Abstract: A stand-on physiological sensor (e.g. floormat) measures vital signs and various hemodynamic parameters, including blood pressure and ECG waveforms. The sensor is similar in configuration to a common bathroom scale and includes electrodes that take electrical measurements from a patient's feet to generate bioimpedance waveforms, which are analyzed digitally to extract various other parameters, as well as a cuff-type blood pressure system that takes physical blood pressure measurements at one of the patient's feet. Blood pressure can also be calculated/derived from the bioimpedance waveforms. Measured parameters are transmitted wirelessly to facilitate remote monitoring of the patient for heart failure, chronic heart failure, end-stage renal disease, cardiac arrhythmias, and other degenerative diseases.

Abstract: A method includes affixing a co-planar sensor on a surface, using a processor, and providing an output. The method includes affixing a co-planar sensor on a surface at a first tissue site. The sensor has a force transducer disposed at an aperture of a rigid guard member. The guard member and the transducer are in co-planar alignment. The transducer is configured to provide an electrical signal corresponding to an internal pressure at the first tissue site. The method includes using the processor to compare the internal pressure with a reference value. Based on the comparison, the method includes providing an output corresponding to compartment syndrome at the first tissue site.

Abstract: A stand-on physiological sensor (e.g. floormat) measures vital signs and various hemodynamic parameters, including blood pressure and ECG waveforms. The sensor is similar in configuration to a common bathroom scale and includes electrodes that take electrical measurements from a patient's feet to generate bioimpedance waveforms, which are analyzed digitally to extract various other parameters, as well as a cuff-type blood pressure system that takes physical blood pressure measurements at one of the patient's feet. Blood pressure can also be calculated/derived from the bioimpedance waveforms. Measured parameters are transmitted wirelessly to facilitate remote monitoring of the patient for heart failure, chronic heart failure, end-stage renal disease, cardiac arrhythmias, and other degenerative diseases.

Abstract: A blood pressure gauge for monitoring the blood pressure values of a patient in a darkened or low light environment. The blood pressure gauge is selectively illuminated when an internal air pressure within an attached blood pressure cuff is first detected or after it has reached a predetermined threshold value as determined by a pressure transducer in the blood pressure gauge. The blood pressure gauge is illuminated by a plurality of light emitting diodes or by plurality of components comprised of photoluminescent material. The blood pressure cuff is inflated by the actuation of a bulb attached to the blood pressure gauge. The bulb is actuated or squeezed against a stationary hand grip portion of the blood pressure gauge so as to provide a greater compressive force and deliver a larger volume of air to the blood pressure cuff.

Abstract: A physiological monitoring system features a Floormat and Handheld Sensor connected by a cable. A user stands on the Floormat and grips the Handheld Sensor. These components measure time-dependent physiological waveforms from a user over a conduction pathway extending from the user's hand or wrist to their feet. The Handheld Sensor and Floormat use a combination of electrodes that inject current into the user's body and collect bioelectric signals that, with processing, yield ECG, impedance, and bioreactance waveforms. Simultaneously, the Handheld Sensor measures photoplethysmogram waveforms with red and infrared radiation and pressure waveforms from the user's fingers and wrist, while the Floormat measures signals from load cells to determine ‘force’ waveforms to determine the user's weight, and ballistocardiogram waveforms to determine parameters related to cardiac contractility.

Abstract: A handheld device measures all vital signs and some hemodynamic parameters from the human body and transmits measured information wirelessly to a web-based system, where the information can be analyzed by a clinician to help diagnose a patient. The system utilizes our discovery that bio-impedance signals used to determine vital signs and hemodynamic parameters can be measured over a conduction pathway extending from the patient's wrist to a location on their thoracic cavity, e.g. their chest or navel. The device's form factor can include re-usable electrode materials to reduce costs. Measurements made by the handheld device, which use the belly button as a ‘fiducial’ marker, facilitate consistent, daily measurements, thereby reducing positioning errors that reduce accuracy of standard impedance measurements. In this and other ways, the handheld device provides an effective tool for characterizing patients with chronic diseases, such as heart failure, renal disease, and hypertension.

Abstract: Provided are systems and methods for noninvasively assessing intracranial pressure by controllably osculating at least a portion of a subject's ocular globe while applying a force sufficient to collapse an intraocular blood vessel and correlating the collapse pressure to intracranial pressure. Also provided are ophthalmic components useful in ophthalmic imaging applications, such as retinal, corneal, and pupil imaging. The components may include an optical contact surface that has a radius of curvature that is greater than the radius of curvature of a subject's cornea.

Abstract: A mobile cardiac monitoring device is disclosed. The mobile cardiac monitoring device receives voltage-time measurements of a subset of electrocardiogram (ECG) leads for a user, and derives a full set of ECG leads from the voltage-time measurements of the subset of ECG leads. The mobile cardiac monitoring device calculates a heart rate and monitors the cardiac rhythm of the user based on at least one of the subset of ECG leads and calculates a cardiac electrical biomarker (CEB) based on the derived ECG. The mobile cardiac device detects a trigger condition based on the calculated CEB and transmits an alert in response to detecting the trigger condition.

Abstract: A system (100) for monitoring and diagnosing heart conditions includes a sensor array (102) with accelerometers, an electrocardiogram sensor, and a system to synchronously capture and process (103, 105, or 106) composite heart signals. The system performs separation, identification and marking (201-205 or 501-509) of the signals, to extract information in cardiac vibrations. Machine learning, auditory scene analysis, or spare coding approaches can be used to resolve source separation problems. Analysis of the composite signals separates different vibration signals (302, 303, 304, 305), identifies streams for particular valve signal, and marks them with event time information with respect to a synchronous electrocardiogram signal (306). The psychoacoustic analysis mimics human auditory processing to enhance hearing of heart valve sounds by separating valve vibrations from the composite signal, and providing extraction, identification, marking and display of individual valve signals.

Abstract: An electrode assembly for measuring bio-signals is disclosed. The electrode assembly comprises a body, a fastening member extending from the body and provided on one side of the body, the fastening member including a spring groove formed therein and an aperture penetrating therethrough, and a spring inserted into the spring groove. The aperture receives a fastening stud of a patch which is supplied from outside. The spring compresses the fastening stud received in the aperture such that the fastening member fixes the fastening stud thereto.

Abstract: This disclosure relates to a spherical handheld biosensor array device for physiological status monitoring. More particularly, this disclosure relates to biomedical devices that periodically monitor physiological vital and non-vital parameters among multiple users using a biosensor array.

Abstract: A system and method for calculating a quantitative EEG is disclosed herein. The present invention achieves a level of artifact reduction that the QEEG is now practical on a continuous monitoring basis since artifact reduction is continuously applied to an EEG recording.

Abstract: A system for marking cardiac time intervals from heart valve signals includes a non-invasive sensor unit for capturing electrical signals and composite vibration objects, a memory containing computer instructions, and one or more processors coupled to the memory. The one or more processors causes the one or more processors to perform operations including separating a plurality of individual heart vibration events into heart valve signals from the composite vibration objects, and marking cardiac time interval from the heart valve signals by detecting individual heartbeats and processing cumulative energy within the individual heartbeat to set a threshold to set a marking point.

Abstract: A stochastic Bayesian nonlinear filtering system and method that improves the filtering of noisy signals by providing efficiency, power, speed, and flexibility. The filter only requires the likelihood function p(observation|state) to determine the system state and works in various measurement models. This allows for the processing of noisy signals to be used in real time, such as in a biofeedback device that senses noisy surface electomyography muscle electrical activity, filters the sensed signal using the nonlinear filtering method, and provides vibrations based on the muscular activity.

Abstract: A system for identifying heart valve signals includes a non-invasive sensor unit for capturing electrical signals and composite vibration objects, a memory containing computer instructions, and one or more processors coupled to the memory, where the one or more processors are configured to perform the steps of separating a plurality of individual heart vibration events from the composite vibration objects by using at least one among bin-wise clustering and permutation alignment, or non-negative matrix factorization, or deep belief networks and tagging the plurality of individual heart vibration events using at least one among principal component analysis, Gabor filtering, generalized cross correlation, phase transform, smoothed coherent transformation, Roth correlation or band filtering.

Abstract: A system for monitoring and diagnosing heart conditions includes a sensor array with accelerometers, an electrocardiogram sensor, and a system to capture and process the composite heart signals. The system performs source separation to extract information contained in cardio pulmonic vibrations. The system can use machine learning, auditory scene analysis, spare coding, determined Models, Principal Component Analysis (PCA), Independent Component Analysis ICA, Singular Value Decomposition (SVD), Bin-wise Clustering and Permutation posterior probability alignment, Undetermined Models, Sparseness condition, Dictionary learning, Convolutive models, K-SVD Matching Pursuit, Non-negative matrix factorization and Deep Belief Networks (Restricted Boltzmann Machine) approaches to the source separation problem. Other embodiments are disclosed.

Abstract: Apparatus for monitoring a brain signal, especially indicative of muscle fatigue, comprises at least three sensors sensing neuronal activity, wherein one sensor (11) comprises a reference electrode and the other sensors (15, 16) comprise sensing electrodes, wherein the reference sensor (11) serves as a common reference for the other sensors (15, 16). The reference sensor (11) is placed within the quadrangle defined by the four positions [F5-F1-C 1-C5] or on a corridor of 10 millimetres width along the line between Fpz to Oz, the first sensing sensor is placed within the quadrangle [C1-C2-P2-P1], and the second sensing sensor is placed within the quadrangle [FT7-FC3-CP3-TP7], with the proviso that the reference electrode is not positioned on the same position as is one of the two sensing sensors and wherein the positions of the sensors delimiting the quadrangles are defined according to the 10-10 Electrode Placement System of the American Clinical Neurophysiology Society.

Abstract: An electrocardiography patch is provided. A flexible backing is formed of an elongated strip of stretchable material and a pair of electrodes is respectively affixed on a contact surface of each end of the elongated strip. A flexible circuit is affixed on each end of the elongated strip and includes a pair of circuit traces electrically coupled to each electrode. A non-conductive receptacle is securely adhered on the one end of the elongated strip opposite the contact surface and formed to removably receive an electrocardiography monitor and house a battery. Electrical pads are provided on a bottom surface of the non-conductive receptacle to interface with electrical contacts protruding from the electrocardiography monitor. A pair of the electrical pads is formed to electrically couple with the electrodes. A pair of battery leads is formed on the non-conductive receptacle to electrically interface the battery to another pair of the electrical pads.

Abstract: The present disclosure relates to a wearable monitor device and methods and systems for using such a device. In certain embodiments, the wearable monitor records cardiac data from a mammal and extracts particular features of interest. These features are then transmitted and used to provide health-related information about the mammal.

Abstract: A handheld device measures all vital signs and some hemodynamic parameters from the human body and transmits measured information wirelessly to a web-based system, where the information can be analyzed by a clinician to help diagnose a patient. The system utilizes our discovery that bio-impedance signals used to determine vital signs and hemodynamic parameters can be measured over a conduction pathway extending from the patient's wrist to a location on their thoracic cavity, e.g. their chest or navel. The device's form factor can include re-usable electrode materials to reduce costs. Measurements made by the handheld device, which use the belly button as a ‘fiducial’ marker, facilitate consistent, daily measurements, thereby reducing positioning errors that reduce accuracy of standard impedance measurements. In this and other ways, the handheld device provides an effective tool for characterizing patients with chronic diseases, such as heart failure, renal disease, and hypertension.

Abstract: The invention describes a new Imaging modality based on Linear Velocity Imaging Tomography; its applications include differentiating between malignant and benign tissues, the ability to correlate an ECG trace with actual disorders of the heart and Imaging Brain communications.

Abstract: A handheld device measures all vital signs and some hemodynamic parameters from the human body and transmits measured information wirelessly to a web-based system, where the information can be analyzed by a clinician to help diagnose a patient. The system utilizes our discovery that bio-impedance signals used to determine vital signs and hemodynamic parameters can be measured over a conduction pathway extending from the patient's wrist to a location on their thoracic cavity, e.g. their chest or navel. The device's form factor can include re-usable electrode materials to reduce costs. Measurements made by the handheld device, which use the belly button as a ‘fiducial’ marker, facilitate consistent, daily measurements, thereby reducing positioning errors that reduce accuracy of standard impedance measurements. In this and other ways, the handheld device provides an effective tool for characterizing patients with chronic diseases, such as heart failure, renal disease, and hypertension.

Abstract: Example methods, apparatus/systems and articles of manufacture for determining intensity of a biological response to a presentation are disclosed. An example method includes accessing galvanic skin response (GSR) data obtained from a subject while exposed to a presentation. The GSR data includes a plurality of trough-to-peak instances. The example method includes generating a GSR intensity profile by assigning trough-to-peak scores to corresponding ones of the trough-to-peak instances, defining a plurality of time windows, and assigning window scores to corresponding ones of the time windows based on the trough-to-peaks scores of the trough-to-peak instances occurring within the corresponding time windows. The example method also includes determining an effectiveness of the presentation based on the window scores of the GSR intensity profile.

Abstract: A stand-on physiological sensor (e.g. floormat) measures vital signs and various hemodynamic parameters, including blood pressure and ECG waveforms. The sensor is similar in configuration to a common bathroom scale and includes electrodes that take electrical measurements from a patient's feet to generate bioimpedance waveforms, which are analyzed digitally to extract various other parameters, as well as a cuff-type blood pressure system that takes physical blood pressure measurements at one of the patient's feet. Blood pressure can also be calculated/derived from the bioimpedance waveforms. Measured parameters are transmitted wirelessly to facilitate remote monitoring of the patient for heart failure, chronic heart failure, end-stage renal disease, cardiac arrhythmias, and other degenerative diseases.

Abstract: An apparatus for detecting abnormal masses such as breast cancer includes a measurement sensor configured to obtain a voltage at a first area of a first breast of a subject; a reference sensor configured to obtain a voltage at a second area of a second breast of the subject, a position of the first area corresponding to a position of the second area; and a detector, wherein the detector includes a differential amplifier configured to amplify a voltage input from the at least one of the measurement sensor and the reference sensor; an active low pass filter configured to pass a signal frequency of a low frequency band among signals transmitted from the differential amplifier; a driver amplifier configured to amplify a signal passed through the active low pass filter; and an analog-to-digital (AD) converter configured to convert the signal amplified by the driver amplifier into a digital signal.

Abstract: A magnetic resonance system, useful for imaging a patient, comprising: (a) a magnetic resonance device (MRD) for imaging a patient, comprising an open bore, the MRD at least partially contained in an envelope comprising in its circumference at least one recess; and, (b) an MRI-safe cart made of MRI-safe material, comprising a substantially horizontal base and at least one substantially horizontal incubator above the base, the base and the incubator are interconnected by at least one pillar. At least a portion of the cart and the MRD are configured to fit together such that at least a portion of the incubator is reversibly housed within the MRD, and further at least a portion of the base is reversibly housed within at least one recess.

Abstract: A method comprises: storing, in a memory of a computing device, (i) a preoperative image of patient tissue obtained using a first imaging modality and registered to a first frame of reference, and (ii) anatomical data defining a plurality of neural tracts in the patient tissue; receiving, at a processor connected with the memory, a location in the first frame of reference for application of a cortical stimulator pad to the patient tissue; receiving, at the processor, a range of influence of the cortical stimulator pad; based on the location and the range of influence, selecting, at the processor, an intersected neural tract from the plurality of neural tracts, a portion of the intersected neural tract being located within the range of influence; and controlling, at the processor, the display to render the preoperative image, the location and the intersected neural tract according to the first frame of reference.

Abstract: A transducer includes a planar coil coupled to a magnetic flux guide. The magnetic flux guide includes an array of nanowires. The transducer could include a plurality of magnetic flux guides and a plurality of planar coils stacked together. The flux guides and planar coils could alternative in the stacked configuration.

Abstract: A system that includes at least one coil that is radio-translucent and includes at least one conductor that includes lithium.

Abstract: A position detection system includes: a capsule medical device having therein a magnetic field generator for generating a magnetic field; magnetic field detectors for detecting the magnetic field and outputting detection signals; and a processor including hardware. The processor is configured to: calculate a position of the capsule medical device using at least one of the detection signals; determine whether or not proper position detection of the capsule medical device based on the detection signals is possible using a threshold that is a value based on at least one of output values of the detection signals output by the magnetic field detectors under a predetermined condition; decide a determination value using at least one of the output values of the detection signals; and determine that the proper position detection of the capsule medical device is not possible when the determination value is smaller than the threshold.

Abstract: A portable system is provided for measuring a ketone, such as an acetone, in the breath or other bodily fluid of a user. The system includes a portable measurement device that analyzes fluid samples and generates corresponding ketone measurements. The portable measurement device communicates with an application which runs on a smartphone or other mobile device of the user. The application tracks, and generates graphs of, the ketone measurements, and may include various features for facilitating the analysis of the measurements.

Abstract: A stand-on physiological sensor (e.g. floormat) measures vital signs and various hemodynamic parameters, including blood pressure and ECG waveforms. The sensor is similar in configuration to a common bathroom scale and includes electrodes that take electrical measurements from a patient's feet to generate bioimpedance waveforms, which are analyzed digitally to extract various other parameters, as well as a cuff-type blood pressure system that takes physical blood pressure measurements at one of the patient's feet. Blood pressure can also be calculated/derived from the bioimpedance waveforms. Measured parameters are transmitted wirelessly to facilitate remote monitoring of the patient for heart failure, chronic heart failure, end-stage renal disease, cardiac arrhythmias, and other degenerative diseases.

Abstract: A method, system and software for monitoring a signal from a living subject to measure a function of the living subject. Specifically, a computer method, computer system and software for accurately calibrating respiratory inductance plethysmography and esophageal manometry signals to measure effort of breathing before and after extubation of a patient to provide an automated real-time interpretation for a clinician of whether or not the patient has upper airway obstruction, and severity of the same. The method, system and software can be adapted specifically for a child or infant.

Abstract: A device and method is described for the collection of breath or air samples into a chemically clean bag or balloon, to facilitate analysis of volatile organic compounds (VOCs) in low concentrations in the collected samples. A reservoir of activated charcoal is introduced into the bag or balloon for initial removal of VOCs and it is then replaced with a similar reservoir of activated charcoal until the bag or balloon is employed to collect a sample. The device fulfills a long-felt need for collection of breath and air samples with a high VOC signal-to-noise ratio.

Abstract: A system and method for measuring and analyzing locomotion is provided. The system may include a gait analysis apparatus that is configured to provide multi-dimensional measurements of the gait of an individual as the individual traverses the apparatus. The multiple dimensions may include force, space, time, and frequency. The gait analysis apparatus may be configured to provide a gait measurement processing device with the multi-dimensional measurements. Based on the multi-dimensional measurements, the gait measurement processing device may, for example, diagnose the test subject with a particular NM disease and/or injury, monitor progression of the particular NM disease and/or injury over time, and determine which measurements may be used as biomarkers to identify the particular NM disease and/or injury.

Abstract: A device for measuring an expanded internal orifice of a patient includes an orifice- expanding device, a pressure measuring device, and a size-measuring device. The size- measuring device measures a dimension of the orifice after it has been expanded by the orifice-expanding device.

Abstract: The invention described herein is a system that features a Floormat and Handheld Sensor that operate in concert with a user's mobile device. The Floormat resembles a conventional bathroom scale, but features an enhanced set of measurements that include pulse rate and/or heart rate, SpO2, respiratory rate, weight, body composition, and Fluids. The Handheld Sensor features an integrated form factor that fits in a user's hand, which measures parameters such as blood pressure (e.g. systolic, diastolic, mean and pulse pressures), stroke volume, and cardiac output. Measurements of stroke volume and cardiac output require information from the Floormat (e.g., weight and body composition) to be sent to and processed by the Handheld Sensor. The Handheld Sensor can also make redundant measurements of heart rate, SpO2, and respiratory rate. Both systems transmit information through a wireless interface to a web-based system, where a clinician can analyze it to help diagnose a user.

Abstract: A method and a device for retrieving a breathing signal is disclosed. Firstly, a triaxial acceleration signal is retrieved for a fixed period. Then, multivariate empirical mode decomposition (MEMD) is performed on the triaxial acceleration signal, so as to sequentially obtain a plurality of intrinsic mode functions (IMFs). Finally, an average inclination angle of the triaxial acceleration signal corresponding to each intrinsic mode function is sequentially calculated, and the intrinsic mode function corresponding to the average inclination angle within a predetermined angle range is added to a set. All the intrinsic mode functions are added up to obtain and output a breathing signal when an amount of the intrinsic mode functions in the set equals to a predetermined value being a natural number.

Abstract: A method for distinguishing between individual human subjects using plethysmographic waveforms. In one embodiment, the method comprises the steps of: receiving a plurality of plethysmographic signals from different individuals; normalizing the signals to the same period length and mean; changing the basis of each of the plurality of signals to obtain its basis vectors and coefficients; reducing the number of coefficients for each signal in the plurality of signals; and calculating the covariance matrix and mean for each individual's set of normalized and dimensionally-reduced plethysmograph waveforms. In another embodiment, the method further comprises the step of taking the Mahalanobis distance between each new plethysmograph waveform that has also been normalized and dimensionally reduced and the stored models of all individuals. In yet another embodiment, the method further comprises the step of finding the index of the stored model with the minimum Mahalanobis distance.

Abstract: Biometric monitoring devices, including various technologies that may be implemented in such devices, are discussed herein. Additionally, techniques for enhancing GPS speed and distance measurements based on step counts measured by a biometric monitoring device are provided. Such techniques may, in some implementations, involve blending two independently-measured data streams of raw distance traveled—one based on inter-coordinate GPS coordinate distances and one based on step count and stride length—using a Kalman filter to provide an enhanced-accuracy measurement of distance or speed traveled. In some other or additional implementations, distances or speeds calculated based on inter-coordinate GPS coordinate distances may be smoothed with a smoothing constant that is proportional to the variance in measured step count.

Abstract: A system and method for utilizing an activity monitoring device that includes, during a set of initial activity sessions, collecting the kinematic data from an activity monitoring device and generating a temporal record of at least one biomechanical signal that is calculated from the kinematic data; analyzing temporal changes in the biomechanical signals during the initial activity sessions and characterizing a fatigue model; and, during a subsequent activity session collecting current kinematic data of a participant and generating at least one current biomechanical signal from the current kinematic data, monitoring the fatigue state through processing the at least one current biomechanical signal according to the fatigue model, and triggering feedback in a user interface based on the fatigue state.

Abstract: Device, system and methods for using body worn sensors to analyze human body motion. The device, often configured to be worn on the user's wrist, arm, neck, belt or other location, comprises a processor, an output device (often a wireless transceiver), and at least one accelerometer, angle, location, direction, or physiological state sensor. The processor may be configured for various functions, such as analyzing habitual user activities, establishing normal baselines, classifying types of motion and reporting, and logging sensor readings or analysis results. Various algorithms may be used to determine when significant deviations from baseline values occur, and, depending on the type of deviation, the output device can transmit data and alerts. In some embodiments, the data and alerts may be further analyzed by other computerized devices such as mobile phones (smartphones), computers, internet servers, and the like.

Abstract: A control system for controlling an accommodation demand detection in an ophthalmic technical system includes at least one sensor configured to detect a signal sequence from a body itself or an environmental signal sequence and to convert the detected signal sequence into measurement signals, and at least one detector configured to convert the measurement signals into a control signal that influences the accommodation demand detection. The detector includes a signal processor configured to compare the measurement signals with a reference signal bandwidth and to generate the control signal When the measurement signals are covered by a predetermined reference signal bandwidth.

Abstract: Device and method for classifying the activity and/or counting steps of a user. A method for classifying the activity of a user can comprise measuring accelerometer data for a plurality of axes; identifying a most active one of the plurality of axes based on the accelerometer data; and classifying the activity of the user based on a signal amplitude of the accelerometer data for the most active axis and one or more threshold values.

Abstract: The efficacy of tissue piercing elements in the area of transdermal drug delivery is well-documented. Multiple studies have shown that enhancement of skin permeation via creation of microscopic pores in the stratum corneum can greatly improve the delivery rates of drugs. However, skin perforation with tissue piercing elements is not the only factor affecting the rate of drug transport. Other factors including such as the formulation of the drug and rate of closure of the micropores closure also need to be considered. Similarly micro tissue piercing elements have been used with less success by several workers for continuous glucose monitoring.

Abstract: The present invention relates to a device which uses optical fibers to form a tube hat for a finger tip to collect all Raman photons.

Abstract: A system for detection of blood trace analytes is disclosed. The system comprises an illumination disc supporting a plurality of sources of electromagnetic radiation and rotatable relative to an interdigital location of a subject, and a spectrometer disc supporting a plurality of spectrometers able to process the electromagnetic radiation from the illumination disc and rotatable relative to the interdigital location of a subject at a position opposite that of the illumination disc.

Abstract: A solution containing a target molecule and a reference molecule is illuminated to obtain Raman signals. An optical metasurface is used as a diffractive optical element to split the Raman signal from the target molecule and the Raman signal from the reference molecule. The target and reference Raman signals can be detected at different locations with different photodetectors, and the target molecule concentration in the solution is determined by comparing the target and reference Raman signals.

Abstract: Disclosed are devices for determining an analyte concentration (e.g., glucose). The devices comprise a sensor configured to generate a signal associated with a concentration of an analyte and a sensing membrane located over the sensor. The sensing membrane comprises an enzyme layer, wherein the enzyme layer comprises an enzyme and a polymer comprising polyurethane and/or polyurea segments and one or more zwitterionic repeating units. The enzyme layer protects the enzyme and prevents it from leaching from the sensing membrane into a host or deactivating.

Abstract: On-body units are provided and include a transcutaneous analyte sensor, electronic circuitry electrically coupled to the sensor, and an on-body housing having electrical contacts disposed thereon. The on-body housing comprises a substantially flat surface and a curved and convex surface opposite the substantially flat surface. Systems and methods including the on-body units are also provided. Methods for performing continuity measurements using on-body units are also provided. The methods include positioning an on-body unit (OBU) on a skin of a subject, contacting a continuity test instrument to the OBU; and performing a continuity measurement with the continuity test instrument. An AC signal may be provided across two electrical contacts, or a DC signal may be provided across two electrical contacts in opposite directions for the same amount of time. The measurement may be performed with one electrical contact, or with isolated electrical contacts.