Specimen Acceptance Devices and Attachable Disposable Assay Cartridges
20200122141 ยท 2020-04-23
Inventors
- Ramin Haghgooie (Arlington, AR, US)
- Robert Granier (Boston, MA, US)
- Kenneth T. Kotz (Auburndale, MA, US)
- Anne C. Petrofsky (Sudbury, MA, US)
Cpc classification
B01L2200/0631
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/16
PERFORMING OPERATIONS; TRANSPORTING
B01L2200/10
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/046
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/0864
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/0867
PERFORMING OPERATIONS; TRANSPORTING
B01L2300/044
PERFORMING OPERATIONS; TRANSPORTING
B01L3/502715
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
An apparatus includes a device for storing a liquid sample, in which the device has a sample acceptance well, one or more storage chambers, and one or more fluidic channels fluidly coupling the sample acceptance well to the one or more storage chambers. The apparatus also includes a well plate having a plate and multiple wells formed in the plate, in which the device and the well plate are configured to be attached to one another.
Claims
1.-46. (canceled)
47. A biological sample acceptance device comprising: a main body; a sample acceptance well positioned at a center axis of the main body; a plurality of storage chambers arranged around the sample acceptance well at a perimeter of the main body, wherein each storage chamber is accessible from an exterior of the main body through a seal, wherein the plurality of storage chambers are fluidically coupled to the sample acceptance well; and a plurality of vents coupled to the plurality of storage chambers, respectively, wherein each vent is open to an exterior of the main body, wherein each vent comprises a corresponding hydrophobic valve, membrane or stop that allows gasses, but not liquids, to outflow from the storage chamber to which the vent is coupled, wherein at least one storage chamber of the plurality of storage chambers comprises a reagent, a sample separation material or a combination thereof.
48. The biological sample acceptance device of claim 47, wherein the device is configured to be rotated about the center axis such that a fluid sample within the sample acceptance well is subject to centrifugal forces that cause the fluid sample to be distributed to the plurality of storage chambers.
49. The device of claim 47 comprising a needle fluidically coupled to the sample acceptance well.
50. The device of claim 47, comprising a plurality of fluidic channels extending outwardly from the sample acceptance well through the main body and toward the perimeter of the main body, the plurality of fluidic channels allowing fluidic coupling of the sample acceptance well to the plurality of storage chambers, respectively.
51. An apparatus for use with a specimen analysis system, the device comprising: at least one well-plate, the at least one well-plate comprising a plurality of wells; and a sample acceptance device, wherein the sample acceptance device comprises a main body, a sample acceptance well in the main body, a plurality of storage chambers in the main body and arranged around the sample acceptance well, wherein each storage chamber is accessible from an exterior of the main body through a seal, a plurality of fluidic channels extending outwardly from the sample acceptance well through the main body and allowing fluidic coupling of the sample acceptance well to the plurality of storage chambers, wherein each of the sample acceptance well and the plurality of storage chambers are fluidically isolated from the plurality of wells of the at least one well-plate.
52. The apparatus of claim 51, wherein the at least one well-plate and the sample acceptance device are combined into a cartridge for use with the specimen analysis system.
53. The apparatus of claim 51 further comprising at least one encoder element configured to be read by the specimen analysis system, the at least one encoder element encoding information about fluid samples stored in the sample acceptance device, reagents stored in the at least one well-plate, an assay to be performed using the cartridge, volumes of fluid samples to be transferred among the apparatus, the plurality of wells of the at least one well-plate into which fluid samples are to be transferred, or combinations thereof.
54. The apparatus of claim 51, wherein each well of the plurality of wells is covered by a corresponding foil laminate that seals the well.
55. The apparatus of claim 51, further comprising a bottom layer, wherein the at least one well-plate and the sample acceptance device are on the bottom layer to provide a cartridge for use with the specimen analysis system.
56. The apparatus of claim 55, wherein the bottom layer and the at least one well-plate are attached to one another.
57. The apparatus cartridge of claim 55, wherein the at least one well-plate is attached to the bottom layer through a fastener or adhesive.
58. The apparatus of claim 51, wherein the sample acceptance device is configured to interlock with the at least one well-plate.
59. The apparatus of claim 51 comprising a needle fluidically coupled to the sample acceptance well.
60. The apparatus of claim 51, wherein the sample acceptance device is configured to transfer fluid from the sample acceptance well through the plurality of fluidic channels to the plurality of storage chambers upon application of a pneumatic pressure to the sample acceptance well.
61. The apparatus of claim 51, wherein the apparatus comprises two well-plates, and a first well-plate is loaded with a first assay panel and a second well-plate is loaded with a second assay panel different from the first assay panel.
62. An apparatus for use with a specimen analysis system, the modifiable cartridge comprising: a plurality of removable modular well-plates; and a removable sample acceptance device, the sample acceptance device comprising a sample acceptance well, a plurality of storage chambers, and a plurality of fluidic channels coupling the sample acceptance well to the plurality of storage chambers, respectively, wherein each of the sample acceptance well and the plurality of storage chambers are fluidically isolated from the plurality of well-plates.
63. The apparatus of claim 62 comprising a bottom layer, wherein the at least one well-plate and the sample acceptance device are on the bottom layer to provide a cartridge for use with the sample analysis system.
64. The apparatus of claim 63, wherein the bottom layer and the plurality of removable modular well-plates are attached to one another.
65. The apparatus of claim 63, wherein the plurality of removable modular well-plates are attached to the bottom layer through a fastener or adhesive.
66. The apparatus of claim 64, wherein the plurality of removable modular well-plates are configured to interlock with one another.
67. The apparatus of claim 66, wherein the removable sample acceptance device is configured to interlock with one or more of the plurality of removable modular well-plates.
68. The apparatus of claim 62, wherein each well-plate of the plurality of well-plates is fluidically isolated from one another.
69. The apparatus of claim 62, wherein at least two well-plates of the plurality of well-plates have different sizes.
70. The apparatus of claim 62, wherein at least two well-plates of the plurality of well-plates are loaded with different assay panels.
71. The apparatus of claim 62, wherein one or more wells of at least one well-plate is sealed by a corresponding foil laminate.
72. The apparatus of claim 62 comprising a needle fluidically coupled to the sample acceptance well.
73. The apparatus of claim 62, wherein the sample acceptance device is configured to transfer fluid from the sample acceptance well through the plurality of fluidic channels to the plurality of storage chambers upon application of a pneumatic pressure to the sample acceptance device or application of a vacuum to the sample acceptance device.
74. A method for preparing a liquid sample for analysis, the method comprising: loading the liquid sample into a sample acceptance well of a device, wherein the device comprises a main body, the sample acceptance well positioned at a center axis of the main body, a plurality of storage chambers arranged around the sample acceptance well at a perimeter of the main body, wherein each storage chamber of the plurality of storage chambers is accessible from an exterior of the main body through a seal and wherein the plurality of storage chamber are fluidically coupled to the sample acceptance well, and a plurality of vents coupled to the plurality of storage chambers, respectively, wherein each vent is open to an exterior of the main body, wherein each vent comprises a corresponding hydrophobic valve, membrane or stop that allows gasses, but not liquids, to outflow from the storage chamber to which the vent is coupled; and causing the liquid sample to flow from the sample acceptance well into the plurality of storage chambers.
75. The method of claim 74, further comprising combining the device with at least one well plate comprising a plurality of wells to provide a cartridge, wherein the sample acceptance well, and the plurality of storage chambers are fluidically isolated from the plurality of wells.
76. The method of claim 74, wherein the device comprises a plurality of fluidic channels extending outwardly from the sample acceptance well through the main body and toward the perimeter of the main body, the plurality of fluidic channels allowing fluidic coupling of the sample acceptance well to the plurality of storage chambers, respectively, and wherein the liquid sample flows from the sample acceptance well through the plurality of fluidic channels and into the plurality of storage chambers, respectively.
77. The method of claim 74, further comprising transferring the liquid sample from at least one of the plurality of storage chambers to at least one well of the plurality of wells.
78. The method of claim 77, wherein the at least one well is preloaded with a reagent.
79. The method of claim 77, wherein transferring the liquid sample from the at least one of the plurality of storage chambers to the at least one well of the plurality of wells comprises transferring the liquid sample by pipette from the at least one of the plurality of storage chambers to the at least one well of the plurality of wells.
80. The method of claim 74, comprising: transferring the cartridge to a fluid analyzer system; and analyzing one or more chemical reactions that occur in the one or more wells of the well-plate subsequent to transferring the liquid sample to the at least one well of the plurality of wells.
81. The method of claim 75, wherein combining the device with the well plate to provide the cartridge comprises attaching the device and the well plate to a bottom layer.
82. The method of claim 75, wherein combining the device with the well plate to provide the cartridge comprises interlocking the well plate with the device.
83. The method of claim 74, further comprising: transferring the device to a fluid analyzer system; transferring the liquid sample from at least one of the plurality of storage chambers to at least one well of a well-plate; and analyzing one or more chemical reactions that occur in the at least one well of the well-plate subsequent to transferring the liquid sample to the at least one well.
84. The method of claim 74, wherein at least one storage chamber of the plurality of storage chambers comprises a reagent, a sample separation material or a combination thereof.
85. The method of claim 74, wherein causing the liquid sample to flow from the sample acceptance well into the plurality of storage chambers comprises applying a centrifugal force to the liquid sample.
86. The method of claim 74, wherein causing the liquid sample to flow from the sample acceptance well into the plurality of storage chambers comprises using air pressure to cause the liquid sample to flow into the plurality of storage chambers.
87. The method of claim 74, wherein causing the liquid sample to flow from the sample acceptance well into the plurality of storage chambers comprises creating air pressure to cause the liquid sample to flow into the plurality of storage chambers.
88. The method of claim 74, wherein causing the liquid sample to flow from the sample acceptance well into the plurality of storage chambers comprises creating a vacuum pressure to cause the liquid sample to flow into the plurality of storage chambers.
89. The method of claim 74, further comprising: transferring the cartridge to a fluid analyzer system; and analyzing one or more chemical reactions that occur with the liquid sample.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
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[0058] As shown in the example of
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[0060] Once the specimen sample has been loaded into the main sample collection well 112 and the lid 104 of the device 100 is closed, the plunger 106 is depressed. The main sample collection well 112 is fluidly coupled to the one or more sample chambers 108 using microfluidic channels formed in the interior of the main body portion 102. Accordingly, as the plunger is depressed (see
[0061] In some implementations, the specimen sample is filtered before it enters the sample chamber 108. For example, the microfluidic channels of the device 100 that are coupled to the main well 112 may deliver the specimen sample to a filter (e.g., membrane or a gel) prior to reaching the sample chamber 108. As the specimen passes through the filter component, the desired portion of the specimen (e.g., plasma or serum) is separated and passed onto the sub-chamber 108 while the undesired portion of the specimen is held in the filter or redirected to a waste chamber. Example gels include serum separator or plasma separator available from Becton Dickinson. These gels form physical barriers between the serum or plasma and blood cells.
[0062] The divided specimen samples then are stored in the sample chambers 108 for a period of time. For instance, if kept in an environment set at about room temperature (i.e., between about 20 and 26 C.), blood samples may be stored in the sub-chambers 108 for up to about hour before changes in hematologic parameters make the sample unusable for further analysis and processing. In some implementations, however, the storage time may be extended beyond hour, for instance up to 12 hours, 24 hours, or even 48 hours using refrigeration of the device.
[0063] When it is time for analyzing the specimen samples, the device 100 can be secured to a disposable assay cartridge 250. The cartridge 250 may include a receptacle region 252 for receiving the sample acquisition device 100. In some implementations, the receptacle region 252 and device 100 are designed so that the device 100 snaps into place on the receptacle region 252 and is held securely to the cartridge 250. For instance, the receptacle region 252 and the device may be formed to have a tongue/groove design in which one or more protrusions (i.e., the tongue) formed on either the receptacle region 252 or the device 100 fits into a corresponding slot or other opening (i.e., the groove) formed in the opposing device 100 or the receptacle region 252, such that the two components (cartridge 250 and device 100) lock in place together (e.g., through friction or the shape of the tongue and groove). The interlocking elements slide into place and can be made secure as the two pieces are positioned together in a similar manner to the tongue/groove locking systems used in laminate flooring.
[0064] The cartridge 250 may further include multiple wells that are either empty or pre-loaded with one or more different reagents. After joining together, the disposable cartridge 250 and device 100 then are delivered to an analyzer system where analysis of the specimen samples occurs. For instance, the analyzer may perform chemistry, hematology, or immunoassays on the specimen sample. In particular, portions of the specimen sample are transferred from one or more of the sample chambers 108 to one or more of the wells in the cartridge for performing a reaction with the reagents in the well. The product of the reactions then is investigated by the analyzer system, described in more detail below. In some implementations, the analyzer system can receive the cartridge 250 and the device 100 separately. For instance, the analyzer system can include a receptacle or slot to receive the cartridge 250 and a separate receptacle or slot to receive the device 100.
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[0066] When it is time for analyzing the specimen samples stored in the device 100, the device 100 is secured to the disposable assay cartridge 250. Since the device 100 includes the needle guard 304, a hole 306 may be formed in a bottom surface of the receptacle region 252 for receiving the needle guard 304 and holding the device 100 in place on the cartridge 250. Again, the device and cartridge may also include a tongue/groove design for fixing the device 100 to the cartridge 250 in a similar manner as to that described with respect to the embodiment of
[0067] Other embodiments of the device 100 are also possible. For instance, in some implementations, the specimen samples are delivered to the sample chambers 108 using centrifugal forces instead of pressure created with the plunger. That is, the device may have a generally circular footprint, with the main sample collection well 112 formed at the center of the device 100, and the sub-chambers formed at the outer perimeter of the device. After loading a specimen sample in the main sample collection well 112, the device 100 then may be rotated about a central axis that extends through the main sample collection well 112, such that the specimen experiences centrifugal forces splitting the specimen into the one or more internal microfluidic channels that connect the main sample collection 112 well to the sample chambers 108. Again, the device may include filters, such as membranes or gels, which separate the specimen into desired and undesired portions, with the desired portions passing into the sub-chambers. In another example, the sample specimen may be loaded into the main collection well through a re-sealable septum (e.g., on a bottom surface of the device in a similar location as the needle 302). For instance, the re-sealable septum may include a rubber seal that is pierced using a needle or pipette. The specimen then is injected into the main sample collection well. When the pipette or needle is withdrawn, the septum naturally re-seals the hole created by injection. Once the specimen is loaded into the main sample collection well, the specimen may be distributed to the sample chambers 108 using a vacuum force (e.g., created with the plunger such as the plunger 106 located on a top surface of the device opposite to the surface in which the septum is arranged or through a vacuum force stored within the device) or using centrifugal forces as described above.
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[0073] The first laminate layer 702 is designed to include openings that correspond to fluidic channels for distributing the sample specimen to a separation membrane, as well as openings that correspond to fluidic channels to vent air from the sample chambers. The second laminate layer 704 includes foil seals for sealing the top of the sample chambers. The foil seals may be formed from a material such as aluminum.
[0074] The second laminate layer 704 also may include hydrophobic valves or membranes that allow air to vent from the fluidic channels and chambers of the device when the sample chambers are filled with the specimen sample. The hydrophobic membranes may be formed from, for example, a porous polytetrafluoroethylene (PTFE) material such as the hydrophobic Aervent membranes available from Millipore.
[0075] The third laminate layer 706 is configured to include access holes through which a user can access the sample specimen. When the device is fully assembled, the access holes are covered by the foil seals of layer 704.
[0076] The fourth laminate layer 708 includes an adhesive (e.g., a thin glue layer or adhesive tape) that seals around a perimeter of a top surface of the separation membrane.
[0077] The fifth laminate layer 710 includes the separation membrane, which is used, for blood specimens, to separate the plasma from the blood.
[0078] The sixth laminate layer 712 includes another adhesive layer (e.g., thin glue or adhesive tape) that seals around a perimeter of a bottom surface of the separation membrane. As shown in
[0079] The laminate layers assemble into a stack and are affixed to a top surface of a main plate 714. The main plate 714 is a thick structure relative to the layers in the laminate stack. The main plate 714 also can be formed from a plastic, such as PMMA, or other material that is bio-compatible with the specimen sample. For example, the main plate 714 can be formed from glass. The main plate 714 includes the main sample acceptance well, the sample chambers, and the plasma collection channel. Each of the acceptance well, sample chambers and plasma collection channel extends through the thickness of the main plate 714. A bottom laminate layer 716 is positioned beneath the main plate 714 and includes specimen distribution channels for transporting the specimen between the chambers, the acceptance well and the plasma collection channel. Finally, an air vent/septum seat layer 718 is located at the bottom of the device. The septum seat layer 718 includes an opening that leads to a re-sealable septum or hydrophobic vent from which air can escape from the device or, using a vacuum, air can be withdrawn from the device. When fully assembled, the stack of laminate layers, the main plate 714, the bottom laminate layer 716, and the septum seat 718 may be secured together using, for example, screws that extend through each layer of the device. Alternatively, the layers may include an adhesive that allows each layer to be affixed to the next adjacent layer in the device.
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[0081] In one example, the sample acceptance devices shown in
[0082] The sample acceptance device is intended to provide a simple and low cost device for storing and keeping specimen samples stable until it is time to perform analysis, such as a hematology panel, a chemistry panel and/or an immunoassay panel, including, for example, a complete blood count (CBC), a basic metabolic panel (BMP) assay, a comprehensive metabolic panel (CMP) assay, a hepatic assay, an amylase/lipase assay, a cardiac assay, and/or a toxicology assay. Because the sample acquisition device does not include the reagents used in performing the sample analyses, it does not need to be kept refrigerated prior to use and can therefore be stored close to the patient/point-of-care.
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[0084] As shown in
[0085] The flexibility of the well-plate format allows the cartridge to interface with a pipetting system for delivery of the sample from the sample acquisition device 1000 to any one or more of the wells 902 of the cartridge 900. Before transferring portions of the sample specimen from the device 1000 to the wells 902 of the cartridge 900, the device 1000 can be secured to the cartridge 900. As explained above with respect to
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[0087] The main body portion 1102 of the disposable cartridge 900 may be formed of a bio-compatible material, such as PMMA or glass, in which the wells 902 are formed. The depth of the wells 902 extends entirely through a thickness of the main body portion 1102. The wells 902 can be designed to hold different volumes of fluid including for example between about 10 and 500 microliters. The wells 902 may be designed to hold other volumes as well. Depending on the assays to be performed, the wells may be pre-loaded with one or more different reagents. For example, the wells may be pre-loaded with one or more of a hemoglobin reagent, a glucose reagent, an alkaline phosphatase (ALP) reagent, a white blood cell reagent, a red blood cell reagent, a platelet (PLT) reagent, or a basophil (BASO) reagent. Other reagents may be used as well.
[0088] Examples of the different assay panels for which the cartridges may be designed include, but are not limited to, comprises a complete blood count (CBC) assay, a basic metabolic panel (BMP) assay, a comprehensive metabolic panel (CMP) assay, a hepatic assay, an amylase/lipase assay, a cardiac assay, a toxicology assay, among others.
[0089] The bottom layer 1104 includes a laminate film (e.g., plastic) with multiple access holes 1108 that are covered in foil to contain the reagents until it is time to remove the product from the wells 902. The top layer 1100, the main body portion 1102, and the bottom layer 1104 may be assembled together using, for example, screws or adhesives. A fully assembled cartridge may have, for example, the following overall dimensions: a width of between about 2 to 4 inches, a length of between about 4 to 10 inches, and a thickness of between about 0.25-0.75 inches. Other dimensions may be used as well.
[0090] In some implementations, the cartridge 900 can be formed in a modular manner. That is, the cartridge 900 can be made up of multiple sub-cartridges that are snapped together either by the user or during assembly. The sub-cartridges each contain different panels of assays (i.e., each section may include wells containing different reagents depending on the assay panel to be performed) so that when they are combined the final cartridge contains multiple panels of tests. For instance, a comprehensive metabolic panel (CMP) sub-cartridge could be snapped together with a complete blood count (CBC) sub-cartridge to produce a finished well-plate cartridge. Alternatively, the sub-cartridge could be replaced with a Cardiac Event sub-cartridge to create a different panel of assays.
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[0092] Once the proper cartridge has been selected for the desired assay panel(s) and the cartridge and sample acceptance device have been attached to one another, the combined cartridge and sample acceptance device is delivered to a sample analyzer, which transfers portions of the sample from the sample acceptance device to the wells in the cartridge, and then analyzes the chemical reactions and products that form.
[0093] The analyzer system 1404 may perform this transfer automatically using an automated pipetting system, where a needle or pipette punctures the seals on the chambers in the sample acceptance device and withdraws a defined aliquot of the specimen. The needle or pipette then is repositioned over a well in the cartridge, where the needle or pipette subsequently punctures the seal covering the reagent in the well and delivers the specimen. Once the time for the desired reaction has elapsed, the analyzer system may extract any product or resulting fluid sample from the wells to which the specimen had been transferred. The samples are extracted on the bottom side of the cartridge (opposite to the side in which the specimen was introduced into the wells), again using a needle or pipette, that pierces the foil isolating the samples. The retrieved samples are sent through the analyzer system, which includes an electronic processor for subsequently performing one or more measurements on the obtained samples (bottom middle figure). The measurements may include photometric measurements, such as those described in WO 2014/078785, the entire disclosure of which is incorporated herein by reference in its entirety.
[0094] Alternatively, or in addition, the measurements may include cytometric measurements (e.g., cell counting or phenotyping), immune-assays (e.g., ELISA), and/or electrochemical measurements. The analyzer system 1404 may be configured to read the machine readable code located on the sample acceptance device and the disposable cartridge (e.g., on labels on the device and cartridge) such that the analyzer system can automatically determine what specimens are provided in the acceptance device, to which wells of the cartridge the specimens need to be transferred, the volume of the specimen that needs to be transferred, and the tests to be performed for the desired assay panel. The output of the analysis may then be delivered to a user, e.g., using an electronic display and/or may be stored in memory of the analyzer system (see bottom right figure).
[0095] As explained above, however, the cartridge and sample acceptor device to not necessarily need to be coupled together when provided to the analyzer system. For example, in some implementations, the analyzer system may include separate receptacles or openings in different regions of the analyzer system for receiving the cartridge and the sample acceptor device. The analyzer 1404 may still function in the same manner as described herein, in which the analyzer 1404 may automatically transfer portions of the specimen from the sample acceptance device into one or more of the wells of the cartridge, extract any product or resulting fluid sample from the wells to which the specimen had been transferred, and subsequently perform one or more measurements on the obtained samples.
[0096] In general, any of the analysis methods described herein in the analyzer system, including determining information about a specimen sample based on the products and/or reactions of the sample with reagents in the disposable cartridge, can be implemented in computer hardware or software, or a combination of both. For example, in some embodiments, the electronic processors can be installed in a computer as part of an analyzer systems and can be configured to perform analysis of measurements performed on the specimen samples. The analyses can be implemented in computer programs using standard programming techniques following the methods described herein. Program code is applied to input data (e.g., voltages from photo-sensors or currents from electrodes of the analyzer system) to perform the analysis and generate output information (e.g., slopes of voltage/current vs. time, peak voltage or current amplitude and widths, cell counts, and blood chemistry levels such as glucose, protein, bilirubin levels, among others). The output information is applied to one or more output devices such as a display monitor. Each program may be implemented in a high level procedural or object oriented programming language to communicate with a computer system. However, the programs can be implemented in assembly or machine language, if desired. In any case, the language can be a compiled or interpreted language. Moreover, the program can run on dedicated integrated circuits preprogrammed for that purpose.
[0097] Each such computer program is preferably stored on a tangible storage medium or device (e.g., ROM or magnetic diskette) readable by a general or special purpose programmable computer, for configuring and operating the computer when the storage media or device is read by the computer to perform the procedures described herein. The computer program can also reside in cache or main memory during program execution. The analysis methods can also be implemented as a tangible computer-readable storage medium, configured with a computer program, where the storage medium so configured causes a computer to operate in a specific and predefined manner to perform the functions described herein.
OTHER EMBODIMENTS
[0098] A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Other embodiments are within the scope of the following claims.