Abstract:
A comic book case includes a base and a cover configured to compress and secure a comic book in place under frictional pressure such that the book cannot easily shift or slip within the case. Prior art cases that included walls surrounding the top, bottom and side edges of a book typically allowed some free movement or slippage of the book between the walls. This movement or slippage could result in damage such as curling or crinkling of the edges of the book if the case were exposed to a physical shock, such as by being dropped. The base includes a raised base platform and the cover includes a depressed cover platform, which extends towards the base platform to create a space within which the book is securely held.

Description:
RELATED APPLICATIONS 
     The subject matter of this application is related to U.S. Design patent application Ser. No. 29/557,254 filed Mar. 7, 2016 and titled CASE FOR AUTHENTICATED COMIC BOOK, and U.S. Design patent application Ser. No. 29/557,255 filed Mar. 7, 2016 and titled CASE FOR AUTHENTICATED COMIC BOOK, both of which applications are hereby incorporated by reference in their entireties. 
     BACKGROUND 
     Comic books and other collectible items such as books and magazines are bought and sold at trade shows and collectible item dealer stores. In addition, collectible items are increasingly being transacted over the Internet. In these types of transactions, purchasers are concerned that the item purchased is not authentic and/or not accurately described or graded. There exist commercial services that authenticate, grade, and encapsulate comic books submitted by owners. Once a comic book is graded, the service encapsulates the book within a tamper-evident transparent plastic case with a certificate indicating the description and grade of the book. The graded and encapsulated book, which is then returned by the service to its owner, becomes a more marketable item than one that is not graded and encapsulated. 
     In addition to establishing authenticity and grade, comic book cases also protect books from wear and tear. Damage can occur, for example, during shipping of a book that is otherwise not protected by a case. U.S. Pat. No. 5,415,290 describes a comic book protection cover system including an open ended bag formed of thin flexible transparent polypropylene and a rectangular rigid transparent insert. Space remains in the bag for receipt of the comic book adjacent the insert. U.S. Pat. No. 5,353,925 describes a preservation device for a collectible article in which a front and back panel define a cavity for receiving the collectible article. A spacing sheet positioned between the front and back panels creates a channel around the article. A gaseous substance is circulated around the channel. The gaseous substance is exposed to a desiccant for removing moisture. Screws are used to secure the back panel to the front panel. The article can be removed from the preservation device by unscrewing the screws. 
     U.S. Pat. No. 6,102,207 describes a collectible article holder providing readily observable positive evidence if tampering of the holder has occurred, thereby indicating that the item contained in the holder is authentic. The collectible article, such as a comic book, is placed in a core. Means for authenticating the collectible article is coupled to the core. The core is received in a cavity formed between a top and a bottom of a case. The top and bottom are ultrasonically bonded together. The case is designed to include means for positively indicating sealing of the top to the bottom which means form a visible irreparable condition of the case indicative of tampering. Key slots are formed in the side of the case to allow a purchaser after purchasing the collectible article to insert a tool, such as a screwdriver, in order to open the case. After the case is opened, the core layers can be peeled apart for allowing the purchaser to handle the collectible article. It will be appreciated that after the case has been opened, the collectible article is no longer certified as authentic. 
     SUMMARY 
     A comic book case includes a base and a cover configured to compress and secure a comic book in place under frictional pressure such that the book cannot easily shift or slip within the case. Prior art cases that included walls surrounding the top, bottom and side edges of a book typically allowed some free movement or slippage of the book between the walls. This movement or slippage could result in damage such as curling or crinkling of the edges of the book if the case were exposed to a physical shock, such as by being dropped. The base includes a raised base platform and the cover includes a depressed cover platform, which extends towards the base platform to create a space within which the book is securely held. Appropriately configured and sized bases and/or covers can be used to account for the necessary space to provide adequate frictional pressure for different thicknesses of books. In addition to comic books, the case can be configured in different shapes and sizes to hold other types of books, magazines, pamphlets, documents, or other types of articles. In accordance with different embodiments, the case can be configured with an appropriate size and shape to encapsulate substantially any flat article. 
     To assemble the case, a book, optionally enclosed in a clear plastic envelope bag, is placed on the base platform, and a certificate is placed on a certificate platform. The cover is placed over the base such that a set of posts extending up from the base are received in a corresponding set of receptacles in the cover. The engagement of the posts and receptacles, such as by friction or deformation of the posts and/or receptacles upon engagement, can provide tension to at least temporarily hold the cover to the base. The temporarily assembled case can then be permanently or semi-permanently assembled using ultrasonic bonding around part of all of mating surfaces on the base and cover which extend around the perimeter of the case. Ultrasonic bonding can also or alternatively be used to bond the posts to the receptacles, which can provide a visual indication of tampering if the bond between the posts and receptacles is broken or if the posts and/or receptacles themselves are broken. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an exploded view of a comic book case from a lower right side perspective in accordance with one embodiment. 
         FIG. 2  illustrates a second exploded perspective view of the case from an upper left side perspective. 
         FIG. 3  illustrates a front elevation view of the assembled case. 
         FIG. 4A  illustrates a high perspective view of the assembled case from a lower right side. 
         FIG. 4B  illustrates a low perspective view of the assembled case from the lower right side. 
         FIG. 4C  illustrates a low perspective view of the assembled case from the bottom side. 
         FIG. 5  illustrates a close perspective view showing detail of the upper left portion of the cover. 
         FIG. 6  illustrates a close perspective view showing detail of the lower left portion of the cover. 
         FIG. 7  illustrates a low perspective view of the assembled case from the right side. 
         FIG. 8  illustrates a low perspective view of the assembled case from the top side. 
         FIG. 9  illustrates a rear elevation view of the assembled case. 
         FIG. 10  illustrates a high side perspective view of the assembled case showing the base. 
         FIG. 11  illustrates a low perspective view of the assembled case showing the base from the bottom side. 
         FIG. 12  illustrates a low perspective view of the assembled case showing the base from the side. 
         FIG. 13  illustrates a low perspective view of the assembled case showing the base from the top side. 
         FIG. 14A  illustrates an embodiment of a case configured with an approximately 1 mm gap between the upper surface of the base platform and the lower surface of the cover platform. 
         FIG. 14B  illustrates an embodiment of a case configured with an approximately 3 mm gap between the upper surface of the base platform and the lower surface of the cover platform (this embodiment is also shown in all other figures). 
         FIG. 14C  illustrates an embodiment of a case configured with an approximately 5 mm gap between the upper surface of the base platform and the lower surface of the cover platform. 
         FIG. 15  illustrates an elevation view of the inside of the base. 
         FIG. 16A  illustrates a perspective view of the inside of the base from the lower right side. 
         FIG. 16B  illustrates a perspective view of the inside of the base from the upper left side. 
         FIG. 17  illustrates a close up perspective view of the upper left hand section of the inside of the base. 
         FIG. 18  illustrates a close up plan view of the upper right portion of the base. 
         FIG. 19  illustrates a close up perspective view of a lower corner portion of the inside of the base. 
         FIG. 20  illustrates an elevation view of the inside of the cover. 
         FIG. 21A  illustrates a perspective view of the inside of the cover from the lower right side. 
         FIG. 21B  illustrates a perspective view of the inside of the cover from the upper right side. 
         FIG. 22  illustrates a close up perspective view of the upper right hand section of the inside of the base. 
         FIG. 23  illustrates the same elevational view of the assembled case as  FIG. 3 , but with sight lines added that indicate the locations of cross section and cut-away views shown in  FIG. 24A-G . 
         FIG. 24A  illustrates a perspective view of a cut away through the case along sight line A. 
         FIG. 24B  illustrates a sectional elevation view through the case along sight line B. 
         FIG. 24C  illustrates a perspective view of a cut away through the case along sight line C. 
         FIG. 24D  illustrates a perspective view of a cut away through the case along sight line D. 
         FIG. 24E  illustrates a sectional elevation view through the case along sight line E. 
         FIG. 24F  illustrates a sectional elevation view through the case along sight line F. 
         FIG. 24G  illustrates a sectional elevation view through the case along sight line G. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, reference is made to the accompanying drawings, which form a part hereof, and which show, by way of illustration, specific embodiments or processes in which the invention may be practiced. Where possible, the same reference numbers are used throughout the drawings to refer to the same or like components. In some instances, numerous specific details are set forth in order to provide a thorough understanding of the present invention. The present invention, however, may be practiced without the specific details or with certain alternative equivalent devices, components, and methods to those described herein. In other instances, well-known devices, components, and methods have not been described in detail so as not to unnecessarily obscure aspects of the present invention. 
       FIG. 1  illustrates an exploded view of a comic book case from a lower right side perspective in accordance with one embodiment. The case includes a base  102  and a cover  104 , which are preferably each constructed of clear transparent rigid plastic. The base  102  and cover  104  can each be created, for example, using known injection molding processes. 
       FIG. 2  illustrates a second exploded perspective view of the case from an upper left side perspective. The exploded view of  FIG. 2  further shows a comic book  202  and a certificate  204  in relative position above where they would rest within the base  102 . The comic book  202  will typically include bound printed material with a thickness between 1 mm and 5 mm, and different thickness books can be accommodated by varying the depth and configuration of the base  102  and/or cover  104  in accordance with different embodiments. As will be noted from the drawings, the book  202  and the certificate  204  are only shown in  FIG. 2  and have been omitted from the remaining figures to more clearly illustrate the features of the base  102  and the cover  104 . 
     Referring to  FIG. 1 , when the case is assembled, the book  202  is compressed and held in place between an upper surface of a base platform  112  of the base  102  and a lower surface of a cover platform  114  of the cover  104 . The base platform  112  can be raised by way of steps  130  on 2 or more sides relative to surrounding portions of the base  102 . The cover platform  114  can be depressed by way of steps  130  on 2 or more sides relative to a surrounding upper portion  2020  ( FIG. 20 ) of the cover  104 . The raised base platform  112  and depressed cover platform  114  are shown more clearly in subsequent figures such as the cut-away perspective view of  FIG. 24C . The steps  130  that partially or completely circumscribe the base platform  112  and the cover platform  114  can function to counter deflection or bowing of the platforms by pressure exerted by the book on the platforms when the case is assembled. In accordance with one embodiment, the base  102  and the cover  104  are permanently assembled using ultrasonic bonding that surrounds part or all of the perimeters of the components. 
     Referring to  FIG. 2 , the case also includes a certificate  204  marked with a description of the book. In one embodiment, the certificate is made of heavy stock paper that is scored, by cutting partially through the paper&#39;s thickness, and folded along the score at a right angle. The fold creates a larger face portion  204 A and smaller tab portion  204 B of the certificate  204 . 
     When the case is assembled, the face portion  204 A of the certificate  204  rests on an upper surface of a certificate platform  122  of the base  102 . The face portion  204 A can be viewed through a certificate window  124  of the cover  104 . The certificate platform  122  can be optionally integrated into or made a part of the base platform  112 , such that the top surface of the certificate platform  122  and the base platform  112  lie in the same plane. The certificate platform  122  can be substantially separate from the base platform  112 , with one or more steps up and/or down between the platforms, such that the top surface of the certificate platform  122  and the base platform  112  lie in different planes. 
     When the case is assembled, the tab portion  204 B is fitted in a slot  230  (shown more clearly in  FIG. 18 ) formed between a top wall  210  of the base  102  and a number of vertically aligned fins  212  that extend outward from the certificate platform  122 . Both the face portion  204 A and the tab portion  204 B can include information identifying the book, such as a title, series and version. The face portion  204 A has additional space on which to include certification indicia and a grading indicating the condition of the book. When the tab portion  204 B is inserted into the slot  230  within the assembled case, the information on the tab portion can be viewed through the top wall  210  of the base  102 . In one embodiment, a separate label or certificate can be used instead of the tab portion  204 B. In one embodiment, one or more additional slots  230  can be formed on additional sides of the case, such as on the bottom, to accommodate additional labels. 
     In additional embodiments, one or more of the base platform  112 , the cover platform  114 , and the certificate platform  122  can be omitted in favor of a flat non-platform window panel that is not raised or depressed relative to the surrounding portions of the base  102  or cover  104 . 
       FIG. 3  illustrates a front elevation view of the assembled case. The base  102  and cover  104  are assembled such that the case has a top wall  210 , two side walls  310 , and a bottom wall  320 . 
       FIG. 4A  illustrates a high perspective view of the assembled case from a lower right side.  FIG. 4B  illustrates a low perspective view of the assembled case from the lower right side.  FIG. 4C  illustrates a low perspective view of the assembled case from the bottom side. 
       FIG. 4B  also shows an outer wall  410 , which bounds the perimeter of the case and which includes the top wall  210 , two side walls  310 , and bottom wall  320 . The outer wall  410  can be formed in part by each of the base  102  and the cover  104 , depending on how high the joint or break between the base  102  and cover  104  is positioned. In the illustrated embodiments, most of the outer wall  410  is formed by the base  102 . In additional embodiments, most of the outer wall  410  can be formed by the cover  104 , with the joint between the base  102  and the cover being located closer to the bottom of the base  102 . 
       FIG. 5  illustrates a close perspective view showing detail of the upper left portion of the cover  104 . Two steps  130 A and  130 B that form the upper and left side portions of the depressed cover platform  114  are visible.  FIG. 5  also illustrates how the both the depressed cover platform  114  and the certificate window  124  can are positioned lower relative to an outer ridge  510  of the cover  104  in one embodiment. 
     In one embodiment, the outer ridge  510  defines four corner features  520 , where the ridge takes turns around the perimeter of the case. The four corner features  520  facilitate stacking of multiple cases as will be discussed below with reference to  FIG. 9 . 
       FIG. 6  illustrates a close perspective view showing detail of the lower left portion of the cover  104 . Two steps  130 B and  130 C that form the left and lower side portions of the depressed cover platform  114  are visible. 
       FIG. 7  illustrates a low perspective view of the assembled case from the right side. 
       FIG. 8  illustrates a low perspective view of the assembled case from the top side. In one embodiment, the case can include a window area  810  on the top side of the case through which the tab portion  204 B of the certificate  204  can be viewed. The window area  810 , as shown, can extend along outside of the top wall  210  between near the left and right sides of the case, and between near the bottom of the base  102 , across the joint between the base  102  and the cover  104 , to near the top of the cover  104 . In certain embodiments, the window area  810  may not be visible or distinguishable from other areas of the case, for example, if the case is formed completely of clear transparent plastic and all of the outside portions of the case are polished. 
       FIG. 9  illustrates a rear elevation view of the assembled case. The underside of the base platform  112  and the certificate platform  122  are shown. In one embodiment, the base  102  includes a foot  902  near each the corner to stabilize the case when it is placed on a surface. Four feet  902 , one at each corner of the base  102 , can be configured to be receivable within the four corner features  520  of the outer ridge  510  of a cover  104  of another case. The matching between the feet  902  and the corner features  520  facilitates stacking of multiple cases atop one another such that the cases are prevented from sliding relative to one another by the interlocking of the feet  902  and corner features  520 . 
       FIG. 10  illustrates a high side perspective view of the assembled case showing the base  102 .  FIG. 11  illustrates a low perspective view of the assembled case showing the base  102  from the bottom side.  FIG. 12  illustrates a low perspective view of the assembled case showing the base  102  from the side.  FIG. 13  illustrates a low perspective view of the assembled case showing the base  102  from the top side. 
       FIG. 14A-C  illustrate three different embodiments of the case configured to accommodate different size comic books. The  FIG. 14A-C  each show a cut-away elevation taken along the top-bottom centerline of the assembled case.  FIG. 14A  illustrates an embodiment of a case configured with an approximately 1 mm gap between the upper surface of the base platform  112  and the lower surface of the cover platform  114 .  FIG. 14B  illustrates an embodiment of a case configured with an approximately 3 mm gap between the upper surface of the base platform  112  and the lower surface of the cover platform  114  (this embodiment is also shown in all other figures).  FIG. 14C  illustrates an embodiment of a case configured with an approximately 5 mm gap between the upper surface of the base platform  112  and the lower surface of the cover platform  114 . The same cover  104  can be used in each of the 1 mm, 3 mm, and 5 mm embodiments in conjunction with different bases  104 . 
       FIG. 14A-C  also show steps  130  that define the base platform  112  relative to a bottom portion  1410  of the base  104 . The bases  104  of the 1 mm and 3 mm embodiments can be configured with the same outer dimensions to produce assembled cases with the same outer dimensions. In the case of the 1 mm case, the base platform  112  is raised higher above the surrounding portions of the base  102  by using a larger step  130  to form the base platform  112 . The base  104  of the 5 mm case of  FIG. 14C  has a thicker overall dimension resulting in a thicker case overall relative to the assembled 1 mm and 3 mm cases to accommodate a larger book while still incorporating a step  130  to form the base platform  112 . Different embodiments can be configured to accommodate still different thickness books. Additional embodiments of the case can also be configured to accommodate books of different heights and widths in addition to different thicknesses. 
       FIG. 15  illustrates an elevation view of the inside of the base  102 .  FIG. 16A  illustrates a perspective view of the inside of the base  102  from the lower right side.  FIG. 16B  illustrates a perspective view of the inside of the base  102  from the upper left side.  FIGS. 15, 16A and 16B  show the base platform  112  as well as the certificate platform  122 .  FIGS. 15 and 16B  also show four vertically aligned fins  212  that extend outward from the certificate platform  122  leaving the slot  230  between the top wall  210  into which the tab portion  204 B of the certificate  204  fits. The slot  230  is more clearly shown in  FIG. 18 , discussed below.  FIG. 15  also shows the two side walls  310  and the bottom wall  320 . 
       FIGS. 15, 16A and 16B  also show a post  1510  in each corner of the base  102 . The four posts  1510 , which will be described in greater detail below with reference to FIG.  19 , are configured to be received in receptacles  2010  (shown and discussed below with reference to  FIGS. 20-22 ) in the cover  104  to temporarily hold the assembled case together before the case is permanently closed using ultrasonic bonding.  FIG. 15  also shows the base portion of the outer wall  410  that includes the top wall  210 , the side walls  310  and the bottom wall  320 . 
       FIG. 17  illustrates a close up perspective view of the upper left hand section of the inside of the base  102 . One of the posts  1510  is shown extending upward from a bottom portion  1410  of the base  102 . The certificate platform  122  includes a ridge  1710  that extends around three sides and upward from the upper surface of the certificate platform  122 . The ridge  1710  serves to fix the certificate  204  in place so that it does not become dislodged laterally. The ridge  1710  can optionally be configured to extend along two, three, or all sides of the perimeter of the certificate platform  122  in different embodiments. 
       FIG. 18  illustrates a close up plan view of the upper right portion of the base. The close up more clearly shows the thickness of the outer wall  410  of the case as well as a step  1810  that runs roughly along the center of the outer wall  410 . The step  1810  mirrors a matching inverse step in the perimeter of the cover such that the two steps fit together to align the base  102  and cover  104  upon assembly. The step  1810  is shown more clearly in  FIG. 19  and the cross sections of  FIG. 14A-C  and  FIG. 24A-G . The close up of  FIG. 18  also more clearly shows the slot  230  between the inner surface  1820  of the top wall  210  and the fins  212 . 
       FIG. 19  illustrates a close up perspective view of a lower corner portion of the inside of the base  102 . This perspective view more clearly shows the geometry of one of the posts  1510  as well as the step  1810 . The post  1510  extends upwards from a bottom portion  1410  of the base. In one embodiment, each post has a hexagonally shaped top section that is configured for a snug fit into a boss or receptacle  2010  (shown and discussed below with reference to  FIGS. 20-22 ). The post  1510  is preferably tapered such that as it is inserted into the receptacle  2010 , the edges of the hexagonal shape impinge upon the walls of the receptacle so as to hold the base  102  and cover  104  together. Although a hexagonal shape is shown, other shapes can be used, such as a cylinder or other polygonal shapes. 
       FIG. 20  illustrates an elevation view of the inside of the cover  104 .  FIG. 21A  illustrates a perspective view of the inside of the cover  104  from the lower right side.  FIG. 21B  illustrates a perspective view of the inside of the cover  104  from the upper right side.  FIGS. 20, 21A and 21B  show the depressed cover platform  114  as well as the certificate window  124 .  FIGS. 20, 21A and 21B  also show a receptacle  2010  for each post  1510  in each corner of the cover  104 . 
       FIG. 20  also shows an upper portion  2020  of the cover  104  relative to which the cover platform  114  is depressed (from the perspective of an assembled case) by way of steps  130 . 
       FIG. 22  illustrates a close up perspective view of the upper right hand section of the inside of the cover  104 . One of the receptacles  2010  is shown extending upward from a bottom (relative to the view) of the cover  104 . The certificate window  124  includes a ridge  2220  that protrudes from the inner surface of the certificate window  124  to match the ridge  1710  of the certificate platform  122 . The ridge  1710  of the certificate platform  122  and the ridge  2220  of the certificate window  124  preferably meet or interlock when the case is assembled to fix the certificate  204  in place so that it does not become dislodged laterally. The ridge  2220  can optionally be configured to extend along two, three, or all sides of the perimeter of the certificate window  124  in different embodiments.  FIG. 22  also shows a portion of the outer wall  410  of the cover  104  that interlocks with a portion of the outer wall  410  of the base  102 . 
       FIG. 23  illustrates the same elevational view of the assembled case as  FIG. 3 , but with sight lines added that indicate the locations of cross section and cut-away views shown in  FIG. 24A-G . Each sight line A-G in  FIG. 23  corresponds to an associated  FIG. 24A-G . 
       FIG. 24A  illustrates a perspective view of a cut away through the case along sight line A. A post  1510  is shown interlocking with a receptacle  2010 . The feet  902  and the outer ridge  510  of the cover  104  are also shown. 
       FIG. 24B  illustrates a sectional elevation view through the case along sight line B. The sectional view is taken through the bottom step  130  of the cover platform  114 . The base platform  112  and cover platform  114  are shown. 
       FIG. 24C  illustrates a perspective view of a cut away through the case along sight line C. The base platform  112  and cover platform  114  are shown bounding a space within which a book is held by the case. 
       FIG. 24D  illustrates a perspective view of a cut away through the case along sight line D. The sectional view is taken through a step  130  of the cover platform  114  between the cover platform and the certificate window  124 . The base platform  112  and cover platform  114  are shown. 
       FIG. 24E  illustrates a sectional elevation view through the case along sight line E. The sectional view is taken through a step  130  of the cover platform  114  between the cover platform and the certificate window  124 . The certificate platform  122  is shown. 
       FIG. 24F  illustrates a sectional elevation view through the case along sight line F. A post  1510  is shown interlocking with a receptacle  2010 . The fins  212  that hold the tab portion  204 B of the certificate  204  in place are also shown. The certificate platform  122  is shown. 
       FIG. 24G  illustrates a sectional elevation view through the case along sight line G. A post  1510  is shown interlocking with a receptacle  2010 . The fins  212  that hold the tab portion  204 B of the certificate  204  in place are also shown. 
     Referring again to  FIG. 2 , before being encapsulated in the case, a book  202  is optionally first placed in a clear plastic envelope or bag. The envelope can be, for example, a clear archival film envelope made of polyethylene terephthalate or Mylar. The envelope can be sealed on three sides and left open on one end, or a fourth side can be closed using a fold over tab on the envelope. 
     In order to assemble the case, the optionally enveloped book is placed on the base platform  112  and a scored and folded certificate  204  is placed on the certificate platform  122  with the tab portion  204 B extending down between the fins  212  and the top wall  210  of the base  102 . The cover  104  of the case is then fitted over the book  202  and certificate  204  and depressed such that the posts  1510  and receptacles  2010  engage to provide a temporary fixing of the assembly. The temporarily assembled case is then placed in an ultrasonic bonding machine, which is then activated to bond the base  102  to the cover  104 . The base and cover can be designed using known techniques such that ultrasonic bonding occurs along parts or all of the perimeters of the base and cover. In one embodiment, the bonding occurs along the sides of the perimeter of the case but not along the top and bottom of the perimeter of the case. 
     In addition or in the alternative to ultrasonic bonding around the perimeter, ultrasonic bonding can be configured to occur within or on the mating junctions of the posts and receptacles. By using ultrasonic bonding on the posts and receptacles, the posts and receptacles can be used as a visual indication of tampering with the assembled case. In some embodiments the number of posts and receptacles can be increased or decreased and any appropriate number of posts/receptacles can be spaced around the perimeter of the case to provide a semi-permanent bond between the base  102  and the cover  104 . The ultrasonic bond around the perimeter can be omitted so as to allow the case to be more easily disassembled in case a user wants access to the book inside. The breaking of the bonds between the posts and receptacles or the breaking of the posts/receptacles themselves, however, will provide a visual indication that the case has been opened. 
     Although the invention has been described in terms of certain embodiments, other embodiments that will be apparent to those of ordinary skill in the art, including embodiments which do not provide all of the features and advantages set forth herein, are also within the scope of this invention. Accordingly, the scope of the invention is defined by the claims that follow. It should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific implementations described above. The specific implementations described above are disclosed as examples only.