Abstract:
An improved method and apparatus for transporting a syringe containing radioactive material that provides many advantages, including the safe enclosure of the syringe both before and after use, which reduces the possibility of contamination of the radiopharmaceutical pig. The present invention also provides a radiopharmaceutical pig that eliminates the need for a protective plastic outer shell and has a convenient grip. Finally, the present invention allows the user to readily determine if a syringe within a closed sharps container is full or spent without handling the container.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to shielded containers for the transportation of radioactive materials and, more particularly, to shielded containers for the transportation of syringes containing radioactive drugs, or radiopharmaceuticals. 
     In the nuclear medicine industry, it is well known for pharmacies to deliver syringes containing radioactive drugs to hospitals for injection into a patient. One use for these types of drugs is for the x-ray or other imaging of internal human organs. Pharmacies receive prescription orders and deliver the corresponding radioactive drugs to nearby hospitals for use. Each prescription is individually filled, and each dose of radioactive drug is packaged in a syringe intended for a specific patient. 
     Radioactive drugs must be carefully handled. Therefore syringes containing such drugs are delivered inside containers offering some degree of radiation shielding. Furthermore, government regulations require syringes to be disposed of in a disposal container that shields others from the risk of injury posed by their sharp, biologically-contaminated hypodermic needles. Such a container, generally referred to herein as a “sharps” container, typically has an inner cavity or chamber that can hold one or more syringes. 
     One type of conventional delivery container currently used for the delivery of syringes containing radioactive drugs is known as a radiopharmaceutical pig. The radiopharmaceutical pig has a shielded inner chamber suitable for enclosing a syringe that is itself held inside of a sharps container. In particular, the chamber is lined with elemental lead to shield people from the radioactive drug in the syringe. The exterior of the radiopharmaceutical pig is a plastic polystyrene shell. The sharps container has an insert and a cap that can be engaged by two snaps that fit into two aligned slots formed on the insert. 
     One conventional method for delivering the radioactive syringe uses the devices described above. In particular, at the pharmacy, a sharps container insert is placed in the radiopharmaceutical pig. The syringe is loaded with the required dose of a radioactive drug is placed in the insert, which is nested in the chamber of the radiopharmaceutical pig. The radiopharmaceutical pig is then closed and delivered to the hospital, whereupon the pig is disassembled and the syringe is used according to other, well known, safety standards. 
     After the dose is injected into the patient, the syringe is referred to as “spent,” but generally contains a small amount of residual radioactive drug. In addition to the radioactive contamination, the hypodermic needle of the spent syringe is biologically contaminated from contact with the patient. The spent syringe may then be placed back into the sharps insert and the cap may then be placed on the housing to hold the spent syringe within the sharps container. The radiopharmaceutical pig is reassembled and taken to a disposal area, which may or may not be at the pharmacy. 
     While the previously discussed radiopharmaceutical pig and sharps container are generally effective, under certain conditions there may be drawbacks associated with such devices. One such drawback is that the snaps on the sharps container cap must be aligned with the slots on the insert in order to attach the cap to the insert. Thus, it may be difficult or more time consuming for a healthcare worker to align the snaps with the slots to attach the cap to the insert. 
     The conventional cap also is difficult to remove from the insert after it has been attached to the insert. Thus, the cap typically is not installed on the insert at the pharmacy, prior to its delivery to the hospital. Because the insert is not capped, there is a risk that the loaded syringe could leak and that the leaked radioactive drug could escape from the insert if the pig is tilted or inverted. If such contamination occurs, cleaning and disinfecting of the pig will require additional manpower and expense. Such a process is expensive and, therefore, undesirable. 
     Yet another drawback is related to the difficulty of determining if the syringe in the sharps container is spent or not. If the insert is transparent, the sharps container must be removed from the radiopharmaceutical pig in order for a worker to look through the insert at the syringe. If the insert is not transparent, the sharps container may have to be disassembled to view the syringe. Therefore, a worker may expend excess time in determining whether or not the syringe in the sharps container is spent. 
     Still another drawback is associated with lead shielding of the radiopharmaceutical pig. The soft nature of lead is not well suited to form threaded engagements, so the pig has two plastic outer shells that threadedly engage each other. The outer shells could crack or break upon impact, thereby rendering the pig unusable. In addition, a cracked pig shell could cause a worker to be exposed to sharp edges formed by the cracked plastic. The lead shielding also is bulky, resulting in a large-sized radiopharmaceutical pig. 
     Accordingly, there exists a need for an improved radiopharmaceutical pig and/or sharps container that alleviates one or more of the drawbacks identified above. 
     SUMMARY OF THE INVENTION 
     The present invention resides in an improved method and apparatus for transporting a syringe containing radioactive material that provides manly advantages, including the safe enclosure of the syringe both before and after use, reduces the possibility of contamination of the radiopharmaceutical pig. The present invention also provides a radiopharmaceutical pig that eliminates the need for a protective plastic outer shell. Finally, the present invention allows the user to readily determine if a syringe within a closed sharps container is full or spent without handling the container. 
     Particularly, and by way of example only, one embodiment of the invention is a transportation container for a syringe containing a radioactive material. The transportation container includes a body and a grip. The body has an upper end, a lower end, and an interior surface defining an internal chamber sized to enclose the syringe. The internal chamber is surrounded by radiation resistant material. The grip is located on the upper end of the body and has an exterior surface defining an enlarged area to be grasped by the worker. 
     The container may have a grip that extends around the upper end of the body and the grip may be a separate piece attached by frictional engagement with the upper end of the body. In further details, an enlarged base may be provided on the lower end of the body. The base may have an enlarged bottom end to stabilize the container as it sits on a surface. The transportation container may also include a sharps container sized to enclose the syringe. The internal chamber of the body is sized to enclose the sharps container. The grip may be a separate piece or can be integrally formed into the body. The body of the container may be made of tungsten. 
     In yet another independent and separate embodiment, a transportation container for a syringe containing a radioactive material is provided. The transportation container includes a body having an upper end, a lower end, and an interior surface defining an internal chamber sized to enclose the syringe. The internal chamber is surrounded by radiation resistant material. Also included is a sharps container having a cap and a housing sized to cooperatively enclose the syringe and fit into the chamber of the body. The cap has a closed end and a mating end and the housing has a closed end and a mating end configured to releasably engage the mating end of the cap without requiring precise alignment of the cap with the housing. In this manner, healthcare workers can easily and conveniently attach and remove the cap without bothering to precisely align any clips or snaps. Further detailed features Stay include providing the cap of the sharps container with a circumferential ridge located around in its mating end and/or providing the housing of the sharps container with a circumferential ridge located around its mating end. 
     In yet another independent and separate embodiment, a transportation container for a syringe containing a radioactive material is provided. This transportation container is made up of multiple pieces of radiation-resistant material, at least one of which has a reduced diameter so as to reduce costs of manufacture and/or shipping. 
     Yet another independent and separate embodiment provides a method of transporting a syringe containing a radioactive material to a location for use and confining the syringe within a protective container having a housing that can mate with one of two different-sized caps. The protective container is sized to be enclosed in a radiopharmaceutical pig. The method includes inserting the syringe into the housing of the protective container and attaching one cap to the housing of the protective container to enclose the syringe therein. Next, the radiopharmaceutical pig is assembled to enclose the protective container enclosing the syringe. The radiopharmaceutical pig is transported to the location for use and disassembled whereupon the first cap is removed from the protective container. Next, at least some of the radioactive material is discharged from the syringe, resulting in a spent syringe. The spent syringe is then placed in the housing of the disposal container and the other cap is attached to the housing to enclose the spent syringe therein. Optionally, the disposal container may then be placed within the radiopharmaceutical pig, for transport to a disposal area without exposing the spent syringe. 
     Finally, yet another independent and separate embodiment provides a method of handling a syringe containing a radioactive material. The method utilizes a protective container having a housing and a cap and includes inserting the syringe into the housing of the protective container and then attaching the cap to the housing of the protective container to enclose the syringe therein, without the need for precisely aligning the cap with the housing. Optionally, the method may also include removing the cap from the housing without damaging either by only moving the cap away from the housing. Because precise alignment of the cap and housing is not needed, it is more convenient for health care workers to use the above method. 
     Other features and advantages of the present invention will become apparent from the following description of the preferred embodiment, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The following drawings illustrate the invention. In such drawings. 
     FIG. 1 is an exploded perspective view of the container according to the invention, shown with a syringe containing radioactive material; 
     FIG. 2 is a cross-sectional view of the container of FIG. 1; 
     FIG. 3 is a cross-sectional view of the inner container of the container of FIG. 2; 
     FIG. 4 is a cross-sectional view of the container of FIG. 1, shown holding a spent syringe and a smaller cap on the inner container; 
     FIG. 5 is a cross-sectional view of the inner container of the container of FIG. 4; and 
     FIG. 6 is a detailed view of the container of FIG. 3, taken about lines  6 — 6 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in the exemplary drawings, the preferred embodiment of the present invention comprises a radiopharmaceutical pig  10  and a sharps container  12  for a syringe  14  holding a radioactive drug. The syringe holding the radioactive drug fits within the sharps container, which, in turn, fits within the radiopharmacetcal pig. The sharps container may be designed to meet U.S. government regulations, such as 29 C.F.R. §1910.1030, for protective containers that house materials having biologically contaminated sharp edges. However, the sharps container design could be modified depending on a particular application. 
     FIGS. 1,  2 , and  4  show the relationship between the components of the radiopharmaceutical pig  10  and the sharps container  12 . The radiopharmaceutical pig has a tubular upper shield  16  that screws onto a tubular lower shield  18 . the sharps container nests within the upper shield and lower shield. Likewise, the sharps is comprised of a lower insert  20  and an upper cap  22  that cooperatively enclose the syringe  14 . 
     The upper shield  16  of the radiopharmaceutical pig  10  has a generally tubular shape and has a closed end  24  and an open end  26 . The lower shield  18  has a generally tubular shape and has a closed end  28  and an open end  30 . Both shields have internal cavities  32  and  34  sized to accept at least a portion of the sharps container  12 . The upper and lower shields are preferably constructed of tungsten, but any radiation-resistant material may be used, depending on the desired application. 
     The open end  26  of the upper shield  16  connects to the open end  30  of the lower shield  18  when the radiopharmaceutical pig  10  is assembled. Referring now to FIGS. 1,  2 ,  4 , and  6 , the upper shield of the radiopharmaceutical pig has a main body portion  36  and a flanged end portion  38 . The main body portion is tubular and has a threaded area  40  on the external surface of its lower end  42 . Preferably, the flanged end portion has two open ends  44  and  46  and a passageway  50  therebetween with an inside diameter at least as large as the external diameter of the main body portion. The upper area of the internal passageway of the flanged end portion has threads  52  configured to engage the threads on the main body portion. A waterproof adhesive or sealant can be put on or between these threads to provide for a permanent, secure connection between the main body portion and the flanged end portion. (Other means of attachment could be used, such as welding or other mechanical fasteners, or the flanged end portion may be integrally formed to the main body portion. The lower portion of the passageway of the flanged body portion also has threads  54  configured to engage external threads  56  on the open end  30  of the lower shield, as described below. The flanged end portion may also have wrench flats  59  for use in preventing the rolling of the radiopharmaceutical pig and/or tightening the upper shield to the lower shield. Lastly, the bottom inside edge of the flanged end portion defines a channel  58  to accommodate an O-ring  60  to provide a seal between the upper and lower shields. 
     Finally, a tubular plastic grip  62  is mounted on the closed end  24  of the upper shield  16 . The grip may be mounted by press fit, with adhesive, or mechanical fasteners. The grip has external channels  64  to facilitate gripping of the container by users. The grip also functions as a shield to protect the upper shield from impacts that could crack or damage it. The tubular grip may be made from plastic or rubber, including PVC material. 
     The lower shield  18  preferably is comprised of three pieces: a tubular body  66 , an upper circular flange  68 , and a lower end-cap  70 . The tubular body has openings on both ends  72  and  74  and a passageway  76  therebetween sized to accept at least a portion of the syringe  14  and/or the sharps container  12  therein. The tubular body has an upper end  72  with a circular wall  78  extending upwardly therefrom to contact an upper ridge  120  on the sharps container insert  20 , as will be described below. The upper end of the tubular body also has external threads  82  configured to engage threads  84  on the inside surface of the circular flange. The cross-section of the circular flange is “L” shaped and may have a circular indentation  86  to accept a portion of the O ring  60  therein. The upper portion of the circular flange  8  has external threads  56  configured to engage the threads  54  on the inside of the flanged end portion  38  of the upper shield  16 . Wrench flats  87  may be formed on the outside edge of the flange. When assembled, the lower end  26  of the flanged end portion abuts an upper surface  88  located on the horizontal leg of the “L” shaped circular flange. The threads described herein may be connected with adhesive or other mechanical or chemical ways of mounting the components together may be used, as is appropriate for a particular application. 
     The end cap  70  forming the lower portion of the lower shield  18  is tubular and has a shape similar to the body portion  36  of the upper shield  16 . The end cap defines an internal cavity  90  having diameter lesser than that of the lower body  66  of the lower shield. The lower end of the passageway  76  in the body portion has internal threads  92  configured to engage external threads  94  located on the upper portion of the end cap. The cavity in the end cap may be smaller because it may only need to accommodate the narrower portions of the syringe  14 . Because less radiation-resistant material is needed to manufacture the end cap, it is believed to be more cost effective to form the lower shield from the body and the end cap, as compared to a one-piece shield having a uniform diameter throughout its entire length. 
     A tubular plastic base  96  is mounted on the lower end of the lower shield  18 . The base may be made of the same material as the plastic grip  62  mounted on the upper shield  16 . Channels  98  are formed in the outer surface of the base to facilitate gripping by healthcare workers for the assembly and dis-assembly of the radiopharmaceutical pig  10 . The base may be mounted to the lower shield by a press fit, with adhesive, or mechanical fasteners. The base also protects the lower shield from impacts that could cause cracks or other damage. The base has an enlarged lower end  100  sized to stabilize the radiopharmaceutical pig  10  when it is placed on a table top or other work surface. 
     The syringe  14  has a generally tubular body  102  with a flanged base  104 , a hypodermic needle  106 , a cap  108 , and a plunger  110 . The body and needle of the syringe nest within the sharps container housing  20 . The plunger fits within the upper shield  16  and the sharps container cap  22 . The radiopharmacuetical pig  10  can be configured to hold syringes of various sizes, including those well known in the medical arts. 
     Referring now to FIGS. 1,  3 , and  5 , the cap  22  of the sharps container  12  preferably has a tubular, cup-like shape to accommodate the plunger  110  of the syringe  14 . Likewise, the sharps container housing  20  has a tubular shape to accommodate the body  102  and needle  106  of the syringe. In the alternative or in combination with the cap  22 , a similar, but shorter cap  112  may be used. The external dimensions of the caps  22  and  112  and the housing of the sharps container are sized so that they will nest within the upper  16  and lower  18  shields of the radiopharmaceutical pig  10 . 
     Each cap  22  and  112  has a closed end  114  and an open mating end  116  with an inwardly projecting circumferential ridge  118  that will deform as it slides downwardly over an outwardly projecting circumferential ridge  120  on the upper end of the housing  20 . Likewise, the ridge  120  on the housing may deform when the ridge  118  of the cap moves downwardly past the ridge on the housing. Each of the ridges has a beveled surface  122  so that the ridges may deform and pass by each other to snap the cap onto the housing. If only the smaller cap  112  is used with the housing for a particular application, cost savings should result because less material is required to make each cap and the lighter-weight caps should cost less to ship. 
     The caps  22  and  112  of the sharps container  12  may be made from a red-colored polypropylene, PVC, or other plastic material. If the sharps container is intended to comply with certain U.S. government regulations, e.g., 29 C.F R. §1910.1030, it should be labeled appropriately, such as having a red color, to signify that the sharps container contains regulated medical waste. Another way of satisfying this regulation is by labeling the sharps container with the word “biohazard” or the well known international biohazard symbol. 
     The housing  20  of the sharps container  12  nests within the cavity  34  of the lower shield  18 . The housing has a closed end  124 , an open mating end  126 , and an interior surface that defines an interior cavity  128 . The open mating end of the housing has its circumferential ridge  120  that engages the corresponding ridge  118  on either one of the caps  22  and  112 . The ridge in the housing also is sized to support the flange  104  of the syringe  14  and rest upon the circular wall  78  extending upwardly from the body  66  of the lower shield  18 . The hollow tubular housing is preferably made from a transparent polystyrene or other plastic material. Because the housing material is transparent, the interior of the housing can be viewed without disassembly of the sharps container. The entire housing need not be transparent, rather, the housing may be made from an opaque material having a small, transparent window that provides a view of the interior. The housing also need not be constructed of a transparent material if the contents of the sharps container can be ascertain by other means, such as by the appropriate labeling of the exterior of the sharps container. The housing and the caps may also be constructed from other materials of suitable strength. 
     The circumferential ridge  118  on the sharps container housing  20  is sized to support the flanged base  104  of the syringe body  102 , to support the syringe  14  so that its needle  106  and body are within the cavity  128  of the housing. Because the flanged base of the syringe rests on the ridge of the housing, the syringe is easily inserted with the needle pointing toward the closed end of the housing. Therefore, the fit between the shoulder of the housing and the flanged base of the syringe facilitates placement of the syringe into a position where the needle is immediately shielded within the housing. If the syringe is placed into the housing with its needle pointing upward, the needle poses a threat to persons trying to affix the cap  22  to the housing. Such persons are discouraged from such placement of the syringe because the syringe does not easily rest on the ridge of the housing when it is in such a reversed position. Futhermore, the sharps container  12  cannot be closed with the syringe pointing upward because the caps  22  and  112  preferably are not long enough to accommodate the body  102  and the needle of the syringe. Accordingly, the sharps container is advantageously configured to encourage the placement of the syringe with its needle safely protected within the housing. 
     The caps  22  and  112  and the housing  20  of the sharps container  12  resist the leakage of the radioactive drug, blood, or other contaminates from within the sharps container. As shown in FIG. 6, the O ring  60  likewise provides a seal between the upper and lower shields  16  and  18  of the radiopharmaceutical pig  10 . 
     Together, the radiopharmaceutical pig  10  and the sharps container  12  can be used to transport and dispose of the syringe  14  without contamination concerns. When a patient needs a dose of a radioactive drug, a healthcare worker, such as a doctor or nurse, transmits a prescription to a pharmacy, where the required drug is packaged in a syringe, using well known medical practices. A label containing information regarding the drug is preferably affixed to the body  102  of the syringe. The following information may be included on the label: the patient&#39;s name, the production lot number, the expiration date of the drug, the quantity of the drug, the name of the intended medical procedure, and possibly other relevant information, such as a relevant order number or the drug&#39;s radioactive half life. A larger label with similar information also may be affixed to the radiopharmaceutical pig  10 . The labels for the syringe and the radiopharmaceutical pig may contain any suitable information, such as words, bar code, or color code. It should be understood that the invention is not limited by the method of encoding and decoding the information contained on the labels, nor by the actual content of the information on the labels. 
     After the radioactive drug is packaged within the syringe  14  at the pharmacy, the sharps container housing  20  may be placed within the inner cavity  34  of the lower shield  18  of the radiopharmaceutical pig  10 . The syringe is then placed into the inner cavity  128  of the sharps container housing so that its capped needle  106  projects toward the closed end  124  of the housing. The larger cap  22  of the sharp container  12  may then be attached to the housing to prevent the syringe contents from contaminating the radiopharmaceutical pig. After the syringe has been used at the hospital, the larger cap  22  may be replaced upon the insert to enclose the spent syringe. Alternatively, the sharps container may not be used to deliver the syringe to the location for use if the pharmacy is content to rely upon the capped needle to prevent contamination of the radiopharmaceutical pig. In another alternative arrangement, the hospital may have a pre-ordered supply of large  22  or small  112  caps for use in enclosing spent syringes. In another embodiment, the short cap could be transported with the radiopharmaceutical pig from the pharmacy. 
     Next, the upper shield  16  of the radiopharmaceutical pig  10  is positioned above the lower shield  18  of the radiopharmaceutical pig so that the mating ends  26  and  30  of the upper and lower shields are in opposed alignment. The upper and lower shields are then moved together and rotated until the threads  54  of the upper shield engage the threads  56  of the lower shield. As shown in FIG. 2, the now-assembled radiopharmaceutical pig contains the sharps container  12  and the syringe  14  containing the radioactive drug. Once the upper portion  16  and the lower portion  18  of the radiopharmaceutical pig  10  have been joined, the radiopharmaceutical pig is placed in a shipping container (not shown) that may need to meet government regulations for the transportation of radioactive substances. 
     The shipping container may be transported to the destination of use (most likely a hospital) via motor vehicle, aircraft, hand cart, bicycle, or other delivery method. When the syringe  14  is needed for use, the radiopharmaceutical pig  10  is removed from the shipping container and the upper portion  16  is unscrewed from the lower portion  18 , to expose the cap  22  or  112  of the sharps container  12 . The cap may be conveniently pulled off of the housing  20  to expose the syringe. The syringe may be easily removed by use of well known safety procedures. The syringe may then be used to inject the patient, thereby discharging the radioactive drug from the syringe. After the injection, the syringe may be biologically contaminated and likely will contain a small amount of residual radioactive drug. 
     After the injection, the spent syringe  14  is inserted into the inner cavity  128  of the housing  20  of the sharps container  12 . The shorter sharps container cap  112  may then be placed over the syringe plunger  110 , so that the cap&#39;s mating end  116  is in opposed alignment with the mating end  126  of the housing  20 . The cap is then moved towards the housing until the circumferential ridges  118  and  120  snap past each other to attach the cap to the housing. Alternatively, the larger cap  22  may be affixed to the housing to enclose the spent syringe. 
     It should be appreciated that the ridges  118  on the caps  22  and  112  and the housing  20  of the sharps container  12  need not be in a precise alignment in order to connect the cap to the housing. Therefore, a healthcare worker may conveniently put the cap on the housing without bothering to align any clips on a cap with any receptacles on the housing, as is the case with at least one conventional radiopharmaceutical pig and sharps container combination. This feature is intended to save time and allow the worker to focus attention on other more important matters. 
     After the spent syringe  14  is safely contained within the sharps container  12 , the radiopharmaceutical pig  10  is assembled by threadably engaging the upper and lower portions  16  and  18  so that the sharps container is enclosed inside the radiopharmaceutical pig. The assembled radiopharmaceutical pig is placed in a shipping container for transport to the disposal area, which may be at the pharmacy. The shipping container is transported to the disposal area where the radiopharmaceutical pig is disassembled by threadably removing the upper portion from the lower portion. When the upper portion of the radiopharmaceutical pig has been removed, the cap  22  or  112  of the sharps container is exposed because it extends upward from the lower portion of the radiopharmaceutical pig. The sharps container is then removed, which allows the label on the syringe to be read through the transparent housing  20 . The information on the label enables a disposal worker to determine the proper disposal container for the syringe within the sealed sharps container. The sharps container, with the spent syringe inside, is disposed of by placing in the particular disposal container for radioactive material having the half-life of the radioactive residual. 
     A primary advantage of the device described above is that it can be handled easily because of its small size and because of the grip  62  and base  96  on the upper and lower shields  16  and  18 . Also, the use of the short cap  112  can automatically inform workers that the sharps container  12  contains a spent syringe  14 . Likewise, there is no plastic shell that completely encloses shields  16  and  18 . Therefore, breakage concerns relating to such plastic shells are alleviated. Upon opening the radiopharmaceutical pig  10 , a person is advantageously protected from the threat of an unshielded needle because the syringe is contained within the sharps container. 
     Yet another advantage of the present invention is the prevention of the contamination of the radiopharmaceutical pig  10  during the transport of the syringe  14  from the pharmacy to the point of patient treatment. The housing  20  of the sharps container  12  advantageously prevents the inner cavity  34  of the lower shield  18  of the radiopharmaceutical pig from becoming contaminated during this trip. If the syringe leaks, the radioactive drug should collect in the housing, thereby preventing the contamination of the lower shield. An additional level of protection can be had through the use of the cap  22  during the transport of the syringe from the pharmacy to the location of use. Furthermore, once the spent syringe is sealed within the sharps container, the inner cavities  32  and  34  of the upper  16  and lower  18  shield are advantageously protected from contamination while the radiopharmaceutical pig is moved to the disposal area. Accordingly, the invention advantageously saves the expense of the cleaning contaminated radiopharmaceutical pigs. 
     While a particular form of the invention has been illustrated and described, it will be apparent that various modifications can be made without departing from the spirit and scope of the invention. Thus, although the invention has been described in detail with reference only to the preferred embodiments, those having ordinary skill in the art will appreciate that various modifications can be made without departing from the invention. Likewise, it should be appreciated that the scope of the invention includes methods related to the above disclosure. Accordingly, the invention is not intended to be limited, and is defined with reference to the claims ultimately issued in a patent, and the equivalents thereof.