Medication dispenser for dispensing flat dosage forms

Information

  • Patent Grant
  • 6394306
  • Patent Number
    6,394,306
  • Date Filed
    Friday, June 23, 2000
    24 years ago
  • Date Issued
    Tuesday, May 28, 2002
    22 years ago
Abstract
A dispenser for storing/dispensing pharmaceutical dosages that are provided in a stamp-like (flat) dosage form. In some embodiments, the present dispenser includes a housing for retaining a plurality of stacked, individual “stamp-like” pharmaceutical dosages. Disposed within the housing beneath the dosages is a bias element, such as a helical spring, that urges the dosages towards a dosage delivery port of the housing. From the dosage delivery port, dosages are dispensed through an aperture. In other embodiments, the instant dispenser includes a cylindrical main body for retaining pharmaceutical dosages having a stamp-like dosage form that are collectively organized in a roll. A dosage delivery port depending from the cylindrical main body receives dosages one at a time therefrom. The present dispenser is configured, in various embodiments, for manual, mechanically assisted, or automated dispensing. Moreover, the present dispenser includes, when appropriately automated, control electronics that (1) alert a user of a scheduled dosage, and/or (2) dispense a dosage at a prescribed time or at a prescribed time interval, and/or (3) maintain a dosage record.
Description




FIELD OF THE INVENTION




The present invention relates generally to medication dispensers. More particularly, the resent invention relates to reusable medication dispensers for dispensing medications having a relatively “flat” dosage form.




BACKGROUND OF THE INVENTION




“Child-proof” medicine containers are a standard method for dispensing prescription drugs. The popularity of such containers is due, of course, to the difficulty that opening such containers presents to children. Ironically, these containers also pose difficulties for groups of people who are most likely to require the medicine that is stored therein. In particular, the aged, the handicapped, stroke victims, arthritis sufferers, individuals that have tremors and those recovering from accidents, surgery or serious disease conditions, among other individuals, may have trouble opening such child-proof medicine containers.




In response to this problem, specialized medication dispensers have been developed. Medication dispensers typically include one or more chambers for storing medicine(s) and various mechanisms for dispensing the medication. In some cases, the dispensers include motors so that when a user pushes a button, a pill is dispensed (see, e.g., U.S. Pat. No. 5,810,198). Some medicine dispensers include electronics that warn a user when it is time to take a pill, some restrict the dispensing of medication to certain prescribed times, and others automatically control delivery of multiple medications (see, e.g., U.S. Pat. Nos. 5,752,620, 4,310,103, and 5,752,621).




Most medication dispensers are designed to dispense small solid dosage forms such as tablets or capsules. If the final dosage form of a medication deviates from those common forms, dispensing may be problematic or impossible via standard dispensers. With the advent of new dosage forms, new types of medication dispensers are required.




SUMMARY OF THE INVENTION




A dispenser for dispensing medications having a flat or “stamp-like” final dosage form is disclosed. In some embodiments, a dispenser in accordance with the present teachings includes a housing for retaining a plurality of stacked individual pharmaceutical dosages. Within the housing and beneath the dosages is a bias element, such as a helical spring, that urges the dosages towards a dispensing end of the housing. The housing also includes a dosage delivery port that receives the pharmaceutical dosages one at a time from the interior of the housing.




In other embodiments, a dispenser in accordance with the present teachings includes a cylindrical main body for retaining a plurality of stamp-like dosages that are collectively organized in a roll. A dosage delivery port depending from the cylindrical main body receives dosages one at a time therefrom.




The dispensing operation for both stacked and rolled dosages can be carried out manually, manually with mechanical assist, or automatically via appropriate actuating mechanisms. In further embodiments, the present dispenser includes electronics that (1) alert a user of a scheduled dosage, and/or (2) dispense a dosage at a prescribed time or at a prescribed time interval, and/or (3) maintain a dosage record.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1A

depicts an electrostatically deposited pharmaceutical dosage form.





FIG. 1B

depicts a strip of stamp-like dosage forms.





FIG. 1C

depicts an individual stamp-like dosage form.





FIGS. 2A and 2B

depict an embodiment of a dispenser in accordance with the present teachings.





FIG. 3

depicts a further embodiment of a dispenser in accordance with the present teachings wherein the dosages are contained within a removable magazine.





FIG. 4

depicts an additional embodiment of a dispenser wherein the dosages are dispensed via a manual actuator.





FIGS. 5A and 5B

depict yet another embodiment of a dispenser in accordance with the present teachings wherein the pharmaceutical dosages are dispensed via a mechanized actuator.





FIG. 6

depicts pharmaceutical dosages having a stamp-like dosage form wherein the dosages are collectively organized in the form of a roll.





FIG. 7

depicts an embodiment of a dispenser in accordance with the present teachings for manually dispensing the rolled dosages of FIG.


6


.





FIG. 8

depicts a further embodiment of a dispenser that is configured for mechanized dispensing of the rolled dosages of FIG.


6


.





FIG. 9

depicts an illustrative electronically-driven mechanized actuator for dispensing the rolled dosages of FIG.


6


.





FIG. 10

depicts a simplified block diagram of electronics for imparting dosing, alarm and dose monitoring capabilities to the present dispenser.











DETAILED DESCRIPTION




The assignee of the present application has described a method and an apparatus for making a pharmaceutical unit dosage form or a diagnostic form using electrostatic deposition of biologically- or pharmaceutically-active ingredients. See, International Application PCT/US99/12772, incorporated by reference herein.




In accordance with PCT/US99/12772, unit dosage forms are fabricated by electrostatically depositing pharmaceutically-active powder(s) onto a pharmaceutical-grade substrate and then bonding a cover layer to the substrate over the powder(s).

FIG. 1A

depicts such a unit dosage form


100


. The unit dosage form comprises pharmaceutically-active powder


104


that is disposed between substrate


102


and cover layer


106


. Active powder


104


is advantageously disposed underneath bubble


108


in cover layer


106


.




In some embodiments, unit dosage forms


100


are incorporated into a secondary package to form any of a number of different “final” or “finished” dosage forms that are disclosed in PCT/US99/12772 or elsewhere. One final dosage form described in PCT/US99/12772 is referred to (therein and herein) as a “stamp” or “stamp-type” or “stamp-like” dosage form. The designation “stamp” acknowledges the resemblance of a diced (i.e., individual) dosage to a postage stamp.




In one embodiment, a stamp-like final dosage form comprises a unit dosage form


100


that is sealed between two polymer-based outer layers


152


and


156


(i.e., the “secondary package”). (See

FIGS. 1B and 1C

.) Typically, many of such unit dosage forms


100


are sealed within the secondary package forming a strip


150


of such stamp-like dosage forms, as depicted via an “exploded” view in FIG.


1


B.

FIG. 1C

depicts an individual dosage form


150


C, such as results from dicing strip


150


to separate the individual dosages. In embodiments in which unit dosage form


100


includes bubble


108


(FIG.


1


A), layer


156


that overlies cover layer


106


advantageously includes bubble


158


that receives bubble


108


.




Stamp-like dosage forms have shapes that are characteristically flat. The diced stamp-like dosage form


150


A is advantageously rectangular as shown in

FIG. 1C

, but it can also be circular or have any suitable shape, as desired. As will become clearer later in this Specification, stamp-like dosages forms may advantageously be organized into a 1×N strip. In embodiments in which stamp-like dosage forms are not diced into individual dosages (e.g., when they are organized in a 1×N strip), the secondary package advantageously has perforations (not shown) between adjacent dosage forms to facilitating removing an individual dosage from the collection thereof.




It will be appreciated that due to its physical configuration, the stamp-like dosage form, whether diced into individual dosage forms or grouped in a strip (both referenced hereinafter by the call out “150”), is not suitable for use in the typical prior art medication dispensers, such as are discussed in the Background section. The present invention provides several embodiments of a dispenser


200


that is suitable for dispensing pharmaceutical dosages that are configured in stamp-like dosage form


150


.




As used herein, the term “stamp-like dosage form” includes, in addition to dosage form


150


described above, other final dosage forms that are relatively flat in shape, but that may or may not be electrostatically deposited. In other words, it is not intended that the appended Claims be limited in scope to dosages that are formed via electrostatic deposition and/or to dosages that are sealed into a secondary package. That is, any dosage form that may suitably be dispensed from the present dispenser is considered to be a stamp-like dosage form as that term is used within this Description and the appended Claims. Those skilled in the art will be able to recognize other dosage forms that may suitably be used in conjunction with the present dispenser. Moreover, it will be recognized that while in some embodiments, the dosage comprises a single therapeutic agent, in other embodiments, the dosage comprises multiple therapeutic agents as may be used by patients on more than one therapy. Hereinafter, the term “dosage” and “dosage form” will be used synonymously.





FIGS. 2A

(exterior view) and


2


B (interior view) depict a first embodiment of medicine dispenser


200


for dispensing pharmaceuticals having a stamp-like final dosage form. Dispenser


200


comprises housing


202


having dosage delivery port


204


. The dosage delivery port


204


receives pharmaceutical dosages


150


, one at a time, from the interior of dispenser


200


through portal


206


located at dispensing end


208


of housing


202


.




Dosages are urged towards portal


206


via a bias element


210


. In the illustrated embodiments, bias element


210


is a helical spring that is placed in compression by dosages


150


.




The interior of housing


202


must be suitably configured to retain dosages


150


in a substantially orderly stack so that each dosage


150


is capable of being delivered to portal


206


and then to dosage delivery port


204


. In one embodiment, guides (not shown) within housing


202


maintain dosages


150


in stacked arrangement. In another embodiment, the open space within housing


202


takes the form of a shaft (not depicted) that restricts the movement of stacked dosages


150


to only one direction, which is upwards toward dispensing end


208


.




Dosage delivery port


204


has a receiving surface


212


that receives dosages


150


, one at a time, from portal


206


. Receiving surface


212


leads to aperture


214


, which is the site from which dosages


150


are dispensed from dispenser


200


.




In the embodiment illustrated in

FIGS. 2A and 2B

, dosages


150


are manually advanced to receiving surface


212


and from there to aperture


214


. To facilitate such manual operation, dosage delivery port


204


includes access way


218


through which a user can engage, with a finger, a dosage that is cued in portal


206


. Access way


218


is formed in top


216


of housing


202


.




Access way


218


is advantageously narrower across than dosages


150


. In particular, in the illustrated embodiment, top


216


extends inwardly beyond the side edges of receiving surface


212


thereby forming lips


220


. Channels


222


are defined between lip


220


and receiving surface


212


on both sides of dosage delivery port


204


. The “side” edges of dosages


150


engage channels


222


so that, among any other benefits, dosages will not fall out of dispenser


200


if it is inverted.




Moreover, the resilience of bias element


210


forces the top-most dosage


150


against the underside of lips


220


. Such upward pressure reduces the likelihood that dosages


150


could fall out of dispenser


200


.




Dispenser


200


advantageously includes ergonomic features. For example, in the illustrated embodiment, housing


202


includes ergonomic handgrip


224


configured to minimize strain on a user's hand/wrist.




In a second embodiment depicted in

FIG. 3

, dispenser


200


includes magazine


326


that stores a stack of dosages


150


. Magazine


326


, which is advantageously removable from housing


202


, ensures that dosages


150


remain in an orderly stack within housing


202


for problem-free dispensing. Additionally, it is easier and more convenient to load magazine


326


with dosages


150


(when the magazine is removed from housing


202


), than to load a plurality of such dosages directly into the interior of housing


202


as is required for the embodiment depicted in

FIGS. 2A and 2B

.




In the illustrated embodiment, bias element


210


is disposed within magazine


326


. In other embodiments, magazine


326


is physically configured so that bias element


210


is not contained within magazine


326


, but, rather, is disposed beneath it. This is accomplished in one embodiment by providing an opening (not shown) in the bottom of magazine


326


that receives bias element


210


and allows it to engage the bottom of the stack of dosages


150


. In another embodiment (not depicted), the bottom of magazine


326


is configured to slide within the sidewalls thereof. As dosages are removed from magazine


326


through portal


206


, the force imparted by bias element


210


forces the movable bottom of the magazine, and the overlying dosages


150


, upwardly. The slideable bottom of magazine


326


nears dispensing end


208


of housing


202


as the full complement of dosages


150


is dispensed therefrom.




In the previous embodiments, dosages


150


are manually advanced to receiving surface


212


and from there to aperture


214


.

FIG. 4

depicts an embodiment of dispenser


200


according to the present teachings in which a plunger


428


advances a dosage


150


from portal


206


to dosage delivery port


204


.




Plunger


428


does not include any mechanism that provides a mechanical advantage or that changes the direction of a manually applied actuating force. A user simply pushes plunger


428


, which, in turn, advances dosage


150


from portal


206


into dosage delivery port


204


. Plunger


428


is suitably configured, as desired, to advance a dosage either part of the way or completely through aperture


214


of dosage delivery port


204


. Dispenser


200


depicted in

FIG. 4

can be used with or without magazine


326


.





FIGS. 5A and 5B

depict an embodiment of dispenser


200


comprising a mechanized actuator


530


. Actuator


530


includes arm


532


that is operatively connected to solenoid


534


or like device. A power supply (not shown) supplies power to solenoid


534


. When a user pushes button


536


, power is sent to solenoid


534


, which in turn drives arm


532


into dosage


150


thereby moving it from portal


206


into dosage delivery port


204


. To provide sufficient space for actuator


530


, housing


202


may be somewhat larger than for the previously described embodiments. Magazine


326


is advantageously used for storing dosages


150


within housing


202


.




In some embodiments (not depicted), the mechanized actuator is manually “powered” (i.e., the actuating force is supplied by a user). In such embodiments, actuator


530


comprises mechanical linkages (not depicted) that drive arm


532


into dosage


150


using a force that is applied by a user to button


536


. Alternatively, other actuating arrangements that will occur to those skilled in the art may suitably be used.




The previous embodiments of dispenser


200


were directed to diced stamp-like dosage forms (see, FIG.


1


C). In further embodiments, the present dispenser is configured for dispensing a strip of stamp-like dosage forms


150


.





FIG. 6

depicts a roll


600


of stamp-like dosage forms


150


. Perforations


602


separate each individual dosage


150


to facilitate separating such dosages. In other embodiments (not shown), individuals dosage forms can be disposed on a carrier sheet (e.g., using a weak adhesive), rather than being linked by their secondary package to adjacent dosage forms as depicted in FIG.


6


.





FIG. 7

depicts an embodiment of medicine dispenser


700


for dispensing a roll


600


of dosages


150


. Dispenser


700


comprises housing


702


having cylindrical main body


706


suitable for receiving roll


600


. Dosage delivery port


704


depends from cylindrical main body


706


. Dosages


150


are received at dosage delivery port


704


one at a time from cylindrical main body


706


. Dosage delivery port


704


includes aperture


714


, which is the site from which dosages


150


are dispensed from dispenser


700


.




In the embodiment illustrated in

FIG. 7

, dosages


150


are manually advanced to dosage delivery port


704


and to aperture


714


. To facilitate such manual operation, dosage delivery port


704


includes access way


718


through which a user can engage, with a finger, a dosage that is cued in dosage delivery port


704


. Access way


718


is formed in top


716


of housing


702


.




Access way


718


in top


716


is advantageously narrower across than pharmaceutical dosages


150


. In particular, in the illustrated embodiment, top


716


extends inwardly beyond the side edges of aperture


714


forming lips


720


. The “side” edges of dosages


150


advantageously underlie lips


720


so that, among any other benefits, the end of roll


600


nearest aperture


714


will remain within the dispenser until such time as dosage


150


is dispensed.




A side


722


of housing


702


is advantageously removable or otherwise allows access to the interior of housing


702


to allow insertion of roll


600


of dosages


150


. In some embodiments, housing


702


contains a removable cartridge (not shown) that receives roll


600


for storage therein.




In the previous embodiment, dispenser


700


did not include any mechanism for advancing dosages


150


toward the dosage delivery port/aperture. In such an embodiment, dosages are dispensed, for example, by inserting a finger through access way


718


, engaging dosage


150


, and sliding it forward towards aperture


714


.

FIG. 8

(exterior view) and

FIG. 9

(interior view) depict an embodiment of dispenser


700


according to the present teachings comprising a drive mechanism


730


for advancing dosages


150


toward dosage delivery port


704


and aperture


714


for dispensing.




The illustrative dispenser


700


depicted in

FIG. 8

is very similar in external configuration to the dispenser depicted in FIG.


7


. Since dispenser


700


of

FIG. 8

has drive mechanism


730


, access way


718


for manually engaging dosages


150


is not required. The dispenser of

FIG. 8

includes button


744


that activates the drive mechanism.




In an illustrative depicted in

FIG. 9

, drive mechanism


730


comprises first roller


732


A, second roller


732


B and motor


740


, interrelated as shown. Each roller comprises two wheels (e.g.,


734


B and


736


B) that are rigidly connected by an axle (e.g.,


738


B). Drive shaft


742


is connected to motor


740


and turns when the motor is energized. A power supply (not shown) supplies power to motor


740


.




Wheels


734


A and


736


A (the latter not shown) of roller


732


A engage undersurface


604


(see

FIG. 6

) of the carrier sheet or secondary package of the dosage forms. Likewise, wheels


734


B and


736


B of roller


732


B engage top surface


606


(see

FIG. 6

) of the secondary package of the dosage forms. Drive shaft


742


operatively engages wheel


734


A.




When a user pushes button


744


, power is sent to motor


740


. The motor rotates drive shaft


742


, which, in turn, drives wheel


734


A. Wheel


734


A, which must maintain sufficient frictional engagement with undersurface


604


, drives dosage forms


150


towards through dosage delivery port


704


and aperture


714


. Sufficient frictional engagement is maintained by sandwiching dosage forms


150


between the first and second roller


732


A and


732


B.




In some embodiments, drive mechanism


730


is manually “powered” (i.e., the actuating force is supplied by a user). In one such embodiment (not depicted), the drive mechanism comprises the two rollers as shown, but not motor


740


. Rather, a crank engages, either directly, or through mechanical linkages, one of the rollers. As the crank is turned by hand, the rollers advance dosages


150


through aperture


714


. In another embodiment (not depicted), roll


600


of dosages


150


can be wound around a hub, the hub having a crank engaged thereto. As a user turns the crank, the hub turns, thereby advancing dosages


150


.




The operation of dispensers


200


and


700


can be enhanced by one or more advanced dispensing features. Such features include, among others, alerting the user to dispense a dosage, timed dispensing, and compliance record keeping. To that end, in further embodiments in accordance with the present teachings, dispensers


200


and


700


include dosing/alarm/monitoring electronics


800


, a figurative embodiment of which is depicted in FIG.


10


.




In the embodiment depicted in

FIG. 10

, electronics


800


includes processor


802


, memory


804


, timer


806


and alarm


808


. “Dosing” electronics (i.e., the functionality required for timed dosing) and “monitoring” electronics (i.e., the functionality required for dosage monitoring and recording) include processor


802


, memory


804


and timer


806


.




In some embodiments, memory


804


is used to store program code for operating the processor


802


, to store a user-defined dosing schedule and to store compliance/monitoring data. Memory


804


may comprise at least two separate memory devices since the program code should be in permanent memory while the dosing schedule and compliance data advantageously reside in programmable/erasable memory.




The dosing schedule, which is advantageously programmed by a user into memory


804


, can specify that a dosage is to be dispensed at a specific time (e.g., 8:00 a.m.) or, alternatively, can specify that dosages are to be delivered according to a time interval (e.g., every 4 hours). Timer


806


is used in conjunction with the dosing schedule to implement timed dosing.




In accordance with the dosing schedule, processor


802


sends an appropriate actuating signal to the actuator/drive mechanism


530


/


730


(more properly, to the actuator or mechanism “driver,” not depicted). The signal energizes actuator/drive mechanism


530


/


730


and a dosage is dispensed. Processor


802


advantageously updates the compliance record with information concerning the dispensed dosage (e.g., the time dispensed, etc.). Compliance data can be read out of memory


804


in known fashion.




To automatically dispense dosages according to a defined schedule, dispenser


200


or


700


must include sufficient automation (e.g., actuators, power supply, etc.) Thus, dosing electronics can only be used with suitably automated embodiments of the present dispenser. On the other hand, “alarm” electronics, which in some embodiments includes timer


806


and alarm


808


, can be used in conjunction with substantially non-automated embodiments of the present dispenser.




It is understood that the functionality represented by processor


802


, memory


804


and the timer and alarm may be suitably combined into fewer than four discrete devices. Those skilled in the art will know how to implement such dosing, alarm and monitoring electronics.




It is to be understood that the above-described embodiments are merely illustrative of the invention and that many variations can be devised by those skilled in the art without departing from the scope of the invention. It is therefore intended that such variations be included within the scope of the following claims and their equivalents.



Claims
  • 1. A dose dispenser, comprising:a housing for retaining a plurality of stacked individual dosages, each of said dosages being provided in a stamp-like dosage form; a bias element disposed within said housing, said bias element operative to urge said stacked dosages one at a time towards a dispensing end of said housing; and a dosage delivery port that receives said dosages one at a time from said dispensing end of said housing, wherein said dosage delivery port comprises: a flat receiving surface for receiving said dosages from said dispensing end of said housing; a first channel defining a first edge of said flat receiving surface; a second channel defining a second edge of said flat surface; and an aperture defined by an end of said first channel, an end of said second channel and an end of said receiving surface, wherein said dosages are dispensed from said aperture.
  • 2. The dose dispenser of claim 1 wherein said housing is physically adapted for ergonometric engagement with a user's hand.
  • 3. The dose dispenser of claim 1 comprising an actuator that advances said dosages, one at a time, into said dosage delivery port.
  • 4. The dose dispenser of claim 1 further comprising a magazine for receiving said plurality of stacked individual dosages, wherein said magazine is removably disposed within said housing.
  • 5. The dose dispenser of claim 4 further comprising an actuator that advances said dosages, one at a time, into said delivery port.
  • 6. The dose dispenser of claim 5 wherein said actuator is electrically actuated.
  • 7. The dose dispenser of claim 6 further comprising dosing electronics that are operable, in conjunction with said actuator, to dispense said individual dosages at specified times or at specified time intervals.
  • 8. The dose dispenser of claim 6 further comprising monitoring electronics that record dispensing statistics.
  • 9. The dose dispenser of claim 1 further comprising alarm electronics that alert a user that it is time to dispense a dosage.
  • 10. A dose dispenser comprising:a housing for retaining a plurality of stacked individual dosages, each of said dosages being provided in a stamp-like dosage form; a bias element disposed within said housing, said bias element operative to urge said stacked dosages one at a time towards a dispensing end of said housing; a magazine for receiving said plurality of stacked individual dosages, wherein said magazine is removably disposed within said housing; a dosage delivery port that receives said dosages one at a time from said dispensing end of said housing; and an electrically-actuated actuator that advances said dosages, one at a time, into said delivery port.
  • 11. The dose dispenser of claim 10 further comprising dosing electronics that are operable, in conjunction with said electrically-actuated actuator, to dispense said individual dosages at specified times or at specified time intervals.
  • 12. The dose dispenser of claim 11 comprising monitoring electronics that record dispensing statistics.
  • 13. The dose dispenser of claim 10 wherein said dosage delivery port comprises:a flat receiving surface for receiving said dosages from said dispensing end of said housing; a first channel defining a first edge of said flat receiving surface; a second channel defining a second edge of said flat surface; and an aperture defined by an end of said first channel, an end of said second channel and an end of said receiving surface, wherein said dosages are dispensed from said aperture.
  • 14. A dose dispenser, comprising:a housing for retaining a plurality of stacked individual dosages, each of said dosages being provided in a stamp-like dosage form; a bias element disposed within said housing, said bias element operative to urge said stacked dosages one at a time towards a dispensing end of said housing; a dosage delivery port that receives said dosages one at a time from said dispensing end of said housing; and alarm electronics that alert a user that it is time to dispense a dosage.
  • 15. The dose dispenser of claim 14 wherein said dosage delivery port comprises:a flat receiving surface for receiving said dosages from said dispensing end of said housing; a first channel defining a first edge of said flat receiving surface; a second channel defining a second edge of said flat surface; and an aperture defined by an end of said first channel, an end of said second channel and an end of said receiving surface, wherein said dosages are dispensed from said aperture.
  • 16. The dose dispenser of claim 14 comprising an actuator that advances said dosages, one at a time, into said dosage delivery port.
  • 17. The dose dispenser of claim 14 further comprising a magazine for receiving said plurality of stacked individual dosages, wherein said magazine is removably disposed within said housing.
  • 18. The dose dispenser of claim 17 further comprising an actuator that advances said dosages, one at a time, into said delivery port.
  • 19. The dose dispenser of claim 18 wherein said actuator is electrically actuated.
  • 20. The dose dispenser of claim 19 comprising monitoring electronics that record dispensing statistics.
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