Patent Application
20090171424
The present invention relates to apparatus and methods for heating biological tissue using RF energy.
The following published documents are believed to represent the current state of the art and the contents thereof are hereby incorporated by reference: US 2007/0106349, U.S. Pat. No. 5,755,753, U.S. Pat. No. 7,241,291, and WO/2007/117580.
The present inventors are now disclosing that when treating biological tissue (for example, skin tissue) with RF power, it is useful to do so using an applicator which mechanically vibrates when RF power is applied. In some embodiments, at least a portion of the applicator (for example, a portion in contact with an upper surface of the tissue) vibrates in a direction that is substantially perpendicular to an upper surface of the biological tissue.
In one non-limiting scenario, the device is used as follows: (i) the “vibrating RF applicator” of the presently-disclosed device is placed in contact with the skin surface; (ii) RF-power is delivered from the applicator to the skin, thereby heating, for example, underlying tissue layers; (iii) concomitant with the delivery of RF-power, at least a portion of the applicator, for example a skin-contacting portion of the applicator, is caused to mechanically vibrate.
In one non-limiting example, the presently disclosed device and treatment methods are useful for heating and contraction of adipose tissues and/or as a means of cellulite reduction. Thus, in one non-limiting example, the present inventor contemplates modifying a device similar to that disclosed in US 2007/0106369 (for example, a device including any combination or sub-combination of features disclosed in US 2007/0106369) to include a mechanical vibration generation device configured to cause a portion of the applicator to mechanically vibrate.
In yet another non-limiting example, the presently disclosed device and methods are useful for applications related to collagen restructuring and/or wrinkle treatment.
It is now disclosed for the first time an apparatus for treatment of a biological tissue of a subject comprising: a) an applicator contactable with a surface of the tissue; b) an RF power source configured to produce at least 20 Watts of REF power directed to the applicator; and c) a vibration generation device mechanically linked to the applicator, the vibration generation device being operative to generate mechanical vibrations of at least a portion of the applicator including mechanical vibrations having a frequency of at least 1 Hz and at most 100 Hz.
According to some embodiments, the apparatus further comprises a phase shifter operative to control a phase of electromagnetic wave carried the RF-power.
According to some embodiments, the apparatus further comprises an impedance matching network (IMN) operative to match an impedance power source to impedance of the biological tissue.
According to some embodiments, the apparatus further comprises an RF resonator connected to the applicator, the RF resonator operative to cyclically accumulate and release a desired amount of RF energy.
According to some embodiments, the applicator includes only a single electrode with a dielectric barrier associated with an outside surface of the applicator.
According to some embodiments, the applicator is made primarily from electrically conductive materials.
According to some embodiments, the RF power source, the applicator and the vibration generation device are configured so that, when the applicator is contacted to the surface of the biological tissue: i) the applicator is operative to deliver the RF power to the contacted biological tissue; ii) the vibration generation device is operative such that the mechanical vibrations of the at least a portion of the applicator include vibrations in a direction that is substantially parallel to a wavefront propagation direction of the RF power delivered from the applicator to the biological tissue.
According to some embodiments, the RF power source, the applicator and the vibration generation device are configured so that, when the applicator is contacted to the surface of the biological tissue: i) the applicator is operative to deliver the RF power to the contacted biological tissue via an applicator contact region of the applicator; ii) the vibration generation device and the applicator are operative such that an average direction of generated mechanical vibrations at the applicator contact region is substantially parallel to a wavefront propagation direction of the RF power delivered from the applicator to the biological tissue.
According to some embodiments, the vibration generation device and the applicator are configured such that the generated mechanical vibrations of the at least a portion include mechanical vibrations having a frequency of at least 2 Hz and at most 10 Hz.
According to some embodiments, the vibration generation device and the applicator are configured such that the generated mechanical vibrations of the at least a portion include mechanical vibrations having an amplitude of at least 0.1 mm and more. In different embodiments, the amplitude may be at least 0.2 mm, 0.3 mm, 0.5 mm or 1 mm.
According to some embodiments, the vibration generation device and the applicator are configured such that the generated mechanical vibrations of the at least a portion include mechanical vibrations having an amplitude of at most 10 mm.
According to some embodiments, the vibration generation device includes a linearly oscillating mass.
According to some embodiments, the vibration generation device includes: i) a rotary motor; and ii) a rotary-to-linear motion converter operatively linked to the motor.
According to some embodiments, the vibration generation device is embedded within the applicator.
According to some embodiments, the vibration generation device is operative to generate remote vibrations remote to the applicator and the apparatus further comprises: a vibration transmitter operative to transmit the remote vibration to the applicator. Exemplary mechanisms for transmitting the remote vibration include but are not limited to hydraulic mechanisms and pneumatic mechanisms.
According to some embodiments, the vibration generation device includes at least one of: i) an electromagnetic actuator; ii) a piezoelectric actuator; and iii) a magnetostrictive actuator.
According to some embodiments, i) the apparatus further comprises a tissue softness detector operative to detect a softness of the biological tissue contacted by the applicator and ii) the vibration generation device includes a vibration controller operative to provide at least one of a vibration frequency and a vibration amplitude in accordance with results of the tissue softness detecting.
According to some embodiments, the vibration controller is operative to provide in increased frequency contingent on detecting increased tissue softness.
According to some embodiments, i) the apparatus further comprises a applicator movement speed detector operative to detect at least one of speed and a trajectory of the applicator; and ii) the vibration generation device includes a vibration controller operative to provide at least one of a vibration frequency and a vibration amplitude in accordance with results of at least one of the speed detecting and the trajectory detecting.
According to some embodiments, the vibration controller is operative to provide in increased frequency contingent on detecting an increased applicator speed.
According to some embodiments, i) the apparatus further comprises a pulse width modulation controller operative to cause the RF power source to deliver the RF output signal in pulses of a given duration at a given repetition rate; and ii) the vibration generation device is operative to provide the vibration of the at least a portion at a mechanical vibration frequency determined in accordance with the RF pulse repetition rate.
According to some embodiments, the vibration generation device is operative such that the a ratio between the mechanical vibration frequency and the RF pulse repetition rate is one of:
i) an integer; and ii) a reciprocal of an integer.
According to some embodiments, the vibration generation device and the applicator are operative to provide maximum compression at times that are substantially a time of a RF pulse maximum of RF pulses.
According to some embodiments, the vibration mechanism includes: i) a motor; and ii) an eccentric weight mechanically coupled to the motor.
According to some embodiments, the vibration mechanism includes: i) a magnetic weight; and ii) one or more electromagnets operative to cause the magnetic weight to oscillate.
According to some embodiments, the vibration mechanism is operative to generate the mechanical vibrations of the at least a portion in a direction that is substantially perpendicular to a contact surface of the applicator.
According to some embodiments, the apparatus further comprises: d) a cooling device for cooling at least a portion of the biological tissue.
According to some embodiments, the apparatus lacks a cooling device.
According to some embodiments, the apparatus lacks a ground electrode for receiving electric current of the produced RF power.
According to some embodiments, the apparatus lacks a ground electrode for receiving electric current of the produced RF power.
It is now disclosed for the first time a method of treating biological tissue, the method comprising: a) delivering at least 10 Watts of RF power to the biological tissue from an applicator in contact with the biological tissue; b) concomitant with the RF power delivering, generating mechanical vibrations by a vibration generation device including vibrations having a frequency of at least 1 Hz and at most 100 Hz; and c) delivering the generated mechanical vibrations to the biological tissue.
According to some embodiments, the mechanical vibrations are delivered so as to repeatedly provide compression to the biological tissue at or beneath a contact interface between the applicator and the biological tissue at the frequency.
According to some embodiments, at least 10 consecutive cycles of the mechanical vibrations are delivered to the biological tissue. In different embodiments, at least 5 consecutive cycles, at least 15 consecutive cycles, at least 20 consecutive cycles, and at least 50 consecutive cycles are delivered.
According to some embodiments, at least 20 watts of the RF power is delivered to the biological tissue.
According to some embodiments, the method is performed for cellulite reduction.
According to some embodiments, the method is performed for collagen remodeling.
According to some embodiments, the method further comprises: c) controlling a phase of an electromagnetic wave carried by the delivered RF-power so that the delivered RF power is concentrated primarily in a predetermined energy dissipation zone, which lies at a desired depth beneath a surface of the biological tissue. According to some embodiments, the method further comprises: c) matching an impedance of a power source of the RF power with an impedance of the biological tissue.
According to some embodiments, the RF power delivery includes cyclically accumulating and releasing a desired amount of RF power.
According to some embodiments, the RF power is delivered to the biological tissue via a dielectric barrier.
According to some embodiments, mechanical vibrations of the biological tissue include vibrations in a direction that is substantially parallel to a wavefront propagation direction of the delivered RF power.
According to some embodiments, an average direction of the mechanical vibrations of the biological tissue caused by the vibration generation device is substantially parallel to a wavefront propagation direction of the delivered RF power.
According to some embodiments, the vibration generation device resides at least in part within the applicator.
According to some embodiments, the vibration generation device resides outside of the applicator.
According to some embodiments, the delivered mechanical vibrations have an amplitude of at least 0.1 mm. In different embodiments, the amplitude may be at least 0.2 mm, 0.3 mm, 0.5 mm or 1 mm.
According to some embodiments, an amplitude of the mechanical vibrations is at least 0.005 times a square root of a surface area of a contact interface between the applicator and the biological tissue.
According to some embodiments, the vibration generation device includes at least one of: i) a linearly oscillating mass; ii) a rotating eccentric weight; iii) an electromagnetic actuator; iv) a piezoelectric actuator; vi) a mangetostrictive actuator.
According to some embodiments, the method further comprises d) detecting a softness of the biological tissue; wherein at least one of a vibration frequency and a vibration amplitude of the delivered mechanical vibrations are determined in accordance with results of the tissue softness detecting. According to some embodiments, an increased the frequency is provided contingent on a detecting of an increased tissue softness.
According to some embodiments, the method further comprises d) detecting at least one of a speed and a trajectory of the applicator; wherein at least one of a vibration frequency and a vibration amplitude of the delivered mechanical vibrations are determined in accordance with results of at least one of the speed and the trajectory detecting.
According to some embodiments, i) the delivered RF power is pulsed RF power; and ii) at least one of an amplitude and a frequency of the delivered mechanical vibrations is determined in accordance with at least one pulse parameter of the pulsed RF power.
According to some embodiments, a ratio between a frequency of the delivered mechanical vibrations and a RF pulse repetition rate of the RF power is one of: i) an integer; and ii) a reciprocal of an integer.
According to some embodiments, the generated mechanical vibrations are delivered so as to provide maximum compressions at times that are substantially times of an RF pulse maximum of the pulsed RF power.
According to some embodiments, the method further comprises: d) cooling a surface of the biological tissue.
According to some embodiments, the method is carried out without cooling a surface of the biological tissue.
According to some embodiments, the delivered RF power is delivered from an apparatus lacking a ground electrode.
According to some embodiments, the delivered RF power is delivered from an apparatus having a ground electrode.
It is now disclosed for the first time a method of treating biological tissue, the method comprising: a) delivering at least 10 Watts of RF power to the biological tissue from an applicator in contact with the biological tissue; b) concomitant with the RF power delivering, using a vibration generation device, generating mechanical vibrations of at least a portion of the applicator including vibrations having a frequency of at least 1 Hz and at most 100 Hz.
These and further embodiments will be apparent from the detailed description and examples that follow.
While the invention is described herein by way of example for several embodiments and illustrative drawings, those skilled in the art will recognize that the invention is not limited to the embodiments or drawings described. It should be understood that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention. As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning “having the potential to”), rather than the mandatory sense (i.e. meaning “must”).
The invention is herein described, by way of example only, with reference to the accompanying drawings. With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the exemplary system only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how several forms of the invention may be embodied in practice.
Reference is now made to
The treatment apparatus 10 of
In the non-limiting example of
Typically, the mechanical vibrations have a frequency of between 1 Hz and 100 Hz, and amplitude of between 0.1-10 mm.
In some embodiments, the mechanical vibrations the mechanical vibrations have a frequency of between 1 Hz and 10 Hz.
As noted above, treatment apparatus 10 of
As discussed in US 2007/0106349, in some embodiments, phase shifter 130 is useful for shifting a phase of directed traveling waves of the output RF signal so that RF power is delivered “deeper layers” of treatment. Thus, in some embodiments, phase shifter 130 is provided to alter the RF output signal phase so that energy in concentrated at a predetermined zone at a desired depth beneath the surface of biological tissue.
Furthermore, in some embodiments, RF-signal supplying assembly 185 includes a feeding half-wave cable, for example, as discussed in US 2007/0106349.
In some embodiments, IMN 140 is operative to match the impedance of biological tissue 200 from a nominal value (e.g. 250-350 Ohms) to a corrected value, for example, an output impedance of RF-generator (e.g. 50 Ohms). The corrected value matches an impedance characteristic of RF energy generator 120 and RF transmission line including phase shifter 130 and feeding cable 175 so that reflection power from the treating tissue is minimal.
In the particular example of
The apparatus in
It is appreciated that RF-signal supplying assembly 185 is not required, in every embodiment, to include every component in
There is no limitation on the dimensions of applicator 240. In one non-limiting example, the applicator diameter is from 5 to 25 mm, for example between 10 and 18 mm.
In the example of
Thus, in some preferred embodiments, the provided treatment apparatus 10 is a unipolar device where applicator 240 functions as a single device electrode or electromagnetic “coupler” in physical or capacitive contact with and radiatively coupled with the biological tissue 200.
In alternate embodiments, treatment apparatus 10 is a so-called “bipolar” devices (i.e. including vibration generation device 190) for delivering RF power to biological tissue that feature a ground plane electrode (not shown).
As noted, in some embodiments, RF-signal supplying assembly 185 includes pulse width modulator controller 110, capable of causing the RF energy source to deliver the output signal in pulses of a desired amplitude, a predetermined duration with a desired repetition frequency for average output power control. One exemplary pulse width modulator controller 110 is described in US 2007/0106349.
In one particular example, 25-300 watts of power are delivered, the operating RF-frequency is 40.68 MHz, a PWM-frequency is 0.5 to 50 kHz and a duty cycle is 1 to 100%.
Specifically, in these embodiments, control of phase and pulse with modulation (PWM)-control of applied RF waves through conductive applicator 240 which functions as or includes “a single electrode” may obviate the need for cooling of the skin surface while facilitating efficient heating of underlying layers of tissue such as dermis and subcutaneous layers.
Application of high RF-power in short-pulses may provide fast and effective heating of cellulite capsules with relatively low average RF-power level.
In some embodiments, treatment apparatus 10 includes a cooling element for cooling a skin surface.
In the present section, it is disclosed that in some embodiments, it is advantageous to have at least a portion of applicator 240 (typically a lower “contact” surface 205) mechanically vibrate in a direction substantially (for example, within a tolerance of 45 or 30 or 15 degrees) “perpendicular” to an upper surface of tissue 200.
As illustrated in the figures, both applicator 240 and resonator 150 are associated with handpiece 100. In one use scenario, a user (for example, a medical professional administering the RF energy) moves handpiece 100 including applicator 240 over the surface of the biological tissue 200 to treat the tissue. When “applicator contact region” 205 of the lower surface of applicator 240 contacts a “tissue surface contact region” 210 of the upper surface of the biological tissue 200, RF power is delivered from the applicator 240 to the biological tissue 200. As shown in
As shown in
It is noted that each location within the “contacting region 210” of the upper surface of biological tissue (i.e. the portion of the upper surface in contact with applicator 240) may be associated with a “local surface vector” perpendicular to the local plane at the contacting location. The entirety of the “contacting region 210” of the upper surface of the biological tissue may be associated with a “contacted surface vector” (not shown) that is the average of all of the aforementioned local surface vectors. In the example of
In embodiments where “vibration direction vector” 215 is substantially parallel to the contacted surface vector and/or RF Wavefront Propagation Vector 225, it is noted that the vibration may be useful for alternatively compressing the biological tissue 200 and allowing the biological tissue to “relax” or return to its “uncompressed form.”
The present inventor is disclosing that this may be useful when concomitantly treating the biological tissue with RE power to heat the biological tissue 200.
As noted earlier, in different embodiments, the treatment apparatus 10 may include any combination of one or more features disclosed in US 2007/0106349. Thus, it is noted that in various embodiments, applicator 240 (i) is made primarily from “conductive” materials (for example, having an electrical conductivity that exceed a conductivity of iron, or that exceeds a conductivity of nickel, or that exceeds a conductivity of tungsten) for example one or more metals including but not limited to Al, Ag, Au, copper, and/or alloys thereof and (ii) is associated with a dielectric material 220 that serves as a barrier between the conductive applicator and the biological tissue. In one non-limiting example, the dielectric material 220 is provided as a coating to the conductive material of applicator 240.
In the examples of
In some embodiments, certain teachings of U.S. Pat. No. 6,481,104 and U.S. Pat. No. 5,299,354, incorporated herein by reference, are adopted for the vibration generation device 190.
In
In the example of
It is appreciated that these are merely a few examples, and that other vibration generation device 190 configurations (i.e. other than those explicitly illustrated in the present examples) for generating vibrations to impart mechanical vibrations to at least a portion of applicator 240 may be used.
In one non-limiting example, vibration generation device 190 includes a piezoelectric device and/or magnetostrictive actuator to provide mechanical vibrations.
In step S109A, RF energy is delivered to the biological tissue at a time at least a portion of RF applicator 240 vibrates.
It is noted for all “flow diagrams” provided herein that although the steps may be carried out in the order specified (for example, the vibrations of S105 may of course commence before contact between applicator 240 and biological tissue 200 is established), this is certainly not a requirement.
In some embodiments, vibration generation device 190 is operative to cause at least a portion of applicator (for example, a lower surface 205 in contact with an upper surface 210 of the biological tissue 200) to vibrate with an amplitude of between 0.2 and 6 mm. It is also appreciated that different vibration frequencies (i.e. for vibration of at least a portion of applicator 240 and/or provided by vibration generation device 190) may be used in different embodiments. In some embodiments, the frequency is between 1 Hz and 100 Hz. In some embodiments, the frequency is between 2 Hz and 10 Hz.
It is appreciated that the amplitude may vary between individual vibration cycles, and is not necessarily constant. Additionally, it is appreciated that the “vibration frequency” is not required to be constant and may vary between vibration cycles.
In some embodiments, the vibration parameters are “fixed” and/or “hardwired.” Alternatively, the vibration parameters may be provided by a user of the apparatus 10 (for example, a medical professional) and/or may be provided by the apparatus 10 itself (or a component thereof) in response to one or more detected parameters.
Thus, in the example
According a first use scenario, causing at least a portion of applicator 240 to vibrate may be useful, for example, when it is desired to facilitate contact between a lower surface of applicator 240 and an upper surface of biological tissue 205.
Thus one example relates to “soft tissue” which may have a tendency to “move” during treatment. The present inventor notes that, the likelihood of “losing contact” (i.e. touch and capacitive coupling) when treating softer tissue may be greater than the likelihood of “loosing contact” when treating harder tissue.
The present inventor is now disclosing that mechanical vibrations of at least a portion of applicator 240 (such as a lower “contact” surface 205) are useful for increases the probability of contact during a time period when contact may otherwise be lost by a “rule of averages”—i.e. since the instantaneous location (i.e. for example, in the “z” direction perpendicular to the local surface of the biological tissue) of the lower surface 205 of applicator 240 changes in time due to the vibrations, on average the probability that the lower surface 205 of applicator 240 would be in the “right location” for contacting tissue 240 at least “some” of the time would increase due to the mechanical vibrations.
Thus, according to a first use scenario, the user (e.g. for example, medical practitioner administering the RF treatment to the subject of the biological tissue) may (i) note that s/he is to treat “soft tissue”; and (ii) input, via user interface 220 (or “device controls”), a set of vibration parameters that includes a “higher” mechanical vibration frequency.
According to a second use scenario, the present inventor is noting that as the speed v of applicator 240 over the surface of biological tissue increases, it is possible that the probability of “losing capacitive contact” between a lower surface 205 of applicator 240 and biological tissue 200 may increase due to applicator speed. Thus, according to this scenario, the user or RF treatment administrator may select, via device controls 220, a higher frequency when s/he intends to use a “higher” applicator 240 speed.
Alternatively or additionally, one or more vibration parameters may be provided “implicitly.” Thus, in some embodiments, the user interface 220 is operative to receive (i) information such as handpiece moving speed (or alternatively, a selection from a pre-determined list such as “slow speed,” “medium speed,” and “fast speed”); and/or (ii) information such as tissue softness; and/or (iii) any other information. In accordance to the information received via user interface 220, one or more vibration parameters (for example, frequency or amplitude) may be computed.
A Discussion of Several Routines for “Automatically” or “Adaptively” Selecting and/or Adjusting Vibration Parameters in Response to One or More Detected Physical Parameters
In
In step S113, a velocity and/or trajectory of the applicator 240 is detected. Any known technique or apparatus for determining applicator 240 position or velocity (mechanical, electrical or otherwise) may be used.
In one non-limiting example, the position of applicator 240 is detected using ultrasound “triangulation” position detecting system. For example, the applicator 240 may be associated with or connected to or include an ultrasound transmitter and an IR transmitter. In addition, two or more ultrasound receivers (i.e. whose position is fixed in space) and one or more IR receiver may be provided. Using the IR signal for synchronization, time or flight data for two or more ultrasound receivers may be useful for providing the location of applicator 240 at any given time. Velocity and/or trajectory data may derive from the position data as a function of time. It is, once again, noted that this is merely a non-limiting example.
In step S117, one or more vibration parameter(s) are established and/or adjusted in accordance with the detected velocity and/or trajectory of applicator 240. In one example, in response to a “faster” handpiece velocity, increased frequency and/or amplitudes are provided.
In
In one non-limiting example, a speed of sound is measured through the tissue is measured and this correlates with tissue softness.
In another non-limiting example, vibrations of a pre-determined amplitude are provided (for example, when a lower surface 205 of applicator 240 is in good contact with an upper surface, and the amount of current required to provide these vibrations is measured. In the event that the tissue is “hard tissue” more current would be consumed, and if the tissue is “soft” tissue less current would be consumed.
In step S125, one or more vibration parameter(s) are established and/or adjusted in accordance with the detected tissue softness. In one example, in response to a “faster” handpiece velocity, increased frequency and/or amplitudes are provided.
A Discussion of
The present inventor is now disclosing, that in some situations related to delivering pulsed RF power having a “pulse frequency”, it may be advantageous to provide mechanical vibrations with a frequency that is substantially equal to (within a given tolerance, such at 10% or 5% or 1% or 0.5%) an integral multiple (or a reciprocal of an integral multiple) of the RF pulse frequency. In some embodiments, it is possible to “synchronize” the mechanical vibrations with the RF pulses.
In one example where the direction of the mechanical vibrations is substantially perpendicular to a local upper surface of the biological tissue 200, it may be advantageous to do this such that the lower surface 205 of applicator 240 is at its “maximal low point” (i.e. providing maximum compression of biological tissue 200) at a time that the RF pulse amplitude is maximum. In some embodiments, the maximums of the mechanical vibration amplitude and the RF pulse amplitude are thus substantially “synchronized”—i.e. occur at the same time within a tolerance that is at most, for example, at most 10% or 5% or 1% or 0.5% of a shorter “period” (i.e. frequency reciprocal)—i.e. the shorter “period” of the RF power or the mechanical vibration.
The present inventor is disclosing that providing maximum compression at a time of maximum RF power may useful, for example, for (i) increasing the probability that the lower surface 205 is in contact with the upper surface 210 of biological tissue at the “most important” moment in time—i.e. when the RF pulse is at its maximum intensity; and (ii) may be useful for providing a “synergy” effect between tissue compression and administration of RF energy. In one example related to treating “deeper” layers of tissue, providing this compression may be useful for shortening, in absolute terms, the distance between the lower surface 205 of applicator 240 and the target deeper layers of tissue 210.
In the description and claims of the present application, each of the verbs, “comprise” “include” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb.
All references cited herein are incorporated by reference in their entirety. Citation of a reference does not constitute an admission that the reference is prior art.
The articles “a” and “an” are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element.
The term “including” is used herein to mean, and is used interchangeably with, the phrase “including but not limited” to.
The term “or” is used herein to mean, and is used interchangeably with, the term “and/or,” unless context clearly indicates otherwise.
The term “such as” is used herein to mean, and is used interchangeably, with the phrase “such as but not limited to”.
The present invention has been described using detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the present invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the present invention that are described and embodiments of the present invention comprising different combinations of features noted in the described embodiments will occur to persons of the art.
