RESPIRATOR WITH PHASE CHANGE MATERIAL
20220168596 · 2022-06-02
Inventors
- Alyssa Sabolis (Midland, NC, US)
- Michael Lee Parham (St. Paul, MN, US)
- Amy Elizabeth Quiring (Matthews, NC, US)
- Ethan David Voss (Charlotte, NC, US)
- Antti Seppälä (Vaasa, FI)
- Gareth Roberts (Wrexham, GB)
- Graham Peter Wilson (Flintshire, GB)
- Troy Alan Baker (St. Asaph, GB)
- Carl Estcourt Tucker (Conwy, GB)
Cpc classification
A62B18/08
HUMAN NECESSITIES
A62B18/082
HUMAN NECESSITIES
A62B23/025
HUMAN NECESSITIES
A62B9/003
HUMAN NECESSITIES
International classification
A62B9/00
HUMAN NECESSITIES
A41D13/11
HUMAN NECESSITIES
A62B18/08
HUMAN NECESSITIES
Abstract
A respirator includes a frame, a filter layer, and a face seal member. The frame has an outer side and an inner side. The frame defines an opening therethrough. The filter layer is mounted to the outer side of the frame and covers the opening of the frame. The filter layer is configured to prohibit permeation of aerosol, gas, and/or vapor contaminants therethrough. The face seal member is mounted to the inner side of the frame. The face seal member includes a seal contact area configured to engage a facial surface of a wearer. The face seal member incorporates a phase change material therein. The phase change material is configured to provide localized cooling by absorbing heat emitted by the wearer.
Claims
1. A respirator, the respirator comprising: a shield; a frame defining an opening, the shield being mounted to the frame and at least partially covering the opening; an oronasal member mounted to the frame, the oronasal member including a seal contact area; a harness assembly having at least one strap coupled to at least one of the frame and the oronasal member; and at least one of the frame, the oronasal member, and the harness assembly incorporating a phase change material, the phase change material being arranged at least to provide localized cooling by absorbing heat emitted by a wearer, the phase change material melting at a predetermined temperature associated with the wearer.
2. The respirator of claim 1, wherein the phase change material is encapsulated by the at least one of the frame, the oronasal member, and the harness assembly that incorporates the phase change material.
3. The respirator of claim 1, wherein the phase change material is micro-encapsulated in a polymer coating prior to being incorporated into the at least one of the frame, the oronasal member, and the harness assembly.
4. The respirator of claim 1, wherein the oronasal member is formed of a filter media configured to prohibit permeation of aerosol contaminants through the filter media.
5. The respirator of claim 1, wherein the oronasal member is formed of at least one of a silicone, polyisoprene, halo-butyl, and a thermoplastic elastomer.
6. The respirator of claim 1, wherein the frame is a shield formed of nonpermeable plastic, the respirator further including at least one valve to allow for air exchange through the respirator, the at least one valve including a filter media configured to prohibit permeation of aerosol contaminants therethrough.
7. The respirator of claim 1, wherein the respirator further includes a rear-facing filter member, the rear-facing filter member disposed rearward of the frame and at least one of leftward, rightward, and downward of the seal contact area of the oronasal member.
8. The respirator of claim 1, wherein the frame includes an exhalation valve.
9. The respirator of claim 1, wherein the oronasal member has a convex structure that forms a cavity in the oronasal member, the phase change material being incorporated into the oronasal member adjacent to the cavity, the phase change material absorbing heat at least from air within the cavity to provide cooling inside the respirator.
10. The respirator of claim 1, wherein the phase change material is incorporated into the seal contact area of the oronasal member and absorbs heat to provide cooling to at least one surface that engages the seal contact area.
11. The respirator of claim 1, wherein the respirator is a half-face respirator.
12. The respirator of claim 1, wherein the respirator is at least one of a full-face respirator and an inner mask component of at least one of a full-face piece and a hood respirator assembly.
13. The respirator of claim 1, wherein the respirator further includes a lens mounted to the frame.
14. The respirator of claim 13, wherein the respirator further includes an outer sealing member mounted to at least one of the lens and the frame, the outer sealing member including another seal contact area, the phase change material being incorporated into the outer sealing member and absorbing heat emitted by the wearer.
15. The respirator of claim 13, wherein the phase change material is further incorporated into the lens to provide cooling inside the respirator.
16. The respirator of claim 1, wherein at least one of: at least a first portion of the phase change material melts upon absorbing heat; and at least a second portion of the phase change material solidifies upon releasing heat.
17. A respirator, the respirator comprising: a shield; a frame defining an opening, the shield being mounted to the frame and at least partially covering the opening; a lens mounted to the frame; an oronasal member mounted to the frame, the oronasal member including a seal contact area; a harness assembly having at least one strap coupled to at least one of the frame and the oronasal member; and at least one of the frame, the lens, the oronasal member, and the harness assembly incorporating a phase change material, the phase change material being arranged at least to provide localized cooling by absorbing heat emitted by a wearer, the phase change material melting at a predetermined temperature associated with the wearer.
18. The respirator of claim 17, wherein the respirator further includes an outer sealing member mounted to at least one of the lens and the frame, the outer sealing member including another seal contact area, the phase change material being incorporated into the outer sealing member and absorbing heat emitted by the wearer.
19. A respirator, the respirator comprising: a shield; a frame defining an opening, the shield being mounted to the frame and at least partially covering the opening; a lens mounted to the frame; an oronasal member mounted to the frame, the oronasal member including a seal contact area; outer sealing member mounted to at least one of the lens and the frame, the outer sealing member including another seal contact area; a harness assembly having at least one strap coupled to at least one of the frame and the oronasal member; and at least one of the frame, the lens, the oronasal member, the outer sealing member, and the harness assembly incorporating a phase change material, the phase change material being arranged at least to provide localized cooling by absorbing heat emitted by a wearer, the phase change material melting at a predetermined temperature associated with the wearer.
20. The respirator of claim 19, wherein the phase change material is encapsulated by the at least one of the frame, the lens, the oronasal member, the outer sealing member, and the harness assembly, and the phase change material is micro-encapsulated in a polymer coating prior to being incorporated into the at least one of the frame, the lens, the oronasal member, the outer sealing member, and the harness assembly.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION
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[0046] The respirator 100 may be a mask worn by a person, referred to herein as a wearer. The respirator 100 may be configured to protect the wearer from harmful contaminants, such as particulates, fumes, vapors, gases, and/or splattered liquids in the environment around the wearer by shielding the nose and mouth of the wearer to prohibit the wearer from inhaling or ingesting the harmful contaminants. The air supplied through the respirator 100 to the wearer may be filtered and at least partially purified by the respirator 100 prior to inhalation. The respirator 100 shown in
[0047] In one or more embodiments, the respirator 100 may be disposable or semi-disposable. A disposable respirator is configured to be disposed in its entirety after one or more uses by a wearer. A semi-disposable respirator may be at least partially disassembled or deconstructed, and at least some parts of the respirator may be disposed and other parts of the respirator may be sterilized or decontaminated before being reassembled with one or more new disposable parts for a subsequent use by a wearer.
[0048] The frame 102 may have an enclosed, inner side 108 and an exposed, outer side 110, with an opening 112 that extends through the frame 102 between the inner and outer sides 108, 110. The terms “inner” and “outer” are defined relative to the facial surface of the wearer (who is currently wearing the respirator 100), such that the inner side 108 of the frame 102 faces toward the wearer and is within the decontaminated facial area while the outer side 110 faces away from the wearer and is exposed to the environment. The frame 102 may be configured to provide structure and some rigidity to the respirator 100 to allow the respirator 100 to retain a defined shape. In an embodiment, the frame 102 may be at least partially convex, such that the frame 102 slopes or bulges outward away from the wearer. The opening 112 of the frame 102 optionally may occupy a majority of the area of the frame 102, such that the frame 102 itself forms a border around the opening 112.
[0049] The filter layer 104 may be mounted to the frame 102 such that the filter layer 104 covers the opening 112. In an embodiment, the filter layer 104 is mounted to the outer side 110 of the frame 102. The filter layer 104 seals to the frame 102 such that no gaps extend between the filter layer 104 and the frame 104 around the perimeter of the filter layer 104, and any air that enters the respirator 100 through the opening 112 in the frame 102 must permeate through the filter layer 104. The filter layer 104 may be semi-permeable and configured to allow some permeation of air therethrough while prohibiting permeation of aerosol contaminants with the air. As such, the filter layer 104 filters the air that permeates through the filter layer 104.
[0050] The face seal member 106 may be mounted to the frame 102. For example, the face seal member 106 may be mounted to the inner side 108 of the frame 102 while the filter layer 104 is mounted to the outer side 110. The face seal member 106 is designed to surround both the nasal and oral regions of the wearer. As used herein, the face seal member 106 may be referred to as an oronasal member 106. The face seal member 106 includes a seal contact area 114 that is configured to engage a facial surface of the wearer. For example, the seal contact area 114 may extend along a perimeter of the face seal member 106. The seal contact area 114 may contact the cheeks, the chin, and the nose of the wearer when the respirator 100 is worn by the wearer. The seal contact area 114 is configured to seal to the facial surfaces of the wearer to prohibit the passage of air between the face seal member 106 and the face of the wearer, as such air may be un-filtered and include harmful contaminants.
[0051] The respirator 100 also may include a harness assembly 116. The harness assembly 116 includes one or more straps 118 configured to removably mount the respirator 100 to a head of the wearer. The one or more straps 118 may be coupled to the frame 102 and/or the face seal member 106. The one or more straps 118 provide tension to hold the face seal member 106 in contact with the facial surface of the wearer to seal the respirator 100 to the wearer. The one or more straps 118 may be stretchable and/or include one or more adjustable straps to allow for a customized fit of the respirator 100 on the wearer. Optionally, the harness assembly 116 may include a harness cradle 160 (shown in
[0052] In an embodiment, at least one of the frame 102, the face seal member 106, the filter layer 104, or the harness assembly 116 includes a phase change material (PCM) incorporated therein.
[0053] The phase change material may be of any known phase change material chemistry including, but not limited to, organic substrates, inorganic substrates, and mixtures of both. By way of example, the phase change material may be at least one of a paraffin, a fatty acid, or a salt hydrate. Paraffin and fatty acids are organic, and salt hydrates are inorganic. The phase change material may have a high heat of fusion such that the material is capable of storing and releasing large amounts of energy. The phase change material may be selected or modified in order for the phase change material to change phase at a temperature or range of temperatures that includes or is proximate to the air temperature of the air exhaled by the wearer and/or the body temperature of the wearer (or, more specifically, the temperature at the facial surface of the wearer). For example, the exhalation air temperature may be around 34° C. and the body temperature of the wearer may be around 37° C. As such, the phase change material may be configured to change phase (for example, absorb or release latent energy) at a temperature between 30° C. and 40° C., and more preferably between 33° C. and 38° C. In an embodiment, the phase change material changes between solid and liquid states in this temperature range, but in other embodiments using other phase change materials, the phase change may be between liquid and gaseous states.
[0054] In an embodiment, the phase change material may be micro-encapsulated in a polymer coating prior to being incorporated into a component of the respirator 100. After micro-encapsulation, the phase change material may be co-molded with one or more of the components of the respirator 100 to form the respective component(s). In an alternative embodiment, the phase change material may be encapsulated by the primary material of the corresponding component of the respirator 100 (without first being encapsulated in a separate polymer coating). The components of the respirator 100 that may incorporate the phase change material include, for example, the face seal member 106, the frame 102, the filter layer 104, the harness assembly 116, and the like. The encapsulation of the phase change material prevents leakage of the phase change material out of the incorporated component(s). For example, the phase change material may be co-molded with silicone, polyisoprene, halo-butyl, and/or a thermoplastic elastomer to form the face seal member 106. The face seal member 106 may also be formed of a closed-cell polyurethane foam, and the phase change material incorporated therein.
[0055] Alternatively, or in addition, the phase change material may be integrated directly into the filter layer 104 during formation of the filter material. For example, the phase change material may be incorporated into an open-cell polyurethane foam that provides a breathing pathway. Thus, as described above the incorporation of phase change material may be integral integration during a forming process of a component of the respirator 100.
[0056] In an alternative embodiment, the phase change material may be incorporated onto a component of the respirator 100 after the component is formed by bonding a bed of phase change material to the component. For example, a patch or bed of phase change material may be bonded to the interior surface of the filter layer 104 that at least partially defines the cavity 128. Since the phase change material itself may be harmful if contacted against the skin directly, the phase change material optionally may be disposed on a component that does not contact the wearer directly or may be covered with an intermediate material that is safe to the touch but also allows thermal transfer between the facial surface of the wearer and the phase change material.
[0057] The phase change material is configured to provide thermoregulation at the boundary of contact between the wearer's face and at the boundary of contact between the wearer's face and the respirator 100. For example, the phase change material may provide localized cooling for the wearer by absorbing heat emitted by the wearer. The heat may be direct conductive heat emitted by a skin surface of the wearer directly into a component of the respirator 100 that engages the skin surface or convective heat that is absorbed from air exhaled from the wearer into the respirator 100. The phase change material may be configured to absorb heat without exhibiting a substantial increase in temperature by undergoing a phase change. For example, the heat that is absorbed is used to change the phase of at least some of the phase change material from a solid to a liquid phase. Latent heat is used to change the phase of the material and does not increase the temperature of the material. The temperature at which the phase change material melts, or changes from a solid to a gel or to a liquid, depends on the properties of the phase change material. In an embodiment, the phase change material that is incorporated into the respirator 100 melts at a temperature that is proximate to an exhalation air temperature of the wearer and/or a body temperature of the wearer.
[0058] As the phase change material absorbs heat and changes state, the facial surfaces and/or air proximate to the phase change material is cooled as the heat is dissipated away from the facial surfaces and/or air in the respirator 100. Thus, the incorporation of the phase change material may improve comfort of the wearer while wearing the respirator 100. Increased comfort of the wearer while wearing the respirator 100 reduces the urge or tendency of the wearer to remove the respirator 100 (or not even put on the respirator 100 in the first place) out of discomfort.
[0059] As stated above, the phase change material provides thermoregulation, and not only cooling. Thus, the phase change material may also provide heating to the air within the respirator 100 and/or the skin surfaces of the wearer based on the thermal conditions of the wearer and the ambient environment. For example, the phase change material may be in a liquid or gel state after absorbing heat emitted from the wearer. However, if the wearer enters an environment that is below a certain temperature, the phase change material may begin to undergo a reverse phase change process that causes the melted phase change material to return to a solid state. As the phase change material solidifies, heat is released from the phase change material, and the heat may be absorbed by the skin surfaces of the wearer and/or the air in the respirator 100 to provide localized heating. The release of heat may provide comfort to a wearer who is working outside, for example, in freezing or at least low temperatures. Thus, although one or more embodiments described herein are directed to the ability of the phase change material to provide cooling, it is recognized that the phase change material may also be used in each embodiment to provide heating. The phase change material provides thermal regulation by absorbing heat from the wearer upon melting to cool the wearer when the wearer is hot, and releasing the absorbed heat to the wearer upon solidifying to heat the wearer when the environment is cold.
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[0061] The frame 102 of the respirator 102 may be formed of a plastic material. For example, the frame 102 may be formed by a molding process. Depending on the plastic material, the frame 102 may be flexible, semi-rigid, or rigid to provide structure to the respirator 102. The frame 102 optionally may be a five-sided structure. One or more support beams 168 (shown in
[0062] The exhalation valve 120 of the frame 102 provides a port for the air that is exhaled from the wearer to exit the respirator 100. The exhalation valve 120 may be integral to the frame 102. Alternatively, the valve may be a snap-in valve. Optionally, the valve 120 may include an associated plenum that directs the air through a channel before or after flowing through the valve 120. The exhalation valve 120 may include filter media to prohibit outside air from entering the respirator 100 through the valve 120. Optionally, the exhalation valve 120 may be biased to open at a lower flow rate that is consistent with regular, non-elevated breathing rates (such as experienced by a healthcare worker). Resistance may be lower to ensure that a majority of the exhaled air exits through the exhalation valve instead of through inhalation filter media portions (for example, the filter layer 104) of the respirator 100. The exhalation filter media may have a targeted efficiency for filtering out larger biological contaminants (as compared to inhalation filter media used in an inhalation portion) in order to achieve the lower resistance. The exhalation filter media may also have a lower particulate loading capacity which is commensurate with the lower loading of biological particulate matter exhaled from the respirator 100 as opposed to the higher biological particulate loading in the ambient environment.
[0063] The filter layer 104 may include particulate filter media that is oriented into a textile or sheet. The filter layer 104 may include pleated or non-pleated electrostatic or synthetic membrane filter media. Synthetic membrane material may be re-usable due to being able to undergo common sterilization techniques. The filter layer 104 may be mounted to the outer side 110 of the frame 102 by insert molding, heat staking, ultrasonic welding, or the like. Optionally, the filter layer 104 may include an opening 122 at the exhalation valve 120 to allow the exhaled air to be discharged from the respirator 100. In one or more alternative embodiments, the outer layer of the respirator 100 may be a non-permeable or semi-permeable plastic shield instead of a filter layer 104, as described further herein.
[0064] The face seal or oronasal member 106 may be a formed of a silicone material, a thermoplastic elastomer material, and/or the like. The face seal member 106 may be molded such that the seal contact area 114 conforms around the nasal and oral regions of the wearer. The face seal member 106 optionally may be molded in a convex or c-shaped structure that bulges outward away from the wearer. Upon assembly of the respirator 100, the frame 102 and mounted filter layer 104 may be received over the face seal member 106. In an optional embodiment, the seal face member 106 may include one or more inhalation valves 152 (shown in
[0065] Optionally, the respirator 110 may be semi-disposable, and the face seal member 106 is removably mounted to the frame 102 and filter layer 104 to allow for disposal of the frame 102 and filter layer 104 and sterilization of the face seal member 106 and harness assembly 116. For example, the face seal member 106 may have integrated strap loops that are configured to receive the straps 118 of the harness assembly 116 therethrough. In another semi-disposable embodiment, the frame 102 and harness assembly 116 may be dismantled for sterilization while the filter layer 104 and face seal member 106 are disposed. In an alternative embodiment in which the respirator 100 is fully disposable, the face seal member 106 may incorporate the filter layer 104 and the combined material may be bonded to the frame 102, such as by heat staking, to construct the disposable respirator 100.
[0066] The one or more straps 118 of the harness assembly 116 may be formed at least partially of a stretchable material, such as neoprene, elastic, or the like. In other embodiments, the one or more straps 118 may not stretch, but may be coupled to adjustable coupling devices that allow the wearer to adjust the length of the one or more straps 118. For example, plastic buckles, hook and loop patches, “push to snap” butterfly clips, and other coupling devices may be located along the one or more straps 118. In an embodiment, the coupling device is located along the back of the neck of the wearer. In an embodiment, the harness assembly 116 may have a single strap 118 that loops twice around the head of the wearer, once along the bottom of the head or neck and again along the top of the head. The one or more straps 118 may have a single or double point attachment to the respirator 100. The one or more straps 118 optionally may include pads that provide padding for the wearer, and the pads may be formed of silicone, a thermoplastic elastomer, or the like. Optionally, the harness assembly 116 may include a harness cradle 160, as described further herein with reference to
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[0068] The inner region of the seal contact area 114 is open to allow the nose and mouth of the wearer to extend into the respirator 110 through the face seal member 106. The frame 102 and/or filter layer 104 may be at least partially convex and curved or bulged away from the face seal member 106 such that a cavity 128 is formed between the filter layer 104/frame 102 and the face seal member 106. The cavity 128 includes air that is to be inhaled by the wearer as well as air that is exhaled from the wearer. In an alternative embodiment, the frame 102 and/or filter layer 104 may not be convex but may be disposed a distance from the face seal member 106 such that the cavity 128 is formed.
[0069] The face seal member 106 shown in
[0070] In an embodiment, a phase change material is incorporated into one or more of the components of the respirator 100. For example, the phase change material may be incorporated into the seal contact area 114 of the face seal member 106. The phase change material on the seal contact area 114 may absorb heat directly from the skin of the wearer that engages the contact area 114. Alternatively, or in addition, the phase change material may be incorporated into the filter layer 104, the frame 102, and/or the face seal member 106 proximate to the cavity 128. As some examples, the phase change material may be incorporated into the filter later 104 that defines an outer wall of the cavity 128, the frame 102 which defines side walls of the cavity 128, and/or an outer surface of the face seal member 106 that defines an inner wall of the cavity 128. Incorporating the phase change material into surfaces that surround and define the cavity 128 allows heat from the air within the cavity 128 to be absorbed by the phase change material to cool the air within the respirator 100. Alternatively, or in addition, the phase change material may be incorporated into the formable nasal member 140 that is mounted to the seal contact area 114 in order to absorb heat directly from the nasal area of the wearer. Alternatively, or in addition, the phase change material may be incorporated in the strap 118 (or other components of the harness assembly 116 shown in
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[0080] The outer sealing member 180 is mounted to the frame 102. The outer sealing member 180 is formed of silicone, polyisoprene, halo-butyl, a thermoplastic elastomer, combinations thereof, or the like. The outer sealing member 180 includes a seal contact area 182 that is configured to engage a facial surface of the wearer. For example, the seal contact area 182 may contact a perimeter the face of the wearer, including but not limited to the forehead, cheeks, chin, and neck areas. The oronasal member 106 is mounted to the frame 102 and/or the outer sealing member 180. The oronasal member 106 is configured to surround and engage the nasal and oral regions of the wearer. The harness assembly 116 has one or more straps coupled to at least one of the frame 102, the lens 178, or the outer sealing member 180. The filter member (not shown) may be mounted within a defined opening in the frame 102 and/or the lens 178. For example, the filter member may be mounted within the inhalation valve assembly 190 and/or the exhalation valve assembly 188. The filter member may be a filter layer or a filter cartridge, depending on the placement and application. The filter member 184 is configured to prohibit permeation of aerosol, gas, and/or vapor contaminants therethrough.
[0081] At least one of the frame 102, the lens 178, the outer sealing member 180, the oronasal member 106, the harness assembly 116, or the filter member (not shown) includes a phase change material incorporated therein. The phase change material is configured to provide localized cooling by absorbing heat emitted by the wearer. The phase change material may be configured to melt at a temperature that is proximate to an exhalation air temperature of the wearer and/or a body temperature of the wearer. For example, phase change material incorporated into the outer sealing member 180 to absorb heat directly from the forehead, cheeks, chin, and/or neck of the wearer. In another example, the phase change material may be incorporated into the lens 178 to absorb heat from air within the respirator 100, such as air between the lens 178 and the facial surfaces of the wearer. The air may be within a cavity 192 that has a perimeter defined by the outer sealing member 180.
[0082] In accordance with one or more embodiments described herein, a respirator is provided that affords, among other technical effects, the technical effect of providing thermoregulation of areas in and on the respirator to provide comfort for the wearer of the respirator. One or more embodiments provide a technical effect of absorbing heat emitted by a facial surface of the wearer to provide cooling for the wearer. A technical effect may also include releasing heat onto a facial surface of the wearer and/or into air within the respirator when the ambient temperature is low to provide heating for the wearer. A technical effect of the respirator providing cooling and/or heating for the wearer is that the wearer will be more comfortable wearing the respirator, and will be more inclined to wear the respirator while exposed to aerosol, gas, and/or vapor contaminants in the air. A further effect of wearing the respirator will be that the wearer is less likely to be harmed by the contaminants in the air.
[0083] While various spatial and directional terms, such as front, back, left, right, lower, upper, horizontal, vertical, and the like may be used to describe embodiments of the present disclosure, it is understood that such terms are merely used with respect to the orientations shown in the drawings. The orientations may be inverted, rotated, or otherwise changed, such that an upper portion is a lower portion, and vice versa, horizontal becomes vertical, and the like.
[0084] While certain embodiments of the disclosure have been described herein, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.
[0085] It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. While the dimensions, types of materials and coatings described herein are intended to define the parameters of the invention, they are by no means limiting and are exemplary embodiments. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. § 112(f), unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.