmly to the ground wherein the frame prevents the ball passing downwardly and out of the frame. The ball is retained by a member, wherein the member moves through springs attached to the frame; however, the device lacks a readily adjustable member to accommodate substantially different size balls.
Still another device discloses an apparatus for picking up balls, especially tennis balls, with a ball collection basket which has a ball inlet device in its base. The ball inlet device possesses longitudinal parts extending between two opposing lateral walls of the ball collection basket and arranged at least approximately parallel to each other and at a distance from each other and/or from the lateral walls lying at least approximately parallel thereto, this distance being slightly less than the diameter of a ball to be received. Collection or release frames, which are pivotable about a horizontal axis, are attached to the ball collection basket. The longitudinal parts are resilient; however, the device lacks readily adjustable longitudinal parts to accommodate substantially different size balls.
Another device discloses a device for retrieving table tennis or golf balls which comprises a frame with rectangular, polygonal or circular ends, between which are stretched elastic cords; however, the device lacks readily adjustable elastic cords to accommodate substantially different size balls.
Yet another device discloses a ball collector for picking up balls of different diameters. Springs or some other elastic material are stretched between two discs, as near as possible to the outside edge, in such a fashion that they run parallel to each other but are not horizontal to the ground, instead running from one disc to the other at a given angle. Additionally, a bracket with a long handle is fixed above the whole assembly to the outsides of the discs, which also function as wheels, so that the whole thing can be pushed along. When the device rolls over a ball, the springs or similar will move apart somewhat as they are pushed up and will cause the ball to end up in the reservoir on the inside. However, the device lacks readily adjustable springs or some other elastic material to accommodate substantially different size balls.
Still another device discloses an apparatus for picking up, transporting and storing balls which comprises two opposing planes separated by tension elements which when forced over a solid, hollow or pressurized sphere simultaneously stretches the tension elements and/or compresses the sphere sufficiently to permit the sphere entry between the planes. Once the sphere is between the planes it is kept in place by the forces created by the stretched tension trying to regain their original unstretched configuration and the pinched sphere trying to regain its original configuration by trying to expand out.
Another device discloses a ball retrieval and storage device for retrieving balls of at least two different sizes comprising a wheeled container with rotatably attached handled. The container is rollingly supported by two wheels on an axle, and includes a removable rack which, when in place, covers the container to ensure the contents remain within the container. When the removable rack is placed beneath the container, the entire device is elevated to prevent needless bending and stooping by the user. The device further comprises a retrieval opening which includes a fixed member and a movable member to provide variable spacing between them depending on the size ball to be retrieved. The device is placed near a ball to be retrieved, tilted backward onto its wheels, rolled forward such that the ball is beneath the opening, then returned to its upright position in order to capture a ball. The angular movement of the movable member in a direction generally upwardly and away from the fixed member allows for differing sized balls to be retrieved and stored. A resilient member retracts the movable member back to its original position following capturing of a ball.
Yet another device discloses a container for the delivery, transportation, dispensing and collection of plastic tennis balls, which container is substantially characterized by the removal of the base, except for an inward-facing flanged edge and the arrangement of longitudinally-orientated, spaced, calibrated sprung steel bars. The tennis balls are pushed in through the free gaps between the bars and their emergence at the bottom is blocked. Moreover, folding handle strands are provided which are effective either upwards as a carrying facility or collection position or downwards in the folded-down position as supporting feet.
Still another device discloses a ball retrieving and storage device which includes a container having an elongated handle extending above it, and one or more movable gate members in the bottom of the container. Balls are retrieved from the ground by placing the bottom of the container over the balls and exerting a downward force on the handle to force the balls up against the bottom of the movable gate member which opens the gate and provides an enlarged opening in the bottom of the container for allowing each ball to pass into the container. Continued downward movement causes the moving gate member to engage stop bars on opposite sides of the container for limiting further vertical movement of the gate sufficiently to allow the equator of each ball to pass through the enlarged opening and then allow the gate to automatically drop to a closed position to retain balls in the container. A cylindrical-shaped cage also is disclosed which provides a rotary type ball retriever adapted to be rolled on the ground to engage balls which automatically open gate members spaced around the outer circumference of the cage.
Another device discloses a ball retrieving and storage cart which generally comprises a wheeled carriage that rollingly supports a basket in a ball retrieving position. In an exemplary embodiment, the basket has a front end and a rear end and includes a bottom wall having two side members oriented front to rear and having a normal position spaced apart less than the ball diameter and defining a slotted aperture for entrance of a ball into the basket. In the ball retrieval position, at least one of the side members is a slanted member having a front end higher from the ground than a ball radius and a rear end lower to the ground than the ball radius. At least one of the side members is a deflectable member and is biased to the normal position but is sideways deflectable such that a ball on the ground entering the aperture sideways deflects the deflectable member sufficiently for the ball to pass into the basket. The wheels may define a rolling plane. The carriage includes a vertical frame member terminating in a push handle and the vertical frame member includes brackets for attaching a moveable basket at a serving position that is higher than the ball retrieving position.
Yet another device discloses a ball retrieval and storage device which includes a container having a hollow interior for storing a substantial number of tennis balls. At least a portion of the container bottom is formed by one or more movable rod members which are movable to allow the balls to enter through the bottom of the container. A user can retrieve a ball lying on the ground by forcing the bottom of the container down over the top of the ball. The ball engages the movable rod member and moves it slightly upwardly which allows the ball to enter the container as the container is progressively forced down over the top of the ball compressing the ball. The movable rod members are formed of a material having an elastic memory such that for use over time, the movable rod members will not permanently deform so as to decrease the efficacy of the ball retrieval and storage device.
Still another device discloses a ball retrieving and storage device including a storage container having a pair of handles hingedly fixed thereto which may be folded to a downwardly extending position supporting the container on a playing surface. The retrieving device includes a plurality of parallel rods extending across the bottom of the container. The rods are spaced apart from one another a distance greater than the diameter of the balls to be retrieved and being slightly resilient in a direction perpendicular thereto. Each of the rods has journaled thereon a hollow, cylindrical tubular roller to provide for a rotating movement, wherein the distance between inside surfaces of adjacent parallel rollers is slightly less than the diameter of a used tennis ball. The transverse resilience of the rods and the rotating motion of the rollers permit a ball to be retrieved by forcing the bottom of the container down over the ball. When folded upwardly the handles of the container enable an operator to both carry and retrieve balls from a playing surface without bending or stooping. When a substantial number of balls are held within the container, the handles may be folded into a downwardly extending position to support the container at a convenient height for the removal of balls.
Another device discloses a ball-picking device which is utilized to pick up a ball on a ground surface, and includes a basket frame unit which confines a ball receiving space and which has a ground contacting side formed with a plurality of ball-extension gaps that are in spatial communication with the ball receiving space. Each of the ball-extension gaps is confined by a pair of deformable, yet not elastic, rod units, and is slightly narrower than a diameter of the ball such that when the ground contacting side of the basket frame unit is moved toward the ground surface to register the ball with one of the ball-extension gaps, the deformable rod units that define a respective one of the ball-extension gaps will be pushed apart and will be deformed by the ball so as to enlarge the respective ball-extension gap and permit extension of the ball into the ball receiving space. However, the device lacks readily adjustable deformable rod units to accommodate substantially different size balls.
Yet another device discloses a sports ball retrieval and storage device which includes a receptacle, a pair of support members and a lid. The receptacle is in the form of a molded one-piece body made of substantially rigid material and having a plurality of side walls and a bottom grate integrally connected together so as to define an open top and an interior chamber of the receptacle. The side walls and bottom grate are formed of respective upper and lower annular perimeter members and laterally spaced-apart elongated members extending between and integrally connected at opposite ends with opposite portions of the upper and lower annular perimeter members. The side walls converge toward one another from the open top to the bottom grate of the receptacle and thereby provide the molded one-piece body of the receptacle with a tapered configuration permitting receptacles of multiple devices to nest with one another. The elongated members of the bottom grate are spaced apart at a distance slightly less than the diameter of a tennis ball so as to define at least one opening therebetween through which a compressed tennis ball can be forced into the interior chamber. The support members are pivotally mounted to the receptacle and convertible relative thereto between stand and handle positions. The lid is mounted to the receptacle for opening and closing the open top thereof.
Still another device discloses a tennis ball collector with drum cage, wherein the drum's peripheral surface has axially parallel bars between its end flanges which are in the form of discs or tires. The U-shaped handle has sides each of which has an angled part which, together with the middle of the U-shaped handle, forms a U-shaped stand. Wheels are attached to the angled parts which have a profiled grip surface.
Another device discloses a collapsible ball retriever and storage unit which is in the form of a receptacle composed of a plurality of side grills pivotally hinged one to the next, and a top gate and a bottom grate being pivotally hinged to respective ones of the side grills. The side grills are pivotable relative to one another to convert them between erected and collapsed positions, whereas the top gate and bottom grate are pivotable relative to the side grills to convert the top gate and bottom grate between closed and retracted opened positions. The gate and grate are latchable to others of the side grills disposed opposite to the ones thereof to which the gate and grate are respectively hinged. The bottom grate is adapted to rigidly retain the side grills in their erected position when the bottom grate is disposed in the closed position. Further, the bottom grate has members defining ball passages therethrough which adapts the receptacle for retrieving and storing balls when the side grills are in the erected position and the bottom grate is in the closed position.
Yet another device discloses a tennis ball retriever includes a cylindrical collection drum having circular cylinder bases spaced from one another. The cylindrical collection drum has openings formed in a peripheral cylinder region such that balls can be pushed therethrough. The circular cylinder bases have sleeves extending along the cylinder axis. A removable handle includes two arms extending away from the cylinder axis. The arms have stub axles at their ends such that the stub axles extend along the cylinder axis and are rotatably journaled in the sleeves. The removable handle is resiliently deformable for moving the stub axles away from the sleeves so that the cylindrical collection drum can be removed from the handle. A ball retrieving and storing system is also provided. The ball retrieving and storing system includes at least two cylindrical collection drums and a removable handle.
Still another device discloses a tennis ball retriever and storage unit includes a ball retrieving receptacle supported by spring biased pivoting wheel assemblies for rolling movement between locations for retrieving used tennis balls and downwardly movement from a normal upper transport position overlying a tennis ball to a lower position for retrieving the tennis ball between spaced rigid bars in the base of the receptacle.
Due to the constraints of current devices for picking up balls, one typically must buy a different type of ball collector for each type of ball. Although some devices claim to pick up different types and shapes of spherical objects, upon closer evaluation it can be seen that the devices are designed to pick up an object of one size, but the devices themselves may be manufactured to different sizes, enabling a plurality of devices to pick up different size objects. Thus, currently existing devices fail to adjust to accommodate different size spherical objects and multiple devices must be purchased to pick up and store different size balls.
Therefore, it is readily apparent that there is a need for a ball collecting apparatus and method of use thereof which minimizes and/or overcomes these deficiencies by providing a ball collector which is adjustable to user selected points to pick up, retrieve, and store spherical objects of different diameters. This would serve the functions of reducing cost, time, inefficiencies and multiplicity of machines while providing maximum customer satisfaction through a single ball collector. In particular, there is a need for a device that obviates repetitive bending over, thereby preventing stresses, discomfort and/or damage to the user's back. Further, there is a need for a device that is portable for moving collected objects to another location.

Ball collecting apparatus and method of use thereof


Sensor-holding lid for a wheel hub bearing, the lid presenting a base wall which is externally delimited by a peripheral border, an axial ledge which is integral to the wall and which is provided with a passing hold for housing the sensor, and a cylindrical wall which is transverse to the base wall and which is arranged radially inside the peripheral wall in order to be fixed onto an external border of the bearing; at least two annular static sealing elements which are made of rubber and which are co-molded, respectively, into the peripheral border on the outside of the cylindrical wall and inside an entry border of the passing hole.

In general, sensor-holding lids of a well-known type comprise a base wall which is externally delimited by a circular border, an axial ledge which is integral to the wall and which is provided with a passing hole for housing the sensor, and a cylindrical wall which is provided with a passing hole for housing he sensor, and a cylindrical wall which is transverse to the base wall and which is arranged radially inside the circular border in order to be fixed onto an annular border to the rolling race outside the bearing.
Due to the extremely poor environmental conditions in which the bearing has to operate and which result in the infiltration of liquid via the hole for the sensor into the inside of the bearing itself, the latter is further provided with a waterproof sealing shield which is arrange din a position substantially facing the lid, which is, in turn, provided with one or two passing draining channels which are obtained in proximity to the circular border in order to stop any liquid stagnating between the shield and the lid themselves.
The waterproof shield is, obviously, an additional element which increases the production costs of he wheel bearing, as well as increasing the axial dimensions, and, furthermore, does not completely protect the bearing from any eventual breakage caused by the liquid which, despite the presence of the draining channels, can still stagnate and freeze at low temperatures.


This power breaker has an arcing chamber which is filled with an insulating medium and extends along a central axis (2). This arcing chamber is provided with a power current path which has two erosion contact arrangements (5, 6) which are arranged on the central axis (2), are at a constant distance from one another in the axial direction and bound an arcing zone. The arcing chamber also has a heating area (13), which is connected to the arcing zone, and a bridging contact which electrically conductively connects the erosion contact arrangements (5, 6) in the connected state. The bridging contact is arranged centrally in the interior of the erosion contact arrangements (5, 6). An annular gap (36) is provided between the erosion contact arrangements (5, 6) and opens directly into the heating area (13). In this power breaker, the flow behavior is significantly improved in the region between the arcing zone and the heating area (13).

1. Field of the Invention
The present invention relates to a power breaker having at least one arching chamber filled with an insulating medium.
2. Discussion of Background
Patent Specification EP 0 3 13 813 B1 discloses a power breaker whose arcing chamber has erosion contacts, the two of which are moved in opposite directions, to be precise by a drive, which is not illustrated, in conjunction with two toothed racks, which are arranged diametrically opposite one another, and in conjunction with corresponding gear wheels.
Laid-Open Specification DE 42 11 158 A1 discloses a power breaker which has an arcing chamber with two erosion contacts, one of which is designed to be moving. The arcing chamber is filled with an insulating gas, preferably pressurized SF.sub.6 gas. Arranged concentrically around the erosion contacts is a rated current path, which carries the current when the arcing chamber is in the connected state. Provided in the interior of the moving erosion contact is a heating area to which hot gas at an increased pressure is applied from the arcing zone of the arcing chamber. The heating area is connected by means of a narrow heating channel to the arcing zone. This heating channel is designed to be comparatively long and has a right-angle bend. This bend impedes the hot gas produced by the arc flowing into the heating area, since it reflects pressure waves. These pressure waves partially block the flow in the direction of the heating area. When the process of blowing out the arc starts, this bend thus also impedes the flow into the arcing zone, therefore somewhat reducing the cooling effect of the blowing process. During disconnection, the heating area is additionally fed with cold gas from a compression area, in a known manner.
Patent Specification EP 0 163 943 B1 discloses a concentrically constructed power breaker which has one power current path which is concentrically surrounded by an axially extending heating area. The power current path has a moving erosion contact and a stationary erosion contact. Located between the erosion contacts and the heating area there is an intermediate area. After contact disconnection, the insulating gas is first of all heated up in the intermediate area by the arc which is then produced. This intermediate area enlarges the arcing zone in this power breaker. The arcing zone in this power breaker is connected by means of an annular gap, which extends radially outwards, to the heating area, which is arranged symmetrically with respect to the annular gap and into which the hot gas produced in the arcing zone flows. The hot gas is temporarily stored in this heating area. The heating area is rigidly connected to the stationary erosion contact. In this embodiment of the power breaker, the cold insulating gas in the heating area is not mixed particularly effectively with the hot gas flowing in during the disconnection process. In addition, the pressure rise in the heating area takes place with a certain time delay, since time is required in advance to heat up the insulating gas in the intermediate area.
Laid-Open Specification DE 42 00 896 A1 discloses a power breaker which has an arcing chamber with an external rated current path and two stationary erosion contacts which are at a distance from one another. The arcing chamber is filled with an insulating gas, preferably pressurized SF.sub.6 gas. When the arcing chamber is in the connected state, the two erosion contacts are electrically conductively connected to one another by means of a moving bridging contact. The bridging contact concentrically surrounds the cylindrically designed erosion contacts. The bridging contact and the two erosion contacts form a power current path, which carries current only during the disconnection process. During a disconnection process, the bridging contact slides down from a first of the erosion contacts and strikes an arc which initially burns between the first erosion contact and the end of the bridging contact facing it. As soon as this end reaches the second erosion contact, the base of the arc commutates from the end of the bridging contact onto the second erosion contact, and the arc now burns between the two erosion contacts. The gas which is heated in the arcing zone flows through a long heating channel into a heating area which is arranged in the interior of the bridging contact and where it is temporarily stored. The heating area is additionally fed, in a known manner, with cold gas from a compression area during the disconnection process. The pressurized insulating gas which is required to blow out the arc is then introduced into the arcing zone through the heating channel. The comparatively long heating channel causes considerable flow resistance, and the energy lost because of flow losses is then not available for blowing out the arc.


A handle-latch assembly mounted on a horizontal sliding door and coupled to a vertically movable latch bolt which protrudes outwardly from a top or bottom door edge, and which enables the inside and outside handles of the door to be respectively used for moving the door in closing and opening directions. The door has a manual lock actuator on the inside of the door, and an optional key-lock actuator on the outside of the door, whereby latching the door in the closed position requires a deliberate manual manipulation of either the inner lock actuator or the outer key actuator. The assembly permits sequential unlocking and opening of the door from the inside by application of a single horizontally-directed force to the inner handle. The handle-latch mechanism includes cooperating linkages, and the linkages are automatically reset into an unlocked position whenever the locked door is opened from the inside.

Sliding doors supported solely for substantially horizontal sliding movement are conventionally utilized within building interiors, such as office buildings, to separate various areas of the building. Such sliding doors are particularly desirable in commercial environments since the door does not protrude into adjacent hallways or workspaces, and hence permits more efficient utilization of adjacent spaces. A disadvantage associated with such sliding doors, however, is encountered when locking of the door, such as for privacy purposes, is desired. The force and motion required for opening and closing a sliding door is horizontally directed, in contrast to the typical rotary force and motion utilized with door handles mounted on swinging doors. When it is desired to permit selective locking of a sliding door for privacy purposes, the door is typically provided with a separate mechanism which requires separate manual manipulations. This is further complicated when the sliding door is provided with a latching bolt which moves vertically and protrudes outwardly from an upper or lower edge of the door, although this latter type of latching bolt is typically preferred since it provides greater flexibility in most use environments.
Pending U.S. application Ser. No. 10/424,260 illustrates therein a handle-latch assembly for a horizontal sliding door which addresses the above concerns by permitting sequential unlocking and opening of a horizontal sliding door by application of a single-direction force and motion to the door handle to facilitate egress. While the mechanism disclosed in this application represents a desirable approach with respect to improving on latching arrangements for sliding doors, nevertheless the aforementioned mechanism is not believed to provide a comprehensive overall solution, and the present invention is believed to provide additional improvements with respect thereto.
More specifically, this invention relates to an improved handle-latch assembly which mounts on a horizontal sliding door and couples to a vertically movable latch bolt which protrudes outwardly from one of the top or bottom edges of the door, and which enables the inside and outside handles of the door to be respectively used for moving the door in closing and opening directions, with the door also having a manual lock actuator on the inside of the door and an optional key-lock actuator on the outside of the door, whereby latching of the door in the closed position requires a deliberate manual manipulation of either the inner lock actuator or the outer key actuator. The mechanism, however, permits sequential unlocking and opening of the door from the inside thereof solely by application of a generally single horizontally-directed force to the inner handle, whereas when the door is in the closed and latched position it can be opened from the outside thereof only by first manually releasing the lock through utilization of the separate key actuator. The handle-latch mechanism includes cooperating linkages which facilitate the above functions, and which ensure that these linkages and specifically the locking linkage is automatically reset into its unlocked position whenever the locked door is opened from the inside thereof due to manipulation of the inner handle.
Other objects and purposes of the invention will be apparent to persons familiar with constructions of this general type upon reading the following specification and inspecting the accompanying drawings.
Certain terminology will be used in the following description for convenience in reference only, and will not be limiting. For example, the words "upwardly", "downwardly", "rightwardly" and "leftwardly" will refer to directions in the drawings to which reference is made. The words "inwardly" and "outwardly" will refer to directions toward and away from, respectively, the geometric center of the door or designated parts of the door handle and locking mechanism. The words "inside" and "outside" will refer to opposite sides of the door, although it will be appreciated that these terms as they are used in relationship to the invention and its orientation with respect to the door can obviously be reversed. Said terminology will include the words specifically mentioned, derivatives thereof, and words of similar import.

Single-action egress lock for a sliding door


An obstructed coronary artery is bypassed by forming a first blood flow path from a left ventricle of the heart to a coronary vein associated with the obstructed coronary artery. A second blood flow path is formed form the obstructed coronary artery to the right ventricle for blood to flow from the left ventricle through the coronary vein to the myocardium and subsequently through the coronary artery to the right ventricle in a blood flow direction opposite a normal blood flow direction in the coronary artery and coronary vein.

1. Field of the Invention
This invention pertains to a method and apparatus for performing a coronary artery bypass procedure. More particularly, the present invention reverses flow in a portion of a coronary artery and a coronary vein to direct flow from an oxygenated chamber of the heart through the vein in a direction opposite normal flow and from the myocardium through the artery in a direction opposite normal flow and into a reduced pressure chamber of the heart.
2. Description of the Prior Art
Coronary artery disease is the leading cause of premature death in industrialized societies. Numerous techniques have been developed for bypassing an obstructed or diseased coronary artery. Angioplasty attempts to expand an occluded site. Commonly, a balloon-equipped catheter is used to expand an occluded site. A stent may be placed at the expanded site for the purpose of preventing reblockage. Coronary artery bypass grafting uses a harvested blood vessel from the patient to graft a bypass from the aorta to the occluded artery. Such prior art procedures have numerous problems including restenosis of angioplasty treated vessels. Grafting techniques are highly traumatic and present other problems.
New methods have been proposed as alternatives to traditional angioplasty and bypass grafting. These methods include providing a direct blood flow path from the left ventricle directly through the heart wall to the coronary artery and are described in U.S. Pat. Nos. 5,429,144, dated Jul. 4, 1995; 5,287,861, dated Feb. 2, 1994; and 5,409,019, dated Apr. 25, 1995 (all to Wilk). All of these techniques include providing a stent in the heart wall to define a direct flow path from the left ventricle of the heart to the coronary artery. The stent is closed during either diastole or systole to block return flow of blood from the coronary artery during the heart's cycle. For example, the '861 patent teaches a stent which collapses to a closed state in response to heart muscle contraction during systole. The '019 patent (particularly FIGS. 7A and 7B) teaches a rigid stent (i.e., open during systole) with a one-way valve which closes during diastole to block return flow of blood from the coronary artery. Such techniques for interruption of blood flow during either diastole or systole are undesirable since such interruption can result in areas of stagnant or turbulent blood flow. Such areas of stagnation can result in clot formation which can result in occlusion or thrombi breaking loose. Providing direct blood flow from the left ventricle to the coronary artery has been criticized. For example, Munro et al, "The Possibility Of Myocardial Revascularization By Creation of a Left Ventricle Coronary Artery Fistula", 58 Journal Thoracic and Cardiovascular Surgery, pgs. 25-32 (1969) shows such a flow path in FIG. 1. Noting a fallen coronary artery flow and other adverse consequences, the authors concluded "that operations designed to revascularize the myocardium direct from the cavity of the left ventricle make the myocardium ischemic and are unlikely to succeed." id at pg. 31.
In addition to the foregoing, techniques have been developed to directly revascularize the myocardium. For example, U.S. Pat. No. 5,429,144 to Wilk (FIGS. 10-12) teaches passing a stent from either the coronary artery or the left ventricle directly into but not through the myocardium for direct revascularization of the myocardium. However, these techniques are unsuitable. For example, Roque Pifarre, M.D. et al, in "Myocardial Revascularization From the Left Ventricle: a Physiological Impossibility", 19 Surgical Forum, 157-159 (1968), concluded that blood flow from the ventricular lumen to the myocardium to artificially create channels is a physiologic impossibility due to pressure differentials. Also, supplying a flow of blood to the myocardium without adequate drainage of blood from the myocardium can result in heart swelling and edema.

Coronary artery bypass with reverse flow


A method and apparatus for decoding a signal in the presence of linear or nonlinear interference, correlated noise or a combination thereof. The method involves a concatenated decoder comprising an inner decoder and a postprocessor. N most likely paths are generated by the inner decoder, or a combination of the inner decoder and an error event generator. These paths are then presented to the postprocessor which computes metrics for each path based on information about the signal, not considered by the inner decoder. These metrics can be based on linear or nonlinear model of the channel and optionally, a noise whitened signal for noise decorrelation. The path with the best metric is selected as the concatenated decoder output. The postprocessor can also be implemented in the presence of channel codes. It is also shown that the postprocessor is especially suited for a trellis implementation. When applied to magnetic recording channels, the method of the present invention allows for increased recording capacity. In addition, the present invention requires less computation and results in a reduction of the power dissipation of about two orders of magnitude compared to alternative approaches.

Magnetic recording systems are commonly used for secondary storage in computer systems. As a result of the widespread use of, and growing applications for computers, there is a continuous demand for increased storage capacity. Therefore, methods and apparatus for increasing recording densities, the amount of information stored in a given volume, are continuously explored.
As recording density increases, the electronic pulses induced on the read heads by adjacent bits increasingly tend to interfere and partially cancel each other, resulting in a decrease of the intensity of the detected signal. In addition, the noise increases as a result of various effects, such as the interference from nearby tracks. The net result is that the signal to noise ratio ("SNR") tends to decrease rapidly with increased recording density. Accordingly, with increased densities, there is also a need for more advanced signal processing techniques.
One of the signal processing techniques that has resulted in significant increases in density is known as "Partial Response Maximum Likelihood" (PRML). This technique was introduced in H. Kobayashi and D. T. Tang, Application of Partial-Response Channel Coding to Magnetic Recording Systems, 14 IBM Journal of Research and Development pp. 368-375 (July 1970), hereby incorporated by reference as if fully set forth herein, but not applied to disk drive systems until very recently. In this technique, the discrete-time channel response is shaped by means of an adaptive filter called an Equalizer, in such a way that its transfer function, expressed as a D-transform, is EQU H(D)=1-D.sup.2 ( 1)
This response is usually known as "Partial Response Class IV" (PR IV), and was first described in A. Lender, Correlative Level Coding for Binary Data Transmission, 3 IEEE Spectrum pp. 106-115 (February 1966), and E. R. Kretzmer, Generalization of a Technique for Binary Data Communication, COM-14 IEEE Transactions on Communications pp. 67-68 (February 1966), and further developed by P. Kabal and S. Pasupathy, Partial-Response Signalling, COM-23 IEEE Transactions on Communications (September 1975), all three of which are hereby incorporated by reference as if fully set forth herein.
PRML is the result of combining PR IV with another technique called "Maximum Likelihood Detection", introduced in A. J. Viterbi, Error Bounds for Convolutional Codes and an Asymptotically Optimum Decoding Algorithm, IT-13 IEEE Transactions on Information Theory pp. 260-269 (April 1967), and further developed in G. D. Forney, Maximum-Likelihood Sequence Estimation of Digital Sequences in the Presence of Intersymbol Interference, IT-18 IEEE Transactions on Information Theory (May 1972), and G. D. Forney, The Viterbi Algorithm, 61 Proceedings of the IEEE pp. 268-278 (March 1973), all three of which are hereby incorporated by reference, as if fully set forth herein. Other types of partial responses of interest in magnetic recording channels are described in H. K. Thapar and A. M. Patel, A Class of Partial Response Systems for Increasing Storage Density in Magnetic Recording, MAG-23 IEEE Transaction on Magnetics pp. 3666-3668 (September 1987), hereby incorporated by reference as if fully set forth herein. These responses are of the general type EQU H(D)=(1-D)(1+D).sup.n ( 2)
The case of PR IV mentioned above is a special case of this equation, for which n=1. Another case of interest in the context of the present invention is the case of n=2, a response known as "Extended Partial Response Class IV", or EPR IV.
A maximum likelihood sequence detection ("MLSD") scheme determines the sequence of data symbols that best matches an observed sequence of signal samples that have been corrupted by noise and interference. A common implementation of an MLSD scheme involves the Viterbi algorithm. The Viterbi algorithm performs maximum likelihood sequence detection of finite state signals in noise.
In many situations, the state space is too large to search directly. One example of such a situation is when the channel response extends over a long time. In general, if the number of nonzero samples of the channel impulse response is L, the number of states required for an optimal Viterbi decoder for binary data is 2.sup.(L-1). Thus the complexity of the optimal decoder grows exponentially with the length of the channel impulse response. In these situations, suboptimal detection techniques may provide a reasonable tradeoff between performance and complexity.
Concatenated decoding schemes are an example of suboptimal detection schemes whose performance often approaches the performance of the optimal decoder and whose complexity is substantially lower. One exemplary concatenated decoding scheme is found in N. Seshadri and C. E. W. Sunberg, Generalized Viterbi Algorithms for Error Detection with Convolutional Codes, Proceedings of Globecom 89, pp. 1534-1538, hereby incorporated by reference as if fully set forth herein. This scheme as well as others of its kind, include a modified Viterbi algorithm in which an ordered list of an arbitrary number ("N") of best paths and their corresponding likelihoods, each corresponding to a sequence of data which may reflect the transmitted sequence of data, are produced while an error detection code chooses the first error-free path from the list.
An alternative to an N-best Viterbi algorithm is to generate a list of candidate data sequences by adding minimum-distance error events to the single best path released by the Viterbi decoder. This scheme was used in decoding DC-free block codes in partial response channels in K. Knudson, et al., A Concatenated Decoding Scheme for (1-D) Partial Response with Matched Spectral Null Coding, Proceedings of GLOBECOM 93, hereby incorporated by reference as if fully set forth herein. The inner decoder ignores the code constraints, while a postprocessor eliminates the sequences that violate the constraints.
As mentioned, increased storage density tends to increase the amount of interference between adjacent bits and tracks. The interference among adjacent bits is referred to as intersymbol interference ("ISI"), and the interference between adjacent tracks is called intertrack interference ("ITI"). Specifically, ISI occurs because the detected pulses are not properly confined to their time slot, i.e., baud period, available to the reading of a single data symbol. As a result, the neighboring pulses interfere with each other and degrade the margin against random noise available to the detector.
Owing to the importance of storage capacity of magnetic recording systems, various methods have been proposed for compensating ISI. The most common of such methods is equalization, which is well known to those skilled in the art. Another method using tentative decisions is described in O. E. Agazzi and N. Seshadri, Cancellation of Precursor Intersymbol Interference in Magnetic Recording Channels, U.S. patent application Ser. No. 08/381,630, filed on Jan. 31, 1995, hereby incorporated by reference as if fully set forth herein.
Intersymbol interference is, however, only one of the many impairments that limit the storage density. Other impairments include intertrack interference, as mentioned above, and nonlinear distortion. Nonlinearity arises in the magnetic recording channel as a result of factors such as the hysteresis of the magnetic material. It may also arise as a result of the nonlinear transfer characteristic of certain heads, known as magnetoresistive heads.
Nonlinear distortion can be considered a generalized intersymbol interference. A more complete description of nonlinear distortion in data transmission systems is discussed in O. E. Agazzi et al., Nonlinear Echo Cancellation of Data Signals, COM-30 IEEE Transactions on Communications pp. 2421-2433 (November 1982) and in O. E. Agazzi et al., Timing Recovery in Digital Subscriber Loops, COM-33 IEEE Transactions on Communications pp. 558-569 (June 1985), both of which are hereby incorporated by reference as if fully set forth herein. Another description is given in R. Hermann, Volterra Modeling of Digital Magnetic Saturation Recording Channels 26 IEEE Transactions on Magnetics pp. 2125-2127, App. A (September 1990), hereby incorporated by reference as if fully set forth herein. These descriptions can also be applied to nonlinear distortion in magnetic recording channels.
Write precompensation techniques are known in the prior art and are useful for compensating part of the nonlinearity in magnetic recording channels. However, write precompensation is not perfect, and substantial nonlinearity remains in the precompensated signals. This motivates the use of other techniques to alleviate the detrimental effects of nonlinearity.
One possible technique would be cancellation as, for example, based on tentative decisions, as is used for linear intersymbol interference and described in the above referenced U.S. Patent Application. However, it has been shown that cancellation is not effective for the case of nonlinearity. The reasons for this lack of effectiveness are explained in O. E. Agazzi and N. Seshadri, When Can Tentative Decisions be Used to Cancel (Linear or Nonlinear) Intersymbol Interference? (With Application to Magnetic Recording Channels), Proceedings of the 1995 International Conference on Communications pp. 647-652 (Seattle, Washington, June 1995), hereby incorporated by reference as if fully set forth herein.
Another possible technique to mitigate the effects of nonlinearity in magnetic recording channels is to implement the Viterbi algorithm to perform a maximum likelihood sequence detection based on a model of the channel that incorporates a complete description of the nonlinearity. In this technique, the branch metric associated with the transition between two arbitrary states S.sub.n-1 and S.sub.n is given by (y.sub.n -F(a.sub.n, a.sub.n-1, . . . , a.sub.n-M+1)).sup.2 where y.sub.n is the most recent sample of the received signal, a.sub.n, a.sub.n-1, . . . , a.sub.n-M+1 are the M bits associated with the transition between states S.sub.n-1 and S.sub.n, and F() is a nonlinear function that models the channel. This nonlinear function is usually not known a priori, but it can be estimated using nonlinear adaptive filtering techniques well known in the prior art. See, e.g. O. E. Agazzi et al., Nonlinear Echo Cancellation of Data Signals, supra and N. Holte and S. Stueflotten, A New Digital Echo Canceler for Two-Wire Subscriber Lines, COM-29 IEEE Transactions on Communications (November 1981), hereby incorporated by reference as if full set forth herein.
Although in principle this method provides the optimal performance, a major problem is its complexity. As was mentioned before, the complexity of the Viterbi decoder grows exponentially with the length of the channel response. This applies both to the linear and the nonlinear case.
A related problem is that often a significant portion of the nonlinear components of the channel response appear as "precursors," components that precede in time, the appearance of the main component of the channel response. These precursors can, in principle, be taken into account by a nonlinear channel estimator in the Viterbi decoder. However each additional precursor that is accounted for results in doubling the number of states.
Another related problem is that the Viterbi decoder is optimal only if the noise at its input is white. This is usually accomplished by using a whitened matched filter at the input stage of the receiver, as described in G. D. Forney, Maximum-Likelihood Sequence Estimation of Digital Sequences in the Presence of Intersymbol Interference, supra. However the use of a whitened matched filter often results in exceedingly long channel responses and requires a Viterbi decoder with an impracticable number of states. In application, this problem is usually circumvented by not using a whitened matched filter at the input stage of the receiver. However, this results in substantial loss of performance. The problem of the exponential growth of the complexity of the Viterbi decoder is exacerbated even more when a channel code is used, and it is desired to perform joint decoding of the channel and the code.
A primary motivation for the present invention is that, in order to keep the complexity of the Viterbi decoder within reasonable bounds, it is necessary to limit the number of its states. As a result, the Viterbi decoder often operates under "mismatched conditions," which means that it uses a simplified model of the channel that ignores the components of the channel response which result in linear and nonlinear intersymbol interference, and it ignores noise correlation. The resulting increase in the error rate is compensated through postprocessing techniques aimed at correcting a large fraction of the errors that arise from the mismatch.

Method and apparatus for compensation of linear or nonlinear intersymbol interference and noise correlation in magnetic recording channels


A stent graft for placement in a lumen of a patient is disclosed. The stent graft comprises: a main tubular body of a biocompatible graft material having a main lumen, the main tubular body having a proximal end and a distal end; a side arm extending from the main tubular body, the side arm having a side arm lumen, the side arm lumen being in fluid communication with the main lumen through a side arm opening in the main tubular body; and a cannulation pocket. The pocket comprises: an exit aperture positioned opposite the side arm opening; an entry aperture longitudinally spaced from the entry aperture in a direction toward the distal end of the main tubular body; and a wall, the wall laterally spaced from the main lumen so as to provide a guide surface for a cannula fed through the entry aperture.

There exist endovascular stent grafts which can be deployed into the vasculature system so as to treat aortoiliac aneurysms. It is often necessary to produce stent grafts that have branches, the branches arranged to match anatomical branches in the vascular system.
Branched endovascular stent grafts for use in treating aortoiliac aneurysms require the insertion of a covered stent to bridge the gap between the endovascular graft and the internal iliac artery. A preferred method of introducing the covered stent is to insert the stent through the iliac/femoral artery on the contralateral side and guide the stent up and over to the ipsilateral side where it is deployed (the "up and over" approach). With some stent grafts, a fenestration or valve is provided in the wall of the stent graft to allow temporary access for a catheter to allow deployment of the covered stent through the iliac/femoral artery.
The above-described up and over access from the contralateral side is not ideal for all patients.
Stent grafts having fenestrations or valves are difficult to design and manufacture for patients with short common iliacs because of the lack of room on the stent graft in the region of the common iliac. Furthermore, difficulties can arise in design of closing mechanisms for valved fenestrations.
It is an object of the present invention to provide an improved stent graft that ameliorates the aforementioned problem(s) or at least offers a useful choice
Throughout this specification, when discussing the application of this invention to the aorta or other blood vessels, the term "distal" with respect to a prosthesis is intended to refer to a location that is, or a portion of the prosthesis that when implanted is, further downstream with respect to blood flow; the term "distally" means in the direction of blood flow or further downstream. The term "proximal" is intended to refer to a location that is, or a portion of the prosthesis that when implanted is, further upstream with respect to blood flow; the term "proximally" means in the direction opposite to the direction of blood flow or further upstream.

Endovascular graft having a cannulation pocket


Techniques are provided for resynchronizing instances of a replicated table. In one embodiment, a database server is provided as a member of a plurality of communicatively coupled database servers. Each database server is configured to support a replicating mode of operation and a non-replicating mode of operation. The instances of the replicated table are resynchronized responsive to a user request, without stopping any of the plurality of database servers and without requiring any of the plurality of database servers to operate in the non-replicating mode of operation.

1. Field
This invention relates to a database management system; and in particular, this invention relates to online repair of a replicated table.
2. Description of the Related Art
Database management systems allow large volumes of data to be stored and accessed efficiently and conveniently in a computer system. In a database management system, data is stored in database tables which organize the data into rows and columns. FIG. 1 depicts an exemplary database table 24 which has rows 26 and columns 28. To more quickly access the data in a database table, an index may be generated based on one or more specified columns of the database table. In relational database management systems, specified columns are used to associate tables with each other.
The database management system responds to user commands to store and access data. The commands are typically Structured Query Language (SQL) statements such as SELECT, INSERT, UPDATE and DELETE, to select, insert, update and delete, respectively, the data in the rows and columns. The SQL statements typically conform to a SQL standard as published by the American National Standards Institute (ANSI) or the International Standards Organization (ISO).
Departments within an enterprise may have their own database management systems, typically at different sites. An enterprise typically wants to share data among the departments throughout the enterprise. A technique called replication is used to share data among multiple database management systems.
A replication system manages multiple copies of data at one or more sites, which allows the data to be shared among multiple database management systems. Data may be replicated synchronously or asynchronously. In synchronous data replication, a two-phase commit technique is used. In a two-phase commit, a transaction is applied only if all interconnected distributed sites agree to accept the transaction. Typically all hardware components and networks in the replication system must be available at all times in synchronous replication.
Asynchronous data replication allows data to be replicated on a limited basis, and thus allows for system and network failures. In one type of asynchronous replication system, referred to as primary-target, all database changes originate at the primary database and are replicated to the target databases. In another type of replication system, referred to as update-anywhere, updates to each database are applied at all other databases of the replication system.
An insert, update or delete to the tables of a database is a transactional event. A transaction comprises one or more transactional events that are treated as a unit. A commit is another type of transactional event which indicates the end of a transaction and causes the database to be changed in accordance with any inserts, updates or deletes associated with the transaction.
In some database management systems, a log writer updates a log as transactional events occur. Each transactional event is associated with an entry or record in the log; and each entry in the log is associated with a value representing its log position.
When a replication system is used, a user typically specifies the types of transactional events which cause data to be replicated. In addition, the user typically specifies the data which will be replicated, such as certain columns or an entire row. In some embodiments, the log writer of the database management system marks certain transactional events for replication in accordance with the specified types of transactional events. The replication system reads the log, retrieves the marked transactional events, and transmits the transactional events to one or more specified target servers. The target server applies the transactional events to the replicated table(s) on the target server.
A replicated table may need to be repaired under certain circumstances. For example, a replicated table may need to be repaired if it was taken out of replication for some duration of time, if some of the rows of that table failed to be replicated due to errors, or if the table was newly added into the replication topology and a user wants to bring the table up-to-date. In some replication systems, replication is stopped to repair a table.
Various database management systems operate in a non-stop environment in which the client applications using the database management system cannot be shut down. However, stopping replication may stop the database management system and therefore the client applications. Thus, there is a need for a technique to repair a replicated table without causing downtime to the client applications in the replication environment. The technique should repair a replicated table without requiring replication to be stopped.

International Business Machines Corporation


A method of forming a double-gated junction field effect transistors (JFET) and a tri-gated metal-oxide-semiconductor field effect transistor (MOSFET) on a common substrate is provided. The double-gated JFET is formed in a first region of a substrate by forming a semiconductor gate electrode contacting sidewall surfaces of a first channel region of a first semiconductor fin and a top surface of a portion of a first fin cap atop the first channel region. The tri-gated MOSFET is formed in a second region of the substrate by forming a metal gate stack contacting a top surface and sidewall surfaces of a second channel region of a second semiconductor fin.

The present application relates to semiconductor device fabrication, and more particularly, to formation of junction field effect transistors (JFETs) and metal-oxide-semiconductor field effect transistors (MOSFETs) on a common substrate.
Junction field effect transistors (JFETs) have unique advantages over metal-oxide-semiconductor field effect transistor (MOSFETs) for certain applications such as, for example, analog circuits. Therefore it is desirable to integrate JFETs and MOSFET on the same chip, particularly for system-on-chip (SoC) applications, without a significant increase in manufacturing cost.

Fin-double-gated junction field effect transistor

INTERNATIONAL BUSINESS MASHINES CORPORATION


An interface between memories having different write times is described. The interface includes a latch for capturing address and data information during a memory access by a processor of a first memory device. The interface also includes an index counter for providing frame management. The interface also includes a variable identity array logic for determining what data is to be written into a second memory device and address generation logic to determine where the data is to be stored in the second memory device. Additionally, the interface includes data validity logic to ensure that the data being written into the second memory device is valid. As a result, the processor can operate in substantially real time and can restore itself after detecting an event upset using the data stored in the second memory device.

Digital computers are used in many applications, including banking, industrial control processes, and other business systems. The digital computer is also used for controlling vehicles, such as aircraft, spacecraft, boats, and land vehicles. For example, automatic flight control systems for commercial and military aircraft use digital computers. In many applications, computations performed by these digital computers need to be performed in substantially "real time."
Digital computers may include numerous discrete semiconductor or integrated circuit bi-stable elements, generally referred to as latches. A latch is an electronic device that can switch between two stable states in response to low amplitude, high speed signals. Latches are utilized to construct much of the internal hardware of a digital computer, such as logic arrays, memories, registers, control circuits, counters, arithmetic and logic units, and so on.
Digital computers are subject to disturbances that may upset the digital circuitry, but not cause permanent physical damage. For instance, digital computers may operate at nanosecond and sub-nanosecond speeds causing rapidly changing electronic signals to flow through the computer circuits. These signals may generate electromagnetic fields, which may couple to circuits in the vicinity of the signals. While these signals can set latches into desired states, they can also set latches into undesired states. An erroneously set latch can compromise the data processed by the computer and, possibly, completely disrupt the data processing flow of the computer. In digital computer based systems, an error mode that does not result from component damage is typically referred to as a digital system upset or a soft fault.
Digital system upset can also result from spurious electromagnetic signals, such as those caused by lightning, which, for example, can be induced onto the internal electrical cables throughout an aircraft. Such transient signals can propagate to internal digital circuitry, setting latches into erroneous states. These transient signals represent a certain amount of energy. The changing state of the latch in this case is the result of a transfer of energy from the lightning induced transient signal to the electrical circuitry of the latch.
In addition to the energy transfer possible with a signal induced by a lightning event, other events can also provide enough energy transfer to change a latch state. For example, the intense fields associated with electromagnetic weapons, such as electromagnetic pulse (EMP) from a nuclear weapon detonation, high power microwave (HPM), or high-energy nuclear/atomic particles (from a variety of sources, e.g., atmospheric neutrons, cosmic radiation, nuclear weapon detonation, etc.), may deposit sufficient energy into bulk semiconductor material of the digital devices to set latches in erroneous states. Static discharges, power surge switching transients, and radar pulses may also produce spurious signals that can induce electrical transients on system lines and data buses, which in turn can propagate to internal digital circuitry, setting latches in erroneous states.
As described above, the nature of the events that can provide enough energy to change a latch state can be deterministic or stochastic. A latch change into an erroneous state due to such events is referred to as an event upset.
When unintended logic state changes occur, the system may not operate as intended. Energy from an event upset may compromise the data stored within the random access memory (RAM) area of the computer. A digital computer is susceptible to complete disruption if an incorrect result is stored in any of the memory elements associated with the digital computer. Safety-critical digital avionic computer applications, such as fly-by-wire or auto-pilot landings, cannot tolerate digital system upset due to event upsets. These safety-critical digital computers need to be designed to tolerate such event upsets without affecting the performance of the critical application.
One method to reduce the impact of event upsets on a digital computer is described in U.S. Pat. No. 6,163,480, which is assigned to the same assignee as the present application. The memory system for the digital computer includes a backup memory that includes hardened memory cells. Data that is critical for the dynamic restoration of the digital computer and to the operational state/status of the digital computer prior to the occurrence of a soft fault is stored in the backup memory. After an event upset, the digital computer can retrieve this data from the backup memory, which is not impacted by the event upset. Thus, the digital computer is restored to its operational state prior to the occurrence of the soft fault.
However, the backup memory typically has a write time that is slower than that of the main memory. Thus, an interface is needed between the main memory and the backup memory. Because computations within the digital computer for some applications need to be performed in substantially real time, it would be beneficial to provide an interface that allows critical data to be written to the backup memory without impacting the operation of the digital computer.

Interface for writing to memories having different write times


The present invention relates to an inter-vehicle communication apparatus and method using visible light communication. The inter-vehicle communication apparatus using visible light communication includes a spreading code application unit for applying a spreading code to transmission data desired to be transmitted, and a transmission unit for generating a transmission frame based on the transmission data to which the spreading code is applied, and transmitting the transmission frame via a lighting lamp of a vehicle. The transmission frame includes a preamble field required to synchronize the transmission frame, a data field required to transmit the transmission data, and a position field required to provide hopping information of the transmission data.

1. Technical Field
The present invention relates generally to an inter-vehicle communication apparatus and method using visible light communication and, more particularly, to an inter-vehicle communication apparatus and method using visible light communication, which reduce interference between pieces of data when performing wireless communication with another vehicle using lighting lamps for emitting visible light.
2. Description of the Related Art
Visible Light Communication (VLC) technology presented in Institute of Electrical and Electronics Engineers (IEEE) 802.15.7 VLC standards is communication technology for merging digital Light Emitting Diode (LED) illumination light with communication. Such VLC technology makes it possible to visibly verify whether communication has been performed, is harmless to a human body, and enables a physical security function or the like to be provided. In this case, an LED is advantageous in that it is capable of solving the problem of environmental destruction caused by mercury compared to existing lighting, that is, a fluorescent lamp and an incandescent lamp, and in that it has a long lifespan that is 10 times or more longer than that of the existing lighting and improves electrical efficiency by 90%. It can be considered that the creation of a communication environment using such a lighting infrastructure leads the way to communication that realizes the effects of economic benefits, the extension of multimedia communication services, and real-life lighting.
Recently, due to the exhaustion of Radio Frequency (RF) band frequencies, the possibility of confusion occurring between various types of wireless communication technologies, an increase in a demand for security of communication, and the arrival of a high-speed ubiquitous communication environment in 4G wireless technology, interest in optical wireless technology complementary to RF technology has increased, so that research into visible light communication using visible light LEDs has been conducted in various industrial fields.
As disclosed in Korean Patent No. 10-0908916, a method of transmitting data between vehicles using such visible light communication technology generally forms a network and transmits data over the network. However, this method is problematic in that respective vehicles have different speeds, and vehicles for transmitting and receiving signals are continuously changed, thus causing transmission and reception vehicles to be changed before a network is formed. Therefore, recently, instead of the method of forming a network and transmitting data, a broadcast method of allowing each vehicle to unilaterally transmit its own data has been proposed.
FIG. 1 is a diagram showing a method of transmitting data between vehicles that use visible light communication technology in a broadcast manner as described above.
Referring to FIG. 1, reception vehicle R receives data from vehicle A traveling in the same lane as that of vehicle R and vehicles B to E traveling in left and right lanes. When vehicles A to E simultaneously broadcast data, that is, when they transmit data in the same band at the same time, there is a very high probability that an error will occur in the data received by the reception vehicle. Therefore, there is required a technology for preventing interference from occurring between pieces of data on the reception vehicle even if vehicles A to E simultaneously broadcast data. Therefore, interference between pieces of data is prevented using a scheme that utilizes orthogonal codes between pieces of transmission data. In this case, when codes between pieces of transmission data are identical to each other, there is a very high probability that an error will occur in the data received by vehicle R. Further, there is a problem in that, when there is a difference in timing between pieces of transmission data, the orthogonality of orthogonal codes may be damaged.

Inter-vehicle communication apparatus and method using visible light communication

Electronics and Telecommunications Research Institute


A track roller assembly for a track-type machine such as an excavator or a tractor includes an outer surface with no fluid ports and an inner surface free from any fluids. The track roller includes a shaft resting on self-lubricated bushings, which include a substrate that has lubricating properties, such as a substrate that carries a solid lubricant. The track roller assembly also includes a collar on either side of the shaft, with a retention pin passing through the shaft and connecting the two collars.

Track rollers used on track-type machines such as excavators and tractors are subject to extremely high levels of stress and wear due to the conditions that track-type machines frequently operate under. While operating in extreme conditions, such as hilly and rocky terrains, track rollers are more prone to getting damaged. Consequently, such track rollers are plagued with relatively high service costs, short wear life and numerous other problems with their operation. One of such problems arises from the need to constantly keep the track rollers well lubricated. Operating track-type machines on difficult terrains frequently causes the leakage of lubrication fluid from the bearing assembly of the track roller into other areas of the track roller. This results in increased service costs for repairing the leak or replacing the entire track roller assembly. Other problems associated with track roller designs in the past include constructing assemblies with high part counts, complex manufacturing processes and handling liquid lubricants during construction.
U.S. Pat. No. 3,773,393 discusses an example of a liquid lubricated track roller assembly design. A pair of laterally spaced end caps receive a shaft and serve to support the shaft within a dead-end bore which is defined by a cylindrical inner wall and an end wall. A bearing assembly is mounted in the bore and interposed between the end cap and the shaft and includes a sleeve-type cylindrical bushing fixedly supported by the inner wall and a disc-type thrust washer secured to the end wall. A vertically extending channel formed within the end wall receives a liquid lubricant, such as oil that may be introduced to the roller assembly through a port. Although this patent teaches the use of bushings and thrust washers, it fails to address the longstanding problem of preventing lubricating fluid leaks that are prone to occur, such as under extreme operating conditions.

Track roller assembly and machine using same