Applicator for GEL application, related electronic device and GEL application system

Abstract

Disclosed is an applicator for application of a gel onto a skin surface. The applicator comprises a housing comprising a gel cavity for accommodation of a gel. The applicator comprises one or more sensors including a first sensor for provision of first sensor data. The applicator a distal end comprising a gel opening in fluid communication with the gel cavity for application of the gel. The applicator comprises processor circuitry connected to the one or more sensors. The applicator is configured to obtain first sensor data indicative of a gel application onto a skin surface from the first sensor. The applicator is configured to determine gel application data based on the first sensor data. The applicator is configured to output a gel application status according to the gel application data.

Description

[0001] APPLICATOR FOR GEL APPLICATION, RELATED ELECTRONIC DEVICE AND GEL

[0002] APPLICATION SYSTEM

[0003] The present disclosure relates to an applicator for application of a gel onto a skin surface and related electronic device. In particular, the present disclosure pertains to the field of electroencephalography and related devices / methods for simplifying and / or improving electroencephalography capture.

[0004] BACKGROUND

[0005] An electroencephalogram (EEG) is a technique of measuring the electrical activity of a brain. The EEG technique includes attaching electrodes, such as electrodes of an EEG cap, to the head of a person such that the electrodes can measure the electrical activity of the brain. In order to ensure that the electrodes can accurately measure the electrical activity of the brain, a gel is applied the skin surface where the electrode is to be attached, e.g., to reduce electrical impedance. This skin surface may also be cleaned prior to attachment of an electrode, e.g., to remove dirt, grit, grease, etc that may reduce the accuracy of measurements obtained by the electrode.

[0006] Typically, the gel application is performed by a trained medical professional as effective application of gel for electrode attachment may be difficult for non-trained persons to perform. Therefore, the gel may often be applied incorrectly and / or sub-optimally by nontrained persons, potentially reducing the quality and accuracy of the EEG.

[0007] SUMMARY

[0008] Access to trained medical professionals for performing EEG can be limited. Accordingly, there is a need for devices and / or methods which may mitigate, alleviate, or address the shortcomings existing and enable improved accuracy, robustness, and reliability of gel application, particularly when gel application is performed by a non-trained person.

[0009] Disclosed is an applicator for application of a gel onto a skin surface. The applicator comprises a housing optionally comprising a gel cavity for accommodation of a gel. The applicator comprises one or more sensors including a first sensor for provision of first sensor data. The applicator has a distal end, e.g. comprising a gel opening in fluid communication with the gel cavity for application of the gel. The applicator comprises processor circuitry connected to the one or more sensors. The applicator / processor circuitry is configured to obtain first sensor data indicative of a gel application onto a skin surface from the first sensor. The applicator is configured to determine gel application data, e.g., based on the first sensor data. The applicator is optionally configured to output the gel application data and / or a gel application status according to the gel application data.

[0010] Disclosed is an electronic device. The electronic device comprises memory circuitry, processor circuitry, and an interface. The electronic device is configured to obtain, from an applicator, one or both of sensor data and gel application data indicative of a gel application using the applicator onto a skin surface. The electronic device is configured to determine, e.g., based on the sensor data and / or the gel application data, gel application status data indicative of a status of the gel application. The electronic device is configured to provide an output indicative of the gel application status data.

[0011] Disclosed is a gel application system. The gel application system comprises an applicator according to the applicator disclosed herein. The gel application system comprises an electronic device according to the electronic device disclosed herein.

[0012] It is an advantage of the present disclosure that the disclosed applicator and related electronic device enable improved gel application to a skin surface, e.g., for electrodes of an EEG device. For example, the disclosed applicator and related electronic device may allow for improved gel application by outputting a gel application status of the gel application performed by user of the applicator. For example, the disclosed applicator and related electronic device may indicate to the user of the applicator, such as a non-trained person, whether the gel application has been satisfactorily completed, thereby enabling that the user of the applicator has performed sufficient gel application, and thereby enabling that the user of the applicator does not continue applying gel unnecessarily after the gel has been satisfactorily applied. In other words, the status of gel application is dynamically indicated to the user thereby improving gel application.

[0013] By mitigating, alleviating, or addressing the shortcomings existing, the applicator and related electronic device may enable improved quality of data obtained during EEG, such as improved accuracy, robustness, and reliability of the electrical activity measured by the electrodes, such as the electrodes of an EEG cap, e.g., due to the improved accuracy, robustness, and reliability of gel application enabled by the disclosed applicator and electronic device. In other words, the present applicator and related electronic device allows for obtaining EEGs with improved data quality and / or accuracy.

[0014] BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other features and advantages of the present disclosure will become readily apparent to those skilled in the art by the following detailed description of exemplary embodiments thereof with reference to the attached drawings, in which:

[0016] Fig. 1 illustrates an example applicator according to this disclosure,

[0017] Fig. 2 illustrates an example applicator according to the present disclosure, and

[0018] Fig. 3 illustrates an example gel application system according to the disclosure.

[0019] DETAILED DESCRIPTION

[0020] Various exemplary embodiments and details are described hereinafter, with reference to the figures when relevant. It should be noted that the figures may or may not be drawn to scale and that elements of similar structures or functions are represented by like reference numerals throughout the figures. It should also be noted that the figures are only intended to facilitate the description of the embodiments. They are not intended as an exhaustive description of the disclosure or as a limitation on the scope of the disclosure. In addition, an illustrated embodiment needs not have all the aspects or advantages shown. An aspect or an advantage described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced in any other embodiments even if not so illustrated, or if not so explicitly described.

[0021] An applicator for application of a gel onto a skin surface is disclosed. The applicator comprises a housing comprising a gel cavity for accommodation of a gel. The applicator comprises one or more sensors including a first sensor for provision of first sensor data. The applicator comprises a distal end comprising a gel opening in fluid communication with the gel cavity for application of the gel. The applicator comprises processor circuitry connected to the one or more sensors. The applicator disclosed herein can for example be seen as an applicator device to be used for application of a gel, such as onto a skin surface. The applicator may be used to spread the gel across an area of the skin surface, e.g., such that a given area of the skin surface is covered by the gel. For example, the applicator may be configured to apply the gel using a distal tip of the applicator.

[0022] The gel that the applicator may apply to the skin surface is for example a conductive gel, e.g., Conductive gel E. In some examples, the gel can be seen as a cream, paste, etc. For example, the applicator may be used to apply, such as spread, the gel to an area of skin surface where an electrode is to be applied, such as an electrode of an EEG cap. For example, the gel may be configured to reduce the electrical impedance between an electrode, e.g., of an EEG device, and the skin surface. The gel is for example located in the gel cavity of the applicator. In other words, the gel cavity comprises the gel. The gel cavity is for example a container configured to store the gel.

[0023] The housing of the applicator can for example be seen as an external housing of the applicator, such as a shell of the applicator. In some examples, the housing comprises one or more attachment points, e.g., for attachment of one or more parts of the applicator to the housing. For example, the one or more attachment points may secure one or more of the following elements of the applicator to the housing: the gel cavity, the first sensor, a second sensor, a third sensor, one or more LED lights, and an actuator. In some examples, the housing comprises one or more internal supports for supporting one or more elements of the applicator. The applicator, such as the housing of the applicator, may have an elongated form, e.g., having a proximal end and a distal end. In some examples, the housing of the applicator comprises a hand shaped form, e.g., to improve a user’s hold and / or grip on the applicator. In one or more examples, the housing has a first end and a second end. The first end of the housing may form the distal end of the applicator.

[0024] The applicator may comprise an adapter releasably attached to the first end of the housing. The adapter may form the distal end of the applicator.

[0025] A distal end of the applicator may for example be in fluid communication with the gel cavity. In other words, the gel may flow from the gel cavity to a gel opening of the distal end of the applicator and / or from the gel opening to the gel cavity (e.g., for refilling the gel cavity). For example, gel may exit the applicator via the gel opening of the distal end, e.g. in response to a user pressing a plunger at the proximal end of the applicator. In some examples, the applicator may be configured to release, e.g., based on a user input, gel from the gel opening of the distal end of the applicator. For example, the user may interact with an interface of the applicator, e.g., push a button or the piston, which in response to, the applicator may release gel from the gel opening of the distal tip of the applicator.

[0026] In some examples, the gel cavity is in fluid connection with the gel opening of the distal end of the applicator via one or more fluid channels. In some examples, the flow of gel from the gel cavity to the gel opening is controlled by a fluid flow control mechanism. For example, the flow of gel from the gel cavity to the gel opening is controlled by fluid control valve. The valve may for example be operated according to an obtained user input, such as the press of a button on the applicator.

[0027] In one or more examples, an applicator for application of a gel onto a skin surface is provided, the applicator comprising a housing comprising a gel cavity for accommodation of a gel; one or more sensors including a first sensor for provision of first sensor data; a distal end comprising a gel opening in fluid communication with the gel cavity for application of the gel; and processor circuitry connected to the one or more sensor, wherein the applicator is configured to obtain first sensor data indicative of a gel application onto a skin surface from the first sensor; determine gel application data based on the first sensor data; and output a gel application status according to the gel application data.

[0028] The applicator may provide, e.g. to the user of the applicator, a recommendation to improve gel application, thereby allowing for improved efficiency, robustness, and reliability of the gel application of the gel onto the skin surface.

[0029] The applicator may comprise an actuator configured to vibrate, wherein this vibration may facilitate improved cleaning of the skin surface and / or application of gel onto the skin surface.

[0030] The applicator comprises one or more sensors. The one or more sensors may for example comprise one or more of: a first sensor, a second sensor, and a third sensor. In one or more example applicators, the applicator comprises a first sensor, wherein the first sensor is a motion sensor configured to measure motion of the applicator, such as the distal end of the applicator. The first sensor may be arranged at or near the distal end of the applicator, e.g. within 5 cm from the distal end or within 2 cm from the distal end.

[0031] The first sensor is for example configured to obtain first sensor data. The first sensor may for example be configured to measure motion, such as movement, of the distal end of the applicator. The first sensor may for example be an accelerometer and / or a gyroscope. The first sensor data for example comprises motion data, e.g., indicative of the motion of the distal end of the applicator. The first sensor data is for example indicative of the motion of the entire applicator.

[0032] The applicator is configured to determine gel application data, e.g., based on the first sensor data. The applicator may be configured to determine gel application data, such a first movement parameter, based on one or more of first sensor data from first sensor, second sensor data from second sensor, and third sensor data from third sensor.

[0033] The gel application data may be indicative of how much the applicator has been moved e.g. in and / or during a time period. For example, the gel application may comprise a first movement parameter indicative of distal end movement of the distal end of the applicator.

[0034] The applicator is optionally configured to output a gel application status according to the gel application data. In one or more examples, to output a gel application status may comprise to output a first color, e.g. red, in accordance with the gel application data not satisfying an application criterion. In one or more examples, to output a gel application status may comprise to output a second color, e.g. green, in accordance with the gel application data satisfying an application criterion.

[0035] The applicator is optionally configured to output, e.g. transmit and / or display, the gel application data.

[0036] The skin surface is for example the surface of the skin of a subject, e.g., a person. For example, the skin surface may comprise the skin surface of the head, e.g., cranium, of the subject. The skin surface may for example be a surface of the skin of the person where an electrode, e.g., of an EEG cap, is to be applied. The gel application data is indicative of the application of gel by the applicator. For example, the gel application data may be seen as processed first sensor data, second sensor data, and / or third sensor data. The gel application status can for example be seen as the status of the gel application. For example, the gel application status may be a status indicative of whether the gel has been satisfactorily applied to the skin surface.

[0037] In one or more example applicators, the applicator comprises a user interface. In some examples, to output the gel application status comprises to output the gel application status using the user interface of the applicator. In one or more example applicators, to output a gel application status according to the gel application data comprises to activate one or more LEDs of the user interface.

[0038] The user interface may for example be a visual interface. For example, user interface may for example be configured to display one or more user interface objects, e.g., indicative of the user application status. The user interface for example comprises a screen, such as an LED screen. In some examples, the user interface comprises one or more indicator lights, e.g., for indicating the gel application status. The indicator lights may for example be LED lights, e.g., each configured to display a given colour. For example, to output the gel application status according to the gel application data may comprise one or more indicator lights switching on and / or off, e.g., according to the gel application data, such as based on gel application status data provided by the electronic device. For example, a given indicator light switching on, e.g., green LED light, may indicate to a user of the applicator that gel application has been satisfactorily performed, e.g., that the application criterion has been met. In other words, upon the application criterion being met, a given indicator light may switch on, e.g., a green LED light.

[0039] In some examples, the user interface may comprise an audio interface. For example, the user interface may comprise one or more speakers and / or buzzers. In some examples, to output the gel application status comprises to output, e.g., using one or more speakers, the gel application status as an audio signal. In other words, the one or more speakers may output an audio signal indicating the gel application status. For example, the one or more speakers of the applicator may indicate to the user of the applicator whether the gel application has been satisfactorily performed. In other words, the one or more speakers of the applicator may indicate to the user of the applicator whether the application criterion has been met. For example, the one or more speakers of the applicator may provide a spoken voice output indicative of the gel application status. In some examples, the one or more speakers may provide a sound (such as a jingle, chime, bell, etc.) to indicate that the gel application has been satisfactorily performed or that the gel application has not been satisfactorily performed. In other words, the one or more speakers may provide a sound (such as a jingle, chime, bell, etc.) to indicate whether the application criterion has been met.

[0040] In some examples, the user interface may be configured to output recommendations to the user of the applicator. For example, the screen of the user interface, such as the LED screen, may indicate to a user one or more recommendations, e.g., to improve the gel application. For example, the one or more recommendations may be based on the gel application data. For example, the applicator and / or the electronic device (such as the electronic device disclosed herein) may determine, e.g., based on the gel application data, one or more recommendations. The one or more recommendations may for example be seen as feedback to a user, e.g., such as feedback indicative of how the person using the applicator for application of gel can improve their gel application technique.

[0041] The one or more recommendations for example comprise a recommended motion for the applicator, a recommended pressure to be applied to the gel and / or the skin surface, a recommended rate of motion of the applicator, a recommendation to trigger the actuator, etc.

[0042] In some examples, the one or more recommendations comprise a cleaning recommendation. In other words, the user interface may output a recommendation indicative of a recommendation to clean the skin surface, e.g., using water and / or a cleaning solution.

[0043] In one or more example applicators, the one or more sensors comprise a second sensor for provision of second sensor data. In one or more example applicators, the second sensor is a pressure sensor configured to measure a pressure applied at the distal end of the applicator. In one or more example applicators, the applicator is configured to determine the gel application data, e.g., based on the second sensor data. The second sensor may be arranged at the first end of the housing. In one or more examples, the pressure sensor may be configured to detect a pressure applied to an adapter attached, e.g. releasably attached, at the first end of the housing.

[0044] The second sensor is for example configured to obtain second sensor data. The second sensor may for example be configured to measure pressure, e.g., force, applied by the applicator, e.g., the distal end of the applicator, to the skin surface and / or the gel. The second sensor may for example be a strain gauge pressure sensor, piezoelectric pressure sensor, capacitive pressure sensor, etc. The second sensor data for example comprises pressure data, e.g., indicative of the pressure applied by the distal end of the applicator to the skin surface and / or the gel.

[0045] The gel application data may be indicative of how much the applicator has been pressed against a surface, such as the skin, e.g. in and / or during a time period. For example, the gel application data may comprise a pressure parameter indicative of pressure applied to the distal end of the applicator. The pressure parameter may be based on the second sensor data.

[0046] In one or more example applicators, the one or more sensors comprise a third sensor for provision of third sensor data. In one or more example applicators, the third sensor is a volume sensor configured to measure a volume of dispensed gel from the applicator. In one or more example applicators, the applicator is configured to determine the gel application data, e.g., based on the third sensor data.

[0047] The third sensor is for example configured to obtain third sensor data. The third sensor may be a displacement sensor, e.g. configured to measure displacement / position of a plunger of the applicator. The third sensor may for example be configured to measure volume, such as volume of dispensed gel, e.g., from the gel opening of the applicator. In some examples, the third sensor is a volume flow sensor, such as a sensor configured to measure the volume of gel dispensed from the gel opening. The third sensor may for example be a flow rate sensor, e.g., configured to measure the flow rate of the gel via the gel opening of the applicator. The third sensor may for example be a differential flow sensor, thermal flow sensor, etc. The third sensor data for example comprises volume data, e.g., indicative of a volume of dispensed gel, e.g., from the gel opening of the applicator. In some examples, the third sensor is configured to determine the quantity, such as the volume, of gel in the gel cavity. For example, the third sensor may be configured to measure the mass of the gel cavity, such as the mass of the gel located in the gel cavity.

[0048] The gel application data may be indicative of how much gel has been dispensed from the applicator, e.g. in and / or during a time period. For example, the gel application data may comprise a pressure parameter indicative of pressure applied to the distal end of the applicator. The pressure parameter may be based on the second sensor data.

[0049] In one or more example applicators, the applicator is configured to transmit one or both of the sensor data and the gel application data to an electronic device. The applicator is for example configured transmit one or both of the sensor data and the gel application data to the electronic device disclosed herein.

[0050] In one or more example applicators, the applicator comprises an actuator configured to vibrate the distal end of the applicator.

[0051] The actuator may be configured to, e.g., upon obtaining a user input, vibrate the distal end of the applicator. For example, the user input may comprise a user pressing a button, such as a button located on and / or in the applicator. For example, the vibration of the distal end of the applicator may facilitate improved cleaning of the skin surface as the vibrating distal end of the applicator may enable improved removal of dirt, grit, grease, etc. In some examples, the vibration of the distal end of the applicator may facilitate improved gel application.

[0052] In one or more example applicators, the interface of the applicator comprises the actuator. In some examples, to output a gel application status according to the gel application data comprises to vibrate, using the actuator, the applicator, such as vibrate the housing of the actuator. For example, when the gel application has not been satisfactorily performed the actuator may perform two periods of vibration. For example, when the gel application has been satisfactorily performed the actuator may perform one periods of vibration.

[0053] In one or more examples, the applicator comprises a heating element and / or a cooling element. For example, the heating element may be used to heat the gel in the applicator, e.g., in the gel cavity. The gel in the applicator may for example be heated in order to reduce the viscosity of the gel to facilitate easier application of the gel to the skin surface. In one or more examples, the cooling element may be used to cool the gel in the applicator, e.g., in the gel cavity. The gel in the applicator may for example be cooled in order to increase the viscosity of the gel to facilitate easier application of the gel to the skin surface.

[0054] An electronic device is disclosed. The electronic device comprises memory circuitry, processor circuitry, and an interface. The electronic device is configured to obtain, from an applicator, one or both of sensor data and gel application data indicative of a gel application using the applicator onto a skin surface. The electronic device is configured to determine, e.g., based on the sensor data and / or the gel application data, gel application status data indicative of a status of the gel application. The electronic device is configured to provide an output indicative of the gel application status data.

[0055] For example, the electronic device is configured to determine, based on the sensor data and / or the gel application data from the applicator, the status of the gel application. For example, the gel application status data may be seen as information indicative of the status of the gel application, such as whether the gel application is satisfactory. For example, the gel application status data may be determined based on whether the application criterion is satisfied.

[0056] In one or more example electronic devices, to provide the output indicative of the gel application status data comprises to provide the gel application status data to the applicator and / or to a user device.

[0057] The user device may for example be a device associated with a user, such as an electronic device of a user capable of obtaining and / or providing data, such as capable of obtaining and / or providing gel application status data. For example, the user device may be an electronic device, such as a smartphone, laptop, desktop, tablet, TV, audio device, display device, etc. The user device for example comprises an interface via which an output indicative of the gel application status data may be provided.

[0058] The electronic device may for example be configured to transmit the gel application status data via a wired and / or wireless connection to the applicator and / or user device.

[0059] In one or more example electronic devices, the sensor data comprises one or more of first sensor data indicative of motion of a distal end of the applicator, second sensor data indicative of a pressure applied at the distal end of the applicator, and third sensor data indicative of a volume of dispensed gel from the applicator. In one or more example electronic devices, the gel application status data are based on one or more of the first sensor data, the second sensor data, and the third sensor data.

[0060] In other words, the status of the gel application is may be seen as being determined based on one or more of: the first sensor data, the second sensor data, and the third sensor data.

[0061] In one or more example electronic devices, to determine the gel application status data comprises to determine whether the sensor data and / or the gel application data satisfies one or more criteria.

[0062] The sensor data and the gel application data for example comprises one or more values or parameters associated with the gel application.

[0063] In one or more example electronic devices, the one or more criteria are based on one or more thresholds. In some examples, whether the sensor data and / or the gel application data satisfies the one or more criteria depends on whether one or more parameters / values of the sensor data and / or the gel application data are greater than (or equal to) or less (or equal to) than the one or more thresholds.

[0064] The one or more criteria for example comprise one or more of: one or more first criteria, one or more second criteria, one or more third criteria, and one or more fourth criteria.

[0065] The one or more criteria are for example respectively based on: one or more first thresholds, one or more second thresholds, one or more third thresholds, and one or more fourth thresholds.

[0066] The one or more first criteria are for example associated with data obtained from the first sensor, e.g., first sensor data, such as motion data.

[0067] The first sensor data for example comprises one or more parameters / values indicative of the motion of the distal end of the applicator. The one or more first criteria are for example based on one or more first thresholds. In some examples, to determine whether the first sensor data satisfies the one or more first thresholds comprises to determine whether one or more values of the first sensor data are greater than or equal to one or more of the one or more first thresholds.

[0068] For example, to determine whether the first sensor data satisfies a given first criterion of the one or more first criteria, the electronic device may determine whether one or more values of the first sensor data are greater than or equal to the first threshold associated with that given first criterion.

[0069] For example, when one or more values of the first sensor data are greater than or equal to a given first threshold associated with the given first criterion, the given first criterion can be seen as satisfied by the first sensor data. For example, when one or more values of the first sensor data are less than the given first threshold associated with the given first criterion, the given first criterion can be seen as not being satisfied by the first sensor data.

[0070] In some examples, a given first criterion of the one or more first criteria may be satisfied when one or more values of the first sensor data (e.g., over a given time period) are between two of the one or more first thresholds associated with the given first criterion. In other words, a given first criterion may for example be satisfied when one or more values of the first sensor data are within a given range, such as a range defined by two of the one or more first thresholds.

[0071] The one or more second criteria are for example associated with data obtained from the second sensor, e.g., second sensor data, such as pressure data.

[0072] The second sensor data for example comprises one or more values indicative of the pressure applied at the distal end of the applicator The one or more second criteria are for example based on one or more second thresholds. In some examples, to determine whether the second sensor data satisfies the one or more second thresholds comprises to determine whether one or more values of the second sensor data are greater than or equal to the one or more second thresholds.

[0073] For example, to determine whether the second sensor data satisfies a given second criterion of the one or more second criteria, the electronic device may determine whether one or more values of the second sensor data are greater than or equal to the second threshold that is associated with that given second criterion. For example, when one or more values of the second sensor data are greater than or equal to a given second threshold associated with the given second criterion, the given second criterion can be seen as satisfied by the second sensor data. For example, when one or more values of the second sensor data are less than the given second threshold associated with the given second criterion, the given second criterion can be seen as not being satisfied by the second sensor data.

[0074] In some examples, a given second criterion of the one or more second criteria may be satisfied when one or more values of the second sensor data (e.g., over a given time period) are between two of the one or more second thresholds associated with the given second criterion. In other words, a given second criterion may for example be satisfied when one or more values of the second sensor data are within a given range, such as a range defined by two of the one or more second thresholds.

[0075] The one or more third criteria are for example associated with data obtained from the third sensor, e.g., third sensor data, such as volume data.

[0076] The third sensor data for example comprises one or more values indicative of the volume of dispensed gel from the applicator. The one or more third criteria are for example based on one or more third thresholds. In some examples, to determine whether the third sensor data satisfies the one or more third thresholds comprises to determine whether one or more values of the third sensor data are greater than or equal to the one or more third thresholds.

[0077] For example, to determine whether the third sensor data satisfies a given third criterion of the one or more third criteria, the electronic device may determine whether one or more values of the third sensor data are greater than or equal to the third threshold that is associated with that given third criterion. For example, when one or more values of the third sensor data are greater than or equal to a given third threshold associated with the given third criterion, the given third criterion can be seen as satisfied by the third sensor data. For example, when one or more values of the third sensor data are less than the given third threshold associated with the given third criterion, the given third criterion can be seen as not being satisfied by the third sensor data. In some examples, a given third criterion of the one or more third criteria may be satisfied when one or more values of the third sensor data (e.g., over a given time period) are between two of the one or more third thresholds associated with the given third criterion. In other words, a given third criterion may for example be satisfied when one or more values of the third sensor data are within a given range, such as a range defined by two of the one or more third thresholds.

[0078] The one or more fourth criteria are for example associated with the gel application data.

[0079] The gel application data for example comprises one or more parameters / values determined based on one or more of: the first sensor data, the second sensor data, and the third sensor data. The one or more fourth criteria are for example based on one or more fourth thresholds. In some examples, to determine whether the gel application data satisfies the one or more fourth thresholds comprises to determine whether one or more values of the gel application data are greater than or equal to the one or more fourth thresholds.

[0080] For example, to determine whether the gel application data satisfies a given fourth criterion of the one or more fourth criteria, the electronic device may determine whether one or more values of the gel application data are greater than or equal to the fourth threshold that is associated with that given fourth criterion. For example, when one or more values of the gel application data are greater than or equal to a given fourth threshold associated with the given fourth criterion, the given fourth criterion can be seen as satisfied by the fourth sensor data. For example, when one or more values of the gel application data are less than the given fourth threshold associated with the given fourth criterion, the given fourth criterion can be seen as not being satisfied by the gel application data.

[0081] In some examples, a given fourth criterion of the one or more fourth criteria may be satisfied when one or more values of the gel application data (e.g., over a given time period) are between two of the one or more fourth thresholds associated with the given fourth criterion. In other words, a given fourth criterion may for example be satisfied when one or more values of the gel application data are within a given range, such as a range defined by two of the one or more fourth thresholds. In one or more example electronic devices, the electronic device is configured to obtain electrode data from an electroencephalogram, EEG, device. In one or more example electronic devices, the electronic device is configured to determine the gel application status data based on the electrode data. For example, the gel application status data may be set to a value indicating satisfactory gel application in accordance with electrode data indicating a desired impedance between electrodes of the EEG device.

[0082] In some examples, the EEG device is an EEG cap, such as an EEG cap configured to be placed on the head of a subject, e.g., a patient. The subject may for example be human or non-human. The EEG device is for example configured to measure the brain waves of the subject. The EEG device for example comprises one or more electrodes. The one or more electrodes of the EEG device are for example configured to be applied to the skin surface, such as the skin surface of gel application by the applicator.

[0083] The EEG device is for example configured to obtain, using the one or more electrodes, electrode data. The electrode data for example comprises impedance data, e.g., indicative of the electrical impedance at the contact patch of the electrode to the skin surface.

[0084] In one or more example electronic devices, to determine the gel application status data comprises to determine whether the electrode data satisfies an application criterion.

[0085] In one or more example electronic devices, the application criterion is based on an impedance threshold. In some examples, whether the impedance data satisfies the application criterion depends on whether the impedance data is greater than (or equal to) or less than the impedance threshold. For example, when the impedance data, such as one or more values of the impedance data, is greater than the impedance threshold, the application criterion can be seen as not being satisfied by the impedance data. For example, when the impedance data, such as one or more values of the impedance data, is less than the impedance threshold, the application criterion can be seen as being satisfied by the impedance data.

[0086] The impedance threshold may for example be any value between 1 and 40, such as 1 and 40 kiloohms. The impedance threshold may for example be a value of 10, such as 10 kiloohms. For example, when the impedance data, such as one or more values of the impedance data, is less than 10 kiloohms, the application criterion can be seen as being satisfied by the impedance data.

[0087] For example, when the application criterion is satisfied by the electrode data, the gel application may be seen as satisfactorily completed, e.g., for the given area of the skin surface that the electrode is affixed to, such as secured to. For example, when the application criterion is not satisfied by the electrode data, the gel application may be seen as not being satisfactorily completed, e.g., for the given area of the skin surface that the electrode is affixed to.

[0088] The figures are schematic and simplified for clarity, and they merely show details which aid understanding the disclosure, while other details have been left out. Throughout, the same reference numerals are used for identical or corresponding parts.

[0089] Fig. 1 illustrates an example applicator according to this disclosure. The applicator 1 is an example applicator, such as an example applicator of the applicator disclosed herein.

[0090] The applicator 1 comprises a housing 4 having a first end 6 and comprising a gel cavity 8 for accommodation of a gel 8A. The applicator comprises one or more sensors including a first sensor 10, e.g. an accelerometer and / or a gyroscope, for provision of first sensor data 10A. The applicator 1 has a distal end 12 comprising a gel opening 14 in fluid communication via fluid channel 16 with the gel cavity 8 for application of gel 8A arranged in the gel cavity. The applicator 1 comprises processor circuitry 20 connected to the one or more sensors. The processor circuitry 20 may for example comprise a microcontroller (MC, UC, or pC) or microcontroller unit (MCU).

[0091] The applicator 1 is configured to obtain first sensor data 10A indicative of a gel application onto a skin surface from the first sensor 10 being a motion sensor.

[0092] The applicator 1 optionally comprises a second sensor 22, e.g. a pressure sensor configured to measure a pressure applied at the distal end of the applicator, for provision of second sensor data 22A. The second sensor 22 may for example be a strain gauge pressure sensor, piezoelectric pressure sensor, capacitive pressure sensor, etc. The second sensor data for example comprises pressure data, e.g., indicative of the pressure applied by the distal end of the applicator to the skin surface and / or the gel. The applicator 1 optionally comprises a third sensor 24, e.g. a volume sensor configured to measure a volume of dispensed gel from the applicator for provision of third sensor data 24A. The third sensor 24 may for example be a flow rate sensor, e.g., configured to measure the flow rate of the gel 8A via the gel opening 14. The third sensor 24 may for example be a differential flow sensor, thermal flow sensor, etc. The third sensor data 24A for example comprises volume data, e.g., indicative of a volume of dispensed gel, e.g., from the gel opening 14. The third sensor 24 may be a displacement sensor.

[0093] In one or more example applicators, the processor circuitry 20 / applicator 1 is configured to determine the gel application data based on the first sensor data 10A, the second sensor data 22A, and the third sensor data 24A.

[0094] The applicator 1 is optionally configured to output a gel application status according to the gel application data.

[0095] In some examples, the flow of gel 8A from the gel cavity 8 to the gel opening 14 is controlled by a fluid flow control mechanism, such as a plunger and / or a fluid control valve (not shown).

[0096] In one or more example applicators, the applicator 1 is configured to transmit one or both of the sensor data 10A, 22A, 24A and the gel application data to an electronic device. In some examples, the applicator 1 provides, such as transmit, one or more of the first sensor data, the second sensor data, the third sensor data, and the gel application data to an electronic device, such as the electronic device 300 as shown in Fig. 2. In one or more examples applicators, the applicator 1 comprises an interface, such as an interface configured to transmit data. For example, to transmit one or both of the sensor data and the gel application data to an electronic device comprises to transmit, using an interface of the applicator 1 , one or both of the sensor data and the gel application data to an electronic device.

[0097] The first sensor 10 for example provides, e.g., via a wired connection, the first sensor data 10A to the processor circuitry 20. The second sensor 22 for example provides, e.g., via a wired connection, the second sensor data 22A to the processor circuitry 20. The third sensor 24 for example provides, e.g., via a wired connection, the third sensor data 24A to the processor circuitry 20. The applicator 1 may comprise an actuator 26 configured to vibrate the distal end 12 of the applicator 1 . The actuator 26 may be configured to be operated using the processor circuitry 20. For example, a user input, such as a user pressing a button (not shown) of the applicator 1 , may initiate a triggering signal to be provided to the actuator 26 thereby triggering the actuation of the actuator 26.

[0098] The applicator 1 may comprise a user interface, and to output a gel application status according to the gel application data optionally comprises to activate one or more indicator lights, such as LEDs, of the user interface. The user interface may for example comprise a display 28, such as an LED display. For example, to activate one or more LEDs of the user interface may comprise to activate one or more LED lights of the display 28. The user interface may for example comprise one or more indicator lights 30A, 30B, 30C, such as LED lights. For example, to activate one or more LEDs of the user interface may comprise to activate one or more LED lights of the indicator lights 30A, 30B, 30C.

[0099] The applicator 1 optionally comprises a transceiver and / or a wired connector (not shown) for wireless and / or wired connection to an electronic device of gel application system e.g. as described herein.

[0100] Fig. 2 illustrates an applicator 1 A. The applicator 1 A comprises a plunger 32 configured to press gel 8A out of gel cavity 8 via gel opening 14. The applicator 1A comprises an adapter 34 releasably attached to the first end 6 of the housing 4. A first end 36 of the adapter 34 forms the distal end 12 of the applicator 1 A and comprises the gel opening 14.

[0101] The adapter 34 is for example an attachable needle releasably attached to the housing 4. For example, the adapter 34 may be a disposable needle and / or a replaceable needle releasably attached to the housing 4. The applicator comprises a flange 38, such as a finger flange to provide support to a user pressing the plunger 32.

[0102] The applicator 1A has a distal end 12 comprising a gel opening 14 in fluid communication, via fluid channel 16, with the gel cavity 8 for application of the gel 8A arranged in the gel cavity 8. The adapter 34 comprises a part of the fluid channel 16, thereby enabling the gel opening 14 to be in fluid communication with the gel cavity 8 such that gel 8A can be provided from the gel opening 14 of applicator 1A. The applicator 1A comprises a first sensor 10. The first sensor 10 is attached to or arranged in the housing 4 of applicator 1A. The first sensor 10 is configured to measure motion, e.g., of the distal end of the applicator 1A. For example, the first sensor 10 is configured to measure rotation and / or tilt of the applicator 1A.

[0103] The second sensor 22 is arranged at the first end of the housing 4 and is configured to detect a pressure applied to the distal end 12 of the applicator 1A.

[0104] The applicator 1A comprises a module 21 attached to the housing 4. The module 21 comprises processor circuitry 20. The processor circuitry may for example comprise a microcontroller (MC, UC, or pC) or microcontroller unit (MCU).

[0105] The applicator 1A is configured for wireless, e.g., Bluetooth Low Energy (BLE) and / or WiFi, communication with an electronic device as disclosed herein for transmitting one or more of sensor data 10A, 24A, 26A and gel application data 48. The module 21 for example comprises an interface configured for wireless communication, e.g., BLE and / or WiFi.

[0106] The module 21 comprises a power supply, such as a battery. The battery is for example rechargeable. In some examples, the module 21 comprises one or more battery slots configured to draw power from one or more replaceable batteries. In some examples, the applicator 1A is powered via a wired connection.

[0107] The third sensor 24 of applicator 1 A is a displacement sensor for provision of third sensor data indicative of displacement / position of the plunger 32. In other words, the third sensor data 26A may comprise displacement data from which a volume parameter can be determined, such as calculated.

[0108] One or more of: the first sensor 10, the second sensor 22, and the third sensor 24, are powered via connection to the power supply of module 21 .

[0109] The applicator 1A optionally comprises a fourth indicator light 30D. In some examples, to output a gel application status according to the gel application data comprises to activate the fourth indicator light 30D, e.g., the fourth indicator light being a part of a user interface of the applicator 1A. The fourth indicator light 30D is for example an LED light. The fourth light indicator 30D is for example controlled using the processor circuitry, e.g., of the module 21.

[0110] Fig. 3 is a diagram illustrating schematically an example gel application system 2 according to the disclosure. The gel application system 2 comprises an applicator as disclosed herein, such as applicator 1 , 1A, an electronic device 40 as disclosed herein, and an EEG device 50. The electronic device 40 comprises memory circuitry 42, processor circuitry 44, and an interface 46.

[0111] The EEG device 50 comprises a data collector 52 and one or more electrodes 54 connected to the data collector 52. The one or more electrodes 54 of the EEG device 50 are optionally arranged in an EEG cap 55 and for example applied to the skin surface of a subject 56, e.g., a patient. The data collector 52 obtains and transmits (wirelessly and / or wired) electrode data 58 to the electronic device 40.

[0112] The electronic device 40 is configured, e.g. via wired and / or wireless connection, to obtain, e.g., using interface 46, from the applicator 1 , 1 A, one or both of sensor data, such as 10A, 24A, 26A, and gel application data 48 indicative of a gel application using the applicator 1 , 1 A onto the skin surface of subject 56.

[0113] The electronic device 40 is configured to determine, e.g., using the memory circuitry 42 and / or processor circuitry 44 and based on one or more of first sensor data 10A, second sensor data 24A, third sensor data 26A, gel application data 48 and electrode data 58, gel application status data indicative of a status of the gel application; and provide, e.g., using interface 46, such as a display 46A and / or a loudspeaker 46B, an output indicative of the gel application status data.

[0114] The operations of the electronic device 40 may be embodied in the form of executable logic routines (e.g., lines of code, software programs, etc.) that are stored on a non- transitory computer readable medium (e.g., the memory circuitry 42) and are executed by the processor circuitry 44).

[0115] Furthermore, the operations of the electronic device 40 may be considered a method that the electronic device 40 is configured to carry out. Also, while the described functions and operations may be implemented in software, such functionality may as well be carried out via dedicated hardware or firmware, or some combination of hardware, firmware and / or software.

[0116] The memory circuitry 42 may be one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, a random access memory (RAM), or other suitable device. In a typical arrangement, the memory circuitry 42 may include a non-volatile memory for long term data storage and a volatile memory that functions as system memory for the processor circuitry 44. The memory circuitry 42 may exchange data with the processor circuitry 44 over a data bus. Control lines and an address bus between the memory circuitry 42 and the processor circuitry 44 also may be present (not shown in Fig. 3). The memory circuitry 42 is considered a non-transitory computer readable medium.

[0117] The memory circuitry 42 may be configured to store first sensor data, second sensor data, third sensor data, gel application data, gel application status data, one or more criteria, electrode data, and / or the application criterion in a part of the memory 42.

[0118] In one or more example electronic devices, to provide the output indicative of the gel application status data comprises to provide, such as transmit, the gel application status data 60 to the applicator 1 , 1 A. In some examples, the applicator 1 , 1 A may output, e.g., based on the gel application status data, a gel application status.

[0119] Examples of the applicator and related electronic device according to the disclosure are set out in the following items:

[0120] Item 1 . An applicator for application of a gel onto a skin surface, the applicator comprising: a housing comprising a gel cavity for accommodation of a gel; one or more sensors including a first sensor for provision of first sensor data; a distal end comprising a gel opening in fluid communication with the gel cavity for application of the gel; and processor circuitry connected to the one or more sensor, wherein the applicator is configured to: obtain first sensor data indicative of a gel application onto a skin surface from the first sensor; determine gel application data based on the first sensor data; and output a gel application status according to the gel application data.

[0121] Item 2. Applicator according to item 1 , wherein the first sensor is a motion sensor configured to measure motion of the distal end of the applicator.

[0122] Item 3. Applicator according to any one of items 1-2, wherein the one or more sensors comprise a second sensor for provision of second sensor data, wherein the second sensor is a pressure sensor configured to measure a pressure applied at the distal end of the applicator, and wherein the applicator is configured to determine the gel application data based on the second sensor data.

[0123] Item 4. Applicator according to any one of items 1-3, wherein the one or more sensors comprise a third sensor for provision of third sensor data, wherein the third sensor is a volume sensor configured to measure a volume of dispensed gel from the applicator, and wherein the applicator is configured to determine the gel application data based on the third sensor data.

[0124] Item 5. Applicator according to any one of items 1-4, wherein the applicator is configured to transmit one or both of the sensor data and the gel application data to an electronic device.

[0125] Item 6. Applicator according to any one of items 1-5, wherein the applicator comprises an actuator configured to vibrate the distal end of the applicator.

[0126] Item 7. Applicator according to any one of items 1-6, the applicator comprising a user interface, and wherein to output a gel application status according to the gel application data comprises to activate one or more LEDs of the user interface.

[0127] Item 8. An electronic device comprising memory circuitry, processor circuitry, and an interface, wherein the electronic device is configured to: obtain, from an applicator, one or both of sensor data and gel application data indicative of a gel application using the applicator onto a skin surface; determine, based on the sensor data and / or the gel application data, gel application status data indicative of a status of the gel application; and provide an output indicative of the gel application status data.

[0128] Item 9. Electronic device according to item 8, wherein to provide the output indicative of the gel application status data comprises to provide the gel application status data to the applicator and / or to a user device.

[0129] Item 10. Electronic device according to any one of items 8-9, wherein the sensor data comprises one or more of first sensor data indicative of motion of a distal end of the applicator, second sensor data indicative of a pressure applied at the distal end of the applicator, and third sensor data indicative of a volume of dispensed gel from the applicator, and wherein the gel application status data are based on one or more of the first sensor data, the second sensor data, and the third sensor data.

[0130] Item 11. Electronic device according to any one of items 8-10, wherein to determine the gel application status data comprises to determine whether the sensor data and / or the gel application data satisfies one or more criteria.

[0131] Item 12. Electronic device according to any one of items 8-11 , wherein the electronic device is configured to obtain electrode data from an electroencephalogram, EEG, device, and determine the gel application status data based on the electrode data.

[0132] Item 13. Electronic device according to item 12, wherein to determine the gel application status data comprises to determine whether the electrode data satisfies an application criterion.

[0133] Item 14. A gel application system comprising an applicator according to any one of items 1-7 and an electronic device according to any one of items 8-13.

[0134] The use of the terms “first”, “second”, “third” and “fourth”, “primary”, “secondary”, “tertiary” etc. does not imply any particular order, but are included to identify individual elements. Moreover, the use of the terms “first”, “second”, “third” and “fourth”, “primary”, “secondary”, “tertiary” etc. does not denote any order or importance, but rather the terms “first”, “second”, “third” and “fourth”, “primary”, “secondary”, “tertiary” etc. are used to distinguish one element from another. Note that the words “first”, “second”, “third” and “fourth”, “primary”, “secondary”, “tertiary” etc. are used here and elsewhere for labelling purposes only and are not intended to denote any specific spatial or temporal ordering. Furthermore, the labelling of a first element does not imply the presence of a second element and vice versa.

[0135] It may be appreciated that the figures comprise some circuitries or operations which are illustrated with a solid line and some circuitries or operations which are illustrated with a dashed line. The circuitries or operations which are comprised in a solid line are circuitries or operations which are comprised in the broadest example embodiment. The circuitries or operations which are comprised in a dashed line are example embodiments which may be comprised in, or a part of, or are further circuitries or operations which may be taken in addition to the circuitries or operations of the solid line example embodiments. It should be appreciated that these operations need not be performed in order presented. Furthermore, it should be appreciated that not all of the operations need to be performed. The exemplary operations may be performed in any order and in any combination.

[0136] It is to be noted that the word “comprising” does not necessarily exclude the presence of other elements or steps than those listed.

[0137] It is to be noted that the words “a” or “an” preceding an element do not exclude the presence of a plurality of such elements.

[0138] It is to be noted that the term “indicative of” may be seen as “associated with”, “related to”, “descriptive of’, “characterizing”, and / or “defining”. The terms “indicative of”, “associated with”, “related to”, “descriptive of”, “characterizing”, and “defining” can be used interchangeably. The term “indicative of” can be seen as indicating a relation. For example, weight data indicative of weight may comprise one or more weight parameters.

[0139] It is to be noted that the word "based on" may be seen as “as a function of” and / or “derived from”. The terms “based on” and “as a function of” can be used interchangeably. For example, a parameter determined “based on” a data set can be seen as a parameter determined “as a function of’ the data set. In other words, the parameter may be an output of one or more functions with the data set as an input. A function may be characterizing a relation between an input and an output, such as mathematical relation, a database relation, a hardware relation, logical relation, and / or other suitable relations.

[0140] It should further be noted that any reference signs do not limit the scope of the claims, that the exemplary embodiments may be implemented at least in part by means of both hardware and software, and that several “means”, “units” or “devices” may be represented by the same item of hardware.

[0141] The various exemplary methods, devices, and systems described herein are described in the general context of method steps or processes, which may be implemented in one aspect by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage devices including, but not limited to, Read Only Memory (ROM), Random Access Memory (RAM), compact discs (CDs), digital versatile discs (DVD), etc. Generally, program circuitries may include routines, programs, objects, components, data structures, etc. that perform specified tasks or implement specific abstract data types. Computer-executable instructions, associated data structures, and program circuitries represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

[0142] Although features have been shown and described, it will be understood that they are not intended to limit the claimed disclosure, and it will be made obvious to those skilled in the art that various changes and modifications may be made without departing from the scope of the claimed disclosure. The specification and drawings are, accordingly to be regarded in an illustrative rather than restrictive sense. The claimed disclosure is intended to cover all alternatives, modifications, and equivalents. LIST OF REFERENCES

[0143] 1 , 1 A applicator

[0144] 2 gel application system

[0145] 4 housing

[0146] 6 first end of housing

[0147] 8 gel cavity

[0148] 8A gel

[0149] 10 first sensor

[0150] 10 first sensor data

[0151] 12 distal end of applicator

[0152] 14 gel opening

[0153] 16 fluid channel

[0154] 20 processor circuitry

[0155] 21 module

[0156] 22 second sensor

[0157] 22A second sensor data

[0158] 24 third sensor

[0159] 24A third sensor data

[0160] 26 actuator

[0161] 28 display

[0162] 30A first indicator light

[0163] 30B second indicator light

[0164] 30C third indicator light

[0165] 30D fourth indicator light

[0166] 32 plunger

[0167] 34 adapter 36 first end

[0168] 38 flange

[0169] 40 electronic device

[0170] 42 memory circuitry 44 processor circuitry

[0171] 46 interface

[0172] 46A display

[0173] 46B loudspeaker

[0174] 48 gel application data 50 EEG device

[0175] 52 data collector

[0176] 54 electrode

[0177] 55 EEG cap

[0178] 56 subject 58 electrode data

[0179] 60 gel application status data

Claims

CLAIMS1 . An applicator for application of a gel onto a skin surface, the applicator comprising: a housing comprising a gel cavity for accommodation of a gel; one or more sensors including a first sensor for provision of first sensor data; a distal end comprising a gel opening in fluid communication with the gel cavity for application of the gel; and processor circuitry connected to the one or more sensor, wherein the applicator is configured to: obtain first sensor data indicative of a gel application onto a skin surface from the first sensor; determine gel application data based on the first sensor data; and output a gel application status according to the gel application data.

2. Applicator according to claim 1 , wherein the first sensor is a motion sensor configured to measure motion of the distal end of the applicator.

3. Applicator according to any one of claims 1-2, wherein the one or more sensors comprise a second sensor for provision of second sensor data, wherein the second sensor is a pressure sensor configured to measure a pressure applied at the distal end of the applicator, and wherein the applicator is configured to determine the gel application data based on the second sensor data.

4. Applicator according to any one of claims 1-3, wherein the one or more sensors comprise a third sensor for provision of third sensor data, wherein the third sensor is a volume sensor configured to measure a volume of dispensed gel from the applicator, and wherein the applicator is configured to determine the gel application data based on the third sensor data.

5. Applicator according to any one of claims 1-4, wherein the applicator is configured to transmit one or both of the sensor data and the gel application data to an electronic device.

6. Applicator according to any one of claims 1-5, wherein the applicator comprises an actuator configured to vibrate the distal end of the applicator.

7. Applicator according to any one of claims 1-6, the applicator comprising a user interface, and wherein to output a gel application status according to the gel application data comprises to activate one or more LEDs of the user interface.

8. An electronic device comprising memory circuitry, processor circuitry, and an interface, wherein the electronic device is configured to: obtain, from an applicator, one or both of sensor data and gel application data indicative of a gel application using the applicator onto a skin surface; determine, based on the sensor data and / or the gel application data, gel application status data indicative of a status of the gel application; and provide an output indicative of the gel application status data.

9. Electronic device according to claim 8, wherein to provide the output indicative of the gel application status data comprises to provide the gel application status data to the applicator and / or to a user device.

10. Electronic device according to any one of claims 8-9, wherein the sensor data comprises one or more of first sensor data indicative of motion of a distal end of the applicator, second sensor data indicative of a pressure applied at the distal end of the applicator, and third sensor data indicative of a volume of dispensed gel from the applicator, and wherein the gel application status data are based on one or more of the first sensor data, the second sensor data, and the third sensor data.

11. Electronic device according to any one of claims 8-10, wherein to determine the gel application status data comprises to determine whether the sensor data and / or the gel application data satisfies one or more criteria.

12. Electronic device according to any one of claims 8-11 , wherein the electronic device is configured to obtain electrode data from an electroencephalogram, EEG, device, and determine the gel application status data based on the electrode data.

13. Electronic device according to claim 12, wherein to determine the gel application status data comprises to determine whether the electrode data satisfies an application criterion.

14. A gel application system comprising an applicator according to any one of claims 1-7 and an electronic device according to any one of claims 8-13.

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