Abstract: According to one aspect of the invention, there is provided a method for monitoring hemodynamics, comprising the steps of: acquiring information on a posture of a first subject wearing a monitoring device; estimating a motion artifact predicted to be included in a spectroscopic measurement signal from the first subject which is measured by the monitoring device, with reference to the acquired information on the posture of the first subject, and a motion artifact estimation model for defining a correlation between a posture of at least one subject and a motion artifact occurring in a signal measured from the at least one subject; and removing the estimated motion artifact from the measurement signal from the first subject.

Abstract: A method and an apparatus for separating a composite signal into a plurality of signals is described. A signal processor receives a composite signal and separates a composite signal into separate output signals. Feedback from one or more of the output signals is provided to a configuration module that configures the signal processor to improve a quality of the output signals. In one embodiment, calibration data from multiple calibration data sets is used to configure the demodulation of the composite signal into separate output signals.

Abstract: A system, wearable device, and method include a light emitter configured to emit light at a first wavelength of between approximately 900 and 1000 nanometers and at a second wavelength of approximately 1350 nanometers, a first light detector spaced at a first distance from the light emitter, and a second light detector spaced at a second distance from the light emitter, the second distance approximately twice the first distance. At least one of hydration and glycogen of muscle tissue is determinable based on a relationship between backscatter light from the muscle tissue as detected by the second light detector and backscatter light from non-muscle tissue as detected by the first light detector.

Abstract: This disclosure relates to selection of optimum channel in twin radars for efficient detection of cardiopulmonary signal rates. State-of-the-art solutions involve use of IQ (In-phase and Quadrature) channel radar which need continuous calibration. Distance of the radar from a subject being monitored affects performance. The present disclosure enables enhanced cardiopulmonary signal rate monitoring using a time domain approach, wherein only the data from signal reflected off the radar is considered. The solution is also time window adaptive. Signal property and radar physics-based methods have been implemented for selecting an optimum channel in twin radars thereby enhancing detection of respiration rate and breath rate.

Abstract: A sensor device includes a sensor array including a plurality of photodiodes configured to generate current signals in response to light, an encoder configured to encode the current signals to generate a plurality of analog signals and output the plurality of analog signals sequentially, a signal processing module configured to process the analog signals, received from the encoder, to generate digital signals, and a decoder configured to decode the digital signals, received from the signal processing module, to generate a plurality of data signals corresponding to the current signals.

Abstract: An illustrative optical measurement system may include a wearable assembly comprising a plurality of modules each configured to fit within a different slot of the wearable assembly. The plurality of modules may include a module that comprises first and second light sources each configured to emit light directed at a target and a set of detectors configured to detect arrival times for photons of the light emitted by the first and second light sources. A ratio of a total number of the detectors to a total number of the light sources is at least two to one.

Abstract: Pulse oximeter systems are described that detect an oxygen level of a user and/or monitor a user's heart rate. The pulse oximeter systems are configured to provide an alert when a user's detected oxygen level decreases below an established oxygen level, and/or when a user's heart rate decreases below a lower threshold value and/or increases above an upper threshold value. For example, an alert may be provided when a user's detected oxygen level decreases by more than about five percent (5%) of an established oxygen level. In some instances, an operator can set a level at which an alert will be provided.

Abstract: A device comprising a piece of planar substrate embedded with two sensors and two emitters. The substrate has a generally planar surface for application onto the wearer's body part. The emitters and sensors are shown to be arranged in such a way that no subset of any two emitters and one sensor, or subset of any two emitters and one sensor, forms a straight line, which prevents the two sensors from detecting the same noise caused by the same wearer movements.

Abstract: An in-ear hearing device includes a light source configured to emit light, a photodetector configured to detect the emitted light after the emitted light passes through tissue of a subject, a spout; an audio receiver configured to deliver a sound to the subject through the spout, and a dome configured to conform to a shape of a subject's ear canal when the hearing device is in the ear canal. An output of the light source and an input of the photodetector are separated by the dome, and the dome absorbs and/or reflects at least part of the emitted light. The photodetector may be a forward biased photodiode. The sensor device can be realized with power levels, circuitry components, and in package sizes, of hearing devices.

Abstract: A flexible printed circuit board (FPCA) of a brain computer interface (BCI) module is configured to interconnect a plurality of emitter assemblies and a plurality of detector assemblies of the BCI module. The FPCA comprises a connector portion for connecting the FPCA to a controller of the BCI module, a plurality of rigid sections, a plurality of flexible sections. A first subset of rigid sections is configured to mount the plurality of emitter assemblies. A second subset of rigid sections is configured to mount the plurality of detector assemblies. Each flexible section is configured to attach the two or more rigid sections of the plurality of rigid sections to each other. The plurality of flexible sections allows the plurality of emitter assemblies and the plurality of detector assemblies to stretch to conform to a head of a user.

Abstract: A medical photometer includes a signal producing section that produces a first control signal to emit a first light having a first wavelength, a second control signal to emit a second light having a second wavelength, a third control signal to emit a third light having a third wavelength, and a fourth control signal to emit a fourth light having a fourth wavelength, a signal acquiring section that acquires a first to fourth intensity signals, a processor, and a memory that stores instructions. In the medical photometer, the first wavelength and the second wavelength are selected as two wavelengths at each of which an extinction coefficient of blood is a first value. The third wavelength and the fourth wavelength are selected as two wavelengths at each of which the extinction coefficient of the blood is a second value which is different from the first value.

Abstract: The present invention relates in particular to the field of anesthesia and to a method for real-time evaluation of the mean arterial pressure of a patient from plethysmography measurements. It also relates to a method for treating a patient comprising by continuously evaluating the mean arterial pressure of the patient, based on values continuously calculated by plethysmography.

Abstract: A monitoring device configured to be attached to a body of a subject includes a sensor having at least one optical emitter and at least one optical detector, and a processor coupled to the sensor. The processor is configured to instruct the at least one optical emitter to emit a different wavelength of light into the body of the subject during each of a series of respective time intervals. The processor is configured to measure a respective different physiological parameter from signals produced by the at least one optical detector upon receiving light from the body of the subject during each of the respective time intervals.

Abstract: The present disclosure provides alert implants that comprise a medical device and an implantable reporting processor (IRP), where one example of such a medical device includes a component for a total knee arthroplasty (TKA) such as a tibial extension, a femoral component for hip replacements, a breast implant, a distal rod for arm or leg breakage repair, a scoliosis rod, a dynamic hip screw, a spinal interbody spacer, and tooling and methods that may be used to form the alert implant, and uses of such alert implants in the health maintenance of patients who receive the implant.

Abstract: This disclosure relates to wireless electronics designed for use within the oral cavity to measure biological or chemical variables, including pH or analyte concentrations, and transmit the measurements. More particularly, the disclosure relates to a wearable intraoral sensor comprising sensing electronics arranged within a flexible circuit mounted onto a molar band, a wireless transmission unit coupled to the sensing electronics and configured to wirelessly transmit electrical data signals to a receiver outside of the oral cavity, and a power source operably coupled to the sensing electronics and wireless transmission unit. The wearable intraoral sensor can be installed around a tooth and continually measure and wirelessly transmit measurement data for extended periods of time without user action.

Abstract: For localizing gingival inflammation within a user's mouth the following steps are carried out using an oral care device (10): (i) sequentially emitting (520) light by a plurality of light sources (48) in a first sequential pattern, wherein at least some of the plurality of light sources are configured to emit light of different wavelengths; (ii) sequentially emitting (530) light in a second sequential pattern which is the reverse of the first sequential pattern; (iii) obtaining (540), by a light detector (40), reflectance measurements to generate first reflectance data from light emitted in the first sequential pattern, and to generate second reflectance data from light emitted in the second sequential pattern; (iv) averaging (550), by a controller (30), first reflectance data and second reflectance data for each wavelength to generate averaged reflectance data; and (v) determining (570), using the averaged reflectance data, whether gingiva at the location is inflamed.

Abstract: A biological data measurement device includes a substrate disposed at a position spaced a predetermined distance from a body surface of a living organism as a measuring object via a support member so that an air layer is formed between the substrate and the body surface. The substrate is provided with a temperature measurement device including an infrared thermometer for measuring a body surface temperature Tsk of the body surface and a substrate thermometer for measuring a substrate temperature Tsub of the substrate. The temperature measurement device measures the body surface temperature Tsk and the substrate temperature Tsub in the same place at least twice of a first timing A and a second timing B.

Abstract: According to one embodiment of the present disclosure, a biometric sensor includes a flexible substrate, a first light-emitting part disposed on one side of the flexible substrate to output first light toward the body, a second light-emitting part disposed on one side of the flexible substrate to output second light different from the first light toward the body, an elastomer disposed on one side of the flexible substrate in a shape surrounding the first light-emitting part and the second light-emitting part, and a light-receiving part disposed on the other side of the flexible substrate to receive third light corresponding to the first light and fourth light corresponding to the second light.

Abstract: An electronic apparatus includes an output interface and a controller. The output interface is configured to output a signal on the basis of scattered light from a measured part. The controller is configured to calculate a temporal change of a power spectrum on the basis of the signal and detect noise included in the signal on the basis of the temporal change of the power spectrum.

Abstract: Various examples are described for detecting heart rate and respiratory rate by using measurements of light applied to skin through an article. For example, a sensor application obtains a set of measurements of light. The application compensates for a contribution of the article based on one or more known optical properties of the article. The sensor application further determines, from the set of measurements of light, a periodic change in amplitude. The sensor application identifies the periodic change in amplitude as a heart rate having an identical periodicity. The sensor application identifies a respiratory rate as equal to the rate of change of the heart rate.

Abstract: The present disclosure relates to a method and system for processing a photoplethysmogram (PPG) signal to improve accuracy of measurement of physiological parameters of a subject. The method may include removing a baseline drift from the PPG signal; obtaining a drift removed signal; filtering the drift removed signal; obtaining a filtered signal; performing motion artifact correction on the filtered signal; and obtaining a corrected signal.

Abstract: Medical devices and methods related to endoscopic systems suitable for hysterectomy and other purposes.

Abstract: The invention provides a body-worn system that continuously measures pulse oximetry and blood pressure, along with motion, posture, and activity level, from an ambulatory patient. The system features an oximetry probe that comfortably clips to the base of the patient's thumb, thereby freeing up their fingers for conventional activities in a hospital, such as reading and eating. The probe secures to the thumb and measures time-dependent signals corresponding to LEDs operating near 660 and 905 nm. Analog versions of these signals pass through a low-profile cable to a wrist-worn transceiver that encloses a processing unit. Also within the wrist-worn transceiver is an accelerometer, a wireless system that sends information through a network to a remote receiver, e.g. a computer located in a central nursing station.

Abstract: Injectable biophotonic sensors, systems relating to biophotonic sensors, and methods of using the injectable biophotonic sensors and systems are described. Methods and devices for delivering injectable biophotonic sensors to a subject are described. In an embodiment, an injectable biophotonic sensor comprises a printed circuit board (PCB); a light source; a first sensing element; a second sensing element; a receiver device or a induction coil; and an outer casing, wherein the first sensing element, the second sensing element, and the receiver device or the receiver induction coil are coupled to the PCB.

Abstract: The present disclosure includes a medical monitoring hub as the center of monitoring for a monitored patient. The hub is configured to receive and process a plurality of physiological parameters associated with the patient. The hub includes advanced analytical presentation views configured to provide timely, clinically-relevant, actionable information to care providers. In certain embodiments, the monitoring hub stores and is able to replay previously presented data reflective of the patient's condition.

Abstract: A system and method for controlling microbial growth on and in medical devices and implants, especially biofilm infections, involves using pulsed electric fields (PEF). To eradicate at least a portion of a biofilm on a medical implant, for example, 1500 volts can be applied through an electrode system, with pulse duration of 50 ?s and pulse delivery frequency of 2 Hz. In the clinical setting, systemic microbial therapy can be combined with PEF to achieve a synergistic effect leading to improved eradication of infections.

Abstract: A wearable device for detecting and/or measuring physiological information from a subject includes a housing, at least one optical emitter supported by the housing, at least one optical detector supported by the housing, a first light guide supported by the housing, a second light guide supported by the housing, a motion sensor supported by the housing, and a processor supported by the housing. The processor is configured to calculate footsteps, distinguish footsteps from heart beats, and to remove footstep motion artifacts from signals produced by the at least one optical detector. Also, the processor is configured to process signals produced by the at least one optical detector to determine subject heart rate and to produce integrity data about the subject heart rate. The process is further configured to generate a multiplexed output serial data string comprising the subject heart rate and the integrity data.

Abstract: A load sensing assembly for a spinal implant includes a set screw having a central opening that extends from a first end of the set screw toward a second end of the set screw. The second end of the set screw is configured to engage with an anchoring member. The load sensing assembly includes an antenna, an integrated circuit in communication with the antenna, where the integrated circuit is positioned within the central opening of the set screw, and a strain gauge in connection with the integrated circuit. The strain gauge is located within the central opening of the set screw in proximity to the second end of the set screw.

Abstract: A sleeve or sheath includes a body having a top opening. The body covers a handheld oximeter probe or a portion of the probe. The sleeve has a shape that approximately matches the oximeter probe or portion of the probe, which is covered by the sleeve. The sleeve has a top opening that allows a user to slide the oximeter probe into the sleeve. The sleeve is transparent to radiation emitted and collected by the oximeter probe. The sleeve is formed of a material that prevents patient tissue, fluid, viruses, bacteria, and fungus from contacting the covered portions of the oximeter probe. The sleeve leaves the probe relatively sterile after use so that little or no clearing of the probe is required for a subsequent use, such as when the probe is covered with a new, unused sleeve.

Abstract: Embodiments disclosed herein relate to devices and methods for monitoring one or more physiological parameters of a subject. In an embodiment, a wearable device comprises a substrate configured to attached to a subject's skin. The substrate comprises a middle portion arranged between two end portions, wherein the middle portion is more flexible than at least one of the end portions. The wearable device also comprises a physiological sensor arranged on the middle portion. The physiological sensor is configured to sense a physiological signal of the subject when the wearable device is attached to the subject's skin. And, the wearable device comprises one or more electrical components arranged on at least one of the end portions, wherein at least one of the one or more electrical components is coupled to the physiological sensor.

Abstract: A method of generating a model for generating a synthetic electrocardiography (ECG) signal comprises: receiving subject-specific training data for machine learning, said training data comprising a photoplethysmography (PPG) signal acquired from the subject and an ECG signal acquired from the subject, wherein the ECG signal provides a ground truth of the subject for associating the ECG signal with the PPG signal; using associated pairs of a time-series of the PPG signal and a corresponding time-series of the ECG signal as input to a deep neural network, DNN; and determining, through the DNN, a subject-specific model relating the PPG signal of the subject to the ECG signal of the subject for converting the PPG signal to a synthetic ECG signal using the subject-specific model.

Abstract: A method and system for monitoring oxygen saturation of a patient are provided. An example system includes a wearable device having a first optical sensor to measure a first red wavelength photoplethysmography (PPG) signal and a first infrared wavelength PPG signal and a second optical sensor to measure a second red wavelength PPG signal and a second infrared wavelength PPG signal. The system further includes a processor configured to determine that conditions for calibration of the first optical sensor are satisfied, determine a first ratio for obtaining the oxygen saturation, a first parameter for modifying the first red wavelength PPG signal, a second parameter for modifying the first infrared wavelength PPG signal, and a second ratio for obtaining the oxygen saturation. The processor is further configured to determine a value of the oxygen saturation and provide a message regarding a health status of the patient.

Abstract: A medical diagnostic device includes a wirelessly transmitted time data receiver and processor. Associated devices, methods and functionality are also described.

Abstract: An adaptive audio therapy system which detects and processes one or more individuals' conditions to provide adaptive, continuous audio therapy in real-time. The adaptive audio therapy system generally includes a detection device that is typically in physical contact with an individual, such as a pacifier or steering wheel. The detection device may include sensors to detect various conditions of the individual, such as heart rate, respiration rate, temperature, and the like. A computing device receives and processes the various conditions detected by the sensors. Based on the detected conditions, the computing device provides audio therapy which is adaptive to the condition of the patient and which is continuously adapted in real-time.

Abstract: A medical imaging device, comprising a illumination unit, can be configured to illuminate a tissue area with light from a first spectral range, comprising a range of visible wavelengths, and with light from a second spectral range, which is different from the first spectral range, an imaging unit, configured to detect light from the first spectral range and to generate a first image of the tissue area on the basis of the detected light from the first spectral range and furthermore configured to detect light from the second spectral range and to generate a second image of the tissue area on the basis of the detected light from the second spectral range, and a superposition unit, configured to generate a superimposed image on the basis of the first and second image in such a way that, in the superimposed image, on the basis of a visual highlighting, it is possible to identify whether and where the tissue area comprises highlight regions which are characterized by an increased emission of light from the second s

Abstract: The present invention relates to the field of medical monitoring, and in particular non-contact monitoring of one or more physiological parameters in a region of a patient during surgery. Systems, methods, and computer readable media are described for generating a pulsation field and/or a pulsation strength field of a region of interest (ROI) in a patient across a field of view of an image capture device, such as a video camera. The pulsation field and/or the pulsation strength field can be generated from changes in light intensities and/or colors of pixels in a video sequence captured by the image capture device. The pulsation field and/or the pulsation strength field can be combined with indocyanine green (ICG) information regarding ICG dye injected into the patient to identify sites where blood flow has decreased and/or ceased and that are at risk of hypoxia.

Abstract: In some embodiments, a self-monitoring intravenous catheter system is provided. An alarm controller is provided that receives signals representing a pH value, an oxygen saturation value, and a pressure value in proximity to the distal end of the catheter. By performing a fuzzy logic analysis of the values, the alarm controller is able to detect that the catheter is about to fail or has failed, and can cause alerts to be presented. In some embodiments, an intravenous catheter is provided that has a pH sensor and an oximeter disposed at a distal end of the catheter to obtain the pH value and oxygen saturation values analyzed by the alarm controller. Embodiments of the catheter and self-monitoring intravenous catheter system may be particularly useful in treating neonates, who are sensitive to catheter failure and are not capable of detecting the signs of failure themselves.

Abstract: Implementations described herein disclose an artificial intelligence (AI) based method for generating an oxygen saturation level output signal using the trained neural network. In one implementation, the method includes receiving a photoplethysmographic (PPG) signal, the PPG signal including a red PPG signal and an infrared PPG signal, generating an input feature matrix by performing time-frequency transform of the PPG signal, training a neural network using the input feature matrix and an oxygen saturation level input signal, and generating an oxygen saturation level output signal using the trained neural network.

Abstract: A sensing device for acquiring data from a finger. The device includes a carrier board having a stacked portion with a finger side and a canopy side. A tip wing extends from the stacked portion and wraps around the finger. Electrical components are coupled to the carrier board, including a first circuit board on the canopy side of the stacked portion, and one or more optical components electrically on the tip wing. The optical components are configured to transmit light towards the finger and to detect the light from the finger. The carrier board electrically couples the electrical components to acquire the data from the finger. A power system is positioned between the canopy side and the finger side of the carrier board, where the power system provides power to the electrical components via the carrier board. A cover secures the carrier board to the finger.

Abstract: A fluorescent image analyzer stores a reference fluorescent-sample image and a subject fluorescent-sample image. The reference fluorescent-sample image is an image obtained by illuminating a reference fluorescent sample about which relation of in-plane fluorescence intensities is known with linearly polarized light and capturing a first specific polarization component of fluorescence from the reference fluorescent sample. The subject fluorescent-sample image is an image obtained by illuminating a subject fluorescent sample with linearly polarized light and capturing a second specific polarization component of fluorescence from the subject fluorescent sample. The fluorescent image analyzer is configured to determine correction coefficients to correct non-uniformity in measurement of light intensities among pixels of a captured image based on the reference fluorescent-sample image, and correct light intensities of the pixels of the subject fluorescent-sample image based on the correction coefficients.

Abstract: A multi-purpose biometric sensor includes both a transmissive topology and reflective topology for measuring biometric information. The multi-purpose biometric sensor is configured to allow for dynamically switching between the transmissive topology and the reflective topology based on user input or a current measuring scenario. The multi-purpose biometric sensor includes multiple types of light emitting sources and is further configured to dynamically switch between different types of light emitting sources based on user input or a current measuring scenario. The multi-purpose biometric sensor is further configured to measure multiple biometric signals from a single sensor.

Abstract: An apparatus for estimating blood glucose using a photoplethysmography (PPG) signal is provided. The apparatus for estimating blood glucose includes: a pulse wave sensor configured to obtain a pulse wave signal from an object; and a processor configured to obtain at least two points from a waveform of the pulse wave signal, to extract a feature based on time values of the obtained at least two points, and to estimate blood glucose based on the extracted feature.

Abstract: A method of annotating medical data may involve receiving, by a first device, medical data from one or more sensors of one or more medical devices and non-medical event data from one or more non-medical devices. The non-medical event data may indicate a non-medical device type. The method may involve annotating the medical data according to the non-medical event data, to produce annotated medical data, and transmitting the annotated medical data to a second device.

Abstract: In some examples, a system includes an oxygen saturation sensing device configured to sense an oxygen saturation level of a patient and processing circuitry. The processing circuitry may be configured to receive a signal indicative of the oxygen saturation level of the patient, determine that the signal indicates the oxygen saturation level is at or below a desaturation threshold, and in response to determining the oxygen saturation level of the patient is at or below the desaturation threshold, predict, using an oxygen saturation prediction model, whether the oxygen saturation level of the patient will increase above the desaturation threshold by the end of a predefined time period. In response to predicting that the oxygen saturation level of the patient will increase above the desaturation threshold by the end of the predefined time period, the processing circuitry refrains from outputting an indication of the patient experiencing an oxygen desaturation event.

Abstract: An electronic device may include a display, a photoplethysmogram (PPG) sensor, a wireless communication circuit, a processor operatively connected to the display, the PPG sensor, and the wireless communication circuit, and a memory operatively connected to the processor. The electronic device implements the method, including monitoring blood glucose values of a user using the PPG sensor, displaying a notification prompting the user to measure blood glucose values using an external electronic device based at least partially on the monitored blood glucose values, and receive additional blood glucose values measured by the external electronic device using the wireless communication circuit.

Abstract: An electronic device according to an aspect of the present disclosure includes a touch screen. The electronic device includes a communication interface that may receive, from a touch pen, a pulse wave signal of a user which is measured from a finger of the user by the touch pen while the touch pen is placed on the touch screen. The electronic device includes a processor that may determine whether a measurement posture of the user is appropriate based on whether the finger touches the touch screen, and in response to determining that the user's measurement posture is appropriate, estimate bio-information of the user based on the received pulse wave signal.

Abstract: Provided is a biological information measuring instrument which can be easily and reliably worn on an appropriate position of an arm by a user. The biological information measuring instrument includes: a belt portion that is worn on a user's arm in a circumferential direction of the arm and disposed with a sensor for detecting a displacement of an arm muscle; and a case portion that is attached to a predetermined portion of the belt portion and houses a circuit component that processes a signal of the displacement detected by the sensor. The case portion has a shape of protruding from the belt portion in a longitudinal direction of the arm when the belt portion is worn on the arm, and amounts D1 and D2 of protrusions protruding in the longitudinal direction are different between one protrusion and the other protrusion.

Abstract: A method for assessing and reversing exercise impairment in adults having peripheral vascular disease includes quantifying a musculoskeletal deoxygenation level (MDL) of a human subject provided by a wearable near infrared spectroscopy system configured to measure the deoxygenation level during exercise, comparing the quantified MDL to a range of pre-determined healthy MDL values for the subject, and, if the quantified MDL is outside of the pre-determined target MDL values, determining a corrective exercise intensity level or ‘dose’ effective to bring the MDL of the subject within the target MDL values and reverse the exercise impairment.

Abstract: A non-invasive optical measurement system comprises a two-dimensional array of photonic integrated circuits (PICs) mechanically coupled to each other. Each PIC is configured for emitting sample light into an anatomical structure, such that the sample light is scattered by the anatomical structure, resulting in physiological-encoded signal light that exits the anatomical structure. Each PIC is further configured for detecting the signal light. The non-invasive optical measurement system further comprises processing circuitry configured for analyzing the detected signal light from each of the PICs, and based on this analysis, determining an occurrence and a three-dimensional spatial location of the physiological event in the anatomical structure.

Abstract: An electronic device includes: a support body including first and second planar portions facing each other, a first connecting portion connecting the first and second planar portions, and a first receptacle surrounded by the first and second planar portions and the first connecting portion; a projection being part of the second planar portion projecting outward from the first receptacle outside the first planar portion in plan view; a wiring substrate including a facing surface facing the support body and an opposite surface opposite to the facing surface, the wiring substrate being folded and attached along an inner surface of the first receptacle and a surface of the projection continuous with the inner surface of the first receptacle; a sensor element mounted on the facing surface attached to the inner surface of the first receptacle; and an antenna mounted on the opposite surface attached to the surface of the projection.